summaryrefslogtreecommitdiff
path: root/fs/btrfs/extent-tree.c
AgeCommit message (Collapse)AuthorFilesLines
2016-07-27Merge branch 'for-4.8/core' of git://git.kernel.dk/linux-blockLinus Torvalds1-1/+1
Pull core block updates from Jens Axboe: - the big change is the cleanup from Mike Christie, cleaning up our uses of command types and modified flags. This is what will throw some merge conflicts - regression fix for the above for btrfs, from Vincent - following up to the above, better packing of struct request from Christoph - a 2038 fix for blktrace from Arnd - a few trivial/spelling fixes from Bart Van Assche - a front merge check fix from Damien, which could cause issues on SMR drives - Atari partition fix from Gabriel - convert cfq to highres timers, since jiffies isn't granular enough for some devices these days. From Jan and Jeff - CFQ priority boost fix idle classes, from me - cleanup series from Ming, improving our bio/bvec iteration - a direct issue fix for blk-mq from Omar - fix for plug merging not involving the IO scheduler, like we do for other types of merges. From Tahsin - expose DAX type internally and through sysfs. From Toshi and Yigal * 'for-4.8/core' of git://git.kernel.dk/linux-block: (76 commits) block: Fix front merge check block: do not merge requests without consulting with io scheduler block: Fix spelling in a source code comment block: expose QUEUE_FLAG_DAX in sysfs block: add QUEUE_FLAG_DAX for devices to advertise their DAX support Btrfs: fix comparison in __btrfs_map_block() block: atari: Return early for unsupported sector size Doc: block: Fix a typo in queue-sysfs.txt cfq-iosched: Charge at least 1 jiffie instead of 1 ns cfq-iosched: Fix regression in bonnie++ rewrite performance cfq-iosched: Convert slice_resid from u64 to s64 block: Convert fifo_time from ulong to u64 blktrace: avoid using timespec block/blk-cgroup.c: Declare local symbols static block/bio-integrity.c: Add #include "blk.h" block/partition-generic.c: Remove a set-but-not-used variable block: bio: kill BIO_MAX_SIZE cfq-iosched: temporarily boost queue priority for idle classes block: drbd: avoid to use BIO_MAX_SIZE block: bio: remove BIO_MAX_SECTORS ...
2016-06-23btrfs: fix deadlock in delayed_ref_async_startChris Mason1-9/+11
"Btrfs: track transid for delayed ref flushing" was deadlocking on btrfs_attach_transaction because its not safe to call from the async delayed ref start code. This commit brings back btrfs_join_transaction instead and checks for a blocked commit. Signed-off-by: Josef Bacik <jbacik@fb.com> Signed-off-by: Chris Mason <clm@fb.com>
2016-06-23Btrfs: track transid for delayed ref flushingJosef Bacik1-3/+12
Using the offwakecputime bpf script I noticed most of our time was spent waiting on the delayed ref throttling. This is what is supposed to happen, but sometimes the transaction can commit and then we're waiting for throttling that doesn't matter anymore. So change this stuff to be a little smarter by tracking the transid we were in when we initiated the throttling. If the transaction we get is different then we can just bail out. This resulted in a 50% speedup in my fs_mark test, and reduced the amount of time spent throttling by 60 seconds over the entire run (which is about 30 minutes). Thanks, Signed-off-by: Josef Bacik <jbacik@fb.com> Signed-off-by: Chris Mason <clm@fb.com>
2016-06-17btrfs: account for non-CoW'd blocks in btrfs_abort_transactionJeff Mahoney1-1/+1
The test for !trans->blocks_used in btrfs_abort_transaction is insufficient to determine whether it's safe to drop the transaction handle on the floor. btrfs_cow_block, informed by should_cow_block, can return blocks that have already been CoW'd in the current transaction. trans->blocks_used is only incremented for new block allocations. If an operation overlaps the blocks in the current transaction entirely and must abort the transaction, we'll happily let it clean up the trans handle even though it may have modified the blocks and will commit an incomplete operation. In the long-term, I'd like to do closer tracking of when the fs is actually modified so we can still recover as gracefully as possible, but that approach will need some discussion. In the short term, since this is the only code using trans->blocks_used, let's just switch it to a bool indicating whether any blocks were used and set it when should_cow_block returns false. Cc: stable@vger.kernel.org # 3.4+ Signed-off-by: Jeff Mahoney <jeffm@suse.com> Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2016-06-17Btrfs: check if extent buffer is aligned to sectorsizeLiu Bo1-4/+6
Thanks to fuzz testing, we can pass an invalid bytenr to extent buffer via alloc_extent_buffer(). An unaligned eb can have more pages than it should have, which ends up extent buffer's leak or some corrupted content in extent buffer. This adds a warning to let us quickly know what was happening. Now that alloc_extent_buffer() no more returns NULL, this changes its caller and callers of its caller to match with the new error handling. Signed-off-by: Liu Bo <bo.li.liu@oracle.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2016-06-07btrfs: update __btrfs_map_block for REQ_OP transitionMike Christie1-1/+1
We no longer pass in a bitmap of rq_flag_bits bits to __btrfs_map_block. It will always be a REQ_OP, or the btrfs specific REQ_GET_READ_MIRRORS, so this drops the bit tests. Signed-off-by: Mike Christie <mchristi@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-05-31Btrfs: fix race between device replace and discardFilipe Manana1-0/+6
While we are finishing a device replace operation, we can make a discard operation (fs mounted with -o discard) do an invalid memory access like the one reported by the following trace: [ 3206.384654] general protection fault: 0000 [#1] PREEMPT SMP [ 3206.387520] Modules linked in: dm_mod btrfs crc32c_generic xor raid6_pq acpi_cpufreq tpm_tis psmouse tpm ppdev sg parport_pc evdev i2c_piix4 parport processor serio_raw i2c_core pcspkr button loop autofs4 ext4 crc16 jbd2 mbcache sr_mod cdrom ata_generic sd_mod virtio_scsi ata_piix libata virtio_pci virtio_ring scsi_mod e1000 virtio floppy [last unloaded: btrfs] [ 3206.388595] CPU: 14 PID: 29194 Comm: fsstress Not tainted 4.6.0-rc7-btrfs-next-29+ #1 [ 3206.388595] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS by qemu-project.org 04/01/2014 [ 3206.388595] task: ffff88017ace0100 ti: ffff880171b98000 task.ti: ffff880171b98000 [ 3206.388595] RIP: 0010:[<ffffffff8124d233>] [<ffffffff8124d233>] blkdev_issue_discard+0x5c/0x2a7 [ 3206.388595] RSP: 0018:ffff880171b9bb80 EFLAGS: 00010246 [ 3206.388595] RAX: ffff880171b9bc28 RBX: 000000000090d000 RCX: 0000000000000000 [ 3206.388595] RDX: ffffffff82fa1b48 RSI: ffffffff8179f46c RDI: