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71 Commits
| Author | SHA1 | Message | Date | |
|---|---|---|---|---|
Nikolay Borisov
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b06359a325 |
btrfs: make btrfs_cont_expand take btrfs_inode
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> |
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Nikolay Borisov
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9a56fcd15a |
btrfs: make btrfs_update_inode take btrfs_inode
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> |
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Nikolay Borisov
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76aea53796 |
btrfs: make btrfs_inode_safe_disk_i_size_write take btrfs_inode
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> |
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Filipe Manana
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2766ff6176 |
btrfs: update the number of bytes used by an inode atomically
There are several occasions where we do not update the inode's number of used bytes atomically, resulting in a concurrent stat(2) syscall to report a value of used blocks that does not correspond to a valid value, that is, a value that does not match neither what we had before the operation nor what we get after the operation completes. In extreme cases it can result in stat(2) reporting zero used blocks, which can cause problems for some userspace tools where they can consider a file with a non-zero size and zero used blocks as completely sparse and skip reading data, as reported/discussed a long time ago in some threads like the following: https://lists.gnu.org/archive/html/bug-tar/2016-07/msg00001.html The cases where this can happen are the following: -> Case 1 If we do a write (buffered or direct IO) against a file region for which there is already an allocated extent (or multiple extents), then we have a short time window where we can report a number of used blocks to stat(2) that does not take into account the file region being overwritten. This short time window happens when completing the ordered extent(s). This happens because when we drop the extents in the write range we decrement the inode's number of bytes and later on when we insert the new extent(s) we increment the number of bytes in the inode, resulting in a short time window where a stat(2) syscall can get an incorrect number of used blocks. If we do writes that overwrite an entire file, then we have a short time window where we report 0 used blocks to stat(2). Example reproducer: $ cat reproducer-1.sh #!/bin/bash MNT=/mnt/sdi DEV=/dev/sdi stat_loop() { trap "wait; exit" SIGTERM local filepath=$1 local expected=$2 local got while :; do got=$(stat -c %b $filepath) if [ $got -ne $expected ]; then echo -n "ERROR: unexpected used blocks" echo " (got: $got expected: $expected)" fi done } mkfs.btrfs -f $DEV > /dev/null # mkfs.xfs -f $DEV > /dev/null # mkfs.ext4 -F $DEV > /dev/null # mkfs.f2fs -f $DEV > /dev/null # mkfs.reiserfs -f $DEV > /dev/null mount $DEV $MNT xfs_io -f -s -c "pwrite -b 64K 0 64K" $MNT/foobar >/dev/null expected=$(stat -c %b $MNT/foobar) # Create a process to keep calling stat(2) on the file and see if the # reported number of blocks used (disk space used) changes, it should # not because we are not increasing the file size nor punching holes. stat_loop $MNT/foobar $expected & loop_pid=$! for ((i = 0; i < 50000; i++)); do xfs_io -s -c "pwrite -b 64K 0 64K" $MNT/foobar >/dev/null done kill $loop_pid &> /dev/null wait umount $DEV $ ./reproducer-1.sh ERROR: unexpected used blocks (got: 0 expected: 128) ERROR: unexpected used blocks (got: 0 expected: 128) (...) Note that since this is a short time window where the race can happen, the reproducer may not be able to always trigger the bug in one run, or it may trigger it multiple times. -> Case 2 If we do a buffered write against a file region that does not have any allocated extents, like a hole or beyond EOF, then during ordered extent completion we have a short time window where a concurrent stat(2) syscall can report a number of used blocks that does not correspond to the value before or after the write operation, a value that is actually larger than the value after the write completes. This happens because once we start a buffered write into an unallocated file range we increment the inode's 'new_delalloc_bytes', to make sure any stat(2) call gets a correct used blocks value before delalloc is flushed and completes. However at ordered extent completion, after we inserted the new extent, we increment the inode's number of bytes used with the size of the new extent, and only later, when clearing the range in the inode's iotree, we decrement the inode's 'new_delalloc_bytes' counter with the size of the extent. So this results in a short time window where a concurrent stat(2) syscall can report a number of used blocks that accounts for the new extent twice. Example reproducer: $ cat reproducer-2.sh #!