xref: /linux/drivers/crypto/ccp/sev-dev.c (revision 1d18101a644e6ece450d5b0a93f21a71a21b6222)
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/bitfield.h>
11 #include <linux/module.h>
12 #include <linux/kernel.h>
13 #include <linux/kthread.h>
14 #include <linux/sched.h>
15 #include <linux/interrupt.h>
16 #include <linux/spinlock.h>
17 #include <linux/spinlock_types.h>
18 #include <linux/types.h>
19 #include <linux/mutex.h>
20 #include <linux/delay.h>
21 #include <linux/hw_random.h>
22 #include <linux/ccp.h>
23 #include <linux/firmware.h>
24 #include <linux/panic_notifier.h>
25 #include <linux/gfp.h>
26 #include <linux/cpufeature.h>
27 #include <linux/fs.h>
28 #include <linux/fs_struct.h>
29 #include <linux/psp.h>
30 #include <linux/amd-iommu.h>
31 #include <linux/crash_dump.h>
32 
33 #include <asm/smp.h>
34 #include <asm/cacheflush.h>
35 #include <asm/e820/types.h>
36 #include <asm/sev.h>
37 #include <asm/msr.h>
38 
39 #include "psp-dev.h"
40 #include "sev-dev.h"
41 
42 #define DEVICE_NAME		"sev"
43 #define SEV_FW_FILE		"amd/sev.fw"
44 #define SEV_FW_NAME_SIZE	64
45 
46 /* Minimum firmware version required for the SEV-SNP support */
47 #define SNP_MIN_API_MAJOR	1
48 #define SNP_MIN_API_MINOR	51
49 
50 /*
51  * Maximum number of firmware-writable buffers that might be specified
52  * in the parameters of a legacy SEV command buffer.
53  */
54 #define CMD_BUF_FW_WRITABLE_MAX 2
55 
56 /* Leave room in the descriptor array for an end-of-list indicator. */
57 #define CMD_BUF_DESC_MAX (CMD_BUF_FW_WRITABLE_MAX + 1)
58 
59 static DEFINE_MUTEX(sev_cmd_mutex);
60 static struct sev_misc_dev *misc_dev;
61 
62 static int psp_cmd_timeout = 100;
63 module_param(psp_cmd_timeout, int, 0644);
64 MODULE_PARM_DESC(psp_cmd_timeout, " default timeout value, in seconds, for PSP commands");
65 
66 static int psp_probe_timeout = 5;
67 module_param(psp_probe_timeout, int, 0644);
68 MODULE_PARM_DESC(psp_probe_timeout, " default timeout value, in seconds, during PSP device probe");
69 
70 static char *init_ex_path;
71 module_param(init_ex_path, charp, 0444);
72 MODULE_PARM_DESC(init_ex_path, " Path for INIT_EX data; if set try INIT_EX");
73 
74 static bool psp_init_on_probe = true;
75 module_param(psp_init_on_probe, bool, 0444);
76 MODULE_PARM_DESC(psp_init_on_probe, "  if true, the PSP will be initialized on module init. Else the PSP will be initialized on the first command requiring it");
77 
78 MODULE_FIRMWARE("amd/amd_sev_fam17h_model0xh.sbin"); /* 1st gen EPYC */
79 MODULE_FIRMWARE("amd/amd_sev_fam17h_model3xh.sbin"); /* 2nd gen EPYC */
80 MODULE_FIRMWARE("amd/amd_sev_fam19h_model0xh.sbin"); /* 3rd gen EPYC */
81 MODULE_FIRMWARE("amd/amd_sev_fam19h_model1xh.sbin"); /* 4th gen EPYC */
82 
83 static bool psp_dead;
84 static int psp_timeout;
85 
86 enum snp_hv_fixed_pages_state {
87 	ALLOCATED,
88 	HV_FIXED,
89 };
90 
91 struct snp_hv_fixed_pages_entry {
92 	struct list_head list;
93 	struct page *page;
94 	unsigned int order;
95 	bool free;
96 	enum snp_hv_fixed_pages_state page_state;
97 };
98 
99 static LIST_HEAD(snp_hv_fixed_pages);
100 
101 /* Trusted Memory Region (TMR):
102  *   The TMR is a 1MB area that must be 1MB aligned.  Use the page allocator
103  *   to allocate the memory, which will return aligned memory for the specified
104  *   allocation order.
105  *
106  * When SEV-SNP is enabled the TMR needs to be 2MB aligned and 2MB sized.
107  */
108 #define SEV_TMR_SIZE		(1024 * 1024)
109 #define SNP_TMR_SIZE		(2 * 1024 * 1024)
110 
111 static void *sev_es_tmr;
112 static size_t sev_es_tmr_size = SEV_TMR_SIZE;
113 
114 /* INIT_EX NV Storage:
115  *   The NV Storage is a 32Kb area and must be 4Kb page aligned.  Use the page
116  *   allocator to allocate the memory, which will return aligned memory for the
117  *   specified allocation order.
118  */
119 #define NV_LENGTH (32 * 1024)
120 static void *sev_init_ex_buffer;
121 
122 /*
123  * SEV_DATA_RANGE_LIST:
124  *   Array containing range of pages that firmware transitions to HV-fixed
125  *   page state.
