Introduce cifs_copy_file_range()
The earlier changes to copy range for cifs unintentionally disabled the more
common form of server side copy.
The patch introduces the file_operations helper cifs_copy_file_range()
which is used by the syscall copy_file_range. The new file operations
helper allows us to perform server side copies for SMB2.0 and 2.1
servers as well as SMB 3.0+ servers which do not support the ioctl
FSCTL_DUPLICATE_EXTENTS_TO_FILE.
The new helper uses the ioctl FSCTL_SRV_COPYCHUNK_WRITE to perform
server side copies. The helper is called by vfs_copy_file_range() only
once an attempt to clone the file using the ioctl
FSCTL_DUPLICATE_EXTENTS_TO_FILE has failed.
Signed-off-by: Sachin Prabhu <sprabhu@redhat.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Steve French <smfrench@gmail.com>
diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
index 15e1db8..dd3f5fa 100644
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -972,6 +972,86 @@ static int cifs_clone_file_range(struct file *src_file, loff_t off,
return rc;
}
+ssize_t cifs_file_copychunk_range(unsigned int xid,
+ struct file *src_file, loff_t off,
+ struct file *dst_file, loff_t destoff,
+ size_t len, unsigned int flags)
+{
+ struct inode *src_inode = file_inode(src_file);
+ struct inode *target_inode = file_inode(dst_file);
+ struct cifsFileInfo *smb_file_src;
+ struct cifsFileInfo *smb_file_target;
+ struct cifs_tcon *src_tcon;
+ struct cifs_tcon *target_tcon;
+ ssize_t rc;
+
+ cifs_dbg(FYI, "copychunk range\n");
+
+ if (src_inode == target_inode) {
+ rc = -EINVAL;
+ goto out;
+ }
+
+ if (!src_file->private_data || !dst_file->private_data) {
+ rc = -EBADF;
+ cifs_dbg(VFS, "missing cifsFileInfo on copy range src file\n");
+ goto out;
+ }
+
+ rc = -EXDEV;
+ smb_file_target = dst_file->private_data;
+ smb_file_src = src_file->private_data;
+ src_tcon = tlink_tcon(smb_file_src->tlink);
+ target_tcon = tlink_tcon(smb_file_target->tlink);
+
+ if (src_tcon->ses != target_tcon->ses) {
+ cifs_dbg(VFS, "source and target of copy not on same server\n");
+ goto out;
+ }
+
+ /*
+ * Note: cifs case is easier than btrfs since server responsible for
+ * checks for proper open modes and file type and if it wants
+ * server could even support copy of range where source = target
+ */
+ lock_two_nondirectories(target_inode, src_inode);
+
+ cifs_dbg(FYI, "about to flush pages\n");
+ /* should we flush first and last page first */
+ truncate_inode_pages(&target_inode->i_data, 0);
+
+ if (target_tcon->ses->server->ops->copychunk_range)
+ rc = target_tcon->ses->server->ops->copychunk_range(xid,
+ smb_file_src, smb_file_target, off, len, destoff);
+ else
+ rc = -EOPNOTSUPP;
+
+ /* force revalidate of size and timestamps of target file now
+ * that target is updated on the server
+ */
+ CIFS_I(target_inode)->time = 0;
+ /* although unlocking in the reverse order from locking is not
+ * strictly necessary here it is a little cleaner to be consistent
+ */
+ unlock_two_nondirectories(src_inode, target_inode);
+
+out:
+ return rc;
+}
+
+static ssize_t cifs_copy_file_range(struct file *src_file, loff_t off,
+ struct file *dst_file, loff_t destoff,
+ size_t len, unsigned int flags)
+{
+ unsigned int xid = get_xid();
+ ssize_t rc;
+
+ rc = cifs_file_copychunk_range(xid, src_file, off, dst_file, destoff,
+ len, flags);
+ free_xid(xid);
+ return rc;
+}
+
const struct file_operations cifs_file_ops = {
.read_iter = cifs_loose_read_iter,
.write_iter = cifs_file_write_iter,
@@ -984,6 +1064,7 @@ const struct file_operations cifs_file_ops = {
.splice_read = generic_file_splice_read,
.llseek = cifs_llseek,
.unlocked_ioctl = cifs_ioctl,
+ .copy_file_range = cifs_copy_file_range,
.clone_file_range = cifs_clone_file_range,
.setlease = cifs_setlease,
.fallocate = cifs_fallocate,
@@ -1001,6 +1082,7 @@ const struct file_operations cifs_file_strict_ops = {
.splice_read = generic_file_splice_read,
.llseek = cifs_llseek,
.unlocked_ioctl = cifs_ioctl,
+ .copy_file_range = cifs_copy_file_range,
.clone_file_range = cifs_clone_file_range,
.setlease = cifs_setlease,
.fallocate = cifs_fallocate,
@@ -1018,6 +1100,7 @@ const struct file_operations cifs_file_direct_ops = {
.mmap = cifs_file_mmap,
.splice_read = generic_file_splice_read,
.unlocked_ioctl = cifs_ioctl,
+ .copy_file_range = cifs_copy_file_range,
.clone_file_range = cifs_clone_file_range,
.llseek = cifs_llseek,
.setlease = cifs_setlease,
@@ -1035,6 +1118,7 @@ const struct file_operations cifs_file_nobrl_ops = {
.splice_read = generic_file_splice_read,
.llseek = cifs_llseek,
.unlocked_ioctl = cifs_ioctl,
+ .copy_file_range = cifs_copy_file_range,
.clone_file_range = cifs_clone_file_range,
.setlease = cifs_setlease,
.fallocate = cifs_fallocate,
@@ -1051,6 +1135,7 @@ const struct file_operations cifs_file_strict_nobrl_ops = {
.splice_read = generic_file_splice_read,
.llseek = cifs_llseek,
.unlocked_ioctl = cifs_ioctl,
+ .copy_file_range = cifs_copy_file_range,
.clone_file_range = cifs_clone_file_range,
.setlease = cifs_setlease,
.fallocate = cifs_fallocate,
@@ -1067,6 +1152,7 @@ const struct file_operations cifs_file_direct_nobrl_ops = {
.mmap = cifs_file_mmap,
.splice_read = generic_file_splice_read,
.unlocked_ioctl = cifs_ioctl,
+ .copy_file_range = cifs_copy_file_range,
.clone_file_range = cifs_clone_file_range,
.llseek = cifs_llseek,
.setlease = cifs_setlease,
@@ -1078,6 +1164,7 @@ const struct file_operations cifs_dir_ops = {
.release = cifs_closedir,
.read = generic_read_dir,
.unlocked_ioctl = cifs_ioctl,
+ .copy_file_range = cifs_copy_file_range,
.clone_file_range = cifs_clone_file_range,
.llseek = generic_file_llseek,
};