Now that a few file systems are adding clone functionality, namingly
btrfs, CIFS, NFS (in another series) and XFS
(ttp://oss.sgi.com/archives/xfs/2015-06/msg00407.html), it makes sense
to pull the ioctl to common code.

Signed-off-by: Peng Tao <tao.p...@primarydata.com>
---
 fs/ioctl.c              | 40 ++++++++++++++++++++++++++++++++++++++++
 include/uapi/linux/fs.h |  9 +++++++++
 2 files changed, 49 insertions(+)

diff --git a/fs/ioctl.c b/fs/ioctl.c
index 5d01d26..9a78426 100644
--- a/fs/ioctl.c
+++ b/fs/ioctl.c
@@ -215,6 +215,40 @@ static int ioctl_fiemap(struct file *filp, unsigned long 
arg)
        return error;
 }
 
+static long ioctl_file_clone(struct file *dst_file, unsigned long srcfd,
+                            u64 off, u64 olen, u64 destoff)
+{
+       struct fd src_file = fdget(srcfd);
+       struct inode *src_inode;
+       int ret;
+
+       if (!src_file.file)
+               return -EBADF;
+       /* olen == 0 means src off to eof */
+       if (olen == 0) {
+               src_inode = file_inode(src_file.file);
+               olen = i_size_read(src_inode) - off;
+       }
+       ret = vfs_copy_file_range(src_file.file, off, dst_file,
+                                 destoff, olen, COPY_FILE_CLONE_ONLY);
+       /* vfs_copy_file_range returns bytes copied */
+       if (ret > 0)
+               ret = 0;
+
+       fdput(src_file);
+       return ret;
+}
+
+static long ioctl_file_clone_range(struct file *file, void __user *argp)
+{
+       struct file_clone_range args;
+
+       if (copy_from_user(&args, argp, sizeof(args)))
+               return -EFAULT;
+       return ioctl_file_clone(file, args.src_fd, args.src_offset,
+                               args.src_length, args.dest_offset);
+}
+
 #ifdef CONFIG_BLOCK
 
 static inline sector_t logical_to_blk(struct inode *inode, loff_t offset)
@@ -600,6 +634,12 @@ int do_vfs_ioctl(struct file *filp, unsigned int fd, 
unsigned int cmd,
        case FIGETBSZ:
                return put_user(inode->i_sb->s_blocksize, argp);
 
+       case FICLONE:
+               return ioctl_file_clone(filp, arg, 0, 0, 0);
+
+       case FICLONERANGE:
+               return ioctl_file_clone_range(filp, argp);
+
        default:
                if (S_ISREG(inode->i_mode))
                        error = file_ioctl(filp, cmd, arg);
diff --git a/include/uapi/linux/fs.h b/include/uapi/linux/fs.h
index 9b964a5..ac7f1c5 100644
--- a/include/uapi/linux/fs.h
+++ b/include/uapi/linux/fs.h
@@ -39,6 +39,13 @@
 #define RENAME_EXCHANGE                (1 << 1)        /* Exchange source and 
dest */
 #define RENAME_WHITEOUT                (1 << 2)        /* Whiteout source */
 
+struct file_clone_range {
+       __s64 src_fd;
+       __u64 src_offset;
+       __u64 src_length;
+       __u64 dest_offset;
+};
+
 struct fstrim_range {
        __u64 start;
        __u64 len;
@@ -159,6 +166,8 @@ struct inodes_stat_t {
 #define FIFREEZE       _IOWR('X', 119, int)    /* Freeze */
 #define FITHAW         _IOWR('X', 120, int)    /* Thaw */
 #define FITRIM         _IOWR('X', 121, struct fstrim_range)    /* Trim */
+#define FICLONE                _IOW(0x94, 9, int)      /* Clone */
+#define FICLONERANGE   _IOW(0x94, 13, struct file_clone_range) /* Clone range 
*/
 
 #define        FS_IOC_GETFLAGS                 _IOR('f', 1, long)
 #define        FS_IOC_SETFLAGS                 _IOW('f', 2, long)
-- 
1.8.3.1

--
To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to