xref: /openbmc/linux/drivers/crypto/ccp/sev-dev.c (revision 78bb17f7)
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 (!access_ok(input.address, input.length) ||
398 	    input.length > SEV_FW_BLOB_MAX_SIZE) {
399 		ret = -EFAULT;
400 		goto e_free;
401 	}
402 
403 	blob = kmalloc(input.length, GFP_KERNEL);
404 	if (!blob) {
405 		ret = -ENOMEM;
406 		goto e_free;
407 	}
408 
409 	data->address = __psp_pa(blob);
410 	data->len = input.length;
411 
412 cmd:
413 	if (sev->state == SEV_STATE_UNINIT) {
414 		ret = __sev_platform_init_locked(&argp->error);
415 		if (ret)
416 			goto e_free_blob;
417 	}
418 
419 	ret = __sev_do_cmd_locked(SEV_CMD_PEK_CSR, data, &argp->error);
420 
421 	 /* If we query the CSR length, FW responded with expected data. */
422 	input.length = data->len;
423 
424 	if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) {
425 		ret = -EFAULT;
426 		goto e_free_blob;
427 	}
428 
429 	if (blob) {
430 		if (copy_to_user((void __user *)input.address, blob, input.length))
431 			ret = -EFAULT;
432 	}
433 
434 e_free_blob:
435 	kfree(blob);
436 e_free:
437 	kfree(data);
438 	return ret;
439 }
440 
441 void *psp_copy_user_blob(u64 __user uaddr, u32 len)
442 {
443 	if (!uaddr || !len)
444 		return ERR_PTR(-EINVAL);
445 
446 	/* verify that blob length does not exceed our limit */
447 	if (len > SEV_FW_BLOB_MAX_SIZE)
448 		return ERR_PTR(-EINVAL);
449 
450 	return memdup_user((void __user *)(uintptr_t)uaddr, len);
451 }
452 EXPORT_SYMBOL_GPL(psp_copy_user_blob);
453 
454 static int sev_get_api_version(void)
455 {
456 	struct sev_device *sev = psp_master->sev_data;
457 	struct sev_user_data_status *status;
458 	int error = 0, ret;
459 
460 	status = &sev->status_cmd_buf;
461 	ret = sev_platform_status(status, &error);
462 	if (ret) {
463 		dev_err(sev->dev,
464 			"SEV: failed to get status. Error: %#x\n", error);
465 		return 1;
466 	}
467 
468 	sev->api_major = status->api_major;
469 	sev->api_minor = status->api_minor;
470 	sev->build = status->build;
471 	sev->state = status->state;
472 
473 	return 0;
474 }
475 
476 static int sev_get_firmware(struct device *dev,
477 			    const struct firmware **firmware)
478 {
479 	char fw_name_specific[SEV_FW_NAME_SIZE];
480 	char fw_name_subset[SEV_FW_NAME_SIZE];
481 
482 	snprintf(fw_name_specific, sizeof(fw_name_specific),
483 		 "amd/amd_sev_fam%.2xh_model%.2xh.sbin",
484 		 boot_cpu_data.x86, boot_cpu_data.x86_model);
485 
486 	snprintf(fw_name_subset, sizeof(fw_name_subset),
487 		 "amd/amd_sev_fam%.2xh_model%.1xxh.sbin",
488 		 boot_cpu_data.x86, (boot_cpu_data.x86_model & 0xf0) >> 4);
489 
490 	/* Check for SEV FW for a particular model.
491 	 * Ex. amd_sev_fam17h_model00h.sbin for Family 17h Model 00h
492 	 *
493 	 * or
494 	 *
495 	 * Check for SEV FW common to a subset of models.
