xref: /linux/drivers/crypto/ccp/sev-dev.c (revision 9c39c6ffe0c2945c7cf814814c096bc23b63f53d)
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 static bool psp_dead;
47 static int psp_timeout;
48 
49 /* Trusted Memory Region (TMR):
50  *   The TMR is a 1MB area that must be 1MB aligned.  Use the page allocator
51  *   to allocate the memory, which will return aligned memory for the specified
52  *   allocation order.
53  */
54 #define SEV_ES_TMR_SIZE		(1024 * 1024)
55 static void *sev_es_tmr;
56 
57 static inline bool sev_version_greater_or_equal(u8 maj, u8 min)
58 {
59 	struct sev_device *sev = psp_master->sev_data;
60 
61 	if (sev->api_major > maj)
62 		return true;
63 
64 	if (sev->api_major == maj && sev->api_minor >= min)
65 		return true;
66 
67 	return false;
68 }
69 
70 static void sev_irq_handler(int irq, void *data, unsigned int status)
71 {
72 	struct sev_device *sev = data;
73 	int reg;
74 
75 	/* Check if it is command completion: */
76 	if (!(status & SEV_CMD_COMPLETE))
77 		return;
78 
79 	/* Check if it is SEV command completion: */
80 	reg = ioread32(sev->io_regs + sev->vdata->cmdresp_reg);
81 	if (reg & PSP_CMDRESP_RESP) {
82 		sev->int_rcvd = 1;
83 		wake_up(&sev->int_queue);
84 	}
85 }
86 
87 static int sev_wait_cmd_ioc(struct sev_device *sev,
88 			    unsigned int *reg, unsigned int timeout)
89 {
90 	int ret;
91 
92 	ret = wait_event_timeout(sev->int_queue,
93 			sev->int_rcvd, timeout * HZ);
94 	if (!ret)
95 		return -ETIMEDOUT;
96 
97 	*reg = ioread32(sev->io_regs + sev->vdata->cmdresp_reg);
98 
99 	return 0;
100 }
101 
102 static int sev_cmd_buffer_len(int cmd)
103 {
104 	switch (cmd) {
105 	case SEV_CMD_INIT:			return sizeof(struct sev_data_init);
106 	case SEV_CMD_PLATFORM_STATUS:		return sizeof(struct sev_user_data_status);
107 	case SEV_CMD_PEK_CSR:			return sizeof(struct sev_data_pek_csr);
108 	case SEV_CMD_PEK_CERT_IMPORT:		return sizeof(struct sev_data_pek_cert_import);
109 	case SEV_CMD_PDH_CERT_EXPORT:		return sizeof(struct sev_data_pdh_cert_export);
110 	case SEV_CMD_LAUNCH_START:		return sizeof(struct sev_data_launch_start);
111 	case SEV_CMD_LAUNCH_UPDATE_DATA:	return sizeof(struct sev_data_launch_update_data);
112 	case SEV_CMD_LAUNCH_UPDATE_VMSA:	return sizeof(struct sev_data_launch_update_vmsa);
113 	case SEV_CMD_LAUNCH_FINISH:		return sizeof(struct sev_data_launch_finish);
114 	case SEV_CMD_LAUNCH_MEASURE:		return sizeof(struct sev_data_launch_measure);
115 	case SEV_CMD_ACTIVATE:			return sizeof(struct sev_data_activate);
116 	case SEV_CMD_DEACTIVATE:		return sizeof(struct sev_data_deactivate);
117 	case SEV_CMD_DECOMMISSION:		return sizeof(struct sev_data_decommission);
118 	case SEV_CMD_GUEST_STATUS:		return sizeof(struct sev_data_guest_status);
119 	case SEV_CMD_DBG_DECRYPT:		return sizeof(struct sev_data_dbg);
120 	case SEV_CMD_DBG_ENCRYPT:		return sizeof(struct sev_data_dbg);
121 	case SEV_CMD_SEND_START:		return sizeof(struct sev_data_send_start);
122 	case SEV_CMD_SEND_UPDATE_DATA:		return sizeof(struct sev_data_send_update_data);
123 	case SEV_CMD_SEND_UPDATE_VMSA:		return sizeof(struct sev_data_send_update_vmsa);
124 	case SEV_CMD_SEND_FINISH:		return sizeof(struct sev_data_send_finish);
125 	case SEV_CMD_RECEIVE_START:		return sizeof(struct sev_data_receive_start);
