aoeblk.c
/* Copyright (c) 2007 Coraid, Inc. See COPYING for GPL terms. */
/*
* aoeblk.c
* block device routines
*/
#include <linux/hdreg.h>
#include <linux/blkdev.h>
#include <linux/backing-dev.h>
#include <linux/fs.h>
#include <linux/ioctl.h>
#include <linux/genhd.h>
#include <linux/netdevice.h>
#include "aoe.h"
static struct kmem_cache *buf_pool_cache;
static ssize_t aoedisk_show_state(struct device *dev,
struct device_attribute *attr, char *page)
{
struct gendisk *disk = dev_to_disk(dev);
struct aoedev *d = disk->private_data;
return snprintf(page, PAGE_SIZE,
"%s%s\n",
(d->flags & DEVFL_UP) ? "up" : "down",
(d->flags & DEVFL_KICKME) ? ",kickme" :
(d->nopen && !(d->flags & DEVFL_UP)) ? ",closewait" : "");
/* I'd rather see nopen exported so we can ditch closewait */
}
static ssize_t aoedisk_show_mac(struct device *dev,
struct device_attribute *attr, char *page)
{
struct gendisk *disk = dev_to_disk(dev);
struct aoedev *d = disk->private_data;
struct aoetgt *t = d->targets[0];
if (t == NULL)
return snprintf(page, PAGE_SIZE, "none\n");
return snprintf(page, PAGE_SIZE, "%pm\n", t->addr);
}
static ssize_t aoedisk_show_netif(struct device *dev,
struct device_attribute *attr, char *page)
{
struct gendisk *disk = dev_to_disk(dev);
struct aoedev *d = disk->private_data;
struct net_device *nds[8], **nd, **nnd, **ne;
struct aoetgt **t, **te;
struct aoeif *ifp, *e;
char *p;
memset(nds, 0, sizeof nds);
nd = nds;
ne = nd + ARRAY_SIZE(nds);
t = d->targets;
te = t + NTARGETS;
for (; t < te && *t; t++) {
ifp = (*t)->ifs;
e = ifp + NAOEIFS;
for (; ifp < e && ifp->nd; ifp++) {
for (nnd = nds; nnd < nd; nnd++)
if (*nnd == ifp->nd)
break;
if (nnd == nd && nd != ne)
*nd++ = ifp->nd;
}
}
ne = nd;
nd = nds;
if (*nd == NULL)
return snprintf(page, PAGE_SIZE, "none\n");
for (p = page; nd < ne; nd++)
p += snprintf(p, PAGE_SIZE - (p-page), "%s%s",
p == page ? "" : ",", (*nd)->name);
p += snprintf(p, PAGE_SIZE - (p-page), "\n");
return p-page;
}
/* firmware version */
static ssize_t aoedisk_show_fwver(struct device *dev,
struct device_attribute *attr, char *page)
{
struct gendisk *disk = dev_to_disk(dev);
struct aoedev *d = disk->private_data;
return snprintf(page, PAGE_SIZE, "0x%04x\n", (unsigned int) d->fw_ver);
}
static DEVICE_ATTR(state, S_IRUGO, aoedisk_show_state, NULL);
static DEVICE_ATTR(mac, S_IRUGO, aoedisk_show_mac, NULL);
static DEVICE_ATTR(netif, S_IRUGO, aoedisk_show_netif, NULL);
static struct device_attribute dev_attr_firmware_version = {
.attr = { .name = "firmware-version", .mode = S_IRUGO },
.show = aoedisk_show_fwver,
};
static struct attribute *aoe_attrs[] = {
&dev_attr_state.attr,
&dev_attr_mac.attr,
&dev_attr_netif.attr,
&dev_attr_firmware_version.attr,
NULL,
};
static const struct attribute_group attr_group = {
.attrs = aoe_attrs,
};
static int
aoedisk_add_sysfs(struct aoedev *d)
{
return sysfs_create_group(&disk_to_dev(d->gd)->kobj, &attr_group);
}
void
aoedisk_rm_sysfs(struct aoedev *d)
{
sysfs_remove_group(&disk_to_dev(d->gd)->kobj, &attr_group);
}
static int
aoeblk_open(struct block_device *bdev, fmode_t mode)
{
struct aoedev *d = bdev->bd_disk->private_data;
ulong flags;
spin_lock_irqsave(&d->lock, flags);
if (d->flags & DEVFL_UP) {
d->nopen++;
spin_unlock_irqrestore(&d->lock, flags);
return 0;
}
spin_unlock_irqrestore(&d->lock, flags);
return -ENODEV;
}
static int
aoeblk_release(struct gendisk *disk, fmode_t mode)
{
struct aoedev *d = disk->private_data;
ulong flags;
spin_lock_irqsave(&d->lock, flags);
if (--d->nopen == 0) {
spin_unlock_irqrestore(&d->lock, flags);
aoecmd_cfg(d->aoemajor, d->aoeminor);
return 0;
}
spin_unlock_irqrestore(&d->lock, flags);