ffffffff82fa1b48 [ 3206.388595] RBP: ffff880171b9bcc0 R08: 0000000000000000 R09: 0000000000000001 [ 3206.388595] R10: ffff880171b9bce0 R11: 000000000090f000 R12: ffff880171b9bbe8 [ 3206.388595] R13: 0000000000000010 R14: 0000000000004868 R15: 6b6b6b6b6b6b6b6b [ 3206.388595] FS: 00007f6182e4e700(0000) GS:ffff88023fdc0000(0000) knlGS:0000000000000000 [ 3206.388595] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 3206.388595] CR2: 00007f617c2bbb18 CR3: 000000017ad9c000 CR4: 00000000000006e0 [ 3206.388595] Stack: [ 3206.388595] 0000000000004878 0000000000000000 0000000002400040 0000000000000000 [ 3206.388595] 0000000000000000 ffff880171b9bbe8 ffff880171b9bbb0 ffff880171b9bbb0 [ 3206.388595] ffff880171b9bbc0 ffff880171b9bbc0 ffff880171b9bbd0 ffff880171b9bbd0 [ 3206.388595] Call Trace: [ 3206.388595] [<ffffffffa042899e>] btrfs_issue_discard+0x12f/0x143 [btrfs] [ 3206.388595] [<ffffffffa042899e>] ? btrfs_issue_discard+0x12f/0x143 [btrfs] [ 3206.388595] [<ffffffffa042e862>] btrfs_discard_extent+0x87/0xde [btrfs] [ 3206.388595] [<ffffffffa04303b5>] btrfs_finish_extent_commit+0xb2/0x1df [btrfs] [ 3206.388595] [<ffffffff8149c246>] ? __mutex_unlock_slowpath+0x150/0x15b [ 3206.388595] [<ffffffffa04464c4>] btrfs_commit_transaction+0x7fc/0x980 [btrfs] [ 3206.388595] [<ffffffff8149c246>] ? __mutex_unlock_slowpath+0x150/0x15b [ 3206.388595] [<ffffffffa0459af6>] btrfs_sync_file+0x38f/0x428 [btrfs] [ 3206.388595] [<ffffffff811a8292>] vfs_fsync_range+0x8c/0x9e [ 3206.388595] [<ffffffff811a82c0>] vfs_fsync+0x1c/0x1e [ 3206.388595] [<ffffffff811a8417>] do_fsync+0x31/0x4a [ 3206.388595] [<ffffffff811a8637>] SyS_fsync+0x10/0x14 [ 3206.388595] [<ffffffff8149e025>] entry_SYSCALL_64_fastpath+0x18/0xa8 [ 3206.388595] [<ffffffff81100c6b>] ? time_hardirqs_off+0x9/0x14 [ 3206.388595] [<ffffffff8108e87d>] ? trace_hardirqs_off_caller+0x1f/0xaa This happens because when we call btrfs_map_block() from btrfs_discard_extent() to get a btrfs_bio structure, the device replace operation has not finished yet, but before we use the device of one of the stripes from the returned btrfs_bio structure, the device object is freed. This is illustrated by the following diagram. CPU 1 CPU 2 btrfs_dev_replace_start() (...) btrfs_dev_replace_finishing() btrfs_start_transaction() btrfs_commit_transaction() (...) btrfs_sync_file() btrfs_start_transaction() (...) btrfs_commit_transaction() btrfs_finish_extent_commit() btrfs_discard_extent() btrfs_map_block() --> returns a struct btrfs_bio with a stripe that has a device field pointing to source device of the replace operation (the device that is being replaced) mutex_lock(&uuid_mutex) mutex_lock(&fs_info->fs_devices->device_list_mutex) mutex_lock(&fs_info->chunk_mutex) btrfs_dev_replace_update_device_in_mapping_tree() --> iterates the mapping tree and for each extent map that has a stripe pointing to the source device, it updates the stripe to point to the target device instead btrfs_rm_dev_replace_blocked() --> waits for fs_info->bio_counter to go down to 0 btrfs_rm_dev_replace_remove_srcdev() --> removes source device from the list of devices mutex_unlock(&fs_info->chunk_mutex) mutex_unlock(&fs_info->fs_devices->device_list_mutex) mutex_unlock(&uuid_mutex) btrfs_rm_dev_replace_free_srcdev() --> frees the source device --> iterates over all stripes of the returned struct btrfs_bio --> for each stripe it dereferences its device pointer --> it ends up finding a pointer to the device used as the source device for the replace operation and that was already freed So fix this by surrounding the call to btrfs_map_block(), and the code that uses the returned struct btrfs_bio, with calls to btrfs_bio_counter_inc_blocked() and btrfs_bio_counter_dec(), so that the finishing phase of the device replace operation blocks until the the bio counter decreases to zero before it frees the source device. This is the same approach we do at btrfs_map_bio() for example. Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: Josef Bacik <jbacik@fb.com>
2016-05-25Merge branch 'cleanups-4.7' into for-chris-4.7-20160525David Sterba1-24/+24
2016-05-25btrfs: fix string and comment grammatical issues and typosNicholas D Steeves1-16/+16
Signed-off-by: Nicholas D Steeves <nsteeves@gmail.com> Signed-off-by: David Sterba <dsterba@suse.com>
2016-05-18Merge branch 'for-chris-4.7' of ↵Chris Mason1-6/+116
git://git.kernel.org/pub/scm/linux/kernel/git/fdmanana/linux into for-linus-4.7 Signed-off-by: Chris Mason <clm@fb.com>
2016-05-16Merge branch 'cleanups-4.7' into for-chris-4.7-20160516David Sterba1-22/+21
2016-05-13Btrfs: fix race between block group relocation and nocow writesFilipe Manana1-0/+53
Relocation of a block group waits for all existing tasks flushing dellaloc, starting direct IO writes and any ordered extents before starting the relocation process. However for direct IO writes that end up doing nocow (inode either has the flag nodatacow set or the write is against a prealloc extent) we have a short time window that allows for a race that makes relocation proceed without waiting for the direct IO write to complete first, resulting in data loss after the relocation finishes. This is illustrated by the following diagram: CPU 1 CPU 2 btrfs_relocate_block_group(bg X) direct IO write starts against an extent in block group X using nocow mode (inode has the nodatacow flag or the write is for a prealloc extent) btrfs_direct_IO() btrfs_get_blocks_direct() --> can_nocow_extent() returns 1 btrfs_inc_block_group_ro(bg X) --> turns block group into RO mode btrfs_wait_ordered_roots() --> returns and does not know about the DIO write happening at CPU 2 (the task there has not created yet an ordered extent) relocate_block_group(bg X) --> rc->stage == MOVE_DATA_EXTENTS find_next_extent() --> returns extent that the DIO write is going to write to relocate_data_extent() relocate_file_extent_cluster() --> reads the extent from disk into pages belonging to the relocation inode and dirties them --> creates DIO ordered extent btrfs_submit_direct() --> submits bio against a location on disk obtained from an extent map before the relocation started btrfs_wait_ordered_range() --> writes all the pages read before to disk (belonging to the relocation inode) relocation finishes bio completes and wrote new data to the old location of the block group So fix this by tracking the number of nocow writers for a block group and make sure relocation waits for that number to go down to 0 before starting to move the extents. The same race can also happen with buffered writes in nocow mode since the patch I recently made titled "Btrfs: don't do unnecessary delalloc flushes when relocating", because we are no longer flushing all delalloc which served as a synchonization mechanism (due to page locking) and ensured the ordered extents for nocow buffered writes were created before we called btrfs_wait_ordered_roots(). The race with direct IO writes in nocow mode existed before that patch (no pages are locked or used during direct IO) and that fixed only races with direct IO writes that do cow. Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: Josef Bacik <jbacik@fb.com>
