Add support for --replace and --with

--replace can be used to replace a device without completely failing
it.  Once the replacement completes the device will be failed.
--with can indicate which of several spares to use.

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

diff --git a/Manage.c b/Manage.c
index 296feeb7f6f424adc31831212a91dfa323a6fa8f..832e84ce6051f8c4f1b784d1f0b46c987bdcaae3 100644 (file)
--- a/Manage.c
+++ b/Manage.c
@@ -954,6 +954,111 @@ int Manage_remove(struct supertype *tst, int fd, struct mddev_dev *dv,
        return 1;
 }
 
+int Manage_replace(struct supertype *tst, int fd, struct mddev_dev *dv,
+                  unsigned long rdev, int verbose, char *devname)
+{
+       struct mdinfo *mdi, *di;
+       if (tst->ss->external) {
+               pr_err("--replace only supported for native metadata (0.90 or 1.x)\n");
+               return -1;
+       }
+       /* Need to find the device in sysfs and add 'want_replacement' to the
+        * status.
+        */
+       mdi = sysfs_read(fd, -1, GET_DEVS);
+       if (!mdi || !mdi->devs) {
+               pr_err("Cannot find status of %s to enable replacement - strange\n",
+                      devname);
+               return -1;
+       }
+       for (di = mdi->devs; di; di = di->next)
+               if (di->disk.major == (int)major(rdev) &&
+                   di->disk.minor == (int)minor(rdev))
+                       break;
+       if (di) {
+               int rv;
+               if (di->disk.raid_disk < 0) {
+                       pr_err("%s is not active and so cannot be replaced.\n",
+                              dv->devname);
+                       sysfs_free(mdi);
+                       return -1;
+               }
+               rv = sysfs_set_str(mdi, di,
+                                  "state", "want_replacement");
+               if (rv) {
+                       sysfs_free(mdi);
+                       pr_err("Failed to request replacement for %s\n",
+                              dv->devname);
+                       return -1;
+               }
+               if (verbose >= 0)
+                       pr_err("Marked %s (device %d in %s) for replacement\n",
+                              dv->devname, di->disk.raid_disk, devname);
+               /* If there is a matching 'with', we need to tell it which
+                * raid disk
+                */
+               while (dv && dv->disposition != 'W')
+                       dv = dv->next;
+               if (dv) {
+                       dv->disposition = 'w';
+                       dv->used = di->disk.raid_disk;
+               }
+               return 1;
+       }
+       sysfs_free(mdi);
+       pr_err("%s not found in %s so cannot --replace it\n",
+              dv->devname, devname);
+       return -1;
+}
+
+int Manage_with(struct supertype *tst, int fd, struct mddev_dev *dv,
+               unsigned long rdev, int verbose, char *devname)
+{
+       struct mdinfo *mdi, *di;
+       /* try to set 'slot' for 'rdev' in 'fd' to 'dv->used' */
+       mdi = sysfs_read(fd, -1, GET_DEVS|GET_STATE);
+       if (!mdi || !mdi->devs) {
+               pr_err("Cannot find status of %s to enable replacement - strange\n",
+                      devname);
+               return -1;
+       }
+       for (di = mdi->devs; di; di = di->next)
+               if (di->disk.major == (int)major(rdev) &&
+                   di->disk.minor == (int)minor(rdev))
+                       break;
+       if (di) {
+               int rv;
+               if (di->disk.state & (1<<MD_DISK_FAULTY)) {
+                       pr_err("%s is faulty and cannot be a replacement\n",
+                              dv->devname);
+                       sysfs_free(mdi);
+                       return -1;
+               }
+               if (di->disk.raid_disk >= 0) {
+                       pr_err("%s is active and cannot be a replacement\n",
+                              dv->devname);
+                       sysfs_free(mdi);
+                       return -1;
+               }
+               rv = sysfs_set_num(mdi, di,
+                                  "slot", dv->used);
+               if (rv) {
+                       sysfs_free(mdi);
+                       pr_err("Failed to %s as preferred replacement.\n",
+                              dv->devname);
+                       return -1;
+               }
+               if (verbose >= 0)
+                       pr_err("Marked %s in %s as replacement for device %d\n",
+                              dv->devname, devname, dv->used);
+               return 1;
+       }
+       sysfs_free(mdi);
+       pr_err("%s not found in %s so cannot make it preferred replacement\n",
+              dv->devname, devname);
+       return -1;
+}
+
 int Manage_subdevs(char *devname, int fd,
                   struct mddev_dev *devlist, int verbose, int test,
                   char *update, int force)
@@ -970,6 +1075,16 @@ int Manage_subdevs(char *devname, int fd,
         *  'f' - set the device faulty SET_DISK_FAULTY
         *        device can be 'detached' in which case any device that
         *        is inaccessible will be marked faulty.
+        *  'R' - mark this device as wanting replacement.
+        *  'W' - this device is added if necessary and activated as
+        *        a replacement for a previous 'R' device.
+        * -----
+        *  'w' - 'W' will be changed to 'w' when it is paired with
+        *        a 'R' device.  If a 'W' is found while walking the list
+        *        it must be unpaired, and is an error.
+        *  'M' - this is created by a 'missing' target.  It is a slight
+        *        variant on 'A'
+        *
         * For 'f' and 'r', the device can also be a kernel-internal
         * name such as 'sdb'.
         */
@@ -1209,6 +1324,38 @@ int Manage_subdevs(char *devname, int fd,
                                pr_err("set %s faulty in %s\n",
                                        dv->devname, devname);
                        break;
+               case 'R': /* Mark as replaceable */
+                       if (subarray) {
+                               pr_err("Cannot replace disks in a"
+                                       " \'member\' array, perform this"
+                                       " operation on the parent container\n");
+                               rv = -1;
+                       } else {
+                               if (!frozen) {
+                                       if (sysfs_freeze_array(&info) == 1)
+                                               frozen = 1;
+                                       else
+                                               frozen = -1;
+                               }
+                               rv = Manage_replace(tst, fd, dv,
+                                                   stb.st_rdev, verbose,
+                                                   devname);
+                       }
+                       if (rv < 0)
+                               goto abort;
+                       if (rv > 0)
+                               count++;
+                       break;
+               case 'W': /* --with device that doesn't match */
+                       pr_err("No matching --replace device for --with %s\n",
+                              dv->devname);
+                       goto abort;
+               case 'w': /* --with device which was matched */
+                       rv = Manage_with(tst, fd, dv,
+                                        stb.st_rdev, verbose, devname);
+                       if (rv < 0)
+                               goto abort;
+                       break;
                }
        }
        if (frozen > 0)

