Commit graph

9948 commits

Author SHA1 Message Date
Linus Torvalds
a4f7fae101 Merge branch 'miklos.fileattr' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull fileattr conversion updates from Miklos Szeredi via Al Viro:
 "This splits the handling of FS_IOC_[GS]ETFLAGS from ->ioctl() into a
  separate method.

  The interface is reasonably uniform across the filesystems that
  support it and gives nice boilerplate removal"

* 'miklos.fileattr' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (23 commits)
  ovl: remove unneeded ioctls
  fuse: convert to fileattr
  fuse: add internal open/release helpers
  fuse: unsigned open flags
  fuse: move ioctl to separate source file
  vfs: remove unused ioctl helpers
  ubifs: convert to fileattr
  reiserfs: convert to fileattr
  ocfs2: convert to fileattr
  nilfs2: convert to fileattr
  jfs: convert to fileattr
  hfsplus: convert to fileattr
  efivars: convert to fileattr
  xfs: convert to fileattr
  orangefs: convert to fileattr
  gfs2: convert to fileattr
  f2fs: convert to fileattr
  ext4: convert to fileattr
  ext2: convert to fileattr
  btrfs: convert to fileattr
  ...
2021-04-27 11:18:24 -07:00
Linus Torvalds
57fa2369ab CFI on arm64 series for v5.13-rc1
- Clean up list_sort prototypes (Sami Tolvanen)
 
 - Introduce CONFIG_CFI_CLANG for arm64 (Sami Tolvanen)
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Merge tag 'cfi-v5.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux

Pull CFI on arm64 support from Kees Cook:
 "This builds on last cycle's LTO work, and allows the arm64 kernels to
  be built with Clang's Control Flow Integrity feature. This feature has
  happily lived in Android kernels for almost 3 years[1], so I'm excited
  to have it ready for upstream.

  The wide diffstat is mainly due to the treewide fixing of mismatched
  list_sort prototypes. Other things in core kernel are to address
  various CFI corner cases. The largest code portion is the CFI runtime
  implementation itself (which will be shared by all architectures
  implementing support for CFI). The arm64 pieces are Acked by arm64
  maintainers rather than coming through the arm64 tree since carrying
  this tree over there was going to be awkward.

  CFI support for x86 is still under development, but is pretty close.
  There are a handful of corner cases on x86 that need some improvements
  to Clang and objtool, but otherwise works well.

  Summary:

   - Clean up list_sort prototypes (Sami Tolvanen)

   - Introduce CONFIG_CFI_CLANG for arm64 (Sami Tolvanen)"

* tag 'cfi-v5.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  arm64: allow CONFIG_CFI_CLANG to be selected
  KVM: arm64: Disable CFI for nVHE
  arm64: ftrace: use function_nocfi for ftrace_call
  arm64: add __nocfi to __apply_alternatives
  arm64: add __nocfi to functions that jump to a physical address
  arm64: use function_nocfi with __pa_symbol
  arm64: implement function_nocfi
  psci: use function_nocfi for cpu_resume
  lkdtm: use function_nocfi
  treewide: Change list_sort to use const pointers
  bpf: disable CFI in dispatcher functions
  kallsyms: strip ThinLTO hashes from static functions
  kthread: use WARN_ON_FUNCTION_MISMATCH
  workqueue: use WARN_ON_FUNCTION_MISMATCH
  module: ensure __cfi_check alignment
  mm: add generic function_nocfi macro
  cfi: add __cficanonical
  add support for Clang CFI
2021-04-27 10:16:46 -07:00
Johannes Thumshirn
18bb8bbf13 btrfs: zoned: automatically reclaim zones
When a file gets deleted on a zoned file system, the space freed is not
returned back into the block group's free space, but is migrated to
zone_unusable.

As this zone_unusable space is behind the current write pointer it is not
possible to use it for new allocations. In the current implementation a
zone is reset once all of the block group's space is accounted as zone
unusable.

This behaviour can lead to premature ENOSPC errors on a busy file system.

Instead of only reclaiming the zone once it is completely unusable,
kick off a reclaim job once the amount of unusable bytes exceeds a user
configurable threshold between 51% and 100%. It can be set per mounted
filesystem via the sysfs tunable bg_reclaim_threshold which is set to 75%
by default.

Similar to reclaiming unused block groups, these dirty block groups are
added to a to_reclaim list and then on a transaction commit, the reclaim
process is triggered but after we deleted unused block groups, which will
free space for the relocation process.

Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-20 20:46:31 +02:00
Johannes Thumshirn
f33720657d btrfs: rename delete_unused_bgs_mutex to reclaim_bgs_lock
As a preparation for extending the block group deletion use case, rename
the unused_bgs_mutex to reclaim_bgs_lock.

Reviewed-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-20 20:30:18 +02:00
Johannes Thumshirn
01e86008aa btrfs: zoned: reset zones of relocated block groups
When relocating a block group the freed up space is not discarded in one
big block, but each extent is discarded on its own with -odisard=sync.

For a zoned filesystem we need to discard the whole block group at once,
so btrfs_discard_extent() will translate the discard into a
REQ_OP_ZONE_RESET operation, which then resets the device's zone.
Failure to reset the zone is not fatal error.

Discussion about the approach and regarding transaction blocking:
https://lore.kernel.org/linux-btrfs/CAL3q7H4SjS_d5rBepfTMhU8Th3bJzdmyYd0g4Z60yUgC_rC_ZA@mail.gmail.com/

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-20 20:25:16 +02:00
Qu Wenruo
e9306ad4ef btrfs: more graceful errors/warnings on 32bit systems when reaching limits
Btrfs uses internally mapped u64 address space for all its metadata.
Due to the page cache limit on 32bit systems, btrfs can't access
metadata at or beyond (ULONG_MAX + 1) << PAGE_SHIFT. See
how MAX_LFS_FILESIZE and page::index are defined.  This is 16T for 4K
page size while 256T for 64K page size.

