- 01 Aug, 2016 7 commits
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Robbie Ko authored
During an incremental send, if we have delayed rename operations for inodes that were children of directories which were removed in the send snapshot, we can end up accessing incorrect items in a leaf or accessing beyond the last item of the leaf due to issuing utimes operations for the removed inodes. Consider the following example: Parent snapshot: . (ino 256) |--- a/ (ino 257) | |--- c/ (ino 262) | |--- b/ (ino 258) | |--- d/ (ino 263) | |--- del/ (ino 261) |--- x/ (ino 259) |--- y/ (ino 260) Send snapshot: . (ino 256) |--- a/ (ino 257) | |--- b/ (ino 258) | |--- c/ (ino 262) | |--- y/ (ino 260) | |--- d/ (ino 263) |--- x/ (ino 259) 1) When processing inodes 259 and 260, we end up delaying their rename operations because their parents, inodes 263 and 262 respectively, were not yet processed and therefore not yet renamed; 2) When processing inode 262, its rename operation is issued and right after the rename operation for inode 260 is issued. However right after issuing the rename operation for inode 260, at send.c:apply_dir_move(), we issue utimes operations for all current and past parents of inode 260. This means we try to send a utimes operation for its old parent, inode 261 (deleted in the send snapshot), which does not cause any immediate and deterministic failure, because when the target inode is not found in the send snapshot, the send.c:send_utimes() function ignores it and uses the leaf region pointed to by path->slots[0], which can be any unrelated item (belonging to other inode) or it can be a region outside the leaf boundaries, if the leaf is full and path->slots[0] matches the number of items in the leaf. So we end up either successfully sending a utimes operation, which is fine and irrelevant because the old parent (inode 261) will end up being deleted later, or we end up doing an invalid memory access tha crashes the kernel. So fix this by making apply_dir_move() issue utimes operations only for parents that still exist in the send snapshot. In a separate patch we will make send_utimes() return an error (-ENOENT) if the given inode does not exists in the send snapshot. Signed-off-by:Robbie Ko <robbieko@synology.com> Signed-off-by:
Filipe Manana <fdmanana@suse.com> [Rewrote change log to be more detailed and better organized] Signed-off-by:
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Robbie Ko authored
Under certain situations, when doing an incremental send, we can end up not freeing orphan_dir_info structures as soon as they are no longer needed. Instead we end up freeing them only after finishing the send stream, which causes a warning to be emitted: [282735.229200] ------------[ cut here ]------------ [282735.229968] WARNING: CPU: 9 PID: 10588 at fs/btrfs/send.c:6298 btrfs_ioctl_send+0xe2f/0xe51 [btrfs] [282735.231282] Modules linked in: btrfs crc32c_generic xor raid6_pq acpi_cpufreq tpm_tis ppdev tpm parport_pc psmouse parport sg pcspkr i2c_piix4 i2c_core evdev processor serio_raw button loop autofs4 ext4 crc16 jbd2 mbcache sr_mod cdrom sd_mod ata_generic virtio_scsi ata_piix libata virtio_pci virtio_ring virtio e1000 scsi_mod floppy [last unloaded: btrfs] [282735.237130] CPU: 9 PID: 10588 Comm: btrfs Tainted: G W 4.6.0-rc7-btrfs-next-31+ #1 [282735.239309] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS by qemu-project.org 04/01/2014 [282735.240160] 0000000000000000 ffff880224273ca8 ffffffff8126b42c 0000000000000000 [282735.240160] 0000000000000000 ffff880224273ce8 ffffffff81052b14 0000189a24273ac8 [282735.240160] ffff8802210c9800 0000000000000000 0000000000000001 0000000000000000 [282735.240160] Call Trace: [282735.240160] [<ffffffff8126b42c>] dump_stack+0x67/0x90 [282735.240160] [<ffffffff81052b14>] __warn+0xc2/0xdd [282735.240160] [<ffffffff81052beb>] warn_slowpath_null+0x1d/0x1f [282735.240160] [<ffffffffa03c99d5>] btrfs_ioctl_send+0xe2f/0xe51 [btrfs] [282735.240160] [<ffffffffa0398358>] btrfs_ioctl+0x14f/0x1f81 [btrfs] [282735.240160] [<ffffffff8108e456>] ? arch_local_irq_save+0x9/0xc [282735.240160] [<ffffffff8118da05>] vfs_ioctl+0x18/0x34 [282735.240160] [<ffffffff8118e00c>] do_vfs_ioctl+0x550/0x5be [282735.240160] [<ffffffff81196f0c>] ? __fget+0x6b/0x77 [282735.240160] [<ffffffff81196fa1>] ? __fget_light+0x62/0x71 [282735.240160] [<ffffffff8118e0d1>] SyS_ioctl+0x57/0x79 [282735.240160] [<ffffffff8149e025>] entry_SYSCALL_64_fastpath+0x18/0xa8 [282735.240160] [<ffffffff81100c6b>] ? time_hardirqs_off+0x9/0x14 [282735.240160] [<ffffffff8108e87d>] ? trace_hardirqs_off_caller+0x1f/0xaa [282735.256343] ---[ end trace a4539270c8056f93 ]--- Consider the following example: Parent snapshot: . (ino 256) |--- a/ (ino 257) | |--- c/ (ino 260) | |--- del/ (ino 259) |--- tmp/ (ino 258) |--- x/ (ino 261) |--- y/ (ino 262) Send snapshot: . (ino 256) |--- a/ (ino 257) | |--- x/ (ino 261) | |--- y/ (ino 262) | |--- c/ (ino 260) |--- tmp/ (ino 258) 1) When processing inode 258, we end up delaying its rename operation because it has an ancestor (in the send snapshot) that has a higher inode number (inode 260) which was also renamed in the send snapshot, therefore we delay the rename of inode 258 so that it happens after inode 260 is renamed; 2) When processing inode 259, we end up delaying its deletion (rmdir operation) because it has a child inode (258) that has its rename operation delayed. At this point we allocate an orphan_dir_info structure and tag inode 258 so that we later attempt to see if we can delete (rmdir) inode 259 once inode 258 is renamed; 3) When we process inode 260, after renaming it we finally do the rename operation for inode 258. Once we issue the rename operation for inode 258 we notice that this inode was tagged so that we attempt to see if at this point we can delete (rmdir) inode 259. But at this point we can not still delete inode 259 because it has 2 children, inodes 261 and 262, that were not yet processed and therefore not yet moved (renamed) away from inode 259. We end up not freeing the orphan_dir_info structure allocated in step 2; 4) We process inodes 261 and 262, and once we move/rename inode 262 we issue the rmdir operation for inode 260; 5) We finish the send stream and notice that red black tree that contains orphan_dir_info structures is not empty, so we emit a warning and then free any orphan_dir_structures left. So fix this by freeing an orphan_dir_info structure once we try to apply a pending rename operation if we can not delete yet the tagged directory. A test case for fstests follows soon. Signed-off-by: -
Robbie Ko authored
Under certain situations, an incremental send operation can contain a rmdir operation that will make the receiving end fail when attempting to execute it, because the target directory is not yet empty. Consider the following example: Parent snapshot: . (ino 256) |--- a/ (ino 257) | |--- c/ (ino 260) | |--- del/ (ino 259) |--- tmp/ (ino 258) |--- x/ (ino 261) Send snapshot: . (ino 256) |--- a/ (ino 257) | |--- x/ (ino 261) | |--- c/ (ino 260) |--- tmp/ (ino 258) 1) When processing inode 258, we delay its rename operation because inode 260 is its new parent in the send snapshot and it was not yet renamed (since 260 > 258, that is, beyond the current progress); 2) When processing inode 259, we realize we can not yet send an rmdir operation (against inode 259) because inode 258 was still not yet renamed/moved away from inode 259. Therefore we update data structures so that after inode 258 is renamed, we try again to see if we can finally send an rmdir operation for inode 259; 3) When we process inode 260, we send a rename operation for it followed by a rename operation for inode 258. Once we send the rename operation for inode 258 we then check if we can finally issue an rmdir for its previous parent, inode 259, by calling the can_rmdir() function with a value of sctx->cur_ino + 1 (260 + 1 = 261) for its "progress" argument. This makes can_rmdir() return true (value 1) because even though there's still a child inode of inode 259 that was not yet renamed/moved, which is inode 261, the given value of progress (261) is not lower then 261 (that is, not lower than the inode number of some child of inode 259). So we end up sending a rmdir operation for inode 259 before its child inode 261 is processed and renamed. So fix this by passing the correct progress value to the call to can_rmdir() from within apply_dir_move() (where we issue delayed rename operations), which should match stcx->cur_ino (the number of the inode currently being processed) and not sctx->cur_ino + 1. A test case for fstests follows soon. Signed-off-by: -
Filipe Manana authored
Example scenario: Parent snapshot: . (ino 277) |---- tmp/ (ino 278) |---- pre/ (ino 280) | |---- wait_dir/ (ino 281) | |---- desc/ (ino 282) |---- ance/ (ino 283) | |---- below_ance/ (ino 279) | |---- other_dir/ (ino 284) Send snapshot: . (ino 277) |---- tmp/ (ino 278) |---- other_dir/ (ino 284) |---- below_ance/ (ino 279) | |---- pre/ (ino 280) | |---- wait_dir/ (ino 281) |---- desc/ (ino 282) |---- ance/ (ino 283) While computing the send stream the following steps happen: 1) While processing inode 279 we end up delaying its rename operation because its new parent in the send snapshot, inode 284, was not yet processed and therefore not yet renamed; 2) Later when processing inode 280 we end up renaming it immediately to "ance/below_once/pre" and not delay its rename operation because its new parent (inode 279 in the send snapshot) has its rename operation delayed and inode 280 is not an encestor of inode 279 (its parent in the send snapshot) in the parent snapshot; 3) When processing inode 281 we end up delaying its rename operation because its new parent in the send snapshot, inode 284, was not yet processed and therefore not yet renamed; 4) When processing inode 282 we do not delay its rename operation because its parent in the send snapshot, inode 281, already has its own rename operation delayed and our current inode (282) is not an ancestor of inode 281 in the parent snapshot. Therefore inode 282 is renamed to "ance/below_ance/pre/wait_dir"; 5) When processing inode 283 we realize that we can rename it because one of its ancestors in the send snapshot, inode 281, has its rename operation delayed and inode 283 is not an ancestor of inode 281 in the parent snapshot. So a rename operation to rename inode 283 to "ance/below_ance/pre/wait_dir/desc/ance" is issued. This path is invalid due to a missing path building loop that was undetected by the incremental send implementation, as inode 283 ends up getting included twice in the path (once with its path in the parent snapshot). Therefore its rename operation must wait before the ancestor inode 284 is renamed. Fix this by not terminating the rename dependency checks when we find an ancestor, in the send snapshot, that has its rename operation delayed. So that we continue doing the same checks if the current inode is not an ancestor, in the parent snapshot, of an ancestor in the send snapshot we are processing in the loop. The problem and reproducer were reported by Robbie Ko, as part of a patch titled "Btrfs: incremental send, avoid ancestor rename to descendant". However the fix was unnecessarily complicated and can be addressed with much less code and effort. Reported-by: -
Filipe Manana authored
The function path_loop() can return a negative integer, signaling an error, 0 if there's no path loop and 1 if there's a path loop. We were treating any non zero values as meaning that a path loop exists. Fix this by explicitly checking for errors and gracefully return them to user space. Signed-off-by: -
Robbie Ko authored
When doing an incremental send we can end up not moving directories that have the same name. This happens when the same parent directory has different child directories with the same name in the parent and send snapshots. For example, consider the following scenario: Parent snapshot: . (ino 256) |---- d/ (ino 257) | |--- p1/ (ino 258) | |---- p1/ (ino 259) Send snapshot: . (ino 256) |--- d/ (ino 257) |--- p1/ (ino 259) |--- p1/ (ino 258) The directory named "d" (inode 257) has in both snapshots an entry with the name "p1" but it refers to different inodes in both snapshots (inode 258 in the parent snapshot and inode 259 in the send snapshot). When attempting to move inode 258, the operation is delayed because its new parent, inode 259, was not yet moved/renamed (as the stream is currently processing inode 258). Then when processing inode 259, we also end up delaying its move/rename operation so that it happens after inode 258 is moved/renamed. This decision to delay the move/rename rename operation of inode 259 is due to the fact that the new parent inode (257) still has inode 258 as its child, which has the same name has inode 259. So we end up with inode 258 move/rename operation waiting for inode's 259 move/rename operation, which in turn it waiting for inode's 258 move/rename. This results in ending the send stream without issuing move/rename operations for inodes 258 and 259 and generating the following warnings in syslog/dmesg: [148402.979747] ------------[ cut here ]------------ [148402.980588] WARNING: CPU: 14 PID: 4117 at fs/btrfs/send.c:6177 btrfs_ioctl_send+0xe03/0xe51 [btrfs] [148402.981928] Modules linked in: btrfs crc32c_generic xor raid6_pq acpi_cpufreq tpm_tis ppdev tpm parport_pc psmouse parport sg pcspkr i2c_piix4 i2c_core evdev processor serio_raw button loop autofs4 ext4 crc16 jbd2 mbcache sr_mod cdrom sd_mod ata_generic virtio_scsi ata_piix libata virtio_pci virtio_ring virtio e1000 scsi_mod floppy [last unloaded: btrfs] [148402.986999] CPU: 14 PID: 4117 Comm: btrfs Tainted: G W 4.6.0-rc7-btrfs-next-31+ #1 [148402.988136] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS by qemu-project.org 04/01/2014 [148402.988136] 0000000000000000 ffff88022139fca8 ffffffff8126b42c 0000000000000000 [148402.988136] 0000000000000000 ffff88022139fce8 ffffffff81052b14 000018212139fac8 [148402.988136] ffff88022b0db400 0000000000000000 0000000000000001 0000000000000000 [148402.988136] Call Trace: [148402.988136] [<ffffffff8126b42c>] dump_stack+0x67/0x90 [148402.988136] [<ffffffff81052b14>] __warn+0xc2/0xdd [148402.988136] [<ffffffff81052beb>] warn_slowpath_null+0x1d/0x1f [148402.988136] [<ffffffffa04bc831>] btrfs_ioctl_send+0xe03/0xe51 [btrfs] [148402.988136] [<ffffffffa048b358>] btrfs_ioctl+0x14f/0x1f81 [btrfs] [148402.988136] [<ffffffff8108e456>] ? arch_local_irq_save+0x9/0xc [148402.988136] [<ffffffff8108eb51>] ? __lock_is_held+0x3c/0x57 [148402.988136] [<ffffffff8118da05>] vfs_ioctl+0x18/0x34 [148402.988136] [<ffffffff8118e00c>] do_vfs_ioctl+0x550/0x5be [148402.988136] [<ffffffff81196f0c>] ? __fget+0x6b/0x77 [148402.988136] [<ffffffff81196fa1>] ? __fget_light+0x62/0x71 [148402.988136] [<ffffffff8118e0d1>] SyS_ioctl+0x57/0x79 [148402.988136] [<ffffffff8149e025>] entry_SYSCALL_64_fastpath+0x18/0xa8 [148402.988136] [<ffffffff8108e89d>] ? trace_hardirqs_off_caller+0x3f/0xaa [148403.011373] ---[ end trace a4539270c8056f8b ]--- [148403.012296] ------------[ cut here ]------------ [148403.013071] WARNING: CPU: 14 PID: 4117 at fs/btrfs/send.c:6194 btrfs_ioctl_send+0xe19/0xe51 [btrfs] [148403.014447] Modules linked in: btrfs crc32c_generic xor raid6_pq acpi_cpufreq tpm_tis ppdev tpm parport_pc psmouse parport sg pcspkr i2c_piix4 i2c_core evdev processor serio_raw button loop autofs4 ext4 crc16 jbd2 mbcache sr_mod cdrom sd_mod ata_generic virtio_scsi ata_piix libata virtio_pci virtio_ring virtio e1000 scsi_mod floppy [last unloaded: btrfs] [148403.019708] CPU: 14 PID: 4117 Comm: btrfs Tainted: G W 4.6.0-rc7-btrfs-next-31+ #1 [148403.020104] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS by qemu-project.org 04/01/2014 [148403.020104] 0000000000000000 ffff88022139fca8 ffffffff8126b42c 0000000000000000 [148403.020104] 0000000000000000 ffff88022139fce8 ffffffff81052b14 000018322139fac8 [148403.020104] ffff88022b0db400 0000000000000000 0000000000000001 0000000000000000 [148403.020104] Call Trace: [148403.020104] [<ffffffff8126b42c>] dump_stack+0x67/0x90 [148403.020104] [<ffffffff81052b14>] __warn+0xc2/0xdd [148403.020104] [<ffffffff81052beb>] warn_slowpath_null+0x1d/0x1f [148403.020104] [<ffffffffa04bc847>] btrfs_ioctl_send+0xe19/0xe51 [btrfs] [148403.020104] [<ffffffffa048b358>] btrfs_ioctl+0x14f/0x1f81 [btrfs] [148403.020104] [<ffffffff8108e456>] ? arch_local_irq_save+0x9/0xc [148403.020104] [<ffffffff8108eb51>] ? __lock_is_held+0x3c/0x57 [148403.020104] [<ffffffff8118da05>] vfs_ioctl+0x18/0x34 [148403.020104] [<ffffffff8118e00c>] do_vfs_ioctl+0x550/0x5be [148403.020104] [<ffffffff81196f0c>] ? __fget+0x6b/0x77 [148403.020104] [<ffffffff81196fa1>] ? __fget_light+0x62/0x71 [148403.020104] [<ffffffff8118e0d1>] SyS_ioctl+0x57/0x79 [148403.020104] [<ffffffff8149e025>] entry_SYSCALL_64_fastpath+0x18/0xa8 [148403.020104] [<ffffffff8108e89d>] ? trace_hardirqs_off_caller+0x3f/0xaa [148403.038981] ---[ end trace a4539270c8056f8c ]--- There's another issue caused by similar (but more complex) changes in the directory hierarchy that makes move/rename operations fail, described with the following example: Parent snapshot: . |---- a/ (ino 262) | |---- c/ (ino 268) | |---- d/ (ino 263) |---- ance/ (ino 267) |---- e/ (ino 264) |---- f/ (ino 265) |---- ance/ (ino 266) Send snapshot: . |---- a/ (ino 262) |---- c/ (ino 268) | |---- ance/ (ino 267) | |---- d/ (ino 263) | |---- ance/ (ino 266) | |---- f/ (ino 265) |---- e/ (ino 264) When the inode 265 is processed, the path for inode 267 is computed, which at that time corresponds to "d/ance", and it's stored in the names cache. Later on when processing inode 266, we end up orphanizing (renaming to a name matching the pattern o<ino>-<gen>-<seq>) inode 267 because it has the same name as inode 266 and it's currently a child of the new parent directory (inode 263) for inode 266. After the orphanization and while we are still processing inode 266, a rename operation for inode 266 is generated. However the source path for that rename operation is incorrect because it ends up using the old, pre-orphanization, name of inode 267. The no longer valid name for inode 267 was previously cached when processing inode 265 and it remains usable and considered valid until the inode currently being processed has a number greater than 267. This resulted in the receiving side failing with the following error: ERROR: rename d/ance/ance -> d/ance failed: No such file or directory So fix these issues by detecting such circular dependencies for rename operations and by clearing the cached name of an inode once the inode is orphanized. A test case for fstests will follow soon. Signed-off-by: -
Filipe Manana authored
