Creation of Cybook 2416 (actually Gen4) repository

arch/um/os-Linux/Makefile

@@ -0,0 +1,28 @@
+# 
+# Copyright (C) 2000 Jeff Dike (jdike@karaya.com)
+# Licensed under the GPL
+#
+
+obj-y = aio.o elf_aux.o execvp.o file.o helper.o irq.o main.o mem.o process.o \
+	sigio.o signal.o start_up.o time.o trap.o tty.o uaccess.o umid.o tls.o \
+	user_syms.o util.o drivers/ sys-$(SUBARCH)/
+
+obj-$(CONFIG_MODE_SKAS) += skas/
+
+obj-$(CONFIG_MODE_TT) += tt.o
+user-objs-$(CONFIG_MODE_TT) += tt.o
+
+obj-$(CONFIG_TTY_LOG) += tty_log.o
+user-objs-$(CONFIG_TTY_LOG) += tty_log.o
+
+USER_OBJS := $(user-objs-y) aio.o elf_aux.o execvp.o file.o helper.o irq.o \
+	main.o mem.o process.o sigio.o signal.o start_up.o time.o trap.o tty.o \
+	tls.o uaccess.o umid.o util.o
+
+CFLAGS_user_syms.o += -DSUBARCH_$(SUBARCH)
+
+HAVE_AIO_ABI := $(shell [ -r /usr/include/linux/aio_abi.h ] && \
+	echo -DHAVE_AIO_ABI )
+CFLAGS_aio.o += $(HAVE_AIO_ABI)
+
+include arch/um/scripts/Makefile.rules

arch/um/os-Linux/aio.c

@@ -0,0 +1,403 @@
+/*
+ * Copyright (C) 2004 Jeff Dike (jdike@addtoit.com)
+ * Licensed under the GPL
+ */
+
+#include <stdlib.h>
+#include <unistd.h>
+#include <signal.h>
+#include <errno.h>
+#include <sched.h>
+#include <sys/syscall.h>
+#include "os.h"
+#include "aio.h"
+#include "init.h"
+#include "user.h"
+#include "mode.h"
+
+struct aio_thread_req {
+	enum aio_type type;
+	int io_fd;
+	unsigned long long offset;
+	char *buf;
+	int len;
+	struct aio_context *aio;
+};
+
+#if defined(HAVE_AIO_ABI)
+#include <linux/aio_abi.h>
+
+/* If we have the headers, we are going to build with AIO enabled.
+ * If we don't have aio in libc, we define the necessary stubs here.
+ */
+
+#if !defined(HAVE_AIO_LIBC)
+
+static long io_setup(int n, aio_context_t *ctxp)
+{
+	return syscall(__NR_io_setup, n, ctxp);
+}
+
+static long io_submit(aio_context_t ctx, long nr, struct iocb **iocbpp)
+{
+	return syscall(__NR_io_submit, ctx, nr, iocbpp);
+}
+
+static long io_getevents(aio_context_t ctx_id, long min_nr, long nr,
+			 struct io_event *events, struct timespec *timeout)
+{
+	return syscall(__NR_io_getevents, ctx_id, min_nr, nr, events, timeout);
+}
+
+#endif
+
+/* The AIO_MMAP cases force the mmapped page into memory here
+ * rather than in whatever place first touches the data.  I used
+ * to do this by touching the page, but that's delicate because
+ * gcc is prone to optimizing that away.  So, what's done here
+ * is we read from the descriptor from which the page was
+ * mapped.  The caller is required to pass an offset which is
+ * inside the page that was mapped.  Thus, when the read
+ * returns, we know that the page is in the page cache, and
+ * that it now backs the mmapped area.
+ */
+
+static int do_aio(aio_context_t ctx, enum aio_type type, int fd, char *buf,
+		  int len, unsigned long long offset, struct aio_context *aio)
+{
+	struct iocb iocb, *iocbp = &iocb;
+	char c;
+	int err;
+
+	iocb = ((struct iocb) { .aio_data 	= (unsigned long) aio,
+				.aio_reqprio	= 0,
+				.aio_fildes	= fd,
+				.aio_buf	= (unsigned long) buf,
+				.aio_nbytes	= len,
+				.aio_offset	= offset,
+				.aio_reserved1	= 0,
+				.aio_reserved2	= 0,
+				.aio_reserved3	= 0 });
+
+	switch(type){
+	case AIO_READ:
+		iocb.aio_lio_opcode = IOCB_CMD_PREAD;
+		err = io_submit(ctx, 1, &iocbp);
+		break;
+	case AIO_WRITE:
+		iocb.aio_lio_opcode = IOCB_CMD_PWRITE;
+		err = io_submit(ctx, 1, &iocbp);
+		break;
+	case AIO_MMAP:
+		iocb.aio_lio_opcode = IOCB_CMD_PREAD;
+		iocb.aio_buf = (unsigned long) &c;
+		iocb.aio_nbytes = sizeof(c);
+		err = io_submit(ctx, 1, &iocbp);
+		break;
+	default:
+		printk("Bogus op in do_aio - %d\n", type);
+		err = -EINVAL;
+		break;
+	}
+
+	if(err > 0)
+		err = 0;
+	else
+		err = -errno;
+
+	return err;
+}
+
+/* Initialized in an initcall and unchanged thereafter */
+static aio_context_t ctx = 0;
+
+static int aio_thread(void *arg)
+{
+	struct aio_thread_reply reply;
+	struct io_event event;
+	int err, n, reply_fd;
+
+	signal(SIGWINCH, SIG_IGN);
+
+	while(1){
+		n = io_getevents(ctx, 1, 1, &event, NULL);
+		if(n < 0){
+			if(errno == EINTR)
+				continue;
+			printk("aio_thread - io_getevents failed, "
+			       "errno = %d\n", errno);
+		}
+		else {
+			reply = ((struct aio_thread_reply)
+				{ .data = (void *) (long) event.data,
+						.err	= event.res });
+			reply_fd = ((struct aio_context *) reply.data)->reply_fd;
+			err = os_write_file(reply_fd, &reply, sizeof(reply));
+			if(err != sizeof(reply))
+				printk("aio_thread - write failed, fd = %d, "
+				       "err = %d\n", reply_fd, -err);
+		}
+	}
+	return 0;
+}
+
+#endif
+
+static int do_not_aio(struct aio_thread_req *req)
+{
+	char c;
+	int err;
+
+	switch(req->type){
+	case AIO_READ:
+		err = os_seek_file(req->io_fd, req->offset);
+		if(err)
+			goto out;
+
+		err = os_read_file(req->io_fd, req->buf, req->len);
+		break;
+	case AIO_WRITE:
+		err = os_seek_file(req->io_fd, req->offset);
+		if(err)
+			goto out;
+
+		err = os_write_file(req->io_fd, req->buf, req->len);
+		break;
+	case AIO_MMAP:
+		err = os_seek_file(req->io_fd, req->offset);
+		if(err)
+			goto out;
+
+		err = os_read_file(req->io_fd, &c, sizeof(c));
+		break;
+	default:
+		printk("do_not_aio - bad request type : %d\n", req->type);
+		err = -EINVAL;
+		break;
+	}
+
+out:
+	return err;
+}
+
+/* These are initialized in initcalls and not changed */
+static int aio_req_fd_r = -1;
+static int aio_req_fd_w = -1;
+static int aio_pid = -1;
+
+static int not_aio_thread(void *arg)
+{
+	struct aio_thread_req req;
+	struct aio_thread_reply reply;
+	int err;
+
+	signal(SIGWINCH, SIG_IGN);
+	while(1){
+		err = os_read_file(aio_req_fd_r, &req, sizeof(req));
+		if(err != sizeof(req)){
+			if(err < 0)
+				printk("not_aio_thread - read failed, "
+				       "fd = %d, err = %d\n", aio_req_fd_r,
+				       -err);
+			else {
+				printk("not_aio_thread - short read, fd = %d, "
+				       "length = %d\n", aio_req_fd_r, err);
+			}
+			continue;
+		}
+		err = do_not_aio(&req);
+		reply = ((struct aio_thread_reply) { .data 	= req.aio,
+					 .err	= err });
+		err = os_write_file(req.aio->reply_fd, &reply, sizeof(reply));
+		if(err != sizeof(reply))
+			printk("not_aio_thread - write failed, fd = %d, "
+			       "err = %d\n", req.aio->reply_fd, -err);
+	}
+
+	return 0;
+}
+
+static int init_aio_24(void)
+{
+	unsigned long stack;
+	int fds[2], err;
+
+	err = os_pipe(fds, 1, 1);
+	if(err)
+		goto out;
+
+	aio_req_fd_w = fds[0];
+	aio_req_fd_r = fds[1];
+	err = run_helper_thread(not_aio_thread, NULL,
+				CLONE_FILES | CLONE_VM | SIGCHLD, &stack, 0);
+	if(err < 0)
+		goto out_close_pipe;
+
+	aio_pid = err;
+	goto out;
+
+out_close_pipe:
+	os_close_file(fds[0]);
+	os_close_file(fds[1]);
+	aio_req_fd_w = -1;
+	aio_req_fd_r = -1;
+out:
+#ifndef HAVE_AIO_ABI
+	printk("/usr/include/linux/aio_abi.h not present during build\n");
+#endif
+	printk("2.6 host AIO support not used - falling back to I/O "
+	       "thread\n");
+	return 0;
+}
+
+#ifdef HAVE_AIO_ABI
+#define DEFAULT_24_AIO 0
+static int init_aio_26(void)
+{
+	unsigned long stack;
+	int err;
+
+	if(io_setup(256, &ctx)){
+		err = -errno;
+		printk("aio_thread failed to initialize context, err = %d\n",
+		       errno);
+		return err;
+	}
+
+	err = run_helper_thread(aio_thread, NULL,
+				CLONE_FILES | CLONE_VM | SIGCHLD, &stack, 0);
+	if(err < 0)
+		return err;
+
+	aio_pid = err;
+
+	printk("Using 2.6 host AIO\n");
+	return 0;
+}
+
+static int submit_aio_26(enum aio_type type, int io_fd, char *buf, int len,
+			 unsigned long long offset, struct aio_context *aio)
+{
+	struct aio_thread_reply reply;
+	int err;
+
+	err = do_aio(ctx, type, io_fd, buf, len, offset, aio);
+	if(err){
+		reply = ((struct aio_thread_reply) { .data = aio,
+					 .err  = err });
+		err = os_write_file(aio->reply_fd, &reply, sizeof(reply));
+		if(err != sizeof(reply))
+			printk("submit_aio_26 - write failed, "
+			       "fd = %d, err = %d\n", aio->reply_fd, -err);
+		else err = 0;
+	}
+
+	return err;
+}
+
+#else
+#define DEFAULT_24_AIO 1
+static int init_aio_26(void)
+{
+	return -ENOSYS;
+}
+
+static int submit_aio_26(enum aio_type type, int io_fd, char *buf, int len,
+			 unsigned long long offset, struct aio_context *aio)
+{
+	return -ENOSYS;
+}
+#endif
+
+/* Initialized in an initcall and unchanged thereafter */
+static int aio_24 = DEFAULT_24_AIO;
+
+static int __init set_aio_24(char *name, int *add)
+{
+	aio_24 = 1;
+	return 0;
+}
+
+__uml_setup("aio=2.4", set_aio_24,
+"aio=2.4\n"
+"    This is used to force UML to use 2.4-style AIO even when 2.6 AIO is\n"
+"    available.  2.4 AIO is a single thread that handles one request at a\n"
+"    time, synchronously.  2.6 AIO is a thread which uses the 2.6 AIO \n"
+"    interface to handle an arbitrary number of pending requests.  2.6 AIO \n"
+"    is not available in tt mode, on 2.4 hosts, or when UML is built with\n"
+"    /usr/include/linux/aio_abi.h not available.  Many distributions don't\n"
+"    include aio_abi.h, so you will need to copy it from a kernel tree to\n"
+"    your /usr/include/linux in order to build an AIO-capable UML\n\n"
+);
+
+static int init_aio(void)
+{
+	int err;
+
+	CHOOSE_MODE(({ if(!aio_24){
+			    printk("Disabling 2.6 AIO in tt mode\n");
+			    aio_24 = 1;
+		    } }), (void) 0);
+
+	if(!aio_24){
+		err = init_aio_26();
+		if(err && (errno == ENOSYS)){
+			printk("2.6 AIO not supported on the host - "
+			       "reverting to 2.4 AIO\n");
+			aio_24 = 1;
+		}
+		else return err;
+	}
+
+	if(aio_24)
+		return init_aio_24();
+
+	return 0;
+}
+
+/* The reason for the __initcall/__uml_exitcall asymmetry is that init_aio
+ * needs to be called when the kernel is running because it calls run_helper,
+ * which needs get_free_page.  exit_aio is a __uml_exitcall because the generic
+ * kernel does not run __exitcalls on shutdown, and can't because many of them
+ * break when called outside of module unloading.
+ */
+__initcall(init_aio);
+
+static void exit_aio(void)
+{
+	if(aio_pid != -1)
+		os_kill_process(aio_pid, 1);
+}
+
+__uml_exitcall(exit_aio);
+
+static int submit_aio_24(enum aio_type type, int io_fd, char *buf, int len,
+			 unsigned long long offset, struct aio_context *aio)
+{
+	struct aio_thread_req req = { .type 		= type,
+				      .io_fd		= io_fd,
+				      .offset		= offset,
+				      .buf		= buf,
+				      .len		= len,
+				      .aio		= aio,
+	};
+	int err;
+
+	err = os_write_file(aio_req_fd_w, &req, sizeof(req));
+	if(err == sizeof(req))
+		err = 0;
+
+	return err;
+}
+
+int submit_aio(enum aio_type type, int io_fd, char *buf, int len,
+	       unsigned long long offset, int reply_fd,
+	       struct aio_context *aio)
+{
+	aio->reply_fd = reply_fd;
+	if(aio_24)
+		return submit_aio_24(type, io_fd, buf, len, offset, aio);
+	else {
+		return submit_aio_26(type, io_fd, buf, len, offset, aio);
+	}
+}

arch/um/os-Linux/drivers/Makefile

@@ -0,0 +1,13 @@
+# 
+# Copyright (C) 2000, 2002 Jeff Dike (jdike@karaya.com)
+# Licensed under the GPL
+#
+
+ethertap-objs := ethertap_kern.o ethertap_user.o
+tuntap-objs := tuntap_kern.o tuntap_user.o
+
+obj-y = 
+obj-$(CONFIG_UML_NET_ETHERTAP) += ethertap.o
+obj-$(CONFIG_UML_NET_TUNTAP) += tuntap.o
+
+include arch/um/scripts/Makefile.rules

arch/um/os-Linux/drivers/etap.h

@@ -0,0 +1,27 @@
+/* 
+ * Copyright (C) 2001 Jeff Dike (jdike@karaya.com)
+ * Licensed under the GPL
+ */
+
+#include "net_user.h"
+
+struct ethertap_data {
+	char *dev_name;
+	char *gate_addr;
+	int data_fd;
+	int control_fd;
+	void *dev;
+};
+
+extern const struct net_user_info ethertap_user_info;
+
+/*
+ * Overrides for Emacs so that we follow Linus's tabbing style.
+ * Emacs will notice this stuff at the end of the file and automatically
+ * adjust the settings for this buffer only.  This must remain at the end
+ * of the file.
+ * ---------------------------------------------------------------------------
+ * Local variables:
+ * c-file-style: "linux"
+ * End:
+ */

arch/um/os-Linux/drivers/ethertap_kern.c

@@ -0,0 +1,108 @@
+/*
+ * Copyright (C) 2001 Lennert Buytenhek (buytenh@gnu.org) and 
+ * James Leu (jleu@mindspring.net).
+ * Copyright (C) 2001 by various other people who didn't put their name here.
+ * Licensed under the GPL.
+ */
+
+#include "linux/init.h"
+#include "linux/netdevice.h"
+#include "linux/etherdevice.h"
+#include "net_kern.h"
+#include "net_user.h"
+#include "etap.h"
+
+struct ethertap_init {
+	char *dev_name;
+	char *gate_addr;
+};
+
+static void etap_init(struct net_device *dev, void *data)
+{
+	struct uml_net_private *pri;
+	struct ethertap_data *epri;
+	struct ethertap_init *init = data;
+
+	pri = dev->priv;
+	epri = (struct ethertap_data *) pri->user;
+	epri->dev_name = init->dev_name;
+	epri->gate_addr = init->gate_addr;
+	epri->data_fd = -1;
+	epri->control_fd = -1;
+	epri->dev = dev;
+
+	printk("ethertap backend - %s", epri->dev_name);
+	if (epri->gate_addr != NULL)
+		printk(", IP = %s", epri->gate_addr);
+	printk("\n");
+}
+
+static int etap_read(int fd, struct sk_buff **skb, struct uml_net_private *lp)
+{
+	int len;
+
+	*skb = ether_adjust_skb(*skb, ETH_HEADER_ETHERTAP);
+	if(*skb == NULL) return(-ENOMEM);
+	len = net_recvfrom(fd, (*skb)->mac.raw, 
+			   (*skb)->dev->mtu + 2 * ETH_HEADER_ETHERTAP);
+	if(len <= 0) return(len);
+	skb_pull(*skb, 2);
+	len -= 2;
+	return(len);
+}
+
+static int etap_write(int fd, struct sk_buff **skb, struct uml_net_private *lp)
+{
+	if(skb_headroom(*skb) < 2){
+	  	struct sk_buff *skb2;
+
+		skb2 = skb_realloc_headroom(*skb, 2);
+		dev_kfree_skb(*skb);
+		if (skb2 == NULL) return(-ENOMEM);
+		*skb = skb2;
+	}
+	skb_push(*skb, 2);
+	return(net_send(fd, (*skb)->data, (*skb)->len));
+}
+
+const struct net_kern_info ethertap_kern_info = {
+	.init			= etap_init,
+	.protocol		= eth_protocol,
+	.read			= etap_read,
+	.write 			= etap_write,
+};
+
+int ethertap_setup(char *str, char **mac_out, void *data)
+{
+	struct ethertap_init *init = data;
+
+	*init = ((struct ethertap_init)
+		{ .dev_name 	= NULL,
+		  .gate_addr 	= NULL });
+	if(tap_setup_common(str, "ethertap", &init->dev_name, mac_out,
+			    &init->gate_addr))
+		return(0);
+	if(init->dev_name == NULL){
+		printk("ethertap_setup : Missing tap device name\n");
+		return(0);
+	}
+
+	return(1);
+}
+
+static struct transport ethertap_transport = {
+	.list 		= LIST_HEAD_INIT(ethertap_transport.list),
+	.name 		= "ethertap",
+	.setup  	= ethertap_setup,
+	.user 		= &ethertap_user_info,
+	.kern 		= &ethertap_kern_info,
+	.private_size 	= sizeof(struct ethertap_data),
+};
+
+static int register_ethertap(void)
+{
+	register_transport(&ethertap_transport);
+	return 0;
+}
+
+late_initcall(register_ethertap);

arch/um/os-Linux/drivers/ethertap_user.c

@@ -0,0 +1,240 @@
+/*
+ * Copyright (C) 2001 Lennert Buytenhek (buytenh@gnu.org) and 
+ * James Leu (jleu@mindspring.net).
+ * Copyright (C) 2001 by various other people who didn't put their name here.
+ * Licensed under the GPL.
+ */
+
+#include <stdio.h>
+#include <unistd.h>
+#include <stddef.h>
+#include <stdlib.h>
+#include <sys/errno.h>
+#include <sys/socket.h>
+#include <sys/wait.h>
+#include <sys/un.h>
+#include <net/if.h>
+#include "user.h"
+#include "kern_util.h"
+#include "user_util.h"
+#include "net_user.h"
+#include "etap.h"
+#include "os.h"
+#include "um_malloc.h"
+
+#define MAX_PACKET ETH_MAX_PACKET
+
+void etap_user_init(void *data, void *dev)
+{
+	struct ethertap_data *pri = data;
+
+	pri->dev = dev;
+}
+
+struct addr_change {
+	enum { ADD_ADDR, DEL_ADDR } what;
+	unsigned char addr[4];
+	unsigned char netmask[4];
+};
+
+static void etap_change(int op, unsigned char *addr, unsigned char *netmask,
+			int fd)
+{
+	struct addr_change change;
+	char *output;
+	int n;
+
+	change.what = op;
+	memcpy(change.addr, addr, sizeof(change.addr));
+	memcpy(change.netmask, netmask, sizeof(change.netmask));
+	n = os_write_file(fd, &change, sizeof(change));
+	if(n != sizeof(change))
+		printk("etap_change - request failed, err = %d\n", -n);
+	output = um_kmalloc(page_size());
+	if(output == NULL)
+		printk("etap_change : Failed to allocate output buffer\n");
+	read_output(fd, output, page_size());
+	if(output != NULL){
+		printk("%s", output);
+		kfree(output);
+	}
+}
+
+static void etap_open_addr(unsigned char *addr, unsigned char *netmask,
+			   void *arg)
+{
+	etap_change(ADD_ADDR, addr, netmask, *((int *) arg));
+}
+
+static void etap_close_addr(unsigned char *addr, unsigned char *netmask,
+			    void *arg)
+{
+	etap_change(DEL_ADDR, addr, netmask, *((int *) arg));
+}
+
+struct etap_pre_exec_data {
+	int control_remote;
+	int control_me;
+	int data_me;
+};
+
+static void etap_pre_exec(void *arg)
+{
+	struct etap_pre_exec_data *data = arg;
+
+	dup2(data->control_remote, 1);
+	os_close_file(data->data_me);
+	os_close_file(data->control_me);
+}
+
+static int etap_tramp(char *dev, char *gate, int control_me, 
+		      int control_remote, int data_me, int data_remote)
+{
+	struct etap_pre_exec_data pe_data;
+	int pid, status, err, n;
+	char version_buf[sizeof("nnnnn\0")];
+	char data_fd_buf[sizeof("nnnnnn\0")];
+	char gate_buf[sizeof("nnn.nnn.nnn.nnn\0")];
+	char *setup_args[] = { "uml_net", version_buf, "ethertap", dev,
+			       data_fd_buf, gate_buf, NULL };
+	char *nosetup_args[] = { "uml_net", version_buf, "ethertap", 
+				 dev, data_fd_buf, NULL };
+	char **args, c;
+
+	sprintf(data_fd_buf, "%d", data_remote);
+	sprintf(version_buf, "%d", UML_NET_VERSION);
+	if(gate != NULL){
+		strcpy(gate_buf, gate);
+		args = setup_args;
+	}
+	else args = nosetup_args;
+
+	err = 0;
+	pe_data.control_remote = control_remote;
+	pe_data.control_me = control_me;
+	pe_data.data_me = data_me;
+	pid = run_helper(etap_pre_exec, &pe_data, args, NULL);
+
+	if(pid < 0) err = pid;
+	os_close_file(data_remote);
+	os_close_file(control_remote);
+	n = os_read_file(control_me, &c, sizeof(c));
+	if(n != sizeof(c)){
+		printk("etap_tramp : read of status failed, err = %d\n", -n);
+		return(-EINVAL);
+	}
+	if(c != 1){
+		printk("etap_tramp : uml_net failed\n");
+		err = -EINVAL;
+		CATCH_EINTR(n = waitpid(pid, &status, 0));
+		if(n < 0)
+			err = -errno;
+		else if(!WIFEXITED(status) || (WEXITSTATUS(status) != 1))
+			printk("uml_net didn't exit with status 1\n");
+	}
+	return(err);
+}
+
+static int etap_open(void *data)
+{
+	struct ethertap_data *pri = data;
+	char *output;
+	int data_fds[2], control_fds[2], err, output_len;
+
+	err = tap_open_common(pri->dev, pri->gate_addr);
+	if(err) return(err);
+
+	err = os_pipe(data_fds, 0, 0);
+	if(err < 0){
+		printk("data os_pipe failed - err = %d\n", -err);
+		return(err);
+	}
+
+	err = os_pipe(control_fds, 1, 0);
+	if(err < 0){
+		printk("control os_pipe failed - err = %d\n", -err);
+		return(err);
+	}
+	
+	err = etap_tramp(pri->dev_name, pri->gate_addr, control_fds[0], 
+			 control_fds[1], data_fds[0], data_fds[1]);
+	output_len = page_size();
+	output = um_kmalloc(output_len);
+	read_output(control_fds[0], output, output_len);
+
+	if(output == NULL)
+		printk("etap_open : failed to allocate output buffer\n");
+	else {
+		printk("%s", output);
+		kfree(output);
+	}
+
+	if(err < 0){
+		printk("etap_tramp failed - err = %d\n", -err);
+		return(err);
+	}
+
+	pri->data_fd = data_fds[0];
+	pri->control_fd = control_fds[0];
+	iter_addresses(pri->dev, etap_open_addr, &pri->control_fd);
+	return(data_fds[0]);
+}
+
+static void etap_close(int fd, void *data)
+{
+	struct ethertap_data *pri = data;
+
+	iter_addresses(pri->dev, etap_close_addr, &pri->control_fd);
+	os_close_file(fd);
+	os_shutdown_socket(pri->data_fd, 1, 1);
+	os_close_file(pri->data_fd);
+	pri->data_fd = -1;
+	os_close_file(pri->control_fd);
+	pri->control_fd = -1;
+}
+
+static int etap_set_mtu(int mtu, void *data)
+{
+	return(mtu);
+}
+
+static void etap_add_addr(unsigned char *addr, unsigned char *netmask,
+			  void *data)
+{
+	struct ethertap_data *pri = data;
+
+	tap_check_ips(pri->gate_addr, addr);
+	if(pri->control_fd == -1) return;
+	etap_open_addr(addr, netmask, &pri->control_fd);
+}
+
+static void etap_del_addr(unsigned char *addr, unsigned char *netmask, 
+			  void *data)
+{
+	struct ethertap_data *pri = data;
+
+	if(pri->control_fd == -1) return;
+	etap_close_addr(addr, netmask, &pri->control_fd);
+}
+
+const struct net_user_info ethertap_user_info = {
+	.init		= etap_user_init,
+	.open		= etap_open,
+	.close	 	= etap_close,
+	.remove	 	= NULL,
+	.set_mtu	= etap_set_mtu,
+	.add_address	= etap_add_addr,
+	.delete_address = etap_del_addr,
+	.max_packet	= MAX_PACKET - ETH_HEADER_ETHERTAP
+};
+
+/*
+ * Overrides for Emacs so that we follow Linus's tabbing style.
+ * Emacs will notice this stuff at the end of the file and automatically
+ * adjust the settings for this buffer only.  This must remain at the end
+ * of the file.
+ * ---------------------------------------------------------------------------
+ * Local variables:
+ * c-file-style: "linux"
+ * End:
+ */

arch/um/os-Linux/drivers/tuntap.h

@@ -0,0 +1,32 @@
+/* 
+ * Copyright (C) 2001, 2002 Jeff Dike (jdike@karaya.com)
+ * Licensed under the GPL
+ */
+
+#ifndef __UM_TUNTAP_H
+#define __UM_TUNTAP_H
+
+#include "net_user.h"
+
+struct tuntap_data {
+	char *dev_name;
+	int fixed_config;
+	char *gate_addr;
+	int fd;
+	void *dev;
+};
+
+extern const struct net_user_info tuntap_user_info;
+
+#endif
+
+/*
+ * Overrides for Emacs so that we follow Linus's tabbing style.
+ * Emacs will notice this stuff at the end of the file and automatically
+ * adjust the settings for this buffer only.  This must remain at the end
+ * of the file.
+ * ---------------------------------------------------------------------------
+ * Local variables:
+ * c-file-style: "linux"
+ * End:
+ */

