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path: root/fs/btrfs/send.c
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2017-10-30btrfs: Remove unused arguments from btrfs_changed_cb_tNikolay Borisov
btrfs_changed_cb_t represents the signature of the callback being passed to btrfs_compare_trees. Currently there is only one such callback, namely changed_cb in send.c. This function doesn't really uses the first 2 parameters, i.e. the roots. Since there are not other functions implementing the btrfs_changed_cb_t let's remove the unused parameters from the prototype and implementation. Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Reviewed-by: Josef Bacik <jbacik@fb.com> Signed-off-by: David Sterba <dsterba@suse.com>
2017-10-30btrfs: Remove unused parameters from various functionsNikolay Borisov
iterate_dir_item:found_key - introduced in 31db9f7c23fb ("Btrfs: introduce BTRFS_IOC_SEND for btrfs send/receive"), yet never used. record_ref:num - ditto This is a first pass with the low-hanging fruit. There are still quite a few unsued parameters in some function which have to abide by a callback interface. Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: Josef Bacik <jbacik@fb.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2017-09-29Merge branch 'for-4.14-rc3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux Pull btrfs fixes from David Sterba: "We've collected a bunch of isolated fixes, for crashes, user-visible behaviour or missing bits from other subsystem cleanups from the past. The overall number is not small but I was not able to make it significantly smaller. Most of the patches are supposed to go to stable" * 'for-4.14-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: btrfs: log csums for all modified extents Btrfs: fix unexpected result when dio reading corrupted blocks btrfs: Report error on removing qgroup if del_qgroup_item fails Btrfs: skip checksum when reading compressed data if some IO have failed Btrfs: fix kernel oops while reading compressed data Btrfs: use btrfs_op instead of bio_op in __btrfs_map_block Btrfs: do not backup tree roots when fsync btrfs: remove BTRFS_FS_QUOTA_DISABLING flag btrfs: propagate error to btrfs_cmp_data_prepare caller btrfs: prevent to set invalid default subvolid Btrfs: send: fix error number for unknown inode types btrfs: fix NULL pointer dereference from free_reloc_roots() btrfs: finish ordered extent cleaning if no progress is found btrfs: clear ordered flag on cleaning up ordered extents Btrfs: fix incorrect {node,sector}size endianness from BTRFS_IOC_FS_INFO Btrfs: do not reset bio->bi_ops while writing bio Btrfs: use the new helper wbc_to_write_flags
2017-09-26Btrfs: send: fix error number for unknown inode typesTsutomu Itoh
ENOTSUPP should not be returned to the user program. (cf. include/linux/errno.h) Therefore, EOPNOTSUPP is used instead of ENOTSUPP. Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2017-09-14Merge branch 'work.set_fs' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull more set_fs removal from Al Viro: "Christoph's 'use kernel_read and friends rather than open-coding set_fs()' series" * 'work.set_fs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: fs: unexport vfs_readv and vfs_writev fs: unexport vfs_read and vfs_write fs: unexport __vfs_read/__vfs_write lustre: switch to kernel_write gadget/f_mass_storage: stop messing with the address limit mconsole: switch to kernel_read btrfs: switch write_buf to kernel_write net/9p: switch p9_fd_read to kernel_write mm/nommu: switch do_mmap_private to kernel_read serial2002: switch serial2002_tty_write to kernel_{read/write} fs: make the buf argument to __kernel_write a void pointer fs: fix kernel_write prototype fs: fix kernel_read prototype fs: move kernel_read to fs/read_write.c fs: move kernel_write to fs/read_write.c autofs4: switch autofs4_write to __kernel_write ashmem: switch to ->read_iter
2017-09-04btrfs: switch write_buf to kernel_writeChristoph Hellwig
Instead of playing with the addressing limits. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-08-21Btrfs: incremental send, fix emission of invalid clone operationsFilipe Manana
When doing an incremental send it's possible that the computed send stream contains clone operations that will fail on the receiver if the receiver has compression enabled and the clone operations target a sector sized extent that starts at a zero file offset, is not compressed on the source filesystem but ends up being compressed and inlined at the destination filesystem. Example scenario: $ mkfs.btrfs -f /dev/sdb $ mount -o compress /dev/sdb /mnt # By doing a direct IO write, the data is not compressed. $ xfs_io -f -d -c "pwrite -S 0xab 0 4K" /mnt/foobar $ btrfs subvolume snapshot -r /mnt /mnt/mysnap1 $ xfs_io -c "reflink /mnt/foobar 0 8K 4K" /mnt/foobar $ btrfs subvolume snapshot -r /mnt /mnt/mysnap2 $ btrfs send -f /tmp/1.snap /mnt/mysnap1 $ btrfs send -f /tmp/2.snap -p /mnt/mysnap1 /mnt/mysnap2 $ umount /mnt $ mkfs.btrfs -f /dev/sdc $ mount -o compress /dev/sdc /mnt $ btrfs receive -f /tmp/1.snap /mnt $ btrfs receive -f /tmp/2.snap /mnt ERROR: failed to clone extents to foobar Operation not supported The same could be achieved by mounting the source filesystem without compression and doing a buffered IO write instead of a direct IO one, and mounting the destination filesystem with compression enabled. So fix this by issuing regular write operations in the send stream instead of clone operations when the source offset is zero and the range has a length matching the sector size. Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: Liu Bo <bo.li.liu@oracle.com> Signed-off-by: Chris Mason <clm@fb.com> Signed-off-by: David Sterba <dsterba@suse.com>
2017-08-16btrfs: remove trivial wrapper btrfs_force_raDavid Sterba
It's a simple call page_cache_sync_readahead, same arguments in the same order. Signed-off-by: David Sterba <dsterba@suse.com>
2017-07-06Btrfs: incremental send, fix invalid memory accessFilipe Manana
When doing an incremental send, while processing an extent that changed between the parent and send snapshots and that extent was an inline extent in the parent snapshot, it's possible to access a memory region beyond the end of leaf if the inline extent is very small and it is the first item in a leaf. An example scenario is described below. The send snapshot has the following leaf: leaf 33865728 items 33 free space 773 generation 46 owner 5 fs uuid ab7090d8-dafd-4fb9-9246-723b6d2e2fb7 chunk uuid 2d16478c-c704-4ab9-b574-68bff2281b1f (...) item 14 key (335 EXTENT_DATA 0) itemoff 3052 itemsize 53 generation 36 type 1 (regular) extent data disk byte 12791808 nr 4096 extent data offset 0 nr 4096 ram 4096 extent compression 0 (none) item 15 key (335 EXTENT_DATA 8192) itemoff 2999 itemsize 53 generation 36 type 1 (regular) extent data disk byte 138170368 nr 225280 extent data offset 0 nr 225280 ram 225280 extent compression 0 (none) (...) And the parent snapshot has the following leaf: leaf 31272960 items 17 free space 17 generation 31 owner 5 fs uuid ab7090d8-dafd-4fb9-9246-723b6d2e2fb7 chunk uuid 2d16478c-c704-4ab9-b574-68bff2281b1f item 0 key (335 EXTENT_DATA 0) itemoff 3951 itemsize 44 generation 31 type 0 (inline) inline extent data size 23 ram_bytes 613 compression 1 (zlib) (...) When computing the send stream, it is detected that the extent of inode 335, at file offset 0, and at fs/btrfs/send.c:is_extent_unchanged() we grab