Commit Graph

4 Commits

Author SHA1 Message Date
Rob N
c47f0f4417 linux/copy_file_range: properly request a fallback copy on Linux <5.3
Before Linux 5.3, the filesystem's copy_file_range handler had to signal
back to the kernel that we can't fulfill the request and it should
fallback to a content copy. This is done by returning -EOPNOTSUPP.

This commit converts the EXDEV return from zfs_clone_range to
EOPNOTSUPP, to force the kernel to fallback for all the valid reasons it
might be unable to clone. Without it the copy_file_range() syscall will
return EXDEV to userspace, breaking its semantics.

Add test for copy_file_range fallbacks.  copy_file_range should always
fallback to a content copy whenever ZFS can't service the request with
cloning.

Reviewed-by: Brian Atkinson <batkinson@lanl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Kay Pedersen <mail@mkwg.de>
Signed-off-by: Rob Norris <robn@despairlabs.com>
Closes #15131
2023-08-02 08:52:40 -07:00
Rob Norris
2768dc04cc linux: implement filesystem-side copy/clone functions for EL7
Redhat have backported copy_file_range and clone_file_range to the EL7
kernel using an "extended file operations" wrapper structure. This
connects all that up to let cloning work there too.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Kay Pedersen <mail@mkwg.de>
Signed-off-by: Rob Norris <rob.norris@klarasystems.com>
Sponsored-By: OpenDrives Inc.
Sponsored-By: Klara Inc.
Closes #15050
2023-07-26 08:46:58 -07:00
Rob Norris
3366ceaf3a linux: implement filesystem-side clone ioctls
Prior to Linux 4.5, the FICLONE etc ioctls were specific to BTRFS, and
were implemented as regular filesystem-specific ioctls. This implements
those ioctls directly in OpenZFS, allowing cloning to work on older
kernels.

There's no need to gate these behind version checks; on later kernels
Linux will simply never deliver these ioctls, instead calling the
approprate VFS op.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Kay Pedersen <mail@mkwg.de>
Signed-off-by: Rob Norris <rob.norris@klarasystems.com>
Sponsored-By: OpenDrives Inc.
Sponsored-By: Klara Inc.
Closes #15050
2023-07-26 08:46:58 -07:00
Rob Norris
5d12545da8 linux: implement filesystem-side copy/clone functions
This implements the Linux VFS ops required to service the file
copy/clone APIs:

  .copy_file_range    (4.5+)
  .clone_file_range   (4.5-4.19)
  .dedupe_file_range  (4.5-4.19)
  .remap_file_range   (4.20+)

Note that dedupe_file_range() and remap_file_range(REMAP_FILE_DEDUP) are
hooked up here, but are not implemented yet.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Kay Pedersen <mail@mkwg.de>
Signed-off-by: Rob Norris <rob.norris@klarasystems.com>
Sponsored-By: OpenDrives Inc.
Sponsored-By: Klara Inc.
Closes #15050
2023-07-26 08:46:58 -07:00