496 	 * Ex. amd_sev_fam17h_model0xh.sbin for
497 	 *     Family 17h Model 00h -- Family 17h Model 0Fh
498 	 *
499 	 * or
500 	 *
501 	 * Fall-back to using generic name: sev.fw
502 	 */
503 	if ((firmware_request_nowarn(firmware, fw_name_specific, dev) >= 0) ||
504 	    (firmware_request_nowarn(firmware, fw_name_subset, dev) >= 0) ||
505 	    (firmware_request_nowarn(firmware, SEV_FW_FILE, dev) >= 0))
506 		return 0;
507 
508 	return -ENOENT;
509 }
510 
511 /* Don't fail if SEV FW couldn't be updated. Continue with existing SEV FW */
512 static int sev_update_firmware(struct device *dev)
513 {
514 	struct sev_data_download_firmware *data;
515 	const struct firmware *firmware;
516 	int ret, error, order;
517 	struct page *p;
518 	u64 data_size;
519 
520 	if (sev_get_firmware(dev, &firmware) == -ENOENT) {
521 		dev_dbg(dev, "No SEV firmware file present\n");
522 		return -1;
523 	}
524 
525 	/*
526 	 * SEV FW expects the physical address given to it to be 32
527 	 * byte aligned. Memory allocated has structure placed at the
528 	 * beginning followed by the firmware being passed to the SEV
529 	 * FW. Allocate enough memory for data structure + alignment
530 	 * padding + SEV FW.
531 	 */
532 	data_size = ALIGN(sizeof(struct sev_data_download_firmware), 32);
533 
534 	order = get_order(firmware->size + data_size);
535 	p = alloc_pages(GFP_KERNEL, order);
536 	if (!p) {
537 		ret = -1;
538 		goto fw_err;
539 	}
540 
541 	/*
542 	 * Copy firmware data to a kernel allocated contiguous
543 	 * memory region.
544 	 */
545 	data = page_address(p);
546 	memcpy(page_address(p) + data_size, firmware->data, firmware->size);
547 
548 	data->address = __psp_pa(page_address(p) + data_size);
549 	data->len = firmware->size;
550 
551 	ret = sev_do_cmd(SEV_CMD_DOWNLOAD_FIRMWARE, data, &error);
552 	if (ret)
553 		dev_dbg(dev, "Failed to update SEV firmware: %#x\n", error);
554 	else
555 		dev_info(dev, "SEV firmware update successful\n");
556 
557 	__free_pages(p, order);
558 
559 fw_err:
560 	release_firmware(firmware);
561 
562 	return ret;
563 }
564 
565 static int sev_ioctl_do_pek_import(struct sev_issue_cmd *argp, bool writable)
566 {
567 	struct sev_device *sev = psp_master->sev_data;
568 	struct sev_user_data_pek_cert_import input;
569 	struct sev_data_pek_cert_import *data;
570 	void *pek_blob, *oca_blob;
571 	int ret;
572 
573 	if (!writable)
574 		return -EPERM;
575 
576 	if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
577 		return -EFAULT;
578 
579 	data = kzalloc(sizeof(*data), GFP_KERNEL);
580 	if (!data)
581 		return -ENOMEM;
582 
583 	/* copy PEK certificate blobs from userspace */
584 	pek_blob = psp_copy_user_blob(input.pek_cert_address, input.pek_cert_len);
585 	if (IS_ERR(pek_blob)) {
586 		ret = PTR_ERR(pek_blob);
587 		goto e_free;
588 	}
589 
590 	data->pek_cert_address = __psp_pa(pek_blob);
591 	data->pek_cert_len = input.pek_cert_len;
592 
593 	/* copy PEK certificate blobs from userspace */
594 	oca_blob = psp_copy_user_blob(input.oca_cert_address, input.oca_cert_len);
595 	if (IS_ERR(oca_blob)) {
596 		ret = PTR_ERR(oca_blob);
597 		goto e_free_pek;
598 	}
599 
600 	data->oca_cert_address = __psp_pa(oca_blob);
601 	data->oca_cert_len = input.oca_cert_len;
602 
603 	/* If platform is not in INIT state then transition it to INIT */