the leaf from the parent snapshot and access the inline extent item. However, before jumping to the 'out' label, we access the 'offset' and 'disk_bytenr' fields of the extent item, which should not be done for inline extents since the inlined data starts at the offset of the 'disk_bytenr' field and can be very small. For example accessing the 'offset' field of the file extent item results in the following trace: [ 599.705368] general protection fault: 0000 [#1] PREEMPT SMP [ 599.706296] Modules linked in: btrfs psmouse i2c_piix4 ppdev acpi_cpufreq serio_raw parport_pc i2c_core evdev tpm_tis tpm_tis_core sg pcspkr parport tpm button su$ [ 599.709340] CPU: 7 PID: 5283 Comm: btrfs Not tainted 4.10.0-rc8-btrfs-next-46+ #1 [ 599.709340] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.9.1-0-gb3ef39f-prebuilt.qemu-project.org 04/01/2014 [ 599.709340] task: ffff88023eedd040 task.stack: ffffc90006658000 [ 599.709340] RIP: 0010:read_extent_buffer+0xdb/0xf4 [btrfs] [ 599.709340] RSP: 0018:ffffc9000665ba00 EFLAGS: 00010286 [ 599.709340] RAX: db73880000000000 RBX: 0000000000000000 RCX: 0000000000000001 [ 599.709340] RDX: ffffc9000665ba60 RSI: db73880000000000 RDI: ffffc9000665ba5f [ 599.709340] RBP: ffffc9000665ba30 R08: 0000000000000001 R09: ffff88020dc5e098 [ 599.709340] R10: 0000000000001000 R11: 0000160000000000 R12: 6db6db6db6db6db7 [ 599.709340] R13: ffff880000000000 R14: 0000000000000000 R15: ffff88020dc5e088 [ 599.709340] FS: 00007f519555a8c0(0000) GS:ffff88023f3c0000(0000) knlGS:0000000000000000 [ 599.709340] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 599.709340] CR2: 00007f1411afd000 CR3: 0000000235f8e000 CR4: 00000000000006e0 [ 599.709340] Call Trace: [ 599.709340] btrfs_get_token_64+0x93/0xce [btrfs] [ 599.709340] ? printk+0x48/0x50 [ 599.709340] btrfs_get_64+0xb/0xd [btrfs] [ 599.709340] process_extent+0x3a1/0x1106 [btrfs] [ 599.709340] ? btree_read_extent_buffer_pages+0x5/0xef [btrfs] [ 599.709340] changed_cb+0xb03/0xb3d [btrfs] [ 599.709340] ? btrfs_get_token_32+0x7a/0xcc [btrfs] [ 599.709340] btrfs_compare_trees+0x432/0x53d [btrfs] [ 599.709340] ? process_extent+0x1106/0x1106 [btrfs] [ 599.709340] btrfs_ioctl_send+0x960/0xe26 [btrfs] [ 599.709340] btrfs_ioctl+0x181b/0x1fed [btrfs] [ 599.709340] ? trace_hardirqs_on_caller+0x150/0x1ac [ 599.709340] vfs_ioctl+0x21/0x38 [ 599.709340] ? vfs_ioctl+0x21/0x38 [ 599.709340] do_vfs_ioctl+0x611/0x645 [ 599.709340] ? rcu_read_unlock+0x5b/0x5d [ 599.709340] ? __fget+0x6d/0x79 [ 599.709340] SyS_ioctl+0x57/0x7b [ 599.709340] entry_SYSCALL_64_fastpath+0x18/0xad [ 599.709340] RIP: 0033:0x7f51945eec47 [ 599.709340] RSP: 002b:00007ffc21c13e98 EFLAGS: 00000202 ORIG_RAX: 0000000000000010 [ 599.709340] RAX: ffffffffffffffda RBX: ffffffff81096459 RCX: 00007f51945eec47 [ 599.709340] RDX: 00007ffc21c13f20 RSI: 0000000040489426 RDI: 0000000000000004 [ 599.709340] RBP: ffffc9000665bf98 R08: 00007f519450d700 R09: 00007f519450d700 [ 599.709340] R10: 00007f519450d9d0 R11: 0000000000000202 R12: 0000000000000046 [ 599.709340] R13: ffffc9000665bf78 R14: 0000000000000000 R15: 00007f5195574040 [ 599.709340] ? trace_hardirqs_off_caller+0x43/0xb1 [ 599.709340] Code: 29 f0 49 39 d8 4c 0f 47 c3 49 03 81 58 01 00 00 44 89 c1 4c 01 c2 4c 29 c3 48 c1 f8 03 49 0f af c4 48 c1 e0 0c 4c 01 e8 48 01 c6 <f3> a4 31 f6 4$ [ 599.709340] RIP: read_extent_buffer+0xdb/0xf4 [btrfs] RSP: ffffc9000665ba00 [ 599.762057] ---[ end trace fe00d7af61b9f49e ]--- This is because the 'offset' field starts at an offset of 37 bytes (offsetof(struct btrfs_file_extent_item, offset)), has a length of 8 bytes and therefore attemping to read it causes a 1 byte access beyond the end of the leaf, as the first item's content in a leaf is located at the tail of the leaf, the item size is 44 bytes and the offset of that field plus its length (37 + 8 = 45) goes beyond the item's size by 1 byte. So fix this by accessing the 'offset' and 'disk_bytenr' fields after jumping to the 'out' label if we are processing an inline extent. We move the reading operation of the 'disk_bytenr' field too because we have the same problem as for the 'offset' field explained above when the inline data is less then 8 bytes. The access to the 'generation' field is also moved but just for the sake of grouping access to all the fields. Fixes: e1cbfd7bf6da ("Btrfs: send, fix file hole not being preserved due to inline extent") Cc: <stable@vger.kernel.org> # v4.12+ Signed-off-by: Filipe Manana <fdmanana@suse.com>
2017-07-06Btrfs: incremental send, fix invalid path for link commandsFilipe Manana
In some scenarios an incremental send stream can contain link commands with an invalid target path. Such scenarios happen after moving some directory inode A, renaming a regular file inode B into the old name of inode A and finally creating a new hard link for inode B at directory inode A. Consider the following example scenario where this issue happens. Parent snapshot: . (ino 256) | |--- dir1/ (ino 257) | |--- dir2/ (ino 258) | |--- dir3/ (ino 259) | |--- file1 (ino 261) | |--- dir4/ (ino 262) | |--- dir5/ (ino 260) Send snapshot: . (ino 256) | |--- dir1/ (ino 257) |--- dir2/ (ino 258) | |--- dir3/ (ino 259) | |--- dir4 (ino 261) | |--- dir6/ (ino 263) |--- dir44/ (ino 262) |--- file11 (ino 261) |--- dir55/ (ino 260) When attempting to apply the corresponding incremental send stream, a link command contains an invalid target path which makes the receiver fail. The following is the verbose output of the btrfs receive command: receiving snapshot mysnap2 uuid=90076fe6-5ba6-e64a-9321-9279670ed16b (...) utimes utimes dir1 utimes dir1/dir2/dir3 utimes rename dir1/dir2/dir3/dir4 -> o262-7-0 link dir1/dir2/dir3/dir4 -> dir1/dir2/dir3/file1 link dir1/dir2/dir3/dir4/file11 -> dir1/dir2/dir3/file1 ERROR: link dir1/dir2/dir3/dir4/file11 -> dir1/dir2/dir3/file1 failed: Not a directory The following steps happen during the computation of the incremental send stream the lead to this issue: 1) When processing inode 261, we orphanize inode 262 due to a name/location collision with one of the new hard links for inode 261 (created in the second step below). 2) We create one of the 2 new hard links for inode 261, the one whose location is at "dir1/dir2/dir3/dir4". 3) We then attempt to create the other new hard link for inode 261, which has inode 262 as its parent directory. Because the path for this new hard link was computed before we started processing the new references (hard links), it reflects the old name/location of inode 262, that is, it does not account for the orphanization step that happened when we started processing the new references for inode 261, whence it is no longer valid, causing the receiver to fail. So fix this issue by recomputing the full path of new references if we ended up orphanizing other inodes which are directories. A test case for fstests follows soon. Signed-off-by: Filipe Manana <fdmanana@suse.com>
2017-06-21btrfs: Check name_len before read in iterate_dir_itemSu Yue
Since iterate_dir_item checks name_len in its own way, so use btrfs_is_name_len_valid not 'verify_dir_item' to make more strict name_len check. Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com> Reviewed-by: David Sterba <dsterba@suse.com> [ switched ENAMETOOLONG to EIO ] Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-21Btrfs: incremental send, fix invalid path for unlink commandsFilipe Manana