When we start an fsync we start ordered extents for all delalloc ranges. However before attempting to log the inode, we only wait for those ordered extents if we are not doing a full sync (bit BTRFS_INODE_NEEDS_FULL_SYNC is set in the inode's flags). This means that if an ordered extent completes with an IO error before we check if we can skip logging the inode, we will not catch and report the IO error to user space. This is because on an IO error, when the ordered extent completes we do not update the inode, so if the inode was not previously updated by the current transaction we end up not logging it through calls to fsync and therefore not check its mapping flags for the presence of IO errors. Fix this by checking for errors in the flags of the inode's mapping when we notice we can skip logging the inode. This caused sporadic failures in the test generic/331 (which explicitly tests for IO errors during an fsync call). Signed-off-by:
Liu Bo <bo.li.liu@oracle.com>
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- 21 Jul, 2016 1 commit
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Chris Mason authored
Commit 56244ef1 was almost but not quite enough to fix the reservation math after btrfs_copy_from_user returned partial copies. Some users are still seeing warnings in btrfs_destroy_inode, and with a long enough test run I'm able to trigger them as well. This patch fixes the accounting math again, bringing it much closer to the way it was before the sectorsize conversion Chandan did. The problem is accounting for the offset into the page/sector when we do a partial copy. This one just uses the dirty_sectors variable which should already be updated properly. Signed-off-by:
Chris Mason <clm@fb.com> cc: stable@vger.kernel.org # v4.6+
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- 20 Jul, 2016 2 commits
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Josef Bacik authored
The new enospc code makes it possible to deadlock if we don't use FLUSH_LIMIT during reservations inside a transaction. This enforces the correct flush type to avoid both deadlocks and assertions Signed-off-by:
Josef Bacik <jbacik@fb.com>
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Chris Mason authored
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- 07 Jul, 2016 18 commits
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Josef Bacik authored
We used to allow you to set FLUSH_ALL and then just wouldn't do things like commit transactions or wait on ordered extents if we noticed you were in a transaction. However now that all the flushing for FLUSH_ALL is asynchronous we've lost the ability to tell, and we could end up deadlocking. So instead use FLUSH_LIMIT in reserve_metadata_bytes in relocation and then return -EAGAIN if we error out to preserve the previous behavior. I've also added an ASSERT() to catch anybody else who tries to do this. Thanks, Signed-off-by:
David Sterba <dsterba@suse.com>
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Josef Bacik authored
Since we set the reloc control before we've reserved our space for relocation we could race with a root being dirtied and not actually have space to do our init reloc root. So once we've allocated it and set it up go ahead and make our reservation before setting the relocate control, that way anybody who tries to do the reloc root init has space to use. Thanks, Signed-off-by:
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Josef Bacik authored
This is the case all the time anyway except for relocation which could be doing a reloc root for a non ref counted root, in which case we'd end up with some random block rsv rather than the one we have our reservation in. If there isn't enough space in the block rsv we are trying to steal from we'll BUG() because we expect there to be space for the orphan to make its reservation. Thanks, Signed-off-by:
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Josef Bacik authored
Traditionally we've calculated the global block rsv by guessing how much of the metadata used amount was the extent tree, and then taking the data size and figuring out how large the csum tree would have to be to hold that much data. This is imprecise and falls down on MIXED file systems as we can't trust the data used amount. This resulted in failures for xfstests generic/333 because it creates lots of clones, which explodes out the extent tree. Our global reserve calculations were woefully inaccurate in this case which meant we got into a situation where we did not have enough reserved to do our work. We know we only use the global block rsv for the extent, csum, and root trees, so just get the bytes used for these trees and use that as the basis of our global reserve. Since these are not reference counted trees the bytes_used value will be accurate. This fixed the transaction aborts seen with generic/333. Thanks, Signed-off-by:
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Josef Bacik authored