126 	case SEV_CMD_RECEIVE_FINISH:		return sizeof(struct sev_data_receive_finish);
127 	case SEV_CMD_RECEIVE_UPDATE_DATA:	return sizeof(struct sev_data_receive_update_data);
128 	case SEV_CMD_RECEIVE_UPDATE_VMSA:	return sizeof(struct sev_data_receive_update_vmsa);
129 	case SEV_CMD_LAUNCH_UPDATE_SECRET:	return sizeof(struct sev_data_launch_secret);
130 	case SEV_CMD_DOWNLOAD_FIRMWARE:		return sizeof(struct sev_data_download_firmware);
131 	case SEV_CMD_GET_ID:			return sizeof(struct sev_data_get_id);
132 	case SEV_CMD_ATTESTATION_REPORT:	return sizeof(struct sev_data_attestation_report);
133 	default:				return 0;
134 	}
135 
136 	return 0;
137 }
138 
139 static int __sev_do_cmd_locked(int cmd, void *data, int *psp_ret)
140 {
141 	struct psp_device *psp = psp_master;
142 	struct sev_device *sev;
143 	unsigned int phys_lsb, phys_msb;
144 	unsigned int reg, ret = 0;
145 
146 	if (!psp || !psp->sev_data)
147 		return -ENODEV;
148 
149 	if (psp_dead)
150 		return -EBUSY;
151 
152 	sev = psp->sev_data;
153 
154 	/* Get the physical address of the command buffer */
155 	phys_lsb = data ? lower_32_bits(__psp_pa(data)) : 0;
156 	phys_msb = data ? upper_32_bits(__psp_pa(data)) : 0;
157 
158 	dev_dbg(sev->dev, "sev command id %#x buffer 0x%08x%08x timeout %us\n",
159 		cmd, phys_msb, phys_lsb, psp_timeout);
160 
161 	print_hex_dump_debug("(in):  ", DUMP_PREFIX_OFFSET, 16, 2, data,
162 			     sev_cmd_buffer_len(cmd), false);
163 
164 	iowrite32(phys_lsb, sev->io_regs + sev->vdata->cmdbuff_addr_lo_reg);
165 	iowrite32(phys_msb, sev->io_regs + sev->vdata->cmdbuff_addr_hi_reg);
166 
167 	sev->int_rcvd = 0;
168 
169 	reg = cmd;
170 	reg <<= SEV_CMDRESP_CMD_SHIFT;
171 	reg |= SEV_CMDRESP_IOC;
172 	iowrite32(reg, sev->io_regs + sev->vdata->cmdresp_reg);
173 
174 	/* wait for command completion */
175 	ret = sev_wait_cmd_ioc(sev, &reg, psp_timeout);
176 	if (ret) {
177 		if (psp_ret)
178 			*psp_ret = 0;
179 
180 		dev_err(sev->dev, "sev command %#x timed out, disabling PSP\n", cmd);
181 		psp_dead = true;
182 
183 		return ret;
184 	}
185 
186 	psp_timeout = psp_cmd_timeout;
187 
188 	if (psp_ret)
189 		*psp_ret = reg & PSP_CMDRESP_ERR_MASK;
190 
191 	if (reg & PSP_CMDRESP_ERR_MASK) {
192 		dev_dbg(sev->dev, "sev command %#x failed (%#010x)\n",
193 			cmd, reg & PSP_CMDRESP_ERR_MASK);
194 		ret = -EIO;
195 	}
196 
197 	print_hex_dump_debug("(out): ", DUMP_PREFIX_OFFSET, 16, 2, data,
198 			     sev_cmd_buffer_len(cmd), false);
199 
200 	return ret;
201 }
202 
203 static int sev_do_cmd(int cmd, void *data, int *psp_ret)
204 {
205 	int rc;
206 
207 	mutex_lock(&sev_cmd_mutex);
208 	rc = __sev_do_cmd_locked(cmd, data, psp_ret);
209 	mutex_unlock(&sev_cmd_mutex);
210 
211 	return rc;
212 }
213 
214 static int __sev_platform_init_locked(int *error)
215 {
216 	struct psp_device *psp = psp_master;
217 	struct sev_device *sev;
218 	int rc = 0;
219 
220 	if (!psp || !psp->sev_data)
221 		return -ENODEV;
222 
223 	sev = psp->sev_data;
224 
225 	if (sev->state == SEV_STATE_INIT)
226 		return 0;
227 
228 	if (sev_es_tmr) {
229 		u64 tmr_pa;
230 
231 		/*
232 		 * Do not include the encryption mask on the physical
233 		 * address of the TMR (firmware should clear it anyway).