An incremental send can contain unlink operations with an invalid target path when we rename some directory inode A, then rename some file inode B to the old name of inode A and directory inode A is an ancestor of inode B in the parent snapshot (but not anymore in the send snapshot). Consider the following example scenario where this issue happens. Parent snapshot: . (ino 256) | |--- dir1/ (ino 257) |--- dir2/ (ino 258) | |--- file1 (ino 259) | |--- file3 (ino 261) | |--- dir3/ (ino 262) |--- file22 (ino 260) |--- dir4/ (ino 263) Send snapshot: . (ino 256) | |--- dir1/ (ino 257) |--- dir2/ (ino 258) |--- dir3 (ino 260) |--- file3/ (ino 262) |--- dir4/ (ino 263) |--- file11 (ino 269) |--- file33 (ino 261) When attempting to apply the corresponding incremental send stream, an unlink operation contains an invalid path which makes the receiver fail. The following is verbose output of the btrfs receive command: receiving snapshot snap2 uuid=7d5450da-a573-e043-a451-ec85f4879f0f (...) utimes utimes dir1 utimes dir1/dir2 link dir1/dir3/dir4/file11 -> dir1/dir2/file1 unlink dir1/dir2/file1 utimes dir1/dir2 truncate dir1/dir3/dir4/file11 size=0 utimes dir1/dir3/dir4/file11 rename dir1/dir3 -> o262-7-0 link dir1/dir3 -> o262-7-0/file22 unlink dir1/dir3/file22 ERROR: unlink dir1/dir3/file22 failed. Not a directory The following steps happen during the computation of the incremental send stream the lead to this issue: 1) Before we start processing the new and deleted references for inode 260, we compute the full path of the deleted reference ("dir1/dir3/file22") and cache it in the list of deleted references for our inode. 2) We then start processing the new references for inode 260, for which there is only one new, located at "dir1/dir3". When processing this new reference, we check that inode 262, which was not yet processed, collides with the new reference and because of that we orphanize inode 262 so its new full path becomes "o262-7-0". 3) After the orphanization of inode 262, we create the new reference for inode 260 by issuing a link command with a target path of "dir1/dir3" and a source path of "o262-7-0/file22". 4) We then start processing the deleted references for inode 260, for which there is only one with the base name of "file22", and issue an unlink operation containing the target path computed at step 1, which is wrong because that path no longer exists and should be replaced with "o262-7-0/file22". So fix this issue by recomputing the full path of deleted references if when we processed the new references for an inode we ended up orphanizing any other inode that is an ancestor of our inode in the parent snapshot. A test case for fstests follows soon. Signed-off-by: Filipe Manana <fdmanana@suse.com> [ adjusted after prev patch removed fs_path::dir_path and dir_path_len ] Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-21Btrfs: send, fix invalid path after renaming and linking fileFilipe Manana
Currently an incremental snapshot can generate link operations which contain an invalid target path. Such case happens when in the send snapshot a file was renamed, a new hard link added for it and some other inode (with a lower number) got renamed to the former name of that file. Example: Parent snapshot . (ino 256) | |--- f1 (ino 257) |--- f2 (ino 258) |--- f3 (ino 259) Send snapshot . (ino 256) | |--- f2 (ino 257) |--- f3 (ino 258) |--- f4 (ino 259) |--- f5 (ino 258) The following steps happen when computing the incremental send stream: 1) When processing inode 257, inode 258 is orphanized (renamed to "o258-7-0"), because its current reference has the same name as the new reference for inode 257; 2) When processing inode 258, we iterate over all its new references, which have the names "f3" and "f5". The first iteration sees name "f5" and renames the inode from its orphan name ("o258-7-0") to "f5", while the second iteration sees the name "f3" and, incorrectly, issues a link operation with a target name matching the orphan name, which no longer exists. The first iteration had reset the current valid path of the inode to "f5", but in the second iteration we lost it because we found another inode, with a higher number of 259, which has a reference named "f3" as well, so we orphanized inode 259 and recomputed the current valid path of inode 258 to its old orphan name because inode 259 could be an ancestor of inode 258 and therefore the current valid path could contain the pre-orphanization name of inode 259. However in this case inode 259 is not an ancestor of inode 258 so the current valid path should not be recomputed. This makes the receiver fail with the following error: ERROR: link f3 -> o258-7-0 failed: No such file or directory So fix this by not recomputing the current valid path for an inode whenever we find a colliding reference from some not yet processed inode (inode number higher then the one currently being processed), unless that other inode is an ancestor of the one we are currently processing. A test case for fstests will follow soon. Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-19btrfs: send: use kvmalloc in iterate_dir_itemDavid Sterba
We use a growing buffer for xattrs larger than a page size, at some point vmalloc is unconditionally used for larger buffers. We can still try to avoid it using the kvmalloc helper. Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-19btrfs: replace opencoded kvzalloc with the helperDavid Sterba
The logic of kmalloc and vmalloc fallback is opencoded in several places, we can now use the existing helper. Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-19btrfs: remove unused members dir_path from recorded_refDavid Sterba
The two members do not seem to be used since the initial commit. Signed-off-by: David Sterba <dsterba@suse.com>
2017-05-10Merge branch 'for-linus-4.12' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs Pull btrfs updates from Chris Mason: "This has fixes and cleanups Dave Sterba collected for the merge window. The biggest functional fixes are between btrfs raid5/6 and scrub, and raid5/6 and device replacement. Some of our pending qgroup fixes are included as well while I bash on the rest in testing. We also have the usual set of cleanups, including one that makes __btrfs_map_block() much more maintainable, and conversions from atomic_t to refcount_t" * 'for-linus-4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (71 commits) btrfs: fix the gfp_mask for the reada_zones radix tree Btrfs: fix reported number of inode blocks Btrfs: send, fix file hole not being preserved due to inline extent Btrfs: fix extent map leak during fallocate error path Btrfs: fix incorrect space accounting after failure to insert inline extent Btrfs: fix invalid attempt to free reserved space on failure to cow range btrfs: Handle delalloc error correctly to avoid ordered extent hang btrfs: Fix metadata underflow caused by btrfs_reloc_clone_csum error btrfs: check if the device is flush capable btrfs: delete unused member nobarriers btrfs: scrub: Fix RAID56 recovery race condition btrfs: scrub: Introduce full stripe lock for RAID56 btrfs: Use ktime_get_real_ts for root ctime Btrfs: handle only applicable errors returned by btrfs_get_extent btrfs: qgroup: Fix qgroup corruption caused by inode_cache mount option btrfs: use q which is already obtained from bdev_get_queue Btrfs: switch to div64_u64 if with a u64 divisor Btrfs: update scrub_parity to use u64 stripe_len Btrfs: enable repair during read for raid56 profile btrfs: use clear_page where appropriate ...