604 	if (sev->state != SEV_STATE_INIT) {
605 		ret = __sev_platform_init_locked(&argp->error);
606 		if (ret)
607 			goto e_free_oca;
608 	}
609 
610 	ret = __sev_do_cmd_locked(SEV_CMD_PEK_CERT_IMPORT, data, &argp->error);
611 
612 e_free_oca:
613 	kfree(oca_blob);
614 e_free_pek:
615 	kfree(pek_blob);
616 e_free:
617 	kfree(data);
618 	return ret;
619 }
620 
621 static int sev_ioctl_do_get_id2(struct sev_issue_cmd *argp)
622 {
623 	struct sev_user_data_get_id2 input;
624 	struct sev_data_get_id *data;
625 	void *id_blob = NULL;
626 	int ret;
627 
628 	/* SEV GET_ID is available from SEV API v0.16 and up */
629 	if (!sev_version_greater_or_equal(0, 16))
630 		return -ENOTSUPP;
631 
632 	if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
633 		return -EFAULT;
634 
635 	/* Check if we have write access to the userspace buffer */
636 	if (input.address &&
637 	    input.length &&
638 	    !access_ok(input.address, input.length))
639 		return -EFAULT;
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((void __user *)input.address,
671 				 id_blob, data->len)) {
672 			ret = -EFAULT;
673 			goto e_free;
674 		}
675 	}
676 
677 e_free:
678 	kfree(id_blob);
679 	kfree(data);
680 
681 	return ret;
682 }
683 
684 static int sev_ioctl_do_get_id(struct sev_issue_cmd *argp)
685 {
686 	struct sev_data_get_id *data;
687 	u64 data_size, user_size;
688 	void *id_blob, *mem;
689 	int ret;
690 
691 	/* SEV GET_ID available from SEV API v0.16 and up */
692 	if (!sev_version_greater_or_equal(0, 16))
693 		return -ENOTSUPP;
694 
695 	/* SEV FW expects the buffer it fills with the ID to be
696 	 * 8-byte aligned. Memory allocated should be enough to
697 	 * hold data structure + alignment padding + memory
698 	 * where SEV FW writes the ID.
699 	 */
700 	data_size = ALIGN(sizeof(struct sev_data_get_id), 8);
701 	user_size = sizeof(struct sev_user_data_get_id);
702 
703 	mem = kzalloc(data_size + user_size, GFP_KERNEL);
704 	if (!mem)
705 		return -ENOMEM;
706 
707 	data = mem;
708 	id_blob = mem + data_size;
709 
710 	data->address = __psp_pa(id_blob);
711 	data->len = user_size;
712 
713 	ret = __sev_do_cmd_locked(SEV_CMD_GET_ID, data, &argp->error);
714 	if (!ret) {
715 		if (copy_to_user((void __user *)argp->data, id_blob, data->len))
716 			ret = -EFAULT;
717 	}
718 
719 	kfree(mem);
720 
721 	return ret;
722 }
723 
724 static int sev_ioctl_do_pdh_export(struct sev_issue_cmd *argp, bool writable)
725 {
726 	struct sev_device *sev = psp_master->sev_data;
727 	struct sev_user_data_pdh_cert_export input;
728 	void *pdh_blob = NULL, *cert_blob = NULL;
729 	struct sev_data_pdh_cert_export *data;
730 	int ret;
731 
732 	/* If platform is not in INIT state then transition it to INIT. */
733 	if (sev->state != SEV_STATE_INIT) {
734 		if (!writable)
735 			return -EPERM;
736 
737 		ret = __sev_platform_init_locked(&argp->error);
738 		if (ret)
739 			return ret;
740 	}
741 
742 	if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
743 		return -EFAULT;
744 
745 	data = kzalloc(sizeof(*data), GFP_KERNEL);
746 	if (!data)
747 		return -ENOMEM;
748 
749 	/* Userspace wants to query the certificate length. */
750 	if (!input.pdh_cert_address ||
751 	    !input.pdh_cert_len ||
752 	    !input.cert_chain_address)
753 		goto cmd;
754 
