xref: /openbmc/linux/drivers/nvme/host/ioctl.c (revision b868a02e)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2011-2014, Intel Corporation.
4  * Copyright (c) 2017-2021 Christoph Hellwig.
5  */
6 #include <linux/ptrace.h>	/* for force_successful_syscall_return */
7 #include <linux/nvme_ioctl.h>
8 #include <linux/io_uring.h>
9 #include "nvme.h"
10 
11 /*
12  * Convert integer values from ioctl structures to user pointers, silently
13  * ignoring the upper bits in the compat case to match behaviour of 32-bit
14  * kernels.
15  */
16 static void __user *nvme_to_user_ptr(uintptr_t ptrval)
17 {
18 	if (in_compat_syscall())
19 		ptrval = (compat_uptr_t)ptrval;
20 	return (void __user *)ptrval;
21 }
22 
23 static void *nvme_add_user_metadata(struct request *req, void __user *ubuf,
24 		unsigned len, u32 seed)
25 {
26 	struct bio_integrity_payload *bip;
27 	int ret = -ENOMEM;
28 	void *buf;
29 	struct bio *bio = req->bio;
30 
31 	buf = kmalloc(len, GFP_KERNEL);
32 	if (!buf)
33 		goto out;
34 
35 	ret = -EFAULT;
36 	if ((req_op(req) == REQ_OP_DRV_OUT) && copy_from_user(buf, ubuf, len))
37 		goto out_free_meta;
38 
39 	bip = bio_integrity_alloc(bio, GFP_KERNEL, 1);
40 	if (IS_ERR(bip)) {
41 		ret = PTR_ERR(bip);
42 		goto out_free_meta;
43 	}
44 
45 	bip->bip_iter.bi_size = len;
46 	bip->bip_iter.bi_sector = seed;
47 	ret = bio_integrity_add_page(bio, virt_to_page(buf), len,
48 			offset_in_page(buf));
49 	if (ret != len) {
50 		ret = -ENOMEM;
51 		goto out_free_meta;
52 	}
53 
54 	req->cmd_flags |= REQ_INTEGRITY;
55 	return buf;
56 out_free_meta:
57 	kfree(buf);
58 out:
59 	return ERR_PTR(ret);
60 }
61 
62 static int nvme_finish_user_metadata(struct request *req, void __user *ubuf,
63 		void *meta, unsigned len, int ret)
64 {
65 	if (!ret && req_op(req) == REQ_OP_DRV_IN &&
66 	    copy_to_user(ubuf, meta, len))
67 		ret = -EFAULT;
68 	kfree(meta);
69 	return ret;
70 }
71 
72 static struct request *nvme_alloc_user_request(struct request_queue *q,
73 		struct nvme_command *cmd, blk_opf_t rq_flags,
74 		blk_mq_req_flags_t blk_flags)
75 {
76 	struct request *req;
77 
78 	req = blk_mq_alloc_request(q, nvme_req_op(cmd) | rq_flags, blk_flags);
79 	if (IS_ERR(req))
80 		return req;
81 	nvme_init_request(req, cmd);
82 	nvme_req(req)->flags |= NVME_REQ_USERCMD;
83 	return req;
84 }
85 
86 static int nvme_map_user_request(struct request *req, u64 ubuffer,
87 		unsigned bufflen, void __user *meta_buffer, unsigned meta_len,
88 		u32 meta_seed, void **metap, struct io_uring_cmd *ioucmd,
89 		bool vec)
90 {
91 	struct request_queue *q = req->q;
92 	struct nvme_ns *ns = q->queuedata;
93 	struct block_device *bdev = ns ? ns->disk->part0 : NULL;
94 	struct bio *bio = NULL;
95 	void *meta = NULL;
96 	int ret;
97 
98 	if (ioucmd && (ioucmd->flags & IORING_URING_CMD_FIXED)) {
99 		struct iov_iter iter;
100 
101 		/* fixedbufs is only for non-vectored io */
102 		if (WARN_ON_ONCE(vec))
103 			return -EINVAL;
104 		ret = io_uring_cmd_import_fixed(ubuffer, bufflen,
105 				rq_data_dir(req), &iter, ioucmd);
106 		if (ret < 0)
107 			goto out;
108 		ret = blk_rq_map_user_iov(q, req, NULL, &iter, GFP_KERNEL);
109 	} else {
110 		ret = blk_rq_map_user_io(req, NULL, nvme_to_user_ptr(ubuffer),
111 				bufflen, GFP_KERNEL, vec, 0, 0,
112 				rq_data_dir(req));
113 	}
114 
115 	if (ret)
116 		goto out;
117 	bio = req->bio;
118 	if (bdev)
119 		bio_set_dev(bio, bdev);
120 
