linux-toradex.git/fs/erofs/inode.c, branch v6.7

erofs: simplify erofs_read_inode()

2023-11-17T11:55:34+00:00

After commit 1c7f49a76773 ("erofs: tidy up EROFS on-disk naming"),
there is a unique `union erofs_inode_i_u` so that we could parse
the union directly.

Besides, it also replaces `inode->i_sb` with `sb` for simplicity.

Signed-off-by: Ferry Meng 
Reviewed-by: Gao Xiang 
Reviewed-by: Yue Hu 
Reviewed-by: Chao Yu 
Link: https://lore.kernel.org/r/20231109111822.17944-1-mengferry@linux.alibaba.com
Signed-off-by: Gao Xiang

erofs: convert to new timestamp accessors

2023-10-18T11:26:21+00:00

Convert to using the new inode timestamp accessor functions.

Signed-off-by: Jeff Layton 
Link: https://lore.kernel.org/r/20231004185347.80880-30-jlayton@kernel.org
Signed-off-by: Christian Brauner

Merge tag 'v6.6-vfs.ctime' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

2023-08-28T16:31:32+00:00

Pull vfs timestamp updates from Christian Brauner:
"This adds VFS support for multi-grain timestamps and converts tmpfs,
xfs, ext4, and btrfs to use them. This carries acks from all relevant
filesystems.

The VFS always uses coarse-grained timestamps when updating the ctime
and mtime after a change. This has the benefit of allowing filesystems
to optimize away a lot of metadata updates, down to around 1 per
jiffy, even when a file is under heavy writes.

Unfortunately, this has always been an issue when we're exporting via
NFSv3, which relies on timestamps to validate caches. A lot of changes
can happen in a jiffy, so timestamps aren't sufficient to help the
client decide to invalidate the cache.

Even with NFSv4, a lot of exported filesystems don't properly support
a change attribute and are subject to the same problems with timestamp
granularity. Other applications have similar issues with timestamps
(e.g., backup applications).

If we were to always use fine-grained timestamps, that would improve
the situation, but that becomes rather expensive, as the underlying
filesystem would have to log a lot more metadata updates.

This introduces fine-grained timestamps that are used when they are
actively queried.

This uses the 31st bit of the ctime tv_nsec field to indicate that
something has queried the inode for the mtime or ctime. When this flag
is set, on the next mtime or ctime update, the kernel will fetch a
fine-grained timestamp instead of the usual coarse-grained one.

As POSIX generally mandates that when the mtime changes, the ctime
must also change the kernel always stores normalized ctime values, so
only the first 30 bits of the tv_nsec field are ever used.

Filesytems can opt into this behavior by setting the FS_MGTIME flag in
the fstype. Filesystems that don't set this flag will continue to use
coarse-grained timestamps.

Various preparatory changes, fixes and cleanups are included:

- Fixup all relevant places where POSIX requires updating ctime
together with mtime. This is a wide-range of places and all
maintainers provided necessary Acks.

- Add new accessors for inode->i_ctime directly and change all
callers to rely on them. Plain accesses to inode->i_ctime are now
gone and it is accordingly rename to inode->__i_ctime and commented
as requiring accessors.

- Extend generic_fillattr() to pass in a request mask mirroring in a
sense the statx() uapi. This allows callers to pass in a request
mask to only get a subset of attributes filled in.

- Rework timestamp updates so it's possible to drop the @now
parameter the update_time() inode operation and associated helpers.

- Add inode_update_timestamps() and convert all filesystems to it
removing a bunch of open-coding"

* tag 'v6.6-vfs.ctime' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (107 commits)
btrfs: convert to multigrain timestamps
ext4: switch to multigrain timestamps
xfs: switch to multigrain timestamps
tmpfs: add support for multigrain timestamps
fs: add infrastructure for multigrain timestamps
fs: drop the timespec64 argument from update_time
xfs: have xfs_vn_update_time gets its own timestamp
fat: make fat_update_time get its own timestamp
fat: remove i_version handling from fat_update_time
ubifs: have ubifs_update_time use inode_update_timestamps
btrfs: have it use inode_update_timestamps
fs: drop the timespec64 arg from generic_update_time
fs: pass the request_mask to generic_fillattr
fs: remove silly warning from current_time
gfs2: fix timestamp handling on quota inodes
fs: rename i_ctime field to __i_ctime
selinux: convert to ctime accessor functions
security: convert to ctime accessor functions
apparmor: convert to ctime accessor functions
sunrpc: convert to ctime accessor functions
...

fs: pass the request_mask to generic_fillattr

2023-08-09T06:56:36+00:00

generic_fillattr just fills in the entire stat struct indiscriminately
today, copying data from the inode. There is at least one attribute
(STATX_CHANGE_COOKIE) that can have side effects when it is reported,
and we're looking at adding more with the addition of multigrain
timestamps.

Add a request_mask argument to generic_fillattr and have most callers
just pass in the value that is passed to getattr. Have other callers
(e.g. ksmbd) just pass in STATX_BASIC_STATS. Also move the setting of
STATX_CHANGE_COOKIE into generic_fillattr.

