mirror_zfs/module/os
Rob N ead3eea3e0
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
2023-08-01 11:31:11 -07:00
..
freebsd BRT should return EOPNOTSUPP 2023-07-27 11:32:34 -07:00
linux linux/copy_file_range: properly request a fallback copy on Linux <5.3 2023-08-01 11:31:11 -07:00