xref: /linux/drivers/cxl/core/mbox.c (revision 7ec462100ef9142344ddbf86f2c3008b97acddbe)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /* Copyright(c) 2020 Intel Corporation. All rights reserved. */
3 #include <linux/security.h>
4 #include <linux/debugfs.h>
5 #include <linux/ktime.h>
6 #include <linux/mutex.h>
7 #include <linux/unaligned.h>
8 #include <cxlpci.h>
9 #include <cxlmem.h>
10 #include <cxl.h>
11 
12 #include "core.h"
13 #include "trace.h"
14 
15 static bool cxl_raw_allow_all;
16 
17 /**
18  * DOC: cxl mbox
19  *
20  * Core implementation of the CXL 2.0 Type-3 Memory Device Mailbox. The
21  * implementation is used by the cxl_pci driver to initialize the device
22  * and implement the cxl_mem.h IOCTL UAPI. It also implements the
23  * backend of the cxl_pmem_ctl() transport for LIBNVDIMM.
24  */
25 
26 #define cxl_for_each_cmd(cmd)                                                  \
27 	for ((cmd) = &cxl_mem_commands[0];                                     \
28 	     ((cmd) - cxl_mem_commands) < ARRAY_SIZE(cxl_mem_commands); (cmd)++)
29 
30 #define CXL_CMD(_id, sin, sout, _flags)                                        \
31 	[CXL_MEM_COMMAND_ID_##_id] = {                                         \
32 	.info =	{                                                              \
33 			.id = CXL_MEM_COMMAND_ID_##_id,                        \
34 			.size_in = sin,                                        \
35 			.size_out = sout,                                      \
36 		},                                                             \
37 	.opcode = CXL_MBOX_OP_##_id,                                           \
38 	.flags = _flags,                                                       \
39 	}
40 
41 #define CXL_VARIABLE_PAYLOAD	~0U
42 /*
43  * This table defines the supported mailbox commands for the driver. This table
44  * is made up of a UAPI structure. Non-negative values as parameters in the
45  * table will be validated against the user's input. For example, if size_in is
46  * 0, and the user passed in 1, it is an error.
47  */
48 static struct cxl_mem_command cxl_mem_commands[CXL_MEM_COMMAND_ID_MAX] = {
49 	CXL_CMD(IDENTIFY, 0, 0x43, CXL_CMD_FLAG_FORCE_ENABLE),
50 #ifdef CONFIG_CXL_MEM_RAW_COMMANDS
51 	CXL_CMD(RAW, CXL_VARIABLE_PAYLOAD, CXL_VARIABLE_PAYLOAD, 0),
52 #endif
53 	CXL_CMD(GET_SUPPORTED_LOGS, 0, CXL_VARIABLE_PAYLOAD, CXL_CMD_FLAG_FORCE_ENABLE),
54 	CXL_CMD(GET_FW_INFO, 0, 0x50, 0),
55 	CXL_CMD(GET_PARTITION_INFO, 0, 0x20, 0),
56 	CXL_CMD(GET_LSA, 0x8, CXL_VARIABLE_PAYLOAD, 0),
57 	CXL_CMD(GET_HEALTH_INFO, 0, 0x12, 0),
58 	CXL_CMD(GET_LOG, 0x18, CXL_VARIABLE_PAYLOAD, CXL_CMD_FLAG_FORCE_ENABLE),
59 	CXL_CMD(GET_LOG_CAPS, 0x10, 0x4, 0),
60 	CXL_CMD(CLEAR_LOG, 0x10, 0, 0),
61 	CXL_CMD(GET_SUP_LOG_SUBLIST, 0x2, CXL_VARIABLE_PAYLOAD, 0),
62 	CXL_CMD(SET_PARTITION_INFO, 0x0a, 0, 0),
63 	CXL_CMD(SET_LSA, CXL_VARIABLE_PAYLOAD, 0, 0),
64 	CXL_CMD(GET_ALERT_CONFIG, 0, 0x10, 0),
65 	CXL_CMD(SET_ALERT_CONFIG, 0xc, 0, 0),
66 	CXL_CMD(GET_SHUTDOWN_STATE, 0, 0x1, 0),
67 	CXL_CMD(SET_SHUTDOWN_STATE, 0x1, 0, 0),
68 	CXL_CMD(GET_SCAN_MEDIA_CAPS, 0x10, 0x4, 0),
69 	CXL_CMD(GET_TIMESTAMP, 0, 0x8, 0),
70 };
71 
72 /*
73  * Commands that RAW doesn't permit. The rationale for each:
74  *
75  * CXL_MBOX_OP_ACTIVATE_FW: Firmware activation requires adjustment /
76  * coordination of transaction timeout values at the root bridge level.
77  *
78  * CXL_MBOX_OP_SET_PARTITION_INFO: The device memory map may change live
79  * and needs to be coordinated with HDM updates.
80  *
81  * CXL_MBOX_OP_SET_LSA: The label storage area may be cached by the
82  * driver and any writes from userspace invalidates those contents.
83  *
84  * CXL_MBOX_OP_SET_SHUTDOWN_STATE: Set shutdown state assumes no writes
85  * to the device after it is marked clean, userspace can not make that
86  * assertion.
87  *
88  * CXL_MBOX_OP_[GET_]SCAN_MEDIA: The kernel provides a native error list that
89  * is kept up to date with patrol notifications and error management.
90  *
91  * CXL_MBOX_OP_[GET_,INJECT_,CLEAR_]POISON: These commands require kernel
92  * driver orchestration for safety.
93  */
94 static u16 cxl_disabled_raw_commands[] = {
95 	CXL_MBOX_OP_ACTIVATE_FW,
96 	CXL_MBOX_OP_SET_PARTITION_INFO,
97 	CXL_MBOX_OP_SET_LSA,
98 	CXL_MBOX_OP_SET_SHUTDOWN_STATE,
99 	CXL_MBOX_OP_SCAN_MEDIA,
100 	CXL_MBOX_OP_GET_SCAN_MEDIA,
101 	CXL_MBOX_OP_GET_POISON,
102 	CXL_MBOX_OP_INJECT_POISON,
103 	CXL_MBOX_OP_CLEAR_POISON,
104 };
105 
106 /*
107  * Command sets that RAW doesn't permit. All opcodes in this set are
108  * disabled because they pass plain text security payloads over the
109  * user/kernel boundary. This functionality is intended to be wrapped
110  * behind the keys ABI which allows for encrypted payloads in the UAPI
111  */
112 static u8 security_command_sets[] = {
113 	0x44, /* Sanitize */
114 	0x45, /* Persistent Memory Data-at-rest Security */
115 	0x46, /* Security Passthrough */
116 };
117 
cxl_is_security_command(u16 opcode)118 static bool cxl_is_security_command(u16 opcode)
119 {
120 	int i;
121 
122 	for (i = 0; i < ARRAY_SIZE(security_command_sets); i++)
123 		if (security_command_sets[i] == (opcode >> 8))
124 			return true;
125 	return false;
126 }
127 
cxl_set_security_cmd_enabled(struct cxl_security_state * security,u16 opcode)128 static void cxl_set_security_cmd_enabled(struct cxl_security_state *security,
129 					 u16 opcode)
130 {
131 	switch (opcode) {
132 	case CXL_MBOX_OP_SANITIZE:
133 		set_bit(CXL_SEC_ENABLED_SANITIZE, security->enabled_cmds);
134 		break;
135 	case CXL_MBOX_OP_SECURE_ERASE:
136 		set_bit(CXL_SEC_ENABLED_SECURE_ERASE,
137 			security->enabled_cmds);
138 		break;
139 	case CXL_MBOX_OP_GET_SECURITY_STATE:
140 		set_bit(CXL_SEC_ENABLED_GET_SECURITY_STATE,
141 			security->enabled_cmds);
142 		break;
143 	case CXL_MBOX_OP_SET_PASSPHRASE:
144 		set_bit(CXL_SEC_ENABLED_SET_PASSPHRASE,
145 			security->enabled_cmds);
146 		break;
147 	case CXL_MBOX_OP_DISABLE_PASSPHRASE:
148 		set_bit(CXL_SEC_ENABLED_DISABLE_PASSPHRASE,
149 			security->enabled_cmds);
150 		break;
151 	case CXL_MBOX_OP_UNLOCK:
