<feed xmlns='http://www.w3.org/2005/Atom'>
<title>kernel/git/stable/linux.git/fs/btrfs/send.c, branch linux-5.8.y</title>
<subtitle>Linux kernel stable tree</subtitle>
<id>https://git.rulkc.org/pub/scm/linux/kernel/git/stable/linux.git/atom?h=linux-5.8.y</id>
<link rel='self' href='https://git.rulkc.org/pub/scm/linux/kernel/git/stable/linux.git/atom?h=linux-5.8.y'/>
<link rel='alternate' type='text/html' href='https://git.rulkc.org/pub/scm/linux/kernel/git/stable/linux.git/'/>
<updated>2020-06-03T02:59:25+00:00</updated>
<entry>
<title>Merge tag 'for-5.8-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux</title>
<updated>2020-06-03T02:59:25+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2020-06-03T02:59:25+00:00</published>
<link rel='alternate' type='text/html' href='https://git.rulkc.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=f3cdc8ae116e27d84e1f33c7a2995960cebb73ac'/>
<id>urn:sha1:f3cdc8ae116e27d84e1f33c7a2995960cebb73ac</id>
<content type='text'>
Pull btrfs updates from David Sterba:
 "Highlights:

   - speedup dead root detection during orphan cleanup, eg. when there
     are many deleted subvolumes waiting to be cleaned, the trees are
     now looked up in radix tree instead of a O(N^2) search

   - snapshot creation with inherited qgroup will mark the qgroup
     inconsistent, requires a rescan

   - send will emit file capabilities after chown, this produces a
     stream that does not need postprocessing to set the capabilities
     again

   - direct io ported to iomap infrastructure, cleaned up and simplified
     code, notably removing last use of struct buffer_head in btrfs code

  Core changes:

   - factor out backreference iteration, to be used by ordinary
     backreferences and relocation code

   - improved global block reserve utilization
      * better logic to serialize requests
      * increased maximum available for unlink
      * improved handling on large pages (64K)

   - direct io cleanups and fixes
      * simplify layering, where cloned bios were unnecessarily created
        for some cases
      * error handling fixes (submit, endio)
      * remove repair worker thread, used to avoid deadlocks during
        repair

   - refactored block group reading code, preparatory work for new type
     of block group storage that should improve mount time on large
     filesystems

  Cleanups:

   - cleaned up (and slightly sped up) set/get helpers for metadata data
     structure members

   - root bit REF_COWS got renamed to SHAREABLE to reflect the that the
     blocks of the tree get shared either among subvolumes or with the
     relocation trees

  Fixes:

   - when subvolume deletion fails due to ENOSPC, the filesystem is not
     turned read-only

   - device scan deals with devices from other filesystems that changed
     ownership due to overwrite (mkfs)

   - fix a race between scrub and block group removal/allocation

   - fix long standing bug of a runaway balance operation, printing the
     same line to the syslog, caused by a stale status bit on a reloc
     tree that prevented progress

   - fix corrupt log due to concurrent fsync of inodes with shared
     extents

   - fix space underflow for NODATACOW and buffered writes when it for
     some reason needs to fallback to COW mode"

* tag 'for-5.8-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: (133 commits)
  btrfs: fix space_info bytes_may_use underflow during space cache writeout
  btrfs: fix space_info bytes_may_use underflow after nocow buffered write
  btrfs: fix wrong file range cleanup after an error filling dealloc range
  btrfs: remove redundant local variable in read_block_for_search
  btrfs: open code key_search
  btrfs: split btrfs_direct_IO to read and write part
  btrfs: remove BTRFS_INODE_READDIO_NEED_LOCK
  fs: remove dio_end_io()
  btrfs: switch to iomap_dio_rw() for dio
  iomap: remove lockdep_assert_held()
  iomap: add a filesystem hook for direct I/O bio submission
  fs: export generic_file_buffered_read()
  btrfs: turn space cache writeout failure messages into debug messages
  btrfs: include error on messages about failure to write space/inode caches
  btrfs: remove useless 'fail_unlock' label from btrfs_csum_file_blocks()
  btrfs: do not ignore error from btrfs_next_leaf() when inserting checksums
  btrfs: make checksum item extension more efficient
  btrfs: fix corrupt log due to concurrent fsync of inodes with shared extents
  btrfs: unexport btrfs_compress_set_level()
  btrfs: simplify iget helpers
  ...
</content>
</entry>
<entry>
<title>btrfs: simplify iget helpers</title>
<updated>2020-05-25T09:25:37+00:00</updated>
<author>
<name>David Sterba</name>
<email>dsterba@suse.com</email>
</author>
<published>2020-05-15T17:35:59+00:00</published>
<link rel='alternate' type='text/html' href='https://git.rulkc.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=0202e83fdab05b3bf641804afea57a2bfcbcbd70'/>
<id>urn:sha1:0202e83fdab05b3bf641804afea57a2bfcbcbd70</id>
<content type='text'>
The inode lookup starting at btrfs_iget takes the full location key,
while only the objectid is used to match the inode, because the lookup
happens inside the given root thus the inode number is unique.
The entire location key is properly set up in btrfs_init_locked_inode.

