1 /* SPDX-License-Identifier: GPL-2.0 */
5 #include <linux/blkdev.h>
6 #include <linux/sbitmap.h>
7 #include <linux/srcu.h>
10 struct blk_flush_queue;
12 struct blk_mq_hw_ctx {
15 struct list_head dispatch;
16 unsigned long state; /* BLK_MQ_S_* flags */
17 } ____cacheline_aligned_in_smp;
19 struct delayed_work run_work;
20 cpumask_var_t cpumask;
24 unsigned long flags; /* BLK_MQ_F_* flags */
27 struct request_queue *queue;
28 struct blk_flush_queue *fq;
32 struct sbitmap ctx_map;
34 struct blk_mq_ctx *dispatch_from;
36 struct blk_mq_ctx **ctxs;
39 wait_queue_entry_t dispatch_wait;
42 struct blk_mq_tags *tags;
43 struct blk_mq_tags *sched_tags;
47 #define BLK_MQ_MAX_DISPATCH_ORDER 7
48 unsigned long dispatched[BLK_MQ_MAX_DISPATCH_ORDER];
50 unsigned int numa_node;
51 unsigned int queue_num;
55 struct hlist_node cpuhp_dead;
58 unsigned long poll_considered;
59 unsigned long poll_invoked;
60 unsigned long poll_success;
62 #ifdef CONFIG_BLK_DEBUG_FS
63 struct dentry *debugfs_dir;
64 struct dentry *sched_debugfs_dir;
67 /* Must be the last member - see also blk_mq_hw_ctx_size(). */
68 struct srcu_struct queue_rq_srcu[0];
71 struct blk_mq_tag_set {
73 const struct blk_mq_ops *ops;
74 unsigned int nr_hw_queues;
75 unsigned int queue_depth; /* max hw supported */
76 unsigned int reserved_tags;
77 unsigned int cmd_size; /* per-request extra data */
80 unsigned int flags; /* BLK_MQ_F_* */
83 struct blk_mq_tags **tags;
85 struct mutex tag_list_lock;
86 struct list_head tag_list;
89 struct blk_mq_queue_data {
94 typedef blk_status_t (queue_rq_fn)(struct blk_mq_hw_ctx *,
95 const struct blk_mq_queue_data *);
96 typedef bool (get_budget_fn)(struct blk_mq_hw_ctx *);
97 typedef void (put_budget_fn)(struct blk_mq_hw_ctx *);
98 typedef enum blk_eh_timer_return (timeout_fn)(struct request *, bool);
99 typedef int (init_hctx_fn)(struct blk_mq_hw_ctx *, void *, unsigned int);
100 typedef void (exit_hctx_fn)(struct blk_mq_hw_ctx *, unsigned int);
101 typedef int (init_request_fn)(struct blk_mq_tag_set *set, struct request *,
102 unsigned int, unsigned int);
103 typedef void (exit_request_fn)(struct blk_mq_tag_set *set, struct request *,
106 typedef void (busy_iter_fn)(struct blk_mq_hw_ctx *, struct request *, void *,
108 typedef void (busy_tag_iter_fn)(struct request *, void *, bool);
109 typedef int (poll_fn)(struct blk_mq_hw_ctx *, unsigned int);
110 typedef int (map_queues_fn)(struct blk_mq_tag_set *set);
117 queue_rq_fn *queue_rq;
120 * Reserve budget before queue request, once .queue_rq is
121 * run, it is driver's responsibility to release the
122 * reserved budget. Also we have to handle failure case
123 * of .get_budget for avoiding I/O deadlock.
125 get_budget_fn *get_budget;
126 put_budget_fn *put_budget;
129 * Called on request timeout
134 * Called to poll for completion of a specific tag.
138 softirq_done_fn *complete;
141 * Called when the block layer side of a hardware queue has been
142 * set up, allowing the driver to allocate/init matching structures.
143 * Ditto for exit/teardown.
145 init_hctx_fn *init_hctx;
146 exit_hctx_fn *exit_hctx;
149 * Called for every command allocated by the block layer to allow
150 * the driver to set up driver specific data.