Instead of doing fs_info->fs_root in need_async_flush, which may not be set during recovery when mounting, just pass the root itself in, which makes more sense as thats what btrfs_calc_reclaim_metadata_size takes. Signed-off-by:
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Josef Bacik authored
We do this check when we start the async reclaimer thread, might as well check before we kick it off to save us some cycles. Thanks, Signed-off-by:
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Josef Bacik authored
We were doing trace_btrfs_release_reserved_extent() in pin_down_extent which isn't quite right because we will go through and free that extent later when we unpin, so it messes up apps that are accounting for the reservation space. We were also unconditionally doing it in __btrfs_free_reserved_extent(), when we only actually free the reservation instead of pinning the extent. Thanks, Signed-off-by:
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Josef Bacik authored
When tracing enospc problems on a box with multiple file systems mounted I need to be able to differentiate between the two file systems. Most of the important trace points I'm looking at already have an fsid, but the reserved extent trace points do not, so add that to make it possible to figure out which trace point belongs to which file system. Thanks, Signed-off-by:
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Josef Bacik authored
We want to track when we're triggering flushing from our reservation code and what flushing is being done when we start flushing. Thanks, Signed-off-by:
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Josef Bacik authored
We can sometimes drop the reservation we had for our inode, so we need to remove that amount from to_reserve so that our tracepoint reports a valid amount of space. Signed-off-by:
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Josef Bacik authored
Pinned extents are an important metric to keep track of for enospc. Signed-off-by:
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Josef Bacik authored
Our enospc flushing sucks. It is born from a time where we were early enospc'ing constantly because multiple threads would race in for the same reservation and randomly starve other ones out. So I came up with this solution to block any other reservations from happening while one guy tried to flush stuff to satisfy his reservation. This gives us pretty good correctness, but completely crap latency. The solution I've come up with is ticketed reservations. Basically we try to make our reservation, and if we can't we put a ticket on a list in order and kick off an async flusher thread. This async flusher thread does the same old flushing we always did, just asynchronously. As space is freed and added back to the space_info it checks and sees if we have any tickets that need satisfying, and adds space to the tickets and wakes up anything we've satisfied. Once the flusher thread stops making progress it wakes up all the current tickets and tells them to take a hike. There is a priority list for things that can't flush, since the async flusher could do anything we need to avoid deadlocks. These guys get priority for having their reservation made, and will still do manual flushing themselves in case the async flusher isn't running. This patch gives us significantly better latencies. Thanks, Signed-off-by:
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Josef Bacik authored
I'm writing a tool to visualize the enospc system inside btrfs, I need this tracepoint in order to keep track of the block groups in the system. Thanks, Signed-off-by:
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Josef Bacik authored
These were hidden behind enospc_debug, which isn't helpful as they indicate actual bugs, unlike the rest of the enospc_debug stuff which is really debug information. Thanks, Signed-off-by:
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Josef Bacik authored
We reserve space for the inode update when we first reserve space for writing to a file. However there are lots of ways that we can use this reservation and not have it for subsequent ordered extents. Previously we'd fall through and try to reserve metadata bytes for this, then we'd just steal the full reservation from the delalloc_block_rsv, and if that didn't have enough space we'd steal the full reservation from the global reserve. The problem with this is we can easily just return ENOSPC and fallback to updating the inode item directly. In the worst case (assuming 4k nodesize) we'd steal 64kib from the global reserve if we fall all the way through, however if we just fallback and update the inode directly we'd only steal 4k * BTRFS_PATH_MAX in the worst case which is 32kib. We would have also just added the extent item for the inode so we likely will have already cow'ed down most of the way to the leaf containing the inode item, so we are more often than not only need one or two nodesize's worth of reservations. Given the reservation for the extent itself is also a worst case we will likely already have space to cover the inode update. This change will make us behave better in the theoretical worst case, and much better in the case that we don't have our reservation and cannot reserve more metadata. Thanks, Signed-off-by:
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Josef Bacik authored
There are a few races in the metadata reservation stuff. First we add the bytes to the block_rsv well after we've set the bit on the inode saying that we have space for it and after we've reserved the bytes. So use the normal btrfs_block_rsv_add helper for this case. Secondly we can flush delalloc extents when we try to reserve space for our write, which means that we could have used up the space for the inode and we wouldn't know because we only check before the reservation. So instead make sure we are always reserving space for the inode update, and then if we don't need it release those bytes afterward. Thanks, Signed-off-by:
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Josef Bacik authored
So btrfs_block_rsv_migrate just unconditionally calls block_rsv_migrate_bytes. Not only this but it unconditionally changes the size of the block_rsv. This isn't a bug strictly speaking, but it makes truncate block rsv's look funny because every time we migrate bytes over its size grows, even though we only want it to be a specific size. So collapse this into one function that takes an update_size argument and make truncate and evict not update the size for consistency sake. Thanks, Signed-off-by:
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Josef Bacik authored
For some reason we're adding bytes_readonly to the space info after we update the space info with the block group info. This creates a tiny race where we could over-reserve space because we haven't yet taken out the bytes_readonly bit. Since we already know this information at the time we call update_space_info, just pass it along so it can be updated all at once. Thanks, Signed-off-by:
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- 04 Jul, 2016 1 commit
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Linus Torvalds authored
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- 03 Jul, 2016 5 commits
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git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuseLinus Torvalds authored
Pull fuse fix from Miklos Szeredi: "This makes sure userspace filesystems are not broken by the parallel lookups and readdir feature" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse: fuse: serialize dirops by default
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git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfsLinus Torvalds authored
Pull overlayfs fixes from Miklos Szeredi: "This contains fixes for a dentry leak, a regression in 4.6 noticed by Docker users and missing write access checking in truncate" * 'overlayfs-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs: ovl: warn instead of error if d_type is not supported ovl: get_write_access() in truncate ovl: fix dentry leak for default_permissions
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Vivek Goyal authored
overlay needs underlying fs to support d_type. Recently I put in a patch in to detect this condition and started failing mount if underlying fs did not support d_type. But this breaks existing configurations over kernel upgrade. Those who are running docker (partially broken configuration) with xfs not supporting d_type, are surprised that after kernel upgrade docker does not run anymore. https://github.com/docker/docker/issues/22937#issuecomment-229881315 So instead of erroring out, detect broken configuration and warn about it. This should allow existing docker setups to continue working after kernel upgrade. Signed-off-by:
Vivek Goyal <vgoyal@redhat.com> Signed-off-by:
Miklos Szeredi <mszeredi@redhat.com> Fixes: 45aebeaf ("ovl: Ensure upper filesystem supports d_type") Cc: <stable@vger.kernel.org> 4.6
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git://git.linux-mips.org/pub/scm/ralf/upstream-linusLinus Torvalds authored
Pull MIPS fix from Ralf Baechle: "Only a single fix for 4.7 pending at this point. It fixes an issue that may lead to corruption of the cache mode bits in the page table" * 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: MIPS: Fix possible corruption of cache mode by mprotect.