2017-05-08treewide: use kv[mz]alloc* rather than opencoded variantsMichal Hocko
There are many code paths opencoding kvmalloc. Let's use the helper instead. The main difference to kvmalloc is that those users are usually not considering all the aspects of the memory allocator. E.g. allocation requests <= 32kB (with 4kB pages) are basically never failing and invoke OOM killer to satisfy the allocation. This sounds too disruptive for something that has a reasonable fallback - the vmalloc. On the other hand those requests might fallback to vmalloc even when the memory allocator would succeed after several more reclaim/compaction attempts previously. There is no guarantee something like that happens though. This patch converts many of those places to kv[mz]alloc* helpers because they are more conservative. Link: http://lkml.kernel.org/r/20170306103327.2766-2-mhocko@kernel.org Signed-off-by: Michal Hocko <mhocko@suse.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> # Xen bits Acked-by: Kees Cook <keescook@chromium.org> Acked-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Andreas Dilger <andreas.dilger@intel.com> # Lustre Acked-by: Christian Borntraeger <borntraeger@de.ibm.com> # KVM/s390 Acked-by: Dan Williams <dan.j.williams@intel.com> # nvdim Acked-by: David Sterba <dsterba@suse.com> # btrfs Acked-by: Ilya Dryomov <idryomov@gmail.com> # Ceph Acked-by: Tariq Toukan <tariqt@mellanox.com> # mlx4 Acked-by: Leon Romanovsky <leonro@mellanox.com> # mlx5 Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Anton Vorontsov <anton@enomsg.org> Cc: Colin Cross <ccross@android.com> Cc: Tony Luck <tony.luck@intel.com> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Ben Skeggs <bskeggs@redhat.com> Cc: Kent Overstreet <kent.overstreet@gmail.com> Cc: Santosh Raspatur <santosh@chelsio.com> Cc: Hariprasad S <hariprasad@chelsio.com> Cc: Yishai Hadas <yishaih@mellanox.com> Cc: Oleg Drokin <oleg.drokin@intel.com> Cc: "Yan, Zheng" <zyan@redhat.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: David Miller <davem@davemloft.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-04-26Btrfs: send, fix file hole not being preserved due to inline extentFilipe Manana
Normally we don't have inline extents followed by regular extents, but there's currently at least one harmless case where this happens. For example, when the page size is 4Kb and compression is enabled: $ mkfs.btrfs -f /dev/sdb $ mount -o compress /dev/sdb /mnt $ xfs_io -f -c "pwrite -S 0xaa 0 4K" -c "fsync" /mnt/foobar $ xfs_io -c "pwrite -S 0xbb 8K 4K" -c "fsync" /mnt/foobar In this case we get a compressed inline extent, representing 4Kb of data, followed by a hole extent and then a regular data extent. The inline extent was not expanded/converted to a regular extent exactly because it represents 4Kb of data. This does not cause any apparent problem (such as the issue solved by commit e1699d2d7bf6 ("btrfs: add missing memset while reading compressed inline extents")) except trigger an unexpected case in the incremental send code path that makes us issue an operation to write a hole when it's not needed, resulting in more writes at the receiver and wasting space at the receiver. So teach the incremental send code to deal with this particular case. The issue can be currently triggered by running fstests btrfs/137 with compression enabled (MOUNT_OPTIONS="-o compress" ./check btrfs/137). Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
2017-03-29Btrfs: fix an integer overflow checkDan Carpenter
This isn't super serious because you need CAP_ADMIN to run this code. I added this integer overflow check last year but apparently I am rubbish at writing integer overflow checks... There are two issues. First, access_ok() works on unsigned long type and not u64 so on 32 bit systems the access_ok() could be checking a truncated size. The other issue is that we should be using a stricter limit so we don't overflow the kzalloc() setting ctx->clone_roots later in the function after the access_ok(): alloc_size = sizeof(struct clone_root) * (arg->clone_sources_count + 1); sctx->clone_roots = kzalloc(alloc_size, GFP_KERNEL | __GFP_NOWARN); Fixes: f5ecec3ce21f ("btrfs: send: silence an integer overflow warning") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Reviewed-by: David Sterba <dsterba@suse.com> [ added comment ] Signed-off-by: David Sterba <dsterba@suse.com>
2017-02-24Btrfs: incremental send, fix unnecessary hole writes for sparse filesFilipe Manana
When using the NO_HOLES feature, during an incremental send we often issue write operations for holes when we should not, because that range is already a hole in the destination snapshot. While that does not change the contents of the file at the receiver, it avoids preservation of file holes, leading to wasted disk space and extra IO during send/receive. A couple examples where the holes are not preserved follows. $ mkfs.btrfs -O no-holes -f /dev/sdb $ mount /dev/sdb /mnt $ xfs_io -f -c "pwrite -S 0xaa 0 4K" /mnt/foo $ xfs_io -f -c "pwrite -S 0xaa 0 4K" -c "pwrite -S 0xbb 1028K 4K" /mnt/bar $ btrfs subvolume snapshot -r /mnt /mnt/snap1 # Now add one new extent to our first test file, increasing its size and # leaving a 1Mb hole between the first extent and this new extent. $ xfs_io -c "pwrite -S 0xbb 1028K 4K" /mnt/foo # Now overwrite the last extent of our second test file. $ xfs_io -c "pwrite -S 0xcc 1028K 4K" /mnt/bar $ btrfs subvolume snapshot -r /mnt /mnt/snap2 $ xfs_io -r -c "fiemap -v" /mnt/snap2/foo /mnt/snap2/foo: EXT: FILE-OFFSET BLOCK-RANGE TOTAL FLAGS 0: [0..7]: 25088..25095 8 0x2000 1: [8..2055]: hole 2048 2: [2056..2063]: 24576..24583 8 0x2001 $ xfs_io -r -c "fiemap -v" /mnt/snap2/bar /mnt/snap2/bar: EXT: FILE-OFFSET BLOCK-RANGE TOTAL FLAGS 0: [0..7]: 25096..25103 8 0x2000 1: [8..2055]: hole 2048 2: [2056..2063]: 24584..24591 8 0x2001 $ btrfs send /mnt/snap1 -f /tmp/1.snap $ btrfs send -p /mnt/snap1 /mnt/snap2 -f /tmp/2.snap $ umount /mnt # It's not relevant to enable no-holes in the new filesystem. $ mkfs.btrfs -O no-holes -f /dev/sdc $ mount /dev/sdc /mnt $ btrfs receive /mnt -f /tmp/1.snap $ btrfs receive /mnt -f /tmp/2.snap $ xfs_io -r -c "fiemap -v" /mnt/snap2/foo /mnt/snap2/foo: EXT: FILE-OFFSET BLOCK-RANGE TOTAL FLAGS 0: [0..7]: 24576..24583 8 0x2000 1: [8..2063]: 25624..27679 2056 0x1 $ xfs_io -r -c "fiemap -v" /mnt/snap2/bar /mnt/snap2/bar: EXT: FILE-OFFSET BLOCK-RANGE TOTAL FLAGS 0: [0..7]: 24584..24591 8 0x2000 1: [8..2063]: 27680..29735 2056 0x1 The holes do not exist in the second filesystem and they were replaced with extents filled with the byte 0x00, making each file take 1032Kb of space instead of 8Kb. So fix this by not issuing the write operations consisting of buffers filled with the byte 0x00 when the destination snapshot already has a hole for the respective range. A test case for fstests will follow soon. Signed-off-by: Filipe Manana <fdmanana@suse.com>
2017-02-24Btrfs: incremental send, do not issue invalid rmdir operationsRobbie Ko