2016-05-13Btrfs: don't do unnecessary delalloc flushes when relocatingFilipe Manana1-2/+56
Before we start the actual relocation process of a block group, we do calls to flush delalloc of all inodes and then wait for ordered extents to complete. However we do these flush calls just to make sure we don't race with concurrent tasks that have actually already started to run delalloc and have allocated an extent from the block group we want to relocate, right before we set it to readonly mode, but have not yet created the respective ordered extents. The flush calls make us wait for such concurrent tasks because they end up calling filemap_fdatawrite_range() (through btrfs_start_delalloc_roots() -> __start_delalloc_inodes() -> btrfs_alloc_delalloc_work() -> btrfs_run_delalloc_work()) which ends up serializing us with those tasks due to attempts to lock the same pages (and the delalloc flush procedure calls the allocator and creates the ordered extents before unlocking the pages). These flushing calls not only make us waste time (cpu, IO) but also reduce the chances of writing larger extents (applications might be writing to contiguous ranges and we flush before they finish dirtying the whole ranges). So make sure we don't flush delalloc and just wait for concurrent tasks that have already started flushing delalloc and have allocated an extent from the block group we are about to relocate. This change also ends up fixing a race with direct IO writes that makes relocation not wait for direct IO ordered extents. This race is illustrated by the following diagram: CPU 1 CPU 2 btrfs_relocate_block_group(bg X) starts direct IO write, target inode currently has no ordered extents ongoing nor dirty pages (delalloc regions), therefore the root for our inode is not in the list fs_info->ordered_roots btrfs_direct_IO() __blockdev_direct_IO() btrfs_get_blocks_direct() btrfs_lock_extent_direct() locks range in the io tree btrfs_new_extent_direct() btrfs_reserve_extent() --> extent allocated from bg X btrfs_inc_block_group_ro(bg X) btrfs_start_delalloc_roots() __start_delalloc_inodes() --> does nothing, no dealloc ranges in the inode's io tree so the inode's root is not in the list fs_info->delalloc_roots btrfs_wait_ordered_roots() --> does not find the inode's root in the list fs_info->ordered_roots --> ends up not waiting for the direct IO write started by the task at CPU 2 relocate_block_group(rc->stage == MOVE_DATA_EXTENTS) prepare_to_relocate() btrfs_commit_transaction() iterates the extent tree, using its commit root and moves extents into new locations btrfs_add_ordered_extent_dio() --> now a ordered extent is created and added to the list root->ordered_extents and the root added to the list fs_info->ordered_roots --> this is too late and the task at CPU 1 already started the relocation btrfs_commit_transaction() btrfs_finish_ordered_io() btrfs_alloc_reserved_file_extent() --> adds delayed data reference for the extent allocated from bg X relocate_block_group(rc->stage == UPDATE_DATA_PTRS) prepare_to_relocate() btrfs_commit_transaction() --> delayed refs are run, so an extent item for the allocated extent from bg X is added to extent tree --> commit roots are switched, so the next scan in the extent tree will see the extent item sees the extent in the extent tree When this happens the relocation produces the following warning when it finishes: [ 7260.832836] ------------[ cut here ]------------ [ 7260.834653] WARNING: CPU: 5 PID: 6765 at fs/btrfs/relocation.c:4318 btrfs_relocate_block_group+0x245/0x2a1 [btrfs]() [ 7260.838268] Modules linked in: btrfs crc32c_generic xor ppdev raid6_pq psmouse sg acpi_cpufreq evdev i2c_piix4 tpm_tis serio_raw tpm i2c_core pcspkr parport_pc [ 7260.850935] CPU: 5 PID: 6765 Comm: btrfs Not tainted 4.5.0-rc6-btrfs-next-28+ #1 [ 7260.852998] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS by qemu-project.org 04/01/2014 [ 7260.852998] 0000000000000000 ffff88020bf57bc0 ffffffff812648b3 0000000000000000 [ 7260.852998] 0000000000000009 ffff88020bf57bf8 ffffffff81051608 ffffffffa03c1b2d [ 7260.852998] ffff8800b2bbb800 0000000000000000 ffff8800b17bcc58 ffff8800399dd000 [ 7260.852998] Call Trace: [ 7260.852998] [<ffffffff812648b3>] dump_stack+0x67/0x90 [ 7260.852998] [<ffffffff81051608>] warn_slowpath_common+0x99/0xb2 [ 7260.852998] [<ffffffffa03c1b2d>] ? btrfs_relocate_block_group+0x245/0x2a1 [btrfs] [ 7260.852998] [<ffffffff810516d4>] warn_slowpath_null+0x1a/0x1c [ 7260.852998] [<ffffffffa03c1b2d>] btrfs_relocate_block_group+0x245/0x2a1 [btrfs] [ 7260.852998] [<ffffffffa039d9de>] btrfs_relocate_chunk.isra.29+0x66/0xdb [btrfs] [ 7260.852998] [<ffffffffa039f314>] btrfs_balance+0xde1/0xe4e [btrfs] [ 7260.852998] [<ffffffff8127d671>] ? debug_smp_processor_id+0x17/0x19 [ 7260.852998] [<ffffffffa03a9583>] btrfs_ioctl_balance+0x255/0x2d3 [btrfs] [ 7260.852998] [<ffffffffa03ac96a>] btrfs_ioctl+0x11e0/0x1dff [btrfs] [ 7260.852998] [<ffffffff811451df>] ? handle_mm_fault+0x443/0xd63 [ 7260.852998] [<ffffffff81491817>] ? _raw_spin_unlock+0x31/0x44 [ 7260.852998] [<ffffffff8108b36a>] ? arch_local_irq_save+0x9/0xc [ 7260.852998] [<ffffffff811876ab>] vfs_ioctl+0x18/0x34 [ 7260.852998] [<ffffffff81187cb2>] do_vfs_ioctl+0x550/0x5be [ 7260.852998] [<ffffffff81190c30>] ? __fget_light+0x4d/0x71 [ 7260.852998] [<ffffffff81187d77>] SyS_ioctl+0x57/0x79 [ 7260.852998] [<ffffffff81492017>] entry_SYSCALL_64_fastpath+0x12/0x6b [ 7260.893268] ---[ end trace eb7803b24ebab8ad ]--- This is because at the end of the first stage, in relocate_block_group(), we commit the current transaction, which makes delayed refs run, the commit roots are switched and so the second stage will find the extent item that the ordered extent added to the delayed refs. But this extent was not moved (ordered extent completed after first stage finished), so at the end of the relocation our block group item still has a positive used bytes counter, triggering a warning at the end of btrfs_relocate_block_group(). Later on when trying to read the extent contents from disk we hit a BUG_ON() due to the inability to map a block with a logical address that belongs to the block group we relocated and is no longer valid, resulting in the following trace: [ 7344.885290] BTRFS critical (device sdi): unable to find logical 12845056 len 4096 [ 7344.887518] ------------[ cut here ]------------ [ 7344.888431] kernel