/bin/bash MNT=/mnt/sdi DEV=/dev/sdi stat_loop() { trap "wait; exit" SIGTERM local filepath=$1 local expected=$2 local got while :; do got=$(stat -c %b $filepath) if [ $got -ne $expected ]; then echo -n "ERROR: unexpected used blocks" echo " (got: $got expected: $expected)" fi done } mkfs.btrfs -f $DEV > /dev/null # mkfs.xfs -f $DEV > /dev/null # mkfs.ext4 -F $DEV > /dev/null # mkfs.f2fs -f $DEV > /dev/null # mkfs.reiserfs -f $DEV > /dev/null mount $DEV $MNT touch $MNT/foobar write_size=$((64 * 1024)) for ((i = 0; i < 16384; i++)); do offset=$(($i * $write_size)) xfs_io -c "pwrite -S 0xab $offset $write_size" $MNT/foobar >/dev/null blocks_used=$(stat -c %b $MNT/foobar) # Fsync the file to trigger writeback and keep calling stat(2) on it # to see if the number of blocks used changes. stat_loop $MNT/foobar $blocks_used & loop_pid=$! xfs_io -c "fsync" $MNT/foobar kill $loop_pid &> /dev/null wait $loop_pid done umount $DEV $ ./reproducer-2.sh ERROR: unexpected used blocks (got: 265472 expected: 265344) ERROR: unexpected used blocks (got: 284032 expected: 283904) (...) Note that since this is a short time window where the race can happen, the reproducer may not be able to always trigger the bug in one run, or it may trigger it multiple times. -> Case 3 Another case where such problems happen is during other operations that replace extents in a file range with other extents. Those operations are extent cloning, deduplication and fallocate's zero range operation. The cause of the problem is similar to the first case. When we drop the extents from a range, we decrement the inode's number of bytes, and later on, after inserting the new extents we increment it. Since this is not done atomically, a concurrent stat(2) call can see and return a number of used blocks that is smaller than it should be, does not match the number of used blocks before or after the clone/deduplication/zero operation. Like for the first case, when doing a clone, deduplication or zero range operation against an entire file, we end up having a time window where we can report 0 used blocks to a stat(2) call. Example reproducer: $ cat reproducer-3.sh #!/bin/bash MNT=/mnt/sdi DEV=/dev/sdi mkfs.btrfs -f $DEV > /dev/null # mkfs.xfs -f -m reflink=1 $DEV > /dev/null mount $DEV $MNT extent_size=$((64 * 1024)) num_extents=16384 file_size=$(($extent_size * $num_extents)) # File foo has many small extents. xfs_io -f -s -c "pwrite -S 0xab -b $extent_size 0 $file_size" $MNT/foo \ > /dev/null # File bar has much less extents and has exactly the same data as foo. xfs_io -f -c "pwrite -S 0xab 0 $file_size" $MNT/bar > /dev/null expected=$(stat -c %b $MNT/foo) # Now deduplicate bar into foo. While the deduplication is in progres, # the number of used blocks/file size reported by stat should not change xfs_io -c "dedupe $MNT/bar 0 0 $file_size" $MNT/foo > /dev/null & dedupe_pid=$! while [ -n "$(ps -p $dedupe_pid -o pid=)" ]; do used=$(stat -c %b $MNT/foo) if [ $used -ne $expected ]; then echo "Unexpected blocks used: $used (expected: $expected)" fi done umount $DEV $ ./reproducer-3.sh Unexpected blocks used: 2076800 (expected: 2097152) Unexpected blocks used: 2097024 (expected: 2097152) Unexpected blocks used: 2079872 (expected: 2097152) (...) Note that since this is a short time window where the race can happen, the reproducer may not be able to always trigger the bug in one run, or it may trigger it multiple times. So fix this by: 1) Making btrfs_drop_extents() not decrement the VFS inode's number of bytes, and instead return the number of bytes; 2) Making any code that drops extents and adds new extents update the inode's number of bytes atomically, while holding the btrfs inode's spinlock, which is also used by the stat(2) callback to get the inode's number of bytes; 3) For ranges in the inode's iotree that are marked as 'delalloc new', corresponding to previously unallocated ranges, increment the inode's number of bytes when clearing the 'delalloc new' bit from the range, in the same critical section that decrements the inode's 'new_delalloc_bytes' counter, delimited by the btrfs inode's spinlock. An alternative would be to have btrfs_getattr() wait for any IO (ordered extents in progress) and locking the whole range (0 to (u64)-1) while it it computes the number of blocks used. But that would mean blocking stat(2), which is a very used syscall and expected to be fast, waiting for writes, clone/dedupe, fallocate, page reads, fiemap, etc. CC: stable@vger.kernel.org # 5.4+ Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> |
