diff options
| author | Tejun Heo <tj@kernel.org> | 2010-11-13 11:55:16 +0100 |
|---|---|---|
| committer | Tejun Heo <tj@kernel.org> | 2010-11-13 11:55:16 +0100 |
| commit | 731edacb7567c15f25b1fccac18a203bd432ae5e (patch) | |
| tree | 0ad6f16b306847e7626cea84c684ea4a044233da /drivers/mtd/devices | |
| parent | f6614b7bb405a9b35dd28baea989a749492c46b2 (diff) | |
| download | linux-next-731edacb7567c15f25b1fccac18a203bd432ae5e.tar.gz | |
mtd: fix bdev exclusive open bugs in block2mtd::add_device()
There are two bdev exclusive open bugs.
* open_bdev_exclusive() must not be called with NULL holder. Use dev
as the holder.
* open_by_devnum() doesn't open the bdev exclusively but
block2mtd_free_device() always assumes it. Explicitly claim the
bdev.
The latter is rather clumsy but will be simplified with future
blkdev_get/put() cleanups.
- Updated to use local variable @mode to cache FMODE_* masks as
suggested by Artem Bityutskiy.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: linux-mtd@lists.infradead.org
Cc: Artem Bityutskiy <dedekind1@gmail.com>
Diffstat (limited to 'drivers/mtd/devices')
| -rw-r--r-- | drivers/mtd/devices/block2mtd.c | 13 |
1 files changed, 11 insertions, 2 deletions
diff --git a/drivers/mtd/devices/block2mtd.c b/drivers/mtd/devices/block2mtd.c index 2cf0cc6a4189..a9e2d3b38aeb 100644 --- a/drivers/mtd/devices/block2mtd.c +++ b/drivers/mtd/devices/block2mtd.c @@ -234,6 +234,7 @@ static void block2mtd_free_device(struct block2mtd_dev *dev) /* FIXME: ensure that mtd->size % erase_size == 0 */ static struct block2mtd_dev *add_device(char *devname, int erase_size) { + const fmode_t mode = FMODE_READ | FMODE_WRITE; struct block_device *bdev; struct block2mtd_dev *dev; char *name; @@ -246,7 +247,7 @@ static struct block2mtd_dev *add_device(char *devname, int erase_size) return NULL; /* Get a handle on the device */ - bdev = open_bdev_exclusive(devname, FMODE_READ|FMODE_WRITE, NULL); + bdev = open_bdev_exclusive(devname, mode, dev); #ifndef MODULE if (IS_ERR(bdev)) { @@ -255,7 +256,15 @@ static struct block2mtd_dev *add_device(char *devname, int erase_size) dev_t devt = name_to_dev_t(devname); if (devt) { - bdev = open_by_devnum(devt, FMODE_WRITE | FMODE_READ); + bdev = open_by_devnum(devt, mode); + if (!IS_ERR(bdev)) { + int ret; + ret = bd_claim(bdev, dev); + if (ret) { + blkdev_put(bdev, mode); + bdev = ERR_PTR(ret); + } + } } } #endif |