arch/um/os-Linux/drivers/tuntap_kern.c

@@ -0,0 +1,93 @@
+/* 
+ * Copyright (C) 2001 Jeff Dike (jdike@karaya.com)
+ * Licensed under the GPL
+ */
+
+#include "linux/stddef.h"
+#include "linux/netdevice.h"
+#include "linux/etherdevice.h"
+#include "linux/skbuff.h"
+#include "linux/init.h"
+#include "asm/errno.h"
+#include "net_kern.h"
+#include "net_user.h"
+#include "tuntap.h"
+
+struct tuntap_init {
+	char *dev_name;
+	char *gate_addr;
+};
+
+static void tuntap_init(struct net_device *dev, void *data)
+{
+	struct uml_net_private *pri;
+	struct tuntap_data *tpri;
+	struct tuntap_init *init = data;
+
+	pri = dev->priv;
+	tpri = (struct tuntap_data *) pri->user;
+	tpri->dev_name = init->dev_name;
+	tpri->fixed_config = (init->dev_name != NULL);
+	tpri->gate_addr = init->gate_addr;
+	tpri->fd = -1;
+	tpri->dev = dev;
+
+	printk("TUN/TAP backend - ");
+	if (tpri->gate_addr != NULL)
+		printk("IP = %s", tpri->gate_addr);
+	printk("\n");
+}
+
+static int tuntap_read(int fd, struct sk_buff **skb, 
+		       struct uml_net_private *lp)
+{
+	*skb = ether_adjust_skb(*skb, ETH_HEADER_OTHER);
+	if(*skb == NULL) return(-ENOMEM);
+	return(net_read(fd, (*skb)->mac.raw, 
+			(*skb)->dev->mtu + ETH_HEADER_OTHER));
+}
+
+static int tuntap_write(int fd, struct sk_buff **skb, 
+			struct uml_net_private *lp)
+{
+	return(net_write(fd, (*skb)->data, (*skb)->len));
+}
+
+const struct net_kern_info tuntap_kern_info = {
+	.init			= tuntap_init,
+	.protocol		= eth_protocol,
+	.read			= tuntap_read,
+	.write 			= tuntap_write,
+};
+
+int tuntap_setup(char *str, char **mac_out, void *data)
+{
+	struct tuntap_init *init = data;
+
+	*init = ((struct tuntap_init)
+		{ .dev_name 	= NULL,
+		  .gate_addr 	= NULL });
+	if(tap_setup_common(str, "tuntap", &init->dev_name, mac_out,
+			    &init->gate_addr))
+		return(0);
+
+	return(1);
+}
+
+static struct transport tuntap_transport = {
+	.list 		= LIST_HEAD_INIT(tuntap_transport.list),
+	.name 		= "tuntap",
+	.setup  	= tuntap_setup,
+	.user 		= &tuntap_user_info,
+	.kern 		= &tuntap_kern_info,
+	.private_size 	= sizeof(struct tuntap_data),
+	.setup_size 	= sizeof(struct tuntap_init),
+};
+
+static int register_tuntap(void)
+{
+	register_transport(&tuntap_transport);
+	return 0;
+}
+
+late_initcall(register_tuntap);

arch/um/os-Linux/drivers/tuntap_user.c

@@ -0,0 +1,228 @@
+/* 
+ * Copyright (C) 2001, 2002 Jeff Dike (jdike@karaya.com)
+ * Licensed under the GPL
+ */
+
+#include <stdio.h>
+#include <stddef.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <errno.h>
+#include <sys/wait.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+#include <sys/uio.h>
+#include <sys/ioctl.h>
+#include <net/if.h>
+#include <linux/if_tun.h>
+#include "net_user.h"
+#include "tuntap.h"
+#include "kern_util.h"
+#include "user_util.h"
+#include "user.h"
+#include "os.h"
+
+#define MAX_PACKET ETH_MAX_PACKET
+
+void tuntap_user_init(void *data, void *dev)
+{
+	struct tuntap_data *pri = data;
+
+	pri->dev = dev;
+}
+
+static void tuntap_add_addr(unsigned char *addr, unsigned char *netmask,
+			    void *data)
+{
+	struct tuntap_data *pri = data;
+
+	tap_check_ips(pri->gate_addr, addr);
+	if((pri->fd == -1) || pri->fixed_config) return;
+	open_addr(addr, netmask, pri->dev_name);
+}
+
+static void tuntap_del_addr(unsigned char *addr, unsigned char *netmask,
+			    void *data)
+{
+	struct tuntap_data *pri = data;
+
+	if((pri->fd == -1) || pri->fixed_config) return;
+	close_addr(addr, netmask, pri->dev_name);
+}
+
+struct tuntap_pre_exec_data {
+	int stdout;
+	int close_me;
+};
+
+static void tuntap_pre_exec(void *arg)
+{
+	struct tuntap_pre_exec_data *data = arg;
+	
+	dup2(data->stdout, 1);
+	os_close_file(data->close_me);
+}
+
+static int tuntap_open_tramp(char *gate, int *fd_out, int me, int remote,
+			     char *buffer, int buffer_len, int *used_out)
+{
+	struct tuntap_pre_exec_data data;
+	char version_buf[sizeof("nnnnn\0")];
+	char *argv[] = { "uml_net", version_buf, "tuntap", "up", gate,
+			 NULL };
+	char buf[CMSG_SPACE(sizeof(*fd_out))];
+	struct msghdr msg;
+	struct cmsghdr *cmsg;
+	struct iovec iov;
+	int pid, n, err;
+
+	sprintf(version_buf, "%d", UML_NET_VERSION);
+
+	data.stdout = remote;
+	data.close_me = me;
+
+	pid = run_helper(tuntap_pre_exec, &data, argv, NULL);
+
+	if(pid < 0) return(-pid);
+
+	os_close_file(remote);
+
+	msg.msg_name = NULL;
+	msg.msg_namelen = 0;
+	if(buffer != NULL){
+		iov = ((struct iovec) { buffer, buffer_len });
+		msg.msg_iov = &iov;
+		msg.msg_iovlen = 1;
+	}
+	else {
+		msg.msg_iov = NULL;
+		msg.msg_iovlen = 0;
+	}
+	msg.msg_control = buf;
+	msg.msg_controllen = sizeof(buf);
+	msg.msg_flags = 0;
+	n = recvmsg(me, &msg, 0);
+	*used_out = n;
+	if(n < 0){
+		err = -errno;
+		printk("tuntap_open_tramp : recvmsg failed - errno = %d\n", 
+		       errno);
+		return err;
+	}
+	CATCH_EINTR(waitpid(pid, NULL, 0));
+
+	cmsg = CMSG_FIRSTHDR(&msg);
+	if(cmsg == NULL){
+		printk("tuntap_open_tramp : didn't receive a message\n");
+		return(-EINVAL);
+	}
+	if((cmsg->cmsg_level != SOL_SOCKET) || 
+	   (cmsg->cmsg_type != SCM_RIGHTS)){
+		printk("tuntap_open_tramp : didn't receive a descriptor\n");
+		return(-EINVAL);
+	}
+	*fd_out = ((int *) CMSG_DATA(cmsg))[0];
+	os_set_exec_close(*fd_out, 1);
+	return(0);
+}
+
+static int tuntap_open(void *data)
+{
+	struct ifreq ifr;
+	struct tuntap_data *pri = data;
+	char *output, *buffer;
+	int err, fds[2], len, used;
+
+	err = tap_open_common(pri->dev, pri->gate_addr);
+	if(err < 0)
+		return(err);
+
+	if(pri->fixed_config){
+		pri->fd = os_open_file("/dev/net/tun",
+				       of_cloexec(of_rdwr(OPENFLAGS())), 0);
+		if(pri->fd < 0){
+			printk("Failed to open /dev/net/tun, err = %d\n",
+			       -pri->fd);
+			return(pri->fd);
+		}
+		memset(&ifr, 0, sizeof(ifr));
+		ifr.ifr_flags = IFF_TAP | IFF_NO_PI;
+		strlcpy(ifr.ifr_name, pri->dev_name, sizeof(ifr.ifr_name));
+		if(ioctl(pri->fd, TUNSETIFF, (void *) &ifr) < 0){
+			err = -errno;
+			printk("TUNSETIFF failed, errno = %d\n", errno);
+			os_close_file(pri->fd);
+			return err;
+		}
+	}
+	else {
+		err = os_pipe(fds, 0, 0);
+		if(err < 0){
+			printk("tuntap_open : os_pipe failed - err = %d\n",
+			       -err);
+			return(err);
+		}
+
+		buffer = get_output_buffer(&len);
+		if(buffer != NULL) len--;
+		used = 0;
+
+		err = tuntap_open_tramp(pri->gate_addr, &pri->fd, fds[0],
+					fds[1], buffer, len, &used);
+
+		output = buffer;
+		if(err < 0) {
+			printk("%s", output);
+			free_output_buffer(buffer);
+			printk("tuntap_open_tramp failed - err = %d\n", -err);
+			return(err);
+		}
+
+		pri->dev_name = uml_strdup(buffer);
+		output += IFNAMSIZ;
+		printk("%s", output);
+		free_output_buffer(buffer);
+
+		os_close_file(fds[0]);
+		iter_addresses(pri->dev, open_addr, pri->dev_name);
+	}
+
+	return(pri->fd);
+}
+
+static void tuntap_close(int fd, void *data)
+{
+	struct tuntap_data *pri = data;
+
+	if(!pri->fixed_config) 
+		iter_addresses(pri->dev, close_addr, pri->dev_name);
+	os_close_file(fd);
+	pri->fd = -1;
+}
+
+static int tuntap_set_mtu(int mtu, void *data)
+{
+	return(mtu);
+}
+
+const struct net_user_info tuntap_user_info = {
+	.init		= tuntap_user_init,
+	.open		= tuntap_open,
+	.close	 	= tuntap_close,
+	.remove	 	= NULL,
+	.set_mtu	= tuntap_set_mtu,
+	.add_address	= tuntap_add_addr,
+	.delete_address = tuntap_del_addr,
+	.max_packet	= MAX_PACKET
+};
+
+/*
+ * Overrides for Emacs so that we follow Linus's tabbing style.
+ * Emacs will notice this stuff at the end of the file and automatically
+ * adjust the settings for this buffer only.  This must remain at the end
+ * of the file.
+ * ---------------------------------------------------------------------------
+ * Local variables:
+ * c-file-style: "linux"
+ * End:
+ */

arch/um/os-Linux/elf_aux.c

@@ -0,0 +1,79 @@
+/*
+ *  arch/um/kernel/elf_aux.c
+ *
+ *  Scan the Elf auxiliary vector provided by the host to extract
+ *  information about vsyscall-page, etc.
+ *
+ *  Copyright (C) 2004 Fujitsu Siemens Computers GmbH
+ *  Author: Bodo Stroesser (bodo.stroesser@fujitsu-siemens.com)
+ */
+#include <elf.h>
+#include <stddef.h>
+#include "init.h"
+#include "elf_user.h"
+#include "mem_user.h"
+#include <kern_constants.h>
+
+/* Use the one from the kernel - the host may miss it, if having old headers. */
+#if UM_ELF_CLASS == UM_ELFCLASS32
+typedef Elf32_auxv_t elf_auxv_t;
+#else
+typedef Elf64_auxv_t elf_auxv_t;
+#endif
+
+/* These are initialized very early in boot and never changed */
+char * elf_aux_platform;
+long elf_aux_hwcap;
+unsigned long vsyscall_ehdr;
+unsigned long vsyscall_end;
+unsigned long __kernel_vsyscall;
+
+__init void scan_elf_aux( char **envp)
+{
+	long page_size = 0;
+	elf_auxv_t * auxv;
+
+	while ( *envp++ != NULL) ;
+
+	for ( auxv = (elf_auxv_t *)envp; auxv->a_type != AT_NULL; auxv++) {
+		switch ( auxv->a_type ) {
+			case AT_SYSINFO:
+				__kernel_vsyscall = auxv->a_un.a_val;
+				/* See if the page is under TASK_SIZE */
+				if (__kernel_vsyscall < (unsigned long) envp)
+					__kernel_vsyscall = 0;
+				break;
+			case AT_SYSINFO_EHDR:
+				vsyscall_ehdr = auxv->a_un.a_val;
+				/* See if the page is under TASK_SIZE */
+				if (vsyscall_ehdr < (unsigned long) envp)
+					vsyscall_ehdr = 0;
+				break;
+			case AT_HWCAP:
+				elf_aux_hwcap = auxv->a_un.a_val;
+				break;
+			case AT_PLATFORM:
+                                /* elf.h removed the pointer elements from
+                                 * a_un, so we have to use a_val, which is
+                                 * all that's left.
+                                 */
+				elf_aux_platform =
+					(char *) (long) auxv->a_un.a_val;
+				break;
+			case AT_PAGESZ:
+				page_size = auxv->a_un.a_val;
+				break;
+		}
+	}
+	if ( ! __kernel_vsyscall || ! vsyscall_ehdr ||
+	     ! elf_aux_hwcap || ! elf_aux_platform ||
+	     ! page_size || (vsyscall_ehdr % page_size) ) {
+		__kernel_vsyscall = 0;
+		vsyscall_ehdr = 0;
+		elf_aux_hwcap = 0;
+		elf_aux_platform = "i586";
+	}
+	else {
+		vsyscall_end = vsyscall_ehdr + page_size;
+	}
+}

arch/um/os-Linux/execvp.c

@@ -0,0 +1,149 @@
+/* Copyright (C) 2006 by Paolo Giarrusso - modified from glibc' execvp.c.
+   Original copyright notice follows:
+
+   Copyright (C) 1991,92,1995-99,2002,2004 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+#include <unistd.h>
+
+#include <stdbool.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+#include <limits.h>
+
+#ifndef TEST
+#include "um_malloc.h"
+#else
+#include <stdio.h>
+#define um_kmalloc malloc
+#endif
+#include "os.h"
+
+/* Execute FILE, searching in the `PATH' environment variable if it contains
+   no slashes, with arguments ARGV and environment from `environ'.  */
+int execvp_noalloc(char *buf, const char *file, char *const argv[])
+{
+	if (*file == '\0') {
+		return -ENOENT;
+	}
+
+	if (strchr (file, '/') != NULL) {
+		/* Don't search when it contains a slash.  */
+		execv(file, argv);
+	} else {
+		int got_eacces;
+		size_t len, pathlen;
+		char *name, *p;
+		char *path = getenv("PATH");
+		if (path == NULL)
+			path = ":/bin:/usr/bin";
+
+		len = strlen(file) + 1;
+		pathlen = strlen(path);
+		/* Copy the file name at the top.  */
+		name = memcpy(buf + pathlen + 1, file, len);
+		/* And add the slash.  */
+		*--name = '/';
+
+		got_eacces = 0;
+		p = path;
+		do {
+			char *startp;
+
+			path = p;
+			//Let's avoid this GNU extension.
+			//p = strchrnul (path, ':');
+			p = strchr(path, ':');
+			if (!p)
+				p = strchr(path, '\0');
+
+			if (p == path)
+				/* Two adjacent colons, or a colon at the beginning or the end
+				   of `PATH' means to search the current directory.  */
+				startp = name + 1;
+			else
+				startp = memcpy(name - (p - path), path, p - path);
+
+			/* Try to execute this name.  If it works, execv will not return.  */
+			execv(startp, argv);
+
+			/*
+			if (errno == ENOEXEC) {
+			}
+			*/
+
+			switch (errno) {
+				case EACCES:
+					/* Record the we got a `Permission denied' error.  If we end
+					   up finding no executable we can use, we want to diagnose
+					   that we did find one but were denied access.  */
+					got_eacces = 1;
+				case ENOENT:
+				case ESTALE:
+				case ENOTDIR:
+					/* Those errors indicate the file is missing or not executable
+					   by us, in which case we want to just try the next path
+					   directory.  */
+				case ENODEV:
+				case ETIMEDOUT:
+					/* Some strange filesystems like AFS return even
+					   stranger error numbers.  They cannot reasonably mean
+					   anything else so ignore those, too.  */
+				case ENOEXEC:
+					/* We won't go searching for the shell
+					 * if it is not executable - the Linux
+					 * kernel already handles this enough,
+					 * for us. */
+					break;
+
+				default:
+					/* Some other error means we found an executable file, but
+					   something went wrong executing it; return the error to our
+					   caller.  */
+					return -errno;
+			}
+		} while (*p++ != '\0');
+
+		/* We tried every element and none of them worked.  */
+		if (got_eacces)
+			/* At least one failure was due to permissions, so report that
+			   error.  */
+			return -EACCES;
+	}
+
+	/* Return the error from the last attempt (probably ENOENT).  */
+	return -errno;
+}
+#ifdef TEST
+int main(int argc, char**argv)
+{
+	char buf[PATH_MAX];
+	int ret;
+	argc--;
+	if (!argc) {
+		fprintf(stderr, "Not enough arguments\n");
+		return 1;
+	}
+	argv++;
+	if (ret = execvp_noalloc(buf, argv[0], argv)) {
+		errno = -ret;
+		perror("execvp_noalloc");
+	}
+	return 0;
+}
+#endif

arch/um/os-Linux/file.c

@@ -0,0 +1,643 @@
+/*
+ * Copyright (C) 2002 Jeff Dike (jdike@karaya.com)
+ * Licensed under the GPL
+ */
+
+#include <stdio.h>
+#include <unistd.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <signal.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+#include <sys/ioctl.h>
+#include <sys/mount.h>
+#include <sys/uio.h>
+#include "os.h"
+#include "user.h"
+#include "kern_util.h"
+#include "user_util.h"
+
+static void copy_stat(struct uml_stat *dst, struct stat64 *src)
+{
+	*dst = ((struct uml_stat) {
+		.ust_dev     = src->st_dev,     /* device */
+		.ust_ino     = src->st_ino,     /* inode */
+		.ust_mode    = src->st_mode,    /* protection */
+		.ust_nlink   = src->st_nlink,   /* number of hard links */
+		.ust_uid     = src->st_uid,     /* user ID of owner */
+		.ust_gid     = src->st_gid,     /* group ID of owner */
+		.ust_size    = src->st_size,    /* total size, in bytes */
+		.ust_blksize = src->st_blksize, /* blocksize for filesys I/O */
+		.ust_blocks  = src->st_blocks,  /* number of blocks allocated */
+		.ust_atime   = src->st_atime,   /* time of last access */
+		.ust_mtime   = src->st_mtime,   /* time of last modification */
+		.ust_ctime   = src->st_ctime,   /* time of last change */
+	});
+}
+
+int os_stat_fd(const int fd, struct uml_stat *ubuf)
+{
+	struct stat64 sbuf;
+	int err;
+
+	CATCH_EINTR(err = fstat64(fd, &sbuf));
+	if(err < 0)
+		return -errno;
+
+	if(ubuf != NULL)
+		copy_stat(ubuf, &sbuf);
+	return err;
+}
+
+int os_stat_file(const char *file_name, struct uml_stat *ubuf)
+{
+	struct stat64 sbuf;
+	int err;
+
+	do {
+		err = stat64(file_name, &sbuf);
+	} while((err < 0) && (errno == EINTR)) ;
+
+	if(err < 0)
+		return -errno;
+
+	if(ubuf != NULL)
+		copy_stat(ubuf, &sbuf);
+	return err;
+}
+
+int os_access(const char* file, int mode)
+{
+	int amode, err;
+
+	amode=(mode&OS_ACC_R_OK ? R_OK : 0) | (mode&OS_ACC_W_OK ? W_OK : 0) |
+	      (mode&OS_ACC_X_OK ? X_OK : 0) | (mode&OS_ACC_F_OK ? F_OK : 0) ;
+
+	err = access(file, amode);
+	if(err < 0)
+		return -errno;
+
+	return 0;
+}
+
+void os_print_error(int error, const char* str)
+{
+	errno = error < 0 ? -error : error;
+
+	perror(str);
+}
+
+/* FIXME? required only by hostaudio (because it passes ioctls verbatim) */
+int os_ioctl_generic(int fd, unsigned int cmd, unsigned long arg)
+{
+	int err;
+
+	err = ioctl(fd, cmd, arg);
+	if(err < 0)
+		return -errno;
+
+	return err;
+}
+
+int os_window_size(int fd, int *rows, int *cols)
+{
+	struct winsize size;
+
+	if(ioctl(fd, TIOCGWINSZ, &size) < 0)
+		return -errno;
+
+	*rows = size.ws_row;
+	*cols = size.ws_col;
+
+	return 0;
+}
+
+int os_new_tty_pgrp(int fd, int pid)
+{
+	if(ioctl(fd, TIOCSCTTY, 0) < 0)
+		return -errno;
+
+	if(tcsetpgrp(fd, pid) < 0)
+		return -errno;
+
+	return 0;
+}
+
+/* FIXME: ensure namebuf in os_get_if_name is big enough */
+int os_get_ifname(int fd, char* namebuf)
+{
+	if(ioctl(fd, SIOCGIFNAME, namebuf) < 0)
+		return -errno;
+
+	return 0;
+}
+
+int os_set_slip(int fd)
+{
+	int disc, sencap;
+
+	disc = N_SLIP;
+	if(ioctl(fd, TIOCSETD, &disc) < 0)
+		return -errno;
+
+	sencap = 0;
+	if(ioctl(fd, SIOCSIFENCAP, &sencap) < 0)
+		return -errno;
+
+	return 0;
+}
+
+int os_set_owner(int fd, int pid)
+{
+	if(fcntl(fd, F_SETOWN, pid) < 0){
+		int save_errno = errno;
+
+		if(fcntl(fd, F_GETOWN, 0) != pid)
+			return -save_errno;
+	}
+
+	return 0;
+}
+
+int os_mode_fd(int fd, int mode)
+{
+	int err;
+
+	do {
+		err = fchmod(fd, mode);
+	} while((err < 0) && (errno==EINTR)) ;
+
+	if(err < 0)
+		return -errno;
+
+	return 0;
+}
+
+int os_file_type(char *file)
+{
+	struct uml_stat buf;
+	int err;
+
+	err = os_stat_file(file, &buf);
+	if(err < 0)
+		return err;
+
+	if(S_ISDIR(buf.ust_mode))
+		return OS_TYPE_DIR;
+	else if(S_ISLNK(buf.ust_mode))
+		return OS_TYPE_SYMLINK;
+	else if(S_ISCHR(buf.ust_mode))
+		return OS_TYPE_CHARDEV;
+	else if(S_ISBLK(buf.ust_mode))
+		return OS_TYPE_BLOCKDEV;
+	else if(S_ISFIFO(buf.ust_mode))
+		return OS_TYPE_FIFO;
+	else if(S_ISSOCK(buf.ust_mode))
+		return OS_TYPE_SOCK;
+	else return OS_TYPE_FILE;
+}
+
+int os_file_mode(char *file, struct openflags *mode_out)
+{
+	int err;
+
+	*mode_out = OPENFLAGS();
+
+	err = os_access(file, OS_ACC_W_OK);
+	if((err < 0) && (err != -EACCES))
+		return(err);
+
+	*mode_out = of_write(*mode_out);
+
+	err = os_access(file, OS_ACC_R_OK);
+	if((err < 0) && (err != -EACCES))
+		return(err);
+
+	*mode_out = of_read(*mode_out);
+
+	return(0);
+}
+
+int os_open_file(char *file, struct openflags flags, int mode)
+{
+	int fd, err, f = 0;
+
+	if(flags.r && flags.w) f = O_RDWR;
+	else if(flags.r) f = O_RDONLY;
+	else if(flags.w) f = O_WRONLY;
+	else f = 0;
+
+	if(flags.s) f |= O_SYNC;
+	if(flags.c) f |= O_CREAT;
+	if(flags.t) f |= O_TRUNC;
+	if(flags.e) f |= O_EXCL;
+
+	fd = open64(file, f, mode);
+	if(fd < 0)
+		return(-errno);
+
+	if(flags.cl && fcntl(fd, F_SETFD, 1)){
+		err = -errno;
+		os_close_file(fd);
+		return err;
+	}
+
+	return(fd);
+}
+
+int os_connect_socket(char *name)
+{
+	struct sockaddr_un sock;
+	int fd, err;
+
+	sock.sun_family = AF_UNIX;
+	snprintf(sock.sun_path, sizeof(sock.sun_path), "%s", name);
+
+	fd = socket(AF_UNIX, SOCK_STREAM, 0);
+	if(fd < 0) {
+		err = -errno;
+		goto out;
+	}
+
+	err = connect(fd, (struct sockaddr *) &sock, sizeof(sock));
+	if(err) {
+		err = -errno;
+		goto out_close;
+	}
+
+	return fd;
+
+out_close:
+	close(fd);
+out:
+	return err;
+}
+
+void os_close_file(int fd)
+{
+	close(fd);
+}
+
+int os_seek_file(int fd, __u64 offset)
+{
+	__u64 actual;
+
+	actual = lseek64(fd, offset, SEEK_SET);
+	if(actual != offset)
+		return -errno;
+	return 0;
+}
+
+static int fault_buffer(void *start, int len,
+			int (*copy_proc)(void *addr, void *buf, int len))
+{
+	int page = getpagesize(), i;
+	char c;
+
+	for(i = 0; i < len; i += page){
+		if((*copy_proc)(start + i, &c, sizeof(c)))
+			return -EFAULT;
+	}
+	if((len % page) != 0){
+		if((*copy_proc)(start + len - 1, &c, sizeof(c)))
+			return -EFAULT;
+	}
+	return 0;
+}
+
+static int file_io(int fd, void *buf, int len,
+		   int (*io_proc)(int fd, void *buf, int len),
+		   int (*copy_user_proc)(void *addr, void *buf, int len))
+{
+	int n, err;
+
+	do {
+		n = (*io_proc)(fd, buf, len);
+		if((n < 0) && (errno == EFAULT)){
+			err = fault_buffer(buf, len, copy_user_proc);
+			if(err)
+				return err;
+			n = (*io_proc)(fd, buf, len);
+		}
+	} while((n < 0) && (errno == EINTR));
+
+	if(n < 0)
+		return -errno;
+	return n;
+}
+
+int os_read_file(int fd, void *buf, int len)
+{
+	return file_io(fd, buf, len, (int (*)(int, void *, int)) read,
+		       copy_from_user_proc);
+}
+
+int os_write_file(int fd, const void *buf, int len)
+{
+	return file_io(fd, (void *) buf, len,
+		       (int (*)(int, void *, int)) write, copy_to_user_proc);
+}
+
+int os_file_size(char *file, unsigned long long *size_out)
+{
+	struct uml_stat buf;
+	int err;
+
+	err = os_stat_file(file, &buf);
+	if(err < 0){
+		printk("Couldn't stat \"%s\" : err = %d\n", file, -err);
+		return(err);
+	}
+
+	if(S_ISBLK(buf.ust_mode)){
+		int fd, blocks;
+
+		fd = os_open_file(file, of_read(OPENFLAGS()), 0);
+		if(fd < 0){
+			printk("Couldn't open \"%s\", errno = %d\n", file, -fd);
+			return(fd);
+		}
+		if(ioctl(fd, BLKGETSIZE, &blocks) < 0){
+			err = -errno;
+			printk("Couldn't get the block size of \"%s\", "
+			       "errno = %d\n", file, errno);
+			os_close_file(fd);
+			return(err);
+		}
+		*size_out = ((long long) blocks) * 512;
+		os_close_file(fd);
+		return(0);
+	}
+	*size_out = buf.ust_size;
+	return(0);
+}
+
+int os_file_modtime(char *file, unsigned long *modtime)
+{
+	struct uml_stat buf;
+	int err;
+
+	err = os_stat_file(file, &buf);
+	if(err < 0){
+		printk("Couldn't stat \"%s\" : err = %d\n", file, -err);
+		return err;
+	}
+
+	*modtime = buf.ust_mtime;
+	return 0;
+}
+
+int os_get_exec_close(int fd, int* close_on_exec)
+{
+	int ret;
+
+	do {
+		ret = fcntl(fd, F_GETFD);
+	} while((ret < 0) && (errno == EINTR)) ;
+
+	if(ret < 0)
+		return(-errno);
+
+	*close_on_exec = (ret&FD_CLOEXEC) ? 1 : 0;
+	return(ret);
+}
+
+int os_set_exec_close(int fd, int close_on_exec)
+{
+	int flag, err;
+
+	if(close_on_exec) flag = FD_CLOEXEC;
+	else flag = 0;
+
+	do {
+		err = fcntl(fd, F_SETFD, flag);
+	} while((err < 0) && (errno == EINTR)) ;
+
+	if(err < 0)
+		return(-errno);
+	return(err);
+}
+
+int os_pipe(int *fds, int stream, int close_on_exec)
+{
+	int err, type = stream ? SOCK_STREAM : SOCK_DGRAM;
+
+	err = socketpair(AF_UNIX, type, 0, fds);
+	if(err < 0)
+		return(-errno);
+
+	if(!close_on_exec)
+		return(0);
+
+	err = os_set_exec_close(fds[0], 1);
+	if(err < 0)
+		goto error;
+
+	err = os_set_exec_close(fds[1], 1);
+	if(err < 0)
+		goto error;
+
+	return 0;
+
+ error:
+	printk("os_pipe : Setting FD_CLOEXEC failed, err = %d\n", -err);
+	os_close_file(fds[1]);
+	os_close_file(fds[0]);
+	return(err);
+}
+
+int os_set_fd_async(int fd, int owner)
+{
+	int err;
+
+	/* XXX This should do F_GETFL first */
+	if(fcntl(fd, F_SETFL, O_ASYNC | O_NONBLOCK) < 0){
+		err = -errno;
+		printk("os_set_fd_async : failed to set O_ASYNC and "
+		       "O_NONBLOCK on fd # %d, errno = %d\n", fd, errno);
+		return err;
+	}
+#ifdef notdef
+	if(fcntl(fd, F_SETFD, 1) < 0){
+		printk("os_set_fd_async : Setting FD_CLOEXEC failed, "
+		       "errno = %d\n", errno);
+	}
+#endif
+
+	if((fcntl(fd, F_SETSIG, SIGIO) < 0) ||
+	   (fcntl(fd, F_SETOWN, owner) < 0)){
+		err = -errno;
+		printk("os_set_fd_async : Failed to fcntl F_SETOWN "
+		       "(or F_SETSIG) fd %d to pid %d, errno = %d\n", fd,
+		       owner, errno);
+		return err;
+	}
+
+	return 0;
+}
+
+int os_clear_fd_async(int fd)
+{
+	int flags = fcntl(fd, F_GETFL);
+
+	flags &= ~(O_ASYNC | O_NONBLOCK);
+	if(fcntl(fd, F_SETFL, flags) < 0)
+		return -errno;
+	return 0;
+}
+
+int os_set_fd_block(int fd, int blocking)
+{
+	int flags;
+
+	flags = fcntl(fd, F_GETFL);
+
+	if(blocking) flags &= ~O_NONBLOCK;
+	else flags |= O_NONBLOCK;
+
+	if(fcntl(fd, F_SETFL, flags) < 0)
+		return -errno;
+
+	return 0;
+}
+
+int os_accept_connection(int fd)
+{
+	int new;
+
+	new = accept(fd, NULL, 0);
+	if(new < 0)
+		return -errno;
+	return new;
+}
+
+#ifndef SHUT_RD
+#define SHUT_RD 0
+#endif
+
+#ifndef SHUT_WR
+#define SHUT_WR 1
+#endif
+
+#ifndef SHUT_RDWR
+#define SHUT_RDWR 2
+#endif
+
+int os_shutdown_socket(int fd, int r, int w)
+{
+	int what, err;
+
+	if(r && w) what = SHUT_RDWR;
+	else if(r) what = SHUT_RD;
+	else if(w) what = SHUT_WR;
+	else {
+		printk("os_shutdown_socket : neither r or w was set\n");
+		return -EINVAL;
+	}
+	err = shutdown(fd, what);
+	if(err < 0)
+		return -errno;
+	return 0;
+}
+
+int os_rcv_fd(int fd, int *helper_pid_out)
+{
+	int new, n;
+	char buf[CMSG_SPACE(sizeof(new))];
+	struct msghdr msg;
+	struct cmsghdr *cmsg;
+	struct iovec iov;
+
+	msg.msg_name = NULL;
+	msg.msg_namelen = 0;
+	iov = ((struct iovec) { .iov_base  = helper_pid_out,
+				.iov_len   = sizeof(*helper_pid_out) });
+	msg.msg_iov = &iov;
+	msg.msg_iovlen = 1;
+	msg.msg_control = buf;
+	msg.msg_controllen = sizeof(buf);
+	msg.msg_flags = 0;
+
+	n = recvmsg(fd, &msg, 0);
+	if(n < 0)
+		return -errno;
+
+	else if(n != sizeof(iov.iov_len))
+		*helper_pid_out = -1;
+
+	cmsg = CMSG_FIRSTHDR(&msg);
+	if(cmsg == NULL){
+		printk("rcv_fd didn't receive anything, error = %d\n", errno);
+		return -1;
+	}
+	if((cmsg->cmsg_level != SOL_SOCKET) ||
+	   (cmsg->cmsg_type != SCM_RIGHTS)){
+		printk("rcv_fd didn't receive a descriptor\n");
+		return -1;
+	}
+
+	new = ((int *) CMSG_DATA(cmsg))[0];
+	return new;
+}
+
+int os_create_unix_socket(char *file, int len, int close_on_exec)
+{
+	struct sockaddr_un addr;
+	int sock, err;
+
+	sock = socket(PF_UNIX, SOCK_DGRAM, 0);
+	if(sock < 0)
+		return -errno;
+
+	if(close_on_exec) {
+		err = os_set_exec_close(sock, 1);
+		if(err < 0)
+			printk("create_unix_socket : close_on_exec failed, "
+		       "err = %d", -err);
+	}
+
+	addr.sun_family = AF_UNIX;
+
+	/* XXX Be more careful about overflow */
+	snprintf(addr.sun_path, len, "%s", file);
+
+	err = bind(sock, (struct sockaddr *) &addr, sizeof(addr));
+	if(err < 0)
+		return -errno;
+
+	return sock;
+}
+
+void os_flush_stdout(void)
+{
+	fflush(stdout);
+}
+
+int os_lock_file(int fd, int excl)
+{
+	int type = excl ? F_WRLCK : F_RDLCK;
+	struct flock lock = ((struct flock) { .l_type	= type,
+					      .l_whence	= SEEK_SET,
+					      .l_start	= 0,
+					      .l_len	= 0 } );
+	int err, save;
+
+	err = fcntl(fd, F_SETLK, &lock);
+	if(!err)
+		goto out;
+
+	save = -errno;
+	err = fcntl(fd, F_GETLK, &lock);
+	if(err){
+		err = -errno;
+		goto out;
+	}
+
+	printk("F_SETLK failed, file already locked by pid %d\n", lock.l_pid);
+	err = save;
+ out:
+	return err;
+}

