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 inodes are not on the same sb and do not call ->copy_file_range() in case the inodes are not on the same filesystem type. 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@xxxxxxxxxxxxx> Signed-off-by: Dave Chinner <dchinner@xxxxxxxxxx> Signed-off-by: Amir Goldstein <amir73il@xxxxxxxxx> --- fs/ceph/file.c | 4 +++- fs/cifs/cifsfs.c | 2 +- fs/fuse/file.c | 5 ++++- fs/nfs/nfs4file.c | 5 ++++- fs/read_write.c | 20 ++++++++++++++------ 5 files changed, 26 insertions(+), 10 deletions(-) diff --git a/fs/ceph/file.c b/fs/ceph/file.c index 54cfc877a6ef..adf99557c46c 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; @@ -2118,7 +2120,7 @@ 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; diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c index e103b499aaa8..7bde046110ce 100644 --- a/fs/cifs/cifsfs.c +++ b/fs/cifs/cifsfs.c @@ -1152,7 +1152,7 @@ static ssize_t cifs_copy_file_range(struct file *src_file, loff_t off, len, flags); free_xid(xid); - if (rc == -EOPNOTSUPP) + if (rc == -EOPNOTSUPP || rc == -EXDEV) rc = generic_copy_file_range(src_file, off, dst_file, destoff, len, flags); return rc; diff --git a/fs/fuse/file.c b/fs/fuse/file.c index 3531d4a3d9ec..180161f6f0bd 100644 --- a/fs/fuse/file.c +++ b/fs/fuse/file.c @@ -3126,6 +3126,9 @@ static ssize_t __fuse_copy_file_range(struct file *file_in, loff_t pos_in, if (fc->no_copy_file_range) return -EOPNOTSUPP; + if (file_inode(file_in)->i_sb != file_inode(file_out)->i_sb) + return -EXDEV; + inode_lock(inode_out); err = generic_copy_file_range_prep(file_in, file_out); @@ -3186,7 +3189,7 @@ static ssize_t fuse_copy_file_range(struct file *src_file, loff_t src_off, ret = __fuse_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; diff --git a/fs/nfs/nfs4file.c b/fs/nfs/nfs4file.c index 4842f3ab3161..f4157eb1f69d 100644 --- a/fs/nfs/nfs4file.c +++ b/fs/nfs/nfs4file.c @@ -133,6 +133,9 @@ static ssize_t __nfs4_copy_file_range(struct file *file_in, loff_t pos_in, struct file *file_out, loff_t pos_out, size_t count, unsigned int flags) { + /* Only offload copy if superblock is the same */ + if (file_inode(file_in)->i_sb != file_inode(file_out)->i_sb) + return -EXDEV; if (!nfs_server_capable(file_inode(file_out), NFS_CAP_COPY)) return -EOPNOTSUPP; if (file_inode(file_in) == file_inode(file_out)) @@ -148,7 +151,7 @@ static ssize_t nfs4_copy_file_range(struct file *file_in, loff_t pos_in, ret = __nfs4_copy_file_range(file_in, pos_in, file_out, pos_out, count, flags); - if (ret == -EOPNOTSUPP) + if (ret == -EOPNOTSUPP || ret == -EXDEV) ret = generic_copy_file_range(file_in, pos_in, file_out, pos_out, count, flags); return ret; diff --git a/fs/read_write.c b/fs/read_write.c index 4b23a86aacd9..283ec30d2136 100644 --- a/fs/read_write.c +++ b/fs/read_write.c @@ -1640,7 +1640,18 @@ static ssize_t do_copy_file_range(struct file *file_in, loff_t pos_in, struct file *file_out, loff_t pos_out, size_t len, unsigned int flags) { - if (file_out->f_op->copy_file_range) + /* + * Although we now allow filesystems to handle cross sb copy, passing + * an inode of the wrong filesystem type to filesystem operation can + * often result in an attempt to dereference the wrong concrete inode + * struct, so avoid doing that until we really have a good reason. + * The incentive for passing inode from different sb to filesystem is + * NFS cross server copy and for that use case, enforcing same + * filesystem type is acceptable. + */ + if (file_out->f_op->copy_file_range && + file_inode(file_in)->i_sb->s_type == + file_inode(file_out)->i_sb->s_type) return file_out->f_op->copy_file_range(file_in, pos_in, file_out, pos_out, len, flags); @@ -1663,10 +1674,6 @@ ssize_t vfs_copy_file_range(struct file *file_in, loff_t pos_in, if (flags != 0) return -EINVAL; - /* this could be relaxed once a method supports cross-fs copies */ - if (file_inode(file_in)->i_sb != file_inode(file_out)->i_sb) - return -EXDEV; - ret = generic_copy_file_checks(file_in, pos_in, file_out, pos_out, &len, flags); if (unlikely(ret)) @@ -1689,7 +1696,8 @@ ssize_t vfs_copy_file_range(struct file *file_in, loff_t pos_in, * Try cloning first, this is supported by more file systems, and * more efficient if both clone and copy are supported (e.g. NFS). */ - if (file_in->f_op->remap_file_range) { + if (file_in->f_op->remap_file_range && + file_inode(file_in)->i_sb == file_inode(file_out)->i_sb) { loff_t cloned; cloned = file_in->f_op->remap_file_range(file_in, pos_in, -- 2.17.1