xfs_io: add fpunch command for hole punching via fallocate

Add a fpunch command which simply uses fallocate to punch a hole for the
given offset and length.

Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>

diff --git a/io/prealloc.c b/io/prealloc.c
index 49ae295a31f2eebb748cab2fe6af9ad06a9847ec..2cf217294393cd43b86b7eac35029c4c5f167ab4 100644 (file)
--- a/io/prealloc.c
+++ b/io/prealloc.c
@@ -36,6 +36,7 @@ static cmdinfo_t unresvsp_cmd;
 static cmdinfo_t zero_cmd;
 #if defined(HAVE_FALLOCATE)
 static cmdinfo_t falloc_cmd;
+static cmdinfo_t fpunch_cmd;
 #endif
 
 static int
@@ -183,7 +184,26 @@ fallocate_f(
        }
        return 0;
 }
-#endif
+
+static int
+fpunch_f(
+        int            argc,
+        char           **argv)
+{
+       xfs_flock64_t   segment;
+       int             mode = FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE;
+
+       if (!offset_length(argv[1], argv[2], &segment))
+               return 0;
+
+       if (fallocate(file->fd, mode,
+                       segment.l_start, segment.l_len)) {
+               perror("fallocate");
+               return 0;
+       }
+       return 0;
+}
+#endif /* HAVE_FALLOCATE */
 
 void
 prealloc_init(void)
@@ -246,7 +266,16 @@ prealloc_init(void)
        falloc_cmd.args = _("[-k] [-p] off len");
        falloc_cmd.oneline =
                _("allocates space associated with part of a file via fallocate");
-
        add_command(&falloc_cmd);
-#endif
+
+       fpunch_cmd.name = _("fpunch");
+       fpunch_cmd.cfunc = fpunch_f;
+       fpunch_cmd.argmin = 2;
+       fpunch_cmd.argmax = 2;
+       fpunch_cmd.flags = CMD_NOMAP_OK | CMD_FOREIGN_OK;
+       fpunch_cmd.args = _("off len");
+       fpunch_cmd.oneline =
+               _("de-allocates space assocated with part of a file via fallocate");
+       add_command(&fpunch_cmd);
+#endif /* HAVE_FALLOCATE */
 }