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| author | John Pittman <jpittman@redhat.com> | 2018-08-27 20:33:05 +0200 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2018-08-28 03:17:02 +0200 |
| commit | db193954ed9e35701b6e489fa4cc97b08589341b (patch) | |
| tree | 5ebcc8fb74104392763ba3a03eae0196f19ea6cd | |
| parent | block: remove unnecessary condition check (diff) | |
| download | linux-db193954ed9e35701b6e489fa4cc97b08589341b.tar.xz linux-db193954ed9e35701b6e489fa4cc97b08589341b.zip | |
block: bsg: move atomic_t ref_count variable to refcount API
Currently, variable ref_count within the bsg_device struct is of
type atomic_t. For variables being used as reference counters,
the refcount API should be used instead of atomic. The newer
refcount API works to prevent counter overflows and use-after-free
bugs. So, move this varable from the atomic API to refcount,
potentially avoiding the issues mentioned.
Signed-off-by: John Pittman <jpittman@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
| -rw-r--r-- | block/bsg.c | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/block/bsg.c b/block/bsg.c index db588add6ba6..9a442c23a715 100644 --- a/block/bsg.c +++ b/block/bsg.c @@ -37,7 +37,7 @@ struct bsg_device { struct request_queue *queue; spinlock_t lock; struct hlist_node dev_list; - atomic_t ref_count; + refcount_t ref_count; char name[20]; int max_queue; }; @@ -252,7 +252,7 @@ static int bsg_put_device(struct bsg_device *bd) mutex_lock(&bsg_mutex); - if (!atomic_dec_and_test(&bd->ref_count)) { + if (!refcount_dec_and_test(&bd->ref_count)) { mutex_unlock(&bsg_mutex); return 0; } @@ -290,7 +290,7 @@ static struct bsg_device *bsg_add_device(struct inode *inode, bd->queue = rq; - atomic_set(&bd->ref_count, 1); + refcount_set(&bd->ref_count, 1); hlist_add_head(&bd->dev_list, bsg_dev_idx_hash(iminor(inode))); strncpy(bd->name, dev_name(rq->bsg_dev.class_dev), sizeof(bd->name) - 1); @@ -308,7 +308,7 @@ static struct bsg_device *__bsg_get_device(int minor, struct request_queue *q) hlist_for_each_entry(bd, bsg_dev_idx_hash(minor), dev_list) { if (bd->queue == q) { - atomic_inc(&bd->ref_count); + refcount_inc(&bd->ref_count); goto found; } } |