126  */
127 static struct sev_data_range_list *snp_range_list;
128 
129 static void __sev_firmware_shutdown(struct sev_device *sev, bool panic);
130 
131 static int snp_shutdown_on_panic(struct notifier_block *nb,
132 				 unsigned long reason, void *arg);
133 
134 static struct notifier_block snp_panic_notifier = {
135 	.notifier_call = snp_shutdown_on_panic,
136 };
137 
sev_version_greater_or_equal(u8 maj,u8 min)138 static inline bool sev_version_greater_or_equal(u8 maj, u8 min)
139 {
140 	struct sev_device *sev = psp_master->sev_data;
141 
142 	if (sev->api_major > maj)
143 		return true;
144 
145 	if (sev->api_major == maj && sev->api_minor >= min)
146 		return true;
147 
148 	return false;
149 }
150 
sev_irq_handler(int irq,void * data,unsigned int status)151 static void sev_irq_handler(int irq, void *data, unsigned int status)
152 {
153 	struct sev_device *sev = data;
154 	int reg;
155 
156 	/* Check if it is command completion: */
157 	if (!(status & SEV_CMD_COMPLETE))
158 		return;
159 
160 	/* Check if it is SEV command completion: */
161 	reg = ioread32(sev->io_regs + sev->vdata->cmdresp_reg);
162 	if (FIELD_GET(PSP_CMDRESP_RESP, reg)) {
163 		sev->int_rcvd = 1;
164 		wake_up(&sev->int_queue);
165 	}
166 }
167 
sev_wait_cmd_ioc(struct sev_device * sev,unsigned int * reg,unsigned int timeout)168 static int sev_wait_cmd_ioc(struct sev_device *sev,
169 			    unsigned int *reg, unsigned int timeout)
170 {
171 	int ret;
172 
173 	/*
174 	 * If invoked during panic handling, local interrupts are disabled,
175 	 * so the PSP command completion interrupt can't be used. Poll for
176 	 * PSP command completion instead.
177 	 */
178 	if (irqs_disabled()) {
179 		unsigned long timeout_usecs = (timeout * USEC_PER_SEC) / 10;
180 
181 		/* Poll for SEV command completion: */
182 		while (timeout_usecs--) {
183 			*reg = ioread32(sev->io_regs + sev->vdata->cmdresp_reg);
184 			if (*reg & PSP_CMDRESP_RESP)
185 				return 0;
186 
187 			udelay(10);
188 		}
189 		return -ETIMEDOUT;
190 	}
191 
192 	ret = wait_event_timeout(sev->int_queue,
193 			sev->int_rcvd, timeout * HZ);
194 	if (!ret)
195 		return -ETIMEDOUT;
196 
197 	*reg = ioread32(sev->io_regs + sev->vdata->cmdresp_reg);
198 
199 	return 0;
200 }
201 
sev_cmd_buffer_len(int cmd)202 static int sev_cmd_buffer_len(int cmd)
203 {
204 	switch (cmd) {
205 	case SEV_CMD_INIT:			return sizeof(struct sev_data_init);
206 	case SEV_CMD_INIT_EX:                   return sizeof(struct sev_data_init_ex);
207 	case SEV_CMD_SNP_SHUTDOWN_EX:		return sizeof(struct sev_data_snp_shutdown_ex);
208 	case SEV_CMD_SNP_INIT_EX:		return sizeof(struct sev_data_snp_init_ex);
209 	case SEV_CMD_PLATFORM_STATUS:		return sizeof(struct sev_user_data_status);
210 	case SEV_CMD_PEK_CSR:			return sizeof(struct sev_data_pek_csr);
211 	case SEV_CMD_PEK_CERT_IMPORT:		return sizeof(struct sev_data_pek_cert_import);
212 	case SEV_CMD_PDH_CERT_EXPORT:		return sizeof(struct sev_data_pdh_cert_export);
213 	case SEV_CMD_LAUNCH_START:		return sizeof(struct sev_data_launch_start);
214 	case SEV_CMD_LAUNCH_UPDATE_DATA:	return sizeof(struct sev_data_launch_update_data);
215 	case SEV_CMD_LAUNCH_UPDATE_VMSA:	return sizeof(struct sev_data_launch_update_vmsa);
216 	case SEV_CMD_LAUNCH_FINISH:		return sizeof(struct sev_data_launch_finish);
217 	case SEV_CMD_LAUNCH_MEASURE:		return sizeof(struct sev_data_launch_measure);
218 	case SEV_CMD_ACTIVATE:			return sizeof(struct sev_data_activate);
219 	case SEV_CMD_DEACTIVATE:		return sizeof(struct sev_data_deactivate);
220 	case SEV_CMD_DECOMMISSION:		return sizeof(struct sev_data_decommission);
221 	case SEV_CMD_GUEST_STATUS:		return sizeof(struct sev_data_guest_status);
222 	case SEV_CMD_DBG_DECRYPT:		return sizeof(struct sev_data_dbg);
223 	case SEV_CMD_DBG_ENCRYPT:		return sizeof(struct sev_data_dbg);
224 	case SEV_CMD_SEND_START:		return sizeof(struct sev_data_send_start);
225 	case SEV_CMD_SEND_UPDATE_DATA:		return sizeof(struct sev_data_send_update_data);
226 	case SEV_CMD_SEND_UPDATE_VMSA:		return sizeof(struct sev_data_send_update_vmsa);
227 	case SEV_CMD_SEND_FINISH:		return sizeof(struct sev_data_send_finish);
228 	case SEV_CMD_RECEIVE_START:		return sizeof(struct sev_data_receive_start);
229 	case SEV_CMD_RECEIVE_FINISH:		return sizeof(struct sev_data_receive_finish);
230 	case SEV_CMD_RECEIVE_UPDATE_DATA:	return sizeof(struct sev_data_receive_update_data);
231 	case SEV_CMD_RECEIVE_UPDATE_VMSA:	return sizeof(struct sev_data_receive_update_vmsa);
232 	case SEV_CMD_LAUNCH_UPDATE_SECRET:	return sizeof(struct sev_data_launch_secret);
233 	case SEV_CMD_DOWNLOAD_FIRMWARE:		return sizeof(struct sev_data_download_firmware);
