Relax restrictions on when --add is permitted.

The restriction that --add was not allowed on a device which
looked like a recent member of an array was overly harsh.

The real requirement was to avoid using --add when the array had
failed, and the device being added might contain necessary
information which can only be incorporated by stopping and
re-assembling with --force.

So change the test to reflect the need.

Reported-by: Doug Ledford <dledford@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.de>

diff --git a/Manage.c b/Manage.c
index 3767f019740db61db57dbd22c7768d4fffd9d2be..95aa2704bcccae60e3d65b1c2ff1da313a1ec89f 100644 (file)
--- a/Manage.c
+++ b/Manage.c
@@ -448,7 +448,7 @@ int Manage_subdevs(char *devname, int fd,
                char *dnprintable = dv->devname;
                char *add_dev = dv->devname;
                int err;
-               int re_add_failed = 0;
+               int array_failed;
 
                next = dv->next;
                jnext = 0;
@@ -851,9 +851,8 @@ int Manage_subdevs(char *devname, int fd,
                                                                continue;
                                                        goto abort;
                                                }
-                                       skip_re_add:
-                                               re_add_failed = 1;
                                        }
+                               skip_re_add:
                                        st->ss->free_super(st);
                                }
                                if (add_dev != dv->devname) {
@@ -875,12 +874,30 @@ int Manage_subdevs(char *devname, int fd,
                                                dv->devname, devname);
                                        goto abort;
                                }
-                               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",     
+                               if (array.active_disks < array.raid_disks) {
+                                       char *avail = calloc(array.raid_disks, 1);
+                                       int d;
+                                       int found = 0;
+
+                                       for (d = 0; d < MAX_DISKS && found < array.active_disks; d++) {
+                                               disc.number = d;
+                                               if (ioctl(fd, GET_DISK_INFO, &disc))
+                                                       continue;
+                                               if (disc.major == 0 && disc.minor == 0)
+                                                       continue;
+                                               if (!(disc.state & (1<<MD_DISK_SYNC)))
+                                                       continue;
+                                               avail[disc.raid_disk] = 1;
+                                               found++;
+                                       }
+                                       array_failed = !enough(array.level, array.raid_disks, 
+                                                              array.layout, 1, avail);
+                               } else
+                                       array_failed = 0;
+                               if (array_failed) {
+                                       fprintf(stderr, Name ": %s has failed so using --add cannot work and might destroy\n",
+                                               devname);
+                                       fprintf(stderr, Name ": data on %s.  You should stop the array and re-assemble it.\n",
                                                dv->devname);
                                        if (tfd >= 0)
                                                close(tfd);