When both the parent and send snapshots have a directory inode with the same number but different generations (therefore they are different inodes) and both have an entry with the same name, an incremental send stream will contain an invalid rmdir operation that refers to the orphanized name of the inode from the parent snapshot. The following example scenario shows how this happens. Parent snapshot: . |---- d259_old/ (ino 259, gen 9) | |---- d1/ (ino 258, gen 9) | |---- f (ino 257, gen 9) Send snapshot: . |---- d258/ (ino 258, gen 7) |---- d259/ (ino 259, gen 7) |---- d1/ (ino 257, gen 7) When the kernel is processing inode 258 it notices that in both snapshots there is an inode numbered 259 that is a parent of an inode 258. However it ignores the fact that the inodes numbered 259 have different generations in both snapshots, which means they are effectively different inodes. Then it checks that both inodes 259 have a dentry named "d1" and because of that it issues a rmdir operation with orphanized name of the inode 258 from the parent snapshot. This happens at send.c:process_record_refs(), which calls send.c:did_overwrite_first_ref() that returns true and because of that later on at process_recorded_refs() such rmdir operation is issued because the inode being currently processed (258) is a directory and it was deleted in the send snapshot (and replaced with another inode that has the same number and is a directory too). Fix this issue by comparing the generations of parent directory inodes that have the same number and make send.c:did_overwrite_first_ref() when the generations are different. The following steps reproduce the problem. $ mkfs.btrfs -f /dev/sdb $ mount /dev/sdb /mnt $ touch /mnt/f $ mkdir /mnt/d1 $ mkdir /mnt/d259_old $ mv /mnt/d1 /mnt/d259_old/d1 $ btrfs subvolume snapshot -r /mnt /mnt/snap1 $ btrfs send /mnt/snap1 -f /tmp/1.snap $ umount /mnt $ mkfs.btrfs -f /dev/sdc $ mount /dev/sdc /mnt $ mkdir /mnt/d1 $ mkdir /mnt/dir258 $ mkdir /mnt/dir259 $ mv /mnt/d1 /mnt/dir259/d1 $ btrfs subvolume snapshot -r /mnt /mnt/snap2 $ btrfs receive /mnt/ -f /tmp/1.snap # Take note that once the filesystem is created, its current # generation has value 7 so the inodes from the second snapshot all have # a generation value of 7. And after receiving the first snapshot # the filesystem is at a generation value of 10, because the call to # create the second snapshot bumps the generation to 8 (the snapshot # creation ioctl does a transaction commit), the receive command calls # the snapshot creation ioctl to create the first snapshot, which bumps # the filesystem's generation to 9, and finally when the receive # operation finishes it calls an ioctl to transition the first snapshot # (snap1) from RW mode to RO mode, which does another transaction commit # and bumps the filesystem's generation to 10. This means all the inodes # in the first snapshot (snap1) have a generation value of 9. $ rm -f /tmp/1.snap $ btrfs send /mnt/snap1 -f /tmp/1.snap $ btrfs send -p /mnt/snap1 /mnt/snap2 -f /tmp/2.snap $ umount /mnt $ mkfs.btrfs -f /dev/sdd $ mount /dev/sdd /mnt $ btrfs receive /mnt -f /tmp/1.snap $ btrfs receive -vv /mnt -f /tmp/2.snap receiving snapshot mysnap2 uuid=9c03962f-f620-0047-9f98-32e5a87116d9, ctransid=7 parent_uuid=d17a6e3f-14e5-df4f-be39-a7951a5399aa, parent_ctransid=9 utimes unlink f mkdir o257-7-0 mkdir o259-7-0 rename o257-7-0 -> o259-7-0/d1 chown o259-7-0/d1 - uid=0, gid=0 chmod o259-7-0/d1 - mode=0755 utimes o259-7-0/d1 rmdir o258-9-0 ERROR: rmdir o258-9-0 failed: No such file or directory Signed-off-by: Robbie Ko <robbieko@synology.com> Reviewed-by: Filipe Manana <fdmanana@suse.com> [Rewrote changelog to be more precise and clear] Signed-off-by: Filipe Manana <fdmanana@suse.com>
2017-02-24Btrfs: incremental send, do not delay rename when parent inode is newFilipe Manana
When we are checking if we need to delay the rename operation for an inode we not checking if a parent inode that exists in the send and parent snapshots is really the same inode or not, that is, we are not comparing the generation number of the parent inode in the send and parent snapshots. Not only this results in unnecessarily delaying a rename operation but also can later on make us generate an incorrect name for a new inode in the send snapshot that has the same number as another inode in the parent snapshot but a different generation. Here follows an example where this happens. Parent snapshot: . (ino 256, gen 3) |--- dir258/ (ino 258, gen 7) | |--- dir257/ (ino 257, gen 7) | |--- dir259/ (ino 259, gen 7) Send snapshot: . (ino 256, gen 3) |--- file258 (ino 258, gen 10) | |--- new_dir259/ (ino 259, gen 10) |--- dir257/ (ino 257, gen 7) The following steps happen when computing the incremental send stream: 1) When processing inode 257, its new parent is created using its orphan name (o257-21-0), and the rename operation for inode 257 is delayed because its new parent (inode 259) was not yet processed - this decision to delay the rename operation does not make much sense because the inode 259 in the send snapshot is a new inode, it's not the same as inode 259 in the parent snapshot. 2) When processing inode 258 we end up delaying its rmdir operation, because inode 257 was not yet renamed (moved away from the directory inode 258 represents). We also create the new inode 258 using its orphan name "o258-10-0", then rename it to its final name of "file258" and then issue a truncate operation for it. However this truncate operation contains an incorrect name, which corresponds to the orphan name and not to the final name, which makes the receiver fail. This happens because when we attempt to compute the inode's current name we verify that there's another inode with the same number (258) that has its rmdir operation pending and because of that we generate an orphan name for the new inode 258 (we do this in the function get_cur_path()). Fix this by not delayed the rename operation of an inode if it has parents with the same number but different generations in both snapshots. The following steps reproduce this example scenario. $ mkfs.btrfs -f /dev/sdb $ mount /dev/sdb /mnt $ mkdir /mnt/dir257 $ mkdir /mnt/dir258 $ mkdir /mnt/dir259 $ mv /mnt/dir257 /mnt/dir258/dir257 $ btrfs subvolume snapshot -r /mnt /mnt/snap1 $ mv /mnt/dir258/dir257 /mnt/dir257 $ rmdir /mnt/dir258 $ rmdir /mnt/dir259 # Remount the filesystem so that the next created inodes will have the # numbers 258 and 259. This is because when a filesystem is mounted, # btrfs sets the subvolume's inode counter to a value corresponding to # the highest inode number in the subvolume plus 1. This inode counter # is used to assign a unique number to each new inode and it's # incremented by 1 after very inode creation. # Note: we unmount and then mount instead of doing a mount with # "-o remount" because otherwise the inode counter remains at value 260. $ umount /mnt $ mount /dev/sdb /mnt $ touch /mnt/file258 $ mkdir /mnt/new_dir259 $ mv /mnt/dir257 /mnt/new_dir259/dir257 $ btrfs subvolume snapshot -r /mnt /mnt/snap2 $ btrfs send /mnt/snap1 -f /tmp/1.snap $ btrfs send -p /mnt/snap1 /mnt/snap2 -f /tmp/2.snap $ umount /mnt $ mkfs.btrfs -f /dev/sdc $ mount /dev/sdc /mnt $ btrfs receive /mnt -f /tmo/1.snap $ btrfs receive /mnt -f /tmo/2.snap -vv receiving snapshot mysnap2 uuid=e059b6d1-7f55-f140-8d7c-9a3039d23c97, ctransid=10 parent_uuid=77e98cb6-8762-814f-9e05-e8ba877fc0b0, parent_ctransid=7 utimes mkdir o259-10-0 rename dir258 -> o258-7-0 utimes mkfile o258-10-0 rename o258-10-0 -> file258 utimes truncate o258-10-0 size=0 ERROR: truncate o258-10-0 failed: No such file or directory Reported-by: Robbie Ko <robbieko@synology.com> Signed-off-by: Filipe Manana <fdmanana@suse.com>
2017-02-24Btrfs: send, fix failure to rename top level inode due to name collisionRobbie Ko
