Commit 620d8745 authored by Sachin Prabhu's avatar Sachin Prabhu Committed by Steve French
Browse files

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: default avatarSachin Prabhu <sprabhu@redhat.com>
Reviewed-by: default avatarPavel Shilovsky <pshilov@microsoft.com>
CC: Stable  <stable@vger.kernel.org>
Signed-off-by: default avatarSteve French <smfrench@gmail.com>
parent 312bbc59

fs/cifs/cifsfs.c

+87 −0
Original line number Diff line number Diff line
@@ -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,

};

fs/cifs/cifsfs.h

+5 −0
Original line number Diff line number Diff line
@@ -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;

fs/cifs/cifsglob.h

+3 −3
Original line number Diff line number Diff line
@@ -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);

fs/cifs/ioctl.c

+2 −58
Original line number Diff line number Diff line
@@ -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);

fs/cifs/smb2ops.c

+13 −7
Original line number Diff line number Diff line
@@ -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);

	if (rc)

		return rc;

	else

		return total_bytes_written;

}



static int

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