152 		set_bit(CXL_SEC_ENABLED_UNLOCK, security->enabled_cmds);
153 		break;
154 	case CXL_MBOX_OP_FREEZE_SECURITY:
155 		set_bit(CXL_SEC_ENABLED_FREEZE_SECURITY,
156 			security->enabled_cmds);
157 		break;
158 	case CXL_MBOX_OP_PASSPHRASE_SECURE_ERASE:
159 		set_bit(CXL_SEC_ENABLED_PASSPHRASE_SECURE_ERASE,
160 			security->enabled_cmds);
161 		break;
162 	default:
163 		break;
164 	}
165 }
166 
cxl_is_poison_command(u16 opcode)167 static bool cxl_is_poison_command(u16 opcode)
168 {
169 #define CXL_MBOX_OP_POISON_CMDS 0x43
170 
171 	if ((opcode >> 8) == CXL_MBOX_OP_POISON_CMDS)
172 		return true;
173 
174 	return false;
175 }
176 
cxl_set_poison_cmd_enabled(struct cxl_poison_state * poison,u16 opcode)177 static void cxl_set_poison_cmd_enabled(struct cxl_poison_state *poison,
178 				       u16 opcode)
179 {
180 	switch (opcode) {
181 	case CXL_MBOX_OP_GET_POISON:
182 		set_bit(CXL_POISON_ENABLED_LIST, poison->enabled_cmds);
183 		break;
184 	case CXL_MBOX_OP_INJECT_POISON:
185 		set_bit(CXL_POISON_ENABLED_INJECT, poison->enabled_cmds);
186 		break;
187 	case CXL_MBOX_OP_CLEAR_POISON:
188 		set_bit(CXL_POISON_ENABLED_CLEAR, poison->enabled_cmds);
189 		break;
190 	case CXL_MBOX_OP_GET_SCAN_MEDIA_CAPS:
191 		set_bit(CXL_POISON_ENABLED_SCAN_CAPS, poison->enabled_cmds);
192 		break;
193 	case CXL_MBOX_OP_SCAN_MEDIA:
194 		set_bit(CXL_POISON_ENABLED_SCAN_MEDIA, poison->enabled_cmds);
195 		break;
196 	case CXL_MBOX_OP_GET_SCAN_MEDIA:
197 		set_bit(CXL_POISON_ENABLED_SCAN_RESULTS, poison->enabled_cmds);
198 		break;
199 	default:
200 		break;
201 	}
202 }
203 
cxl_mem_find_command(u16 opcode)204 static struct cxl_mem_command *cxl_mem_find_command(u16 opcode)
205 {
206 	struct cxl_mem_command *c;
207 
208 	cxl_for_each_cmd(c)
209 		if (c->opcode == opcode)
210 			return c;
211 
212 	return NULL;
213 }
214 
cxl_mem_opcode_to_name(u16 opcode)215 static const char *cxl_mem_opcode_to_name(u16 opcode)
216 {
217 	struct cxl_mem_command *c;
218 
219 	c = cxl_mem_find_command(opcode);
220 	if (!c)
221 		return NULL;
222 
223 	return cxl_command_names[c->info.id].name;
224 }
225 
226 /**
227  * cxl_internal_send_cmd() - Kernel internal interface to send a mailbox command
228  * @cxl_mbox: CXL mailbox context
229  * @mbox_cmd: initialized command to execute
230  *
231  * Context: Any context.
232  * Return:
233  *  * %>=0	- Number of bytes returned in @out.
234  *  * %-E2BIG	- Payload is too large for hardware.
235  *  * %-EBUSY	- Couldn't acquire exclusive mailbox access.
236  *  * %-EFAULT	- Hardware error occurred.
237  *  * %-ENXIO	- Command completed, but device reported an error.
238  *  * %-EIO	- Unexpected output size.
239  *
240  * Mailbox commands may execute successfully yet the device itself reported an
241  * error. While this distinction can be useful for commands from userspace, the
242  * kernel will only be able to use results when both are successful.
243  */
cxl_internal_send_cmd(struct cxl_mailbox * cxl_mbox,struct cxl_mbox_cmd * mbox_cmd)244 int cxl_internal_send_cmd(struct cxl_mailbox *cxl_mbox,
245 			  struct cxl_mbox_cmd *mbox_cmd)
246 {
247 	size_t out_size, min_out;
248 	int rc;
249 
250 	if (mbox_cmd->size_in > cxl_mbox->payload_size ||
251 	    mbox_cmd->size_out > cxl_mbox->payload_size)
252 		return -E2BIG;
253 
254 	out_size = mbox_cmd->size_out;
255 	min_out = mbox_cmd->min_out;
256 	rc = cxl_mbox->mbox_send(cxl_mbox, mbox_cmd);
257 	/*
258 	 * EIO is reserved for a payload size mismatch and mbox_send()
259 	 * may not return this error.
260 	 */
261 	if (WARN_ONCE(rc == -EIO, "Bad return code: -EIO"))
262 		return -ENXIO;
263 	if (rc)
264 		return rc;
265 
266 	if (mbox_cmd->return_code != CXL_MBOX_CMD_RC_SUCCESS &&
267 	    mbox_cmd->return_code != CXL_MBOX_CMD_RC_BACKGROUND)
268 		return cxl_mbox_cmd_rc2errno(mbox_cmd);
269 
270 	if (!out_size)
271 		return 0;
272 
273 	/*
274 	 * Variable sized output needs to at least satisfy the caller's
275 	 * minimum if not the fully requested size.
276 	 */
277 	if (min_out == 0)
278 		min_out = out_size;
279 
280 	if (mbox_cmd->size_out < min_out)
281 		return -EIO;
282 	return 0;
283 }
284 EXPORT_SYMBOL_NS_GPL(cxl_internal_send_cmd, CXL);
285 
cxl_mem_raw_command_allowed(u16 opcode)286 static bool cxl_mem_raw_command_allowed(u16 opcode)
287 {
288 	int i;
289 
290 	if (!IS_ENABLED(CONFIG_CXL_MEM_RAW_COMMANDS))
291 		return false;
292 
293 	if (security_locked_down(LOCKDOWN_PCI_ACCESS))
294 		return false;
295 
296 	if (cxl_raw_allow_all)
297 		return true;
298 
299 	if (cxl_is_security_command(opcode))
300 		return false;
301 
302 	for (i = 0; i < ARRAY_SIZE(cxl_disabled_raw_commands); i++)
303 		if (cxl_disabled_raw_commands[i] == opcode)
304 			return false;
305 
306 	return true;
307 }
308 
309 /**
310  * cxl_payload_from_user_allowed() - Check contents of in_payload.
311  * @opcode: The mailbox command opcode.
312  * @payload_in: Pointer to the input payload passed in from user space.
313  *
314  * Return:
315  *  * true	- payload_in passes check for @opcode.
316  *  * false	- payload_in contains invalid or unsupported values.
317  *
318  * The driver may inspect payload contents before sending a mailbox
319  * command from user space to the device. The intent is to reject
320  * commands with input payloads that are known to be unsafe. This
321  * check is not intended to replace the users careful selection of
322  * mailbox command parameters and makes no guarantee that the user
323  * command will succeed, nor that it is appropriate.
324  *
325  * The specific checks are determined by the opcode.
326  */
cxl_payload_from_user_allowed(u16 opcode,void * payload_in)327 static bool cxl_payload_from_user_allowed(u16 opcode, void *payload_in)
328 {
329 	switch (opcode) {
330 	case CXL_MBOX_OP_SET_PARTITION_INFO: {
331 		struct cxl_mbox_set_partition_info *pi = payload_in;
332 
333 		if (pi->flags & CXL_SET_PARTITION_IMMEDIATE_FLAG)
334 			return false;
335 		break;
336 	}
337 	case CXL_MBOX_OP_CLEAR_LOG: {
338 		const uuid_t *uuid = (uuid_t *)payload_in;
339 
340 		/*
341 		 * Restrict the ‘Clear log’ action to only apply to
342 		 * Vendor debug logs.
