linux.git/fs/ext2/inode.c, branch v6.5

ext2: Move direct-io to use iomap

2023-05-16T09:32:42+00:00

This patch converts ext2 direct-io path to iomap interface.
- This also takes care of DIO_SKIP_HOLES part in which we return -ENOTBLK
  from ext2_iomap_begin(), in case if the write is done on a hole.
- This fallbacks to buffered-io in case of DIO_SKIP_HOLES or in case of
  a partial write or if any error is detected in ext2_iomap_end().
  We try to return -ENOTBLK in such cases.
- For any unaligned or extending DIO writes, we pass
  IOMAP_DIO_FORCE_WAIT flag to ensure synchronous writes.
- For extending writes we set IOMAP_F_DIRTY in ext2_iomap_begin because
  otherwise with dsync writes on devices that support FUA, generic_write_sync
  won't be called and we might miss inode metadata updates.
- Since ext2 already now uses _nolock vartiant of sync write. Hence
  there is no inode lock problem with iomap in this patch.
- ext2_iomap_ops are now being shared by DIO, DAX & fiemap path

Tested-by: Disha Goel 
Reviewed-by: Christoph Hellwig 
Signed-off-by: Ritesh Harjani (IBM) 
Signed-off-by: Jan Kara 
Message-Id: <610b672a52f2a7ff6dc550fd14d0f995806232a5.1682069716.git.ritesh.list@gmail.com>

ext2/dax: Fix ext2_setsize when len is page aligned

2023-05-16T09:32:42+00:00

PAGE_ALIGN(x) macro gives the next highest value which is multiple of
pagesize. But if x is already page aligned then it simply returns x.
So, if x passed is 0 in dax_zero_range() function, that means the
length gets passed as 0 to ->iomap_begin().

In ext2 it then calls ext2_get_blocks -> max_blocks as 0 and hits bug_on
here in ext2_get_blocks().
	BUG_ON(maxblocks == 0);

Instead we should be calling dax_truncate_page() here which takes
care of it. i.e. it only calls dax_zero_range if the offset is not
page/block aligned.

This can be easily triggered with following on fsdax mounted pmem
device.

dd if=/dev/zero of=file count=1 bs=512
truncate -s 0 file

[79.525838] EXT2-fs (pmem0): DAX enabled. Warning: EXPERIMENTAL, use at your own risk
[79.529376] ext2 filesystem being mounted at /mnt1/test supports timestamps until 2038 (0x7fffffff)
[93.793207] ------------[ cut here ]------------
[93.795102] kernel BUG at fs/ext2/inode.c:637!
[93.796904] invalid opcode: 0000 [#1] PREEMPT SMP PTI
[93.798659] CPU: 0 PID: 1192 Comm: truncate Not tainted 6.3.0-rc2-xfstests-00056-g131086faa369 #139
[93.806459] RIP: 0010:ext2_get_blocks.constprop.0+0x524/0x610
<...>
[93.835298] Call Trace:
[93.836253]  
[93.837103]  ? lock_acquire+0xf8/0x110
[93.838479]  ? d_lookup+0x69/0xd0
[93.839779]  ext2_iomap_begin+0xa7/0x1c0
[93.841154]  iomap_iter+0xc7/0x150
[93.842425]  dax_zero_range+0x6e/0xa0
[93.843813]  ext2_setsize+0x176/0x1b0
[93.845164]  ext2_setattr+0x151/0x200
[93.846467]  notify_change+0x341/0x4e0
[93.847805]  ? lock_acquire+0xf8/0x110
[93.849143]  ? do_truncate+0x74/0xe0
[93.850452]  ? do_truncate+0x84/0xe0
[93.851739]  do_truncate+0x84/0xe0
[93.852974]  do_sys_ftruncate+0x2b4/0x2f0
[93.854404]  do_syscall_64+0x3f/0x90
[93.855789]  entry_SYSCALL_64_after_hwframe+0x72/0xdc

CC: stable@vger.kernel.org
Fixes: 2aa3048e03d3 ("iomap: switch iomap_zero_range to use iomap_iter")
Reviewed-by: Darrick J. Wong 
Signed-off-by: Ritesh Harjani (IBM) 
Signed-off-by: Jan Kara 
Message-Id: <046a58317f29d9603d1068b2bbae47c2332c17ae.1682069716.git.ritesh.list@gmail.com>

quota: port to mnt_idmap

2023-01-19T08:24:29+00:00

Convert to struct mnt_idmap.

