Manage: be more careful about --add attempts.

If an --add is requested and a re-add looks promising but fails or
cannot possibly succeed, then don't try the add.  This avoids
inadvertently turning devices into spares when an array is failed but
the devices seem to actually work.

Signed-off-by: NeilBrown <neilb@suse.de>

diff --git a/Manage.c b/Manage.c
index 1b474798c51b91a50aca78822d795473efcd0ced..7ed47310745c48fba7cb71e15b206a6a007f72e1 100644 (file)
--- a/Manage.c
+++ b/Manage.c
@@ -383,6 +383,7 @@ int Manage_subdevs(char *devname, int fd,
                char *dnprintable = dv->devname;
                char *add_dev = dv->devname;
                int err;
+               int re_add_failed = 0;
 
                next = dv->next;
                jnext = 0;
@@ -662,14 +663,20 @@ int Manage_subdevs(char *devname, int fd,
                                    get_linux_version() <= 2006018)
                                        ;
                                else if (st->sb) {
+                                       struct mdinfo mdi;
+                                       st->ss->getinfo_super(st, &mdi);
                                        st->ss->uuid_from_super(st, ouuid);
-                                       if (memcmp(duuid, ouuid, sizeof(ouuid))==0) {
-                                               /* looks close enough for now.  Kernel
-                                                * will worry about whether a bitmap
-                                                * based reconstruction is possible.
+                                       if ((mdi.disk.state & (1<<MD_DISK_ACTIVE)) &&
+                                           !(mdi.disk.state & (1<<MD_DISK_FAULTY)) &&
+                                           memcmp(duuid, ouuid, sizeof(ouuid))==0) {
+                                               /* look like it is worth a try.  Need to
+                                                * make sure kernel will accept it though.
                                                 */
-                                               struct mdinfo mdi;
-                                               st->ss->getinfo_super(st, &mdi);
+                                               disc.number = mdi.disk.number;
+                                               if (ioctl(fd, GET_DISK_INFO, &disc) != 0
+                                                   || disc.major != 0 || disc.minor != 0
+                                                   || !enough_fd(fd))
+                                                       goto skip_re_add;
                                                disc.major = major(stb.st_rdev);
                                                disc.minor = minor(stb.st_rdev);
                                                disc.number = mdi.disk.number;
@@ -684,8 +691,7 @@ int Manage_subdevs(char *devname, int fd,
                                                tfd = -1;
                                                /* don't even try if disk is marked as faulty */
                                                errno = 0;
-                                               if ((disc.state & 1) == 0 &&
-                                                   ioctl(fd, ADD_NEW_DISK, &disc) == 0) {
+                                               if (ioctl(fd, ADD_NEW_DISK, &disc) == 0) {
                                                        if (verbose >= 0)
                                                                fprintf(stderr, Name ": re-added %s\n", add_dev);
                                                        count++;
@@ -698,7 +704,8 @@ int Manage_subdevs(char *devname, int fd,
                                                                continue;
                                                        return 1;
                                                }
-                                               /* fall back on normal-add */
+                                       skip_re_add:
+                                               re_add_failed = 1;
                                        }
                                }
                                if (add_dev != dv->devname) {
@@ -720,6 +727,17 @@ int Manage_subdevs(char *devname, int fd,
                                                dv->devname, devname);
                                        return 1;
                                }
+                               if (re_add_failed) {
+                                       fprintf(stderr, Name ": %s reports being an active member for %s, but a --re-add fails.\n",
+                                               dv->devname, devname);
+                                       fprintf(stderr, Name ": not performing --add as that would convert %s in to a spare.\n",
+                                               dv->devname);
+                                       fprintf(stderr, Name ": To make this a spare, use \"mdadm --zero-superblock %s\" first.\n",     
+                                               dv->devname);
+                                       if (tfd >= 0)
+                                               close(tfd);
+                                       return 1;
+                               }
                        } else {
                                /* non-persistent. Must ensure that new drive
                                 * is at least array.size big.

diff --git a/mdadm.h b/mdadm.h
index 6aa7fc6e526bdaef1782328cd7f541748e80ca66..fcb0e3b32970634ffa80979abdb74290165f1994 100644 (file)
--- a/mdadm.h
+++ b/mdadm.h
@@ -891,6 +891,7 @@ extern char *fname_from_uuid(struct supertype *st,
 extern unsigned long calc_csum(void *super, int bytes);
 extern int enough(int level, int raid_disks, int layout, int clean,
                   char *avail, int avail_disks);
+extern int enough_fd(int fd);
 extern int ask(char *mesg);
 extern unsigned long long get_component_size(int fd);
 extern void remove_partitions(int fd);

diff --git a/tests/01r1fail b/tests/01r1fail
index c3786630935741ed66a7eae5449ec2a64423577b..9f5563210a9f6768bff6c232ea5fc62cfe46077d 100644 (file)
--- a/tests/01r1fail
+++ b/tests/01r1fail
@@ -20,6 +20,7 @@ mdadm $md0 --remove $dev2 $dev1
 check nosync
 check state UUU_
 
+mdadm --zero-superblock $dev2
 mdadm $md0 -a $dev2 
 check recovery
 check wait

diff --git a/util.c b/util.c
index 52171cc230c1b4f418014fa88dd36daf382614ad..cbefaba45a0f3066ddc6116a7ef2582a8a0990c7 100644 (file)
--- a/util.c
+++ b/util.c
@@ -376,6 +376,36 @@ int enough(int level, int raid_disks, int layout, int clean,
        }
 }
 
+int enough_fd(int fd)
+{
+       struct mdu_array_info_s array;
+       struct mdu_disk_info_s disk;
+       int avail_disks = 0;
+       int i;
+       char *avail;
+
+       if (ioctl(fd, GET_ARRAY_INFO, &array) != 0 ||
+           array.raid_disks <= 0)
+               return 0;
+       avail = calloc(array.raid_disks, 1);
+       for (i=0; i<array.raid_disks + array.nr_disks; i++) {
+               disk.number = i;
+               if (ioctl(fd, GET_DISK_INFO, &disk) != 0)
+                       continue;
+               if (! (disk.state & (1<<MD_DISK_SYNC)))
+                       continue;
+               if (disk.raid_disk < 0 || disk.raid_disk >= array.raid_disks)
+                       continue;
+               avail_disks++;
+               avail[disk.raid_disk] = 1;
+       }
+       /* This is used on an active array, so assume it is clean */
+       return enough(array.level, array.raid_disks, array.layout,
+                     1,
+                     avail, avail_disks);
+}
+
+
 const int uuid_match_any[4] = { ~0, ~0, ~0, ~0 };
 int same_uuid(int a[4], int b[4], int swapuuid)
 {