343 		 */
344 		return uuid_equal(uuid, &DEFINE_CXL_VENDOR_DEBUG_UUID);
345 	}
346 	default:
347 		break;
348 	}
349 	return true;
350 }
351 
cxl_mbox_cmd_ctor(struct cxl_mbox_cmd * mbox,struct cxl_memdev_state * mds,u16 opcode,size_t in_size,size_t out_size,u64 in_payload)352 static int cxl_mbox_cmd_ctor(struct cxl_mbox_cmd *mbox,
353 			     struct cxl_memdev_state *mds, u16 opcode,
354 			     size_t in_size, size_t out_size, u64 in_payload)
355 {
356 	struct cxl_mailbox *cxl_mbox = &mds->cxlds.cxl_mbox;
357 	*mbox = (struct cxl_mbox_cmd) {
358 		.opcode = opcode,
359 		.size_in = in_size,
360 	};
361 
362 	if (in_size) {
363 		mbox->payload_in = vmemdup_user(u64_to_user_ptr(in_payload),
364 						in_size);
365 		if (IS_ERR(mbox->payload_in))
366 			return PTR_ERR(mbox->payload_in);
367 
368 		if (!cxl_payload_from_user_allowed(opcode, mbox->payload_in)) {
369 			dev_dbg(mds->cxlds.dev, "%s: input payload not allowed\n",
370 				cxl_mem_opcode_to_name(opcode));
371 			kvfree(mbox->payload_in);
372 			return -EBUSY;
373 		}
374 	}
375 
376 	/* Prepare to handle a full payload for variable sized output */
377 	if (out_size == CXL_VARIABLE_PAYLOAD)
378 		mbox->size_out = cxl_mbox->payload_size;
379 	else
380 		mbox->size_out = out_size;
381 
382 	if (mbox->size_out) {
383 		mbox->payload_out = kvzalloc(mbox->size_out, GFP_KERNEL);
384 		if (!mbox->payload_out) {
385 			kvfree(mbox->payload_in);
386 			return -ENOMEM;
387 		}
388 	}
389 	return 0;
390 }
391 
cxl_mbox_cmd_dtor(struct cxl_mbox_cmd * mbox)392 static void cxl_mbox_cmd_dtor(struct cxl_mbox_cmd *mbox)
393 {
394 	kvfree(mbox->payload_in);
395 	kvfree(mbox->payload_out);
396 }
397 
cxl_to_mem_cmd_raw(struct cxl_mem_command * mem_cmd,const struct cxl_send_command * send_cmd,struct cxl_memdev_state * mds)398 static int cxl_to_mem_cmd_raw(struct cxl_mem_command *mem_cmd,
399 			      const struct cxl_send_command *send_cmd,
400 			      struct cxl_memdev_state *mds)
401 {
402 	struct cxl_mailbox *cxl_mbox = &mds->cxlds.cxl_mbox;
403 
404 	if (send_cmd->raw.rsvd)
405 		return -EINVAL;
406 
407 	/*
408 	 * Unlike supported commands, the output size of RAW commands
409 	 * gets passed along without further checking, so it must be
410 	 * validated here.
411 	 */
412 	if (send_cmd->out.size > cxl_mbox->payload_size)
413 		return -EINVAL;
414 
415 	if (!cxl_mem_raw_command_allowed(send_cmd->raw.opcode))
416 		return -EPERM;
417 
418 	dev_WARN_ONCE(mds->cxlds.dev, true, "raw command path used\n");
419 
420 	*mem_cmd = (struct cxl_mem_command) {
421 		.info = {
422 			.id = CXL_MEM_COMMAND_ID_RAW,
423 			.size_in = send_cmd->in.size,
424 			.size_out = send_cmd->out.size,
425 		},
426 		.opcode = send_cmd->raw.opcode
427 	};
428 
429 	return 0;
430 }
431 
cxl_to_mem_cmd(struct cxl_mem_command * mem_cmd,const struct cxl_send_command * send_cmd,struct cxl_memdev_state * mds)432 static int cxl_to_mem_cmd(struct cxl_mem_command *mem_cmd,
433 			  const struct cxl_send_command *send_cmd,
434 			  struct cxl_memdev_state *mds)
435 {
436 	struct cxl_mem_command *c = &cxl_mem_commands[send_cmd->id];
437 	const struct cxl_command_info *info = &c->info;
438 
439 	if (send_cmd->flags & ~CXL_MEM_COMMAND_FLAG_MASK)
440 		return -EINVAL;
441 
442 	if (send_cmd->rsvd)
443 		return -EINVAL;
444 
445 	if (send_cmd->in.rsvd || send_cmd->out.rsvd)
446 		return -EINVAL;
447 
448 	/* Check that the command is enabled for hardware */
449 	if (!test_bit(info->id, mds->enabled_cmds))
450 		return -ENOTTY;
451 
452 	/* Check that the command is not claimed for exclusive kernel use */
453 	if (test_bit(info->id, mds->exclusive_cmds))
454 		return -EBUSY;
455 
456 	/* Check the input buffer is the expected size */
457 	if ((info->size_in != CXL_VARIABLE_PAYLOAD) &&
458 	    (info->size_in != send_cmd->in.size))
459 		return -ENOMEM;
460 
461 	/* Check the output buffer is at least large enough */
462 	if ((info->size_out != CXL_VARIABLE_PAYLOAD) &&
463 	    (send_cmd->out.size < info->size_out))
464 		return -ENOMEM;
465 
466 	*mem_cmd = (struct cxl_mem_command) {
467 		.info = {
468 			.id = info->id,
469 			.flags = info->flags,
470 			.size_in = send_cmd->in.size,
471 			.size_out = send_cmd->out.size,
472 		},
473 		.opcode = c->opcode
474 	};
475 
476 	return 0;
477 }
478 
479 /**
480  * cxl_validate_cmd_from_user() - Check fields for CXL_MEM_SEND_COMMAND.
481  * @mbox_cmd: Sanitized and populated &struct cxl_mbox_cmd.
482  * @mds: The driver data for the operation
483  * @send_cmd: &struct cxl_send_command copied in from userspace.
484  *
485  * Return:
486  *  * %0	- @out_cmd is ready to send.
487  *  * %-ENOTTY	- Invalid command specified.
488  *  * %-EINVAL	- Reserved fields or invalid values were used.
489  *  * %-ENOMEM	- Input or output buffer wasn't sized properly.
490  *  * %-EPERM	- Attempted to use a protected command.
491  *  * %-EBUSY	- Kernel has claimed exclusive access to this opcode
492  *
493  * The result of this command is a fully validated command in @mbox_cmd that is
494  * safe to send to the hardware.
495  */
cxl_validate_cmd_from_user(struct cxl_mbox_cmd * mbox_cmd,struct cxl_memdev_state * mds,const struct cxl_send_command * send_cmd)496 static int cxl_validate_cmd_from_user(struct cxl_mbox_cmd *mbox_cmd,
497 				      struct cxl_memdev_state *mds,
498 				      const struct cxl_send_command *send_cmd)
499 {
500 	struct cxl_mailbox *cxl_mbox = &mds->cxlds.cxl_mbox;
501 	struct cxl_mem_command mem_cmd;
502 	int rc;
503 
504 	if (send_cmd->id == 0 || send_cmd->id >= CXL_MEM_COMMAND_ID_MAX)
505 		return -ENOTTY;
506 
507 	/*
508 	 * The user can never specify an input payload larger than what hardware
509 	 * supports, but output can be arbitrarily large (simply write out as
510 	 * much data as the hardware provides).
511 	 */
512 	if (send_cmd->in.size > cxl_mbox->payload_size)
513 		return -EINVAL;
514 
515 	/* Sanitize and construct a cxl_mem_command */
516 	if (send_cmd->id == CXL_MEM_COMMAND_ID_RAW)
517 		rc = cxl_to_mem_cmd_raw(&mem_cmd, send_cmd, mds);
518 	else
519 		rc = cxl_to_mem_cmd(&mem_cmd, send_cmd, mds);
520 
521 	if (rc)
522 		return rc;
523 
524 	/* Sanitize and construct a cxl_mbox_cmd */
525 	return cxl_mbox_cmd_ctor(mbox_cmd, mds, mem_cmd.opcode,
526 				 mem_cmd.info.size_in, mem_cmd.info.size_out,
527 				 send_cmd->in.payload);
528 }
529 
cxl_query_cmd(struct cxl_memdev * cxlmd,struct cxl_mem_query_commands __user * q)530 int cxl_query_cmd(struct cxl_memdev *cxlmd,
531 		  struct cxl_mem_query_commands __user *q)
532 {
533 	struct cxl_memdev_state *mds = to_cxl_memdev_state(cxlmd->cxlds);
534 	struct device *dev = &cxlmd->dev;
535 	struct cxl_mem_command *cmd;
536 	u32 n_commands;
537 	int j = 0;
538 
539 	dev_dbg(dev, "Query IOCTL\n");
540 
541 	if (get_user(n_commands, &q->n_commands))
542 		return -EFAULT;
543 
544 	/* returns the total number if 0 elements are requested. */
545 	if (n_commands == 0)
546 		return put_user(ARRAY_SIZE(cxl_mem_commands), &q->n_commands);
547 
548 	/*
549 	 * otherwise, return min(n_commands, total commands) cxl_command_info
550 	 * structures.
