xref: /linux/drivers/cxl/core/mbox.c (revision d41e5839d80043beaa63973eab602579ebdb238f)
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 #include "mce.h"
15 
16 static bool cxl_raw_allow_all;
17 
18 /**
19  * DOC: cxl mbox
20  *
21  * Core implementation of the CXL 2.0 Type-3 Memory Device Mailbox. The
22  * implementation is used by the cxl_pci driver to initialize the device
23  * and implement the cxl_mem.h IOCTL UAPI. It also implements the
24  * backend of the cxl_pmem_ctl() transport for LIBNVDIMM.
25  */
26 
27 #define cxl_for_each_cmd(cmd)                                                  \
28 	for ((cmd) = &cxl_mem_commands[0];                                     \
29 	     ((cmd) - cxl_mem_commands) < ARRAY_SIZE(cxl_mem_commands); (cmd)++)
30 
31 #define CXL_CMD(_id, sin, sout, _flags)                                        \
32 	[CXL_MEM_COMMAND_ID_##_id] = {                                         \
33 	.info =	{                                                              \
34 			.id = CXL_MEM_COMMAND_ID_##_id,                        \
35 			.size_in = sin,                                        \
36 			.size_out = sout,                                      \
37 		},                                                             \
38 	.opcode = CXL_MBOX_OP_##_id,                                           \
39 	.flags = _flags,                                                       \
40 	}
41 
42 #define CXL_VARIABLE_PAYLOAD	~0U
43 /*
44  * This table defines the supported mailbox commands for the driver. This table
45  * is made up of a UAPI structure. Non-negative values as parameters in the
46  * table will be validated against the user's input. For example, if size_in is
47  * 0, and the user passed in 1, it is an error.
48  */
49 static struct cxl_mem_command cxl_mem_commands[CXL_MEM_COMMAND_ID_MAX] = {
50 	CXL_CMD(IDENTIFY, 0, 0x43, CXL_CMD_FLAG_FORCE_ENABLE),
51 #ifdef CONFIG_CXL_MEM_RAW_COMMANDS
52 	CXL_CMD(RAW, CXL_VARIABLE_PAYLOAD, CXL_VARIABLE_PAYLOAD, 0),
53 #endif
54 	CXL_CMD(GET_SUPPORTED_LOGS, 0, CXL_VARIABLE_PAYLOAD, CXL_CMD_FLAG_FORCE_ENABLE),
55 	CXL_CMD(GET_FW_INFO, 0, 0x50, 0),
56 	CXL_CMD(GET_PARTITION_INFO, 0, 0x20, 0),
57 	CXL_CMD(GET_LSA, 0x8, CXL_VARIABLE_PAYLOAD, 0),
58 	CXL_CMD(GET_HEALTH_INFO, 0, 0x12, 0),
59 	CXL_CMD(GET_LOG, 0x18, CXL_VARIABLE_PAYLOAD, CXL_CMD_FLAG_FORCE_ENABLE),
60 	CXL_CMD(GET_LOG_CAPS, 0x10, 0x4, 0),
61 	CXL_CMD(CLEAR_LOG, 0x10, 0, 0),
62 	CXL_CMD(GET_SUP_LOG_SUBLIST, 0x2, CXL_VARIABLE_PAYLOAD, 0),
63 	CXL_CMD(SET_PARTITION_INFO, 0x0a, 0, 0),
64 	CXL_CMD(SET_LSA, CXL_VARIABLE_PAYLOAD, 0, 0),
65 	CXL_CMD(GET_ALERT_CONFIG, 0, 0x10, 0),
66 	CXL_CMD(SET_ALERT_CONFIG, 0xc, 0, 0),
67 	CXL_CMD(GET_SHUTDOWN_STATE, 0, 0x1, 0),
68 	CXL_CMD(SET_SHUTDOWN_STATE, 0x1, 0, 0),
69 	CXL_CMD(GET_SCAN_MEDIA_CAPS, 0x10, 0x4, 0),
70 	CXL_CMD(GET_TIMESTAMP, 0, 0x8, 0),
71 };
72 
73 /*
74  * Commands that RAW doesn't permit. The rationale for each:
75  *
76  * CXL_MBOX_OP_ACTIVATE_FW: Firmware activation requires adjustment /
77  * coordination of transaction timeout values at the root bridge level.
78  *
79  * CXL_MBOX_OP_SET_PARTITION_INFO: The device memory map may change live
80  * and needs to be coordinated with HDM updates.
81  *
82  * CXL_MBOX_OP_SET_LSA: The label storage area may be cached by the
83  * driver and any writes from userspace invalidates those contents.
84  *
85  * CXL_MBOX_OP_SET_SHUTDOWN_STATE: Set shutdown state assumes no writes
86  * to the device after it is marked clean, userspace can not make that
87  * assertion.
88  *
89  * CXL_MBOX_OP_[GET_]SCAN_MEDIA: The kernel provides a native error list that
90  * is kept up to date with patrol notifications and error management.
91  *
92  * CXL_MBOX_OP_[GET_,INJECT_,CLEAR_]POISON: These commands require kernel
93  * driver orchestration for safety.
94  */
95 static u16 cxl_disabled_raw_commands[] = {
96 	CXL_MBOX_OP_ACTIVATE_FW,
97 	CXL_MBOX_OP_SET_PARTITION_INFO,
98 	CXL_MBOX_OP_SET_LSA,
99 	CXL_MBOX_OP_SET_SHUTDOWN_STATE,
100 	CXL_MBOX_OP_SCAN_MEDIA,
101 	CXL_MBOX_OP_GET_SCAN_MEDIA,
102 	CXL_MBOX_OP_GET_POISON,
103 	CXL_MBOX_OP_INJECT_POISON,
104 	CXL_MBOX_OP_CLEAR_POISON,
105 };
106 
107 /*
108  * Command sets that RAW doesn't permit. All opcodes in this set are
109  * disabled because they pass plain text security payloads over the
110  * user/kernel boundary. This functionality is intended to be wrapped
111  * behind the keys ABI which allows for encrypted payloads in the UAPI
112  */
113 static u8 security_command_sets[] = {
114 	0x44, /* Sanitize */
115 	0x45, /* Persistent Memory Data-at-rest Security */
116 	0x46, /* Security Passthrough */
117 };
118 
cxl_is_security_command(u16 opcode)119 static bool cxl_is_security_command(u16 opcode)
120 {
121 	int i;
122 
123 	for (i = 0; i < ARRAY_SIZE(security_command_sets); i++)
124 		if (security_command_sets[i] == (opcode >> 8))
125 			return true;
126 	return false;
127 }
128 
cxl_set_security_cmd_enabled(struct cxl_security_state * security,u16 opcode)129 static void cxl_set_security_cmd_enabled(struct cxl_security_state *security,
130 					 u16 opcode)
131 {
132 	switch (opcode) {
133 	case CXL_MBOX_OP_SANITIZE:
134 		set_bit(CXL_SEC_ENABLED_SANITIZE, security->enabled_cmds);
135 		break;
136 	case CXL_MBOX_OP_SECURE_ERASE:
137 		set_bit(CXL_SEC_ENABLED_SECURE_ERASE,
138 			security->enabled_cmds);
139 		break;
140 	case CXL_MBOX_OP_GET_SECURITY_STATE:
141 		set_bit(CXL_SEC_ENABLED_GET_SECURITY_STATE,
142 			security->enabled_cmds);
143 		break;
144 	case CXL_MBOX_OP_SET_PASSPHRASE:
145 		set_bit(CXL_SEC_ENABLED_SET_PASSPHRASE,
146 			security->enabled_cmds);
147 		break;
148 	case CXL_MBOX_OP_DISABLE_PASSPHRASE:
149 		set_bit(CXL_SEC_ENABLED_DISABLE_PASSPHRASE,
150 			security->enabled_cmds);
151 		break;
152 	case CXL_MBOX_OP_UNLOCK:
153 		set_bit(CXL_SEC_ENABLED_UNLOCK, security->enabled_cmds);
154 		break;
155 	case CXL_MBOX_OP_FREEZE_SECURITY:
156 		set_bit(CXL_SEC_ENABLED_FREEZE_SECURITY,
157 			security->enabled_cmds);
158 		break;
159 	case CXL_MBOX_OP_PASSPHRASE_SECURE_ERASE:
160 		set_bit(CXL_SEC_ENABLED_PASSPHRASE_SECURE_ERASE,
161 			security->enabled_cmds);
162 		break;
163 	default:
164 		break;
165 	}
166 }
167 
cxl_is_poison_command(u16 opcode)168 static bool cxl_is_poison_command(u16 opcode)
169 {
170 #define CXL_MBOX_OP_POISON_CMDS 0x43
171 
172 	if ((opcode >> 8) == CXL_MBOX_OP_POISON_CMDS)
173 		return true;
174 
175 	return false;
176 }
177 
cxl_set_poison_cmd_enabled(struct cxl_poison_state * poison,u16 opcode)178 static void cxl_set_poison_cmd_enabled(struct cxl_poison_state *poison,
179 				       u16 opcode)
180 {
181 	switch (opcode) {
182 	case CXL_MBOX_OP_GET_POISON:
183 		set_bit(CXL_POISON_ENABLED_LIST, poison->enabled_cmds);
184 		break;
185 	case CXL_MBOX_OP_INJECT_POISON:
186 		set_bit(CXL_POISON_ENABLED_INJECT, poison->enabled_cmds);
187 		break;
188 	case CXL_MBOX_OP_CLEAR_POISON:
189 		set_bit(CXL_POISON_ENABLED_CLEAR, poison->enabled_cmds);
190 		break;
191 	case CXL_MBOX_OP_GET_SCAN_MEDIA_CAPS:
192 		set_bit(CXL_POISON_ENABLED_SCAN_CAPS, poison->enabled_cmds);
193 		break;
194 	case CXL_MBOX_OP_SCAN_MEDIA:
195 		set_bit(CXL_POISON_ENABLED_SCAN_MEDIA, poison->enabled_cmds);
196 		break;
197 	case CXL_MBOX_OP_GET_SCAN_MEDIA:
198 		set_bit(CXL_POISON_ENABLED_SCAN_RESULTS, poison->enabled_cmds);
199 		break;
200 	default:
201 		break;
202 	}
203 }
204 
cxl_mem_find_command(u16 opcode)205 static struct cxl_mem_command *cxl_mem_find_command(u16 opcode)
206 {
207 	struct cxl_mem_command *c;
208 
209 	cxl_for_each_cmd(c)
210 		if (c->opcode == opcode)
211 			return c;
212 
213 	return NULL;
214 }
215 
cxl_mem_opcode_to_name(u16 opcode)216 static const char *cxl_mem_opcode_to_name(u16 opcode)
217 {
218 	struct cxl_mem_command *c;
219 
220 	c = cxl_mem_find_command(opcode);
221 	if (!c)
222 		return NULL;
223 
224 	return cxl_command_names[c->info.id].name;
225 }
226 
227 /**
228  * cxl_internal_send_cmd() - Kernel internal interface to send a mailbox command
229  * @cxl_mbox: CXL mailbox context
230  * @mbox_cmd: initialized command to execute
231  *
232  * Context: Any context.
