#define NR_RESERVED_BUFS 32
-static mdk_personality_t multipath_personality;
-static spinlock_t retry_list_lock = SPIN_LOCK_UNLOCKED;
-struct multipath_bh *multipath_retry_list = NULL, **multipath_retry_tail;
-
-
-static void *mp_pool_alloc(int gfp_flags, void *data)
-{
- struct multipath_bh *mpb;
- mpb = kmalloc(sizeof(*mpb), gfp_flags);
- if (mpb)
- memset(mpb, 0, sizeof(*mpb));
- return mpb;
-}
-
-static void mp_pool_free(void *mpb, void *data)
-{
- kfree(mpb);
-}
-
static int multipath_map (multipath_conf_t *conf)
{
int i, disks = conf->raid_disks;
* now we use the first available disk.
*/
- spin_lock_irq(&conf->device_lock);
+ rcu_read_lock();
for (i = 0; i < disks; i++) {
- mdk_rdev_t *rdev = conf->multipaths[i].rdev;
- if (rdev && rdev->in_sync) {
+ mdk_rdev_t *rdev = rcu_dereference(conf->multipaths[i].rdev);
+ if (rdev && test_bit(In_sync, &rdev->flags)) {
atomic_inc(&rdev->nr_pending);
- spin_unlock_irq(&conf->device_lock);
+ rcu_read_unlock();
return i;
}
}
- spin_unlock_irq(&conf->device_lock);
+ rcu_read_unlock();
printk(KERN_ERR "multipath_map(): no more operational IO paths?\n");
return (-1);
{
unsigned long flags;
mddev_t *mddev = mp_bh->mddev;
+ multipath_conf_t *conf = mddev_to_conf(mddev);
- spin_lock_irqsave(&retry_list_lock, flags);
- if (multipath_retry_list == NULL)
- multipath_retry_tail = &multipath_retry_list;
- *multipath_retry_tail = mp_bh;
- multipath_retry_tail = &mp_bh->next_mp;
- mp_bh->next_mp = NULL;
- spin_unlock_irqrestore(&retry_list_lock, flags);
+ spin_lock_irqsave(&conf->device_lock, flags);
+ list_add(&mp_bh->retry_list, &conf->retry_list);
+ spin_unlock_irqrestore(&conf->device_lock, flags);
md_wakeup_thread(mddev->thread);
}
mempool_free(mp_bh, conf->pool);
}
-int multipath_end_request(struct bio *bio, unsigned int bytes_done, int error)
+static int multipath_end_request(struct bio *bio, unsigned int bytes_done,
+ int error)
{
int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags);
struct multipath_bh * mp_bh = (struct multipath_bh *)(bio->bi_private);
{
multipath_conf_t *conf = mddev_to_conf(mddev);
int i;
- unsigned long flags;
- spin_lock_irqsave(&conf->device_lock, flags);
+ rcu_read_lock();
for (i=0; i<mddev->raid_disks; i++) {
- mdk_rdev_t *rdev = conf->multipaths[i].rdev;
- if (rdev && !rdev->faulty) {
+ mdk_rdev_t *rdev = rcu_dereference(conf->multipaths[i].rdev);
+ if (rdev && !test_bit(Faulty, &rdev->flags)
+ && atomic_read(&rdev->nr_pending)) {
request_queue_t *r_queue = bdev_get_queue(rdev->bdev);
atomic_inc(&rdev->nr_pending);
- spin_unlock_irqrestore(&conf->device_lock, flags);
+ rcu_read_unlock();
if (r_queue->unplug_fn)
r_queue->unplug_fn(r_queue);
- spin_lock_irqsave(&conf->device_lock, flags);
- atomic_dec(&rdev->nr_pending);
+ rdev_dec_pending(rdev, mddev);
+ rcu_read_lock();
}
}
- spin_unlock_irqrestore(&conf->device_lock, flags);
+ rcu_read_unlock();
}
+
static void multipath_unplug(request_queue_t *q)
{
unplug_slaves(q->queuedata);
multipath_conf_t *conf = mddev_to_conf(mddev);
struct multipath_bh * mp_bh;
struct multipath_info *multipath;
+ const int rw = bio_data_dir(bio);
+
+ if (unlikely(bio_barrier(bio))) {
+ bio_endio(bio, bio->bi_size, -EOPNOTSUPP);
+ return 0;
+ }
mp_bh = mempool_alloc(conf->pool, GFP_NOIO);
mp_bh->master_bio = bio;
mp_bh->mddev = mddev;
- if (bio_data_dir(bio)==WRITE) {
- disk_stat_inc(mddev->gendisk, writes);
- disk_stat_add(mddev->gendisk, write_sectors, bio_sectors(bio));
- } else {
- disk_stat_inc(mddev->gendisk, reads);
