diff options
author | Alexander Stein <alexander.stein@systec-electronic.com> | 2012-01-10 13:26:58 +0100 |
---|---|---|
committer | David Woodhouse <David.Woodhouse@intel.com> | 2012-03-27 01:11:11 +0200 |
commit | 70d5098a4b1551864dd7df43f67b7f606a1a6438 (patch) | |
tree | 288f6f9cdb1866ea9648c6590448254c40af2c81 | |
parent | mtd: pmc551: fix signedness bug in init_pmc551() (diff) | |
download | linux-70d5098a4b1551864dd7df43f67b7f606a1a6438.tar.xz linux-70d5098a4b1551864dd7df43f67b7f606a1a6438.zip |
mtd: mtdblock: call mtd_sync() only if opened for write
Because it is useless to call it if the device is opened in R/O mode, and also
harmful: on CFI NOR flash it may block for long time waiting for erase
operations to complete is another partition with a R/W file-system on this
chip.
Artem Bityutskiy: write commit message, amend the patch to match the latest
tree (we use mtd_sync(), not mtd->sync() nowadays).
Signed-off-by: Alexander Stein <alexander.stein@systec-electronic.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
-rw-r--r-- | drivers/mtd/mtd_blkdevs.c | 1 | ||||
-rw-r--r-- | drivers/mtd/mtdblock.c | 8 | ||||
-rw-r--r-- | include/linux/mtd/blktrans.h | 1 |
3 files changed, 8 insertions, 2 deletions
diff --git a/drivers/mtd/mtd_blkdevs.c b/drivers/mtd/mtd_blkdevs.c index 424ca5f93c6c..f1f06715d4e0 100644 --- a/drivers/mtd/mtd_blkdevs.c +++ b/drivers/mtd/mtd_blkdevs.c @@ -233,6 +233,7 @@ static int blktrans_open(struct block_device *bdev, fmode_t mode) ret = __get_mtd_device(dev->mtd); if (ret) goto error_release; + dev->file_mode = mode; unlock: dev->open++; diff --git a/drivers/mtd/mtdblock.c b/drivers/mtd/mtdblock.c index af6591237b9b..6c6d80736fad 100644 --- a/drivers/mtd/mtdblock.c +++ b/drivers/mtd/mtdblock.c @@ -321,8 +321,12 @@ static int mtdblock_release(struct mtd_blktrans_dev *mbd) mutex_unlock(&mtdblk->cache_mutex); if (!--mtdblk->count) { - /* It was the last usage. Free the cache */ - mtd_sync(mbd->mtd); + /* + * It was the last usage. Free the cache, but only sync if + * opened for writing. + */ + if (mbd->file_mode & FMODE_WRITE) + mtd_sync(mbd->mtd); vfree(mtdblk->cache_data); } diff --git a/include/linux/mtd/blktrans.h b/include/linux/mtd/blktrans.h index 1bbd9f289245..ed270bd2e4df 100644 --- a/include/linux/mtd/blktrans.h +++ b/include/linux/mtd/blktrans.h @@ -47,6 +47,7 @@ struct mtd_blktrans_dev { struct request_queue *rq; spinlock_t queue_lock; void *priv; + fmode_t file_mode; }; struct mtd_blktrans_ops { |