Under certain situations, an incremental send operation can fail due to a premature attempt to create a new top level inode (a direct child of the subvolume/snapshot root) whose name collides with another inode that was removed from the send snapshot. Consider the following example scenario. Parent snapshot: . (ino 256, gen 8) |---- a1/ (ino 257, gen 9) |---- a2/ (ino 258, gen 9) Send snapshot: . (ino 256, gen 3) |---- a2/ (ino 257, gen 7) In this scenario, when receiving the incremental send stream, the btrfs receive command fails like this (ran in verbose mode, -vv argument): rmdir a1 mkfile o257-7-0 rename o257-7-0 -> a2 ERROR: rename o257-7-0 -> a2 failed: Is a directory What happens when computing the incremental send stream is: 1) An operation to remove the directory with inode number 257 and generation 9 is issued. 2) An operation to create the inode with number 257 and generation 7 is issued. This creates the inode with an orphanized name of "o257-7-0". 3) An operation rename the new inode 257 to its final name, "a2", is issued. This is incorrect because inode 258, which has the same name and it's a child of the same parent (root inode 256), was not yet processed and therefore no rmdir operation for it was yet issued. The rename operation is issued because we fail to detect that the name of the new inode 257 collides with inode 258, because their parent, a subvolume/snapshot root (inode 256) has a different generation in both snapshots. So fix this by ignoring the generation value of a parent directory that matches a root inode (number 256) when we are checking if the name of the inode currently being processed collides with the name of some other inode that was not yet processed. We can achieve this scenario of different inodes with the same number but different generation values either by mounting a filesystem with the inode cache option (-o inode_cache) or by creating and sending snapshots across different filesystems, like in the following example: $ mkfs.btrfs -f /dev/sdb $ mount /dev/sdb /mnt $ mkdir /mnt/a1 $ mkdir /mnt/a2 $ btrfs subvolume snapshot -r /mnt /mnt/snap1 $ btrfs send /mnt/snap1 -f /tmp/1.snap $ umount /mnt $ mkfs.btrfs -f /dev/sdc $ mount /dev/sdc /mnt $ touch /mnt/a2 $ btrfs subvolume snapshot -r /mnt /mnt/snap2 $ btrfs receive /mnt -f /tmp/1.snap # Take note that once the filesystem is created, its current # generation has value 7 so the inode from the second snapshot has # a generation value of 7. And after receiving the first snapshot # the filesystem is at a generation value of 10, because the call to # create the second snapshot bumps the generation to 8 (the snapshot # creation ioctl does a transaction commit), the receive command calls # the snapshot creation ioctl to create the first snapshot, which bumps # the filesystem's generation to 9, and finally when the receive # operation finishes it calls an ioctl to transition the first snapshot # (snap1) from RW mode to RO mode, which does another transaction commit # and bumps the filesystem's generation to 10. $ rm -f /tmp/1.snap $ btrfs send /mnt/snap1 -f /tmp/1.snap $ btrfs send -p /mnt/snap1 /mnt/snap2 -f /tmp/2.snap $ umount /mnt $ mkfs.btrfs -f /dev/sdd $ mount /dev/sdd /mnt $ btrfs receive /mnt /tmp/1.snap # Receive of snapshot snap2 used to fail. $ btrfs receive /mnt /tmp/2.snap Signed-off-by: Robbie Ko <robbieko@synology.com> Reviewed-by: Filipe Manana <fdmanana@suse.com> [Rewrote changelog to be more precise and clear] Signed-off-by: Filipe Manana <fdmanana@suse.com>
2016-12-06btrfs: remove root parameter from transaction commit/end routinesJeff Mahoney
Now we only use the root parameter to print the root objectid in a tracepoint. We can use the root parameter from the transaction handle for that. It's also used to join the transaction with async commits, so we remove the comment that it's just for checking. Signed-off-by: Jeff Mahoney <jeffm@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2016-12-06btrfs: take an fs_info directly when the root is not used otherwiseJeff Mahoney
There are loads of functions in btrfs that accept a root parameter but only use it to obtain an fs_info pointer. Let's convert those to just accept an fs_info pointer directly. Signed-off-by: Jeff Mahoney <jeffm@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2016-12-06btrfs: root->fs_info cleanup, add fs_info convenience variablesJeff Mahoney
In routines where someptr->fs_info is referenced multiple times, we introduce a convenience variable. This makes the code considerably more readable. Signed-off-by: Jeff Mahoney <jeffm@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2016-12-06btrfs: pull node/sector/stripe sizes out of root and into fs_infoJeff Mahoney
We track the node sizes per-root, but they never vary from the values in the superblock. This patch messes with the 80-column style a bit, but subsequent patches to factor out root->fs_info into a convenience variable fix it up again. Signed-off-by: Jeff Mahoney <jeffm@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2016-10-28Merge branch 'for-linus-4.9' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs Pull btrfs fixes from Chris Mason: "My patch fixes the btrfs list_head abuse that we tracked down during Dave Jones' memory corruption investigation. With both Jens and my patches in place, I'm no longer able to trigger problems. Filipe is fixing a difficult old bug between snapshots, balance and send. Dave is cooking a few more for the next rc, but these are tested and ready" * 'for-linus-4.9' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: btrfs: fix races on root_log_ctx lists btrfs: fix incremental send failure caused by balance
2016-10-12Btrfs: fix incremental send failure caused by balanceFilipe Manana
Commit 951555856b88 ("Btrfs: send, don't bug on inconsistent snapshots") removed some BUG_ON() statements (replacing them with returning errors to user space and logging error messages) when a snapshot is in an inconsistent state due to failures to update a delayed inode item (ENOMEM or ENOSPC) after adding/updating/deleting references, xattrs or file extent items. However there is a case, when no errors happen, where a file extent item can be modified without having the corresponding inode item updated. This case happens during balance under very specific timings, when relocation is in the stage where it updates data pointers and a leaf that contains file extent items is COWed. When that happens file extent items get their disk_bytenr field updated to a new value that reflects the post relocation logical address of the extent, without updating their respective inode items (as there is nothing that needs to be updated on them). This is performed at relocation.c:replace_file_extents() through relocation.c:btrfs_reloc_cow_block(). So make an incremental send deal with this case and don't do any processing for a file extent item that got its disk_bytenr field updated by relocation, since the extent's data is the same as the one pointed by the file extent item in the parent snapshot. After the recent commit mentioned above this case resulted in EIO errors returned to user space (and an error message logged to dmesg/syslog) when doing an incremental send, while before it, it resulted in hitting a BUG_ON leading to the following trace: [ 952.206705] ------------[ cut here ]------------ [ 952.206714] kernel BUG at ../fs/btrfs/send.c:5653! [ 952.206719] Internal error: Oops - BUG: 0 [#1] SMP [ 952.209854] Modules linked in: st dm_mod nls_utf8 isofs fuse nf_log_ipv6 xt_pkttype xt_physdev br_netfilter nf_log_ipv4 nf_log_common xt_LOG xt_limit ebtable_filter ebtables af_packet bridge stp llc ip6t_REJECT xt_tcpudp nf_conntrack_ipv6 nf_defrag_ipv6 ip6table_raw ipt_REJECT iptable_raw xt_CT iptable_filter ip6table_mangle nf_conntrack_netbios_ns nf_conntrack_broadcast nf_conntrack_ipv4 nf_defrag_ipv4 ip_tables xt_conntrack nf_conntrack ip6table_filter ip6_tables x_tables xfs libcrc32c nls_iso8859_1 nls_cp437 vfat fat joydev aes_ce_blk ablk_helper cryptd snd_intel8x0 aes_ce_cipher snd_ac97_codec ac97_bus snd_pcm ghash_ce sha2_ce sha1_ce snd_timer snd virtio_net soundcore btrfs xor sr_mod cdrom hid_generic usbhid raid6_pq virtio_blk virtio_scsi bochs_drm drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops ttm virtio_mmio xhci_pci xhci_hcd usbcore usb_common