551 	 */
552 	cxl_for_each_cmd(cmd) {
553 		struct cxl_command_info info = cmd->info;
554 
555 		if (test_bit(info.id, mds->enabled_cmds))
556 			info.flags |= CXL_MEM_COMMAND_FLAG_ENABLED;
557 		if (test_bit(info.id, mds->exclusive_cmds))
558 			info.flags |= CXL_MEM_COMMAND_FLAG_EXCLUSIVE;
559 
560 		if (copy_to_user(&q->commands[j++], &info, sizeof(info)))
561 			return -EFAULT;
562 
563 		if (j == n_commands)
564 			break;
565 	}
566 
567 	return 0;
568 }
569 
570 /**
571  * handle_mailbox_cmd_from_user() - Dispatch a mailbox command for userspace.
572  * @mds: The driver data for the operation
573  * @mbox_cmd: The validated mailbox command.
574  * @out_payload: Pointer to userspace's output payload.
575  * @size_out: (Input) Max payload size to copy out.
576  *            (Output) Payload size hardware generated.
577  * @retval: Hardware generated return code from the operation.
578  *
579  * Return:
580  *  * %0	- Mailbox transaction succeeded. This implies the mailbox
581  *		  protocol completed successfully not that the operation itself
582  *		  was successful.
583  *  * %-ENOMEM  - Couldn't allocate a bounce buffer.
584  *  * %-EFAULT	- Something happened with copy_to/from_user.
585  *  * %-EINTR	- Mailbox acquisition interrupted.
586  *  * %-EXXX	- Transaction level failures.
587  *
588  * Dispatches a mailbox command on behalf of a userspace request.
589  * The output payload is copied to userspace.
590  *
591  * See cxl_send_cmd().
592  */
handle_mailbox_cmd_from_user(struct cxl_memdev_state * mds,struct cxl_mbox_cmd * mbox_cmd,u64 out_payload,s32 * size_out,u32 * retval)593 static int handle_mailbox_cmd_from_user(struct cxl_memdev_state *mds,
594 					struct cxl_mbox_cmd *mbox_cmd,
595 					u64 out_payload, s32 *size_out,
596 					u32 *retval)
597 {
598 	struct cxl_mailbox *cxl_mbox = &mds->cxlds.cxl_mbox;
599 	struct device *dev = mds->cxlds.dev;
600 	int rc;
601 
602 	dev_dbg(dev,
603 		"Submitting %s command for user\n"
604 		"\topcode: %x\n"
605 		"\tsize: %zx\n",
606 		cxl_mem_opcode_to_name(mbox_cmd->opcode),
607 		mbox_cmd->opcode, mbox_cmd->size_in);
608 
609 	rc = cxl_mbox->mbox_send(cxl_mbox, mbox_cmd);
610 	if (rc)
611 		goto out;
612 
613 	/*
614 	 * @size_out contains the max size that's allowed to be written back out
615 	 * to userspace. While the payload may have written more output than
616 	 * this it will have to be ignored.
617 	 */
618 	if (mbox_cmd->size_out) {
619 		dev_WARN_ONCE(dev, mbox_cmd->size_out > *size_out,
620 			      "Invalid return size\n");
621 		if (copy_to_user(u64_to_user_ptr(out_payload),
622 				 mbox_cmd->payload_out, mbox_cmd->size_out)) {
623 			rc = -EFAULT;
624 			goto out;
625 		}
626 	}
627 
628 	*size_out = mbox_cmd->size_out;
629 	*retval = mbox_cmd->return_code;
630 
631 out:
632 	cxl_mbox_cmd_dtor(mbox_cmd);
633 	return rc;
634 }
635 
cxl_send_cmd(struct cxl_memdev * cxlmd,struct cxl_send_command __user * s)636 int cxl_send_cmd(struct cxl_memdev *cxlmd, struct cxl_send_command __user *s)
637 {
638 	struct cxl_memdev_state *mds = to_cxl_memdev_state(cxlmd->cxlds);
639 	struct device *dev = &cxlmd->dev;
640 	struct cxl_send_command send;
641 	struct cxl_mbox_cmd mbox_cmd;
642 	int rc;
643 
644 	dev_dbg(dev, "Send IOCTL\n");
645 
646 	if (copy_from_user(&send, s, sizeof(send)))
647 		return -EFAULT;
648 
649 	rc = cxl_validate_cmd_from_user(&mbox_cmd, mds, &send);
650 	if (rc)
651 		return rc;
652 
653 	rc = handle_mailbox_cmd_from_user(mds, &mbox_cmd, send.out.payload,
654 					  &send.out.size, &send.retval);
655 	if (rc)
656 		return rc;
657 
658 	if (copy_to_user(s, &send, sizeof(send)))
659 		return -EFAULT;
660 
661 	return 0;
662 }
663 
cxl_xfer_log(struct cxl_memdev_state * mds,uuid_t * uuid,u32 * size,u8 * out)664 static int cxl_xfer_log(struct cxl_memdev_state *mds, uuid_t *uuid,
665 			u32 *size, u8 *out)
666 {
667 	struct cxl_mailbox *cxl_mbox = &mds->cxlds.cxl_mbox;
668 	u32 remaining = *size;
669 	u32 offset = 0;
670 
671 	while (remaining) {
672 		u32 xfer_size = min_t(u32, remaining, cxl_mbox->payload_size);
673 		struct cxl_mbox_cmd mbox_cmd;
674 		struct cxl_mbox_get_log log;
675 		int rc;
676 
677 		log = (struct cxl_mbox_get_log) {
678 			.uuid = *uuid,
679 			.offset = cpu_to_le32(offset),
680 			.length = cpu_to_le32(xfer_size),
681 		};
682 
683 		mbox_cmd = (struct cxl_mbox_cmd) {
684 			.opcode = CXL_MBOX_OP_GET_LOG,
685 			.size_in = sizeof(log),
686 			.payload_in = &log,
687 			.size_out = xfer_size,
688 			.payload_out = out,
689 		};
690 
691 		rc = cxl_internal_send_cmd(cxl_mbox, &mbox_cmd);
692 
693 		/*
694 		 * The output payload length that indicates the number
695 		 * of valid bytes can be smaller than the Log buffer
696 		 * size.
697 		 */
698 		if (rc == -EIO && mbox_cmd.size_out < xfer_size) {
699 			offset += mbox_cmd.size_out;
700 			break;
701 		}
702 
703 		if (rc < 0)
704 			return rc;
705 
706 		out += xfer_size;
707 		remaining -= xfer_size;
708 		offset += xfer_size;
709 	}
710 
711 	*size = offset;
712 
713 	return 0;
714 }
715 
716 /**
717  * cxl_walk_cel() - Walk through the Command Effects Log.
718  * @mds: The driver data for the operation
719  * @size: Length of the Command Effects Log.
720  * @cel: CEL
721  *
722  * Iterate over each entry in the CEL and determine if the driver supports the
723  * command. If so, the command is enabled for the device and can be used later.
