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>
This commit is contained in:
Sachin Prabhu 2017-02-10 16:03:51 +05:30 committed by Steve French
parent 312bbc5946
commit 620d8745b3
5 changed files with 110 additions and 68 deletions

View File

@ -972,6 +972,86 @@ out:
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,
};

View File

@ -139,6 +139,11 @@ extern ssize_t cifs_listxattr(struct dentry *, char *, size_t);
# define cifs_listxattr NULL
#endif
extern 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);
extern long cifs_ioctl(struct file *filep, unsigned int cmd, unsigned long arg);
#ifdef CONFIG_CIFS_NFSD_EXPORT
extern const struct export_operations cifs_export_ops;

View File

@ -408,10 +408,10 @@ struct smb_version_operations {
char * (*create_lease_buf)(u8 *, u8);
/* parse lease context buffer and return oplock/epoch info */
__u8 (*parse_lease_buf)(void *, unsigned int *);
int (*copychunk_range)(const unsigned int,
ssize_t (*copychunk_range)(const unsigned int,
struct cifsFileInfo *src_file,
struct cifsFileInfo *target_file, u64 src_off, u64 len,
u64 dest_off);
struct cifsFileInfo *target_file,
u64 src_off, u64 len, u64 dest_off);
int (*duplicate_extents)(const unsigned int, struct cifsFileInfo *src,
struct cifsFileInfo *target_file, u64 src_off, u64 len,
u64 dest_off);

View File

@ -34,63 +34,6 @@
#include "cifs_ioctl.h"
#include <linux/btrfs.h>
static int cifs_file_copychunk_range(unsigned int xid, struct file *src_file,
struct file *dst_file)
{
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;
int rc;
cifs_dbg(FYI, "ioctl copychunk range\n");
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, 0, src_inode->i_size, 0);
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 long cifs_ioctl_copychunk(unsigned int xid, struct file *dst_file,
unsigned long srcfd)
{
@ -129,7 +72,8 @@ static long cifs_ioctl_copychunk(unsigned int xid, struct file *dst_file,
if (S_ISDIR(src_inode->i_mode))
goto out_fput;
rc = cifs_file_copychunk_range(xid, src_file.file, dst_file);
rc = cifs_file_copychunk_range(xid, src_file.file, 0, dst_file, 0,
src_inode->i_size, 0);
out_fput:
fdput(src_file);

View File

@ -592,7 +592,7 @@ req_res_key_exit:
return rc;
}
static int
static ssize_t
smb2_copychunk_range(const unsigned int xid,
struct cifsFileInfo *srcfile,
struct cifsFileInfo *trgtfile, u64 src_off,
@ -605,6 +605,7 @@ smb2_copychunk_range(const unsigned int xid,
struct cifs_tcon *tcon;
int chunks_copied = 0;
bool chunk_sizes_updated = false;
ssize_t bytes_written, total_bytes_written = 0;
pcchunk = kmalloc(sizeof(struct copychunk_ioctl), GFP_KERNEL);
@ -669,14 +670,16 @@ smb2_copychunk_range(const unsigned int xid,
}
chunks_copied++;
src_off += le32_to_cpu(retbuf->TotalBytesWritten);
dest_off += le32_to_cpu(retbuf->TotalBytesWritten);
len -= le32_to_cpu(retbuf->TotalBytesWritten);
bytes_written = le32_to_cpu(retbuf->TotalBytesWritten);
src_off += bytes_written;
dest_off += bytes_written;
len -= bytes_written;
total_bytes_written += bytes_written;
cifs_dbg(FYI, "Chunks %d PartialChunk %d Total %d\n",
cifs_dbg(FYI, "Chunks %d PartialChunk %d Total %zu\n",
le32_to_cpu(retbuf->ChunksWritten),
le32_to_cpu(retbuf->ChunkBytesWritten),
le32_to_cpu(retbuf->TotalBytesWritten));
bytes_written);
} else if (rc == -EINVAL) {
if (ret_data_len != sizeof(struct copychunk_ioctl_rsp))
goto cchunk_out;
@ -713,7 +716,10 @@ smb2_copychunk_range(const unsigned int xid,
cchunk_out:
kfree(pcchunk);
kfree(retbuf);
return rc;
if (rc)
return rc;
else
return total_bytes_written;
}
static int