Creation of Cybook 2416 (actually Gen4) repository

drivers/block/aoe/aoedev.c

@@ -0,0 +1,220 @@
+/* Copyright (c) 2006 Coraid, Inc.  See COPYING for GPL terms. */
+/*
+ * aoedev.c
+ * AoE device utility functions; maintains device list.
+ */
+
+#include <linux/hdreg.h>
+#include <linux/blkdev.h>
+#include <linux/netdevice.h>
+#include "aoe.h"
+
+static struct aoedev *devlist;
+static spinlock_t devlist_lock;
+
+int
+aoedev_isbusy(struct aoedev *d)
+{
+	struct frame *f, *e;
+
+	f = d->frames;
+	e = f + d->nframes;
+	do {
+		if (f->tag != FREETAG)
+			return 1;
+	} while (++f < e);
+
+	return 0;
+}
+
+struct aoedev *
+aoedev_by_aoeaddr(int maj, int min)
+{
+	struct aoedev *d;
+	ulong flags;
+
+	spin_lock_irqsave(&devlist_lock, flags);
+
+	for (d=devlist; d; d=d->next)
+		if (d->aoemajor == maj && d->aoeminor == min)
+			break;
+
+	spin_unlock_irqrestore(&devlist_lock, flags);
+	return d;
+}
+
+static void
+dummy_timer(ulong vp)
+{
+	struct aoedev *d;
+
+	d = (struct aoedev *)vp;
+	if (d->flags & DEVFL_TKILL)
+		return;
+	d->timer.expires = jiffies + HZ;
+	add_timer(&d->timer);
+}
+
+/* called with devlist lock held */
+static struct aoedev *
+aoedev_newdev(ulong nframes)
+{
+	struct aoedev *d;
+	struct frame *f, *e;
+
+	d = kzalloc(sizeof *d, GFP_ATOMIC);
+	f = kcalloc(nframes, sizeof *f, GFP_ATOMIC);
+ 	switch (!d || !f) {
+ 	case 0:
+ 		d->nframes = nframes;
+ 		d->frames = f;
+ 		e = f + nframes;
+ 		for (; f<e; f++) {
+ 			f->tag = FREETAG;
+ 			f->skb = new_skb(ETH_ZLEN);
+ 			if (!f->skb)
+ 				break;
+ 		}
+ 		if (f == e)
+ 			break;
+ 		while (f > d->frames) {
+ 			f--;
+ 			dev_kfree_skb(f->skb);
+ 		}
+ 	default:
+ 		if (f)
+ 			kfree(f);
+ 		if (d)
+ 			kfree(d);
+		return NULL;
+	}
+	INIT_WORK(&d->work, aoecmd_sleepwork);
+	spin_lock_init(&d->lock);
+	init_timer(&d->timer);
+	d->timer.data = (ulong) d;
+	d->timer.function = dummy_timer;
+	d->timer.expires = jiffies + HZ;
+	add_timer(&d->timer);
+	d->bufpool = NULL;	/* defer to aoeblk_gdalloc */
+	INIT_LIST_HEAD(&d->bufq);
+	d->next = devlist;
+	devlist = d;
+
+	return d;
+}
+
+void
+aoedev_downdev(struct aoedev *d)
+{
+	struct frame *f, *e;
+	struct buf *buf;
+	struct bio *bio;
+
+	f = d->frames;
+	e = f + d->nframes;
+	for (; f<e; f->tag = FREETAG, f->buf = NULL, f++) {
+		if (f->tag == FREETAG || f->buf == NULL)
+			continue;
+		buf = f->buf;
+		bio = buf->bio;
+		if (--buf->nframesout == 0) {
+			mempool_free(buf, d->bufpool);
+			bio_endio(bio, bio->bi_size, -EIO);
+		}
+		skb_shinfo(f->skb)->nr_frags = f->skb->data_len = 0;
+	}
+	d->inprocess = NULL;
+
+	while (!list_empty(&d->bufq)) {
+		buf = container_of(d->bufq.next, struct buf, bufs);
+		list_del(d->bufq.next);
+		bio = buf->bio;
+		mempool_free(buf, d->bufpool);
+		bio_endio(bio, bio->bi_size, -EIO);
+	}
+
+	if (d->gd)
+		d->gd->capacity = 0;
+
+	d->flags &= ~(DEVFL_UP | DEVFL_PAUSE);
+}
+
+/* find it or malloc it */
+struct aoedev *
+aoedev_by_sysminor_m(ulong sysminor, ulong bufcnt)
+{
+	struct aoedev *d;
+	ulong flags;
+
+	spin_lock_irqsave(&devlist_lock, flags);
+
+	for (d=devlist; d; d=d->next)
+		if (d->sysminor == sysminor)
+			break;
+
+	if (d == NULL) {
+		d = aoedev_newdev(bufcnt);
+	 	if (d == NULL) {
+			spin_unlock_irqrestore(&devlist_lock, flags);
+			printk(KERN_INFO "aoe: aoedev_newdev failure.\n");
+			return NULL;
+		}
+		d->sysminor = sysminor;
+		d->aoemajor = AOEMAJOR(sysminor);
+		d->aoeminor = AOEMINOR(sysminor);
+	}
+
+	spin_unlock_irqrestore(&devlist_lock, flags);
+	return d;
+}
+
+static void
+aoedev_freedev(struct aoedev *d)
+{
+	struct frame *f, *e;
+
+	if (d->gd) {
+		aoedisk_rm_sysfs(d);
+		del_gendisk(d->gd);
+		put_disk(d->gd);
+	}
+	f = d->frames;
+	e = f + d->nframes;
+	for (; f<e; f++) {
+		skb_shinfo(f->skb)->nr_frags = 0;
+		dev_kfree_skb(f->skb);
+	}
+	kfree(d->frames);
+	if (d->bufpool)
+		mempool_destroy(d->bufpool);
+	kfree(d);
+}
+
+void
+aoedev_exit(void)
+{
+	struct aoedev *d;
+	ulong flags;
+
+	flush_scheduled_work();
+
+	while ((d = devlist)) {
+		devlist = d->next;
+
+		spin_lock_irqsave(&d->lock, flags);
+		aoedev_downdev(d);
+		d->flags |= DEVFL_TKILL;
+		spin_unlock_irqrestore(&d->lock, flags);
+
+		del_timer_sync(&d->timer);
+		aoedev_freedev(d);
+	}
+}
+
+int __init
+aoedev_init(void)
+{
+	spin_lock_init(&devlist_lock);
+	return 0;
+}
+