Maybe should update David Disseldorp's test tool as well so user space
code to experiment with this easily
On Mon, Sep 3, 2018 at 1:57 AM Ronnie Sahlberg <lsahlber@xxxxxxxxxx> wrote:
>
> Add a new ioctl for COPYCHUNK that copies a region. The existing
> COPYCHUNK can only be used to copy a whole file.
>
> Signed-off-by: Ronnie Sahlberg <lsahlber@xxxxxxxxxx>
> ---
> fs/cifs/cifs_ioctl.h | 8 ++++++++
> fs/cifs/ioctl.c | 53 ++++++++++++++++++++++++++++++++++++++++++++++------
> 2 files changed, 55 insertions(+), 6 deletions(-)
>
> diff --git a/fs/cifs/cifs_ioctl.h b/fs/cifs/cifs_ioctl.h
> index 57ff0756e30c..b40b9b608dde 100644
> --- a/fs/cifs/cifs_ioctl.h
> +++ b/fs/cifs/cifs_ioctl.h
> @@ -43,8 +43,16 @@ struct smb_snapshot_array {
> /* snapshots[]; */
> } __packed;
>
> +struct smb_srv_copychunk {
> + __u32 src_fd;
> + __u32 length;
> + __u64 src_offset;
> + __u64 dst_offset;
> +} __packed;
> +
> #define CIFS_IOCTL_MAGIC 0xCF
> #define CIFS_IOC_COPYCHUNK_FILE _IOW(CIFS_IOCTL_MAGIC, 3, int)
> #define CIFS_IOC_SET_INTEGRITY _IO(CIFS_IOCTL_MAGIC, 4)
> #define CIFS_IOC_GET_MNT_INFO _IOR(CIFS_IOCTL_MAGIC, 5, struct smb_mnt_fs_info)
> #define CIFS_ENUMERATE_SNAPSHOTS _IOR(CIFS_IOCTL_MAGIC, 6, struct smb_snapshot_array)
> +#define CIFS_IOC_COPYCHUNK _IOW(CIFS_IOCTL_MAGIC, 7, struct smb_srv_copychunk)
> diff --git a/fs/cifs/ioctl.c b/fs/cifs/ioctl.c
> index 54f32f9143a9..91f87ea01be0 100644
> --- a/fs/cifs/ioctl.c
> +++ b/fs/cifs/ioctl.c
> @@ -34,14 +34,13 @@
> #include "cifs_ioctl.h"
> #include <linux/btrfs.h>
>
> -static long cifs_ioctl_copychunk(unsigned int xid, struct file *dst_file,
> - unsigned long srcfd)
> +static long _cifs_ioctl_copychunk(unsigned int xid, struct file *dst_file,
> + struct smb_srv_copychunk *cc)
> {
> int rc;
> struct fd src_file;
> struct inode *src_inode;
>
> - cifs_dbg(FYI, "ioctl copychunk 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");
> @@ -55,7 +54,7 @@ static long cifs_ioctl_copychunk(unsigned int xid, struct file *dst_file,
> return rc;
> }
>
> - src_file = fdget(srcfd);
> + src_file = fdget(cc->src_fd);
> if (!src_file.file) {
> rc = -EBADF;
> goto out_drop_write;
> @@ -72,8 +71,9 @@ 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, 0, dst_file, 0,
> - src_inode->i_size, 0);
> + rc = cifs_file_copychunk_range(xid, src_file.file, cc->src_offset,
> + dst_file, cc->dst_offset,
> + cc->length, 0);
> if (rc > 0)
> rc = 0;
> out_fput:
> @@ -83,6 +83,44 @@ static long cifs_ioctl_copychunk(unsigned int xid, struct file *dst_file,
> return rc;
> }
>
> +static long cifs_ioctl_copychunk(unsigned int xid, struct file *dst_file,
> + unsigned long p)
> +{
> + void __user *arg = (void __user *)p;
> + struct smb_srv_copychunk cc;
> +
> + cifs_dbg(FYI, "ioctl copychunk range\n");
> +
> + if (copy_from_user(&cc, arg, sizeof(cc)))
> + return -EFAULT;
> +
> + return _cifs_ioctl_copychunk(xid, dst_file, &cc);
> +}
> +
> +static long cifs_ioctl_copychunk_file(unsigned int xid, struct file *dst_file,
> + unsigned long srcfd)
> +{
> + struct smb_srv_copychunk cc;
> + struct fd src_file;
> + struct inode *src_inode;
> +
> + cifs_dbg(FYI, "ioctl copychunk file\n");
> +
> + src_file = fdget(srcfd);
> + if (!src_file.file) {
> + mnt_drop_write_file(dst_file);
> + return -EBADF;
> + }
> + src_inode = file_inode(src_file.file);
> +
> + memset(&cc, 0, sizeof(struct smb_srv_copychunk));
> + cc.src_fd = srcfd;
> + cc.length = src_inode->i_size;
> + fdput(src_file);
> +
> + return _cifs_ioctl_copychunk(xid, dst_file, &cc);
> +}
> +
> static long smb_mnt_get_fsinfo(unsigned int xid, struct cifs_tcon *tcon,
> void __user *arg)
> {
> @@ -194,6 +232,9 @@ long cifs_ioctl(struct file *filep, unsigned int command, unsigned long arg)
> }
> break;
> case CIFS_IOC_COPYCHUNK_FILE:
> + rc = cifs_ioctl_copychunk_file(xid, filep, arg);
> + break;
> + case CIFS_IOC_COPYCHUNK:
> rc = cifs_ioctl_copychunk(xid, filep, arg);
> break;
> case CIFS_IOC_SET_INTEGRITY:
> --
> 2.13.3
>
--
Thanks,
Steve