234 	case SEV_CMD_GET_ID:			return sizeof(struct sev_data_get_id);
235 	case SEV_CMD_ATTESTATION_REPORT:	return sizeof(struct sev_data_attestation_report);
236 	case SEV_CMD_SEND_CANCEL:		return sizeof(struct sev_data_send_cancel);
237 	case SEV_CMD_SNP_GCTX_CREATE:		return sizeof(struct sev_data_snp_addr);
238 	case SEV_CMD_SNP_LAUNCH_START:		return sizeof(struct sev_data_snp_launch_start);
239 	case SEV_CMD_SNP_LAUNCH_UPDATE:		return sizeof(struct sev_data_snp_launch_update);
240 	case SEV_CMD_SNP_ACTIVATE:		return sizeof(struct sev_data_snp_activate);
241 	case SEV_CMD_SNP_DECOMMISSION:		return sizeof(struct sev_data_snp_addr);
242 	case SEV_CMD_SNP_PAGE_RECLAIM:		return sizeof(struct sev_data_snp_page_reclaim);
243 	case SEV_CMD_SNP_GUEST_STATUS:		return sizeof(struct sev_data_snp_guest_status);
244 	case SEV_CMD_SNP_LAUNCH_FINISH:		return sizeof(struct sev_data_snp_launch_finish);
245 	case SEV_CMD_SNP_DBG_DECRYPT:		return sizeof(struct sev_data_snp_dbg);
246 	case SEV_CMD_SNP_DBG_ENCRYPT:		return sizeof(struct sev_data_snp_dbg);
247 	case SEV_CMD_SNP_PAGE_UNSMASH:		return sizeof(struct sev_data_snp_page_unsmash);
248 	case SEV_CMD_SNP_PLATFORM_STATUS:	return sizeof(struct sev_data_snp_addr);
249 	case SEV_CMD_SNP_GUEST_REQUEST:		return sizeof(struct sev_data_snp_guest_request);
250 	case SEV_CMD_SNP_CONFIG:		return sizeof(struct sev_user_data_snp_config);
251 	case SEV_CMD_SNP_COMMIT:		return sizeof(struct sev_data_snp_commit);
252 	case SEV_CMD_SNP_FEATURE_INFO:		return sizeof(struct sev_data_snp_feature_info);
253 	case SEV_CMD_SNP_VLEK_LOAD:		return sizeof(struct sev_user_data_snp_vlek_load);
254 	default:				return 0;
255 	}
256 
257 	return 0;
258 }
259 
open_file_as_root(const char * filename,int flags,umode_t mode)260 static struct file *open_file_as_root(const char *filename, int flags, umode_t mode)
261 {
262 	struct path root __free(path_put) = {};
263 
264 	task_lock(&init_task);
265 	get_fs_root(init_task.fs, &root);
266 	task_unlock(&init_task);
267 
268 	CLASS(prepare_creds, cred)();
269 	if (!cred)
270 		return ERR_PTR(-ENOMEM);
271 
272 	cred->fsuid = GLOBAL_ROOT_UID;
273 
274 	scoped_with_creds(cred)
275 		return file_open_root(&root, filename, flags, mode);
276 }
277 
sev_read_init_ex_file(void)278 static int sev_read_init_ex_file(void)
279 {
280 	struct sev_device *sev = psp_master->sev_data;
281 	struct file *fp;
282 	ssize_t nread;
283 
284 	lockdep_assert_held(&sev_cmd_mutex);
285 
286 	if (!sev_init_ex_buffer)
287 		return -EOPNOTSUPP;
288 
289 	fp = open_file_as_root(init_ex_path, O_RDONLY, 0);
290 	if (IS_ERR(fp)) {
291 		int ret = PTR_ERR(fp);
292 
293 		if (ret == -ENOENT) {
294 			dev_info(sev->dev,
295 				"SEV: %s does not exist and will be created later.\n",
296 				init_ex_path);
297 			ret = 0;
298 		} else {
299 			dev_err(sev->dev,
300 				"SEV: could not open %s for read, error %d\n",
301 				init_ex_path, ret);
302 		}
303 		return ret;
304 	}
305 
306 	nread = kernel_read(fp, sev_init_ex_buffer, NV_LENGTH, NULL);
307 	if (nread != NV_LENGTH) {
308 		dev_info(sev->dev,
309 			"SEV: could not read %u bytes to non volatile memory area, ret %ld\n",
310 			NV_LENGTH, nread);
311 	}
312 
313 	dev_dbg(sev->dev, "SEV: read %ld bytes from NV file\n", nread);
314 	filp_close(fp, NULL);
315 
316 	return 0;
317 }
318 
sev_write_init_ex_file(void)319 static int sev_write_init_ex_file(void)
320 {
321 	struct sev_device *sev = psp_master->sev_data;
322 	struct file *fp;
323 	loff_t offset = 0;
324 	ssize_t nwrite;
325 
326 	lockdep_assert_held(&sev_cmd_mutex);
327 
328 	if (!sev_init_ex_buffer)
329 		return 0;
330 
331 	fp = open_file_as_root(init_ex_path, O_CREAT | O_WRONLY, 0600);
332 	if (IS_ERR(fp)) {
333 		int ret = PTR_ERR(fp);
334 
335 		dev_err(sev->dev,
336 			"SEV: could not open file for write, error %d\n",
337 			ret);
338 		return ret;
339 	}
340 
341 	nwrite = kernel_write(fp, sev_init_ex_buffer, NV_LENGTH, &offset);
342 	vfs_fsync(fp, 0);
343 	filp_close(fp, NULL);
344 
345 	if (nwrite != NV_LENGTH) {
346 		dev_err(sev->dev,
347 			"SEV: failed to write %u bytes to non volatile memory area, ret %ld\n",
348 			NV_LENGTH, nwrite);
349 		return -EIO;
350 	}
351 
352 	dev_dbg(sev->dev, "SEV: write successful to NV file\n");
353 
354 	return 0;
355 }
356 
sev_write_init_ex_file_if_required(int cmd_id)357 static int sev_write_init_ex_file_if_required(int cmd_id)
358 {
359 	lockdep_assert_held(&sev_cmd_mutex);
360 
361 	if (!sev_init_ex_buffer)
362 		return 0;
363 
364 	/*
365 	 * Only a few platform commands modify the SPI/NV area, but none of the
366 	 * non-platform commands do. Only INIT(_EX), PLATFORM_RESET, PEK_GEN,
367 	 * PEK_CERT_IMPORT, and PDH_GEN do.