Simplify the helpers and pass only inode number, renaming it to 'ino'
instead of 'objectid'. This allows to remove temporary variables key,
saving some stack space.

Signed-off-by: David Sterba &lt;dsterba@suse.com&gt;
</content>
</entry>
<entry>
<title>btrfs: simplify root lookup by id</title>
<updated>2020-05-25T09:25:36+00:00</updated>
<author>
<name>David Sterba</name>
<email>dsterba@suse.com</email>
</author>
<published>2020-05-15T17:35:55+00:00</published>
<link rel='alternate' type='text/html' href='https://git.rulkc.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=56e9357a1e8167134388d4c70654795353765c7b'/>
<id>urn:sha1:56e9357a1e8167134388d4c70654795353765c7b</id>
<content type='text'>
The main function to lookup a root by its id btrfs_get_fs_root takes the
whole key, while only using the objectid. The value of offset is preset
to (u64)-1 but not actually used until btrfs_find_root that does the
actual search.

Switch btrfs_get_fs_root to use only objectid and remove all local
variables that existed just for the lookup. The actual key for search is
set up in btrfs_get_fs_root, reusing another key variable.

Signed-off-by: David Sterba &lt;dsterba@suse.com&gt;
</content>
</entry>
<entry>
<title>btrfs: send: emit file capabilities after chown</title>
<updated>2020-05-25T09:25:30+00:00</updated>
<author>
<name>Marcos Paulo de Souza</name>
<email>mpdesouza@suse.com</email>
</author>
<published>2020-05-11T02:15:07+00:00</published>
<link rel='alternate' type='text/html' href='https://git.rulkc.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=89efda52e6b6930f80f5adda9c3c9edfb1397191'/>
<id>urn:sha1:89efda52e6b6930f80f5adda9c3c9edfb1397191</id>
<content type='text'>
Whenever a chown is executed, all capabilities of the file being touched
are lost.  When doing incremental send with a file with capabilities,
there is a situation where the capability can be lost on the receiving
side. The sequence of actions bellow shows the problem:

  $ mount /dev/sda fs1
  $ mount /dev/sdb fs2

  $ touch fs1/foo.bar
  $ setcap cap_sys_nice+ep fs1/foo.bar
  $ btrfs subvolume snapshot -r fs1 fs1/snap_init
  $ btrfs send fs1/snap_init | btrfs receive fs2

  $ chgrp adm fs1/foo.bar
  $ setcap cap_sys_nice+ep fs1/foo.bar

  $ btrfs subvolume snapshot -r fs1 fs1/snap_complete
  $ btrfs subvolume snapshot -r fs1 fs1/snap_incremental

  $ btrfs send fs1/snap_complete | btrfs receive fs2
  $ btrfs send -p fs1/snap_init fs1/snap_incremental | btrfs receive fs2

At this point, only a chown was emitted by "btrfs send" since only the
group was changed. This makes the cap_sys_nice capability to be dropped
from fs2/snap_incremental/foo.bar

To fix that, only emit capabilities after chown is emitted. The current
code first checks for xattrs that are new/changed, emits them, and later
emit the chown. Now, __process_new_xattr skips capabilities, letting
only finish_inode_if_needed to emit them, if they exist, for the inode
being processed.

This behavior was being worked around in "btrfs receive" side by caching
the capability and only applying it after chown. Now, xattrs are only
emmited _after_ chown, making that workaround not needed anymore.

Link: https://github.com/kdave/btrfs-progs/issues/202
CC: stable@vger.kernel.org # 4.4+
Suggested-by: Filipe Manana &lt;fdmanana@suse.com&gt;
Reviewed-by: Filipe Manana &lt;fdmanana@suse.com&gt;
Signed-off-by: Marcos Paulo de Souza &lt;mpdesouza@suse.com&gt;
Signed-off-by: David Sterba &lt;dsterba@suse.com&gt;
</content>
</entry>
<entry>
<title>btrfs_ioctl_send(): don't bother with access_ok()</title>
<updated>2020-05-09T19:59:10+00:00</updated>
<author>
<name>Al Viro</name>
<email>viro@zeniv.linux.org.uk</email>
</author>
<published>2020-02-19T14:35:32+00:00</published>
<link rel='alternate' type='text/html' href='https://git.rulkc.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=502fd722fe1ed0133d1108bff1d5911f46de6641'/>
<id>urn:sha1:502fd722fe1ed0133d1108bff1d5911f46de6641</id>
<content type='text'>
we do copy_from_user() on that range anyway

Signed-off-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
</content>
</entry>
<entry>
<title>btrfs: kill the subvol_srcu</title>
<updated>2020-03-23T16:02:00+00:00</updated>
<author>
<name>Josef Bacik</name>
<email>josef@toxicpanda.com</email>
</author>
<published>2020-02-14T21:11:47+00:00</published>
<link rel='alternate' type='text/html' href='https://git.rulkc.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=c75e839414d3610e6487ae3145199c500d55f7f7'/>
<id>urn:sha1:c75e839414d3610e6487ae3145199c500d55f7f7</id>
<content type='text'>
Now that we have proper root ref counting everywhere we can kill the
subvol_srcu.