152 * Tag greater than or equal to queue_depth is for setting up
155 * Ditto for exit/teardown.
157 init_request_fn *init_request;
158 exit_request_fn *exit_request;
159 /* Called from inside blk_get_request() */
160 void (*initialize_rq_fn)(struct request *rq);
162 map_queues_fn *map_queues;
164 #ifdef CONFIG_BLK_DEBUG_FS
166 * Used by the debugfs implementation to show driver-specific
167 * information about a request.
169 void (*show_rq)(struct seq_file *m, struct request *rq);
174 BLK_MQ_F_SHOULD_MERGE = 1 << 0,
175 BLK_MQ_F_TAG_SHARED = 1 << 1,
176 BLK_MQ_F_SG_MERGE = 1 << 2,
177 BLK_MQ_F_BLOCKING = 1 << 5,
178 BLK_MQ_F_NO_SCHED = 1 << 6,
179 BLK_MQ_F_ALLOC_POLICY_START_BIT = 8,
180 BLK_MQ_F_ALLOC_POLICY_BITS = 1,
182 BLK_MQ_S_STOPPED = 0,
183 BLK_MQ_S_TAG_ACTIVE = 1,
184 BLK_MQ_S_SCHED_RESTART = 2,
185 BLK_MQ_S_START_ON_RUN = 3,
187 BLK_MQ_MAX_DEPTH = 10240,
189 BLK_MQ_CPU_WORK_BATCH = 8,
191 #define BLK_MQ_FLAG_TO_ALLOC_POLICY(flags) \
192 ((flags >> BLK_MQ_F_ALLOC_POLICY_START_BIT) & \
193 ((1 << BLK_MQ_F_ALLOC_POLICY_BITS) - 1))
194 #define BLK_ALLOC_POLICY_TO_MQ_FLAG(policy) \
195 ((policy & ((1 << BLK_MQ_F_ALLOC_POLICY_BITS) - 1)) \
196 << BLK_MQ_F_ALLOC_POLICY_START_BIT)
198 struct request_queue *blk_mq_init_queue(struct blk_mq_tag_set *);
199 struct request_queue *blk_mq_init_allocated_queue(struct blk_mq_tag_set *set,
200 struct request_queue *q);
201 int blk_mq_register_dev(struct device *, struct request_queue *);
202 void blk_mq_unregister_dev(struct device *, struct request_queue *);
204 int blk_mq_alloc_tag_set(struct blk_mq_tag_set *set);
205 void blk_mq_free_tag_set(struct blk_mq_tag_set *set);
207 void blk_mq_flush_plug_list(struct blk_plug *plug, bool from_schedule);
209 void blk_mq_free_request(struct request *rq);
210 bool blk_mq_can_queue(struct blk_mq_hw_ctx *);
213 /* return when out of requests */
214 BLK_MQ_REQ_NOWAIT = (__force blk_mq_req_flags_t)(1 << 0),
215 /* allocate from reserved pool */
216 BLK_MQ_REQ_RESERVED = (__force blk_mq_req_flags_t)(1 << 1),
217 /* allocate internal/sched tag */
218 BLK_MQ_REQ_INTERNAL = (__force blk_mq_req_flags_t)(1 << 2),
219 /* set RQF_PREEMPT */
220 BLK_MQ_REQ_PREEMPT = (__force blk_mq_req_flags_t)(1 << 3),
223 struct request *blk_mq_alloc_request(struct request_queue *q, unsigned int op,
224 blk_mq_req_flags_t flags);
225 struct request *blk_mq_alloc_request_hctx(struct request_queue *q,
226 unsigned int op, blk_mq_req_flags_t flags,
227 unsigned int hctx_idx);
228 struct request *blk_mq_tag_to_rq(struct blk_mq_tags *tags, unsigned int tag);
231 BLK_MQ_UNIQUE_TAG_BITS = 16,
232 BLK_MQ_UNIQUE_TAG_MASK = (1 << BLK_MQ_UNIQUE_TAG_BITS) - 1,
235 u32 blk_mq_unique_tag(struct request *rq);
237 static inline u16 blk_mq_unique_tag_to_hwq(u32 unique_tag)
239 return unique_tag >> BLK_MQ_UNIQUE_TAG_BITS;
242 static inline u16 blk_mq_unique_tag_to_tag(u32 unique_tag)