233  * Return:
234  *  * %>=0	- Number of bytes returned in @out.
235  *  * %-E2BIG	- Payload is too large for hardware.
236  *  * %-EBUSY	- Couldn't acquire exclusive mailbox access.
237  *  * %-EFAULT	- Hardware error occurred.
238  *  * %-ENXIO	- Command completed, but device reported an error.
239  *  * %-EIO	- Unexpected output size.
240  *
241  * Mailbox commands may execute successfully yet the device itself reported an
242  * error. While this distinction can be useful for commands from userspace, the
243  * kernel will only be able to use results when both are successful.
244  */
cxl_internal_send_cmd(struct cxl_mailbox * cxl_mbox,struct cxl_mbox_cmd * mbox_cmd)245 int cxl_internal_send_cmd(struct cxl_mailbox *cxl_mbox,
246 			  struct cxl_mbox_cmd *mbox_cmd)
247 {
248 	size_t out_size, min_out;
249 	int rc;
250 
251 	if (mbox_cmd->size_in > cxl_mbox->payload_size ||
252 	    mbox_cmd->size_out > cxl_mbox->payload_size)
253 		return -E2BIG;
254 
255 	out_size = mbox_cmd->size_out;
256 	min_out = mbox_cmd->min_out;
257 	rc = cxl_mbox->mbox_send(cxl_mbox, mbox_cmd);
258 	/*
259 	 * EIO is reserved for a payload size mismatch and mbox_send()
260 	 * may not return this error.
261 	 */
262 	if (WARN_ONCE(rc == -EIO, "Bad return code: -EIO"))
263 		return -ENXIO;
264 	if (rc)
265 		return rc;
266 
267 	if (mbox_cmd->return_code != CXL_MBOX_CMD_RC_SUCCESS &&
268 	    mbox_cmd->return_code != CXL_MBOX_CMD_RC_BACKGROUND)
269 		return cxl_mbox_cmd_rc2errno(mbox_cmd);
270 
271 	if (!out_size)
272 		return 0;
273 
274 	/*
275 	 * Variable sized output needs to at least satisfy the caller's
276 	 * minimum if not the fully requested size.
277 	 */
278 	if (min_out == 0)
279 		min_out = out_size;
280 
281 	if (mbox_cmd->size_out < min_out)
282 		return -EIO;
283 	return 0;
284 }
285 EXPORT_SYMBOL_NS_GPL(cxl_internal_send_cmd, "CXL");
286 
cxl_mem_raw_command_allowed(u16 opcode)287 static bool cxl_mem_raw_command_allowed(u16 opcode)
288 {
289 	int i;
290 
291 	if (!IS_ENABLED(CONFIG_CXL_MEM_RAW_COMMANDS))
292 		return false;
293 
294 	if (security_locked_down(LOCKDOWN_PCI_ACCESS))
295 		return false;
296 
297 	if (cxl_raw_allow_all)
298 		return true;
299 
300 	if (cxl_is_security_command(opcode))
301 		return false;
302 
303 	for (i = 0; i < ARRAY_SIZE(cxl_disabled_raw_commands); i++)
304 		if (cxl_disabled_raw_commands[i] == opcode)
305 			return false;
306 
307 	return true;
308 }
309 
310 /**
311  * cxl_payload_from_user_allowed() - Check contents of in_payload.
312  * @opcode: The mailbox command opcode.
313  * @payload_in: Pointer to the input payload passed in from user space.
314  *
315  * Return:
316  *  * true	- payload_in passes check for @opcode.
317  *  * false	- payload_in contains invalid or unsupported values.
318  *
319  * The driver may inspect payload contents before sending a mailbox
320  * command from user space to the device. The intent is to reject
321  * commands with input payloads that are known to be unsafe. This
322  * check is not intended to replace the users careful selection of
323  * mailbox command parameters and makes no guarantee that the user
324  * command will succeed, nor that it is appropriate.
325  *
326  * The specific checks are determined by the opcode.
327  */
cxl_payload_from_user_allowed(u16 opcode,void * payload_in)328 static bool cxl_payload_from_user_allowed(u16 opcode, void *payload_in)
329 {
330 	switch (opcode) {
331 	case CXL_MBOX_OP_SET_PARTITION_INFO: {
332 		struct cxl_mbox_set_partition_info *pi = payload_in;
333 
334 		if (pi->flags & CXL_SET_PARTITION_IMMEDIATE_FLAG)
335 			return false;
336 		break;
337 	}
338 	case CXL_MBOX_OP_CLEAR_LOG: {
339 		const uuid_t *uuid = (uuid_t *)payload_in;
340 
341 		/*
342 		 * Restrict the ‘Clear log’ action to only apply to
343 		 * Vendor debug logs.
344 		 */
345 		return uuid_equal(uuid, &DEFINE_CXL_VENDOR_DEBUG_UUID);
346 	}
347 	default:
348 		break;
349 	}
350 	return true;
351 }
352 
cxl_mbox_cmd_ctor(struct cxl_mbox_cmd * mbox_cmd,struct cxl_mailbox * cxl_mbox,u16 opcode,size_t in_size,size_t out_size,u64 in_payload)353 static int cxl_mbox_cmd_ctor(struct cxl_mbox_cmd *mbox_cmd,
354 			     struct cxl_mailbox *cxl_mbox, u16 opcode,
355 			     size_t in_size, size_t out_size, u64 in_payload)
356 {
357 	*mbox_cmd = (struct cxl_mbox_cmd) {
358 		.opcode = opcode,
359 		.size_in = in_size,
360 	};
361 
362 	if (in_size) {
363 		mbox_cmd->payload_in = vmemdup_user(u64_to_user_ptr(in_payload),
364 						    in_size);
365 		if (IS_ERR(mbox_cmd->payload_in))
366 			return PTR_ERR(mbox_cmd->payload_in);
367 
368 		if (!cxl_payload_from_user_allowed(opcode, mbox_cmd->payload_in)) {
369 			dev_dbg(cxl_mbox->host, "%s: input payload not allowed\n",
370 				cxl_mem_opcode_to_name(opcode));
371 			kvfree(mbox_cmd->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_cmd->size_out = cxl_mbox->payload_size;
379 	else
380 		mbox_cmd->size_out = out_size;
381 
382 	if (mbox_cmd->size_out) {
383 		mbox_cmd->payload_out = kvzalloc(mbox_cmd->size_out, GFP_KERNEL);
384 		if (!mbox_cmd->payload_out) {
385 			kvfree(mbox_cmd->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_mailbox * cxl_mbox)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_mailbox *cxl_mbox)
401 {
402 	if (send_cmd->raw.rsvd)
403 		return -EINVAL;
404 
405 	/*
406 	 * Unlike supported commands, the output size of RAW commands
407 	 * gets passed along without further checking, so it must be
408 	 * validated here.