724  */
cxl_walk_cel(struct cxl_memdev_state * mds,size_t size,u8 * cel)725 static void cxl_walk_cel(struct cxl_memdev_state *mds, size_t size, u8 *cel)
726 {
727 	struct cxl_cel_entry *cel_entry;
728 	const int cel_entries = size / sizeof(*cel_entry);
729 	struct device *dev = mds->cxlds.dev;
730 	int i;
731 
732 	cel_entry = (struct cxl_cel_entry *) cel;
733 
734 	for (i = 0; i < cel_entries; i++) {
735 		u16 opcode = le16_to_cpu(cel_entry[i].opcode);
736 		struct cxl_mem_command *cmd = cxl_mem_find_command(opcode);
737 		int enabled = 0;
738 
739 		if (cmd) {
740 			set_bit(cmd->info.id, mds->enabled_cmds);
741 			enabled++;
742 		}
743 
744 		if (cxl_is_poison_command(opcode)) {
745 			cxl_set_poison_cmd_enabled(&mds->poison, opcode);
746 			enabled++;
747 		}
748 
749 		if (cxl_is_security_command(opcode)) {
750 			cxl_set_security_cmd_enabled(&mds->security, opcode);
751 			enabled++;
752 		}
753 
754 		dev_dbg(dev, "Opcode 0x%04x %s\n", opcode,
755 			enabled ? "enabled" : "unsupported by driver");
756 	}
757 }
758 
cxl_get_gsl(struct cxl_memdev_state * mds)759 static struct cxl_mbox_get_supported_logs *cxl_get_gsl(struct cxl_memdev_state *mds)
760 {
761 	struct cxl_mailbox *cxl_mbox = &mds->cxlds.cxl_mbox;
762 	struct cxl_mbox_get_supported_logs *ret;
763 	struct cxl_mbox_cmd mbox_cmd;
764 	int rc;
765 
766 	ret = kvmalloc(cxl_mbox->payload_size, GFP_KERNEL);
767 	if (!ret)
768 		return ERR_PTR(-ENOMEM);
769 
770 	mbox_cmd = (struct cxl_mbox_cmd) {
771 		.opcode = CXL_MBOX_OP_GET_SUPPORTED_LOGS,
772 		.size_out = cxl_mbox->payload_size,
773 		.payload_out = ret,
774 		/* At least the record number field must be valid */
775 		.min_out = 2,
776 	};
777 	rc = cxl_internal_send_cmd(cxl_mbox, &mbox_cmd);
778 	if (rc < 0) {
779 		kvfree(ret);
780 		return ERR_PTR(rc);
781 	}
782 
783 
784 	return ret;
785 }
786 
787 enum {
788 	CEL_UUID,
789 	VENDOR_DEBUG_UUID,
790 };
791 
792 /* See CXL 2.0 Table 170. Get Log Input Payload */
793 static const uuid_t log_uuid[] = {
794 	[CEL_UUID] = DEFINE_CXL_CEL_UUID,
795 	[VENDOR_DEBUG_UUID] = DEFINE_CXL_VENDOR_DEBUG_UUID,
796 };
797 
798 /**
799  * cxl_enumerate_cmds() - Enumerate commands for a device.
800  * @mds: The driver data for the operation
801  *
802  * Returns 0 if enumerate completed successfully.
803  *
804  * CXL devices have optional support for certain commands. This function will
805  * determine the set of supported commands for the hardware and update the
806  * enabled_cmds bitmap in the @mds.
807  */
cxl_enumerate_cmds(struct cxl_memdev_state * mds)808 int cxl_enumerate_cmds(struct cxl_memdev_state *mds)
809 {
810 	struct cxl_mbox_get_supported_logs *gsl;
811 	struct device *dev = mds->cxlds.dev;
812 	struct cxl_mem_command *cmd;
813 	int i, rc;
814 
815 	gsl = cxl_get_gsl(mds);
816 	if (IS_ERR(gsl))
817 		return PTR_ERR(gsl);
818 
819 	rc = -ENOENT;
820 	for (i = 0; i < le16_to_cpu(gsl->entries); i++) {
821 		u32 size = le32_to_cpu(gsl->entry[i].size);
822 		uuid_t uuid = gsl->entry[i].uuid;
823 		u8 *log;
824 
825 		dev_dbg(dev, "Found LOG type %pU of size %d", &uuid, size);
826 
827 		if (!uuid_equal(&uuid, &log_uuid[CEL_UUID]))
828 			continue;
829 
830 		log = kvmalloc(size, GFP_KERNEL);
831 		if (!log) {
832 			rc = -ENOMEM;
833 			goto out;
834 		}
835 
836 		rc = cxl_xfer_log(mds, &uuid, &size, log);
837 		if (rc) {
838 			kvfree(log);
839 			goto out;
840 		}
841 
842 		cxl_walk_cel(mds, size, log);
843 		kvfree(log);
844 
845 		/* In case CEL was bogus, enable some default commands. */
846 		cxl_for_each_cmd(cmd)
847 			if (cmd->flags & CXL_CMD_FLAG_FORCE_ENABLE)
848 				set_bit(cmd->info.id, mds->enabled_cmds);
849 
850 		/* Found the required CEL */
851 		rc = 0;
852 	}
853 out:
854 	kvfree(gsl);
855 	return rc;
856 }
857 EXPORT_SYMBOL_NS_GPL(cxl_enumerate_cmds, CXL);
858 
cxl_event_trace_record(const struct cxl_memdev * cxlmd,enum cxl_event_log_type type,enum cxl_event_type event_type,const uuid_t * uuid,union cxl_event * evt)859 void cxl_event_trace_record(const struct cxl_memdev *cxlmd,
860 			    enum cxl_event_log_type type,
861 			    enum cxl_event_type event_type,
862 			    const uuid_t *uuid, union cxl_event *evt)
863 {
864 	if (event_type == CXL_CPER_EVENT_MEM_MODULE) {
865 		trace_cxl_memory_module(cxlmd, type, &evt->mem_module);
866 		return;
867 	}
868 	if (event_type == CXL_CPER_EVENT_GENERIC) {
869 		trace_cxl_generic_event(cxlmd, type, uuid, &evt->generic);
870 		return;
871 	}
872 
873 	if (trace_cxl_general_media_enabled() || trace_cxl_dram_enabled()) {
874 		u64 dpa, hpa = ULLONG_MAX;
875 		struct cxl_region *cxlr;
876 
877 		/*
878 		 * These trace points are annotated with HPA and region
879 		 * translations. Take topology mutation locks and lookup
880 		 * { HPA, REGION } from { DPA, MEMDEV } in the event record.
881 		 */
882 		guard(rwsem_read)(&cxl_region_rwsem);
883 		guard(rwsem_read)(&cxl_dpa_rwsem);
884 
885 		dpa = le64_to_cpu(evt->media_hdr.phys_addr) & CXL_DPA_MASK;
886 		cxlr = cxl_dpa_to_region(cxlmd, dpa);
887 		if (cxlr)
888 			hpa = cxl_dpa_to_hpa(cxlr, cxlmd, dpa);
889 
890 		if (event_type == CXL_CPER_EVENT_GEN_MEDIA)
891 			trace_cxl_general_media(cxlmd, type, cxlr, hpa,
892 						&evt->gen_media);
893 		else if (event_type == CXL_CPER_EVENT_DRAM)
894 			trace_cxl_dram(cxlmd, type, cxlr, hpa, &evt->dram);
895 	}
896 }
897 EXPORT_SYMBOL_NS_GPL(cxl_event_trace_record, CXL);
898 
__cxl_event_trace_record(const struct cxl_memdev * cxlmd,enum cxl_event_log_type type,struct cxl_event_record_raw * record)899 static void __cxl_event_trace_record(const struct cxl_memdev *cxlmd,
900 				     enum cxl_event_log_type type,
901 				     struct cxl_event_record_raw *record)
902 {
903 	enum cxl_event_type ev_type = CXL_CPER_EVENT_GENERIC;
904 	const uuid_t *uuid = &record->id;
905 
906 	if (uuid_equal(uuid, &CXL_EVENT_GEN_MEDIA_UUID))
907 		ev_type = CXL_CPER_EVENT_GEN_MEDIA;
908 	else if (uuid_equal(uuid, &CXL_EVENT_DRAM_UUID))
909 		ev_type = CXL_CPER_EVENT_DRAM;
910 	else if (uuid_equal(uuid, &CXL_EVENT_MEM_MODULE_UUID))
911 		ev_type = CXL_CPER_EVENT_MEM_MODULE;
912 
913 	cxl_event_trace_record(cxlmd, type, ev_type, uuid, &record->event);
914 }
915 
cxl_clear_event_record(struct cxl_memdev_state * mds,enum cxl_event_log_type log,struct cxl_get_event_payload * get_pl)916 static int cxl_clear_event_record(struct cxl_memdev_state *mds,
917 				  enum cxl_event_log_type log,
918 				  struct cxl_get_event_payload *get_pl)
919 {
920 	struct cxl_mailbox *cxl_mbox = &mds->cxlds.cxl_mbox;
921 	struct cxl_mbox_clear_event_payload *payload;
922 	u16 total = le16_to_cpu(get_pl->record_count);
923 	u8 max_handles = CXL_CLEAR_EVENT_MAX_HANDLES;
924 	size_t pl_size = struct_size(payload, handles, max_handles);
925 	struct cxl_mbox_cmd mbox_cmd;
926 	u16 cnt;
927 	int rc = 0;
928 	int i;
929 
930 	/* Payload size may limit the max handles */
931 	if (pl_size > cxl_mbox->payload_size) {
932 		max_handles = (cxl_mbox->payload_size - sizeof(*payload)) /
933 			      sizeof(__le16);
934 		pl_size = struct_size(payload, handles, max_handles);
935 	}
936 
937 	payload = kvzalloc(pl_size, GFP_KERNEL);
938 	if (!payload)
939 		return -ENOMEM;
940 
941 	*payload = (struct cxl_mbox_clear_event_payload) {
942 		.event_log = log,
943 	};
944 
945 	mbox_cmd = (struct cxl_mbox_cmd) {
946 		.opcode = CXL_MBOX_OP_CLEAR_EVENT_RECORD,
947 		.payload_in = payload,
948 		.size_in = pl_size,
949 	};
950 
951 	/*
952 	 * Clear Event Records uses u8 for the handle cnt while Get Event
953 	 * Record can return up to 0xffff records.
