xref: /openbmc/linux/drivers/crypto/ccp/sev-dev.c (revision 06676aa1)
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 	ret = __sev_do_cmd_locked(SEV_CMD_SHUTDOWN, NULL, error);
304 	if (ret)
305 		return ret;
306 
307 	sev->state = SEV_STATE_UNINIT;
308 	dev_dbg(sev->dev, "SEV firmware shutdown\n");
309 
310 	return ret;
311 }
312 
313 static int sev_platform_shutdown(int *error)
314 {
315 	int rc;
316 
317 	mutex_lock(&sev_cmd_mutex);
318 	rc = __sev_platform_shutdown_locked(NULL);
319 	mutex_unlock(&sev_cmd_mutex);
320 
321 	return rc;
322 }
323 
324 static int sev_get_platform_state(int *state, int *error)
325 {
326 	struct sev_user_data_status data;
327 	int rc;
328 
329 	rc = __sev_do_cmd_locked(SEV_CMD_PLATFORM_STATUS, &data, error);
330 	if (rc)
331 		return rc;
332 
333 	*state = data.state;
334 	return rc;
335 }
336 
337 static int sev_ioctl_do_reset(struct sev_issue_cmd *argp, bool writable)
338 {
339 	int state, rc;
340 
341 	if (!writable)
342 		return -EPERM;
343 
344 	/*
345 	 * The SEV spec requires that FACTORY_RESET must be issued in
346 	 * UNINIT state. Before we go further lets check if any guest is
347 	 * active.
348 	 *
349 	 * If FW is in WORKING state then deny the request otherwise issue
350 	 * SHUTDOWN command do INIT -> UNINIT before issuing the FACTORY_RESET.
351 	 *
352 	 */
353 	rc = sev_get_platform_state(&state, &argp->error);
354 	if (rc)
355 		return rc;
356 
357 	if (state == SEV_STATE_WORKING)
358 		return -EBUSY;
359 
360 	if (state == SEV_STATE_INIT) {
361 		rc = __sev_platform_shutdown_locked(&argp->error);
362 		if (rc)
363 			return rc;
364 	}
365 
366 	return __sev_do_cmd_locked(SEV_CMD_FACTORY_RESET, NULL, &argp->error);
367 }
368 
369 static int sev_ioctl_do_platform_status(struct sev_issue_cmd *argp)
370 {
371 	struct sev_user_data_status data;
372 	int ret;
373 
374 	ret = __sev_do_cmd_locked(SEV_CMD_PLATFORM_STATUS, &data, &argp->error);
375 	if (ret)
376 		return ret;
377 
378 	if (copy_to_user((void __user *)argp->data, &data, sizeof(data)))
379 		ret = -EFAULT;
380 
381 	return ret;
382 }
383 
384 static int sev_ioctl_do_pek_pdh_gen(int cmd, struct sev_issue_cmd *argp, bool writable)
385 {
386 	struct sev_device *sev = psp_master->sev_data;
387 	int rc;
388 
389 	if (!writable)
390 		return -EPERM;
391 
392 	if (sev->state == SEV_STATE_UNINIT) {
393 		rc = __sev_platform_init_locked(&argp->error);
394 		if (rc)
395 			return rc;
396 	}
397 
398 	return __sev_do_cmd_locked(cmd, NULL, &argp->error);
399 }
400 
401 static int sev_ioctl_do_pek_csr(struct sev_issue_cmd *argp, bool writable)
402 {
403 	struct sev_device *sev = psp_master->sev_data;
404 	struct sev_user_data_pek_csr input;
405 	struct sev_data_pek_csr data;
406 	void __user *input_address;
407 	void *blob = NULL;
408 	int ret;
409 
410 	if (!writable)
411 		return -EPERM;
412 
413 	if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
414 		return -EFAULT;
415 
416 	memset(&data, 0, sizeof(data));
417 
418 	/* userspace wants to query CSR length */
419 	if (!input.address || !input.length)
420 		goto cmd;
421 
422 	/* allocate a physically contiguous buffer to store the CSR blob */
423 	input_address = (void __user *)input.address;
424 	if (input.length > SEV_FW_BLOB_MAX_SIZE)
425 		return -EFAULT;
426 
427 	blob = kmalloc(input.length, GFP_KERNEL);
428 	if (!blob)
429 		return -ENOMEM;
430 
431 	data.address = __psp_pa(blob);
432 	data.len = input.length;