Users can have a filesystem which doesn't have metadata beyond the
boundary at mount time, but later balance can cause it to create
metadata beyond the boundary.

And modification to MM layer is unrealistic just for such minor use
case. We can't do more than to prevent mounting such filesystem or warn
early when the numbers are still within the limits.

To address such problem, this patch will introduce the following checks:

- Mount time rejection
  This will reject any fs which has metadata chunk at or beyond the
  boundary.

- Mount time early warning
  If there is any metadata chunk beyond 5/8th of the boundary, we do an
  early warning and hope the end user will see it.

- Runtime extent buffer rejection
  If we're going to allocate an extent buffer at or beyond the boundary,
  reject such request with EOVERFLOW.
  This is definitely going to cause problems like transaction abort, but
  we have no better ways.

- Runtime extent buffer early warning
  If an extent buffer beyond 5/8th of the max file size is allocated, do
  an early warning.

Above error/warning message will only be printed once for each fs to
reduce dmesg flood.

If the mount is rejected, the filesystem will be mountable only on a
64bit host.

Link: https://lore.kernel.org/linux-btrfs/1783f16d-7a28-80e6-4c32-fdf19b705ed0@gmx.com/
Reported-by: Erik Jensen <erikjensen@rkjnsn.net>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-20 19:56:50 +02:00
Filipe Manana
0dc16ef4f6 btrfs: zoned: fix unpaired block group unfreeze during device replace
When doing a device replace on a zoned filesystem, if we find a block
group with ->to_copy == 0, we jump to the label 'done', which will result
in later calling btrfs_unfreeze_block_group(), even though at this point
we never called btrfs_freeze_block_group().

Since at this point we have neither turned the block group to RO mode nor
made any progress, we don't need to jump to the label 'done'. So fix this
by jumping instead to the label 'skip' and dropping our reference on the
block group before the jump.

Fixes: 78ce9fc269 ("btrfs: zoned: mark block groups to copy for device-replace")
CC: stable@vger.kernel.org # 5.12
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-20 19:32:43 +02:00
Filipe Manana
f9690f426b btrfs: fix race when picking most recent mod log operation for an old root
Commit dbcc7d57bf ("btrfs: fix race when cloning extent buffer during
rewind of an old root"), fixed a race when we need to rewind the extent
buffer of an old root. It was caused by picking a new mod log operation
for the extent buffer while getting a cloned extent buffer with an outdated
number of items (off by -1), because we cloned the extent buffer without
locking it first.

However there is still another similar race, but in the opposite direction.
The cloned extent buffer has a number of items that does not match the
number of tree mod log operations that are going to be replayed. This is
because right after we got the last (most recent) tree mod log operation to
replay and before locking and cloning the extent buffer, another task adds
a new pointer to the extent buffer, which results in adding a new tree mod
log operation and incrementing the number of items in the extent buffer.
So after cloning we have mismatch between the number of items in the extent
buffer and the number of mod log operations we are going to apply to it.
This results in hitting a BUG_ON() that produces the following stack trace:

   ------------[ cut here ]------------
   kernel BUG at fs/btrfs/tree-mod-log.c:675!
   invalid opcode: 0000 [#1] SMP KASAN PTI
   CPU: 3 PID: 4811 Comm: crawl_1215 Tainted: G        W         5.12.0-7d1efdf501f8-misc-next+ #99
   Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014
   RIP: 0010:tree_mod_log_rewind+0x3b1/0x3c0
   Code: 05 48 8d 74 10 (...)
   RSP: 0018:ffffc90001027090 EFLAGS: 00010293
   RAX: 0000000000000000 RBX: ffff8880a8514600 RCX: ffffffffaa9e59b6
   RDX: 0000000000000007 RSI: dffffc0000000000 RDI: ffff8880a851462c
   RBP: ffffc900010270e0 R08: 00000000000000c0 R09: ffffed1004333417
   R10: ffff88802199a0b7 R11: ffffed1004333416 R12: 000000000000000e
   R13: ffff888135af8748 R14: ffff88818766ff00 R15: ffff8880a851462c
   FS:  00007f29acf62700(0000) GS:ffff8881f2200000(0000) knlGS:0000000000000000
   CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
   CR2: 00007f0e6013f718 CR3: 000000010d42e003 CR4: 0000000000170ee0
   Call Trace:
    btrfs_get_old_root+0x16a/0x5c0
    ? lock_downgrade+0x400/0x400
    btrfs_search_old_slot+0x192/0x520
    ? btrfs_search_slot+0x1090/0x1090
    ? free_extent_buffer.part.61+0xd7/0x140
    ? free_extent_buffer+0x13/0x20
    resolve_indirect_refs+0x3e9/0xfc0
    ? lock_downgrade+0x400/0x400
    ? __kasan_check_read+0x11/0x20
    ? add_prelim_ref.part.11+0x150/0x150
    ? lock_downgrade+0x400/0x400
    ? __kasan_check_read+0x11/0x20
    ? lock_acquired+0xbb/0x620
    ? __kasan_check_write+0x14/0x20
    ? do_raw_spin_unlock+0xa8/0x140
    ? rb_insert_color+0x340/0x360
    ? prelim_ref_insert+0x12d/0x430
    find_parent_nodes+0x5c3/0x1830
    ? stack_trace_save+0x87/0xb0
    ? resolve_indirect_refs+0xfc0/0xfc0
    ? fs_reclaim_acquire+0x67/0xf0
    ? __kasan_check_read+0x11/0x20
    ? lockdep_hardirqs_on_prepare+0x210/0x210
    ? fs_reclaim_acquire+0x67/0xf0
    ? __kasan_check_read+0x11/0x20
    ? ___might_sleep+0x10f/0x1e0
    ? __kasan_kmalloc+0x9d/0xd0
    ? trace_hardirqs_on+0x55/0x120
    btrfs_find_all_roots_safe+0x142/0x1e0
    ? find_parent_nodes+0x1830/0x1830
    ? trace_hardirqs_on+0x55/0x120
    ? ulist_free+0x1f/0x30
    ? btrfs_inode_flags_to_xflags+0x50/0x50
    iterate_extent_inodes+0x20e/0x580
    ? tree_backref_for_extent+0x230/0x230
    ? release_extent_buffer+0x225/0x280
    ? read_extent_buffer+0xdd/0x110
    ? lock_downgrade+0x400/0x400
    ? __kasan_check_read+0x11/0x20
    ? lock_acquired+0xbb/0x620
    ? __kasan_check_write+0x14/0x20
    ? do_raw_spin_unlock+0xa8/0x140
    ? _raw_spin_unlock+0x22/0x30
    ? release_extent_buffer+0x225/0x280
    iterate_inodes_from_logical+0x129/0x170
    ? iterate_inodes_from_logical+0x129/0x170
    ? btrfs_inode_flags_to_xflags+0x50/0x50
    ? iterate_extent_inodes+0x580/0x580
    ? __vmalloc_node+0x92/0xb0
    ? init_data_container+0x34/0xb0
    ? init_data_container+0x34/0xb0
    ? kvmalloc_node+0x60/0x80
    btrfs_ioctl_logical_to_ino+0x158/0x230
    btrfs_ioctl+0x2038/0x4360
    ? __kasan_check_write+0x14/0x20
    ? mmput+0x3b/0x220
    ? btrfs_ioctl_get_supported_features+0x30/0x30
    ? __kasan_check_read+0x11/0x20
    ? __kasan_check_read+0x11/0x20
    ? lock_release+0xc8/0x650
    ? __might_fault+0x64/0xd0
    ? __kasan_check_read+0x11/0x20
    ? lock_downgrade+0x400/0x400
    ? lockdep_hardirqs_on_prepare+0x210/0x210
    ? lockdep_hardirqs_on_prepare+0x13/0x210
    ? _raw_spin_unlock_irqrestore+0x51/0x63
    ? __kasan_check_read+0x11/0x20
    ? do_vfs_ioctl+0xfc/0x9d0
    ? ioctl_file_clone+0xe0/0xe0
    ? lock_downgrade+0x400/0x400
    ? lockdep_hardirqs_on_prepare+0x210/0x210
    ? __kasan_check_read+0x11/0x20
    ? lock_release+0xc8/0x650
    ? __task_pid_nr_ns+0xd3/0x250
    ? __kasan_check_read+0x11/0x20
    ? __fget_files+0x160/0x230
    ? __fget_light+0xf2/0x110
    __x64_sys_ioctl+0xc3/0x100
    do_syscall_64+0x37/0x80
    entry_SYSCALL_64_after_hwframe+0x44/0xae
   RIP: 0033:0x7f29ae85b427
   Code: 00 00 90 48 8b (...)
   RSP: 002b:00007f29acf5fcf8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
   RAX: ffffffffffffffda RBX: 00007f29acf5ff40 RCX: 00007f29ae85b427
   RDX: 00007f29acf5ff48 RSI: 00000000c038943b RDI: 0000000000000003
   RBP: 0000000001000000 R08: 0000000000000000 R09: 00007f29acf60120
   R10: 00005640d5fc7b00 R11: 0000000000000246 R12: 0000000000000003
   R13: 00007f29acf5ff48 R14: 00007f29acf5ff40 R15: 00007f29acf5fef8
   Modules linked in:
   ---[ end trace 85e5fce078dfbe04 ]---

  (gdb) l *(tree_mod_log_rewind+0x3b1)
  0xffffffff819e5b21 is in tree_mod_log_rewind (fs/btrfs/tree-mod-log.c:675).
  670                      * the modification. As we're going backwards, we do the
  671                      * opposite of each operation here.
  672                      */
  673                     switch (tm->op) {
  674                     case BTRFS_MOD_LOG_KEY_REMOVE_WHILE_FREEING:
  675                             BUG_ON(tm->slot < n);
  676                             fallthrough;
  677                     case BTRFS_MOD_LOG_KEY_REMOVE_WHILE_MOVING:
  678                     case BTRFS_MOD_LOG_KEY_REMOVE:
  679                             btrfs_set_node_key(eb, &tm->key, tm->slot);
  (gdb) quit

The following steps explain in more detail how it happens:

1) We have one tree mod log user (through fiemap or the logical ino ioctl),
   with a sequence number of 1, so we have fs_info->tree_mod_seq == 1.
   This is task A;

2) Another task is at ctree.c:balance_level() and we have eb X currently as
   the root of the tree, and we promote its single child, eb Y, as the new
   root.

   Then, at ctree.c:balance_level(), we call:

      ret = btrfs_tree_mod_log_insert_root(root->node, child, true);

3) At btrfs_tree_mod_log_insert_root() we create a tree mod log operation
   of type BTRFS_MOD_LOG_KEY_REMOVE_WHILE_FREEING, with a ->logical field
   pointing to ebX->start. We only have one item in eb X, so we create
   only one tree mod log operation, and store in the "tm_list" array;

4) Then, still at btrfs_tree_mod_log_insert_root(), we create a tree mod
   log element of operation type BTRFS_MOD_LOG_ROOT_REPLACE, ->logical set
   to ebY->start, ->old_root.logical set to ebX->start, ->old_root.level
   set to the level of eb X and ->generation set to the generation of eb X;

5) Then btrfs_tree_mod_log_insert_root() calls tree_mod_log_free_eb() with
   "tm_list" as argument. After that, tree_mod_log_free_eb() calls
   tree_mod_log_insert(). This inserts the mod log operation of type
   BTRFS_MOD_LOG_KEY_REMOVE_WHILE_FREEING from step 3 into the rbtree
   with a sequence number of 2 (and fs_info->tree_mod_seq set to 2);

6) Then, after inserting the "tm_list" single element into the tree mod
   log rbtree, the BTRFS_MOD_LOG_ROOT_REPLACE element is inserted, which
   gets the sequence number 3 (and fs_info->tree_mod_seq set to 3);

