len, remap_flags);
}
+static bool file_sync_write(const struct file *file)
+{
+ if (file->f_flags & (__O_SYNC | O_DSYNC))
+ return true;
+ if (IS_SYNC(file_inode(file)))
+ return true;
+
+ return false;
+}
+
loff_t btrfs_remap_file_range(struct file *src_file, loff_t off,
struct file *dst_file, loff_t destoff, loff_t len,
unsigned int remap_flags)
unlock_two_nondirectories(src_inode, dst_inode);
}
+ /*
+ * If either the source or the destination file was opened with O_SYNC,
+ * O_DSYNC or has the S_SYNC attribute, fsync both the destination and
+ * source files/ranges, so that after a successful return (0) followed
+ * by a power failure results in the reflinked data to be readable from
+ * both files/ranges.
+ */
+ if (ret == 0 && len > 0 &&
+ (file_sync_write(src_file) || file_sync_write(dst_file))) {
+ ret = btrfs_sync_file(src_file, off, off + len - 1, 0);
+ if (ret == 0)
+ ret = btrfs_sync_file(dst_file, destoff,
+ destoff + len - 1, 0);
+ }
+
return ret < 0 ? ret : len;
}