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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> |
4093cb5a | 45 | #include <linux/namei.h> |
82840669 | 46 | #include <linux/kref.h> |
71f28f31 ML |
47 | #include <uapi/linux/ublk_cmd.h> |
48 | ||
49 | #define UBLK_MINORS (1U << MINORBITS) | |
50 | ||
6d8c5afc | 51 | /* All UBLK_F_* have to be included into UBLK_F_ALL */ |
c86019ff Z |
52 | #define UBLK_F_ALL (UBLK_F_SUPPORT_ZERO_COPY \ |
53 | | UBLK_F_URING_CMD_COMP_IN_TASK \ | |
77a440e2 | 54 | | UBLK_F_NEED_GET_DATA \ |
a0d41dc1 | 55 | | UBLK_F_USER_RECOVERY \ |
4093cb5a | 56 | | UBLK_F_USER_RECOVERY_REISSUE \ |
2d786e66 | 57 | | UBLK_F_UNPRIVILEGED_DEV \ |
1172d5b8 ML |
58 | | UBLK_F_CMD_IOCTL_ENCODE \ |
59 | | UBLK_F_USER_COPY) | |
6d8c5afc | 60 | |
0aa73170 | 61 | /* All UBLK_PARAM_TYPE_* should be included here */ |
abb864d3 ML |
62 | #define UBLK_PARAM_TYPE_ALL (UBLK_PARAM_TYPE_BASIC | \ |
63 | UBLK_PARAM_TYPE_DISCARD | UBLK_PARAM_TYPE_DEVT) | |
0aa73170 | 64 | |
0edb3696 | 65 | struct ublk_rq_data { |
7d4a9317 | 66 | struct llist_node node; |
82840669 ML |
67 | |
68 | struct kref ref; | |
0edb3696 ML |
69 | }; |
70 | ||
71f28f31 | 71 | struct ublk_uring_cmd_pdu { |
3ab6e94c | 72 | struct ublk_queue *ubq; |
71f28f31 ML |
73 | }; |
74 | ||
75 | /* | |
76 | * io command is active: sqe cmd is received, and its cqe isn't done | |
77 | * | |
78 | * If the flag is set, the io command is owned by ublk driver, and waited | |
79 | * for incoming blk-mq request from the ublk block device. | |
80 | * | |
81 | * If the flag is cleared, the io command will be completed, and owned by | |
82 | * ublk server. | |
83 | */ | |
84 | #define UBLK_IO_FLAG_ACTIVE 0x01 | |
85 | ||
86 | /* | |
87 | * IO command is completed via cqe, and it is being handled by ublksrv, and | |
88 | * not committed yet | |
89 | * | |
90 | * Basically exclusively with UBLK_IO_FLAG_ACTIVE, so can be served for | |
91 | * cross verification | |
92 | */ | |
93 | #define UBLK_IO_FLAG_OWNED_BY_SRV 0x02 | |
94 | ||
95 | /* | |
96 | * IO command is aborted, so this flag is set in case of | |
97 | * !UBLK_IO_FLAG_ACTIVE. | |
98 | * | |
99 | * After this flag is observed, any pending or new incoming request | |
100 | * associated with this io command will be failed immediately | |
101 | */ | |
102 | #define UBLK_IO_FLAG_ABORTED 0x04 | |
103 | ||
c86019ff Z |
104 | /* |
105 | * UBLK_IO_FLAG_NEED_GET_DATA is set because IO command requires | |
106 | * get data buffer address from ublksrv. | |
107 | * | |
108 | * Then, bio data could be copied into this data buffer for a WRITE request | |
109 | * after the IO command is issued again and UBLK_IO_FLAG_NEED_GET_DATA is unset. | |
110 | */ | |
111 | #define UBLK_IO_FLAG_NEED_GET_DATA 0x08 | |
112 | ||
71f28f31 ML |
113 | struct ublk_io { |
114 | /* userspace buffer address from io cmd */ | |
115 | __u64 addr; | |
116 | unsigned int flags; | |
117 | int res; | |
118 | ||
119 | struct io_uring_cmd *cmd; | |
120 | }; | |
121 | ||
122 | struct ublk_queue { | |
123 | int q_id; | |
124 | int q_depth; | |
125 | ||
0edb3696 | 126 | unsigned long flags; |
71f28f31 ML |
127 | struct task_struct *ubq_daemon; |
128 | char *io_cmd_buf; | |
129 | ||
3ab6e94c ML |
130 | struct llist_head io_cmds; |
131 | ||
71f28f31 ML |
132 | unsigned long io_addr; /* mapped vm address */ |
133 | unsigned int max_io_sz; | |
bbae8d1f | 134 | bool force_abort; |
c0b79b0f | 135 | bool timeout; |
71f28f31 ML |
136 | unsigned short nr_io_ready; /* how many ios setup */ |
137 | struct ublk_device *dev; | |
72495b5a | 138 | struct ublk_io ios[]; |
71f28f31 ML |
139 | }; |
140 | ||
141 | #define UBLK_DAEMON_MONITOR_PERIOD (5 * HZ) | |
142 | ||
143 | struct ublk_device { | |
144 | struct gendisk *ub_disk; | |
71f28f31 ML |
145 | |
146 | char *__queues; | |
147 | ||
29baef78 | 148 | unsigned int queue_size; |
71f28f31 ML |
149 | struct ublksrv_ctrl_dev_info dev_info; |
150 | ||
151 | struct blk_mq_tag_set tag_set; | |
152 | ||
153 | struct cdev cdev; | |
154 | struct device cdev_dev; | |
155 | ||
8d9fdb60 DC |
156 | #define UB_STATE_OPEN 0 |
157 | #define UB_STATE_USED 1 | |
0abe39de | 158 | #define UB_STATE_DELETED 2 |
fa362045 | 159 | unsigned long state; |
71f28f31 ML |
160 | int ub_number; |
161 | ||
162 | struct mutex mutex; | |
163 | ||
e94eb459 | 164 | spinlock_t mm_lock; |
71f28f31 ML |
165 | struct mm_struct *mm; |
166 | ||
0aa73170 ML |
167 | struct ublk_params params; |
168 | ||
71f28f31 ML |
169 | struct completion completion; |
170 | unsigned int nr_queues_ready; | |
73a166d9 | 171 | unsigned int nr_privileged_daemon; |
71f28f31 ML |
172 | |
173 | /* | |
174 | * Our ubq->daemon may be killed without any notification, so | |
175 | * monitor each queue's daemon periodically | |
176 | */ | |
177 | struct delayed_work monitor_work; | |
bbae8d1f | 178 | struct work_struct quiesce_work; |
71f28f31 ML |
179 | struct work_struct stop_work; |
180 | }; | |
181 | ||
0aa73170 ML |
182 | /* header of ublk_params */ |
183 | struct ublk_params_header { | |
184 | __u32 len; | |
185 | __u32 types; | |
186 | }; | |
187 | ||
82840669 ML |
188 | static inline void __ublk_complete_rq(struct request *req); |
189 | static void ublk_complete_rq(struct kref *ref); | |
190 | ||
71f28f31 | 191 | static dev_t ublk_chr_devt; |
2eefd399 IO |
192 | static const struct class ublk_chr_class = { |
193 | .name = "ublk-char", | |
194 | }; | |
71f28f31 ML |
195 | |
196 | static DEFINE_IDR(ublk_index_idr); | |
197 | static DEFINE_SPINLOCK(ublk_idr_lock); | |
198 | static wait_queue_head_t ublk_idr_wq; /* wait until one idr is freed */ | |
199 | ||
200 | static DEFINE_MUTEX(ublk_ctl_mutex); | |
201 | ||
403ebc87 ML |
202 | /* |
203 | * Max ublk devices allowed to add | |
204 | * | |
205 | * It can be extended to one per-user limit in future or even controlled | |
206 | * by cgroup. | |
207 | */ | |
208 | static unsigned int ublks_max = 64; | |
209 | static unsigned int ublks_added; /* protected by ublk_ctl_mutex */ | |
210 | ||
71f28f31 ML |
211 | static struct miscdevice ublk_misc; |
212 | ||
62fe99ce ML |
213 | static inline unsigned ublk_pos_to_hwq(loff_t pos) |
214 | { | |
215 | return ((pos - UBLKSRV_IO_BUF_OFFSET) >> UBLK_QID_OFF) & | |
216 | UBLK_QID_BITS_MASK; | |
217 | } | |
218 | ||
219 | static inline unsigned ublk_pos_to_buf_off(loff_t pos) | |
220 | { | |
221 | return (pos - UBLKSRV_IO_BUF_OFFSET) & UBLK_IO_BUF_BITS_MASK; | |
222 | } | |
223 | ||
224 | static inline unsigned ublk_pos_to_tag(loff_t pos) | |
225 | { | |
226 | return ((pos - UBLKSRV_IO_BUF_OFFSET) >> UBLK_TAG_OFF) & | |
227 | UBLK_TAG_BITS_MASK; | |
228 | } | |
229 | ||
0aa73170 ML |
230 | static void ublk_dev_param_basic_apply(struct ublk_device *ub) |
231 | { | |
232 | struct request_queue *q = ub->ub_disk->queue; | |
233 | const struct ublk_param_basic *p = &ub->params.basic; | |
234 | ||
235 | blk_queue_logical_block_size(q, 1 << p->logical_bs_shift); | |
236 | blk_queue_physical_block_size(q, 1 << p->physical_bs_shift); | |
237 | blk_queue_io_min(q, 1 << p->io_min_shift); | |
238 | blk_queue_io_opt(q, 1 << p->io_opt_shift); | |
239 | ||
240 | blk_queue_write_cache(q, p->attrs & UBLK_ATTR_VOLATILE_CACHE, | |
241 | p->attrs & UBLK_ATTR_FUA); | |
242 | if (p->attrs & UBLK_ATTR_ROTATIONAL) | |
243 | blk_queue_flag_clear(QUEUE_FLAG_NONROT, q); | |
244 | else | |
245 | blk_queue_flag_set(QUEUE_FLAG_NONROT, q); | |
246 | ||
247 | blk_queue_max_hw_sectors(q, p->max_sectors); | |
248 | blk_queue_chunk_sectors(q, p->chunk_sectors); | |
249 | blk_queue_virt_boundary(q, p->virt_boundary_mask); | |
250 | ||
251 | if (p->attrs & UBLK_ATTR_READ_ONLY) | |
252 | set_disk_ro(ub->ub_disk, true); | |
253 | ||
254 | set_capacity(ub->ub_disk, p->dev_sectors); | |
255 | } | |
256 | ||
257 | static void ublk_dev_param_discard_apply(struct ublk_device *ub) | |
258 | { | |
259 | struct request_queue *q = ub->ub_disk->queue; | |
260 | const struct ublk_param_discard *p = &ub->params.discard; | |
261 | ||
262 | q->limits.discard_alignment = p->discard_alignment; | |
263 | q->limits.discard_granularity = p->discard_granularity; | |
264 | blk_queue_max_discard_sectors(q, p->max_discard_sectors); | |
265 | blk_queue_max_write_zeroes_sectors(q, | |
266 | p->max_write_zeroes_sectors); | |
267 | blk_queue_max_discard_segments(q, p->max_discard_segments); | |
268 | } | |
269 | ||
270 | static int ublk_validate_params(const struct ublk_device *ub) | |
271 | { | |
272 | /* basic param is the only one which must be set */ | |
273 | if (ub->params.types & UBLK_PARAM_TYPE_BASIC) { | |
274 | const struct ublk_param_basic *p = &ub->params.basic; | |
275 | ||
1d166527 | 276 | if (p->logical_bs_shift > PAGE_SHIFT || p->logical_bs_shift < 9) |
0aa73170 ML |
277 | return -EINVAL; |
278 | ||
279 | if (p->logical_bs_shift > p->physical_bs_shift) | |
280 | return -EINVAL; | |
281 | ||
4bf9cbf3 | 282 | if (p->max_sectors > (ub->dev_info.max_io_buf_bytes >> 9)) |
0aa73170 ML |
283 | return -EINVAL; |
284 | } else | |
285 | return -EINVAL; | |
286 | ||
287 | if (ub->params.types & UBLK_PARAM_TYPE_DISCARD) { | |
288 | const struct ublk_param_discard *p = &ub->params.discard; | |
289 | ||
290 | /* So far, only support single segment discard */ | |
291 | if (p->max_discard_sectors && p->max_discard_segments != 1) | |
292 | return -EINVAL; | |
293 | ||
294 | if (!p->discard_granularity) | |
295 | return -EINVAL; | |
296 | } | |
297 | ||
abb864d3 ML |
298 | /* dev_t is read-only */ |
299 | if (ub->params.types & UBLK_PARAM_TYPE_DEVT) | |
300 | return -EINVAL; | |
301 | ||
0aa73170 ML |
302 | return 0; |
303 | } | |
304 | ||
305 | static int ublk_apply_params(struct ublk_device *ub) | |
306 | { | |
307 | if (!(ub->params.types & UBLK_PARAM_TYPE_BASIC)) | |
308 | return -EINVAL; | |
309 | ||
310 | ublk_dev_param_basic_apply(ub); | |
311 | ||
312 | if (ub->params.types & UBLK_PARAM_TYPE_DISCARD) | |
313 | ublk_dev_param_discard_apply(ub); | |
314 | ||
315 | return 0; | |
316 | } | |
317 | ||
1172d5b8 | 318 | static inline bool ublk_support_user_copy(const struct ublk_queue *ubq) |
0edb3696 | 319 | { |
1172d5b8 ML |
320 | return ubq->flags & UBLK_F_USER_COPY; |
321 | } | |
322 | ||
82840669 ML |
323 | static inline bool ublk_need_req_ref(const struct ublk_queue *ubq) |
324 | { | |
1172d5b8 ML |
325 | /* |
326 | * read()/write() is involved in user copy, so request reference | |
327 | * has to be grabbed | |
328 | */ | |
329 | return ublk_support_user_copy(ubq); | |
82840669 ML |
330 | } |
331 | ||
332 | static inline void ublk_init_req_ref(const struct ublk_queue *ubq, | |
333 | struct request *req) | |
334 | { | |
335 | if (ublk_need_req_ref(ubq)) { | |
336 | struct ublk_rq_data *data = blk_mq_rq_to_pdu(req); | |
337 | ||
338 | kref_init(&data->ref); | |
339 | } | |
340 | } | |
341 | ||
342 | static inline bool ublk_get_req_ref(const struct ublk_queue *ubq, | |
343 | struct request *req) | |
344 | { | |
345 | if (ublk_need_req_ref(ubq)) { | |
346 | struct ublk_rq_data *data = blk_mq_rq_to_pdu(req); | |
347 | ||
348 | return kref_get_unless_zero(&data->ref); | |
349 | } | |
350 | ||
351 | return true; | |
352 | } | |
353 | ||
354 | static inline void ublk_put_req_ref(const struct ublk_queue *ubq, | |
355 | struct request *req) | |
356 | { | |
357 | if (ublk_need_req_ref(ubq)) { | |
358 | struct ublk_rq_data *data = blk_mq_rq_to_pdu(req); | |
359 | ||
360 | kref_put(&data->ref, ublk_complete_rq); | |
361 | } else { | |
362 | __ublk_complete_rq(req); | |
363 | } | |
0edb3696 ML |
364 | } |
365 | ||
c86019ff Z |
366 | static inline bool ublk_need_get_data(const struct ublk_queue *ubq) |
367 | { | |
96cf2f54 | 368 | return ubq->flags & UBLK_F_NEED_GET_DATA; |
c86019ff Z |
369 | } |
370 | ||
71f28f31 ML |
371 | static struct ublk_device *ublk_get_device(struct ublk_device *ub) |
372 | { | |
373 | if (kobject_get_unless_zero(&ub->cdev_dev.kobj)) | |
374 | return ub; | |
375 | return NULL; | |
376 | } | |
