bcache: Fix error handling in init code
This code appears to have rotted... fix various bugs and do some
refactoring.
Signed-off-by: Kent Overstreet <koverstreet@google.com>
diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
index b09beb2..f88e2b6 100644
--- a/drivers/md/bcache/super.c
+++ b/drivers/md/bcache/super.c
@@ -731,8 +731,7 @@
if (d->c)
bcache_device_detach(d);
-
- if (d->disk)
+ if (d->disk && d->disk->flags & GENHD_FL_UP)
del_gendisk(d->disk);
if (d->disk && d->disk->queue)
blk_cleanup_queue(d->disk->queue);
@@ -755,12 +754,9 @@
if (!(d->bio_split = bioset_create(4, offsetof(struct bbio, bio))) ||
!(d->unaligned_bvec = mempool_create_kmalloc_pool(1,
sizeof(struct bio_vec) * BIO_MAX_PAGES)) ||
- bio_split_pool_init(&d->bio_split_hook))
-
- return -ENOMEM;
-
- d->disk = alloc_disk(1);
- if (!d->disk)
+ bio_split_pool_init(&d->bio_split_hook) ||
+ !(d->disk = alloc_disk(1)) ||
+ !(q = blk_alloc_queue(GFP_KERNEL)))
return -ENOMEM;
snprintf(d->disk->disk_name, DISK_NAME_LEN, "bcache%i", bcache_minor);
@@ -770,10 +766,6 @@
d->disk->fops = &bcache_ops;
d->disk->private_data = d;
- q = blk_alloc_queue(GFP_KERNEL);
- if (!q)
- return -ENOMEM;
-
blk_queue_make_request(q, NULL);
d->disk->queue = q;
q->queuedata = d;
@@ -998,14 +990,17 @@
mutex_lock(&bch_register_lock);
- bd_unlink_disk_holder(dc->bdev, dc->disk.disk);
+ if (atomic_read(&dc->running))
+ bd_unlink_disk_holder(dc->bdev, dc->disk.disk);
bcache_device_free(&dc->disk);
list_del(&dc->list);
mutex_unlock(&bch_register_lock);
if (!IS_ERR_OR_NULL(dc->bdev)) {
- blk_sync_queue(bdev_get_queue(dc->bdev));
+ if (dc->bdev->bd_disk)
+ blk_sync_queue(bdev_get_queue(dc->bdev));
+
blkdev_put(dc->bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
}
@@ -1027,73 +1022,67 @@
static int cached_dev_init(struct cached_dev *dc, unsigned block_size)
{
- int err;
+ int ret;
struct io *io;
-
- closure_init(&dc->disk.cl, NULL);
- set_closure_fn(&dc->disk.cl, cached_dev_flush, system_wq);
+ struct request_queue *q = bdev_get_queue(dc->bdev);
__module_get(THIS_MODULE);
INIT_LIST_HEAD(&dc->list);
+ closure_init(&dc->disk.cl, NULL);
+ set_closure_fn(&dc->disk.cl, cached_dev_flush, system_wq);
kobject_init(&dc->disk.kobj, &bch_cached_dev_ktype);
-
- bch_cache_accounting_init(&dc->accounting, &dc->disk.cl);
-
- err = bcache_device_init(&dc->disk, block_size);
- if (err)
- goto err;
-
- spin_lock_init(&dc->io_lock);
- closure_init_unlocked(&dc->sb_write);
INIT_WORK(&dc->detach, cached_dev_detach_finish);
+ closure_init_unlocked(&dc->sb_write);
+ INIT_LIST_HEAD(&dc->io_lru);
+ spin_lock_init(&dc->io_lock);
+ bch_cache_accounting_init(&dc->accounting, &dc->disk.cl);
dc->sequential_merge = true;
dc->sequential_cutoff = 4 << 20;
- INIT_LIST_HEAD(&dc->io_lru);
- dc->sb_bio.bi_max_vecs = 1;
- dc->sb_bio.bi_io_vec = dc->sb_bio.bi_inline_vecs;
-
for (io = dc->io; io < dc->io + RECENT_IO; io++) {
list_add(&io->lru, &dc->io_lru);
hlist_add_head(&io->hash, dc->io_hash + RECENT_IO);
}
- bch_writeback_init_cached_dev(dc);
+ ret = bcache_device_init(&dc->disk, block_size);
+ if (ret)
+ return ret;
+
+ set_capacity(dc->disk.disk,
+ dc->bdev->bd_part->nr_sects - dc->sb.data_offset);
