1 | // SPDX-License-Identifier: GPL-2.0 |
2 | #include <linux/kernel.h> |
3 | #include <linux/module.h> |
4 | #include <linux/backing-dev.h> |
5 | #include <linux/bio.h> |
6 | #include <linux/blkdev.h> |
7 | #include <linux/mm.h> |
8 | #include <linux/init.h> |
9 | #include <linux/slab.h> |
10 | #include <linux/workqueue.h> |
11 | #include <linux/smp.h> |
12 | |
13 | #include "blk.h" |
14 | #include "blk-mq.h" |
15 | |
16 | static void blk_mq_sysfs_release(struct kobject *kobj) |
17 | { |
18 | struct blk_mq_ctxs *ctxs = container_of(kobj, struct blk_mq_ctxs, kobj); |
19 | |
20 | free_percpu(pdata: ctxs->queue_ctx); |
21 | kfree(objp: ctxs); |
22 | } |
23 | |
24 | static void blk_mq_ctx_sysfs_release(struct kobject *kobj) |
25 | { |
26 | struct blk_mq_ctx *ctx = container_of(kobj, struct blk_mq_ctx, kobj); |
27 | |
28 | /* ctx->ctxs won't be released until all ctx are freed */ |
29 | kobject_put(kobj: &ctx->ctxs->kobj); |
30 | } |
31 | |
32 | static void blk_mq_hw_sysfs_release(struct kobject *kobj) |
33 | { |
34 | struct blk_mq_hw_ctx *hctx = container_of(kobj, struct blk_mq_hw_ctx, |
35 | kobj); |
36 | |
37 | blk_free_flush_queue(q: hctx->fq); |
38 | sbitmap_free(sb: &hctx->ctx_map); |
39 | free_cpumask_var(mask: hctx->cpumask); |
40 | kfree(objp: hctx->ctxs); |
41 | kfree(objp: hctx); |
42 | } |
43 | |
44 | struct blk_mq_hw_ctx_sysfs_entry { |
45 | struct attribute attr; |
46 | ssize_t (*show)(struct blk_mq_hw_ctx *, char *); |
47 | }; |
48 | |
49 | static ssize_t blk_mq_hw_sysfs_show(struct kobject *kobj, |
50 | struct attribute *attr, char *page) |
51 | { |
52 | struct blk_mq_hw_ctx_sysfs_entry *entry; |
53 | struct blk_mq_hw_ctx *hctx; |
54 | struct request_queue *q; |
55 | ssize_t res; |
56 | |
57 | entry = container_of(attr, struct blk_mq_hw_ctx_sysfs_entry, attr); |
58 | hctx = container_of(kobj, struct blk_mq_hw_ctx, kobj); |
59 | q = hctx->queue; |
60 | |
61 | if (!entry->show) |
62 | return -EIO; |
63 | |
64 | mutex_lock(&q->sysfs_lock); |
65 | res = entry->show(hctx, page); |
66 | mutex_unlock(lock: &q->sysfs_lock); |
67 | return res; |
68 | } |
69 | |
70 | static ssize_t blk_mq_hw_sysfs_nr_tags_show(struct blk_mq_hw_ctx *hctx, |
71 | char *page) |
72 | { |
73 | return sprintf(buf: page, fmt: "%u\n" , hctx->tags->nr_tags); |
74 | } |
75 | |
76 | static ssize_t blk_mq_hw_sysfs_nr_reserved_tags_show(struct blk_mq_hw_ctx *hctx, |
77 | char *page) |
78 | { |
79 | return sprintf(buf: page, fmt: "%u\n" , hctx->tags->nr_reserved_tags); |
80 | } |
81 | |
82 | static ssize_t blk_mq_hw_sysfs_cpus_show(struct blk_mq_hw_ctx *hctx, char *page) |
83 | { |
84 | const size_t size = PAGE_SIZE - 1; |
85 | unsigned int i, first = 1; |
86 | int ret = 0, pos = 0; |
87 | |
88 | for_each_cpu(i, hctx->cpumask) { |
89 | if (first) |
90 | ret = snprintf(buf: pos + page, size: size - pos, fmt: "%u" , i); |
91 | else |
92 | ret = snprintf(buf: pos + page, size: size - pos, fmt: ", %u" , i); |
93 | |
94 | if (ret >= size - pos) |
95 | break; |
96 | |
97 | first = 0; |