virtio_pci virtio_ring virtio drm sg efivarfs [ 952.228333] Supported: Yes [ 952.228908] CPU: 0 PID: 12779 Comm: snapperd Not tainted 4.4.14-50-default #1 [ 952.230329] Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015 [ 952.231683] task: ffff800058e94100 ti: ffff8000d866c000 task.ti: ffff8000d866c000 [ 952.233279] PC is at changed_cb+0x9f4/0xa48 [btrfs] [ 952.234375] LR is at changed_cb+0x58/0xa48 [btrfs] [ 952.236552] pc : [<ffff7ffffc39de7c>] lr : [<ffff7ffffc39d4e0>] pstate: 80000145 [ 952.238049] sp : ffff8000d866fa20 [ 952.238732] x29: ffff8000d866fa20 x28: 0000000000000019 [ 952.239840] x27: 00000000000028d5 x26: 00000000000024a2 [ 952.241008] x25: 0000000000000002 x24: ffff8000e66e92f0 [ 952.242131] x23: ffff8000b8c76800 x22: ffff800092879140 [ 952.243238] x21: 0000000000000002 x20: ffff8000d866fb78 [ 952.244348] x19: ffff8000b8f8c200 x18: 0000000000002710 [ 952.245607] x17: 0000ffff90d42480 x16: ffff800000237dc0 [ 952.246719] x15: 0000ffff90de7510 x14: ab000c000a2faf08 [ 952.247835] x13: 0000000000577c2b x12: ab000c000b696665 [ 952.248981] x11: 2e65726f632f6966 x10: 652d34366d72612f [ 952.250101] x9 : 32627572672f746f x8 : ab000c00092f1671 [ 952.251352] x7 : 8000000000577c2b x6 : ffff800053eadf45 [ 952.252468] x5 : 0000000000000000 x4 : ffff80005e169494 [ 952.253582] x3 : 0000000000000004 x2 : ffff8000d866fb78 [ 952.254695] x1 : 000000000003e2a3 x0 : 000000000003e2a4 [ 952.255803] [ 952.256150] Process snapperd (pid: 12779, stack limit = 0xffff8000d866c020) [ 952.257516] Stack: (0xffff8000d866fa20 to 0xffff8000d8670000) [ 952.258654] fa20: ffff8000d866fae0 ffff7ffffc308fc0 ffff800092879140 ffff8000e66e92f0 [ 952.260219] fa40: 0000000000000035 ffff800055de6000 ffff8000b8c76800 ffff8000d866fb78 [ 952.261745] fa60: 0000000000000002 00000000000024a2 00000000000028d5 0000000000000019 [ 952.263269] fa80: ffff8000d866fae0 ffff7ffffc3090f0 ffff8000d866fae0 ffff7ffffc309128 [ 952.264797] faa0: ffff800092879140 ffff8000e66e92f0 0000000000000035 ffff800055de6000 [ 952.268261] fac0: ffff8000b8c76800 ffff8000d866fb78 0000000000000002 0000000000001000 [ 952.269822] fae0: ffff8000d866fbc0 ffff7ffffc39ecfc ffff8000b8f8c200 ffff8000b8f8c368 [ 952.271368] fb00: ffff8000b8f8c378 ffff800055de6000 0000000000000001 ffff8000ecb17500 [ 952.272893] fb20: ffff8000b8c76800 ffff800092879140 ffff800062b6d000 ffff80007a9e2470 [ 952.274420] fb40: ffff8000b8f8c208 0000000005784000 ffff8000580a8000 ffff8000b8f8c200 [ 952.276088] fb60: ffff7ffffc39d488 00000002b8f8c368 0000000000000000 000000000003e2a4 [ 952.280275] fb80: 000000000000006c ffff7ffffc39ec00 000000000003e2a4 000000000000006c [ 952.283219] fba0: ffff8000b8f8c300 0000000000000100 0000000000000001 ffff8000ecb17500 [ 952.286166] fbc0: ffff8000d866fcd0 ffff7ffffc3643c0 ffff8000f8842700 0000ffff8ffe9278 [ 952.289136] fbe0: 0000000040489426 ffff800055de6000 0000ffff8ffe9278 0000000040489426 [ 952.292083] fc00: 000000000000011d 000000000000001d ffff80007a9e4598 ffff80007a9e43e8 [ 952.294959] fc20: ffff8000b8c7693f 0000000000003b24 0000000000000019 ffff8000b8f8c218 [ 952.301161] fc40: 00000001d866fc70 ffff8000b8c76800 0000000000000128 ffffffffffffff84 [ 952.305749] fc60: ffff800058e941ff 0000000000003a58 ffff8000d866fcb0 ffff8000000f7390 [ 952.308875] fc80: 000000000000012a 0000000000010290 ffff8000d866fc00 000000000000007b [ 952.311915] fca0: 0000000000010290 ffff800046c1b100 74732d7366727462 000001006d616572 [ 952.314937] fcc0: ffff8000fffc4100 cb88537fdc8ba60e ffff8000d866fe10 ffff8000002499e8 [ 952.318008] fce0: 0000000040489426 ffff8000f8842700 0000ffff8ffe9278 ffff80007a9e4598 [ 952.321321] fd00: 0000ffff8ffe9278 0000000040489426 000000000000011d 000000000000001d [ 952.324280] fd20: ffff80000072c000 ffff8000d866c000 ffff8000d866fda0 ffff8000000e997c [ 952.327156] fd40: ffff8000fffc4180 00000000000031ed ffff8000fffc4180 ffff800046c1b7d4 [ 952.329895] fd60: 0000000000000140 0000ffff907ea170 000000000000011d 00000000000000dc [ 952.334641] fd80: ffff80000072c000 ffff8000d866c000 0000000000000000 0000000000000002 [ 952.338002] fda0: ffff8000d866fdd0 ffff8000000ebacc ffff800046c1b080 ffff800046c1b7d4 [ 952.340724] fdc0: ffff8000d866fdf0 ffff8000000db67c 0000000000000040 ffff800000e69198 [ 952.343415] fde0: 0000ffff8ffea790 00000000000031ed ffff8000d866fe20 ffff800000254000 [ 952.346101] fe00: 000000000000001d 0000000000000004 ffff8000d866fe90 ffff800000249d3c [ 952.348980] fe20: ffff8000f8842700 0000000000000000 ffff8000f8842701 0000000000000008 [ 952.351696] fe40: ffff8000d866fe70 0000000000000008 ffff8000d866fe90 ffff800000249cf8 [ 952.354387] fe60: ffff8000f8842700 0000ffff8ffe9170 ffff8000f8842701 0000000000000008 [ 952.357083] fe80: 0000ffff8ffe9278 ffff80008ff85500 0000ffff8ffe90c0 ffff800000085c84 [ 952.359800] fea0: 0000000000000000 0000ffff8ffe9170 ffffffffffffffff 0000ffff90d473bc [ 952.365351] fec0: 0000000000000000 0000000000000015 0000000000000008 0000000040489426 [ 952.369550] fee0: 0000ffff8ffe9278 0000ffff907ea790 0000ffff907ea170 0000ffff907ea790 [ 952.372416] ff00: 0000ffff907ea170 0000000000000000 000000000000001d 0000000000000004 [ 952.375223] ff20: 0000ffff90a32220 00000000003d0f00 0000ffff907ea0a0 0000ffff8ffe8f30 [ 952.378099] ff40: 0000ffff9100f554 0000ffff91147000 0000ffff91117bc0 0000ffff90d473b0 [ 952.381115] ff60: 0000ffff9100f620 0000ffff880069b0 0000ffff8ffe9170 0000ffff8ffe91a0 [ 952.384003] ff80: 0000ffff8ffe9160 0000ffff8ffe9140 0000ffff88006990 0000ffff8ffe9278 [ 952.386860] ffa0: 0000ffff88008a60 0000ffff8ffe9480 0000ffff88014ca0 0000ffff8ffe90c0 [ 952.389654] ffc0: 0000ffff910be8e8 0000ffff8ffe90c0 0000ffff90d473bc 0000000000000000 [ 952.410986] ffe0: 0000000000000008 000000000000001d 6e2079747265706f 72616d223d656d61 [ 952.415497] Call trace: [ 952.417403] [<ffff7ffffc39de7c>] changed_cb+0x9f4/0xa48 [btrfs] [ 952.420023] [<ffff7ffffc308fc0>] btrfs_compare_trees+0x500/0x6b0 [btrfs] [ 952.422759] [<ffff7ffffc39ecfc>] btrfs_ioctl_send+0xb4c/0xe10 [btrfs] [ 952.425601] [<ffff7ffffc3643c0>] btrfs_ioctl+0x374/0x29a4 [btrfs] [ 952.428031] [<ffff8000002499e8>] do_vfs_ioctl+0x33c/0x600 [ 952.430360] [<ffff800000249d3c>] SyS_ioctl+0x90/0xa4 [ 952.432552] [<ffff800000085c84>] el0_svc_naked+0x38/0x3c [ 952.434803] Code: 2a1503e0 17fffdac b9404282 17ffff28 (d4210000) [ 952.437457] ---[ end trace 9afd7090c466cf15 ]--- Signed-off-by: Filipe Manana <fdmanana@suse.com>
2016-10-11Merge branch 'for-linus-4.9' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs Pull btrfs updates from Chris Mason: "This is a big variety of fixes and cleanups. Liu Bo continues to fixup fuzzer related problems, and some of Josef's cleanups are prep for his bigger extent buffer changes (slated for v4.10)" * 'for-linus-4.9' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (39 commits) Revert "btrfs: let btrfs_delete_unused_bgs() to clean relocated bgs" Btrfs: remove unnecessary btrfs_mark_buffer_dirty in split_leaf Btrfs: don't BUG() during drop snapshot btrfs: fix btrfs_no_printk stub helper Btrfs: memset to avoid stale content in btree leaf btrfs: parent_start initialization cleanup btrfs: Remove already completed TODO comment btrfs: Do not reassign count in btrfs_run_delayed_refs btrfs: fix a possible umount deadlock Btrfs: fix memory leak in do_walk_down btrfs: btrfs_debug should consume fs_info when DEBUG is not defined btrfs: convert send's verbose_printk to btrfs_debug btrfs: convert pr_* to btrfs_* where possible btrfs: convert printk(KERN_* to use pr_* calls btrfs: unsplit printed strings btrfs: clean the old superblocks before freeing the device Btrfs: kill BUG_ON in run_delayed_tree_ref Btrfs: don't leak reloc root nodes on error btrfs: squash lines for simple wrapper functions Btrfs: improve check_node to avoid reading corrupted nodes ...