arch/um/os-Linux/helper.c

@@ -0,0 +1,173 @@
+/*
+ * Copyright (C) 2002 Jeff Dike (jdike@karaya.com)
+ * Licensed under the GPL
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <errno.h>
+#include <sched.h>
+#include <limits.h>
+#include <sys/signal.h>
+#include <sys/wait.h>
+#include "user.h"
+#include "kern_util.h"
+#include "user_util.h"
+#include "os.h"
+#include "um_malloc.h"
+
+struct helper_data {
+	void (*pre_exec)(void*);
+	void *pre_data;
+	char **argv;
+	int fd;
+	char *buf;
+};
+
+/* Debugging aid, changed only from gdb */
+int helper_pause = 0;
+
+static void helper_hup(int sig)
+{
+}
+
+static int helper_child(void *arg)
+{
+	struct helper_data *data = arg;
+	char **argv = data->argv;
+	int errval;
+
+	if (helper_pause){
+		signal(SIGHUP, helper_hup);
+		pause();
+	}
+	if (data->pre_exec != NULL)
+		(*data->pre_exec)(data->pre_data);
+	errval = execvp_noalloc(data->buf, argv[0], argv);
+	printk("helper_child - execvp of '%s' failed - errno = %d\n", argv[0], -errval);
+	os_write_file(data->fd, &errval, sizeof(errval));
+	kill(os_getpid(), SIGKILL);
+	return 0;
+}
+
+/* Returns either the pid of the child process we run or -E* on failure.
+ * XXX The alloc_stack here breaks if this is called in the tracing thread, so
+ * we need to receive a preallocated stack (a local buffer is ok). */
+int run_helper(void (*pre_exec)(void *), void *pre_data, char **argv,
+	       unsigned long *stack_out)
+{
+	struct helper_data data;
+	unsigned long stack, sp;
+	int pid, fds[2], ret, n;
+
+	if ((stack_out != NULL) && (*stack_out != 0))
+		stack = *stack_out;
+	else
+		stack = alloc_stack(0, __cant_sleep());
+	if (stack == 0)
+		return -ENOMEM;
+
+	ret = os_pipe(fds, 1, 0);
+	if (ret < 0) {
+		printk("run_helper : pipe failed, ret = %d\n", -ret);
+		goto out_free;
+	}
+
+	ret = os_set_exec_close(fds[1], 1);
+	if (ret < 0) {
+		printk("run_helper : setting FD_CLOEXEC failed, ret = %d\n",
+		       -ret);
+		goto out_close;
+	}
+
+	sp = stack + page_size() - sizeof(void *);
+	data.pre_exec = pre_exec;
+	data.pre_data = pre_data;
+	data.argv = argv;
+	data.fd = fds[1];
+	data.buf = __cant_sleep() ? um_kmalloc_atomic(PATH_MAX) :
+					um_kmalloc(PATH_MAX);
+	pid = clone(helper_child, (void *) sp, CLONE_VM | SIGCHLD, &data);
+	if (pid < 0) {
+		ret = -errno;
+		printk("run_helper : clone failed, errno = %d\n", errno);
+		goto out_free2;
+	}
+
+	close(fds[1]);
+	fds[1] = -1;
+
+	/* Read the errno value from the child, if the exec failed, or get 0 if
+	 * the exec succeeded because the pipe fd was set as close-on-exec. */
+	n = os_read_file(fds[0], &ret, sizeof(ret));
+	if (n == 0) {
+		ret = pid;
+	} else {
+		if (n < 0) {
+			printk("run_helper : read on pipe failed, ret = %d\n",
+			       -n);
+			ret = n;
+			kill(pid, SIGKILL);
+		}
+		CATCH_EINTR(waitpid(pid, NULL, 0));
+	}
+
+out_free2:
+	kfree(data.buf);
+out_close:
+	if (fds[1] != -1)
+		close(fds[1]);
+	close(fds[0]);
+out_free:
+	if ((stack_out == NULL) || (*stack_out == 0))
+		free_stack(stack, 0);
+	return ret;
+}
+
+int run_helper_thread(int (*proc)(void *), void *arg, unsigned int flags,
+		      unsigned long *stack_out, int stack_order)
+{
+	unsigned long stack, sp;
+	int pid, status, err;
+
+	stack = alloc_stack(stack_order, __cant_sleep());
+	if (stack == 0)
+		return -ENOMEM;
+
+	sp = stack + (page_size() << stack_order) - sizeof(void *);
+	pid = clone(proc, (void *) sp, flags | SIGCHLD, arg);
+	if (pid < 0) {
+		err = -errno;
+		printk("run_helper_thread : clone failed, errno = %d\n",
+		       errno);
+		return err;
+	}
+	if (stack_out == NULL) {
+		CATCH_EINTR(pid = waitpid(pid, &status, 0));
+		if (pid < 0) {
+			err = -errno;
+			printk("run_helper_thread - wait failed, errno = %d\n",
+			       errno);
+			pid = err;
+		}
+		if (!WIFEXITED(status) || (WEXITSTATUS(status) != 0))
+			printk("run_helper_thread - thread returned status "
+			       "0x%x\n", status);
+		free_stack(stack, stack_order);
+	} else
+		*stack_out = stack;
+	return pid;
+}
+
+int helper_wait(int pid)
+{
+	int ret;
+
+	CATCH_EINTR(ret = waitpid(pid, NULL, WNOHANG));
+	if (ret < 0) {
+		ret = -errno;
+		printk("helper_wait : waitpid failed, errno = %d\n", errno);
+	}
+	return ret;
+}

arch/um/os-Linux/include/file.h

@@ -0,0 +1,22 @@
+/* 
+ * Copyright (C) 2002 Jeff Dike (jdike@karaya.com)
+ * Licensed under the GPL
+ */
+
+#ifndef __OS_FILE_H__
+#define __OS_FILE_H__
+
+#define DEV_NULL "/dev/null"
+
+#endif
+
+/*
+ * Overrides for Emacs so that we follow Linus's tabbing style.
+ * Emacs will notice this stuff at the end of the file and automatically
+ * adjust the settings for this buffer only.  This must remain at the end
+ * of the file.
+ * ---------------------------------------------------------------------------
+ * Local variables:
+ * c-file-style: "linux"
+ * End:
+ */

arch/um/os-Linux/irq.c

@@ -0,0 +1,156 @@
+/*
+ * Copyright (C) 2000, 2001, 2002 Jeff Dike (jdike@karaya.com)
+ * Licensed under the GPL
+ */
+
+#include <stdlib.h>
+#include <unistd.h>
+#include <errno.h>
+#include <signal.h>
+#include <string.h>
+#include <sys/poll.h>
+#include <sys/types.h>
+#include <sys/time.h>
+#include "user_util.h"
+#include "kern_util.h"
+#include "user.h"
+#include "process.h"
+#include "sigio.h"
+#include "irq_user.h"
+#include "os.h"
+#include "um_malloc.h"
+
+/*
+ * Locked by irq_lock in arch/um/kernel/irq.c.  Changed by os_create_pollfd
+ * and os_free_irq_by_cb, which are called under irq_lock.
+ */
+static struct pollfd *pollfds = NULL;
+static int pollfds_num = 0;
+static int pollfds_size = 0;
+
+int os_waiting_for_events(struct irq_fd *active_fds)
+{
+	struct irq_fd *irq_fd;
+	int i, n, err;
+
+	n = poll(pollfds, pollfds_num, 0);
+	if (n < 0) {
+		err = -errno;
+		if (errno != EINTR)
+			printk("sigio_handler: os_waiting_for_events:"
+			       " poll returned %d, errno = %d\n", n, errno);
+		return err;
+	}
+
+	if (n == 0)
+		return 0;
+
+	irq_fd = active_fds;
+
+	for (i = 0; i < pollfds_num; i++) {
+		if (pollfds[i].revents != 0) {
+			irq_fd->current_events = pollfds[i].revents;
+			pollfds[i].fd = -1;
+		}
+		irq_fd = irq_fd->next;
+	}
+	return n;
+}
+
+int os_create_pollfd(int fd, int events, void *tmp_pfd, int size_tmpfds)
+{
+	if (pollfds_num == pollfds_size) {
+		if (size_tmpfds <= pollfds_size * sizeof(pollfds[0])) {
+			/* return min size needed for new pollfds area */
+			return (pollfds_size + 1) * sizeof(pollfds[0]);
+		}
+
+		if (pollfds != NULL) {
+			memcpy(tmp_pfd, pollfds,
+			       sizeof(pollfds[0]) * pollfds_size);
+			/* remove old pollfds */
+			kfree(pollfds);
+		}
+		pollfds = tmp_pfd;
+		pollfds_size++;
+	} else
+		kfree(tmp_pfd);	/* remove not used tmp_pfd */
+
+	pollfds[pollfds_num] = ((struct pollfd) { .fd		= fd,
+						  .events	= events,
+						  .revents	= 0 });
+	pollfds_num++;
+
+	return 0;
+}
+
+void os_free_irq_by_cb(int (*test)(struct irq_fd *, void *), void *arg,
+		struct irq_fd *active_fds, struct irq_fd ***last_irq_ptr2)
+{
+	struct irq_fd **prev;
+	int i = 0;
+
+	prev = &active_fds;
+	while (*prev != NULL) {
+		if ((*test)(*prev, arg)) {
+			struct irq_fd *old_fd = *prev;
+			if ((pollfds[i].fd != -1) &&
+			    (pollfds[i].fd != (*prev)->fd)) {
+				printk("os_free_irq_by_cb - mismatch between "
+				       "active_fds and pollfds, fd %d vs %d\n",
+				       (*prev)->fd, pollfds[i].fd);
+				goto out;
+			}
+
+			pollfds_num--;
+
+			/* This moves the *whole* array after pollfds[i]
+			 * (though it doesn't spot as such)!
+			 */
+			memmove(&pollfds[i], &pollfds[i + 1],
+			       (pollfds_num - i) * sizeof(pollfds[0]));
+			if(*last_irq_ptr2 == &old_fd->next)
+				*last_irq_ptr2 = prev;
+
+			*prev = (*prev)->next;
+			if(old_fd->type == IRQ_WRITE)
+				ignore_sigio_fd(old_fd->fd);
+			kfree(old_fd);
+			continue;
+		}
+		prev = &(*prev)->next;
+		i++;
+	}
+ out:
+	return;
+}
+
+int os_get_pollfd(int i)
+{
+	return pollfds[i].fd;
+}
+
+void os_set_pollfd(int i, int fd)
+{
+	pollfds[i].fd = fd;
+}
+
+void os_set_ioignore(void)
+{
+	signal(SIGIO, SIG_IGN);
+}
+
+void init_irq_signals(int on_sigstack)
+{
+	int flags;
+
+	flags = on_sigstack ? SA_ONSTACK : 0;
+
+	set_handler(SIGVTALRM, (__sighandler_t) alarm_handler,
+		    flags | SA_RESTART, SIGUSR1, SIGIO, SIGWINCH, SIGALRM, -1);
+	set_handler(SIGALRM, (__sighandler_t) alarm_handler,
+		    flags | SA_RESTART, SIGUSR1, SIGIO, SIGWINCH, SIGALRM, -1);
+	set_handler(SIGIO, (__sighandler_t) sig_handler, flags | SA_RESTART,
+		    SIGUSR1, SIGIO, SIGWINCH, SIGALRM, SIGVTALRM, -1);
+	signal(SIGWINCH, SIG_IGN);
+}

arch/um/os-Linux/main.c

@@ -0,0 +1,298 @@
+/*
+ * Copyright (C) 2000, 2001 Jeff Dike (jdike@karaya.com)
+ * Licensed under the GPL
+ */
+
+#include <unistd.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <signal.h>
+#include <errno.h>
+#include <sys/resource.h>
+#include <sys/mman.h>
+#include <sys/user.h>
+#include <asm/page.h>
+#include "user_util.h"
+#include "kern_util.h"
+#include "mem_user.h"
+#include "irq_user.h"
+#include "user.h"
+#include "init.h"
+#include "mode.h"
+#include "choose-mode.h"
+#include "uml-config.h"
+#include "os.h"
+#include "um_malloc.h"
+
+/* Set in set_stklim, which is called from main and __wrap_malloc.
+ * __wrap_malloc only calls it if main hasn't started.
+ */
+unsigned long stacksizelim;
+
+/* Set in main */
+char *linux_prog;
+
+#define PGD_BOUND (4 * 1024 * 1024)
+#define STACKSIZE (8 * 1024 * 1024)
+#define THREAD_NAME_LEN (256)
+
+static void set_stklim(void)
+{
+	struct rlimit lim;
+
+	if(getrlimit(RLIMIT_STACK, &lim) < 0){
+		perror("getrlimit");
+		exit(1);
+	}
+	if((lim.rlim_cur == RLIM_INFINITY) || (lim.rlim_cur > STACKSIZE)){
+		lim.rlim_cur = STACKSIZE;
+		if(setrlimit(RLIMIT_STACK, &lim) < 0){
+			perror("setrlimit");
+			exit(1);
+		}
+	}
+	stacksizelim = (lim.rlim_cur + PGD_BOUND - 1) & ~(PGD_BOUND - 1);
+}
+
+static __init void do_uml_initcalls(void)
+{
+	initcall_t *call;
+
+	call = &__uml_initcall_start;
+	while (call < &__uml_initcall_end){
+		(*call)();
+		call++;
+	}
+}
+
+static void last_ditch_exit(int sig)
+{
+	uml_cleanup();
+	exit(1);
+}
+
+static void install_fatal_handler(int sig)
+{
+	struct sigaction action;
+
+	/* All signals are enabled in this handler ... */
+	sigemptyset(&action.sa_mask);
+
+	/* ... including the signal being handled, plus we want the
+	 * handler reset to the default behavior, so that if an exit
+	 * handler is hanging for some reason, the UML will just die
+	 * after this signal is sent a second time.
+	 */
+	action.sa_flags = SA_RESETHAND | SA_NODEFER;
+	action.sa_restorer = NULL;
+	action.sa_handler = last_ditch_exit;
+	if(sigaction(sig, &action, NULL) < 0){
+		printf("failed to install handler for signal %d - errno = %d\n",
+		       errno);
+		exit(1);
+	}
+}
+
+#define UML_LIB_PATH	":/usr/lib/uml"
+
+static void setup_env_path(void)
+{
+	char *new_path = NULL;
+	char *old_path = NULL;
+	int path_len = 0;
+
+	old_path = getenv("PATH");
+	/* if no PATH variable is set or it has an empty value
+	 * just use the default + /usr/lib/uml
+	 */
+	if (!old_path || (path_len = strlen(old_path)) == 0) {
+		putenv("PATH=:/bin:/usr/bin/" UML_LIB_PATH);
+		return;
+	}
+
+	/* append /usr/lib/uml to the existing path */
+	path_len += strlen("PATH=" UML_LIB_PATH) + 1;
+	new_path = malloc(path_len);
+	if (!new_path) {
+		perror("coudn't malloc to set a new PATH");
+		return;
+	}
+	snprintf(new_path, path_len, "PATH=%s" UML_LIB_PATH, old_path);
+	putenv(new_path);
+}
+
+extern int uml_exitcode;
+
+extern void scan_elf_aux( char **envp);
+
+int main(int argc, char **argv, char **envp)
+{
+	char **new_argv;
+	int ret, i, err;
+
+#ifdef UML_CONFIG_CMDLINE_ON_HOST
+	/* Allocate memory for thread command lines */
+	if(argc < 2 || strlen(argv[1]) < THREAD_NAME_LEN - 1){
+
+		char padding[THREAD_NAME_LEN] = {
+			[ 0 ...  THREAD_NAME_LEN - 2] = ' ', '\0'
+		};
+
+		new_argv = malloc((argc + 2) * sizeof(char*));
+		if(!new_argv) {
+			perror("Allocating extended argv");
+			exit(1);
+		}
+
+		new_argv[0] = argv[0];
+		new_argv[1] = padding;
+
+		for(i = 2; i <= argc; i++)
+			new_argv[i] = argv[i - 1];
+		new_argv[argc + 1] = NULL;
+
+		execvp(new_argv[0], new_argv);
+		perror("execing with extended args");
+		exit(1);
+	}
+#endif
+
+	linux_prog = argv[0];
+
+	set_stklim();
+
+	setup_env_path();
+
+	new_argv = malloc((argc + 1) * sizeof(char *));
+	if(new_argv == NULL){
+		perror("Mallocing argv");
+		exit(1);
+	}
+	for(i=0;i<argc;i++){
+		new_argv[i] = strdup(argv[i]);
+		if(new_argv[i] == NULL){
+			perror("Mallocing an arg");
+			exit(1);
+		}
+	}
+	new_argv[argc] = NULL;
+
+	/* Allow these signals to bring down a UML if all other
+	 * methods of control fail.
+	 */
+	install_fatal_handler(SIGINT);
+	install_fatal_handler(SIGTERM);
+	install_fatal_handler(SIGHUP);
+
+	scan_elf_aux( envp);
+
+	do_uml_initcalls();
+	ret = linux_main(argc, argv);
+
+	/* Disable SIGPROF - I have no idea why libc doesn't do this or turn
+	 * off the profiling time, but UML dies with a SIGPROF just before
+	 * exiting when profiling is active.
+	 */
+	change_sig(SIGPROF, 0);
+
+	/* This signal stuff used to be in the reboot case.  However,
+	 * sometimes a SIGVTALRM can come in when we're halting (reproducably
+	 * when writing out gcov information, presumably because that takes
+	 * some time) and cause a segfault.
+	 */
+
+	/* stop timers and set SIG*ALRM to be ignored */
+	disable_timer();
+
+	/* disable SIGIO for the fds and set SIGIO to be ignored */
+	err = deactivate_all_fds();
+	if(err)
+		printf("deactivate_all_fds failed, errno = %d\n", -err);
+
+	/* Let any pending signals fire now.  This ensures
+	 * that they won't be delivered after the exec, when
+	 * they are definitely not expected.
+	 */
+	unblock_signals();
+
+	/* Reboot */
+	if(ret){
+		printf("\n");
+		execvp(new_argv[0], new_argv);
+		perror("Failed to exec kernel");
+		ret = 1;
+	}
+	printf("\n");
+	return(uml_exitcode);
+}
+
+#define CAN_KMALLOC() \
+	(kmalloc_ok && CHOOSE_MODE((os_getpid() != tracing_pid), 1))
+
+extern void *__real_malloc(int);
+
+void *__wrap_malloc(int size)
+{
+	void *ret;
+
+	if(!CAN_KMALLOC())
+		return(__real_malloc(size));
+	else if(size <= PAGE_SIZE) /* finding contiguos pages can be hard*/
+		ret = um_kmalloc(size);
+	else ret = um_vmalloc(size);
+
+	/* glibc people insist that if malloc fails, errno should be
+	 * set by malloc as well. So we do.
+	 */
+	if(ret == NULL)
+		errno = ENOMEM;
+
+	return(ret);
+}
+
+void *__wrap_calloc(int n, int size)
+{
+	void *ptr = __wrap_malloc(n * size);
+
+	if(ptr == NULL) return(NULL);
+	memset(ptr, 0, n * size);
+	return(ptr);
+}
+
+extern void __real_free(void *);
+
+extern unsigned long high_physmem;
+
+void __wrap_free(void *ptr)
+{
+	unsigned long addr = (unsigned long) ptr;
+
+	/* We need to know how the allocation happened, so it can be correctly
+	 * freed.  This is done by seeing what region of memory the pointer is
+	 * in -
+	 * 	physical memory - kmalloc/kfree
+	 *	kernel virtual memory - vmalloc/vfree
+	 * 	anywhere else - malloc/free
+	 * If kmalloc is not yet possible, then either high_physmem and/or
+	 * end_vm are still 0 (as at startup), in which case we call free, or
+	 * we have set them, but anyway addr has not been allocated from those
+	 * areas. So, in both cases __real_free is called.
+	 *
+	 * CAN_KMALLOC is checked because it would be bad to free a buffer
+	 * with kmalloc/vmalloc after they have been turned off during
+	 * shutdown.
+	 * XXX: However, we sometimes shutdown CAN_KMALLOC temporarily, so
+	 * there is a possibility for memory leaks.
+	 */
+
+	if((addr >= uml_physmem) && (addr < high_physmem)){
+		if(CAN_KMALLOC())
+			kfree(ptr);
+	}
+	else if((addr >= start_vm) && (addr < end_vm)){
+		if(CAN_KMALLOC())
+			vfree(ptr);
+	}
+	else __real_free(ptr);
+}