BUG at fs/btrfs/inode.c:1833! [ 7344.888431] invalid opcode: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC [ 7344.888431] Modules linked in: btrfs crc32c_generic xor ppdev raid6_pq psmouse sg acpi_cpufreq evdev i2c_piix4 tpm_tis serio_raw tpm i2c_core pcspkr parport_pc [ 7344.888431] CPU: 0 PID: 6831 Comm: od Tainted: G W 4.5.0-rc6-btrfs-next-28+ #1 [ 7344.888431] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS by qemu-project.org 04/01/2014 [ 7344.888431] task: ffff880215818600 ti: ffff880204684000 task.ti: ffff880204684000 [ 7344.888431] RIP: 0010:[<ffffffffa037c88c>] [<ffffffffa037c88c>] btrfs_merge_bio_hook+0x54/0x6b [btrfs] [ 7344.888431] RSP: 0018:ffff8802046878f0 EFLAGS: 00010282 [ 7344.888431] RAX: 00000000ffffffea RBX: 0000000000001000 RCX: 0000000000000001 [ 7344.888431] RDX: ffff88023ec0f950 RSI: ffffffff8183b638 RDI: 00000000ffffffff [ 7344.888431] RBP: ffff880204687908 R08: 0000000000000001 R09: 0000000000000000 [ 7344.888431] R10: ffff880204687770 R11: ffffffff82f2d52d R12: 0000000000001000 [ 7344.888431] R13: ffff88021afbfee8 R14: 0000000000006208 R15: ffff88006cd199b0 [ 7344.888431] FS: 00007f1f9e1d6700(0000) GS:ffff88023ec00000(0000) knlGS:0000000000000000 [ 7344.888431] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 7344.888431] CR2: 00007f1f9dc8cb60 CR3: 000000023e3b6000 CR4: 00000000000006f0 [ 7344.888431] Stack: [ 7344.888431] 0000000000001000 0000000000001000 ffff880204687b98 ffff880204687950 [ 7344.888431] ffffffffa0395c8f ffffea0004d64d48 0000000000000000 0000000000001000 [ 7344.888431] ffffea0004d64d48 0000000000001000 0000000000000000 0000000000000000 [ 7344.888431] Call Trace: [ 7344.888431] [<ffffffffa0395c8f>] submit_extent_page+0xf5/0x16f [btrfs] [ 7344.888431] [<ffffffffa03970ac>] __do_readpage+0x4a0/0x4f1 [btrfs] [ 7344.888431] [<ffffffffa039680d>] ? btrfs_create_repair_bio+0xcb/0xcb [btrfs] [ 7344.888431] [<ffffffffa037eeb4>] ? btrfs_writepage_start_hook+0xbc/0xbc [btrfs] [ 7344.888431] [<ffffffff8108df55>] ? trace_hardirqs_on+0xd/0xf [ 7344.888431] [<ffffffffa039728c>] __do_contiguous_readpages.constprop.26+0xc2/0xe4 [btrfs] [ 7344.888431] [<ffffffffa037eeb4>] ? btrfs_writepage_start_hook+0xbc/0xbc [btrfs] [ 7344.888431] [<ffffffffa039739b>] __extent_readpages.constprop.25+0xed/0x100 [btrfs] [ 7344.888431] [<ffffffff81129d24>] ? lru_cache_add+0xe/0x10 [ 7344.888431] [<ffffffffa0397ea8>] extent_readpages+0x160/0x1aa [btrfs] [ 7344.888431] [<ffffffffa037eeb4>] ? btrfs_writepage_start_hook+0xbc/0xbc [btrfs] [ 7344.888431] [<ffffffff8115daad>] ? alloc_pages_current+0xa9/0xcd [ 7344.888431] [<ffffffffa037cdc9>] btrfs_readpages+0x1f/0x21 [btrfs] [ 7344.888431] [<ffffffff81128316>] __do_page_cache_readahead+0x168/0x1fc [ 7344.888431] [<ffffffff811285a0>] ondemand_readahead+0x1f6/0x207 [ 7344.888431] [<ffffffff811285a0>] ? ondemand_readahead+0x1f6/0x207 [ 7344.888431] [<ffffffff8111cf34>] ? pagecache_get_page+0x2b/0x154 [ 7344.888431] [<ffffffff8112870e>] page_cache_sync_readahead+0x3d/0x3f [ 7344.888431] [<ffffffff8111dbf7>] generic_file_read_iter+0x197/0x4e1 [ 7344.888431] [<ffffffff8117773a>] __vfs_read+0x79/0x9d [ 7344.888431] [<ffffffff81178050>] vfs_read+0x8f/0xd2 [ 7344.888431] [<ffffffff81178a38>] SyS_read+0x50/0x7e [ 7344.888431] [<ffffffff81492017>] entry_SYSCALL_64_fastpath+0x12/0x6b [ 7344.888431] Code: 8d 4d e8 45 31 c9 45 31 c0 48 8b 00 48 c1 e2 09 48 8b 80 80 fc ff ff 4c 89 65 e8 48 8b b8 f0 01 00 00 e8 1d 42 02 00 85 c0 79 02 <0f> 0b 4c 0 [ 7344.888431] RIP [<ffffffffa037c88c>] btrfs_merge_bio_hook+0x54/0x6b [btrfs] [ 7344.888431] RSP <ffff8802046878f0> [ 7344.970544] ---[ end trace eb7803b24ebab8ae ]--- Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: Josef Bacik <jbacik@fb.com> Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
2016-05-13Btrfs: don't wait for unrelated IO to finish before relocationFilipe Manana1-4/+7
Before the relocation process of a block group starts, it sets the block group to readonly mode, then flushes all delalloc writes and then finally it waits for all ordered extents to complete. This last step includes waiting for ordered extents destinated at extents allocated in other block groups, making us waste unecessary time. So improve this by waiting only for ordered extents that fall into the block group's range. Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: Josef Bacik <jbacik@fb.com> Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
2016-05-09btrfs: fix int32 overflow in shrink_delalloc().Adam Borowski1-1/+1
UBSAN: Undefined behaviour in fs/btrfs/extent-tree.c:4623:21 signed integer overflow: 10808 * 262144 cannot be represented in type 'int [8]' If 8192<=items<16384, we request a writeback of an insane number of pages which is benign (everything will be written). But if items>=16384, the space reservation won't be enough. Signed-off-by: Adam Borowski <kilobyte@angband.pl> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2016-04-29btrfs: sink gfp parameter to set_extent_newDavid Sterba1-1/+1
Single caller passes GFP_NOFS. Signed-off-by: David Sterba <dsterba@suse.com>
2016-04-29btrfs: sink gfp parameter to clear_extent_dirtyDavid Sterba1-1/+1
Callers pass GFP_NOFS. No need to pass the flags around. Signed-off-by: David Sterba <dsterba@suse.com>
2016-04-29btrfs: sink gfp parameter to clear_extent_bitsDavid Sterba1-4/+4
Callers pass GFP_NOFS and GFP_KERNEL. No need to pass the flags around. Signed-off-by: David Sterba <dsterba@suse.com>
2016-04-29btrfs: sink gfp parameter to set_extent_bitsDavid Sterba1-2/+2
All callers pass GFP_NOFS. Signed-off-by: David Sterba <dsterba@suse.com>
2016-04-28Btrfs: Refactor btrfs_lock_cluster() to kill compiler warningGeert Uytterhoeven1-21/+20
fs/btrfs/extent-tree.c: In function ‘btrfs_lock_cluster’: fs/btrfs/extent-tree.c:6399: warning: ‘used_bg’ may be used uninitialized in this function - Replace "again: ... goto again;" by standard C "while (1) { ... }", - Move block not processed during the first iteration of the loop to the end of the loop, which allows to kill the "locked" variable, Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Reviewed-and-Tested-by: Miao Xie <miaox@cn.fujitsu.com> [ the compilation warning has been fixed by other patch, now we want to clean up the function ] Signed-off-by: David Sterba <dsterba@suse.com>
2016-04-28btrfs: rename btrfs_std_error to btrfs_handle_fs_errorAnand Jain1-1/+1
btrfs_std_error() handles errors, puts FS into readonly mode (as of now). So its good idea to rename it to btrfs_handle_fs_error(). Signed-off-by: Anand Jain <anand.jain@oracle.com> Reviewed-by: David Sterba <dsterba@suse.com> [ edit changelog ] Signed-off-by: David Sterba <dsterba@suse.com>
2016-04-09Merge branch 'for-linus-4.6' of ↵Linus Torvalds1-2/+19
