xref: /openbmc/linux/drivers/crypto/ccp/sev-dev.c (revision fb574682)
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 
25 #include <asm/smp.h>
26 
27 #include "psp-dev.h"
28 #include "sev-dev.h"
29 
30 #define DEVICE_NAME		"sev"
31 #define SEV_FW_FILE		"amd/sev.fw"
32 #define SEV_FW_NAME_SIZE	64
33 
34 static DEFINE_MUTEX(sev_cmd_mutex);
35 static struct sev_misc_dev *misc_dev;
36 
37 static int psp_cmd_timeout = 100;
38 module_param(psp_cmd_timeout, int, 0644);
39 MODULE_PARM_DESC(psp_cmd_timeout, " default timeout value, in seconds, for PSP commands");
40 
41 static int psp_probe_timeout = 5;
42 module_param(psp_probe_timeout, int, 0644);
43 MODULE_PARM_DESC(psp_probe_timeout, " default timeout value, in seconds, during PSP device probe");
44 
45 static bool psp_dead;
46 static int psp_timeout;
47 
48 /* Trusted Memory Region (TMR):
49  *   The TMR is a 1MB area that must be 1MB aligned.  Use the page allocator
50  *   to allocate the memory, which will return aligned memory for the specified
51  *   allocation order.
52  */
53 #define SEV_ES_TMR_SIZE		(1024 * 1024)
54 static void *sev_es_tmr;
55 
56 static inline bool sev_version_greater_or_equal(u8 maj, u8 min)
57 {
58 	struct sev_device *sev = psp_master->sev_data;
59 
60 	if (sev->api_major > maj)
61 		return true;
62 
63 	if (sev->api_major == maj && sev->api_minor >= min)
64 		return true;
65 
66 	return false;
67 }
68 
69 static void sev_irq_handler(int irq, void *data, unsigned int status)
70 {
71 	struct sev_device *sev = data;
72 	int reg;
73 
74 	/* Check if it is command completion: */
75 	if (!(status & SEV_CMD_COMPLETE))
76 		return;
77 
78 	/* Check if it is SEV command completion: */
79 	reg = ioread32(sev->io_regs + sev->vdata->cmdresp_reg);
80 	if (reg & PSP_CMDRESP_RESP) {
81 		sev->int_rcvd = 1;
82 		wake_up(&sev->int_queue);
83 	}
84 }
85 
86 static int sev_wait_cmd_ioc(struct sev_device *sev,
87 			    unsigned int *reg, unsigned int timeout)
88 {
89 	int ret;
90 
91 	ret = wait_event_timeout(sev->int_queue,
92 			sev->int_rcvd, timeout * HZ);
93 	if (!ret)
94 		return -ETIMEDOUT;
95 
96 	*reg = ioread32(sev->io_regs + sev->vdata->cmdresp_reg);
97 
98 	return 0;
99 }
100 
101 static int sev_cmd_buffer_len(int cmd)
102 {
103 	switch (cmd) {
104 	case SEV_CMD_INIT:			return sizeof(struct sev_data_init);
105 	case SEV_CMD_PLATFORM_STATUS:		return sizeof(struct sev_user_data_status);
106 	case SEV_CMD_PEK_CSR:			return sizeof(struct sev_data_pek_csr);
107 	case SEV_CMD_PEK_CERT_IMPORT:		return sizeof(struct sev_data_pek_cert_import);
108 	case SEV_CMD_PDH_CERT_EXPORT:		return sizeof(struct sev_data_pdh_cert_export);
109 	case SEV_CMD_LAUNCH_START:		return sizeof(struct sev_data_launch_start);
110 	case SEV_CMD_LAUNCH_UPDATE_DATA:	return sizeof(struct sev_data_launch_update_data);
111 	case SEV_CMD_LAUNCH_UPDATE_VMSA:	return sizeof(struct sev_data_launch_update_vmsa);
112 	case SEV_CMD_LAUNCH_FINISH:		return sizeof(struct sev_data_launch_finish);
113 	case SEV_CMD_LAUNCH_MEASURE:		return sizeof(struct sev_data_launch_measure);
114 	case SEV_CMD_ACTIVATE:			return sizeof(struct sev_data_activate);
115 	case SEV_CMD_DEACTIVATE:		return sizeof(struct sev_data_deactivate);
116 	case SEV_CMD_DECOMMISSION:		return sizeof(struct sev_data_decommission);
117 	case SEV_CMD_GUEST_STATUS:		return sizeof(struct sev_data_guest_status);
118 	case SEV_CMD_DBG_DECRYPT:		return sizeof(struct sev_data_dbg);
119 	case SEV_CMD_DBG_ENCRYPT:		return sizeof(struct sev_data_dbg);