377 | ||
378 | static void ublk_put_device(struct ublk_device *ub) | |
379 | { | |
380 | put_device(&ub->cdev_dev); | |
381 | } | |
382 | ||
383 | static inline struct ublk_queue *ublk_get_queue(struct ublk_device *dev, | |
384 | int qid) | |
385 | { | |
386 | return (struct ublk_queue *)&(dev->__queues[qid * dev->queue_size]); | |
387 | } | |
388 | ||
389 | static inline bool ublk_rq_has_data(const struct request *rq) | |
390 | { | |
731e208d | 391 | return bio_has_data(rq->bio); |
71f28f31 ML |
392 | } |
393 | ||
394 | static inline struct ublksrv_io_desc *ublk_get_iod(struct ublk_queue *ubq, | |
395 | int tag) | |
396 | { | |
397 | return (struct ublksrv_io_desc *) | |
398 | &(ubq->io_cmd_buf[tag * sizeof(struct ublksrv_io_desc)]); | |
399 | } | |
400 | ||
401 | static inline char *ublk_queue_cmd_buf(struct ublk_device *ub, int q_id) | |
402 | { | |
403 | return ublk_get_queue(ub, q_id)->io_cmd_buf; | |
404 | } | |
405 | ||
406 | static inline int ublk_queue_cmd_buf_size(struct ublk_device *ub, int q_id) | |
407 | { | |
408 | struct ublk_queue *ubq = ublk_get_queue(ub, q_id); | |
409 | ||
410 | return round_up(ubq->q_depth * sizeof(struct ublksrv_io_desc), | |
411 | PAGE_SIZE); | |
412 | } | |
413 | ||
a0d41dc1 Z |
414 | static inline bool ublk_queue_can_use_recovery_reissue( |
415 | struct ublk_queue *ubq) | |
416 | { | |
96cf2f54 ML |
417 | return (ubq->flags & UBLK_F_USER_RECOVERY) && |
418 | (ubq->flags & UBLK_F_USER_RECOVERY_REISSUE); | |
a0d41dc1 Z |
419 | } |
420 | ||
77a440e2 Z |
421 | static inline bool ublk_queue_can_use_recovery( |
422 | struct ublk_queue *ubq) | |
423 | { | |
96cf2f54 | 424 | return ubq->flags & UBLK_F_USER_RECOVERY; |
77a440e2 Z |
425 | } |
426 | ||
427 | static inline bool ublk_can_use_recovery(struct ublk_device *ub) | |
428 | { | |
96cf2f54 | 429 | return ub->dev_info.flags & UBLK_F_USER_RECOVERY; |
77a440e2 Z |
430 | } |
431 | ||
6d9e6dfd CH |
432 | static void ublk_free_disk(struct gendisk *disk) |
433 | { | |
434 | struct ublk_device *ub = disk->private_data; | |
435 | ||
436 | clear_bit(UB_STATE_USED, &ub->state); | |
437 | put_device(&ub->cdev_dev); | |
438 | } | |
439 | ||
48a90519 ML |
440 | static void ublk_store_owner_uid_gid(unsigned int *owner_uid, |
441 | unsigned int *owner_gid) | |
442 | { | |
443 | kuid_t uid; | |
444 | kgid_t gid; | |
445 | ||
446 | current_uid_gid(&uid, &gid); | |
447 | ||
448 | *owner_uid = from_kuid(&init_user_ns, uid); | |
449 | *owner_gid = from_kgid(&init_user_ns, gid); | |
450 | } | |
451 | ||
05bdb996 | 452 | static int ublk_open(struct gendisk *disk, blk_mode_t mode) |
48a90519 | 453 | { |
d32e2bf8 | 454 | struct ublk_device *ub = disk->private_data; |
48a90519 ML |
455 | |
456 | if (capable(CAP_SYS_ADMIN)) | |
457 | return 0; | |
458 | ||
459 | /* | |
460 | * If it is one unprivileged device, only owner can open | |
461 | * the disk. Otherwise it could be one trap made by one | |
462 | * evil user who grants this disk's privileges to other | |
463 | * users deliberately. | |
464 | * | |
465 | * This way is reasonable too given anyone can create | |
466 | * unprivileged device, and no need other's grant. | |
467 | */ | |
468 | if (ub->dev_info.flags & UBLK_F_UNPRIVILEGED_DEV) { | |
469 | unsigned int curr_uid, curr_gid; | |
470 | ||
471 | ublk_store_owner_uid_gid(&curr_uid, &curr_gid); | |
472 | ||
473 | if (curr_uid != ub->dev_info.owner_uid || curr_gid != | |
474 | ub->dev_info.owner_gid) | |
475 | return -EPERM; | |
476 | } | |
477 | ||
478 | return 0; | |
479 | } | |
480 | ||
71f28f31 ML |
481 | static const struct block_device_operations ub_fops = { |
482 | .owner = THIS_MODULE, | |
48a90519 | 483 | .open = ublk_open, |
6d9e6dfd | 484 | .free_disk = ublk_free_disk, |
71f28f31 ML |
485 | }; |
486 | ||
487 | #define UBLK_MAX_PIN_PAGES 32 | |
488 | ||
71f28f31 ML |
489 | struct ublk_io_iter { |
490 | struct page *pages[UBLK_MAX_PIN_PAGES]; | |
71f28f31 ML |
491 | struct bio *bio; |
492 | struct bvec_iter iter; | |
493 | }; | |
494 | ||
981f95a5 ML |
495 | /* return how many pages are copied */ |
496 | static void ublk_copy_io_pages(struct ublk_io_iter *data, | |
497 | size_t total, size_t pg_off, int dir) | |
71f28f31 | 498 | { |
71f28f31 ML |
499 | unsigned done = 0; |
500 | unsigned pg_idx = 0; | |
501 | ||
502 | while (done < total) { | |
503 | struct bio_vec bv = bio_iter_iovec(data->bio, data->iter); | |
981f95a5 ML |
504 | unsigned int bytes = min3(bv.bv_len, (unsigned)total - done, |
505 | (unsigned)(PAGE_SIZE - pg_off)); | |
71f28f31 ML |
506 | void *bv_buf = bvec_kmap_local(&bv); |
507 | void *pg_buf = kmap_local_page(data->pages[pg_idx]); | |
508 | ||
981f95a5 ML |
509 | if (dir == ITER_DEST) |
510 | memcpy(pg_buf + pg_off, bv_buf, bytes); | |
71f28f31 | 511 | else |
981f95a5 | 512 | memcpy(bv_buf, pg_buf + pg_off, bytes); |
71f28f31 ML |
513 | |
514 | kunmap_local(pg_buf); | |
515 | kunmap_local(bv_buf); | |
516 | ||
517 | /* advance page array */ | |
981f95a5 ML |
518 | pg_off += bytes; |
519 | if (pg_off == PAGE_SIZE) { | |
71f28f31 | 520 | pg_idx += 1; |
981f95a5 | 521 | pg_off = 0; |
71f28f31 ML |
522 | } |
523 | ||
524 | done += bytes; | |
525 | ||
526 | /* advance bio */ | |
527 | bio_advance_iter_single(data->bio, &data->iter, bytes); | |
528 | if (!data->iter.bi_size) { | |
529 | data->bio = data->bio->bi_next; | |
530 | if (data->bio == NULL) | |
531 | break; | |
532 | data->iter = data->bio->bi_iter; | |
533 | } | |
534 | } | |
71f28f31 | 535 | } |
71f28f31 | 536 | |
38f2dd34 ML |
537 | static bool ublk_advance_io_iter(const struct request *req, |
538 | struct ublk_io_iter *iter, unsigned int offset) | |
539 | { | |
540 | struct bio *bio = req->bio; | |
541 | ||
542 | for_each_bio(bio) { | |
543 | if (bio->bi_iter.bi_size > offset) { | |
544 | iter->bio = bio; | |
545 | iter->iter = bio->bi_iter; | |
546 | bio_advance_iter(iter->bio, &iter->iter, offset); | |
547 | return true; | |
548 | } | |
549 | offset -= bio->bi_iter.bi_size; | |
550 | } | |
551 | return false; | |
71f28f31 ML |
552 | } |
553 | ||
981f95a5 ML |
554 | /* |
555 | * Copy data between request pages and io_iter, and 'offset' | |
556 | * is the start point of linear offset of request. | |
557 | */ | |
558 | static size_t ublk_copy_user_pages(const struct request *req, | |
38f2dd34 | 559 | unsigned offset, struct iov_iter *uiter, int dir) |
71f28f31 | 560 | { |
38f2dd34 | 561 | struct ublk_io_iter iter; |
981f95a5 ML |
562 | size_t done = 0; |
563 | ||
38f2dd34 ML |
564 | if (!ublk_advance_io_iter(req, &iter, offset)) |
565 | return 0; | |
566 | ||
981f95a5 ML |
567 | while (iov_iter_count(uiter) && iter.bio) { |
568 | unsigned nr_pages; | |
b8b637d7 ML |
569 | ssize_t len; |
570 | size_t off; | |
981f95a5 ML |
571 | int i; |
572 | ||
573 | len = iov_iter_get_pages2(uiter, iter.pages, | |
574 | iov_iter_count(uiter), | |
575 | UBLK_MAX_PIN_PAGES, &off); | |
576 | if (len <= 0) | |
577 | return done; | |
578 | ||
579 | ublk_copy_io_pages(&iter, len, off, dir); | |
580 | nr_pages = DIV_ROUND_UP(len + off, PAGE_SIZE); | |
581 | for (i = 0; i < nr_pages; i++) { | |
582 | if (dir == ITER_DEST) | |
71f28f31 ML |
583 | set_page_dirty(iter.pages[i]); |
584 | put_page(iter.pages[i]); | |
585 | } | |
981f95a5 | 586 | done += len; |
71f28f31 ML |
587 | } |
588 | ||
589 | return done; | |
590 | } | |
591 | ||
2f3af723 ML |
592 | static inline bool ublk_need_map_req(const struct request *req) |
593 | { | |
594 | return ublk_rq_has_data(req) && req_op(req) == REQ_OP_WRITE; | |
595 | } | |
596 | ||
597 | static inline bool ublk_need_unmap_req(const struct request *req) | |
598 | { | |
599 | return ublk_rq_has_data(req) && req_op(req) == REQ_OP_READ; | |
600 | } | |
601 | ||
71f28f31 ML |
602 | static int ublk_map_io(const struct ublk_queue *ubq, const struct request *req, |
603 | struct ublk_io *io) | |
604 | { | |
605 | const unsigned int rq_bytes = blk_rq_bytes(req); | |
23ef8220 | 606 | |
1172d5b8 ML |
607 | if (ublk_support_user_copy(ubq)) |
608 | return rq_bytes; | |
609 | ||
71f28f31 ML |
610 | /* |
611 | * no zero copy, we delay copy WRITE request data into ublksrv | |
612 | * context and the big benefit is that pinning pages in current | |
613 | * context is pretty fast, see ublk_pin_user_pages | |
614 | */ | |
2f3af723 | 615 | if (ublk_need_map_req(req)) { |
981f95a5 ML |
616 | struct iov_iter iter; |
617 | struct iovec iov; | |
618 | const int dir = ITER_DEST; | |
71f28f31 | 619 | |
981f95a5 ML |
620 | import_single_range(dir, u64_to_user_ptr(io->addr), rq_bytes, |
621 | &iov, &iter); | |
71f28f31 | 622 | |
38f2dd34 | 623 | return ublk_copy_user_pages(req, 0, &iter, dir); |
71f28f31 ML |
624 | } |
625 | return rq_bytes; | |
626 | } | |
627 | ||
628 | static int ublk_unmap_io(const struct ublk_queue *ubq, | |
629 | const struct request *req, | |
630 | struct ublk_io *io) | |
631 | { | |
632 | const unsigned int rq_bytes = blk_rq_bytes(req); | |
633 | ||
1172d5b8 ML |
634 | if (ublk_support_user_copy(ubq)) |
635 | return rq_bytes; | |
636 | ||
2f3af723 | 637 | if (ublk_need_unmap_req(req)) { |
981f95a5 ML |
638 | struct iov_iter iter; |
639 | struct iovec iov; | |
640 | const int dir = ITER_SOURCE; | |
71f28f31 ML |
641 | |
642 | WARN_ON_ONCE(io->res > rq_bytes); | |
643 | ||
981f95a5 ML |
644 | import_single_range(dir, u64_to_user_ptr(io->addr), io->res, |
645 | &iov, &iter); | |
38f2dd34 | 646 | return ublk_copy_user_pages(req, 0, &iter, dir); |
71f28f31 ML |
647 | } |
648 | return rq_bytes; | |
649 | } | |
650 | ||
651 | static inline unsigned int ublk_req_build_flags(struct request *req) | |
652 | { | |
653 | unsigned flags = 0; | |
654 | ||
655 | if (req->cmd_flags & REQ_FAILFAST_DEV) | |
656 | flags |= UBLK_IO_F_FAILFAST_DEV; | |
657 | ||
658 | if (req->cmd_flags & REQ_FAILFAST_TRANSPORT) | |
659 | flags |= UBLK_IO_F_FAILFAST_TRANSPORT; | |
660 | ||
661 | if (req->cmd_flags & REQ_FAILFAST_DRIVER) | |
662 | flags |= UBLK_IO_F_FAILFAST_DRIVER; | |
663 | ||
664 | if (req->cmd_flags & REQ_META) | |
665 | flags |= UBLK_IO_F_META; | |
666 | ||
71f28f31 ML |
667 | if (req->cmd_flags & REQ_FUA) |
668 | flags |= UBLK_IO_F_FUA; | |
669 | ||
71f28f31 ML |
670 | if (req->cmd_flags & REQ_NOUNMAP) |
671 | flags |= UBLK_IO_F_NOUNMAP; | |
672 | ||
673 | if (req->cmd_flags & REQ_SWAP) | |
674 | flags |= UBLK_IO_F_SWAP; | |
675 | ||
676 | return flags; | |
677 | } | |
678 | ||
f2450f8a | 679 | static blk_status_t ublk_setup_iod(struct ublk_queue *ubq, struct request *req) |
71f28f31 ML |
680 | { |
681 | struct ublksrv_io_desc *iod = ublk_get_iod(ubq, req->tag); | |
682 | struct ublk_io *io = &ubq->ios[req->tag]; | |
683 | u32 ublk_op; | |
684 | ||
685 | switch (req_op(req)) { | |
686 | case REQ_OP_READ: | |
687 | ublk_op = UBLK_IO_OP_READ; | |
688 | break; | |
689 | case REQ_OP_WRITE: | |
690 | ublk_op = UBLK_IO_OP_WRITE; | |
691 | break; | |
692 | case REQ_OP_FLUSH: | |
693 | ublk_op = UBLK_IO_OP_FLUSH; | |
694 | break; | |
695 | case REQ_OP_DISCARD: | |
696 | ublk_op = UBLK_IO_OP_DISCARD; | |
697 | break; | |
698 | case REQ_OP_WRITE_ZEROES: | |
699 | ublk_op = UBLK_IO_OP_WRITE_ZEROES; | |
700 | break; | |
701 | default: | |
702 | return BLK_STS_IOERR; | |
703 | } | |
704 | ||
705 | /* need to translate since kernel may change */ | |
706 | iod->op_flags = ublk_op | ublk_req_build_flags(req); | |
707 | iod->nr_sectors = blk_rq_sectors(req); | |
708 | iod->start_sector = blk_rq_pos(req); | |
709 | iod->addr = io->addr; | |
710 | ||
711 | return BLK_STS_OK; | |
712 | } | |
713 | ||
714 | static inline struct ublk_uring_cmd_pdu *ublk_get_uring_cmd_pdu( | |
715 | struct io_uring_cmd *ioucmd) | |
716 | { | |
717 | return (struct ublk_uring_cmd_pdu *)&ioucmd->pdu; | |
718 | } | |
719 | ||
966120b5 | 720 | static inline bool ubq_daemon_is_dying(struct ublk_queue *ubq) |
71f28f31 ML |
721 | { |
722 | return ubq->ubq_daemon->flags & PF_EXITING; | |
723 | } | |
724 | ||
725 | /* todo: handle partial completion */ | |
