Work around bug in --add handling for version-1 superblocks

In 2.6.17 (and prior), the dev_number is ignored when a device
is added to an active array.  Rather the first free number is used.
So we work around this by making sure we use the first free
number for dev_number.

Description...

diff --git a/ChangeLog b/ChangeLog
index c6b1a13bfbf18588c9822515ea9cd5e113f605ea..ecbb598b3a65fd316c12dbf180bc1548fbbe16ba 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -4,6 +4,8 @@ Changes Prior to this release
     -   Stop map_dev from returning [0:0], as that breaks things.
     -   Add 'Array Slot' line to --examine for version-1 superblocks
        to make it a bit easier to see what is happening.
+    -   Work around bug in --add handling for  version-1 superblocks
+       in 2.6.17 (and prior).
 
 Changes Prior to 2.5.1 release
     -   Various fixes for gcc warnings

diff --git a/Manage.c b/Manage.c
index a1e152c8ea8b09da79b1d3092d841f6f0d2aefdb..1067bfe96e90b5b44f7cd2116424b3ee9f05ef97 100644 (file)
--- a/Manage.c
+++ b/Manage.c
@@ -271,8 +271,14 @@ int Manage_subdevs(char *devname, int fd,
                                 * If so, we can simply re-add it.
                                 */
                                st->ss->uuid_from_super(duuid, dsuper);
-                       
-                               if (osuper) {
+
+                               /* re-add doesn't work for version-1 superblocks
+                                * before 2.6.18 :-(
+                                */
+                               if (array.major_version == 1 &&
+                                   get_linux_version() <= 2006018)
+                                       ;
+                               else if (osuper) {
                                        st->ss->uuid_from_super(ouuid, osuper);
                                        if (memcmp(duuid, ouuid, sizeof(ouuid))==0) {
                                                /* look close enough for now.  Kernel
@@ -295,7 +301,12 @@ int Manage_subdevs(char *devname, int fd,
                                        }
                                }
                        }
-                       for (j=0; j< st->max_devs; j++) {
+                       /* in 2.6.17 and earlier, version-1 superblocks won't
+                        * use the number we write, but will choose a free number.
+                        * we must choose the same free number, which requires
+                        * starting at 'raid_disks' and counting up
+                        */
+                       for (j = array.raid_disks; j< st->max_devs; j++) {
                                disc.number = j;
                                if (ioctl(fd, GET_DISK_INFO, &disc))
                                        break;

diff --git a/super1.c b/super1.c
index 686215557adf71de8e353a37d3a7d7ed591114cf..8e6703be0ca9a82628859205b0125865a3409abf 100644 (file)
--- a/super1.c
+++ b/super1.c
@@ -779,7 +779,11 @@ static int write_init_super1(struct supertype *st, void *sbv,
                if (memcmp(sb->set_uuid, refsb->set_uuid, 16)==0) {
                        /* same array, so preserve events and dev_number */
                        sb->events = refsb->events;
-                       sb->dev_number = refsb->dev_number;
+                       /* bugs in 2.6.17 and earlier mean the dev_number
+                        * chosen in Manage must be preserved
+                        */
+                       if (get_linux_version() >= 2006018)
+                               sb->dev_number = refsb->dev_number;
                }
                free(refsb);
        }