409 	 */
410 	if (send_cmd->out.size > cxl_mbox->payload_size)
411 		return -EINVAL;
412 
413 	if (!cxl_mem_raw_command_allowed(send_cmd->raw.opcode))
414 		return -EPERM;
415 
416 	dev_WARN_ONCE(cxl_mbox->host, true, "raw command path used\n");
417 
418 	*mem_cmd = (struct cxl_mem_command) {
419 		.info = {
420 			.id = CXL_MEM_COMMAND_ID_RAW,
421 			.size_in = send_cmd->in.size,
422 			.size_out = send_cmd->out.size,
423 		},
424 		.opcode = send_cmd->raw.opcode
425 	};
426 
427 	return 0;
428 }
429 
cxl_to_mem_cmd(struct cxl_mem_command * mem_cmd,const struct cxl_send_command * send_cmd,struct cxl_mailbox * cxl_mbox)430 static int cxl_to_mem_cmd(struct cxl_mem_command *mem_cmd,
431 			  const struct cxl_send_command *send_cmd,
432 			  struct cxl_mailbox *cxl_mbox)
433 {
434 	struct cxl_mem_command *c = &cxl_mem_commands[send_cmd->id];
435 	const struct cxl_command_info *info = &c->info;
436 
437 	if (send_cmd->flags & ~CXL_MEM_COMMAND_FLAG_MASK)
438 		return -EINVAL;
439 
440 	if (send_cmd->rsvd)
441 		return -EINVAL;
442 
443 	if (send_cmd->in.rsvd || send_cmd->out.rsvd)
444 		return -EINVAL;
445 
446 	/* Check that the command is enabled for hardware */
447 	if (!test_bit(info->id, cxl_mbox->enabled_cmds))
448 		return -ENOTTY;
449 
450 	/* Check that the command is not claimed for exclusive kernel use */
451 	if (test_bit(info->id, cxl_mbox->exclusive_cmds))
452 		return -EBUSY;
453 
454 	/* Check the input buffer is the expected size */
455 	if ((info->size_in != CXL_VARIABLE_PAYLOAD) &&
456 	    (info->size_in != send_cmd->in.size))
457 		return -ENOMEM;
458 
459 	/* Check the output buffer is at least large enough */
460 	if ((info->size_out != CXL_VARIABLE_PAYLOAD) &&
461 	    (send_cmd->out.size < info->size_out))
462 		return -ENOMEM;
463 
464 	*mem_cmd = (struct cxl_mem_command) {
465 		.info = {
466 			.id = info->id,
467 			.flags = info->flags,
468 			.size_in = send_cmd->in.size,
469 			.size_out = send_cmd->out.size,
470 		},
471 		.opcode = c->opcode
472 	};
473 
474 	return 0;
475 }
476 
477 /**
478  * cxl_validate_cmd_from_user() - Check fields for CXL_MEM_SEND_COMMAND.
479  * @mbox_cmd: Sanitized and populated &struct cxl_mbox_cmd.
480  * @cxl_mbox: CXL mailbox context
481  * @send_cmd: &struct cxl_send_command copied in from userspace.
482  *
483  * Return:
484  *  * %0	- @out_cmd is ready to send.
485  *  * %-ENOTTY	- Invalid command specified.
486  *  * %-EINVAL	- Reserved fields or invalid values were used.
487  *  * %-ENOMEM	- Input or output buffer wasn't sized properly.
488  *  * %-EPERM	- Attempted to use a protected command.
489  *  * %-EBUSY	- Kernel has claimed exclusive access to this opcode
490  *
491  * The result of this command is a fully validated command in @mbox_cmd that is
492  * safe to send to the hardware.
493  */
cxl_validate_cmd_from_user(struct cxl_mbox_cmd * mbox_cmd,struct cxl_mailbox * cxl_mbox,const struct cxl_send_command * send_cmd)494 static int cxl_validate_cmd_from_user(struct cxl_mbox_cmd *mbox_cmd,
495 				      struct cxl_mailbox *cxl_mbox,
496 				      const struct cxl_send_command *send_cmd)
497 {
498 	struct cxl_mem_command mem_cmd;
499 	int rc;
500 
501 	if (send_cmd->id == 0 || send_cmd->id >= CXL_MEM_COMMAND_ID_MAX)
502 		return -ENOTTY;
503 
504 	/*
505 	 * The user can never specify an input payload larger than what hardware
506 	 * supports, but output can be arbitrarily large (simply write out as
507 	 * much data as the hardware provides).
508 	 */
509 	if (send_cmd->in.size > cxl_mbox->payload_size)
510 		return -EINVAL;
511 
512 	/* Sanitize and construct a cxl_mem_command */
513 	if (send_cmd->id == CXL_MEM_COMMAND_ID_RAW)
514 		rc = cxl_to_mem_cmd_raw(&mem_cmd, send_cmd, cxl_mbox);
515 	else
516 		rc = cxl_to_mem_cmd(&mem_cmd, send_cmd, cxl_mbox);
517 
518 	if (rc)
519 		return rc;
520 
521 	/* Sanitize and construct a cxl_mbox_cmd */
522 	return cxl_mbox_cmd_ctor(mbox_cmd, cxl_mbox, mem_cmd.opcode,
523 				 mem_cmd.info.size_in, mem_cmd.info.size_out,
524 				 send_cmd->in.payload);
525 }
526 
cxl_query_cmd(struct cxl_mailbox * cxl_mbox,struct cxl_mem_query_commands __user * q)527 int cxl_query_cmd(struct cxl_mailbox *cxl_mbox,
528 		  struct cxl_mem_query_commands __user *q)
529 {
530 	struct device *dev = cxl_mbox->host;
531 	struct cxl_mem_command *cmd;
532 	u32 n_commands;
533 	int j = 0;
534 
535 	dev_dbg(dev, "Query IOCTL\n");
536 
537 	if (get_user(n_commands, &q->n_commands))
538 		return -EFAULT;
539 
540 	/* returns the total number if 0 elements are requested. */
541 	if (n_commands == 0)
542 		return put_user(ARRAY_SIZE(cxl_mem_commands), &q->n_commands);
543 
544 	/*
545 	 * otherwise, return min(n_commands, total commands) cxl_command_info
546 	 * structures.
547 	 */
548 	cxl_for_each_cmd(cmd) {
549 		struct cxl_command_info info = cmd->info;
550 
551 		if (test_bit(info.id, cxl_mbox->enabled_cmds))
552 			info.flags |= CXL_MEM_COMMAND_FLAG_ENABLED;
553 		if (test_bit(info.id, cxl_mbox->exclusive_cmds))
554 			info.flags |= CXL_MEM_COMMAND_FLAG_EXCLUSIVE;
555 
556 		if (copy_to_user(&q->commands[j++], &info, sizeof(info)))
557 			return -EFAULT;
558 
559 		if (j == n_commands)
560 			break;
561 	}
562 
563 	return 0;
564 }
565 
566 /**
567  * handle_mailbox_cmd_from_user() - Dispatch a mailbox command for userspace.
568  * @cxl_mbox: The mailbox context for the operation.
569  * @mbox_cmd: The validated mailbox command.
570  * @out_payload: Pointer to userspace's output payload.
571  * @size_out: (Input) Max payload size to copy out.
572  *            (Output) Payload size hardware generated.
573  * @retval: Hardware generated return code from the operation.
574  *
575  * Return:
576  *  * %0	- Mailbox transaction succeeded. This implies the mailbox
577  *		  protocol completed successfully not that the operation itself
578  *		  was successful.
579  *  * %-ENOMEM  - Couldn't allocate a bounce buffer.
580  *  * %-EFAULT	- Something happened with copy_to/from_user.
581  *  * %-EINTR	- Mailbox acquisition interrupted.
582  *  * %-EXXX	- Transaction level failures.
583  *
584  * Dispatches a mailbox command on behalf of a userspace request.
585  * The output payload is copied to userspace.
586  *
587  * See cxl_send_cmd().
588  */
handle_mailbox_cmd_from_user(struct cxl_mailbox * cxl_mbox,struct cxl_mbox_cmd * mbox_cmd,u64 out_payload,s32 * size_out,u32 * retval)589 static int handle_mailbox_cmd_from_user(struct cxl_mailbox *cxl_mbox,
590 					struct cxl_mbox_cmd *mbox_cmd,
591 					u64 out_payload, s32 *size_out,
592 					u32 *retval)
593 {
594 	struct device *dev = cxl_mbox->host;
595 	int rc;
596 
597 	dev_dbg(dev,
598 		"Submitting %s command for user\n"
599 		"\topcode: %x\n"
600 		"\tsize: %zx\n",
601 		cxl_mem_opcode_to_name(mbox_cmd->opcode),
602 		mbox_cmd->opcode, mbox_cmd->size_in);
603 
604 	rc = cxl_mbox->mbox_send(cxl_mbox, mbox_cmd);
605 	if (rc)
606 		goto out;
607 
608 	/*
609 	 * @size_out contains the max size that's allowed to be written back out
610 	 * to userspace. While the payload may have written more output than
611 	 * this it will have to be ignored.