82840669 | 726 | static inline void __ublk_complete_rq(struct request *req) |
71f28f31 ML |
727 | { |
728 | struct ublk_queue *ubq = req->mq_hctx->driver_data; | |
729 | struct ublk_io *io = &ubq->ios[req->tag]; | |
730 | unsigned int unmapped_bytes; | |
903f8aee | 731 | blk_status_t res = BLK_STS_OK; |
71f28f31 | 732 | |
82840669 ML |
733 | /* called from ublk_abort_queue() code path */ |
734 | if (io->flags & UBLK_IO_FLAG_ABORTED) { | |
735 | res = BLK_STS_IOERR; | |
736 | goto exit; | |
737 | } | |
738 | ||
71f28f31 ML |
739 | /* failed read IO if nothing is read */ |
740 | if (!io->res && req_op(req) == REQ_OP_READ) | |
741 | io->res = -EIO; | |
742 | ||
743 | if (io->res < 0) { | |
903f8aee ML |
744 | res = errno_to_blk_status(io->res); |
745 | goto exit; | |
71f28f31 ML |
746 | } |
747 | ||
748 | /* | |
b352389e | 749 | * FLUSH, DISCARD or WRITE_ZEROES usually won't return bytes returned, so end them |
71f28f31 ML |
750 | * directly. |
751 | * | |
752 | * Both the two needn't unmap. | |
753 | */ | |
903f8aee ML |
754 | if (req_op(req) != REQ_OP_READ && req_op(req) != REQ_OP_WRITE) |
755 | goto exit; | |
71f28f31 ML |
756 | |
757 | /* for READ request, writing data in iod->addr to rq buffers */ | |
758 | unmapped_bytes = ublk_unmap_io(ubq, req, io); | |
759 | ||
760 | /* | |
761 | * Extremely impossible since we got data filled in just before | |
762 | * | |
763 | * Re-read simply for this unlikely case. | |
764 | */ | |
765 | if (unlikely(unmapped_bytes < io->res)) | |
766 | io->res = unmapped_bytes; | |
767 | ||
768 | if (blk_update_request(req, BLK_STS_OK, io->res)) | |
769 | blk_mq_requeue_request(req, true); | |
770 | else | |
771 | __blk_mq_end_request(req, BLK_STS_OK); | |
903f8aee ML |
772 | |
773 | return; | |
774 | exit: | |
775 | blk_mq_end_request(req, res); | |
71f28f31 ML |
776 | } |
777 | ||
82840669 ML |
778 | static void ublk_complete_rq(struct kref *ref) |
779 | { | |
780 | struct ublk_rq_data *data = container_of(ref, struct ublk_rq_data, | |
781 | ref); | |
782 | struct request *req = blk_mq_rq_from_pdu(data); | |
783 | ||
784 | __ublk_complete_rq(req); | |
785 | } | |
786 | ||
71f28f31 | 787 | /* |
bb241747 Z |
788 | * Since __ublk_rq_task_work always fails requests immediately during |
789 | * exiting, __ublk_fail_req() is only called from abort context during | |
790 | * exiting. So lock is unnecessary. | |
71f28f31 ML |
791 | * |
792 | * Also aborting may not be started yet, keep in mind that one failed | |
793 | * request may be issued by block layer again. | |
794 | */ | |
a0d41dc1 Z |
795 | static void __ublk_fail_req(struct ublk_queue *ubq, struct ublk_io *io, |
796 | struct request *req) | |
71f28f31 ML |
797 | { |
798 | WARN_ON_ONCE(io->flags & UBLK_IO_FLAG_ACTIVE); | |
799 | ||
800 | if (!(io->flags & UBLK_IO_FLAG_ABORTED)) { | |
801 | io->flags |= UBLK_IO_FLAG_ABORTED; | |
a0d41dc1 Z |
802 | if (ublk_queue_can_use_recovery_reissue(ubq)) |
803 | blk_mq_requeue_request(req, false); | |
804 | else | |
82840669 | 805 | ublk_put_req_ref(ubq, req); |
71f28f31 ML |
806 | } |
807 | } | |
808 | ||
9d2789ac JA |
809 | static void ubq_complete_io_cmd(struct ublk_io *io, int res, |
810 | unsigned issue_flags) | |
c86019ff Z |
811 | { |
812 | /* mark this cmd owned by ublksrv */ | |
813 | io->flags |= UBLK_IO_FLAG_OWNED_BY_SRV; | |
814 | ||
815 | /* | |
816 | * clear ACTIVE since we are done with this sqe/cmd slot | |
817 | * We can only accept io cmd in case of being not active. | |
818 | */ | |
819 | io->flags &= ~UBLK_IO_FLAG_ACTIVE; | |
820 | ||
821 | /* tell ublksrv one io request is coming */ | |
9d2789ac | 822 | io_uring_cmd_done(io->cmd, res, 0, issue_flags); |
c86019ff Z |
823 | } |
824 | ||
71f28f31 ML |
825 | #define UBLK_REQUEUE_DELAY_MS 3 |
826 | ||
42cf5fc5 Z |
827 | static inline void __ublk_abort_rq(struct ublk_queue *ubq, |
828 | struct request *rq) | |
829 | { | |
830 | /* We cannot process this rq so just requeue it. */ | |
831 | if (ublk_queue_can_use_recovery(ubq)) | |
832 | blk_mq_requeue_request(rq, false); | |
833 | else | |
834 | blk_mq_end_request(rq, BLK_STS_IOERR); | |
835 | ||
836 | mod_delayed_work(system_wq, &ubq->dev->monitor_work, 0); | |
837 | } | |
838 | ||
9d2789ac JA |
839 | static inline void __ublk_rq_task_work(struct request *req, |
840 | unsigned issue_flags) | |
71f28f31 | 841 | { |
71f28f31 ML |
842 | struct ublk_queue *ubq = req->mq_hctx->driver_data; |
843 | int tag = req->tag; | |
844 | struct ublk_io *io = &ubq->ios[tag]; | |
71f28f31 ML |
845 | unsigned int mapped_bytes; |
846 | ||
847 | pr_devel("%s: complete: op %d, qid %d tag %d io_flags %x addr %llx\n", | |
848 | __func__, io->cmd->cmd_op, ubq->q_id, req->tag, io->flags, | |
849 | ublk_get_iod(ubq, req->tag)->addr); | |
850 | ||
ae3f7193 Z |
851 | /* |
852 | * Task is exiting if either: | |
853 | * | |
854 | * (1) current != ubq_daemon. | |
855 | * io_uring_cmd_complete_in_task() tries to run task_work | |
856 | * in a workqueue if ubq_daemon(cmd's task) is PF_EXITING. | |
857 | * | |
858 | * (2) current->flags & PF_EXITING. | |
859 | */ | |
860 | if (unlikely(current != ubq->ubq_daemon || current->flags & PF_EXITING)) { | |
42cf5fc5 | 861 | __ublk_abort_rq(ubq, req); |
71f28f31 ML |
862 | return; |
863 | } | |
864 | ||
2f3af723 | 865 | if (ublk_need_get_data(ubq) && ublk_need_map_req(req)) { |
c86019ff Z |
866 | /* |
867 | * We have not handled UBLK_IO_NEED_GET_DATA command yet, | |
868 | * so immepdately pass UBLK_IO_RES_NEED_GET_DATA to ublksrv | |
869 | * and notify it. | |
870 | */ | |
871 | if (!(io->flags & UBLK_IO_FLAG_NEED_GET_DATA)) { | |
872 | io->flags |= UBLK_IO_FLAG_NEED_GET_DATA; | |
873 | pr_devel("%s: need get data. op %d, qid %d tag %d io_flags %x\n", | |
874 | __func__, io->cmd->cmd_op, ubq->q_id, | |
875 | req->tag, io->flags); | |
9d2789ac | 876 | ubq_complete_io_cmd(io, UBLK_IO_RES_NEED_GET_DATA, issue_flags); |
c86019ff Z |
877 | return; |
878 | } | |
879 | /* | |
880 | * We have handled UBLK_IO_NEED_GET_DATA command, | |
881 | * so clear UBLK_IO_FLAG_NEED_GET_DATA now and just | |
882 | * do the copy work. | |
883 | */ | |
884 | io->flags &= ~UBLK_IO_FLAG_NEED_GET_DATA; | |
92cb6e2e Z |
885 | /* update iod->addr because ublksrv may have passed a new io buffer */ |
886 | ublk_get_iod(ubq, req->tag)->addr = io->addr; | |
887 | pr_devel("%s: update iod->addr: op %d, qid %d tag %d io_flags %x addr %llx\n", | |
888 | __func__, io->cmd->cmd_op, ubq->q_id, req->tag, io->flags, | |
889 | ublk_get_iod(ubq, req->tag)->addr); | |
c86019ff Z |
890 | } |
891 | ||
71f28f31 ML |
892 | mapped_bytes = ublk_map_io(ubq, req, io); |
893 | ||
894 | /* partially mapped, update io descriptor */ | |
895 | if (unlikely(mapped_bytes != blk_rq_bytes(req))) { | |
896 | /* | |
897 | * Nothing mapped, retry until we succeed. | |
898 | * | |
899 | * We may never succeed in mapping any bytes here because | |
900 | * of OOM. TODO: reserve one buffer with single page pinned | |
901 | * for providing forward progress guarantee. | |
902 | */ | |
903 | if (unlikely(!mapped_bytes)) { | |
904 | blk_mq_requeue_request(req, false); | |
905 | blk_mq_delay_kick_requeue_list(req->q, | |
906 | UBLK_REQUEUE_DELAY_MS); | |
907 | return; | |
908 | } | |
909 | ||
910 | ublk_get_iod(ubq, req->tag)->nr_sectors = | |
911 | mapped_bytes >> 9; | |
912 | } | |
913 | ||
82840669 | 914 | ublk_init_req_ref(ubq, req); |
9d2789ac | 915 | ubq_complete_io_cmd(io, UBLK_IO_RES_OK, issue_flags); |
71f28f31 ML |
916 | } |
917 | ||
9d2789ac JA |
918 | static inline void ublk_forward_io_cmds(struct ublk_queue *ubq, |
919 | unsigned issue_flags) | |
7d4a9317 ML |
920 | { |
921 | struct llist_node *io_cmds = llist_del_all(&ubq->io_cmds); | |
922 | struct ublk_rq_data *data, *tmp; | |
923 | ||
924 | io_cmds = llist_reverse_order(io_cmds); | |
925 | llist_for_each_entry_safe(data, tmp, io_cmds, node) | |
9d2789ac | 926 | __ublk_rq_task_work(blk_mq_rq_from_pdu(data), issue_flags); |
7d4a9317 ML |
927 | } |
928 | ||
929 | static inline void ublk_abort_io_cmds(struct ublk_queue *ubq) | |
930 | { | |
931 | struct llist_node *io_cmds = llist_del_all(&ubq->io_cmds); | |
932 | struct ublk_rq_data *data, *tmp; | |
933 | ||
934 | llist_for_each_entry_safe(data, tmp, io_cmds, node) | |
935 | __ublk_abort_rq(ubq, blk_mq_rq_from_pdu(data)); | |
936 | } | |
937 | ||
9d2789ac | 938 | static void ublk_rq_task_work_cb(struct io_uring_cmd *cmd, unsigned issue_flags) |
0edb3696 ML |
939 | { |
940 | struct ublk_uring_cmd_pdu *pdu = ublk_get_uring_cmd_pdu(cmd); | |
3ab6e94c | 941 | struct ublk_queue *ubq = pdu->ubq; |
0edb3696 | 942 | |
9d2789ac | 943 | ublk_forward_io_cmds(ubq, issue_flags); |
0edb3696 ML |
944 | } |
945 | ||
7d4a9317 | 946 | static void ublk_queue_cmd(struct ublk_queue *ubq, struct request *rq) |
3ab6e94c | 947 | { |
7d4a9317 ML |
948 | struct ublk_rq_data *data = blk_mq_rq_to_pdu(rq); |
949 | struct ublk_io *io; | |
3ab6e94c | 950 | |
7d4a9317 ML |
951 | if (!llist_add(&data->node, &ubq->io_cmds)) |
952 | return; | |
953 | ||
954 | io = &ubq->ios[rq->tag]; | |
3ab6e94c ML |
955 | /* |
956 | * If the check pass, we know that this is a re-issued request aborted | |
957 | * previously in monitor_work because the ubq_daemon(cmd's task) is | |
958 | * PF_EXITING. We cannot call io_uring_cmd_complete_in_task() anymore | |
959 | * because this ioucmd's io_uring context may be freed now if no inflight | |
960 | * ioucmd exists. Otherwise we may cause null-deref in ctx->fallback_work. | |
961 | * | |
962 | * Note: monitor_work sets UBLK_IO_FLAG_ABORTED and ends this request(releasing | |
963 | * the tag). Then the request is re-started(allocating the tag) and we are here. | |
964 | * Since releasing/allocating a tag implies smp_mb(), finding UBLK_IO_FLAG_ABORTED | |
965 | * guarantees that here is a re-issued request aborted previously. | |
966 | */ | |
967 | if (unlikely(io->flags & UBLK_IO_FLAG_ABORTED)) { | |
7d4a9317 | 968 | ublk_abort_io_cmds(ubq); |
3ab6e94c ML |
969 | } else { |
970 | struct io_uring_cmd *cmd = io->cmd; | |
971 | struct ublk_uring_cmd_pdu *pdu = ublk_get_uring_cmd_pdu(cmd); | |
972 | ||
973 | pdu->ubq = ubq; | |
974 | io_uring_cmd_complete_in_task(cmd, ublk_rq_task_work_cb); | |
975 | } | |
976 | } | |
977 | ||
c0b79b0f ML |
978 | static enum blk_eh_timer_return ublk_timeout(struct request *rq) |
979 | { | |
980 | struct ublk_queue *ubq = rq->mq_hctx->driver_data; | |
981 | ||
982 | if (ubq->flags & UBLK_F_UNPRIVILEGED_DEV) { | |
983 | if (!ubq->timeout) { | |
984 | send_sig(SIGKILL, ubq->ubq_daemon, 0); | |
985 | ubq->timeout = true; | |
986 | } | |
987 | ||
988 | return BLK_EH_DONE; | |
989 | } | |
990 | ||
991 | return BLK_EH_RESET_TIMER; | |
992 | } | |
993 | ||
71f28f31 ML |
994 | static blk_status_t ublk_queue_rq(struct blk_mq_hw_ctx *hctx, |
995 | const struct blk_mq_queue_data *bd) | |
996 | { | |
997 | struct ublk_queue *ubq = hctx->driver_data; | |
998 | struct request *rq = bd->rq; | |
71f28f31 ML |
999 | blk_status_t res; |
1000 | ||
1001 | /* fill iod to slot in io cmd buffer */ | |
1002 | res = ublk_setup_iod(ubq, rq); | |
1003 | if (unlikely(res != BLK_STS_OK)) | |
1004 | return BLK_STS_IOERR; | |
3ab6e94c | 1005 | |
bbae8d1f Z |
1006 | /* With recovery feature enabled, force_abort is set in |
1007 | * ublk_stop_dev() before calling del_gendisk(). We have to | |
1008 | * abort all requeued and new rqs here to let del_gendisk() | |
1009 | * move on. Besides, we cannot not call io_uring_cmd_complete_in_task() | |
1010 | * to avoid UAF on io_uring ctx. | |
1011 | * | |
1012 | * Note: force_abort is guaranteed to be seen because it is set | |
1013 | * before request queue is unqiuesced. | |
1014 | */ | |
1015 | if (ublk_queue_can_use_recovery(ubq) && unlikely(ubq->force_abort)) | |
1016 | return BLK_STS_IOERR; | |
71f28f31 ML |
1017 | |
1018 | blk_mq_start_request(bd->rq); | |
1019 | ||
1020 | if (unlikely(ubq_daemon_is_dying(ubq))) { | |
42cf5fc5 Z |
