Commit | Line | Data |
---|---|---|
672fdcf0 ML |
1 | /* SPDX-License-Identifier: GPL-2.0 */ |
2 | #ifndef _BLK_CGROUP_PRIVATE_H | |
3 | #define _BLK_CGROUP_PRIVATE_H | |
4 | /* | |
5 | * block cgroup private header | |
6 | * | |
7 | * Based on ideas and code from CFQ, CFS and BFQ: | |
8 | * Copyright (C) 2003 Jens Axboe <axboe@kernel.dk> | |
9 | * | |
10 | * Copyright (C) 2008 Fabio Checconi <fabio@gandalf.sssup.it> | |
11 | * Paolo Valente <paolo.valente@unimore.it> | |
12 | * | |
13 | * Copyright (C) 2009 Vivek Goyal <vgoyal@redhat.com> | |
14 | * Nauman Rafique <nauman@google.com> | |
15 | */ | |
16 | ||
17 | #include <linux/blk-cgroup.h> | |
c97ab271 CH |
18 | #include <linux/cgroup.h> |
19 | #include <linux/kthread.h> | |
6b2b0459 | 20 | #include <linux/blk-mq.h> |
3b8cc629 | 21 | #include <linux/llist.h> |
672fdcf0 | 22 | |
dec223c9 CH |
23 | struct blkcg_gq; |
24 | struct blkg_policy_data; | |
25 | ||
26 | ||
672fdcf0 ML |
27 | /* percpu_counter batch for blkg_[rw]stats, per-cpu drift doesn't matter */ |
28 | #define BLKG_STAT_CPU_BATCH (INT_MAX / 2) | |
29 | ||
30 | #ifdef CONFIG_BLK_CGROUP | |
bbb1ebe7 CH |
31 | |
32 | enum blkg_iostat_type { | |
33 | BLKG_IOSTAT_READ, | |
34 | BLKG_IOSTAT_WRITE, | |
35 | BLKG_IOSTAT_DISCARD, | |
36 | ||
37 | BLKG_IOSTAT_NR, | |
38 | }; | |
39 | ||
40 | struct blkg_iostat { | |
41 | u64 bytes[BLKG_IOSTAT_NR]; | |
42 | u64 ios[BLKG_IOSTAT_NR]; | |
43 | }; | |
44 | ||
45 | struct blkg_iostat_set { | |
46 | struct u64_stats_sync sync; | |
3b8cc629 WL |
47 | struct blkcg_gq *blkg; |
48 | struct llist_node lnode; | |
49 | int lqueued; /* queued in llist */ | |
bbb1ebe7 CH |
50 | struct blkg_iostat cur; |
51 | struct blkg_iostat last; | |
52 | }; | |
53 | ||
54 | /* association between a blk cgroup and a request queue */ | |
55 | struct blkcg_gq { | |
a06377c5 CH |
56 | /* Pointer to the associated request_queue */ |
57 | struct request_queue *q; | |
1231039d | 58 | struct list_head q_node; |
bbb1ebe7 CH |
59 | struct hlist_node blkcg_node; |
60 | struct blkcg *blkcg; | |
61 | ||
62 | /* all non-root blkcg_gq's are guaranteed to have access to parent */ | |
63 | struct blkcg_gq *parent; | |
64 | ||
65 | /* reference count */ | |
66 | struct percpu_ref refcnt; | |
67 | ||
68 | /* is this blkg online? protected by both blkcg and q locks */ | |
69 | bool online; | |
70 | ||
71 | struct blkg_iostat_set __percpu *iostat_cpu; | |
72 | struct blkg_iostat_set iostat; | |
73 | ||
74 | struct blkg_policy_data *pd[BLKCG_MAX_POLS]; | |
2c275afe | 75 | #ifdef CONFIG_BLK_CGROUP_PUNT_BIO |
bbb1ebe7 CH |
76 | spinlock_t async_bio_lock; |
77 | struct bio_list async_bios; | |
2c275afe | 78 | #endif |
bbb1ebe7 CH |
79 | union { |
80 | struct work_struct async_bio_work; | |
81 | struct work_struct free_work; | |
82 | }; | |
83 | ||
84 | atomic_t use_delay; | |
85 | atomic64_t delay_nsec; | |
86 | atomic64_t delay_start; | |
87 | u64 last_delay; | |
88 | int last_use; | |
89 | ||
90 | struct rcu_head rcu_head; | |
