1 files changed, 37 insertions, 21 deletions

diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index 84feb5249b12..21ec16b7e6e1 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -796,13 +796,31 @@ static unsigned long addr_to_vb_idx(unsigned long addr)
         return addr;
 }
 
-static struct vmap_block *new_vmap_block(gfp_t gfp_mask)
+static void *vmap_block_vaddr(unsigned long va_start, unsigned long pages_off)
+{
+        unsigned long addr;
+
+        addr = va_start + (pages_off << PAGE_SHIFT);
+        BUG_ON(addr_to_vb_idx(addr) != addr_to_vb_idx(va_start));
+        return (void *)addr;
+}
+
+/**
+ * new_vmap_block - allocates new vmap_block and occupies 2^order pages in this
+ *                  block. Of course pages number can't exceed VMAP_BBMAP_BITS
+ * @order:    how many 2^order pages should be occupied in newly allocated block
+ * @gfp_mask: flags for the page level allocator
+ *
+ * Returns: virtual address in a newly allocated block or ERR_PTR(-errno)
+ */
+static void *new_vmap_block(unsigned int order, gfp_t gfp_mask)
 {
         struct vmap_block_queue *vbq;
         struct vmap_block *vb;
         struct vmap_area *va;
         unsigned long vb_idx;
         int node, err;
+        void *vaddr;
 
         node = numa_node_id();
 
@@ -826,9 +844,12 @@ static struct vmap_block *new_vmap_block(gfp_t gfp_mask)
                 return ERR_PTR(err);
         }
 
+        vaddr = vmap_block_vaddr(va->va_start, 0);
         spin_lock_init(&vb->lock);
         vb->va = va;
-        vb->free = VMAP_BBMAP_BITS;
+        /* At least something should be left free */
+        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);
         INIT_LIST_HEAD(&vb->free_list);
@@ -846,7 +867,7 @@ static struct vmap_block *new_vmap_block(gfp_t gfp_mask)
         spin_unlock(&vbq->lock);
         put_cpu_var(vmap_block_queue);
 
-        return vb;
+        return vaddr;
 }
 
 static void free_vmap_block(struct vmap_block *vb)
@@ -910,7 +931,7 @@ static void *vb_alloc(unsigned long size, gfp_t gfp_mask)
 {
         struct vmap_block_queue *vbq;
         struct vmap_block *vb;
-        unsigned long addr = 0;
+        void *vaddr = NULL;
         unsigned int order;
 
         BUG_ON(size & ~PAGE_MASK);
@@ -925,43 +946,38 @@ static void *vb_alloc(unsigned long size, gfp_t gfp_mask)
         }
         order = get_order(size);
 
-again:
         rcu_read_lock();
         vbq = &get_cpu_var(vmap_block_queue);
         list_for_each_entry_rcu(vb, &vbq->free, free_list) {
-                int i;
+                unsigned long pages_off;
 
                 spin_lock(&vb->lock);
-                if (vb->free < 1UL << order)
-                        goto next;
+                if (vb->free < (1UL << order)) {
+                        spin_unlock(&vb->lock);
+                        continue;
+                }
 
-                i = VMAP_BBMAP_BITS - vb->free;
-                addr = vb->va->va_start + (i << PAGE_SHIFT);
-                BUG_ON(addr_to_vb_idx(addr) !=
-                                addr_to_vb_idx(vb->va->va_start));
+                pages_off = VMAP_BBMAP_BITS - vb->free;
+                vaddr = vmap_block_vaddr(vb->va->va_start, pages_off);
                 vb->free -= 1UL << order;
                 if (vb->free == 0) {
                         spin_lock(&vbq->lock);
                         list_del_rcu(&vb->free_list);
                         spin_unlock(&vbq->lock);
                 }
+
                 spin_unlock(&vb->lock);
                 break;
-next:
-                spin_unlock(&vb->lock);
         }
 
         put_cpu_var(vmap_block_queue);
         rcu_read_unlock();
 
-        if (!addr) {
-                vb = new_vmap_block(gfp_mask);
-                if (IS_ERR(vb))
-                        return vb;
-                goto again;
-        }
+        /* Allocate new block if nothing was found */
+        if (!vaddr)
+                vaddr = new_vmap_block(order, gfp_mask);
 
-        return (void *)addr;
+        return vaddr;
 }
 
 static void vb_free(const void *addr, unsigned long size)