120 	case SEV_CMD_SEND_START:		return sizeof(struct sev_data_send_start);
121 	case SEV_CMD_SEND_UPDATE_DATA:		return sizeof(struct sev_data_send_update_data);
122 	case SEV_CMD_SEND_UPDATE_VMSA:		return sizeof(struct sev_data_send_update_vmsa);
123 	case SEV_CMD_SEND_FINISH:		return sizeof(struct sev_data_send_finish);
124 	case SEV_CMD_RECEIVE_START:		return sizeof(struct sev_data_receive_start);
125 	case SEV_CMD_RECEIVE_FINISH:		return sizeof(struct sev_data_receive_finish);
126 	case SEV_CMD_RECEIVE_UPDATE_DATA:	return sizeof(struct sev_data_receive_update_data);
127 	case SEV_CMD_RECEIVE_UPDATE_VMSA:	return sizeof(struct sev_data_receive_update_vmsa);
128 	case SEV_CMD_LAUNCH_UPDATE_SECRET:	return sizeof(struct sev_data_launch_secret);
129 	case SEV_CMD_DOWNLOAD_FIRMWARE:		return sizeof(struct sev_data_download_firmware);
130 	case SEV_CMD_GET_ID:			return sizeof(struct sev_data_get_id);
131 	default:				return 0;
132 	}
133 
134 	return 0;
135 }
136 
137 static int __sev_do_cmd_locked(int cmd, void *data, int *psp_ret)
138 {
139 	struct psp_device *psp = psp_master;
140 	struct sev_device *sev;
141 	unsigned int phys_lsb, phys_msb;
142 	unsigned int reg, ret = 0;
143 
144 	if (!psp || !psp->sev_data)
145 		return -ENODEV;
146 
147 	if (psp_dead)
148 		return -EBUSY;
149 
150 	sev = psp->sev_data;
151 
152 	/* Get the physical address of the command buffer */
153 	phys_lsb = data ? lower_32_bits(__psp_pa(data)) : 0;
154 	phys_msb = data ? upper_32_bits(__psp_pa(data)) : 0;
155 
156 	dev_dbg(sev->dev, "sev command id %#x buffer 0x%08x%08x timeout %us\n",
157 		cmd, phys_msb, phys_lsb, psp_timeout);
158 
159 	print_hex_dump_debug("(in):  ", DUMP_PREFIX_OFFSET, 16, 2, data,
160 			     sev_cmd_buffer_len(cmd), false);
161 
162 	iowrite32(phys_lsb, sev->io_regs + sev->vdata->cmdbuff_addr_lo_reg);
163 	iowrite32(phys_msb, sev->io_regs + sev->vdata->cmdbuff_addr_hi_reg);
164 
165 	sev->int_rcvd = 0;
166 
167 	reg = cmd;
168 	reg <<= SEV_CMDRESP_CMD_SHIFT;
169 	reg |= SEV_CMDRESP_IOC;
170 	iowrite32(reg, sev->io_regs + sev->vdata->cmdresp_reg);
171 
172 	/* wait for command completion */
173 	ret = sev_wait_cmd_ioc(sev, &reg, psp_timeout);
174 	if (ret) {
175 		if (psp_ret)
176 			*psp_ret = 0;
177 
178 		dev_err(sev->dev, "sev command %#x timed out, disabling PSP\n", cmd);
179 		psp_dead = true;
180 
181 		return ret;
182 	}
183 
184 	psp_timeout = psp_cmd_timeout;
185 
186 	if (psp_ret)
187 		*psp_ret = reg & PSP_CMDRESP_ERR_MASK;
188 
189 	if (reg & PSP_CMDRESP_ERR_MASK) {
190 		dev_dbg(sev->dev, "sev command %#x failed (%#010x)\n",
191 			cmd, reg & PSP_CMDRESP_ERR_MASK);
192 		ret = -EIO;
193 	}
194 
195 	print_hex_dump_debug("(out): ", DUMP_PREFIX_OFFSET, 16, 2, data,
196 			     sev_cmd_buffer_len(cmd), false);
197 
198 	return ret;
199 }
200 
201 static int sev_do_cmd(int cmd, void *data, int *psp_ret)
202 {
203 	int rc;
204 
205 	mutex_lock(&sev_cmd_mutex);
206 	rc = __sev_do_cmd_locked(cmd, data, psp_ret);
207 	mutex_unlock(&sev_cmd_mutex);
208 
209 	return rc;
210 }
211 
212 static int __sev_platform_init_locked(int *error)
213 {
214 	struct psp_device *psp = psp_master;
215 	struct sev_device *sev;
216 	int rc = 0;
217 
218 	if (!psp || !psp->sev_data)
219 		return -ENODEV;
220 
221 	sev = psp->sev_data;
222 
223 	if (sev->state == SEV_STATE_INIT)
224 		return 0;
225 
226 	if (sev_es_tmr) {
227 		u64 tmr_pa;
228 
229 		/*
230 		 * Do not include the encryption mask on the physical
231 		 * address of the TMR (firmware should clear it anyway).
