kernel.git/fs/btrfs/super.c, branch linux-4.3.y

Merge branch 'for-linus-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs

2015-09-25T19:08:41Z

Pull btrfs fixes from Chris Mason: "This is an assorted set I've been queuing up: Jeff Mahoney tracked down a tricky one where we ended up starting IO on the wrong mapping for special files in btrfs_evict_inode. A few people reported this one on the list. Filipe found (and provided a test for) a difficult bug in reading compressed extents, and Josef fixed up some quota record keeping with snapshot deletion. Chandan killed off an accounting bug during DIO that lead to WARN_ONs as we freed inodes" * 'for-linus-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: Btrfs: keep dropped roots in cache until transaction commit Btrfs: Direct I/O: Fix space accounting btrfs: skip waiting on ordered range for special files Btrfs: fix read corruption of compressed and shared extents Btrfs: remove unnecessary locking of cleaner_mutex to avoid deadlock Btrfs: don't initialize a space info as full to prevent ENOSPC

Btrfs: remove unnecessary locking of cleaner_mutex to avoid deadlock

2015-09-10T10:27:57Z

After commmit e44163e17796 ("btrfs: explictly delete unused block groups in close_ctree and ro-remount"), added in the 4.3 merge window, we have calls to btrfs_delete_unused_bgs() while holding the cleaner_mutex. This can cause a deadlock with a concurrent block group relocation (when a filesystem balance or shrink operation is in progress for example) because btrfs_delete_unused_bgs() locks delete_unused_bgs_mutex and the relocation path locks first delete_unused_bgs_mutex and then it locks cleaner_mutex, resulting in a classic ABBA deadlock: CPU 0 CPU 1 lock fs_info->cleaner_mutex __btrfs_balance() || btrfs_shrink_device() lock fs_info->delete_unused_bgs_mutex btrfs_relocate_chunk() btrfs_relocate_block_group() lock fs_info->cleaner_mutex btrfs_delete_unused_bgs() lock fs_info->delete_unused_bgs_mutex Fix this by not taking the cleaner_mutex before calling btrfs_delete_unused_bgs() because it's no longer needed after commit 67c5e7d464bc ("Btrfs: fix race between balance and unused block group deletion"). The mutex fs_info->delete_unused_bgs_mutex, the spinlock fs_info->unused_bgs_lock and a block group's spinlock are enough to get correct serialization between tasks running relocation and unused block group deletion (as well as between multiple tasks concurrently calling btrfs_delete_unused_bgs()). This issue was discussed (in the mailing list) during the review of the patch titled "btrfs: explictly delete unused block groups in close_ctree and ro-remount" and it was agreed that acquiring the cleaner mutex had to be dropped after the patch titled "Btrfs: fix race between balance and unused block group deletion" got merged (both patches were submitted at about the same time, but one landed in kernel 4.2 and the other in the 4.3 merge window). Signed-off-by: Filipe Manana

Merge branch 'for-linus-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs

2015-09-05T22:14:43Z

Pull btrfs updates from Chris Mason: "This has Jeff Mahoney's long standing trim patch that fixes corners where trims were missing. Omar has some raid5/6 fixes, especially for using scrub and device replace when devices are missing. Zhao Lie continues cleaning and fixing things, this series fixes some really hard to hit corners in xfstests. I had to pull it last merge window due to some deadlocks, but those are now resolved. I added support for Tejun's new blkio controllers. It seems to work well for single devices, we'll expand to multi-device as well" * 'for-linus-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (47 commits) btrfs: fix compile when block cgroups are not enabled Btrfs: fix file read corruption after extent cloning and fsync Btrfs: check if previous transaction aborted to avoid fs corruption btrfs: use __GFP_NOFAIL in alloc_btrfs_bio btrfs: Prevent from early transaction abort btrfs: Remove unused arguments in tree-log.c btrfs: Remove useless condition in start_log_trans() Btrfs: add support for blkio controllers Btrfs: remove unused mutex from struct 'btrfs_fs_info' Btrfs: fix parity scrub of RAID 5/6 with missing device Btrfs: fix device replace of a missing RAID 5/6 device Btrfs: add RAID 5/6 BTRFS_RBIO_REBUILD_MISSING operation Btrfs: count devices correctly in readahead during RAID 5/6 replace Btrfs: remove misleading handling of missing device scrub btrfs: fix clone / extent-same deadlocks Btrfs: fix defrag to merge tail file extent Btrfs: fix warning in backref walking btrfs: Add WARN_ON() for double lock in btrfs_tree_lock() btrfs: Remove root argument in extent_data_ref_count() btrfs: Fix wrong comment of btrfs_alloc_tree_block() ...