arch/um/os-Linux/mem.c

@@ -0,0 +1,280 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <stddef.h>
+#include <stdarg.h>
+#include <unistd.h>
+#include <errno.h>
+#include <string.h>
+#include <fcntl.h>
+#include <sys/types.h>
+#include <sys/mman.h>
+#include <sys/statfs.h>
+#include "kern_util.h"
+#include "user.h"
+#include "user_util.h"
+#include "mem_user.h"
+#include "init.h"
+#include "os.h"
+#include "tempfile.h"
+#include "kern_constants.h"
+
+#include <sys/param.h>
+
+/* Modified by which_tmpdir, which is called during early boot */
+static char *default_tmpdir = "/tmp";
+
+/*
+ *  Modified when creating the physical memory file and when checking
+ * the tmp filesystem for usability, both happening during early boot.
+ */
+static char *tempdir = NULL;
+
+static void __init find_tempdir(void)
+{
+	char *dirs[] = { "TMP", "TEMP", "TMPDIR", NULL };
+	int i;
+	char *dir = NULL;
+
+	if(tempdir != NULL) /* We've already been called */
+		return;
+	for(i = 0; dirs[i]; i++){
+		dir = getenv(dirs[i]);
+		if((dir != NULL) && (*dir != '\0'))
+			break;
+	}
+	if((dir == NULL) || (*dir == '\0'))
+		dir = default_tmpdir;
+
+	tempdir = malloc(strlen(dir) + 2);
+	if(tempdir == NULL){
+		fprintf(stderr, "Failed to malloc tempdir, "
+			"errno = %d\n", errno);
+		return;
+	}
+	strcpy(tempdir, dir);
+	strcat(tempdir, "/");
+}
+
+/* This will return 1, with the first character in buf being the
+ * character following the next instance of c in the file.  This will
+ * read the file as needed.  If there's an error, -errno is returned;
+ * if the end of the file is reached, 0 is returned.
+ */
+static int next(int fd, char *buf, int size, char c)
+{
+	int n, len;
+	char *ptr;
+
+	while((ptr = strchr(buf, c)) == NULL){
+		n = read(fd, buf, size - 1);
+		if(n == 0)
+			return 0;
+		else if(n < 0)
+			return -errno;
+
+		buf[n] = '\0';
+	}
+
+	ptr++;
+	len = strlen(ptr);
+	memmove(buf, ptr, len + 1);
+
+	/* Refill the buffer so that if there's a partial string that we care
+	 * about, it will be completed, and we can recognize it.
+	 */
+	n = read(fd, &buf[len], size - len - 1);
+	if(n < 0)
+		return -errno;
+
+	buf[len + n] = '\0';
+	return 1;
+}
+
+/* which_tmpdir is called only during early boot */
+static int checked_tmpdir = 0;
+
+/* Look for a tmpfs mounted at /dev/shm.  I couldn't find a cleaner
+ * way to do this than to parse /proc/mounts.  statfs will return the
+ * same filesystem magic number and fs id for both /dev and /dev/shm
+ * when they are both tmpfs, so you can't tell if they are different
+ * filesystems.  Also, there seems to be no other way of finding the
+ * mount point of a filesystem from within it.
+ *
+ * If a /dev/shm tmpfs entry is found, then we switch to using it.
+ * Otherwise, we stay with the default /tmp.
+ */
+static void which_tmpdir(void)
+{
+	int fd, found;
+	char buf[128] = { '\0' };
+
+	if(checked_tmpdir)
+		return;
+
+	checked_tmpdir = 1;
+
+	printf("Checking for tmpfs mount on /dev/shm...");
+
+	fd = open("/proc/mounts", O_RDONLY);
+	if(fd < 0){
+		printf("failed to open /proc/mounts, errno = %d\n", errno);
+		return;
+	}
+
+	while(1){
+		found = next(fd, buf, ARRAY_SIZE(buf), ' ');
+		if(found != 1)
+			break;
+
+		if(!strncmp(buf, "/dev/shm", strlen("/dev/shm")))
+			goto found;
+
+		found = next(fd, buf, ARRAY_SIZE(buf), '\n');
+		if(found != 1)
+			break;
+	}
+
+err:
+	if(found == 0)
+		printf("nothing mounted on /dev/shm\n");
+	else if(found < 0)
+		printf("read returned errno %d\n", -found);
+
+out:
+	close(fd);
+
+	return;
+
+found:
+	found = next(fd, buf, ARRAY_SIZE(buf), ' ');
+	if(found != 1)
+		goto err;
+
+	if(strncmp(buf, "tmpfs", strlen("tmpfs"))){
+		printf("not tmpfs\n");
+		goto out;
+	}
+
+	printf("OK\n");
+	default_tmpdir = "/dev/shm";
+	goto out;
+}
+
+/*
+ * This proc still used in tt-mode
+ * (file: kernel/tt/ptproxy/proxy.c, proc: start_debugger).
+ * So it isn't 'static' yet.
+ */
+int make_tempfile(const char *template, char **out_tempname, int do_unlink)
+{
+	char *tempname;
+	int fd;
+
+	which_tmpdir();
+	tempname = malloc(MAXPATHLEN);
+
+	find_tempdir();
+	if (template[0] != '/')
+		strcpy(tempname, tempdir);
+	else
+		tempname[0] = '\0';
+	strcat(tempname, template);
+	fd = mkstemp(tempname);
+	if(fd < 0){
+		fprintf(stderr, "open - cannot create %s: %s\n", tempname,
+			strerror(errno));
+		goto out;
+	}
+	if(do_unlink && (unlink(tempname) < 0)){
+		perror("unlink");
+		goto out;
+	}
+	if(out_tempname){
+		*out_tempname = tempname;
+	} else {
+		free(tempname);
+	}
+	return fd;
+out:
+	free(tempname);
+	return -1;
+}
+
+#define TEMPNAME_TEMPLATE "vm_file-XXXXXX"
+
+/*
+ * This proc is used in start_up.c
+ * So it isn't 'static'.
+ */
+int create_tmp_file(unsigned long long len)
+{
+	int fd, err;
+	char zero;
+
+	fd = make_tempfile(TEMPNAME_TEMPLATE, NULL, 1);
+	if(fd < 0) {
+		exit(1);
+	}
+
+	err = fchmod(fd, 0777);
+	if(err < 0){
+		perror("os_mode_fd");
+		exit(1);
+	}
+
+	/* Seek to len - 1 because writing a character there will
+	 * increase the file size by one byte, to the desired length.
+	 */
+	if (lseek64(fd, len - 1, SEEK_SET) < 0) {
+		perror("os_seek_file");
+		exit(1);
+	}
+
+	zero = 0;
+
+	err = os_write_file(fd, &zero, 1);
+	if(err != 1){
+		errno = -err;
+		perror("os_write_file");
+		exit(1);
+	}
+
+	return fd;
+}
+
+int create_mem_file(unsigned long long len)
+{
+	int err, fd;
+
+	fd = create_tmp_file(len);
+
+	err = os_set_exec_close(fd, 1);
+	if(err < 0){
+		errno = -err;
+		perror("exec_close");
+	}
+	return fd;
+}
+
+
+void check_tmpexec(void)
+{
+	void *addr;
+	int err, fd = create_tmp_file(UM_KERN_PAGE_SIZE);
+
+	addr = mmap(NULL, UM_KERN_PAGE_SIZE,
+		    PROT_READ | PROT_WRITE | PROT_EXEC, MAP_PRIVATE, fd, 0);
+	printf("Checking PROT_EXEC mmap in %s...",tempdir);
+	fflush(stdout);
+	if(addr == MAP_FAILED){
+		err = errno;
+		perror("failed");
+		if(err == EPERM)
+			printf("%s must be not mounted noexec\n",tempdir);
+		exit(1);
+	}
+	printf("OK\n");
+	munmap(addr, UM_KERN_PAGE_SIZE);
+
+	close(fd);
+}

arch/um/os-Linux/process.c

@@ -0,0 +1,294 @@
+/* 
+ * Copyright (C) 2002 Jeff Dike (jdike@addtoit.com)
+ * Licensed under the GPL
+ */
+
+#include <unistd.h>
+#include <stdio.h>
+#include <errno.h>
+#include <signal.h>
+#include <sys/mman.h>
+#include <sys/wait.h>
+#include <sys/mman.h>
+#include <sys/syscall.h>
+#include "ptrace_user.h"
+#include "os.h"
+#include "user.h"
+#include "user_util.h"
+#include "process.h"
+#include "irq_user.h"
+#include "kern_util.h"
+#include "longjmp.h"
+#include "skas_ptrace.h"
+#include "kern_constants.h"
+#include "uml-config.h"
+
+#define ARBITRARY_ADDR -1
+#define FAILURE_PID    -1
+
+#define STAT_PATH_LEN sizeof("/proc/#######/stat\0")
+#define COMM_SCANF "%*[^)])"
+
+unsigned long os_process_pc(int pid)
+{
+	char proc_stat[STAT_PATH_LEN], buf[256];
+	unsigned long pc;
+	int fd, err;
+
+	sprintf(proc_stat, "/proc/%d/stat", pid);
+	fd = os_open_file(proc_stat, of_read(OPENFLAGS()), 0);
+	if(fd < 0){
+		printk("os_process_pc - couldn't open '%s', err = %d\n",
+		       proc_stat, -fd);
+		return(ARBITRARY_ADDR);
+	}
+	err = os_read_file(fd, buf, sizeof(buf));
+	if(err < 0){
+		printk("os_process_pc - couldn't read '%s', err = %d\n",
+		       proc_stat, -err);
+		os_close_file(fd);
+		return(ARBITRARY_ADDR);
+	}
+	os_close_file(fd);
+	pc = ARBITRARY_ADDR;
+	if(sscanf(buf, "%*d " COMM_SCANF " %*c %*d %*d %*d %*d %*d %*d %*d "
+		  "%*d %*d %*d %*d %*d %*d %*d %*d %*d %*d %*d %*d %*d %*d "
+		  "%*d %*d %*d %*d %*d %lu", &pc) != 1){
+		printk("os_process_pc - couldn't find pc in '%s'\n", buf);
+	}
+	return(pc);
+}
+
+int os_process_parent(int pid)
+{
+	char stat[STAT_PATH_LEN];
+	char data[256];
+	int parent, n, fd;
+
+	if(pid == -1) return(-1);
+
+	snprintf(stat, sizeof(stat), "/proc/%d/stat", pid);
+	fd = os_open_file(stat, of_read(OPENFLAGS()), 0);
+	if(fd < 0){
+		printk("Couldn't open '%s', err = %d\n", stat, -fd);
+		return(FAILURE_PID);
+	}
+
+	n = os_read_file(fd, data, sizeof(data));
+	os_close_file(fd);
+
+	if(n < 0){
+		printk("Couldn't read '%s', err = %d\n", stat, -n);
+		return(FAILURE_PID);
+	}
+
+	parent = FAILURE_PID;
+	n = sscanf(data, "%*d " COMM_SCANF " %*c %d", &parent);
+	if(n != 1)
+		printk("Failed to scan '%s'\n", data);
+
+	return(parent);
+}
+
+void os_stop_process(int pid)
+{
+	kill(pid, SIGSTOP);
+}
+
+void os_kill_process(int pid, int reap_child)
+{
+	kill(pid, SIGKILL);
+	if(reap_child)
+		CATCH_EINTR(waitpid(pid, NULL, 0));
+		
+}
+
+/* This is here uniquely to have access to the userspace errno, i.e. the one
+ * used by ptrace in case of error.
+ */
+
+long os_ptrace_ldt(long pid, long addr, long data)
+{
+	int ret;
+
+	ret = ptrace(PTRACE_LDT, pid, addr, data);
+
+	if (ret < 0)
+		return -errno;
+	return ret;
+}
+
+/* Kill off a ptraced child by all means available.  kill it normally first,
+ * then PTRACE_KILL it, then PTRACE_CONT it in case it's in a run state from
+ * which it can't exit directly.
+ */
+
+void os_kill_ptraced_process(int pid, int reap_child)
+{
+	kill(pid, SIGKILL);
+	ptrace(PTRACE_KILL, pid);
+	ptrace(PTRACE_CONT, pid);
+	if(reap_child)
+		CATCH_EINTR(waitpid(pid, NULL, 0));
+}
+
+#ifdef UML_CONFIG_MODE_TT
+void os_usr1_process(int pid)
+{
+	kill(pid, SIGUSR1);
+}
+#endif
+
+/* Don't use the glibc version, which caches the result in TLS. It misses some
+ * syscalls, and also breaks with clone(), which does not unshare the TLS.
+ */
+
+int os_getpid(void)
+{
+	return(syscall(__NR_getpid));
+}
+
+int os_getpgrp(void)
+{
+	return getpgrp();
+}
+
+int os_map_memory(void *virt, int fd, unsigned long long off, unsigned long len,
+		  int r, int w, int x)
+{
+	void *loc;
+	int prot;
+
+	prot = (r ? PROT_READ : 0) | (w ? PROT_WRITE : 0) | 
+		(x ? PROT_EXEC : 0);
+
+	loc = mmap64((void *) virt, len, prot, MAP_SHARED | MAP_FIXED,
+		     fd, off);
+	if(loc == MAP_FAILED)
+		return(-errno);
+	return(0);
+}
+
+int os_protect_memory(void *addr, unsigned long len, int r, int w, int x)
+{
+        int prot = ((r ? PROT_READ : 0) | (w ? PROT_WRITE : 0) | 
+		    (x ? PROT_EXEC : 0));
+
+        if(mprotect(addr, len, prot) < 0)
+		return(-errno);
+        return(0);
+}
+
+int os_unmap_memory(void *addr, int len)
+{
+        int err;
+
+        err = munmap(addr, len);
+	if(err < 0)
+		return(-errno);
+        return(0);
+}
+
+#ifndef MADV_REMOVE
+#define MADV_REMOVE KERNEL_MADV_REMOVE
+#endif
+
+int os_drop_memory(void *addr, int length)
+{
+	int err;
+
+	err = madvise(addr, length, MADV_REMOVE);
+	if(err < 0)
+		err = -errno;
+	return err;
+}
+
+int can_drop_memory(void)
+{
+	void *addr;
+	int fd, ok = 0;
+
+	printk("Checking host MADV_REMOVE support...");
+	fd = create_mem_file(UM_KERN_PAGE_SIZE);
+	if(fd < 0){
+		printk("Creating test memory file failed, err = %d\n", -fd);
+		goto out;
+	}
+
+	addr = mmap64(NULL, UM_KERN_PAGE_SIZE, PROT_READ | PROT_WRITE,
+		      MAP_SHARED, fd, 0);
+	if(addr == MAP_FAILED){
+		printk("Mapping test memory file failed, err = %d\n", -errno);
+		goto out_close;
+	}
+
+	if(madvise(addr, UM_KERN_PAGE_SIZE, MADV_REMOVE) != 0){
+		printk("MADV_REMOVE failed, err = %d\n", -errno);
+		goto out_unmap;
+	}
+
+	printk("OK\n");
+	ok = 1;
+
+out_unmap:
+	munmap(addr, UM_KERN_PAGE_SIZE);
+out_close:
+	close(fd);
+out:
+	return ok;
+}
+
+void init_new_thread_stack(void *sig_stack, void (*usr1_handler)(int))
+{
+	int flags = 0, pages;
+
+	if(sig_stack != NULL){
+		pages = (1 << UML_CONFIG_KERNEL_STACK_ORDER);
+		set_sigstack(sig_stack, pages * page_size());
+		flags = SA_ONSTACK;
+	}
+	if(usr1_handler){
+		struct sigaction sa;
+
+		sa.sa_handler = usr1_handler;
+		sigemptyset(&sa.sa_mask);
+		sa.sa_flags = flags;
+		sa.sa_restorer = NULL;
+		if(sigaction(SIGUSR1, &sa, NULL) < 0)
+			panic("init_new_thread_stack - sigaction failed - "
+			      "errno = %d\n", errno);
+	}
+}
+
+void init_new_thread_signals(void)
+{
+	set_handler(SIGSEGV, (__sighandler_t) sig_handler, SA_ONSTACK,
+		    SIGUSR1, SIGIO, SIGWINCH, SIGALRM, SIGVTALRM, -1);
+	set_handler(SIGTRAP, (__sighandler_t) sig_handler, SA_ONSTACK,
+		    SIGUSR1, SIGIO, SIGWINCH, SIGALRM, SIGVTALRM, -1);
+	set_handler(SIGFPE, (__sighandler_t) sig_handler, SA_ONSTACK,
+		    SIGUSR1, SIGIO, SIGWINCH, SIGALRM, SIGVTALRM, -1);
+	set_handler(SIGILL, (__sighandler_t) sig_handler, SA_ONSTACK,
+		    SIGUSR1, SIGIO, SIGWINCH, SIGALRM, SIGVTALRM, -1);
+	set_handler(SIGBUS, (__sighandler_t) sig_handler, SA_ONSTACK,
+		    SIGUSR1, SIGIO, SIGWINCH, SIGALRM, SIGVTALRM, -1);
+	set_handler(SIGUSR2, (__sighandler_t) sig_handler,
+		    SA_ONSTACK, SIGUSR1, SIGIO, SIGWINCH, SIGALRM, SIGVTALRM,
+		    -1);
+	signal(SIGHUP, SIG_IGN);
+
+	init_irq_signals(1);
+}
+
+int run_kernel_thread(int (*fn)(void *), void *arg, void **jmp_ptr)
+{
+	jmp_buf buf;
+	int n;
+
+	*jmp_ptr = &buf;
+	n = UML_SETJMP(&buf);
+	if(n != 0)
+		return n;
+	(*fn)(arg);
+	return 0;
+}

arch/um/os-Linux/sigio.c

@@ -0,0 +1,359 @@
+/*
+ * Copyright (C) 2002 Jeff Dike (jdike@karaya.com)
+ * Licensed under the GPL
+ */
+
+#include <unistd.h>
+#include <stdlib.h>
+#include <termios.h>
+#include <pty.h>
+#include <signal.h>
+#include <errno.h>
+#include <string.h>
+#include <sched.h>
+#include <sys/socket.h>
+#include <sys/poll.h>
+#include "init.h"
+#include "user.h"
+#include "kern_util.h"
+#include "user_util.h"
+#include "sigio.h"
+#include "os.h"
+#include "um_malloc.h"
+
+/* Protected by sigio_lock(), also used by sigio_cleanup, which is an
+ * exitcall.
+ */
+static int write_sigio_pid = -1;
+
+/* These arrays are initialized before the sigio thread is started, and
+ * the descriptors closed after it is killed.  So, it can't see them change.
+ * On the UML side, they are changed under the sigio_lock.
+ */
+#define SIGIO_FDS_INIT {-1, -1}
+
+static int write_sigio_fds[2] = SIGIO_FDS_INIT;
+static int sigio_private[2] = SIGIO_FDS_INIT;
+
+struct pollfds {
+	struct pollfd *poll;
+	int size;
+	int used;
+};
+
+/* Protected by sigio_lock().  Used by the sigio thread, but the UML thread
+ * synchronizes with it.
+ */
+static struct pollfds current_poll;
+static struct pollfds next_poll;
+static struct pollfds all_sigio_fds;
+
+static int write_sigio_thread(void *unused)
+{
+	struct pollfds *fds, tmp;
+	struct pollfd *p;
+	int i, n, respond_fd;
+	char c;
+
+        signal(SIGWINCH, SIG_IGN);
+	fds = &current_poll;
+	while(1){
+		n = poll(fds->poll, fds->used, -1);
+		if(n < 0){
+			if(errno == EINTR) continue;
+			printk("write_sigio_thread : poll returned %d, "
+			       "errno = %d\n", n, errno);
+		}
+		for(i = 0; i < fds->used; i++){
+			p = &fds->poll[i];
+			if(p->revents == 0) continue;
+			if(p->fd == sigio_private[1]){
+				n = os_read_file(sigio_private[1], &c, sizeof(c));
+				if(n != sizeof(c))
+					printk("write_sigio_thread : "
+					       "read on socket failed, "
+					       "err = %d\n", -n);
+				tmp = current_poll;
+				current_poll = next_poll;
+				next_poll = tmp;
+				respond_fd = sigio_private[1];
+			}
+			else {
+				respond_fd = write_sigio_fds[1];
+				fds->used--;
+				memmove(&fds->poll[i], &fds->poll[i + 1],
+					(fds->used - i) * sizeof(*fds->poll));
+			}
+
+			n = os_write_file(respond_fd, &c, sizeof(c));
+			if(n != sizeof(c))
+				printk("write_sigio_thread : write on socket "
+				       "failed, err = %d\n", -n);
+		}
+	}
+
+	return 0;
+}
+
+static int need_poll(struct pollfds *polls, int n)
+{
+	struct pollfd *new;
+
+	if(n <= polls->size)
+		return 0;
+
+	new = um_kmalloc_atomic(n * sizeof(struct pollfd));
+	if(new == NULL){
+		printk("need_poll : failed to allocate new pollfds\n");
+		return -ENOMEM;
+	}
+
+	memcpy(new, polls->poll, polls->used * sizeof(struct pollfd));
+	kfree(polls->poll);
+
+	polls->poll = new;
+	polls->size = n;
+	return 0;
+}
+
+/* Must be called with sigio_lock held, because it's needed by the marked
+ * critical section.
+ */
+static void update_thread(void)
+{
+	unsigned long flags;
+	int n;
+	char c;
+
+	flags = set_signals(0);
+	n = os_write_file(sigio_private[0], &c, sizeof(c));
+	if(n != sizeof(c)){
+		printk("update_thread : write failed, err = %d\n", -n);
+		goto fail;
+	}
+
+	n = os_read_file(sigio_private[0], &c, sizeof(c));
+	if(n != sizeof(c)){
+		printk("update_thread : read failed, err = %d\n", -n);
+		goto fail;
+	}
+
+	set_signals(flags);
+	return;
+ fail:
+	/* Critical section start */
+	if(write_sigio_pid != -1)
+		os_kill_process(write_sigio_pid, 1);
+	write_sigio_pid = -1;
+	close(sigio_private[0]);
+	close(sigio_private[1]);
+	close(write_sigio_fds[0]);
+	close(write_sigio_fds[1]);
+	/* Critical section end */
+	set_signals(flags);
+}
+
+int add_sigio_fd(int fd)
+{
+	struct pollfd *p;
+	int err = 0, i, n;
+
+	sigio_lock();
+	for(i = 0; i < all_sigio_fds.used; i++){
+		if(all_sigio_fds.poll[i].fd == fd)
+			break;
+	}
+	if(i == all_sigio_fds.used)
+		goto out;
+
+	p = &all_sigio_fds.poll[i];
+
+	for(i = 0; i < current_poll.used; i++){
+		if(current_poll.poll[i].fd == fd)
+			goto out;
+	}
+
+	n = current_poll.used;
+	err = need_poll(&next_poll, n + 1);
+	if(err)
+		goto out;
+
+	memcpy(next_poll.poll, current_poll.poll,
+	       current_poll.used * sizeof(struct pollfd));
+	next_poll.poll[n] = *p;
+	next_poll.used = n + 1;
+	update_thread();
+ out:
+	sigio_unlock();
+	return err;
+}
+
+int ignore_sigio_fd(int fd)
+{
+	struct pollfd *p;
+	int err = 0, i, n = 0;
+
+	/* This is called from exitcalls elsewhere in UML - if
+	 * sigio_cleanup has already run, then update_thread will hang
+	 * or fail because the thread is no longer running.
+	 */
+	if(write_sigio_pid == -1)
+		return -EIO;
+
+	sigio_lock();
+	for(i = 0; i < current_poll.used; i++){
+		if(current_poll.poll[i].fd == fd) break;
+	}
+	if(i == current_poll.used)
+		goto out;
+
+	err = need_poll(&next_poll, current_poll.used - 1);
+	if(err)
+		goto out;
+
+	for(i = 0; i < current_poll.used; i++){
+		p = &current_poll.poll[i];
+		if(p->fd != fd)
+			next_poll.poll[n++] = *p;
+	}
+	next_poll.used = current_poll.used - 1;
+
+	update_thread();
+ out:
+	sigio_unlock();
+	return err;
+}
+
+static struct pollfd *setup_initial_poll(int fd)
+{
+	struct pollfd *p;
+
+	p = um_kmalloc(sizeof(struct pollfd));
+	if (p == NULL) {
+		printk("setup_initial_poll : failed to allocate poll\n");
+		return NULL;
+	}
+	*p = ((struct pollfd) { .fd		= fd,
+				.events 	= POLLIN,
+				.revents 	= 0 });
+	return p;
+}
+
+static void write_sigio_workaround(void)
+{
+	unsigned long stack;
+	struct pollfd *p;
+	int err;
+	int l_write_sigio_fds[2];
+	int l_sigio_private[2];
+	int l_write_sigio_pid;
+
+	/* We call this *tons* of times - and most ones we must just fail. */
+	sigio_lock();
+	l_write_sigio_pid = write_sigio_pid;
+	sigio_unlock();
+
+	if (l_write_sigio_pid != -1)
+		return;
+
+	err = os_pipe(l_write_sigio_fds, 1, 1);
+	if(err < 0){
+		printk("write_sigio_workaround - os_pipe 1 failed, "
+		       "err = %d\n", -err);
+		return;
+	}
+	err = os_pipe(l_sigio_private, 1, 1);
+	if(err < 0){
+		printk("write_sigio_workaround - os_pipe 2 failed, "
+		       "err = %d\n", -err);
+		goto out_close1;
+	}
+
+	p = setup_initial_poll(l_sigio_private[1]);
+	if(!p)
+		goto out_close2;
+
+	sigio_lock();
+
+	/* Did we race? Don't try to optimize this, please, it's not so likely
+	 * to happen, and no more than once at the boot. */
+	if(write_sigio_pid != -1)
+		goto out_free;
+
+	current_poll = ((struct pollfds) { .poll 	= p,
+					   .used 	= 1,
+					   .size 	= 1 });
+
+	if (write_sigio_irq(l_write_sigio_fds[0]))
+		goto out_clear_poll;
+
+	memcpy(write_sigio_fds, l_write_sigio_fds, sizeof(l_write_sigio_fds));
+	memcpy(sigio_private, l_sigio_private, sizeof(l_sigio_private));
+
+	write_sigio_pid = run_helper_thread(write_sigio_thread, NULL,
+					    CLONE_FILES | CLONE_VM, &stack, 0);
+
+	if (write_sigio_pid < 0)
+		goto out_clear;
+
+	sigio_unlock();
+	return;
+
+out_clear:
+	write_sigio_pid = -1;
+	write_sigio_fds[0] = -1;
+	write_sigio_fds[1] = -1;
+	sigio_private[0] = -1;
+	sigio_private[1] = -1;
+out_clear_poll:
+	current_poll = ((struct pollfds) { .poll	= NULL,
+					   .size	= 0,
+					   .used	= 0 });
+out_free:
+	sigio_unlock();
+	kfree(p);
+out_close2:
+	close(l_sigio_private[0]);
+	close(l_sigio_private[1]);
+out_close1:
+	close(l_write_sigio_fds[0]);
+	close(l_write_sigio_fds[1]);
+}
+
+void maybe_sigio_broken(int fd, int read)
+{
+	int err;
+
+	if(!isatty(fd))
+		return;
+
+	if((read || pty_output_sigio) && (!read || pty_close_sigio))
+		return;
+
+	write_sigio_workaround();
+
+	sigio_lock();
+	err = need_poll(&all_sigio_fds, all_sigio_fds.used + 1);
+	if(err){
+		printk("maybe_sigio_broken - failed to add pollfd for "
+		       "descriptor %d\n", fd);
+		goto out;
+	}
+
+	all_sigio_fds.poll[all_sigio_fds.used++] =
+		((struct pollfd) { .fd  	= fd,
+				   .events 	= read ? POLLIN : POLLOUT,
+				   .revents 	= 0 });
+out:
+	sigio_unlock();
+}
+
+static void sigio_cleanup(void)
+{
+	if(write_sigio_pid != -1){
+		os_kill_process(write_sigio_pid, 1);
+		write_sigio_pid = -1;
+	}
+}
+
+__uml_exitcall(sigio_cleanup);