1021 | __ublk_abort_rq(ubq, rq); |
1022 | return BLK_STS_OK; | |
71f28f31 ML |
1023 | } |
1024 | ||
7d4a9317 | 1025 | ublk_queue_cmd(ubq, rq); |
0edb3696 | 1026 | |
71f28f31 ML |
1027 | return BLK_STS_OK; |
1028 | } | |
1029 | ||
71f28f31 ML |
1030 | static int ublk_init_hctx(struct blk_mq_hw_ctx *hctx, void *driver_data, |
1031 | unsigned int hctx_idx) | |
1032 | { | |
cebbe577 | 1033 | struct ublk_device *ub = driver_data; |
71f28f31 ML |
1034 | struct ublk_queue *ubq = ublk_get_queue(ub, hctx->queue_num); |
1035 | ||
1036 | hctx->driver_data = ubq; | |
1037 | return 0; | |
1038 | } | |
1039 | ||
1040 | static const struct blk_mq_ops ublk_mq_ops = { | |
1041 | .queue_rq = ublk_queue_rq, | |
1042 | .init_hctx = ublk_init_hctx, | |
c0b79b0f | 1043 | .timeout = ublk_timeout, |
71f28f31 ML |
1044 | }; |
1045 | ||
1046 | static int ublk_ch_open(struct inode *inode, struct file *filp) | |
1047 | { | |
1048 | struct ublk_device *ub = container_of(inode->i_cdev, | |
1049 | struct ublk_device, cdev); | |
1050 | ||
fa362045 CH |
1051 | if (test_and_set_bit(UB_STATE_OPEN, &ub->state)) |
1052 | return -EBUSY; | |
1053 | filp->private_data = ub; | |
1054 | return 0; | |
71f28f31 ML |
1055 | } |
1056 | ||
1057 | static int ublk_ch_release(struct inode *inode, struct file *filp) | |
1058 | { | |
1059 | struct ublk_device *ub = filp->private_data; | |
1060 | ||
fa362045 | 1061 | clear_bit(UB_STATE_OPEN, &ub->state); |
71f28f31 ML |
1062 | return 0; |
1063 | } | |
1064 | ||
1065 | /* map pre-allocated per-queue cmd buffer to ublksrv daemon */ | |
1066 | static int ublk_ch_mmap(struct file *filp, struct vm_area_struct *vma) | |
1067 | { | |
1068 | struct ublk_device *ub = filp->private_data; | |
1069 | size_t sz = vma->vm_end - vma->vm_start; | |
1070 | unsigned max_sz = UBLK_MAX_QUEUE_DEPTH * sizeof(struct ublksrv_io_desc); | |
1071 | unsigned long pfn, end, phys_off = vma->vm_pgoff << PAGE_SHIFT; | |
1072 | int q_id, ret = 0; | |
1073 | ||
e94eb459 | 1074 | spin_lock(&ub->mm_lock); |
71f28f31 ML |
1075 | if (!ub->mm) |
1076 | ub->mm = current->mm; | |
1077 | if (current->mm != ub->mm) | |
1078 | ret = -EINVAL; | |
e94eb459 | 1079 | spin_unlock(&ub->mm_lock); |
71f28f31 ML |
1080 | |
1081 | if (ret) | |
1082 | return ret; | |
1083 | ||
1084 | if (vma->vm_flags & VM_WRITE) | |
1085 | return -EPERM; | |
1086 | ||
1087 | end = UBLKSRV_CMD_BUF_OFFSET + ub->dev_info.nr_hw_queues * max_sz; | |
1088 | if (phys_off < UBLKSRV_CMD_BUF_OFFSET || phys_off >= end) | |
1089 | return -EINVAL; | |
1090 | ||
1091 | q_id = (phys_off - UBLKSRV_CMD_BUF_OFFSET) / max_sz; | |
1092 | pr_devel("%s: qid %d, pid %d, addr %lx pg_off %lx sz %lu\n", | |
1093 | __func__, q_id, current->pid, vma->vm_start, | |
1094 | phys_off, (unsigned long)sz); | |
1095 | ||
1096 | if (sz != ublk_queue_cmd_buf_size(ub, q_id)) | |
1097 | return -EINVAL; | |
1098 | ||
1099 | pfn = virt_to_phys(ublk_queue_cmd_buf(ub, q_id)) >> PAGE_SHIFT; | |
1100 | return remap_pfn_range(vma, vma->vm_start, pfn, sz, vma->vm_page_prot); | |
1101 | } | |
1102 | ||
1103 | static void ublk_commit_completion(struct ublk_device *ub, | |
fd9b8547 | 1104 | const struct ublksrv_io_cmd *ub_cmd) |
71f28f31 ML |
1105 | { |
1106 | u32 qid = ub_cmd->q_id, tag = ub_cmd->tag; | |
1107 | struct ublk_queue *ubq = ublk_get_queue(ub, qid); | |
1108 | struct ublk_io *io = &ubq->ios[tag]; | |
1109 | struct request *req; | |
1110 | ||
1111 | /* now this cmd slot is owned by nbd driver */ | |
1112 | io->flags &= ~UBLK_IO_FLAG_OWNED_BY_SRV; | |
1113 | io->res = ub_cmd->result; | |
1114 | ||
1115 | /* find the io request and complete */ | |
1116 | req = blk_mq_tag_to_rq(ub->tag_set.tags[qid], tag); | |
1117 | ||
1118 | if (req && likely(!blk_should_fake_timeout(req->q))) | |
82840669 | 1119 | ublk_put_req_ref(ubq, req); |
71f28f31 ML |
1120 | } |
1121 | ||
1122 | /* | |
1123 | * When ->ubq_daemon is exiting, either new request is ended immediately, | |
1124 | * or any queued io command is drained, so it is safe to abort queue | |
1125 | * lockless | |
1126 | */ | |
1127 | static void ublk_abort_queue(struct ublk_device *ub, struct ublk_queue *ubq) | |
1128 | { | |
1129 | int i; | |
1130 | ||
1131 | if (!ublk_get_device(ub)) | |
1132 | return; | |
1133 | ||
1134 | for (i = 0; i < ubq->q_depth; i++) { | |
1135 | struct ublk_io *io = &ubq->ios[i]; | |
1136 | ||
1137 | if (!(io->flags & UBLK_IO_FLAG_ACTIVE)) { | |
1138 | struct request *rq; | |
1139 | ||
1140 | /* | |
1141 | * Either we fail the request or ublk_rq_task_work_fn | |
1142 | * will do it | |
1143 | */ | |
1144 | rq = blk_mq_tag_to_rq(ub->tag_set.tags[ubq->q_id], i); | |
1145 | if (rq) | |
a0d41dc1 | 1146 | __ublk_fail_req(ubq, io, rq); |
71f28f31 ML |
1147 | } |
1148 | } | |
1149 | ublk_put_device(ub); | |
1150 | } | |
1151 | ||
1152 | static void ublk_daemon_monitor_work(struct work_struct *work) | |
1153 | { | |
1154 | struct ublk_device *ub = | |
1155 | container_of(work, struct ublk_device, monitor_work.work); | |
1156 | int i; | |
1157 | ||
1158 | for (i = 0; i < ub->dev_info.nr_hw_queues; i++) { | |
1159 | struct ublk_queue *ubq = ublk_get_queue(ub, i); | |
1160 | ||
1161 | if (ubq_daemon_is_dying(ubq)) { | |
bbae8d1f Z |
1162 | if (ublk_queue_can_use_recovery(ubq)) |
1163 | schedule_work(&ub->quiesce_work); | |
1164 | else | |
1165 | schedule_work(&ub->stop_work); | |
71f28f31 ML |
1166 | |
1167 | /* abort queue is for making forward progress */ | |
1168 | ublk_abort_queue(ub, ubq); | |
1169 | } | |
1170 | } | |
1171 | ||
1172 | /* | |
bbae8d1f Z |
1173 | * We can't schedule monitor work after ub's state is not UBLK_S_DEV_LIVE. |
1174 | * after ublk_remove() or __ublk_quiesce_dev() is started. | |
71f28f31 ML |
1175 | * |
1176 | * No need ub->mutex, monitor work are canceled after state is marked | |
bbae8d1f | 1177 | * as not LIVE, so new state is observed reliably. |
71f28f31 | 1178 | */ |
bbae8d1f | 1179 | if (ub->dev_info.state == UBLK_S_DEV_LIVE) |
71f28f31 ML |
1180 | schedule_delayed_work(&ub->monitor_work, |
1181 | UBLK_DAEMON_MONITOR_PERIOD); | |
1182 | } | |
1183 | ||
a8ce5f52 ML |
1184 | static inline bool ublk_queue_ready(struct ublk_queue *ubq) |
1185 | { | |
1186 | return ubq->nr_io_ready == ubq->q_depth; | |
1187 | } | |
1188 | ||
ac5902f8 ML |
1189 | static void ublk_cmd_cancel_cb(struct io_uring_cmd *cmd, unsigned issue_flags) |
1190 | { | |
1191 | io_uring_cmd_done(cmd, UBLK_IO_RES_ABORT, 0, issue_flags); | |
1192 | } | |
1193 | ||
71f28f31 ML |
1194 | static void ublk_cancel_queue(struct ublk_queue *ubq) |
1195 | { | |
1196 | int i; | |
1197 | ||
a8ce5f52 ML |
1198 | if (!ublk_queue_ready(ubq)) |
1199 | return; | |
1200 | ||
71f28f31 ML |
1201 | for (i = 0; i < ubq->q_depth; i++) { |
1202 | struct ublk_io *io = &ubq->ios[i]; | |
1203 | ||
1204 | if (io->flags & UBLK_IO_FLAG_ACTIVE) | |
ac5902f8 ML |
1205 | io_uring_cmd_complete_in_task(io->cmd, |
1206 | ublk_cmd_cancel_cb); | |
71f28f31 | 1207 | } |
a8ce5f52 ML |
1208 | |
1209 | /* all io commands are canceled */ | |
1210 | ubq->nr_io_ready = 0; | |
71f28f31 ML |
1211 | } |
1212 | ||
1213 | /* Cancel all pending commands, must be called after del_gendisk() returns */ | |
1214 | static void ublk_cancel_dev(struct ublk_device *ub) | |
1215 | { | |
1216 | int i; | |
1217 | ||
1218 | for (i = 0; i < ub->dev_info.nr_hw_queues; i++) | |
1219 | ublk_cancel_queue(ublk_get_queue(ub, i)); | |
1220 | } | |
1221 | ||
bbae8d1f Z |
1222 | static bool ublk_check_inflight_rq(struct request *rq, void *data) |
1223 | { | |
1224 | bool *idle = data; | |
1225 | ||
1226 | if (blk_mq_request_started(rq)) { | |
1227 | *idle = false; | |
1228 | return false; | |
1229 | } | |
1230 | return true; | |
1231 | } | |
1232 | ||
1233 | static void ublk_wait_tagset_rqs_idle(struct ublk_device *ub) | |
1234 | { | |
1235 | bool idle; | |
1236 | ||
1237 | WARN_ON_ONCE(!blk_queue_quiesced(ub->ub_disk->queue)); | |
1238 | while (true) { | |
1239 | idle = true; | |
1240 | blk_mq_tagset_busy_iter(&ub->tag_set, | |
1241 | ublk_check_inflight_rq, &idle); | |
1242 | if (idle) | |
1243 | break; | |
1244 | msleep(UBLK_REQUEUE_DELAY_MS); | |
1245 | } | |
1246 | } | |
1247 | ||
1248 | static void __ublk_quiesce_dev(struct ublk_device *ub) | |
71f28f31 | 1249 | { |
bbae8d1f Z |
1250 | pr_devel("%s: quiesce ub: dev_id %d state %s\n", |
1251 | __func__, ub->dev_info.dev_id, | |
1252 | ub->dev_info.state == UBLK_S_DEV_LIVE ? | |
1253 | "LIVE" : "QUIESCED"); | |
1254 | blk_mq_quiesce_queue(ub->ub_disk->queue); | |
1255 | ublk_wait_tagset_rqs_idle(ub); | |
1256 | ub->dev_info.state = UBLK_S_DEV_QUIESCED; | |
1257 | ublk_cancel_dev(ub); | |
1258 | /* we are going to release task_struct of ubq_daemon and resets | |
1259 | * ->ubq_daemon to NULL. So in monitor_work, check on ubq_daemon causes UAF. | |
1260 | * Besides, monitor_work is not necessary in QUIESCED state since we have | |
1261 | * already scheduled quiesce_work and quiesced all ubqs. | |
1262 | * | |
1263 | * Do not let monitor_work schedule itself if state it QUIESCED. And we cancel | |
1264 | * it here and re-schedule it in END_USER_RECOVERY to avoid UAF. | |
1265 | */ | |
1266 | cancel_delayed_work_sync(&ub->monitor_work); | |
1267 | } | |
1268 | ||
1269 | static void ublk_quiesce_work_fn(struct work_struct *work) | |
1270 | { | |
1271 | struct ublk_device *ub = | |
1272 | container_of(work, struct ublk_device, quiesce_work); | |
1273 | ||
71f28f31 | 1274 | mutex_lock(&ub->mutex); |
6d9e6dfd | 1275 | if (ub->dev_info.state != UBLK_S_DEV_LIVE) |
71f28f31 | 1276 | goto unlock; |
bbae8d1f Z |
1277 | __ublk_quiesce_dev(ub); |
1278 | unlock: | |
1279 | mutex_unlock(&ub->mutex); | |
1280 | } | |
71f28f31 | 1281 | |
bbae8d1f Z |
1282 | static void ublk_unquiesce_dev(struct ublk_device *ub) |
1283 | { | |
1284 | int i; | |
1285 | ||
1286 | pr_devel("%s: unquiesce ub: dev_id %d state %s\n", | |
1287 | __func__, ub->dev_info.dev_id, | |
1288 | ub->dev_info.state == UBLK_S_DEV_LIVE ? | |
1289 | "LIVE" : "QUIESCED"); | |
1290 | /* quiesce_work has run. We let requeued rqs be aborted | |
1291 | * before running fallback_wq. "force_abort" must be seen | |
1292 | * after request queue is unqiuesced. Then del_gendisk() | |
1293 | * can move on. | |
1294 | */ | |
1295 | for (i = 0; i < ub->dev_info.nr_hw_queues; i++) | |
1296 | ublk_get_queue(ub, i)->force_abort = true; | |
1297 | ||
1298 | blk_mq_unquiesce_queue(ub->ub_disk->queue); | |
1299 | /* We may have requeued some rqs in ublk_quiesce_queue() */ | |
1300 | blk_mq_kick_requeue_list(ub->ub_disk->queue); | |
1301 | } | |
1302 | ||
1303 | static void ublk_stop_dev(struct ublk_device *ub) | |
1304 | { | |
1305 | mutex_lock(&ub->mutex); | |
1306 | if (ub->dev_info.state == UBLK_S_DEV_DEAD) | |
1307 | goto unlock; | |
1308 | if (ublk_can_use_recovery(ub)) { | |
1309 | if (ub->dev_info.state == UBLK_S_DEV_LIVE) | |
1310 | __ublk_quiesce_dev(ub); | |
1311 | ublk_unquiesce_dev(ub); | |
1312 | } | |
71f28f31 ML |
1313 | del_gendisk(ub->ub_disk); |
1314 | ub->dev_info.state = UBLK_S_DEV_DEAD; | |
1315 | ub->dev_info.ublksrv_pid = -1; | |
6d9e6dfd CH |
1316 | put_disk(ub->ub_disk); |
1317 | ub->ub_disk = NULL; | |
71f28f31 | 1318 | unlock: |
a8ce5f52 | 1319 | ublk_cancel_dev(ub); |
71f28f31 ML |
1320 | mutex_unlock(&ub->mutex); |
1321 | cancel_delayed_work_sync(&ub->monitor_work); | |
1322 | } | |
1323 | ||
71f28f31 ML |
1324 | /* device can only be started after all IOs are ready */ |
1325 | static void ublk_mark_io_ready(struct ublk_device *ub, struct ublk_queue *ubq) | |
1326 | { | |
1327 | mutex_lock(&ub->mutex); | |
1328 | ubq->nr_io_ready++; | |
1329 | if (ublk_queue_ready(ubq)) { | |
1330 | ubq->ubq_daemon = current; | |
1331 | get_task_struct(ubq->ubq_daemon); | |
1332 | ub->nr_queues_ready++; | |
73a166d9 ML |
1333 | |
1334 | if (capable(CAP_SYS_ADMIN)) | |
1335 | ub->nr_privileged_daemon++; | |
71f28f31 ML |
1336 | } |
1337 | if (ub->nr_queues_ready == ub->dev_info.nr_hw_queues) | |
