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>

1 files changed, 32 insertions, 71 deletions

diff --git a/drivers/md/md-cluster.c b/drivers/md/md-cluster.c
index f1b870766deb..8dff19d5502e 100644
--- 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;
 }