+
+ dc->disk.disk->queue->backing_dev_info.ra_pages =
+ max(dc->disk.disk->queue->backing_dev_info.ra_pages,
+ q->backing_dev_info.ra_pages);
+
+ bch_cached_dev_request_init(dc);
+ bch_cached_dev_writeback_init(dc);
return 0;
-err:
- bcache_device_stop(&dc->disk);
- return err;
}
/* Cached device - bcache superblock */
-static const char *register_bdev(struct cache_sb *sb, struct page *sb_page,
+static void register_bdev(struct cache_sb *sb, struct page *sb_page,
struct block_device *bdev,
struct cached_dev *dc)
{
char name[BDEVNAME_SIZE];
const char *err = "cannot allocate memory";
- struct gendisk *g;
struct cache_set *c;
- if (!dc || cached_dev_init(dc, sb->block_size << 9) != 0)
- return err;
-
memcpy(&dc->sb, sb, sizeof(struct cache_sb));
- dc->sb_bio.bi_io_vec[0].bv_page = sb_page;
dc->bdev = bdev;
dc->bdev->bd_holder = dc;
- g = dc->disk.disk;
+ bio_init(&dc->sb_bio);
+ dc->sb_bio.bi_max_vecs = 1;
+ dc->sb_bio.bi_io_vec = dc->sb_bio.bi_inline_vecs;
+ dc->sb_bio.bi_io_vec[0].bv_page = sb_page;
+ get_page(sb_page);
- set_capacity(g, dc->bdev->bd_part->nr_sects - dc->sb.data_offset);
-
- g->queue->backing_dev_info.ra_pages =
- max(g->queue->backing_dev_info.ra_pages,
- bdev->bd_queue->backing_dev_info.ra_pages);
-
- bch_cached_dev_request_init(dc);
+ if (cached_dev_init(dc, sb->block_size << 9))
+ goto err;
err = "error creating kobject";
if (kobject_add(&dc->disk.kobj, &part_to_dev(bdev->bd_part)->kobj,
@@ -1102,6 +1091,8 @@
if (bch_cache_accounting_add_kobjs(&dc->accounting, &dc->disk.kobj))
goto err;
+ pr_info("registered backing device %s", bdevname(bdev, name));
+
list_add(&dc->list, &uncached_devices);
list_for_each_entry(c, &bch_cache_sets, list)
bch_cached_dev_attach(dc, c);
@@ -1110,15 +1101,10 @@
BDEV_STATE(&dc->sb) == BDEV_STATE_STALE)
bch_cached_dev_run(dc);
- return NULL;
+ return;
err:
- kobject_put(&dc->disk.kobj);
pr_notice("error opening %s: %s", bdevname(bdev, name), err);
- /*
- * Return NULL instead of an error because kobject_put() cleans
- * everything up
- */
- return NULL;
+ bcache_device_stop(&dc->disk);
}
/* Flash only volumes */
@@ -1716,20 +1702,11 @@
size_t free;
struct bucket *b;
- if (!ca)
- return -ENOMEM;
-
__module_get(THIS_MODULE);
kobject_init(&ca->kobj, &bch_cache_ktype);
- memcpy(&ca->sb, sb, sizeof(struct cache_sb));
-
INIT_LIST_HEAD(&ca->discards);
- bio_init(&ca->sb_bio);
- ca->sb_bio.bi_max_vecs = 1;
- ca->sb_bio.bi_io_vec = ca->sb_bio.bi_inline_vecs;
-
bio_init(&ca->journal.bio);
ca->journal.bio.bi_max_vecs = 8;
ca->journal.bio.bi_io_vec = ca->journal.bio.bi_inline_vecs;
@@ -1741,18 +1718,17 @@
!init_fifo(&ca->free_inc, free << 2, GFP_KERNEL) ||
!init_fifo(&ca->unused, free << 2, GFP_KERNEL) ||
!init_heap(&ca->heap, free << 3, GFP_KERNEL) ||
- !(ca->buckets = vmalloc(sizeof(struct bucket) *
+ !(ca->buckets = vzalloc(sizeof(struct bucket) *
ca->sb.nbuckets)) ||
!(ca->prio_buckets = kzalloc(sizeof(uint64_t) * prio_buckets(ca) *
2, GFP_KERNEL)) ||
!(ca->disk_buckets = alloc_bucket_pages(GFP_KERNEL, ca)) ||
!(ca->alloc_workqueue = alloc_workqueue("bch_allocator", 0, 1)) ||
bio_split_pool_init(&ca->bio_split_hook))
- goto err;