612 	 */
613 	if (mbox_cmd->size_out) {
614 		dev_WARN_ONCE(dev, mbox_cmd->size_out > *size_out,
615 			      "Invalid return size\n");
616 		if (copy_to_user(u64_to_user_ptr(out_payload),
617 				 mbox_cmd->payload_out, mbox_cmd->size_out)) {
618 			rc = -EFAULT;
619 			goto out;
620 		}
621 	}
622 
623 	*size_out = mbox_cmd->size_out;
624 	*retval = mbox_cmd->return_code;
625 
626 out:
627 	cxl_mbox_cmd_dtor(mbox_cmd);
628 	return rc;
629 }
630 
cxl_send_cmd(struct cxl_mailbox * cxl_mbox,struct cxl_send_command __user * s)631 int cxl_send_cmd(struct cxl_mailbox *cxl_mbox, struct cxl_send_command __user *s)
632 {
633 	struct device *dev = cxl_mbox->host;
634 	struct cxl_send_command send;
635 	struct cxl_mbox_cmd mbox_cmd;
636 	int rc;
637 
638 	dev_dbg(dev, "Send IOCTL\n");
639 
640 	if (copy_from_user(&send, s, sizeof(send)))
641 		return -EFAULT;
642 
643 	rc = cxl_validate_cmd_from_user(&mbox_cmd, cxl_mbox, &send);
644 	if (rc)
645 		return rc;
646 
647 	rc = handle_mailbox_cmd_from_user(cxl_mbox, &mbox_cmd, send.out.payload,
648 					  &send.out.size, &send.retval);
649 	if (rc)
650 		return rc;
651 
652 	if (copy_to_user(s, &send, sizeof(send)))
653 		return -EFAULT;
654 
655 	return 0;
656 }
657 
cxl_xfer_log(struct cxl_memdev_state * mds,uuid_t * uuid,u32 * size,u8 * out)658 static int cxl_xfer_log(struct cxl_memdev_state *mds, uuid_t *uuid,
659 			u32 *size, u8 *out)
660 {
661 	struct cxl_mailbox *cxl_mbox = &mds->cxlds.cxl_mbox;
662 	u32 remaining = *size;
663 	u32 offset = 0;
664 
665 	while (remaining) {
666 		u32 xfer_size = min_t(u32, remaining, cxl_mbox->payload_size);
667 		struct cxl_mbox_cmd mbox_cmd;
668 		struct cxl_mbox_get_log log;
669 		int rc;
670 
671 		log = (struct cxl_mbox_get_log) {
672 			.uuid = *uuid,
673 			.offset = cpu_to_le32(offset),
674 			.length = cpu_to_le32(xfer_size),
675 		};
676 
677 		mbox_cmd = (struct cxl_mbox_cmd) {
678 			.opcode = CXL_MBOX_OP_GET_LOG,
679 			.size_in = sizeof(log),
680 			.payload_in = &log,
681 			.size_out = xfer_size,
682 			.payload_out = out,
683 		};
684 
685 		rc = cxl_internal_send_cmd(cxl_mbox, &mbox_cmd);
686 
687 		/*
688 		 * The output payload length that indicates the number
689 		 * of valid bytes can be smaller than the Log buffer
690 		 * size.
691 		 */
692 		if (rc == -EIO && mbox_cmd.size_out < xfer_size) {
693 			offset += mbox_cmd.size_out;
694 			break;
695 		}
696 
697 		if (rc < 0)
698 			return rc;
699 
700 		out += xfer_size;
701 		remaining -= xfer_size;
702 		offset += xfer_size;
703 	}
704 
705 	*size = offset;
706 
707 	return 0;
708 }
709 
check_features_opcodes(u16 opcode,int * ro_cmds,int * wr_cmds)710 static int check_features_opcodes(u16 opcode, int *ro_cmds, int *wr_cmds)
711 {
712 	switch (opcode) {
713 	case CXL_MBOX_OP_GET_SUPPORTED_FEATURES:
714 	case CXL_MBOX_OP_GET_FEATURE:
715 		(*ro_cmds)++;
716 		return 1;
717 	case CXL_MBOX_OP_SET_FEATURE:
718 		(*wr_cmds)++;
719 		return 1;
720 	default:
721 		return 0;
722 	}
723 }
724 
725 /* 'Get Supported Features' and 'Get Feature' */
726 #define MAX_FEATURES_READ_CMDS	2
set_features_cap(struct cxl_mailbox * cxl_mbox,int ro_cmds,int wr_cmds)727 static void set_features_cap(struct cxl_mailbox *cxl_mbox,
728 			     int ro_cmds, int wr_cmds)
729 {
730 	/* Setting up Features capability while walking the CEL */
731 	if (ro_cmds == MAX_FEATURES_READ_CMDS) {
732 		if (wr_cmds)
733 			cxl_mbox->feat_cap = CXL_FEATURES_RW;
734 		else
735 			cxl_mbox->feat_cap = CXL_FEATURES_RO;
736 	}
737 }
738 
739 /**
740  * cxl_walk_cel() - Walk through the Command Effects Log.
741  * @mds: The driver data for the operation
742  * @size: Length of the Command Effects Log.
743  * @cel: CEL
744  *
745  * Iterate over each entry in the CEL and determine if the driver supports the
746  * command. If so, the command is enabled for the device and can be used later.
747  */
cxl_walk_cel(struct cxl_memdev_state * mds,size_t size,u8 * cel)748 static void cxl_walk_cel(struct cxl_memdev_state *mds, size_t size, u8 *cel)
749 {
750 	struct cxl_mailbox *cxl_mbox = &mds->cxlds.cxl_mbox;
751 	struct cxl_cel_entry *cel_entry;
752 	const int cel_entries = size / sizeof(*cel_entry);
753 	struct device *dev = mds->cxlds.dev;
754 	int i, ro_cmds = 0, wr_cmds = 0;
755 
756 	cel_entry = (struct cxl_cel_entry *) cel;
757 
758 	for (i = 0; i < cel_entries; i++) {
759 		u16 opcode = le16_to_cpu(cel_entry[i].opcode);
760 		struct cxl_mem_command *cmd = cxl_mem_find_command(opcode);
761 		int enabled = 0;
762 
763 		if (cmd) {
764 			set_bit(cmd->info.id, cxl_mbox->enabled_cmds);
765 			enabled++;
766 		}
767 
768 		enabled += check_features_opcodes(opcode, &ro_cmds,
769 						  &wr_cmds);
770 
771 		if (cxl_is_poison_command(opcode)) {
772 			cxl_set_poison_cmd_enabled(&mds->poison, opcode);
773 			enabled++;
774 		}
775 
776 		if (cxl_is_security_command(opcode)) {
777 			cxl_set_security_cmd_enabled(&mds->security, opcode);
778 			enabled++;
779 		}
780 
781 		dev_dbg(dev, "Opcode 0x%04x %s\n", opcode,
782 			enabled ? "enabled" : "unsupported by driver");
783 	}
784 
785 	set_features_cap(cxl_mbox, ro_cmds, wr_cmds);
786 }
787 
cxl_get_gsl(struct cxl_memdev_state * mds)788 static struct cxl_mbox_get_supported_logs *cxl_get_gsl(struct cxl_memdev_state *mds)
789 {
790 	struct cxl_mailbox *cxl_mbox = &mds->cxlds.cxl_mbox;
791 	struct cxl_mbox_get_supported_logs *ret;
792 	struct cxl_mbox_cmd mbox_cmd;
793 	int rc;
794 
795 	ret = kvmalloc(cxl_mbox->payload_size, GFP_KERNEL);
796 	if (!ret)
797 		return ERR_PTR(-ENOMEM);
798 
799 	mbox_cmd = (struct cxl_mbox_cmd) {
800 		.opcode = CXL_MBOX_OP_GET_SUPPORTED_LOGS,
801 		.size_out = cxl_mbox->payload_size,
802 		.payload_out = ret,
803 		/* At least the record number field must be valid */
804 		.min_out = 2,
805 	};
806 	rc = cxl_internal_send_cmd(cxl_mbox, &mbox_cmd);
807 	if (rc < 0) {
808 		kvfree(ret);
809 		return ERR_PTR(rc);
810 	}
811 
812 
813 	return ret;
814 }
815 
816 enum {
817 	CEL_UUID,
818 	VENDOR_DEBUG_UUID,
819 };
820 
821 /* See CXL 2.0 Table 170. Get Log Input Payload */
822 static const uuid_t log_uuid[] = {
823 	[CEL_UUID] = DEFINE_CXL_CEL_UUID,
824 	[VENDOR_DEBUG_UUID] = DEFINE_CXL_VENDOR_DEBUG_UUID,
825 };
826 
827 /**
828  * cxl_enumerate_cmds() - Enumerate commands for a device.