1338 | complete_all(&ub->completion); | |
1339 | mutex_unlock(&ub->mutex); | |
1340 | } | |
1341 | ||
c86019ff | 1342 | static void ublk_handle_need_get_data(struct ublk_device *ub, int q_id, |
fee32f31 | 1343 | int tag) |
c86019ff Z |
1344 | { |
1345 | struct ublk_queue *ubq = ublk_get_queue(ub, q_id); | |
1346 | struct request *req = blk_mq_tag_to_rq(ub->tag_set.tags[q_id], tag); | |
1347 | ||
7d4a9317 | 1348 | ublk_queue_cmd(ubq, req); |
c86019ff Z |
1349 | } |
1350 | ||
2d786e66 ML |
1351 | static inline int ublk_check_cmd_op(u32 cmd_op) |
1352 | { | |
1353 | u32 ioc_type = _IOC_TYPE(cmd_op); | |
1354 | ||
e485bd9e | 1355 | if (!IS_ENABLED(CONFIG_BLKDEV_UBLK_LEGACY_OPCODES) && ioc_type != 'u') |
2d786e66 ML |
1356 | return -EOPNOTSUPP; |
1357 | ||
1358 | if (ioc_type != 'u' && ioc_type != 0) | |
1359 | return -EOPNOTSUPP; | |
1360 | ||
1361 | return 0; | |
1362 | } | |
1363 | ||
f236a214 ML |
1364 | static inline void ublk_fill_io_cmd(struct ublk_io *io, |
1365 | struct io_uring_cmd *cmd, unsigned long buf_addr) | |
1366 | { | |
1367 | io->cmd = cmd; | |
1368 | io->flags |= UBLK_IO_FLAG_ACTIVE; | |
1369 | io->addr = buf_addr; | |
1370 | } | |
1371 | ||
8c68ae3b JA |
1372 | static int __ublk_ch_uring_cmd(struct io_uring_cmd *cmd, |
1373 | unsigned int issue_flags, | |
03e5cb7b | 1374 | const struct ublksrv_io_cmd *ub_cmd) |
71f28f31 | 1375 | { |
71f28f31 ML |
1376 | struct ublk_device *ub = cmd->file->private_data; |
1377 | struct ublk_queue *ubq; | |
1378 | struct ublk_io *io; | |
1379 | u32 cmd_op = cmd->cmd_op; | |
1380 | unsigned tag = ub_cmd->tag; | |
1381 | int ret = -EINVAL; | |
2f1e07dd | 1382 | struct request *req; |
71f28f31 ML |
1383 | |
1384 | pr_devel("%s: received: cmd op %d queue %d tag %d result %d\n", | |
1385 | __func__, cmd->cmd_op, ub_cmd->q_id, tag, | |
1386 | ub_cmd->result); | |
1387 | ||
71f28f31 ML |
1388 | if (ub_cmd->q_id >= ub->dev_info.nr_hw_queues) |
1389 | goto out; | |
1390 | ||
1391 | ubq = ublk_get_queue(ub, ub_cmd->q_id); | |
1392 | if (!ubq || ub_cmd->q_id != ubq->q_id) | |
1393 | goto out; | |
1394 | ||
1395 | if (ubq->ubq_daemon && ubq->ubq_daemon != current) | |
1396 | goto out; | |
1397 | ||
1398 | if (tag >= ubq->q_depth) | |
1399 | goto out; | |
1400 | ||
1401 | io = &ubq->ios[tag]; | |
1402 | ||
1403 | /* there is pending io cmd, something must be wrong */ | |
1404 | if (io->flags & UBLK_IO_FLAG_ACTIVE) { | |
1405 | ret = -EBUSY; | |
1406 | goto out; | |
1407 | } | |
1408 | ||
c86019ff Z |
1409 | /* |
1410 | * ensure that the user issues UBLK_IO_NEED_GET_DATA | |
1411 | * iff the driver have set the UBLK_IO_FLAG_NEED_GET_DATA. | |
1412 | */ | |
1413 | if ((!!(io->flags & UBLK_IO_FLAG_NEED_GET_DATA)) | |
2d786e66 ML |
1414 | ^ (_IOC_NR(cmd_op) == UBLK_IO_NEED_GET_DATA)) |
1415 | goto out; | |
1416 | ||
1172d5b8 ML |
1417 | if (ublk_support_user_copy(ubq) && ub_cmd->addr) { |
1418 | ret = -EINVAL; | |
1419 | goto out; | |
1420 | } | |
1421 | ||
2d786e66 ML |
1422 | ret = ublk_check_cmd_op(cmd_op); |
1423 | if (ret) | |
c86019ff Z |
1424 | goto out; |
1425 | ||
7c75661c | 1426 | ret = -EINVAL; |
2d786e66 | 1427 | switch (_IOC_NR(cmd_op)) { |
71f28f31 ML |
1428 | case UBLK_IO_FETCH_REQ: |
1429 | /* UBLK_IO_FETCH_REQ is only allowed before queue is setup */ | |
1430 | if (ublk_queue_ready(ubq)) { | |
1431 | ret = -EBUSY; | |
1432 | goto out; | |
1433 | } | |
1434 | /* | |
1435 | * The io is being handled by server, so COMMIT_RQ is expected | |
1436 | * instead of FETCH_REQ | |
1437 | */ | |
1438 | if (io->flags & UBLK_IO_FLAG_OWNED_BY_SRV) | |
1439 | goto out; | |
71f28f31 | 1440 | |
1172d5b8 ML |
1441 | if (!ublk_support_user_copy(ubq)) { |
1442 | /* | |
1443 | * FETCH_RQ has to provide IO buffer if NEED GET | |
1444 | * DATA is not enabled | |
1445 | */ | |
1446 | if (!ub_cmd->addr && !ublk_need_get_data(ubq)) | |
1447 | goto out; | |
1448 | } | |
71f28f31 | 1449 | |
f236a214 | 1450 | ublk_fill_io_cmd(io, cmd, ub_cmd->addr); |
71f28f31 ML |
1451 | ublk_mark_io_ready(ub, ubq); |
1452 | break; | |
1453 | case UBLK_IO_COMMIT_AND_FETCH_REQ: | |
2f1e07dd | 1454 | req = blk_mq_tag_to_rq(ub->tag_set.tags[ub_cmd->q_id], tag); |
1172d5b8 | 1455 | |
71f28f31 ML |
1456 | if (!(io->flags & UBLK_IO_FLAG_OWNED_BY_SRV)) |
1457 | goto out; | |
1172d5b8 ML |
1458 | |
1459 | if (!ublk_support_user_copy(ubq)) { | |
1460 | /* | |
1461 | * COMMIT_AND_FETCH_REQ has to provide IO buffer if | |
1462 | * NEED GET DATA is not enabled or it is Read IO. | |
1463 | */ | |
1464 | if (!ub_cmd->addr && (!ublk_need_get_data(ubq) || | |
1465 | req_op(req) == REQ_OP_READ)) | |
1466 | goto out; | |
1467 | } | |
f236a214 | 1468 | ublk_fill_io_cmd(io, cmd, ub_cmd->addr); |
71f28f31 ML |
1469 | ublk_commit_completion(ub, ub_cmd); |
1470 | break; | |
c86019ff Z |
1471 | case UBLK_IO_NEED_GET_DATA: |
1472 | if (!(io->flags & UBLK_IO_FLAG_OWNED_BY_SRV)) | |
1473 | goto out; | |
f236a214 | 1474 | ublk_fill_io_cmd(io, cmd, ub_cmd->addr); |
fee32f31 | 1475 | ublk_handle_need_get_data(ub, ub_cmd->q_id, ub_cmd->tag); |
c86019ff | 1476 | break; |
71f28f31 ML |
1477 | default: |
1478 | goto out; | |
1479 | } | |
1480 | return -EIOCBQUEUED; | |
1481 | ||
1482 | out: | |
9d2789ac | 1483 | io_uring_cmd_done(cmd, ret, 0, issue_flags); |
71f28f31 ML |
1484 | pr_devel("%s: complete: cmd op %d, tag %d ret %x io_flags %x\n", |
1485 | __func__, cmd_op, tag, ret, io->flags); | |
1486 | return -EIOCBQUEUED; | |
1487 | } | |
1488 | ||
62fe99ce ML |
1489 | static inline struct request *__ublk_check_and_get_req(struct ublk_device *ub, |
1490 | struct ublk_queue *ubq, int tag, size_t offset) | |
1491 | { | |
1492 | struct request *req; | |
1493 | ||
1494 | if (!ublk_need_req_ref(ubq)) | |
1495 | return NULL; | |
1496 | ||
1497 | req = blk_mq_tag_to_rq(ub->tag_set.tags[ubq->q_id], tag); | |
1498 | if (!req) | |
1499 | return NULL; | |
1500 | ||
1501 | if (!ublk_get_req_ref(ubq, req)) | |
1502 | return NULL; | |
1503 | ||
1504 | if (unlikely(!blk_mq_request_started(req) || req->tag != tag)) | |
1505 | goto fail_put; | |
1506 | ||
1507 | if (!ublk_rq_has_data(req)) | |
1508 | goto fail_put; | |
1509 | ||
1510 | if (offset > blk_rq_bytes(req)) | |
1511 | goto fail_put; | |
1512 | ||
1513 | return req; | |
1514 | fail_put: | |
1515 | ublk_put_req_ref(ubq, req); | |
1516 | return NULL; | |
1517 | } | |
1518 | ||
8c68ae3b JA |
1519 | static int ublk_ch_uring_cmd(struct io_uring_cmd *cmd, unsigned int issue_flags) |
1520 | { | |
8c68ae3b JA |
1521 | /* |
1522 | * Not necessary for async retry, but let's keep it simple and always | |
1523 | * copy the values to avoid any potential reuse. | |
1524 | */ | |
03e5cb7b LT |
1525 | const struct ublksrv_io_cmd *ub_src = io_uring_sqe_cmd(cmd->sqe); |
1526 | const struct ublksrv_io_cmd ub_cmd = { | |
1527 | .q_id = READ_ONCE(ub_src->q_id), | |
1528 | .tag = READ_ONCE(ub_src->tag), | |
1529 | .result = READ_ONCE(ub_src->result), | |
1530 | .addr = READ_ONCE(ub_src->addr) | |
1531 | }; | |
8c68ae3b JA |
1532 | |
1533 | return __ublk_ch_uring_cmd(cmd, issue_flags, &ub_cmd); | |
1534 | } | |
1535 | ||
62fe99ce ML |
1536 | static inline bool ublk_check_ubuf_dir(const struct request *req, |
1537 | int ubuf_dir) | |
1538 | { | |
1539 | /* copy ubuf to request pages */ | |
1540 | if (req_op(req) == REQ_OP_READ && ubuf_dir == ITER_SOURCE) | |
1541 | return true; | |
1542 | ||
1543 | /* copy request pages to ubuf */ | |
1544 | if (req_op(req) == REQ_OP_WRITE && ubuf_dir == ITER_DEST) | |
1545 | return true; | |
1546 | ||
1547 | return false; | |
1548 | } | |
1549 | ||
1550 | static struct request *ublk_check_and_get_req(struct kiocb *iocb, | |
1551 | struct iov_iter *iter, size_t *off, int dir) | |
1552 | { | |
1553 | struct ublk_device *ub = iocb->ki_filp->private_data; | |
1554 | struct ublk_queue *ubq; | |
1555 | struct request *req; | |
1556 | size_t buf_off; | |
1557 | u16 tag, q_id; | |
1558 | ||
1559 | if (!ub) | |
1560 | return ERR_PTR(-EACCES); | |
1561 | ||
1562 | if (!user_backed_iter(iter)) | |
1563 | return ERR_PTR(-EACCES); | |
1564 | ||
1565 | if (ub->dev_info.state == UBLK_S_DEV_DEAD) | |
1566 | return ERR_PTR(-EACCES); | |
1567 | ||
1568 | tag = ublk_pos_to_tag(iocb->ki_pos); | |
1569 | q_id = ublk_pos_to_hwq(iocb->ki_pos); | |
1570 | buf_off = ublk_pos_to_buf_off(iocb->ki_pos); | |
1571 | ||
1572 | if (q_id >= ub->dev_info.nr_hw_queues) | |
1573 | return ERR_PTR(-EINVAL); | |
1574 | ||
1575 | ubq = ublk_get_queue(ub, q_id); | |
1576 | if (!ubq) | |
1577 | return ERR_PTR(-EINVAL); | |
1578 | ||
1579 | if (tag >= ubq->q_depth) | |
1580 | return ERR_PTR(-EINVAL); | |
1581 | ||
1582 | req = __ublk_check_and_get_req(ub, ubq, tag, buf_off); | |
1583 | if (!req) | |
1584 | return ERR_PTR(-EINVAL); | |
1585 | ||
1586 | if (!req->mq_hctx || !req->mq_hctx->driver_data) | |
1587 | goto fail; | |
1588 | ||
1589 | if (!ublk_check_ubuf_dir(req, dir)) | |
1590 | goto fail; | |
1591 | ||
1592 | *off = buf_off; | |
1593 | return req; | |
1594 | fail: | |
1595 | ublk_put_req_ref(ubq, req); | |
1596 | return ERR_PTR(-EACCES); | |
1597 | } | |
1598 | ||
1599 | static ssize_t ublk_ch_read_iter(struct kiocb *iocb, struct iov_iter *to) | |
1600 | { | |
1601 | struct ublk_queue *ubq; | |
1602 | struct request *req; | |
1603 | size_t buf_off; | |
1604 | size_t ret; | |
1605 | ||
1606 | req = ublk_check_and_get_req(iocb, to, &buf_off, ITER_DEST); | |
1607 | if (IS_ERR(req)) | |
1608 | return PTR_ERR(req); | |
1609 | ||
1610 | ret = ublk_copy_user_pages(req, buf_off, to, ITER_DEST); | |
1611 | ubq = req->mq_hctx->driver_data; | |
1612 | ublk_put_req_ref(ubq, req); | |
1613 | ||
1614 | return ret; | |
1615 | } | |
1616 | ||
1617 | static ssize_t ublk_ch_write_iter(struct kiocb *iocb, struct iov_iter *from) | |
1618 | { | |
1619 | struct ublk_queue *ubq; | |
1620 | struct request *req; | |
1621 | size_t buf_off; | |
1622 | size_t ret; | |
1623 | ||
1624 | req = ublk_check_and_get_req(iocb, from, &buf_off, ITER_SOURCE); | |
1625 | if (IS_ERR(req)) | |
1626 | return PTR_ERR(req); | |
1627 | ||
1628 | ret = ublk_copy_user_pages(req, buf_off, from, ITER_SOURCE); | |
1629 | ubq = req->mq_hctx->driver_data; | |
1630 | ublk_put_req_ref(ubq, req); | |
1631 | ||
1632 | return ret; | |
1633 | } | |
1634 | ||
71f28f31 ML |
1635 | static const struct file_operations ublk_ch_fops = { |
1636 | .owner = THIS_MODULE, | |
1637 | .open = ublk_ch_open, | |
1638 | .release = ublk_ch_release, | |
1639 | .llseek = no_llseek, | |
62fe99ce ML |
1640 | .read_iter = ublk_ch_read_iter, |
1641 | .write_iter = ublk_ch_write_iter, | |
71f28f31 ML |
1642 | .uring_cmd = ublk_ch_uring_cmd, |
1643 | .mmap = ublk_ch_mmap, | |
1644 | }; | |
1645 | ||
1646 | static void ublk_deinit_queue(struct ublk_device *ub, int q_id) | |
1647 | { | |
1648 | int size = ublk_queue_cmd_buf_size(ub, q_id); | |
1649 | struct ublk_queue *ubq = ublk_get_queue(ub, q_id); | |
1650 | ||
1651 | if (ubq->ubq_daemon) | |
1652 | put_task_struct(ubq->ubq_daemon); | |
1653 | if (ubq->io_cmd_buf) | |
1654 | free_pages((unsigned long)ubq->io_cmd_buf, get_order(size)); | |
1655 | } | |
1656 | ||
1657 | static int ublk_init_queue(struct ublk_device *ub, int q_id) | |
1658 | { | |
1659 | struct ublk_queue *ubq = ublk_get_queue(ub, q_id); | |
1660 | gfp_t gfp_flags = GFP_KERNEL | __GFP_ZERO; | |
1661 | void *ptr; | |
1662 | int size; | |
1663 | ||
6d8c5afc | 1664 | ubq->flags = ub->dev_info.flags; |
71f28f31 ML |
1665 | ubq->q_id = q_id; |
1666 | ubq->q_depth = ub->dev_info.queue_depth; | |
1667 | size = ublk_queue_cmd_buf_size(ub, q_id); | |
1668 | ||
1669 | ptr = (void *) __get_free_pages(gfp_flags, get_order(size)); | |
1670 | if (!ptr) | |
1671 | return -ENOMEM; | |
1672 | ||
1673 | ubq->io_cmd_buf = ptr; | |
1674 | ubq->dev = ub; | |
1675 | return 0; | |
1676 | } | |
1677 | ||
1678 | static void ublk_deinit_queues(struct ublk_device *ub) | |
1679 | { | |
1680 | int nr_queues = ub->dev_info.nr_hw_queues; | |
1681 | int i; | |
1682 | ||