433 
434 cmd:
435 	if (sev->state == SEV_STATE_UNINIT) {
436 		ret = __sev_platform_init_locked(&argp->error);
437 		if (ret)
438 			goto e_free_blob;
439 	}
440 
441 	ret = __sev_do_cmd_locked(SEV_CMD_PEK_CSR, &data, &argp->error);
442 
443 	 /* If we query the CSR length, FW responded with expected data. */
444 	input.length = data.len;
445 
446 	if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) {
447 		ret = -EFAULT;
448 		goto e_free_blob;
449 	}
450 
451 	if (blob) {
452 		if (copy_to_user(input_address, blob, input.length))
453 			ret = -EFAULT;
454 	}
455 
456 e_free_blob:
457 	kfree(blob);
458 	return ret;
459 }
460 
461 void *psp_copy_user_blob(u64 uaddr, u32 len)
462 {
463 	if (!uaddr || !len)
464 		return ERR_PTR(-EINVAL);
465 
466 	/* verify that blob length does not exceed our limit */
467 	if (len > SEV_FW_BLOB_MAX_SIZE)
468 		return ERR_PTR(-EINVAL);
469 
470 	return memdup_user((void __user *)uaddr, len);
471 }
472 EXPORT_SYMBOL_GPL(psp_copy_user_blob);
473 
474 static int sev_get_api_version(void)
475 {
476 	struct sev_device *sev = psp_master->sev_data;
477 	struct sev_user_data_status status;
478 	int error = 0, ret;
479 
480 	ret = sev_platform_status(&status, &error);
481 	if (ret) {
482 		dev_err(sev->dev,
483 			"SEV: failed to get status. Error: %#x\n", error);
484 		return 1;
485 	}
486 
487 	sev->api_major = status.api_major;
488 	sev->api_minor = status.api_minor;
489 	sev->build = status.build;
490 	sev->state = status.state;
491 
492 	return 0;
493 }
494 
495 static int sev_get_firmware(struct device *dev,
496 			    const struct firmware **firmware)
497 {
498 	char fw_name_specific[SEV_FW_NAME_SIZE];
499 	char fw_name_subset[SEV_FW_NAME_SIZE];
500 
501 	snprintf(fw_name_specific, sizeof(fw_name_specific),
502 		 "amd/amd_sev_fam%.2xh_model%.2xh.sbin",
503 		 boot_cpu_data.x86, boot_cpu_data.x86_model);
504 
505 	snprintf(fw_name_subset, sizeof(fw_name_subset),
506 		 "amd/amd_sev_fam%.2xh_model%.1xxh.sbin",
507 		 boot_cpu_data.x86, (boot_cpu_data.x86_model & 0xf0) >> 4);
508 
509 	/* Check for SEV FW for a particular model.
510 	 * Ex. amd_sev_fam17h_model00h.sbin for Family 17h Model 00h
511 	 *
512 	 * or
513 	 *
514 	 * Check for SEV FW common to a subset of models.
515 	 * Ex. amd_sev_fam17h_model0xh.sbin for
516 	 *     Family 17h Model 00h -- Family 17h Model 0Fh
517 	 *
518 	 * or
519 	 *
520 	 * Fall-back to using generic name: sev.fw
521 	 */
522 	if ((firmware_request_nowarn(firmware, fw_name_specific, dev) >= 0) ||
523 	    (firmware_request_nowarn(firmware, fw_name_subset, dev) >= 0) ||
524 	    (firmware_request_nowarn(firmware, SEV_FW_FILE, dev) >= 0))
525 		return 0;
526 
527 	return -ENOENT;
528 }
529 
530 /* Don't fail if SEV FW couldn't be updated. Continue with existing SEV FW */
531 static int sev_update_firmware(struct device *dev)
532 {
533 	struct sev_data_download_firmware *data;
534 	const struct firmware *firmware;
535 	int ret, error, order;
536 	struct page *p;
537 	u64 data_size;
538 
539 	if (sev_get_firmware(dev, &firmware) == -ENOENT) {
540 		dev_dbg(dev, "No SEV firmware file present\n");
541 		return -1;
542 	}
543 
544 	/*
545 	 * SEV FW expects the physical address given to it to be 32
546 	 * byte aligned. Memory allocated has structure placed at the
547 	 * beginning followed by the firmware being passed to the SEV
548 	 * FW. Allocate enough memory for data structure + alignment
549 	 * padding + SEV FW.