Last cycle we merged the necessary infrastructure in
256c8aed2b42 ("fs: introduce dedicated idmap type for mounts").
This is just the conversion to struct mnt_idmap.

Currently we still pass around the plain namespace that was attached to a
mount. This is in general pretty convenient but it makes it easy to
conflate namespaces that are relevant on the filesystem with namespaces
that are relevent on the mount level. Especially for non-vfs developers
without detailed knowledge in this area this can be a potential source for
bugs.

Once the conversion to struct mnt_idmap is done all helpers down to the
really low-level helpers will take a struct mnt_idmap argument instead of
two namespace arguments. This way it becomes impossible to conflate the two
eliminating the possibility of any bugs. All of the vfs and all filesystems
only operate on struct mnt_idmap.

Acked-by: Dave Chinner 
Reviewed-by: Christoph Hellwig 
Signed-off-by: Christian Brauner (Microsoft)

fs: port ->set_acl() to pass mnt_idmap

2023-01-19T08:24:27+00:00

Convert to struct mnt_idmap.

Last cycle we merged the necessary infrastructure in
256c8aed2b42 ("fs: introduce dedicated idmap type for mounts").
This is just the conversion to struct mnt_idmap.

Currently we still pass around the plain namespace that was attached to a
mount. This is in general pretty convenient but it makes it easy to
conflate namespaces that are relevant on the filesystem with namespaces
that are relevent on the mount level. Especially for non-vfs developers
without detailed knowledge in this area this can be a potential source for
bugs.

Once the conversion to struct mnt_idmap is done all helpers down to the
really low-level helpers will take a struct mnt_idmap argument instead of
two namespace arguments. This way it becomes impossible to conflate the two
eliminating the possibility of any bugs. All of the vfs and all filesystems
only operate on struct mnt_idmap.

Acked-by: Dave Chinner 
Reviewed-by: Christoph Hellwig 
Signed-off-by: Christian Brauner (Microsoft)

fs: port ->getattr() to pass mnt_idmap

2023-01-19T08:24:25+00:00

Convert to struct mnt_idmap.

Last cycle we merged the necessary infrastructure in
256c8aed2b42 ("fs: introduce dedicated idmap type for mounts").
This is just the conversion to struct mnt_idmap.

Currently we still pass around the plain namespace that was attached to a
mount. This is in general pretty convenient but it makes it easy to
conflate namespaces that are relevant on the filesystem with namespaces
that are relevent on the mount level. Especially for non-vfs developers
without detailed knowledge in this area this can be a potential source for
bugs.

Once the conversion to struct mnt_idmap is done all helpers down to the
really low-level helpers will take a struct mnt_idmap argument instead of
two namespace arguments. This way it becomes impossible to conflate the two
eliminating the possibility of any bugs. All of the vfs and all filesystems
only operate on struct mnt_idmap.

Acked-by: Dave Chinner 
Reviewed-by: Christoph Hellwig 
Signed-off-by: Christian Brauner (Microsoft)

fs: port ->setattr() to pass mnt_idmap

2023-01-19T08:24:02+00:00

Convert to struct mnt_idmap.

Last cycle we merged the necessary infrastructure in
256c8aed2b42 ("fs: introduce dedicated idmap type for mounts").
This is just the conversion to struct mnt_idmap.

Currently we still pass around the plain namespace that was attached to a
mount. This is in general pretty convenient but it makes it easy to
conflate namespaces that are relevant on the filesystem with namespaces
that are relevent on the mount level. Especially for non-vfs developers
without detailed knowledge in this area this can be a potential source for
bugs.

Once the conversion to struct mnt_idmap is done all helpers down to the
really low-level helpers will take a struct mnt_idmap argument instead of
two namespace arguments. This way it becomes impossible to conflate the two
eliminating the possibility of any bugs. All of the vfs and all filesystems
only operate on struct mnt_idmap.

Acked-by: Dave Chinner 
Reviewed-by: Christoph Hellwig 
Signed-off-by: Christian Brauner (Microsoft)

Merge tag 'fixes_for_v6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs

2022-12-13T04:32:50+00:00

Pull udf and ext2 fixes from Jan Kara:

 - a couple of smaller cleanups and fixes for ext2

 - fixes of a data corruption issues in udf when handling holes and
   preallocation extents