234 		 */
235 		tmr_pa = __pa(sev_es_tmr);
236 
237 		sev->init_cmd_buf.flags |= SEV_INIT_FLAGS_SEV_ES;
238 		sev->init_cmd_buf.tmr_address = tmr_pa;
239 		sev->init_cmd_buf.tmr_len = SEV_ES_TMR_SIZE;
240 	}
241 
242 	rc = __sev_do_cmd_locked(SEV_CMD_INIT, &sev->init_cmd_buf, error);
243 	if (rc)
244 		return rc;
245 
246 	sev->state = SEV_STATE_INIT;
247 
248 	/* Prepare for first SEV guest launch after INIT */
249 	wbinvd_on_all_cpus();
250 	rc = __sev_do_cmd_locked(SEV_CMD_DF_FLUSH, NULL, error);
251 	if (rc)
252 		return rc;
253 
254 	dev_dbg(sev->dev, "SEV firmware initialized\n");
255 
256 	return rc;
257 }
258 
259 int sev_platform_init(int *error)
260 {
261 	int rc;
262 
263 	mutex_lock(&sev_cmd_mutex);
264 	rc = __sev_platform_init_locked(error);
265 	mutex_unlock(&sev_cmd_mutex);
266 
267 	return rc;
268 }
269 EXPORT_SYMBOL_GPL(sev_platform_init);
270 
271 static int __sev_platform_shutdown_locked(int *error)
272 {
273 	struct sev_device *sev = psp_master->sev_data;
274 	int ret;
275 
276 	ret = __sev_do_cmd_locked(SEV_CMD_SHUTDOWN, NULL, error);
277 	if (ret)
278 		return ret;
279 
280 	sev->state = SEV_STATE_UNINIT;
281 	dev_dbg(sev->dev, "SEV firmware shutdown\n");
282 
283 	return ret;
284 }
285 
286 static int sev_platform_shutdown(int *error)
287 {
288 	int rc;
289 
290 	mutex_lock(&sev_cmd_mutex);
291 	rc = __sev_platform_shutdown_locked(NULL);
292 	mutex_unlock(&sev_cmd_mutex);
293 
294 	return rc;
295 }
296 
297 static int sev_get_platform_state(int *state, int *error)
298 {
299 	struct sev_device *sev = psp_master->sev_data;
300 	int rc;
301 
302 	rc = __sev_do_cmd_locked(SEV_CMD_PLATFORM_STATUS,
303 				 &sev->status_cmd_buf, error);
304 	if (rc)
305 		return rc;
306 
307 	*state = sev->status_cmd_buf.state;
308 	return rc;
309 }
310 
311 static int sev_ioctl_do_reset(struct sev_issue_cmd *argp, bool writable)
312 {
313 	int state, rc;
314 
315 	if (!writable)
316 		return -EPERM;
317 
318 	/*
319 	 * The SEV spec requires that FACTORY_RESET must be issued in
320 	 * UNINIT state. Before we go further lets check if any guest is
321 	 * active.
322 	 *
323 	 * If FW is in WORKING state then deny the request otherwise issue
324 	 * SHUTDOWN command do INIT -> UNINIT before issuing the FACTORY_RESET.
325 	 *
326 	 */
327 	rc = sev_get_platform_state(&state, &argp->error);
328 	if (rc)
329 		return rc;
330 
331 	if (state == SEV_STATE_WORKING)
332 		return -EBUSY;
333 
334 	if (state == SEV_STATE_INIT) {
335 		rc = __sev_platform_shutdown_locked(&argp->error);
336 		if (rc)
337 			return rc;
338 	}
339 
340 	return __sev_do_cmd_locked(SEV_CMD_FACTORY_RESET, NULL, &argp->error);
341 }
342 
343 static int sev_ioctl_do_platform_status(struct sev_issue_cmd *argp)
344 {
345 	struct sev_device *sev = psp_master->sev_data;
346 	struct sev_user_data_status *data = &sev->status_cmd_buf;
347 	int ret;
348 
349 	ret = __sev_do_cmd_locked(SEV_CMD_PLATFORM_STATUS, data, &argp->error);
350 	if (ret)
351 		return ret;
352 
353 	if (copy_to_user((void __user *)argp->data, data, sizeof(*data)))
354 		ret = -EFAULT;
355 
356 	return ret;
357 }
358 
359 static int sev_ioctl_do_pek_pdh_gen(int cmd, struct sev_issue_cmd *argp, bool writable)
360 {
361 	struct sev_device *sev = psp_master->sev_data;
362 	int rc;
363 
364 	if (!writable)
365 		return -EPERM;
366 
367 	if (sev->state == SEV_STATE_UNINIT) {
368 		rc = __sev_platform_init_locked(&argp->error);
369 		if (rc)
370 			return rc;
371 	}
372 
373 	return __sev_do_cmd_locked(cmd, NULL, &argp->error);
374 }
375 
376 static int sev_ioctl_do_pek_csr(struct sev_issue_cmd *argp, bool writable)
377 {
378 	struct sev_device *sev = psp_master->sev_data;
379 	struct sev_user_data_pek_csr input;
380 	struct sev_data_pek_csr *data;
381 	void __user *input_address;
382 	void *blob = NULL;
383 	int ret;
384 
385 	if (!writable)
386 		return -EPERM;
387 
388 	if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
389 		return -EFAULT;
390 
391 	data = kzalloc(sizeof(*data), GFP_KERNEL);
392 	if (!data)
393 		return -ENOMEM;