1683 | if (!ub->__queues) | |
1684 | return; | |
1685 | ||
1686 | for (i = 0; i < nr_queues; i++) | |
1687 | ublk_deinit_queue(ub, i); | |
1688 | kfree(ub->__queues); | |
1689 | } | |
1690 | ||
1691 | static int ublk_init_queues(struct ublk_device *ub) | |
1692 | { | |
1693 | int nr_queues = ub->dev_info.nr_hw_queues; | |
1694 | int depth = ub->dev_info.queue_depth; | |
1695 | int ubq_size = sizeof(struct ublk_queue) + depth * sizeof(struct ublk_io); | |
1696 | int i, ret = -ENOMEM; | |
1697 | ||
1698 | ub->queue_size = ubq_size; | |
1699 | ub->__queues = kcalloc(nr_queues, ubq_size, GFP_KERNEL); | |
1700 | if (!ub->__queues) | |
1701 | return ret; | |
1702 | ||
1703 | for (i = 0; i < nr_queues; i++) { | |
1704 | if (ublk_init_queue(ub, i)) | |
1705 | goto fail; | |
1706 | } | |
1707 | ||
1708 | init_completion(&ub->completion); | |
1709 | return 0; | |
1710 | ||
1711 | fail: | |
1712 | ublk_deinit_queues(ub); | |
1713 | return ret; | |
1714 | } | |
1715 | ||
fa9482e0 | 1716 | static int ublk_alloc_dev_number(struct ublk_device *ub, int idx) |
71f28f31 ML |
1717 | { |
1718 | int i = idx; | |
1719 | int err; | |
1720 | ||
1721 | spin_lock(&ublk_idr_lock); | |
1722 | /* allocate id, if @id >= 0, we're requesting that specific id */ | |
1723 | if (i >= 0) { | |
1724 | err = idr_alloc(&ublk_index_idr, ub, i, i + 1, GFP_NOWAIT); | |
1725 | if (err == -ENOSPC) | |
1726 | err = -EEXIST; | |
1727 | } else { | |
1728 | err = idr_alloc(&ublk_index_idr, ub, 0, 0, GFP_NOWAIT); | |
1729 | } | |
1730 | spin_unlock(&ublk_idr_lock); | |
1731 | ||
1732 | if (err >= 0) | |
1733 | ub->ub_number = err; | |
1734 | ||
1735 | return err; | |
1736 | } | |
1737 | ||
fa9482e0 | 1738 | static void ublk_free_dev_number(struct ublk_device *ub) |
71f28f31 ML |
1739 | { |
1740 | spin_lock(&ublk_idr_lock); | |
1741 | idr_remove(&ublk_index_idr, ub->ub_number); | |
1742 | wake_up_all(&ublk_idr_wq); | |
1743 | spin_unlock(&ublk_idr_lock); | |
71f28f31 ML |
1744 | } |
1745 | ||
1746 | static void ublk_cdev_rel(struct device *dev) | |
1747 | { | |
1748 | struct ublk_device *ub = container_of(dev, struct ublk_device, cdev_dev); | |
1749 | ||
71f28f31 | 1750 | blk_mq_free_tag_set(&ub->tag_set); |
71f28f31 | 1751 | ublk_deinit_queues(ub); |
fa9482e0 CH |
1752 | ublk_free_dev_number(ub); |
1753 | mutex_destroy(&ub->mutex); | |
1754 | kfree(ub); | |
71f28f31 ML |
1755 | } |
1756 | ||
1757 | static int ublk_add_chdev(struct ublk_device *ub) | |
1758 | { | |
1759 | struct device *dev = &ub->cdev_dev; | |
1760 | int minor = ub->ub_number; | |
1761 | int ret; | |
1762 | ||
1763 | dev->parent = ublk_misc.this_device; | |
1764 | dev->devt = MKDEV(MAJOR(ublk_chr_devt), minor); | |
2eefd399 | 1765 | dev->class = &ublk_chr_class; |
71f28f31 ML |
1766 | dev->release = ublk_cdev_rel; |
1767 | device_initialize(dev); | |
1768 | ||
1769 | ret = dev_set_name(dev, "ublkc%d", minor); | |
1770 | if (ret) | |
1771 | goto fail; | |
1772 | ||
1773 | cdev_init(&ub->cdev, &ublk_ch_fops); | |
1774 | ret = cdev_device_add(&ub->cdev, dev); | |
1775 | if (ret) | |
1776 | goto fail; | |
403ebc87 ML |
1777 | |
1778 | ublks_added++; | |
71f28f31 ML |
1779 | return 0; |
1780 | fail: | |
1781 | put_device(dev); | |
1782 | return ret; | |
1783 | } | |
1784 | ||
1785 | static void ublk_stop_work_fn(struct work_struct *work) | |
1786 | { | |
1787 | struct ublk_device *ub = | |
1788 | container_of(work, struct ublk_device, stop_work); | |
1789 | ||
1790 | ublk_stop_dev(ub); | |
1791 | } | |
1792 | ||
4bf9cbf3 | 1793 | /* align max io buffer size with PAGE_SIZE */ |
6d9e6dfd | 1794 | static void ublk_align_max_io_size(struct ublk_device *ub) |
71f28f31 | 1795 | { |
4bf9cbf3 | 1796 | unsigned int max_io_bytes = ub->dev_info.max_io_buf_bytes; |
71f28f31 | 1797 | |
4bf9cbf3 ML |
1798 | ub->dev_info.max_io_buf_bytes = |
1799 | round_down(max_io_bytes, PAGE_SIZE); | |
71f28f31 ML |
1800 | } |
1801 | ||
fa9482e0 | 1802 | static int ublk_add_tag_set(struct ublk_device *ub) |
71f28f31 | 1803 | { |
71f28f31 ML |
1804 | ub->tag_set.ops = &ublk_mq_ops; |
1805 | ub->tag_set.nr_hw_queues = ub->dev_info.nr_hw_queues; | |
1806 | ub->tag_set.queue_depth = ub->dev_info.queue_depth; | |
1807 | ub->tag_set.numa_node = NUMA_NO_NODE; | |
0edb3696 | 1808 | ub->tag_set.cmd_size = sizeof(struct ublk_rq_data); |
71f28f31 ML |
1809 | ub->tag_set.flags = BLK_MQ_F_SHOULD_MERGE; |
1810 | ub->tag_set.driver_data = ub; | |
fa9482e0 | 1811 | return blk_mq_alloc_tag_set(&ub->tag_set); |
71f28f31 ML |
1812 | } |
1813 | ||
1814 | static void ublk_remove(struct ublk_device *ub) | |
1815 | { | |
34d8f2be CH |
1816 | ublk_stop_dev(ub); |
1817 | cancel_work_sync(&ub->stop_work); | |
bbae8d1f | 1818 | cancel_work_sync(&ub->quiesce_work); |
71f28f31 ML |
1819 | cdev_device_del(&ub->cdev, &ub->cdev_dev); |
1820 | put_device(&ub->cdev_dev); | |
403ebc87 | 1821 | ublks_added--; |
71f28f31 ML |
1822 | } |
1823 | ||
1824 | static struct ublk_device *ublk_get_device_from_id(int idx) | |
1825 | { | |
1826 | struct ublk_device *ub = NULL; | |
1827 | ||
1828 | if (idx < 0) | |
1829 | return NULL; | |
1830 | ||
1831 | spin_lock(&ublk_idr_lock); | |
1832 | ub = idr_find(&ublk_index_idr, idx); | |
1833 | if (ub) | |
1834 | ub = ublk_get_device(ub); | |
1835 | spin_unlock(&ublk_idr_lock); | |
1836 | ||
1837 | return ub; | |
1838 | } | |
1839 | ||
bfbcef03 | 1840 | static int ublk_ctrl_start_dev(struct ublk_device *ub, struct io_uring_cmd *cmd) |
71f28f31 | 1841 | { |
fd9b8547 | 1842 | const struct ublksrv_ctrl_cmd *header = io_uring_sqe_cmd(cmd->sqe); |
71f28f31 | 1843 | int ublksrv_pid = (int)header->data[0]; |
6d9e6dfd | 1844 | struct gendisk *disk; |
34d8f2be | 1845 | int ret = -EINVAL; |
71f28f31 ML |
1846 | |
1847 | if (ublksrv_pid <= 0) | |
34d8f2be CH |
1848 | return -EINVAL; |
1849 | ||
71f28f31 ML |
1850 | wait_for_completion_interruptible(&ub->completion); |
1851 | ||
1852 | schedule_delayed_work(&ub->monitor_work, UBLK_DAEMON_MONITOR_PERIOD); | |
1853 | ||
1854 | mutex_lock(&ub->mutex); | |
6d9e6dfd CH |
1855 | if (ub->dev_info.state == UBLK_S_DEV_LIVE || |
1856 | test_bit(UB_STATE_USED, &ub->state)) { | |
71f28f31 | 1857 | ret = -EEXIST; |
34d8f2be | 1858 | goto out_unlock; |
71f28f31 | 1859 | } |
71f28f31 | 1860 | |
1972d038 | 1861 | disk = blk_mq_alloc_disk(&ub->tag_set, NULL); |
6d9e6dfd CH |
1862 | if (IS_ERR(disk)) { |
1863 | ret = PTR_ERR(disk); | |
1864 | goto out_unlock; | |
34d8f2be | 1865 | } |
6d9e6dfd CH |
1866 | sprintf(disk->disk_name, "ublkb%d", ub->ub_number); |
1867 | disk->fops = &ub_fops; | |
1868 | disk->private_data = ub; | |
1869 | ||
34d8f2be | 1870 | ub->dev_info.ublksrv_pid = ublksrv_pid; |
6d9e6dfd | 1871 | ub->ub_disk = disk; |
0aa73170 ML |
1872 | |
1873 | ret = ublk_apply_params(ub); | |
1874 | if (ret) | |
1875 | goto out_put_disk; | |
1876 | ||
73a166d9 ML |
1877 | /* don't probe partitions if any one ubq daemon is un-trusted */ |
1878 | if (ub->nr_privileged_daemon != ub->nr_queues_ready) | |
1879 | set_bit(GD_SUPPRESS_PART_SCAN, &disk->state); | |
1880 | ||
6d9e6dfd | 1881 | get_device(&ub->cdev_dev); |
4985e7b2 | 1882 | ub->dev_info.state = UBLK_S_DEV_LIVE; |
6d9e6dfd CH |
1883 | ret = add_disk(disk); |
1884 | if (ret) { | |
93d71ec8 ML |
1885 | /* |
1886 | * Has to drop the reference since ->free_disk won't be | |
1887 | * called in case of add_disk failure. | |
1888 | */ | |
4985e7b2 | 1889 | ub->dev_info.state = UBLK_S_DEV_DEAD; |
93d71ec8 | 1890 | ublk_put_device(ub); |
0aa73170 | 1891 | goto out_put_disk; |
6d9e6dfd CH |
1892 | } |
1893 | set_bit(UB_STATE_USED, &ub->state); | |
0aa73170 ML |
1894 | out_put_disk: |
1895 | if (ret) | |
1896 | put_disk(disk); | |
34d8f2be CH |
1897 | out_unlock: |
1898 | mutex_unlock(&ub->mutex); | |
71f28f31 ML |
1899 | return ret; |
1900 | } | |
1901 | ||
bfbcef03 ML |
1902 | static int ublk_ctrl_get_queue_affinity(struct ublk_device *ub, |
1903 | struct io_uring_cmd *cmd) | |
71f28f31 | 1904 | { |
fd9b8547 | 1905 | const struct ublksrv_ctrl_cmd *header = io_uring_sqe_cmd(cmd->sqe); |
71f28f31 | 1906 | void __user *argp = (void __user *)(unsigned long)header->addr; |
c50061f0 | 1907 | cpumask_var_t cpumask; |
71f28f31 ML |
1908 | unsigned long queue; |
1909 | unsigned int retlen; | |
c50061f0 | 1910 | unsigned int i; |
bfbcef03 ML |
1911 | int ret; |
1912 | ||
34d8f2be CH |
1913 | if (header->len * BITS_PER_BYTE < nr_cpu_ids) |
1914 | return -EINVAL; | |
1915 | if (header->len & (sizeof(unsigned long)-1)) | |
1916 | return -EINVAL; | |
1917 | if (!header->addr) | |
1918 | return -EINVAL; | |
71f28f31 | 1919 | |
71f28f31 ML |
1920 | queue = header->data[0]; |
1921 | if (queue >= ub->dev_info.nr_hw_queues) | |
bfbcef03 | 1922 | return -EINVAL; |
71f28f31 | 1923 | |
c50061f0 | 1924 | if (!zalloc_cpumask_var(&cpumask, GFP_KERNEL)) |
bfbcef03 | 1925 | return -ENOMEM; |
c50061f0 CH |
1926 | |
1927 | for_each_possible_cpu(i) { | |
1928 | if (ub->tag_set.map[HCTX_TYPE_DEFAULT].mq_map[i] == queue) | |
1929 | cpumask_set_cpu(i, cpumask); | |
71f28f31 | 1930 | } |
c50061f0 CH |
1931 | |
1932 | ret = -EFAULT; | |
1933 | retlen = min_t(unsigned short, header->len, cpumask_size()); | |
1934 | if (copy_to_user(argp, cpumask, retlen)) | |
1935 | goto out_free_cpumask; | |
1936 | if (retlen != header->len && | |
1937 | clear_user(argp + retlen, header->len - retlen)) | |
1938 | goto out_free_cpumask; | |
1939 | ||
71f28f31 | 1940 | ret = 0; |
c50061f0 CH |
1941 | out_free_cpumask: |
1942 | free_cpumask_var(cpumask); | |
71f28f31 ML |
1943 | return ret; |
1944 | } | |
1945 | ||
34d8f2be | 1946 | static inline void ublk_dump_dev_info(struct ublksrv_ctrl_dev_info *info) |
71f28f31 | 1947 | { |
34d8f2be | 1948 | pr_devel("%s: dev id %d flags %llx\n", __func__, |
6d8c5afc | 1949 | info->dev_id, info->flags); |
4bf9cbf3 ML |
1950 | pr_devel("\t nr_hw_queues %d queue_depth %d\n", |
1951 | info->nr_hw_queues, info->queue_depth); | |
34d8f2be CH |
1952 | } |
1953 | ||
1954 | static int ublk_ctrl_add_dev(struct io_uring_cmd *cmd) | |
1955 | { | |
fd9b8547 | 1956 | const struct ublksrv_ctrl_cmd *header = io_uring_sqe_cmd(cmd->sqe); |
34d8f2be CH |
1957 | void __user *argp = (void __user *)(unsigned long)header->addr; |
1958 | struct ublksrv_ctrl_dev_info info; | |
71f28f31 | 1959 | struct ublk_device *ub; |
34d8f2be CH |
1960 | int ret = -EINVAL; |
1961 | ||
1962 | if (header->len < sizeof(info) || !header->addr) | |
1963 | return -EINVAL; | |
1964 | if (header->queue_id != (u16)-1) { | |
1965 | pr_warn("%s: queue_id is wrong %x\n", | |
1966 | __func__, header->queue_id); | |
1967 | return -EINVAL; | |
1968 | } | |
4093cb5a | 1969 | |
34d8f2be CH |
1970 | if (copy_from_user(&info, argp, sizeof(info))) |
1971 | return -EFAULT; | |
4093cb5a ML |
1972 | |
1973 | if (capable(CAP_SYS_ADMIN)) | |
1974 | info.flags &= ~UBLK_F_UNPRIVILEGED_DEV; | |
1975 | else if (!(info.flags & UBLK_F_UNPRIVILEGED_DEV)) | |
1976 | return -EPERM; | |
1977 | ||
c0b79b0f ML |
1978 | /* |
1979 | * unprivileged device can't be trusted, but RECOVERY and | |
1980 | * RECOVERY_REISSUE still may hang error handling, so can't | |
1981 | * support recovery features for unprivileged ublk now | |
1982 | * | |
1983 | * TODO: provide forward progress for RECOVERY handler, so that | |
1984 | * unprivileged device can benefit from it | |
1985 | */ | |
1986 | if (info.flags & UBLK_F_UNPRIVILEGED_DEV) | |
1987 | info.flags &= ~(UBLK_F_USER_RECOVERY_REISSUE | | |
1988 | UBLK_F_USER_RECOVERY); | |
1989 | ||
4093cb5a | 1990 | /* the created device is always owned by current user */ |
48a90519 | 1991 | ublk_store_owner_uid_gid(&info.owner_uid, &info.owner_gid); |
4093cb5a | 1992 | |
34d8f2be CH |
1993 | if (header->dev_id != info.dev_id) { |
1994 | pr_warn("%s: dev id not match %u %u\n", | |
1995 | __func__, header->dev_id, info.dev_id); | |
1996 | return -EINVAL; | |
1997 | } | |
71f28f31 | 1998 | |
4093cb5a ML |
1999 | ublk_dump_dev_info(&info); |
2000 | ||
71f28f31 ML |
