1 files changed, 17 insertions, 18 deletions

diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index 21ec16b7e6e1..2faaa2976447 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -765,7 +765,7 @@ struct vmap_block {
         spinlock_t lock;
         struct vmap_area *va;
         unsigned long free, dirty;
-        DECLARE_BITMAP(dirty_map, VMAP_BBMAP_BITS);
+        unsigned long dirty_min, dirty_max; /*< dirty range */
         struct list_head free_list;
         struct rcu_head rcu_head;
         struct list_head purge;
@@ -851,7 +851,8 @@ static void *new_vmap_block(unsigned int order, gfp_t gfp_mask)
         BUG_ON(VMAP_BBMAP_BITS <= (1UL << order));
         vb->free = VMAP_BBMAP_BITS - (1UL << order);
         vb->dirty = 0;
-        bitmap_zero(vb->dirty_map, VMAP_BBMAP_BITS);
+        vb->dirty_min = VMAP_BBMAP_BITS;
+        vb->dirty_max = 0;
         INIT_LIST_HEAD(&vb->free_list);
 
         vb_idx = addr_to_vb_idx(va->va_start);
@@ -902,7 +903,8 @@ static void purge_fragmented_blocks(int cpu)
                 if (vb->free + vb->dirty == VMAP_BBMAP_BITS && vb->dirty != VMAP_BBMAP_BITS) {
                         vb->free = 0; /* prevent further allocs after releasing lock */
                         vb->dirty = VMAP_BBMAP_BITS; /* prevent purging it again */
-                        bitmap_fill(vb->dirty_map, VMAP_BBMAP_BITS);
+                        vb->dirty_min = 0;
+                        vb->dirty_max = VMAP_BBMAP_BITS;
                         spin_lock(&vbq->lock);
                         list_del_rcu(&vb->free_list);
                         spin_unlock(&vbq->lock);
@@ -995,6 +997,7 @@ static void vb_free(const void *addr, unsigned long size)
         order = get_order(size);
 
         offset = (unsigned long)addr & (VMAP_BLOCK_SIZE - 1);
+        offset >>= PAGE_SHIFT;
 
         vb_idx = addr_to_vb_idx((unsigned long)addr);
         rcu_read_lock();
@@ -1005,7 +1008,10 @@ static void vb_free(const void *addr, unsigned long size)
         vunmap_page_range((unsigned long)addr, (unsigned long)addr + size);
 
         spin_lock(&vb->lock);
-        BUG_ON(bitmap_allocate_region(vb->dirty_map, offset >> PAGE_SHIFT, order));
+
+        /* Expand dirty range */
+        vb->dirty_min = min(vb->dirty_min, offset);
+        vb->dirty_max = max(vb->dirty_max, offset + (1UL << order));
 
         vb->dirty += 1UL << order;
         if (vb->dirty == VMAP_BBMAP_BITS) {
@@ -1044,25 +1050,18 @@ void vm_unmap_aliases(void)
 
                 rcu_read_lock();
                 list_for_each_entry_rcu(vb, &vbq->free, free_list) {
-                        int i, j;
-
                         spin_lock(&vb->lock);
-                        i = find_first_bit(vb->dirty_map, VMAP_BBMAP_BITS);
-                        if (i < VMAP_BBMAP_BITS) {
+                        if (vb->dirty) {
+                                unsigned long va_start = vb->va->va_start;
                                 unsigned long s, e;
 
-                                j = find_last_bit(vb->dirty_map,
-                                                        VMAP_BBMAP_BITS);
-                                j = j + 1; /* need exclusive index */
+                                s = va_start + (vb->dirty_min << PAGE_SHIFT);
+                                e = va_start + (vb->dirty_max << PAGE_SHIFT);
 
-                                s = vb->va->va_start + (i << PAGE_SHIFT);
-                                e = vb->va->va_start + (j << PAGE_SHIFT);
-                                flush = 1;
+                                start = min(s, start);
+                                end   = max(e, end);
 
-                                if (s < start)
-                                        start = s;
-                                if (e > end)
-                                        end = e;
+                                flush = 1;
                         }
                         spin_unlock(&vb->lock);
                 }