91 | }; | |
92 | ||
dec223c9 CH |
93 | struct blkcg { |
94 | struct cgroup_subsys_state css; | |
95 | spinlock_t lock; | |
96 | refcount_t online_pin; | |
97 | ||
98 | struct radix_tree_root blkg_tree; | |
99 | struct blkcg_gq __rcu *blkg_hint; | |
100 | struct hlist_head blkg_list; | |
101 | ||
102 | struct blkcg_policy_data *cpd[BLKCG_MAX_POLS]; | |
103 | ||
104 | struct list_head all_blkcgs_node; | |
3b8cc629 WL |
105 | |
106 | /* | |
107 | * List of updated percpu blkg_iostat_set's since the last flush. | |
108 | */ | |
109 | struct llist_head __percpu *lhead; | |
110 | ||
dec223c9 CH |
111 | #ifdef CONFIG_BLK_CGROUP_FC_APPID |
112 | char fc_app_id[FC_APPID_LEN]; | |
113 | #endif | |
114 | #ifdef CONFIG_CGROUP_WRITEBACK | |
115 | struct list_head cgwb_list; | |
116 | #endif | |
117 | }; | |
118 | ||
119 | static inline struct blkcg *css_to_blkcg(struct cgroup_subsys_state *css) | |
120 | { | |
121 | return css ? container_of(css, struct blkcg, css) : NULL; | |
122 | } | |
672fdcf0 ML |
123 | |
124 | /* | |
125 | * A blkcg_gq (blkg) is association between a block cgroup (blkcg) and a | |
126 | * request_queue (q). This is used by blkcg policies which need to track | |
127 | * information per blkcg - q pair. | |
128 | * | |
129 | * There can be multiple active blkcg policies and each blkg:policy pair is | |
130 | * represented by a blkg_policy_data which is allocated and freed by each | |
131 | * policy's pd_alloc/free_fn() methods. A policy can allocate private data | |
132 | * area by allocating larger data structure which embeds blkg_policy_data | |
133 | * at the beginning. | |
134 | */ | |
135 | struct blkg_policy_data { | |
136 | /* the blkg and policy id this per-policy data belongs to */ | |
137 | struct blkcg_gq *blkg; | |
138 | int plid; | |
dfd6200a | 139 | bool online; |
672fdcf0 ML |
140 | }; |
141 | ||
142 | /* | |
143 | * Policies that need to keep per-blkcg data which is independent from any | |
144 | * request_queue associated to it should implement cpd_alloc/free_fn() | |
145 | * methods. A policy can allocate private data area by allocating larger | |
146 | * data structure which embeds blkcg_policy_data at the beginning. | |
147 | * cpd_init() is invoked to let each policy handle per-blkcg data. | |
148 | */ | |
149 | struct blkcg_policy_data { | |
150 | /* the blkcg and policy id this per-policy data belongs to */ | |
151 | struct blkcg *blkcg; | |
152 | int plid; | |
153 | }; | |
154 | ||
155 | typedef struct blkcg_policy_data *(blkcg_pol_alloc_cpd_fn)(gfp_t gfp); | |
156 | typedef void (blkcg_pol_init_cpd_fn)(struct blkcg_policy_data *cpd); | |
157 | typedef void (blkcg_pol_free_cpd_fn)(struct blkcg_policy_data *cpd); | |
158 | typedef void (blkcg_pol_bind_cpd_fn)(struct blkcg_policy_data *cpd); | |
0a0b4f79 CH |
159 | typedef struct blkg_policy_data *(blkcg_pol_alloc_pd_fn)(struct gendisk *disk, |
160 | struct blkcg *blkcg, gfp_t gfp); | |
672fdcf0 ML |
161 | typedef void (blkcg_pol_init_pd_fn)(struct blkg_policy_data *pd); |
