md-cluster: remove suspend_info

Previously, we allow multiple nodes can resync device, but we
had changed it to only support one node can do resync at one
time, but suspend_info is still used.

Now, let's remove the structure and use suspend_lo/hi to record
the range.

Reviewed-by: NeilBrown <neilb@suse.com>
Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>

diff --git a/drivers/md/md-cluster.c b/drivers/md/md-cluster.c
index f1b8707..8dff19d 100644 (file)
--- a/drivers/md/md-cluster.c
+++ b/drivers/md/md-cluster.c
@@ -33,13 +33,6 @@ struct dlm_lock_resource {
        int mode;
 };
 
-struct suspend_info {
-       int slot;
-       sector_t lo;
-       sector_t hi;
-       struct list_head list;
-};
-
 struct resync_info {
        __le64 lo;
        __le64 hi;
@@ -80,7 +73,13 @@ struct md_cluster_info {
        struct dlm_lock_resource **other_bitmap_lockres;
        struct dlm_lock_resource *resync_lockres;
        struct list_head suspend_list;
+
        spinlock_t suspend_lock;
+       /* record the region which write should be suspended */
+       sector_t suspend_lo;
+       sector_t suspend_hi;
+       int suspend_from; /* the slot which broadcast suspend_lo/hi */
+
        struct md_thread *recovery_thread;
        unsigned long recovery_map;
        /* communication loc resources */
@@ -271,25 +270,22 @@ static void add_resync_info(struct dlm_lock_resource *lockres,
        ri->hi = cpu_to_le64(hi);
 }
 
-static struct suspend_info *read_resync_info(struct mddev *mddev, struct dlm_lock_resource *lockres)
+static int read_resync_info(struct mddev *mddev,
+                           struct dlm_lock_resource *lockres)
 {
        struct resync_info ri;
-       struct suspend_info *s = NULL;
-       sector_t hi = 0;
+       struct md_cluster_info *cinfo = mddev->cluster_info;
+       int ret = 0;
 
        dlm_lock_sync(lockres, DLM_LOCK_CR);
        memcpy(&ri, lockres->lksb.sb_lvbptr, sizeof(struct resync_info));
-       hi = le64_to_cpu(ri.hi);
-       if (hi > 0) {
-               s = kzalloc(sizeof(struct suspend_info), GFP_KERNEL);
-               if (!s)
-                       goto out;
-               s->hi = hi;
-               s->lo = le64_to_cpu(ri.lo);
+       if (le64_to_cpu(ri.hi) > 0) {
+               cinfo->suspend_hi = le64_to_cpu(ri.hi);
+               cinfo->suspend_lo = le64_to_cpu(ri.lo);
+               ret = 1;
        }
        dlm_unlock_sync(lockres);
-out:
-       return s;
+       return ret;
 }
 
 static void recover_bitmaps(struct md_thread *thread)
@@ -299,7 +295,6 @@ static void recover_bitmaps(struct md_thread *thread)
        struct dlm_lock_resource *bm_lockres;
        char str[64];
        int slot, ret;
-       struct suspend_info *s, *tmp;
        sector_t lo, hi;
 
        while (cinfo->recovery_map) {
@@ -326,11 +321,9 @@ static void recover_bitmaps(struct md_thread *thread)
 
                /* Clear suspend_area associated with the bitmap */
                spin_lock_irq(&cinfo->suspend_lock);
-               list_for_each_entry_safe(s, tmp, &cinfo->suspend_list, list)
-                       if (slot == s->slot) {
-                               list_del(&s->list);
-                               kfree(s);
-                       }
+               cinfo->suspend_hi = 0;
+               cinfo->suspend_lo = 0;
+               cinfo->suspend_from = -1;
                spin_unlock_irq(&cinfo->suspend_lock);
 
                /* Kick off a reshape if needed */
@@ -441,24 +434,13 @@ static void ack_bast(void *arg, int mode)
        }
 }
 
-static void __remove_suspend_info(struct md_cluster_info *cinfo, int slot)
-{
-       struct suspend_info *s, *tmp;
-
-       list_for_each_entry_safe(s, tmp, &cinfo->suspend_list, list)
-               if (slot == s->slot) {
-                       list_del(&s->list);
-                       kfree(s);
-                       break;
-               }
-}
-
 static void remove_suspend_info(struct mddev *mddev, int slot)
 {
        struct md_cluster_info *cinfo = mddev->cluster_info;
        mddev->pers->quiesce(mddev, 1);
        spin_lock_irq(&cinfo->suspend_lock);
-       __remove_suspend_info(cinfo, slot);
+       cinfo->suspend_hi = 0;
+       cinfo->suspend_lo = 0;
        spin_unlock_irq(&cinfo->suspend_lock);
        mddev->pers->quiesce(mddev, 0);
 }
@@ -467,7 +449,6 @@ static void process_suspend_info(struct mddev *mddev,
                int slot, sector_t lo, sector_t hi)
 {
        struct md_cluster_info *cinfo = mddev->cluster_info;
-       struct suspend_info *s;
        struct mdp_superblock_1 *sb = NULL;
        struct md_rdev *rdev;
 
