linux/fs/block_dev.c, branch v2.6.32

block: use after free bug in __blkdev_get

2009-10-26T14:27:11Z

commit 0762b8bde9729f10f8e6249809660ff2ec3ad735 (from 14 months ago) introduced a use-after-free bug which has just recently started manifesting in my md testing. I tried git bisect to find out what caused the bug to start manifesting, and it could have been the recent change to blk_unregister_queue (48c0d4d4c04) but the results were inconclusive. This patch certainly fixes my symptoms and looks correct as the two calls are now in the same order as elsewhere in that function. Signed-off-by: NeilBrown Acked-by: Tejun Heo Signed-off-by: Jens Axboe

freeze_bdev: grab active reference to frozen superblocks

2009-09-24T11:47:41Z

Currently we held s_umount while a filesystem is frozen, despite that we might return to userspace and unlock it from a different process. Instead grab an active reference to keep the file system busy and add an explicit check for frozen filesystems in remount and reject the remount instead of blocking on s_umount. Add a new get_active_super helper to super.c for use by freeze_bdev that grabs an active reference to a superblock from a given block device. Signed-off-by: Christoph Hellwig Signed-off-by: Al Viro

freeze_bdev: kill bd_mount_sem

2009-09-24T11:47:39Z

Now that we have the freeze count there is not much reason for bd_mount_sem anymore. The actual freeze/thaw operations are serialized using the bd_fsfreeze_mutex, and the only other place we take bd_mount_sem is get_sb_bdev which tries to prevent mounting a filesystem while the block device is frozen. Instead of add a check for bd_fsfreeze_count and return -EBUSY if a filesystem is frozen. While that is a change in user visible behaviour a failing mount is much better for this case rather than having the mount process stuck uninterruptible for a long time. Signed-off-by: Christoph Hellwig Signed-off-by: Al Viro

const: make block_device_operations const

2009-09-22T14:17:25Z

Signed-off-by: Alexey Dobriyan Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

fs: remove bdev->bd_inode_backing_dev_info

2009-09-16T13:16:18Z

It has been unused since it was introduced in: commit 520808bf20e90fdbdb320264ba7dd5cf9d47dcac Author: Andrew Morton Date: Fri May 21 00:46:17 2004 -0700 [PATCH] block device layer: separate backing_dev_info infrastructure So lets just kill it. Acked-by: Jan Kara Signed-off-by: Jens Axboe

vfs: Rename generic_file_aio_write_nolock

2009-09-14T15:08:15Z

generic_file_aio_write_nolock() is now used only by block devices and raw character device. Filesystems should use __generic_file_aio_write() in case generic_file_aio_write() doesn't suit them. So rename the function to blkdev_aio_write() and move it to fs/blockdev.c. Signed-off-by: Christoph Hellwig Signed-off-by: Jan Kara

PM / Hibernate: Replace bdget call with simple atomic_inc of i_count

2009-07-29T19:07:55Z

Create bdgrab(). This function copies an existing reference to a block_device. It is safe to call from any context. Hibernation code wishes to copy a reference to the active swap device. Right now it calls bdget() under a spinlock, but this is wrong because bdget() can sleep. It doesn't need a full bdget() because we already hold a reference to active swap devices (and the spinlock protects against swapoff). Fixes http://bugzilla.kernel.org/show_bug.cgi?id=13827 Signed-off-by: Alan Jenkins Signed-off-by: Rafael J. Wysocki

vfs: Rename fsync_super() to sync_filesystem() (version 4)

2009-06-12T01:36:04Z

Rename the function so that it better describe what it really does. Also remove the unnecessary include of buffer_head.h. Signed-off-by: Jan Kara Signed-off-by: Al Viro

vfs: Make sys_sync() use fsync_super() (version 4)

2009-06-12T01:36:03Z

It is unnecessarily fragile to have two places (fsync_super() and do_sync()) doing data integrity sync of the filesystem. Alter __fsync_super() to accommodate needs of both callers and use it. So after this patch __fsync_super() is the only place where we gather all the calls needed to properly send all data on a filesystem to disk. Nice bonus is that we get a complete livelock avoidance and write_supers() is now only used for periodic writeback of superblocks. sync_blockdevs() introduced a couple of patches ago is gone now. [build fixes folded] Signed-off-by: Jan Kara Signed-off-by: Al Viro

vfs: Make __fsync_super() a static function (version 4)

2009-06-12T01:36:03Z

__fsync_super() does the same thing as fsync_super(). So change the only caller to use fsync_super() and make __fsync_super() static. This removes unnecessarily duplicated call to sync_blockdev() and prepares ground for the changes to __fsync_super() in the following patches. Signed-off-by: Jan Kara Signed-off-by: Al Viro