829  * @mds: The driver data for the operation
830  *
831  * Returns 0 if enumerate completed successfully.
832  *
833  * CXL devices have optional support for certain commands. This function will
834  * determine the set of supported commands for the hardware and update the
835  * enabled_cmds bitmap in the @mds.
836  */
cxl_enumerate_cmds(struct cxl_memdev_state * mds)837 int cxl_enumerate_cmds(struct cxl_memdev_state *mds)
838 {
839 	struct cxl_mailbox *cxl_mbox = &mds->cxlds.cxl_mbox;
840 	struct cxl_mbox_get_supported_logs *gsl;
841 	struct device *dev = mds->cxlds.dev;
842 	struct cxl_mem_command *cmd;
843 	int i, rc;
844 
845 	gsl = cxl_get_gsl(mds);
846 	if (IS_ERR(gsl))
847 		return PTR_ERR(gsl);
848 
849 	rc = -ENOENT;
850 	for (i = 0; i < le16_to_cpu(gsl->entries); i++) {
851 		u32 size = le32_to_cpu(gsl->entry[i].size);
852 		uuid_t uuid = gsl->entry[i].uuid;
853 		u8 *log;
854 
855 		dev_dbg(dev, "Found LOG type %pU of size %d", &uuid, size);
856 
857 		if (!uuid_equal(&uuid, &log_uuid[CEL_UUID]))
858 			continue;
859 
860 		log = kvmalloc(size, GFP_KERNEL);
861 		if (!log) {
862 			rc = -ENOMEM;
863 			goto out;
864 		}
865 
866 		rc = cxl_xfer_log(mds, &uuid, &size, log);
867 		if (rc) {
868 			kvfree(log);
869 			goto out;
870 		}
871 
872 		cxl_walk_cel(mds, size, log);
873 		kvfree(log);
874 
875 		/* In case CEL was bogus, enable some default commands. */
876 		cxl_for_each_cmd(cmd)
877 			if (cmd->flags & CXL_CMD_FLAG_FORCE_ENABLE)
878 				set_bit(cmd->info.id, cxl_mbox->enabled_cmds);
879 
880 		/* Found the required CEL */
881 		rc = 0;
882 	}
883 out:
884 	kvfree(gsl);
885 	return rc;
886 }
887 EXPORT_SYMBOL_NS_GPL(cxl_enumerate_cmds, "CXL");
888 
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)889 void cxl_event_trace_record(const struct cxl_memdev *cxlmd,
890 			    enum cxl_event_log_type type,
891 			    enum cxl_event_type event_type,
892 			    const uuid_t *uuid, union cxl_event *evt)
893 {
894 	if (event_type == CXL_CPER_EVENT_MEM_MODULE) {
895 		trace_cxl_memory_module(cxlmd, type, &evt->mem_module);
896 		return;
897 	}
898 	if (event_type == CXL_CPER_EVENT_GENERIC) {
899 		trace_cxl_generic_event(cxlmd, type, uuid, &evt->generic);
900 		return;
901 	}
902 	if (event_type == CXL_CPER_EVENT_MEM_SPARING) {
903 		trace_cxl_memory_sparing(cxlmd, type, &evt->mem_sparing);
904 		return;
905 	}
906 
907 	if (trace_cxl_general_media_enabled() || trace_cxl_dram_enabled()) {
908 		u64 dpa, hpa = ULLONG_MAX, hpa_alias = ULLONG_MAX;
909 		struct cxl_region *cxlr;
910 
911 		/*
912 		 * These trace points are annotated with HPA and region
913 		 * translations. Take topology mutation locks and lookup
914 		 * { HPA, REGION } from { DPA, MEMDEV } in the event record.
915 		 */
916 		guard(rwsem_read)(&cxl_rwsem.region);
917 		guard(rwsem_read)(&cxl_rwsem.dpa);
918 
919 		dpa = le64_to_cpu(evt->media_hdr.phys_addr) & CXL_DPA_MASK;
920 		cxlr = cxl_dpa_to_region(cxlmd, dpa);
921 		if (cxlr) {
922 			u64 cache_size = cxlr->params.cache_size;
923 
924 			hpa = cxl_dpa_to_hpa(cxlr, cxlmd, dpa);
925 			if (cache_size)
926 				hpa_alias = hpa - cache_size;
927 		}
928 
929 		if (event_type == CXL_CPER_EVENT_GEN_MEDIA) {
930 			if (cxl_store_rec_gen_media((struct cxl_memdev *)cxlmd, evt))
931 				dev_dbg(&cxlmd->dev, "CXL store rec_gen_media failed\n");
932 
933 			if (evt->gen_media.media_hdr.descriptor &
934 			    CXL_GMER_EVT_DESC_THRESHOLD_EVENT)
935 				WARN_ON_ONCE((evt->gen_media.media_hdr.type &
936 					      CXL_GMER_MEM_EVT_TYPE_AP_CME_COUNTER_EXPIRE) &&
937 					     !get_unaligned_le24(evt->gen_media.cme_count));
938 			else
939 				WARN_ON_ONCE(evt->gen_media.media_hdr.type &
940 					     CXL_GMER_MEM_EVT_TYPE_AP_CME_COUNTER_EXPIRE);
941 
942 			trace_cxl_general_media(cxlmd, type, cxlr, hpa,
943 						hpa_alias, &evt->gen_media);
944 		} else if (event_type == CXL_CPER_EVENT_DRAM) {
945 			if (cxl_store_rec_dram((struct cxl_memdev *)cxlmd, evt))
946 				dev_dbg(&cxlmd->dev, "CXL store rec_dram failed\n");
947 
948 			if (evt->dram.media_hdr.descriptor &
949 			    CXL_GMER_EVT_DESC_THRESHOLD_EVENT)
950 				WARN_ON_ONCE((evt->dram.media_hdr.type &
951 					      CXL_DER_MEM_EVT_TYPE_AP_CME_COUNTER_EXPIRE) &&
952 					     !get_unaligned_le24(evt->dram.cvme_count));
953 			else
954 				WARN_ON_ONCE(evt->dram.media_hdr.type &
955 					     CXL_DER_MEM_EVT_TYPE_AP_CME_COUNTER_EXPIRE);
956 
957 			trace_cxl_dram(cxlmd, type, cxlr, hpa, hpa_alias,
958 				       &evt->dram);
959 		}
960 	}
961 }
962 EXPORT_SYMBOL_NS_GPL(cxl_event_trace_record, "CXL");
963 
__cxl_event_trace_record(const struct cxl_memdev * cxlmd,enum cxl_event_log_type type,struct cxl_event_record_raw * record)964 static void __cxl_event_trace_record(const struct cxl_memdev *cxlmd,
965 				     enum cxl_event_log_type type,
966 				     struct cxl_event_record_raw *record)
967 {
968 	enum cxl_event_type ev_type = CXL_CPER_EVENT_GENERIC;
969 	const uuid_t *uuid = &record->id;
970 
971 	if (uuid_equal(uuid, &CXL_EVENT_GEN_MEDIA_UUID))
972 		ev_type = CXL_CPER_EVENT_GEN_MEDIA;
973 	else if (uuid_equal(uuid, &CXL_EVENT_DRAM_UUID))
974 		ev_type = CXL_CPER_EVENT_DRAM;
975 	else if (uuid_equal(uuid, &CXL_EVENT_MEM_MODULE_UUID))
976 		ev_type = CXL_CPER_EVENT_MEM_MODULE;
977 	else if (uuid_equal(uuid, &CXL_EVENT_MEM_SPARING_UUID))
978 		ev_type = CXL_CPER_EVENT_MEM_SPARING;
979 
980 	cxl_event_trace_record(cxlmd, type, ev_type, uuid, &record->event);
981 }
982 
cxl_clear_event_record(struct cxl_memdev_state * mds,enum cxl_event_log_type log,struct cxl_get_event_payload * get_pl)983 static int cxl_clear_event_record(struct cxl_memdev_state *mds,
984 				  enum cxl_event_log_type log,
985 				  struct cxl_get_event_payload *get_pl)
986 {
987 	struct cxl_mailbox *cxl_mbox = &mds->cxlds.cxl_mbox;
988 	struct cxl_mbox_clear_event_payload *payload;
989 	u16 total = le16_to_cpu(get_pl->record_count);
990 	u8 max_handles = CXL_CLEAR_EVENT_MAX_HANDLES;
991 	size_t pl_size = struct_size(payload, handles, max_handles);
992 	struct cxl_mbox_cmd mbox_cmd;
993 	u16 cnt;
994 	int rc = 0;
995 	int i;
996 
997 	/* Payload size may limit the max handles */
998 	if (pl_size > cxl_mbox->payload_size) {
999 		max_handles = (cxl_mbox->payload_size - sizeof(*payload)) /
1000 			      sizeof(__le16);
1001 		pl_size = struct_size(payload, handles, max_handles);
1002 	}
1003 
1004 	payload = kvzalloc(pl_size, GFP_KERNEL);
1005 	if (!payload)
1006 		return -ENOMEM;
1007 
1008 	*payload = (struct cxl_mbox_clear_event_payload) {
1009 		.event_log = log,
1010 	};
1011 
1012 	mbox_cmd = (struct cxl_mbox_cmd) {
1013 		.opcode = CXL_MBOX_OP_CLEAR_EVENT_RECORD,
1014 		.payload_in = payload,
1015 		.size_in = pl_size,
1016 	};
1017 
1018 	/*
1019 	 * Clear Event Records uses u8 for the handle cnt while Get Event
1020 	 * Record can return up to 0xffff records.