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Filipe Manana
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5893dfb98f |
btrfs: refactor btrfs_drop_extents() to make it easier to extend
There are many arguments for __btrfs_drop_extents() and its wrapper
btrfs_drop_extents(), which makes it hard to add more arguments to it and
requires changing every caller. I have added a couple myself back in 2014
commit
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Josef Bacik
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b9729ce014 |
btrfs: locking: rip out path->leave_spinning
We no longer distinguish between blocking and spinning, so rip out all this code. Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> |
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Johannes Thumshirn
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6b613cc97f |
btrfs: reschedule when cloning lots of extents
We have several occurrences of a soft lockup from fstest's generic/175 testcase, which look more or less like this one: watchdog: BUG: soft lockup - CPU#0 stuck for 22s! [xfs_io:10030] Kernel panic - not syncing: softlockup: hung tasks CPU: 0 PID: 10030 Comm: xfs_io Tainted: G L 5.9.0-rc5+ #768 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.13.0-0-gf21b5a4-rebuilt.opensuse.org 04/01/2014 Call Trace: <IRQ> dump_stack+0x77/0xa0 panic+0xfa/0x2cb watchdog_timer_fn.cold+0x85/0xa5 ? lockup_detector_update_enable+0x50/0x50 __hrtimer_run_queues+0x99/0x4c0 ? recalibrate_cpu_khz+0x10/0x10 hrtimer_run_queues+0x9f/0xb0 update_process_times+0x28/0x80 tick_handle_periodic+0x1b/0x60 __sysvec_apic_timer_interrupt+0x76/0x210 asm_call_on_stack+0x12/0x20 </IRQ> sysvec_apic_timer_interrupt+0x7f/0x90 asm_sysvec_apic_timer_interrupt+0x12/0x20 RIP: 0010:btrfs_tree_unlock+0x91/0x1a0 [btrfs] RSP: 0018:ffffc90007123a58 EFLAGS: 00000282 RAX: ffff8881cea2fbe0 RBX: ffff8881cea2fbe0 RCX: 0000000000000000 RDX: ffff8881d23fd200 RSI: ffffffff82045220 RDI: ffff8881cea2fba0 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000032 R10: 0000160000000000 R11: 0000000000001000 R12: 0000000000001000 R13: ffff8882357fd5b0 R14: ffff88816fa76e70 R15: ffff8881cea2fad0 ? btrfs_tree_unlock+0x15b/0x1a0 [btrfs] btrfs_release_path+0x67/0x80 [btrfs] btrfs_insert_replace_extent+0x177/0x2c0 [btrfs] btrfs_replace_file_extents+0x472/0x7c0 [btrfs] btrfs_clone+0x9ba/0xbd0 [btrfs] btrfs_clone_files.isra.0+0xeb/0x140 [btrfs] ? file_update_time+0xcd/0x120 btrfs_remap_file_range+0x322/0x3b0 [btrfs] do_clone_file_range+0xb7/0x1e0 vfs_clone_file_range+0x30/0xa0 ioctl_file_clone+0x8a/0xc0 do_vfs_ioctl+0x5b2/0x6f0 __x64_sys_ioctl+0x37/0xa0 do_syscall_64+0x33/0x40 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7f87977fc247 RSP: 002b:00007ffd51a2f6d8 EFLAGS: 00000206 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f87977fc247 RDX: 00007ffd51a2f710 RSI: 000000004020940d RDI: 0000000000000003 RBP: 0000000000000004 R08: 00007ffd51a79080 R09: 0000000000000000 R10: 00005621f11352f2 R11: 0000000000000206 R12: 0000000000000000 R13: 0000000000000000 R14: 00005621f128b958 R15: 0000000080000000 Kernel Offset: disabled ---[ end Kernel panic - not syncing: softlockup: hung tasks ]--- All of these lockup reports have the call chain btrfs_clone_files() -> btrfs_clone() in common. btrfs_clone_files() calls btrfs_clone() with both source and destination extents locked and loops over the source extent to create the clones. Conditionally reschedule in the btrfs_clone() loop, to give some time back to other processes. CC: stable@vger.kernel.org # 4.4+ Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> |
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Filipe Manana
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306bfec02b |
btrfs: rename btrfs_punch_hole_range() to a more generic name
The function btrfs_punch_hole_range() is now used to replace all the file extents in a given file range with an extent described in the given struct btrfs_replace_extent_info argument. This extent can either be an existing extent that is being cloned or it can be a new extent (namely a prealloc extent). When that argument is NULL it only punches a hole (drops all the existing extents) in the file range. So rename the function to btrfs_replace_file_extents(). Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> |
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Filipe Manana
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bf385648fa |
btrfs: rename struct btrfs_clone_extent_info to a more generic name
Now that we can use btrfs_clone_extent_info to convey information for a new prealloc extent as well, and not just for existing extents that are being cloned, rename it to btrfs_replace_extent_info, which reflects the fact that this is now more generic and it is used to replace all existing extents in a file range with the extent described by the structure. Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> |