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git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linuxLinus Torvalds authored
Pull powerpc fixes from Michael Ellerman: - tm: Always reclaim in start_thread() for exec() class syscalls from Cyril Bur - tm: Avoid SLB faults in treclaim/trecheckpoint when RI=0 from Michael Neuling - eeh: Fix wrong argument passed to eeh_rmv_device() from Gavin Shan - Initialise pci_io_base as early as possible from Darren Stevens * tag 'powerpc-4.7-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: powerpc: Initialise pci_io_base as early as possible powerpc/tm: Avoid SLB faults in treclaim/trecheckpoint when RI=0 powerpc/eeh: Fix wrong argument passed to eeh_rmv_device() powerpc/tm: Always reclaim in start_thread() for exec() class syscalls
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- 02 Jul, 2016 6 commits
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git://people.freedesktop.org/~airlied/linuxLinus Torvalds authored
Pull drm fixes frlm Dave Airlie: "Just some AMD and Intel fixes, the AMD ones are further production Polaris fixes, and the Intel ones fix some early timeouts, some PCI ID changes and a couple of other fixes. Still a bit Internet challenged here, hopefully end of next week will solve it" * tag 'drm-fixes-for-v4.7-rc6' of git://people.freedesktop.org/~airlied/linux: drm/i915: Fix missing unlock on error in i915_ppgtt_info() drm/amd/powerplay: workaround for UVD clock issue drm/amdgpu: add ACLK_CNTL setting for polaris10 drm/amd/powerplay: fix issue uvd dpm can't enabled on Polaris11. drm/amd/powerplay: Workaround for Memory EDC Error on Polaris10. drm/i915: Removing PCI IDs that are no longer listed as Kabylake. drm/i915: Add more Kabylake PCI IDs. drm/i915: Avoid early timeout during AUX transfers drm/i915/hsw: Avoid early timeout during LCPLL disable/restore drm/i915/lpt: Avoid early timeout during FDI PHY reset drm/i915/bxt: Avoid early timeout during PLL enable drm/i915: Refresh cached DP port register value on resume drm/amd/powerplay: Update CKS on/ CKS off voltage offset calculation drm/amd/powerplay: disable FFC. drm/amd/powerplay: add some definition for FFC feature on polaris.
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git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spiLinus Torvalds authored
Pull spi fixes from Mark Brown: "A few small driver-specific fixes for SPI, all in the normal important if you hit them category especially the rockchip driver fix which addresses a race which has been exposed more frequently with some recent performance improvements" * tag 'spi-fix-v4.7-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi: spi: sunxi: fix transfer timeout spi: sun4i: fix FIFO limit spi: rockchip: Signal unfinished DMA transfers spi: spi-ti-qspi: Suspend the queue before removing the device
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Linus Torvalds authored
Merge tag 'regulator-fix-v4.7-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator Pull regulator fixes from Mark Brown: "Two small fixes for the regulator subsystem - one fixing a crash with one of the devices supported by the max77620 driver, another fixing startup for the anatop regulator when it starts up with the regulator in bypass mode" * tag 'regulator-fix-v4.7-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator: regulator: max77620: check for valid regulator info regulator: anatop: allow regulator to be in bypass mode
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git://git.kernel.org/pub/scm/linux/kernel/git/clk/linuxLinus Torvalds authored
Pull clk fixes from Stephen Boyd: "A small fix for the newly added oxnas clk driver and a handful of rockchip clk driver fixes for newly added rk3399 support" * tag 'clk-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux: clk: Fix return value check in oxnas_stdclk_probe() clk: rockchip: release io resource when failing to init clk on rk3399 clk: rockchip: fix cpuclk registration error handling clk: rockchip: Revert "clk: rockchip: reset init state before mmc card initialization" clk: rockchip: fix incorrect parent for rk3399's {c,g}pll_aclk_perihp_src clk: rockchip: mark rk3399 GIC clocks as critical clk: rockchip: initialize flags of clk_init_data in mmc-phase clock
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git://anongit.freedesktop.org/drm-intelDave Airlie authored
here's a batch of i915 fixes for 4.7. * tag 'drm-intel-fixes-2016-06-30' of git://anongit.freedesktop.org/drm-intel: drm/i915: Fix missing unlock on error in i915_ppgtt_info() drm/i915: Removing PCI IDs that are no longer listed as Kabylake. drm/i915: Add more Kabylake PCI IDs. drm/i915: Avoid early timeout during AUX transfers drm/i915/hsw: Avoid early timeout during LCPLL disable/restore drm/i915/lpt: Avoid early timeout during FDI PHY reset drm/i915/bxt: Avoid early timeout during PLL enable drm/i915: Refresh cached DP port register value on resume
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git://people.freedesktop.org/~agd5f/linuxDave Airlie authored
Just a few more late fixes for Polaris cards. * 'drm-fixes-4.7' of git://people.freedesktop.org/~agd5f/linux: drm/amd/powerplay: workaround for UVD clock issue drm/amdgpu: add ACLK_CNTL setting for polaris10 drm/amd/powerplay: fix issue uvd dpm can't enabled on Polaris11. drm/amd/powerplay: Workaround for Memory EDC Error on Polaris10. drm/amd/powerplay: Update CKS on/ CKS off voltage offset calculation drm/amd/powerplay: disable FFC. drm/amd/powerplay: add some definition for FFC feature on polaris.
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