7) Back to ctree.c:balance_level(), we free eb X by calling
   btrfs_free_tree_block() on it. Because eb X was created in the current
   transaction, has no other references and writeback did not happen for
   it, we add it back to the free space cache/tree;

8) Later some other task B allocates the metadata extent from eb X, since
   it is marked as free space in the space cache/tree, and uses it as a
   node for some other btree;

9) The tree mod log user task calls btrfs_search_old_slot(), which calls
   btrfs_get_old_root(), and finally that calls tree_mod_log_oldest_root()
   with time_seq == 1 and eb_root == eb Y;

10) The first iteration of the while loop finds the tree mod log element
    with sequence number 3, for the logical address of eb Y and of type
    BTRFS_MOD_LOG_ROOT_REPLACE;

11) Because the operation type is BTRFS_MOD_LOG_ROOT_REPLACE, we don't
    break out of the loop, and set root_logical to point to
    tm->old_root.logical, which corresponds to the logical address of
    eb X;

12) On the next iteration of the while loop, the call to
    tree_mod_log_search_oldest() returns the smallest tree mod log element
    for the logical address of eb X, which has a sequence number of 2, an
    operation type of BTRFS_MOD_LOG_KEY_REMOVE_WHILE_FREEING and
    corresponds to the old slot 0 of eb X (eb X had only 1 item in it
    before being freed at step 7);

13) We then break out of the while loop and return the tree mod log
    operation of type BTRFS_MOD_LOG_ROOT_REPLACE (eb Y), and not the one
    for slot 0 of eb X, to btrfs_get_old_root();

14) At btrfs_get_old_root(), we process the BTRFS_MOD_LOG_ROOT_REPLACE
    operation and set "logical" to the logical address of eb X, which was
    the old root. We then call tree_mod_log_search() passing it the logical
    address of eb X and time_seq == 1;

15) But before calling tree_mod_log_search(), task B locks eb X, adds a
    key to eb X, which results in adding a tree mod log operation of type
    BTRFS_MOD_LOG_KEY_ADD, with a sequence number of 4, to the tree mod
    log, and increments the number of items in eb X from 0 to 1.
    Now fs_info->tree_mod_seq has a value of 4;

16) Task A then calls tree_mod_log_search(), which returns the most recent
    tree mod log operation for eb X, which is the one just added by task B
    at the previous step, with a sequence number of 4, a type of
    BTRFS_MOD_LOG_KEY_ADD and for slot 0;

17) Before task A locks and clones eb X, task A adds another key to eb X,
    which results in adding a new BTRFS_MOD_LOG_KEY_ADD mod log operation,
    with a sequence number of 5, for slot 1 of eb X, increments the
    number of items in eb X from 1 to 2, and unlocks eb X.
    Now fs_info->tree_mod_seq has a value of 5;

18) Task A then locks eb X and clones it. The clone has a value of 2 for
    the number of items and the pointer "tm" points to the tree mod log
    operation with sequence number 4, not the most recent one with a
    sequence number of 5, so there is mismatch between the number of
    mod log operations that are going to be applied to the cloned version
    of eb X and the number of items in the clone;

19) Task A then calls tree_mod_log_rewind() with the clone of eb X, the
    tree mod log operation with sequence number 4 and a type of
    BTRFS_MOD_LOG_KEY_ADD, and time_seq == 1;

20) At tree_mod_log_rewind(), we set the local variable "n" with a value
    of 2, which is the number of items in the clone of eb X.

    Then in the first iteration of the while loop, we process the mod log
    operation with sequence number 4, which is targeted at slot 0 and has
    a type of BTRFS_MOD_LOG_KEY_ADD. This results in decrementing "n" from
    2 to 1.

    Then we pick the next tree mod log operation for eb X, which is the
    tree mod log operation with a sequence number of 2, a type of
    BTRFS_MOD_LOG_KEY_REMOVE_WHILE_FREEING and for slot 0, it is the one
    added in step 5 to the tree mod log tree.

    We go back to the top of the loop to process this mod log operation,
    and because its slot is 0 and "n" has a value of 1, we hit the BUG_ON:

        (...)
        switch (tm->op) {
        case BTRFS_MOD_LOG_KEY_REMOVE_WHILE_FREEING:
                BUG_ON(tm->slot < n);
                fallthrough;
	(...)

Fix this by checking for a more recent tree mod log operation after locking
and cloning the extent buffer of the old root node, and use it as the first
operation to apply to the cloned extent buffer when rewinding it.

Stable backport notes: due to moved code and renames, in =< 5.11 the
change should be applied to ctree.c:get_old_root.

Reported-by: Zygo Blaxell <ce3g8jdj@umail.furryterror.org>
Link: https://lore.kernel.org/linux-btrfs/20210404040732.GZ32440@hungrycats.org/
Fixes: 834328a849 ("Btrfs: tree mod log's old roots could still be part of the tree")
CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-20 19:27:17 +02:00
Filipe Manana
67addf2900 btrfs: fix metadata extent leak after failure to create subvolume
When creating a subvolume we allocate an extent buffer for its root node
after starting a transaction. We setup a root item for the subvolume that
points to that extent buffer and then attempt to insert the root item into
the root tree - however if that fails, due to ENOMEM for example, we do
not free the extent buffer previously allocated and we do not abort the
transaction (as at that point we did nothing that can not be undone).