394 
395 	/* userspace wants to query CSR length */
396 	if (!input.address || !input.length)
397 		goto cmd;
398 
399 	/* allocate a physically contiguous buffer to store the CSR blob */
400 	input_address = (void __user *)input.address;
401 	if (input.length > SEV_FW_BLOB_MAX_SIZE) {
402 		ret = -EFAULT;
403 		goto e_free;
404 	}
405 
406 	blob = kmalloc(input.length, GFP_KERNEL);
407 	if (!blob) {
408 		ret = -ENOMEM;
409 		goto e_free;
410 	}
411 
412 	data->address = __psp_pa(blob);
413 	data->len = input.length;
414 
415 cmd:
416 	if (sev->state == SEV_STATE_UNINIT) {
417 		ret = __sev_platform_init_locked(&argp->error);
418 		if (ret)
419 			goto e_free_blob;
420 	}
421 
422 	ret = __sev_do_cmd_locked(SEV_CMD_PEK_CSR, data, &argp->error);
423 
424 	 /* If we query the CSR length, FW responded with expected data. */
425 	input.length = data->len;
426 
427 	if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) {
428 		ret = -EFAULT;
429 		goto e_free_blob;
430 	}
431 
432 	if (blob) {
433 		if (copy_to_user(input_address, blob, input.length))
434 			ret = -EFAULT;
435 	}
436 
437 e_free_blob:
438 	kfree(blob);
439 e_free:
440 	kfree(data);
441 	return ret;
442 }
443 
444 void *psp_copy_user_blob(u64 uaddr, u32 len)
445 {
446 	if (!uaddr || !len)
447 		return ERR_PTR(-EINVAL);
448 
449 	/* verify that blob length does not exceed our limit */
450 	if (len > SEV_FW_BLOB_MAX_SIZE)
451 		return ERR_PTR(-EINVAL);
452 
453 	return memdup_user((void __user *)uaddr, len);
454 }
455 EXPORT_SYMBOL_GPL(psp_copy_user_blob);
456 
457 static int sev_get_api_version(void)
458 {
459 	struct sev_device *sev = psp_master->sev_data;
460 	struct sev_user_data_status *status;
461 	int error = 0, ret;
462 
463 	status = &sev->status_cmd_buf;
464 	ret = sev_platform_status(status, &error);
465 	if (ret) {
466 		dev_err(sev->dev,
467 			"SEV: failed to get status. Error: %#x\n", error);
468 		return 1;
469 	}
470 
471 	sev->api_major = status->api_major;
472 	sev->api_minor = status->api_minor;
473 	sev->build = status->build;
474 	sev->state = status->state;
475 
476 	return 0;
477 }
478 
479 static int sev_get_firmware(struct device *dev,
480 			    const struct firmware **firmware)
481 {
482 	char fw_name_specific[SEV_FW_NAME_SIZE];
483 	char fw_name_subset[SEV_FW_NAME_SIZE];
484 
485 	snprintf(fw_name_specific, sizeof(fw_name_specific),
486 		 "amd/amd_sev_fam%.2xh_model%.2xh.sbin",
487 		 boot_cpu_data.x86, boot_cpu_data.x86_model);
488 
489 	snprintf(fw_name_subset, sizeof(fw_name_subset),
490 		 "amd/amd_sev_fam%.2xh_model%.1xxh.sbin",
491 		 boot_cpu_data.x86, (boot_cpu_data.x86_model & 0xf0) >> 4);
492 
493 	/* Check for SEV FW for a particular model.
494 	 * Ex. amd_sev_fam17h_model00h.sbin for Family 17h Model 00h
495 	 *
496 	 * or
497 	 *
498 	 * Check for SEV FW common to a subset of models.
499 	 * Ex. amd_sev_fam17h_model0xh.sbin for
500 	 *     Family 17h Model 00h -- Family 17h Model 0Fh
501 	 *
502 	 * or
503 	 *
504 	 * Fall-back to using generic name: sev.fw
505 	 */
506 	if ((firmware_request_nowarn(firmware, fw_name_specific, dev) >= 0) ||
507 	    (firmware_request_nowarn(firmware, fw_name_subset, dev) >= 0) ||
508 	    (firmware_request_nowarn(firmware, SEV_FW_FILE, dev) >= 0))
509 		return 0;
510 
511 	return -ENOENT;
512 }
513 
514 /* Don't fail if SEV FW couldn't be updated. Continue with existing SEV FW */
515 static int sev_update_firmware(struct device *dev)
516 {
517 	struct sev_data_download_firmware *data;
518 	const struct firmware *firmware;
519 	int ret, error, order;
520 	struct page *p;
521 	u64 data_size;
522 
523 	if (sev_get_firmware(dev, &firmware) == -ENOENT) {
524 		dev_dbg(dev, "No SEV firmware file present\n");
525 		return -1;
526 	}
527 
528 	/*
529 	 * SEV FW expects the physical address given to it to be 32
530 	 * byte aligned. Memory allocated has structure placed at the
531 	 * beginning followed by the firmware being passed to the SEV
532 	 * FW. Allocate enough memory for data structure + alignment
533 	 * padding + SEV FW.