git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs Pull btrfs fixes from Chris Mason: "These are bug fixes, including a really old fsync bug, and a few trace points to help us track down problems in the quota code" * 'for-linus-4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: Btrfs: fix file/data loss caused by fsync after rename and new inode btrfs: Reset IO error counters before start of device replacing btrfs: Add qgroup tracing Btrfs: don't use src fd for printk btrfs: fallback to vmalloc in btrfs_compare_tree btrfs: handle non-fatal errors in btrfs_qgroup_inherit() btrfs: Output more info for enospc_debug mount option Btrfs: fix invalid reference in replace_path Btrfs: Improve FL_KEEP_SIZE handling in fallocate
2016-04-04mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macrosKirill A. Shutemov1-2/+2
PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time ago with promise that one day it will be possible to implement page cache with bigger chunks than PAGE_SIZE. This promise never materialized. And unlikely will. We have many places where PAGE_CACHE_SIZE assumed to be equal to PAGE_SIZE. And it's constant source of confusion on whether PAGE_CACHE_* or PAGE_* constant should be used in a particular case, especially on the border between fs and mm. Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much breakage to be doable. Let's stop pretending that pages in page cache are special. They are not. The changes are pretty straight-forward: - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN}; - page_cache_get() -> get_page(); - page_cache_release() -> put_page(); This patch contains automated changes generated with coccinelle using script below. For some reason, coccinelle doesn't patch header files. I've called spatch for them manually. The only adjustment after coccinelle is revert of changes to PAGE_CAHCE_ALIGN definition: we are going to drop it later. There are few places in the code where coccinelle didn't reach. I'll fix them manually in a separate patch. Comments and documentation also will be addressed with the separate patch. virtual patch @@ expression E; @@ - E << (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ expression E; @@ - E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ @@ - PAGE_CACHE_SHIFT + PAGE_SHIFT @@ @@ - PAGE_CACHE_SIZE + PAGE_SIZE @@ @@ - PAGE_CACHE_MASK + PAGE_MASK @@ expression E; @@ - PAGE_CACHE_ALIGN(E) + PAGE_ALIGN(E) @@ expression E; @@ - page_cache_get(E) + get_page(E) @@ expression E; @@ - page_cache_release(E) + put_page(E) Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-04btrfs: Output more info for enospc_debug mount optionQu Wenruo1-2/+19
As one user in mail list report reproducible balance ENOSPC error, it's better to add more debug info for enospc_debug mount option. Reported-by: Marc Haber <mh+linux-btrfs@zugschlus.de> Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com> Signed-off-by: David Sterba <dsterba@suse.com>
2016-03-14btrfs: Fix misspellings in comments.Adam Buchbinder1-1/+1
Signed-off-by: Adam Buchbinder <adam.buchbinder@gmail.com> Signed-off-by: David Sterba <dsterba@suse.com>
2016-02-26Merge branch 'cleanups-4.6' into for-chris-4.6David Sterba1-1/+1
2016-02-18btrfs: fix build warningSudip Mukherjee1-1/+1
We were getting build warning about: fs/btrfs/extent-tree.c:7021:34: warning: ‘used_bg’ may be used uninitialized in this function It is not a valid warning as used_bg is never used uninitilized since locked is initially false so we can never be in the section where 'used_bg' is used. But gcc is not able to understand that and we can initialize it while declaring to silence the warning. Signed-off-by: Sudip Mukherjee <sudip@vectorindia.org> Signed-off-by: David Sterba <dsterba@suse.com>
2016-02-18Btrfs: check reserved when deciding to background flushJosef Bacik1-1/+1
We will sometimes start background flushing the various enospc related things (delayed nodes, delalloc, etc) if we are getting close to reserving all of our available space. We don't want to do this however when we are actually using this space as it causes unneeded thrashing. We currently try to do this by checking bytes_used >= thresh, but bytes_used is only part of the equation, we need to use bytes_reserved as well as this represents space that is very likely to become bytes_used in the future. My tracing tool will keep count of the number of times we kick off the async flusher, the following are counts for the entire run of generic/027 No Patch Patch avg: 5385 5009 median: 5500 4916 We skewed lower than the average with my patch and higher than the average with the patch, overall it cuts the flushing from anywhere from 5-10%, which in the case of actual ENOSPC is quite helpful. Thanks, Signed-off-by: Josef Bacik <jbacik@fb.com> Reviewed-by: Liu Bo <bo.li.liu@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
2016-02-18Btrfs: change how we update the global block rsvJosef Bacik1-14/+20
I'm writing a tool to visualize the enospc system in order to help debug enospc bugs and I found weird data and ran it down to when we update the global block rsv. We add all of the remaining free space to the block rsv, do a trace event, then remove the extra and do another trace event. This makes my visualization look silly and is unintuitive code as well. Fix this stuff to only add the amount we are missing, or free the amount we are missing. This is less clean to read but more explicit in what it is doing, as well as only emitting events for values that make sense. Thanks, Signed-off-by: Josef Bacik <jbacik@fb.com> Signed-off-by: David Sterba <dsterba@suse.com>
2016-01-20btrfs: Fix no_space in write and rm loopZhao Lei1-1/+3
I see no_space in v4.4-rc1 again in xfstests generic/102. It happened randomly in some node only. (one of 4 phy-node, and a kvm with non-virtio block driver) By bisect, we can found the first-bad is: commit bdced438acd8 ("block: setup bi_phys_segments after splitting")' But above patch only triggered the bug by making bio operation faster(or slower). Main reason is in our space_allocating code, we need to commit page writeback before wait it complish, this patch fixed above bug. BTW, there is another reason for generic/102 fail, caused by disable default mixed-blockgroup, I'll fix it in xfstests. Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com> Signed-off-by: Chris Mason <clm@fb.com>
2016-01-20btrfs: merge functions for wait snapshot creationZhao Lei1-0/+20
wait_for_snapshot_creation() is in same group with oher two: btrfs_start_write_no_snapshoting() btrfs_end_write_no_snapshoting() Rename wait_for_snapshot_creation() and move it into same place with other two. Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com> Signed-off-by: Chris Mason <clm@fb.com>