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Filipe Manana
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fb870f6cdd |
btrfs: remove item_size member of struct btrfs_clone_extent_info
The value of item_size of struct btrfs_clone_extent_info is always set to the size of a non-inline file extent item, and in fact the infrastructure that uses this structure (btrfs_punch_hole_range()) does not work with inline file extents at all (and it is not supposed to). So just remove that field from the structure and use directly sizeof(struct btrfs_file_extent_item) instead. Also assert that the file extent type is not inline at btrfs_insert_clone_extent(). Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> |
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Filipe Manana
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8fccebfa53 |
btrfs: fix metadata reservation for fallocate that leads to transaction aborts
When doing an fallocate(), specially a zero range operation, we assume that reserving 3 units of metadata space is enough, that at most we touch one leaf in subvolume/fs tree for removing existing file extent items and inserting a new file extent item. This assumption is generally true for most common use cases. However when we end up needing to remove file extent items from multiple leaves, we can end up failing with -ENOSPC and abort the current transaction, turning the filesystem to RO mode. When this happens a stack trace like the following is dumped in dmesg/syslog: [ 1500.620934] ------------[ cut here ]------------ [ 1500.620938] BTRFS: Transaction aborted (error -28) [ 1500.620973] WARNING: CPU: 2 PID: 30807 at fs/btrfs/inode.c:9724 __btrfs_prealloc_file_range+0x512/0x570 [btrfs] [ 1500.620974] Modules linked in: btrfs intel_rapl_msr intel_rapl_common kvm_intel (...) [ 1500.621010] CPU: 2 PID: 30807 Comm: xfs_io Tainted: G W 5.9.0-rc3-btrfs-next-67 #1 [ 1500.621012] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014 [ 1500.621023] RIP: 0010:__btrfs_prealloc_file_range+0x512/0x570 [btrfs] [ 1500.621026] Code: 8b 40 50 f0 48 (...) [ 1500.621028] RSP: 0018:ffffb05fc8803ca0 EFLAGS: 00010286 [ 1500.621030] RAX: 0000000000000000 RBX: ffff9608af276488 RCX: 0000000000000000 [ 1500.621032] RDX: 0000000000000001 RSI: 0000000000000027 RDI: 00000000ffffffff [ 1500.621033] RBP: ffffb05fc8803d90 R08: 0000000000000001 R09: 0000000000000001 [ 1500.621035] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000003200000 [ 1500.621037] R13: 00000000ffffffe4 R14: ffff9608af275fe8 R15: ffff9608af275f60 [ 1500.621039] FS: 00007fb5b2368ec0(0000) GS:ffff9608b6600000(0000) knlGS:0000000000000000 [ 1500.621041] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 1500.621043] CR2: 00007fb5b2366fb8 CR3: 0000000202d38005 CR4: 00000000003706e0 [ 1500.621046] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 1500.621047] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 1500.621049] Call Trace: [ 1500.621076] btrfs_prealloc_file_range+0x10/0x20 [btrfs] [ 1500.621087] btrfs_fallocate+0xccd/0x1280 [btrfs] [ 1500.621108] vfs_fallocate+0x14d/0x290 [ 1500.621112] ksys_fallocate+0x3a/0x70 [ 1500.621117] __x64_sys_fallocate+0x1a/0x20 [ 1500.621120] do_syscall_64+0x33/0x80 [ 1500.621123] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 1500.621126] RIP: 0033:0x7fb5b248c477 [ 1500.621128] Code: 89 7c 24 08 (...) [ 1500.621130] RSP: 002b:00007ffc7bee9060 EFLAGS: 00000293 ORIG_RAX: 000000000000011d [ 1500.621132] RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007fb5b248c477 [ 1500.621134] RDX: 0000000000000000 RSI: 0000000000000010 RDI: 0000000000000003 [ 1500.621136] RBP: 0000557718faafd0 R08: 0000000000000000 R09: 0000000000000000 [ 1500.621137] R10: 0000000003200000 R11: 0000000000000293 R12: 0000000000000010 [ 1500.621139] R13: 0000557718faafb0 R14: 0000557718faa480 R15: 0000000000000003 [ 1500.621151] irq event stamp: 1026217 [ 1500.621154] hardirqs last enabled at (1026223): [<ffffffffba965570>] console_unlock+0x500/0x5c0 [ 1500.621156] hardirqs last disabled at (1026228): [<ffffffffba9654c7>] console_unlock+0x457/0x5c0 [ 1500.621159] softirqs last enabled at (1022486): [<ffffffffbb6003dc>] __do_softirq+0x3dc/0x606 [ 1500.621161] softirqs last disabled at (1022477): [<ffffffffbb4010b2>] asm_call_on_stack+0x12/0x20 [ 1500.621162] ---[ end trace 2955b08408d8b9d4 ]--- [ 1500.621167] BTRFS: error (device sdj) in __btrfs_prealloc_file_range:9724: errno=-28 No space left When we use fallocate() internally, for reserving an extent for a space cache, inode cache or relocation, we can't hit this problem since either there aren't any file extent items to remove from the subvolume tree or there is at most one. When using plain fallocate() it's very unlikely, since that would require having many file extent items representing holes for the target range and crossing multiple leafs - we attempt to increase the range (merge) of such file extent items when punching holes, so at most we end up with 2 file extent items for holes at leaf boundaries. However when using the zero range operation of fallocate() for a large range (100+ MiB for example) that's fairly easy to trigger. The following example reproducer triggers the issue: $ cat reproducer.sh #!