121 	if (bdev && meta_buffer && meta_len) {
122 		meta = nvme_add_user_metadata(req, meta_buffer, meta_len,
123 				meta_seed);
124 		if (IS_ERR(meta)) {
125 			ret = PTR_ERR(meta);
126 			goto out_unmap;
127 		}
128 		*metap = meta;
129 	}
130 
131 	return ret;
132 
133 out_unmap:
134 	if (bio)
135 		blk_rq_unmap_user(bio);
136 out:
137 	blk_mq_free_request(req);
138 	return ret;
139 }
140 
141 static int nvme_submit_user_cmd(struct request_queue *q,
142 		struct nvme_command *cmd, u64 ubuffer,
143 		unsigned bufflen, void __user *meta_buffer, unsigned meta_len,
144 		u32 meta_seed, u64 *result, unsigned timeout, bool vec)
145 {
146 	struct nvme_ctrl *ctrl;
147 	struct request *req;
148 	void *meta = NULL;
149 	struct bio *bio;
150 	u32 effects;
151 	int ret;
152 
153 	req = nvme_alloc_user_request(q, cmd, 0, 0);
154 	if (IS_ERR(req))
155 		return PTR_ERR(req);
156 
157 	req->timeout = timeout;
158 	if (ubuffer && bufflen) {
159 		ret = nvme_map_user_request(req, ubuffer, bufflen, meta_buffer,
160 				meta_len, meta_seed, &meta, NULL, vec);
161 		if (ret)
162 			return ret;
163 	}
164 
165 	bio = req->bio;
166 	ctrl = nvme_req(req)->ctrl;
167 
168 	ret = nvme_execute_passthru_rq(req, &effects);
169 
170 	if (result)
171 		*result = le64_to_cpu(nvme_req(req)->result.u64);
172 	if (meta)
173 		ret = nvme_finish_user_metadata(req, meta_buffer, meta,
174 						meta_len, ret);
175 	if (bio)
176 		blk_rq_unmap_user(bio);
177 	blk_mq_free_request(req);
178 
179 	if (effects)
180 		nvme_passthru_end(ctrl, effects, cmd, ret);
181 
182 	return ret;
183 }
184 
185 static int nvme_submit_io(struct nvme_ns *ns, struct nvme_user_io __user *uio)
186 {
187 	struct nvme_user_io io;
188 	struct nvme_command c;
189 	unsigned length, meta_len;
190 	void __user *metadata;
191 
192 	if (copy_from_user(&io, uio, sizeof(io)))
193 		return -EFAULT;
194 	if (io.flags)
195 		return -EINVAL;
196 
197 	switch (io.opcode) {
198 	case nvme_cmd_write:
199 	case nvme_cmd_read:
200 	case nvme_cmd_compare:
201 		break;
202 	default:
203 		return -EINVAL;
204 	}
205 
206 	length = (io.nblocks + 1) << ns->lba_shift;
207 
208 	if ((io.control & NVME_RW_PRINFO_PRACT) &&
209 	    ns->ms == sizeof(struct t10_pi_tuple)) {
210 		/*
211 		 * Protection information is stripped/inserted by the
212 		 * controller.
213 		 */
214 		if (nvme_to_user_ptr(io.metadata))
215 			return -EINVAL;
216 		meta_len = 0;
217 		metadata = NULL;
218 	} else {
219 		meta_len = (io.nblocks + 1) * ns->ms;
220 		metadata = nvme_to_user_ptr(io.metadata);
221 	}
222 
223 	if (ns->features & NVME_NS_EXT_LBAS) {
224 		length += meta_len;
225 		meta_len = 0;
226 	} else if (meta_len) {
227 		if ((io.metadata & 3) || !io.metadata)
228 			return -EINVAL;
229 	}
230 
231 	memset(&c, 0, sizeof(c));
232 	c.rw.opcode = io.opcode;
233 	c.rw.flags = io.flags;
234 	c.rw.nsid = cpu_to_le32(ns->head->ns_id);
235 	c.rw.slba = cpu_to_le64(io.slba);
236 	c.rw.length = cpu_to_le16(io.nblocks);
237 	c.rw.control = cpu_to_le16(io.control);
238 	c.rw.dsmgmt = cpu_to_le32(io.dsmgmt);
239 	c.rw.reftag = cpu_to_le32(io.reftag);
240 	c.rw.apptag = cpu_to_le16(io.apptag);
241 	c.rw.appmask = cpu_to_le16(io.appmask);
242 
243 	return nvme_submit_user_cmd(ns->queue, &c,
244 			io.addr, length,
245 			metadata, meta_len, lower_32_bits(io.slba), NULL, 0,
246 			false);
247 }
248 
249 static bool nvme_validate_passthru_nsid(struct nvme_ctrl *ctrl,
