Correctly remove logical partition maps

kpartx will generate logical partition maps inside maps for the
extended partition. So we need to update multipath -f to handle
this situation.

Signed-off-by: Cong Meng <cmeng@novell.com>
Signed-off-by: Hannes Reinecke <hare@suse.de>

diff --git a/libmultipath/devmapper.c b/libmultipath/devmapper.c
index 131930c..1e09333 100644 (file)
--- a/libmultipath/devmapper.c
+++ b/libmultipath/devmapper.c
@@ -427,8 +427,8 @@ out:
        return r;
 }
 
-extern int
-dm_get_uuid(char *name, char *uuid)
+static int
+dm_get_prefixed_uuid(const char *name, char *uuid)
 {
        struct dm_task *dmt;
        const char *uuidtmp;
@@ -445,12 +445,8 @@ dm_get_uuid(char *name, char *uuid)
                goto uuidout;
 
        uuidtmp = dm_task_get_uuid(dmt);
-       if (uuidtmp) {
-               if (!strncmp(uuidtmp, UUID_PREFIX, UUID_PREFIX_LEN))
-                       strcpy(uuid, uuidtmp + UUID_PREFIX_LEN);
-               else
-                       strcpy(uuid, uuidtmp);
-       }
+       if (uuidtmp)
+               strcpy(uuid, uuidtmp);
        else
                uuid[0] = '\0';
 
@@ -461,6 +457,47 @@ uuidout:
 }
 
 extern int
+dm_get_uuid(char *name, char *uuid)
+{
+       char uuidtmp[WWID_SIZE];
+
+       if (dm_get_prefixed_uuid(name, uuidtmp))
+               return 1;
+
+       if (!strncmp(uuidtmp, UUID_PREFIX, UUID_PREFIX_LEN))
+               strcpy(uuid, uuidtmp + UUID_PREFIX_LEN);
+       else
+               strcpy(uuid, uuidtmp);
+
+       return 0;
+}
+
+/*
+ * returns:
+ *    0 : if both uuids end with same suffix which starts with UUID_PREFIX
+ *    1 : otherwise
+ */
+int
+dm_compare_uuid(const char* mapname1, const char* mapname2)
+{
+       char *p1, *p2;
+       char uuid1[WWID_SIZE], uuid2[WWID_SIZE];
+
+       if (dm_get_prefixed_uuid(mapname1, uuid1))
+               return 1;
+
+       if (dm_get_prefixed_uuid(mapname2, uuid2))
+               return 1;
+
+       p1 = strstr(uuid1, UUID_PREFIX);
+       p2 = strstr(uuid2, UUID_PREFIX);
+       if (p1 && p2 && !strcmp(p1, p2))
+               return 0;
+
+       return 1;
+}
+
+extern int
 dm_get_status(char * name, char * outstatus)
 {
        int r = 1;
@@ -1018,15 +1055,10 @@ dm_remove_partmaps (const char * mapname, int need_sync)
                    (dm_type(names->name, TGT_PART) > 0) &&
 
                    /*
-                    * and the multipath mapname and the part mapname start
-                    * the same
-                    */
-                   !strncmp(names->name, mapname, strlen(mapname)) &&
-
-                   /*
-                    * and the opencount is 0 for us to allow removal
+                    * and both uuid end with same suffix starting
+                    * at UUID_PREFIX
                     */
-                   !dm_get_opencount(names->name) &&
+                   (!dm_compare_uuid(names->name, mapname)) &&
 
                    /*
                     * and we can fetch the map table from the kernel
@@ -1038,14 +1070,27 @@ dm_remove_partmaps (const char * mapname, int need_sync)
                     */
                    strstr(params, dev_t)
                   ) {
-                               /*
-                                * then it's a kpartx generated partition.
-                                * remove it.
-                                */
-                               condlog(4, "partition map %s removed",
-                                       names->name);
-                               dm_simplecmd_flush(DM_DEVICE_REMOVE, names->name, need_sync);
-                  }
+                       /*
+                        * then it's a kpartx generated partition.
+                        * remove it.
+                        */
+                       /*
+                        * if the opencount is 0 maybe some other
+                        * partitions depend on it.
+                        */
+                       if (dm_get_opencount(names->name)) {
+                               dm_remove_partmaps(names->name, need_sync);
+                               if (dm_get_opencount(names->name)) {
+                                       condlog(2, "%s: map in use",
+                                               names->name);
+                                       goto out;
+                               }
+                       }
+                       condlog(4, "partition map %s removed",
+                               names->name);
+                       dm_simplecmd_flush(DM_DEVICE_REMOVE, names->name,
+                                          need_sync);
+               }
 
                next = names->next;
                names = (void *) names + next;