kernel/linux.git/include/linux/fs.h, branch linux-4.20.y

Merge tag 'xfs-4.20-merge-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux

2018-11-02T16:33:08+00:00

Pull vfs dedup fixes from Dave Chinner: "This reworks the vfs data cloning infrastructure. We discovered many issues with these interfaces late in the 4.19 cycle - the worst of them (data corruption, setuid stripping) were fixed for XFS in 4.19-rc8, but a larger rework of the infrastructure fixing all the problems was needed. That rework is the contents of this pull request. Rework the vfs_clone_file_range and vfs_dedupe_file_range infrastructure to use a common .remap_file_range method and supply generic bounds and sanity checking functions that are shared with the data write path. The current VFS infrastructure has problems with rlimit, LFS file sizes, file time stamps, maximum filesystem file sizes, stripping setuid bits, etc and so they are addressed in these commits. We also introduce the ability for the ->remap_file_range methods to return short clones so that clones for vfs_copy_file_range() don't get rejected if the entire range can't be cloned. It also allows filesystems to sliently skip deduplication of partial EOF blocks if they are not capable of doing so without requiring errors to be thrown to userspace. Existing filesystems are converted to user the new remap_file_range method, and both XFS and ocfs2 are modified to make use of the new generic checking infrastructure" * tag 'xfs-4.20-merge-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: (28 commits) xfs: remove [cm]time update from reflink calls xfs: remove xfs_reflink_remap_range xfs: remove redundant remap partial EOF block checks xfs: support returning partial reflink results xfs: clean up xfs_reflink_remap_blocks call site xfs: fix pagecache truncation prior to reflink ocfs2: remove ocfs2_reflink_remap_range ocfs2: support partial clone range and dedupe range ocfs2: fix pagecache truncation prior to reflink ocfs2: truncate page cache for clone destination file before remapping vfs: clean up generic_remap_file_range_prep return value vfs: hide file range comparison function vfs: enable remap callers that can handle short operations vfs: plumb remap flags through the vfs dedupe functions vfs: plumb remap flags through the vfs clone functions vfs: make remap_file_range functions take and return bytes completed vfs: remap helper should update destination inode metadata vfs: pass remap flags to generic_remap_checks vfs: pass remap flags to generic_remap_file_range_prep vfs: combine the clone and dedupe into a single remap_file_range ...

vfs: hide file range comparison function

2018-10-29T23:42:17+00:00

There are no callers of vfs_dedupe_file_range_compare, so we might as well make it a static helper and remove the export. Signed-off-by: Darrick J. Wong Reviewed-by: Amir Goldstein Reviewed-by: Christoph Hellwig Signed-off-by: Dave Chinner

vfs: enable remap callers that can handle short operations

2018-10-29T23:42:10+00:00

Plumb in a remap flag that enables the filesystem remap handler to shorten remapping requests for callers that can handle it. Now copy_file_range can report partial success (in case we run up against alignment problems, resource limits, etc.). We also enable CAN_SHORTEN for fideduperange to maintain existing userspace-visible behavior where xfs/btrfs shorten the dedupe range to avoid stale post-eof data exposure. Signed-off-by: Darrick J. Wong Reviewed-by: Amir Goldstein Signed-off-by: Dave Chinner

vfs: plumb remap flags through the vfs dedupe functions

2018-10-29T23:42:03+00:00

Plumb a remap_flags argument through the vfs_dedupe_file_range_one functions so that dedupe can take advantage of it. Signed-off-by: Darrick J. Wong Reviewed-by: Amir Goldstein Signed-off-by: Dave Chinner

vfs: plumb remap flags through the vfs clone functions

2018-10-29T23:41:56+00:00

Plumb a remap_flags argument through the {do,vfs}_clone_file_range functions so that clone can take advantage of it. Signed-off-by: Darrick J. Wong Reviewed-by: Amir Goldstein Signed-off-by: Dave Chinner

vfs: make remap_file_range functions take and return bytes completed

2018-10-29T23:41:49+00:00

Change the remap_file_range functions to take a number of bytes to operate upon and return the number of bytes they operated on. This is a requirement for allowing fs implementations to return short clone/dedupe results to the user, which will enable us to obey resource limits in a graceful manner. A subsequent patch will enable copy_file_range to signal to the ->clone_file_range implementation that it can handle a short length, which will be returned in the function's return value. For now the short return is not implemented anywhere so the behavior won't change -- either copy_file_range manages to clone the entire range or it tries an alternative. Neither clone ioctl can take advantage of this, alas. Signed-off-by: Darrick J. Wong Reviewed-by: Amir Goldstein Signed-off-by: Dave Chinner

vfs: pass remap flags to generic_remap_checks

2018-10-29T23:41:34+00:00

Pass the same remap flags to generic_remap_checks for consistency. Signed-off-by: Darrick J. Wong Reviewed-by: Amir Goldstein Reviewed-by: Christoph Hellwig Signed-off-by: Dave Chinner

vfs: pass remap flags to generic_remap_file_range_prep

2018-10-29T23:41:28+00:00

Plumb the remap flags through the filesystem from the vfs function dispatcher all the way to the prep function to prepare for behavior changes in subsequent patches. Signed-off-by: Darrick J. Wong Reviewed-by: Amir Goldstein Reviewed-by: Christoph Hellwig Signed-off-by: Dave Chinner

vfs: combine the clone and dedupe into a single remap_file_range

2018-10-29T23:41:21+00:00

Combine the clone_file_range and dedupe_file_range operations into a single remap_file_range file operation dispatch since they're fundamentally the same operation. The differences between the two can be made in the prep functions. Signed-off-by: Darrick J. Wong Reviewed-by: Amir Goldstein Reviewed-by: Christoph Hellwig Signed-off-by: Dave Chinner

vfs: rename vfs_clone_file_prep to be more descriptive

2018-10-29T23:41:08+00:00

The vfs_clone_file_prep is a generic function to be called by filesystem implementations only. Rename the prefix to generic_ and make it more clear that it applies to remap operations, not just clones. Signed-off-by: Darrick J. Wong Reviewed-by: Amir Goldstein Signed-off-by: Dave Chinner