98 | pos += ret; |
99 | } |
100 | |
101 | ret = snprintf(buf: pos + page, size: size + 1 - pos, fmt: "\n" ); |
102 | return pos + ret; |
103 | } |
104 | |
105 | static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_nr_tags = { |
106 | .attr = {.name = "nr_tags" , .mode = 0444 }, |
107 | .show = blk_mq_hw_sysfs_nr_tags_show, |
108 | }; |
109 | static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_nr_reserved_tags = { |
110 | .attr = {.name = "nr_reserved_tags" , .mode = 0444 }, |
111 | .show = blk_mq_hw_sysfs_nr_reserved_tags_show, |
112 | }; |
113 | static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_cpus = { |
114 | .attr = {.name = "cpu_list" , .mode = 0444 }, |
115 | .show = blk_mq_hw_sysfs_cpus_show, |
116 | }; |
117 | |
118 | static struct attribute *default_hw_ctx_attrs[] = { |
119 | &blk_mq_hw_sysfs_nr_tags.attr, |
120 | &blk_mq_hw_sysfs_nr_reserved_tags.attr, |
121 | &blk_mq_hw_sysfs_cpus.attr, |
122 | NULL, |
123 | }; |
124 | ATTRIBUTE_GROUPS(default_hw_ctx); |
125 | |
126 | static const struct sysfs_ops blk_mq_hw_sysfs_ops = { |
127 | .show = blk_mq_hw_sysfs_show, |
128 | }; |
129 | |
130 | static const struct kobj_type blk_mq_ktype = { |
131 | .release = blk_mq_sysfs_release, |
132 | }; |
133 | |
134 | static const struct kobj_type blk_mq_ctx_ktype = { |
135 | .release = blk_mq_ctx_sysfs_release, |
136 | }; |
137 | |
138 | static const struct kobj_type blk_mq_hw_ktype = { |
139 | .sysfs_ops = &blk_mq_hw_sysfs_ops, |
140 | .default_groups = default_hw_ctx_groups, |
141 | .release = blk_mq_hw_sysfs_release, |
142 | }; |
143 | |
144 | static void blk_mq_unregister_hctx(struct blk_mq_hw_ctx *hctx) |
145 | { |
146 | struct blk_mq_ctx *ctx; |
147 | int i; |
148 | |
149 | if (!hctx->nr_ctx) |
150 | return; |
151 | |
152 | hctx_for_each_ctx(hctx, ctx, i) |
153 | kobject_del(kobj: &ctx->kobj); |
154 | |
155 | kobject_del(kobj: &hctx->kobj); |
156 | } |
157 | |
158 | static int blk_mq_register_hctx(struct blk_mq_hw_ctx *hctx) |
159 | { |
160 | struct request_queue *q = hctx->queue; |
161 | struct blk_mq_ctx *ctx; |
162 | int i, j, ret; |
163 | |
164 | if (!hctx->nr_ctx) |
165 | return 0; |
166 | |
167 | ret = kobject_add(kobj: &hctx->kobj, parent: q->mq_kobj, fmt: "%u" , hctx->queue_num); |
168 | if (ret) |
169 | return ret; |
170 | |
171 | hctx_for_each_ctx(hctx, ctx, i) { |
172 | ret = kobject_add(kobj: &ctx->kobj, parent: &hctx->kobj, fmt: "cpu%u" , ctx->cpu); |
173 | if (ret) |
174 | goto out; |
175 | } |
176 | |
177 | return 0; |
178 | out: |
179 | hctx_for_each_ctx(hctx, ctx, j) { |
180 | if (j < i) |
181 | kobject_del(kobj: &ctx->kobj); |
182 | } |
183 | kobject_del(kobj: &hctx->kobj); |
184 | return ret; |
185 | } |
186 | |
187 | void blk_mq_hctx_kobj_init(struct blk_mq_hw_ctx *hctx) |
188 | { |
189 | kobject_init(kobj: &hctx->kobj, ktype: &blk_mq_hw_ktype); |
190 | } |
191 | |
192 | void blk_mq_sysfs_deinit(struct request_queue *q) |
193 | { |
194 | struct blk_mq_ctx *ctx; |
195 | int cpu; |
196 | |
