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71f28f31 ML |
1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* | |
3 | * Userspace block device - block device which IO is handled from userspace | |
4 | * | |
5 | * Take full use of io_uring passthrough command for communicating with | |
6 | * ublk userspace daemon(ublksrvd) for handling basic IO request. | |
7 | * | |
8 | * Copyright 2022 Ming Lei <ming.lei@redhat.com> | |
9 | * | |
10 | * (part of code stolen from loop.c) | |
11 | */ | |
12 | #include <linux/module.h> | |
13 | #include <linux/moduleparam.h> | |
14 | #include <linux/sched.h> | |
15 | #include <linux/fs.h> | |
16 | #include <linux/pagemap.h> | |
17 | #include <linux/file.h> | |
18 | #include <linux/stat.h> | |
19 | #include <linux/errno.h> | |
20 | #include <linux/major.h> | |
21 | #include <linux/wait.h> | |
22 | #include <linux/blkdev.h> | |
23 | #include <linux/init.h> | |
24 | #include <linux/swap.h> | |
25 | #include <linux/slab.h> | |
26 | #include <linux/compat.h> | |
27 | #include <linux/mutex.h> | |
28 | #include <linux/writeback.h> | |
29 | #include <linux/completion.h> | |
30 | #include <linux/highmem.h> | |
31 | #include <linux/sysfs.h> | |
32 | #include <linux/miscdevice.h> | |
33 | #include <linux/falloc.h> | |
34 | #include <linux/uio.h> | |
35 | #include <linux/ioprio.h> | |
36 | #include <linux/sched/mm.h> | |
37 | #include <linux/uaccess.h> | |
38 | #include <linux/cdev.h> | |
39 | #include <linux/io_uring.h> | |
40 | #include <linux/blk-mq.h> | |
41 | #include <linux/delay.h> | |
42 | #include <linux/mm.h> | |
43 | #include <asm/page.h> | |
0edb3696 | 44 | #include <linux/task_work.h> |
71f28f31 ML |
45 | #include <uapi/linux/ublk_cmd.h> |
46 | ||
47 | #define UBLK_MINORS (1U << MINORBITS) | |
48 | ||
6d8c5afc ML |
49 | /* All UBLK_F_* have to be included into UBLK_F_ALL */ |
50 | #define UBLK_F_ALL (UBLK_F_SUPPORT_ZERO_COPY | UBLK_F_URING_CMD_COMP_IN_TASK) | |
51 | ||
0aa73170 ML |
52 | /* All UBLK_PARAM_TYPE_* should be included here */ |
53 | #define UBLK_PARAM_TYPE_ALL (UBLK_PARAM_TYPE_BASIC | UBLK_PARAM_TYPE_DISCARD) | |
54 | ||
0edb3696 ML |
55 | struct ublk_rq_data { |
56 | struct callback_head work; | |
57 | }; | |
58 | ||
71f28f31 ML |
59 | struct ublk_uring_cmd_pdu { |
60 | struct request *req; | |
61 | }; | |
62 | ||
63 | /* | |
64 | * io command is active: sqe cmd is received, and its cqe isn't done | |
65 | * | |
66 | * If the flag is set, the io command is owned by ublk driver, and waited | |
67 | * for incoming blk-mq request from the ublk block device. | |
68 | * | |
69 | * If the flag is cleared, the io command will be completed, and owned by | |
70 | * ublk server. | |
71 | */ | |
72 | #define UBLK_IO_FLAG_ACTIVE 0x01 | |
73 | ||
74 | /* | |
75 | * IO command is completed via cqe, and it is being handled by ublksrv, and | |
76 | * not committed yet | |
77 | * | |
78 | * Basically exclusively with UBLK_IO_FLAG_ACTIVE, so can be served for | |
79 | * cross verification | |
80 | */ | |
81 | #define UBLK_IO_FLAG_OWNED_BY_SRV 0x02 | |
82 | ||
83 | /* | |
84 | * IO command is aborted, so this flag is set in case of | |
85 | * !UBLK_IO_FLAG_ACTIVE. | |
86 | * | |
87 | * After this flag is observed, any pending or new incoming request | |
88 | * associated with this io command will be failed immediately | |
89 | */ | |
90 | #define UBLK_IO_FLAG_ABORTED 0x04 | |
91 | ||
92 | struct ublk_io { | |
93 | /* userspace buffer address from io cmd */ | |
94 | __u64 addr; | |
95 | unsigned int flags; | |
96 | int res; | |
97 | ||
98 | struct io_uring_cmd *cmd; | |
99 | }; | |
100 | ||
101 | struct ublk_queue { | |
102 | int q_id; | |
103 | int q_depth; | |
104 | ||
0edb3696 | 105 | unsigned long flags; |
71f28f31 ML |
106 | struct task_struct *ubq_daemon; |
107 | char *io_cmd_buf; | |
108 | ||
109 | unsigned long io_addr; /* mapped vm address */ | |
110 | unsigned int max_io_sz; | |
111 | bool abort_work_pending; | |
112 | unsigned short nr_io_ready; /* how many ios setup */ | |
113 | struct ublk_device *dev; | |
114 | struct ublk_io ios[0]; | |
115 | }; | |
116 | ||
117 | #define UBLK_DAEMON_MONITOR_PERIOD (5 * HZ) | |
118 | ||
119 | struct ublk_device { | |
120 | struct gendisk *ub_disk; | |
71f28f31 ML |
121 | |
122 | char *__queues; | |
123 | ||
124 | unsigned short queue_size; | |
71f28f31 ML |
125 | struct ublksrv_ctrl_dev_info dev_info; |
126 | ||
127 | struct blk_mq_tag_set tag_set; | |
128 | ||
129 | struct cdev cdev; | |
130 | struct device cdev_dev; | |
131 | ||
8d9fdb60 DC |
132 | #define UB_STATE_OPEN 0 |
133 | #define UB_STATE_USED 1 | |
fa362045 | 134 | unsigned long state; |
71f28f31 ML |
135 | int ub_number; |
136 | ||
137 | struct mutex mutex; | |
138 | ||
e94eb459 | 139 | spinlock_t mm_lock; |
71f28f31 ML |
140 | struct mm_struct *mm; |
141 | ||
0aa73170 ML |
142 | struct ublk_params params; |
143 | ||
71f28f31 ML |
144 | struct completion completion; |
145 | unsigned int nr_queues_ready; | |
146 | atomic_t nr_aborted_queues; | |
147 | ||
148 | /* | |
149 | * Our ubq->daemon may be killed without any notification, so | |
150 | * monitor each queue's daemon periodically | |
151 | */ | |
152 | struct delayed_work monitor_work; | |
153 | struct work_struct stop_work; | |
154 | }; | |
155 | ||
0aa73170 ML |
156 | /* header of ublk_params */ |
157 | struct ublk_params_header { | |
158 | __u32 len; | |
159 | __u32 types; | |
160 | }; | |
161 | ||
71f28f31 ML |
162 | static dev_t ublk_chr_devt; |
163 | static struct class *ublk_chr_class; | |
164 | ||
165 | static DEFINE_IDR(ublk_index_idr); | |
166 | static DEFINE_SPINLOCK(ublk_idr_lock); | |
167 | static wait_queue_head_t ublk_idr_wq; /* wait until one idr is freed */ | |
168 | ||
169 | static DEFINE_MUTEX(ublk_ctl_mutex); | |
170 | ||
171 | static struct miscdevice ublk_misc; | |
172 | ||
0aa73170 ML |
173 | static void ublk_dev_param_basic_apply(struct ublk_device *ub) |
174 | { | |
175 | struct request_queue *q = ub->ub_disk->queue; | |
176 | const struct ublk_param_basic *p = &ub->params.basic; | |
177 | ||
178 | blk_queue_logical_block_size(q, 1 << p->logical_bs_shift); | |
179 | blk_queue_physical_block_size(q, 1 << p->physical_bs_shift); | |
180 | blk_queue_io_min(q, 1 << p->io_min_shift); | |
181 | blk_queue_io_opt(q, 1 << p->io_opt_shift); | |
182 | ||
183 | blk_queue_write_cache(q, p->attrs & UBLK_ATTR_VOLATILE_CACHE, | |
184 | p->attrs & UBLK_ATTR_FUA); | |
185 | if (p->attrs & UBLK_ATTR_ROTATIONAL) | |
186 | blk_queue_flag_clear(QUEUE_FLAG_NONROT, q); | |
187 | else | |
188 | blk_queue_flag_set(QUEUE_FLAG_NONROT, q); | |
189 | ||
190 | blk_queue_max_hw_sectors(q, p->max_sectors); | |
191 | blk_queue_chunk_sectors(q, p->chunk_sectors); | |
192 | blk_queue_virt_boundary(q, p->virt_boundary_mask); | |
193 | ||
194 | if (p->attrs & UBLK_ATTR_READ_ONLY) | |
195 | set_disk_ro(ub->ub_disk, true); | |
196 | ||
197 | set_capacity(ub->ub_disk, p->dev_sectors); | |
198 | } | |
199 | ||
200 | static void ublk_dev_param_discard_apply(struct ublk_device *ub) | |
201 | { | |
202 | struct request_queue *q = ub->ub_disk->queue; | |
203 | const struct ublk_param_discard *p = &ub->params.discard; | |
204 | ||
205 | q->limits.discard_alignment = p->discard_alignment; | |
206 | q->limits.discard_granularity = p->discard_granularity; | |
207 | blk_queue_max_discard_sectors(q, p->max_discard_sectors); | |
208 | blk_queue_max_write_zeroes_sectors(q, | |
209 | p->max_write_zeroes_sectors); | |