/bin/bash umount /dev/sdj &> /dev/null mkfs.btrfs -f -n 16384 -O ^no-holes /dev/sdj > /dev/null mount /dev/sdj /mnt/sdj # Create a 100M file with many file extent items. Punch a hole every 8K # just to speedup the file creation - we could do 4K sequential writes # followed by fsync (or O_SYNC) as well, but that takes a lot of time. file_size=$((100 * 1024 * 1024)) xfs_io -f -c "pwrite -S 0xab -b 10M 0 $file_size" /mnt/sdj/foobar for ((i = 0; i < $file_size; i += 8192)); do xfs_io -c "fpunch $i 4096" /mnt/sdj/foobar done # Force a transaction commit, so the zero range operation will be forced # to COW all metadata extents it need to touch. sync xfs_io -c "fzero 0 $file_size" /mnt/sdj/foobar umount /mnt/sdj $ ./reproducer.sh wrote 104857600/104857600 bytes at offset 0 100 MiB, 10 ops; 0.0669 sec (1.458 GiB/sec and 149.3117 ops/sec) fallocate: No space left on device $ dmesg <shows the same stack trace pasted before> To fix this use the existing infrastructure that hole punching and extent cloning use for replacing a file range with another extent. This deals with doing the removal of file extent items and inserting the new one using an incremental approach, reserving more space when needed and always ensuring we don't leave an implicit hole in the range in case we need to do multiple iterations and a crash happens between iterations. A test case for fstests will follow up soon. Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> |
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Nikolay Borisov
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998acfe8ff |
btrfs: make copy_inline_to_page take btrfs_inode
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> |
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Nikolay Borisov
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6fee248d2b |
btrfs: convert btrfs_inode_sectorsize to take btrfs_inode
It's counterintuitive to have a function named btrfs_inode_xxx which takes a generic inode. Also move the function to btrfs_inode.h so that it has access to the definition of struct btrfs_inode. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> |
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Filipe Manana
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3ebac17ce5 |
btrfs: reduce contention on log trees when logging checksums
The possibility of extents being shared (through clone and deduplication operations) requires special care when logging data checksums, to avoid having a log tree with different checksum items that cover ranges which overlap (which resulted in missing checksums after replaying a log tree). Such problems were fixed in the past by the following commits: commit |
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Nikolay Borisov
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e5b7231e20 |
btrfs: make btrfs_delalloc_reserve_space take btrfs_inode
All of its children take btrfs_inode so bubble up this requirement to btrfs_delalloc_reserve_space's interface and stop calling BTRFS_I internally. Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> |
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Nikolay Borisov
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86d52921a2 |
btrfs: make btrfs_delalloc_release_space take btrfs_inode
It needs btrfs_inode so take it as a parameter directly. Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> |
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Nikolay Borisov
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c2566f2289 |
btrfs: make btrfs_set_extent_delalloc take btrfs_inode
Preparation to make btrfs_dirty_pages take btrfs_inode as parameter. Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> |
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Filipe Manana
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4fdb688c70 |
btrfs: fix lost i_size update after cloning inline extent
When not using the NO_HOLES feature we were not marking the destination's
file range as written after cloning an inline extent into it. This can
lead to a data loss if the current destination file size is smaller than
the source file's size.
