diff options
Diffstat (limited to 'fs/block_dev.c')
-rw-r--r-- | fs/block_dev.c | 58 |
1 files changed, 40 insertions, 18 deletions
diff --git a/fs/block_dev.c b/fs/block_dev.c index bc8f27cc4483..36c0e7af9d0f 100644 --- a/fs/block_dev.c +++ b/fs/block_dev.c @@ -642,34 +642,47 @@ static void free_bd_holder(struct bd_holder *bo) } /** + * find_bd_holder - find matching struct bd_holder from the block device + * + * @bdev: struct block device to be searched + * @bo: target struct bd_holder + * + * Returns matching entry with @bo in @bdev->bd_holder_list. + * If found, increment the reference count and return the pointer. + * If not found, returns NULL. + */ +static struct bd_holder *find_bd_holder(struct block_device *bdev, + struct bd_holder *bo) +{ + struct bd_holder *tmp; + + list_for_each_entry(tmp, &bdev->bd_holder_list, list) + if (tmp->sdir == bo->sdir) { + tmp->count++; + return tmp; + } + + return NULL; +} + +/** * add_bd_holder - create sysfs symlinks for bd_claim() relationship * * @bdev: block device to be bd_claimed * @bo: preallocated and initialized by alloc_bd_holder() * - * If there is no matching entry with @bo in @bdev->bd_holder_list, - * add @bo to the list, create symlinks. + * Add @bo to @bdev->bd_holder_list, create symlinks. * - * Returns 0 if symlinks are created or already there. - * Returns -ve if something fails and @bo can be freed. + * Returns 0 if symlinks are created. + * Returns -ve if something fails. */ static int add_bd_holder(struct block_device *bdev, struct bd_holder *bo) { - struct bd_holder *tmp; int ret; if (!bo) return -EINVAL; - list_for_each_entry(tmp, &bdev->bd_holder_list, list) { - if (tmp->sdir == bo->sdir) { - tmp->count++; - /* We've already done what we need to do here. */ - free_bd_holder(bo); - return 0; - } - } - if (!bd_holder_grab_dirs(bdev, bo)) return -EBUSY; @@ -740,7 +753,7 @@ static int bd_claim_by_kobject(struct block_device *bdev, void *holder, struct kobject *kobj) { int res; - struct bd_holder *bo; + struct bd_holder *bo, *found; if (!kobj) return -EINVAL; @@ -751,9 +764,16 @@ static int bd_claim_by_kobject(struct block_device *bdev, void *holder, mutex_lock_nested(&bdev->bd_mutex, BD_MUTEX_PARTITION); res = bd_claim(bdev, holder); - if (res == 0) - res = add_bd_holder(bdev, bo); - if (res) + if (res == 0) { + found = find_bd_holder(bdev, bo); + if (found == NULL) { + res = add_bd_holder(bdev, bo); + if (res) + bd_release(bdev); + } + } + + if (res || found) free_bd_holder(bo); mutex_unlock(&bdev->bd_mutex); @@ -1131,6 +1151,8 @@ static int blkdev_open(struct inode * inode, struct file * filp) filp->f_flags |= O_LARGEFILE; bdev = bd_acquire(inode); + if (bdev == NULL) + return -ENOMEM; res = do_open(bdev, filp, BD_MUTEX_NORMAL); if (res) |