250 					struct nvme_ns *ns, __u32 nsid)
251 {
252 	if (ns && nsid != ns->head->ns_id) {
253 		dev_err(ctrl->device,
254 			"%s: nsid (%u) in cmd does not match nsid (%u)"
255 			"of namespace\n",
256 			current->comm, nsid, ns->head->ns_id);
257 		return false;
258 	}
259 
260 	return true;
261 }
262 
263 static int nvme_user_cmd(struct nvme_ctrl *ctrl, struct nvme_ns *ns,
264 			struct nvme_passthru_cmd __user *ucmd)
265 {
266 	struct nvme_passthru_cmd cmd;
267 	struct nvme_command c;
268 	unsigned timeout = 0;
269 	u64 result;
270 	int status;
271 
272 	if (!capable(CAP_SYS_ADMIN))
273 		return -EACCES;
274 	if (copy_from_user(&cmd, ucmd, sizeof(cmd)))
275 		return -EFAULT;
276 	if (cmd.flags)
277 		return -EINVAL;
278 	if (!nvme_validate_passthru_nsid(ctrl, ns, cmd.nsid))
279 		return -EINVAL;
280 
281 	memset(&c, 0, sizeof(c));
282 	c.common.opcode = cmd.opcode;
283 	c.common.flags = cmd.flags;
284 	c.common.nsid = cpu_to_le32(cmd.nsid);
285 	c.common.cdw2[0] = cpu_to_le32(cmd.cdw2);
286 	c.common.cdw2[1] = cpu_to_le32(cmd.cdw3);
287 	c.common.cdw10 = cpu_to_le32(cmd.cdw10);
288 	c.common.cdw11 = cpu_to_le32(cmd.cdw11);
289 	c.common.cdw12 = cpu_to_le32(cmd.cdw12);
290 	c.common.cdw13 = cpu_to_le32(cmd.cdw13);
291 	c.common.cdw14 = cpu_to_le32(cmd.cdw14);
292 	c.common.cdw15 = cpu_to_le32(cmd.cdw15);
293 
294 	if (cmd.timeout_ms)
295 		timeout = msecs_to_jiffies(cmd.timeout_ms);
296 
297 	status = nvme_submit_user_cmd(ns ? ns->queue : ctrl->admin_q, &c,
298 			cmd.addr, cmd.data_len,
299 			nvme_to_user_ptr(cmd.metadata), cmd.metadata_len,
300 			0, &result, timeout, false);
301 
302 	if (status >= 0) {
303 		if (put_user(result, &ucmd->result))
304 			return -EFAULT;
305 	}
306 
307 	return status;
308 }
309 
310 static int nvme_user_cmd64(struct nvme_ctrl *ctrl, struct nvme_ns *ns,
311 			struct nvme_passthru_cmd64 __user *ucmd, bool vec)
312 {
313 	struct nvme_passthru_cmd64 cmd;
314 	struct nvme_command c;
315 	unsigned timeout = 0;
316 	int status;
317 
318 	if (!capable(CAP_SYS_ADMIN))
319 		return -EACCES;
320 	if (copy_from_user(&cmd, ucmd, sizeof(cmd)))
321 		return -EFAULT;
322 	if (cmd.flags)
323 		return -EINVAL;
324 	if (!nvme_validate_passthru_nsid(ctrl, ns, cmd.nsid))
325 		return -EINVAL;
326 
327 	memset(&c, 0, sizeof(c));
328 	c.common.opcode = cmd.opcode;
329 	c.common.flags = cmd.flags;
330 	c.common.nsid = cpu_to_le32(cmd.nsid);
331 	c.common.cdw2[0] = cpu_to_le32(cmd.cdw2);
332 	c.common.cdw2[1] = cpu_to_le32(cmd.cdw3);
333 	c.common.cdw10 = cpu_to_le32(cmd.cdw10);
334 	c.common.cdw11 = cpu_to_le32(cmd.cdw11);
335 	c.common.cdw12 = cpu_to_le32(cmd.cdw12);
336 	c.common.cdw13 = cpu_to_le32(cmd.cdw13);
337 	c.common.cdw14 = cpu_to_le32(cmd.cdw14);
338 	c.common.cdw15 = cpu_to_le32(cmd.cdw15);
339 
340 	if (cmd.timeout_ms)
341 		timeout = msecs_to_jiffies(cmd.timeout_ms);
342 
343 	status = nvme_submit_user_cmd(ns ? ns->queue : ctrl->admin_q, &c,
344 			cmd.addr, cmd.data_len,
345 			nvme_to_user_ptr(cmd.metadata), cmd.metadata_len,
346 			0, &cmd.result, timeout, vec);
347 
348 	if (status >= 0) {
349 		if (put_user(cmd.result, &ucmd->result))
350 			return -EFAULT;
351 	}
352 
353 	return status;
354 }
355 
356 struct nvme_uring_data {
357 	__u64	metadata;
358 	__u64	addr;
359 	__u32	data_len;
360 	__u32	metadata_len;
361 	__u32	timeout_ms;
362 };
363 
364 /*
365  * This overlays struct io_uring_cmd pdu.
