xref: /openbmc/linux/drivers/crypto/ccp/sev-dev.c (revision b38269ec)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * AMD Secure Encrypted Virtualization (SEV) interface
4  *
5  * Copyright (C) 2016,2019 Advanced Micro Devices, Inc.
6  *
7  * Author: Brijesh Singh <brijesh.singh@amd.com>
8  */
9 
10 #include <linux/module.h>
11 #include <linux/kernel.h>
12 #include <linux/kthread.h>
13 #include <linux/sched.h>
14 #include <linux/interrupt.h>
15 #include <linux/spinlock.h>
16 #include <linux/spinlock_types.h>
17 #include <linux/types.h>
18 #include <linux/mutex.h>
19 #include <linux/delay.h>
20 #include <linux/hw_random.h>
21 #include <linux/ccp.h>
22 #include <linux/firmware.h>
23 #include <linux/gfp.h>
24 #include <linux/cpufeature.h>
25 
26 #include <asm/smp.h>
27 
28 #include "psp-dev.h"
29 #include "sev-dev.h"
30 
31 #define DEVICE_NAME		"sev"
32 #define SEV_FW_FILE		"amd/sev.fw"
33 #define SEV_FW_NAME_SIZE	64
34 
35 static DEFINE_MUTEX(sev_cmd_mutex);
36 static struct sev_misc_dev *misc_dev;
37 
38 static int psp_cmd_timeout = 100;
39 module_param(psp_cmd_timeout, int, 0644);
40 MODULE_PARM_DESC(psp_cmd_timeout, " default timeout value, in seconds, for PSP commands");
41 
42 static int psp_probe_timeout = 5;
43 module_param(psp_probe_timeout, int, 0644);
44 MODULE_PARM_DESC(psp_probe_timeout, " default timeout value, in seconds, during PSP device probe");
45 
46 MODULE_FIRMWARE("amd/amd_sev_fam17h_model0xh.sbin"); /* 1st gen EPYC */
47 MODULE_FIRMWARE("amd/amd_sev_fam17h_model3xh.sbin"); /* 2nd gen EPYC */
48 MODULE_FIRMWARE("amd/amd_sev_fam19h_model0xh.sbin"); /* 3rd gen EPYC */
49 
50 static bool psp_dead;
51 static int psp_timeout;
52 
53 /* Trusted Memory Region (TMR):
54  *   The TMR is a 1MB area that must be 1MB aligned.  Use the page allocator
55  *   to allocate the memory, which will return aligned memory for the specified
56  *   allocation order.
57  */
58 #define SEV_ES_TMR_SIZE		(1024 * 1024)
59 static void *sev_es_tmr;
60 
61 static inline bool sev_version_greater_or_equal(u8 maj, u8 min)
62 {
63 	struct sev_device *sev = psp_master->sev_data;
64 
65 	if (sev->api_major > maj)
66 		return true;
67 
68 	if (sev->api_major == maj && sev->api_minor >= min)
69 		return true;
70 
71 	return false;
72 }
73 
74 static void sev_irq_handler(int irq, void *data, unsigned int status)
75 {
76 	struct sev_device *sev = data;
77 	int reg;
78 
79 	/* Check if it is command completion: */
80 	if (!(status & SEV_CMD_COMPLETE))
81 		return;
82 
83 	/* Check if it is SEV command completion: */
84 	reg = ioread32(sev->io_regs + sev->vdata->cmdresp_reg);
85 	if (reg & PSP_CMDRESP_RESP) {
86 		sev->int_rcvd = 1;
87 		wake_up(&sev->int_queue);
88 	}
89 }
90 
91 static int sev_wait_cmd_ioc(struct sev_device *sev,
92 			    unsigned int *reg, unsigned int timeout)
93 {
94 	int ret;
95 
96 	ret = wait_event_timeout(sev->int_queue,
97 			sev->int_rcvd, timeout * HZ);
98 	if (!ret)
99 		return -ETIMEDOUT;
100 
101 	*reg = ioread32(sev->io_regs + sev->vdata->cmdresp_reg);
102 
103 	return 0;
104 }
105 
106 static int sev_cmd_buffer_len(int cmd)
107 {
108 	switch (cmd) {
109 	case SEV_CMD_INIT:			return sizeof(struct sev_data_init);
110 	case SEV_CMD_PLATFORM_STATUS:		return sizeof(struct sev_user_data_status);
111 	case SEV_CMD_PEK_CSR:			return sizeof(struct sev_data_pek_csr);
112 	case SEV_CMD_PEK_CERT_IMPORT:		return sizeof(struct sev_data_pek_cert_import);
113 	case SEV_CMD_PDH_CERT_EXPORT:		return sizeof(struct sev_data_pdh_cert_export);
114 	case SEV_CMD_LAUNCH_START:		return sizeof(struct sev_data_launch_start);
115 	case SEV_CMD_LAUNCH_UPDATE_DATA:	return sizeof(struct sev_data_launch_update_data);
116 	case SEV_CMD_LAUNCH_UPDATE_VMSA:	return sizeof(struct sev_data_launch_update_vmsa);
117 	case SEV_CMD_LAUNCH_FINISH:		return sizeof(struct sev_data_launch_finish);
118 	case SEV_CMD_LAUNCH_MEASURE:		return sizeof(struct sev_data_launch_measure);