Merge branch 'jeffm-discard-4.3' into for-linus-4.3

2015-08-09T14:35:33Z

Btrfs: add support for blkio controllers

2015-08-09T14:35:06Z

This attaches accounting information to bios as we submit them so the new blkio controllers can throttle on btrfs filesystems. Not much is required, we're just associating bios with blkcgs during clone, calling wbc_init_bio()/wbc_account_io() during writepages submission, and attaching the bios to the current context during direct IO. Finally if we are splitting bios during btrfs_map_bio, this attaches accounting information to the split. The end result is able to throttle nicely on single disk filesystems. A little more work is required for multi-device filesystems. Signed-off-by: Chris Mason

char: make misc_deregister a void function

2015-08-05T17:35:49Z

With well over 200+ users of this api, there are a mere 12 users that actually checked the return value of this function. And all of them really didn't do anything with that information as the system or module was shutting down no matter what. So stop pretending like it matters, and just return void from misc_deregister(). If something goes wrong in the call, you will get a WARNING splat in the syslog so you know how to fix up your driver. Other than that, there's nothing that can go wrong. Cc: Alasdair Kergon Cc: Neil Brown Cc: Oleg Drokin Cc: Andreas Dilger Cc: "Michael S. Tsirkin" Cc: Wim Van Sebroeck Cc: Christine Caulfield Cc: David Teigland Cc: Mark Fasheh Acked-by: Joel Becker Acked-by: Alexandre Belloni Acked-by: Alessandro Zummo Acked-by: Mike Snitzer Signed-off-by: Greg Kroah-Hartman

btrfs: add missing discards when unpinning extents with -o discard

2015-07-29T15:15:29Z

When we clear the dirty bits in btrfs_delete_unused_bgs for extents in the empty block group, it results in btrfs_finish_extent_commit being unable to discard the freed extents. The block group removal patch added an alternate path to forget extents other than btrfs_finish_extent_commit. As a result, any extents that would be freed when the block group is removed aren't discarded. In my test run, with a large copy of mixed sized files followed by removal, it left nearly 2/3 of extents undiscarded. To clean up the block groups, we add the removed block group onto a list that will be discarded after transaction commit. Signed-off-by: Jeff Mahoney Reviewed-by: Filipe Manana Tested-by: Filipe Manana Signed-off-by: Chris Mason

btrfs: explictly delete unused block groups in close_ctree and ro-remount

2015-07-29T15:15:27Z

The cleaner thread may already be sleeping by the time we enter close_ctree. If that's the case, we'll skip removing any unused block groups queued for removal, even during a normal umount. They'll be cleaned up automatically at next mount, but users expect a umount to be a clean synchronization point, especially when used on thin-provisioned storage with -odiscard. We also explicitly remove unused block groups in the ro-remount path for the same reason. Signed-off-by: Jeff Mahoney Reviewed-by: Filipe Manana Tested-by: Filipe Manana Signed-off-by: Chris Mason

Btrfs: show subvol= and subvolid= in /proc/mounts

2015-06-03T11:03:02Z

Now that we're guaranteed to have a meaningful root dentry, we can just export seq_dentry() and use it in btrfs_show_options(). The subvolume ID is easy to get and can also be useful, so put that in there, too. Reviewed-by: David Sterba Signed-off-by: Omar Sandoval Signed-off-by: Chris Mason

Btrfs: unify subvol= and subvolid= mounting

2015-06-03T11:03:01Z

Currently, mounting a subvolume with subvolid= takes a different code path than mounting with subvol=. This isn't really a big deal except for the fact that mounts done with subvolid= or the default subvolume don't have a dentry that's connected to the dentry tree like in the subvol= case. To unify the code paths, when given subvolid= or using the default subvolume ID, translate it into a subvolume name by walking ROOT_BACKREFs in the root tree and INODE_REFs in the filesystem trees. Reviewed-by: David Sterba Signed-off-by: Omar Sandoval Signed-off-by: Chris Mason