368 	 */
369 	switch (cmd_id) {
370 	case SEV_CMD_FACTORY_RESET:
371 	case SEV_CMD_INIT_EX:
372 	case SEV_CMD_PDH_GEN:
373 	case SEV_CMD_PEK_CERT_IMPORT:
374 	case SEV_CMD_PEK_GEN:
375 		break;
376 	default:
377 		return 0;
378 	}
379 
380 	return sev_write_init_ex_file();
381 }
382 
383 /*
384  * snp_reclaim_pages() needs __sev_do_cmd_locked(), and __sev_do_cmd_locked()
385  * needs snp_reclaim_pages(), so a forward declaration is needed.
386  */
387 static int __sev_do_cmd_locked(int cmd, void *data, int *psp_ret);
388 
snp_reclaim_pages(unsigned long paddr,unsigned int npages,bool locked)389 static int snp_reclaim_pages(unsigned long paddr, unsigned int npages, bool locked)
390 {
391 	int ret, err, i;
392 
393 	paddr = __sme_clr(ALIGN_DOWN(paddr, PAGE_SIZE));
394 
395 	for (i = 0; i < npages; i++, paddr += PAGE_SIZE) {
396 		struct sev_data_snp_page_reclaim data = {0};
397 
398 		data.paddr = paddr;
399 
400 		if (locked)
401 			ret = __sev_do_cmd_locked(SEV_CMD_SNP_PAGE_RECLAIM, &data, &err);
402 		else
403 			ret = sev_do_cmd(SEV_CMD_SNP_PAGE_RECLAIM, &data, &err);
404 
405 		if (ret)
406 			goto cleanup;
407 
408 		ret = rmp_make_shared(__phys_to_pfn(paddr), PG_LEVEL_4K);
409 		if (ret)
410 			goto cleanup;
411 	}
412 
413 	return 0;
414 
415 cleanup:
416 	/*
417 	 * If there was a failure reclaiming the page then it is no longer safe
418 	 * to release it back to the system; leak it instead.
419 	 */
420 	snp_leak_pages(__phys_to_pfn(paddr), npages - i);
421 	return ret;
422 }
423 
rmp_mark_pages_firmware(unsigned long paddr,unsigned int npages,bool locked)424 static int rmp_mark_pages_firmware(unsigned long paddr, unsigned int npages, bool locked)
425 {
426 	unsigned long pfn = __sme_clr(paddr) >> PAGE_SHIFT;
427 	int rc, i;
428 
429 	for (i = 0; i < npages; i++, pfn++) {
430 		rc = rmp_make_private(pfn, 0, PG_LEVEL_4K, 0, true);
431 		if (rc)
432 			goto cleanup;
433 	}
434 
435 	return 0;
436 
437 cleanup:
438 	/*
439 	 * Try unrolling the firmware state changes by
440 	 * reclaiming the pages which were already changed to the
441 	 * firmware state.
442 	 */
443 	snp_reclaim_pages(paddr, i, locked);
444 
445 	return rc;
446 }
447 
__snp_alloc_firmware_pages(gfp_t gfp_mask,int order,bool locked)448 static struct page *__snp_alloc_firmware_pages(gfp_t gfp_mask, int order, bool locked)
449 {
450 	unsigned long npages = 1ul << order, paddr;
451 	struct sev_device *sev;
452 	struct page *page;
453 
454 	if (!psp_master || !psp_master->sev_data)
455 		return NULL;
456 
457 	page = alloc_pages(gfp_mask, order);
458 	if (!page)
459 		return NULL;
460 
461 	/* If SEV-SNP is initialized then add the page in RMP table. */
462 	sev = psp_master->sev_data;
463 	if (!sev->snp_initialized)
464 		return page;
465 
466 	paddr = __pa((unsigned long)page_address(page));
467 	if (rmp_mark_pages_firmware(paddr, npages, locked))
468 		return NULL;
469 
470 	return page;
471 }
472 
snp_alloc_firmware_page(gfp_t gfp_mask)473 void *snp_alloc_firmware_page(gfp_t gfp_mask)
474 {
475 	struct page *page;
476 
477 	page = __snp_alloc_firmware_pages(gfp_mask, 0, false);
478 
479 	return page ? page_address(page) : NULL;
480 }
481 EXPORT_SYMBOL_GPL(snp_alloc_firmware_page);
482 
__snp_free_firmware_pages(struct page * page,int order,bool locked)483 static void __snp_free_firmware_pages(struct page *page, int order, bool locked)
484 {
485 	struct sev_device *sev = psp_master->sev_data;
486 	unsigned long paddr, npages = 1ul << order;
487 
488 	if (!page)
489 		return;
490 
491 	paddr = __pa((unsigned long)page_address(page));
492 	if (sev->snp_initialized &&
493 	    snp_reclaim_pages(paddr, npages, locked))
494 		return;
495 
496 	__free_pages(page, order);
497 }
498 
snp_free_firmware_page(void * addr)499 void snp_free_firmware_page(void *addr)
500 {
501 	if (!addr)
502 		return;
503 
504 	__snp_free_firmware_pages(virt_to_page(addr), 0, false);
505 }
506 EXPORT_SYMBOL_GPL(snp_free_firmware_page);
507 
sev_fw_alloc(unsigned long len)508 static void *sev_fw_alloc(unsigned long len)
509 {
510 	struct page *page;
511 
512 	page = __snp_alloc_firmware_pages(GFP_KERNEL, get_order(len), true);
513 	if (!page)
514 		return NULL;
515 
516 	return page_address(page);
517 }
518 
519 /**
520  * struct cmd_buf_desc - descriptors for managing legacy SEV command address
521  * parameters corresponding to buffers that may be written to by firmware.