119 	case SEV_CMD_ACTIVATE:			return sizeof(struct sev_data_activate);
120 	case SEV_CMD_DEACTIVATE:		return sizeof(struct sev_data_deactivate);
121 	case SEV_CMD_DECOMMISSION:		return sizeof(struct sev_data_decommission);
122 	case SEV_CMD_GUEST_STATUS:		return sizeof(struct sev_data_guest_status);
123 	case SEV_CMD_DBG_DECRYPT:		return sizeof(struct sev_data_dbg);
124 	case SEV_CMD_DBG_ENCRYPT:		return sizeof(struct sev_data_dbg);
125 	case SEV_CMD_SEND_START:		return sizeof(struct sev_data_send_start);
126 	case SEV_CMD_SEND_UPDATE_DATA:		return sizeof(struct sev_data_send_update_data);
127 	case SEV_CMD_SEND_UPDATE_VMSA:		return sizeof(struct sev_data_send_update_vmsa);
128 	case SEV_CMD_SEND_FINISH:		return sizeof(struct sev_data_send_finish);
129 	case SEV_CMD_RECEIVE_START:		return sizeof(struct sev_data_receive_start);
130 	case SEV_CMD_RECEIVE_FINISH:		return sizeof(struct sev_data_receive_finish);
131 	case SEV_CMD_RECEIVE_UPDATE_DATA:	return sizeof(struct sev_data_receive_update_data);
132 	case SEV_CMD_RECEIVE_UPDATE_VMSA:	return sizeof(struct sev_data_receive_update_vmsa);
133 	case SEV_CMD_LAUNCH_UPDATE_SECRET:	return sizeof(struct sev_data_launch_secret);
134 	case SEV_CMD_DOWNLOAD_FIRMWARE:		return sizeof(struct sev_data_download_firmware);
135 	case SEV_CMD_GET_ID:			return sizeof(struct sev_data_get_id);
136 	case SEV_CMD_ATTESTATION_REPORT:	return sizeof(struct sev_data_attestation_report);
137 	case SEV_CMD_SEND_CANCEL:			return sizeof(struct sev_data_send_cancel);
138 	default:				return 0;
139 	}
140 
141 	return 0;
142 }
143 
144 static int __sev_do_cmd_locked(int cmd, void *data, int *psp_ret)
145 {
146 	struct psp_device *psp = psp_master;
147 	struct sev_device *sev;
148 	unsigned int phys_lsb, phys_msb;
149 	unsigned int reg, ret = 0;
150 	int buf_len;
151 
152 	if (!psp || !psp->sev_data)
153 		return -ENODEV;
154 
155 	if (psp_dead)
156 		return -EBUSY;
157 
158 	sev = psp->sev_data;
159 
160 	buf_len = sev_cmd_buffer_len(cmd);
161 	if (WARN_ON_ONCE(!data != !buf_len))
162 		return -EINVAL;
163 
164 	/*
165 	 * Copy the incoming data to driver's scratch buffer as __pa() will not
166 	 * work for some memory, e.g. vmalloc'd addresses, and @data may not be
167 	 * physically contiguous.
168 	 */
169 	if (data)
170 		memcpy(sev->cmd_buf, data, buf_len);
171 
172 	/* Get the physical address of the command buffer */
173 	phys_lsb = data ? lower_32_bits(__psp_pa(sev->cmd_buf)) : 0;
174 	phys_msb = data ? upper_32_bits(__psp_pa(sev->cmd_buf)) : 0;
175 
176 	dev_dbg(sev->dev, "sev command id %#x buffer 0x%08x%08x timeout %us\n",
177 		cmd, phys_msb, phys_lsb, psp_timeout);
178 
179 	print_hex_dump_debug("(in):  ", DUMP_PREFIX_OFFSET, 16, 2, data,
180 			     buf_len, false);
181 
182 	iowrite32(phys_lsb, sev->io_regs + sev->vdata->cmdbuff_addr_lo_reg);
183 	iowrite32(phys_msb, sev->io_regs + sev->vdata->cmdbuff_addr_hi_reg);
184 
185 	sev->int_rcvd = 0;
186 
187 	reg = cmd;
188 	reg <<= SEV_CMDRESP_CMD_SHIFT;
189 	reg |= SEV_CMDRESP_IOC;
190 	iowrite32(reg, sev->io_regs + sev->vdata->cmdresp_reg);
191 
192 	/* wait for command completion */
193 	ret = sev_wait_cmd_ioc(sev, &reg, psp_timeout);
194 	if (ret) {
195 		if (psp_ret)
196 			*psp_ret = 0;
197 
198 		dev_err(sev->dev, "sev command %#x timed out, disabling PSP\n", cmd);
199 		psp_dead = true;
200 
201 		return ret;
202 	}
203 
204 	psp_timeout = psp_cmd_timeout;
205 
206 	if (psp_ret)
207 		*psp_ret = reg & PSP_CMDRESP_ERR_MASK;
208 
209 	if (reg & PSP_CMDRESP_ERR_MASK) {
210 		dev_dbg(sev->dev, "sev command %#x failed (%#010x)\n",
211 			cmd, reg & PSP_CMDRESP_ERR_MASK);
212 		ret = -EIO;
213 	}
214 
215 	print_hex_dump_debug("(out): ", DUMP_PREFIX_OFFSET, 16, 2, data,
216 			     buf_len, false);
217 
218 	/*
219 	 * Copy potential output from the PSP back to data.  Do this even on
220 	 * failure in case the caller wants to glean something from the error.