diff --git a/ReadMe.c b/ReadMe.c
index 2fde2ac5747eb9f52ed3fe15e542d415c5bbe51a..0aa8cbd70be181aae9c36ad67c80bf5386bd381e 100644 (file)
--- a/ReadMe.c
+++ b/ReadMe.c
@@ -146,6 +146,8 @@ struct option long_options[] = {
     {"remove",    0, 0, Remove},
     {"fail",      0, 0, Fail},
     {"set-faulty",0, 0, Fail},
+    {"replace",   0, 0, Replace},
+    {"with",      0, 0, With},
     {"run",       0, 0, 'R'},
     {"stop",      0, 0, 'S'},
     {"readonly",  0, 0, 'o'},
@@ -309,6 +311,7 @@ char OptionHelp[] =
 "  --remove      -r   : remove subsequent devices\n"
 "  --fail        -f   : mark subsequent devices as faulty\n"
 "  --set-faulty       : same as --fail\n"
+"  --replace          : mark a device for replacement\n"
 "  --run         -R   : start a partially built array\n"
 "  --stop        -S   : deactivate array, releasing all resources\n"
 "  --readonly    -o   : mark array as readonly\n"
@@ -462,6 +465,10 @@ char Help_manage[] =
 "  --remove      -r   : remove subsequent devices, which must not be active\n"
 "  --fail        -f   : mark subsequent devices a faulty\n"
 "  --set-faulty       : same as --fail\n"
+"  --replace          : mark device(s) to be replaced by spares.  Once\n"
+"                     : replacement completes, device will be marked faulty\n"
+"  --with             : Indicate which spare a previous '--replace' should\n"
+"                     : prefer to use\n"
 "  --run         -R   : start a partially built array\n"
 "  --stop        -S   : deactivate array, releasing all resources\n"
 "  --readonly    -o   : mark array as readonly\n"