210 | blk_queue_max_discard_segments(q, p->max_discard_segments); | |
211 | } | |
212 | ||
213 | static int ublk_validate_params(const struct ublk_device *ub) | |
214 | { | |
215 | /* basic param is the only one which must be set */ | |
216 | if (ub->params.types & UBLK_PARAM_TYPE_BASIC) { | |
217 | const struct ublk_param_basic *p = &ub->params.basic; | |
218 | ||
219 | if (p->logical_bs_shift > PAGE_SHIFT) | |
220 | return -EINVAL; | |
221 | ||
222 | if (p->logical_bs_shift > p->physical_bs_shift) | |
223 | return -EINVAL; | |
224 | ||
4bf9cbf3 | 225 | if (p->max_sectors > (ub->dev_info.max_io_buf_bytes >> 9)) |
0aa73170 ML |
226 | return -EINVAL; |
227 | } else | |
228 | return -EINVAL; | |
229 | ||
230 | if (ub->params.types & UBLK_PARAM_TYPE_DISCARD) { | |
231 | const struct ublk_param_discard *p = &ub->params.discard; | |
232 | ||
233 | /* So far, only support single segment discard */ | |
234 | if (p->max_discard_sectors && p->max_discard_segments != 1) | |
235 | return -EINVAL; | |
236 | ||
237 | if (!p->discard_granularity) | |
238 | return -EINVAL; | |
239 | } | |
240 | ||
241 | return 0; | |
242 | } | |
243 | ||
244 | static int ublk_apply_params(struct ublk_device *ub) | |
245 | { | |
246 | if (!(ub->params.types & UBLK_PARAM_TYPE_BASIC)) | |
247 | return -EINVAL; | |
248 | ||
249 | ublk_dev_param_basic_apply(ub); | |
250 | ||
251 | if (ub->params.types & UBLK_PARAM_TYPE_DISCARD) | |
252 | ublk_dev_param_discard_apply(ub); | |
253 | ||
254 | return 0; | |
255 | } | |
256 | ||
0edb3696 ML |
257 | static inline bool ublk_can_use_task_work(const struct ublk_queue *ubq) |
258 | { | |
259 | if (IS_BUILTIN(CONFIG_BLK_DEV_UBLK) && | |
260 | !(ubq->flags & UBLK_F_URING_CMD_COMP_IN_TASK)) | |
261 | return true; | |
262 | return false; | |
263 | } | |
264 | ||
71f28f31 ML |
265 | static struct ublk_device *ublk_get_device(struct ublk_device *ub) |
266 | { | |
267 | if (kobject_get_unless_zero(&ub->cdev_dev.kobj)) | |
268 | return ub; | |
269 | return NULL; | |
270 | } | |
271 | ||
272 | static void ublk_put_device(struct ublk_device *ub) | |
273 | { | |
274 | put_device(&ub->cdev_dev); | |
275 | } | |
276 | ||
277 | static inline struct ublk_queue *ublk_get_queue(struct ublk_device *dev, | |
278 | int qid) | |
279 | { | |
280 | return (struct ublk_queue *)&(dev->__queues[qid * dev->queue_size]); | |
281 | } | |
282 | ||
283 | static inline bool ublk_rq_has_data(const struct request *rq) | |
284 | { | |
285 | return rq->bio && bio_has_data(rq->bio); | |
286 | } | |
287 | ||
288 | static inline struct ublksrv_io_desc *ublk_get_iod(struct ublk_queue *ubq, | |
289 | int tag) | |
290 | { | |
291 | return (struct ublksrv_io_desc *) | |
292 | &(ubq->io_cmd_buf[tag * sizeof(struct ublksrv_io_desc)]); | |
293 | } | |
294 | ||
295 | static inline char *ublk_queue_cmd_buf(struct ublk_device *ub, int q_id) | |
296 | { | |
297 | return ublk_get_queue(ub, q_id)->io_cmd_buf; | |
298 | } | |
299 | ||
300 | static inline int ublk_queue_cmd_buf_size(struct ublk_device *ub, int q_id) | |
301 | { | |
302 | struct ublk_queue *ubq = ublk_get_queue(ub, q_id); | |
303 | ||
304 | return round_up(ubq->q_depth * sizeof(struct ublksrv_io_desc), | |
305 | PAGE_SIZE); | |
306 | } | |
307 | ||
6d9e6dfd CH |
308 | static void ublk_free_disk(struct gendisk *disk) |
309 | { | |
310 | struct ublk_device *ub = disk->private_data; | |
311 | ||
312 | clear_bit(UB_STATE_USED, &ub->state); | |
313 | put_device(&ub->cdev_dev); | |
314 | } | |
315 | ||
71f28f31 ML |
316 | static const struct block_device_operations ub_fops = { |
317 | .owner = THIS_MODULE, | |
6d9e6dfd | 318 | .free_disk = ublk_free_disk, |
71f28f31 ML |
319 | }; |
320 | ||
321 | #define UBLK_MAX_PIN_PAGES 32 | |
322 | ||
323 | struct ublk_map_data { | |
324 | const struct ublk_queue *ubq; | |
325 | const struct request *rq; | |
326 | const struct ublk_io *io; | |
327 | unsigned max_bytes; | |
328 | }; | |
329 | ||
330 | struct ublk_io_iter { | |
331 | struct page *pages[UBLK_MAX_PIN_PAGES]; | |
332 | unsigned pg_off; /* offset in the 1st page in pages */ | |
333 | int nr_pages; /* how many page pointers in pages */ | |
334 | struct bio *bio; | |
335 | struct bvec_iter iter; | |
336 | }; | |
337 | ||
338 | static inline unsigned ublk_copy_io_pages(struct ublk_io_iter *data, | |
339 | unsigned max_bytes, bool to_vm) | |
340 | { | |
341 | const unsigned total = min_t(unsigned, max_bytes, | |
342 | PAGE_SIZE - data->pg_off + | |
343 | ((data->nr_pages - 1) << PAGE_SHIFT)); | |
344 | unsigned done = 0; | |
345 | unsigned pg_idx = 0; | |
346 | ||
347 | while (done < total) { | |
348 | struct bio_vec bv = bio_iter_iovec(data->bio, data->iter); | |
349 | const unsigned int bytes = min3(bv.bv_len, total - done, | |
350 | (unsigned)(PAGE_SIZE - data->pg_off)); | |
351 | void *bv_buf = bvec_kmap_local(&bv); | |
352 | void *pg_buf = kmap_local_page(data->pages[pg_idx]); | |
353 | ||
354 | if (to_vm) | |
355 | memcpy(pg_buf + data->pg_off, bv_buf, bytes); | |
356 | else | |
357 | memcpy(bv_buf, pg_buf + data->pg_off, bytes); | |
358 | ||
359 | kunmap_local(pg_buf); | |
360 | kunmap_local(bv_buf); | |
361 | ||
362 | /* advance page array */ | |
363 | data->pg_off += bytes; | |
364 | if (data->pg_off == PAGE_SIZE) { | |
365 | pg_idx += 1; | |
366 | data->pg_off = 0; | |
367 | } | |
368 | ||
369 | done += bytes; | |
370 | ||
371 | /* advance bio */ | |
372 | bio_advance_iter_single(data->bio, &data->iter, bytes); | |
373 | if (!data->iter.bi_size) { | |
374 | data->bio = data->bio->bi_next; | |
375 | if (data->bio == NULL) | |
376 | break; | |
377 | data->iter = data->bio->bi_iter; | |
378 | } | |
379 | } | |
380 | ||
381 | return done; | |
382 | } | |
383 | ||
384 | static inline int ublk_copy_user_pages(struct ublk_map_data *data, | |
385 | bool to_vm) | |
386 | { | |
387 | const unsigned int gup_flags = to_vm ? FOLL_WRITE : 0; | |
388 | const unsigned long start_vm = data->io->addr; | |
389 | unsigned int done = 0; | |
390 | struct ublk_io_iter iter = { | |
391 | .pg_off = start_vm & (PAGE_SIZE - 1), | |
392 | .bio = data->rq->bio, | |
393 | .iter = data->rq->bio->bi_iter, | |
394 | }; | |
395 | const unsigned int nr_pages = round_up(data->max_bytes + | |
396 | (start_vm & (PAGE_SIZE - 1)), PAGE_SIZE) >> PAGE_SHIFT; | |
397 | ||
398 | while (done < nr_pages) { | |
399 | const unsigned to_pin = min_t(unsigned, UBLK_MAX_PIN_PAGES, | |
400 | nr_pages - done); | |
401 | unsigned i, len; | |
402 | ||
403 | iter.nr_pages = get_user_pages_fast(start_vm + | |
404 | (done << PAGE_SHIFT), to_pin, gup_flags, | |
405 | iter.pages); | |
406 | if (iter.nr_pages <= 0) | |
407 | return done == 0 ? iter.nr_pages : done; | |
408 | len = ublk_copy_io_pages(&iter, data->max_bytes, to_vm); | |
409 | for (i = 0; i < iter.nr_pages; i++) { | |
410 | if (to_vm) | |
411 | set_page_dirty(iter.pages[i]); | |
412 | put_page(iter.pages[i]); | |
413 | } | |
414 | data->max_bytes -= len; | |
415 | done += iter.nr_pages; | |
416 | } | |
417 | ||
418 | return done; | |
419 | } | |
420 | ||
421 | static int ublk_map_io(const struct ublk_queue *ubq, const struct request *req, | |
422 | struct ublk_io *io) | |
423 | { | |
424 | const unsigned int rq_bytes = blk_rq_bytes(req); | |
425 | /* | |
426 | * no zero copy, we delay copy WRITE request data into ublksrv | |
427 | * context and the big benefit is that pinning pages in current | |
428 | * context is pretty fast, see ublk_pin_user_pages | |