522  *
523  * @paddr_ptr:  pointer to the address parameter in the command buffer which may
524  *              need to be saved/restored depending on whether a bounce buffer
525  *              is used. In the case of a bounce buffer, the command buffer
526  *              needs to be updated with the address of the new bounce buffer
527  *              snp_map_cmd_buf_desc() has allocated specifically for it. Must
528  *              be NULL if this descriptor is only an end-of-list indicator.
529  *
530  * @paddr_orig: storage for the original address parameter, which can be used to
531  *              restore the original value in @paddr_ptr in cases where it is
532  *              replaced with the address of a bounce buffer.
533  *
534  * @len: length of buffer located at the address originally stored at @paddr_ptr
535  *
536  * @guest_owned: true if the address corresponds to guest-owned pages, in which
537  *               case bounce buffers are not needed.
538  */
539 struct cmd_buf_desc {
540 	u64 *paddr_ptr;
541 	u64 paddr_orig;
542 	u32 len;
543 	bool guest_owned;
544 };
545 
546 /*
547  * If a legacy SEV command parameter is a memory address, those pages in
548  * turn need to be transitioned to/from firmware-owned before/after
549  * executing the firmware command.
550  *
551  * Additionally, in cases where those pages are not guest-owned, a bounce
552  * buffer is needed in place of the original memory address parameter.
553  *
554  * A set of descriptors are used to keep track of this handling, and
555  * initialized here based on the specific commands being executed.
556  */
snp_populate_cmd_buf_desc_list(int cmd,void * cmd_buf,struct cmd_buf_desc * desc_list)557 static void snp_populate_cmd_buf_desc_list(int cmd, void *cmd_buf,
558 					   struct cmd_buf_desc *desc_list)
559 {
560 	switch (cmd) {
561 	case SEV_CMD_PDH_CERT_EXPORT: {
562 		struct sev_data_pdh_cert_export *data = cmd_buf;
563 
564 		desc_list[0].paddr_ptr = &data->pdh_cert_address;
565 		desc_list[0].len = data->pdh_cert_len;
566 		desc_list[1].paddr_ptr = &data->cert_chain_address;
567 		desc_list[1].len = data->cert_chain_len;
568 		break;
569 	}
570 	case SEV_CMD_GET_ID: {
571 		struct sev_data_get_id *data = cmd_buf;
572 
573 		desc_list[0].paddr_ptr = &data->address;
574 		desc_list[0].len = data->len;
575 		break;
576 	}
577 	case SEV_CMD_PEK_CSR: {
578 		struct sev_data_pek_csr *data = cmd_buf;
579 
580 		desc_list[0].paddr_ptr = &data->address;
581 		desc_list[0].len = data->len;
582 		break;
583 	}
584 	case SEV_CMD_LAUNCH_UPDATE_DATA: {
585 		struct sev_data_launch_update_data *data = cmd_buf;
586 
587 		desc_list[0].paddr_ptr = &data->address;
588 		desc_list[0].len = data->len;
589 		desc_list[0].guest_owned = true;
590 		break;
591 	}
592 	case SEV_CMD_LAUNCH_UPDATE_VMSA: {
593 		struct sev_data_launch_update_vmsa *data = cmd_buf;
594 
595 		desc_list[0].paddr_ptr = &data->address;
596 		desc_list[0].len = data->len;
597 		desc_list[0].guest_owned = true;
598 		break;
599 	}
600 	case SEV_CMD_LAUNCH_MEASURE: {
601 		struct sev_data_launch_measure *data = cmd_buf;
602 
603 		desc_list[0].paddr_ptr = &data->address;
604 		desc_list[0].len = data->len;
605 		break;
606 	}
607 	case SEV_CMD_LAUNCH_UPDATE_SECRET: {
608 		struct sev_data_launch_secret *data = cmd_buf;
609 
610 		desc_list[0].paddr_ptr = &data->guest_address;
611 		desc_list[0].len = data->guest_len;
612 		desc_list[0].guest_owned = true;
613 		break;
614 	}
615 	case SEV_CMD_DBG_DECRYPT: {
616 		struct sev_data_dbg *data = cmd_buf;
617 
618 		desc_list[0].paddr_ptr = &data->dst_addr;
619 		desc_list[0].len = data->len;
620 		desc_list[0].guest_owned = true;
621 		break;
622 	}
623 	case SEV_CMD_DBG_ENCRYPT: {
624 		struct sev_data_dbg *data = cmd_buf;
625 
626 		desc_list[0].paddr_ptr = &data->dst_addr;
627 		desc_list[0].len = data->len;
628 		desc_list[0].guest_owned = true;