2016-01-20Btrfs: fix deadlock running delayed iputs at transaction commit timeFilipe Manana1-4/+5
While running a stress test I ran into a deadlock when running the delayed iputs at transaction time, which produced the following report and trace: [ 886.399989] ============================================= [ 886.400871] [ INFO: possible recursive locking detected ] [ 886.401663] 4.4.0-rc6-btrfs-next-18+ #1 Not tainted [ 886.402384] --------------------------------------------- [ 886.403182] fio/8277 is trying to acquire lock: [ 886.403568] (&fs_info->delayed_iput_sem){++++..}, at: [<ffffffffa0538823>] btrfs_run_delayed_iputs+0x36/0xbf [btrfs] [ 886.403568] [ 886.403568] but task is already holding lock: [ 886.403568] (&fs_info->delayed_iput_sem){++++..}, at: [<ffffffffa0538823>] btrfs_run_delayed_iputs+0x36/0xbf [btrfs] [ 886.403568] [ 886.403568] other info that might help us debug this: [ 886.403568] Possible unsafe locking scenario: [ 886.403568] [ 886.403568] CPU0 [ 886.403568] ---- [ 886.403568] lock(&fs_info->delayed_iput_sem); [ 886.403568] lock(&fs_info->delayed_iput_sem); [ 886.403568] [ 886.403568] *** DEADLOCK *** [ 886.403568] [ 886.403568] May be due to missing lock nesting notation [ 886.403568] [ 886.403568] 3 locks held by fio/8277: [ 886.403568] #0: (sb_writers#11){.+.+.+}, at: [<ffffffff81174c4c>] __sb_start_write+0x5f/0xb0 [ 886.403568] #1: (&sb->s_type->i_mutex_key#15){+.+.+.}, at: [<ffffffffa054620d>] btrfs_file_write_iter+0x73/0x408 [btrfs] [ 886.403568] #2: (&fs_info->delayed_iput_sem){++++..}, at: [<ffffffffa0538823>] btrfs_run_delayed_iputs+0x36/0xbf [btrfs] [ 886.403568] [ 886.403568] stack backtrace: [ 886.403568] CPU: 6 PID: 8277 Comm: fio Not tainted 4.4.0-rc6-btrfs-next-18+ #1 [ 886.403568] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS by qemu-project.org 04/01/2014 [ 886.403568] 0000000000000000 ffff88009f80f770 ffffffff8125d4fd ffffffff82af1fc0 [ 886.403568] ffff88009f80f830 ffffffff8108e5f9 0000000200000000 ffff88009fd92290 [ 886.403568] 0000000000000000 ffffffff82af1fc0 ffffffff829cfb01 00042b216d008804 [ 886.403568] Call Trace: [ 886.403568] [<ffffffff8125d4fd>] dump_stack+0x4e/0x79 [ 886.403568] [<ffffffff8108e5f9>] __lock_acquire+0xd42/0xf0b [ 886.403568] [<ffffffff810c22db>] ? __module_address+0xdf/0x108 [ 886.403568] [<ffffffff8108eb77>] lock_acquire+0x10d/0x194 [ 886.403568] [<ffffffff8108eb77>] ? lock_acquire+0x10d/0x194 [ 886.403568] [<ffffffffa0538823>] ? btrfs_run_delayed_iputs+0x36/0xbf [btrfs] [ 886.489542] [<ffffffff8148556b>] down_read+0x3e/0x4d [ 886.489542] [<ffffffffa0538823>] ? btrfs_run_delayed_iputs+0x36/0xbf [btrfs] [ 886.489542] [<ffffffffa0538823>] btrfs_run_delayed_iputs+0x36/0xbf [btrfs] [ 886.489542] [<ffffffffa0533953>] btrfs_commit_transaction+0x8f5/0x96e [btrfs] [ 886.489542] [<ffffffffa0521d7a>] flush_space+0x435/0x44a [btrfs] [ 886.489542] [<ffffffffa052218b>] ? reserve_metadata_bytes+0x26a/0x384 [btrfs] [ 886.489542] [<ffffffffa05221ae>] reserve_metadata_bytes+0x28d/0x384 [btrfs] [ 886.489542] [<ffffffffa052256c>] ? btrfs_block_rsv_refill+0x58/0x96 [btrfs] [ 886.489542] [<ffffffffa0522584>] btrfs_block_rsv_refill+0x70/0x96 [btrfs] [ 886.489542] [<ffffffffa053d747>] btrfs_evict_inode+0x394/0x55a [btrfs] [ 886.489542] [<ffffffff81188e31>] evict+0xa7/0x15c [ 886.489542] [<ffffffff81189878>] iput+0x1d3/0x266 [ 886.489542] [<ffffffffa053887c>] btrfs_run_delayed_iputs+0x8f/0xbf [btrfs] [ 886.489542] [<ffffffffa0533953>] btrfs_commit_transaction+0x8f5/0x96e [btrfs] [ 886.489542] [<ffffffff81085096>] ? signal_pending_state+0x31/0x31 [ 886.489542] [<ffffffffa0521191>] btrfs_alloc_data_chunk_ondemand+0x1d7/0x288 [btrfs] [ 886.489542] [<ffffffffa0521282>] btrfs_check_data_free_space+0x40/0x59 [btrfs] [ 886.489542] [<ffffffffa05228f5>] btrfs_delalloc_reserve_space+0x1e/0x4e [btrfs] [ 886.489542] [<ffffffffa053620a>] btrfs_direct_IO+0x10c/0x27e [btrfs] [ 886.489542] [<ffffffff8111d9a1>] generic_file_direct_write+0xb3/0x128 [ 886.489542] [<ffffffffa05463c3>] btrfs_file_write_iter+0x229/0x408 [btrfs] [ 886.489542] [<ffffffff8108ae38>] ? __lock_is_held+0x38/0x50 [ 886.489542] [<ffffffff8117279e>] __vfs_write+0x7c/0xa5 [ 886.489542] [<ffffffff81172cda>] vfs_write+0xa0/0xe4 [ 886.489542] [<ffffffff811734cc>] SyS_write+0x50/0x7e [ 886.489542] [<ffffffff814872d7>] entry_SYSCALL_64_fastpath+0x12/0x6f [ 1081.852335] INFO: task fio:8244 blocked for more than 120 seconds. [ 1081.854348] Not tainted 4.4.0-rc6-btrfs-next-18+ #1 [ 1081.857560] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 1081.863227] fio D ffff880213f9bb28 0 8244 8240 0x00000000 [ 1081.868719] ffff880213f9bb28 00ffffff810fc6b0 ffffffff0000000a ffff88023ed55240 [ 1081.872499] ffff880206b5d400 ffff880213f9c000 ffff88020a4d5318 ffff880206b5d400 [ 1081.876834] ffffffff00000001 ffff880206b5d400 ffff880213f9bb40 ffffffff81482ba4 [ 1081.880782] Call Trace: [ 1081.881793] [<ffffffff81482ba4>] schedule+0x7f/0x97 [ 1081.883340] [<ffffffff81485eb5>] rwsem_down_write_failed+0x2d5/0x325 [ 1081.895525] [<ffffffff8108d48d>] ? trace_hardirqs_on_caller+0x16/0x1ab [ 1081.897419] [<ffffffff81269723>] call_rwsem_down_write_failed+0x13/0x20 [ 1081.899251] [<ffffffff81269723>] ? call_rwsem_down_write_failed+0x13/0x20 [ 1081.901063] [<ffffffff81089fae>] ? __down_write_nested.isra.0+0x1f/0x21 [ 1081.902365] [<ffffffff814855bd>] down_write+0x43/0x57 [ 1081.903846] [<ffffffffa05211b0>] ? btrfs_alloc_data_chunk_ondemand+0x1f6/0x288 [btrfs] [ 1081.906078] [<ffffffffa05211b0>] btrfs_alloc_data_chunk_ondemand+0x1f6/0x288 [btrfs] [ 1081.908846] [<ffffffff8108d461>] ? mark_held_locks+0x56/0x6c [ 1081.910409] [<ffffffffa0521282>] btrfs_check_data_free_space+0x40/0x59 [btrfs] [ 1081.912482] [<ffffffffa05228f5>] btrfs_delalloc_reserve_space+0x1e/0x4e [btrfs] [ 1081.914597] [<ffffffffa053620a>] btrfs_direct_IO+0x10c/0x27e [btrfs] [ 1081.919037] [<ffffffff8111d9a1>] generic_file_direct_write+0xb3/0x128 [ 1081.920754] [<ffffffffa05463c3>] btrfs_file_write_iter+0x229/0x408 [btrfs] [ 1081.922496] [<ffffffff8108ae38>] ? __lock_is_held+0x38/0x50 [ 1081.923922] [<ffffffff8117279e>] __vfs_write+0x7c/0xa5 [ 1081.925275] [<ffffffff81172cda>] vfs_write+0xa0/0xe4 [ 1081.926584] [<ffffffff811734cc>] SyS_write+0x50/0x7e [ 1081.927968] [<ffffffff814872d7>] entry_SYSCALL_64_fastpath+0x12/0x6f [ 1081.985293] INFO: lockdep is turned off. [ 1081.986132] INFO: task fio:8249 blocked for more than 120 seconds. [ 1081.987434] Not tainted 4.4.0-rc6-btrfs-next-18+ #1 [ 1081.988534] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 1081.990147] fio D ffff880218febbb8 0 8249 8240 0x00000000 [ 1081.991626] ffff880218febbb8 00ffffff81486b8e ffff88020000000b ffff88023ed75240 [ 1081.993258] ffff8802120a9a00 ffff880218fec000 ffff88020a4d5318 ffff8802120a9a00 [ 