429 | */ | |
430 | if (req_op(req) != REQ_OP_WRITE && req_op(req) != REQ_OP_FLUSH) | |
431 | return rq_bytes; | |
432 | ||
433 | if (ublk_rq_has_data(req)) { | |
434 | struct ublk_map_data data = { | |
435 | .ubq = ubq, | |
436 | .rq = req, | |
437 | .io = io, | |
438 | .max_bytes = rq_bytes, | |
439 | }; | |
440 | ||
441 | ublk_copy_user_pages(&data, true); | |
442 | ||
443 | return rq_bytes - data.max_bytes; | |
444 | } | |
445 | return rq_bytes; | |
446 | } | |
447 | ||
448 | static int ublk_unmap_io(const struct ublk_queue *ubq, | |
449 | const struct request *req, | |
450 | struct ublk_io *io) | |
451 | { | |
452 | const unsigned int rq_bytes = blk_rq_bytes(req); | |
453 | ||
454 | if (req_op(req) == REQ_OP_READ && ublk_rq_has_data(req)) { | |
455 | struct ublk_map_data data = { | |
456 | .ubq = ubq, | |
457 | .rq = req, | |
458 | .io = io, | |
459 | .max_bytes = io->res, | |
460 | }; | |
461 | ||
462 | WARN_ON_ONCE(io->res > rq_bytes); | |
463 | ||
464 | ublk_copy_user_pages(&data, false); | |
465 | ||
466 | return io->res - data.max_bytes; | |
467 | } | |
468 | return rq_bytes; | |
469 | } | |
470 | ||
471 | static inline unsigned int ublk_req_build_flags(struct request *req) | |
472 | { | |
473 | unsigned flags = 0; | |
474 | ||
475 | if (req->cmd_flags & REQ_FAILFAST_DEV) | |
476 | flags |= UBLK_IO_F_FAILFAST_DEV; | |
477 | ||
478 | if (req->cmd_flags & REQ_FAILFAST_TRANSPORT) | |
479 | flags |= UBLK_IO_F_FAILFAST_TRANSPORT; | |
480 | ||
481 | if (req->cmd_flags & REQ_FAILFAST_DRIVER) | |
482 | flags |= UBLK_IO_F_FAILFAST_DRIVER; | |
483 | ||
484 | if (req->cmd_flags & REQ_META) | |
485 | flags |= UBLK_IO_F_META; | |
486 | ||
71f28f31 ML |
487 | if (req->cmd_flags & REQ_FUA) |
488 | flags |= UBLK_IO_F_FUA; | |
489 | ||
71f28f31 ML |
490 | if (req->cmd_flags & REQ_NOUNMAP) |
491 | flags |= UBLK_IO_F_NOUNMAP; | |
492 | ||
493 | if (req->cmd_flags & REQ_SWAP) | |
494 | flags |= UBLK_IO_F_SWAP; | |
495 | ||
496 | return flags; | |
497 | } | |
498 | ||
f2450f8a | 499 | static blk_status_t ublk_setup_iod(struct ublk_queue *ubq, struct request *req) |
71f28f31 ML |
500 | { |
501 | struct ublksrv_io_desc *iod = ublk_get_iod(ubq, req->tag); | |
502 | struct ublk_io *io = &ubq->ios[req->tag]; | |
503 | u32 ublk_op; | |
504 | ||
505 | switch (req_op(req)) { | |
506 | case REQ_OP_READ: | |
507 | ublk_op = UBLK_IO_OP_READ; | |
508 | break; | |
509 | case REQ_OP_WRITE: | |
510 | ublk_op = UBLK_IO_OP_WRITE; | |
511 | break; | |
512 | case REQ_OP_FLUSH: | |
513 | ublk_op = UBLK_IO_OP_FLUSH; | |
514 | break; | |
515 | case REQ_OP_DISCARD: | |
516 | ublk_op = UBLK_IO_OP_DISCARD; | |
517 | break; | |
518 | case REQ_OP_WRITE_ZEROES: | |
519 | ublk_op = UBLK_IO_OP_WRITE_ZEROES; | |
520 | break; | |
521 | default: | |
522 | return BLK_STS_IOERR; | |
523 | } | |
524 | ||
525 | /* need to translate since kernel may change */ | |
526 | iod->op_flags = ublk_op | ublk_req_build_flags(req); | |
527 | iod->nr_sectors = blk_rq_sectors(req); | |
528 | iod->start_sector = blk_rq_pos(req); | |
529 | iod->addr = io->addr; | |
530 | ||
531 | return BLK_STS_OK; | |
532 | } | |
533 | ||
534 | static inline struct ublk_uring_cmd_pdu *ublk_get_uring_cmd_pdu( | |
535 | struct io_uring_cmd *ioucmd) | |
536 | { | |
537 | return (struct ublk_uring_cmd_pdu *)&ioucmd->pdu; | |
538 | } | |
539 | ||
540 | static bool ubq_daemon_is_dying(struct ublk_queue *ubq) | |
541 | { | |
542 | return ubq->ubq_daemon->flags & PF_EXITING; | |
543 | } | |
544 | ||
545 | /* todo: handle partial completion */ | |
546 | static void ublk_complete_rq(struct request *req) | |
547 | { | |
548 | struct ublk_queue *ubq = req->mq_hctx->driver_data; | |
549 | struct ublk_io *io = &ubq->ios[req->tag]; | |
550 | unsigned int unmapped_bytes; | |
551 | ||
552 | /* failed read IO if nothing is read */ | |
553 | if (!io->res && req_op(req) == REQ_OP_READ) | |
554 | io->res = -EIO; | |
555 | ||
556 | if (io->res < 0) { | |
557 | blk_mq_end_request(req, errno_to_blk_status(io->res)); | |
558 | return; | |
559 | } | |
560 | ||
561 | /* | |
562 | * FLUSH or DISCARD usually won't return bytes returned, so end them | |
563 | * directly. | |
564 | * | |
565 | * Both the two needn't unmap. | |
566 | */ | |
567 | if (req_op(req) != REQ_OP_READ && req_op(req) != REQ_OP_WRITE) { | |
568 | blk_mq_end_request(req, BLK_STS_OK); | |
569 | return; | |
570 | } | |
571 | ||
572 | /* for READ request, writing data in iod->addr to rq buffers */ | |
573 | unmapped_bytes = ublk_unmap_io(ubq, req, io); | |
574 | ||
575 | /* | |
576 | * Extremely impossible since we got data filled in just before | |
577 | * | |
578 | * Re-read simply for this unlikely case. | |
579 | */ | |
580 | if (unlikely(unmapped_bytes < io->res)) | |
581 | io->res = unmapped_bytes; | |
582 | ||
583 | if (blk_update_request(req, BLK_STS_OK, io->res)) | |
584 | blk_mq_requeue_request(req, true); | |
585 | else | |
586 | __blk_mq_end_request(req, BLK_STS_OK); | |
587 | } | |
588 | ||
589 | /* | |
590 | * __ublk_fail_req() may be called from abort context or ->ubq_daemon | |
591 | * context during exiting, so lock is required. | |
592 | * | |
593 | * Also aborting may not be started yet, keep in mind that one failed | |
594 | * request may be issued by block layer again. | |
595 | */ | |
596 | static void __ublk_fail_req(struct ublk_io *io, struct request *req) | |
597 | { | |
598 | WARN_ON_ONCE(io->flags & UBLK_IO_FLAG_ACTIVE); | |
599 | ||
600 | if (!(io->flags & UBLK_IO_FLAG_ABORTED)) { | |
601 | io->flags |= UBLK_IO_FLAG_ABORTED; | |
602 | blk_mq_end_request(req, BLK_STS_IOERR); | |
603 | } | |
604 | } | |
605 | ||
606 | #define UBLK_REQUEUE_DELAY_MS 3 | |
607 | ||
0edb3696 | 608 | static inline void __ublk_rq_task_work(struct request *req) |
71f28f31 | 609 | { |
71f28f31 | 610 | struct ublk_queue *ubq = req->mq_hctx->driver_data; |
0edb3696 | 611 | struct ublk_device *ub = ubq->dev; |
71f28f31 ML |
612 | int tag = req->tag; |
613 | struct ublk_io *io = &ubq->ios[tag]; | |
614 | bool task_exiting = current != ubq->ubq_daemon || | |
615 | (current->flags & PF_EXITING); | |
616 | unsigned int mapped_bytes; | |
617 | ||
618 | pr_devel("%s: complete: op %d, qid %d tag %d io_flags %x addr %llx\n", | |
619 | __func__, io->cmd->cmd_op, ubq->q_id, req->tag, io->flags, | |
620 | ublk_get_iod(ubq, req->tag)->addr); | |
621 | ||
622 | if (unlikely(task_exiting)) { | |
623 | blk_mq_end_request(req, BLK_STS_IOERR); | |
624 | mod_delayed_work(system_wq, &ub->monitor_work, 0); | |
625 | return; | |
626 | } | |
627 | ||
628 | mapped_bytes = ublk_map_io(ubq, req, io); | |
629 | ||
630 | /* partially mapped, update io descriptor */ | |
631 | if (unlikely(mapped_bytes != blk_rq_bytes(req))) { | |
632 | /* | |
633 | * Nothing mapped, retry until we succeed. | |
634 | * | |
635 | * We may never succeed in mapping any bytes here because | |
636 | * of OOM. TODO: reserve one buffer with single page pinned | |
637 | * for providing forward progress guarantee. | |
638 | */ | |
639 | if (unlikely(!mapped_bytes)) { | |
640 | blk_mq_requeue_request(req, false); | |
641 | blk_mq_delay_kick_requeue_list(req->q, | |
642 | UBLK_REQUEUE_DELAY_MS); | |
643 | return; | |
644 | } | |
645 | ||
646 | ublk_get_iod(ubq, req->tag)->nr_sectors = | |
647 | mapped_bytes >> 9; | |
648 | } | |
649 | ||
650 | /* mark this cmd owned by ublksrv */ | |
651 | io->flags |= UBLK_IO_FLAG_OWNED_BY_SRV; | |
652 | ||
653 | /* | |