162 | typedef void (blkcg_pol_online_pd_fn)(struct blkg_policy_data *pd); | |
163 | typedef void (blkcg_pol_offline_pd_fn)(struct blkg_policy_data *pd); | |
164 | typedef void (blkcg_pol_free_pd_fn)(struct blkg_policy_data *pd); | |
165 | typedef void (blkcg_pol_reset_pd_stats_fn)(struct blkg_policy_data *pd); | |
3607849d | 166 | typedef void (blkcg_pol_stat_pd_fn)(struct blkg_policy_data *pd, |
672fdcf0 ML |
167 | struct seq_file *s); |
168 | ||
169 | struct blkcg_policy { | |
170 | int plid; | |
171 | /* cgroup files for the policy */ | |
172 | struct cftype *dfl_cftypes; | |
173 | struct cftype *legacy_cftypes; | |
174 | ||
175 | /* operations */ | |
176 | blkcg_pol_alloc_cpd_fn *cpd_alloc_fn; | |
672fdcf0 | 177 | blkcg_pol_free_cpd_fn *cpd_free_fn; |
672fdcf0 ML |
178 | |
179 | blkcg_pol_alloc_pd_fn *pd_alloc_fn; | |
180 | blkcg_pol_init_pd_fn *pd_init_fn; | |
181 | blkcg_pol_online_pd_fn *pd_online_fn; | |
182 | blkcg_pol_offline_pd_fn *pd_offline_fn; | |
183 | blkcg_pol_free_pd_fn *pd_free_fn; | |
184 | blkcg_pol_reset_pd_stats_fn *pd_reset_stats_fn; | |
185 | blkcg_pol_stat_pd_fn *pd_stat_fn; | |
186 | }; | |
187 | ||
188 | extern struct blkcg blkcg_root; | |
189 | extern bool blkcg_debug_stats; | |
190 | ||
9823538f CH |
191 | int blkcg_init_disk(struct gendisk *disk); |
192 | void blkcg_exit_disk(struct gendisk *disk); | |
672fdcf0 ML |
193 | |
194 | /* Blkio controller policy registration */ | |
195 | int blkcg_policy_register(struct blkcg_policy *pol); | |
196 | void blkcg_policy_unregister(struct blkcg_policy *pol); | |
40e4996e CH |
197 | int blkcg_activate_policy(struct gendisk *disk, const struct blkcg_policy *pol); |
198 | void blkcg_deactivate_policy(struct gendisk *disk, | |
672fdcf0 ML |
199 | const struct blkcg_policy *pol); |
200 | ||
201 | const char *blkg_dev_name(struct blkcg_gq *blkg); | |
202 | void blkcg_print_blkgs(struct seq_file *sf, struct blkcg *blkcg, | |
203 | u64 (*prfill)(struct seq_file *, | |
204 | struct blkg_policy_data *, int), | |
205 | const struct blkcg_policy *pol, int data, | |
206 | bool show_total); | |
207 | u64 __blkg_prfill_u64(struct seq_file *sf, struct blkg_policy_data *pd, u64 v); | |
208 | ||
209 | struct blkg_conf_ctx { | |
faffaab2 TH |
210 | char *input; |
211 | char *body; | |
672fdcf0 ML |
212 | struct block_device *bdev; |
213 | struct blkcg_gq *blkg; | |
672fdcf0 ML |
214 | }; |
215 | ||
faffaab2 TH |
216 | void blkg_conf_init(struct blkg_conf_ctx *ctx, char *input); |
217 | int blkg_conf_open_bdev(struct blkg_conf_ctx *ctx); | |
672fdcf0 | 218 | int blkg_conf_prep(struct blkcg *blkcg, const struct blkcg_policy *pol, |
faffaab2 TH |
219 | struct blkg_conf_ctx *ctx); |
220 | void blkg_conf_exit(struct blkg_conf_ctx *ctx); | |
672fdcf0 | 221 | |
672fdcf0 ML |
222 | /** |
223 | * bio_issue_as_root_blkg - see if this bio needs to be issued as root blkg | |
224 | * @return: true if this bio needs to be submitted with the root blkg context. | |
225 | * | |