550 	 */
551 	data_size = ALIGN(sizeof(struct sev_data_download_firmware), 32);
552 
553 	order = get_order(firmware->size + data_size);
554 	p = alloc_pages(GFP_KERNEL, order);
555 	if (!p) {
556 		ret = -1;
557 		goto fw_err;
558 	}
559 
560 	/*
561 	 * Copy firmware data to a kernel allocated contiguous
562 	 * memory region.
563 	 */
564 	data = page_address(p);
565 	memcpy(page_address(p) + data_size, firmware->data, firmware->size);
566 
567 	data->address = __psp_pa(page_address(p) + data_size);
568 	data->len = firmware->size;
569 
570 	ret = sev_do_cmd(SEV_CMD_DOWNLOAD_FIRMWARE, data, &error);
571 	if (ret)
572 		dev_dbg(dev, "Failed to update SEV firmware: %#x\n", error);
573 	else
574 		dev_info(dev, "SEV firmware update successful\n");
575 
576 	__free_pages(p, order);
577 
578 fw_err:
579 	release_firmware(firmware);
580 
581 	return ret;
582 }
583 
584 static int sev_ioctl_do_pek_import(struct sev_issue_cmd *argp, bool writable)
585 {
586 	struct sev_device *sev = psp_master->sev_data;
587 	struct sev_user_data_pek_cert_import input;
588 	struct sev_data_pek_cert_import data;
589 	void *pek_blob, *oca_blob;
590 	int ret;
591 
592 	if (!writable)
593 		return -EPERM;
594 
595 	if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
596 		return -EFAULT;
597 
598 	/* copy PEK certificate blobs from userspace */
599 	pek_blob = psp_copy_user_blob(input.pek_cert_address, input.pek_cert_len);
600 	if (IS_ERR(pek_blob))
601 		return PTR_ERR(pek_blob);
602 
603 	data.reserved = 0;
604 	data.pek_cert_address = __psp_pa(pek_blob);
605 	data.pek_cert_len = input.pek_cert_len;
606 
607 	/* copy PEK certificate blobs from userspace */
608 	oca_blob = psp_copy_user_blob(input.oca_cert_address, input.oca_cert_len);
609 	if (IS_ERR(oca_blob)) {
610 		ret = PTR_ERR(oca_blob);
611 		goto e_free_pek;
612 	}
613 
614 	data.oca_cert_address = __psp_pa(oca_blob);
615 	data.oca_cert_len = input.oca_cert_len;
616 
617 	/* If platform is not in INIT state then transition it to INIT */
618 	if (sev->state != SEV_STATE_INIT) {
619 		ret = __sev_platform_init_locked(&argp->error);
620 		if (ret)
621 			goto e_free_oca;
622 	}
623 
624 	ret = __sev_do_cmd_locked(SEV_CMD_PEK_CERT_IMPORT, &data, &argp->error);
625 
626 e_free_oca:
627 	kfree(oca_blob);
628 e_free_pek:
629 	kfree(pek_blob);
630 	return ret;
631 }
632 
633 static int sev_ioctl_do_get_id2(struct sev_issue_cmd *argp)
634 {
635 	struct sev_user_data_get_id2 input;
636 	struct sev_data_get_id data;
637 	void __user *input_address;
638 	void *id_blob = NULL;
639 	int ret;
640 
641 	/* SEV GET_ID is available from SEV API v0.16 and up */
642 	if (!sev_version_greater_or_equal(0, 16))
643 		return -ENOTSUPP;
644 
645 	if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
646 		return -EFAULT;
647 
648 	input_address = (void __user *)input.address;
649 
650 	if (input.address && input.length) {
651 		id_blob = kmalloc(input.length, GFP_KERNEL);
652 		if (!id_blob)
653 			return -ENOMEM;
654 
655 		data.address = __psp_pa(id_blob);
656 		data.len = input.length;
657 	} else {
658 		data.address = 0;
659 		data.len = 0;
660 	}
661 
662 	ret = __sev_do_cmd_locked(SEV_CMD_GET_ID, &data, &argp->error);
663 
664 	/*
665 	 * Firmware will return the length of the ID value (either the minimum
666 	 * required length or the actual length written), return it to the user.