654 | * clear ACTIVE since we are done with this sqe/cmd slot | |
655 | * We can only accept io cmd in case of being not active. | |
656 | */ | |
657 | io->flags &= ~UBLK_IO_FLAG_ACTIVE; | |
658 | ||
659 | /* tell ublksrv one io request is coming */ | |
660 | io_uring_cmd_done(io->cmd, UBLK_IO_RES_OK, 0); | |
661 | } | |
662 | ||
0edb3696 ML |
663 | static void ublk_rq_task_work_cb(struct io_uring_cmd *cmd) |
664 | { | |
665 | struct ublk_uring_cmd_pdu *pdu = ublk_get_uring_cmd_pdu(cmd); | |
666 | ||
667 | __ublk_rq_task_work(pdu->req); | |
668 | } | |
669 | ||
670 | static void ublk_rq_task_work_fn(struct callback_head *work) | |
671 | { | |
672 | struct ublk_rq_data *data = container_of(work, | |
673 | struct ublk_rq_data, work); | |
674 | struct request *req = blk_mq_rq_from_pdu(data); | |
675 | ||
676 | __ublk_rq_task_work(req); | |
677 | } | |
678 | ||
71f28f31 ML |
679 | static blk_status_t ublk_queue_rq(struct blk_mq_hw_ctx *hctx, |
680 | const struct blk_mq_queue_data *bd) | |
681 | { | |
682 | struct ublk_queue *ubq = hctx->driver_data; | |
683 | struct request *rq = bd->rq; | |
71f28f31 ML |
684 | blk_status_t res; |
685 | ||
686 | /* fill iod to slot in io cmd buffer */ | |
687 | res = ublk_setup_iod(ubq, rq); | |
688 | if (unlikely(res != BLK_STS_OK)) | |
689 | return BLK_STS_IOERR; | |
690 | ||
691 | blk_mq_start_request(bd->rq); | |
692 | ||
693 | if (unlikely(ubq_daemon_is_dying(ubq))) { | |
0edb3696 | 694 | fail: |
71f28f31 ML |
695 | mod_delayed_work(system_wq, &ubq->dev->monitor_work, 0); |
696 | return BLK_STS_IOERR; | |
697 | } | |
698 | ||
0edb3696 ML |
699 | if (ublk_can_use_task_work(ubq)) { |
700 | struct ublk_rq_data *data = blk_mq_rq_to_pdu(rq); | |
701 | enum task_work_notify_mode notify_mode = bd->last ? | |
702 | TWA_SIGNAL_NO_IPI : TWA_NONE; | |
703 | ||
704 | if (task_work_add(ubq->ubq_daemon, &data->work, notify_mode)) | |
705 | goto fail; | |
706 | } else { | |
707 | struct io_uring_cmd *cmd = ubq->ios[rq->tag].cmd; | |
708 | struct ublk_uring_cmd_pdu *pdu = ublk_get_uring_cmd_pdu(cmd); | |
709 | ||
710 | pdu->req = rq; | |
711 | io_uring_cmd_complete_in_task(cmd, ublk_rq_task_work_cb); | |
712 | } | |
71f28f31 ML |
713 | |
714 | return BLK_STS_OK; | |
715 | } | |
716 | ||
0edb3696 ML |
717 | static void ublk_commit_rqs(struct blk_mq_hw_ctx *hctx) |
718 | { | |
719 | struct ublk_queue *ubq = hctx->driver_data; | |
720 | ||
721 | if (ublk_can_use_task_work(ubq)) | |
722 | __set_notify_signal(ubq->ubq_daemon); | |
723 | } | |
71f28f31 ML |
724 | |
725 | static int ublk_init_hctx(struct blk_mq_hw_ctx *hctx, void *driver_data, | |
726 | unsigned int hctx_idx) | |
727 | { | |
cebbe577 | 728 | struct ublk_device *ub = driver_data; |
71f28f31 ML |
729 | struct ublk_queue *ubq = ublk_get_queue(ub, hctx->queue_num); |
730 | ||
731 | hctx->driver_data = ubq; | |
732 | return 0; | |
733 | } | |
734 | ||
0edb3696 ML |
735 | static int ublk_init_rq(struct blk_mq_tag_set *set, struct request *req, |
736 | unsigned int hctx_idx, unsigned int numa_node) | |
737 | { | |
738 | struct ublk_rq_data *data = blk_mq_rq_to_pdu(req); | |
739 | ||
740 | init_task_work(&data->work, ublk_rq_task_work_fn); | |
741 | return 0; | |
742 | } | |
743 | ||
71f28f31 ML |
744 | static const struct blk_mq_ops ublk_mq_ops = { |
745 | .queue_rq = ublk_queue_rq, | |
0edb3696 | 746 | .commit_rqs = ublk_commit_rqs, |
71f28f31 | 747 | .init_hctx = ublk_init_hctx, |
0edb3696 | 748 | .init_request = ublk_init_rq, |
71f28f31 ML |
749 | }; |
750 | ||
751 | static int ublk_ch_open(struct inode *inode, struct file *filp) | |
752 | { | |
753 | struct ublk_device *ub = container_of(inode->i_cdev, | |
754 | struct ublk_device, cdev); | |
755 | ||
fa362045 CH |
756 | if (test_and_set_bit(UB_STATE_OPEN, &ub->state)) |
757 | return -EBUSY; | |
758 | filp->private_data = ub; | |
759 | return 0; | |
71f28f31 ML |
760 | } |
761 | ||
762 | static int ublk_ch_release(struct inode *inode, struct file *filp) | |
763 | { | |
764 | struct ublk_device *ub = filp->private_data; | |
765 | ||
fa362045 | 766 | clear_bit(UB_STATE_OPEN, &ub->state); |
71f28f31 ML |
767 | return 0; |
768 | } | |
769 | ||
770 | /* map pre-allocated per-queue cmd buffer to ublksrv daemon */ | |
771 | static int ublk_ch_mmap(struct file *filp, struct vm_area_struct *vma) | |
772 | { | |
773 | struct ublk_device *ub = filp->private_data; | |
774 | size_t sz = vma->vm_end - vma->vm_start; | |
775 | unsigned max_sz = UBLK_MAX_QUEUE_DEPTH * sizeof(struct ublksrv_io_desc); | |
776 | unsigned long pfn, end, phys_off = vma->vm_pgoff << PAGE_SHIFT; | |
777 | int q_id, ret = 0; | |
778 | ||
e94eb459 | 779 | spin_lock(&ub->mm_lock); |
71f28f31 ML |
780 | if (!ub->mm) |
781 | ub->mm = current->mm; | |
782 | if (current->mm != ub->mm) | |
783 | ret = -EINVAL; | |
e94eb459 | 784 | spin_unlock(&ub->mm_lock); |
71f28f31 ML |
785 | |
786 | if (ret) | |
787 | return ret; | |
788 | ||
789 | if (vma->vm_flags & VM_WRITE) | |
790 | return -EPERM; | |
791 | ||
792 | end = UBLKSRV_CMD_BUF_OFFSET + ub->dev_info.nr_hw_queues * max_sz; | |
793 | if (phys_off < UBLKSRV_CMD_BUF_OFFSET || phys_off >= end) | |
794 | return -EINVAL; | |
795 | ||
796 | q_id = (phys_off - UBLKSRV_CMD_BUF_OFFSET) / max_sz; | |
797 | pr_devel("%s: qid %d, pid %d, addr %lx pg_off %lx sz %lu\n", | |
798 | __func__, q_id, current->pid, vma->vm_start, | |
799 | phys_off, (unsigned long)sz); | |
800 | ||
801 | if (sz != ublk_queue_cmd_buf_size(ub, q_id)) | |
802 | return -EINVAL; | |
803 | ||
804 | pfn = virt_to_phys(ublk_queue_cmd_buf(ub, q_id)) >> PAGE_SHIFT; | |
805 | return remap_pfn_range(vma, vma->vm_start, pfn, sz, vma->vm_page_prot); | |
806 | } | |
807 | ||
808 | static void ublk_commit_completion(struct ublk_device *ub, | |
809 | struct ublksrv_io_cmd *ub_cmd) | |
810 | { | |
811 | u32 qid = ub_cmd->q_id, tag = ub_cmd->tag; | |
812 | struct ublk_queue *ubq = ublk_get_queue(ub, qid); | |
813 | struct ublk_io *io = &ubq->ios[tag]; | |
814 | struct request *req; | |
815 | ||
816 | /* now this cmd slot is owned by nbd driver */ | |
817 | io->flags &= ~UBLK_IO_FLAG_OWNED_BY_SRV; | |
818 | io->res = ub_cmd->result; | |
819 | ||
820 | /* find the io request and complete */ | |
821 | req = blk_mq_tag_to_rq(ub->tag_set.tags[qid], tag); | |
822 | ||
823 | if (req && likely(!blk_should_fake_timeout(req->q))) | |
824 | ublk_complete_rq(req); | |
825 | } | |
826 | ||
827 | /* | |
828 | * When ->ubq_daemon is exiting, either new request is ended immediately, | |
829 | * or any queued io command is drained, so it is safe to abort queue | |
830 | * lockless | |
831 | */ | |
832 | static void ublk_abort_queue(struct ublk_device *ub, struct ublk_queue *ubq) | |
833 | { | |
834 | int i; | |
835 | ||
836 | if (!ublk_get_device(ub)) | |
837 | return; | |
838 | ||
839 | for (i = 0; i < ubq->q_depth; i++) { | |
840 | struct ublk_io *io = &ubq->ios[i]; | |
841 | ||
842 | if (!(io->flags & UBLK_IO_FLAG_ACTIVE)) { | |
843 | struct request *rq; | |
844 | ||
845 | /* | |
846 | * Either we fail the request or ublk_rq_task_work_fn | |
847 | * will do it | |
848 | */ | |
849 | rq = blk_mq_tag_to_rq(ub->tag_set.tags[ubq->q_id], i); | |
850 | if (rq) | |
851 | __ublk_fail_req(io, rq); | |
852 | } | |
853 | } | |
854 | ublk_put_device(ub); | |
855 | } | |
856 | ||
857 | static void ublk_daemon_monitor_work(struct work_struct *work) | |
858 | { | |
859 | struct ublk_device *ub = | |
860 | container_of(work, struct ublk_device, monitor_work.work); | |