226 | * In order to avoid priority inversions we sometimes need to issue a bio as if | |
227 | * it were attached to the root blkg, and then backcharge to the actual owning | |
bbb1ebe7 CH |
228 | * blkg. The idea is we do bio_blkcg_css() to look up the actual context for |
229 | * the bio and attach the appropriate blkg to the bio. Then we call this helper | |
230 | * and if it is true run with the root blkg for that queue and then do any | |
672fdcf0 ML |
231 | * backcharging to the originating cgroup once the io is complete. |
232 | */ | |
233 | static inline bool bio_issue_as_root_blkg(struct bio *bio) | |
234 | { | |
235 | return (bio->bi_opf & (REQ_META | REQ_SWAP)) != 0; | |
236 | } | |
237 | ||
238 | /** | |
9a9c261e | 239 | * blkg_lookup - lookup blkg for the specified blkcg - q pair |
672fdcf0 | 240 | * @blkcg: blkcg of interest |
9a9c261e | 241 | * @q: request_queue of interest |
672fdcf0 | 242 | * |
9a9c261e | 243 | * Lookup blkg for the @blkcg - @q pair. |
4a69f325 CH |
244 | |
245 | * Must be called in a RCU critical section. | |
672fdcf0 | 246 | */ |
4a69f325 | 247 | static inline struct blkcg_gq *blkg_lookup(struct blkcg *blkcg, |
9a9c261e | 248 | struct request_queue *q) |
672fdcf0 ML |
249 | { |
250 | struct blkcg_gq *blkg; | |
251 | ||
4a69f325 CH |
252 | WARN_ON_ONCE(!rcu_read_lock_held()); |
253 | ||
672fdcf0 | 254 | if (blkcg == &blkcg_root) |
9a9c261e | 255 | return q->root_blkg; |
672fdcf0 ML |
256 | |
257 | blkg = rcu_dereference(blkcg->blkg_hint); | |
a06377c5 | 258 | if (blkg && blkg->q == q) |
672fdcf0 ML |
259 | return blkg; |
260 | ||
9a9c261e | 261 | blkg = radix_tree_lookup(&blkcg->blkg_tree, q->id); |
a06377c5 | 262 | if (blkg && blkg->q != q) |
4a69f325 CH |
263 | blkg = NULL; |
264 | return blkg; | |
672fdcf0 ML |
265 | } |
266 | ||
672fdcf0 ML |
267 | /** |
268 | * blkg_to_pdata - get policy private data | |
269 | * @blkg: blkg of interest | |
270 | * @pol: policy of interest | |
271 | * | |
272 | * Return pointer to private data associated with the @blkg-@pol pair. | |
273 | */ | |
274 | static inline struct blkg_policy_data *blkg_to_pd(struct blkcg_gq *blkg, | |
275 | struct blkcg_policy *pol) | |
276 | { | |
277 | return blkg ? blkg->pd[pol->plid] : NULL; | |
278 | } | |
279 | ||
280 | static inline struct blkcg_policy_data *blkcg_to_cpd(struct blkcg *blkcg, | |
281 | struct blkcg_policy *pol) | |
282 | { | |
283 | return blkcg ? blkcg->cpd[pol->plid] : NULL; | |
284 | } | |
285 | ||
286 | /** | |
287 | * pdata_to_blkg - get blkg associated with policy private data | |
288 | * @pd: policy private data of interest | |
289 | * | |
290 | * @pd is policy private data. Determine the blkg it's associated with. | |
291 | */ | |
292 | static inline struct blkcg_gq *pd_to_blkg(struct blkg_policy_data *pd) | |
293 | { | |
294 | return pd ? pd->blkg : NULL; | |
295 | } | |
296 | ||
297 | static inline struct blkcg *cpd_to_blkcg(struct blkcg_policy_data *cpd) | |
298 | { | |
299 | return cpd ? cpd->blkcg : NULL; | |
300 | } | |