667 	 */
668 	input.length = data.len;
669 
670 	if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) {
671 		ret = -EFAULT;
672 		goto e_free;
673 	}
674 
675 	if (id_blob) {
676 		if (copy_to_user(input_address, id_blob, data.len)) {
677 			ret = -EFAULT;
678 			goto e_free;
679 		}
680 	}
681 
682 e_free:
683 	kfree(id_blob);
684 
685 	return ret;
686 }
687 
688 static int sev_ioctl_do_get_id(struct sev_issue_cmd *argp)
689 {
690 	struct sev_data_get_id *data;
691 	u64 data_size, user_size;
692 	void *id_blob, *mem;
693 	int ret;
694 
695 	/* SEV GET_ID available from SEV API v0.16 and up */
696 	if (!sev_version_greater_or_equal(0, 16))
697 		return -ENOTSUPP;
698 
699 	/* SEV FW expects the buffer it fills with the ID to be
700 	 * 8-byte aligned. Memory allocated should be enough to
701 	 * hold data structure + alignment padding + memory
702 	 * where SEV FW writes the ID.
703 	 */
704 	data_size = ALIGN(sizeof(struct sev_data_get_id), 8);
705 	user_size = sizeof(struct sev_user_data_get_id);
706 
707 	mem = kzalloc(data_size + user_size, GFP_KERNEL);
708 	if (!mem)
709 		return -ENOMEM;
710 
711 	data = mem;
712 	id_blob = mem + data_size;
713 
714 	data->address = __psp_pa(id_blob);
715 	data->len = user_size;
716 
717 	ret = __sev_do_cmd_locked(SEV_CMD_GET_ID, data, &argp->error);
718 	if (!ret) {
719 		if (copy_to_user((void __user *)argp->data, id_blob, data->len))
720 			ret = -EFAULT;
721 	}
722 
723 	kfree(mem);
724 
725 	return ret;
726 }
727 
728 static int sev_ioctl_do_pdh_export(struct sev_issue_cmd *argp, bool writable)
729 {
730 	struct sev_device *sev = psp_master->sev_data;
731 	struct sev_user_data_pdh_cert_export input;
732 	void *pdh_blob = NULL, *cert_blob = NULL;
733 	struct sev_data_pdh_cert_export data;
734 	void __user *input_cert_chain_address;
735 	void __user *input_pdh_cert_address;
736 	int ret;
737 
738 	/* If platform is not in INIT state then transition it to INIT. */
739 	if (sev->state != SEV_STATE_INIT) {
740 		if (!writable)
741 			return -EPERM;
742 
743 		ret = __sev_platform_init_locked(&argp->error);
744 		if (ret)
745 			return ret;
746 	}
747 
748 	if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
749 		return -EFAULT;
750 
751 	memset(&data, 0, sizeof(data));
752 
753 	/* Userspace wants to query the certificate length. */
754 	if (!input.pdh_cert_address ||
755 	    !input.pdh_cert_len ||
756 	    !input.cert_chain_address)
757 		goto cmd;
758 
759 	input_pdh_cert_address = (void __user *)input.pdh_cert_address;
760 	input_cert_chain_address = (void __user *)input.cert_chain_address;
761 
762 	/* Allocate a physically contiguous buffer to store the PDH blob. */
763 	if (input.pdh_cert_len > SEV_FW_BLOB_MAX_SIZE)
764 		return -EFAULT;
765 
766 	/* Allocate a physically contiguous buffer to store the cert chain blob. */
767 	if (input.cert_chain_len > SEV_FW_BLOB_MAX_SIZE)
768 		return -EFAULT;
769 
770 	pdh_blob = kmalloc(input.pdh_cert_len, GFP_KERNEL);
771 	if (!pdh_blob)
772 		return -ENOMEM;
773 
774 	data.pdh_cert_address = __psp_pa(pdh_blob);
775 	data.pdh_cert_len = input.pdh_cert_len;
776 
777 	cert_blob = kmalloc(input.cert_chain_len, GFP_KERNEL);