861 | int i; | |
862 | ||
863 | for (i = 0; i < ub->dev_info.nr_hw_queues; i++) { | |
864 | struct ublk_queue *ubq = ublk_get_queue(ub, i); | |
865 | ||
866 | if (ubq_daemon_is_dying(ubq)) { | |
867 | schedule_work(&ub->stop_work); | |
868 | ||
869 | /* abort queue is for making forward progress */ | |
870 | ublk_abort_queue(ub, ubq); | |
871 | } | |
872 | } | |
873 | ||
874 | /* | |
875 | * We can't schedule monitor work after ublk_remove() is started. | |
876 | * | |
877 | * No need ub->mutex, monitor work are canceled after state is marked | |
878 | * as DEAD, so DEAD state is observed reliably. | |
879 | */ | |
880 | if (ub->dev_info.state != UBLK_S_DEV_DEAD) | |
881 | schedule_delayed_work(&ub->monitor_work, | |
882 | UBLK_DAEMON_MONITOR_PERIOD); | |
883 | } | |
884 | ||
a8ce5f52 ML |
885 | static inline bool ublk_queue_ready(struct ublk_queue *ubq) |
886 | { | |
887 | return ubq->nr_io_ready == ubq->q_depth; | |
888 | } | |
889 | ||
71f28f31 ML |
890 | static void ublk_cancel_queue(struct ublk_queue *ubq) |
891 | { | |
892 | int i; | |
893 | ||
a8ce5f52 ML |
894 | if (!ublk_queue_ready(ubq)) |
895 | return; | |
896 | ||
71f28f31 ML |
897 | for (i = 0; i < ubq->q_depth; i++) { |
898 | struct ublk_io *io = &ubq->ios[i]; | |
899 | ||
900 | if (io->flags & UBLK_IO_FLAG_ACTIVE) | |
901 | io_uring_cmd_done(io->cmd, UBLK_IO_RES_ABORT, 0); | |
902 | } | |
a8ce5f52 ML |
903 | |
904 | /* all io commands are canceled */ | |
905 | ubq->nr_io_ready = 0; | |
71f28f31 ML |
906 | } |
907 | ||
908 | /* Cancel all pending commands, must be called after del_gendisk() returns */ | |
909 | static void ublk_cancel_dev(struct ublk_device *ub) | |
910 | { | |
911 | int i; | |
912 | ||
913 | for (i = 0; i < ub->dev_info.nr_hw_queues; i++) | |
914 | ublk_cancel_queue(ublk_get_queue(ub, i)); | |
915 | } | |
916 | ||
917 | static void ublk_stop_dev(struct ublk_device *ub) | |
918 | { | |
919 | mutex_lock(&ub->mutex); | |
6d9e6dfd | 920 | if (ub->dev_info.state != UBLK_S_DEV_LIVE) |
71f28f31 ML |
921 | goto unlock; |
922 | ||
923 | del_gendisk(ub->ub_disk); | |
924 | ub->dev_info.state = UBLK_S_DEV_DEAD; | |
925 | ub->dev_info.ublksrv_pid = -1; | |
6d9e6dfd CH |
926 | put_disk(ub->ub_disk); |
927 | ub->ub_disk = NULL; | |
71f28f31 | 928 | unlock: |
a8ce5f52 | 929 | ublk_cancel_dev(ub); |
71f28f31 ML |
930 | mutex_unlock(&ub->mutex); |
931 | cancel_delayed_work_sync(&ub->monitor_work); | |
932 | } | |
933 | ||
71f28f31 ML |
934 | /* device can only be started after all IOs are ready */ |
935 | static void ublk_mark_io_ready(struct ublk_device *ub, struct ublk_queue *ubq) | |
936 | { | |
937 | mutex_lock(&ub->mutex); | |
938 | ubq->nr_io_ready++; | |
939 | if (ublk_queue_ready(ubq)) { | |
940 | ubq->ubq_daemon = current; | |
941 | get_task_struct(ubq->ubq_daemon); | |
942 | ub->nr_queues_ready++; | |
943 | } | |
944 | if (ub->nr_queues_ready == ub->dev_info.nr_hw_queues) | |
945 | complete_all(&ub->completion); | |
946 | mutex_unlock(&ub->mutex); | |
947 | } | |
948 | ||
949 | static int ublk_ch_uring_cmd(struct io_uring_cmd *cmd, unsigned int issue_flags) | |
950 | { | |
951 | struct ublksrv_io_cmd *ub_cmd = (struct ublksrv_io_cmd *)cmd->cmd; | |
952 | struct ublk_device *ub = cmd->file->private_data; | |
953 | struct ublk_queue *ubq; | |
954 | struct ublk_io *io; | |
955 | u32 cmd_op = cmd->cmd_op; | |
956 | unsigned tag = ub_cmd->tag; | |
957 | int ret = -EINVAL; | |
958 | ||
959 | pr_devel("%s: received: cmd op %d queue %d tag %d result %d\n", | |
960 | __func__, cmd->cmd_op, ub_cmd->q_id, tag, | |
961 | ub_cmd->result); | |
962 | ||
963 | if (!(issue_flags & IO_URING_F_SQE128)) | |
964 | goto out; | |
965 | ||
966 | if (ub_cmd->q_id >= ub->dev_info.nr_hw_queues) | |
967 | goto out; | |
968 | ||
969 | ubq = ublk_get_queue(ub, ub_cmd->q_id); | |
970 | if (!ubq || ub_cmd->q_id != ubq->q_id) | |
971 | goto out; | |
972 | ||
973 | if (ubq->ubq_daemon && ubq->ubq_daemon != current) | |
974 | goto out; | |
975 | ||
976 | if (tag >= ubq->q_depth) | |
977 | goto out; | |
978 | ||
979 | io = &ubq->ios[tag]; | |
980 | ||
981 | /* there is pending io cmd, something must be wrong */ | |
982 | if (io->flags & UBLK_IO_FLAG_ACTIVE) { | |
983 | ret = -EBUSY; | |
984 | goto out; | |
985 | } | |
986 | ||
987 | switch (cmd_op) { | |
988 | case UBLK_IO_FETCH_REQ: | |
989 | /* UBLK_IO_FETCH_REQ is only allowed before queue is setup */ | |
990 | if (ublk_queue_ready(ubq)) { | |
991 | ret = -EBUSY; | |
992 | goto out; | |
993 | } | |
994 | /* | |
995 | * The io is being handled by server, so COMMIT_RQ is expected | |
996 | * instead of FETCH_REQ | |
997 | */ | |
998 | if (io->flags & UBLK_IO_FLAG_OWNED_BY_SRV) | |
999 | goto out; | |
1000 | /* FETCH_RQ has to provide IO buffer */ | |
1001 | if (!ub_cmd->addr) | |
1002 | goto out; | |
1003 | io->cmd = cmd; | |
1004 | io->flags |= UBLK_IO_FLAG_ACTIVE; | |
1005 | io->addr = ub_cmd->addr; | |
1006 | ||
1007 | ublk_mark_io_ready(ub, ubq); | |
1008 | break; | |
1009 | case UBLK_IO_COMMIT_AND_FETCH_REQ: | |
1010 | /* FETCH_RQ has to provide IO buffer */ | |
1011 | if (!ub_cmd->addr) | |
1012 | goto out; | |
1013 | if (!(io->flags & UBLK_IO_FLAG_OWNED_BY_SRV)) | |
1014 | goto out; | |
1015 | io->addr = ub_cmd->addr; | |
1016 | io->flags |= UBLK_IO_FLAG_ACTIVE; | |
1017 | io->cmd = cmd; | |
1018 | ublk_commit_completion(ub, ub_cmd); | |
1019 | break; | |
1020 | default: | |
1021 | goto out; | |
1022 | } | |
1023 | return -EIOCBQUEUED; | |
1024 | ||
1025 | out: | |
71f28f31 ML |
1026 | io_uring_cmd_done(cmd, ret, 0); |
1027 | pr_devel("%s: complete: cmd op %d, tag %d ret %x io_flags %x\n", | |
1028 | __func__, cmd_op, tag, ret, io->flags); | |
1029 | return -EIOCBQUEUED; | |
1030 | } | |
1031 | ||
1032 | static const struct file_operations ublk_ch_fops = { | |
1033 | .owner = THIS_MODULE, | |
1034 | .open = ublk_ch_open, | |
1035 | .release = ublk_ch_release, | |
1036 | .llseek = no_llseek, | |
1037 | .uring_cmd = ublk_ch_uring_cmd, | |
1038 | .mmap = ublk_ch_mmap, | |
1039 | }; | |
1040 | ||
1041 | static void ublk_deinit_queue(struct ublk_device *ub, int q_id) | |
1042 | { | |
1043 | int size = ublk_queue_cmd_buf_size(ub, q_id); | |
1044 | struct ublk_queue *ubq = ublk_get_queue(ub, q_id); | |
1045 | ||
1046 | if (ubq->ubq_daemon) | |
1047 | put_task_struct(ubq->ubq_daemon); | |
1048 | if (ubq->io_cmd_buf) | |
1049 | free_pages((unsigned long)ubq->io_cmd_buf, get_order(size)); | |
1050 | } | |
1051 | ||
1052 | static int ublk_init_queue(struct ublk_device *ub, int q_id) | |
1053 | { | |
1054 | struct ublk_queue *ubq = ublk_get_queue(ub, q_id); | |
1055 | gfp_t gfp_flags = GFP_KERNEL | __GFP_ZERO; | |
1056 | void *ptr; | |
1057 | int size; | |
1058 | ||
6d8c5afc | 1059 | ubq->flags = ub->dev_info.flags; |
71f28f31 ML |
1060 | ubq->q_id = q_id; |
1061 | ubq->q_depth = ub->dev_info.queue_depth; | |
1062 | size = ublk_queue_cmd_buf_size(ub, q_id); | |
1063 | ||
1064 | ptr = (void *) __get_free_pages(gfp_flags, get_order(size)); | |
1065 | if (!ptr) | |
1066 | return -ENOMEM; | |
1067 | ||
1068 | ubq->io_cmd_buf = ptr; | |
1069 | ubq->dev = ub; | |
1070 | return 0; | |
1071 | } | |
1072 | ||
1073 | static void ublk_deinit_queues(struct ublk_device *ub) | |
1074 | { | |
1075 | int nr_queues = ub->dev_info.nr_hw_queues; | |
1076 | int i; | |
1077 | ||
1078 | if (!ub->__queues) | |
1079 | return; | |
1080 | ||
1081 | for (i = 0; i < nr_queues; i++) | |
1082 | ublk_deinit_queue(ub, i); | |