232 		 */
233 		tmr_pa = __pa(sev_es_tmr);
234 
235 		sev->init_cmd_buf.flags |= SEV_INIT_FLAGS_SEV_ES;
236 		sev->init_cmd_buf.tmr_address = tmr_pa;
237 		sev->init_cmd_buf.tmr_len = SEV_ES_TMR_SIZE;
238 	}
239 
240 	rc = __sev_do_cmd_locked(SEV_CMD_INIT, &sev->init_cmd_buf, error);
241 	if (rc)
242 		return rc;
243 
244 	sev->state = SEV_STATE_INIT;
245 
246 	/* Prepare for first SEV guest launch after INIT */
247 	wbinvd_on_all_cpus();
248 	rc = __sev_do_cmd_locked(SEV_CMD_DF_FLUSH, NULL, error);
249 	if (rc)
250 		return rc;
251 
252 	dev_dbg(sev->dev, "SEV firmware initialized\n");
253 
254 	return rc;
255 }
256 
257 int sev_platform_init(int *error)
258 {
259 	int rc;
260 
261 	mutex_lock(&sev_cmd_mutex);
262 	rc = __sev_platform_init_locked(error);
263 	mutex_unlock(&sev_cmd_mutex);
264 
265 	return rc;
266 }
267 EXPORT_SYMBOL_GPL(sev_platform_init);
268 
269 static int __sev_platform_shutdown_locked(int *error)
270 {
271 	struct sev_device *sev = psp_master->sev_data;
272 	int ret;
273 
274 	ret = __sev_do_cmd_locked(SEV_CMD_SHUTDOWN, NULL, error);
275 	if (ret)
276 		return ret;
277 
278 	sev->state = SEV_STATE_UNINIT;
279 	dev_dbg(sev->dev, "SEV firmware shutdown\n");
280 
281 	return ret;
282 }
283 
284 static int sev_platform_shutdown(int *error)
285 {
286 	int rc;
287 
288 	mutex_lock(&sev_cmd_mutex);
289 	rc = __sev_platform_shutdown_locked(NULL);
290 	mutex_unlock(&sev_cmd_mutex);
291 
292 	return rc;
293 }
294 
295 static int sev_get_platform_state(int *state, int *error)
296 {
297 	struct sev_device *sev = psp_master->sev_data;
298 	int rc;
299 
300 	rc = __sev_do_cmd_locked(SEV_CMD_PLATFORM_STATUS,
301 				 &sev->status_cmd_buf, error);
302 	if (rc)
303 		return rc;
304 
305 	*state = sev->status_cmd_buf.state;
306 	return rc;
307 }
308 
309 static int sev_ioctl_do_reset(struct sev_issue_cmd *argp, bool writable)
310 {
311 	int state, rc;
312 
313 	if (!writable)
314 		return -EPERM;
315 
316 	/*
317 	 * The SEV spec requires that FACTORY_RESET must be issued in
318 	 * UNINIT state. Before we go further lets check if any guest is
319 	 * active.
320 	 *
321 	 * If FW is in WORKING state then deny the request otherwise issue
322 	 * SHUTDOWN command do INIT -> UNINIT before issuing the FACTORY_RESET.
323 	 *
324 	 */
325 	rc = sev_get_platform_state(&state, &argp->error);
326 	if (rc)
327 		return rc;
328 
329 	if (state == SEV_STATE_WORKING)
330 		return -EBUSY;
331 
332 	if (state == SEV_STATE_INIT) {
333 		rc = __sev_platform_shutdown_locked(&argp->error);
334 		if (rc)
335 			return rc;
336 	}
337 
338 	return __sev_do_cmd_locked(SEV_CMD_FACTORY_RESET, NULL, &argp->error);
339 }
340 
341 static int sev_ioctl_do_platform_status(struct sev_issue_cmd *argp)
342 {
343 	struct sev_device *sev = psp_master->sev_data;
344 	struct sev_user_data_status *data = &sev->status_cmd_buf;
345 	int ret;
346 
347 	ret = __sev_do_cmd_locked(SEV_CMD_PLATFORM_STATUS, data, &argp->error);
348 	if (ret)
349 		return ret;
350 
351 	if (copy_to_user((void __user *)argp->data, data, sizeof(*data)))
352 		ret = -EFAULT;
353 
354 	return ret;
355 }
356 
357 static int sev_ioctl_do_pek_pdh_gen(int cmd, struct sev_issue_cmd *argp, bool writable)
358 {
359 	struct sev_device *sev = psp_master->sev_data;
360 	int rc;
361 
362 	if (!writable)
363 		return -EPERM;
364 
365 	if (sev->state == SEV_STATE_UNINIT) {
366 		rc = __sev_platform_init_locked(&argp->error);
367 		if (rc)
368 			return rc;
369 	}
370 
371 	return __sev_do_cmd_locked(cmd, NULL, &argp->error);
372 }
373 
374 static int sev_ioctl_do_pek_csr(struct sev_issue_cmd *argp, bool writable)
375 {
376 	struct sev_device *sev = psp_master->sev_data;
377 	struct sev_user_data_pek_csr input;
378 	struct sev_data_pek_csr *data;
379 	void *blob = NULL;
380 	int ret;
381 
382 	if (!writable)
383 		return -EPERM;
384 
385 	if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
386 		return -EFAULT;
387 
388 	data = kzalloc(sizeof(*data), GFP_KERNEL);
389 	if (!data)
390 		return -ENOMEM;
391 
392 	/* userspace wants to query CSR length */
393 	if (!input.address || !input.length)
394 		goto cmd;
395 
396 	/* allocate a physically contiguous buffer to store the CSR blob */