755 	/* Allocate a physically contiguous buffer to store the PDH blob. */
756 	if ((input.pdh_cert_len > SEV_FW_BLOB_MAX_SIZE) ||
757 	    !access_ok(input.pdh_cert_address, input.pdh_cert_len)) {
758 		ret = -EFAULT;
759 		goto e_free;
760 	}
761 
762 	/* Allocate a physically contiguous buffer to store the cert chain blob. */
763 	if ((input.cert_chain_len > SEV_FW_BLOB_MAX_SIZE) ||
764 	    !access_ok(input.cert_chain_address, input.cert_chain_len)) {
765 		ret = -EFAULT;
766 		goto e_free;
767 	}
768 
769 	pdh_blob = kmalloc(input.pdh_cert_len, GFP_KERNEL);
770 	if (!pdh_blob) {
771 		ret = -ENOMEM;
772 		goto e_free;
773 	}
774 
775 	data->pdh_cert_address = __psp_pa(pdh_blob);
776 	data->pdh_cert_len = input.pdh_cert_len;
777 
778 	cert_blob = kmalloc(input.cert_chain_len, GFP_KERNEL);
779 	if (!cert_blob) {
780 		ret = -ENOMEM;
781 		goto e_free_pdh;
782 	}
783 
784 	data->cert_chain_address = __psp_pa(cert_blob);
785 	data->cert_chain_len = input.cert_chain_len;
786 
787 cmd:
788 	ret = __sev_do_cmd_locked(SEV_CMD_PDH_CERT_EXPORT, data, &argp->error);
789 
790 	/* If we query the length, FW responded with expected data. */
791 	input.cert_chain_len = data->cert_chain_len;
792 	input.pdh_cert_len = data->pdh_cert_len;
793 
794 	if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) {
795 		ret = -EFAULT;
796 		goto e_free_cert;
797 	}
798 
799 	if (pdh_blob) {
800 		if (copy_to_user((void __user *)input.pdh_cert_address,
801 				 pdh_blob, input.pdh_cert_len)) {
802 			ret = -EFAULT;
803 			goto e_free_cert;
804 		}
805 	}
806 
807 	if (cert_blob) {
808 		if (copy_to_user((void __user *)input.cert_chain_address,
809 				 cert_blob, input.cert_chain_len))
810 			ret = -EFAULT;
811 	}
812 
813 e_free_cert:
814 	kfree(cert_blob);
815 e_free_pdh:
816 	kfree(pdh_blob);
817 e_free:
818 	kfree(data);
819 	return ret;
820 }
821 
822 static long sev_ioctl(struct file *file, unsigned int ioctl, unsigned long arg)
823 {
824 	void __user *argp = (void __user *)arg;
825 	struct sev_issue_cmd input;
826 	int ret = -EFAULT;
827 	bool writable = file->f_mode & FMODE_WRITE;
828 
829 	if (!psp_master || !psp_master->sev_data)
830 		return -ENODEV;
831 
832 	if (ioctl != SEV_ISSUE_CMD)
833 		return -EINVAL;
834 
835 	if (copy_from_user(&input, argp, sizeof(struct sev_issue_cmd)))
836 		return -EFAULT;
837 
838 	if (input.cmd > SEV_MAX)
839 		return -EINVAL;
840 
841 	mutex_lock(&sev_cmd_mutex);
842 
843 	switch (input.cmd) {
844 
845 	case SEV_FACTORY_RESET:
846 		ret = sev_ioctl_do_reset(&input, writable);
847 		break;
848 	case SEV_PLATFORM_STATUS:
849 		ret = sev_ioctl_do_platform_status(&input);
850 		break;
851 	case SEV_PEK_GEN:
852 		ret = sev_ioctl_do_pek_pdh_gen(SEV_CMD_PEK_GEN, &input, writable);
853 		break;
854 	case SEV_PDH_GEN:
855 		ret = sev_ioctl_do_pek_pdh_gen(SEV_CMD_PDH_GEN, &input, writable);
856 		break;
857 	case SEV_PEK_CSR:
858 		ret = sev_ioctl_do_pek_csr(&input, writable);
859 		break;
860 	case SEV_PEK_CERT_IMPORT:
861 		ret = sev_ioctl_do_pek_import(&input, writable);
862 		break;
863 	case SEV_PDH_CERT_EXPORT:
864 		ret = sev_ioctl_do_pdh_export(&input, writable);
865 		break;
866 	case SEV_GET_ID:
867 		pr_warn_once("SEV_GET_ID command is deprecated, use SEV_GET_ID2\n");
868 		ret = sev_ioctl_do_get_id(&input);
869 		break;
870 	case SEV_GET_ID2:
871 		ret = sev_ioctl_do_get_id2(&input);
872 		break;
873 	default:
874 		ret = -EINVAL;
875 		goto out;
876 	}
877 
878 	if (copy_to_user(argp, &input, sizeof(struct sev_issue_cmd)))
879 		ret = -EFAULT;
880 out:
881 	mutex_unlock(&sev_cmd_mutex);
882 
883 	return ret;
884 }
885 
886 static const struct file_operations sev_fops = {
887 	.owner	= THIS_MODULE,
888 	.unlocked_ioctl = sev_ioctl,
889 };
890 
891 int sev_platform_status(struct sev_user_data_status *data, int *error)
892 {
893 	return sev_do_cmd(SEV_CMD_PLATFORM_STATUS, data, error);
894 }
895 EXPORT_SYMBOL_GPL(sev_platform_status);
896 
897 int sev_guest_deactivate(struct sev_data_deactivate *data, int *error)
898 {
899 	return sev_do_cmd(SEV_CMD_DEACTIVATE, data, error);
900 }
901 EXPORT_SYMBOL_GPL(sev_guest_deactivate);
902 
903 int sev_guest_activate(struct sev_data_activate *data, int *error)
904 {
905 	return sev_do_cmd(SEV_CMD_ACTIVATE, data, error);
906 }
907 EXPORT_SYMBOL_GPL(sev_guest_activate);
908 
909 int sev_guest_decommission(struct sev_data_decommission *data, int *error)
910 {
911 	return sev_do_cmd(SEV_CMD_DECOMMISSION, data, error);
912 }
913 EXPORT_SYMBOL_GPL(sev_guest_decommission);
914 
915 int sev_guest_df_flush(int *error)
916 {
917 	return sev_do_cmd(SEV_CMD_DF_FLUSH, NULL, error);
918 }
919 EXPORT_SYMBOL_GPL(sev_guest_df_flush);
920 
921 static void sev_exit(struct kref *ref)
922 {
923 	misc_deregister(&misc_dev->misc);
924 	kfree(misc_dev);
925 	misc_dev = NULL;
926 }
927 
928 static int sev_misc_init(struct sev_device *sev)
929 {
930 	struct device *dev = sev->dev;
931 	int ret;
932 
933 	/*
934 	 * SEV feature support can be detected on multiple devices but the SEV
935 	 * FW commands must be issued on the master. During probe, we do not
936 	 * know the master hence we create /dev/sev on the first device probe.
937 	 * sev_do_cmd() finds the right master device to which to issue the
938 	 * command to the firmware.
939 	 */
940 	if (!misc_dev) {
941 		struct miscdevice *misc;
942 
943 		misc_dev = kzalloc(sizeof(*misc_dev), GFP_KERNEL);
944 		if (!misc_dev)
945 			return -ENOMEM;
946 
947 		misc = &misc_dev->misc;
948 		misc->minor = MISC_DYNAMIC_MINOR;
949 		misc->name = DEVICE_NAME;
950 		misc->fops = &sev_fops;
951 
952 		ret = misc_register(misc);
953 		if (ret)
954 			return ret;
955 
956 		kref_init(&misc_dev->refcount);
957 	} else {
958 		kref_get(&misc_dev->refcount);
959 	}
960 
961 	init_waitqueue_head(&sev->int_queue);
962 	sev->misc = misc_dev;
963 	dev_dbg(dev, "registered SEV device\n");
964 
965 	return 0;
966 }
967 
968 int sev_dev_init(struct psp_device *psp)
969 {
970 	struct device *dev = psp->dev;
971 	struct sev_device *sev;
972 	int ret = -ENOMEM;
973 
974 	sev = devm_kzalloc(dev, sizeof(*sev), GFP_KERNEL);
975 	if (!sev)
976 		goto e_err;
977 
978 	psp->sev_data = sev;
979 
980 	sev->dev = dev;
981 	sev->psp = psp;
982 
983 	sev->io_regs = psp->io_regs;
984 
985 	sev->vdata = (struct sev_vdata *)psp->vdata->sev;
986 	if (!sev->vdata) {
987 		ret = -ENODEV;
988 		dev_err(dev, "sev: missing driver data\n");
989 		goto e_err;
990 	}
991 
992 	psp_set_sev_irq_handler(psp, sev_irq_handler, sev);
993 
994 	ret = sev_misc_init(sev);
995 	if (ret)
996 		goto e_irq;
997 
998 	dev_notice(dev, "sev enabled\n");
999 
1000 	return 0;
1001 
1002 e_irq:
1003 	psp_clear_sev_irq_handler(psp);
1004 e_err:
1005 	psp->sev_data = NULL;
1006 
1007 	dev_notice(dev, "sev initialization failed\n");
1008 
1009 	return ret;
1010 }
1011 
1012 void sev_dev_destroy(struct psp_device *psp)
1013 {
1014 	struct sev_device *sev = psp->sev_data;
1015 
1016 	if (!sev)
1017 		return;
1018 
1019 	if (sev->misc)
1020 		kref_put(&misc_dev->refcount, sev_exit);
1021 
1022 	psp_clear_sev_irq_handler(psp);
1023 }
1024 
1025 int sev_issue_cmd_external_user(struct file *filep, unsigned int cmd,
1026 				void *data, int *error)
1027 {
1028 	if (!filep || filep->f_op != &sev_fops)
1029 		return -EBADF;
1030 
1031 	return sev_do_cmd(cmd, data, error);
1032 }
1033 EXPORT_SYMBOL_GPL(sev_issue_cmd_external_user);
1034 
1035 void sev_pci_init(void)
1036 {
1037 	struct sev_device *sev = psp_master->sev_data;
1038 	struct page *tmr_page;
1039 	int error, rc;
1040 
1041 	if (!sev)
1042 		return;
1043 
1044 	psp_timeout = psp_probe_timeout;
1045 
1046 	if (sev_get_api_version())
1047 		goto err;
1048 
1049 	/*
1050 	 * If platform is not in UNINIT state then firmware upgrade and/or
1051 	 * platform INIT command will fail. These command require UNINIT state.
1052 	 *
1053 	 * In a normal boot we should never run into case where the firmware
1054 	 * is not in UNINIT state on boot. But in case of kexec boot, a reboot
1055 	 * may not go through a typical shutdown sequence and may leave the
1056 	 * firmware in INIT or WORKING state.
1057 	 */
1058 
1059 	if (sev->state != SEV_STATE_UNINIT) {
1060 		sev_platform_shutdown(NULL);
1061 		sev->state = SEV_STATE_UNINIT;
1062 	}
1063 
1064 	if (sev_version_greater_or_equal(0, 15) &&
1065 	    sev_update_firmware(sev->dev) == 0)
1066 		sev_get_api_version();
1067 
1068 	/* Obtain the TMR memory area for SEV-ES use */
1069 	tmr_page = alloc_pages(GFP_KERNEL, get_order(SEV_ES_TMR_SIZE));
1070 	if (tmr_page) {
1071 		sev_es_tmr = page_address(tmr_page);
1072 	} else {
1073 		sev_es_tmr = NULL;
1074 		dev_warn(sev->dev,
1075 			 "SEV: TMR allocation failed, SEV-ES support unavailable\n");
1076 	}
1077 
1078 	/* Initialize the platform */
1079 	rc = sev_platform_init(&error);
1080 	if (rc && (error == SEV_RET_SECURE_DATA_INVALID)) {
1081 		/*
1082 		 * INIT command returned an integrity check failure
1083 		 * status code, meaning that firmware load and
1084 		 * validation of SEV related persistent data has
1085 		 * failed and persistent state has been erased.
1086 		 * Retrying INIT command here should succeed.
1087 		 */
1088 		dev_dbg(sev->dev, "SEV: retrying INIT command");
1089 		rc = sev_platform_init(&error);
1090 	}
1091 
1092 	if (rc) {
1093 		dev_err(sev->dev, "SEV: failed to INIT error %#x\n", error);
1094 		return;
1095 	}
1096 
1097 	dev_info(sev->dev, "SEV API:%d.%d build:%d\n", sev->api_major,
1098 		 sev->api_minor, sev->build);
1099 
1100 	return;
1101 
1102 err:
1103 	psp_master->sev_data = NULL;
1104 }
1105 
1106 void sev_pci_exit(void)
1107 {
1108 	if (!psp_master->sev_data)
1109 		return;
1110 
1111 	sev_platform_shutdown(NULL);
1112 
1113 	if (sev_es_tmr) {
1114 		/* The TMR area was encrypted, flush it from the cache */
1115 		wbinvd_on_all_cpus();
1116 
1117 		free_pages((unsigned long)sev_es_tmr,
1118 			   get_order(SEV_ES_TMR_SIZE));
1119 		sev_es_tmr = NULL;
1120 	}
1121 }
1122