1081.994850] ffffffff00000001 ffff8802120a9a00 ffff880218febbd0 ffffffff81482ba4 [ 1081.996485] Call Trace: [ 1081.997037] [<ffffffff81482ba4>] schedule+0x7f/0x97 [ 1081.998017] [<ffffffff81485eb5>] rwsem_down_write_failed+0x2d5/0x325 [ 1081.999241] [<ffffffff810852a5>] ? finish_wait+0x6d/0x76 [ 1082.000306] [<ffffffff81269723>] call_rwsem_down_write_failed+0x13/0x20 [ 1082.001533] [<ffffffff81269723>] ? call_rwsem_down_write_failed+0x13/0x20 [ 1082.002776] [<ffffffff81089fae>] ? __down_write_nested.isra.0+0x1f/0x21 [ 1082.003995] [<ffffffff814855bd>] down_write+0x43/0x57 [ 1082.005000] [<ffffffffa05211b0>] ? btrfs_alloc_data_chunk_ondemand+0x1f6/0x288 [btrfs] [ 1082.007403] [<ffffffffa05211b0>] btrfs_alloc_data_chunk_ondemand+0x1f6/0x288 [btrfs] [ 1082.008988] [<ffffffffa0545064>] btrfs_fallocate+0x7c1/0xc2f [btrfs] [ 1082.010193] [<ffffffff8108a1ba>] ? percpu_down_read+0x4e/0x77 [ 1082.011280] [<ffffffff81174c4c>] ? __sb_start_write+0x5f/0xb0 [ 1082.012265] [<ffffffff81174c4c>] ? __sb_start_write+0x5f/0xb0 [ 1082.013021] [<ffffffff811712e4>] vfs_fallocate+0x170/0x1ff [ 1082.013738] [<ffffffff81181ebb>] ioctl_preallocate+0x89/0x9b [ 1082.014778] [<ffffffff811822d7>] do_vfs_ioctl+0x40a/0x4ea [ 1082.015778] [<ffffffff81176ea7>] ? SYSC_newfstat+0x25/0x2e [ 1082.016806] [<ffffffff8118b4de>] ? __fget_light+0x4d/0x71 [ 1082.017789] [<ffffffff8118240e>] SyS_ioctl+0x57/0x79 [ 1082.018706] [<ffffffff814872d7>] entry_SYSCALL_64_fastpath+0x12/0x6f This happens because we can recursively acquire the semaphore fs_info->delayed_iput_sem when attempting to allocate space to satisfy a file write request as shown in the first trace above - when committing a transaction we acquire (down_read) the semaphore before running the delayed iputs, and when running a delayed iput() we can end up calling an inode's eviction handler, which in turn commits another transaction and attempts to acquire (down_read) again the semaphore to run more delayed iput operations. This results in a deadlock because if a task acquires multiple times a semaphore it should invoke down_read_nested() with a different lockdep class for each level of recursion. Fix this by simplifying the implementation and use a mutex instead that is acquired by the cleaner kthread before it runs the delayed iputs instead of always acquiring a semaphore before delayed references are run from anywhere. Fixes: d7c151717a1e (btrfs: Fix NO_SPACE bug caused by delayed-iput) Cc: stable@vger.kernel.org # 4.1+ Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Chris Mason <clm@fb.com>
2016-01-20Merge branch 'misc-cleanups-4.5' of ↵Chris Mason1-2/+2
git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux into for-linus-4.5
2016-01-15Btrfs: clean up an error code in btrfs_init_space_info()Dan Carpenter1-1/+1
If we return 1 here, then the caller treats it as an error and returns -EINVAL. It causes a static checker warning to treat positive returns as an error. Fixes: 1aba86d67f34 ('Btrfs: fix easily get into ENOSPC in mixed case') Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
2016-01-15btrfs: cleanup, stop casting for extent_map->lookup everywhereJeff Mahoney1-1/+1
Overloading extent_map->bdev to struct map_lookup * might have started out as a means to an end, but it's a pattern that's used all over the place now. Let's get rid of the casting and just add a union instead. Signed-off-by: Jeff Mahoney <jeffm@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2016-01-11Merge branch 'for-chris-4.5' of ↵Chris Mason1-0/+19
git://git.kernel.org/pub/scm/linux/kernel/git/fdmanana/linux into for-linus-4.5 Signed-off-by: Chris Mason <clm@fb.com>
2016-01-11Merge branch 'misc-cleanups-4.5' of ↵Chris Mason1-15/+12
git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux into for-linus-4.5 Signed-off-by: Chris Mason <clm@fb.com>
2016-01-11Merge branch 'misc-for-4.5' of ↵Chris Mason1-15/+12
git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux into for-linus-4.5
2016-01-07btrfs: cleanup, use enum values for btrfs_path readaDavid Sterba1-6/+6
Replace the integers by enums for better readability. The value 2 does not have any meaning since a717531942f488209dded30f6bc648167bcefa72 "Btrfs: do less aggressive btree readahead" (2009-01-22). Signed-off-by: David Sterba <dsterba@suse.com>
2016-01-07Btrfs: use linux/sizes.h to represent constantsByongho Lee1-16/+13
We use many constants to represent size and offset value. And to make code readable we use '256 * 1024 * 1024' instead of '268435456' to represent '256MB'. However we can make far more readable with 'SZ_256MB' which is defined in the 'linux/sizes.h'. So this patch replaces 'xxx * 1024 * 1024' kind of expression with single 'SZ_xxxMB' if 'xxx' is a power of 2 then 'xxx * SZ_1M' if 'xxx' is not a power of 2. And I haven't touched to '4096' & '8192' because it's more intuitive than 'SZ_4KB' & 'SZ_8KB'. Signed-off-by: Byongho Lee <bhlee.kernel@gmail.com> Signed-off-by: David Sterba <dsterba@suse.com>
2016-01-07btrfs: better packing of btrfs_delayed_extent_opDavid Sterba1-9/+6
btrfs_delayed_extent_op can be packed in a better way, it's 40 bytes now and has 8 unused bytes. Reducing the level type to u8 makes it possible to squeeze it to the padding byte after key. The bitfields were switched to bool as there's space to store the full byte without increasing the whole structure, besides that the generated assembly is smaller. struct btrfs_delayed_extent_op { struct btrfs_disk_key key; /* 0 17 */ u8 level; /* 17 1 */ bool update_key; /* 18 1 */ bool update_flags; /* 19 1 */ bool is_data; /* 20 1 */ /* XXX 3 bytes hole, try to pack */ u64 flags_to_set; /* 24 8 */ /* size: 32, cachelines: 1, members: 6 */ /* sum members: 29, holes: 1, sum holes: 3 */ /* last cacheline: 32 bytes */ }; The final size is 32 bytes which gives +26 object per slab page. text data bss dec hex filename 938811 43670 23144 1005625 f5839 fs/btrfs/btrfs.ko.before 938747 43670 23144 1005561 f57f9 fs/btrfs/btrfs.ko.after Signed-off-by: David Sterba <dsterba@suse.com>
2015-12-30Btrfs: fix race between free space endio workers and space cache writeoutFilipe Manana1-0/+19