301 | ||
302 | /** | |
303 | * blkg_path - format cgroup path of blkg | |
304 | * @blkg: blkg of interest | |
305 | * @buf: target buffer | |
306 | * @buflen: target buffer length | |
307 | * | |
308 | * Format the path of the cgroup of @blkg into @buf. | |
309 | */ | |
310 | static inline int blkg_path(struct blkcg_gq *blkg, char *buf, int buflen) | |
311 | { | |
312 | return cgroup_path(blkg->blkcg->css.cgroup, buf, buflen); | |
313 | } | |
314 | ||
315 | /** | |
316 | * blkg_get - get a blkg reference | |
317 | * @blkg: blkg to get | |
318 | * | |
319 | * The caller should be holding an existing reference. | |
320 | */ | |
321 | static inline void blkg_get(struct blkcg_gq *blkg) | |
322 | { | |
323 | percpu_ref_get(&blkg->refcnt); | |
324 | } | |
325 | ||
326 | /** | |
327 | * blkg_tryget - try and get a blkg reference | |
328 | * @blkg: blkg to get | |
329 | * | |
330 | * This is for use when doing an RCU lookup of the blkg. We may be in the midst | |
331 | * of freeing this blkg, so we can only use it if the refcnt is not zero. | |
332 | */ | |
333 | static inline bool blkg_tryget(struct blkcg_gq *blkg) | |
334 | { | |
335 | return blkg && percpu_ref_tryget(&blkg->refcnt); | |
336 | } | |
337 | ||
338 | /** | |
339 | * blkg_put - put a blkg reference | |
340 | * @blkg: blkg to put | |
341 | */ | |
342 | static inline void blkg_put(struct blkcg_gq *blkg) | |
343 | { | |
344 | percpu_ref_put(&blkg->refcnt); | |
345 | } | |
346 | ||
347 | /** | |
348 | * blkg_for_each_descendant_pre - pre-order walk of a blkg's descendants | |
349 | * @d_blkg: loop cursor pointing to the current descendant | |
350 | * @pos_css: used for iteration | |
351 | * @p_blkg: target blkg to walk descendants of | |
352 | * | |
353 | * Walk @c_blkg through the descendants of @p_blkg. Must be used with RCU | |
354 | * read locked. If called under either blkcg or queue lock, the iteration | |
355 | * is guaranteed to include all and only online blkgs. The caller may | |
356 | * update @pos_css by calling css_rightmost_descendant() to skip subtree. | |
357 | * @p_blkg is included in the iteration and the first node to be visited. | |
358 | */ | |
359 | #define blkg_for_each_descendant_pre(d_blkg, pos_css, p_blkg) \ | |
360 | css_for_each_descendant_pre((pos_css), &(p_blkg)->blkcg->css) \ | |
79fcc5be | 361 | if (((d_blkg) = blkg_lookup(css_to_blkcg(pos_css), \ |
a06377c5 | 362 | (p_blkg)->q))) |
672fdcf0 ML |
363 | |
364 | /** | |
365 | * blkg_for_each_descendant_post - post-order walk of a blkg's descendants | |
366 | * @d_blkg: loop cursor pointing to the current descendant | |
367 | * @pos_css: used for iteration | |
368 | * @p_blkg: target blkg to walk descendants of | |
369 | * | |
370 | * Similar to blkg_for_each_descendant_pre() but performs post-order | |
371 | * traversal instead. Synchronization rules are the same. @p_blkg is | |
372 | * included in the iteration and the last node to be visited. | |
373 | */ | |
374 | #define blkg_for_each_descendant_post(d_blkg, pos_css, p_blkg) \ | |