- disk_stat_add(mddev->gendisk, read_sectors, bio_sectors(bio));
- }
+ disk_stat_inc(mddev->gendisk, ios[rw]);
+ disk_stat_add(mddev->gendisk, sectors[rw], bio_sectors(bio));
mp_bh->path = multipath_map(conf);
if (mp_bh->path < 0) {
multipath = conf->multipaths + mp_bh->path;
mp_bh->bio = *bio;
+ mp_bh->bio.bi_sector += multipath->rdev->data_offset;
mp_bh->bio.bi_bdev = multipath->rdev->bdev;
mp_bh->bio.bi_rw |= (1 << BIO_RW_FAILFAST);
mp_bh->bio.bi_end_io = multipath_end_request;
for (i = 0; i < conf->raid_disks; i++)
seq_printf (seq, "%s",
conf->multipaths[i].rdev &&
- conf->multipaths[i].rdev->in_sync ? "U" : "_");
+ test_bit(In_sync, &conf->multipaths[i].rdev->flags) ? "U" : "_");
seq_printf (seq, "]");
}
multipath_conf_t *conf = mddev_to_conf(mddev);
int i, ret = 0;
- for (i=0; i<mddev->raid_disks; i++) {
- mdk_rdev_t *rdev = conf->multipaths[i].rdev;
- if (rdev && !rdev->faulty) {
+ rcu_read_lock();
+ for (i=0; i<mddev->raid_disks && ret == 0; i++) {
+ mdk_rdev_t *rdev = rcu_dereference(conf->multipaths[i].rdev);
+ if (rdev && !test_bit(Faulty, &rdev->flags)) {
struct block_device *bdev = rdev->bdev;
request_queue_t *r_queue = bdev_get_queue(bdev);
- if (!r_queue->issue_flush_fn) {
+ if (!r_queue->issue_flush_fn)
ret = -EOPNOTSUPP;
- break;
+ else {
+ atomic_inc(&rdev->nr_pending);
+ rcu_read_unlock();
+ ret = r_queue->issue_flush_fn(r_queue, bdev->bd_disk,
+ error_sector);
+ rdev_dec_pending(rdev, mddev);
+ rcu_read_lock();
}
+ }
+ }
+ rcu_read_unlock();
+ return ret;
+}
+static int multipath_congested(void *data, int bits)
+{
+ mddev_t *mddev = data;
+ multipath_conf_t *conf = mddev_to_conf(mddev);
+ int i, ret = 0;
+
+ rcu_read_lock();
+ for (i = 0; i < mddev->raid_disks ; i++) {
+ mdk_rdev_t *rdev = rcu_dereference(conf->multipaths[i].rdev);
+ if (rdev && !test_bit(Faulty, &rdev->flags)) {
+ request_queue_t *q = bdev_get_queue(rdev->bdev);
- ret = r_queue->issue_flush_fn(r_queue, bdev->bd_disk, error_sector);
- if (ret)
- break;
+ ret |= bdi_congested(&q->backing_dev_info, bits);
+ /* Just like multipath_map, we just check the
+ * first available device
+ */
+ break;
}
}
+ rcu_read_unlock();
return ret;
}
/*
* Mark disk as unusable
*/
- if (!rdev->faulty) {
+ if (!test_bit(Faulty, &rdev->flags)) {
char b[BDEVNAME_SIZE];
- rdev->in_sync = 0;
- rdev->faulty = 1;
- mddev->sb_dirty = 1;
+ clear_bit(In_sync, &rdev->flags);
+ set_bit(Faulty, &rdev->flags);
+ set_bit(MD_CHANGE_DEVS, &mddev->flags);
conf->working_disks--;
+ mddev->degraded++;
printk(KERN_ALERT "multipath: IO failure on %s,"
" disabling IO path. \n Operation continuing"
" on %d IO paths.\n",
tmp = conf->multipaths + i;
if (tmp->rdev)
printk(" disk%d, o:%d, dev:%s\n",
- i,!tmp->rdev->faulty,
+ i,!test_bit(Faulty, &tmp->rdev->flags),
bdevname(tmp->rdev->bdev,b));
}
}
static int multipath_add_disk(mddev_t *mddev, mdk_rdev_t *rdev)
{
multipath_conf_t *conf = mddev->private;
+ struct request_queue *q;
int found = 0;
int path;
struct multipath_info *p;
print_multipath_conf(conf);
- spin_lock_irq(&conf->device_lock);
+
for (path=0; path<mddev->raid_disks; path++)
if ((p=conf->multipaths+path)->rdev == NULL) {
- p->rdev = rdev;
- blk_queue_stack_limits(mddev->queue,
- rdev->bdev->bd_disk->queue);
+ q = rdev->bdev->bd_disk->queue;
+ blk_queue_stack_limits(mddev->queue, q);
/* as we don't honour merge_bvec_fn, we must never risk
* violating it, so limit ->max_sector to one PAGE, as
* (Note: it is very unlikely that a device with
* merge_bvec_fn will be involved in multipath.)