While running a stress test I ran into the following trace/transaction abort: [471626.672243] ------------[ cut here ]------------ [471626.673322] WARNING: CPU: 9 PID: 19107 at fs/btrfs/extent-tree.c:3740 btrfs_write_dirty_block_groups+0x17c/0x214 [btrfs]() [471626.675492] BTRFS: Transaction aborted (error -2) [471626.676748] Modules linked in: btrfs dm_flakey dm_mod crc32c_generic xor raid6_pq nfsd auth_rpcgss oid_registry nfs_acl nfs lockd grace fscache sunrpc loop fuse parport_pc i2c_piix [471626.688802] CPU: 14 PID: 19107 Comm: fsstress Tainted: G W 4.3.0-rc5-btrfs-next-17+ #1 [471626.690148] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.8.1-0-g4adadbd-20150316_085822-nilsson.home.kraxel.org 04/01/2014 [471626.691901] 0000000000000000 ffff880016037cf0 ffffffff812566f4 ffff880016037d38 [471626.695009] ffff880016037d28 ffffffff8104d0a6 ffffffffa040c84e 00000000fffffffe [471626.697490] ffff88011fe855f8 ffff88000c484cb0 ffff88000d195000 ffff880016037d90 [471626.699201] Call Trace: [471626.699804] [<ffffffff812566f4>] dump_stack+0x4e/0x79 [471626.701049] [<ffffffff8104d0a6>] warn_slowpath_common+0x9f/0xb8 [471626.702542] [<ffffffffa040c84e>] ? btrfs_write_dirty_block_groups+0x17c/0x214 [btrfs] [471626.704326] [<ffffffff8104d107>] warn_slowpath_fmt+0x48/0x50 [471626.705636] [<ffffffffa0403717>] ? write_one_cache_group.isra.32+0x77/0x82 [btrfs] [471626.707048] [<ffffffffa040c84e>] btrfs_write_dirty_block_groups+0x17c/0x214 [btrfs] [471626.708616] [<ffffffffa048a50a>] commit_cowonly_roots+0x1d7/0x25a [btrfs] [471626.709950] [<ffffffffa041e34a>] btrfs_commit_transaction+0x4c4/0x991 [btrfs] [471626.711286] [<ffffffff81081c61>] ? signal_pending_state+0x31/0x31 [471626.712611] [<ffffffffa03f6df4>] btrfs_sync_fs+0x145/0x1ad [btrfs] [471626.715610] [<ffffffff811962a2>] ? SyS_tee+0x226/0x226 [471626.716718] [<ffffffff811962c2>] sync_fs_one_sb+0x20/0x22 [471626.717672] [<ffffffff8116fc01>] iterate_supers+0x75/0xc2 [471626.718800] [<ffffffff8119669a>] sys_sync+0x52/0x80 [471626.719990] [<ffffffff8147cd97>] entry_SYSCALL_64_fastpath+0x12/0x6f [471626.721835] ---[ end trace baf57f43d76693f4 ]--- [471626.722954] BTRFS: error (device sdc) in btrfs_write_dirty_block_groups:3740: errno=-2 No such entry This is a very rare situation and it happened due to a race between a free space endio worker and writing the space caches for dirty block groups at a transaction's commit critical section. The steps leading to this are: 1) A task calls btrfs_commit_transaction() and starts the writeout of the space caches for all currently dirty block groups (i.e. it calls btrfs_start_dirty_block_groups()); 2) The previous step starts writeback for space caches; 3) When the writeback finishes it queues jobs for free space endio work queue (fs_info->endio_freespace_worker) that execute btrfs_finish_ordered_io(); 4) The task committing the transaction sets the transaction's state to TRANS_STATE_COMMIT_DOING and shortly after calls btrfs_write_dirty_block_groups(); 5) A free space endio job joins the transaction, through btrfs_join_transaction_nolock(), and updates a free space inode item in the root tree through btrfs_update_inode_fallback(); 6) Updating the free space inode item resulted in COWing one or more nodes/leaves of the root tree, and that resulted in creating a new metadata block group, which gets added to the transaction's list of dirty block groups (this is a very rare case); 7) The free space endio job has not released yet its transaction handle at this point, so the new metadata block group was not yet fully created (didn't go through btrfs_create_pending_block_groups() yet); 8) The transaction commit task sees the new metadata block group in the transaction's list of dirty block groups and processes it. When it attempts to update the block group's block group item in the extent tree, through write_one_cache_group(), it isn't able to find it and aborts the transaction with error -ENOENT - this is because the free space endio job hasn't yet released its transaction handle (which calls btrfs_create_pending_block_groups()) and therefore the block group item was not yet added to the extent tree. Fix this waiting for free space endio jobs if we fail to find a block group item in the extent tree and then retry once updating the block group item. Signed-off-by: Filipe Manana <fdmanana@suse.com>
2015-12-30btrfs: don't run delayed references while we are creating the free space treeChris Mason1-0/+3
This is a short term solution to make sure btrfs_run_delayed_refs() doesn't change the extent tree while we are scanning it to create the free space tree. Longer term we need to synchronize scanning the block groups one by one, similar to what happens during a balance. Signed-off-by: Chris Mason <clm@fb.com>
2015-12-30btrfs: fix compiling with CONFIG_BTRFS_DEBUG enabled.Chris Mason1-0/+2
Merging in the free space tree deleted a variable needed when CONFIG_BTRFS_DEBUG=y Signed-off-by: Chris Mason <clm@fb.com>
2015-12-24Merge branch 'freespace-4.5' into for-linus-4.5Chris Mason1-30/+71
2015-12-24Merge branch 'for-chris-4.5' of ↵Chris Mason1-2/+17
git://git.kernel.org/pub/scm/linux/kernel/git/fdmanana/linux into for-linus-4.5
2015-12-24Merge branch 'cleanup/misc-simplify' of ↵Chris Mason1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux into for-linus-4.5
2015-12-21Btrfs: fix unprotected list operations at btrfs_write_dirty_block_groupsFilipe Manana1-2/+17
We call btrfs_write_dirty_block_groups() in the critical section of a transaction's commit, when no other tasks can join the transaction and add more block groups to the transaction's list of dirty block groups, so we not taking the dirty block groups spinlock when checking for the list's emptyness, grabbing its first element or deleting elements from it. However there's a special and rare case where we can have a concurrent task adding elements to this list. We trigger writeback for space caches before at btrfs_start_dirty_block_groups() and in past iterations of the loop at btrfs_write_dirty_block_groups(), this means that when the writeback finishes (which happens asynchronously) it creates a task for the endio free space work queue that executes btrfs_finish_ordered_io() - this function is able to join the transaction, through btrfs_join_transaction_nolock(), and update the free space cache's inode item in the root tree, which can result in COWing nodes of this tree and therefore allocation of a new block group can happen, which gets added to the transaction's list of dirty block groups while the transaction commit task is operating on it concurrently. So fix this by taking the dirty block groups spinlock before doing operations on the dirty block groups list at btrfs_write_dirty_block_groups(). Signed-off-by: Filipe Manana <fdmanana@suse.com>
2015-12-18Merge branch 'freespace-tree' into for-linus-4.5Chris Mason1-30/+71
Signed-off-by: Chris Mason <clm@fb.com>
2015-12-17Btrfs: wire up the free space tree to the extent treeOmar Sandoval1-3/+33
The free space tree is updated in tandem with the extent tree. There are only a handful of places where we need to hook in: 1. Block group creation 2. Block group deletion 3. Delayed refs (extent creation and deletion) 4. Block group caching Signed-off-by: Omar Sandoval <osandov@fb.com> Signed-off-by: Chris Mason <clm@fb.com>
generated by cgit v1.2.3 (git 2.39.0) at 2024-12-27 01:03:39 +0300