366  * Expect build errors if this grows larger than that.
367  */
368 struct nvme_uring_cmd_pdu {
369 	union {
370 		struct bio *bio;
371 		struct request *req;
372 	};
373 	u32 meta_len;
374 	u32 nvme_status;
375 	union {
376 		struct {
377 			void *meta; /* kernel-resident buffer */
378 			void __user *meta_buffer;
379 		};
380 		u64 result;
381 	} u;
382 };
383 
384 static inline struct nvme_uring_cmd_pdu *nvme_uring_cmd_pdu(
385 		struct io_uring_cmd *ioucmd)
386 {
387 	return (struct nvme_uring_cmd_pdu *)&ioucmd->pdu;
388 }
389 
390 static void nvme_uring_task_meta_cb(struct io_uring_cmd *ioucmd)
391 {
392 	struct nvme_uring_cmd_pdu *pdu = nvme_uring_cmd_pdu(ioucmd);
393 	struct request *req = pdu->req;
394 	int status;
395 	u64 result;
396 
397 	if (nvme_req(req)->flags & NVME_REQ_CANCELLED)
398 		status = -EINTR;
399 	else
400 		status = nvme_req(req)->status;
401 
402 	result = le64_to_cpu(nvme_req(req)->result.u64);
403 
404 	if (pdu->meta_len)
405 		status = nvme_finish_user_metadata(req, pdu->u.meta_buffer,
406 					pdu->u.meta, pdu->meta_len, status);
407 	if (req->bio)
408 		blk_rq_unmap_user(req->bio);
409 	blk_mq_free_request(req);
410 
411 	io_uring_cmd_done(ioucmd, status, result);
412 }
413 
414 static void nvme_uring_task_cb(struct io_uring_cmd *ioucmd)
415 {
416 	struct nvme_uring_cmd_pdu *pdu = nvme_uring_cmd_pdu(ioucmd);
417 
418 	if (pdu->bio)
419 		blk_rq_unmap_user(pdu->bio);
420 
421 	io_uring_cmd_done(ioucmd, pdu->nvme_status, pdu->u.result);
422 }
423 
424 static enum rq_end_io_ret nvme_uring_cmd_end_io(struct request *req,
425 						blk_status_t err)
426 {
427 	struct io_uring_cmd *ioucmd = req->end_io_data;
428 	struct nvme_uring_cmd_pdu *pdu = nvme_uring_cmd_pdu(ioucmd);
429 	void *cookie = READ_ONCE(ioucmd->cookie);
430 
431 	req->bio = pdu->bio;
432 	if (nvme_req(req)->flags & NVME_REQ_CANCELLED)
433 		pdu->nvme_status = -EINTR;
434 	else
435 		pdu->nvme_status = nvme_req(req)->status;
436 	pdu->u.result = le64_to_cpu(nvme_req(req)->result.u64);
437 
438 	/*
439 	 * For iopoll, complete it directly.
440 	 * Otherwise, move the completion to task work.
441 	 */
442 	if (cookie != NULL && blk_rq_is_poll(req))
443 		nvme_uring_task_cb(ioucmd);
444 	else
445 		io_uring_cmd_complete_in_task(ioucmd, nvme_uring_task_cb);
446 
447 	return RQ_END_IO_FREE;
448 }
449 
450 static enum rq_end_io_ret nvme_uring_cmd_end_io_meta(struct request *req,
451 						     blk_status_t err)
452 {
453 	struct io_uring_cmd *ioucmd = req->end_io_data;
454 	struct nvme_uring_cmd_pdu *pdu = nvme_uring_cmd_pdu(ioucmd);
455 	void *cookie = READ_ONCE(ioucmd->cookie);
456 
457 	req->bio = pdu->bio;
458 	pdu->req = req;
459 
460 	/*
461 	 * For iopoll, complete it directly.
462 	 * Otherwise, move the completion to task work.