778 	if (!cert_blob) {
779 		ret = -ENOMEM;
780 		goto e_free_pdh;
781 	}
782 
783 	data.cert_chain_address = __psp_pa(cert_blob);
784 	data.cert_chain_len = input.cert_chain_len;
785 
786 cmd:
787 	ret = __sev_do_cmd_locked(SEV_CMD_PDH_CERT_EXPORT, &data, &argp->error);
788 
789 	/* If we query the length, FW responded with expected data. */
790 	input.cert_chain_len = data.cert_chain_len;
791 	input.pdh_cert_len = data.pdh_cert_len;
792 
793 	if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) {
794 		ret = -EFAULT;
795 		goto e_free_cert;
796 	}
797 
798 	if (pdh_blob) {
799 		if (copy_to_user(input_pdh_cert_address,
800 				 pdh_blob, input.pdh_cert_len)) {
801 			ret = -EFAULT;
802 			goto e_free_cert;
803 		}
804 	}
805 
806 	if (cert_blob) {
807 		if (copy_to_user(input_cert_chain_address,
808 				 cert_blob, input.cert_chain_len))
809 			ret = -EFAULT;
810 	}
811 
812 e_free_cert:
813 	kfree(cert_blob);
814 e_free_pdh:
815 	kfree(pdh_blob);
816 	return ret;
817 }
818 
819 static long sev_ioctl(struct file *file, unsigned int ioctl, unsigned long arg)
820 {
821 	void __user *argp = (void __user *)arg;
822 	struct sev_issue_cmd input;
823 	int ret = -EFAULT;
824 	bool writable = file->f_mode & FMODE_WRITE;
825 
826 	if (!psp_master || !psp_master->sev_data)
827 		return -ENODEV;
828 
829 	if (ioctl != SEV_ISSUE_CMD)
830 		return -EINVAL;
831 
832 	if (copy_from_user(&input, argp, sizeof(struct sev_issue_cmd)))
833 		return -EFAULT;
834 
835 	if (input.cmd > SEV_MAX)
836 		return -EINVAL;
837 
838 	mutex_lock(&sev_cmd_mutex);
839 
840 	switch (input.cmd) {
841 
842 	case SEV_FACTORY_RESET:
843 		ret = sev_ioctl_do_reset(&input, writable);
844 		break;
845 	case SEV_PLATFORM_STATUS:
846 		ret = sev_ioctl_do_platform_status(&input);
847 		break;
848 	case SEV_PEK_GEN:
849 		ret = sev_ioctl_do_pek_pdh_gen(SEV_CMD_PEK_GEN, &input, writable);
850 		break;
851 	case SEV_PDH_GEN:
852 		ret = sev_ioctl_do_pek_pdh_gen(SEV_CMD_PDH_GEN, &input, writable);
853 		break;
854 	case SEV_PEK_CSR:
855 		ret = sev_ioctl_do_pek_csr(&input, writable);
856 		break;
857 	case SEV_PEK_CERT_IMPORT:
858 		ret = sev_ioctl_do_pek_import(&input, writable);
859 		break;
860 	case SEV_PDH_CERT_EXPORT:
861 		ret = sev_ioctl_do_pdh_export(&input, writable);
862 		break;
863 	case SEV_GET_ID:
864 		pr_warn_once("SEV_GET_ID command is deprecated, use SEV_GET_ID2\n");
865 		ret = sev_ioctl_do_get_id(&input);
866 		break;
867 	case SEV_GET_ID2:
868 		ret = sev_ioctl_do_get_id2(&input);
869 		break;
870 	default:
871 		ret = -EINVAL;
872 		goto out;
873 	}
874 
875 	if (copy_to_user(argp, &input, sizeof(struct sev_issue_cmd)))
876 		ret = -EFAULT;
877 out:
878 	mutex_unlock(&sev_cmd_mutex);
879 
880 	return ret;
881 }
882 
883 static const struct file_operations sev_fops = {
884 	.owner	= THIS_MODULE,
885 	.unlocked_ioctl = sev_ioctl,
886 };
887 
888 int sev_platform_status(struct sev_user_data_status *data, int *error)
889 {
890 	return sev_do_cmd(SEV_CMD_PLATFORM_STATUS, data, error);
891 }
892 EXPORT_SYMBOL_GPL(sev_platform_status);
893 
894 int sev_guest_deactivate(struct sev_data_deactivate *data, int *error)