534 	 */
535 	data_size = ALIGN(sizeof(struct sev_data_download_firmware), 32);
536 
537 	order = get_order(firmware->size + data_size);
538 	p = alloc_pages(GFP_KERNEL, order);
539 	if (!p) {
540 		ret = -1;
541 		goto fw_err;
542 	}
543 
544 	/*
545 	 * Copy firmware data to a kernel allocated contiguous
546 	 * memory region.
547 	 */
548 	data = page_address(p);
549 	memcpy(page_address(p) + data_size, firmware->data, firmware->size);
550 
551 	data->address = __psp_pa(page_address(p) + data_size);
552 	data->len = firmware->size;
553 
554 	ret = sev_do_cmd(SEV_CMD_DOWNLOAD_FIRMWARE, data, &error);
555 	if (ret)
556 		dev_dbg(dev, "Failed to update SEV firmware: %#x\n", error);
557 	else
558 		dev_info(dev, "SEV firmware update successful\n");
559 
560 	__free_pages(p, order);
561 
562 fw_err:
563 	release_firmware(firmware);
564 
565 	return ret;
566 }
567 
568 static int sev_ioctl_do_pek_import(struct sev_issue_cmd *argp, bool writable)
569 {
570 	struct sev_device *sev = psp_master->sev_data;
571 	struct sev_user_data_pek_cert_import input;
572 	struct sev_data_pek_cert_import *data;
573 	void *pek_blob, *oca_blob;
574 	int ret;
575 
576 	if (!writable)
577 		return -EPERM;
578 
579 	if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
580 		return -EFAULT;
581 
582 	data = kzalloc(sizeof(*data), GFP_KERNEL);
583 	if (!data)
584 		return -ENOMEM;
585 
586 	/* copy PEK certificate blobs from userspace */
587 	pek_blob = psp_copy_user_blob(input.pek_cert_address, input.pek_cert_len);
588 	if (IS_ERR(pek_blob)) {
589 		ret = PTR_ERR(pek_blob);
590 		goto e_free;
591 	}
592 
593 	data->pek_cert_address = __psp_pa(pek_blob);
594 	data->pek_cert_len = input.pek_cert_len;
595 
596 	/* copy PEK certificate blobs from userspace */
597 	oca_blob = psp_copy_user_blob(input.oca_cert_address, input.oca_cert_len);
598 	if (IS_ERR(oca_blob)) {
599 		ret = PTR_ERR(oca_blob);
600 		goto e_free_pek;
601 	}
602 
603 	data->oca_cert_address = __psp_pa(oca_blob);
604 	data->oca_cert_len = input.oca_cert_len;
605 
606 	/* If platform is not in INIT state then transition it to INIT */
607 	if (sev->state != SEV_STATE_INIT) {
608 		ret = __sev_platform_init_locked(&argp->error);
609 		if (ret)
610 			goto e_free_oca;
611 	}
612 
613 	ret = __sev_do_cmd_locked(SEV_CMD_PEK_CERT_IMPORT, data, &argp->error);
614 
615 e_free_oca:
616 	kfree(oca_blob);
617 e_free_pek:
618 	kfree(pek_blob);
619 e_free:
620 	kfree(data);
621 	return ret;
622 }
623 
624 static int sev_ioctl_do_get_id2(struct sev_issue_cmd *argp)
625 {
626 	struct sev_user_data_get_id2 input;
627 	struct sev_data_get_id *data;
628 	void __user *input_address;
629 	void *id_blob = NULL;
630 	int ret;
631 
632 	/* SEV GET_ID is available from SEV API v0.16 and up */
633 	if (!sev_version_greater_or_equal(0, 16))
634 		return -ENOTSUPP;
635 
636 	if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
637 		return -EFAULT;
638 
639 	input_address = (void __user *)input.address;
640 
641 	data = kzalloc(sizeof(*data), GFP_KERNEL);
642 	if (!data)
643 		return -ENOMEM;
644 
645 	if (input.address && input.length) {
646 		id_blob = kmalloc(input.length, GFP_KERNEL);
647 		if (!id_blob) {
648 			kfree(data);
649 			return -ENOMEM;
650 		}
651 
652 		data->address = __psp_pa(id_blob);
653 		data->len = input.length;
654 	}
655 
656 	ret = __sev_do_cmd_locked(SEV_CMD_GET_ID, data, &argp->error);
657 
658 	/*
659 	 * Firmware will return the length of the ID value (either the minimum
660 	 * required length or the actual length written), return it to the user.