629 		break;
630 	}
631 	case SEV_CMD_ATTESTATION_REPORT: {
632 		struct sev_data_attestation_report *data = cmd_buf;
633 
634 		desc_list[0].paddr_ptr = &data->address;
635 		desc_list[0].len = data->len;
636 		break;
637 	}
638 	case SEV_CMD_SEND_START: {
639 		struct sev_data_send_start *data = cmd_buf;
640 
641 		desc_list[0].paddr_ptr = &data->session_address;
642 		desc_list[0].len = data->session_len;
643 		break;
644 	}
645 	case SEV_CMD_SEND_UPDATE_DATA: {
646 		struct sev_data_send_update_data *data = cmd_buf;
647 
648 		desc_list[0].paddr_ptr = &data->hdr_address;
649 		desc_list[0].len = data->hdr_len;
650 		desc_list[1].paddr_ptr = &data->trans_address;
651 		desc_list[1].len = data->trans_len;
652 		break;
653 	}
654 	case SEV_CMD_SEND_UPDATE_VMSA: {
655 		struct sev_data_send_update_vmsa *data = cmd_buf;
656 
657 		desc_list[0].paddr_ptr = &data->hdr_address;
658 		desc_list[0].len = data->hdr_len;
659 		desc_list[1].paddr_ptr = &data->trans_address;
660 		desc_list[1].len = data->trans_len;
661 		break;
662 	}
663 	case SEV_CMD_RECEIVE_UPDATE_DATA: {
664 		struct sev_data_receive_update_data *data = cmd_buf;
665 
666 		desc_list[0].paddr_ptr = &data->guest_address;
667 		desc_list[0].len = data->guest_len;
668 		desc_list[0].guest_owned = true;
669 		break;
670 	}
671 	case SEV_CMD_RECEIVE_UPDATE_VMSA: {
672 		struct sev_data_receive_update_vmsa *data = cmd_buf;
673 
674 		desc_list[0].paddr_ptr = &data->guest_address;
675 		desc_list[0].len = data->guest_len;
676 		desc_list[0].guest_owned = true;
677 		break;
678 	}
679 	default:
680 		break;
681 	}
682 }
683 
snp_map_cmd_buf_desc(struct cmd_buf_desc * desc)684 static int snp_map_cmd_buf_desc(struct cmd_buf_desc *desc)
685 {
686 	unsigned int npages;
687 
688 	if (!desc->len)
689 		return 0;
690 
691 	/* Allocate a bounce buffer if this isn't a guest owned page. */
692 	if (!desc->guest_owned) {
693 		struct page *page;
694 
695 		page = alloc_pages(GFP_KERNEL_ACCOUNT, get_order(desc->len));
696 		if (!page) {
697 			pr_warn("Failed to allocate bounce buffer for SEV legacy command.\n");
698 			return -ENOMEM;
699 		}
700 
701 		desc->paddr_orig = *desc->paddr_ptr;
702 		*desc->paddr_ptr = __psp_pa(page_to_virt(page));
703 	}
704 
705 	npages = PAGE_ALIGN(desc->len) >> PAGE_SHIFT;
706 
707 	/* Transition the buffer to firmware-owned. */
708 	if (rmp_mark_pages_firmware(*desc->paddr_ptr, npages, true)) {
709 		pr_warn("Error moving pages to firmware-owned state for SEV legacy command.\n");
710 		return -EFAULT;
711 	}
712 
713 	return 0;
714 }
715 
snp_unmap_cmd_buf_desc(struct cmd_buf_desc * desc)716 static int snp_unmap_cmd_buf_desc(struct cmd_buf_desc *desc)
717 {
718 	unsigned int npages;
719 
720 	if (!desc->len)
721 		return 0;
722 
723 	npages = PAGE_ALIGN(desc->len) >> PAGE_SHIFT;
724 
725 	/* Transition the buffers back to hypervisor-owned. */
726 	if (snp_reclaim_pages(*desc->paddr_ptr, npages, true)) {
727 		pr_warn("Failed to reclaim firmware-owned pages while issuing SEV legacy command.\n");
728 		return -EFAULT;
729 	}
730 
731 	/* Copy data from bounce buffer and then free it. */
732 	if (!desc->guest_owned) {
733 		void *bounce_buf = __va(__sme_clr(*desc->paddr_ptr));
734 		void *dst_buf = __va(__sme_clr(desc->paddr_orig));
735 
736 		memcpy(dst_buf, bounce_buf, desc->len);
737 		__free_pages(virt_to_page(bounce_buf), get_order(desc->len));
738 
739 		/* Restore the original address in the command buffer. */
740 		*desc->paddr_ptr = desc->paddr_orig;
741 	}
742 
743 	return 0;
744 }
745 
snp_map_cmd_buf_desc_list(int cmd,void * cmd_buf,struct cmd_buf_desc * desc_list)746 static int snp_map_cmd_buf_desc_list(int cmd, void *cmd_buf, struct cmd_buf_desc *desc_list)
747 {
748 	int i;
749 
750 	snp_populate_cmd_buf_desc_list(cmd, cmd_buf, desc_list);
751 
752 	for (i = 0; i < CMD_BUF_DESC_MAX; i++) {
753 		struct cmd_buf_desc *desc = &desc_list[i];
754 
