kernel/git/stable/linux.git/fs/btrfs/backref.c, branch linux-3.15.y

Btrfs: fix scrub_print_warning to handle skinny metadata extents

2014-07-01T03:14:03+00:00

commit 6eda71d0c030af0fc2f68aaa676e6d445600855b upstream. The skinny extents are intepreted incorrectly in scrub_print_warning(), and end up hitting the BUG() in btrfs_extent_inline_ref_size. Reported-by: Konstantinos Skarlatos Signed-off-by: Liu Bo Signed-off-by: Chris Mason Signed-off-by: Greg Kroah-Hartman

Btrfs: use right type to get real comparison

2014-07-01T03:14:03+00:00

commit cd857dd6bc2ae9ecea14e75a34e8a8fdc158e307 upstream. We want to make sure the point is still within the extent item, not to verify the memory it's pointing to. Signed-off-by: Liu Bo Signed-off-by: Chris Mason Signed-off-by: Greg Kroah-Hartman

Btrfs: don't check nodes for extent items

2014-07-01T03:14:03+00:00

commit 8a56457f5f8fa7c2698ffae8545214c5b96a2cb5 upstream. The backref code was looking at nodes as well as leaves when we tried to populate extent item entries. This is not good, and although we go away with it for the most part because we'd skip where disk_bytenr != random_memory, sometimes random_memory would match and suddenly boom. This fixes that problem. Thanks, Signed-off-by: Josef Bacik Signed-off-by: Chris Mason Signed-off-by: Greg Kroah-Hartman

Btrfs: remove transaction from send

2014-04-07T00:39:30+00:00

Lets try this again. We can deadlock the box if we send on a box and try to write onto the same fs with the app that is trying to listen to the send pipe. This is because the writer could get stuck waiting for a transaction commit which is being blocked by the send. So fix this by making sure looking at the commit roots is always going to be consistent. We do this by keeping track of which roots need to have their commit roots swapped during commit, and then taking the commit_root_sem and swapping them all at once. Then make sure we take a read lock on the commit_root_sem in cases where we search the commit root to make sure we're always looking at a consistent view of the commit roots. Previously we had problems with this because we would swap a fs tree commit root and then swap the extent tree commit root independently which would cause the backref walking code to screw up sometimes. With this patch we no longer deadlock and pass all the weird send/receive corner cases. Thanks, Reportedy-by: Hugo Mills Signed-off-by: Josef Bacik Signed-off-by: Chris Mason

Btrfs: take into account total references when doing backref lookup

2014-03-21T22:28:09+00:00

I added an optimization for large files where we would stop searching for backrefs once we had looked at the number of references we currently had for this extent. This works great most of the time, but for snapshots that point to this extent and has changes in the original root this assumption falls on it face. So keep track of any delayed ref mods made and add in the actual ref count as reported by the extent item and use that to limit how far down an inode we'll search for extents. Thanks, Reportedy-by: Hugo Mills Signed-off-by: Josef Bacik Reported-by: Hugo Mills Tested-by: Hugo Mills Signed-off-by: Chris Mason

Btrfs: skip locking when searching commit root

2014-03-10T19:16:55+00:00

We won't change commit root, skip locking dance with commit root when walking backrefs, this can speed up btrfs send operations. Signed-off-by: Wang Shilong Signed-off-by: Josef Bacik

Btrfs: switch to btrfs_previous_extent_item()

2014-03-10T19:15:54+00:00

Since we have introduced btrfs_previous_extent_item() to search previous extent item, just switch into it. Signed-off-by: Wang Shilong Reviewed-by: Filipe Manana Signed-off-by: Josef Bacik

Btrfs: only add roots if necessary in find_parent_nodes()

2014-03-10T19:15:41+00:00

find_all_leafs() dosen't need add all roots actually, add roots only if we need, this can avoid unnecessary ulist dance. Signed-off-by: Wang Shilong Signed-off-by: Josef Bacik

Btrfs: fix memory leaks on walking backrefs failure

2014-01-29T15:06:26+00:00

When walking backrefs, we may iterate every inode's extent and add/merge them into ulist, and the caller will free memory from ulist. However, if we fail to allocate inode's extents element memory or ulist_add() fail to allocate memory, we won't add allocated memory into ulist, and the caller won't free some allocated memory thus memory leaks happen. Signed-off-by: Wang Shilong Signed-off-by: Josef Bacik Signed-off-by: Chris Mason

Btrfs: add a reschedule point in btrfs_find_all_roots()

2014-01-29T15:06:25+00:00

I can easily trigger the following warnings when enabling quota in my virtual machine(running Opensuse), Steps are firstly creating a subvolume full of fragment extents, and then create many snapshots (500 in my test case). [ 2362.808459] BUG: soft lockup - CPU#0 stuck for 22s! [btrfs-qgroup-re:1970] [ 2362.809023] task: e4af8450 ti: e371c000 task.ti: e371c000 [ 2362.809026] EIP: 0060:[] EFLAGS: 00000246 CPU: 0 [ 2362.809049] EIP is at __merge_refs+0x5e/0x100 [btrfs] [ 2362.809051] EAX: 00000000 EBX: cfadbcf0 ECX: 00000000 EDX: cfadbcb0 [ 2362.809052] ESI: dd8d3370 EDI: e371dde0 EBP: e371dd6c ESP: e371dd5c [ 2362.809054] DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068 [ 2362.809055] CR0: 80050033 CR2: ac454d50 CR3: 009a9000 CR4: 001407d0 [ 2362.809099] Stack: [ 2362.809100] 00000001 e371dde0 dfcc6890 f29f8000 e371de28 fa39016d 00000011 00000001 [ 2362.809105] 99bfc000 00000000 93928000 00000000 00000001 00000050 e371dda8 00000001 [ 2362.809109] f3a31000 f3413000 00000001 e371ddb8 000040a8 00000202 00000000 00000023 [ 2362.809113] Call Trace: [ 2362.809136] [] find_parent_nodes+0x34d/0x1280 [btrfs] [ 2362.809156] [] btrfs_find_all_roots+0xb2/0x110 [btrfs] [ 2362.809174] [] btrfs_qgroup_rescan_worker+0x358/0x7a0 [btrfs] [ 2362.809180] [] ? lock_timer_base.isra.39+0x1e/0x40 [ 2362.809199] [] worker_loop+0xff/0x470 [btrfs] [ 2362.809204] [] ? __wake_up_locked+0x1a/0x20 [ 2362.809221] [] ? btrfs_queue_worker+0x2b0/0x2b0 [btrfs] [ 2362.809225] [] kthread+0x9c/0xb0 [ 2362.809229] [] ret_from_kernel_thread+0x1b/0x30 [ 2362.809233] [] ? kthread_create_on_node+0x110/0x110 By adding a reschedule point at the end of btrfs_find_all_roots(), i no longer hit these warnings. Cc: Josef Bacik Signed-off-by: Wang Shilong Reviewed-by: David Sterba Signed-off-by: Josef Bacik Signed-off-by: Chris Mason