2001 | ret = mutex_lock_killable(&ublk_ctl_mutex); |
2002 | if (ret) | |
2003 | return ret; | |
2004 | ||
403ebc87 ML |
2005 | ret = -EACCES; |
2006 | if (ublks_added >= ublks_max) | |
2007 | goto out_unlock; | |
2008 | ||
cfee7e4d CH |
2009 | ret = -ENOMEM; |
2010 | ub = kzalloc(sizeof(*ub), GFP_KERNEL); | |
2011 | if (!ub) | |
2012 | goto out_unlock; | |
fa9482e0 CH |
2013 | mutex_init(&ub->mutex); |
2014 | spin_lock_init(&ub->mm_lock); | |
bbae8d1f | 2015 | INIT_WORK(&ub->quiesce_work, ublk_quiesce_work_fn); |
fa9482e0 CH |
2016 | INIT_WORK(&ub->stop_work, ublk_stop_work_fn); |
2017 | INIT_DELAYED_WORK(&ub->monitor_work, ublk_daemon_monitor_work); | |
cfee7e4d | 2018 | |
fa9482e0 CH |
2019 | ret = ublk_alloc_dev_number(ub, header->dev_id); |
2020 | if (ret < 0) | |
2021 | goto out_free_ub; | |
71f28f31 | 2022 | |
34d8f2be | 2023 | memcpy(&ub->dev_info, &info, sizeof(info)); |
71f28f31 | 2024 | |
34d8f2be CH |
2025 | /* update device id */ |
2026 | ub->dev_info.dev_id = ub->ub_number; | |
2027 | ||
6d8c5afc ML |
2028 | /* |
2029 | * 64bit flags will be copied back to userspace as feature | |
2030 | * negotiation result, so have to clear flags which driver | |
2031 | * doesn't support yet, then userspace can get correct flags | |
2032 | * (features) to handle. | |
2033 | */ | |
2034 | ub->dev_info.flags &= UBLK_F_ALL; | |
2035 | ||
29dc5d06 ML |
2036 | ub->dev_info.flags |= UBLK_F_CMD_IOCTL_ENCODE | |
2037 | UBLK_F_URING_CMD_COMP_IN_TASK; | |
224e858f | 2038 | |
1172d5b8 ML |
2039 | /* GET_DATA isn't needed any more with USER_COPY */ |
2040 | if (ub->dev_info.flags & UBLK_F_USER_COPY) | |
2041 | ub->dev_info.flags &= ~UBLK_F_NEED_GET_DATA; | |
2d786e66 | 2042 | |
fa9482e0 | 2043 | /* We are not ready to support zero copy */ |
6d8c5afc | 2044 | ub->dev_info.flags &= ~UBLK_F_SUPPORT_ZERO_COPY; |
fa9482e0 | 2045 | |
fa9482e0 CH |
2046 | ub->dev_info.nr_hw_queues = min_t(unsigned int, |
2047 | ub->dev_info.nr_hw_queues, nr_cpu_ids); | |
2048 | ublk_align_max_io_size(ub); | |
2049 | ||
2050 | ret = ublk_init_queues(ub); | |
34d8f2be | 2051 | if (ret) |
fa9482e0 | 2052 | goto out_free_dev_number; |
34d8f2be | 2053 | |
fa9482e0 CH |
2054 | ret = ublk_add_tag_set(ub); |
2055 | if (ret) | |
2056 | goto out_deinit_queues; | |
2057 | ||
2058 | ret = -EFAULT; | |
2059 | if (copy_to_user(argp, &ub->dev_info, sizeof(info))) | |
2060 | goto out_free_tag_set; | |
2061 | ||
2062 | /* | |
2063 | * Add the char dev so that ublksrv daemon can be setup. | |
2064 | * ublk_add_chdev() will cleanup everything if it fails. | |
2065 | */ | |
2066 | ret = ublk_add_chdev(ub); | |
2067 | goto out_unlock; | |
2068 | ||
2069 | out_free_tag_set: | |
2070 | blk_mq_free_tag_set(&ub->tag_set); | |
2071 | out_deinit_queues: | |
2072 | ublk_deinit_queues(ub); | |
2073 | out_free_dev_number: | |
2074 | ublk_free_dev_number(ub); | |
2075 | out_free_ub: | |
2076 | mutex_destroy(&ub->mutex); | |
2077 | kfree(ub); | |
34d8f2be | 2078 | out_unlock: |
71f28f31 | 2079 | mutex_unlock(&ublk_ctl_mutex); |
71f28f31 ML |
2080 | return ret; |
2081 | } | |
2082 | ||
2083 | static inline bool ublk_idr_freed(int id) | |
2084 | { | |
2085 | void *ptr; | |
2086 | ||
2087 | spin_lock(&ublk_idr_lock); | |
2088 | ptr = idr_find(&ublk_index_idr, id); | |
2089 | spin_unlock(&ublk_idr_lock); | |
2090 | ||
2091 | return ptr == NULL; | |
2092 | } | |
2093 | ||
bfbcef03 | 2094 | static int ublk_ctrl_del_dev(struct ublk_device **p_ub) |
71f28f31 | 2095 | { |
bfbcef03 ML |
2096 | struct ublk_device *ub = *p_ub; |
2097 | int idx = ub->ub_number; | |
71f28f31 ML |
2098 | int ret; |
2099 | ||
2100 | ret = mutex_lock_killable(&ublk_ctl_mutex); | |
2101 | if (ret) | |
2102 | return ret; | |
2103 | ||
0abe39de | 2104 | if (!test_bit(UB_STATE_DELETED, &ub->state)) { |
71f28f31 | 2105 | ublk_remove(ub); |
0abe39de | 2106 | set_bit(UB_STATE_DELETED, &ub->state); |
71f28f31 ML |
2107 | } |
2108 | ||
bfbcef03 ML |
2109 | /* Mark the reference as consumed */ |
2110 | *p_ub = NULL; | |
2111 | ublk_put_device(ub); | |
0abe39de | 2112 | mutex_unlock(&ublk_ctl_mutex); |
71f28f31 ML |
2113 | |
2114 | /* | |
2115 | * Wait until the idr is removed, then it can be reused after | |
2116 | * DEL_DEV command is returned. | |
0abe39de ML |
2117 | * |
2118 | * If we returns because of user interrupt, future delete command | |
2119 | * may come: | |
2120 | * | |
2121 | * - the device number isn't freed, this device won't or needn't | |
2122 | * be deleted again, since UB_STATE_DELETED is set, and device | |
2123 | * will be released after the last reference is dropped | |
2124 | * | |
2125 | * - the device number is freed already, we will not find this | |
2126 | * device via ublk_get_device_from_id() | |
71f28f31 | 2127 | */ |
0abe39de | 2128 | wait_event_interruptible(ublk_idr_wq, ublk_idr_freed(idx)); |
71f28f31 | 2129 | |
0abe39de | 2130 | return 0; |
71f28f31 ML |
2131 | } |
2132 | ||
71f28f31 ML |
2133 | static inline void ublk_ctrl_cmd_dump(struct io_uring_cmd *cmd) |
2134 | { | |
fd9b8547 | 2135 | const struct ublksrv_ctrl_cmd *header = io_uring_sqe_cmd(cmd->sqe); |
71f28f31 ML |
2136 | |
2137 | pr_devel("%s: cmd_op %x, dev id %d qid %d data %llx buf %llx len %u\n", | |
2138 | __func__, cmd->cmd_op, header->dev_id, header->queue_id, | |
2139 | header->data[0], header->addr, header->len); | |
2140 | } | |
2141 | ||
bfbcef03 | 2142 | static int ublk_ctrl_stop_dev(struct ublk_device *ub) |
71f28f31 | 2143 | { |
34d8f2be CH |
2144 | ublk_stop_dev(ub); |
2145 | cancel_work_sync(&ub->stop_work); | |
bbae8d1f | 2146 | cancel_work_sync(&ub->quiesce_work); |
71f28f31 ML |
2147 | |
2148 | return 0; | |
2149 | } | |
2150 | ||
bfbcef03 ML |
2151 | static int ublk_ctrl_get_dev_info(struct ublk_device *ub, |
2152 | struct io_uring_cmd *cmd) | |
71f28f31 | 2153 | { |
fd9b8547 | 2154 | const struct ublksrv_ctrl_cmd *header = io_uring_sqe_cmd(cmd->sqe); |
71f28f31 | 2155 | void __user *argp = (void __user *)(unsigned long)header->addr; |
34d8f2be CH |
2156 | |
2157 | if (header->len < sizeof(struct ublksrv_ctrl_dev_info) || !header->addr) | |
2158 | return -EINVAL; | |
2159 | ||
34d8f2be | 2160 | if (copy_to_user(argp, &ub->dev_info, sizeof(ub->dev_info))) |
bfbcef03 | 2161 | return -EFAULT; |
34d8f2be | 2162 | |
bfbcef03 | 2163 | return 0; |
34d8f2be CH |
2164 | } |
2165 | ||
abb864d3 ML |
2166 | /* TYPE_DEVT is readonly, so fill it up before returning to userspace */ |
2167 | static void ublk_ctrl_fill_params_devt(struct ublk_device *ub) | |
2168 | { | |
2169 | ub->params.devt.char_major = MAJOR(ub->cdev_dev.devt); | |
2170 | ub->params.devt.char_minor = MINOR(ub->cdev_dev.devt); | |
2171 | ||
2172 | if (ub->ub_disk) { | |
2173 | ub->params.devt.disk_major = MAJOR(disk_devt(ub->ub_disk)); | |
2174 | ub->params.devt.disk_minor = MINOR(disk_devt(ub->ub_disk)); | |
2175 | } else { | |
2176 | ub->params.devt.disk_major = 0; | |
2177 | ub->params.devt.disk_minor = 0; | |
2178 | } | |
2179 | ub->params.types |= UBLK_PARAM_TYPE_DEVT; | |
34d8f2be CH |
2180 | } |
2181 | ||
bfbcef03 ML |
2182 | static int ublk_ctrl_get_params(struct ublk_device *ub, |
2183 | struct io_uring_cmd *cmd) | |
0aa73170 | 2184 | { |
fd9b8547 | 2185 | const struct ublksrv_ctrl_cmd *header = io_uring_sqe_cmd(cmd->sqe); |
0aa73170 ML |
2186 | void __user *argp = (void __user *)(unsigned long)header->addr; |
2187 | struct ublk_params_header ph; | |
0aa73170 ML |
2188 | int ret; |
2189 | ||
2190 | if (header->len <= sizeof(ph) || !header->addr) | |
2191 | return -EINVAL; | |
2192 | ||
2193 | if (copy_from_user(&ph, argp, sizeof(ph))) | |
2194 | return -EFAULT; | |
2195 | ||
2196 | if (ph.len > header->len || !ph.len) | |
2197 | return -EINVAL; | |
2198 | ||
2199 | if (ph.len > sizeof(struct ublk_params)) | |
2200 | ph.len = sizeof(struct ublk_params); | |
2201 | ||
0aa73170 | 2202 | mutex_lock(&ub->mutex); |
abb864d3 | 2203 | ublk_ctrl_fill_params_devt(ub); |
0aa73170 ML |
2204 | if (copy_to_user(argp, &ub->params, ph.len)) |
2205 | ret = -EFAULT; | |
2206 | else | |
2207 | ret = 0; | |
2208 | mutex_unlock(&ub->mutex); | |
2209 | ||
0aa73170 ML |
2210 | return ret; |
2211 | } | |
2212 | ||
bfbcef03 ML |
2213 | static int ublk_ctrl_set_params(struct ublk_device *ub, |
2214 | struct io_uring_cmd *cmd) | |
0aa73170 | 2215 | { |
fd9b8547 | 2216 | const struct ublksrv_ctrl_cmd *header = io_uring_sqe_cmd(cmd->sqe); |
0aa73170 ML |
2217 | void __user *argp = (void __user *)(unsigned long)header->addr; |
2218 | struct ublk_params_header ph; | |
0aa73170 ML |
2219 | int ret = -EFAULT; |
2220 | ||
2221 | if (header->len <= sizeof(ph) || !header->addr) | |
2222 | return -EINVAL; | |
2223 | ||
2224 | if (copy_from_user(&ph, argp, sizeof(ph))) | |
2225 | return -EFAULT; | |
2226 | ||
2227 | if (ph.len > header->len || !ph.len || !ph.types) | |
2228 | return -EINVAL; | |
2229 | ||
2230 | if (ph.len > sizeof(struct ublk_params)) | |
2231 | ph.len = sizeof(struct ublk_params); | |
2232 | ||
0aa73170 ML |
2233 | /* parameters can only be changed when device isn't live */ |
2234 | mutex_lock(&ub->mutex); | |
2235 | if (ub->dev_info.state == UBLK_S_DEV_LIVE) { | |
2236 | ret = -EACCES; | |
2237 | } else if (copy_from_user(&ub->params, argp, ph.len)) { | |
2238 | ret = -EFAULT; | |
2239 | } else { | |
2240 | /* clear all we don't support yet */ | |
2241 | ub->params.types &= UBLK_PARAM_TYPE_ALL; | |
2242 | ret = ublk_validate_params(ub); | |
1d166527 ML |
2243 | if (ret) |
2244 | ub->params.types = 0; | |
0aa73170 ML |
2245 | } |
2246 | mutex_unlock(&ub->mutex); | |
0aa73170 ML |
2247 | |
2248 | return ret; | |
2249 | } | |
2250 | ||
c732a852 Z |
2251 | static void ublk_queue_reinit(struct ublk_device *ub, struct ublk_queue *ubq) |
2252 | { | |
2253 | int i; | |
2254 | ||
2255 | WARN_ON_ONCE(!(ubq->ubq_daemon && ubq_daemon_is_dying(ubq))); | |
2256 | /* All old ioucmds have to be completed */ | |
2257 | WARN_ON_ONCE(ubq->nr_io_ready); | |
2258 | /* old daemon is PF_EXITING, put it now */ | |
2259 | put_task_struct(ubq->ubq_daemon); | |
2260 | /* We have to reset it to NULL, otherwise ub won't accept new FETCH_REQ */ | |
2261 | ubq->ubq_daemon = NULL; | |
c0b79b0f | 2262 | ubq->timeout = false; |
c732a852 Z |
2263 | |
2264 | for (i = 0; i < ubq->q_depth; i++) { | |
2265 | struct ublk_io *io = &ubq->ios[i]; | |
2266 | ||
2267 | /* forget everything now and be ready for new FETCH_REQ */ | |
2268 | io->flags = 0; | |
2269 | io->cmd = NULL; | |
2270 | io->addr = 0; | |
2271 | } | |
2272 | } | |
2273 | ||
bfbcef03 ML |
2274 | static int ublk_ctrl_start_recovery(struct ublk_device *ub, |
2275 | struct io_uring_cmd *cmd) | |
c732a852 | 2276 | { |
fd9b8547 | 2277 | const struct ublksrv_ctrl_cmd *header = io_uring_sqe_cmd(cmd->sqe); |
c732a852 Z |
2278 | int ret = -EINVAL; |
2279 | int i; | |
2280 | ||
c732a852 Z |
2281 | mutex_lock(&ub->mutex); |
2282 | if (!ublk_can_use_recovery(ub)) | |
2283 | goto out_unlock; | |
2284 | /* | |
2285 | * START_RECOVERY is only allowd after: | |
2286 | * | |
2287 | * (1) UB_STATE_OPEN is not set, which means the dying process is exited | |
2288 | * and related io_uring ctx is freed so file struct of /dev/ublkcX is | |
2289 | * released. | |
2290 | * | |
2291 | * (2) UBLK_S_DEV_QUIESCED is set, which means the quiesce_work: | |
2292 | * (a)has quiesced request queue | |
2293 | * (b)has requeued every inflight rqs whose io_flags is ACTIVE | |
2294 | * (c)has requeued/aborted every inflight rqs whose io_flags is NOT ACTIVE | |
2295 | * (d)has completed/camceled all ioucmds owned by ther dying process | |
2296 | */ | |
2297 | if (test_bit(UB_STATE_OPEN, &ub->state) || | |
2298 | ub->dev_info.state != UBLK_S_DEV_QUIESCED) { | |
2299 | ret = -EBUSY; | |
2300 | goto out_unlock; | |
2301 | } | |
2302 | pr_devel("%s: start recovery for dev id %d.\n", __func__, header->dev_id); | |
2303 | for (i = 0; i < ub->dev_info.nr_hw_queues; i++) | |
2304 | ublk_queue_reinit(ub, ublk_get_queue(ub, i)); | |