arch/um/os-Linux/signal.c

@@ -0,0 +1,245 @@
+/*
+ * Copyright (C) 2004 PathScale, Inc
+ * Licensed under the GPL
+ */
+
+#include <signal.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <stdarg.h>
+#include <string.h>
+#include <sys/mman.h>
+#include "user_util.h"
+#include "user.h"
+#include "signal_kern.h"
+#include "sysdep/sigcontext.h"
+#include "sysdep/barrier.h"
+#include "sigcontext.h"
+#include "mode.h"
+#include "os.h"
+
+/* These are the asynchronous signals.  SIGVTALRM and SIGARLM are handled
+ * together under SIGVTALRM_BIT.  SIGPROF is excluded because we want to
+ * be able to profile all of UML, not just the non-critical sections.  If
+ * profiling is not thread-safe, then that is not my problem.  We can disable
+ * profiling when SMP is enabled in that case.
+ */
+#define SIGIO_BIT 0
+#define SIGIO_MASK (1 << SIGIO_BIT)
+
+#define SIGVTALRM_BIT 1
+#define SIGVTALRM_MASK (1 << SIGVTALRM_BIT)
+
+#define SIGALRM_BIT 2
+#define SIGALRM_MASK (1 << SIGALRM_BIT)
+
+/* These are used by both the signal handlers and
+ * block/unblock_signals.  I don't want modifications cached in a
+ * register - they must go straight to memory.
+ */
+static volatile int signals_enabled = 1;
+static volatile int pending = 0;
+
+void sig_handler(int sig, struct sigcontext *sc)
+{
+	int enabled;
+
+	enabled = signals_enabled;
+	if(!enabled && (sig == SIGIO)){
+		pending |= SIGIO_MASK;
+		return;
+	}
+
+	block_signals();
+
+	CHOOSE_MODE_PROC(sig_handler_common_tt, sig_handler_common_skas,
+			 sig, sc);
+
+	set_signals(enabled);
+}
+
+static void real_alarm_handler(int sig, struct sigcontext *sc)
+{
+	if(sig == SIGALRM)
+		switch_timers(0);
+
+	CHOOSE_MODE_PROC(sig_handler_common_tt, sig_handler_common_skas,
+			 sig, sc);
+
+	if(sig == SIGALRM)
+		switch_timers(1);
+
+}
+
+void alarm_handler(int sig, struct sigcontext *sc)
+{
+	int enabled;
+
+	enabled = signals_enabled;
+	if(!signals_enabled){
+		if(sig == SIGVTALRM)
+			pending |= SIGVTALRM_MASK;
+		else pending |= SIGALRM_MASK;
+
+		return;
+	}
+
+	block_signals();
+
+	real_alarm_handler(sig, sc);
+	set_signals(enabled);
+}
+
+void set_sigstack(void *sig_stack, int size)
+{
+	stack_t stack = ((stack_t) { .ss_flags	= 0,
+				     .ss_sp	= (__ptr_t) sig_stack,
+				     .ss_size 	= size - sizeof(void *) });
+
+	if(sigaltstack(&stack, NULL) != 0)
+		panic("enabling signal stack failed, errno = %d\n", errno);
+}
+
+void remove_sigstack(void)
+{
+	stack_t stack = ((stack_t) { .ss_flags	= SS_DISABLE,
+				     .ss_sp	= NULL,
+				     .ss_size	= 0 });
+
+	if(sigaltstack(&stack, NULL) != 0)
+		panic("disabling signal stack failed, errno = %d\n", errno);
+}
+
+void (*handlers[_NSIG])(int sig, struct sigcontext *sc);
+
+extern void hard_handler(int sig);
+
+void set_handler(int sig, void (*handler)(int), int flags, ...)
+{
+	struct sigaction action;
+	va_list ap;
+	sigset_t sig_mask;
+	int mask;
+
+	handlers[sig] = (void (*)(int, struct sigcontext *)) handler;
+	action.sa_handler = hard_handler;
+
+	sigemptyset(&action.sa_mask);
+
+	va_start(ap, flags);
+	while((mask = va_arg(ap, int)) != -1)
+		sigaddset(&action.sa_mask, mask);
+	va_end(ap);
+
+	action.sa_flags = flags;
+	action.sa_restorer = NULL;
+	if(sigaction(sig, &action, NULL) < 0)
+		panic("sigaction failed - errno = %d\n", errno);
+
+	sigemptyset(&sig_mask);
+	sigaddset(&sig_mask, sig);
+	if(sigprocmask(SIG_UNBLOCK, &sig_mask, NULL) < 0)
+		panic("sigprocmask failed - errno = %d\n", errno);
+}
+
+int change_sig(int signal, int on)
+{
+	sigset_t sigset, old;
+
+	sigemptyset(&sigset);
+	sigaddset(&sigset, signal);
+	sigprocmask(on ? SIG_UNBLOCK : SIG_BLOCK, &sigset, &old);
+	return(!sigismember(&old, signal));
+}
+
+void block_signals(void)
+{
+	signals_enabled = 0;
+	/* This must return with signals disabled, so this barrier
+	 * ensures that writes are flushed out before the return.
+	 * This might matter if gcc figures out how to inline this and
+	 * decides to shuffle this code into the caller.
+	 */
+	mb();
+}
+
+void unblock_signals(void)
+{
+	int save_pending;
+
+	if(signals_enabled == 1)
+		return;
+
+	/* We loop because the IRQ handler returns with interrupts off.  So,
+	 * interrupts may have arrived and we need to re-enable them and
+	 * recheck pending.
+	 */
+	while(1){
+		/* Save and reset save_pending after enabling signals.  This
+		 * way, pending won't be changed while we're reading it.
+		 */
+		signals_enabled = 1;
+
+		/* Setting signals_enabled and reading pending must
+		 * happen in this order.
+		 */
+		mb();
+
+		save_pending = pending;
+		if(save_pending == 0){
+			/* This must return with signals enabled, so
+			 * this barrier ensures that writes are
+			 * flushed out before the return.  This might
+			 * matter if gcc figures out how to inline
+			 * this (unlikely, given its size) and decides
+			 * to shuffle this code into the caller.
+			 */
+			mb();
+			return;
+		}
+
+		pending = 0;
+
+		/* We have pending interrupts, so disable signals, as the
+		 * handlers expect them off when they are called.  They will
+		 * be enabled again above.
+		 */
+
+		signals_enabled = 0;
+
+		/* Deal with SIGIO first because the alarm handler might
+		 * schedule, leaving the pending SIGIO stranded until we come
+		 * back here.
+		 */
+		if(save_pending & SIGIO_MASK)
+			CHOOSE_MODE_PROC(sig_handler_common_tt,
+					 sig_handler_common_skas, SIGIO, NULL);
+
+		if(save_pending & SIGALRM_MASK)
+			real_alarm_handler(SIGALRM, NULL);
+
+		if(save_pending & SIGVTALRM_MASK)
+			real_alarm_handler(SIGVTALRM, NULL);
+	}
+}
+
+int get_signals(void)
+{
+	return signals_enabled;
+}
+
+int set_signals(int enable)
+{
+	int ret;
+	if(signals_enabled == enable)
+		return enable;
+
+	ret = signals_enabled;
+	if(enable)
+		unblock_signals();
+	else block_signals();
+
+	return ret;
+}

arch/um/os-Linux/skas/Makefile

@@ -0,0 +1,10 @@
+#
+# Copyright (C) 2002 - 2004 Jeff Dike (jdike@addtoit.com)
+# Licensed under the GPL
+#
+
+obj-y := mem.o process.o trap.o
+
+USER_OBJS := mem.o process.o trap.o
+
+include arch/um/scripts/Makefile.rules

arch/um/os-Linux/skas/mem.c

@@ -0,0 +1,287 @@
+/*
+ * Copyright (C) 2002 Jeff Dike (jdike@karaya.com)
+ * Licensed under the GPL
+ */
+
+#include <signal.h>
+#include <errno.h>
+#include <string.h>
+#include <sys/mman.h>
+#include <sys/wait.h>
+#include <asm/page.h>
+#include <asm/unistd.h>
+#include "mem_user.h"
+#include "mem.h"
+#include "skas.h"
+#include "user.h"
+#include "os.h"
+#include "proc_mm.h"
+#include "ptrace_user.h"
+#include "user_util.h"
+#include "kern_util.h"
+#include "task.h"
+#include "registers.h"
+#include "uml-config.h"
+#include "sysdep/ptrace.h"
+#include "sysdep/stub.h"
+
+extern unsigned long batch_syscall_stub, __syscall_stub_start;
+
+extern void wait_stub_done(int pid, int sig, char * fname);
+
+static inline unsigned long *check_init_stack(struct mm_id * mm_idp,
+					      unsigned long *stack)
+{
+	if(stack == NULL) {
+		stack = (unsigned long *) mm_idp->stack + 2;
+		*stack = 0;
+	}
+	return stack;
+}
+
+extern int proc_mm;
+
+int single_count = 0;
+int multi_count = 0;
+int multi_op_count = 0;
+
+static inline long do_syscall_stub(struct mm_id * mm_idp, void **addr)
+{
+	unsigned long regs[MAX_REG_NR];
+	int n, i;
+	long ret, offset;
+	unsigned long * data;
+	unsigned long * syscall;
+	int pid = mm_idp->u.pid;
+
+	if(proc_mm)
+#warning Need to look up userspace_pid by cpu
+		pid = userspace_pid[0];
+
+	multi_count++;
+
+	get_safe_registers(regs, NULL);
+	regs[REGS_IP_INDEX] = UML_CONFIG_STUB_CODE +
+		((unsigned long) &batch_syscall_stub -
+		 (unsigned long) &__syscall_stub_start);
+
+	n = ptrace_setregs(pid, regs);
+	if(n < 0){
+		printk("Registers - \n");
+		for(i = 0; i < MAX_REG_NR; i++)
+			printk("\t%d\t0x%lx\n", i, regs[i]);
+		panic("do_syscall_stub : PTRACE_SETREGS failed, errno = %d\n",
+		      -n);
+	}
+
+	wait_stub_done(pid, 0, "do_syscall_stub");
+
+	/* When the stub stops, we find the following values on the
+	 * beginning of the stack:
+	 * (long )return_value
+	 * (long )offset to failed sycall-data (0, if no error)
+	 */
+	ret = *((unsigned long *) mm_idp->stack);
+	offset = *((unsigned long *) mm_idp->stack + 1);
+	if (offset) {
+		data = (unsigned long *)(mm_idp->stack +
+					 offset - UML_CONFIG_STUB_DATA);
+		printk("do_syscall_stub : ret = %ld, offset = %ld, "
+		       "data = %p\n", ret, offset, data);
+		syscall = (unsigned long *)((unsigned long)data + data[0]);
+		printk("do_syscall_stub: syscall %ld failed, return value = "
+		       "0x%lx, expected return value = 0x%lx\n",
+		       syscall[0], ret, syscall[7]);
+		printk("    syscall parameters: "
+		       "0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx\n",
+		       syscall[1], syscall[2], syscall[3],
+		       syscall[4], syscall[5], syscall[6]);
+		for(n = 1; n < data[0]/sizeof(long); n++) {
+			if(n == 1)
+				printk("    additional syscall data:");
+			if(n % 4 == 1)
+				printk("\n      ");
+			printk("  0x%lx", data[n]);
+		}
+		if(n > 1)
+			printk("\n");
+	}
+	else ret = 0;
+
+	*addr = check_init_stack(mm_idp, NULL);
+
+	return ret;
+}
+
+long run_syscall_stub(struct mm_id * mm_idp, int syscall,
+		      unsigned long *args, long expected, void **addr,
+		      int done)
+{
+	unsigned long *stack = check_init_stack(mm_idp, *addr);
+
+	if(done && *addr == NULL)
+		single_count++;
+
+	*stack += sizeof(long);
+	stack += *stack / sizeof(long);
+
+	*stack++ = syscall;
+	*stack++ = args[0];
+	*stack++ = args[1];
+	*stack++ = args[2];
+	*stack++ = args[3];
+	*stack++ = args[4];
+	*stack++ = args[5];
+	*stack++ = expected;
+	*stack = 0;
+	multi_op_count++;
+
+	if(!done && ((((unsigned long) stack) & ~PAGE_MASK) <
+		     PAGE_SIZE - 10 * sizeof(long))){
+		*addr = stack;
+		return 0;
+	}
+
+	return do_syscall_stub(mm_idp, addr);
+}
+
+long syscall_stub_data(struct mm_id * mm_idp,
+		       unsigned long *data, int data_count,
+		       void **addr, void **stub_addr)
+{
+	unsigned long *stack;
+	int ret = 0;
+
+	/* If *addr still is uninitialized, it *must* contain NULL.
+	 * Thus in this case do_syscall_stub correctly won't be called.
+	 */
+	if((((unsigned long) *addr) & ~PAGE_MASK) >=
+	   PAGE_SIZE - (10 + data_count) * sizeof(long)) {
+		ret = do_syscall_stub(mm_idp, addr);
+		/* in case of error, don't overwrite data on stack */
+		if(ret)
+			return ret;
+	}
+
+	stack = check_init_stack(mm_idp, *addr);
+	*addr = stack;
+
+	*stack = data_count * sizeof(long);
+
+	memcpy(stack + 1, data, data_count * sizeof(long));
+
+	*stub_addr = (void *)(((unsigned long)(stack + 1) & ~PAGE_MASK) +
+			      UML_CONFIG_STUB_DATA);
+
+	return 0;
+}
+
+int map(struct mm_id * mm_idp, unsigned long virt, unsigned long len,
+	int r, int w, int x, int phys_fd, unsigned long long offset,
+	int done, void **data)
+{
+	int prot, ret;
+
+	prot = (r ? PROT_READ : 0) | (w ? PROT_WRITE : 0) |
+		(x ? PROT_EXEC : 0);
+
+	if(proc_mm){
+		struct proc_mm_op map;
+		int fd = mm_idp->u.mm_fd;
+
+		map = ((struct proc_mm_op) { .op	= MM_MMAP,
+				       .u		=
+				       { .mmap	=
+					 { .addr	= virt,
+					   .len	= len,
+					   .prot	= prot,
+					   .flags	= MAP_SHARED |
+					   MAP_FIXED,
+					   .fd	= phys_fd,
+					   .offset= offset
+					 } } } );
+		ret = os_write_file(fd, &map, sizeof(map));
+		if(ret != sizeof(map))
+			printk("map : /proc/mm map failed, err = %d\n", -ret);
+		else ret = 0;
+	}
+	else {
+		unsigned long args[] = { virt, len, prot,
+					 MAP_SHARED | MAP_FIXED, phys_fd,
+					 MMAP_OFFSET(offset) };
+
+		ret = run_syscall_stub(mm_idp, STUB_MMAP_NR, args, virt,
+				       data, done);
+	}
+
+	return ret;
+}
+
+int unmap(struct mm_id * mm_idp, void *addr, unsigned long len, int done,
+	  void **data)
+{
+	int ret;
+
+	if(proc_mm){
+		struct proc_mm_op unmap;
+		int fd = mm_idp->u.mm_fd;
+
+		unmap = ((struct proc_mm_op) { .op	= MM_MUNMAP,
+					 .u	=
+					 { .munmap	=
+					   { .addr	=
+					     (unsigned long) addr,
+					     .len		= len } } } );
+		ret = os_write_file(fd, &unmap, sizeof(unmap));
+		if(ret != sizeof(unmap))
+			printk("unmap - proc_mm write returned %d\n", ret);
+		else ret = 0;
+	}
+	else {
+		unsigned long args[] = { (unsigned long) addr, len, 0, 0, 0,
+					 0 };
+
+		ret = run_syscall_stub(mm_idp, __NR_munmap, args, 0,
+				       data, done);
+	}
+
+	return ret;
+}
+
+int protect(struct mm_id * mm_idp, unsigned long addr, unsigned long len,
+	    int r, int w, int x, int done, void **data)
+{
+	struct proc_mm_op protect;
+	int prot, ret;
+
+	prot = (r ? PROT_READ : 0) | (w ? PROT_WRITE : 0) |
+		(x ? PROT_EXEC : 0);
+	if(proc_mm){
+		int fd = mm_idp->u.mm_fd;
+
+		protect = ((struct proc_mm_op) { .op	= MM_MPROTECT,
+					   .u	=
+					   { .mprotect	=
+					     { .addr	=
+					       (unsigned long) addr,
+					       .len	= len,
+					       .prot	= prot } } } );
+
+		ret = os_write_file(fd, &protect, sizeof(protect));
+		if(ret != sizeof(protect))
+			printk("protect failed, err = %d", -ret);
+		else ret = 0;
+	}
+	else {
+		unsigned long args[] = { addr, len, prot, 0, 0, 0 };
+
+		ret = run_syscall_stub(mm_idp, __NR_mprotect, args, 0,
+				       data, done);
+	}
+
+	return ret;
+}
+
+void before_mem_skas(unsigned long unused)
+{
+}

arch/um/os-Linux/skas/process.c

@@ -0,0 +1,550 @@
+/*
+ * Copyright (C) 2002- 2004 Jeff Dike (jdike@addtoit.com)
+ * Licensed under the GPL
+ */
+
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <errno.h>
+#include <signal.h>
+#include <sched.h>
+#include "ptrace_user.h"
+#include <sys/wait.h>
+#include <sys/mman.h>
+#include <sys/user.h>
+#include <sys/time.h>
+#include <sys/syscall.h>
+#include <asm/types.h>
+#include "user.h"
+#include "sysdep/ptrace.h"
+#include "user_util.h"
+#include "kern_util.h"
+#include "skas.h"
+#include "stub-data.h"
+#include "mm_id.h"
+#include "sysdep/sigcontext.h"
+#include "sysdep/stub.h"
+#include "os.h"
+#include "proc_mm.h"
+#include "skas_ptrace.h"
+#include "chan_user.h"
+#include "registers.h"
+#include "mem.h"
+#include "uml-config.h"
+#include "process.h"
+#include "longjmp.h"
+
+int is_skas_winch(int pid, int fd, void *data)
+{
+	if(pid != os_getpgrp())
+		return(0);
+
+	register_winch_irq(-1, fd, -1, data);
+	return(1);
+}
+
+void wait_stub_done(int pid, int sig, char * fname)
+{
+	int n, status, err;
+
+	do {
+		if ( sig != -1 ) {
+			err = ptrace(PTRACE_CONT, pid, 0, sig);
+			if(err)
+				panic("%s : continue failed, errno = %d\n",
+				      fname, errno);
+		}
+		sig = 0;
+
+		CATCH_EINTR(n = waitpid(pid, &status, WUNTRACED));
+	} while((n >= 0) && WIFSTOPPED(status) &&
+	        ((WSTOPSIG(status) == SIGVTALRM) ||
+		 /* running UML inside a detached screen can cause
+		  * SIGWINCHes
+		  */
+		 (WSTOPSIG(status) == SIGWINCH)));
+
+	if((n < 0) || !WIFSTOPPED(status) ||
+	   (WSTOPSIG(status) != SIGUSR1 && WSTOPSIG(status) != SIGTRAP)){
+		unsigned long regs[MAX_REG_NR];
+
+		if(ptrace(PTRACE_GETREGS, pid, 0, regs) < 0)
+			printk("Failed to get registers from stub, "
+			       "errno = %d\n", errno);
+		else {
+			int i;
+
+			printk("Stub registers -\n");
+			for(i = 0; i < ARRAY_SIZE(regs); i++)
+				printk("\t%d - %lx\n", i, regs[i]);
+		}
+		panic("%s : failed to wait for SIGUSR1/SIGTRAP, "
+		      "pid = %d, n = %d, errno = %d, status = 0x%x\n",
+		      fname, pid, n, errno, status);
+	}
+}
+
+extern unsigned long current_stub_stack(void);
+
+void get_skas_faultinfo(int pid, struct faultinfo * fi)
+{
+	int err;
+
+	if(ptrace_faultinfo){
+		err = ptrace(PTRACE_FAULTINFO, pid, 0, fi);
+		if(err)
+			panic("get_skas_faultinfo - PTRACE_FAULTINFO failed, "
+			      "errno = %d\n", errno);
+
+		/* Special handling for i386, which has different structs */
+		if (sizeof(struct ptrace_faultinfo) < sizeof(struct faultinfo))
+			memset((char *)fi + sizeof(struct ptrace_faultinfo), 0,
+			       sizeof(struct faultinfo) -
+			       sizeof(struct ptrace_faultinfo));
+	}
+	else {
+		wait_stub_done(pid, SIGSEGV, "get_skas_faultinfo");
+
+		/* faultinfo is prepared by the stub-segv-handler at start of
+		 * the stub stack page. We just have to copy it.
+		 */
+		memcpy(fi, (void *)current_stub_stack(), sizeof(*fi));
+	}
+}
+
+static void handle_segv(int pid, union uml_pt_regs * regs)
+{
+	get_skas_faultinfo(pid, &regs->skas.faultinfo);
+	segv(regs->skas.faultinfo, 0, 1, NULL);
+}
+
+/*To use the same value of using_sysemu as the caller, ask it that value (in local_using_sysemu)*/
+static void handle_trap(int pid, union uml_pt_regs *regs, int local_using_sysemu)
+{
+	int err, status;
+
+	/* Mark this as a syscall */
+	UPT_SYSCALL_NR(regs) = PT_SYSCALL_NR(regs->skas.regs);
+
+	if (!local_using_sysemu)
+	{
+		err = ptrace(PTRACE_POKEUSR, pid, PT_SYSCALL_NR_OFFSET,
+			     __NR_getpid);
+		if(err < 0)
+			panic("handle_trap - nullifying syscall failed errno = %d\n",
+			      errno);
+
+		err = ptrace(PTRACE_SYSCALL, pid, 0, 0);
+		if(err < 0)
+			panic("handle_trap - continuing to end of syscall failed, "
+			      "errno = %d\n", errno);
+
+		CATCH_EINTR(err = waitpid(pid, &status, WUNTRACED));
+		if((err < 0) || !WIFSTOPPED(status) ||
+		   (WSTOPSIG(status) != SIGTRAP + 0x80))
+			panic("handle_trap - failed to wait at end of syscall, "
+			      "errno = %d, status = %d\n", errno, status);
+	}
+
+	handle_syscall(regs);
+}
+
+extern int __syscall_stub_start;
+
+static int userspace_tramp(void *stack)
+{
+	void *addr;
+	int err;
+
+	ptrace(PTRACE_TRACEME, 0, 0, 0);
+
+	init_new_thread_signals();
+	err = set_interval(1);
+	if(err)
+		panic("userspace_tramp - setting timer failed, errno = %d\n",
+		      err);
+
+	if(!proc_mm){
+		/* This has a pte, but it can't be mapped in with the usual
+		 * tlb_flush mechanism because this is part of that mechanism
+		 */
+		int fd;
+		__u64 offset;
+		fd = phys_mapping(to_phys(&__syscall_stub_start), &offset);
+		addr = mmap64((void *) UML_CONFIG_STUB_CODE, page_size(),
+			      PROT_EXEC, MAP_FIXED | MAP_PRIVATE, fd, offset);
+		if(addr == MAP_FAILED){
+			printk("mapping mmap stub failed, errno = %d\n",
+			       errno);
+			exit(1);
+		}
+
+		if(stack != NULL){
+			fd = phys_mapping(to_phys(stack), &offset);
+			addr = mmap((void *) UML_CONFIG_STUB_DATA, page_size(),
+				    PROT_READ | PROT_WRITE,
+				    MAP_FIXED | MAP_SHARED, fd, offset);
+			if(addr == MAP_FAILED){
+				printk("mapping segfault stack failed, "
+				       "errno = %d\n", errno);
+				exit(1);
+			}
+		}
+	}
+	if(!ptrace_faultinfo && (stack != NULL)){
+		struct sigaction sa;
+
+		unsigned long v = UML_CONFIG_STUB_CODE +
+				  (unsigned long) stub_segv_handler -
+				  (unsigned long) &__syscall_stub_start;
+
+		set_sigstack((void *) UML_CONFIG_STUB_DATA, page_size());
+		sigemptyset(&sa.sa_mask);
+		sigaddset(&sa.sa_mask, SIGIO);
+		sigaddset(&sa.sa_mask, SIGWINCH);
+		sigaddset(&sa.sa_mask, SIGALRM);
+		sigaddset(&sa.sa_mask, SIGVTALRM);
+		sigaddset(&sa.sa_mask, SIGUSR1);
+		sa.sa_flags = SA_ONSTACK;
+		sa.sa_handler = (void *) v;
+		sa.sa_restorer = NULL;
+		if(sigaction(SIGSEGV, &sa, NULL) < 0)
+			panic("userspace_tramp - setting SIGSEGV handler "
+			      "failed - errno = %d\n", errno);
+	}
+
+	os_stop_process(os_getpid());
+	return(0);
+}
+
+/* Each element set once, and only accessed by a single processor anyway */
+#undef NR_CPUS
+#define NR_CPUS 1
+int userspace_pid[NR_CPUS];
+
+int start_userspace(unsigned long stub_stack)
+{
+	void *stack;
+	unsigned long sp;
+	int pid, status, n, flags;
+
+	stack = mmap(NULL, PAGE_SIZE, PROT_READ | PROT_WRITE | PROT_EXEC,
+		     MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+	if(stack == MAP_FAILED)
+		panic("start_userspace : mmap failed, errno = %d", errno);
+	sp = (unsigned long) stack + PAGE_SIZE - sizeof(void *);
+
+	flags = CLONE_FILES | SIGCHLD;
+	if(proc_mm) flags |= CLONE_VM;
+	pid = clone(userspace_tramp, (void *) sp, flags, (void *) stub_stack);
+	if(pid < 0)
+		panic("start_userspace : clone failed, errno = %d", errno);
+
+	do {
+		CATCH_EINTR(n = waitpid(pid, &status, WUNTRACED));
+		if(n < 0)
+			panic("start_userspace : wait failed, errno = %d",
+			      errno);
+	} while(WIFSTOPPED(status) && (WSTOPSIG(status) == SIGVTALRM));
+
+	if(!WIFSTOPPED(status) || (WSTOPSIG(status) != SIGSTOP))
+		panic("start_userspace : expected SIGSTOP, got status = %d",
+		      status);
+
+	if (ptrace(PTRACE_OLDSETOPTIONS, pid, NULL, (void *)PTRACE_O_TRACESYSGOOD) < 0)
+		panic("start_userspace : PTRACE_OLDSETOPTIONS failed, errno=%d\n",
+		      errno);
+
+	if(munmap(stack, PAGE_SIZE) < 0)
+		panic("start_userspace : munmap failed, errno = %d\n", errno);
+
+	return(pid);
+}
+
+void userspace(union uml_pt_regs *regs)
+{
+	int err, status, op, pid = userspace_pid[0];
+	int local_using_sysemu; /*To prevent races if using_sysemu changes under us.*/
+
+	while(1){
+		restore_registers(pid, regs);
+
+		/* Now we set local_using_sysemu to be used for one loop */
+		local_using_sysemu = get_using_sysemu();
+
+		op = SELECT_PTRACE_OPERATION(local_using_sysemu, singlestepping(NULL));
+
+		err = ptrace(op, pid, 0, 0);
+		if(err)
+			panic("userspace - could not resume userspace process, "
+			      "pid=%d, ptrace operation = %d, errno = %d\n",
+			      pid, op, errno);
+
+		CATCH_EINTR(err = waitpid(pid, &status, WUNTRACED));
+		if(err < 0)
+			panic("userspace - waitpid failed, errno = %d\n",
+			      errno);
+
+		regs->skas.is_user = 1;
+		save_registers(pid, regs);
+		UPT_SYSCALL_NR(regs) = -1; /* Assume: It's not a syscall */
+
+		if(WIFSTOPPED(status)){
+		  	switch(WSTOPSIG(status)){
+			case SIGSEGV:
+				if(PTRACE_FULL_FAULTINFO || !ptrace_faultinfo)
+					user_signal(SIGSEGV, regs, pid);
+				else handle_segv(pid, regs);
+				break;
+			case SIGTRAP + 0x80:
+			        handle_trap(pid, regs, local_using_sysemu);
+				break;
+			case SIGTRAP:
+				relay_signal(SIGTRAP, regs);
+				break;
+			case SIGIO:
+			case SIGVTALRM:
+			case SIGILL:
+			case SIGBUS:
+			case SIGFPE:
+			case SIGWINCH:
+				user_signal(WSTOPSIG(status), regs, pid);
+				break;
+			default:
+			        printk("userspace - child stopped with signal "
+				       "%d\n", WSTOPSIG(status));
+			}
+			pid = userspace_pid[0];
+			interrupt_end();
+
+			/* Avoid -ERESTARTSYS handling in host */
+			if(PT_SYSCALL_NR_OFFSET != PT_SYSCALL_RET_OFFSET)
+				PT_SYSCALL_NR(regs->skas.regs) = -1;
+		}
+	}
+}
+
+int copy_context_skas0(unsigned long new_stack, int pid)
+{
+	int err;
+	unsigned long regs[MAX_REG_NR];
+	unsigned long fp_regs[HOST_FP_SIZE];
+	unsigned long current_stack = current_stub_stack();
+	struct stub_data *data = (struct stub_data *) current_stack;
+	struct stub_data *child_data = (struct stub_data *) new_stack;
+	__u64 new_offset;
+	int new_fd = phys_mapping(to_phys((void *)new_stack), &new_offset);
+
+	/* prepare offset and fd of child's stack as argument for parent's
+	 * and child's mmap2 calls
+	 */
+	*data = ((struct stub_data) { .offset	= MMAP_OFFSET(new_offset),
+				      .fd	= new_fd,
+				      .timer    = ((struct itimerval)
+					            { { 0, 1000000 / hz() },
+						      { 0, 1000000 / hz() }})});
+	get_safe_registers(regs, fp_regs);
+
+	/* Set parent's instruction pointer to start of clone-stub */
+	regs[REGS_IP_INDEX] = UML_CONFIG_STUB_CODE +
+				(unsigned long) stub_clone_handler -
+				(unsigned long) &__syscall_stub_start;
+	regs[REGS_SP_INDEX] = UML_CONFIG_STUB_DATA + PAGE_SIZE -
+		sizeof(void *);
+#ifdef __SIGNAL_FRAMESIZE
+	regs[REGS_SP_INDEX] -= __SIGNAL_FRAMESIZE;
+#endif
+	err = ptrace_setregs(pid, regs);
+	if(err < 0)
+		panic("copy_context_skas0 : PTRACE_SETREGS failed, "
+		      "pid = %d, errno = %d\n", pid, -err);
+
+	err = ptrace_setfpregs(pid, fp_regs);
+	if(err < 0)
+		panic("copy_context_skas0 : PTRACE_SETFPREGS failed, "
+		      "pid = %d, errno = %d\n", pid, -err);
+
+	/* set a well known return code for detection of child write failure */
+	child_data->err = 12345678;
+
+	/* Wait, until parent has finished its work: read child's pid from
+	 * parent's stack, and check, if bad result.
+	 */
+	wait_stub_done(pid, 0, "copy_context_skas0");
+
+	pid = data->err;
+	if(pid < 0)
+		panic("copy_context_skas0 - stub-parent reports error %d\n",
+		      -pid);
+
+	/* Wait, until child has finished too: read child's result from
+	 * child's stack and check it.
+	 */
+	wait_stub_done(pid, -1, "copy_context_skas0");
+	if (child_data->err != UML_CONFIG_STUB_DATA)
+		panic("copy_context_skas0 - stub-child reports error %ld\n",
+		      child_data->err);
+
+	if (ptrace(PTRACE_OLDSETOPTIONS, pid, NULL,
+		   (void *)PTRACE_O_TRACESYSGOOD) < 0)
+		panic("copy_context_skas0 : PTRACE_OLDSETOPTIONS failed, "
+		      "errno = %d\n", errno);
+
+	return pid;
+}
+
+/*
+ * This is used only, if stub pages are needed, while proc_mm is
+ * availabl. Opening /proc/mm creates a new mm_context, which lacks
+ * the stub-pages. Thus, we map them using /proc/mm-fd
+ */
+void map_stub_pages(int fd, unsigned long code,
+		    unsigned long data, unsigned long stack)
+{
+	struct proc_mm_op mmop;
+	int n;
+	__u64 code_offset;
+	int code_fd = phys_mapping(to_phys((void *) &__syscall_stub_start),
+				   &code_offset);
+
+	mmop = ((struct proc_mm_op) { .op        = MM_MMAP,
+				      .u         =
+				      { .mmap    =
+					{ .addr    = code,
+					  .len     = PAGE_SIZE,
+					  .prot    = PROT_EXEC,
+					  .flags   = MAP_FIXED | MAP_PRIVATE,
+					  .fd      = code_fd,
+					  .offset  = code_offset
+	} } });
+	n = os_write_file(fd, &mmop, sizeof(mmop));
+	if(n != sizeof(mmop)){
+		printk("mmap args - addr = 0x%lx, fd = %d, offset = %llx\n",
+		       code, code_fd, (unsigned long long) code_offset);
+		panic("map_stub_pages : /proc/mm map for code failed, "
+		      "err = %d\n", -n);
+	}
+
+	if ( stack ) {
+		__u64 map_offset;
+		int map_fd = phys_mapping(to_phys((void *)stack), &map_offset);
+		mmop = ((struct proc_mm_op)
+				{ .op        = MM_MMAP,
+				  .u         =
+				  { .mmap    =
+				    { .addr    = data,
+				      .len     = PAGE_SIZE,
+				      .prot    = PROT_READ | PROT_WRITE,
+				      .flags   = MAP_FIXED | MAP_SHARED,
+				      .fd      = map_fd,
+				      .offset  = map_offset
+		} } });
+		n = os_write_file(fd, &mmop, sizeof(mmop));
+		if(n != sizeof(mmop))
+			panic("map_stub_pages : /proc/mm map for data failed, "
+			      "err = %d\n", -n);
+	}
+}
+
+void new_thread(void *stack, jmp_buf *buf, void (*handler)(void))
+{
+	(*buf)[0].JB_IP = (unsigned long) handler;
+	(*buf)[0].JB_SP = (unsigned long) stack +
+		(PAGE_SIZE << UML_CONFIG_KERNEL_STACK_ORDER) - sizeof(void *);
+}
+
+#define INIT_JMP_NEW_THREAD 0
+#define INIT_JMP_CALLBACK 1
+#define INIT_JMP_HALT 2
+#define INIT_JMP_REBOOT 3
+
+void switch_threads(jmp_buf *me, jmp_buf *you)
+{
+	if(UML_SETJMP(me) == 0)
+		UML_LONGJMP(you, 1);
+}
+
+static jmp_buf initial_jmpbuf;
+
+/* XXX Make these percpu */
+static void (*cb_proc)(void *arg);
+static void *cb_arg;
+static jmp_buf *cb_back;
+
+int start_idle_thread(void *stack, jmp_buf *switch_buf)
+{
+	int n;
+
+	set_handler(SIGWINCH, (__sighandler_t) sig_handler,
+		    SA_ONSTACK | SA_RESTART, SIGUSR1, SIGIO, SIGALRM,
+		    SIGVTALRM, -1);
+
+	n = UML_SETJMP(&initial_jmpbuf);
+	switch(n){
+	case INIT_JMP_NEW_THREAD:
+		(*switch_buf)[0].JB_IP = (unsigned long) new_thread_handler;
+		(*switch_buf)[0].JB_SP = (unsigned long) stack +
+			(PAGE_SIZE << UML_CONFIG_KERNEL_STACK_ORDER) -
+			sizeof(void *);
+		break;
+	case INIT_JMP_CALLBACK:
+		(*cb_proc)(cb_arg);
+		UML_LONGJMP(cb_back, 1);
+		break;
+	case INIT_JMP_HALT:
+		kmalloc_ok = 0;
+		return(0);
+	case INIT_JMP_REBOOT:
+		kmalloc_ok = 0;
+		return(1);
+	default:
+		panic("Bad sigsetjmp return in start_idle_thread - %d\n", n);
+	}
+	UML_LONGJMP(switch_buf, 1);
+}
+
+void initial_thread_cb_skas(void (*proc)(void *), void *arg)
+{
+	jmp_buf here;
+
+	cb_proc = proc;
+	cb_arg = arg;
+	cb_back = &here;
+
+	block_signals();
+	if(UML_SETJMP(&here) == 0)
+		UML_LONGJMP(&initial_jmpbuf, INIT_JMP_CALLBACK);
+	unblock_signals();
+
+	cb_proc = NULL;
+	cb_arg = NULL;
+	cb_back = NULL;
+}
+
+void halt_skas(void)
+{
+	block_signals();
+	UML_LONGJMP(&initial_jmpbuf, INIT_JMP_HALT);
+}
+
+void reboot_skas(void)
+{
+	block_signals();
+	UML_LONGJMP(&initial_jmpbuf, INIT_JMP_REBOOT);
+}
+
+void switch_mm_skas(struct mm_id *mm_idp)
+{
+	int err;
+
+#warning need cpu pid in switch_mm_skas
+	if(proc_mm){
+		err = ptrace(PTRACE_SWITCH_MM, userspace_pid[0], 0,
+			     mm_idp->u.mm_fd);
+		if(err)
+			panic("switch_mm_skas - PTRACE_SWITCH_MM failed, "
+			      "errno = %d\n", errno);
+	}
+	else userspace_pid[0] = mm_idp->u.pid;
+}