197 | for_each_possible_cpu(cpu) { |
198 | ctx = per_cpu_ptr(q->queue_ctx, cpu); |
199 | kobject_put(kobj: &ctx->kobj); |
200 | } |
201 | kobject_put(kobj: q->mq_kobj); |
202 | } |
203 | |
204 | void blk_mq_sysfs_init(struct request_queue *q) |
205 | { |
206 | struct blk_mq_ctx *ctx; |
207 | int cpu; |
208 | |
209 | kobject_init(kobj: q->mq_kobj, ktype: &blk_mq_ktype); |
210 | |
211 | for_each_possible_cpu(cpu) { |
212 | ctx = per_cpu_ptr(q->queue_ctx, cpu); |
213 | |
214 | kobject_get(kobj: q->mq_kobj); |
215 | kobject_init(kobj: &ctx->kobj, ktype: &blk_mq_ctx_ktype); |
216 | } |
217 | } |
218 | |
219 | int blk_mq_sysfs_register(struct gendisk *disk) |
220 | { |
221 | struct request_queue *q = disk->queue; |
222 | struct blk_mq_hw_ctx *hctx; |
223 | unsigned long i, j; |
224 | int ret; |
225 | |
226 | lockdep_assert_held(&q->sysfs_dir_lock); |
227 | |
228 | ret = kobject_add(kobj: q->mq_kobj, parent: &disk_to_dev(disk)->kobj, fmt: "mq" ); |
229 | if (ret < 0) |
230 | goto out; |
231 | |
232 | kobject_uevent(kobj: q->mq_kobj, action: KOBJ_ADD); |
233 | |
234 | queue_for_each_hw_ctx(q, hctx, i) { |
235 | ret = blk_mq_register_hctx(hctx); |
236 | if (ret) |
237 | goto unreg; |
238 | } |
239 | |
240 | q->mq_sysfs_init_done = true; |
241 | |
242 | out: |
243 | return ret; |
244 | |
245 | unreg: |
246 | queue_for_each_hw_ctx(q, hctx, j) { |
247 | if (j < i) |
248 | blk_mq_unregister_hctx(hctx); |
249 | } |
250 | |
251 | kobject_uevent(kobj: q->mq_kobj, action: KOBJ_REMOVE); |
252 | kobject_del(kobj: q->mq_kobj); |
253 | return ret; |
254 | } |
255 | |
256 | void blk_mq_sysfs_unregister(struct gendisk *disk) |
257 | { |
258 | struct request_queue *q = disk->queue; |
259 | struct blk_mq_hw_ctx *hctx; |
260 | unsigned long i; |
261 | |
262 | lockdep_assert_held(&q->sysfs_dir_lock); |
263 | |
264 | queue_for_each_hw_ctx(q, hctx, i) |
265 | blk_mq_unregister_hctx(hctx); |
266 | |
267 | kobject_uevent(kobj: q->mq_kobj, action: KOBJ_REMOVE); |
268 | kobject_del(kobj: q->mq_kobj); |
269 | |
270 | q->mq_sysfs_init_done = false; |
271 | } |
272 | |
273 | void blk_mq_sysfs_unregister_hctxs(struct request_queue *q) |
274 | { |
275 | struct blk_mq_hw_ctx *hctx; |
276 | unsigned long i; |
277 | |
278 | mutex_lock(&q->sysfs_dir_lock); |
279 | if (!q->mq_sysfs_init_done) |
280 | goto unlock; |
281 | |
282 | queue_for_each_hw_ctx(q, hctx, i) |
283 | blk_mq_unregister_hctx(hctx); |
284 | |
285 | unlock: |
286 | mutex_unlock(lock: &q->sysfs_dir_lock); |
287 | } |
288 | |
289 | int blk_mq_sysfs_register_hctxs(struct request_queue *q) |
290 | { |
291 | struct blk_mq_hw_ctx *hctx; |
292 | unsigned long i; |
293 | int ret = 0; |
294 | |
295 | mutex_lock(&q->sysfs_dir_lock); |
296 | if (!q->mq_sysfs_init_done) |
297 | goto unlock; |
298 | |
299 | queue_for_each_hw_ctx(q, hctx, i) { |
300 | ret = blk_mq_register_hctx(hctx); |
301 | if (ret) |
302 | break; |
303 | } |
304 | |
305 | unlock: |
306 | mutex_unlock(lock: &q->sysfs_dir_lock); |
307 | |
308 | return ret; |
309 | } |
310 | |