2017-02-07 3:33 GMT-08:00 Sachin Prabhu <sprabhu@xxxxxxxxxx>:
> The patch introduces the file_operations helper cifs_copy_file_range().
>
> The vfs helper vfs_copy_file_range() first calls clone_file_range
> which for cifs uses
> SMB2_ioctl(.., FSCTL_DUPLICATE_EXTENTS_TO_FILE, ..)
> to do a server side copy of the file. This ioctl is only supported on
> SMB3 and later versions.
>
> Once this call fails, vfs_copy_file_range() calls copy_file_range()
> corresponding to the cifs filesystem which is introduced by this patch.
> This calls the more widely available
> SMB2_ioctl(.., FSCTL_SRV_COPYCHUNK_WRITE, ..)
>
> The upstream changes in this area was first made by the commit
> 04b38d601239 ("vfs: pull btrfs clone API to vfs layer")
> This commit also introduces the ioctls FICLONE and FICLONERANGE which
> removes the need for separate cifs ioctls to perform server side copies
> and hence can be removed.
>
ioctls FICLONE and FICLONERANGE perform a file clone operation which
for cifs is implemented through FSCTL_DUPLICATE_EXTENTS_TO_FILE for
SMB3 only. ioctl CIFS_IOC_COPYCHUNK_FILE performs a file copy
operation which is implemented through FSCTL_SRV_COPYCHUNK_WRITE. So,
this generic ioctls can't substitute the existing cifs one.
Also there is a copy_file_range() system call that calls
vfs_copy_file_range(). With this patch applied it tries to clone first
and then copy. It means that for SMB3 it will still call
DUPLICATE_EXTENTS_TO_FILE and we end up with two calls issuing
DUPLICATE_EXTENTS_TO_FILE and zero -SRV_COPYCHUNK_WRITE.
Thus I suggest not to remove a separate cifs ioctl that always calls
COPYCHUNK_WRITE for possible scenarios where DUPLICATE_EXTENTS_TO_FILE
is not suitable.
> Signed-off-by: Sachin Prabhu <sprabhu@xxxxxxxxxx>
> ---
> fs/cifs/cifsfs.c | 72 +++++++++++++++++++++++++++++++++++
> fs/cifs/cifsglob.h | 2 +-
> fs/cifs/ioctl.c | 107 -----------------------------------------------------
> fs/cifs/smb2ops.c | 16 +++++---
> 4 files changed, 84 insertions(+), 113 deletions(-)
>
> diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
> index 70f4e65..33bc53d 100644
> --- a/fs/cifs/cifsfs.c
> +++ b/fs/cifs/cifsfs.c
> @@ -972,6 +972,72 @@ static int cifs_clone_file_range(struct file *src_file, loff_t off,
> return rc;
> }
>
> +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)
> +{
> + struct inode *src_inode = file_inode(src_file);
> + struct inode *target_inode = file_inode(dst_file);
> + struct cifsFileInfo *smb_file_src = src_file->private_data;
> + struct cifsFileInfo *smb_file_target = dst_file->private_data;
> + struct cifs_tcon *src_tcon;
> + struct cifs_tcon *target_tcon;
> + unsigned int xid;
> + int rc;
> +
> + xid = get_xid();
> +
> + cifs_dbg(FYI, "copy file 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;
> + 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->clone_range)
> + rc = target_tcon->ses->server->ops->clone_range(xid,
> + smb_file_src, smb_file_target, off, len, destoff);
I think there is a naming confusion here. I suggest to rename
clone_range() callback to copy_range() to reflect its actual logic.