221 	 */
222 	if (data)
223 		memcpy(data, sev->cmd_buf, buf_len);
224 
225 	return ret;
226 }
227 
228 static int sev_do_cmd(int cmd, void *data, int *psp_ret)
229 {
230 	int rc;
231 
232 	mutex_lock(&sev_cmd_mutex);
233 	rc = __sev_do_cmd_locked(cmd, data, psp_ret);
234 	mutex_unlock(&sev_cmd_mutex);
235 
236 	return rc;
237 }
238 
239 static int __sev_platform_init_locked(int *error)
240 {
241 	struct psp_device *psp = psp_master;
242 	struct sev_data_init data;
243 	struct sev_device *sev;
244 	int rc = 0;
245 
246 	if (!psp || !psp->sev_data)
247 		return -ENODEV;
248 
249 	sev = psp->sev_data;
250 
251 	if (sev->state == SEV_STATE_INIT)
252 		return 0;
253 
254 	memset(&data, 0, sizeof(data));
255 	if (sev_es_tmr) {
256 		u64 tmr_pa;
257 
258 		/*
259 		 * Do not include the encryption mask on the physical
260 		 * address of the TMR (firmware should clear it anyway).
261 		 */
262 		tmr_pa = __pa(sev_es_tmr);
263 
264 		data.flags |= SEV_INIT_FLAGS_SEV_ES;
265 		data.tmr_address = tmr_pa;
266 		data.tmr_len = SEV_ES_TMR_SIZE;
267 	}
268 
269 	rc = __sev_do_cmd_locked(SEV_CMD_INIT, &data, error);
270 	if (rc)
271 		return rc;
272 
273 	sev->state = SEV_STATE_INIT;
274 
275 	/* Prepare for first SEV guest launch after INIT */
276 	wbinvd_on_all_cpus();
277 	rc = __sev_do_cmd_locked(SEV_CMD_DF_FLUSH, NULL, error);
278 	if (rc)
279 		return rc;
280 
281 	dev_dbg(sev->dev, "SEV firmware initialized\n");
282 
283 	return rc;
284 }
285 
286 int sev_platform_init(int *error)
287 {
288 	int rc;
289 
290 	mutex_lock(&sev_cmd_mutex);
291 	rc = __sev_platform_init_locked(error);
292 	mutex_unlock(&sev_cmd_mutex);
293 
294 	return rc;
295 }
296 EXPORT_SYMBOL_GPL(sev_platform_init);
297 
298 static int __sev_platform_shutdown_locked(int *error)
299 {
300 	struct sev_device *sev = psp_master->sev_data;
301 	int ret;
302 
303 	if (sev->state == SEV_STATE_UNINIT)
304 		return 0;
305 
306 	ret = __sev_do_cmd_locked(SEV_CMD_SHUTDOWN, NULL, error);
307 	if (ret)
308 		return ret;
309 
310 	sev->state = SEV_STATE_UNINIT;
311 	dev_dbg(sev->dev, "SEV firmware shutdown\n");
312 
313 	return ret;
314 }
315 
316 static int sev_platform_shutdown(int *error)
317 {
318 	int rc;
319 
320 	mutex_lock(&sev_cmd_mutex);
321 	rc = __sev_platform_shutdown_locked(NULL);
322 	mutex_unlock(&sev_cmd_mutex);
323 
324 	return rc;
325 }
326 
327 static int sev_get_platform_state(int *state, int *error)
328 {
329 	struct sev_user_data_status data;
330 	int rc;
331 
332 	rc = __sev_do_cmd_locked(SEV_CMD_PLATFORM_STATUS, &data, error);
333 	if (rc)
334 		return rc;
335 
336 	*state = data.state;
337 	return rc;
338 }
339 
340 static int sev_ioctl_do_reset(struct sev_issue_cmd *argp, bool writable)
341 {
342 	int state, rc;
343 
344 	if (!writable)
345 		return -EPERM;
346 
347 	/*
348 	 * The SEV spec requires that FACTORY_RESET must be issued in
349 	 * UNINIT state. Before we go further lets check if any guest is
350 	 * active.
351 	 *
352 	 * If FW is in WORKING state then deny the request otherwise issue
353 	 * SHUTDOWN command do INIT -> UNINIT before issuing the FACTORY_RESET.