Example:
$ mkfs.btrfs -f -O ^no-holes /dev/sdc
$ mount /mnt/sdc /mnt
$ echo "hello world" > /mnt/foo
$ cp --reflink=always /mnt/foo /mnt/bar
$ rm -f /mnt/foo
$ umount /mnt
$ mount /mnt/sdc /mnt
$ cat /mnt/bar
$
$ stat -c %s /mnt/bar
0
# -> the file is empty, since we deleted foo, the data lost is forever
Fix that by calling btrfs_inode_set_file_extent_range() after cloning an
inline extent.
A test case for fstests will follow soon.
Link: https://lore.kernel.org/linux-btrfs/20200404193846.GA432065@latitude/
Reported-by: Johannes Hirte <johannes.hirte@datenkhaos.de>
Fixes:
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Filipe Manana
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05a5a7621c |
Btrfs: implement full reflink support for inline extents
There are a few cases where we don't allow cloning an inline extent into the destination inode, returning -EOPNOTSUPP to user space. This was done to prevent several types of file corruption and because it's not very straightforward to deal with these cases, as they can't rely on simply copying the inline extent between leaves. Such cases require copying the inline extent's data into the respective page of the destination inode. Not supporting these cases makes it harder and more cumbersome to write applications/libraries that work on any filesystem with reflink support, since all these cases for which btrfs fails with -EOPNOTSUPP work just fine on xfs for example. These unsupported cases are also not documented anywhere and explaining which exact cases fail require a bit of too technical understanding of btrfs's internal (inline extents and when and where can they exist in a file), so it's not really user friendly. Also some test cases from fstests that use fsx, such as generic/522 for example, can sporadically fail because they trigger one of these cases, and fsx expects all operations to succeed. This change adds supports for cloning all these cases by copying the inline extent's data into the respective page of the destination inode. With this change test case btrfs/112 from fstests fails because it expects some clone operations to fail, so it will be updated. Also a new test case that exercises all these previously unsupported cases will be added to fstests. Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> |
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Filipe Manana
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a61e1e0df9 |
Btrfs: simplify inline extent handling when doing reflinks
We can not reflink parts of an inline extent, we must always reflink the
whole inline extent. We know that inline extents always start at file
offset 0 and that can never represent an amount of data larger then the
filesystem's sector size (both compressed and uncompressed). We also have
had the constraints that reflink operations must have a start offset that
is aligned to the sector size and an end offset that is also aligned or
it ends the inode's i_size, so there's no way for user space to be able
to do a reflink operation that will refer to only a part of an inline
extent.
Initially there was a bug in the inlining code that could allow compressed
inline extents that encoded more than 1 page, but that was fixed in 2008
by commit
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Filipe Manana
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6a17738100 |
Btrfs: move all reflink implementation code into its own file
The reflink code is quite large and has been living in ioctl.c since ever. It has grown over the years after many bug fixes and improvements, and since I'm planning on making some further improvements on it, it's time to get it better organized by moving into its own file, reflink.c (similar to what xfs does for example). This change only moves the code out of ioctl.c into the new file, it doesn't do any other change. Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> |