755 		if (!desc->paddr_ptr)
756 			break;
757 
758 		if (snp_map_cmd_buf_desc(desc))
759 			goto err_unmap;
760 	}
761 
762 	return 0;
763 
764 err_unmap:
765 	for (i--; i >= 0; i--)
766 		snp_unmap_cmd_buf_desc(&desc_list[i]);
767 
768 	return -EFAULT;
769 }
770 
snp_unmap_cmd_buf_desc_list(struct cmd_buf_desc * desc_list)771 static int snp_unmap_cmd_buf_desc_list(struct cmd_buf_desc *desc_list)
772 {
773 	int i, ret = 0;
774 
775 	for (i = 0; i < CMD_BUF_DESC_MAX; i++) {
776 		struct cmd_buf_desc *desc = &desc_list[i];
777 
778 		if (!desc->paddr_ptr)
779 			break;
780 
781 		if (snp_unmap_cmd_buf_desc(&desc_list[i]))
782 			ret = -EFAULT;
783 	}
784 
785 	return ret;
786 }
787 
sev_cmd_buf_writable(int cmd)788 static bool sev_cmd_buf_writable(int cmd)
789 {
790 	switch (cmd) {
791 	case SEV_CMD_PLATFORM_STATUS:
792 	case SEV_CMD_GUEST_STATUS:
793 	case SEV_CMD_LAUNCH_START:
794 	case SEV_CMD_RECEIVE_START:
795 	case SEV_CMD_LAUNCH_MEASURE:
796 	case SEV_CMD_SEND_START:
797 	case SEV_CMD_SEND_UPDATE_DATA:
798 	case SEV_CMD_SEND_UPDATE_VMSA:
799 	case SEV_CMD_PEK_CSR:
800 	case SEV_CMD_PDH_CERT_EXPORT:
801 	case SEV_CMD_GET_ID:
802 	case SEV_CMD_ATTESTATION_REPORT:
803 		return true;
804 	default:
805 		return false;
806 	}
807 }
808 
809 /* After SNP is INIT'ed, the behavior of legacy SEV commands is changed. */
snp_legacy_handling_needed(int cmd)810 static bool snp_legacy_handling_needed(int cmd)
811 {
812 	struct sev_device *sev = psp_master->sev_data;
813 
814 	return cmd < SEV_CMD_SNP_INIT && sev->snp_initialized;
815 }
816 
snp_prep_cmd_buf(int cmd,void * cmd_buf,struct cmd_buf_desc * desc_list)817 static int snp_prep_cmd_buf(int cmd, void *cmd_buf, struct cmd_buf_desc *desc_list)
818 {
819 	if (!snp_legacy_handling_needed(cmd))
820 		return 0;
821 
822 	if (snp_map_cmd_buf_desc_list(cmd, cmd_buf, desc_list))
823 		return -EFAULT;
824 
825 	/*
826 	 * Before command execution, the command buffer needs to be put into
827 	 * the firmware-owned state.
828 	 */
829 	if (sev_cmd_buf_writable(cmd)) {
830 		if (rmp_mark_pages_firmware(__pa(cmd_buf), 1, true))
831 			return -EFAULT;
832 	}
833 
834 	return 0;
835 }
836 
snp_reclaim_cmd_buf(int cmd,void * cmd_buf)837 static int snp_reclaim_cmd_buf(int cmd, void *cmd_buf)
838 {
839 	if (!snp_legacy_handling_needed(cmd))
840 		return 0;
841 
842 	/*
843 	 * After command completion, the command buffer needs to be put back
844 	 * into the hypervisor-owned state.
845 	 */
846 	if (sev_cmd_buf_writable(cmd))
847 		if (snp_reclaim_pages(__pa(cmd_buf), 1, true))
848 			return -EFAULT;
849 
850 	return 0;
851 }
852 
__sev_do_cmd_locked(int cmd,void * data,int * psp_ret)853 static int __sev_do_cmd_locked(int cmd, void *data, int *psp_ret)
854 {
855 	struct cmd_buf_desc desc_list[CMD_BUF_DESC_MAX] = {0};
856 	struct psp_device *psp = psp_master;
857 	struct sev_device *sev;
858 	unsigned int cmdbuff_hi, cmdbuff_lo;
859 	unsigned int phys_lsb, phys_msb;
860 	unsigned int reg;
861 	void *cmd_buf;
862 	int buf_len;
863 	int ret = 0;
864 
865 	if (!psp || !psp->sev_data)
866 		return -ENODEV;
867 
868 	if (psp_dead)
869 		return -EBUSY;
870 
871 	sev = psp->sev_data;
872 
873 	buf_len = sev_cmd_buffer_len(cmd);
874 	if (WARN_ON_ONCE(!data != !buf_len))
875 		return -EINVAL;
876 
877 	/*
878 	 * Copy the incoming data to driver's scratch buffer as __pa() will not
879 	 * work for some memory, e.g. vmalloc'd addresses, and @data may not be
880 	 * physically contiguous.
881 	 */
882 	if (data) {
883 		/*
884 		 * Commands are generally issued one at a time and require the
885 		 * sev_cmd_mutex, but there could be recursive firmware requests
886 		 * due to SEV_CMD_SNP_PAGE_RECLAIM needing to be issued while
887 		 * preparing buffers for another command. This is the only known
888 		 * case of nesting in the current code, so exactly one
889 		 * additional command buffer is available for that purpose.