661 	 */
662 	input.length = data->len;
663 
664 	if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) {
665 		ret = -EFAULT;
666 		goto e_free;
667 	}
668 
669 	if (id_blob) {
670 		if (copy_to_user(input_address, id_blob, data->len)) {
671 			ret = -EFAULT;
672 			goto e_free;
673 		}
674 	}
675 
676 e_free:
677 	kfree(id_blob);
678 	kfree(data);
679 
680 	return ret;
681 }
682 
683 static int sev_ioctl_do_get_id(struct sev_issue_cmd *argp)
684 {
685 	struct sev_data_get_id *data;
686 	u64 data_size, user_size;
687 	void *id_blob, *mem;
688 	int ret;
689 
690 	/* SEV GET_ID available from SEV API v0.16 and up */
691 	if (!sev_version_greater_or_equal(0, 16))
692 		return -ENOTSUPP;
693 
694 	/* SEV FW expects the buffer it fills with the ID to be
695 	 * 8-byte aligned. Memory allocated should be enough to
696 	 * hold data structure + alignment padding + memory
697 	 * where SEV FW writes the ID.
698 	 */
699 	data_size = ALIGN(sizeof(struct sev_data_get_id), 8);
700 	user_size = sizeof(struct sev_user_data_get_id);
701 
702 	mem = kzalloc(data_size + user_size, GFP_KERNEL);
703 	if (!mem)
704 		return -ENOMEM;
705 
706 	data = mem;
707 	id_blob = mem + data_size;
708 
709 	data->address = __psp_pa(id_blob);
710 	data->len = user_size;
711 
712 	ret = __sev_do_cmd_locked(SEV_CMD_GET_ID, data, &argp->error);
713 	if (!ret) {
714 		if (copy_to_user((void __user *)argp->data, id_blob, data->len))
715 			ret = -EFAULT;
716 	}
717 
718 	kfree(mem);
719 
720 	return ret;
721 }
722 
723 static int sev_ioctl_do_pdh_export(struct sev_issue_cmd *argp, bool writable)
724 {
725 	struct sev_device *sev = psp_master->sev_data;
726 	struct sev_user_data_pdh_cert_export input;
727 	void *pdh_blob = NULL, *cert_blob = NULL;
728 	struct sev_data_pdh_cert_export *data;
729 	void __user *input_cert_chain_address;
730 	void __user *input_pdh_cert_address;
731 	int ret;
732 
733 	/* If platform is not in INIT state then transition it to INIT. */
734 	if (sev->state != SEV_STATE_INIT) {
735 		if (!writable)
736 			return -EPERM;
737 
738 		ret = __sev_platform_init_locked(&argp->error);
739 		if (ret)
740 			return ret;
741 	}
742 
743 	if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
744 		return -EFAULT;
745 
746 	data = kzalloc(sizeof(*data), GFP_KERNEL);
747 	if (!data)
748 		return -ENOMEM;
749 
750 	/* Userspace wants to query the certificate length. */
751 	if (!input.pdh_cert_address ||
752 	    !input.pdh_cert_len ||
753 	    !input.cert_chain_address)
754 		goto cmd;
755 
756 	input_pdh_cert_address = (void __user *)input.pdh_cert_address;
757 	input_cert_chain_address = (void __user *)input.cert_chain_address;
758 
759 	/* Allocate a physically contiguous buffer to store the PDH blob. */
760 	if (input.pdh_cert_len > SEV_FW_BLOB_MAX_SIZE) {
761 		ret = -EFAULT;
762 		goto e_free;
763 	}
764 
765 	/* Allocate a physically contiguous buffer to store the cert chain blob. */
766 	if (input.cert_chain_len > SEV_FW_BLOB_MAX_SIZE) {
767 		ret = -EFAULT;
768 		goto e_free;
769 	}
770 
771 	pdh_blob = kmalloc(input.pdh_cert_len, GFP_KERNEL);
772 	if (!pdh_blob) {
773 		ret = -ENOMEM;
774 		goto e_free;
775 	}
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 e_free:
820 	kfree(data);
821 	return ret;
822 }
823 
824 static long sev_ioctl(struct file *file, unsigned int ioctl, unsigned long arg)
825 {
826 	void __user *argp = (void __user *)arg;
827 	struct sev_issue_cmd input;
828 	int ret = -EFAULT;
829 	bool writable = file->f_mode & FMODE_WRITE;
830 
831 	if (!psp_master || !psp_master->sev_data)
832 		return -ENODEV;
833 
834 	if (ioctl != SEV_ISSUE_CMD)
835 		return -EINVAL;
836 
837 	if (copy_from_user(&input, argp, sizeof(struct sev_issue_cmd)))
838 		return -EFAULT;
839 
840 	if (input.cmd > SEV_MAX)
841 		return -EINVAL;
842 
843 	mutex_lock(&sev_cmd_mutex);
844 