895 {
896 	return sev_do_cmd(SEV_CMD_DEACTIVATE, data, error);
897 }
898 EXPORT_SYMBOL_GPL(sev_guest_deactivate);
899 
900 int sev_guest_activate(struct sev_data_activate *data, int *error)
901 {
902 	return sev_do_cmd(SEV_CMD_ACTIVATE, data, error);
903 }
904 EXPORT_SYMBOL_GPL(sev_guest_activate);
905 
906 int sev_guest_decommission(struct sev_data_decommission *data, int *error)
907 {
908 	return sev_do_cmd(SEV_CMD_DECOMMISSION, data, error);
909 }
910 EXPORT_SYMBOL_GPL(sev_guest_decommission);
911 
912 int sev_guest_df_flush(int *error)
913 {
914 	return sev_do_cmd(SEV_CMD_DF_FLUSH, NULL, error);
915 }
916 EXPORT_SYMBOL_GPL(sev_guest_df_flush);
917 
918 static void sev_exit(struct kref *ref)
919 {
920 	misc_deregister(&misc_dev->misc);
921 	kfree(misc_dev);
922 	misc_dev = NULL;
923 }
924 
925 static int sev_misc_init(struct sev_device *sev)
926 {
927 	struct device *dev = sev->dev;
928 	int ret;
929 
930 	/*
931 	 * SEV feature support can be detected on multiple devices but the SEV
932 	 * FW commands must be issued on the master. During probe, we do not
933 	 * know the master hence we create /dev/sev on the first device probe.
934 	 * sev_do_cmd() finds the right master device to which to issue the
935 	 * command to the firmware.
936 	 */
937 	if (!misc_dev) {
938 		struct miscdevice *misc;
939 
940 		misc_dev = kzalloc(sizeof(*misc_dev), GFP_KERNEL);
941 		if (!misc_dev)
942 			return -ENOMEM;
943 
944 		misc = &misc_dev->misc;
945 		misc->minor = MISC_DYNAMIC_MINOR;
946 		misc->name = DEVICE_NAME;
947 		misc->fops = &sev_fops;
948 
949 		ret = misc_register(misc);
950 		if (ret)
951 			return ret;
952 
953 		kref_init(&misc_dev->refcount);
954 	} else {
955 		kref_get(&misc_dev->refcount);
956 	}
957 
958 	init_waitqueue_head(&sev->int_queue);
959 	sev->misc = misc_dev;
960 	dev_dbg(dev, "registered SEV device\n");
961 
962 	return 0;
963 }
964 
965 int sev_dev_init(struct psp_device *psp)
966 {
967 	struct device *dev = psp->dev;
968 	struct sev_device *sev;
969 	int ret = -ENOMEM;
970 
971 	if (!boot_cpu_has(X86_FEATURE_SEV)) {
972 		dev_info_once(dev, "SEV: memory encryption not enabled by BIOS\n");
973 		return 0;
974 	}
975 
976 	sev = devm_kzalloc(dev, sizeof(*sev), GFP_KERNEL);
977 	if (!sev)
978 		goto e_err;
979 
980 	sev->cmd_buf = (void *)devm_get_free_pages(dev, GFP_KERNEL, 0);
981 	if (!sev->cmd_buf)
982 		goto e_sev;
983 
984 	psp->sev_data = sev;
985 
986 	sev->dev = dev;
987 	sev->psp = psp;
988 
989 	sev->io_regs = psp->io_regs;
990 
991 	sev->vdata = (struct sev_vdata *)psp->vdata->sev;
992 	if (!sev->vdata) {
993 		ret = -ENODEV;
994 		dev_err(dev, "sev: missing driver data\n");
995 		goto e_buf;
996 	}
997 
998 	psp_set_sev_irq_handler(psp, sev_irq_handler, sev);
999 
1000 	ret = sev_misc_init(sev);
1001 	if (ret)
1002 		goto e_irq;
1003 
1004 	dev_notice(dev, "sev enabled\n");
1005 
1006 	return 0;
1007 
1008 e_irq:
1009 	psp_clear_sev_irq_handler(psp);
1010 e_buf:
1011 	devm_free_pages(dev, (unsigned long)sev->cmd_buf);
1012 e_sev:
1013 	devm_kfree(dev, sev);
1014 e_err:
1015 	psp->sev_data = NULL;
1016 
1017 	dev_notice(dev, "sev initialization failed\n");
1018 
1019 	return ret;