397 	if (input.length > SEV_FW_BLOB_MAX_SIZE) {
398 		ret = -EFAULT;
399 		goto e_free;
400 	}
401 
402 	blob = kmalloc(input.length, GFP_KERNEL);
403 	if (!blob) {
404 		ret = -ENOMEM;
405 		goto e_free;
406 	}
407 
408 	data->address = __psp_pa(blob);
409 	data->len = input.length;
410 
411 cmd:
412 	if (sev->state == SEV_STATE_UNINIT) {
413 		ret = __sev_platform_init_locked(&argp->error);
414 		if (ret)
415 			goto e_free_blob;
416 	}
417 
418 	ret = __sev_do_cmd_locked(SEV_CMD_PEK_CSR, data, &argp->error);
419 
420 	 /* If we query the CSR length, FW responded with expected data. */
421 	input.length = data->len;
422 
423 	if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) {
424 		ret = -EFAULT;
425 		goto e_free_blob;
426 	}
427 
428 	if (blob) {
429 		if (copy_to_user((void __user *)input.address, blob, input.length))
430 			ret = -EFAULT;
431 	}
432 
433 e_free_blob:
434 	kfree(blob);
435 e_free:
436 	kfree(data);
437 	return ret;
438 }
439 
440 void *psp_copy_user_blob(u64 __user uaddr, u32 len)
441 {
442 	if (!uaddr || !len)
443 		return ERR_PTR(-EINVAL);
444 
445 	/* verify that blob length does not exceed our limit */
446 	if (len > SEV_FW_BLOB_MAX_SIZE)
447 		return ERR_PTR(-EINVAL);
448 
449 	return memdup_user((void __user *)(uintptr_t)uaddr, len);
450 }
451 EXPORT_SYMBOL_GPL(psp_copy_user_blob);
452 
453 static int sev_get_api_version(void)
454 {
455 	struct sev_device *sev = psp_master->sev_data;
456 	struct sev_user_data_status *status;
457 	int error = 0, ret;
458 
459 	status = &sev->status_cmd_buf;
460 	ret = sev_platform_status(status, &error);
461 	if (ret) {
462 		dev_err(sev->dev,
463 			"SEV: failed to get status. Error: %#x\n", error);
464 		return 1;
465 	}
466 
467 	sev->api_major = status->api_major;
468 	sev->api_minor = status->api_minor;
469 	sev->build = status->build;
470 	sev->state = status->state;
471 
472 	return 0;
473 }
474 
475 static int sev_get_firmware(struct device *dev,
476 			    const struct firmware **firmware)
477 {
478 	char fw_name_specific[SEV_FW_NAME_SIZE];
479 	char fw_name_subset[SEV_FW_NAME_SIZE];
480 
481 	snprintf(fw_name_specific, sizeof(fw_name_specific),
482 		 "amd/amd_sev_fam%.2xh_model%.2xh.sbin",
483 		 boot_cpu_data.x86, boot_cpu_data.x86_model);
484 
485 	snprintf(fw_name_subset, sizeof(fw_name_subset),
486 		 "amd/amd_sev_fam%.2xh_model%.1xxh.sbin",
487 		 boot_cpu_data.x86, (boot_cpu_data.x86_model & 0xf0) >> 4);
488 
489 	/* Check for SEV FW for a particular model.
490 	 * Ex. amd_sev_fam17h_model00h.sbin for Family 17h Model 00h
491 	 *
492 	 * or
493 	 *
494 	 * Check for SEV FW common to a subset of models.
495 	 * Ex. amd_sev_fam17h_model0xh.sbin for
496 	 *     Family 17h Model 00h -- Family 17h Model 0Fh
497 	 *
498 	 * or
499 	 *
500 	 * Fall-back to using generic name: sev.fw
501 	 */
502 	if ((firmware_request_nowarn(firmware, fw_name_specific, dev) >= 0) ||
503 	    (firmware_request_nowarn(firmware, fw_name_subset, dev) >= 0) ||
504 	    (firmware_request_nowarn(firmware, SEV_FW_FILE, dev) >= 0))
505 		return 0;
506 
507 	return -ENOENT;
508 }
509 
510 /* Don't fail if SEV FW couldn't be updated. Continue with existing SEV FW */
511 static int sev_update_firmware(struct device *dev)
512 {
513 	struct sev_data_download_firmware *data;
514 	const struct firmware *firmware;
515 	int ret, error, order;
516 	struct page *p;
517 	u64 data_size;
518 
519 	if (sev_get_firmware(dev, &firmware) == -ENOENT) {
520 		dev_dbg(dev, "No SEV firmware file present\n");
521 		return -1;
522 	}
523 
524 	/*
525 	 * SEV FW expects the physical address given to it to be 32
526 	 * byte aligned. Memory allocated has structure placed at the
527 	 * beginning followed by the firmware being passed to the SEV
528 	 * FW. Allocate enough memory for data structure + alignment
529 	 * padding + SEV FW.
530 	 */
531 	data_size = ALIGN(sizeof(struct sev_data_download_firmware), 32);
532 
533 	order = get_order(firmware->size + data_size);
534 	p = alloc_pages(GFP_KERNEL, order);
535 	if (!p) {
536 		ret = -1;
537 		goto fw_err;
538 	}
539 
540 	/*
541 	 * Copy firmware data to a kernel allocated contiguous
542 	 * memory region.