arch/um/os-Linux/skas/trap.c

@@ -0,0 +1,73 @@
+/*
+ * Copyright (C) 2002 - 2003 Jeff Dike (jdike@addtoit.com)
+ * Licensed under the GPL
+ */
+
+#include <signal.h>
+#include <errno.h>
+#include "user_util.h"
+#include "kern_util.h"
+#include "task.h"
+#include "sigcontext.h"
+#include "skas.h"
+#include "ptrace_user.h"
+#include "sysdep/ptrace.h"
+#include "sysdep/ptrace_user.h"
+#include "os.h"
+
+void sig_handler_common_skas(int sig, void *sc_ptr)
+{
+	struct sigcontext *sc = sc_ptr;
+	struct skas_regs *r;
+	void (*handler)(int, union uml_pt_regs *);
+	int save_errno = errno;
+	int save_user;
+
+	/* This is done because to allow SIGSEGV to be delivered inside a SEGV
+	 * handler.  This can happen in copy_user, and if SEGV is disabled,
+	 * the process will die.
+	 * XXX Figure out why this is better than SA_NODEFER
+	 */
+	if(sig == SIGSEGV)
+		change_sig(SIGSEGV, 1);
+
+	r = &TASK_REGS(get_current())->skas;
+	save_user = r->is_user;
+	r->is_user = 0;
+	if ( sig == SIGFPE || sig == SIGSEGV ||
+	     sig == SIGBUS || sig == SIGILL ||
+	     sig == SIGTRAP ) {
+		GET_FAULTINFO_FROM_SC(r->faultinfo, sc);
+	}
+
+	change_sig(SIGUSR1, 1);
+
+	handler = sig_info[sig];
+
+	/* unblock SIGALRM, SIGVTALRM, SIGIO if sig isn't IRQ signal */
+	if (sig != SIGIO && sig != SIGWINCH &&
+	    sig != SIGVTALRM && sig != SIGALRM)
+		unblock_signals();
+
+	handler(sig, (union uml_pt_regs *) r);
+
+	errno = save_errno;
+	r->is_user = save_user;
+}
+
+extern int ptrace_faultinfo;
+
+void user_signal(int sig, union uml_pt_regs *regs, int pid)
+{
+	void (*handler)(int, union uml_pt_regs *);
+	int segv = ((sig == SIGFPE) || (sig == SIGSEGV) || (sig == SIGBUS) ||
+		    (sig == SIGILL) || (sig == SIGTRAP));
+
+	if (segv)
+		get_skas_faultinfo(pid, &regs->skas.faultinfo);
+
+	handler = sig_info[sig];
+	handler(sig, (union uml_pt_regs *) regs);
+
+	unblock_signals();
+}

arch/um/os-Linux/start_up.c

@@ -0,0 +1,683 @@
+/*
+ * Copyright (C) 2000, 2001, 2002 Jeff Dike (jdike@karaya.com)
+ * Licensed under the GPL
+ */
+
+#include <pty.h>
+#include <stdio.h>
+#include <stddef.h>
+#include <stdarg.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <signal.h>
+#include <sched.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <sys/time.h>
+#include <sys/wait.h>
+#include <sys/mman.h>
+#include <asm/unistd.h>
+#include <asm/page.h>
+#include <sys/types.h>
+#include "user_util.h"
+#include "kern_util.h"
+#include "user.h"
+#include "signal_kern.h"
+#include "sysdep/ptrace.h"
+#include "sysdep/sigcontext.h"
+#include "irq_user.h"
+#include "ptrace_user.h"
+#include "mem_user.h"
+#include "init.h"
+#include "os.h"
+#include "uml-config.h"
+#include "choose-mode.h"
+#include "mode.h"
+#include "tempfile.h"
+#include "kern_constants.h"
+
+#ifdef UML_CONFIG_MODE_SKAS
+#include "skas.h"
+#include "skas_ptrace.h"
+#include "registers.h"
+#endif
+
+static int ptrace_child(void *arg)
+{
+	int ret;
+	int pid = os_getpid(), ppid = getppid();
+	int sc_result;
+
+	change_sig(SIGWINCH, 0);
+	if(ptrace(PTRACE_TRACEME, 0, 0, 0) < 0){
+		perror("ptrace");
+		os_kill_process(pid, 0);
+	}
+	kill(pid, SIGSTOP);
+
+	/*This syscall will be intercepted by the parent. Don't call more than
+	 * once, please.*/
+	sc_result = os_getpid();
+
+	if (sc_result == pid)
+		ret = 1; /*Nothing modified by the parent, we are running
+			   normally.*/
+	else if (sc_result == ppid)
+		ret = 0; /*Expected in check_ptrace and check_sysemu when they
+			   succeed in modifying the stack frame*/
+	else
+		ret = 2; /*Serious trouble! This could be caused by a bug in
+			   host 2.6 SKAS3/2.6 patch before release -V6, together
+			   with a bug in the UML code itself.*/
+	_exit(ret);
+}
+
+static void fatal_perror(char *str)
+{
+	perror(str);
+	exit(1);
+}
+
+static void fatal(char *fmt, ...)
+{
+	va_list list;
+
+	va_start(list, fmt);
+	vprintf(fmt, list);
+	va_end(list);
+	fflush(stdout);
+
+	exit(1);
+}
+
+static void non_fatal(char *fmt, ...)
+{
+	va_list list;
+
+	va_start(list, fmt);
+	vprintf(fmt, list);
+	va_end(list);
+	fflush(stdout);
+}
+
+static int start_ptraced_child(void **stack_out)
+{
+	void *stack;
+	unsigned long sp;
+	int pid, n, status;
+
+	stack = mmap(NULL, PAGE_SIZE, PROT_READ | PROT_WRITE | PROT_EXEC,
+		     MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+	if(stack == MAP_FAILED)
+		fatal_perror("check_ptrace : mmap failed");
+	sp = (unsigned long) stack + PAGE_SIZE - sizeof(void *);
+	pid = clone(ptrace_child, (void *) sp, SIGCHLD, NULL);
+	if(pid < 0)
+		fatal_perror("start_ptraced_child : clone failed");
+	CATCH_EINTR(n = waitpid(pid, &status, WUNTRACED));
+	if(n < 0)
+		fatal_perror("check_ptrace : clone failed");
+	if(!WIFSTOPPED(status) || (WSTOPSIG(status) != SIGSTOP))
+		fatal("check_ptrace : expected SIGSTOP, got status = %d",
+		      status);
+
+	*stack_out = stack;
+	return pid;
+}
+
+/* When testing for SYSEMU support, if it is one of the broken versions, we
+ * must just avoid using sysemu, not panic, but only if SYSEMU features are
+ * broken.
+ * So only for SYSEMU features we test mustpanic, while normal host features
+ * must work anyway!
+ */
+static int stop_ptraced_child(int pid, void *stack, int exitcode,
+			      int mustexit)
+{
+	int status, n, ret = 0;
+
+	if(ptrace(PTRACE_CONT, pid, 0, 0) < 0)
+		fatal_perror("stop_ptraced_child : ptrace failed");
+	CATCH_EINTR(n = waitpid(pid, &status, 0));
+	if(!WIFEXITED(status) || (WEXITSTATUS(status) != exitcode)) {
+		int exit_with = WEXITSTATUS(status);
+		if (exit_with == 2)
+			non_fatal("check_ptrace : child exited with status 2. "
+				  "\nDisabling SYSEMU support.\n");
+		non_fatal("check_ptrace : child exited with exitcode %d, while "
+			  "expecting %d; status 0x%x\n", exit_with,
+			  exitcode, status);
+		if (mustexit)
+			exit(1);
+		ret = -1;
+	}
+
+	if(munmap(stack, PAGE_SIZE) < 0)
+		fatal_perror("check_ptrace : munmap failed");
+	return ret;
+}
+
+/* Changed only during early boot */
+int ptrace_faultinfo = 1;
+int ptrace_ldt = 1;
+int proc_mm = 1;
+int skas_needs_stub = 0;
+
+static int __init skas0_cmd_param(char *str, int* add)
+{
+	ptrace_faultinfo = proc_mm = 0;
+	return 0;
+}
+
+/* The two __uml_setup would conflict, without this stupid alias. */
+
+static int __init mode_skas0_cmd_param(char *str, int* add)
+	__attribute__((alias("skas0_cmd_param")));
+
+__uml_setup("skas0", skas0_cmd_param,
+		"skas0\n"
+		"    Disables SKAS3 usage, so that SKAS0 is used, unless \n"
+	        "    you specify mode=tt.\n\n");
+
+__uml_setup("mode=skas0", mode_skas0_cmd_param,
+		"mode=skas0\n"
+		"    Disables SKAS3 usage, so that SKAS0 is used, unless you \n"
+		"    specify mode=tt. Note that this was recently added - on \n"
+		"    older kernels you must use simply \"skas0\".\n\n");
+
+/* Changed only during early boot */
+static int force_sysemu_disabled = 0;
+
+static int __init nosysemu_cmd_param(char *str, int* add)
+{
+	force_sysemu_disabled = 1;
+	return 0;
+}
+
+__uml_setup("nosysemu", nosysemu_cmd_param,
+"nosysemu\n"
+"    Turns off syscall emulation patch for ptrace (SYSEMU) on.\n"
+"    SYSEMU is a performance-patch introduced by Laurent Vivier. It changes\n"
+"    behaviour of ptrace() and helps reducing host context switch rate.\n"
+"    To make it working, you need a kernel patch for your host, too.\n"
+"    See http://perso.wanadoo.fr/laurent.vivier/UML/ for further \n"
+"    information.\n\n");
+
+static void __init check_sysemu(void)
+{
+	void *stack;
+	unsigned long regs[MAX_REG_NR];
+	int pid, n, status, count=0;
+
+	non_fatal("Checking syscall emulation patch for ptrace...");
+	sysemu_supported = 0;
+	pid = start_ptraced_child(&stack);
+
+	if(ptrace(PTRACE_SYSEMU, pid, 0, 0) < 0)
+		goto fail;
+
+	CATCH_EINTR(n = waitpid(pid, &status, WUNTRACED));
+	if (n < 0)
+		fatal_perror("check_sysemu : wait failed");
+	if(!WIFSTOPPED(status) || (WSTOPSIG(status) != SIGTRAP))
+		fatal("check_sysemu : expected SIGTRAP, got status = %d",
+		      status);
+
+	if(ptrace(PTRACE_GETREGS, pid, 0, regs) < 0)
+		fatal_perror("check_sysemu : PTRACE_GETREGS failed");
+	if(PT_SYSCALL_NR(regs) != __NR_getpid){
+		non_fatal("check_sysemu got system call number %d, "
+			  "expected %d...", PT_SYSCALL_NR(regs), __NR_getpid);
+		goto fail;
+	}
+
+	n = ptrace(PTRACE_POKEUSR, pid, PT_SYSCALL_RET_OFFSET, os_getpid());
+	if(n < 0){
+		non_fatal("check_sysemu : failed to modify system call "
+			  "return");
+		goto fail;
+	}
+
+	if (stop_ptraced_child(pid, stack, 0, 0) < 0)
+		goto fail_stopped;
+
+	sysemu_supported = 1;
+	non_fatal("OK\n");
+	set_using_sysemu(!force_sysemu_disabled);
+
+	non_fatal("Checking advanced syscall emulation patch for ptrace...");
+	pid = start_ptraced_child(&stack);
+
+	if((ptrace(PTRACE_OLDSETOPTIONS, pid, 0,
+		   (void *) PTRACE_O_TRACESYSGOOD) < 0))
+		fatal_perror("check_ptrace: PTRACE_OLDSETOPTIONS failed");
+
+	while(1){
+		count++;
+		if(ptrace(PTRACE_SYSEMU_SINGLESTEP, pid, 0, 0) < 0)
+			goto fail;
+		CATCH_EINTR(n = waitpid(pid, &status, WUNTRACED));
+		if(n < 0)
+			fatal_perror("check_ptrace : wait failed");
+
+		if(WIFSTOPPED(status) && (WSTOPSIG(status) == (SIGTRAP|0x80))){
+			if (!count)
+				fatal("check_ptrace : SYSEMU_SINGLESTEP "
+				      "doesn't singlestep");
+			n = ptrace(PTRACE_POKEUSR, pid, PT_SYSCALL_RET_OFFSET,
+				   os_getpid());
+			if(n < 0)
+				fatal_perror("check_sysemu : failed to modify "
+					     "system call return");
+			break;
+		}
+		else if(WIFSTOPPED(status) && (WSTOPSIG(status) == SIGTRAP))
+			count++;
+		else
+			fatal("check_ptrace : expected SIGTRAP or "
+			      "(SIGTRAP | 0x80), got status = %d", status);
+	}
+	if (stop_ptraced_child(pid, stack, 0, 0) < 0)
+		goto fail_stopped;
+
+	sysemu_supported = 2;
+	non_fatal("OK\n");
+
+	if ( !force_sysemu_disabled )
+		set_using_sysemu(sysemu_supported);
+	return;
+
+fail:
+	stop_ptraced_child(pid, stack, 1, 0);
+fail_stopped:
+	non_fatal("missing\n");
+}
+
+static void __init check_ptrace(void)
+{
+	void *stack;
+	int pid, syscall, n, status;
+
+	non_fatal("Checking that ptrace can change system call numbers...");
+	pid = start_ptraced_child(&stack);
+
+	if((ptrace(PTRACE_OLDSETOPTIONS, pid, 0,
+		   (void *) PTRACE_O_TRACESYSGOOD) < 0))
+		fatal_perror("check_ptrace: PTRACE_OLDSETOPTIONS failed");
+
+	while(1){
+		if(ptrace(PTRACE_SYSCALL, pid, 0, 0) < 0)
+			fatal_perror("check_ptrace : ptrace failed");
+
+		CATCH_EINTR(n = waitpid(pid, &status, WUNTRACED));
+		if(n < 0)
+			fatal_perror("check_ptrace : wait failed");
+
+		if(!WIFSTOPPED(status) ||
+		   (WSTOPSIG(status) != (SIGTRAP | 0x80)))
+			fatal("check_ptrace : expected (SIGTRAP|0x80), "
+			       "got status = %d", status);
+
+		syscall = ptrace(PTRACE_PEEKUSR, pid, PT_SYSCALL_NR_OFFSET,
+				 0);
+		if(syscall == __NR_getpid){
+			n = ptrace(PTRACE_POKEUSR, pid, PT_SYSCALL_NR_OFFSET,
+				   __NR_getppid);
+			if(n < 0)
+				fatal_perror("check_ptrace : failed to modify "
+					     "system call");
+			break;
+		}
+	}
+	stop_ptraced_child(pid, stack, 0, 1);
+	non_fatal("OK\n");
+	check_sysemu();
+}
+
+extern void check_tmpexec(void);
+
+void os_early_checks(void)
+{
+	check_ptrace();
+
+	/* Need to check this early because mmapping happens before the
+	 * kernel is running.
+	 */
+	check_tmpexec();
+}
+
+static int __init noprocmm_cmd_param(char *str, int* add)
+{
+	proc_mm = 0;
+	return 0;
+}
+
+__uml_setup("noprocmm", noprocmm_cmd_param,
+"noprocmm\n"
+"    Turns off usage of /proc/mm, even if host supports it.\n"
+"    To support /proc/mm, the host needs to be patched using\n"
+"    the current skas3 patch.\n\n");
+
+static int __init noptracefaultinfo_cmd_param(char *str, int* add)
+{
+	ptrace_faultinfo = 0;
+	return 0;
+}
+
+__uml_setup("noptracefaultinfo", noptracefaultinfo_cmd_param,
+"noptracefaultinfo\n"
+"    Turns off usage of PTRACE_FAULTINFO, even if host supports\n"
+"    it. To support PTRACE_FAULTINFO, the host needs to be patched\n"
+"    using the current skas3 patch.\n\n");
+
+static int __init noptraceldt_cmd_param(char *str, int* add)
+{
+	ptrace_ldt = 0;
+	return 0;
+}
+
+__uml_setup("noptraceldt", noptraceldt_cmd_param,
+"noptraceldt\n"
+"    Turns off usage of PTRACE_LDT, even if host supports it.\n"
+"    To support PTRACE_LDT, the host needs to be patched using\n"
+"    the current skas3 patch.\n\n");
+
+#ifdef UML_CONFIG_MODE_SKAS
+static inline void check_skas3_ptrace_faultinfo(void)
+{
+	struct ptrace_faultinfo fi;
+	void *stack;
+	int pid, n;
+
+	non_fatal("  - PTRACE_FAULTINFO...");
+	pid = start_ptraced_child(&stack);
+
+	n = ptrace(PTRACE_FAULTINFO, pid, 0, &fi);
+	if (n < 0) {
+		ptrace_faultinfo = 0;
+		if(errno == EIO)
+			non_fatal("not found\n");
+		else
+			perror("not found");
+	}
+	else {
+		if (!ptrace_faultinfo)
+			non_fatal("found but disabled on command line\n");
+		else
+			non_fatal("found\n");
+	}
+
+	init_registers(pid);
+	stop_ptraced_child(pid, stack, 1, 1);
+}
+
+static inline void check_skas3_ptrace_ldt(void)
+{
+#ifdef PTRACE_LDT
+	void *stack;
+	int pid, n;
+	unsigned char ldtbuf[40];
+	struct ptrace_ldt ldt_op = (struct ptrace_ldt) {
+		.func = 2, /* read default ldt */
+		.ptr = ldtbuf,
+		.bytecount = sizeof(ldtbuf)};
+
+	non_fatal("  - PTRACE_LDT...");
+	pid = start_ptraced_child(&stack);
+
+	n = ptrace(PTRACE_LDT, pid, 0, (unsigned long) &ldt_op);
+	if (n < 0) {
+		if(errno == EIO)
+			non_fatal("not found\n");
+		else {
+			perror("not found");
+		}
+		ptrace_ldt = 0;
+	}
+	else {
+		if(ptrace_ldt)
+			non_fatal("found\n");
+		else
+			non_fatal("found, but use is disabled\n");
+	}
+
+	stop_ptraced_child(pid, stack, 1, 1);
+#else
+	/* PTRACE_LDT might be disabled via cmdline option.
+	 * We want to override this, else we might use the stub
+	 * without real need
+	 */
+	ptrace_ldt = 1;
+#endif
+}
+
+static inline void check_skas3_proc_mm(void)
+{
+	non_fatal("  - /proc/mm...");
+	if (access("/proc/mm", W_OK) < 0) {
+		proc_mm = 0;
+		perror("not found");
+	}
+	else {
+		if (!proc_mm)
+			non_fatal("found but disabled on command line\n");
+		else
+			non_fatal("found\n");
+	}
+}
+
+int can_do_skas(void)
+{
+	non_fatal("Checking for the skas3 patch in the host:\n");
+
+	check_skas3_proc_mm();
+	check_skas3_ptrace_faultinfo();
+	check_skas3_ptrace_ldt();
+
+	if(!proc_mm || !ptrace_faultinfo || !ptrace_ldt)
+		skas_needs_stub = 1;
+
+	return 1;
+}
+#else
+int can_do_skas(void)
+{
+	return 0;
+}
+#endif
+
+int __init parse_iomem(char *str, int *add)
+{
+	struct iomem_region *new;
+	struct stat64 buf;
+	char *file, *driver;
+	int fd, size;
+
+	driver = str;
+	file = strchr(str,',');
+	if(file == NULL){
+		printf("parse_iomem : failed to parse iomem\n");
+		goto out;
+	}
+	*file = '\0';
+	file++;
+	fd = open(file, O_RDWR, 0);
+	if(fd < 0){
+		os_print_error(fd, "parse_iomem - Couldn't open io file");
+		goto out;
+	}
+
+	if(fstat64(fd, &buf) < 0){
+		perror("parse_iomem - cannot stat_fd file");
+		goto out_close;
+	}
+
+	new = malloc(sizeof(*new));
+	if(new == NULL){
+		perror("Couldn't allocate iomem_region struct");
+		goto out_close;
+	}
+
+	size = (buf.st_size + UM_KERN_PAGE_SIZE) & ~(UM_KERN_PAGE_SIZE - 1);
+
+	*new = ((struct iomem_region) { .next		= iomem_regions,
+					.driver		= driver,
+					.fd		= fd,
+					.size		= size,
+					.phys		= 0,
+					.virt		= 0 });
+	iomem_regions = new;
+	iomem_size += new->size + UM_KERN_PAGE_SIZE;
+
+	return 0;
+ out_close:
+	close(fd);
+ out:
+	return 1;
+}
+
+
+/* Changed during early boot */
+int pty_output_sigio = 0;
+int pty_close_sigio = 0;
+
+/* Used as a flag during SIGIO testing early in boot */
+static volatile int got_sigio = 0;
+
+static void __init handler(int sig)
+{
+	got_sigio = 1;
+}
+
+struct openpty_arg {
+	int master;
+	int slave;
+	int err;
+};
+
+static void openpty_cb(void *arg)
+{
+	struct openpty_arg *info = arg;
+
+	info->err = 0;
+	if(openpty(&info->master, &info->slave, NULL, NULL, NULL))
+		info->err = -errno;
+}
+
+static int async_pty(int master, int slave)
+{
+	int flags;
+
+	flags = fcntl(master, F_GETFL);
+	if(flags < 0)
+		return -errno;
+
+	if((fcntl(master, F_SETFL, flags | O_NONBLOCK | O_ASYNC) < 0) ||
+	   (fcntl(master, F_SETOWN, os_getpid()) < 0))
+		return -errno;
+
+	if((fcntl(slave, F_SETFL, flags | O_NONBLOCK) < 0))
+		return -errno;
+
+	return(0);
+}
+
+static void __init check_one_sigio(void (*proc)(int, int))
+{
+	struct sigaction old, new;
+	struct openpty_arg pty = { .master = -1, .slave = -1 };
+	int master, slave, err;
+
+	initial_thread_cb(openpty_cb, &pty);
+	if(pty.err){
+		printk("openpty failed, errno = %d\n", -pty.err);
+		return;
+	}
+
+	master = pty.master;
+	slave = pty.slave;
+
+	if((master == -1) || (slave == -1)){
+		printk("openpty failed to allocate a pty\n");
+		return;
+	}
+
+	/* Not now, but complain so we now where we failed. */
+	err = raw(master);
+	if (err < 0)
+		panic("check_sigio : __raw failed, errno = %d\n", -err);
+
+	err = async_pty(master, slave);
+	if(err < 0)
+		panic("tty_fds : sigio_async failed, err = %d\n", -err);
+
+	if(sigaction(SIGIO, NULL, &old) < 0)
+		panic("check_sigio : sigaction 1 failed, errno = %d\n", errno);
+	new = old;
+	new.sa_handler = handler;
+	if(sigaction(SIGIO, &new, NULL) < 0)
+		panic("check_sigio : sigaction 2 failed, errno = %d\n", errno);
+
+	got_sigio = 0;
+	(*proc)(master, slave);
+
+	close(master);
+	close(slave);
+
+	if(sigaction(SIGIO, &old, NULL) < 0)
+		panic("check_sigio : sigaction 3 failed, errno = %d\n", errno);
+}
+
+static void tty_output(int master, int slave)
+{
+	int n;
+	char buf[512];
+
+	printk("Checking that host ptys support output SIGIO...");
+
+	memset(buf, 0, sizeof(buf));
+
+	while(os_write_file(master, buf, sizeof(buf)) > 0) ;
+	if(errno != EAGAIN)
+		panic("check_sigio : write failed, errno = %d\n", errno);
+	while(((n = os_read_file(slave, buf, sizeof(buf))) > 0) && !got_sigio) ;
+
+	if(got_sigio){
+		printk("Yes\n");
+		pty_output_sigio = 1;
+	}
+	else if(n == -EAGAIN) printk("No, enabling workaround\n");
+	else panic("check_sigio : read failed, err = %d\n", n);
+}
+
+static void tty_close(int master, int slave)
+{
+	printk("Checking that host ptys support SIGIO on close...");
+
+	close(slave);
+	if(got_sigio){
+		printk("Yes\n");
+		pty_close_sigio = 1;
+	}
+	else printk("No, enabling workaround\n");
+}
+
+void __init check_sigio(void)
+{
+	if((os_access("/dev/ptmx", OS_ACC_R_OK) < 0) &&
+	   (os_access("/dev/ptyp0", OS_ACC_R_OK) < 0)){
+		printk("No pseudo-terminals available - skipping pty SIGIO "
+		       "check\n");
+		return;
+	}
+	check_one_sigio(tty_output);
+	check_one_sigio(tty_close);
+}
+
+void os_check_bugs(void)
+{
+	check_ptrace();
+	check_sigio();
+}
+