1021 	 */
1022 	i = 0;
1023 	for (cnt = 0; cnt < total; cnt++) {
1024 		struct cxl_event_record_raw *raw = &get_pl->records[cnt];
1025 		struct cxl_event_generic *gen = &raw->event.generic;
1026 
1027 		payload->handles[i++] = gen->hdr.handle;
1028 		dev_dbg(mds->cxlds.dev, "Event log '%d': Clearing %u\n", log,
1029 			le16_to_cpu(payload->handles[i - 1]));
1030 
1031 		if (i == max_handles) {
1032 			payload->nr_recs = i;
1033 			rc = cxl_internal_send_cmd(cxl_mbox, &mbox_cmd);
1034 			if (rc)
1035 				goto free_pl;
1036 			i = 0;
1037 		}
1038 	}
1039 
1040 	/* Clear what is left if any */
1041 	if (i) {
1042 		payload->nr_recs = i;
1043 		mbox_cmd.size_in = struct_size(payload, handles, i);
1044 		rc = cxl_internal_send_cmd(cxl_mbox, &mbox_cmd);
1045 		if (rc)
1046 			goto free_pl;
1047 	}
1048 
1049 free_pl:
1050 	kvfree(payload);
1051 	return rc;
1052 }
1053 
cxl_mem_get_records_log(struct cxl_memdev_state * mds,enum cxl_event_log_type type)1054 static void cxl_mem_get_records_log(struct cxl_memdev_state *mds,
1055 				    enum cxl_event_log_type type)
1056 {
1057 	struct cxl_mailbox *cxl_mbox = &mds->cxlds.cxl_mbox;
1058 	struct cxl_memdev *cxlmd = mds->cxlds.cxlmd;
1059 	struct device *dev = mds->cxlds.dev;
1060 	struct cxl_get_event_payload *payload;
1061 	u8 log_type = type;
1062 	u16 nr_rec;
1063 
1064 	mutex_lock(&mds->event.log_lock);
1065 	payload = mds->event.buf;
1066 
1067 	do {
1068 		int rc, i;
1069 		struct cxl_mbox_cmd mbox_cmd = (struct cxl_mbox_cmd) {
1070 			.opcode = CXL_MBOX_OP_GET_EVENT_RECORD,
1071 			.payload_in = &log_type,
1072 			.size_in = sizeof(log_type),
1073 			.payload_out = payload,
1074 			.size_out = cxl_mbox->payload_size,
1075 			.min_out = struct_size(payload, records, 0),
1076 		};
1077 
1078 		rc = cxl_internal_send_cmd(cxl_mbox, &mbox_cmd);
1079 		if (rc) {
1080 			dev_err_ratelimited(dev,
1081 				"Event log '%d': Failed to query event records : %d",
1082 				type, rc);
1083 			break;
1084 		}
1085 
1086 		nr_rec = le16_to_cpu(payload->record_count);
1087 		if (!nr_rec)
1088 			break;
1089 
1090 		for (i = 0; i < nr_rec; i++)
1091 			__cxl_event_trace_record(cxlmd, type,
1092 						 &payload->records[i]);
1093 
1094 		if (payload->flags & CXL_GET_EVENT_FLAG_OVERFLOW)
1095 			trace_cxl_overflow(cxlmd, type, payload);
1096 
1097 		rc = cxl_clear_event_record(mds, type, payload);
1098 		if (rc) {
1099 			dev_err_ratelimited(dev,
1100 				"Event log '%d': Failed to clear events : %d",
1101 				type, rc);
1102 			break;
1103 		}
1104 	} while (nr_rec);
1105 
1106 	mutex_unlock(&mds->event.log_lock);
1107 }
1108 
1109 /**
1110  * cxl_mem_get_event_records - Get Event Records from the device
1111  * @mds: The driver data for the operation
1112  * @status: Event Status register value identifying which events are available.
1113  *
1114  * Retrieve all event records available on the device, report them as trace
1115  * events, and clear them.
1116  *
1117  * See CXL rev 3.0 @8.2.9.2.2 Get Event Records
1118  * See CXL rev 3.0 @8.2.9.2.3 Clear Event Records
1119  */
cxl_mem_get_event_records(struct cxl_memdev_state * mds,u32 status)1120 void cxl_mem_get_event_records(struct cxl_memdev_state *mds, u32 status)
1121 {
1122 	dev_dbg(mds->cxlds.dev, "Reading event logs: %x\n", status);
1123 
1124 	if (status & CXLDEV_EVENT_STATUS_FATAL)
1125 		cxl_mem_get_records_log(mds, CXL_EVENT_TYPE_FATAL);
1126 	if (status & CXLDEV_EVENT_STATUS_FAIL)
1127 		cxl_mem_get_records_log(mds, CXL_EVENT_TYPE_FAIL);
1128 	if (status & CXLDEV_EVENT_STATUS_WARN)
1129 		cxl_mem_get_records_log(mds, CXL_EVENT_TYPE_WARN);
1130 	if (status & CXLDEV_EVENT_STATUS_INFO)
1131 		cxl_mem_get_records_log(mds, CXL_EVENT_TYPE_INFO);
1132 }
1133 EXPORT_SYMBOL_NS_GPL(cxl_mem_get_event_records, "CXL");
1134 
1135 /**
1136  * cxl_mem_get_partition_info - Get partition info
1137  * @mds: The driver data for the operation
1138  *
1139  * Retrieve the current partition info for the device specified.  The active
1140  * values are the current capacity in bytes.  If not 0, the 'next' values are
1141  * the pending values, in bytes, which take affect on next cold reset.
1142  *
1143  * Return: 0 if no error: or the result of the mailbox command.
1144  *
1145  * See CXL @8.2.9.5.2.1 Get Partition Info
1146  */
cxl_mem_get_partition_info(struct cxl_memdev_state * mds)1147 static int cxl_mem_get_partition_info(struct cxl_memdev_state *mds)
1148 {
1149 	struct cxl_mailbox *cxl_mbox = &mds->cxlds.cxl_mbox;
1150 	struct cxl_mbox_get_partition_info pi;
1151 	struct cxl_mbox_cmd mbox_cmd;
1152 	int rc;
1153 
1154 	mbox_cmd = (struct cxl_mbox_cmd) {
1155 		.opcode = CXL_MBOX_OP_GET_PARTITION_INFO,
1156 		.size_out = sizeof(pi),
1157 		.payload_out = &pi,
1158 	};
1159 	rc = cxl_internal_send_cmd(cxl_mbox, &mbox_cmd);
1160 	if (rc)
1161 		return rc;
1162 
1163 	mds->active_volatile_bytes =
1164 		le64_to_cpu(pi.active_volatile_cap) * CXL_CAPACITY_MULTIPLIER;
1165 	mds->active_persistent_bytes =
1166 		le64_to_cpu(pi.active_persistent_cap) * CXL_CAPACITY_MULTIPLIER;
1167 
1168 	return 0;
1169 }
1170 
1171 /**
1172  * cxl_dev_state_identify() - Send the IDENTIFY command to the device.
1173  * @mds: The driver data for the operation
1174  *
1175  * Return: 0 if identify was executed successfully or media not ready.
1176  *
1177  * This will dispatch the identify command to the device and on success populate
1178  * structures to be exported to sysfs.