This means that we effectively do not return the metadata extent back to
the free space cache/tree and we leave a delayed reference for it which
causes a metadata extent item to be added to the extent tree, in the next
transaction commit, without having backreferences. When this happens
'btrfs check' reports the following:

  $ btrfs check /dev/sdi
  Opening filesystem to check...
  Checking filesystem on /dev/sdi
  UUID: dce2cb9d-025f-4b05-a4bf-cee0ad3785eb
  [1/7] checking root items
  [2/7] checking extents
  ref mismatch on [30425088 16384] extent item 1, found 0
  backref 30425088 root 256 not referenced back 0x564a91c23d70
  incorrect global backref count on 30425088 found 1 wanted 0
  backpointer mismatch on [30425088 16384]
  owner ref check failed [30425088 16384]
  ERROR: errors found in extent allocation tree or chunk allocation
  [3/7] checking free space cache
  [4/7] checking fs roots
  [5/7] checking only csums items (without verifying data)
  [6/7] checking root refs
  [7/7] checking quota groups skipped (not enabled on this FS)
  found 212992 bytes used, error(s) found
  total csum bytes: 0
  total tree bytes: 131072
  total fs tree bytes: 32768
  total extent tree bytes: 16384
  btree space waste bytes: 124669
  file data blocks allocated: 65536
   referenced 65536

So fix this by freeing the metadata extent if btrfs_insert_root() returns
an error.

CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-20 19:16:01 +02:00
Qu Wenruo
1d8ba9e7e7 btrfs: handle remount to no compress during compression
[BUG]
When running btrfs/071 with inode_need_compress() removed from
compress_file_range(), we got the following crash:

  BUG: kernel NULL pointer dereference, address: 0000000000000018
  #PF: supervisor read access in kernel mode
  #PF: error_code(0x0000) - not-present page
  Workqueue: btrfs-delalloc btrfs_work_helper [btrfs]
  RIP: 0010:compress_file_range+0x476/0x7b0 [btrfs]
  Call Trace:
   ? submit_compressed_extents+0x450/0x450 [btrfs]
   async_cow_start+0x16/0x40 [btrfs]
   btrfs_work_helper+0xf2/0x3e0 [btrfs]
   process_one_work+0x278/0x5e0
   worker_thread+0x55/0x400
   ? process_one_work+0x5e0/0x5e0
   kthread+0x168/0x190
   ? kthread_create_worker_on_cpu+0x70/0x70
   ret_from_fork+0x22/0x30
  ---[ end trace 65faf4eae941fa7d ]---

This is already after the patch "btrfs: inode: fix NULL pointer
dereference if inode doesn't need compression."

[CAUSE]
@pages is firstly created by kcalloc() in compress_file_extent():
                pages = kcalloc(nr_pages, sizeof(struct page *), GFP_NOFS);

Then passed to btrfs_compress_pages() to be utilized there:

                ret = btrfs_compress_pages(...
                                           pages,
                                           &nr_pages,
                                           ...);

btrfs_compress_pages() will initialize each page as output, in
zlib_compress_pages() we have:

                        pages[nr_pages] = out_page;
                        nr_pages++;

Normally this is completely fine, but there is a special case which
is in btrfs_compress_pages() itself:

        switch (type) {
        default:
                return -E2BIG;
        }

In this case, we didn't modify @pages nor @out_pages, leaving them
untouched, then when we cleanup pages, the we can hit NULL pointer
dereference again:

        if (pages) {
                for (i = 0; i < nr_pages; i++) {
                        WARN_ON(pages[i]->mapping);
                        put_page(pages[i]);
                }
        ...
        }

Since pages[i] are all initialized to zero, and btrfs_compress_pages()
doesn't change them at all, accessing pages[i]->mapping would lead to
NULL pointer dereference.

This is not possible for current kernel, as we check
inode_need_compress() before doing pages allocation.
But if we're going to remove that inode_need_compress() in
compress_file_extent(), then it's going to be a problem.

[FIX]
When btrfs_compress_pages() hits its default case, modify @out_pages to
0 to prevent such problem from happening.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=212331
CC: stable@vger.kernel.org # 5.10+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19 21:32:45 +02:00
Johannes Thumshirn
1d68128c10 btrfs: zoned: fail mount if the device does not support zone append
For zoned btrfs, zone append is mandatory to write to a sequential write
only zone, otherwise parallel writes to the same zone could result in
unaligned write errors.

If a zoned block device does not support zone append (e.g. a dm-crypt
zoned device using a non-NULL IV cypher), fail to mount.

CC: stable@vger.kernel.org # 5.12
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19 17:25:23 +02:00
Filipe Manana
061dde8245 btrfs: fix race between transaction aborts and fsyncs leading to use-after-free
There is a race between a task aborting a transaction during a commit,
a task doing an fsync and the transaction kthread, which leads to an
use-after-free of the log root tree. When this happens, it results in a
stack trace like the following:

  BTRFS info (device dm-0): forced readonly
  BTRFS warning (device dm-0): Skipping commit of aborted transaction.
  BTRFS: error (device dm-0) in cleanup_transaction:1958: errno=-5 IO failure
  BTRFS warning (device dm-0): lost page write due to IO error on /dev/mapper/error-test (-5)
  BTRFS warning (device dm-0): Skipping commit of aborted transaction.
  BTRFS warning (device dm-0): direct IO failed ino 261 rw 0,0 sector 0xa4e8 len 4096 err no 10
  BTRFS error (device dm-0): error writing primary super block to device 1
  BTRFS warning (device dm-0): direct IO failed ino 261 rw 0,0 sector 0x12e000 len 4096 err no 10
  BTRFS warning (device dm-0): direct IO failed ino 261 rw 0,0 sector 0x12e008 len 4096 err no 10
  BTRFS warning (device dm-0): direct IO failed ino 261 rw 0,0 sector 0x12e010 len 4096 err no 10
  BTRFS: error (device dm-0) in write_all_supers:4110: errno=-5 IO failure (1 errors while writing supers)
  BTRFS: error (device dm-0) in btrfs_sync_log:3308: errno=-5 IO failure
  general protection fault, probably for non-canonical address 0x6b6b6b6b6b6b6b68: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC PTI
  CPU: 2 PID: 2458471 Comm: fsstress Not tainted 5.12.0-rc5-btrfs-next-84 #1
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
  RIP: 0010:__mutex_lock+0x139/0xa40
  Code: c0 74 19 (...)
  RSP: 0018:ffff9f18830d7b00 EFLAGS: 00010202
  RAX: 6b6b6b6b6b6b6b68 RBX: 0000000000000001 RCX: 0000000000000002
  RDX: ffffffffb9c54d13 RSI: 0000000000000000 RDI: 0000000000000000
  RBP: ffff9f18830d7bc0 R08: 0000000000000000 R09: 0000000000000000
  R10: ffff9f18830d7be0 R11: 0000000000000001 R12: ffff8c6cd199c040
  R13: ffff8c6c95821358 R14: 00000000fffffffb R15: ffff8c6cbcf01358
  FS:  00007fa9140c2b80(0000) GS:ffff8c6fac600000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 00007fa913d52000 CR3: 000000013d2b4003 CR4: 0000000000370ee0
  DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  Call Trace:
   ? __btrfs_handle_fs_error+0xde/0x146 [btrfs]
   ? btrfs_sync_log+0x7c1/0xf20 [btrfs]
   ? btrfs_sync_log+0x7c1/0xf20 [btrfs]
   btrfs_sync_log+0x7c1/0xf20 [btrfs]
   btrfs_sync_file+0x40c/0x580 [btrfs]
   do_fsync+0x38/0x70
   __x64_sys_fsync+0x10/0x20
   do_syscall_64+0x33/0x80
   entry_SYSCALL_64_after_hwframe+0x44/0xae
  RIP: 0033:0x7fa9142a55c3
  Code: 8b 15 09 (...)
  RSP: 002b:00007fff26278d48 EFLAGS: 00000246 ORIG_RAX: 000000000000004a
  RAX: ffffffffffffffda RBX: 0000563c83cb4560 RCX: 00007fa9142a55c3
  RDX: 00007fff26278cb0 RSI: 00007fff26278cb0 RDI: 0000000000000005
  RBP: 0000000000000005 R08: 0000000000000001 R09: 00007fff26278d5c
  R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000340
  R13: 00007fff26278de0 R14: 00007fff26278d96 R15: 0000563c83ca57c0
  Modules linked in: btrfs dm_zero dm_snapshot dm_thin_pool (...)
  ---[ end trace ee2f1b19327d791d ]---

The steps that lead to this crash are the following:

1) We are at transaction N;

2) We have two tasks with a transaction handle attached to transaction N.
   Task A and Task B. Task B is doing an fsync;

3) Task B is at btrfs_sync_log(), and has saved fs_info->log_root_tree
   into a local variable named 'log_root_tree' at the top of
   btrfs_sync_log(). Task B is about to call write_all_supers(), but
   before that...

4) Task A calls btrfs_commit_transaction(), and after it sets the
   transaction state to TRANS_STATE_COMMIT_START, an error happens before
   it waits for the transaction's 'num_writers' counter to reach a value
   of 1 (no one else attached to the transaction), so it jumps to the
   label "cleanup_transaction";

5) Task A then calls cleanup_transaction(), where it aborts the
   transaction, setting BTRFS_FS_STATE_TRANS_ABORTED on fs_info->fs_state,
   setting the ->aborted field of the transaction and the handle to an
   errno value and also setting BTRFS_FS_STATE_ERROR on fs_info->fs_state.

   After that, at cleanup_transaction(), it deletes the transaction from
   the list of transactions (fs_info->trans_list), sets the transaction
   to the state TRANS_STATE_COMMIT_DOING and then waits for the number
   of writers to go down to 1, as it's currently 2 (1 for task A and 1
   for task B);

6) The transaction kthread is running and sees that BTRFS_FS_STATE_ERROR
   is set in fs_info->fs_state, so it calls btrfs_cleanup_transaction().

   There it sees the list fs_info->trans_list is empty, and then proceeds
   into calling btrfs_drop_all_logs(), which frees the log root tree with
   a call to btrfs_free_log_root_tree();

7) Task B calls write_all_supers() and, shortly after, under the label
   'out_wake_log_root', it deferences the pointer stored in
   'log_root_tree', which was already freed in the previous step by the
   transaction kthread. This results in a use-after-free leading to a
   crash.

Fix this by deleting the transaction from the list of transactions at
cleanup_transaction() only after setting the transaction state to
TRANS_STATE_COMMIT_DOING and waiting for all existing tasks that are
attached to the transaction to release their transaction handles.
This makes the transaction kthread wait for all the tasks attached to
the transaction to be done with the transaction before dropping the
log roots and doing other cleanups.

Fixes: ef67963dac ("btrfs: drop logs when we've aborted a transaction")
CC: stable@vger.kernel.org # 5.10+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19 17:25:22 +02:00
Qu Wenruo
c4aec299fa btrfs: introduce submit_eb_subpage() to submit a subpage metadata page
The new function, submit_eb_subpage(), will submit all the dirty extent
buffers in the page.

The major difference between submit_eb_page() and submit_eb_subpage()
is:
- How to grab extent buffer
  Now we use find_extent_buffer_nospinlock() other than using
  page::private.

All other different handling is already done in functions like
lock_extent_buffer_for_io() and write_one_eb().

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19 17:25:22 +02:00
Qu Wenruo
f3156df944 btrfs: make lock_extent_buffer_for_io() to be subpage compatible
For subpage metadata, we don't use page locking at all.  So just skip
the page locking part for subpage.  The rest of the function can be
reused.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19 17:25:22 +02:00
Qu Wenruo
35b6ddfa96 btrfs: introduce write_one_subpage_eb() function
The new function, write_one_subpage_eb(), as a subroutine for subpage
metadata write, will handle the extent buffer bio submission.

The major differences between the new write_one_subpage_eb() and
write_one_eb() is:

- No page locking
  When entering write_one_subpage_eb() the page is no longer locked.
  We only lock the page for its status update, and unlock immediately.
  Now we completely rely on extent io tree locking.