* removal of fs_info::subvol_srcu reduces size of fs_info by 1176 bytes

* the refcount_t used for the references checks for accidental 0-&gt;1
  in cases where the root lifetime would not be properly protected

* there's a leak detector for roots to catch unfreed roots at umount
  time

* SRCU served us well over the years but is was not a proper
  synchronization mechanism for some cases

Signed-off-by: Josef Bacik &lt;josef@toxicpanda.com&gt;
Reviewed-by: David Sterba &lt;dsterba@suse.com&gt;
[ update changelog ]
Signed-off-by: David Sterba &lt;dsterba@suse.com&gt;
</content>
</entry>
<entry>
<title>btrfs: add helper to get the end offset of a file extent item</title>
<updated>2020-03-23T16:01:56+00:00</updated>
<author>
<name>Filipe Manana</name>
<email>fdmanana@suse.com</email>
</author>
<published>2020-03-09T12:41:06+00:00</published>
<link rel='alternate' type='text/html' href='https://git.rulkc.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=a5eeb3d17b979f7afe3ac68fe049ce8b0a039b03'/>
<id>urn:sha1:a5eeb3d17b979f7afe3ac68fe049ce8b0a039b03</id>
<content type='text'>
Getting the end offset for a file extent item requires a bit of code since
the extent can be either inline or regular/prealloc. There are some places
all over the code base that open code this logic and in another patch
later in this series it will be needed again. Therefore encapsulate this
logic in a helper function and use it.

Reviewed-by: Josef Bacik &lt;josef@toxicpanda.com&gt;
Signed-off-by: Filipe Manana &lt;fdmanana@suse.com&gt;
Reviewed-by: David Sterba &lt;dsterba@suse.com&gt;
Signed-off-by: David Sterba &lt;dsterba@suse.com&gt;
</content>
</entry>
<entry>
<title>btrfs: rename btrfs_put_fs_root and btrfs_grab_fs_root</title>
<updated>2020-03-23T16:01:33+00:00</updated>
<author>
<name>Josef Bacik</name>
<email>josef@toxicpanda.com</email>
</author>
<published>2020-01-24T14:33:01+00:00</published>
<link rel='alternate' type='text/html' href='https://git.rulkc.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=0024652895e3479cd0d372f63b57d9581a0bdd38'/>
<id>urn:sha1:0024652895e3479cd0d372f63b57d9581a0bdd38</id>
<content type='text'>
We are now using these for all roots, rename them to btrfs_put_root()
and btrfs_grab_root();

Reviewed-by: Nikolay Borisov &lt;nborisov@suse.com&gt;
Signed-off-by: Josef Bacik &lt;josef@toxicpanda.com&gt;
Reviewed-by: David Sterba &lt;dsterba@suse.com&gt;
Signed-off-by: David Sterba &lt;dsterba@suse.com&gt;
</content>
</entry>
<entry>
<title>btrfs: push btrfs_grab_fs_root into btrfs_get_fs_root</title>
<updated>2020-03-23T16:01:32+00:00</updated>
<author>
<name>Josef Bacik</name>
<email>josef@toxicpanda.com</email>
</author>
<published>2020-01-24T14:32:56+00:00</published>
<link rel='alternate' type='text/html' href='https://git.rulkc.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=bc44d7c4b2b179c4b74fba208b9908e2ecbc1b4d'/>
<id>urn:sha1:bc44d7c4b2b179c4b74fba208b9908e2ecbc1b4d</id>
<content type='text'>
Now that all callers of btrfs_get_fs_root are subsequently calling
btrfs_grab_fs_root and handling dropping the ref when they are done
appropriately, go ahead and push btrfs_grab_fs_root up into
btrfs_get_fs_root.

Signed-off-by: Josef Bacik &lt;josef@toxicpanda.com&gt;
Reviewed-by: David Sterba &lt;dsterba@suse.com&gt;
Signed-off-by: David Sterba &lt;dsterba@suse.com&gt;
</content>
</entry>
<entry>
<title>btrfs: hold a ref on the root in btrfs_ioctl_send</title>
<updated>2020-03-23T16:01:31+00:00</updated>
<author>
<name>Josef Bacik</name>
<email>josef@toxicpanda.com</email>
</author>
<published>2020-01-24T14:32:48+00:00</published>
<link rel='alternate' type='text/html' href='https://git.rulkc.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=6f9a3da5da9e7e59f3a5a5909aab5f680fe919c9'/>
<id>urn:sha1:6f9a3da5da9e7e59f3a5a5909aab5f680fe919c9</id>
<content type='text'>
We lookup all the clone roots and the parent root for send, so we need
to hold refs on all of these roots while we're processing them.

Signed-off-by: Josef Bacik &lt;josef@toxicpanda.com&gt;
Reviewed-by: David Sterba &lt;dsterba@suse.com&gt;
Signed-off-by: David Sterba &lt;dsterba@suse.com&gt;
</content>
</entry>
</feed>