845 	switch (input.cmd) {
846 
847 	case SEV_FACTORY_RESET:
848 		ret = sev_ioctl_do_reset(&input, writable);
849 		break;
850 	case SEV_PLATFORM_STATUS:
851 		ret = sev_ioctl_do_platform_status(&input);
852 		break;
853 	case SEV_PEK_GEN:
854 		ret = sev_ioctl_do_pek_pdh_gen(SEV_CMD_PEK_GEN, &input, writable);
855 		break;
856 	case SEV_PDH_GEN:
857 		ret = sev_ioctl_do_pek_pdh_gen(SEV_CMD_PDH_GEN, &input, writable);
858 		break;
859 	case SEV_PEK_CSR:
860 		ret = sev_ioctl_do_pek_csr(&input, writable);
861 		break;
862 	case SEV_PEK_CERT_IMPORT:
863 		ret = sev_ioctl_do_pek_import(&input, writable);
864 		break;
865 	case SEV_PDH_CERT_EXPORT:
866 		ret = sev_ioctl_do_pdh_export(&input, writable);
867 		break;
868 	case SEV_GET_ID:
869 		pr_warn_once("SEV_GET_ID command is deprecated, use SEV_GET_ID2\n");
870 		ret = sev_ioctl_do_get_id(&input);
871 		break;
872 	case SEV_GET_ID2:
873 		ret = sev_ioctl_do_get_id2(&input);
874 		break;
875 	default:
876 		ret = -EINVAL;
877 		goto out;
878 	}
879 
880 	if (copy_to_user(argp, &input, sizeof(struct sev_issue_cmd)))
881 		ret = -EFAULT;
882 out:
883 	mutex_unlock(&sev_cmd_mutex);
884 
885 	return ret;
886 }
887 
888 static const struct file_operations sev_fops = {
889 	.owner	= THIS_MODULE,
890 	.unlocked_ioctl = sev_ioctl,
891 };
892 
893 int sev_platform_status(struct sev_user_data_status *data, int *error)
894 {
895 	return sev_do_cmd(SEV_CMD_PLATFORM_STATUS, data, error);
896 }
897 EXPORT_SYMBOL_GPL(sev_platform_status);
898 
899 int sev_guest_deactivate(struct sev_data_deactivate *data, int *error)
900 {
901 	return sev_do_cmd(SEV_CMD_DEACTIVATE, data, error);
902 }
903 EXPORT_SYMBOL_GPL(sev_guest_deactivate);
904 
905 int sev_guest_activate(struct sev_data_activate *data, int *error)
906 {
907 	return sev_do_cmd(SEV_CMD_ACTIVATE, data, error);
908 }
909 EXPORT_SYMBOL_GPL(sev_guest_activate);
910 
911 int sev_guest_decommission(struct sev_data_decommission *data, int *error)
912 {
913 	return sev_do_cmd(SEV_CMD_DECOMMISSION, data, error);
914 }
915 EXPORT_SYMBOL_GPL(sev_guest_decommission);
916 
917 int sev_guest_df_flush(int *error)
918 {
919 	return sev_do_cmd(SEV_CMD_DF_FLUSH, NULL, error);
920 }
921 EXPORT_SYMBOL_GPL(sev_guest_df_flush);
922 
923 static void sev_exit(struct kref *ref)
924 {
925 	misc_deregister(&misc_dev->misc);
926 	kfree(misc_dev);
927 	misc_dev = NULL;
928 }
929 
930 static int sev_misc_init(struct sev_device *sev)
931 {
932 	struct device *dev = sev->dev;
933 	int ret;
934 
935 	/*
936 	 * SEV feature support can be detected on multiple devices but the SEV
937 	 * FW commands must be issued on the master. During probe, we do not
938 	 * know the master hence we create /dev/sev on the first device probe.
939 	 * sev_do_cmd() finds the right master device to which to issue the
940 	 * command to the firmware.
941 	 */
942 	if (!misc_dev) {
943 		struct miscdevice *misc;
944 
945 		misc_dev = kzalloc(sizeof(*misc_dev), GFP_KERNEL);
946 		if (!misc_dev)
947 			return -ENOMEM;
948 
949 		misc = &misc_dev->misc;
950 		misc->minor = MISC_DYNAMIC_MINOR;
951 		misc->name = DEVICE_NAME;
952 		misc->fops = &sev_fops;
953 
954 		ret = misc_register(misc);
955 		if (ret)
956 			return ret;
957 
958 		kref_init(&misc_dev->refcount);
959 	} else {
960 		kref_get(&misc_dev->refcount);
961 	}
962 
963 	init_waitqueue_head(&sev->int_queue);
964 	sev->misc = misc_dev;
965 	dev_dbg(dev, "registered SEV device\n");
966 
967 	return 0;
968 }
969 
970 int sev_dev_init(struct psp_device *psp)
971 {
972 	struct device *dev = psp->dev;
973 	struct sev_device *sev;
974 	int ret = -ENOMEM;
975 
976 	if (!boot_cpu_has(X86_FEATURE_SEV)) {
977 		dev_info_once(dev, "SEV: memory encryption not enabled by BIOS\n");
978 		return 0;
979 	}
980 
981 	sev = devm_kzalloc(dev, sizeof(*sev), GFP_KERNEL);
982 	if (!sev)
983 		goto e_err;