1083 | kfree(ub->__queues); | |
1084 | } | |
1085 | ||
1086 | static int ublk_init_queues(struct ublk_device *ub) | |
1087 | { | |
1088 | int nr_queues = ub->dev_info.nr_hw_queues; | |
1089 | int depth = ub->dev_info.queue_depth; | |
1090 | int ubq_size = sizeof(struct ublk_queue) + depth * sizeof(struct ublk_io); | |
1091 | int i, ret = -ENOMEM; | |
1092 | ||
1093 | ub->queue_size = ubq_size; | |
1094 | ub->__queues = kcalloc(nr_queues, ubq_size, GFP_KERNEL); | |
1095 | if (!ub->__queues) | |
1096 | return ret; | |
1097 | ||
1098 | for (i = 0; i < nr_queues; i++) { | |
1099 | if (ublk_init_queue(ub, i)) | |
1100 | goto fail; | |
1101 | } | |
1102 | ||
1103 | init_completion(&ub->completion); | |
1104 | return 0; | |
1105 | ||
1106 | fail: | |
1107 | ublk_deinit_queues(ub); | |
1108 | return ret; | |
1109 | } | |
1110 | ||
fa9482e0 | 1111 | static int ublk_alloc_dev_number(struct ublk_device *ub, int idx) |
71f28f31 ML |
1112 | { |
1113 | int i = idx; | |
1114 | int err; | |
1115 | ||
1116 | spin_lock(&ublk_idr_lock); | |
1117 | /* allocate id, if @id >= 0, we're requesting that specific id */ | |
1118 | if (i >= 0) { | |
1119 | err = idr_alloc(&ublk_index_idr, ub, i, i + 1, GFP_NOWAIT); | |
1120 | if (err == -ENOSPC) | |
1121 | err = -EEXIST; | |
1122 | } else { | |
1123 | err = idr_alloc(&ublk_index_idr, ub, 0, 0, GFP_NOWAIT); | |
1124 | } | |
1125 | spin_unlock(&ublk_idr_lock); | |
1126 | ||
1127 | if (err >= 0) | |
1128 | ub->ub_number = err; | |
1129 | ||
1130 | return err; | |
1131 | } | |
1132 | ||
fa9482e0 | 1133 | static void ublk_free_dev_number(struct ublk_device *ub) |
71f28f31 ML |
1134 | { |
1135 | spin_lock(&ublk_idr_lock); | |
1136 | idr_remove(&ublk_index_idr, ub->ub_number); | |
1137 | wake_up_all(&ublk_idr_wq); | |
1138 | spin_unlock(&ublk_idr_lock); | |
71f28f31 ML |
1139 | } |
1140 | ||
1141 | static void ublk_cdev_rel(struct device *dev) | |
1142 | { | |
1143 | struct ublk_device *ub = container_of(dev, struct ublk_device, cdev_dev); | |
1144 | ||
71f28f31 | 1145 | blk_mq_free_tag_set(&ub->tag_set); |
71f28f31 | 1146 | ublk_deinit_queues(ub); |
fa9482e0 CH |
1147 | ublk_free_dev_number(ub); |
1148 | mutex_destroy(&ub->mutex); | |
1149 | kfree(ub); | |
71f28f31 ML |
1150 | } |
1151 | ||
1152 | static int ublk_add_chdev(struct ublk_device *ub) | |
1153 | { | |
1154 | struct device *dev = &ub->cdev_dev; | |
1155 | int minor = ub->ub_number; | |
1156 | int ret; | |
1157 | ||
1158 | dev->parent = ublk_misc.this_device; | |
1159 | dev->devt = MKDEV(MAJOR(ublk_chr_devt), minor); | |
1160 | dev->class = ublk_chr_class; | |
1161 | dev->release = ublk_cdev_rel; | |
1162 | device_initialize(dev); | |
1163 | ||
1164 | ret = dev_set_name(dev, "ublkc%d", minor); | |
1165 | if (ret) | |
1166 | goto fail; | |
1167 | ||
1168 | cdev_init(&ub->cdev, &ublk_ch_fops); | |
1169 | ret = cdev_device_add(&ub->cdev, dev); | |
1170 | if (ret) | |
1171 | goto fail; | |
1172 | return 0; | |
1173 | fail: | |
1174 | put_device(dev); | |
1175 | return ret; | |
1176 | } | |
1177 | ||
1178 | static void ublk_stop_work_fn(struct work_struct *work) | |
1179 | { | |
1180 | struct ublk_device *ub = | |
1181 | container_of(work, struct ublk_device, stop_work); | |
1182 | ||
1183 | ublk_stop_dev(ub); | |
1184 | } | |
1185 | ||
4bf9cbf3 | 1186 | /* align max io buffer size with PAGE_SIZE */ |
6d9e6dfd | 1187 | static void ublk_align_max_io_size(struct ublk_device *ub) |
71f28f31 | 1188 | { |
4bf9cbf3 | 1189 | unsigned int max_io_bytes = ub->dev_info.max_io_buf_bytes; |
71f28f31 | 1190 | |
4bf9cbf3 ML |
1191 | ub->dev_info.max_io_buf_bytes = |
1192 | round_down(max_io_bytes, PAGE_SIZE); | |
71f28f31 ML |
1193 | } |
1194 | ||
fa9482e0 | 1195 | static int ublk_add_tag_set(struct ublk_device *ub) |
71f28f31 | 1196 | { |
71f28f31 ML |
1197 | ub->tag_set.ops = &ublk_mq_ops; |
1198 | ub->tag_set.nr_hw_queues = ub->dev_info.nr_hw_queues; | |
1199 | ub->tag_set.queue_depth = ub->dev_info.queue_depth; | |
1200 | ub->tag_set.numa_node = NUMA_NO_NODE; | |
0edb3696 | 1201 | ub->tag_set.cmd_size = sizeof(struct ublk_rq_data); |
71f28f31 ML |
1202 | ub->tag_set.flags = BLK_MQ_F_SHOULD_MERGE; |
1203 | ub->tag_set.driver_data = ub; | |
fa9482e0 | 1204 | return blk_mq_alloc_tag_set(&ub->tag_set); |
71f28f31 ML |
1205 | } |
1206 | ||
1207 | static void ublk_remove(struct ublk_device *ub) | |
1208 | { | |
34d8f2be CH |
1209 | ublk_stop_dev(ub); |
1210 | cancel_work_sync(&ub->stop_work); | |
71f28f31 ML |
1211 | cdev_device_del(&ub->cdev, &ub->cdev_dev); |
1212 | put_device(&ub->cdev_dev); | |
1213 | } | |
1214 | ||
1215 | static struct ublk_device *ublk_get_device_from_id(int idx) | |
1216 | { | |
1217 | struct ublk_device *ub = NULL; | |
1218 | ||
1219 | if (idx < 0) | |
1220 | return NULL; | |
1221 | ||
1222 | spin_lock(&ublk_idr_lock); | |
1223 | ub = idr_find(&ublk_index_idr, idx); | |
1224 | if (ub) | |
1225 | ub = ublk_get_device(ub); | |
1226 | spin_unlock(&ublk_idr_lock); | |
1227 | ||
1228 | return ub; | |
1229 | } | |
1230 | ||
34d8f2be | 1231 | static int ublk_ctrl_start_dev(struct io_uring_cmd *cmd) |
71f28f31 ML |
1232 | { |
1233 | struct ublksrv_ctrl_cmd *header = (struct ublksrv_ctrl_cmd *)cmd->cmd; | |
71f28f31 | 1234 | int ublksrv_pid = (int)header->data[0]; |
34d8f2be | 1235 | struct ublk_device *ub; |
6d9e6dfd | 1236 | struct gendisk *disk; |
34d8f2be | 1237 | int ret = -EINVAL; |
71f28f31 ML |
1238 | |
1239 | if (ublksrv_pid <= 0) | |
34d8f2be CH |
1240 | return -EINVAL; |
1241 | ||
1242 | ub = ublk_get_device_from_id(header->dev_id); | |
1243 | if (!ub) | |
1244 | return -EINVAL; | |
71f28f31 ML |
1245 | |
1246 | wait_for_completion_interruptible(&ub->completion); | |
1247 | ||
1248 | schedule_delayed_work(&ub->monitor_work, UBLK_DAEMON_MONITOR_PERIOD); | |
1249 | ||
1250 | mutex_lock(&ub->mutex); | |
6d9e6dfd CH |
1251 | if (ub->dev_info.state == UBLK_S_DEV_LIVE || |
1252 | test_bit(UB_STATE_USED, &ub->state)) { | |
71f28f31 | 1253 | ret = -EEXIST; |
34d8f2be | 1254 | goto out_unlock; |
71f28f31 | 1255 | } |
71f28f31 | 1256 | |
6d9e6dfd CH |
1257 | disk = blk_mq_alloc_disk(&ub->tag_set, ub); |
1258 | if (IS_ERR(disk)) { | |
1259 | ret = PTR_ERR(disk); | |
1260 | goto out_unlock; | |
34d8f2be | 1261 | } |
6d9e6dfd CH |
1262 | sprintf(disk->disk_name, "ublkb%d", ub->ub_number); |
1263 | disk->fops = &ub_fops; | |
1264 | disk->private_data = ub; | |
1265 | ||
34d8f2be | 1266 | ub->dev_info.ublksrv_pid = ublksrv_pid; |
6d9e6dfd | 1267 | ub->ub_disk = disk; |
0aa73170 ML |
1268 | |
1269 | ret = ublk_apply_params(ub); | |
1270 | if (ret) | |
1271 | goto out_put_disk; | |
1272 | ||
6d9e6dfd CH |
1273 | get_device(&ub->cdev_dev); |
1274 | ret = add_disk(disk); | |
1275 | if (ret) { | |
93d71ec8 ML |
1276 | /* |
1277 | * Has to drop the reference since ->free_disk won't be | |
1278 | * called in case of add_disk failure. | |
1279 | */ | |
1280 | ublk_put_device(ub); | |
0aa73170 | 1281 | goto out_put_disk; |
6d9e6dfd CH |
1282 | } |
1283 | set_bit(UB_STATE_USED, &ub->state); | |
34d8f2be | 1284 | ub->dev_info.state = UBLK_S_DEV_LIVE; |
0aa73170 ML |
1285 | out_put_disk: |
1286 | if (ret) | |
1287 | put_disk(disk); | |
34d8f2be CH |
1288 | out_unlock: |
1289 | mutex_unlock(&ub->mutex); | |
1290 | ublk_put_device(ub); | |
71f28f31 ML |
1291 | return ret; |
1292 | } | |
1293 | ||
71f28f31 ML |
1294 | static int ublk_ctrl_get_queue_affinity(struct io_uring_cmd *cmd) |
1295 | { | |