354 	 *
355 	 */
356 	rc = sev_get_platform_state(&state, &argp->error);
357 	if (rc)
358 		return rc;
359 
360 	if (state == SEV_STATE_WORKING)
361 		return -EBUSY;
362 
363 	if (state == SEV_STATE_INIT) {
364 		rc = __sev_platform_shutdown_locked(&argp->error);
365 		if (rc)
366 			return rc;
367 	}
368 
369 	return __sev_do_cmd_locked(SEV_CMD_FACTORY_RESET, NULL, &argp->error);
370 }
371 
372 static int sev_ioctl_do_platform_status(struct sev_issue_cmd *argp)
373 {
374 	struct sev_user_data_status data;
375 	int ret;
376 
377 	ret = __sev_do_cmd_locked(SEV_CMD_PLATFORM_STATUS, &data, &argp->error);
378 	if (ret)
379 		return ret;
380 
381 	if (copy_to_user((void __user *)argp->data, &data, sizeof(data)))
382 		ret = -EFAULT;
383 
384 	return ret;
385 }
386 
387 static int sev_ioctl_do_pek_pdh_gen(int cmd, struct sev_issue_cmd *argp, bool writable)
388 {
389 	struct sev_device *sev = psp_master->sev_data;
390 	int rc;
391 
392 	if (!writable)
393 		return -EPERM;
394 
395 	if (sev->state == SEV_STATE_UNINIT) {
396 		rc = __sev_platform_init_locked(&argp->error);
397 		if (rc)
398 			return rc;
399 	}
400 
401 	return __sev_do_cmd_locked(cmd, NULL, &argp->error);
402 }
403 
404 static int sev_ioctl_do_pek_csr(struct sev_issue_cmd *argp, bool writable)
405 {
406 	struct sev_device *sev = psp_master->sev_data;
407 	struct sev_user_data_pek_csr input;
408 	struct sev_data_pek_csr data;
409 	void __user *input_address;
410 	void *blob = NULL;
411 	int ret;
412 
413 	if (!writable)
414 		return -EPERM;
415 
416 	if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
417 		return -EFAULT;
418 
419 	memset(&data, 0, sizeof(data));
420 
421 	/* userspace wants to query CSR length */
422 	if (!input.address || !input.length)
423 		goto cmd;
424 
425 	/* allocate a physically contiguous buffer to store the CSR blob */
426 	input_address = (void __user *)input.address;
427 	if (input.length > SEV_FW_BLOB_MAX_SIZE)
428 		return -EFAULT;
429 
430 	blob = kmalloc(input.length, GFP_KERNEL);
431 	if (!blob)
432 		return -ENOMEM;
433 
434 	data.address = __psp_pa(blob);
435 	data.len = input.length;
436 
437 cmd:
438 	if (sev->state == SEV_STATE_UNINIT) {
439 		ret = __sev_platform_init_locked(&argp->error);
440 		if (ret)
441 			goto e_free_blob;
442 	}
443 
444 	ret = __sev_do_cmd_locked(SEV_CMD_PEK_CSR, &data, &argp->error);
445 
446 	 /* If we query the CSR length, FW responded with expected data. */
447 	input.length = data.len;
448 
449 	if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) {
450 		ret = -EFAULT;
451 		goto e_free_blob;
452 	}
453 
454 	if (blob) {
455 		if (copy_to_user(input_address, blob, input.length))
456 			ret = -EFAULT;
457 	}
458 
459 e_free_blob:
460 	kfree(blob);
461 	return ret;
462 }
463 
464 void *psp_copy_user_blob(u64 uaddr, u32 len)
465 {
466 	if (!uaddr || !len)
467 		return ERR_PTR(-EINVAL);
468 
469 	/* verify that blob length does not exceed our limit */
470 	if (len > SEV_FW_BLOB_MAX_SIZE)
471 		return ERR_PTR(-EINVAL);
472 
473 	return memdup_user((void __user *)uaddr, len);
474 }
475 EXPORT_SYMBOL_GPL(psp_copy_user_blob);
476 
477 static int sev_get_api_version(void)
478 {
479 	struct sev_device *sev = psp_master->sev_data;
480 	struct sev_user_data_status status;
481 	int error = 0, ret;
482 
483 	ret = sev_platform_status(&status, &error);
484 	if (ret) {
485 		dev_err(sev->dev,
486 			"SEV: failed to get status. Error: %#x\n", error);
487 		return 1;
488 	}
489 
490 	sev->api_major = status.api_major;
491 	sev->api_minor = status.api_minor;
492 	sev->build = status.build;
493 	sev->state = status.state;
494 
495 	return 0;
496 }
497 
498 static int sev_get_firmware(struct device *dev,
499 			    const struct firmware **firmware)
500 {
501 	char fw_name_specific[SEV_FW_NAME_SIZE];
502 	char fw_name_subset[SEV_FW_NAME_SIZE];
503 
504 	snprintf(fw_name_specific, sizeof(fw_name_specific),
505 		 "amd/amd_sev_fam%.2xh_model%.2xh.sbin",
506 		 boot_cpu_data.x86, boot_cpu_data.x86_model);
507 
508 	snprintf(fw_name_subset, sizeof(fw_name_subset),
509 		 "amd/amd_sev_fam%.2xh_model%.1xxh.sbin",
510 		 boot_cpu_data.x86, (boot_cpu_data.x86_model & 0xf0) >> 4);
511 
512 	/* Check for SEV FW for a particular model.
513 	 * Ex. amd_sev_fam17h_model00h.sbin for Family 17h Model 00h
514 	 *
515 	 * or
516 	 *
517 	 * Check for SEV FW common to a subset of models.