954 	 */
955 	i = 0;
956 	for (cnt = 0; cnt < total; cnt++) {
957 		struct cxl_event_record_raw *raw = &get_pl->records[cnt];
958 		struct cxl_event_generic *gen = &raw->event.generic;
959 
960 		payload->handles[i++] = gen->hdr.handle;
961 		dev_dbg(mds->cxlds.dev, "Event log '%d': Clearing %u\n", log,
962 			le16_to_cpu(payload->handles[i - 1]));
963 
964 		if (i == max_handles) {
965 			payload->nr_recs = i;
966 			rc = cxl_internal_send_cmd(cxl_mbox, &mbox_cmd);
967 			if (rc)
968 				goto free_pl;
969 			i = 0;
970 		}
971 	}
972 
973 	/* Clear what is left if any */
974 	if (i) {
975 		payload->nr_recs = i;
976 		mbox_cmd.size_in = struct_size(payload, handles, i);
977 		rc = cxl_internal_send_cmd(cxl_mbox, &mbox_cmd);
978 		if (rc)
979 			goto free_pl;
980 	}
981 
982 free_pl:
983 	kvfree(payload);
984 	return rc;
985 }
986 
cxl_mem_get_records_log(struct cxl_memdev_state * mds,enum cxl_event_log_type type)987 static void cxl_mem_get_records_log(struct cxl_memdev_state *mds,
988 				    enum cxl_event_log_type type)
989 {
990 	struct cxl_mailbox *cxl_mbox = &mds->cxlds.cxl_mbox;
991 	struct cxl_memdev *cxlmd = mds->cxlds.cxlmd;
992 	struct device *dev = mds->cxlds.dev;
993 	struct cxl_get_event_payload *payload;
994 	u8 log_type = type;
995 	u16 nr_rec;
996 
997 	mutex_lock(&mds->event.log_lock);
998 	payload = mds->event.buf;
999 
1000 	do {
1001 		int rc, i;
1002 		struct cxl_mbox_cmd mbox_cmd = (struct cxl_mbox_cmd) {
1003 			.opcode = CXL_MBOX_OP_GET_EVENT_RECORD,
1004 			.payload_in = &log_type,
1005 			.size_in = sizeof(log_type),
1006 			.payload_out = payload,
1007 			.size_out = cxl_mbox->payload_size,
1008 			.min_out = struct_size(payload, records, 0),
1009 		};
1010 
1011 		rc = cxl_internal_send_cmd(cxl_mbox, &mbox_cmd);
1012 		if (rc) {
1013 			dev_err_ratelimited(dev,
1014 				"Event log '%d': Failed to query event records : %d",
1015 				type, rc);
1016 			break;
1017 		}
1018 
1019 		nr_rec = le16_to_cpu(payload->record_count);
1020 		if (!nr_rec)
1021 			break;
1022 
1023 		for (i = 0; i < nr_rec; i++)
1024 			__cxl_event_trace_record(cxlmd, type,
1025 						 &payload->records[i]);
1026 
1027 		if (payload->flags & CXL_GET_EVENT_FLAG_OVERFLOW)
1028 			trace_cxl_overflow(cxlmd, type, payload);
1029 
1030 		rc = cxl_clear_event_record(mds, type, payload);
1031 		if (rc) {
1032 			dev_err_ratelimited(dev,
1033 				"Event log '%d': Failed to clear events : %d",
1034 				type, rc);
1035 			break;
1036 		}
1037 	} while (nr_rec);
1038 
1039 	mutex_unlock(&mds->event.log_lock);
1040 }
1041 
1042 /**
1043  * cxl_mem_get_event_records - Get Event Records from the device
1044  * @mds: The driver data for the operation
1045  * @status: Event Status register value identifying which events are available.
1046  *
1047  * Retrieve all event records available on the device, report them as trace
1048  * events, and clear them.
1049  *
1050  * See CXL rev 3.0 @8.2.9.2.2 Get Event Records
1051  * See CXL rev 3.0 @8.2.9.2.3 Clear Event Records
1052  */
cxl_mem_get_event_records(struct cxl_memdev_state * mds,u32 status)1053 void cxl_mem_get_event_records(struct cxl_memdev_state *mds, u32 status)
1054 {
1055 	dev_dbg(mds->cxlds.dev, "Reading event logs: %x\n", status);
1056 
1057 	if (status & CXLDEV_EVENT_STATUS_FATAL)
1058 		cxl_mem_get_records_log(mds, CXL_EVENT_TYPE_FATAL);
1059 	if (status & CXLDEV_EVENT_STATUS_FAIL)
1060 		cxl_mem_get_records_log(mds, CXL_EVENT_TYPE_FAIL);
1061 	if (status & CXLDEV_EVENT_STATUS_WARN)
1062 		cxl_mem_get_records_log(mds, CXL_EVENT_TYPE_WARN);
1063 	if (status & CXLDEV_EVENT_STATUS_INFO)
1064 		cxl_mem_get_records_log(mds, CXL_EVENT_TYPE_INFO);
1065 }
1066 EXPORT_SYMBOL_NS_GPL(cxl_mem_get_event_records, CXL);
1067 
1068 /**
1069  * cxl_mem_get_partition_info - Get partition info
1070  * @mds: The driver data for the operation
1071  *
1072  * Retrieve the current partition info for the device specified.  The active
1073  * values are the current capacity in bytes.  If not 0, the 'next' values are
1074  * the pending values, in bytes, which take affect on next cold reset.
1075  *
1076  * Return: 0 if no error: or the result of the mailbox command.
1077  *
1078  * See CXL @8.2.9.5.2.1 Get Partition Info
1079  */
cxl_mem_get_partition_info(struct cxl_memdev_state * mds)1080 static int cxl_mem_get_partition_info(struct cxl_memdev_state *mds)
1081 {
1082 	struct cxl_mailbox *cxl_mbox = &mds->cxlds.cxl_mbox;
1083 	struct cxl_mbox_get_partition_info pi;
1084 	struct cxl_mbox_cmd mbox_cmd;
1085 	int rc;
1086 
1087 	mbox_cmd = (struct cxl_mbox_cmd) {
1088 		.opcode = CXL_MBOX_OP_GET_PARTITION_INFO,
1089 		.size_out = sizeof(pi),
1090 		.payload_out = &pi,
1091 	};
1092 	rc = cxl_internal_send_cmd(cxl_mbox, &mbox_cmd);
1093 	if (rc)
1094 		return rc;
1095 
1096 	mds->active_volatile_bytes =
1097 		le64_to_cpu(pi.active_volatile_cap) * CXL_CAPACITY_MULTIPLIER;
1098 	mds->active_persistent_bytes =
1099 		le64_to_cpu(pi.active_persistent_cap) * CXL_CAPACITY_MULTIPLIER;
1100 	mds->next_volatile_bytes =
1101 		le64_to_cpu(pi.next_volatile_cap) * CXL_CAPACITY_MULTIPLIER;
1102 	mds->next_persistent_bytes =
1103 		le64_to_cpu(pi.next_volatile_cap) * CXL_CAPACITY_MULTIPLIER;
1104 
1105 	return 0;
1106 }
1107 
1108 /**
1109  * cxl_dev_state_identify() - Send the IDENTIFY command to the device.
1110  * @mds: The driver data for the operation
1111  *
1112  * Return: 0 if identify was executed successfully or media not ready.
1113  *
1114  * This will dispatch the identify command to the device and on success populate
1115  * structures to be exported to sysfs.