543 	 */
544 	data = page_address(p);
545 	memcpy(page_address(p) + data_size, firmware->data, firmware->size);
546 
547 	data->address = __psp_pa(page_address(p) + data_size);
548 	data->len = firmware->size;
549 
550 	ret = sev_do_cmd(SEV_CMD_DOWNLOAD_FIRMWARE, data, &error);
551 	if (ret)
552 		dev_dbg(dev, "Failed to update SEV firmware: %#x\n", error);
553 	else
554 		dev_info(dev, "SEV firmware update successful\n");
555 
556 	__free_pages(p, order);
557 
558 fw_err:
559 	release_firmware(firmware);
560 
561 	return ret;
562 }
563 
564 static int sev_ioctl_do_pek_import(struct sev_issue_cmd *argp, bool writable)
565 {
566 	struct sev_device *sev = psp_master->sev_data;
567 	struct sev_user_data_pek_cert_import input;
568 	struct sev_data_pek_cert_import *data;
569 	void *pek_blob, *oca_blob;
570 	int ret;
571 
572 	if (!writable)
573 		return -EPERM;
574 
575 	if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
576 		return -EFAULT;
577 
578 	data = kzalloc(sizeof(*data), GFP_KERNEL);
579 	if (!data)
580 		return -ENOMEM;
581 
582 	/* copy PEK certificate blobs from userspace */
583 	pek_blob = psp_copy_user_blob(input.pek_cert_address, input.pek_cert_len);
584 	if (IS_ERR(pek_blob)) {
585 		ret = PTR_ERR(pek_blob);
586 		goto e_free;
587 	}
588 
589 	data->pek_cert_address = __psp_pa(pek_blob);
590 	data->pek_cert_len = input.pek_cert_len;
591 
592 	/* copy PEK certificate blobs from userspace */
593 	oca_blob = psp_copy_user_blob(input.oca_cert_address, input.oca_cert_len);
594 	if (IS_ERR(oca_blob)) {
595 		ret = PTR_ERR(oca_blob);
596 		goto e_free_pek;
597 	}
598 
599 	data->oca_cert_address = __psp_pa(oca_blob);
600 	data->oca_cert_len = input.oca_cert_len;
601 
602 	/* If platform is not in INIT state then transition it to INIT */
603 	if (sev->state != SEV_STATE_INIT) {
604 		ret = __sev_platform_init_locked(&argp->error);
605 		if (ret)
606 			goto e_free_oca;
607 	}
608 
609 	ret = __sev_do_cmd_locked(SEV_CMD_PEK_CERT_IMPORT, data, &argp->error);
610 
611 e_free_oca:
612 	kfree(oca_blob);
613 e_free_pek:
614 	kfree(pek_blob);
615 e_free:
616 	kfree(data);
617 	return ret;
618 }
619 
620 static int sev_ioctl_do_get_id2(struct sev_issue_cmd *argp)
621 {
622 	struct sev_user_data_get_id2 input;
623 	struct sev_data_get_id *data;
624 	void *id_blob = NULL;
625 	int ret;
626 
627 	/* SEV GET_ID is available from SEV API v0.16 and up */
628 	if (!sev_version_greater_or_equal(0, 16))
629 		return -ENOTSUPP;
630 
631 	if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
632 		return -EFAULT;
633 
634 	data = kzalloc(sizeof(*data), GFP_KERNEL);
635 	if (!data)
636 		return -ENOMEM;
637 
638 	if (input.address && input.length) {
639 		id_blob = kmalloc(input.length, GFP_KERNEL);
640 		if (!id_blob) {
641 			kfree(data);
642 			return -ENOMEM;
643 		}
644 
645 		data->address = __psp_pa(id_blob);
646 		data->len = input.length;
647 	}
648 
649 	ret = __sev_do_cmd_locked(SEV_CMD_GET_ID, data, &argp->error);
650 
651 	/*
652 	 * Firmware will return the length of the ID value (either the minimum
653 	 * required length or the actual length written), return it to the user.
654 	 */
655 	input.length = data->len;
656 
657 	if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) {
658 		ret = -EFAULT;
659 		goto e_free;
660 	}
661 
662 	if (id_blob) {
663 		if (copy_to_user((void __user *)input.address,
664 				 id_blob, data->len)) {
665 			ret = -EFAULT;
666 			goto e_free;
667 		}
668 	}
669 
670 e_free:
671 	kfree(id_blob);
672 	kfree(data);
673 
674 	return ret;
675 }
676 
677 static int sev_ioctl_do_get_id(struct sev_issue_cmd *argp)
678 {
679 	struct sev_data_get_id *data;
680 	u64 data_size, user_size;
681 	void *id_blob, *mem;
682 	int ret;
683 
684 	/* SEV GET_ID available from SEV API v0.16 and up */
685 	if (!sev_version_greater_or_equal(0, 16))
686 		return -ENOTSUPP;
687 
688 	/* SEV FW expects the buffer it fills with the ID to be
689 	 * 8-byte aligned. Memory allocated should be enough to
690 	 * hold data structure + alignment padding + memory
691 	 * where SEV FW writes the ID.