2305 | /* set to NULL, otherwise new ubq_daemon cannot mmap the io_cmd_buf */ | |
2306 | ub->mm = NULL; | |
2307 | ub->nr_queues_ready = 0; | |
73a166d9 | 2308 | ub->nr_privileged_daemon = 0; |
c732a852 Z |
2309 | init_completion(&ub->completion); |
2310 | ret = 0; | |
2311 | out_unlock: | |
2312 | mutex_unlock(&ub->mutex); | |
c732a852 Z |
2313 | return ret; |
2314 | } | |
2315 | ||
bfbcef03 ML |
2316 | static int ublk_ctrl_end_recovery(struct ublk_device *ub, |
2317 | struct io_uring_cmd *cmd) | |
c732a852 | 2318 | { |
fd9b8547 | 2319 | const struct ublksrv_ctrl_cmd *header = io_uring_sqe_cmd(cmd->sqe); |
c732a852 | 2320 | int ublksrv_pid = (int)header->data[0]; |
c732a852 Z |
2321 | int ret = -EINVAL; |
2322 | ||
c732a852 Z |
2323 | pr_devel("%s: Waiting for new ubq_daemons(nr: %d) are ready, dev id %d...\n", |
2324 | __func__, ub->dev_info.nr_hw_queues, header->dev_id); | |
2325 | /* wait until new ubq_daemon sending all FETCH_REQ */ | |
2326 | wait_for_completion_interruptible(&ub->completion); | |
2327 | pr_devel("%s: All new ubq_daemons(nr: %d) are ready, dev id %d\n", | |
2328 | __func__, ub->dev_info.nr_hw_queues, header->dev_id); | |
2329 | ||
2330 | mutex_lock(&ub->mutex); | |
2331 | if (!ublk_can_use_recovery(ub)) | |
2332 | goto out_unlock; | |
2333 | ||
2334 | if (ub->dev_info.state != UBLK_S_DEV_QUIESCED) { | |
2335 | ret = -EBUSY; | |
2336 | goto out_unlock; | |
2337 | } | |
2338 | ub->dev_info.ublksrv_pid = ublksrv_pid; | |
2339 | pr_devel("%s: new ublksrv_pid %d, dev id %d\n", | |
2340 | __func__, ublksrv_pid, header->dev_id); | |
2341 | blk_mq_unquiesce_queue(ub->ub_disk->queue); | |
2342 | pr_devel("%s: queue unquiesced, dev id %d.\n", | |
2343 | __func__, header->dev_id); | |
2344 | blk_mq_kick_requeue_list(ub->ub_disk->queue); | |
2345 | ub->dev_info.state = UBLK_S_DEV_LIVE; | |
2346 | schedule_delayed_work(&ub->monitor_work, UBLK_DAEMON_MONITOR_PERIOD); | |
2347 | ret = 0; | |
2348 | out_unlock: | |
2349 | mutex_unlock(&ub->mutex); | |
c732a852 Z |
2350 | return ret; |
2351 | } | |
2352 | ||
b5bbc52f ML |
2353 | static int ublk_ctrl_get_features(struct io_uring_cmd *cmd) |
2354 | { | |
2355 | const struct ublksrv_ctrl_cmd *header = io_uring_sqe_cmd(cmd->sqe); | |
2356 | void __user *argp = (void __user *)(unsigned long)header->addr; | |
2357 | u64 features = UBLK_F_ALL & ~UBLK_F_SUPPORT_ZERO_COPY; | |
2358 | ||
2359 | if (header->len != UBLK_FEATURES_LEN || !header->addr) | |
2360 | return -EINVAL; | |
2361 | ||
2362 | if (copy_to_user(argp, &features, UBLK_FEATURES_LEN)) | |
2363 | return -EFAULT; | |
2364 | ||
2365 | return 0; | |
2366 | } | |
2367 | ||
4093cb5a ML |
2368 | /* |
2369 | * All control commands are sent via /dev/ublk-control, so we have to check | |
2370 | * the destination device's permission | |
2371 | */ | |
2372 | static int ublk_char_dev_permission(struct ublk_device *ub, | |
2373 | const char *dev_path, int mask) | |
2374 | { | |
2375 | int err; | |
2376 | struct path path; | |
2377 | struct kstat stat; | |
2378 | ||
2379 | err = kern_path(dev_path, LOOKUP_FOLLOW, &path); | |
2380 | if (err) | |
2381 | return err; | |
2382 | ||
2383 | err = vfs_getattr(&path, &stat, STATX_TYPE, AT_STATX_SYNC_AS_STAT); | |
2384 | if (err) | |
2385 | goto exit; | |
2386 | ||
2387 | err = -EPERM; | |
2388 | if (stat.rdev != ub->cdev_dev.devt || !S_ISCHR(stat.mode)) | |
2389 | goto exit; | |
2390 | ||
5b0ed596 | 2391 | err = inode_permission(&nop_mnt_idmap, |
4093cb5a ML |
2392 | d_backing_inode(path.dentry), mask); |
2393 | exit: | |
2394 | path_put(&path); | |
2395 | return err; | |
2396 | } | |
2397 | ||
2398 | static int ublk_ctrl_uring_cmd_permission(struct ublk_device *ub, | |
2399 | struct io_uring_cmd *cmd) | |
2400 | { | |
fd9b8547 | 2401 | struct ublksrv_ctrl_cmd *header = (struct ublksrv_ctrl_cmd *)io_uring_sqe_cmd(cmd->sqe); |
4093cb5a ML |
2402 | bool unprivileged = ub->dev_info.flags & UBLK_F_UNPRIVILEGED_DEV; |
2403 | void __user *argp = (void __user *)(unsigned long)header->addr; | |
2404 | char *dev_path = NULL; | |
2405 | int ret = 0; | |
2406 | int mask; | |
2407 | ||
2408 | if (!unprivileged) { | |
2409 | if (!capable(CAP_SYS_ADMIN)) | |
2410 | return -EPERM; | |
2411 | /* | |
2412 | * The new added command of UBLK_CMD_GET_DEV_INFO2 includes | |
2413 | * char_dev_path in payload too, since userspace may not | |
2414 | * know if the specified device is created as unprivileged | |
2415 | * mode. | |
2416 | */ | |
2d786e66 | 2417 | if (_IOC_NR(cmd->cmd_op) != UBLK_CMD_GET_DEV_INFO2) |
4093cb5a ML |
2418 | return 0; |
2419 | } | |
2420 | ||
2421 | /* | |
2422 | * User has to provide the char device path for unprivileged ublk | |
2423 | * | |
2424 | * header->addr always points to the dev path buffer, and | |
2425 | * header->dev_path_len records length of dev path buffer. | |
2426 | */ | |
2427 | if (!header->dev_path_len || header->dev_path_len > PATH_MAX) | |
2428 | return -EINVAL; | |
2429 | ||
2430 | if (header->len < header->dev_path_len) | |
2431 | return -EINVAL; | |
2432 | ||
2433 | dev_path = kmalloc(header->dev_path_len + 1, GFP_KERNEL); | |
2434 | if (!dev_path) | |
2435 | return -ENOMEM; | |
2436 | ||
2437 | ret = -EFAULT; | |
2438 | if (copy_from_user(dev_path, argp, header->dev_path_len)) | |
2439 | goto exit; | |
2440 | dev_path[header->dev_path_len] = 0; | |
2441 | ||
2442 | ret = -EINVAL; | |
2d786e66 | 2443 | switch (_IOC_NR(cmd->cmd_op)) { |
4093cb5a ML |
2444 | case UBLK_CMD_GET_DEV_INFO: |
2445 | case UBLK_CMD_GET_DEV_INFO2: | |
2446 | case UBLK_CMD_GET_QUEUE_AFFINITY: | |
2447 | case UBLK_CMD_GET_PARAMS: | |
b5bbc52f | 2448 | case (_IOC_NR(UBLK_U_CMD_GET_FEATURES)): |
4093cb5a ML |
2449 | mask = MAY_READ; |
2450 | break; | |
2451 | case UBLK_CMD_START_DEV: | |
2452 | case UBLK_CMD_STOP_DEV: | |
2453 | case UBLK_CMD_ADD_DEV: | |
2454 | case UBLK_CMD_DEL_DEV: | |
2455 | case UBLK_CMD_SET_PARAMS: | |
2456 | case UBLK_CMD_START_USER_RECOVERY: | |
2457 | case UBLK_CMD_END_USER_RECOVERY: | |
2458 | mask = MAY_READ | MAY_WRITE; | |
2459 | break; | |
2460 | default: | |
2461 | goto exit; | |
2462 | } | |
2463 | ||
2464 | ret = ublk_char_dev_permission(ub, dev_path, mask); | |
2465 | if (!ret) { | |
2466 | header->len -= header->dev_path_len; | |
2467 | header->addr += header->dev_path_len; | |
2468 | } | |
2469 | pr_devel("%s: dev id %d cmd_op %x uid %d gid %d path %s ret %d\n", | |
2470 | __func__, ub->ub_number, cmd->cmd_op, | |
2471 | ub->dev_info.owner_uid, ub->dev_info.owner_gid, | |
2472 | dev_path, ret); | |
2473 | exit: | |
2474 | kfree(dev_path); | |
c732a852 Z |
2475 | return ret; |
2476 | } | |
2477 | ||
34d8f2be CH |
2478 | static int ublk_ctrl_uring_cmd(struct io_uring_cmd *cmd, |
2479 | unsigned int issue_flags) | |
2480 | { | |
fd9b8547 | 2481 | const struct ublksrv_ctrl_cmd *header = io_uring_sqe_cmd(cmd->sqe); |
bfbcef03 | 2482 | struct ublk_device *ub = NULL; |
2d786e66 | 2483 | u32 cmd_op = cmd->cmd_op; |
71f28f31 ML |
2484 | int ret = -EINVAL; |
2485 | ||
fa8e442e ML |
2486 | if (issue_flags & IO_URING_F_NONBLOCK) |
2487 | return -EAGAIN; | |
2488 | ||
71f28f31 ML |
2489 | ublk_ctrl_cmd_dump(cmd); |
2490 | ||
2491 | if (!(issue_flags & IO_URING_F_SQE128)) | |
2492 | goto out; | |
2493 | ||
2d786e66 ML |
2494 | ret = ublk_check_cmd_op(cmd_op); |
2495 | if (ret) | |
2496 | goto out; | |
2497 | ||
b5bbc52f ML |
2498 | if (cmd_op == UBLK_U_CMD_GET_FEATURES) { |
2499 | ret = ublk_ctrl_get_features(cmd); | |
2500 | goto out; | |
2501 | } | |
2502 | ||
2d786e66 | 2503 | if (_IOC_NR(cmd_op) != UBLK_CMD_ADD_DEV) { |
bfbcef03 ML |
2504 | ret = -ENODEV; |
2505 | ub = ublk_get_device_from_id(header->dev_id); | |
2506 | if (!ub) | |
2507 | goto out; | |
4093cb5a ML |
2508 | |
2509 | ret = ublk_ctrl_uring_cmd_permission(ub, cmd); | |
2d786e66 ML |
2510 | if (ret) |
2511 | goto put_dev; | |
bfbcef03 ML |
2512 | } |
2513 | ||
2d786e66 | 2514 | switch (_IOC_NR(cmd_op)) { |
71f28f31 | 2515 | case UBLK_CMD_START_DEV: |
bfbcef03 | 2516 | ret = ublk_ctrl_start_dev(ub, cmd); |
71f28f31 ML |
2517 | break; |
2518 | case UBLK_CMD_STOP_DEV: | |
bfbcef03 | 2519 | ret = ublk_ctrl_stop_dev(ub); |
71f28f31 ML |
2520 | break; |
2521 | case UBLK_CMD_GET_DEV_INFO: | |
4093cb5a | 2522 | case UBLK_CMD_GET_DEV_INFO2: |
bfbcef03 | 2523 | ret = ublk_ctrl_get_dev_info(ub, cmd); |
71f28f31 ML |
2524 | break; |
2525 | case UBLK_CMD_ADD_DEV: | |
34d8f2be | 2526 | ret = ublk_ctrl_add_dev(cmd); |
71f28f31 ML |
2527 | break; |
2528 | case UBLK_CMD_DEL_DEV: | |
bfbcef03 | 2529 | ret = ublk_ctrl_del_dev(&ub); |
71f28f31 ML |
2530 | break; |
2531 | case UBLK_CMD_GET_QUEUE_AFFINITY: | |
bfbcef03 | 2532 | ret = ublk_ctrl_get_queue_affinity(ub, cmd); |
71f28f31 | 2533 | break; |
0aa73170 | 2534 | case UBLK_CMD_GET_PARAMS: |
bfbcef03 | 2535 | ret = ublk_ctrl_get_params(ub, cmd); |
0aa73170 ML |
2536 | break; |
2537 | case UBLK_CMD_SET_PARAMS: | |
bfbcef03 | 2538 | ret = ublk_ctrl_set_params(ub, cmd); |
0aa73170 | 2539 | break; |
c732a852 | 2540 | case UBLK_CMD_START_USER_RECOVERY: |
bfbcef03 | 2541 | ret = ublk_ctrl_start_recovery(ub, cmd); |
c732a852 Z |
2542 | break; |
2543 | case UBLK_CMD_END_USER_RECOVERY: | |
bfbcef03 | 2544 | ret = ublk_ctrl_end_recovery(ub, cmd); |
c732a852 | 2545 | break; |
71f28f31 | 2546 | default: |
bfbcef03 | 2547 | ret = -ENOTSUPP; |
71f28f31 | 2548 | break; |
6b1439d2 | 2549 | } |
4093cb5a ML |
2550 | |
2551 | put_dev: | |
bfbcef03 ML |
2552 | if (ub) |
2553 | ublk_put_device(ub); | |
71f28f31 | 2554 | out: |
9d2789ac | 2555 | io_uring_cmd_done(cmd, ret, 0, issue_flags); |
71f28f31 ML |
2556 | pr_devel("%s: cmd done ret %d cmd_op %x, dev id %d qid %d\n", |
2557 | __func__, ret, cmd->cmd_op, header->dev_id, header->queue_id); | |
2558 | return -EIOCBQUEUED; | |
2559 | } | |
2560 | ||
2561 | static const struct file_operations ublk_ctl_fops = { | |
2562 | .open = nonseekable_open, | |
2563 | .uring_cmd = ublk_ctrl_uring_cmd, | |
2564 | .owner = THIS_MODULE, | |
2565 | .llseek = noop_llseek, | |
2566 | }; | |
2567 | ||
2568 | static struct miscdevice ublk_misc = { | |
2569 | .minor = MISC_DYNAMIC_MINOR, | |
2570 | .name = "ublk-control", | |
2571 | .fops = &ublk_ctl_fops, | |
2572 | }; | |
2573 | ||
2574 | static int __init ublk_init(void) | |
2575 | { | |
2576 | int ret; | |
2577 | ||
62fe99ce ML |
2578 | BUILD_BUG_ON((u64)UBLKSRV_IO_BUF_OFFSET + |
2579 | UBLKSRV_IO_BUF_TOTAL_SIZE < UBLKSRV_IO_BUF_OFFSET); | |
2580 | ||
71f28f31 ML |
2581 | init_waitqueue_head(&ublk_idr_wq); |
2582 | ||
2583 | ret = misc_register(&ublk_misc); | |
2584 | if (ret) | |
2585 | return ret; | |
2586 | ||
2587 | ret = alloc_chrdev_region(&ublk_chr_devt, 0, UBLK_MINORS, "ublk-char"); | |
2588 | if (ret) | |
2589 | goto unregister_mis; | |
2590 | ||
2eefd399 IO |
2591 | ret = class_register(&ublk_chr_class); |
2592 | if (ret) | |
71f28f31 | 2593 | goto free_chrdev_region; |
2eefd399 | 2594 | |
71f28f31 ML |
2595 | return 0; |
2596 | ||
2597 | free_chrdev_region: | |
2598 | unregister_chrdev_region(ublk_chr_devt, UBLK_MINORS); | |
2599 | unregister_mis: | |
2600 | misc_deregister(&ublk_misc); | |
2601 | return ret; | |
2602 | } | |
2603 | ||
2604 | static void __exit ublk_exit(void) | |
2605 | { | |
2606 | struct ublk_device *ub; | |
2607 | int id; | |
2608 | ||
71f28f31 ML |
2609 | idr_for_each_entry(&ublk_index_idr, ub, id) |
2610 | ublk_remove(ub); | |
2611 | ||
2eefd399 | 2612 | class_unregister(&ublk_chr_class); |
8e4ff684 ML |
2613 | misc_deregister(&ublk_misc); |
2614 | ||
71f28f31 ML |
2615 | idr_destroy(&ublk_index_idr); |
2616 | unregister_chrdev_region(ublk_chr_devt, UBLK_MINORS); | |
2617 | } | |
2618 | ||
2619 | module_init(ublk_init); | |
2620 | module_exit(ublk_exit); | |
2621 | ||
403ebc87 ML |
2622 | module_param(ublks_max, int, 0444); |
2623 | MODULE_PARM_DESC(ublks_max, "max number of ublk devices allowed to add(default: 64)"); | |
2624 | ||
71f28f31 ML |
2625 | MODULE_AUTHOR("Ming Lei <ming.lei@redhat.com>"); |
2626 | MODULE_LICENSE("GPL"); |