arch/um/os-Linux/sys-i386/Makefile

@@ -0,0 +1,10 @@
+#
+# Copyright (C) 2000 Jeff Dike (jdike@karaya.com)
+# Licensed under the GPL
+#
+
+obj-$(CONFIG_MODE_SKAS) = registers.o signal.o tls.o
+
+USER_OBJS := $(obj-y)
+
+include arch/um/scripts/Makefile.rules

arch/um/os-Linux/sys-i386/registers.c

@@ -0,0 +1,144 @@
+/*
+ * Copyright (C) 2004 PathScale, Inc
+ * Licensed under the GPL
+ */
+
+#include <errno.h>
+#include <string.h>
+#include "sysdep/ptrace_user.h"
+#include "sysdep/ptrace.h"
+#include "uml-config.h"
+#include "skas_ptregs.h"
+#include "registers.h"
+#include "longjmp.h"
+#include "user.h"
+
+/* These are set once at boot time and not changed thereafter */
+
+static unsigned long exec_regs[MAX_REG_NR];
+static unsigned long exec_fp_regs[HOST_FP_SIZE];
+static unsigned long exec_fpx_regs[HOST_XFP_SIZE];
+static int have_fpx_regs = 1;
+
+void init_thread_registers(union uml_pt_regs *to)
+{
+	memcpy(to->skas.regs, exec_regs, sizeof(to->skas.regs));
+	memcpy(to->skas.fp, exec_fp_regs, sizeof(to->skas.fp));
+	if(have_fpx_regs)
+		memcpy(to->skas.xfp, exec_fpx_regs, sizeof(to->skas.xfp));
+}
+
+/* XXX These need to use [GS]ETFPXREGS and copy_sc_{to,from}_user_skas needs
+ * to pass in a sufficiently large buffer
+ */
+int save_fp_registers(int pid, unsigned long *fp_regs)
+{
+	if(ptrace(PTRACE_GETFPREGS, pid, 0, fp_regs) < 0)
+		return -errno;
+	return 0;
+}
+
+int restore_fp_registers(int pid, unsigned long *fp_regs)
+{
+	if(ptrace(PTRACE_SETFPREGS, pid, 0, fp_regs) < 0)
+		return -errno;
+	return 0;
+}
+
+static int move_registers(int pid, int int_op, union uml_pt_regs *regs,
+			  int fp_op, unsigned long *fp_regs)
+{
+	if(ptrace(int_op, pid, 0, regs->skas.regs) < 0)
+		return -errno;
+
+	if(ptrace(fp_op, pid, 0, fp_regs) < 0)
+		return -errno;
+
+	return 0;
+}
+
+void save_registers(int pid, union uml_pt_regs *regs)
+{
+	unsigned long *fp_regs;
+	int err, fp_op;
+
+	if(have_fpx_regs){
+		fp_op = PTRACE_GETFPXREGS;
+		fp_regs = regs->skas.xfp;
+	}
+	else {
+		fp_op = PTRACE_GETFPREGS;
+		fp_regs = regs->skas.fp;
+	}
+
+	err = move_registers(pid, PTRACE_GETREGS, regs, fp_op, fp_regs);
+	if(err)
+		panic("save_registers - saving registers failed, errno = %d\n",
+		      -err);
+}
+
+void restore_registers(int pid, union uml_pt_regs *regs)
+{
+	unsigned long *fp_regs;
+	int err, fp_op;
+
+	if(have_fpx_regs){
+		fp_op = PTRACE_SETFPXREGS;
+		fp_regs = regs->skas.xfp;
+	}
+	else {
+		fp_op = PTRACE_SETFPREGS;
+		fp_regs = regs->skas.fp;
+	}
+
+	err = move_registers(pid, PTRACE_SETREGS, regs, fp_op, fp_regs);
+	if(err)
+		panic("restore_registers - saving registers failed, "
+		      "errno = %d\n", -err);
+}
+
+void init_registers(int pid)
+{
+	int err;
+
+	memset(exec_regs, 0, sizeof(exec_regs));
+	err = ptrace(PTRACE_GETREGS, pid, 0, exec_regs);
+	if(err)
+		panic("check_ptrace : PTRACE_GETREGS failed, errno = %d",
+		      errno);
+
+	errno = 0;
+	err = ptrace(PTRACE_GETFPXREGS, pid, 0, exec_fpx_regs);
+	if(!err)
+		return;
+	if(errno != EIO)
+		panic("check_ptrace : PTRACE_GETFPXREGS failed, errno = %d",
+		      errno);
+
+	have_fpx_regs = 0;
+
+	err = ptrace(PTRACE_GETFPREGS, pid, 0, exec_fp_regs);
+	if(err)
+		panic("check_ptrace : PTRACE_GETFPREGS failed, errno = %d",
+		      errno);
+}
+
+void get_safe_registers(unsigned long *regs, unsigned long *fp_regs)
+{
+	memcpy(regs, exec_regs, sizeof(exec_regs));
+	if(fp_regs != NULL)
+		memcpy(fp_regs, exec_fp_regs,
+		       HOST_FP_SIZE * sizeof(unsigned long));
+}
+
+unsigned long get_thread_reg(int reg, jmp_buf *buf)
+{
+	switch(reg){
+	case EIP: return buf[0]->__eip;
+	case UESP: return buf[0]->__esp;
+	case EBP: return buf[0]->__ebp;
+	default:
+		printk("get_thread_regs - unknown register %d\n", reg);
+		return 0;
+	}
+}

arch/um/os-Linux/sys-i386/signal.c

@@ -0,0 +1,15 @@
+/*
+ * Copyright (C) 2006 Jeff Dike (jdike@addtoit.com)
+ * Licensed under the GPL
+ */
+
+#include <signal.h>
+
+extern void (*handlers[])(int sig, struct sigcontext *sc);
+
+void hard_handler(int sig)
+{
+	struct sigcontext *sc = (struct sigcontext *) (&sig + 1);
+
+	(*handlers[sig])(sig, sc);
+}

arch/um/os-Linux/sys-i386/tls.c

@@ -0,0 +1,36 @@
+#include <errno.h>
+#include <linux/unistd.h>
+
+#include <sys/syscall.h>
+#include <unistd.h>
+
+#include "sysdep/tls.h"
+#include "user_util.h"
+
+/* Checks whether host supports TLS, and sets *tls_min according to the value
+ * valid on the host.
+ * i386 host have it == 6; x86_64 host have it == 12, for i386 emulation. */
+void check_host_supports_tls(int *supports_tls, int *tls_min) {
+	/* Values for x86 and x86_64.*/
+	int val[] = {GDT_ENTRY_TLS_MIN_I386, GDT_ENTRY_TLS_MIN_X86_64};
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(val); i++) {
+		user_desc_t info;
+		info.entry_number = val[i];
+
+		if (syscall(__NR_get_thread_area, &info) == 0) {
+			*tls_min = val[i];
+			*supports_tls = 1;
+			return;
+		} else {
+			if (errno == EINVAL)
+				continue;
+			else if (errno == ENOSYS)
+				*supports_tls = 0;
+				return;
+		}
+	}
+
+	*supports_tls = 0;
+}

arch/um/os-Linux/sys-x86_64/Makefile

@@ -0,0 +1,10 @@
+#
+# Copyright (C) 2000 Jeff Dike (jdike@karaya.com)
+# Licensed under the GPL
+#
+
+obj-$(CONFIG_MODE_SKAS) = registers.o prctl.o signal.o
+
+USER_OBJS := $(obj-y)
+
+include arch/um/scripts/Makefile.rules

arch/um/os-Linux/sys-x86_64/prctl.c

@@ -0,0 +1,12 @@
+/*
+ * Copyright (C) 2007 Jeff Dike (jdike@{addtoit.com,linux.intel.com})
+ * Licensed under the GPL
+ */
+
+#include <sys/ptrace.h>
+#include <linux/ptrace.h>
+
+int os_arch_prctl(int pid, int code, unsigned long *addr)
+{
+        return ptrace(PTRACE_ARCH_PRCTL, pid, (unsigned long) addr, code);
+}

arch/um/os-Linux/sys-x86_64/registers.c

@@ -0,0 +1,91 @@
+/*
+ * Copyright (C) 2004 PathScale, Inc
+ * Licensed under the GPL
+ */
+
+#include <errno.h>
+#include <string.h>
+#include "ptrace_user.h"
+#include "uml-config.h"
+#include "skas_ptregs.h"
+#include "registers.h"
+#include "longjmp.h"
+#include "user.h"
+
+/* These are set once at boot time and not changed thereafter */
+
+static unsigned long exec_regs[MAX_REG_NR];
+static unsigned long exec_fp_regs[HOST_FP_SIZE];
+
+void init_thread_registers(union uml_pt_regs *to)
+{
+	memcpy(to->skas.regs, exec_regs, sizeof(to->skas.regs));
+	memcpy(to->skas.fp, exec_fp_regs, sizeof(to->skas.fp));
+}
+
+static int move_registers(int pid, int int_op, int fp_op,
+			  union uml_pt_regs *regs)
+{
+	if(ptrace(int_op, pid, 0, regs->skas.regs) < 0)
+		return -errno;
+
+	if(ptrace(fp_op, pid, 0, regs->skas.fp) < 0)
+		return -errno;
+
+	return 0;
+}
+
+void save_registers(int pid, union uml_pt_regs *regs)
+{
+	int err;
+
+	err = move_registers(pid, PTRACE_GETREGS, PTRACE_GETFPREGS, regs);
+	if(err)
+		panic("save_registers - saving registers failed, errno = %d\n",
+		      -err);
+}
+
+void restore_registers(int pid, union uml_pt_regs *regs)
+{
+	int err;
+
+	err = move_registers(pid, PTRACE_SETREGS, PTRACE_SETFPREGS, regs);
+	if(err)
+		panic("restore_registers - saving registers failed, "
+		      "errno = %d\n", -err);
+}
+
+void init_registers(int pid)
+{
+	int err;
+
+	err = ptrace(PTRACE_GETREGS, pid, 0, exec_regs);
+	if(err)
+		panic("check_ptrace : PTRACE_GETREGS failed, errno = %d",
+		      errno);
+
+	err = ptrace(PTRACE_GETFPREGS, pid, 0, exec_fp_regs);
+	if(err)
+		panic("check_ptrace : PTRACE_GETFPREGS failed, errno = %d",
+		      errno);
+}
+
+void get_safe_registers(unsigned long *regs, unsigned long *fp_regs)
+{
+	memcpy(regs, exec_regs, sizeof(exec_regs));
+	if(fp_regs != NULL)
+		memcpy(fp_regs, exec_fp_regs,
+		       HOST_FP_SIZE * sizeof(unsigned long));
+}
+
+unsigned long get_thread_reg(int reg, jmp_buf *buf)
+{
+	switch(reg){
+	case RIP: return buf[0]->__rip;
+	case RSP: return buf[0]->__rsp;
+	case RBP: return buf[0]->__rbp;
+	default:
+		printk("get_thread_regs - unknown register %d\n", reg);
+		return 0;
+	}
+}

arch/um/os-Linux/sys-x86_64/signal.c

@@ -0,0 +1,16 @@
+/*
+ * Copyright (C) 2006 Jeff Dike (jdike@addtoit.com)
+ * Licensed under the GPL
+ */
+
+#include <signal.h>
+
+extern void (*handlers[])(int sig, struct sigcontext *sc);
+
+void hard_handler(int sig)
+{
+	struct ucontext *uc;
+	asm("movq %%rdx, %0" : "=r" (uc));
+
+	(*handlers[sig])(sig, (struct sigcontext *) &uc->uc_mcontext);
+}

arch/um/os-Linux/time.c

@@ -0,0 +1,102 @@
+/*
+ * Copyright (C) 2000, 2001, 2002 Jeff Dike (jdike@karaya.com)
+ * Licensed under the GPL
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <time.h>
+#include <sys/time.h>
+#include <signal.h>
+#include <errno.h>
+#include "user_util.h"
+#include "kern_util.h"
+#include "user.h"
+#include "process.h"
+#include "kern_constants.h"
+#include "os.h"
+#include "uml-config.h"
+
+int set_interval(int is_virtual)
+{
+	int usec = 1000000/hz();
+	int timer_type = is_virtual ? ITIMER_VIRTUAL : ITIMER_REAL;
+	struct itimerval interval = ((struct itimerval) { { 0, usec },
+							  { 0, usec } });
+
+	if(setitimer(timer_type, &interval, NULL) == -1)
+		return -errno;
+
+	return 0;
+}
+
+#ifdef UML_CONFIG_MODE_TT
+void enable_timer(void)
+{
+	set_interval(1);
+}
+#endif
+
+void disable_timer(void)
+{
+	struct itimerval disable = ((struct itimerval) { { 0, 0 }, { 0, 0 }});
+	if((setitimer(ITIMER_VIRTUAL, &disable, NULL) < 0) ||
+	   (setitimer(ITIMER_REAL, &disable, NULL) < 0))
+		printk("disnable_timer - setitimer failed, errno = %d\n",
+		       errno);
+	/* If there are signals already queued, after unblocking ignore them */
+	signal(SIGALRM, SIG_IGN);
+	signal(SIGVTALRM, SIG_IGN);
+}
+
+void switch_timers(int to_real)
+{
+	struct itimerval disable = ((struct itimerval) { { 0, 0 }, { 0, 0 }});
+	struct itimerval enable = ((struct itimerval) { { 0, 1000000/hz() },
+							{ 0, 1000000/hz() }});
+	int old, new;
+
+	if(to_real){
+		old = ITIMER_VIRTUAL;
+		new = ITIMER_REAL;
+	}
+	else {
+		old = ITIMER_REAL;
+		new = ITIMER_VIRTUAL;
+	}
+
+	if((setitimer(old, &disable, NULL) < 0) ||
+	   (setitimer(new, &enable, NULL)))
+		printk("switch_timers - setitimer failed, errno = %d\n",
+		       errno);
+}
+
+#ifdef UML_CONFIG_MODE_TT
+void uml_idle_timer(void)
+{
+	if(signal(SIGVTALRM, SIG_IGN) == SIG_ERR)
+		panic("Couldn't unset SIGVTALRM handler");
+
+	set_handler(SIGALRM, (__sighandler_t) alarm_handler,
+		    SA_RESTART, SIGUSR1, SIGIO, SIGWINCH, SIGVTALRM, -1);
+	set_interval(0);
+}
+#endif
+
+unsigned long long os_nsecs(void)
+{
+	struct timeval tv;
+
+	gettimeofday(&tv, NULL);
+	return((unsigned long long) tv.tv_sec * BILLION + tv.tv_usec * 1000);
+}
+
+void idle_sleep(int secs)
+{
+	struct timespec ts;
+
+	ts.tv_sec = secs;
+	ts.tv_nsec = 0;
+	nanosleep(&ts, NULL);
+}

arch/um/os-Linux/tls.c

@@ -0,0 +1,75 @@
+#include <errno.h>
+#include <unistd.h>
+#include <sys/ptrace.h>
+#include <sys/syscall.h>
+#include <asm/ldt.h>
+#include "sysdep/tls.h"
+#include "uml-config.h"
+
+/* TLS support - we basically rely on the host's one.*/
+
+/* In TT mode, this should be called only by the tracing thread, and makes sense
+ * only for PTRACE_SET_THREAD_AREA. In SKAS mode, it's used normally.
+ *
+ */
+
+#ifndef PTRACE_GET_THREAD_AREA
+#define PTRACE_GET_THREAD_AREA 25
+#endif
+
+#ifndef PTRACE_SET_THREAD_AREA
+#define PTRACE_SET_THREAD_AREA 26
+#endif
+
+int os_set_thread_area(user_desc_t *info, int pid)
+{
+	int ret;
+
+	ret = ptrace(PTRACE_SET_THREAD_AREA, pid, info->entry_number,
+		     (unsigned long) info);
+	if (ret < 0)
+		ret = -errno;
+	return ret;
+}
+
+#ifdef UML_CONFIG_MODE_SKAS
+
+int os_get_thread_area(user_desc_t *info, int pid)
+{
+	int ret;
+
+	ret = ptrace(PTRACE_GET_THREAD_AREA, pid, info->entry_number,
+		     (unsigned long) info);
+	if (ret < 0)
+		ret = -errno;
+	return ret;
+}
+
+#endif
+
+#ifdef UML_CONFIG_MODE_TT
+#include "linux/unistd.h"
+
+int do_set_thread_area_tt(user_desc_t *info)
+{
+	int ret;
+
+	ret = syscall(__NR_set_thread_area,info);
+	if (ret < 0) {
+		ret = -errno;
+	}
+	return ret;
+}
+
+int do_get_thread_area_tt(user_desc_t *info)
+{
+	int ret;
+
+	ret = syscall(__NR_get_thread_area,info);
+	if (ret < 0) {
+		ret = -errno;
+	}
+	return ret;
+}
+
+#endif /* UML_CONFIG_MODE_TT */

arch/um/os-Linux/trap.c

@@ -0,0 +1,41 @@
+/*
+ * Copyright (C) 2000, 2001, 2002 Jeff Dike (jdike@karaya.com)
+ * Licensed under the GPL
+ */
+
+#include <stdlib.h>
+#include <signal.h>
+#include "kern_util.h"
+#include "user_util.h"
+#include "os.h"
+#include "mode.h"
+#include "longjmp.h"
+
+void usr2_handler(int sig, union uml_pt_regs *regs)
+{
+	CHOOSE_MODE(syscall_handler_tt(sig, regs), (void) 0);
+}
+
+/* Initialized from linux_main() */
+void (*sig_info[NSIG])(int, union uml_pt_regs *);
+
+void os_fill_handlinfo(struct kern_handlers h)
+{
+	sig_info[SIGTRAP] = h.relay_signal;
+	sig_info[SIGFPE] = h.relay_signal;
+	sig_info[SIGILL] = h.relay_signal;
+	sig_info[SIGWINCH] = h.winch;
+	sig_info[SIGBUS] = h.bus_handler;
+	sig_info[SIGSEGV] = h.page_fault;
+	sig_info[SIGIO] = h.sigio_handler;
+	sig_info[SIGVTALRM] = h.timer_handler;
+	sig_info[SIGALRM] = h.timer_handler;
+	sig_info[SIGUSR2] = usr2_handler;
+}
+
+void do_longjmp(void *b, int val)
+{
+	jmp_buf *buf = b;
+
+	UML_LONGJMP(buf, val);
+}

arch/um/os-Linux/tt.c

@@ -0,0 +1,196 @@
+/*
+ * Copyright (C) 2000, 2001, 2002 Jeff Dike (jdike@karaya.com)
+ * Licensed under the GPL
+ */
+
+#include <stdio.h>
+#include <unistd.h>
+#include <signal.h>
+#include <sched.h>
+#include <errno.h>
+#include <stdarg.h>
+#include <stdlib.h>
+#include <sys/time.h>
+#include <sys/ptrace.h>
+#include <linux/ptrace.h>
+#include <sys/wait.h>
+#include <sys/mman.h>
+#include <asm/ptrace.h>
+#include <asm/unistd.h>
+#include <asm/page.h>
+#include "user_util.h"
+#include "kern_util.h"
+#include "user.h"
+#include "signal_kern.h"
+#include "sysdep/ptrace.h"
+#include "sysdep/sigcontext.h"
+#include "irq_user.h"
+#include "ptrace_user.h"
+#include "init.h"
+#include "os.h"
+#include "uml-config.h"
+#include "choose-mode.h"
+#include "mode.h"
+#include "tempfile.h"
+
+int protect_memory(unsigned long addr, unsigned long len, int r, int w, int x,
+		   int must_succeed)
+{
+	int err;
+
+	err = os_protect_memory((void *) addr, len, r, w, x);
+	if(err < 0){
+                if(must_succeed)
+			panic("protect failed, err = %d", -err);
+		else return(err);
+	}
+	return(0);
+}
+
+void kill_child_dead(int pid)
+{
+	kill(pid, SIGKILL);
+	kill(pid, SIGCONT);
+	do {
+		int n;
+		CATCH_EINTR(n = waitpid(pid, NULL, 0));
+		if (n > 0)
+			kill(pid, SIGCONT);
+		else
+			break;
+	} while(1);
+}
+
+void stop(void)
+{
+	while(1) sleep(1000000);
+}
+
+int wait_for_stop(int pid, int sig, int cont_type, void *relay)
+{
+	sigset_t *relay_signals = relay;
+	int status, ret;
+
+	while(1){
+		CATCH_EINTR(ret = waitpid(pid, &status, WUNTRACED));
+		if((ret < 0) ||
+		   !WIFSTOPPED(status) || (WSTOPSIG(status) != sig)){
+			if(ret < 0){
+				printk("wait failed, errno = %d\n",
+				       errno);
+			}
+			else if(WIFEXITED(status))
+				printk("process %d exited with status %d\n",
+				       pid, WEXITSTATUS(status));
+			else if(WIFSIGNALED(status))
+				printk("process %d exited with signal %d\n",
+				       pid, WTERMSIG(status));
+			else if((WSTOPSIG(status) == SIGVTALRM) ||
+				(WSTOPSIG(status) == SIGALRM) ||
+				(WSTOPSIG(status) == SIGIO) ||
+				(WSTOPSIG(status) == SIGPROF) ||
+				(WSTOPSIG(status) == SIGCHLD) ||
+				(WSTOPSIG(status) == SIGWINCH) ||
+				(WSTOPSIG(status) == SIGINT)){
+				ptrace(cont_type, pid, 0, WSTOPSIG(status));
+				continue;
+			}
+			else if((relay_signals != NULL) &&
+				sigismember(relay_signals, WSTOPSIG(status))){
+				ptrace(cont_type, pid, 0, WSTOPSIG(status));
+				continue;
+			}
+			else printk("process %d stopped with signal %d\n",
+				    pid, WSTOPSIG(status));
+			panic("wait_for_stop failed to wait for %d to stop "
+			      "with %d\n", pid, sig);
+		}
+		return(status);
+	}
+}
+
+void forward_ipi(int fd, int pid)
+{
+	int err;
+
+	err = os_set_owner(fd, pid);
+	if(err < 0)
+		printk("forward_ipi: set_owner failed, fd = %d, me = %d, "
+		       "target = %d, err = %d\n", fd, os_getpid(), pid, -err);
+}
+
+/*
+ *-------------------------
+ * only for tt mode (will be deleted in future...)
+ *-------------------------
+ */
+
+struct tramp {
+	int (*tramp)(void *);
+	void *tramp_data;
+	unsigned long temp_stack;
+	int flags;
+	int pid;
+};
+
+/* See above for why sigkill is here */
+
+int sigkill = SIGKILL;
+
+int outer_tramp(void *arg)
+{
+	struct tramp *t;
+	int sig = sigkill;
+
+	t = arg;
+	t->pid = clone(t->tramp, (void *) t->temp_stack + page_size()/2,
+		       t->flags, t->tramp_data);
+	if(t->pid > 0) wait_for_stop(t->pid, SIGSTOP, PTRACE_CONT, NULL);
+	kill(os_getpid(), sig);
+	_exit(0);
+}
+
+int start_fork_tramp(void *thread_arg, unsigned long temp_stack,
+		     int clone_flags, int (*tramp)(void *))
+{
+	struct tramp arg;
+	unsigned long sp;
+	int new_pid, status, err;
+
+	/* The trampoline will run on the temporary stack */
+	sp = stack_sp(temp_stack);
+
+	clone_flags |= CLONE_FILES | SIGCHLD;
+
+	arg.tramp = tramp;
+	arg.tramp_data = thread_arg;
+	arg.temp_stack = temp_stack;
+	arg.flags = clone_flags;
+
+	/* Start the process and wait for it to kill itself */
+	new_pid = clone(outer_tramp, (void *) sp, clone_flags, &arg);
+	if(new_pid < 0)
+		return(new_pid);
+
+	CATCH_EINTR(err = waitpid(new_pid, &status, 0));
+	if(err < 0)
+		panic("Waiting for outer trampoline failed - errno = %d",
+		      errno);
+
+	if(!WIFSIGNALED(status) || (WTERMSIG(status) != SIGKILL))
+		panic("outer trampoline didn't exit with SIGKILL, "
+		      "status = %d", status);
+
+	return(arg.pid);
+}
+
+void forward_pending_sigio(int target)
+{
+	sigset_t sigs;
+
+	if(sigpending(&sigs))
+		panic("forward_pending_sigio : sigpending failed");
+	if(sigismember(&sigs, SIGIO))
+		kill(target, SIGIO);
+}
+