244 return unique_tag & BLK_MQ_UNIQUE_TAG_MASK;
248 int blk_mq_request_started(struct request *rq);
249 void blk_mq_start_request(struct request *rq);
250 void blk_mq_end_request(struct request *rq, blk_status_t error);
251 void __blk_mq_end_request(struct request *rq, blk_status_t error);
253 void blk_mq_requeue_request(struct request *rq, bool kick_requeue_list);
254 void blk_mq_add_to_requeue_list(struct request *rq, bool at_head,
255 bool kick_requeue_list);
256 void blk_mq_kick_requeue_list(struct request_queue *q);
257 void blk_mq_delay_kick_requeue_list(struct request_queue *q, unsigned long msecs);
258 void blk_mq_complete_request(struct request *rq);
260 bool blk_mq_queue_stopped(struct request_queue *q);
261 void blk_mq_stop_hw_queue(struct blk_mq_hw_ctx *hctx);
262 void blk_mq_start_hw_queue(struct blk_mq_hw_ctx *hctx);
263 void blk_mq_stop_hw_queues(struct request_queue *q);
264 void blk_mq_start_hw_queues(struct request_queue *q);
265 void blk_mq_start_stopped_hw_queue(struct blk_mq_hw_ctx *hctx, bool async);
266 void blk_mq_start_stopped_hw_queues(struct request_queue *q, bool async);
267 void blk_mq_quiesce_queue(struct request_queue *q);
268 void blk_mq_unquiesce_queue(struct request_queue *q);
269 void blk_mq_delay_run_hw_queue(struct blk_mq_hw_ctx *hctx, unsigned long msecs);
270 bool blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx, bool async);
271 void blk_mq_run_hw_queues(struct request_queue *q, bool async);
272 void blk_mq_delay_queue(struct blk_mq_hw_ctx *hctx, unsigned long msecs);
273 void blk_mq_tagset_busy_iter(struct blk_mq_tag_set *tagset,
274 busy_tag_iter_fn *fn, void *priv);
275 void blk_mq_freeze_queue(struct request_queue *q);
276 void blk_mq_unfreeze_queue(struct request_queue *q);
277 void blk_freeze_queue_start(struct request_queue *q);
278 void blk_mq_freeze_queue_wait(struct request_queue *q);
279 int blk_mq_freeze_queue_wait_timeout(struct request_queue *q,
280 unsigned long timeout);
281 int blk_mq_tagset_iter(struct blk_mq_tag_set *set, void *data,
282 int (reinit_request)(void *, struct request *));
284 int blk_mq_map_queues(struct blk_mq_tag_set *set);
285 void blk_mq_update_nr_hw_queues(struct blk_mq_tag_set *set, int nr_hw_queues);
287 void blk_mq_quiesce_queue_nowait(struct request_queue *q);
290 * Driver command data is immediately after the request. So subtract request
291 * size to get back to the original request, add request size to get the PDU.
293 static inline struct request *blk_mq_rq_from_pdu(void *pdu)
295 return pdu - sizeof(struct request);
297 static inline void *blk_mq_rq_to_pdu(struct request *rq)
302 #define queue_for_each_hw_ctx(q, hctx, i) \
303 for ((i) = 0; (i) < (q)->nr_hw_queues && \
304 ({ hctx = (q)->queue_hw_ctx[i]; 1; }); (i)++)
306 #define hctx_for_each_ctx(hctx, ctx, i) \
307 for ((i) = 0; (i) < (hctx)->nr_ctx && \
308 ({ ctx = (hctx)->ctxs[(i)]; 1; }); (i)++)