New API: mdadm-create for creating MD devices.

1 files changed, 170 insertions, 0 deletions

diff --git a/daemon/md.c b/daemon/md.c
new file mode 100644
index 00000000..1adb4ac9
--- /dev/null
+++ b/daemon/md.c
@@ -0,0 +1,170 @@
+/* libguestfs - the guestfsd daemon
+ * Copyright (C) 2011 Red Hat Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include <config.h>
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <inttypes.h>
+#include <glob.h>
+
+#include "daemon.h"
+#include "actions.h"
+#include "optgroups.h"
+
+int
+optgroup_mdadm_available (void)
+{
+  return prog_exists ("mdadm");
+}
+
+static size_t
+count_bits (uint64_t bitmap)
+{
+  size_t c;
+
+  if (bitmap == 0)
+    return 0;
+
+  c = bitmap & 1 ? 1 : 0;
+  bitmap >>= 1;
+  return c + count_bits (bitmap);
+}
+
+/* Takes optional arguments, consult optargs_bitmask. */
+int
+do_mdadm_create (const char *name, char *const *devices,
+                 int64_t missingbitmap, int nrdevices, int spare,
+                 int64_t chunk, const char *level)
+{
+  char nrdevices_s[32];
+  char spare_s[32];
+  char chunk_s[32];
+  size_t j;
+  int r;
+  char *err;
+  uint64_t umissingbitmap = (uint64_t) missingbitmap;
+
+  /* Check the optional parameters and set defaults where appropriate. */
+  if (!(optargs_bitmask & GUESTFS_MDADM_CREATE_MISSINGBITMAP_BITMASK))
+    umissingbitmap = 0;
+
+  if (optargs_bitmask & GUESTFS_MDADM_CREATE_SPARE_BITMASK) {
+    if (spare < 0) {
+      reply_with_error ("spare must not be negative");
+      return -1;
+    }
+  }
+  else
+    spare = 0;
+
+  if (optargs_bitmask & GUESTFS_MDADM_CREATE_NRDEVICES_BITMASK) {
+    if (nrdevices < 2) {
+      reply_with_error ("nrdevices is less than 2");
+      return -1;
+    }
+  }
+  else
+    nrdevices = count_strings (devices) + count_bits (umissingbitmap);
+
+  if (optargs_bitmask & GUESTFS_MDADM_CREATE_LEVEL_BITMASK) {
+    if (STRNEQ (level, "linear") && STRNEQ (level, "raid0") &&
+        STRNEQ (level, "0") && STRNEQ (level, "stripe") &&
+        STRNEQ (level, "raid1") && STRNEQ (level, "1") &&
+        STRNEQ (level, "mirror") &&
+        STRNEQ (level, "raid4") && STRNEQ (level, "4") &&
+        STRNEQ (level, "raid5") && STRNEQ (level, "5") &&
+        STRNEQ (level, "raid6") && STRNEQ (level, "6") &&
+        STRNEQ (level, "raid10") && STRNEQ (level, "10")) {
+      reply_with_error ("unknown level parameter: %s", level);
+      return -1;
+    }
+  }
+  else
+    level = "raid1";
+
+  if (optargs_bitmask & GUESTFS_MDADM_CREATE_CHUNK_BITMASK) {
+    /* chunk is bytes in the libguestfs API, but K when we pass it to mdadm */
+    if ((chunk & 1023) != 0) {
+      reply_with_error ("chunk size must be a multiple of 1024 bytes");
+      return -1;
+    }
+  }
+
+  /* Check invariant. */
+  if (count_strings (devices) + count_bits (umissingbitmap) !=
+      (size_t) (nrdevices + spare)) {
+    reply_with_error ("devices (%zu) + bits set in missingbitmap (%zu) is not equal to nrdevices (%d) + spare (%d)",
+                      count_strings (devices), count_bits (umissingbitmap),
+                      nrdevices, spare);
+    return -1;
+  }
+
+  size_t MAX_ARGS = nrdevices + 16;
+  const char *argv[MAX_ARGS];
+  size_t i = 0;
+
+  ADD_ARG (argv, i, "mdadm");
+  ADD_ARG (argv, i, "--create");
+  /* --run suppresses "Continue creating array" question */
+  ADD_ARG (argv, i, "--run");
+  ADD_ARG (argv, i, name);
+  ADD_ARG (argv, i, "--level");
+  ADD_ARG (argv, i, level);
+  ADD_ARG (argv, i, "--raid-devices");
+  snprintf (nrdevices_s, sizeof nrdevices_s, "%d", nrdevices);
+  ADD_ARG (argv, i, nrdevices_s);
+  if (optargs_bitmask & GUESTFS_MDADM_CREATE_SPARE_BITMASK) {
+    ADD_ARG (argv, i, "--spare-devices");
+    snprintf (spare_s, sizeof spare_s, "%d", spare);
+    ADD_ARG (argv, i, spare_s);
+  }
+  if (optargs_bitmask & GUESTFS_MDADM_CREATE_CHUNK_BITMASK) {
+    ADD_ARG (argv, i, "--chunk");
+    snprintf (chunk_s, sizeof chunk_s, "%" PRIi64, chunk / 1024);
+    ADD_ARG (argv, i, chunk_s);
+  }
+
+  /* Add devices and "missing". */
+  j = 0;
+  while (devices[j] != NULL || umissingbitmap != 0) {
+    if (umissingbitmap & 1)
+      ADD_ARG (argv, i, "missing");
+    else {
+      ADD_ARG (argv, i, devices[j]);
+      j++;
+    }
+    umissingbitmap >>= 1;
+  }
+
+  ADD_ARG (argv, i, NULL);
+
+  r = commandv (NULL, &err, argv);
+  if (r == -1) {
+    reply_with_error ("mdadm: %s: %s", name, err);
+    free (err);
+    return -1;
+  }
+
+  free (err);
+
+  udev_settle ();
+
+  return 0;
+}