463 	 */
464 	if (cookie != NULL && blk_rq_is_poll(req))
465 		nvme_uring_task_meta_cb(ioucmd);
466 	else
467 		io_uring_cmd_complete_in_task(ioucmd, nvme_uring_task_meta_cb);
468 
469 	return RQ_END_IO_NONE;
470 }
471 
472 static int nvme_uring_cmd_io(struct nvme_ctrl *ctrl, struct nvme_ns *ns,
473 		struct io_uring_cmd *ioucmd, unsigned int issue_flags, bool vec)
474 {
475 	struct nvme_uring_cmd_pdu *pdu = nvme_uring_cmd_pdu(ioucmd);
476 	const struct nvme_uring_cmd *cmd = ioucmd->cmd;
477 	struct request_queue *q = ns ? ns->queue : ctrl->admin_q;
478 	struct nvme_uring_data d;
479 	struct nvme_command c;
480 	struct request *req;
481 	blk_opf_t rq_flags = 0;
482 	blk_mq_req_flags_t blk_flags = 0;
483 	void *meta = NULL;
484 	int ret;
485 
486 	if (!capable(CAP_SYS_ADMIN))
487 		return -EACCES;
488 
489 	c.common.opcode = READ_ONCE(cmd->opcode);
490 	c.common.flags = READ_ONCE(cmd->flags);
491 	if (c.common.flags)
492 		return -EINVAL;
493 
494 	c.common.command_id = 0;
495 	c.common.nsid = cpu_to_le32(cmd->nsid);
496 	if (!nvme_validate_passthru_nsid(ctrl, ns, le32_to_cpu(c.common.nsid)))
497 		return -EINVAL;
498 
499 	c.common.cdw2[0] = cpu_to_le32(READ_ONCE(cmd->cdw2));
500 	c.common.cdw2[1] = cpu_to_le32(READ_ONCE(cmd->cdw3));
501 	c.common.metadata = 0;
502 	c.common.dptr.prp1 = c.common.dptr.prp2 = 0;
503 	c.common.cdw10 = cpu_to_le32(READ_ONCE(cmd->cdw10));
504 	c.common.cdw11 = cpu_to_le32(READ_ONCE(cmd->cdw11));
505 	c.common.cdw12 = cpu_to_le32(READ_ONCE(cmd->cdw12));
506 	c.common.cdw13 = cpu_to_le32(READ_ONCE(cmd->cdw13));
507 	c.common.cdw14 = cpu_to_le32(READ_ONCE(cmd->cdw14));
508 	c.common.cdw15 = cpu_to_le32(READ_ONCE(cmd->cdw15));
509 
510 	d.metadata = READ_ONCE(cmd->metadata);
511 	d.addr = READ_ONCE(cmd->addr);
512 	d.data_len = READ_ONCE(cmd->data_len);
513 	d.metadata_len = READ_ONCE(cmd->metadata_len);
514 	d.timeout_ms = READ_ONCE(cmd->timeout_ms);
515 
516 	if (issue_flags & IO_URING_F_NONBLOCK) {
517 		rq_flags = REQ_NOWAIT;
518 		blk_flags = BLK_MQ_REQ_NOWAIT;
519 	}
520 	if (issue_flags & IO_URING_F_IOPOLL)
521 		rq_flags |= REQ_POLLED;
522 
523 retry:
524 	req = nvme_alloc_user_request(q, &c, rq_flags, blk_flags);
525 	if (IS_ERR(req))
526 		return PTR_ERR(req);
527 	req->timeout = d.timeout_ms ? msecs_to_jiffies(d.timeout_ms) : 0;
528 
529 	if (d.addr && d.data_len) {
530 		ret = nvme_map_user_request(req, d.addr,
531 			d.data_len, nvme_to_user_ptr(d.metadata),
532 			d.metadata_len, 0, &meta, ioucmd, vec);
533 		if (ret)
534 			return ret;
535 	}
536 
537 	if (issue_flags & IO_URING_F_IOPOLL && rq_flags & REQ_POLLED) {
538 		if (unlikely(!req->bio)) {
539 			/* we can't poll this, so alloc regular req instead */
540 			blk_mq_free_request(req);
541 			rq_flags &= ~REQ_POLLED;
542 			goto retry;
543 		} else {
544 			WRITE_ONCE(ioucmd->cookie, req->bio);
545 			req->bio->bi_opf |= REQ_POLLED;
546 		}
547 	}
548 	/* to free bio on completion, as req->bio will be null at that time */
549 	pdu->bio = req->bio;
550 	pdu->meta_len = d.metadata_len;
551 	req->end_io_data = ioucmd;
552 	if (pdu->meta_len) {
553 		pdu->u.meta = meta;
554 		pdu->u.meta_buffer = nvme_to_user_ptr(d.metadata);
555 		req->end_io = nvme_uring_cmd_end_io_meta;
556 	} else {
557 		req->end_io = nvme_uring_cmd_end_io;
558 	}
559 	blk_execute_rq_nowait(req, false);
560 	return -EIOCBQUEUED;
561 }
562 
563 static bool is_ctrl_ioctl(unsigned int cmd)
564 {