1020 }
1021 
1022 void sev_dev_destroy(struct psp_device *psp)
1023 {
1024 	struct sev_device *sev = psp->sev_data;
1025 
1026 	if (!sev)
1027 		return;
1028 
1029 	if (sev->misc)
1030 		kref_put(&misc_dev->refcount, sev_exit);
1031 
1032 	psp_clear_sev_irq_handler(psp);
1033 }
1034 
1035 int sev_issue_cmd_external_user(struct file *filep, unsigned int cmd,
1036 				void *data, int *error)
1037 {
1038 	if (!filep || filep->f_op != &sev_fops)
1039 		return -EBADF;
1040 
1041 	return sev_do_cmd(cmd, data, error);
1042 }
1043 EXPORT_SYMBOL_GPL(sev_issue_cmd_external_user);
1044 
1045 void sev_pci_init(void)
1046 {
1047 	struct sev_device *sev = psp_master->sev_data;
1048 	struct page *tmr_page;
1049 	int error, rc;
1050 
1051 	if (!sev)
1052 		return;
1053 
1054 	psp_timeout = psp_probe_timeout;
1055 
1056 	if (sev_get_api_version())
1057 		goto err;
1058 
1059 	/*
1060 	 * If platform is not in UNINIT state then firmware upgrade and/or
1061 	 * platform INIT command will fail. These command require UNINIT state.
1062 	 *
1063 	 * In a normal boot we should never run into case where the firmware
1064 	 * is not in UNINIT state on boot. But in case of kexec boot, a reboot
1065 	 * may not go through a typical shutdown sequence and may leave the
1066 	 * firmware in INIT or WORKING state.
1067 	 */
1068 
1069 	if (sev->state != SEV_STATE_UNINIT) {
1070 		sev_platform_shutdown(NULL);
1071 		sev->state = SEV_STATE_UNINIT;
1072 	}
1073 
1074 	if (sev_version_greater_or_equal(0, 15) &&
1075 	    sev_update_firmware(sev->dev) == 0)
1076 		sev_get_api_version();
1077 
1078 	/* Obtain the TMR memory area for SEV-ES use */
1079 	tmr_page = alloc_pages(GFP_KERNEL, get_order(SEV_ES_TMR_SIZE));
1080 	if (tmr_page) {
1081 		sev_es_tmr = page_address(tmr_page);
1082 	} else {
1083 		sev_es_tmr = NULL;
1084 		dev_warn(sev->dev,
1085 			 "SEV: TMR allocation failed, SEV-ES support unavailable\n");
1086 	}
1087 
1088 	/* Initialize the platform */
1089 	rc = sev_platform_init(&error);
1090 	if (rc && (error == SEV_RET_SECURE_DATA_INVALID)) {
1091 		/*
1092 		 * INIT command returned an integrity check failure
1093 		 * status code, meaning that firmware load and
1094 		 * validation of SEV related persistent data has
1095 		 * failed and persistent state has been erased.
1096 		 * Retrying INIT command here should succeed.
1097 		 */
1098 		dev_dbg(sev->dev, "SEV: retrying INIT command");
1099 		rc = sev_platform_init(&error);
1100 	}
1101 
1102 	if (rc) {
1103 		dev_err(sev->dev, "SEV: failed to INIT error %#x\n", error);
1104 		return;
1105 	}
1106 
1107 	dev_info(sev->dev, "SEV API:%d.%d build:%d\n", sev->api_major,
1108 		 sev->api_minor, sev->build);
1109 
1110 	return;
1111 
1112 err:
1113 	psp_master->sev_data = NULL;
1114 }
1115 
1116 void sev_pci_exit(void)
1117 {
1118 	if (!psp_master->sev_data)
1119 		return;
1120 
1121 	sev_platform_shutdown(NULL);
1122 
1123 	if (sev_es_tmr) {
1124 		/* The TMR area was encrypted, flush it from the cache */
1125 		wbinvd_on_all_cpus();
1126 
1127 		free_pages((unsigned long)sev_es_tmr,
1128 			   get_order(SEV_ES_TMR_SIZE));
1129 		sev_es_tmr = NULL;
1130 	}
1131 }
1132