diff options
Diffstat (limited to 'fs/block_dev.c')
| -rw-r--r-- | fs/block_dev.c | 48 |
1 files changed, 32 insertions, 16 deletions
diff --git a/fs/block_dev.c b/fs/block_dev.c index 257b00e98428..610e8e0b04b8 100644 --- a/fs/block_dev.c +++ b/fs/block_dev.c @@ -762,7 +762,19 @@ static struct block_device *bd_start_claiming(struct block_device *bdev, if (!disk) return ERR_PTR(-ENXIO); - whole = bdget_disk(disk, 0); + /* + * Normally, @bdev should equal what's returned from bdget_disk() + * if partno is 0; however, some drivers (floppy) use multiple + * bdev's for the same physical device and @bdev may be one of the + * aliases. Keep @bdev if partno is 0. This means claimer + * tracking is broken for those devices but it has always been that + * way. + */ + if (partno) + whole = bdget_disk(disk, 0); + else + whole = bdgrab(bdev); + module_put(disk->fops->owner); put_disk(disk); if (!whole) @@ -1120,6 +1132,15 @@ static int __blkdev_get(struct block_device *bdev, fmode_t mode, int for_part) goto restart; } } + + if (!ret && !bdev->bd_openers) { + bd_set_size(bdev,(loff_t)get_capacity(disk)<<9); + bdi = blk_get_backing_dev_info(bdev); + if (bdi == NULL) + bdi = &default_backing_dev_info; + bdev_inode_switch_bdi(bdev->bd_inode, bdi); + } + /* * If the device is invalidated, rescan partition * if open succeeded or failed with -ENOMEDIUM. @@ -1130,14 +1151,6 @@ static int __blkdev_get(struct block_device *bdev, fmode_t mode, int for_part) rescan_partitions(disk, bdev); if (ret) goto out_clear; - - if (!bdev->bd_openers) { - bd_set_size(bdev,(loff_t)get_capacity(disk)<<9); - bdi = blk_get_backing_dev_info(bdev); - if (bdi == NULL) - bdi = &default_backing_dev_info; - bdev_inode_switch_bdi(bdev->bd_inode, bdi); - } } else { struct block_device *whole; whole = bdget_disk(disk, 0); @@ -1237,6 +1250,8 @@ int blkdev_get(struct block_device *bdev, fmode_t mode, void *holder) res = __blkdev_get(bdev, mode, 0); if (whole) { + struct gendisk *disk = whole->bd_disk; + /* finish claiming */ mutex_lock(&bdev->bd_mutex); spin_lock(&bdev_lock); @@ -1263,15 +1278,16 @@ int blkdev_get(struct block_device *bdev, fmode_t mode, void *holder) spin_unlock(&bdev_lock); /* - * Block event polling for write claims. Any write - * holder makes the write_holder state stick until all - * are released. This is good enough and tracking - * individual writeable reference is too fragile given - * the way @mode is used in blkdev_get/put(). + * Block event polling for write claims if requested. Any + * write holder makes the write_holder state stick until + * all are released. This is good enough and tracking + * individual writeable reference is too fragile given the + * way @mode is used in blkdev_get/put(). */ - if (!res && (mode & FMODE_WRITE) && !bdev->bd_write_holder) { + if (!res && (mode & FMODE_WRITE) && !bdev->bd_write_holder && + (disk->flags & GENHD_FL_BLOCK_EVENTS_ON_EXCL_WRITE)) { bdev->bd_write_holder = true; - disk_block_events(bdev->bd_disk); + disk_block_events(disk); } mutex_unlock(&bdev->bd_mutex); |