2016-09-27posix_acl: xattr representation cleanupsAndreas Gruenbacher
Remove the unnecessary typedefs and the zero-length a_entries array in struct posix_acl_xattr_header. Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-09-26btrfs: convert send's verbose_printk to btrfs_debugJeff Mahoney
This was basically an open-coded, less flexible dynamic printk. We can just use btrfs_debug instead. Signed-off-by: Jeff Mahoney <jeffm@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2016-09-26btrfs: unsplit printed stringsJeff Mahoney
CodingStyle chapter 2: "[...] never break user-visible strings such as printk messages, because that breaks the ability to grep for them." This patch unsplits user-visible strings. Signed-off-by: Jeff Mahoney <jeffm@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2016-09-26btrfs: squash lines for simple wrapper functionsMasahiro Yamada
Remove unneeded variables and assignments. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2016-09-01Btrfs: kill invalid ASSERT() in process_all_refs()Josef Bacik
Suppose you have the following tree in snap1 on a file system mounted with -o inode_cache so that inode numbers are recycled └── [ 258] a └── [ 257] b and then you remove b, rename a to c, and then re-create b in c so you have the following tree └── [ 258] c └── [ 257] b and then you try to do an incremental send you will hit ASSERT(pending_move == 0); in process_all_refs(). This is because we assume that any recycling of inodes will not have a pending change in our path, which isn't the case. This is the case for the DELETE side, since we want to remove the old file using the old path, but on the create side we could have a pending move and need to do the normal pending rename dance. So remove this ASSERT() and put a comment about why we ignore pending_move. Thanks, Signed-off-by: Josef Bacik <jbacik@fb.com> Signed-off-by: David Sterba <dsterba@suse.com>
2016-08-01Btrfs: send, don't bug on inconsistent snapshotsFilipe Manana
When doing an incremental send, if we find a new/modified/deleted extent, reference or xattr without having previously processed the corresponding inode item we end up exexuting a BUG_ON(). This is because whenever an extent, xattr or reference is added, modified or deleted, we always expect to have the corresponding inode item updated. However there are situations where this will not happen due to transient -ENOMEM or -ENOSPC errors when doing delayed inode updates. For example, when punching holes we can succeed in deleting and modifying (shrinking) extents but later fail to do the delayed inode update. So after such failure we close our transaction handle and right after a snapshot of the fs/subvol tree can be made and used later for a send operation. The same thing can happen during truncate, link, unlink, and xattr related operations. So instead of executing a BUG_ON, make send return an -EIO error and print an informative error message do dmesg/syslog. Signed-off-by: Filipe Manana <fdmanana@suse.com>
2016-08-01Btrfs: send, avoid incorrect leaf accesses when sending utimes operationsFilipe Manana
The caller of send_utimes() is supposed to be sure that the inode number it passes to this function does actually exists in the send snapshot. However due to logic/algorithm bugs (such as the one fixed by the patch titled "Btrfs: send, fix invalid leaf accesses due to incorrect utimes operations"), this might not be the case and when that happens it makes send_utimes() access use an unrelated leaf item as the target inode item or access beyond a leaf's boundaries (when the leaf is full and path->slots[0] matches the number of items in the leaf). So if the call to btrfs_search_slot() done by send_utimes() does not find the inode item, just make sure send_utimes() returns -ENOENT and does not silently accesses unrelated leaf items or does invalid leaf accesses, also allowing us to easialy and deterministically catch such algorithmic/logic bugs. Signed-off-by: Filipe Manana <fdmanana@suse.com>
2016-08-01Btrfs: send, fix invalid leaf accesses due to incorrect utimes operationsRobbie Ko
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: Filipe Manana <fdmanana@suse.com>
2016-08-01Btrfs: send, fix warning due to late freeing of orphan_dir_info structuresRobbie Ko
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 <robbieko@synology.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> [Modified changelog to be more detailed and easier to understand]
2016-08-01Btrfs: incremental send, fix premature rmdir operationsRobbie Ko
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: Robbie Ko <robbieko@synology.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> [Rewrote change log to be more detailed, clear and well formatted] Signed-off-by: Filipe Manana <fdmanana@suse.com>
2016-08-01Btrfs: incremental send, fix invalid paths for rename operationsFilipe Manana
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: Robbie Ko <robbieko@synology.com> Signed-off-by: Filipe Manana <fdmanana@suse.com>
2016-08-01Btrfs: send, add missing error check for calls to path_loop()Filipe Manana
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: Filipe Manana <fdmanana@suse.com>
2016-08-01Btrfs: send, fix failure to move directories with the same name aroundRobbie Ko
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: Robbie Ko <robbieko@synology.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> [Rewrote change log to be more detailed and organized, and improved comments] Signed-off-by: Filipe Manana <fdmanana@suse.com>
2016-05-25Merge branch 'cleanups-4.7' into for-chris-4.7-20160525David Sterba
2016-05-25btrfs: fix string and comment grammatical issues and typosNicholas D Steeves
Signed-off-by: Nicholas D Steeves <nsteeves@gmail.com> Signed-off-by: David Sterba <dsterba@suse.com>
2016-05-06btrfs: send: use vmalloc only as fallback for clone_sources_tmpDavid Sterba
Signed-off-by: David Sterba <dsterba@suse.com>
2016-05-06btrfs: send: use vmalloc only as fallback for clone_rootsDavid Sterba
Signed-off-by: David Sterba <dsterba@suse.com>
2016-05-06btrfs: send: use temporary variable to store allocation sizeDavid Sterba
We're going to use the argument multiple times later. Signed-off-by: David Sterba <dsterba@suse.com>
2016-05-06btrfs: send: use vmalloc only as fallback for read_bufDavid Sterba
Signed-off-by: David Sterba <dsterba@suse.com>