692 	 */
693 	data_size = ALIGN(sizeof(struct sev_data_get_id), 8);
694 	user_size = sizeof(struct sev_user_data_get_id);
695 
696 	mem = kzalloc(data_size + user_size, GFP_KERNEL);
697 	if (!mem)
698 		return -ENOMEM;
699 
700 	data = mem;
701 	id_blob = mem + data_size;
702 
703 	data->address = __psp_pa(id_blob);
704 	data->len = user_size;
705 
706 	ret = __sev_do_cmd_locked(SEV_CMD_GET_ID, data, &argp->error);
707 	if (!ret) {
708 		if (copy_to_user((void __user *)argp->data, id_blob, data->len))
709 			ret = -EFAULT;
710 	}
711 
712 	kfree(mem);
713 
714 	return ret;
715 }
716 
717 static int sev_ioctl_do_pdh_export(struct sev_issue_cmd *argp, bool writable)
718 {
719 	struct sev_device *sev = psp_master->sev_data;
720 	struct sev_user_data_pdh_cert_export input;
721 	void *pdh_blob = NULL, *cert_blob = NULL;
722 	struct sev_data_pdh_cert_export *data;
723 	int ret;
724 
725 	/* If platform is not in INIT state then transition it to INIT. */
726 	if (sev->state != SEV_STATE_INIT) {
727 		if (!writable)
728 			return -EPERM;
729 
730 		ret = __sev_platform_init_locked(&argp->error);
731 		if (ret)
732 			return ret;
733 	}
734 
735 	if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
736 		return -EFAULT;
737 
738 	data = kzalloc(sizeof(*data), GFP_KERNEL);
739 	if (!data)
740 		return -ENOMEM;
741 
742 	/* Userspace wants to query the certificate length. */
743 	if (!input.pdh_cert_address ||
744 	    !input.pdh_cert_len ||
745 	    !input.cert_chain_address)
746 		goto cmd;
747 
748 	/* Allocate a physically contiguous buffer to store the PDH blob. */
749 	if (input.pdh_cert_len > SEV_FW_BLOB_MAX_SIZE) {
750 		ret = -EFAULT;
751 		goto e_free;
752 	}
753 
754 	/* Allocate a physically contiguous buffer to store the cert chain blob. */
755 	if (input.cert_chain_len > SEV_FW_BLOB_MAX_SIZE) {
756 		ret = -EFAULT;
757 		goto e_free;
758 	}
759 
760 	pdh_blob = kmalloc(input.pdh_cert_len, GFP_KERNEL);
761 	if (!pdh_blob) {
762 		ret = -ENOMEM;
763 		goto e_free;
764 	}
765 
766 	data->pdh_cert_address = __psp_pa(pdh_blob);
767 	data->pdh_cert_len = input.pdh_cert_len;
768 
769 	cert_blob = kmalloc(input.cert_chain_len, GFP_KERNEL);
770 	if (!cert_blob) {
771 		ret = -ENOMEM;
772 		goto e_free_pdh;
773 	}
774 
775 	data->cert_chain_address = __psp_pa(cert_blob);
776 	data->cert_chain_len = input.cert_chain_len;
777 
778 cmd:
779 	ret = __sev_do_cmd_locked(SEV_CMD_PDH_CERT_EXPORT, data, &argp->error);
780 
781 	/* If we query the length, FW responded with expected data. */
782 	input.cert_chain_len = data->cert_chain_len;
783 	input.pdh_cert_len = data->pdh_cert_len;
784 
785 	if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) {
786 		ret = -EFAULT;
787 		goto e_free_cert;
788 	}
789 
790 	if (pdh_blob) {
791 		if (copy_to_user((void __user *)input.pdh_cert_address,
792 				 pdh_blob, input.pdh_cert_len)) {
793 			ret = -EFAULT;
794 			goto e_free_cert;
795 		}
796 	}
797 
798 	if (cert_blob) {
799 		if (copy_to_user((void __user *)input.cert_chain_address,
800 				 cert_blob, input.cert_chain_len))
801 			ret = -EFAULT;
802 	}
803 
804 e_free_cert:
805 	kfree(cert_blob);
806 e_free_pdh:
807 	kfree(pdh_blob);
808 e_free:
809 	kfree(data);
810 	return ret;
811 }
812 
813 static long sev_ioctl(struct file *file, unsigned int ioctl, unsigned long arg)