*/
- if (rdev->bdev->bd_disk->queue->merge_bvec_fn &&
+ if (q->merge_bvec_fn &&
mddev->queue->max_sectors > (PAGE_SIZE>>9))
blk_queue_max_sectors(mddev->queue, PAGE_SIZE>>9);
conf->working_disks++;
+ mddev->degraded--;
rdev->raid_disk = path;
- rdev->in_sync = 1;
+ set_bit(In_sync, &rdev->flags);
+ rcu_assign_pointer(p->rdev, rdev);
found = 1;
}
- spin_unlock_irq(&conf->device_lock);
print_multipath_conf(conf);
return found;
static int multipath_remove_disk(mddev_t *mddev, int number)
{
multipath_conf_t *conf = mddev->private;
- int err = 1;
+ int err = 0;
+ mdk_rdev_t *rdev;
struct multipath_info *p = conf->multipaths + number;
print_multipath_conf(conf);
- spin_lock_irq(&conf->device_lock);
- if (p->rdev) {
- if (p->rdev->in_sync ||
- atomic_read(&p->rdev->nr_pending)) {
+ rdev = p->rdev;
+ if (rdev) {
+ if (test_bit(In_sync, &rdev->flags) ||
+ atomic_read(&rdev->nr_pending)) {
printk(KERN_ERR "hot-remove-disk, slot %d is identified" " but is still operational!\n", number);
err = -EBUSY;
goto abort;
}
p->rdev = NULL;
- err = 0;
+ synchronize_rcu();
+ if (atomic_read(&rdev->nr_pending)) {
+ /* lost the race, try later */
+ err = -EBUSY;
+ p->rdev = rdev;
+ }
}
- if (err)
- MD_BUG();
abort:
- spin_unlock_irq(&conf->device_lock);
print_multipath_conf(conf);
return err;
struct bio *bio;
unsigned long flags;
multipath_conf_t *conf = mddev_to_conf(mddev);
+ struct list_head *head = &conf->retry_list;
md_check_recovery(mddev);
for (;;) {
char b[BDEVNAME_SIZE];
- spin_lock_irqsave(&retry_list_lock, flags);
- mp_bh = multipath_retry_list;
- if (!mp_bh)
+ spin_lock_irqsave(&conf->device_lock, flags);
+ if (list_empty(head))
break;
- multipath_retry_list = mp_bh->next_mp;
- spin_unlock_irqrestore(&retry_list_lock, flags);
+ mp_bh = list_entry(head->prev, struct multipath_bh, retry_list);
+ list_del(head->prev);
+ spin_unlock_irqrestore(&conf->device_lock, flags);
- mddev = mp_bh->mddev;
bio = &mp_bh->bio;
bio->bi_sector = mp_bh->master_bio->bi_sector;
bdevname(bio->bi_bdev,b),
(unsigned long long)bio->bi_sector);
*bio = *(mp_bh->master_bio);
+ bio->bi_sector += conf->multipaths[mp_bh->path].rdev->data_offset;
bio->bi_bdev = conf->multipaths[mp_bh->path].rdev->bdev;
bio->bi_rw |= (1 << BIO_RW_FAILFAST);
bio->bi_end_io = multipath_end_request;
generic_make_request(bio);
}
}
- spin_unlock_irqrestore(&retry_list_lock, flags);
+ spin_unlock_irqrestore(&conf->device_lock, flags);
}
static int multipath_run (mddev_t *mddev)
* should be freed in multipath_stop()]
*/
- conf = kmalloc(sizeof(multipath_conf_t), GFP_KERNEL);
+ conf = kzalloc(sizeof(multipath_conf_t), GFP_KERNEL);
mddev->private = conf;
if (!conf) {
printk(KERN_ERR
mdname(mddev));
goto out;
}
- memset(conf, 0, sizeof(*conf));
- conf->multipaths = kmalloc(sizeof(struct multipath_info)*mddev->raid_disks,
