md: change hot_remove_disk to take an rdev rather than a number.

Soon an array will be able to have multiple devices with the
same raid_disk number (an original and a replacement).  So removing
a device based on the number won't work.  So pass the actual device
handle instead.

Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: NeilBrown <neilb@suse.de>

6 files changed, 18 insertions, 21 deletions

diff --git a/drivers/md/md.c b/drivers/md/md.c
index d51c688d9c94..0e2288824938 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -2689,7 +2689,7 @@ slot_store(struct md_rdev *rdev, const char *buf, size_t len)
                 if (rdev->mddev->pers->hot_remove_disk == NULL)
                         return -EINVAL;
                 err = rdev->mddev->pers->
-                        hot_remove_disk(rdev->mddev, rdev->raid_disk);
+                        hot_remove_disk(rdev->mddev, rdev);
                 if (err)
                         return err;
                 sysfs_unlink_rdev(rdev->mddev, rdev);
@@ -7340,7 +7340,7 @@ static int remove_and_add_spares(struct mddev *mddev)
                      ! test_bit(In_sync, &rdev->flags)) &&
                     atomic_read(&rdev->nr_pending)==0) {
                         if (mddev->pers->hot_remove_disk(
-                                    mddev, rdev->raid_disk)==0) {
+                                    mddev, rdev) == 0) {
                                 sysfs_unlink_rdev(mddev, rdev);
                                 rdev->raid_disk = -1;
                         }
@@ -7477,7 +7477,7 @@ void md_check_recovery(struct mddev *mddev)
                                     test_bit(Faulty, &rdev->flags) &&
                                     atomic_read(&rdev->nr_pending)==0) {
                                         if (mddev->pers->hot_remove_disk(
-                                                    mddev, rdev->raid_disk)==0) {
+                                                    mddev, rdev) == 0) {
                                                 sysfs_unlink_rdev(mddev, rdev);
                                                 rdev->raid_disk = -1;
                                         }
diff --git a/drivers/md/md.h b/drivers/md/md.h
index cf742d9306ec..670c10e6b484 100644
--- a/drivers/md/md.h
+++ b/drivers/md/md.h
@@ -428,7 +428,7 @@ struct md_personality
          */
         void (*error_handler)(struct mddev *mddev, struct md_rdev *rdev);
         int (*hot_add_disk) (struct mddev *mddev, struct md_rdev *rdev);
-        int (*hot_remove_disk) (struct mddev *mddev, int number);
+        int (*hot_remove_disk) (struct mddev *mddev, struct md_rdev *rdev);
         int (*spare_active) (struct mddev *mddev);
         sector_t (*sync_request)(struct mddev *mddev, sector_t sector_nr, int *skipped, int go_faster);
         int (*resize) (struct mddev *mddev, sector_t sectors);
diff --git a/drivers/md/multipath.c b/drivers/md/multipath.c
index 5899246fa37e..a222f516660e 100644
--- a/drivers/md/multipath.c
+++ b/drivers/md/multipath.c
@@ -292,17 +292,16 @@ static int multipath_add_disk(struct mddev *mddev, struct md_rdev *rdev)
         return err;
 }
 
-static int multipath_remove_disk(struct mddev *mddev, int number)
+static int multipath_remove_disk(struct mddev *mddev, struct md_rdev *rdev)
 {
         struct mpconf *conf = mddev->private;
         int err = 0;
-        struct md_rdev *rdev;
+        int number = rdev->raid_disk;
         struct multipath_info *p = conf->multipaths + number;
 
         print_multipath_conf(conf);
 
-        rdev = p->rdev;
-        if (rdev) {
+        if (rdev == p->rdev) {
                 if (test_bit(In_sync, &rdev->flags) ||
                     atomic_read(&rdev->nr_pending)) {
                         printk(KERN_ERR "hot-remove-disk, slot %d is identified"
diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
index ede2461e79c5..4317f8de143a 100644
--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -1327,16 +1327,15 @@ static int raid1_add_disk(struct mddev *mddev, struct md_rdev *rdev)
         return err;
 }
 
-static int raid1_remove_disk(struct mddev *mddev, int number)
+static int raid1_remove_disk(struct mddev *mddev, struct md_rdev *rdev)
 {
         struct r1conf *conf = mddev->private;
         int err = 0;
-        struct md_rdev *rdev;
+        int number = rdev->raid_disk;
         struct mirror_info *p = conf->mirrors+ number;
 
         print_conf(conf);
-        rdev = p->rdev;
-        if (rdev) {
+        if (rdev == p->rdev) {
                 if (test_bit(In_sync, &rdev->flags) ||
                     atomic_read(&rdev->nr_pending)) {
                         err = -EBUSY;
diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c
index 685ddf325ee4..f5088dda4dca 100644
--- a/drivers/md/raid10.c
+++ b/drivers/md/raid10.c
@@ -1385,16 +1385,15 @@ static int raid10_add_disk(struct mddev *mddev, struct md_rdev *rdev)
         return err;
 }
 
-static int raid10_remove_disk(struct mddev *mddev, int number)
+static int raid10_remove_disk(struct mddev *mddev, struct md_rdev *rdev)
 {
         struct r10conf *conf = mddev->private;
         int err = 0;
-        struct md_rdev *rdev;
+        int number = rdev->raid_disk;
         struct mirror_info *p = conf->mirrors+ number;
 
         print_conf(conf);
-        rdev = p->rdev;
-        if (rdev) {
+        if (rdev == p->rdev) {
                 if (test_bit(In_sync, &rdev->flags) ||
                     atomic_read(&rdev->nr_pending)) {
                         err = -EBUSY;
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index a68c49250ed5..6b9fc58e8f2d 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -5038,16 +5038,15 @@ static int raid5_spare_active(struct mddev *mddev)
         return count;
 }
 
-static int raid5_remove_disk(struct mddev *mddev, int number)
+static int raid5_remove_disk(struct mddev *mddev, struct md_rdev *rdev)
 {
         struct r5conf *conf = mddev->private;
         int err = 0;
-        struct md_rdev *rdev;
+        int number = rdev->raid_disk;
         struct disk_info *p = conf->disks + number;
 
         print_raid5_conf(conf);
-        rdev = p->rdev;
-        if (rdev) {
+        if (rdev == p->rdev) {
                 if (number >= conf->raid_disks &&
                     conf->reshape_progress == MaxSector)
                         clear_bit(In_sync, &rdev->flags);
@@ -5369,7 +5368,8 @@ static void raid5_finish_reshape(struct mddev *mddev)
                              d < conf->raid_disks - mddev->delta_disks;
                              d++) {
                                 struct md_rdev *rdev = conf->disks[d].rdev;
-                                if (rdev && raid5_remove_disk(mddev, d) == 0) {
+                                if (rdev &&
+                                    raid5_remove_disk(mddev, rdev) == 0) {
                                         sysfs_unlink_rdev(mddev, rdev);
                                         rdev->raid_disk = -1;
                                 }