arch/um/os-Linux/tty.c

@@ -0,0 +1,61 @@
+/* 
+ * Copyright (C) 2002 Jeff Dike (jdike@karaya.com)
+ * Licensed under the GPL
+ */
+
+#include <stdlib.h>
+#include <errno.h>
+#include "os.h"
+#include "user.h"
+#include "kern_util.h"
+
+struct grantpt_info {
+	int fd;
+	int res;
+	int err;
+};
+
+static void grantpt_cb(void *arg)
+{
+	struct grantpt_info *info = arg;
+
+	info->res = grantpt(info->fd);
+	info->err = errno;
+}
+
+int get_pty(void)
+{
+	struct grantpt_info info;
+	int fd;
+
+	fd = os_open_file("/dev/ptmx", of_rdwr(OPENFLAGS()), 0);
+	if(fd < 0){
+		printk("get_pty : Couldn't open /dev/ptmx - err = %d\n", -fd);
+		return(fd);
+	}
+
+	info.fd = fd;
+	initial_thread_cb(grantpt_cb, &info);
+
+	if(info.res < 0){
+		printk("get_pty : Couldn't grant pty - errno = %d\n", 
+		       -info.err);
+		return(-1);
+	}
+	if(unlockpt(fd) < 0){
+		printk("get_pty : Couldn't unlock pty - errno = %d\n", errno);
+		return(-1);
+	}
+	return(fd);
+}
+
+/*
+ * Overrides for Emacs so that we follow Linus's tabbing style.
+ * Emacs will notice this stuff at the end of the file and automatically
+ * adjust the settings for this buffer only.  This must remain at the end
+ * of the file.
+ * ---------------------------------------------------------------------------
+ * Local variables:
+ * c-file-style: "linux"
+ * End:
+ */

arch/um/os-Linux/tty_log.c

@@ -0,0 +1,218 @@
+/*
+ * Copyright (C) 2002 Jeff Dike (jdike@karaya.com) and
+ * geoffrey hing <ghing@net.ohio-state.edu>
+ * Licensed under the GPL
+ */
+
+#include <errno.h>
+#include <string.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <sys/time.h>
+#include "init.h"
+#include "user.h"
+#include "kern_util.h"
+#include "os.h"
+
+#define TTY_LOG_DIR "./"
+
+/* Set early in boot and then unchanged */
+static char *tty_log_dir = TTY_LOG_DIR;
+static int tty_log_fd = -1;
+
+#define TTY_LOG_OPEN 1
+#define TTY_LOG_CLOSE 2
+#define TTY_LOG_WRITE 3
+#define TTY_LOG_EXEC 4
+
+#define TTY_READ 1
+#define TTY_WRITE 2
+
+struct tty_log_buf {
+	int what;
+	unsigned long tty;
+	int len;
+	int direction;
+	unsigned long sec;
+	unsigned long usec;
+};
+
+int open_tty_log(void *tty, void *current_tty)
+{
+	struct timeval tv;
+	struct tty_log_buf data;
+	char buf[strlen(tty_log_dir) + sizeof("01234567890-01234567\0")];
+	int fd;
+
+	gettimeofday(&tv, NULL);
+	if(tty_log_fd != -1){
+		data = ((struct tty_log_buf) { .what 	= TTY_LOG_OPEN,
+					       .tty  = (unsigned long) tty,
+					       .len  = sizeof(current_tty),
+					       .direction = 0,
+					       .sec = tv.tv_sec,
+					       .usec = tv.tv_usec } );
+		os_write_file(tty_log_fd, &data, sizeof(data));
+		os_write_file(tty_log_fd, &current_tty, data.len);
+		return(tty_log_fd);
+	}
+
+	sprintf(buf, "%s/%0u-%0u", tty_log_dir, (unsigned int) tv.tv_sec,
+ 		(unsigned int) tv.tv_usec);
+
+	fd = os_open_file(buf, of_append(of_create(of_rdwr(OPENFLAGS()))),
+			  0644);
+	if(fd < 0){
+		printk("open_tty_log : couldn't open '%s', errno = %d\n",
+		       buf, -fd);
+	}
+	return(fd);
+}
+
+void close_tty_log(int fd, void *tty)
+{
+	struct tty_log_buf data;
+	struct timeval tv;
+
+	if(tty_log_fd != -1){
+		gettimeofday(&tv, NULL);
+		data = ((struct tty_log_buf) { .what 	= TTY_LOG_CLOSE,
+					       .tty  = (unsigned long) tty,
+					       .len  = 0,
+					       .direction = 0,
+					       .sec = tv.tv_sec,
+					       .usec = tv.tv_usec } );
+		os_write_file(tty_log_fd, &data, sizeof(data));
+		return;
+	}
+	os_close_file(fd);
+}
+
+static int log_chunk(int fd, const char *buf, int len)
+{
+	int total = 0, try, missed, n;
+	char chunk[64];
+
+	while(len > 0){
+		try = (len > sizeof(chunk)) ? sizeof(chunk) : len;
+		missed = copy_from_user_proc(chunk, (char *) buf, try);
+		try -= missed;
+		n = os_write_file(fd, chunk, try);
+		if(n != try) {
+			if(n < 0)
+				return(n);
+			return(-EIO);
+		}
+		if(missed != 0)
+			return(-EFAULT);
+
+		len -= try;
+		total += try;
+		buf += try;
+	}
+
+	return(total);
+}
+
+int write_tty_log(int fd, const char *buf, int len, void *tty, int is_read)
+{
+	struct timeval tv;
+	struct tty_log_buf data;
+	int direction;
+
+	if(fd == tty_log_fd){
+		gettimeofday(&tv, NULL);
+		direction = is_read ? TTY_READ : TTY_WRITE;
+		data = ((struct tty_log_buf) { .what 	= TTY_LOG_WRITE,
+					       .tty  = (unsigned long) tty,
+					       .len  = len,
+					       .direction = direction,
+					       .sec = tv.tv_sec,
+					       .usec = tv.tv_usec } );
+		os_write_file(tty_log_fd, &data, sizeof(data));
+	}
+
+	return(log_chunk(fd, buf, len));
+}
+
+void log_exec(char **argv, void *tty)
+{
+	struct timeval tv;
+	struct tty_log_buf data;
+	char **ptr,*arg;
+	int len;
+
+	if(tty_log_fd == -1) return;
+
+	gettimeofday(&tv, NULL);
+
+	len = 0;
+	for(ptr = argv; ; ptr++){
+		if(copy_from_user_proc(&arg, ptr, sizeof(arg)))
+			return;
+		if(arg == NULL) break;
+		len += strlen_user_proc(arg);
+	}
+
+	data = ((struct tty_log_buf) { .what 	= TTY_LOG_EXEC,
+				       .tty  = (unsigned long) tty,
+				       .len  = len,
+				       .direction = 0,
+				       .sec = tv.tv_sec,
+				       .usec = tv.tv_usec } );
+	os_write_file(tty_log_fd, &data, sizeof(data));
+
+	for(ptr = argv; ; ptr++){
+		if(copy_from_user_proc(&arg, ptr, sizeof(arg)))
+			return;
+		if(arg == NULL) break;
+		log_chunk(tty_log_fd, arg, strlen_user_proc(arg));
+	}
+}
+
+extern void register_tty_logger(int (*opener)(void *, void *),
+				int (*writer)(int, const char *, int,
+					      void *, int),
+				void (*closer)(int, void *));
+
+static int register_logger(void)
+{
+	register_tty_logger(open_tty_log, write_tty_log, close_tty_log);
+	return(0);
+}
+
+__uml_initcall(register_logger);
+
+static int __init set_tty_log_dir(char *name, int *add)
+{
+	tty_log_dir = name;
+	return 0;
+}
+
+__uml_setup("tty_log_dir=", set_tty_log_dir,
+"tty_log_dir=<directory>\n"
+"    This is used to specify the directory where the logs of all pty\n"
+"    data from this UML machine will be written.\n\n"
+);
+
+static int __init set_tty_log_fd(char *name, int *add)
+{
+	char *end;
+
+	tty_log_fd = strtoul(name, &end, 0);
+	if((*end != '\0') || (end == name)){
+		printf("set_tty_log_fd - strtoul failed on '%s'\n", name);
+		tty_log_fd = -1;
+	}
+
+	*add = 0;
+	return 0;
+}
+
+__uml_setup("tty_log_fd=", set_tty_log_fd,
+"tty_log_fd=<fd>\n"
+"    This is used to specify a preconfigured file descriptor to which all\n"
+"    tty data will be written.  Preconfigure the descriptor with something\n"
+"    like '10>tty_log tty_log_fd=10'.\n\n"
+);

arch/um/os-Linux/uaccess.c

@@ -0,0 +1,32 @@
+/*
+ * Copyright (C) 2001 Chris Emerson (cemerson@chiark.greenend.org.uk)
+ * Copyright (C) 2001, 2002 Jeff Dike (jdike@karaya.com)
+ * Licensed under the GPL
+ */
+
+#include <stddef.h>
+#include "longjmp.h"
+
+unsigned long __do_user_copy(void *to, const void *from, int n,
+			     void **fault_addr, void **fault_catcher,
+			     void (*op)(void *to, const void *from,
+					int n), int *faulted_out)
+{
+	unsigned long *faddrp = (unsigned long *) fault_addr, ret;
+
+	jmp_buf jbuf;
+	*fault_catcher = &jbuf;
+	if(UML_SETJMP(&jbuf) == 0){
+		(*op)(to, from, n);
+		ret = 0;
+		*faulted_out = 0;
+	}
+	else {
+		ret = *faddrp;
+		*faulted_out = 1;
+	}
+	*fault_addr = NULL;
+	*fault_catcher = NULL;
+	return ret;
+}
+

arch/um/os-Linux/umid.c

@@ -0,0 +1,385 @@
+#include <stdio.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+#include <signal.h>
+#include <dirent.h>
+#include <sys/fcntl.h>
+#include <sys/stat.h>
+#include <sys/param.h>
+#include "init.h"
+#include "os.h"
+#include "user.h"
+#include "mode.h"
+
+#define UML_DIR "~/.uml/"
+
+#define UMID_LEN 64
+
+/* Changed by set_umid, which is run early in boot */
+static char umid[UMID_LEN] = { 0 };
+
+/* Changed by set_uml_dir and make_uml_dir, which are run early in boot */
+static char *uml_dir = UML_DIR;
+
+static int __init make_uml_dir(void)
+{
+	char dir[512] = { '\0' };
+	int len, err;
+
+	if(*uml_dir == '~'){
+		char *home = getenv("HOME");
+
+		err = -ENOENT;
+		if(home == NULL){
+			printk("make_uml_dir : no value in environment for "
+			       "$HOME\n");
+			goto err;
+		}
+		strlcpy(dir, home, sizeof(dir));
+		uml_dir++;
+	}
+	strlcat(dir, uml_dir, sizeof(dir));
+	len = strlen(dir);
+	if (len > 0 && dir[len - 1] != '/')
+		strlcat(dir, "/", sizeof(dir));
+
+	err = -ENOMEM;
+	uml_dir = malloc(strlen(dir) + 1);
+	if (uml_dir == NULL) {
+		printf("make_uml_dir : malloc failed, errno = %d\n", errno);
+		goto err;
+	}
+	strcpy(uml_dir, dir);
+
+	if((mkdir(uml_dir, 0777) < 0) && (errno != EEXIST)){
+	        printf("Failed to mkdir '%s': %s\n", uml_dir, strerror(errno));
+		err = -errno;
+		goto err_free;
+	}
+	return 0;
+
+err_free:
+	free(uml_dir);
+err:
+	uml_dir = NULL;
+	return err;
+}
+
+/*
+ * Unlinks the files contained in @dir and then removes @dir.
+ * Doesn't handle directory trees, so it's not like rm -rf, but almost such. We
+ * ignore ENOENT errors for anything (they happen, strangely enough - possibly due
+ * to races between multiple dying UML threads).
+ */
+static int remove_files_and_dir(char *dir)
+{
+	DIR *directory;
+	struct dirent *ent;
+	int len;
+	char file[256];
+	int ret;
+
+	directory = opendir(dir);
+	if (directory == NULL) {
+		if (errno != ENOENT)
+			return -errno;
+		else
+			return 0;
+	}
+
+	while ((ent = readdir(directory)) != NULL) {
+		if (!strcmp(ent->d_name, ".") || !strcmp(ent->d_name, ".."))
+			continue;
+		len = strlen(dir) + sizeof("/") + strlen(ent->d_name) + 1;
+		if (len > sizeof(file)) {
+			ret = -E2BIG;
+			goto out;
+		}
+
+		sprintf(file, "%s/%s", dir, ent->d_name);
+		if (unlink(file) < 0 && errno != ENOENT) {
+			ret = -errno;
+			goto out;
+		}
+	}
+
+	if (rmdir(dir) < 0 && errno != ENOENT) {
+		ret = -errno;
+		goto out;
+	}
+
+	ret = 0;
+out:
+	closedir(directory);
+	return ret;
+}
+
+/* This says that there isn't already a user of the specified directory even if
+ * there are errors during the checking.  This is because if these errors
+ * happen, the directory is unusable by the pre-existing UML, so we might as
+ * well take it over.  This could happen either by
+ * 	the existing UML somehow corrupting its umid directory
+ * 	something other than UML sticking stuff in the directory
+ *	this boot racing with a shutdown of the other UML
+ * In any of these cases, the directory isn't useful for anything else.
+ *
+ * Boolean return: 1 if in use, 0 otherwise.
+ */
+static inline int is_umdir_used(char *dir)
+{
+	char file[strlen(uml_dir) + UMID_LEN + sizeof("/pid\0")];
+	char pid[sizeof("nnnnn\0")], *end;
+	int dead, fd, p, n, err;
+
+	n = snprintf(file, sizeof(file), "%s/pid", dir);
+	if(n >= sizeof(file)){
+		printk("is_umdir_used - pid filename too long\n");
+		err = -E2BIG;
+		goto out;
+	}
+
+	dead = 0;
+	fd = open(file, O_RDONLY);
+	if(fd < 0) {
+		fd = -errno;
+		if(fd != -ENOENT){
+			printk("is_umdir_used : couldn't open pid file '%s', "
+			       "err = %d\n", file, -fd);
+		}
+		goto out;
+	}
+
+	err = 0;
+	n = read(fd, pid, sizeof(pid));
+	if(n < 0){
+		printk("is_umdir_used : couldn't read pid file '%s', "
+		       "err = %d\n", file, errno);
+		goto out_close;
+	} else if(n == 0){
+		printk("is_umdir_used : couldn't read pid file '%s', "
+		       "0-byte read\n", file);
+		goto out_close;
+	}
+
+	p = strtoul(pid, &end, 0);
+	if(end == pid){
+		printk("is_umdir_used : couldn't parse pid file '%s', "
+		       "errno = %d\n", file, errno);
+		goto out_close;
+	}
+
+	if((kill(p, 0) == 0) || (errno != ESRCH)){
+		printk("umid \"%s\" is already in use by pid %d\n", umid, p);
+		return 1;
+	}
+
+out_close:
+	close(fd);
+out:
+	return 0;
+}
+
+/*
+ * Try to remove the directory @dir unless it's in use.
+ * Precondition: @dir exists.
+ * Returns 0 for success, < 0 for failure in removal or if the directory is in
+ * use.
+ */
+static int umdir_take_if_dead(char *dir)
+{
+	int ret;
+	if (is_umdir_used(dir))
+		return -EEXIST;
+
+	ret = remove_files_and_dir(dir);
+	if (ret) {
+		printk("is_umdir_used - remove_files_and_dir failed with "
+		       "err = %d\n", ret);
+	}
+	return ret;
+}
+
+static void __init create_pid_file(void)
+{
+	char file[strlen(uml_dir) + UMID_LEN + sizeof("/pid\0")];
+	char pid[sizeof("nnnnn\0")];
+	int fd, n;
+
+	if(umid_file_name("pid", file, sizeof(file)))
+		return;
+
+	fd = open(file, O_RDWR | O_CREAT | O_EXCL, 0644);
+	if(fd < 0){
+		printk("Open of machine pid file \"%s\" failed: %s\n",
+		       file, strerror(errno));
+		return;
+	}
+
+	snprintf(pid, sizeof(pid), "%d\n", getpid());
+	n = write(fd, pid, strlen(pid));
+	if(n != strlen(pid))
+		printk("Write of pid file failed - err = %d\n", errno);
+
+	close(fd);
+}
+
+int __init set_umid(char *name)
+{
+	if(strlen(name) > UMID_LEN - 1)
+		return -E2BIG;
+
+	strlcpy(umid, name, sizeof(umid));
+
+	return 0;
+}
+
+/* Changed in make_umid, which is called during early boot */
+static int umid_setup = 0;
+
+int __init make_umid(void)
+{
+	int fd, err;
+	char tmp[256];
+
+	if(umid_setup)
+		return 0;
+
+	make_uml_dir();
+
+	if(*umid == '\0'){
+		strlcpy(tmp, uml_dir, sizeof(tmp));
+		strlcat(tmp, "XXXXXX", sizeof(tmp));
+		fd = mkstemp(tmp);
+		if(fd < 0){
+			printk("make_umid - mkstemp(%s) failed: %s\n",
+			       tmp, strerror(errno));
+			err = -errno;
+			goto err;
+		}
+
+		close(fd);
+
+		set_umid(&tmp[strlen(uml_dir)]);
+
+		/* There's a nice tiny little race between this unlink and
+		 * the mkdir below.  It'd be nice if there were a mkstemp
+		 * for directories.
+		 */
+		if(unlink(tmp)){
+			err = -errno;
+			goto err;
+		}
+	}
+
+	snprintf(tmp, sizeof(tmp), "%s%s", uml_dir, umid);
+	err = mkdir(tmp, 0777);
+	if(err < 0){
+		err = -errno;
+		if(err != -EEXIST)
+			goto err;
+
+		if (umdir_take_if_dead(tmp) < 0)
+			goto err;
+
+		err = mkdir(tmp, 0777);
+	}
+	if(err){
+		err = -errno;
+		printk("Failed to create '%s' - err = %d\n", umid, -errno);
+		goto err;
+	}
+
+	umid_setup = 1;
+
+	create_pid_file();
+
+	err = 0;
+ err:
+	return err;
+}
+
+static int __init make_umid_init(void)
+{
+	if(!make_umid())
+		return 0;
+
+	/* If initializing with the given umid failed, then try again with
+	 * a random one.
+	 */
+	printk("Failed to initialize umid \"%s\", trying with a random umid\n",
+	       umid);
+	*umid = '\0';
+	make_umid();
+
+	return 0;
+}
+
+__initcall(make_umid_init);
+
+int __init umid_file_name(char *name, char *buf, int len)
+{
+	int n, err;
+
+	err = make_umid();
+	if(err)
+		return err;
+
+	n = snprintf(buf, len, "%s%s/%s", uml_dir, umid, name);
+	if(n >= len){
+		printk("umid_file_name : buffer too short\n");
+		return -E2BIG;
+	}
+
+	return 0;
+}
+
+char *get_umid(void)
+{
+	return umid;
+}
+
+static int __init set_uml_dir(char *name, int *add)
+{
+	if(*name == '\0'){
+		printf("uml_dir can't be an empty string\n");
+		return 0;
+	}
+
+	if(name[strlen(name) - 1] == '/'){
+		uml_dir = name;
+		return 0;
+	}
+
+	uml_dir = malloc(strlen(name) + 2);
+	if(uml_dir == NULL){
+		printf("Failed to malloc uml_dir - error = %d\n", errno);
+
+		/* Return 0 here because do_initcalls doesn't look at
+		 * the return value.
+		 */
+		return 0;
+	}
+	sprintf(uml_dir, "%s/", name);
+
+	return 0;
+}
+
+__uml_setup("uml_dir=", set_uml_dir,
+"uml_dir=<directory>\n"
+"    The location to place the pid and umid files.\n\n"
+);
+
+static void remove_umid_dir(void)
+{
+	char dir[strlen(uml_dir) + UMID_LEN + 1], err;
+
+	sprintf(dir, "%s%s", uml_dir, umid);
+	err = remove_files_and_dir(dir);
+	if(err)
+		printf("remove_umid_dir - remove_files_and_dir failed with "
+		       "err = %d\n", err);
+}
+
+__uml_exitcall(remove_umid_dir);

arch/um/os-Linux/user_syms.c

@@ -0,0 +1,115 @@
+#include "linux/types.h"
+#include "linux/module.h"
+
+/* Some of this are builtin function (some are not but could in the future),
+ * so I *must* declare good prototypes for them and then EXPORT them.
+ * The kernel code uses the macro defined by include/linux/string.h,
+ * so I undef macros; the userspace code does not include that and I
+ * add an EXPORT for the glibc one.*/
+
+#undef strlen
+#undef strstr
+#undef memcpy
+#undef memset
+
+extern size_t strlen(const char *);
+extern void *memcpy(void *, const void *, size_t);
+extern void *memmove(void *, const void *, size_t);
+extern void *memset(void *, int, size_t);
+extern int printf(const char *, ...);
+
+/* If they're not defined, the export is included in lib/string.c.*/
+#ifdef __HAVE_ARCH_STRLEN
+EXPORT_SYMBOL(strlen);
+#endif
+#ifdef __HAVE_ARCH_STRSTR
+EXPORT_SYMBOL(strstr);
+#endif
+
+EXPORT_SYMBOL(memcpy);
+EXPORT_SYMBOL(memmove);
+EXPORT_SYMBOL(memset);
+EXPORT_SYMBOL(printf);
+
+/* Here, instead, I can provide a fake prototype. Yes, someone cares: genksyms.
+ * However, the modules will use the CRC defined *here*, no matter if it is
+ * good; so the versions of these symbols will always match
+ */
+#define EXPORT_SYMBOL_PROTO(sym)       \
+       int sym(void);                  \
+       EXPORT_SYMBOL(sym);
+
+extern void readdir64(void) __attribute__((weak));
+EXPORT_SYMBOL(readdir64);
+extern void truncate64(void) __attribute__((weak));
+EXPORT_SYMBOL(truncate64);
+
+#ifdef SUBARCH_i386
+EXPORT_SYMBOL(vsyscall_ehdr);
+EXPORT_SYMBOL(vsyscall_end);
+#endif
+
+EXPORT_SYMBOL_PROTO(__errno_location);
+
+EXPORT_SYMBOL_PROTO(access);
+EXPORT_SYMBOL_PROTO(open);
+EXPORT_SYMBOL_PROTO(open64);
+EXPORT_SYMBOL_PROTO(close);
+EXPORT_SYMBOL_PROTO(read);
+EXPORT_SYMBOL_PROTO(write);
+EXPORT_SYMBOL_PROTO(dup2);
+EXPORT_SYMBOL_PROTO(__xstat);
+EXPORT_SYMBOL_PROTO(__lxstat);
+EXPORT_SYMBOL_PROTO(__lxstat64);
+EXPORT_SYMBOL_PROTO(lseek);
+EXPORT_SYMBOL_PROTO(lseek64);
+EXPORT_SYMBOL_PROTO(chown);
+EXPORT_SYMBOL_PROTO(truncate);
+EXPORT_SYMBOL_PROTO(utime);
+EXPORT_SYMBOL_PROTO(chmod);
+EXPORT_SYMBOL_PROTO(rename);
+EXPORT_SYMBOL_PROTO(__xmknod);
+
+EXPORT_SYMBOL_PROTO(symlink);
+EXPORT_SYMBOL_PROTO(link);
+EXPORT_SYMBOL_PROTO(unlink);
+EXPORT_SYMBOL_PROTO(readlink);
+
+EXPORT_SYMBOL_PROTO(mkdir);
+EXPORT_SYMBOL_PROTO(rmdir);
+EXPORT_SYMBOL_PROTO(opendir);
+EXPORT_SYMBOL_PROTO(readdir);
+EXPORT_SYMBOL_PROTO(closedir);
+EXPORT_SYMBOL_PROTO(seekdir);
+EXPORT_SYMBOL_PROTO(telldir);
+
+EXPORT_SYMBOL_PROTO(ioctl);
+
+EXPORT_SYMBOL_PROTO(pread64);
+EXPORT_SYMBOL_PROTO(pwrite64);
+
+EXPORT_SYMBOL_PROTO(statfs);
+EXPORT_SYMBOL_PROTO(statfs64);
+
+EXPORT_SYMBOL_PROTO(getuid);
+
+EXPORT_SYMBOL_PROTO(fsync);
+EXPORT_SYMBOL_PROTO(fdatasync);
+
+/* Export symbols used by GCC for the stack protector. */
+extern void __stack_smash_handler(void *) __attribute__((weak));
+EXPORT_SYMBOL(__stack_smash_handler);
+
+extern long __guard __attribute__((weak));
+EXPORT_SYMBOL(__guard);
+
+/*
+ * Overrides for Emacs so that we follow Linus's tabbing style.
+ * Emacs will notice this stuff at the end of the file and automatically
+ * adjust the settings for this buffer only.  This must remain at the end
+ * of the file.
+ * ---------------------------------------------------------------------------
+ * Local variables:
+ * c-file-style: "linux"
+ * End:
+ */

arch/um/os-Linux/util.c

@@ -0,0 +1,123 @@
+/*
+ * Copyright (C) 2000, 2001, 2002 Jeff Dike (jdike@karaya.com)
+ * Licensed under the GPL
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <limits.h>
+#include <sys/mman.h>
+#include <sys/stat.h>
+#include <sys/utsname.h>
+#include <sys/param.h>
+#include <sys/time.h>
+#include "asm/types.h"
+#include <ctype.h>
+#include <signal.h>
+#include <wait.h>
+#include <errno.h>
+#include <stdarg.h>
+#include <sched.h>
+#include <termios.h>
+#include <string.h>
+#include "user_util.h"
+#include "kern_util.h"
+#include "user.h"
+#include "mem_user.h"
+#include "init.h"
+#include "ptrace_user.h"
+#include "uml-config.h"
+#include "os.h"
+#include "longjmp.h"
+
+void stack_protections(unsigned long address)
+{
+	int prot = PROT_READ | PROT_WRITE | PROT_EXEC;
+
+	if(mprotect((void *) address, page_size(), prot) < 0)
+		panic("protecting stack failed, errno = %d", errno);
+}
+
+void task_protections(unsigned long address)
+{
+	unsigned long guard = address + page_size();
+	unsigned long stack = guard + page_size();
+	int prot = 0, pages;
+
+#ifdef notdef
+	if(mprotect((void *) stack, page_size(), prot) < 0)
+		panic("protecting guard page failed, errno = %d", errno);
+#endif
+	pages = (1 << UML_CONFIG_KERNEL_STACK_ORDER) - 2;
+	prot = PROT_READ | PROT_WRITE | PROT_EXEC;
+	if(mprotect((void *) stack, pages * page_size(), prot) < 0)
+		panic("protecting stack failed, errno = %d", errno);
+}
+
+int raw(int fd)
+{
+	struct termios tt;
+	int err;
+
+	CATCH_EINTR(err = tcgetattr(fd, &tt));
+	if(err < 0)
+		return -errno;
+
+	cfmakeraw(&tt);
+
+	CATCH_EINTR(err = tcsetattr(fd, TCSADRAIN, &tt));
+	if(err < 0)
+		return -errno;
+
+	/* XXX tcsetattr could have applied only some changes
+	 * (and cfmakeraw() is a set of changes) */
+	return(0);
+}
+
+void setup_machinename(char *machine_out)
+{
+	struct utsname host;
+
+	uname(&host);
+#ifdef UML_CONFIG_UML_X86
+# ifndef UML_CONFIG_64BIT
+	if (!strcmp(host.machine, "x86_64")) {
+		strcpy(machine_out, "i686");
+		return;
+	}
+# else
+	if (!strcmp(host.machine, "i686")) {
+		strcpy(machine_out, "x86_64");
+		return;
+	}
+# endif
+#endif
+	strcpy(machine_out, host.machine);
+}
+
+char host_info[(_UTSNAME_LENGTH + 1) * 4 + _UTSNAME_NODENAME_LENGTH + 1];
+
+void setup_hostinfo(void)
+{
+	struct utsname host;
+
+	uname(&host);
+	sprintf(host_info, "%s %s %s %s %s", host.sysname, host.nodename,
+		host.release, host.version, host.machine);
+}
+
+int setjmp_wrapper(void (*proc)(void *, void *), ...)
+{
+	va_list args;
+	jmp_buf buf;
+	int n;
+
+	n = UML_SETJMP(&buf);
+	if(n == 0){
+		va_start(args, proc);
+		(*proc)(&buf, &args);
+	}
+	va_end(args);
+	return n;
+}