1179  */
cxl_dev_state_identify(struct cxl_memdev_state * mds)1180 int cxl_dev_state_identify(struct cxl_memdev_state *mds)
1181 {
1182 	struct cxl_mailbox *cxl_mbox = &mds->cxlds.cxl_mbox;
1183 	/* See CXL 2.0 Table 175 Identify Memory Device Output Payload */
1184 	struct cxl_mbox_identify id;
1185 	struct cxl_mbox_cmd mbox_cmd;
1186 	u32 val;
1187 	int rc;
1188 
1189 	if (!mds->cxlds.media_ready)
1190 		return 0;
1191 
1192 	mbox_cmd = (struct cxl_mbox_cmd) {
1193 		.opcode = CXL_MBOX_OP_IDENTIFY,
1194 		.size_out = sizeof(id),
1195 		.payload_out = &id,
1196 	};
1197 	rc = cxl_internal_send_cmd(cxl_mbox, &mbox_cmd);
1198 	if (rc < 0)
1199 		return rc;
1200 
1201 	mds->total_bytes =
1202 		le64_to_cpu(id.total_capacity) * CXL_CAPACITY_MULTIPLIER;
1203 	mds->volatile_only_bytes =
1204 		le64_to_cpu(id.volatile_capacity) * CXL_CAPACITY_MULTIPLIER;
1205 	mds->persistent_only_bytes =
1206 		le64_to_cpu(id.persistent_capacity) * CXL_CAPACITY_MULTIPLIER;
1207 	mds->partition_align_bytes =
1208 		le64_to_cpu(id.partition_align) * CXL_CAPACITY_MULTIPLIER;
1209 
1210 	mds->lsa_size = le32_to_cpu(id.lsa_size);
1211 	memcpy(mds->firmware_version, id.fw_revision,
1212 	       sizeof(id.fw_revision));
1213 
1214 	if (test_bit(CXL_POISON_ENABLED_LIST, mds->poison.enabled_cmds)) {
1215 		val = get_unaligned_le24(id.poison_list_max_mer);
1216 		mds->poison.max_errors = min_t(u32, val, CXL_POISON_LIST_MAX);
1217 	}
1218 
1219 	return 0;
1220 }
1221 EXPORT_SYMBOL_NS_GPL(cxl_dev_state_identify, "CXL");
1222 
__cxl_mem_sanitize(struct cxl_memdev_state * mds,u16 cmd)1223 static int __cxl_mem_sanitize(struct cxl_memdev_state *mds, u16 cmd)
1224 {
1225 	struct cxl_mailbox *cxl_mbox = &mds->cxlds.cxl_mbox;
1226 	int rc;
1227 	u32 sec_out = 0;
1228 	struct cxl_get_security_output {
1229 		__le32 flags;
1230 	} out;
1231 	struct cxl_mbox_cmd sec_cmd = {
1232 		.opcode = CXL_MBOX_OP_GET_SECURITY_STATE,
1233 		.payload_out = &out,
1234 		.size_out = sizeof(out),
1235 	};
1236 	struct cxl_mbox_cmd mbox_cmd = { .opcode = cmd };
1237 
1238 	if (cmd != CXL_MBOX_OP_SANITIZE && cmd != CXL_MBOX_OP_SECURE_ERASE)
1239 		return -EINVAL;
1240 
1241 	rc = cxl_internal_send_cmd(cxl_mbox, &sec_cmd);
1242 	if (rc < 0) {
1243 		dev_err(cxl_mbox->host, "Failed to get security state : %d", rc);
1244 		return rc;
1245 	}
1246 
1247 	/*
1248 	 * Prior to using these commands, any security applied to
1249 	 * the user data areas of the device shall be DISABLED (or
1250 	 * UNLOCKED for secure erase case).
1251 	 */
1252 	sec_out = le32_to_cpu(out.flags);
1253 	if (sec_out & CXL_PMEM_SEC_STATE_USER_PASS_SET)
1254 		return -EINVAL;
1255 
1256 	if (cmd == CXL_MBOX_OP_SECURE_ERASE &&
1257 	    sec_out & CXL_PMEM_SEC_STATE_LOCKED)
1258 		return -EINVAL;
1259 
1260 	rc = cxl_internal_send_cmd(cxl_mbox, &mbox_cmd);
1261 	if (rc < 0) {
1262 		dev_err(cxl_mbox->host, "Failed to sanitize device : %d", rc);
1263 		return rc;
1264 	}
1265 
1266 	return 0;
1267 }
1268 
1269 
1270 /**
1271  * cxl_mem_sanitize() - Send a sanitization command to the device.
1272  * @cxlmd: The device for the operation
1273  * @cmd: The specific sanitization command opcode
1274  *
1275  * Return: 0 if the command was executed successfully, regardless of
1276  * whether or not the actual security operation is done in the background,
1277  * such as for the Sanitize case.
1278  * Error return values can be the result of the mailbox command, -EINVAL
1279  * when security requirements are not met or invalid contexts, or -EBUSY
1280  * if the sanitize operation is already in flight.
1281  *
1282  * See CXL 3.0 @8.2.9.8.5.1 Sanitize and @8.2.9.8.5.2 Secure Erase.
1283  */
cxl_mem_sanitize(struct cxl_memdev * cxlmd,u16 cmd)1284 int cxl_mem_sanitize(struct cxl_memdev *cxlmd, u16 cmd)
1285 {
1286 	struct cxl_memdev_state *mds = to_cxl_memdev_state(cxlmd->cxlds);
1287 	struct cxl_port  *endpoint;
1288 
1289 	/* synchronize with cxl_mem_probe() and decoder write operations */
1290 	guard(device)(&cxlmd->dev);
1291 	endpoint = cxlmd->endpoint;
1292 	guard(rwsem_read)(&cxl_rwsem.region);
1293 	/*
1294 	 * Require an endpoint to be safe otherwise the driver can not
1295 	 * be sure that the device is unmapped.
1296 	 */
1297 	if (endpoint && cxl_num_decoders_committed(endpoint) == 0)
1298 		return __cxl_mem_sanitize(mds, cmd);
1299 
1300 	return -EBUSY;
1301 }
1302 
add_part(struct cxl_dpa_info * info,u64 start,u64 size,enum cxl_partition_mode mode)1303 static void add_part(struct cxl_dpa_info *info, u64 start, u64 size, enum cxl_partition_mode mode)
1304 {
1305 	int i = info->nr_partitions;
1306 
1307 	if (size == 0)
1308 		return;
1309 
1310 	info->part[i].range = (struct range) {
1311 		.start = start,
1312 		.end = start + size - 1,
1313 	};
1314 	info->part[i].mode = mode;
1315 	info->nr_partitions++;
1316 }
1317 
cxl_mem_dpa_fetch(struct cxl_memdev_state * mds,struct cxl_dpa_info * info)1318 int cxl_mem_dpa_fetch(struct cxl_memdev_state *mds, struct cxl_dpa_info *info)
1319 {
1320 	struct cxl_dev_state *cxlds = &mds->cxlds;
1321 	struct device *dev = cxlds->dev;
1322 	int rc;
1323 
1324 	if (!cxlds->media_ready) {
1325 		info->size = 0;
1326 		return 0;
1327 	}
1328 
1329 	info->size = mds->total_bytes;
1330 
1331 	if (mds->partition_align_bytes == 0) {
1332 		add_part(info, 0, mds->volatile_only_bytes, CXL_PARTMODE_RAM);
1333 		add_part(info, mds->volatile_only_bytes,
1334 			 mds->persistent_only_bytes, CXL_PARTMODE_PMEM);
1335 		return 0;
1336 	}
1337 
1338 	rc = cxl_mem_get_partition_info(mds);
1339 	if (rc) {
1340 		dev_err(dev, "Failed to query partition information\n");
1341 		return rc;
1342 	}
1343 
1344 	add_part(info, 0, mds->active_volatile_bytes, CXL_PARTMODE_RAM);
1345 	add_part(info, mds->active_volatile_bytes, mds->active_persistent_bytes,
1346 		 CXL_PARTMODE_PMEM);
1347 
1348 	return 0;
1349 }
1350 EXPORT_SYMBOL_NS_GPL(cxl_mem_dpa_fetch, "CXL");
1351 
cxl_get_dirty_count(struct cxl_memdev_state * mds,u32 * count)1352 int cxl_get_dirty_count(struct cxl_memdev_state *mds, u32 *count)
1353 {
1354 	struct cxl_mailbox *cxl_mbox = &mds->cxlds.cxl_mbox;
1355 	struct cxl_mbox_get_health_info_out hi;
1356 	struct cxl_mbox_cmd mbox_cmd;
1357 	int rc;
1358 
1359 	mbox_cmd = (struct cxl_mbox_cmd) {
1360 		.opcode = CXL_MBOX_OP_GET_HEALTH_INFO,
1361 		.size_out = sizeof(hi),
1362 		.payload_out = &hi,
1363 	};
1364 
1365 	rc = cxl_internal_send_cmd(cxl_mbox, &mbox_cmd);
1366 	if (!rc)
1367 		*count = le32_to_cpu(hi.dirty_shutdown_cnt);
1368 
1369 	return rc;
1370 }
1371 EXPORT_SYMBOL_NS_GPL(cxl_get_dirty_count, "CXL");
1372 
cxl_arm_dirty_shutdown(struct cxl_memdev_state * mds)1373 int cxl_arm_dirty_shutdown(struct cxl_memdev_state *mds)
1374 {
1375 	struct cxl_mailbox *cxl_mbox = &mds->cxlds.cxl_mbox;
1376 	struct cxl_mbox_cmd mbox_cmd;
1377 	struct cxl_mbox_set_shutdown_state_in in = {
1378 		.state = 1
1379 	};
1380 
1381 	mbox_cmd = (struct cxl_mbox_cmd) {
1382 		.opcode = CXL_MBOX_OP_SET_SHUTDOWN_STATE,
1383 		.size_in = sizeof(in),
1384 		.payload_in = &in,
1385 	};
1386 
1387 	return cxl_internal_send_cmd(cxl_mbox, &mbox_cmd);
1388 }
1389 EXPORT_SYMBOL_NS_GPL(cxl_arm_dirty_shutdown, "CXL");
1390 
cxl_set_timestamp(struct cxl_memdev_state * mds)1391 int cxl_set_timestamp(struct cxl_memdev_state *mds)
1392 {
1393 	struct cxl_mailbox *cxl_mbox = &mds->cxlds.cxl_mbox;
1394 	struct cxl_mbox_cmd mbox_cmd;
1395 	struct cxl_mbox_set_timestamp_in pi;
1396 	int rc;
1397 
1398 	pi.timestamp = cpu_to_le64(ktime_get_real_ns());
1399 	mbox_cmd = (struct cxl_mbox_cmd) {
1400 		.opcode = CXL_MBOX_OP_SET_TIMESTAMP,
1401 		.size_in = sizeof(pi),
1402 		.payload_in = &pi,
1403 	};
1404 
1405 	rc = cxl_internal_send_cmd(cxl_mbox, &mbox_cmd);
1406 	/*
1407 	 * Command is optional. Devices may have another way of providing
1408 	 * a timestamp, or may return all 0s in timestamp fields.