@@ -516,17 +497,11 @@ static void process_suspend_info(struct mddev *mddev,
        cinfo->sync_low = lo;
        cinfo->sync_hi = hi;
 
-       s = kzalloc(sizeof(struct suspend_info), GFP_KERNEL);
-       if (!s)
-               return;
-       s->slot = slot;
-       s->lo = lo;
-       s->hi = hi;
        mddev->pers->quiesce(mddev, 1);
        spin_lock_irq(&cinfo->suspend_lock);
-       /* Remove existing entry (if exists) before adding */
-       __remove_suspend_info(cinfo, slot);
-       list_add(&s->list, &cinfo->suspend_list);
+       cinfo->suspend_from = slot;
+       cinfo->suspend_lo = lo;
+       cinfo->suspend_hi = hi;
        spin_unlock_irq(&cinfo->suspend_lock);
        mddev->pers->quiesce(mddev, 0);
 }
@@ -825,7 +800,6 @@ static int gather_all_resync_info(struct mddev *mddev, int total_slots)
        struct md_cluster_info *cinfo = mddev->cluster_info;
        int i, ret = 0;
        struct dlm_lock_resource *bm_lockres;
-       struct suspend_info *s;
        char str[64];
        sector_t lo, hi;
 
@@ -844,16 +818,13 @@ static int gather_all_resync_info(struct mddev *mddev, int total_slots)
                bm_lockres->flags |= DLM_LKF_NOQUEUE;
                ret = dlm_lock_sync(bm_lockres, DLM_LOCK_PW);
                if (ret == -EAGAIN) {
-                       s = read_resync_info(mddev, bm_lockres);
-                       if (s) {
+                       if (read_resync_info(mddev, bm_lockres)) {
                                pr_info("%s:%d Resync[%llu..%llu] in progress on %d\n",
                                                __func__, __LINE__,
-                                               (unsigned long long) s->lo,
-                                               (unsigned long long) s->hi, i);
-                               spin_lock_irq(&cinfo->suspend_lock);
-                               s->slot = i;
-                               list_add(&s->list, &cinfo->suspend_list);
-                               spin_unlock_irq(&cinfo->suspend_lock);
+                                       (unsigned long long) cinfo->suspend_lo,
+                                       (unsigned long long) cinfo->suspend_hi,
+                                       i);
+                               cinfo->suspend_from = i;
                        }
                        ret = 0;
                        lockres_free(bm_lockres);
@@ -1352,13 +1323,10 @@ static int resync_start(struct mddev *mddev)
 static void resync_info_get(struct mddev *mddev, sector_t *lo, sector_t *hi)
 {
        struct md_cluster_info *cinfo = mddev->cluster_info;
-       struct suspend_info *s;
 
        spin_lock_irq(&cinfo->suspend_lock);
-       list_for_each_entry(s, &cinfo->suspend_list, list) {
-               *lo = s->lo;
-               *hi = s->hi;
-       }
+       *lo = cinfo->suspend_lo;
+       *hi = cinfo->suspend_hi;
        spin_unlock_irq(&cinfo->suspend_lock);
 }
 
@@ -1414,21 +1382,14 @@ static int area_resyncing(struct mddev *mddev, int direction,
 {
        struct md_cluster_info *cinfo = mddev->cluster_info;
        int ret = 0;
-       struct suspend_info *s;
 
        if ((direction == READ) &&
                test_bit(MD_CLUSTER_SUSPEND_READ_BALANCING, &cinfo->state))
                return 1;
 
        spin_lock_irq(&cinfo->suspend_lock);
-       if (list_empty(&cinfo->suspend_list))
-               goto out;
-       list_for_each_entry(s, &cinfo->suspend_list, list)
-               if (hi > s->lo && lo < s->hi) {
-                       ret = 1;
-                       break;
-               }
-out:
+       if (hi > cinfo->suspend_lo && lo < cinfo->suspend_hi)
+               ret = 1;
        spin_unlock_irq(&cinfo->suspend_lock);
        return ret;
 }