diff options
-rw-r--r-- | mm/vmalloc.c | 58 |
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) |