375 | css_for_each_descendant_post((pos_css), &(p_blkg)->blkcg->css) \ | |
79fcc5be | 376 | if (((d_blkg) = blkg_lookup(css_to_blkcg(pos_css), \ |
a06377c5 | 377 | (p_blkg)->q))) |
672fdcf0 | 378 | |
672fdcf0 ML |
379 | static inline void blkcg_bio_issue_init(struct bio *bio) |
380 | { | |
381 | bio_issue_init(&bio->bi_issue, bio_sectors(bio)); | |
382 | } | |
383 | ||
384 | static inline void blkcg_use_delay(struct blkcg_gq *blkg) | |
385 | { | |
386 | if (WARN_ON_ONCE(atomic_read(&blkg->use_delay) < 0)) | |
387 | return; | |
388 | if (atomic_add_return(1, &blkg->use_delay) == 1) | |
389 | atomic_inc(&blkg->blkcg->css.cgroup->congestion_count); | |
390 | } | |
391 | ||
392 | static inline int blkcg_unuse_delay(struct blkcg_gq *blkg) | |
393 | { | |
394 | int old = atomic_read(&blkg->use_delay); | |
395 | ||
396 | if (WARN_ON_ONCE(old < 0)) | |
397 | return 0; | |
398 | if (old == 0) | |
399 | return 0; | |
400 | ||
401 | /* | |
402 | * We do this song and dance because we can race with somebody else | |
403 | * adding or removing delay. If we just did an atomic_dec we'd end up | |
404 | * negative and we'd already be in trouble. We need to subtract 1 and | |
405 | * then check to see if we were the last delay so we can drop the | |
406 | * congestion count on the cgroup. | |
407 | */ | |
96388f57 UB |
408 | while (old && !atomic_try_cmpxchg(&blkg->use_delay, &old, old - 1)) |
409 | ; | |
672fdcf0 ML |
410 | |
411 | if (old == 0) | |
412 | return 0; | |
413 | if (old == 1) | |
414 | atomic_dec(&blkg->blkcg->css.cgroup->congestion_count); | |
415 | return 1; | |
416 | } | |
417 | ||
418 | /** | |
419 | * blkcg_set_delay - Enable allocator delay mechanism with the specified delay amount | |
420 | * @blkg: target blkg | |
421 | * @delay: delay duration in nsecs | |
422 | * | |
423 | * When enabled with this function, the delay is not decayed and must be | |
424 | * explicitly cleared with blkcg_clear_delay(). Must not be mixed with | |
425 | * blkcg_[un]use_delay() and blkcg_add_delay() usages. | |
426 | */ | |
427 | static inline void blkcg_set_delay(struct blkcg_gq *blkg, u64 delay) | |
428 | { | |
429 | int old = atomic_read(&blkg->use_delay); | |
430 | ||
431 | /* We only want 1 person setting the congestion count for this blkg. */ | |
96388f57 | 432 | if (!old && atomic_try_cmpxchg(&blkg->use_delay, &old, -1)) |
672fdcf0 ML |
433 | atomic_inc(&blkg->blkcg->css.cgroup->congestion_count); |
434 | ||
435 | atomic64_set(&blkg->delay_nsec, delay); | |
436 | } | |
437 | ||
438 | /** | |
439 | * blkcg_clear_delay - Disable allocator delay mechanism | |
440 | * @blkg: target blkg | |
441 | * | |
442 | * Disable use_delay mechanism. See blkcg_set_delay(). | |
443 | */ | |
444 | static inline void blkcg_clear_delay(struct blkcg_gq *blkg) | |
445 | { | |
446 | int old = atomic_read(&blkg->use_delay); | |
447 | ||
448 | /* We only want 1 person clearing the congestion count for this blkg. */ | |