518 	 * Ex. amd_sev_fam17h_model0xh.sbin for
519 	 *     Family 17h Model 00h -- Family 17h Model 0Fh
520 	 *
521 	 * or
522 	 *
523 	 * Fall-back to using generic name: sev.fw
524 	 */
525 	if ((firmware_request_nowarn(firmware, fw_name_specific, dev) >= 0) ||
526 	    (firmware_request_nowarn(firmware, fw_name_subset, dev) >= 0) ||
527 	    (firmware_request_nowarn(firmware, SEV_FW_FILE, dev) >= 0))
528 		return 0;
529 
530 	return -ENOENT;
531 }
532 
533 /* Don't fail if SEV FW couldn't be updated. Continue with existing SEV FW */
534 static int sev_update_firmware(struct device *dev)
535 {
536 	struct sev_data_download_firmware *data;
537 	const struct firmware *firmware;
538 	int ret, error, order;
539 	struct page *p;
540 	u64 data_size;
541 
542 	if (sev_get_firmware(dev, &firmware) == -ENOENT) {
543 		dev_dbg(dev, "No SEV firmware file present\n");
544 		return -1;
545 	}
546 
547 	/*
548 	 * SEV FW expects the physical address given to it to be 32
549 	 * byte aligned. Memory allocated has structure placed at the
550 	 * beginning followed by the firmware being passed to the SEV
551 	 * FW. Allocate enough memory for data structure + alignment
552 	 * padding + SEV FW.
553 	 */
554 	data_size = ALIGN(sizeof(struct sev_data_download_firmware), 32);
555 
556 	order = get_order(firmware->size + data_size);
557 	p = alloc_pages(GFP_KERNEL, order);
558 	if (!p) {
559 		ret = -1;
560 		goto fw_err;
561 	}
562 
563 	/*
564 	 * Copy firmware data to a kernel allocated contiguous
565 	 * memory region.
566 	 */
567 	data = page_address(p);
568 	memcpy(page_address(p) + data_size, firmware->data, firmware->size);
569 
570 	data->address = __psp_pa(page_address(p) + data_size);
571 	data->len = firmware->size;
572 
573 	ret = sev_do_cmd(SEV_CMD_DOWNLOAD_FIRMWARE, data, &error);
574 	if (ret)
575 		dev_dbg(dev, "Failed to update SEV firmware: %#x\n", error);
576 	else
577 		dev_info(dev, "SEV firmware update successful\n");
578 
579 	__free_pages(p, order);
580 
581 fw_err:
582 	release_firmware(firmware);
583 
584 	return ret;
585 }
586 
587 static int sev_ioctl_do_pek_import(struct sev_issue_cmd *argp, bool writable)
588 {
589 	struct sev_device *sev = psp_master->sev_data;
590 	struct sev_user_data_pek_cert_import input;
591 	struct sev_data_pek_cert_import data;
592 	void *pek_blob, *oca_blob;
593 	int ret;
594 
595 	if (!writable)
596 		return -EPERM;
597 
598 	if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
599 		return -EFAULT;
600 
601 	/* copy PEK certificate blobs from userspace */
602 	pek_blob = psp_copy_user_blob(input.pek_cert_address, input.pek_cert_len);
603 	if (IS_ERR(pek_blob))
604 		return PTR_ERR(pek_blob);
605 
606 	data.reserved = 0;
607 	data.pek_cert_address = __psp_pa(pek_blob);
608 	data.pek_cert_len = input.pek_cert_len;
609 
610 	/* copy PEK certificate blobs from userspace */
611 	oca_blob = psp_copy_user_blob(input.oca_cert_address, input.oca_cert_len);
612 	if (IS_ERR(oca_blob)) {
613 		ret = PTR_ERR(oca_blob);
614 		goto e_free_pek;
615 	}
616 
617 	data.oca_cert_address = __psp_pa(oca_blob);
618 	data.oca_cert_len = input.oca_cert_len;
619 
620 	/* If platform is not in INIT state then transition it to INIT */
621 	if (sev->state != SEV_STATE_INIT) {
622 		ret = __sev_platform_init_locked(&argp->error);
623 		if (ret)
624 			goto e_free_oca;
625 	}
626 
627 	ret = __sev_do_cmd_locked(SEV_CMD_PEK_CERT_IMPORT, &data, &argp->error);
628 
629 e_free_oca:
630 	kfree(oca_blob);
631 e_free_pek:
632 	kfree(pek_blob);
633 	return ret;
634 }
635 
636 static int sev_ioctl_do_get_id2(struct sev_issue_cmd *argp)
637 {
638 	struct sev_user_data_get_id2 input;
639 	struct sev_data_get_id data;
640 	void __user *input_address;
641 	void *id_blob = NULL;
642 	int ret;
643 
644 	/* SEV GET_ID is available from SEV API v0.16 and up */
645 	if (!sev_version_greater_or_equal(0, 16))
646 		return -ENOTSUPP;
647 
648 	if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
649 		return -EFAULT;
650 
651 	input_address = (void __user *)input.address;
652 
653 	if (input.address && input.length) {
654 		id_blob = kmalloc(input.length, GFP_KERNEL);
655 		if (!id_blob)
656 			return -ENOMEM;
657 
658 		data.address = __psp_pa(id_blob);
659 		data.len = input.length;
660 	} else {
661 		data.address = 0;
662 		data.len = 0;
663 	}
664 
665 	ret = __sev_do_cmd_locked(SEV_CMD_GET_ID, &data, &argp->error);
666 
667 	/*
668 	 * Firmware will return the length of the ID value (either the minimum
669 	 * required length or the actual length written), return it to the user.