814 {
815 	void __user *argp = (void __user *)arg;
816 	struct sev_issue_cmd input;
817 	int ret = -EFAULT;
818 	bool writable = file->f_mode & FMODE_WRITE;
819 
820 	if (!psp_master || !psp_master->sev_data)
821 		return -ENODEV;
822 
823 	if (ioctl != SEV_ISSUE_CMD)
824 		return -EINVAL;
825 
826 	if (copy_from_user(&input, argp, sizeof(struct sev_issue_cmd)))
827 		return -EFAULT;
828 
829 	if (input.cmd > SEV_MAX)
830 		return -EINVAL;
831 
832 	mutex_lock(&sev_cmd_mutex);
833 
834 	switch (input.cmd) {
835 
836 	case SEV_FACTORY_RESET:
837 		ret = sev_ioctl_do_reset(&input, writable);
838 		break;
839 	case SEV_PLATFORM_STATUS:
840 		ret = sev_ioctl_do_platform_status(&input);
841 		break;
842 	case SEV_PEK_GEN:
843 		ret = sev_ioctl_do_pek_pdh_gen(SEV_CMD_PEK_GEN, &input, writable);
844 		break;
845 	case SEV_PDH_GEN:
846 		ret = sev_ioctl_do_pek_pdh_gen(SEV_CMD_PDH_GEN, &input, writable);
847 		break;
848 	case SEV_PEK_CSR:
849 		ret = sev_ioctl_do_pek_csr(&input, writable);
850 		break;
851 	case SEV_PEK_CERT_IMPORT:
852 		ret = sev_ioctl_do_pek_import(&input, writable);
853 		break;
854 	case SEV_PDH_CERT_EXPORT:
855 		ret = sev_ioctl_do_pdh_export(&input, writable);
856 		break;
857 	case SEV_GET_ID:
858 		pr_warn_once("SEV_GET_ID command is deprecated, use SEV_GET_ID2\n");
859 		ret = sev_ioctl_do_get_id(&input);
860 		break;
861 	case SEV_GET_ID2:
862 		ret = sev_ioctl_do_get_id2(&input);
863 		break;
864 	default:
865 		ret = -EINVAL;
866 		goto out;
867 	}
868 
869 	if (copy_to_user(argp, &input, sizeof(struct sev_issue_cmd)))
870 		ret = -EFAULT;
871 out:
872 	mutex_unlock(&sev_cmd_mutex);
873 
874 	return ret;
875 }
876 
877 static const struct file_operations sev_fops = {
878 	.owner	= THIS_MODULE,
879 	.unlocked_ioctl = sev_ioctl,
880 };
881 
882 int sev_platform_status(struct sev_user_data_status *data, int *error)
883 {
884 	return sev_do_cmd(SEV_CMD_PLATFORM_STATUS, data, error);
885 }
886 EXPORT_SYMBOL_GPL(sev_platform_status);
887 
888 int sev_guest_deactivate(struct sev_data_deactivate *data, int *error)
889 {
890 	return sev_do_cmd(SEV_CMD_DEACTIVATE, data, error);
891 }
892 EXPORT_SYMBOL_GPL(sev_guest_deactivate);
893 
894 int sev_guest_activate(struct sev_data_activate *data, int *error)
895 {
896 	return sev_do_cmd(SEV_CMD_ACTIVATE, data, error);
897 }
898 EXPORT_SYMBOL_GPL(sev_guest_activate);
899 
900 int sev_guest_decommission(struct sev_data_decommission *data, int *error)
901 {
902 	return sev_do_cmd(SEV_CMD_DECOMMISSION, data, error);
903 }
904 EXPORT_SYMBOL_GPL(sev_guest_decommission);
905 
906 int sev_guest_df_flush(int *error)
907 {
908 	return sev_do_cmd(SEV_CMD_DF_FLUSH, NULL, error);
909 }
910 EXPORT_SYMBOL_GPL(sev_guest_df_flush);
911 
912 static void sev_exit(struct kref *ref)
913 {
914 	misc_deregister(&misc_dev->misc);
915 	kfree(misc_dev);
916 	misc_dev = NULL;
917 }
918 
919 static int sev_misc_init(struct sev_device *sev)
920 {
921 	struct device *dev = sev->dev;
922 	int ret;
923 
924 	/*
925 	 * SEV feature support can be detected on multiple devices but the SEV
926 	 * FW commands must be issued on the master. During probe, we do not
927 	 * know the master hence we create /dev/sev on the first device probe.
928 	 * sev_do_cmd() finds the right master device to which to issue the
929 	 * command to the firmware.