+ conf->multipaths = kzalloc(sizeof(struct multipath_info)*mddev->raid_disks,
GFP_KERNEL);
if (!conf->multipaths) {
printk(KERN_ERR
mdname(mddev));
goto out_free_conf;
}
- memset(conf->multipaths, 0, sizeof(struct multipath_info)*mddev->raid_disks);
-
- mddev->queue->unplug_fn = multipath_unplug;
-
- mddev->queue->issue_flush_fn = multipath_issue_flush;
conf->working_disks = 0;
ITERATE_RDEV(mddev,rdev,tmp) {
mddev->queue->max_sectors > (PAGE_SIZE>>9))
blk_queue_max_sectors(mddev->queue, PAGE_SIZE>>9);
- if (!rdev->faulty)
+ if (!test_bit(Faulty, &rdev->flags))
conf->working_disks++;
}
conf->raid_disks = mddev->raid_disks;
- mddev->sb_dirty = 1;
conf->mddev = mddev;
- conf->device_lock = SPIN_LOCK_UNLOCKED;
+ spin_lock_init(&conf->device_lock);
+ INIT_LIST_HEAD(&conf->retry_list);
if (!conf->working_disks) {
printk(KERN_ERR "multipath: no operational IO paths for %s\n",
mdname(mddev));
goto out_free_conf;
}
- mddev->degraded = conf->raid_disks = conf->working_disks;
+ mddev->degraded = conf->raid_disks - conf->working_disks;
- conf->pool = mempool_create(NR_RESERVED_BUFS,
- mp_pool_alloc, mp_pool_free,
- NULL);
+ conf->pool = mempool_create_kzalloc_pool(NR_RESERVED_BUFS,
+ sizeof(struct multipath_bh));
if (conf->pool == NULL) {
printk(KERN_ERR
"multipath: couldn't allocate memory for %s\n",
* Ok, everything is just fine now
*/
mddev->array_size = mddev->size;
+
+ mddev->queue->unplug_fn = multipath_unplug;
+ mddev->queue->issue_flush_fn = multipath_issue_flush;
+ mddev->queue->backing_dev_info.congested_fn = multipath_congested;
+ mddev->queue->backing_dev_info.congested_data = mddev;
+
return 0;
out_free_conf:
if (conf->pool)
mempool_destroy(conf->pool);
- if (conf->multipaths)
- kfree(conf->multipaths);
+ kfree(conf->multipaths);
kfree(conf);
mddev->private = NULL;
out:
md_unregister_thread(mddev->thread);
mddev->thread = NULL;
+ blk_sync_queue(mddev->queue); /* the unplug fn references 'conf'*/
mempool_destroy(conf->pool);
kfree(conf->multipaths);
kfree(conf);
return 0;
}
-static mdk_personality_t multipath_personality=
+static struct mdk_personality multipath_personality =
{
.name = "multipath",
+ .level = LEVEL_MULTIPATH,
.owner = THIS_MODULE,
.make_request = multipath_make_request,
.run = multipath_run,
static int __init multipath_init (void)
{
- return register_md_personality (MULTIPATH, &multipath_personality);
+ return register_md_personality (&multipath_personality);
}
static void __exit multipath_exit (void)
{
- unregister_md_personality (MULTIPATH);
+ unregister_md_personality (&multipath_personality);
}
module_init(multipath_init);
module_exit(multipath_exit);
MODULE_LICENSE("GPL");
MODULE_ALIAS("md-personality-7"); /* MULTIPATH */
+MODULE_ALIAS("md-multipath");
+MODULE_ALIAS("md-level--4");
git://git.onelab.eu / linux-2.6.git / blobdiff