+ return -ENOMEM;
ca->prio_last_buckets = ca->prio_buckets + prio_buckets(ca);
- memset(ca->buckets, 0, ca->sb.nbuckets * sizeof(struct bucket));
for_each_bucket(b, ca)
atomic_set(&b->pin, 0);
@@ -1765,22 +1741,28 @@
return -ENOMEM;
}
-static const char *register_cache(struct cache_sb *sb, struct page *sb_page,
+static void register_cache(struct cache_sb *sb, struct page *sb_page,
struct block_device *bdev, struct cache *ca)
{
char name[BDEVNAME_SIZE];
const char *err = "cannot allocate memory";
- if (cache_alloc(sb, ca) != 0)
- return err;
-
- ca->sb_bio.bi_io_vec[0].bv_page = sb_page;
+ memcpy(&ca->sb, sb, sizeof(struct cache_sb));
ca->bdev = bdev;
ca->bdev->bd_holder = ca;
+ bio_init(&ca->sb_bio);
+ ca->sb_bio.bi_max_vecs = 1;
+ ca->sb_bio.bi_io_vec = ca->sb_bio.bi_inline_vecs;
+ ca->sb_bio.bi_io_vec[0].bv_page = sb_page;
+ get_page(sb_page);
+
if (blk_queue_discard(bdev_get_queue(ca->bdev)))
ca->discard = CACHE_DISCARD(&ca->sb);
+ if (cache_alloc(sb, ca) != 0)
+ goto err;
+
err = "error creating kobject";
if (kobject_add(&ca->kobj, &part_to_dev(bdev->bd_part)->kobj, "bcache"))
goto err;
@@ -1790,15 +1772,10 @@
goto err;
pr_info("registered cache device %s", bdevname(bdev, name));
-
- return NULL;
+ return;
err:
+ pr_notice("error opening %s: %s", bdevname(bdev, name), err);
kobject_put(&ca->kobj);
- pr_info("error opening %s: %s", bdevname(bdev, name), err);
- /* Return NULL instead of an error because kobject_put() cleans
- * everything up
- */
- return NULL;
}
/* Global interfaces/init */
@@ -1832,12 +1809,15 @@
bdev = blkdev_get_by_path(strim(path),
FMODE_READ|FMODE_WRITE|FMODE_EXCL,
sb);
- if (bdev == ERR_PTR(-EBUSY))
- err = "device busy";
-
- if (IS_ERR(bdev) ||
- set_blocksize(bdev, 4096))
+ if (IS_ERR(bdev)) {
+ if (bdev == ERR_PTR(-EBUSY))
+ err = "device busy";
goto err;
+ }
+
+ err = "failed to set blocksize";
+ if (set_blocksize(bdev, 4096))
+ goto err_close;
err = read_super(sb, bdev, &sb_page);
if (err)
@@ -1845,33 +1825,33 @@
if (SB_IS_BDEV(sb)) {
struct cached_dev *dc = kzalloc(sizeof(*dc), GFP_KERNEL);
+ if (!dc)
+ goto err_close;
- err = register_bdev(sb, sb_page, bdev, dc);
+ register_bdev(sb, sb_page, bdev, dc);
} else {
struct cache *ca = kzalloc(sizeof(*ca), GFP_KERNEL);
+ if (!ca)
+ goto err_close;
- err = register_cache(sb, sb_page, bdev, ca);
+ register_cache(sb, sb_page, bdev, ca);
}
-
- if (err) {
- /* register_(bdev|cache) will only return an error if they
- * didn't get far enough to create the kobject - if they did,
- * the kobject destructor will do this cleanup.
- */
+out:
+ if (sb_page)
put_page(sb_page);
-err_close:
- blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
-err:
- if (attr != &ksysfs_register_quiet)
- pr_info("error opening %s: %s", path, err);
- ret = -EINVAL;
- }
-
kfree(sb);
kfree(path);
mutex_unlock(&bch_register_lock);
module_put(THIS_MODULE);
return ret;
+
+err_close:
+ blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
+err:
+ if (attr != &ksysfs_register_quiet)
+ pr_info("error opening %s: %s", path, err);
+ ret = -EINVAL;
+ goto out;
}
static int bcache_reboot(struct notifier_block *n, unsigned long code, void *x)