 - fixes and cleanups of several smaller issues in udf

 - add maintainer entry for isofs

* tag 'fixes_for_v6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
  udf: Fix extending file within last block
  udf: Discard preallocation before extending file with a hole
  udf: Do not bother looking for prealloc extents if i_lenExtents matches i_size
  udf: Fix preallocation discarding at indirect extent boundary
  udf: Increase UDF_MAX_READ_VERSION to 0x0260
  fs/ext2: Fix code indentation
  ext2: unbugger ext2_empty_dir()
  udf: remove ->writepage
  ext2: remove ->writepage
  ext2: Don't flush page immediately for DIRSYNC directories
  ext2: Fix some kernel-doc warnings
  maintainers: Add ISOFS entry
  udf: Avoid double brelse() in udf_rename()
  fs: udf: Optimize udf_free_in_core_inode and udf_find_fileset function

ext2: remove ->writepage

2022-11-21T10:05:01+00:00

->writepage is a very inefficient method to write back data, and only
used through write_cache_pages or as a fallback when no ->migrate_folio
method is present.

Signed-off-by: Christoph Hellwig 
Signed-off-by: Jan Kara

fs: pass dentry to set acl method

2022-10-19T10:55:42+00:00

The current way of setting and getting posix acls through the generic
xattr interface is error prone and type unsafe. The vfs needs to
interpret and fixup posix acls before storing or reporting it to
userspace. Various hacks exist to make this work. The code is hard to
understand and difficult to maintain in it's current form. Instead of
making this work by hacking posix acls through xattr handlers we are
building a dedicated posix acl api around the get and set inode
operations. This removes a lot of hackiness and makes the codepaths
easier to maintain. A lot of background can be found in [1].

Since some filesystem rely on the dentry being available to them when
setting posix acls (e.g., 9p and cifs) they cannot rely on set acl inode
operation. But since ->set_acl() is required in order to use the generic
posix acl xattr handlers filesystems that do not implement this inode
operation cannot use the handler and need to implement their own
dedicated posix acl handlers.

Update the ->set_acl() inode method to take a dentry argument. This
allows all filesystems to rely on ->set_acl().

As far as I can tell all codepaths can be switched to rely on the dentry
instead of just the inode. Note that the original motivation for passing
the dentry separate from the inode instead of just the dentry in the
xattr handlers was because of security modules that call
security_d_instantiate(). This hook is called during
d_instantiate_new(), d_add(), __d_instantiate_anon(), and
d_splice_alias() to initialize the inode's security context and possibly
to set security.* xattrs. Since this only affects security.* xattrs this
is completely irrelevant for posix acls.

Link: https://lore.kernel.org/all/20220801145520.1532837-1-brauner@kernel.org [1]
Reviewed-by: Christoph Hellwig 
Signed-off-by: Christian Brauner (Microsoft)

Merge tag 'folio-6.0' of git://git.infradead.org/users/willy/pagecache

2022-08-03T17:35:43+00:00

Pull folio updates from Matthew Wilcox:

 - Fix an accounting bug that made NR_FILE_DIRTY grow without limit
   when running xfstests

 - Convert more of mpage to use folios

 - Remove add_to_page_cache() and add_to_page_cache_locked()

 - Convert find_get_pages_range() to filemap_get_folios()

 - Improvements to the read_cache_page() family of functions

 - Remove a few unnecessary checks of PageError

 - Some straightforward filesystem conversions to use folios

 - Split PageMovable users out from address_space_operations into
   their own movable_operations

 - Convert aops->migratepage to aops->migrate_folio

 - Remove nobh support (Christoph Hellwig)

* tag 'folio-6.0' of git://git.infradead.org/users/willy/pagecache: (78 commits)
  fs: remove the NULL get_block case in mpage_writepages
  fs: don't call ->writepage from __mpage_writepage
  fs: remove the nobh helpers
  jfs: stop using the nobh helper
  ext2: remove nobh support
  ntfs3: refactor ntfs_writepages
  mm/folio-compat: Remove migration compatibility functions
  fs: Remove aops->migratepage()
  secretmem: Convert to migrate_folio
  hugetlb: Convert to migrate_folio
  aio: Convert to migrate_folio
  f2fs: Convert to filemap_migrate_folio()
  ubifs: Convert to filemap_migrate_folio()
  btrfs: Convert btrfs_migratepage to migrate_folio
  mm/migrate: Add filemap_migrate_folio()
  mm/migrate: Convert migrate_page() to migrate_folio()
  nfs: Convert to migrate_folio
  btrfs: Convert btree_migratepage to migrate_folio
  mm/migrate: Convert expected_page_refs() to folio_expected_refs()
  mm/migrate: Convert buffer_migrate_page() to buffer_migrate_folio()
  ...