670 	 */
671 	input.length = data.len;
672 
673 	if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) {
674 		ret = -EFAULT;
675 		goto e_free;
676 	}
677 
678 	if (id_blob) {
679 		if (copy_to_user(input_address, id_blob, data.len)) {
680 			ret = -EFAULT;
681 			goto e_free;
682 		}
683 	}
684 
685 e_free:
686 	kfree(id_blob);
687 
688 	return ret;
689 }
690 
691 static int sev_ioctl_do_get_id(struct sev_issue_cmd *argp)
692 {
693 	struct sev_data_get_id *data;
694 	u64 data_size, user_size;
695 	void *id_blob, *mem;
696 	int ret;
697 
698 	/* SEV GET_ID available from SEV API v0.16 and up */
699 	if (!sev_version_greater_or_equal(0, 16))
700 		return -ENOTSUPP;
701 
702 	/* SEV FW expects the buffer it fills with the ID to be
703 	 * 8-byte aligned. Memory allocated should be enough to
704 	 * hold data structure + alignment padding + memory
705 	 * where SEV FW writes the ID.
706 	 */
707 	data_size = ALIGN(sizeof(struct sev_data_get_id), 8);
708 	user_size = sizeof(struct sev_user_data_get_id);
709 
710 	mem = kzalloc(data_size + user_size, GFP_KERNEL);
711 	if (!mem)
712 		return -ENOMEM;
713 
714 	data = mem;
715 	id_blob = mem + data_size;
716 
717 	data->address = __psp_pa(id_blob);
718 	data->len = user_size;
719 
720 	ret = __sev_do_cmd_locked(SEV_CMD_GET_ID, data, &argp->error);
721 	if (!ret) {
722 		if (copy_to_user((void __user *)argp->data, id_blob, data->len))
723 			ret = -EFAULT;
724 	}
725 
726 	kfree(mem);
727 
728 	return ret;
729 }
730 
731 static int sev_ioctl_do_pdh_export(struct sev_issue_cmd *argp, bool writable)
732 {
733 	struct sev_device *sev = psp_master->sev_data;
734 	struct sev_user_data_pdh_cert_export input;
735 	void *pdh_blob = NULL, *cert_blob = NULL;
736 	struct sev_data_pdh_cert_export data;
737 	void __user *input_cert_chain_address;
738 	void __user *input_pdh_cert_address;
739 	int ret;
740 
741 	/* If platform is not in INIT state then transition it to INIT. */
742 	if (sev->state != SEV_STATE_INIT) {
743 		if (!writable)
744 			return -EPERM;
745 
746 		ret = __sev_platform_init_locked(&argp->error);
747 		if (ret)
748 			return ret;
749 	}
750 
751 	if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
752 		return -EFAULT;
753 
754 	memset(&data, 0, sizeof(data));
755 
756 	/* Userspace wants to query the certificate length. */
757 	if (!input.pdh_cert_address ||
758 	    !input.pdh_cert_len ||
759 	    !input.cert_chain_address)
760 		goto cmd;
761 
762 	input_pdh_cert_address = (void __user *)input.pdh_cert_address;
763 	input_cert_chain_address = (void __user *)input.cert_chain_address;
764 
765 	/* Allocate a physically contiguous buffer to store the PDH blob. */
766 	if (input.pdh_cert_len > SEV_FW_BLOB_MAX_SIZE)
767 		return -EFAULT;
768 
769 	/* Allocate a physically contiguous buffer to store the cert chain blob. */
770 	if (input.cert_chain_len > SEV_FW_BLOB_MAX_SIZE)
771 		return -EFAULT;
772 
773 	pdh_blob = kmalloc(input.pdh_cert_len, GFP_KERNEL);
774 	if (!pdh_blob)
775 		return -ENOMEM;
776 
777 	data.pdh_cert_address = __psp_pa(pdh_blob);
778 	data.pdh_cert_len = input.pdh_cert_len;
779 
780 	cert_blob = kmalloc(input.cert_chain_len, GFP_KERNEL);
781 	if (!cert_blob) {
782 		ret = -ENOMEM;
783 		goto e_free_pdh;
784 	}
785 
786 	data.cert_chain_address = __psp_pa(cert_blob);
787 	data.cert_chain_len = input.cert_chain_len;
788 
789 cmd:
790 	ret = __sev_do_cmd_locked(SEV_CMD_PDH_CERT_EXPORT, &data, &argp->error);
791 
792 	/* If we query the length, FW responded with expected data. */
793 	input.cert_chain_len = data.cert_chain_len;
794 	input.pdh_cert_len = data.pdh_cert_len;
795 
796 	if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) {
797 		ret = -EFAULT;
798 		goto e_free_cert;
799 	}
800 
801 	if (pdh_blob) {
802 		if (copy_to_user(input_pdh_cert_address,