return 0;
}
static int
aoeblk_make_request(struct request_queue *q, struct bio *bio)
{
struct sk_buff_head queue;
struct aoedev *d;
struct buf *buf;
ulong flags;
blk_queue_bounce(q, &bio);
if (bio == NULL) {
printk(KERN_ERR "aoe: bio is NULL\n");
BUG();
return 0;
}
d = bio->bi_bdev->bd_disk->private_data;
if (d == NULL) {
printk(KERN_ERR "aoe: bd_disk->private_data is NULL\n");
BUG();
bio_endio(bio, -ENXIO);
return 0;
} else if (bio_rw_flagged(bio, BIO_RW_BARRIER)) {
bio_endio(bio, -EOPNOTSUPP);
return 0;
} else if (bio->bi_io_vec == NULL) {
printk(KERN_ERR "aoe: bi_io_vec is NULL\n");
BUG();
bio_endio(bio, -ENXIO);
return 0;
}
buf = mempool_alloc(d->bufpool, GFP_NOIO);
if (buf == NULL) {
printk(KERN_INFO "aoe: buf allocation failure\n");
bio_endio(bio, -ENOMEM);
return 0;
}
memset(buf, 0, sizeof(*buf));
INIT_LIST_HEAD(&buf->bufs);
buf->stime = jiffies;
buf->bio = bio;
buf->resid = bio->bi_size;
buf->sector = bio->bi_sector;
buf->bv = &bio->bi_io_vec[bio->bi_idx];
buf->bv_resid = buf->bv->bv_len;
WARN_ON(buf->bv_resid == 0);
buf->bv_off = buf->bv->bv_offset;
spin_lock_irqsave(&d->lock, flags);
if ((d->flags & DEVFL_UP) == 0) {
printk(KERN_INFO "aoe: device %ld.%d is not up\n",
d->aoemajor, d->aoeminor);
spin_unlock_irqrestore(&d->lock, flags);
mempool_free(buf, d->bufpool);
bio_endio(bio, -ENXIO);
return 0;
}
list_add_tail(&buf->bufs, &d->bufq);
aoecmd_work(d);
__skb_queue_head_init(&queue);
skb_queue_splice_init(&d->sendq, &queue);
spin_unlock_irqrestore(&d->lock, flags);
aoenet_xmit(&queue);
return 0;
}
static int
aoeblk_getgeo(struct block_device *bdev, struct hd_geometry *geo)
{
struct aoedev *d = bdev->bd_disk->private_data;
if ((d->flags & DEVFL_UP) == 0) {
printk(KERN_ERR "aoe: disk not up\n");
return -ENODEV;
}
geo->cylinders = d->geo.cylinders;
geo->heads = d->geo.heads;
geo->sectors = d->geo.sectors;
return 0;
}
static const struct block_device_operations aoe_bdops = {
.open = aoeblk_open,
.release = aoeblk_release,
.getgeo = aoeblk_getgeo,
.owner = THIS_MODULE,
};
/* alloc_disk and add_disk can sleep */
void
aoeblk_gdalloc(void *vp)
{
struct aoedev *d = vp;
struct gendisk *gd;
ulong flags;
gd = alloc_disk(AOE_PARTITIONS);
if (gd == NULL) {
printk(KERN_ERR
"aoe: cannot allocate disk structure for %ld.%d\n",
d->aoemajor, d->aoeminor);
goto err;
}
d->bufpool = mempool_create_slab_pool(MIN_BUFS, buf_pool_cache);
if (d->bufpool == NULL) {
printk(KERN_ERR "aoe: cannot allocate bufpool for %ld.%d\n",
d->aoemajor, d->aoeminor);
goto err_disk;
}
d->blkq = blk_alloc_queue(GFP_KERNEL);
if (!d->blkq)
goto err_mempool;
blk_queue_make_request(d->blkq, aoeblk_make_request);
d->blkq->backing_dev_info.name = "aoe";
if (bdi_init(&d->blkq->backing_dev_info))
goto err_blkq;
spin_lock_irqsave(&d->lock, flags);
gd->major = AOE_MAJOR;
gd->first_minor = d->sysminor * AOE_PARTITIONS;
gd->fops = &aoe_bdops;
gd->private_data = d;
set_capacity(gd, d->ssize);
snprintf(gd->disk_name, sizeof gd->disk_name, "etherd/e%ld.%d",
d->aoemajor, d->aoeminor);
gd->queue = d->blkq;
d->gd = gd;
d->flags &= ~DEVFL_GDALLOC;
d->flags |= DEVFL_UP;
spin_unlock_irqrestore(&d->lock, flags);
add_disk(gd);
aoedisk_add_sysfs(d);
return;
err_blkq:
blk_cleanup_queue(d->blkq);
d->blkq = NULL;
err_mempool:
mempool_destroy(d->bufpool);
err_disk:
put_disk(gd);
err:
spin_lock_irqsave(&d->lock, flags);
d->flags &= ~DEVFL_GDALLOC;
spin_unlock_irqrestore(&d->lock, flags);
}
void
aoeblk_exit(void)
{
kmem_cache_destroy(buf_pool_cache);
}
int __init
aoeblk_init(void)
{
buf_pool_cache = kmem_cache_create("aoe_bufs",
sizeof(struct buf),
0, 0, NULL);
if (buf_pool_cache == NULL)
return -ENOMEM;
return 0;
}