- Extra bitmap update along with page status update
  Now page dirty and writeback is controlled by
  btrfs_subpage::dirty_bitmap and btrfs_subpage::writeback_bitmap.
  They both follow the schema that any sector is dirty/writeback, then
  the full page gets dirty/writeback.

- When to update the nr_written number
  Now we take a shortcut, if we have cleared the last dirty bit of the
  page, we update nr_written.
  This is not completely perfect, but should emulate the old behavior
  well enough.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19 17:25:22 +02:00
Qu Wenruo
2f3186d8ee btrfs: introduce end_bio_subpage_eb_writepage() function
The new function, end_bio_subpage_eb_writepage(), will handle the
metadata writeback endio.

The major differences involved are:

- How to grab extent buffer
  Now page::private is a pointer to btrfs_subpage, we can no longer grab
  extent buffer directly.
  Thus we need to use the bv_offset to locate the extent buffer manually
  and iterate through the whole range.

- Use btrfs_subpage_end_writeback() caller
  This helper will handle the subpage writeback for us.

Since this function is executed under endio context, when grabbing
extent buffers it can't grab eb->refs_lock as that lock is not designed
to be grabbed under hardirq context.

So here introduce a helper, find_extent_buffer_nolock(), for such
situation, and convert find_extent_buffer() to use that helper.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19 17:25:22 +02:00
Josef Bacik
fb686c6824 btrfs: check return value of btrfs_commit_transaction in relocation
There are a few places where we don't check the return value of
btrfs_commit_transaction in relocation.c.  Thankfully all these places
have straightforward error handling, so simply change all of the sites
at once.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19 17:25:22 +02:00
Josef Bacik
24213fa46c btrfs: do proper error handling in merge_reloc_roots
We have a BUG_ON() if we get an error back from btrfs_get_fs_root().
This honestly should never fail, as at this point we have a solid
coordination of fs root to reloc root, and these roots will all be in
memory.  But in the name of killing BUG_ON()'s remove these and handle
the error condition properly, ASSERT()'ing for developers.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19 17:25:22 +02:00
Josef Bacik
8717cf440d btrfs: handle extent corruption with select_one_root properly
In corruption cases we could have paths from a block up to no root at
all, and thus we'll BUG_ON(!root) in select_one_root.  Handle this by
adding an ASSERT() for developers, and returning an error for normal
users.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19 17:25:22 +02:00
Josef Bacik
e0b085b0b0 btrfs: cleanup error handling in prepare_to_merge
This probably can't happen even with a corrupt file system, because we
would have failed much earlier on than here.  However there's no reason
we can't just check and bail out as appropriate, so do that and convert
the correctness BUG_ON() to an ASSERT().

Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ add comment ]
Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19 17:25:22 +02:00
Josef Bacik
57a304cfd4 btrfs: do not panic in __add_reloc_root
If we have a duplicate entry for a reloc root then we could have fs
corruption that resulted in a double allocation.  Since this shouldn't
happen unless there is corruption, add an ASSERT(ret != -EEXIST) to all
of the callers of __add_reloc_root() to catch any logic mistakes for
developers, otherwise normal error handling will happen for normal
users.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19 17:25:22 +02:00
Josef Bacik
3c9258632c btrfs: handle __add_reloc_root failures in btrfs_recover_relocation
We can already handle errors appropriately from this function, deal with
an error coming from __add_reloc_root appropriately.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ add comment ]
Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19 17:25:22 +02:00
Josef Bacik
790c1b8cd4 btrfs: do proper error handling in create_reloc_inode
We already handle some errors in this function, and the callers do the
correct error handling, so clean up the rest of the function to do the
appropriate error handling.

There's a little extra work that needs to be done here, as we create the
inode item before we create the orphan item.  We could potentially add
the orphan item, but if we failed to create the inode item we would have
to abort the transaction.

Instead add a helper to delete the inode item we created in the case
that we're unable to look up the inode (this would likely be caused by
an ENOMEM), which if it succeeds means we can avoid a transaction abort
in this particular error case.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19 17:25:21 +02:00
Josef Bacik
24cd638902 btrfs: remove the extent item sanity checks in relocate_block_group
These checks are all taken care of for us by the tree checker code:

- the flags don't change or are updated consistently
- the v0 extent item format is invalid and caught in many other places
  too

Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ update changelog ]
Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19 17:25:21 +02:00
Josef Bacik
0ebb6bbbd4 btrfs: tree-checker: check for BTRFS_BLOCK_FLAG_FULL_BACKREF being set improperly
We need to validate that a data extent item does not have the
FULL_BACKREF flag set on its flags.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19 17:25:21 +02:00
Josef Bacik
eb6b7fb4b5 btrfs: handle extent reference errors in do_relocation
We can already deal with errors appropriately from do_relocation, simply
handle any errors that come from changing the refs at this point
cleanly.  We have to abort the transaction if we fail here as we've
modified metadata at this point.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19 17:25:21 +02:00
Josef Bacik
253e258c34 btrfs: handle errors in reference count manipulation in replace_path
If any of the reference count manipulation stuff fails in replace_path
we need to abort the transaction, as we've modified the blocks already.
We can simply break at this point and everything will be cleaned up.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19 17:25:21 +02:00
Josef Bacik
0e9873e2fe btrfs: handle btrfs_search_slot failure in replace_path
The search can fail for various reasons, in case of errors there's no
cleanup to be done so we can pass the error to the caller, adjusting for
the case where the key is not found and search slot returns 1.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ update changelog ]
Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19 17:25:21 +02:00
Josef Bacik
45b87c5d25 btrfs: handle btrfs_cow_block errors in replace_path
If we error out COWing the root node when doing a replace_path then we
simply unlock and free the buffer and return the error.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19 17:25:21 +02:00
Josef Bacik
7a9213a935 btrfs: convert logic BUG_ON()'s in replace_path to ASSERT()'s
A few BUG_ON()'s in replace_path are purely to keep us from making
logical mistakes, so replace them with ASSERT()'s.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19 17:25:21 +02:00
Josef Bacik
592fbcd50c btrfs: do proper error handling in btrfs_update_reloc_root
We call btrfs_update_root in btrfs_update_reloc_root, which can fail for
all sorts of reasons, including IO errors.  Instead of panicing the box
lets return the error, now that all callers properly handle those
errors.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19 17:25:21 +02:00
Josef Bacik
bbae13f8ab btrfs: handle btrfs_update_reloc_root failure in prepare_to_merge
btrfs_update_reloc_root will will return errors in the future, so handle
an error properly in prepare_to_merge.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19 17:25:21 +02:00
Josef Bacik
7934133fae btrfs: handle btrfs_update_reloc_root failure in insert_dirty_subvol
btrfs_update_reloc_root will will return errors in the future, so handle
the error properly in insert_dirty_subvol.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19 17:25:21 +02:00
Josef Bacik
ac54da6c37 btrfs: change insert_dirty_subvol to return errors
This will be able to return errors in the future, so change it to return
an error and handle the errors appropriately.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19 17:25:21 +02:00
Josef Bacik
2dd8298eb3 btrfs: handle btrfs_update_reloc_root failure in commit_fs_roots
btrfs_update_reloc_root will will return errors in the future, so handle
the error properly in commit_fs_roots.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19 17:25:20 +02:00
Josef Bacik
39200e5908 btrfs: validate root::reloc_root after recording root in trans
If we fail to setup a root->reloc_root in a different thread that path
will error out, however it still leaves root->reloc_root NULL but would
still appear set up in the transaction.  Subsequent calls to
btrfs_record_root_in_transaction would succeed without attempting to
create the reloc root, as the transid has already been updated.