565 	if (cmd == NVME_IOCTL_ADMIN_CMD || cmd == NVME_IOCTL_ADMIN64_CMD)
566 		return true;
567 	if (is_sed_ioctl(cmd))
568 		return true;
569 	return false;
570 }
571 
572 static int nvme_ctrl_ioctl(struct nvme_ctrl *ctrl, unsigned int cmd,
573 		void __user *argp)
574 {
575 	switch (cmd) {
576 	case NVME_IOCTL_ADMIN_CMD:
577 		return nvme_user_cmd(ctrl, NULL, argp);
578 	case NVME_IOCTL_ADMIN64_CMD:
579 		return nvme_user_cmd64(ctrl, NULL, argp, false);
580 	default:
581 		return sed_ioctl(ctrl->opal_dev, cmd, argp);
582 	}
583 }
584 
585 #ifdef COMPAT_FOR_U64_ALIGNMENT
586 struct nvme_user_io32 {
587 	__u8	opcode;
588 	__u8	flags;
589 	__u16	control;
590 	__u16	nblocks;
591 	__u16	rsvd;
592 	__u64	metadata;
593 	__u64	addr;
594 	__u64	slba;
595 	__u32	dsmgmt;
596 	__u32	reftag;
597 	__u16	apptag;
598 	__u16	appmask;
599 } __attribute__((__packed__));
600 #define NVME_IOCTL_SUBMIT_IO32	_IOW('N', 0x42, struct nvme_user_io32)
601 #endif /* COMPAT_FOR_U64_ALIGNMENT */
602 
603 static int nvme_ns_ioctl(struct nvme_ns *ns, unsigned int cmd,
604 		void __user *argp)
605 {
606 	switch (cmd) {
607 	case NVME_IOCTL_ID:
608 		force_successful_syscall_return();
609 		return ns->head->ns_id;
610 	case NVME_IOCTL_IO_CMD:
611 		return nvme_user_cmd(ns->ctrl, ns, argp);
612 	/*
613 	 * struct nvme_user_io can have different padding on some 32-bit ABIs.
614 	 * Just accept the compat version as all fields that are used are the
615 	 * same size and at the same offset.
616 	 */
617 #ifdef COMPAT_FOR_U64_ALIGNMENT
618 	case NVME_IOCTL_SUBMIT_IO32:
619 #endif
620 	case NVME_IOCTL_SUBMIT_IO:
621 		return nvme_submit_io(ns, argp);
622 	case NVME_IOCTL_IO64_CMD:
623 		return nvme_user_cmd64(ns->ctrl, ns, argp, false);
624 	case NVME_IOCTL_IO64_CMD_VEC:
625 		return nvme_user_cmd64(ns->ctrl, ns, argp, true);
626 	default:
627 		return -ENOTTY;
628 	}
629 }
630 
631 static int __nvme_ioctl(struct nvme_ns *ns, unsigned int cmd, void __user *arg)
632 {
633        if (is_ctrl_ioctl(cmd))
634                return nvme_ctrl_ioctl(ns->ctrl, cmd, arg);
635        return nvme_ns_ioctl(ns, cmd, arg);
636 }
637 
638 int nvme_ioctl(struct block_device *bdev, fmode_t mode,
639 		unsigned int cmd, unsigned long arg)
640 {
641 	struct nvme_ns *ns = bdev->bd_disk->private_data;
642 
643 	return __nvme_ioctl(ns, cmd, (void __user *)arg);
644 }
645 
646 long nvme_ns_chr_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
647 {
648 	struct nvme_ns *ns =
649 		container_of(file_inode(file)->i_cdev, struct nvme_ns, cdev);
650 
651 	return __nvme_ioctl(ns, cmd, (void __user *)arg);
652 }
653 
654 static int nvme_uring_cmd_checks(unsigned int issue_flags)
655 {
656 
657 	/* NVMe passthrough requires big SQE/CQE support */
658 	if ((issue_flags & (IO_URING_F_SQE128|IO_URING_F_CQE32)) !=
659 	    (IO_URING_F_SQE128|IO_URING_F_CQE32))
660 		return -EOPNOTSUPP;
661 	return 0;
662 }
663 
664 static int nvme_ns_uring_cmd(struct nvme_ns *ns, struct io_uring_cmd *ioucmd,
665 			     unsigned int issue_flags)
666 {
667 	struct nvme_ctrl *ctrl = ns->ctrl;
668 	int ret;
669 
670 	BUILD_BUG_ON(sizeof(struct nvme_uring_cmd_pdu) > sizeof(ioucmd->pdu));
671 
672 	ret = nvme_uring_cmd_checks(issue_flags);
673 	if (ret)
674 		return ret;
675 
676 	switch (ioucmd->cmd_op) {
677 	case NVME_URING_CMD_IO:
678 		ret = nvme_uring_cmd_io(ctrl, ns, ioucmd, issue_flags, false);
679 		break;
680 	case NVME_URING_CMD_IO_VEC:
681 		ret = nvme_uring_cmd_io(ctrl, ns, ioucmd, issue_flags, true);
