/*
* Copyright (c) 2016-2017, NVIDIA CORPORATION. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see .
*/
#ifndef PAGE_ALLOCATOR_PRIV_H
#define PAGE_ALLOCATOR_PRIV_H
#include
#include
#include
#include
struct nvgpu_allocator;
/*
* This allocator implements the ability to do SLAB style allocation since the
* GPU has two page sizes available - 4k and 64k/128k. When the default
* granularity is the large page size (64k/128k) small allocations become very
* space inefficient. This is most notable in PDE and PTE blocks which are 4k
* in size.
*
* Thus we need the ability to suballocate in 64k pages. The way we do this for
* the GPU is as follows. We have several buckets for sub-64K allocations:
*
* B0 - 4k
* B1 - 8k
* B3 - 16k
* B4 - 32k
* B5 - 64k (for when large pages are 128k)
*
* When an allocation comes in for less than the large page size (from now on
* assumed to be 64k) the allocation is satisfied by one of the buckets.
*/
struct page_alloc_slab {
struct nvgpu_list_node empty;
struct nvgpu_list_node partial;
struct nvgpu_list_node full;
int nr_empty;
int nr_partial;
int nr_full;
u32 slab_size;
};
enum slab_page_state {
SP_EMPTY,
SP_PARTIAL,
SP_FULL,
SP_NONE
};
struct page_alloc_slab_page {
unsigned long bitmap;
u64 page_addr;
u32 slab_size;
u32 nr_objects;
u32 nr_objects_alloced;
enum slab_page_state state;
struct page_alloc_slab *owner;
struct nvgpu_list_node list_entry;
};
static inline struct page_alloc_slab_page *
page_alloc_slab_page_from_list_entry(struct nvgpu_list_node *node)
{
return (struct page_alloc_slab_page *)
((uintptr_t)node - offsetof(struct page_alloc_slab_page, list_entry));
};
struct page_alloc_chunk {
struct nvgpu_list_node list_entry;
u64 base;
u64 length;
};
static inline struct page_alloc_chunk *
page_alloc_chunk_from_list_entry(struct nvgpu_list_node *node)
{
return (struct page_alloc_chunk *)
((uintptr_t)node - offsetof(struct page_alloc_chunk, list_entry));
};
/*
* Struct to handle internal management of page allocation. It holds a list
* of the chunks of pages that make up the overall allocation - much like a
* scatter gather table.
*/
struct nvgpu_page_alloc {
struct nvgpu_list_node alloc_chunks;
int nr_chunks;
u64 length;
/*
* Only useful for the RB tree - since the alloc may have discontiguous
* pages the base is essentially irrelevant except for the fact that it
* is guarenteed to be unique.
*/
u64 base;
struct nvgpu_rbtree_node tree_entry;
/*
* Set if this is a slab alloc. Points back to the slab page that owns
* this particular allocation. nr_chunks will always be 1 if this is
* set.
*/
struct page_alloc_slab_page *slab_page;
};
static inline struct nvgpu_page_alloc *
nvgpu_page_alloc_from_rbtree_node(struct nvgpu_rbtree_node *node)
{
return (struct nvgpu_page_alloc *)
((uintptr_t)node - offsetof(struct nvgpu_page_alloc, tree_entry));
};
struct nvgpu_page_allocator {
struct nvgpu_allocator *owner; /* Owner of this allocator. */
/*
* Use a buddy allocator to manage the allocation of the underlying
* pages. This lets us abstract the discontiguous allocation handling
* out of the annoyingly complicated buddy allocator.
*/
struct nvgpu_allocator source_allocator;
/*
* Page params.
*/
u64 base;
u64 length;
u64 page_size;
u32 page_shift;
struct nvgpu_rbtree_node *allocs; /* Outstanding allocations. */
struct page_alloc_slab *slabs;
int nr_slabs;
struct nvgpu_kmem_cache *alloc_cache;
struct nvgpu_kmem_cache *chunk_cache;
struct nvgpu_kmem_cache *slab_page_cache;
u64 flags;
/*
* Stat tracking.
*/
u64 nr_allocs;
u64 nr_frees;
u64 nr_fixed_allocs;
u64 nr_fixed_frees;
u64 nr_slab_allocs;
u64 nr_slab_frees;
u64 pages_alloced;
u64 pages_freed;
};
static inline struct nvgpu_page_allocator *page_allocator(
struct nvgpu_allocator *a)
{
return (struct nvgpu_page_allocator *)(a)->priv;
}
static inline struct nvgpu_allocator *palloc_owner(
struct nvgpu_page_allocator *a)
{
return a->owner;
}
#endif