Acked-by: Joseph Qi 
Reviewed-by: Xiubo Li 
Reviewed-by: "Paulo Alcantara (SUSE)" 
Reviewed-by: Jan Kara 
Signed-off-by: Jeff Layton 
Message-Id: <20230807-mgctime-v7-2-d1dec143a704@kernel.org>
Signed-off-by: Christian Brauner

erofs: convert to ctime accessor functions

2023-07-13T08:28:06+00:00

In later patches, we're going to change how the inode's ctime field is
used. Switch to using accessor functions instead of raw accesses of
inode->i_ctime.

Acked-by: Gao Xiang 
Signed-off-by: Jeff Layton 
Message-Id: <20230705190309.579783-37-jlayton@kernel.org>
Signed-off-by: Christian Brauner

erofs: fix fsdax unavailability for chunk-based regular files

2023-07-11T16:50:56+00:00

DAX can be used to share page cache between VMs, reducing guest memory
overhead. And chunk based data format is widely used for VM and
container image. So enable dax support for it, make erofs better used
for VM scenarios.

Fixes: c5aa903a59db ("erofs: support reading chunk-based uncompressed files")
Signed-off-by: Xin Yin 
Reviewed-by: Gao Xiang 
Reviewed-by: Chao Yu 
Link: https://lore.kernel.org/r/20230711062130.7860-1-yinxin.x@bytedance.com
Signed-off-by: Gao Xiang

erofs: sunset erofs_dbg()

2023-04-16T17:15:54+00:00

Such debug messages are rarely used now.  Let's get rid of these,
and revert locally if they are needed for debugging.

Signed-off-by: Gao Xiang 
Reviewed-by: Chao Yu 
Link: https://lore.kernel.org/r/20230414083027.12307-1-hsiangkao@linux.alibaba.com

erofs: get rid of z_erofs_fill_inode()

2023-04-16T17:15:53+00:00

Prior to big pclusters, non-compact compression indexes could have
empty headers.

Let's just avoid the legacy path since it can be handled properly
as a specific compression header with z_erofs_fill_inode_lazy() too.

Tested with erofs-utils exist versions.

Signed-off-by: Gao Xiang 
Reviewed-by: Yue Hu 
Reviewed-by: Chao Yu 
Link: https://lore.kernel.org/r/20230413092241.73829-1-hsiangkao@linux.alibaba.com

erofs: set block size to the on-disk block size

2023-04-16T17:15:45+00:00

Set the block size to that specified in on-disk superblock.

Also remove the hard constraint of PAGE_SIZE block size for the
uncompressed device backend.  This constraint is temporarily remained
for compressed device and fscache backend, as there is more work needed
to handle the condition where the block size is not equal to PAGE_SIZE.

It is worth noting that the on-disk block size is read prior to
erofs_superblock_csum_verify(), as the read block size is needed in the
latter.

Besides, later we are going to make erofs refer to tar data blobs (which
is 512-byte aligned) for OCI containers, where the block size is 512
bytes.  In this case, the 512-byte block size may not be adequate for a
directory to contain enough dirents.  To fix this, we are also going to
introduce directory block size independent on the block size.

Due to we have already supported block size smaller than PAGE_SIZE now,
disable all these images with such separated directory block size until
we supported this feature later.

Signed-off-by: Jingbo Xu 
Reviewed-by: Gao Xiang 
Reviewed-by: Yue Hu 
Reviewed-by: Chao Yu 
Link: https://lore.kernel.org/r/20230313135309.75269-3-jefflexu@linux.alibaba.com
[ Gao Xiang: update documentation. ]
Signed-off-by: Gao Xiang

erofs: avoid hardcoded blocksize for subpage block support

2023-04-16T17:15:44+00:00

As the first step of converting hardcoded blocksize to that specified in
on-disk superblock, convert all call sites of hardcoded blocksize to
sb->s_blocksize except for:

1) use sbi->blkszbits instead of sb->s_blocksize in
erofs_superblock_csum_verify() since sb->s_blocksize has not been
updated with the on-disk blocksize yet when the function is called.

2) use inode->i_blkbits instead of sb->s_blocksize in erofs_bread(),
since the inode operated on may be an anonymous inode in fscache mode.
Currently the anonymous inode is allocated from an anonymous mount
maintained in erofs, while in the near future we may allocate anonymous
inodes from a generic API directly and thus have no access to the
anonymous inode's i_sb.  Thus we keep the block size in i_blkbits for
anonymous inodes in fscache mode.

Be noted that this patch only gets rid of the hardcoded blocksize, in
preparation for actually setting the on-disk block size in the following
patch.  The hard limit of constraining the block size to PAGE_SIZE still
exists until the next patch.

Signed-off-by: Jingbo Xu 
Reviewed-by: Gao Xiang 
Reviewed-by: Yue Hu 
Reviewed-by: Chao Yu 
Link: https://lore.kernel.org/r/20230313135309.75269-2-jefflexu@linux.alibaba.com
[ Gao Xiang: fold a patch to fix incorrect truncated offsets. ]
Link: https://lore.kernel.org/r/20230413035734.15457-1-zhujia.zj@bytedance.com
Signed-off-by: Gao Xiang