96388f57 | 449 | if (old && atomic_try_cmpxchg(&blkg->use_delay, &old, 0)) |
672fdcf0 ML |
450 | atomic_dec(&blkg->blkcg->css.cgroup->congestion_count); |
451 | } | |
452 | ||
6b2b0459 TH |
453 | /** |
454 | * blk_cgroup_mergeable - Determine whether to allow or disallow merges | |
455 | * @rq: request to merge into | |
456 | * @bio: bio to merge | |
457 | * | |
458 | * @bio and @rq should belong to the same cgroup and their issue_as_root should | |
459 | * match. The latter is necessary as we don't want to throttle e.g. a metadata | |
460 | * update because it happens to be next to a regular IO. | |
461 | */ | |
462 | static inline bool blk_cgroup_mergeable(struct request *rq, struct bio *bio) | |
463 | { | |
464 | return rq->bio->bi_blkg == bio->bi_blkg && | |
465 | bio_issue_as_root_blkg(rq->bio) == bio_issue_as_root_blkg(bio); | |
466 | } | |
467 | ||
672fdcf0 ML |
468 | void blk_cgroup_bio_start(struct bio *bio); |
469 | void blkcg_add_delay(struct blkcg_gq *blkg, u64 now, u64 delta); | |
470 | #else /* CONFIG_BLK_CGROUP */ | |
471 | ||
472 | struct blkg_policy_data { | |
473 | }; | |
474 | ||
475 | struct blkcg_policy_data { | |
476 | }; | |
477 | ||
478 | struct blkcg_policy { | |
479 | }; | |
480 | ||
bbb1ebe7 CH |
481 | struct blkcg { |
482 | }; | |
483 | ||
672fdcf0 | 484 | static inline struct blkcg_gq *blkg_lookup(struct blkcg *blkcg, void *key) { return NULL; } |
9823538f CH |
485 | static inline int blkcg_init_disk(struct gendisk *disk) { return 0; } |
486 | static inline void blkcg_exit_disk(struct gendisk *disk) { } | |
672fdcf0 ML |
487 | static inline int blkcg_policy_register(struct blkcg_policy *pol) { return 0; } |
488 | static inline void blkcg_policy_unregister(struct blkcg_policy *pol) { } | |
40e4996e | 489 | static inline int blkcg_activate_policy(struct gendisk *disk, |
672fdcf0 | 490 | const struct blkcg_policy *pol) { return 0; } |
40e4996e | 491 | static inline void blkcg_deactivate_policy(struct gendisk *disk, |
672fdcf0 ML |
492 | const struct blkcg_policy *pol) { } |
493 | ||
672fdcf0 ML |
494 | static inline struct blkg_policy_data *blkg_to_pd(struct blkcg_gq *blkg, |
495 | struct blkcg_policy *pol) { return NULL; } | |
496 | static inline struct blkcg_gq *pd_to_blkg(struct blkg_policy_data *pd) { return NULL; } | |
497 | static inline char *blkg_path(struct blkcg_gq *blkg) { return NULL; } | |
498 | static inline void blkg_get(struct blkcg_gq *blkg) { } | |
499 | static inline void blkg_put(struct blkcg_gq *blkg) { } | |
672fdcf0 ML |
500 | static inline void blkcg_bio_issue_init(struct bio *bio) { } |
501 | static inline void blk_cgroup_bio_start(struct bio *bio) { } | |
6b2b0459 | 502 | static inline bool blk_cgroup_mergeable(struct request *rq, struct bio *bio) { return true; } |
672fdcf0 ML |
503 | |
504 | #define blk_queue_for_each_rl(rl, q) \ | |
505 | for ((rl) = &(q)->root_rl; (rl); (rl) = NULL) | |
506 | ||
672fdcf0 ML |
507 | #endif /* CONFIG_BLK_CGROUP */ |
508 | ||
509 | #endif /* _BLK_CGROUP_PRIVATE_H */ |