682 		break;
683 	default:
684 		ret = -ENOTTY;
685 	}
686 
687 	return ret;
688 }
689 
690 int nvme_ns_chr_uring_cmd(struct io_uring_cmd *ioucmd, unsigned int issue_flags)
691 {
692 	struct nvme_ns *ns = container_of(file_inode(ioucmd->file)->i_cdev,
693 			struct nvme_ns, cdev);
694 
695 	return nvme_ns_uring_cmd(ns, ioucmd, issue_flags);
696 }
697 
698 int nvme_ns_chr_uring_cmd_iopoll(struct io_uring_cmd *ioucmd,
699 				 struct io_comp_batch *iob,
700 				 unsigned int poll_flags)
701 {
702 	struct bio *bio;
703 	int ret = 0;
704 	struct nvme_ns *ns;
705 	struct request_queue *q;
706 
707 	rcu_read_lock();
708 	bio = READ_ONCE(ioucmd->cookie);
709 	ns = container_of(file_inode(ioucmd->file)->i_cdev,
710 			struct nvme_ns, cdev);
711 	q = ns->queue;
712 	if (test_bit(QUEUE_FLAG_POLL, &q->queue_flags) && bio && bio->bi_bdev)
713 		ret = bio_poll(bio, iob, poll_flags);
714 	rcu_read_unlock();
715 	return ret;
716 }
717 #ifdef CONFIG_NVME_MULTIPATH
718 static int nvme_ns_head_ctrl_ioctl(struct nvme_ns *ns, unsigned int cmd,
719 		void __user *argp, struct nvme_ns_head *head, int srcu_idx)
720 	__releases(&head->srcu)
721 {
722 	struct nvme_ctrl *ctrl = ns->ctrl;
723 	int ret;
724 
725 	nvme_get_ctrl(ns->ctrl);
726 	srcu_read_unlock(&head->srcu, srcu_idx);
727 	ret = nvme_ctrl_ioctl(ns->ctrl, cmd, argp);
728 
729 	nvme_put_ctrl(ctrl);
730 	return ret;
731 }
732 
733 int nvme_ns_head_ioctl(struct block_device *bdev, fmode_t mode,
734 		unsigned int cmd, unsigned long arg)
735 {
736 	struct nvme_ns_head *head = bdev->bd_disk->private_data;
737 	void __user *argp = (void __user *)arg;
738 	struct nvme_ns *ns;
739 	int srcu_idx, ret = -EWOULDBLOCK;
740 
741 	srcu_idx = srcu_read_lock(&head->srcu);
742 	ns = nvme_find_path(head);
743 	if (!ns)
744 		goto out_unlock;
745 
746 	/*
747 	 * Handle ioctls that apply to the controller instead of the namespace
748 	 * seperately and drop the ns SRCU reference early.  This avoids a
749 	 * deadlock when deleting namespaces using the passthrough interface.
750 	 */
751 	if (is_ctrl_ioctl(cmd))
752 		return nvme_ns_head_ctrl_ioctl(ns, cmd, argp, head, srcu_idx);
753 
754 	ret = nvme_ns_ioctl(ns, cmd, argp);
755 out_unlock:
756 	srcu_read_unlock(&head->srcu, srcu_idx);
757 	return ret;
758 }
759 
760 long nvme_ns_head_chr_ioctl(struct file *file, unsigned int cmd,
761 		unsigned long arg)
762 {
763 	struct cdev *cdev = file_inode(file)->i_cdev;
764 	struct nvme_ns_head *head =
765 		container_of(cdev, struct nvme_ns_head, cdev);
766 	void __user *argp = (void __user *)arg;
767 	struct nvme_ns *ns;
768 	int srcu_idx, ret = -EWOULDBLOCK;
769 
770 	srcu_idx = srcu_read_lock(&head->srcu);
771 	ns = nvme_find_path(head);
772 	if (!ns)
773 		goto out_unlock;
774 
775 	if (is_ctrl_ioctl(cmd))
776 		return nvme_ns_head_ctrl_ioctl(ns, cmd, argp, head, srcu_idx);
777 
778 	ret = nvme_ns_ioctl(ns, cmd, argp);
779 out_unlock:
780 	srcu_read_unlock(&head->srcu, srcu_idx);
781 	return ret;
782 }
783 
784 int nvme_ns_head_chr_uring_cmd(struct io_uring_cmd *ioucmd,
785 		unsigned int issue_flags)
786 {
787 	struct cdev *cdev = file_inode(ioucmd->file)->i_cdev;
788 	struct nvme_ns_head *head = container_of(cdev, struct nvme_ns_head, cdev);
789 	int srcu_idx = srcu_read_lock(&head->srcu);
790 	struct nvme_ns *ns = nvme_find_path(head);
791 	int ret = -EINVAL;
792 
793 	if (ns)
794 		ret = nvme_ns_uring_cmd(ns, ioucmd, issue_flags);
795 	srcu_read_unlock(&head->srcu, srcu_idx);