984 
985 	psp->sev_data = sev;
986 
987 	sev->dev = dev;
988 	sev->psp = psp;
989 
990 	sev->io_regs = psp->io_regs;
991 
992 	sev->vdata = (struct sev_vdata *)psp->vdata->sev;
993 	if (!sev->vdata) {
994 		ret = -ENODEV;
995 		dev_err(dev, "sev: missing driver data\n");
996 		goto e_err;
997 	}
998 
999 	psp_set_sev_irq_handler(psp, sev_irq_handler, sev);
1000 
1001 	ret = sev_misc_init(sev);
1002 	if (ret)
1003 		goto e_irq;
1004 
1005 	dev_notice(dev, "sev enabled\n");
1006 
1007 	return 0;
1008 
1009 e_irq:
1010 	psp_clear_sev_irq_handler(psp);
1011 e_err:
1012 	psp->sev_data = NULL;
1013 
1014 	dev_notice(dev, "sev initialization failed\n");
1015 
1016 	return ret;
1017 }
1018 
1019 void sev_dev_destroy(struct psp_device *psp)
1020 {
1021 	struct sev_device *sev = psp->sev_data;
1022 
1023 	if (!sev)
1024 		return;
1025 
1026 	if (sev->misc)
1027 		kref_put(&misc_dev->refcount, sev_exit);
1028 
1029 	psp_clear_sev_irq_handler(psp);
1030 }
1031 
1032 int sev_issue_cmd_external_user(struct file *filep, unsigned int cmd,
1033 				void *data, int *error)
1034 {
1035 	if (!filep || filep->f_op != &sev_fops)
1036 		return -EBADF;
1037 
1038 	return sev_do_cmd(cmd, data, error);
1039 }
1040 EXPORT_SYMBOL_GPL(sev_issue_cmd_external_user);
1041 
1042 void sev_pci_init(void)
1043 {
1044 	struct sev_device *sev = psp_master->sev_data;
1045 	struct page *tmr_page;
1046 	int error, rc;
1047 
1048 	if (!sev)
1049 		return;
1050 
1051 	psp_timeout = psp_probe_timeout;
1052 
1053 	if (sev_get_api_version())
1054 		goto err;
1055 
1056 	/*
1057 	 * If platform is not in UNINIT state then firmware upgrade and/or
1058 	 * platform INIT command will fail. These command require UNINIT state.
1059 	 *
1060 	 * In a normal boot we should never run into case where the firmware
1061 	 * is not in UNINIT state on boot. But in case of kexec boot, a reboot
1062 	 * may not go through a typical shutdown sequence and may leave the
1063 	 * firmware in INIT or WORKING state.
1064 	 */
1065 
1066 	if (sev->state != SEV_STATE_UNINIT) {
1067 		sev_platform_shutdown(NULL);
1068 		sev->state = SEV_STATE_UNINIT;
1069 	}
1070 
1071 	if (sev_version_greater_or_equal(0, 15) &&
1072 	    sev_update_firmware(sev->dev) == 0)
1073 		sev_get_api_version();
1074 
1075 	/* Obtain the TMR memory area for SEV-ES use */
1076 	tmr_page = alloc_pages(GFP_KERNEL, get_order(SEV_ES_TMR_SIZE));
1077 	if (tmr_page) {
1078 		sev_es_tmr = page_address(tmr_page);
1079 	} else {
1080 		sev_es_tmr = NULL;
1081 		dev_warn(sev->dev,
1082 			 "SEV: TMR allocation failed, SEV-ES support unavailable\n");
1083 	}
1084 
1085 	/* Initialize the platform */
1086 	rc = sev_platform_init(&error);
1087 	if (rc && (error == SEV_RET_SECURE_DATA_INVALID)) {
1088 		/*
1089 		 * INIT command returned an integrity check failure
1090 		 * status code, meaning that firmware load and
1091 		 * validation of SEV related persistent data has
1092 		 * failed and persistent state has been erased.
1093 		 * Retrying INIT command here should succeed.
1094 		 */
1095 		dev_dbg(sev->dev, "SEV: retrying INIT command");
1096 		rc = sev_platform_init(&error);
1097 	}
1098 
1099 	if (rc) {
1100 		dev_err(sev->dev, "SEV: failed to INIT error %#x\n", error);
1101 		return;
1102 	}
1103 
1104 	dev_info(sev->dev, "SEV API:%d.%d build:%d\n", sev->api_major,
1105 		 sev->api_minor, sev->build);
1106 
1107 	return;
1108 
1109 err:
1110 	psp_master->sev_data = NULL;
1111 }
1112 
1113 void sev_pci_exit(void)
1114 {
1115 	if (!psp_master->sev_data)
1116 		return;
1117 
1118 	sev_platform_shutdown(NULL);
1119 
1120 	if (sev_es_tmr) {
1121 		/* The TMR area was encrypted, flush it from the cache */
1122 		wbinvd_on_all_cpus();
1123 
1124 		free_pages((unsigned long)sev_es_tmr,
1125 			   get_order(SEV_ES_TMR_SIZE));
1126 		sev_es_tmr = NULL;
1127 	}
1128 }
1129