1 | /* SPDX-License-Identifier: GPL-2.0 */ |
2 | |
3 | #ifndef _NET_PAGE_POOL_TYPES_H |
4 | #define _NET_PAGE_POOL_TYPES_H |
5 | |
6 | #include <linux/dma-direction.h> |
7 | #include <linux/ptr_ring.h> |
8 | #include <linux/types.h> |
9 | |
10 | #define PP_FLAG_DMA_MAP BIT(0) /* Should page_pool do the DMA |
11 | * map/unmap |
12 | */ |
13 | #define PP_FLAG_DMA_SYNC_DEV BIT(1) /* If set all pages that the driver gets |
14 | * from page_pool will be |
15 | * DMA-synced-for-device according to |
16 | * the length provided by the device |
17 | * driver. |
18 | * Please note DMA-sync-for-CPU is still |
19 | * device driver responsibility |
20 | */ |
21 | #define PP_FLAG_SYSTEM_POOL BIT(2) /* Global system page_pool */ |
22 | #define PP_FLAG_ALL (PP_FLAG_DMA_MAP | PP_FLAG_DMA_SYNC_DEV | \ |
23 | PP_FLAG_SYSTEM_POOL) |
24 | |
25 | /* |
26 | * Fast allocation side cache array/stack |
27 | * |
28 | * The cache size and refill watermark is related to the network |
29 | * use-case. The NAPI budget is 64 packets. After a NAPI poll the RX |
30 | * ring is usually refilled and the max consumed elements will be 64, |
31 | * thus a natural max size of objects needed in the cache. |
32 | * |
33 | * Keeping room for more objects, is due to XDP_DROP use-case. As |
34 | * XDP_DROP allows the opportunity to recycle objects directly into |
35 | * this array, as it shares the same softirq/NAPI protection. If |
36 | * cache is already full (or partly full) then the XDP_DROP recycles |
37 | * would have to take a slower code path. |
38 | */ |
39 | #define PP_ALLOC_CACHE_SIZE 128 |
40 | #define PP_ALLOC_CACHE_REFILL 64 |
41 | struct pp_alloc_cache { |
42 | u32 count; |
43 | struct page *cache[PP_ALLOC_CACHE_SIZE]; |
44 | }; |
45 | |
46 | /** |
47 | * struct page_pool_params - page pool parameters |
48 | * @flags: PP_FLAG_DMA_MAP, PP_FLAG_DMA_SYNC_DEV |
49 | * @order: 2^order pages on allocation |
50 | * @pool_size: size of the ptr_ring |
51 | * @nid: NUMA node id to allocate from pages from |
52 | * @dev: device, for DMA pre-mapping purposes |
53 | * @netdev: netdev this pool will serve (leave as NULL if none or multiple) |
54 | * @napi: NAPI which is the sole consumer of pages, otherwise NULL |
55 | * @dma_dir: DMA mapping direction |
56 | * @max_len: max DMA sync memory size for PP_FLAG_DMA_SYNC_DEV |
57 | * @offset: DMA sync address offset for PP_FLAG_DMA_SYNC_DEV |
58 | */ |
59 | struct page_pool_params { |
60 | struct_group_tagged(page_pool_params_fast, fast, |
61 | unsigned int flags; |
62 | unsigned int order; |
63 | unsigned int pool_size; |
64 | int nid; |
65 | struct device *dev; |
66 | struct napi_struct *napi; |
67 | enum dma_data_direction dma_dir; |
68 | unsigned int max_len; |
69 | unsigned int offset; |
70 | ); |
71 | struct_group_tagged(page_pool_params_slow, slow, |
72 | struct net_device *netdev; |
73 | /* private: used by test code only */ |
74 | void (*init_callback)(struct page *page, void *arg); |
75 | void *init_arg; |
76 | ); |
77 | }; |
78 | |
79 | #ifdef CONFIG_PAGE_POOL_STATS |
80 | /** |
81 | * struct page_pool_alloc_stats - allocation statistics |
82 | * @fast: successful fast path allocations |
83 | * @slow: slow path order-0 allocations |
84 | * @slow_high_order: slow path high order allocations |
85 | * @empty: ptr ring is empty, so a slow path allocation was forced |
86 | * @refill: an allocation which triggered a refill of the cache |
87 | * @waive: pages obtained from the ptr ring that cannot be added to |
88 | * the cache due to a NUMA mismatch |
89 | */ |
90 | struct page_pool_alloc_stats { |
91 | u64 fast; |
92 | u64 slow; |
93 | u64 slow_high_order; |
94 | u64 empty; |
95 | u64 refill; |
96 | u64 waive; |
97 | }; |
98 | |
99 | /** |
100 | * struct page_pool_recycle_stats - recycling (freeing) statistics |
101 | * @cached: recycling placed page in the page pool cache |
102 | * @cache_full: page pool cache was full |
103 | * @ring: page placed into the ptr ring |
104 | * @ring_full: page released from page pool because the ptr ring was full |
105 | * @released_refcnt: page released (and not recycled) because refcnt > 1 |
106 | */ |
107 | struct page_pool_recycle_stats { |
108 | u64 cached; |
109 | u64 cache_full; |
110 | u64 ring; |
111 | u64 ring_full; |
112 | u64 released_refcnt; |
113 | }; |
114 | |
115 | /** |
116 | * struct page_pool_stats - combined page pool use statistics |
117 | * @alloc_stats: see struct page_pool_alloc_stats |
118 | * @recycle_stats: see struct page_pool_recycle_stats |
119 | * |
120 | * Wrapper struct for combining page pool stats with different storage |