> + 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:
> + 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 +1050,7 @@ 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 +1068,7 @@ 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 +1086,7 @@ 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 +1104,7 @@ 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 +1121,7 @@ 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 +1138,7 @@ 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,
> diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
> index 7ea8a33..ae0c095 100644
> --- a/fs/cifs/cifsglob.h
> +++ b/fs/cifs/cifsglob.h
> @@ -405,7 +405,7 @@ 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 (*clone_range)(const unsigned int, struct cifsFileInfo *src_file,
> + ssize_t (*clone_range)(const unsigned int, struct cifsFileInfo *src_file,
> struct cifsFileInfo *target_file, u64 src_off, u64 len,
> u64 dest_off);
> int (*duplicate_extents)(const unsigned int, struct cifsFileInfo *src,
> diff --git a/fs/cifs/ioctl.c b/fs/cifs/ioctl.c
> index 0015287..14975b7 100644
> --- a/fs/cifs/ioctl.c
> +++ b/fs/cifs/ioctl.c
> @@ -34,110 +34,6 @@
> #include "cifs_ioctl.h"
> #include <linux/btrfs.h>
>
> -static int cifs_file_clone_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 clone 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->clone_range)
> - rc = target_tcon->ses->server->ops->clone_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_clone(unsigned int xid, struct file *dst_file,
> - unsigned long srcfd)
> -{
> - int rc;
> - struct fd src_file;
> - struct inode *src_inode;
> -
> - cifs_dbg(FYI, "ioctl clone range\n");
> - /* the destination must be opened for writing */
> - if (!(dst_file->f_mode & FMODE_WRITE)) {
> - cifs_dbg(FYI, "file target not open for write\n");
> - return -EINVAL;
> - }
> -
> - /* check if target volume is readonly and take reference */
> - rc = mnt_want_write_file(dst_file);
> - if (rc) {
> - cifs_dbg(FYI, "mnt_want_write failed with rc %d\n", rc);
> - return rc;
> - }
> -
> - src_file = fdget(srcfd);
> - if (!src_file.file) {
> - rc = -EBADF;
> - goto out_drop_write;
> - }
> -
> - if (src_file.file->f_op->unlocked_ioctl != cifs_ioctl) {
> - rc = -EBADF;
> - cifs_dbg(VFS, "src file seems to be from a different filesystem type\n");
> - goto out_fput;
> - }
> -
> - src_inode = file_inode(src_file.file);
> - rc = -EINVAL;
> - if (S_ISDIR(src_inode->i_mode))
> - goto out_fput;
> -
> - rc = cifs_file_clone_range(xid, src_file.file, dst_file);
> -
> -out_fput:
> - fdput(src_file);
> -out_drop_write:
> - mnt_drop_write_file(dst_file);
> - return rc;
> -}
> -
> static long smb_mnt_get_fsinfo(unsigned int xid, struct cifs_tcon *tcon,
> void __user *arg)
> {
> @@ -250,9 +146,6 @@ long cifs_ioctl(struct file *filep, unsigned int command, unsigned long arg)
> cifs_dbg(FYI, "set compress flag rc %d\n", rc);
> }
> break;
> - case CIFS_IOC_COPYCHUNK_FILE:
> - rc = cifs_ioctl_clone(xid, filep, arg);
> - break;
> case CIFS_IOC_SET_INTEGRITY:
> if (pSMBFile == NULL)
> break;
> diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c
> index 5d456eb..b7aa0926 100644
> --- a/fs/cifs/smb2ops.c
> +++ b/fs/cifs/smb2ops.c
> @@ -586,7 +586,7 @@ SMB2_request_res_key(const unsigned int xid, struct cifs_tcon *tcon,
> return rc;
> }
>
> -static int
> +static ssize_t
> smb2_clone_range(const unsigned int xid,
> struct cifsFileInfo *srcfile,
> struct cifsFileInfo *trgtfile, u64 src_off,
> @@ -599,6 +599,7 @@ smb2_clone_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);
>
> @@ -662,14 +663,16 @@ smb2_clone_range(const unsigned int xid,
> }
> chunks_copied++;
>
> + bytes_written = le32_to_cpu(retbuf->TotalBytesWritten);
> src_off += le32_to_cpu(retbuf->TotalBytesWritten);
> dest_off += le32_to_cpu(retbuf->TotalBytesWritten);
> - len -= le32_to_cpu(retbuf->TotalBytesWritten);
> + 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;
> @@ -706,7 +709,10 @@ smb2_clone_range(const unsigned int xid,
> cchunk_out:
> kfree(pcchunk);
> kfree(retbuf);
> - return rc;
> + if (rc)
> + return rc;
> + else
> + return total_bytes_written;
> }
>
> static int
> --
> 2.9.3
>
> --
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Other than the comments above the patch looks good.
--
Best regards,
Pavel Shilovsky
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