796 	return ret;
797 }
798 
799 int nvme_ns_head_chr_uring_cmd_iopoll(struct io_uring_cmd *ioucmd,
800 				      struct io_comp_batch *iob,
801 				      unsigned int poll_flags)
802 {
803 	struct cdev *cdev = file_inode(ioucmd->file)->i_cdev;
804 	struct nvme_ns_head *head = container_of(cdev, struct nvme_ns_head, cdev);
805 	int srcu_idx = srcu_read_lock(&head->srcu);
806 	struct nvme_ns *ns = nvme_find_path(head);
807 	struct bio *bio;
808 	int ret = 0;
809 	struct request_queue *q;
810 
811 	if (ns) {
812 		rcu_read_lock();
813 		bio = READ_ONCE(ioucmd->cookie);
814 		q = ns->queue;
815 		if (test_bit(QUEUE_FLAG_POLL, &q->queue_flags) && bio
816 				&& bio->bi_bdev)
817 			ret = bio_poll(bio, iob, poll_flags);
818 		rcu_read_unlock();
819 	}
820 	srcu_read_unlock(&head->srcu, srcu_idx);
821 	return ret;
822 }
823 #endif /* CONFIG_NVME_MULTIPATH */
824 
825 int nvme_dev_uring_cmd(struct io_uring_cmd *ioucmd, unsigned int issue_flags)
826 {
827 	struct nvme_ctrl *ctrl = ioucmd->file->private_data;
828 	int ret;
829 
830 	/* IOPOLL not supported yet */
831 	if (issue_flags & IO_URING_F_IOPOLL)
832 		return -EOPNOTSUPP;
833 
834 	ret = nvme_uring_cmd_checks(issue_flags);
835 	if (ret)
836 		return ret;
837 
838 	switch (ioucmd->cmd_op) {
839 	case NVME_URING_CMD_ADMIN:
840 		ret = nvme_uring_cmd_io(ctrl, NULL, ioucmd, issue_flags, false);
841 		break;
842 	case NVME_URING_CMD_ADMIN_VEC:
843 		ret = nvme_uring_cmd_io(ctrl, NULL, ioucmd, issue_flags, true);
844 		break;
845 	default:
846 		ret = -ENOTTY;
847 	}
848 
849 	return ret;
850 }
851 
852 static int nvme_dev_user_cmd(struct nvme_ctrl *ctrl, void __user *argp)
853 {
854 	struct nvme_ns *ns;
855 	int ret;
856 
857 	down_read(&ctrl->namespaces_rwsem);
858 	if (list_empty(&ctrl->namespaces)) {
859 		ret = -ENOTTY;
860 		goto out_unlock;
861 	}
862 
863 	ns = list_first_entry(&ctrl->namespaces, struct nvme_ns, list);
864 	if (ns != list_last_entry(&ctrl->namespaces, struct nvme_ns, list)) {
865 		dev_warn(ctrl->device,
866 			"NVME_IOCTL_IO_CMD not supported when multiple namespaces present!\n");
867 		ret = -EINVAL;
868 		goto out_unlock;
869 	}
870 
871 	dev_warn(ctrl->device,
872 		"using deprecated NVME_IOCTL_IO_CMD ioctl on the char device!\n");
873 	kref_get(&ns->kref);
874 	up_read(&ctrl->namespaces_rwsem);
875 
876 	ret = nvme_user_cmd(ctrl, ns, argp);
877 	nvme_put_ns(ns);
878 	return ret;
879 
880 out_unlock:
881 	up_read(&ctrl->namespaces_rwsem);
882 	return ret;
883 }
884 
885 long nvme_dev_ioctl(struct file *file, unsigned int cmd,
886 		unsigned long arg)
887 {
888 	struct nvme_ctrl *ctrl = file->private_data;
889 	void __user *argp = (void __user *)arg;
890 
891 	switch (cmd) {
892 	case NVME_IOCTL_ADMIN_CMD:
893 		return nvme_user_cmd(ctrl, NULL, argp);
894 	case NVME_IOCTL_ADMIN64_CMD:
895 		return nvme_user_cmd64(ctrl, NULL, argp, false);
896 	case NVME_IOCTL_IO_CMD:
897 		return nvme_dev_user_cmd(ctrl, argp);
898 	case NVME_IOCTL_RESET:
899 		if (!capable(CAP_SYS_ADMIN))
900 			return -EACCES;
901 		dev_warn(ctrl->device, "resetting controller\n");
902 		return nvme_reset_ctrl_sync(ctrl);
903 	case NVME_IOCTL_SUBSYS_RESET:
904 		if (!capable(CAP_SYS_ADMIN))
905 			return -EACCES;
906 		return nvme_reset_subsystem(ctrl);
907 	case NVME_IOCTL_RESCAN:
908 		if (!capable(CAP_SYS_ADMIN))
909 			return -EACCES;
910 		nvme_queue_scan(ctrl);
911 		return 0;
912 	default:
913 		return -ENOTTY;
914 	}
915 }
916