diff --git a/mdadm.8.in b/mdadm.8.in
index d30963b66488ecbf394f9cab3fd2f1e013d458f6..23e31228d37b9074f9410ceaabecbe97f2f824cc 100644 (file)
--- a/mdadm.8.in
+++ b/mdadm.8.in
@@ -216,8 +216,9 @@ to detect and assemble arrays \(em possibly in an
 If a device is given before any options, or if the first option is
 .BR \-\-add ,
 .BR \-\-fail ,
-or
 .BR \-\-remove ,
+or
+.BR \-\-replace ,
 then the MANAGE mode is assumed.
 Anything other than these will cause the
 .B Misc
@@ -1283,7 +1284,7 @@ have already been marked as failed.
 
 .TP
 .BR \-f ", " \-\-fail
-mark listed devices as faulty.
+Mark listed devices as faulty.
 As well as the name of a device file, the word
 .B detached
 can be given.  This will cause any device that has been detached from
@@ -1294,6 +1295,25 @@ the system to be marked as failed.  It can then be removed.
 same as
 .BR \-\-fail .
 
+.TP
+.B \-\-replace
+Mark listed devices as requiring replacement.  As soon as a spare is
+available, it will be rebuilt and will replace the marked device.
+This is similar to marking a device as faulty, but the device remains
+in service during the recovery process to increase resilience against
+multiple failures.  When the replacement process finishes, the
+replaced device will be marked as faulty.
+
+.TP
+.B \-\-with
+This can follow a list of
+.B \-\-replace
+devices.  The devices listed after
+.B \-\-with
+will be preferentially used to replace the devices listed after
+.BR \-\-replace .
+These device must already be spare devices in the array.
+
 .TP
 .BR \-\-write\-mostly
 Subsequent devices that are added or re\-added will have the 'write-mostly'

diff --git a/mdadm.c b/mdadm.c
index 42544f1affbe448d4a3f37ae32366dd67d3ca08c..11016e7b911be9fd219a7cb717d92b34ac448a58 100644 (file)
--- a/mdadm.c
+++ b/mdadm.c
@@ -195,6 +195,8 @@ int main(int argc, char *argv[])
                case Add:
                case 'r':
                case Remove:
+               case Replace:
+               case With:
                case 'f':
                case Fail:
                case ReAdd: /* re-add */
@@ -928,6 +930,18 @@ int main(int argc, char *argv[])
                                           * remove the device */
                        devmode = 'f';
                        continue;
+               case O(MANAGE,Replace):
+                       /* Mark these devices for replacement */
+                       devmode = 'R';
+                       continue;
+               case O(MANAGE,With):
+                       /* These are the replacements to use */
+                       if (devmode != 'R') {
+                               pr_err("--with must follow --replace\n");
+                               exit(2);
+                       }
+                       devmode = 'W';
+                       continue;
                case O(INCREMENTAL,'R'):
                case O(MANAGE,'R'):
                case O(ASSEMBLE,'R'):

diff --git a/mdadm.h b/mdadm.h
index ac051178a711deb3eb52d3a724e5134f1dbccdf5..f1352e3704a357ca43d4d40ec8db67ce6b615670 100644 (file)
--- a/mdadm.h
+++ b/mdadm.h
@@ -312,6 +312,8 @@ enum special_options {
        Add,
        Remove,
        Fail,
+       Replace,
+       With,
        MiscOpt,
        WaitOpt,
        ConfigFile,
@@ -432,7 +434,7 @@ struct mddev_dev {
                                 * Not set for names read from .config
                                 */
        char writemostly;       /* 1 for 'set writemostly', 2 for 'clear writemostly' */
-       char used;              /* set when used */
+       int used;               /* set when used */
        long long data_offset;
        struct mddev_dev *next;
 };