1116  */
cxl_dev_state_identify(struct cxl_memdev_state * mds)1117 int cxl_dev_state_identify(struct cxl_memdev_state *mds)
1118 {
1119 	struct cxl_mailbox *cxl_mbox = &mds->cxlds.cxl_mbox;
1120 	/* See CXL 2.0 Table 175 Identify Memory Device Output Payload */
1121 	struct cxl_mbox_identify id;
1122 	struct cxl_mbox_cmd mbox_cmd;
1123 	u32 val;
1124 	int rc;
1125 
1126 	if (!mds->cxlds.media_ready)
1127 		return 0;
1128 
1129 	mbox_cmd = (struct cxl_mbox_cmd) {
1130 		.opcode = CXL_MBOX_OP_IDENTIFY,
1131 		.size_out = sizeof(id),
1132 		.payload_out = &id,
1133 	};
1134 	rc = cxl_internal_send_cmd(cxl_mbox, &mbox_cmd);
1135 	if (rc < 0)
1136 		return rc;
1137 
1138 	mds->total_bytes =
1139 		le64_to_cpu(id.total_capacity) * CXL_CAPACITY_MULTIPLIER;
1140 	mds->volatile_only_bytes =
1141 		le64_to_cpu(id.volatile_capacity) * CXL_CAPACITY_MULTIPLIER;
1142 	mds->persistent_only_bytes =
1143 		le64_to_cpu(id.persistent_capacity) * CXL_CAPACITY_MULTIPLIER;
1144 	mds->partition_align_bytes =
1145 		le64_to_cpu(id.partition_align) * CXL_CAPACITY_MULTIPLIER;
1146 
1147 	mds->lsa_size = le32_to_cpu(id.lsa_size);
1148 	memcpy(mds->firmware_version, id.fw_revision,
1149 	       sizeof(id.fw_revision));
1150 
1151 	if (test_bit(CXL_POISON_ENABLED_LIST, mds->poison.enabled_cmds)) {
1152 		val = get_unaligned_le24(id.poison_list_max_mer);
1153 		mds->poison.max_errors = min_t(u32, val, CXL_POISON_LIST_MAX);
1154 	}
1155 
1156 	return 0;
1157 }
1158 EXPORT_SYMBOL_NS_GPL(cxl_dev_state_identify, CXL);
1159 
__cxl_mem_sanitize(struct cxl_memdev_state * mds,u16 cmd)1160 static int __cxl_mem_sanitize(struct cxl_memdev_state *mds, u16 cmd)
1161 {
1162 	struct cxl_mailbox *cxl_mbox = &mds->cxlds.cxl_mbox;
1163 	int rc;
1164 	u32 sec_out = 0;
1165 	struct cxl_get_security_output {
1166 		__le32 flags;
1167 	} out;
1168 	struct cxl_mbox_cmd sec_cmd = {
1169 		.opcode = CXL_MBOX_OP_GET_SECURITY_STATE,
1170 		.payload_out = &out,
1171 		.size_out = sizeof(out),
1172 	};
1173 	struct cxl_mbox_cmd mbox_cmd = { .opcode = cmd };
1174 
1175 	if (cmd != CXL_MBOX_OP_SANITIZE && cmd != CXL_MBOX_OP_SECURE_ERASE)
1176 		return -EINVAL;
1177 
1178 	rc = cxl_internal_send_cmd(cxl_mbox, &sec_cmd);
1179 	if (rc < 0) {
1180 		dev_err(cxl_mbox->host, "Failed to get security state : %d", rc);
1181 		return rc;
1182 	}
1183 
1184 	/*
1185 	 * Prior to using these commands, any security applied to
1186 	 * the user data areas of the device shall be DISABLED (or
1187 	 * UNLOCKED for secure erase case).
1188 	 */
1189 	sec_out = le32_to_cpu(out.flags);
1190 	if (sec_out & CXL_PMEM_SEC_STATE_USER_PASS_SET)
1191 		return -EINVAL;
1192 
1193 	if (cmd == CXL_MBOX_OP_SECURE_ERASE &&
1194 	    sec_out & CXL_PMEM_SEC_STATE_LOCKED)
1195 		return -EINVAL;
1196 
1197 	rc = cxl_internal_send_cmd(cxl_mbox, &mbox_cmd);
1198 	if (rc < 0) {
1199 		dev_err(cxl_mbox->host, "Failed to sanitize device : %d", rc);
1200 		return rc;
1201 	}
1202 
1203 	return 0;
1204 }
1205 
1206 
1207 /**
1208  * cxl_mem_sanitize() - Send a sanitization command to the device.
1209  * @cxlmd: The device for the operation
1210  * @cmd: The specific sanitization command opcode
1211  *
1212  * Return: 0 if the command was executed successfully, regardless of
1213  * whether or not the actual security operation is done in the background,
1214  * such as for the Sanitize case.
1215  * Error return values can be the result of the mailbox command, -EINVAL
1216  * when security requirements are not met or invalid contexts, or -EBUSY
1217  * if the sanitize operation is already in flight.
1218  *
1219  * See CXL 3.0 @8.2.9.8.5.1 Sanitize and @8.2.9.8.5.2 Secure Erase.
1220  */
cxl_mem_sanitize(struct cxl_memdev * cxlmd,u16 cmd)1221 int cxl_mem_sanitize(struct cxl_memdev *cxlmd, u16 cmd)
1222 {
1223 	struct cxl_memdev_state *mds = to_cxl_memdev_state(cxlmd->cxlds);
1224 	struct cxl_port  *endpoint;
1225 	int rc;
1226 
1227 	/* synchronize with cxl_mem_probe() and decoder write operations */
1228 	guard(device)(&cxlmd->dev);
1229 	endpoint = cxlmd->endpoint;
1230 	down_read(&cxl_region_rwsem);
1231 	/*
1232 	 * Require an endpoint to be safe otherwise the driver can not
1233 	 * be sure that the device is unmapped.
1234 	 */
1235 	if (endpoint && cxl_num_decoders_committed(endpoint) == 0)
1236 		rc = __cxl_mem_sanitize(mds, cmd);
1237 	else
1238 		rc = -EBUSY;
1239 	up_read(&cxl_region_rwsem);
1240 
1241 	return rc;
1242 }
1243 
add_dpa_res(struct device * dev,struct resource * parent,struct resource * res,resource_size_t start,resource_size_t size,const char * type)1244 static int add_dpa_res(struct device *dev, struct resource *parent,
1245 		       struct resource *res, resource_size_t start,
1246 		       resource_size_t size, const char *type)
1247 {
1248 	int rc;
1249 
1250 	res->name = type;
1251 	res->start = start;
1252 	res->end = start + size - 1;
1253 	res->flags = IORESOURCE_MEM;
1254 	if (resource_size(res) == 0) {
1255 		dev_dbg(dev, "DPA(%s): no capacity\n", res->name);
1256 		return 0;
1257 	}
1258 	rc = request_resource(parent, res);
1259 	if (rc) {
1260 		dev_err(dev, "DPA(%s): failed to track %pr (%d)\n", res->name,
1261 			res, rc);
1262 		return rc;
1263 	}
1264 
1265 	dev_dbg(dev, "DPA(%s): %pr\n", res->name, res);
1266 
1267 	return 0;
1268 }
1269 
cxl_mem_create_range_info(struct cxl_memdev_state * mds)1270 int cxl_mem_create_range_info(struct cxl_memdev_state *mds)
1271 {
1272 	struct cxl_dev_state *cxlds = &mds->cxlds;
1273 	struct device *dev = cxlds->dev;
1274 	int rc;
1275 
1276 	if (!cxlds->media_ready) {
1277 		cxlds->dpa_res = DEFINE_RES_MEM(0, 0);
1278 		cxlds->ram_res = DEFINE_RES_MEM(0, 0);
1279 		cxlds->pmem_res = DEFINE_RES_MEM(0, 0);
1280 		return 0;
1281 	}
1282 
1283 	cxlds->dpa_res = DEFINE_RES_MEM(0, mds->total_bytes);
1284 
1285 	if (mds->partition_align_bytes == 0) {
1286 		rc = add_dpa_res(dev, &cxlds->dpa_res, &cxlds->ram_res, 0,
1287 				 mds->volatile_only_bytes, "ram");
1288 		if (rc)
1289 			return rc;
1290 		return add_dpa_res(dev, &cxlds->dpa_res, &cxlds->pmem_res,
1291 				   mds->volatile_only_bytes,
1292 				   mds->persistent_only_bytes, "pmem");
1293 	}
1294 
1295 	rc = cxl_mem_get_partition_info(mds);
1296 	if (rc) {
1297 		dev_err(dev, "Failed to query partition information\n");
1298 		return rc;
1299 	}
1300 
1301 	rc = add_dpa_res(dev, &cxlds->dpa_res, &cxlds->ram_res, 0,
1302 			 mds->active_volatile_bytes, "ram");
1303 	if (rc)
1304 		return rc;
1305 	return add_dpa_res(dev, &cxlds->dpa_res, &cxlds->pmem_res,
1306 			   mds->active_volatile_bytes,
1307 			   mds->active_persistent_bytes, "pmem");
1308 }
1309 EXPORT_SYMBOL_NS_GPL(cxl_mem_create_range_info, CXL);
1310 
cxl_set_timestamp(struct cxl_memdev_state * mds)1311 int cxl_set_timestamp(struct cxl_memdev_state *mds)
1312 {
1313 	struct cxl_mailbox *cxl_mbox = &mds->cxlds.cxl_mbox;
1314 	struct cxl_mbox_cmd mbox_cmd;
1315 	struct cxl_mbox_set_timestamp_in pi;
1316 	int rc;
1317 
1318 	pi.timestamp = cpu_to_le64(ktime_get_real_ns());
1319 	mbox_cmd = (struct cxl_mbox_cmd) {
1320 		.opcode = CXL_MBOX_OP_SET_TIMESTAMP,
1321 		.size_in = sizeof(pi),
1322 		.payload_in = &pi,
1323 	};
1324 
1325 	rc = cxl_internal_send_cmd(cxl_mbox, &mbox_cmd);
1326 	/*
1327 	 * Command is optional. Devices may have another way of providing
1328 	 * a timestamp, or may return all 0s in timestamp fields.