Handle this case by making sure we have a root->reloc_root set after a
btrfs_record_root_in_transaction call so we don't end up dereferencing a
NULL pointer.

Reported-by: Zygo Blaxell <ce3g8jdj@umail.furryterror.org>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19 17:25:20 +02:00
Josef Bacik
84c50ba521 btrfs: do proper error handling in create_reloc_root
We do memory allocations here, read blocks from disk, all sorts of
operations that could easily fail at any given point.  Instead of
panicing the box, simply return the error back up the chain, all callers
at this point have proper error handling.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19 17:25:20 +02:00
Josef Bacik
00bb36a0e7 btrfs: have proper error handling in btrfs_init_reloc_root
create_reloc_root will return errors in the future, and __add_reloc_root
can return ENOMEM or EEXIST, so handle these errors properly.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ add comment ]
Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19 17:25:20 +02:00
Josef Bacik
03a7e111a9 btrfs: return an error from btrfs_record_root_in_trans
We can create a reloc root when we record the root in the trans, which
can fail for all sorts of different reasons.  Propagate this error up
the chain of callers.  Future patches will fix the callers of
btrfs_record_root_in_trans() to handle the error.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19 17:25:20 +02:00
Josef Bacik
f0118cb6bc btrfs: handle record_root_in_trans failure in create_pending_snapshot
record_root_in_trans can currently fail, so handle this failure
properly.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19 17:25:20 +02:00
Josef Bacik
1409e6cc74 btrfs: handle record_root_in_trans failure in btrfs_record_root_in_trans
record_root_in_trans can fail currently, handle this failure properly.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19 17:25:20 +02:00
Josef Bacik
1c442d2246 btrfs: handle record_root_in_trans failure in qgroup_account_snapshot
record_root_in_trans can fail currently, so handle this failure
properly.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19 17:25:20 +02:00
Josef Bacik
68075ea8d7 btrfs: handle btrfs_record_root_in_trans failure in start_transaction
btrfs_record_root_in_trans will return errors in the future, so handle
the error properly in start_transaction.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ add comment ]
Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19 17:25:20 +02:00
Josef Bacik
d18c7bd95c btrfs: handle btrfs_record_root_in_trans failure in relocate_tree_block
btrfs_record_root_in_trans will return errors in the future, so handle
the error properly in relocate_tree_block.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19 17:25:20 +02:00
Josef Bacik
221581e485 btrfs: handle btrfs_record_root_in_trans failure in create_subvol
btrfs_record_root_in_trans will return errors in the future, so handle
the error properly in create_subvol.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19 17:25:20 +02:00
Josef Bacik
2002ae112a btrfs: handle btrfs_record_root_in_trans failure in btrfs_recover_log_trees
btrfs_record_root_in_trans will return errors in the future, so handle
the error properly in btrfs_recover_log_trees.

This appears tricky, however we have a reference count on the
destination root, so if this fails we need to continue on in the loop to
make sure the proper cleanup is done.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ add comment ]
Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19 17:25:20 +02:00
Josef Bacik
2731f5186b btrfs: handle btrfs_record_root_in_trans failure in btrfs_delete_subvolume
btrfs_record_root_in_trans will return errors in the future, so handle
the error properly in btrfs_delete_subvolume.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19 17:25:19 +02:00
Josef Bacik
b0fec6fd33 btrfs: handle btrfs_record_root_in_trans failure in btrfs_rename
btrfs_record_root_in_trans will return errors in the future, so handle
the error properly in btrfs_rename.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19 17:25:19 +02:00
Josef Bacik
00aa8e87c9 btrfs: handle btrfs_record_root_in_trans failure in btrfs_rename_exchange
btrfs_record_root_in_trans will return errors in the future, so handle
the error properly in btrfs_rename_exchange.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19 17:25:19 +02:00
Josef Bacik
404bccbcaa btrfs: do proper error handling in record_reloc_root_in_trans
Generally speaking this shouldn't ever fail, the corresponding fs root
for the reloc root will already be in memory, so we won't get ENOMEM
here.

However if there is no corresponding root for the reloc root then we
could get ENOMEM when we try to allocate it or we could get ENOENT
when we look it up and see that it doesn't exist.

Convert these BUG_ON()'s into ASSERT()'s and add proper error handling
for the case of corruption.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19 17:25:19 +02:00