1296 | struct ublksrv_ctrl_cmd *header = (struct ublksrv_ctrl_cmd *)cmd->cmd; | |
1297 | void __user *argp = (void __user *)(unsigned long)header->addr; | |
71f28f31 | 1298 | struct ublk_device *ub; |
c50061f0 | 1299 | cpumask_var_t cpumask; |
71f28f31 ML |
1300 | unsigned long queue; |
1301 | unsigned int retlen; | |
c50061f0 | 1302 | unsigned int i; |
f2450f8a | 1303 | int ret = -EINVAL; |
34d8f2be CH |
1304 | |
1305 | if (header->len * BITS_PER_BYTE < nr_cpu_ids) | |
1306 | return -EINVAL; | |
1307 | if (header->len & (sizeof(unsigned long)-1)) | |
1308 | return -EINVAL; | |
1309 | if (!header->addr) | |
1310 | return -EINVAL; | |
71f28f31 ML |
1311 | |
1312 | ub = ublk_get_device_from_id(header->dev_id); | |
1313 | if (!ub) | |
c50061f0 | 1314 | return -EINVAL; |
71f28f31 | 1315 | |
71f28f31 ML |
1316 | queue = header->data[0]; |
1317 | if (queue >= ub->dev_info.nr_hw_queues) | |
c50061f0 | 1318 | goto out_put_device; |
71f28f31 | 1319 | |
c50061f0 CH |
1320 | ret = -ENOMEM; |
1321 | if (!zalloc_cpumask_var(&cpumask, GFP_KERNEL)) | |
1322 | goto out_put_device; | |
1323 | ||
1324 | for_each_possible_cpu(i) { | |
1325 | if (ub->tag_set.map[HCTX_TYPE_DEFAULT].mq_map[i] == queue) | |
1326 | cpumask_set_cpu(i, cpumask); | |
71f28f31 | 1327 | } |
c50061f0 CH |
1328 | |
1329 | ret = -EFAULT; | |
1330 | retlen = min_t(unsigned short, header->len, cpumask_size()); | |
1331 | if (copy_to_user(argp, cpumask, retlen)) | |
1332 | goto out_free_cpumask; | |
1333 | if (retlen != header->len && | |
1334 | clear_user(argp + retlen, header->len - retlen)) | |
1335 | goto out_free_cpumask; | |
1336 | ||
71f28f31 | 1337 | ret = 0; |
c50061f0 CH |
1338 | out_free_cpumask: |
1339 | free_cpumask_var(cpumask); | |
1340 | out_put_device: | |
1341 | ublk_put_device(ub); | |
71f28f31 ML |
1342 | return ret; |
1343 | } | |
1344 | ||
34d8f2be | 1345 | static inline void ublk_dump_dev_info(struct ublksrv_ctrl_dev_info *info) |
71f28f31 | 1346 | { |
34d8f2be | 1347 | pr_devel("%s: dev id %d flags %llx\n", __func__, |
6d8c5afc | 1348 | info->dev_id, info->flags); |
4bf9cbf3 ML |
1349 | pr_devel("\t nr_hw_queues %d queue_depth %d\n", |
1350 | info->nr_hw_queues, info->queue_depth); | |
34d8f2be CH |
1351 | } |
1352 | ||
1353 | static int ublk_ctrl_add_dev(struct io_uring_cmd *cmd) | |
1354 | { | |
1355 | struct ublksrv_ctrl_cmd *header = (struct ublksrv_ctrl_cmd *)cmd->cmd; | |
1356 | void __user *argp = (void __user *)(unsigned long)header->addr; | |
1357 | struct ublksrv_ctrl_dev_info info; | |
71f28f31 | 1358 | struct ublk_device *ub; |
34d8f2be CH |
1359 | int ret = -EINVAL; |
1360 | ||
1361 | if (header->len < sizeof(info) || !header->addr) | |
1362 | return -EINVAL; | |
1363 | if (header->queue_id != (u16)-1) { | |
1364 | pr_warn("%s: queue_id is wrong %x\n", | |
1365 | __func__, header->queue_id); | |
1366 | return -EINVAL; | |
1367 | } | |
1368 | if (copy_from_user(&info, argp, sizeof(info))) | |
1369 | return -EFAULT; | |
1370 | ublk_dump_dev_info(&info); | |
1371 | if (header->dev_id != info.dev_id) { | |
1372 | pr_warn("%s: dev id not match %u %u\n", | |
1373 | __func__, header->dev_id, info.dev_id); | |
1374 | return -EINVAL; | |
1375 | } | |
71f28f31 ML |
1376 | |
1377 | ret = mutex_lock_killable(&ublk_ctl_mutex); | |
1378 | if (ret) | |
1379 | return ret; | |
1380 | ||
cfee7e4d CH |
1381 | ret = -ENOMEM; |
1382 | ub = kzalloc(sizeof(*ub), GFP_KERNEL); | |
1383 | if (!ub) | |
1384 | goto out_unlock; | |
fa9482e0 CH |
1385 | mutex_init(&ub->mutex); |
1386 | spin_lock_init(&ub->mm_lock); | |
1387 | INIT_WORK(&ub->stop_work, ublk_stop_work_fn); | |
1388 | INIT_DELAYED_WORK(&ub->monitor_work, ublk_daemon_monitor_work); | |
cfee7e4d | 1389 | |
fa9482e0 CH |
1390 | ret = ublk_alloc_dev_number(ub, header->dev_id); |
1391 | if (ret < 0) | |
1392 | goto out_free_ub; | |
71f28f31 | 1393 | |
34d8f2be | 1394 | memcpy(&ub->dev_info, &info, sizeof(info)); |
71f28f31 | 1395 | |
34d8f2be CH |
1396 | /* update device id */ |
1397 | ub->dev_info.dev_id = ub->ub_number; | |
1398 | ||
6d8c5afc ML |
1399 | /* |
1400 | * 64bit flags will be copied back to userspace as feature | |
1401 | * negotiation result, so have to clear flags which driver | |
1402 | * doesn't support yet, then userspace can get correct flags | |
1403 | * (features) to handle. | |
1404 | */ | |
1405 | ub->dev_info.flags &= UBLK_F_ALL; | |
1406 | ||
fa9482e0 | 1407 | /* We are not ready to support zero copy */ |
6d8c5afc | 1408 | ub->dev_info.flags &= ~UBLK_F_SUPPORT_ZERO_COPY; |
fa9482e0 | 1409 | |
fa9482e0 CH |
1410 | ub->dev_info.nr_hw_queues = min_t(unsigned int, |
1411 | ub->dev_info.nr_hw_queues, nr_cpu_ids); | |
1412 | ublk_align_max_io_size(ub); | |
1413 | ||
1414 | ret = ublk_init_queues(ub); | |
34d8f2be | 1415 | if (ret) |
fa9482e0 | 1416 | goto out_free_dev_number; |
34d8f2be | 1417 | |
fa9482e0 CH |
1418 | ret = ublk_add_tag_set(ub); |
1419 | if (ret) | |
1420 | goto out_deinit_queues; | |
1421 | ||
1422 | ret = -EFAULT; | |
1423 | if (copy_to_user(argp, &ub->dev_info, sizeof(info))) | |
1424 | goto out_free_tag_set; | |
1425 | ||
1426 | /* | |
1427 | * Add the char dev so that ublksrv daemon can be setup. | |
1428 | * ublk_add_chdev() will cleanup everything if it fails. | |
1429 | */ | |
1430 | ret = ublk_add_chdev(ub); | |
1431 | goto out_unlock; | |
1432 | ||
1433 | out_free_tag_set: | |
1434 | blk_mq_free_tag_set(&ub->tag_set); | |
1435 | out_deinit_queues: | |
1436 | ublk_deinit_queues(ub); | |
1437 | out_free_dev_number: | |
1438 | ublk_free_dev_number(ub); | |
1439 | out_free_ub: | |
1440 | mutex_destroy(&ub->mutex); | |
1441 | kfree(ub); | |
34d8f2be | 1442 | out_unlock: |
71f28f31 | 1443 | mutex_unlock(&ublk_ctl_mutex); |
71f28f31 ML |
1444 | return ret; |
1445 | } | |
1446 | ||
1447 | static inline bool ublk_idr_freed(int id) | |
1448 | { | |
1449 | void *ptr; | |
1450 | ||
1451 | spin_lock(&ublk_idr_lock); | |
1452 | ptr = idr_find(&ublk_index_idr, id); | |
1453 | spin_unlock(&ublk_idr_lock); | |
1454 | ||
1455 | return ptr == NULL; | |
1456 | } | |
1457 | ||
1458 | static int ublk_ctrl_del_dev(int idx) | |
1459 | { | |
1460 | struct ublk_device *ub; | |
1461 | int ret; | |
1462 | ||
1463 | ret = mutex_lock_killable(&ublk_ctl_mutex); | |
1464 | if (ret) | |
1465 | return ret; | |
1466 | ||
1467 | ub = ublk_get_device_from_id(idx); | |
1468 | if (ub) { | |
1469 | ublk_remove(ub); | |
1470 | ublk_put_device(ub); | |
1471 | ret = 0; | |
1472 | } else { | |
1473 | ret = -ENODEV; | |
1474 | } | |
1475 | ||
1476 | /* | |
1477 | * Wait until the idr is removed, then it can be reused after | |
1478 | * DEL_DEV command is returned. | |
1479 | */ | |
1480 | if (!ret) | |
1481 | wait_event(ublk_idr_wq, ublk_idr_freed(idx)); | |
1482 | mutex_unlock(&ublk_ctl_mutex); | |
1483 | ||
1484 | return ret; | |
1485 | } | |
1486 | ||
71f28f31 ML |
1487 | static inline void ublk_ctrl_cmd_dump(struct io_uring_cmd *cmd) |
1488 | { | |
1489 | struct ublksrv_ctrl_cmd *header = (struct ublksrv_ctrl_cmd *)cmd->cmd; | |
1490 | ||
1491 | pr_devel("%s: cmd_op %x, dev id %d qid %d data %llx buf %llx len %u\n", | |
1492 | __func__, cmd->cmd_op, header->dev_id, header->queue_id, | |
1493 | header->data[0], header->addr, header->len); | |
1494 | } | |
1495 | ||
34d8f2be | 1496 | static int ublk_ctrl_stop_dev(struct io_uring_cmd *cmd) |
71f28f31 ML |
1497 | { |
1498 | struct ublksrv_ctrl_cmd *header = (struct ublksrv_ctrl_cmd *)cmd->cmd; | |
34d8f2be | 1499 | struct ublk_device *ub; |