930 	 */
931 	if (!misc_dev) {
932 		struct miscdevice *misc;
933 
934 		misc_dev = kzalloc(sizeof(*misc_dev), GFP_KERNEL);
935 		if (!misc_dev)
936 			return -ENOMEM;
937 
938 		misc = &misc_dev->misc;
939 		misc->minor = MISC_DYNAMIC_MINOR;
940 		misc->name = DEVICE_NAME;
941 		misc->fops = &sev_fops;
942 
943 		ret = misc_register(misc);
944 		if (ret)
945 			return ret;
946 
947 		kref_init(&misc_dev->refcount);
948 	} else {
949 		kref_get(&misc_dev->refcount);
950 	}
951 
952 	init_waitqueue_head(&sev->int_queue);
953 	sev->misc = misc_dev;
954 	dev_dbg(dev, "registered SEV device\n");
955 
956 	return 0;
957 }
958 
959 int sev_dev_init(struct psp_device *psp)
960 {
961 	struct device *dev = psp->dev;
962 	struct sev_device *sev;
963 	int ret = -ENOMEM;
964 
965 	sev = devm_kzalloc(dev, sizeof(*sev), GFP_KERNEL);
966 	if (!sev)
967 		goto e_err;
968 
969 	psp->sev_data = sev;
970 
971 	sev->dev = dev;
972 	sev->psp = psp;
973 
974 	sev->io_regs = psp->io_regs;
975 
976 	sev->vdata = (struct sev_vdata *)psp->vdata->sev;
977 	if (!sev->vdata) {
978 		ret = -ENODEV;
979 		dev_err(dev, "sev: missing driver data\n");
980 		goto e_err;
981 	}
982 
983 	psp_set_sev_irq_handler(psp, sev_irq_handler, sev);
984 
985 	ret = sev_misc_init(sev);
986 	if (ret)
987 		goto e_irq;
988 
989 	dev_notice(dev, "sev enabled\n");
990 
991 	return 0;
992 
993 e_irq:
994 	psp_clear_sev_irq_handler(psp);
995 e_err:
996 	psp->sev_data = NULL;
997 
998 	dev_notice(dev, "sev initialization failed\n");
999 
1000 	return ret;
1001 }
1002 
1003 void sev_dev_destroy(struct psp_device *psp)
1004 {
1005 	struct sev_device *sev = psp->sev_data;
1006 
1007 	if (!sev)
1008 		return;
1009 
1010 	if (sev->misc)
1011 		kref_put(&misc_dev->refcount, sev_exit);
1012 
1013 	psp_clear_sev_irq_handler(psp);
1014 }
1015 
1016 int sev_issue_cmd_external_user(struct file *filep, unsigned int cmd,
1017 				void *data, int *error)
1018 {
1019 	if (!filep || filep->f_op != &sev_fops)
1020 		return -EBADF;
1021 
1022 	return sev_do_cmd(cmd, data, error);
1023 }
1024 EXPORT_SYMBOL_GPL(sev_issue_cmd_external_user);
1025 
1026 void sev_pci_init(void)
1027 {
1028 	struct sev_device *sev = psp_master->sev_data;
1029 	struct page *tmr_page;
1030 	int error, rc;
1031 
1032 	if (!sev)
1033 		return;
1034 
1035 	psp_timeout = psp_probe_timeout;
1036 
1037 	if (sev_get_api_version())
1038 		goto err;
1039 
1040 	/*
1041 	 * If platform is not in UNINIT state then firmware upgrade and/or
1042 	 * platform INIT command will fail. These command require UNINIT state.
1043 	 *
1044 	 * In a normal boot we should never run into case where the firmware
1045 	 * is not in UNINIT state on boot. But in case of kexec boot, a reboot
1046 	 * may not go through a typical shutdown sequence and may leave the
1047 	 * firmware in INIT or WORKING state.
1048 	 */
1049 
1050 	if (sev->state != SEV_STATE_UNINIT) {
1051 		sev_platform_shutdown(NULL);
1052 		sev->state = SEV_STATE_UNINIT;
1053 	}
1054 
1055 	if (sev_version_greater_or_equal(0, 15) &&
1056 	    sev_update_firmware(sev->dev) == 0)
1057 		sev_get_api_version();
1058 
1059 	/* Obtain the TMR memory area for SEV-ES use */
1060 	tmr_page = alloc_pages(GFP_KERNEL, get_order(SEV_ES_TMR_SIZE));
1061 	if (tmr_page) {
1062 		sev_es_tmr = page_address(tmr_page);
1063 	} else {
1064 		sev_es_tmr = NULL;
1065 		dev_warn(sev->dev,
1066 			 "SEV: TMR allocation failed, SEV-ES support unavailable\n");
1067 	}
1068 
1069 	/* Initialize the platform */
1070 	rc = sev_platform_init(&error);
1071 	if (rc && (error == SEV_RET_SECURE_DATA_INVALID)) {
1072 		/*
1073 		 * INIT command returned an integrity check failure
1074 		 * status code, meaning that firmware load and
1075 		 * validation of SEV related persistent data has
1076 		 * failed and persistent state has been erased.
1077 		 * Retrying INIT command here should succeed.
1078 		 */
1079 		dev_dbg(sev->dev, "SEV: retrying INIT command");
1080 		rc = sev_platform_init(&error);
1081 	}
1082 
1083 	if (rc) {
1084 		dev_err(sev->dev, "SEV: failed to INIT error %#x\n", error);
1085 		return;
1086 	}
1087 
1088 	dev_info(sev->dev, "SEV API:%d.%d build:%d\n", sev->api_major,
1089 		 sev->api_minor, sev->build);
1090 
1091 	return;
1092 
1093 err:
1094 	psp_master->sev_data = NULL;
1095 }
1096 
1097 void sev_pci_exit(void)
1098 {
1099 	if (!psp_master->sev_data)
1100 		return;
1101 
1102 	sev_platform_shutdown(NULL);
1103 
1104 	if (sev_es_tmr) {
1105 		/* The TMR area was encrypted, flush it from the cache */
1106 		wbinvd_on_all_cpus();
1107 
1108 		free_pages((unsigned long)sev_es_tmr,
1109 			   get_order(SEV_ES_TMR_SIZE));
1110 		sev_es_tmr = NULL;
1111 	}
1112 }
1113