vfs: allow copy_file_range to copy across devices
We want to enable cross-filesystem copy_file_range functionality
where possible, so push the "same superblock only" checks down to
the individual filesystem callouts so they can make their own
decisions about cross-superblock copy offload and fallack to
generic_copy_file_range() for cross-superblock copy.
[Amir] We do not call ->remap_file_range() in case the files are not
on the same sb and do not call ->copy_file_range() in case the files
do not belong to the same filesystem driver.
This changes behavior of the copy_file_range(2) syscall, which will
now allow cross filesystem in-kernel copy. CIFS already supports
cross-superblock copy, between two shares to the same server. This
functionality will now be available via the copy_file_range(2) syscall.
Cc: Steve French <stfrench@microsoft.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff --git a/fs/ceph/file.c b/fs/ceph/file.c
index 31d4505..c5517ff 100644
--- a/fs/ceph/file.c
+++ b/fs/ceph/file.c
@@ -1909,6 +1909,8 @@ static ssize_t __ceph_copy_file_range(struct file *src_file, loff_t src_off,
if (src_inode == dst_inode)
return -EINVAL;
+ if (src_inode->i_sb != dst_inode->i_sb)
+ return -EXDEV;
if (ceph_snap(dst_inode) != CEPH_NOSNAP)
return -EROFS;
@@ -2109,7 +2111,7 @@ static ssize_t ceph_copy_file_range(struct file *src_file, loff_t src_off,
ret = __ceph_copy_file_range(src_file, src_off, dst_file, dst_off,
len, flags);
- if (ret == -EOPNOTSUPP)
+ if (ret == -EOPNOTSUPP || ret == -EXDEV)
ret = generic_copy_file_range(src_file, src_off, dst_file,
dst_off, len, flags);
return ret;