71f28f31 | 1500 | |
34d8f2be CH |
1501 | ub = ublk_get_device_from_id(header->dev_id); |
1502 | if (!ub) | |
1503 | return -EINVAL; | |
71f28f31 | 1504 | |
34d8f2be CH |
1505 | ublk_stop_dev(ub); |
1506 | cancel_work_sync(&ub->stop_work); | |
71f28f31 | 1507 | |
34d8f2be | 1508 | ublk_put_device(ub); |
71f28f31 ML |
1509 | return 0; |
1510 | } | |
1511 | ||
34d8f2be | 1512 | static int ublk_ctrl_get_dev_info(struct io_uring_cmd *cmd) |
71f28f31 ML |
1513 | { |
1514 | struct ublksrv_ctrl_cmd *header = (struct ublksrv_ctrl_cmd *)cmd->cmd; | |
1515 | void __user *argp = (void __user *)(unsigned long)header->addr; | |
71f28f31 | 1516 | struct ublk_device *ub; |
34d8f2be CH |
1517 | int ret = 0; |
1518 | ||
1519 | if (header->len < sizeof(struct ublksrv_ctrl_dev_info) || !header->addr) | |
1520 | return -EINVAL; | |
1521 | ||
1522 | ub = ublk_get_device_from_id(header->dev_id); | |
1523 | if (!ub) | |
1524 | return -EINVAL; | |
1525 | ||
1526 | if (copy_to_user(argp, &ub->dev_info, sizeof(ub->dev_info))) | |
1527 | ret = -EFAULT; | |
1528 | ublk_put_device(ub); | |
1529 | ||
1530 | return ret; | |
1531 | } | |
1532 | ||
0aa73170 ML |
1533 | static int ublk_ctrl_get_params(struct io_uring_cmd *cmd) |
1534 | { | |
1535 | struct ublksrv_ctrl_cmd *header = (struct ublksrv_ctrl_cmd *)cmd->cmd; | |
1536 | void __user *argp = (void __user *)(unsigned long)header->addr; | |
1537 | struct ublk_params_header ph; | |
1538 | struct ublk_device *ub; | |
1539 | int ret; | |
1540 | ||
1541 | if (header->len <= sizeof(ph) || !header->addr) | |
1542 | return -EINVAL; | |
1543 | ||
1544 | if (copy_from_user(&ph, argp, sizeof(ph))) | |
1545 | return -EFAULT; | |
1546 | ||
1547 | if (ph.len > header->len || !ph.len) | |
1548 | return -EINVAL; | |
1549 | ||
1550 | if (ph.len > sizeof(struct ublk_params)) | |
1551 | ph.len = sizeof(struct ublk_params); | |
1552 | ||
1553 | ub = ublk_get_device_from_id(header->dev_id); | |
1554 | if (!ub) | |
1555 | return -EINVAL; | |
1556 | ||
1557 | mutex_lock(&ub->mutex); | |
1558 | if (copy_to_user(argp, &ub->params, ph.len)) | |
1559 | ret = -EFAULT; | |
1560 | else | |
1561 | ret = 0; | |
1562 | mutex_unlock(&ub->mutex); | |
1563 | ||
1564 | ublk_put_device(ub); | |
1565 | return ret; | |
1566 | } | |
1567 | ||
1568 | static int ublk_ctrl_set_params(struct io_uring_cmd *cmd) | |
1569 | { | |
1570 | struct ublksrv_ctrl_cmd *header = (struct ublksrv_ctrl_cmd *)cmd->cmd; | |
1571 | void __user *argp = (void __user *)(unsigned long)header->addr; | |
1572 | struct ublk_params_header ph; | |
1573 | struct ublk_device *ub; | |
1574 | int ret = -EFAULT; | |
1575 | ||
1576 | if (header->len <= sizeof(ph) || !header->addr) | |
1577 | return -EINVAL; | |
1578 | ||
1579 | if (copy_from_user(&ph, argp, sizeof(ph))) | |
1580 | return -EFAULT; | |
1581 | ||
1582 | if (ph.len > header->len || !ph.len || !ph.types) | |
1583 | return -EINVAL; | |
1584 | ||
1585 | if (ph.len > sizeof(struct ublk_params)) | |
1586 | ph.len = sizeof(struct ublk_params); | |
1587 | ||
1588 | ub = ublk_get_device_from_id(header->dev_id); | |
1589 | if (!ub) | |
1590 | return -EINVAL; | |
1591 | ||
1592 | /* parameters can only be changed when device isn't live */ | |
1593 | mutex_lock(&ub->mutex); | |
1594 | if (ub->dev_info.state == UBLK_S_DEV_LIVE) { | |
1595 | ret = -EACCES; | |
1596 | } else if (copy_from_user(&ub->params, argp, ph.len)) { | |
1597 | ret = -EFAULT; | |
1598 | } else { | |
1599 | /* clear all we don't support yet */ | |
1600 | ub->params.types &= UBLK_PARAM_TYPE_ALL; | |
1601 | ret = ublk_validate_params(ub); | |
1602 | } | |
1603 | mutex_unlock(&ub->mutex); | |
1604 | ublk_put_device(ub); | |
1605 | ||
1606 | return ret; | |
1607 | } | |
1608 | ||
34d8f2be CH |
1609 | static int ublk_ctrl_uring_cmd(struct io_uring_cmd *cmd, |
1610 | unsigned int issue_flags) | |
1611 | { | |
1612 | struct ublksrv_ctrl_cmd *header = (struct ublksrv_ctrl_cmd *)cmd->cmd; | |
71f28f31 ML |
1613 | int ret = -EINVAL; |
1614 | ||
1615 | ublk_ctrl_cmd_dump(cmd); | |
1616 | ||
1617 | if (!(issue_flags & IO_URING_F_SQE128)) | |
1618 | goto out; | |
1619 | ||
34d8f2be CH |
1620 | ret = -EPERM; |
1621 | if (!capable(CAP_SYS_ADMIN)) | |
71f28f31 ML |
1622 | goto out; |
1623 | ||
1624 | ret = -ENODEV; | |
34d8f2be | 1625 | switch (cmd->cmd_op) { |
71f28f31 | 1626 | case UBLK_CMD_START_DEV: |
34d8f2be | 1627 | ret = ublk_ctrl_start_dev(cmd); |
71f28f31 ML |
1628 | break; |
1629 | case UBLK_CMD_STOP_DEV: | |
34d8f2be | 1630 | ret = ublk_ctrl_stop_dev(cmd); |
71f28f31 ML |
1631 | break; |
1632 | case UBLK_CMD_GET_DEV_INFO: | |
34d8f2be | 1633 | ret = ublk_ctrl_get_dev_info(cmd); |
71f28f31 ML |
1634 | break; |
1635 | case UBLK_CMD_ADD_DEV: | |
34d8f2be | 1636 | ret = ublk_ctrl_add_dev(cmd); |
71f28f31 ML |
1637 | break; |
1638 | case UBLK_CMD_DEL_DEV: | |
1639 | ret = ublk_ctrl_del_dev(header->dev_id); | |
1640 | break; | |
1641 | case UBLK_CMD_GET_QUEUE_AFFINITY: | |
1642 | ret = ublk_ctrl_get_queue_affinity(cmd); | |
1643 | break; | |
0aa73170 ML |
1644 | case UBLK_CMD_GET_PARAMS: |
1645 | ret = ublk_ctrl_get_params(cmd); | |
1646 | break; | |
1647 | case UBLK_CMD_SET_PARAMS: | |
1648 | ret = ublk_ctrl_set_params(cmd); | |
1649 | break; | |
71f28f31 ML |
1650 | default: |
1651 | break; | |
6b1439d2 | 1652 | } |
71f28f31 ML |
1653 | out: |
1654 | io_uring_cmd_done(cmd, ret, 0); | |
1655 | pr_devel("%s: cmd done ret %d cmd_op %x, dev id %d qid %d\n", | |
1656 | __func__, ret, cmd->cmd_op, header->dev_id, header->queue_id); | |
1657 | return -EIOCBQUEUED; | |
1658 | } | |
1659 | ||
1660 | static const struct file_operations ublk_ctl_fops = { | |
1661 | .open = nonseekable_open, | |
1662 | .uring_cmd = ublk_ctrl_uring_cmd, | |
1663 | .owner = THIS_MODULE, | |
1664 | .llseek = noop_llseek, | |
1665 | }; | |
1666 | ||
1667 | static struct miscdevice ublk_misc = { | |
1668 | .minor = MISC_DYNAMIC_MINOR, | |
1669 | .name = "ublk-control", | |
1670 | .fops = &ublk_ctl_fops, | |
1671 | }; | |
1672 | ||
1673 | static int __init ublk_init(void) | |
1674 | { | |
1675 | int ret; | |
1676 | ||
1677 | init_waitqueue_head(&ublk_idr_wq); | |
1678 | ||
1679 | ret = misc_register(&ublk_misc); | |
1680 | if (ret) | |
1681 | return ret; | |
1682 | ||
1683 | ret = alloc_chrdev_region(&ublk_chr_devt, 0, UBLK_MINORS, "ublk-char"); | |
1684 | if (ret) | |
1685 | goto unregister_mis; | |
1686 | ||
1687 | ublk_chr_class = class_create(THIS_MODULE, "ublk-char"); | |
1688 | if (IS_ERR(ublk_chr_class)) { | |
1689 | ret = PTR_ERR(ublk_chr_class); | |
1690 | goto free_chrdev_region; | |
1691 | } | |
1692 | return 0; | |
1693 | ||
1694 | free_chrdev_region: | |
1695 | unregister_chrdev_region(ublk_chr_devt, UBLK_MINORS); | |
1696 | unregister_mis: | |
1697 | misc_deregister(&ublk_misc); | |
1698 | return ret; | |
1699 | } | |
1700 | ||
1701 | static void __exit ublk_exit(void) | |
1702 | { | |
1703 | struct ublk_device *ub; | |
1704 | int id; | |
1705 | ||
1706 | class_destroy(ublk_chr_class); | |
1707 | ||
1708 | misc_deregister(&ublk_misc); | |
1709 | ||
1710 | idr_for_each_entry(&ublk_index_idr, ub, id) | |
1711 | ublk_remove(ub); | |
1712 | ||
1713 | idr_destroy(&ublk_index_idr); | |
1714 | unregister_chrdev_region(ublk_chr_devt, UBLK_MINORS); | |
1715 | } | |
1716 | ||
1717 | module_init(ublk_init); | |
1718 | module_exit(ublk_exit); | |
1719 | ||
1720 | MODULE_AUTHOR("Ming Lei <ming.lei@redhat.com>"); | |
1721 | MODULE_LICENSE("GPL"); |