1409 	 * Don't report an error if this command isn't supported
1410 	 */
1411 	if (rc && (mbox_cmd.return_code != CXL_MBOX_CMD_RC_UNSUPPORTED))
1412 		return rc;
1413 
1414 	return 0;
1415 }
1416 EXPORT_SYMBOL_NS_GPL(cxl_set_timestamp, "CXL");
1417 
cxl_mem_get_poison(struct cxl_memdev * cxlmd,u64 offset,u64 len,struct cxl_region * cxlr)1418 int cxl_mem_get_poison(struct cxl_memdev *cxlmd, u64 offset, u64 len,
1419 		       struct cxl_region *cxlr)
1420 {
1421 	struct cxl_memdev_state *mds = to_cxl_memdev_state(cxlmd->cxlds);
1422 	struct cxl_mailbox *cxl_mbox = &cxlmd->cxlds->cxl_mbox;
1423 	struct cxl_mbox_poison_out *po;
1424 	struct cxl_mbox_poison_in pi;
1425 	int nr_records = 0;
1426 	int rc;
1427 
1428 	ACQUIRE(mutex_intr, lock)(&mds->poison.mutex);
1429 	if ((rc = ACQUIRE_ERR(mutex_intr, &lock)))
1430 		return rc;
1431 
1432 	po = mds->poison.list_out;
1433 	pi.offset = cpu_to_le64(offset);
1434 	pi.length = cpu_to_le64(len / CXL_POISON_LEN_MULT);
1435 
1436 	do {
1437 		struct cxl_mbox_cmd mbox_cmd = (struct cxl_mbox_cmd){
1438 			.opcode = CXL_MBOX_OP_GET_POISON,
1439 			.size_in = sizeof(pi),
1440 			.payload_in = &pi,
1441 			.size_out = cxl_mbox->payload_size,
1442 			.payload_out = po,
1443 			.min_out = struct_size(po, record, 0),
1444 		};
1445 
1446 		rc = cxl_internal_send_cmd(cxl_mbox, &mbox_cmd);
1447 		if (rc)
1448 			break;
1449 
1450 		for (int i = 0; i < le16_to_cpu(po->count); i++)
1451 			trace_cxl_poison(cxlmd, cxlr, &po->record[i],
1452 					 po->flags, po->overflow_ts,
1453 					 CXL_POISON_TRACE_LIST);
1454 
1455 		/* Protect against an uncleared _FLAG_MORE */
1456 		nr_records = nr_records + le16_to_cpu(po->count);
1457 		if (nr_records >= mds->poison.max_errors) {
1458 			dev_dbg(&cxlmd->dev, "Max Error Records reached: %d\n",
1459 				nr_records);
1460 			break;
1461 		}
1462 	} while (po->flags & CXL_POISON_FLAG_MORE);
1463 
1464 	return rc;
1465 }
1466 EXPORT_SYMBOL_NS_GPL(cxl_mem_get_poison, "CXL");
1467 
free_poison_buf(void * buf)1468 static void free_poison_buf(void *buf)
1469 {
1470 	kvfree(buf);
1471 }
1472 
1473 /* Get Poison List output buffer is protected by mds->poison.lock */
cxl_poison_alloc_buf(struct cxl_memdev_state * mds)1474 static int cxl_poison_alloc_buf(struct cxl_memdev_state *mds)
1475 {
1476 	struct cxl_mailbox *cxl_mbox = &mds->cxlds.cxl_mbox;
1477 
1478 	mds->poison.list_out = kvmalloc(cxl_mbox->payload_size, GFP_KERNEL);
1479 	if (!mds->poison.list_out)
1480 		return -ENOMEM;
1481 
1482 	return devm_add_action_or_reset(mds->cxlds.dev, free_poison_buf,
1483 					mds->poison.list_out);
1484 }
1485 
cxl_poison_state_init(struct cxl_memdev_state * mds)1486 int cxl_poison_state_init(struct cxl_memdev_state *mds)
1487 {
1488 	int rc;
1489 
1490 	if (!test_bit(CXL_POISON_ENABLED_LIST, mds->poison.enabled_cmds))
1491 		return 0;
1492 
1493 	rc = cxl_poison_alloc_buf(mds);
1494 	if (rc) {
1495 		clear_bit(CXL_POISON_ENABLED_LIST, mds->poison.enabled_cmds);
1496 		return rc;
1497 	}
1498 
1499 	mutex_init(&mds->poison.mutex);
1500 	return 0;
1501 }
1502 EXPORT_SYMBOL_NS_GPL(cxl_poison_state_init, "CXL");
1503 
cxl_mailbox_init(struct cxl_mailbox * cxl_mbox,struct device * host)1504 int cxl_mailbox_init(struct cxl_mailbox *cxl_mbox, struct device *host)
1505 {
1506 	if (!cxl_mbox || !host)
1507 		return -EINVAL;
1508 
1509 	cxl_mbox->host = host;
1510 	mutex_init(&cxl_mbox->mbox_mutex);
1511 	rcuwait_init(&cxl_mbox->mbox_wait);
1512 
1513 	return 0;
1514 }
1515 EXPORT_SYMBOL_NS_GPL(cxl_mailbox_init, "CXL");
1516 
cxl_memdev_state_create(struct device * dev)1517 struct cxl_memdev_state *cxl_memdev_state_create(struct device *dev)
1518 {
1519 	struct cxl_memdev_state *mds;
1520 	int rc;
1521 
1522 	mds = devm_kzalloc(dev, sizeof(*mds), GFP_KERNEL);
1523 	if (!mds) {
1524 		dev_err(dev, "No memory available\n");
1525 		return ERR_PTR(-ENOMEM);
1526 	}
1527 
1528 	mutex_init(&mds->event.log_lock);
1529 	mds->cxlds.dev = dev;
1530 	mds->cxlds.reg_map.host = dev;
1531 	mds->cxlds.cxl_mbox.host = dev;
1532 	mds->cxlds.reg_map.resource = CXL_RESOURCE_NONE;
1533 	mds->cxlds.type = CXL_DEVTYPE_CLASSMEM;
1534 
1535 	rc = devm_cxl_register_mce_notifier(dev, &mds->mce_notifier);
1536 	if (rc == -EOPNOTSUPP)
1537 		dev_warn(dev, "CXL MCE unsupported\n");
1538 	else if (rc)
1539 		return ERR_PTR(rc);
1540 
1541 	return mds;
1542 }
1543 EXPORT_SYMBOL_NS_GPL(cxl_memdev_state_create, "CXL");
1544 
cxl_mbox_init(void)1545 void __init cxl_mbox_init(void)
1546 {
1547 	struct dentry *mbox_debugfs;
1548 
1549 	mbox_debugfs = cxl_debugfs_create_dir("mbox");
1550 	debugfs_create_bool("raw_allow_all", 0600, mbox_debugfs,
1551 			    &cxl_raw_allow_all);
1552 }
1553