1329 	 * Don't report an error if this command isn't supported
1330 	 */
1331 	if (rc && (mbox_cmd.return_code != CXL_MBOX_CMD_RC_UNSUPPORTED))
1332 		return rc;
1333 
1334 	return 0;
1335 }
1336 EXPORT_SYMBOL_NS_GPL(cxl_set_timestamp, CXL);
1337 
cxl_mem_get_poison(struct cxl_memdev * cxlmd,u64 offset,u64 len,struct cxl_region * cxlr)1338 int cxl_mem_get_poison(struct cxl_memdev *cxlmd, u64 offset, u64 len,
1339 		       struct cxl_region *cxlr)
1340 {
1341 	struct cxl_memdev_state *mds = to_cxl_memdev_state(cxlmd->cxlds);
1342 	struct cxl_mailbox *cxl_mbox = &cxlmd->cxlds->cxl_mbox;
1343 	struct cxl_mbox_poison_out *po;
1344 	struct cxl_mbox_poison_in pi;
1345 	int nr_records = 0;
1346 	int rc;
1347 
1348 	rc = mutex_lock_interruptible(&mds->poison.lock);
1349 	if (rc)
1350 		return rc;
1351 
1352 	po = mds->poison.list_out;
1353 	pi.offset = cpu_to_le64(offset);
1354 	pi.length = cpu_to_le64(len / CXL_POISON_LEN_MULT);
1355 
1356 	do {
1357 		struct cxl_mbox_cmd mbox_cmd = (struct cxl_mbox_cmd){
1358 			.opcode = CXL_MBOX_OP_GET_POISON,
1359 			.size_in = sizeof(pi),
1360 			.payload_in = &pi,
1361 			.size_out = cxl_mbox->payload_size,
1362 			.payload_out = po,
1363 			.min_out = struct_size(po, record, 0),
1364 		};
1365 
1366 		rc = cxl_internal_send_cmd(cxl_mbox, &mbox_cmd);
1367 		if (rc)
1368 			break;
1369 
1370 		for (int i = 0; i < le16_to_cpu(po->count); i++)
1371 			trace_cxl_poison(cxlmd, cxlr, &po->record[i],
1372 					 po->flags, po->overflow_ts,
1373 					 CXL_POISON_TRACE_LIST);
1374 
1375 		/* Protect against an uncleared _FLAG_MORE */
1376 		nr_records = nr_records + le16_to_cpu(po->count);
1377 		if (nr_records >= mds->poison.max_errors) {
1378 			dev_dbg(&cxlmd->dev, "Max Error Records reached: %d\n",
1379 				nr_records);
1380 			break;
1381 		}
1382 	} while (po->flags & CXL_POISON_FLAG_MORE);
1383 
1384 	mutex_unlock(&mds->poison.lock);
1385 	return rc;
1386 }
1387 EXPORT_SYMBOL_NS_GPL(cxl_mem_get_poison, CXL);
1388 
free_poison_buf(void * buf)1389 static void free_poison_buf(void *buf)
1390 {
1391 	kvfree(buf);
1392 }
1393 
1394 /* Get Poison List output buffer is protected by mds->poison.lock */
cxl_poison_alloc_buf(struct cxl_memdev_state * mds)1395 static int cxl_poison_alloc_buf(struct cxl_memdev_state *mds)
1396 {
1397 	struct cxl_mailbox *cxl_mbox = &mds->cxlds.cxl_mbox;
1398 
1399 	mds->poison.list_out = kvmalloc(cxl_mbox->payload_size, GFP_KERNEL);
1400 	if (!mds->poison.list_out)
1401 		return -ENOMEM;
1402 
1403 	return devm_add_action_or_reset(mds->cxlds.dev, free_poison_buf,
1404 					mds->poison.list_out);
1405 }
1406 
cxl_poison_state_init(struct cxl_memdev_state * mds)1407 int cxl_poison_state_init(struct cxl_memdev_state *mds)
1408 {
1409 	int rc;
1410 
1411 	if (!test_bit(CXL_POISON_ENABLED_LIST, mds->poison.enabled_cmds))
1412 		return 0;
1413 
1414 	rc = cxl_poison_alloc_buf(mds);
1415 	if (rc) {
1416 		clear_bit(CXL_POISON_ENABLED_LIST, mds->poison.enabled_cmds);
1417 		return rc;
1418 	}
1419 
1420 	mutex_init(&mds->poison.lock);
1421 	return 0;
1422 }
1423 EXPORT_SYMBOL_NS_GPL(cxl_poison_state_init, CXL);
1424 
cxl_mailbox_init(struct cxl_mailbox * cxl_mbox,struct device * host)1425 int cxl_mailbox_init(struct cxl_mailbox *cxl_mbox, struct device *host)
1426 {
1427 	if (!cxl_mbox || !host)
1428 		return -EINVAL;
1429 
1430 	cxl_mbox->host = host;
1431 	mutex_init(&cxl_mbox->mbox_mutex);
1432 	rcuwait_init(&cxl_mbox->mbox_wait);
1433 
1434 	return 0;
1435 }
1436 EXPORT_SYMBOL_NS_GPL(cxl_mailbox_init, CXL);
1437 
cxl_memdev_state_create(struct device * dev)1438 struct cxl_memdev_state *cxl_memdev_state_create(struct device *dev)
1439 {
1440 	struct cxl_memdev_state *mds;
1441 
1442 	mds = devm_kzalloc(dev, sizeof(*mds), GFP_KERNEL);
1443 	if (!mds) {
1444 		dev_err(dev, "No memory available\n");
1445 		return ERR_PTR(-ENOMEM);
1446 	}
1447 
1448 	mutex_init(&mds->event.log_lock);
1449 	mds->cxlds.dev = dev;
1450 	mds->cxlds.reg_map.host = dev;
1451 	mds->cxlds.reg_map.resource = CXL_RESOURCE_NONE;
1452 	mds->cxlds.type = CXL_DEVTYPE_CLASSMEM;
1453 	mds->ram_perf.qos_class = CXL_QOS_CLASS_INVALID;
1454 	mds->pmem_perf.qos_class = CXL_QOS_CLASS_INVALID;
1455 
1456 	return mds;
1457 }
1458 EXPORT_SYMBOL_NS_GPL(cxl_memdev_state_create, CXL);
1459 
cxl_mbox_init(void)1460 void __init cxl_mbox_init(void)
1461 {
1462 	struct dentry *mbox_debugfs;
1463 
1464 	mbox_debugfs = cxl_debugfs_create_dir("mbox");
1465 	debugfs_create_bool("raw_allow_all", 0600, mbox_debugfs,
1466 			    &cxl_raw_allow_all);
1467 }
1468