803 				 pdh_blob, input.pdh_cert_len)) {
804 			ret = -EFAULT;
805 			goto e_free_cert;
806 		}
807 	}
808 
809 	if (cert_blob) {
810 		if (copy_to_user(input_cert_chain_address,
811 				 cert_blob, input.cert_chain_len))
812 			ret = -EFAULT;
813 	}
814 
815 e_free_cert:
816 	kfree(cert_blob);
817 e_free_pdh:
818 	kfree(pdh_blob);
819 	return ret;
820 }
821 
822 static long sev_ioctl(struct file *file, unsigned int ioctl, unsigned long arg)
823 {
824 	void __user *argp = (void __user *)arg;
825 	struct sev_issue_cmd input;
826 	int ret = -EFAULT;
827 	bool writable = file->f_mode & FMODE_WRITE;
828 
829 	if (!psp_master || !psp_master->sev_data)
830 		return -ENODEV;
831 
832 	if (ioctl != SEV_ISSUE_CMD)
833 		return -EINVAL;
834 
835 	if (copy_from_user(&input, argp, sizeof(struct sev_issue_cmd)))
836 		return -EFAULT;
837 
838 	if (input.cmd > SEV_MAX)
839 		return -EINVAL;
840 
841 	mutex_lock(&sev_cmd_mutex);
842 
843 	switch (input.cmd) {
844 
845 	case SEV_FACTORY_RESET:
846 		ret = sev_ioctl_do_reset(&input, writable);
847 		break;
848 	case SEV_PLATFORM_STATUS:
849 		ret = sev_ioctl_do_platform_status(&input);
850 		break;
851 	case SEV_PEK_GEN:
852 		ret = sev_ioctl_do_pek_pdh_gen(SEV_CMD_PEK_GEN, &input, writable);
853 		break;
854 	case SEV_PDH_GEN:
855 		ret = sev_ioctl_do_pek_pdh_gen(SEV_CMD_PDH_GEN, &input, writable);
856 		break;
857 	case SEV_PEK_CSR:
858 		ret = sev_ioctl_do_pek_csr(&input, writable);
859 		break;
860 	case SEV_PEK_CERT_IMPORT:
861 		ret = sev_ioctl_do_pek_import(&input, writable);
862 		break;
863 	case SEV_PDH_CERT_EXPORT:
864 		ret = sev_ioctl_do_pdh_export(&input, writable);
865 		break;
866 	case SEV_GET_ID:
867 		pr_warn_once("SEV_GET_ID command is deprecated, use SEV_GET_ID2\n");
868 		ret = sev_ioctl_do_get_id(&input);
869 		break;
870 	case SEV_GET_ID2:
871 		ret = sev_ioctl_do_get_id2(&input);
872 		break;
873 	default:
874 		ret = -EINVAL;
875 		goto out;
876 	}
877 
878 	if (copy_to_user(argp, &input, sizeof(struct sev_issue_cmd)))
879 		ret = -EFAULT;
880 out:
881 	mutex_unlock(&sev_cmd_mutex);
882 
883 	return ret;
884 }
885 
886 static const struct file_operations sev_fops = {
887 	.owner	= THIS_MODULE,
888 	.unlocked_ioctl = sev_ioctl,
889 };
890 
891 int sev_platform_status(struct sev_user_data_status *data, int *error)
892 {
893 	return sev_do_cmd(SEV_CMD_PLATFORM_STATUS, data, error);
894 }
895 EXPORT_SYMBOL_GPL(sev_platform_status);
896 
897 int sev_guest_deactivate(struct sev_data_deactivate *data, int *error)
898 {
899 	return sev_do_cmd(SEV_CMD_DEACTIVATE, data, error);
900 }
901 EXPORT_SYMBOL_GPL(sev_guest_deactivate);
902 
903 int sev_guest_activate(struct sev_data_activate *data, int *error)
904 {
905 	return sev_do_cmd(SEV_CMD_ACTIVATE, data, error);
906 }
907 EXPORT_SYMBOL_GPL(sev_guest_activate);
908 
909 int sev_guest_decommission(struct sev_data_decommission *data, int *error)
910 {
911 	return sev_do_cmd(SEV_CMD_DECOMMISSION, data, error);
912 }
913 EXPORT_SYMBOL_GPL(sev_guest_decommission);
914 
915 int sev_guest_df_flush(int *error)
916 {
917 	return sev_do_cmd(SEV_CMD_DF_FLUSH, NULL, error);
918 }
919 EXPORT_SYMBOL_GPL(sev_guest_df_flush);
920 
921 static void sev_exit(struct kref *ref)
922 {
923 	misc_deregister(&misc_dev->misc);
924 	kfree(misc_dev);
925 	misc_dev = NULL;
926 }
927 
928 static int sev_misc_init(struct sev_device *sev)
929 {
930 	struct device *dev = sev->dev;
931 	int ret;
932 
933 	/*
934 	 * SEV feature support can be detected on multiple devices but the SEV
935 	 * FW commands must be issued on the master. During probe, we do not
936 	 * know the master hence we create /dev/sev on the first device probe.
937 	 * sev_do_cmd() finds the right master device to which to issue the
938 	 * command to the firmware.