121 | * requirements. |
122 | */ |
123 | struct page_pool_stats { |
124 | struct page_pool_alloc_stats alloc_stats; |
125 | struct page_pool_recycle_stats recycle_stats; |
126 | }; |
127 | #endif |
128 | |
129 | struct page_pool { |
130 | struct page_pool_params_fast p; |
131 | |
132 | int cpuid; |
133 | bool has_init_callback; |
134 | |
135 | long frag_users; |
136 | struct page *frag_page; |
137 | unsigned int frag_offset; |
138 | u32 pages_state_hold_cnt; |
139 | |
140 | struct delayed_work release_dw; |
141 | void (*disconnect)(void *pool); |
142 | unsigned long defer_start; |
143 | unsigned long defer_warn; |
144 | |
145 | #ifdef CONFIG_PAGE_POOL_STATS |
146 | /* these stats are incremented while in softirq context */ |
147 | struct page_pool_alloc_stats alloc_stats; |
148 | #endif |
149 | u32 xdp_mem_id; |
150 | |
151 | /* |
152 | * Data structure for allocation side |
153 | * |
154 | * Drivers allocation side usually already perform some kind |
155 | * of resource protection. Piggyback on this protection, and |
156 | * require driver to protect allocation side. |
157 | * |
158 | * For NIC drivers this means, allocate a page_pool per |
159 | * RX-queue. As the RX-queue is already protected by |
160 | * Softirq/BH scheduling and napi_schedule. NAPI schedule |
161 | * guarantee that a single napi_struct will only be scheduled |
162 | * on a single CPU (see napi_schedule). |
163 | */ |
164 | struct pp_alloc_cache alloc ____cacheline_aligned_in_smp; |
165 | |
166 | /* Data structure for storing recycled pages. |
167 | * |
168 | * Returning/freeing pages is more complicated synchronization |
169 | * wise, because free's can happen on remote CPUs, with no |
170 | * association with allocation resource. |
171 | * |
172 | * Use ptr_ring, as it separates consumer and producer |
173 | * efficiently, it a way that doesn't bounce cache-lines. |
174 | * |
175 | * TODO: Implement bulk return pages into this structure. |
176 | */ |
177 | struct ptr_ring ring; |
178 | |
179 | #ifdef CONFIG_PAGE_POOL_STATS |
180 | /* recycle stats are per-cpu to avoid locking */ |
181 | struct page_pool_recycle_stats __percpu *recycle_stats; |
182 | #endif |
183 | atomic_t pages_state_release_cnt; |
184 | |
185 | /* A page_pool is strictly tied to a single RX-queue being |
186 | * protected by NAPI, due to above pp_alloc_cache. This |
187 | * refcnt serves purpose is to simplify drivers error handling. |
188 | */ |
189 | refcount_t user_cnt; |
190 | |
191 | u64 destroy_cnt; |
192 | |
193 | /* Slow/Control-path information follows */ |
194 | struct page_pool_params_slow slow; |
195 | /* User-facing fields, protected by page_pools_lock */ |
196 | struct { |
197 | struct hlist_node list; |
198 | u64 detach_time; |
199 | u32 napi_id; |
200 | u32 id; |
201 | } user; |
202 | }; |
203 | |
204 | struct page *page_pool_alloc_pages(struct page_pool *pool, gfp_t gfp); |
205 | struct page *page_pool_alloc_frag(struct page_pool *pool, unsigned int *offset, |
206 | unsigned int size, gfp_t gfp); |
207 | struct page_pool *page_pool_create(const struct page_pool_params *params); |
208 | struct page_pool *page_pool_create_percpu(const struct page_pool_params *params, |
209 | int cpuid); |
210 | |
211 | struct xdp_mem_info; |
212 | |
213 | #ifdef CONFIG_PAGE_POOL |
214 | void page_pool_destroy(struct page_pool *pool); |
215 | void page_pool_use_xdp_mem(struct page_pool *pool, void (*disconnect)(void *), |
216 | struct xdp_mem_info *mem); |
217 | void page_pool_put_page_bulk(struct page_pool *pool, void **data, |
218 | int count); |
219 | #else |
220 | static inline void page_pool_destroy(struct page_pool *pool) |
221 | { |
222 | } |
223 | |
224 | static inline void page_pool_use_xdp_mem(struct page_pool *pool, |
225 | void (*disconnect)(void *), |
226 | struct xdp_mem_info *mem) |
227 | { |
228 | } |
229 | |
230 | static inline void page_pool_put_page_bulk(struct page_pool *pool, void **data, |
231 | int count) |
232 | { |
233 | } |
234 | #endif |
235 | |
236 | void page_pool_put_unrefed_page(struct page_pool *pool, struct page *page, |
237 | unsigned int dma_sync_size, |
238 | bool allow_direct); |
239 | |
240 | static inline bool is_page_pool_compiled_in(void) |
241 | { |
242 | #ifdef CONFIG_PAGE_POOL |
243 | return true; |
244 | #else |
245 | return false; |
246 | #endif |
247 | } |
248 | |
249 | /* Caller must provide appropriate safe context, e.g. NAPI. */ |
250 | void page_pool_update_nid(struct page_pool *pool, int new_nid); |
251 | |
252 | #endif /* _NET_PAGE_POOL_H */ |
253 | |