- /* Don't reflink dirs, pipes, sockets... */
- if (S_ISDIR(inode_in->i_mode) || S_ISDIR(inode_out->i_mode))
- return -EISDIR;
- if (!S_ISREG(inode_in->i_mode) || !S_ISREG(inode_out->i_mode))
- return -EINVAL;
-
- /* Zero length dedupe exits immediately; reflink goes to EOF. */
- if (*len == 0) {
- loff_t isize = i_size_read(inode_in);
-
- if ((remap_flags & REMAP_FILE_DEDUP) || pos_in == isize)
- return 0;
- if (pos_in > isize)
- return -EINVAL;
- *len = isize - pos_in;
- if (*len == 0)
- return 0;
- }
-
- /* Check that we don't violate system file offset limits. */
- ret = generic_remap_checks(file_in, pos_in, file_out, pos_out, len,
- remap_flags);
- if (ret)
- return ret;
-
- /* Wait for the completion of any pending IOs on both files */
- inode_dio_wait(inode_in);
- if (!same_inode)
- inode_dio_wait(inode_out);
-
- ret = filemap_write_and_wait_range(inode_in->i_mapping,
- pos_in, pos_in + *len - 1);
- if (ret)
- return ret;
-
- ret = filemap_write_and_wait_range(inode_out->i_mapping,
- pos_out, pos_out + *len - 1);
- if (ret)
- return ret;
-
- /*
- * Check that the extents are the same.
- */
- if (remap_flags & REMAP_FILE_DEDUP) {
- bool is_same = false;
-
- ret = vfs_dedupe_file_range_compare(inode_in, pos_in,
- inode_out, pos_out, *len, &is_same);
- if (ret)
- return ret;
- if (!is_same)
- return -EBADE;
- }
-
- ret = generic_remap_check_len(inode_in, inode_out, pos_out, len,
- remap_flags);
- if (ret)
- return ret;
-
- /* If can't alter the file contents, we're done. */
- if (!(remap_flags & REMAP_FILE_DEDUP))
- ret = file_modified(file_out);
-
- return ret;
-}
-EXPORT_SYMBOL(generic_remap_file_range_prep);
-
-loff_t do_clone_file_range(struct file *file_in, loff_t pos_in,
- struct file *file_out, loff_t pos_out,
- loff_t len, unsigned int remap_flags)
-{
- loff_t ret;
-
- WARN_ON_ONCE(remap_flags & REMAP_FILE_DEDUP);
-
- /*
- * FICLONE/FICLONERANGE ioctls enforce that src and dest files are on
- * the same mount. Practically, they only need to be on the same file
- * system.
- */
- if (file_inode(file_in)->i_sb != file_inode(file_out)->i_sb)
- return -EXDEV;
-
- ret = generic_file_rw_checks(file_in, file_out);
- if (ret < 0)
- return ret;
-
- if (!file_in->f_op->remap_file_range)
- return -EOPNOTSUPP;
-
- ret = remap_verify_area(file_in, pos_in, len, false);
- if (ret)
- return ret;
-
- ret = remap_verify_area(file_out, pos_out, len, true);
- if (ret)
- return ret;
-
- ret = file_in->f_op->remap_file_range(file_in, pos_in,
- file_out, pos_out, len, remap_flags);
- if (ret < 0)
- return ret;
-
- fsnotify_access(file_in);
- fsnotify_modify(file_out);
- return ret;
-}
-EXPORT_SYMBOL(do_clone_file_range);
-
-loff_t vfs_clone_file_range(struct file *file_in, loff_t pos_in,
- struct file *file_out, loff_t pos_out,
- loff_t len, unsigned int remap_flags)
-{
- loff_t ret;
-
- file_start_write(file_out);
- ret = do_clone_file_range(file_in, pos_in, file_out, pos_out, len,
- remap_flags);
- file_end_write(file_out);
-
- return ret;
-}
-EXPORT_SYMBOL(vfs_clone_file_range);
-
-/* Check whether we are allowed to dedupe the destination file */
-static bool allow_file_dedupe(struct file *file)
-{
- if (capable(CAP_SYS_ADMIN))
- return true;
- if (file->f_mode & FMODE_WRITE)
- return true;
- if (uid_eq(current_fsuid(), file_inode(file)->i_uid))
- return true;
- if (!inode_permission(file_inode(file), MAY_WRITE))
- return true;
- return false;
-}