939 	 */
940 	if (!misc_dev) {
941 		struct miscdevice *misc;
942 
943 		misc_dev = kzalloc(sizeof(*misc_dev), GFP_KERNEL);
944 		if (!misc_dev)
945 			return -ENOMEM;
946 
947 		misc = &misc_dev->misc;
948 		misc->minor = MISC_DYNAMIC_MINOR;
949 		misc->name = DEVICE_NAME;
950 		misc->fops = &sev_fops;
951 
952 		ret = misc_register(misc);
953 		if (ret)
954 			return ret;
955 
956 		kref_init(&misc_dev->refcount);
957 	} else {
958 		kref_get(&misc_dev->refcount);
959 	}
960 
961 	init_waitqueue_head(&sev->int_queue);
962 	sev->misc = misc_dev;
963 	dev_dbg(dev, "registered SEV device\n");
964 
965 	return 0;
966 }
967 
968 int sev_dev_init(struct psp_device *psp)
969 {
970 	struct device *dev = psp->dev;
971 	struct sev_device *sev;
972 	int ret = -ENOMEM;
973 
974 	if (!boot_cpu_has(X86_FEATURE_SEV)) {
975 		dev_info_once(dev, "SEV: memory encryption not enabled by BIOS\n");
976 		return 0;
977 	}
978 
979 	sev = devm_kzalloc(dev, sizeof(*sev), GFP_KERNEL);
980 	if (!sev)
981 		goto e_err;
982 
983 	sev->cmd_buf = (void *)devm_get_free_pages(dev, GFP_KERNEL, 0);
984 	if (!sev->cmd_buf)
985 		goto e_sev;
986 
987 	psp->sev_data = sev;
988 
989 	sev->dev = dev;
990 	sev->psp = psp;
991 
992 	sev->io_regs = psp->io_regs;
993 
994 	sev->vdata = (struct sev_vdata *)psp->vdata->sev;
995 	if (!sev->vdata) {
996 		ret = -ENODEV;
997 		dev_err(dev, "sev: missing driver data\n");
998 		goto e_buf;
999 	}
1000 
1001 	psp_set_sev_irq_handler(psp, sev_irq_handler, sev);
1002 
1003 	ret = sev_misc_init(sev);
1004 	if (ret)
1005 		goto e_irq;
1006 
1007 	dev_notice(dev, "sev enabled\n");
1008 
1009 	return 0;
1010 
1011 e_irq:
1012 	psp_clear_sev_irq_handler(psp);
1013 e_buf:
1014 	devm_free_pages(dev, (unsigned long)sev->cmd_buf);
1015 e_sev:
1016 	devm_kfree(dev, sev);
1017 e_err:
1018 	psp->sev_data = NULL;
1019 
1020 	dev_notice(dev, "sev initialization failed\n");
1021 
1022 	return ret;
1023 }
1024 
1025 static void sev_firmware_shutdown(struct sev_device *sev)
1026 {
1027 	sev_platform_shutdown(NULL);
1028 
1029 	if (sev_es_tmr) {
1030 		/* The TMR area was encrypted, flush it from the cache */
1031 		wbinvd_on_all_cpus();
1032 
1033 		free_pages((unsigned long)sev_es_tmr,
1034 			   get_order(SEV_ES_TMR_SIZE));
1035 		sev_es_tmr = NULL;
1036 	}
1037 }
1038 
1039 void sev_dev_destroy(struct psp_device *psp)
1040 {
1041 	struct sev_device *sev = psp->sev_data;
1042 
1043 	if (!sev)
1044 		return;
1045 
1046 	sev_firmware_shutdown(sev);
1047 
1048 	if (sev->misc)
1049 		kref_put(&misc_dev->refcount, sev_exit);
1050 
1051 	psp_clear_sev_irq_handler(psp);
1052 }
1053 
1054 int sev_issue_cmd_external_user(struct file *filep, unsigned int cmd,
1055 				void *data, int *error)
1056 {
1057 	if (!filep || filep->f_op != &sev_fops)
1058 		return -EBADF;
1059 
1060 	return sev_do_cmd(cmd, data, error);
1061 }
1062 EXPORT_SYMBOL_GPL(sev_issue_cmd_external_user);
1063 
1064 void sev_pci_init(void)
1065 {
1066 	struct sev_device *sev = psp_master->sev_data;
1067 	struct page *tmr_page;
1068 	int error, rc;
1069 
1070 	if (!sev)
1071 		return;
1072 
1073 	psp_timeout = psp_probe_timeout;
1074 
1075 	if (sev_get_api_version())
1076 		goto err;
1077 
1078 	if (sev_version_greater_or_equal(0, 15) &&
1079 	    sev_update_firmware(sev->dev) == 0)
1080 		sev_get_api_version();
1081 
1082 	/* Obtain the TMR memory area for SEV-ES use */
1083 	tmr_page = alloc_pages(GFP_KERNEL, get_order(SEV_ES_TMR_SIZE));
1084 	if (tmr_page) {
1085 		sev_es_tmr = page_address(tmr_page);
1086 	} else {
1087 		sev_es_tmr = NULL;
1088 		dev_warn(sev->dev,
1089 			 "SEV: TMR allocation failed, SEV-ES support unavailable\n");
1090 	}
1091 
1092 	/* Initialize the platform */
1093 	rc = sev_platform_init(&error);
1094 	if (rc && (error == SEV_RET_SECURE_DATA_INVALID)) {
1095 		/*
1096 		 * INIT command returned an integrity check failure
1097 		 * status code, meaning that firmware load and
1098 		 * validation of SEV related persistent data has
1099 		 * failed and persistent state has been erased.
1100 		 * Retrying INIT command here should succeed.
1101 		 */
1102 		dev_dbg(sev->dev, "SEV: retrying INIT command");
1103 		rc = sev_platform_init(&error);
1104 	}
1105 
1106 	if (rc) {
1107 		dev_err(sev->dev, "SEV: failed to INIT error %#x\n", error);
1108 		return;
1109 	}
1110 
1111 	dev_info(sev->dev, "SEV API:%d.%d build:%d\n", sev->api_major,
1112 		 sev->api_minor, sev->build);
1113 
1114 	return;
1115 
1116 err:
1117 	psp_master->sev_data = NULL;
1118 }
1119 
1120 void sev_pci_exit(void)
1121 {
1122 	struct sev_device *sev = psp_master->sev_data;
1123 
1124 	if (!sev)
1125 		return;
1126 
1127 	sev_firmware_shutdown(sev);
1128 }
1129