890 		 */
891 		if (!sev->cmd_buf_active) {
892 			cmd_buf = sev->cmd_buf;
893 			sev->cmd_buf_active = true;
894 		} else if (!sev->cmd_buf_backup_active) {
895 			cmd_buf = sev->cmd_buf_backup;
896 			sev->cmd_buf_backup_active = true;
897 		} else {
898 			dev_err(sev->dev,
899 				"SEV: too many firmware commands in progress, no command buffers available.\n");
900 			return -EBUSY;
901 		}
902 
903 		memcpy(cmd_buf, data, buf_len);
904 
905 		/*
906 		 * The behavior of the SEV-legacy commands is altered when the
907 		 * SNP firmware is in the INIT state.
908 		 */
909 		ret = snp_prep_cmd_buf(cmd, cmd_buf, desc_list);
910 		if (ret) {
911 			dev_err(sev->dev,
912 				"SEV: failed to prepare buffer for legacy command 0x%x. Error: %d\n",
913 				cmd, ret);
914 			return ret;
915 		}
916 	} else {
917 		cmd_buf = sev->cmd_buf;
918 	}
919 
920 	/* Get the physical address of the command buffer */
921 	phys_lsb = data ? lower_32_bits(__psp_pa(cmd_buf)) : 0;
922 	phys_msb = data ? upper_32_bits(__psp_pa(cmd_buf)) : 0;
923 
924 	dev_dbg(sev->dev, "sev command id %#x buffer 0x%08x%08x timeout %us\n",
925 		cmd, phys_msb, phys_lsb, psp_timeout);
926 
927 	print_hex_dump_debug("(in):  ", DUMP_PREFIX_OFFSET, 16, 2, data,
928 			     buf_len, false);
929 
930 	iowrite32(phys_lsb, sev->io_regs + sev->vdata->cmdbuff_addr_lo_reg);
931 	iowrite32(phys_msb, sev->io_regs + sev->vdata->cmdbuff_addr_hi_reg);
932 
933 	sev->int_rcvd = 0;
934 
935 	reg = FIELD_PREP(SEV_CMDRESP_CMD, cmd);
936 
937 	/*
938 	 * If invoked during panic handling, local interrupts are disabled so
939 	 * the PSP command completion interrupt can't be used.
940 	 * sev_wait_cmd_ioc() already checks for interrupts disabled and
941 	 * polls for PSP command completion.  Ensure we do not request an
942 	 * interrupt from the PSP if irqs disabled.
943 	 */
944 	if (!irqs_disabled())
945 		reg |= SEV_CMDRESP_IOC;
946 
947 	iowrite32(reg, sev->io_regs + sev->vdata->cmdresp_reg);
948 
949 	/* wait for command completion */
950 	ret = sev_wait_cmd_ioc(sev, &reg, psp_timeout);
951 	if (ret) {
952 		if (psp_ret)
953 			*psp_ret = 0;
954 
955 		dev_err(sev->dev, "sev command %#x timed out, disabling PSP\n", cmd);
956 		psp_dead = true;
957 
958 		return ret;
959 	}
960 
961 	psp_timeout = psp_cmd_timeout;
962 
963 	if (psp_ret)
964 		*psp_ret = FIELD_GET(PSP_CMDRESP_STS, reg);
965 
966 	if (FIELD_GET(PSP_CMDRESP_STS, reg)) {
967 		dev_dbg(sev->dev, "sev command %#x failed (%#010lx)\n",
968 			cmd, FIELD_GET(PSP_CMDRESP_STS, reg));
969 
970 		/*
971 		 * PSP firmware may report additional error information in the
972 		 * command buffer registers on error. Print contents of command
973 		 * buffer registers if they changed.
974 		 */
975 		cmdbuff_hi = ioread32(sev->io_regs + sev->vdata->cmdbuff_addr_hi_reg);
976 		cmdbuff_lo = ioread32(sev->io_regs + sev->vdata->cmdbuff_addr_lo_reg);
977 		if (cmdbuff_hi != phys_msb || cmdbuff_lo != phys_lsb) {
978 			dev_dbg(sev->dev, "Additional error information reported in cmdbuff:");
979 			dev_dbg(sev->dev, "  cmdbuff hi: %#010x\n", cmdbuff_hi);
980 			dev_dbg(sev->dev, "  cmdbuff lo: %#010x\n", cmdbuff_lo);
981 		}
982 		ret = -EIO;
983 	} else {
984 		ret = sev_write_init_ex_file_if_required(cmd);
985 	}
986 
987 	/*
988 	 * Copy potential output from the PSP back to data.  Do this even on
989 	 * failure in case the caller wants to glean something from the error.
990 	 */
991 	if (data) {
992 		int ret_reclaim;
993 		/*
994 		 * Restore the page state after the command completes.
995 		 */
996 		ret_reclaim = snp_reclaim_cmd_buf(cmd, cmd_buf);
997 		if (ret_reclaim) {
998 			dev_err(sev->dev,
999 				"SEV: failed to reclaim buffer for legacy command %#x. Error: %d\n",
1000 				cmd, ret_reclaim);
1001 			return ret_reclaim;
1002 		}
1003 
1004 		memcpy(data, cmd_buf, buf_len);
1005 
1006 		if (sev->cmd_buf_backup_active)
1007 			sev->cmd_buf_backup_active = false;
1008 		else
1009 			sev->cmd_buf_active = false;
1010 
1011 		if (snp_unmap_cmd_buf_desc_list(desc_list))
1012 			return -EFAULT;
1013 	}
1014 
1015 	print_hex_dump_debug("(out): ", DUMP_PREFIX_OFFSET, 16, 2, data,
1016 			     buf_len, false);
1017 
1018 	return ret;
1019 }
1020 
sev_do_cmd(int cmd,void * data,int * psp_ret)1021 int sev_do_cmd(int cmd, void *data, int *psp_ret)
1022 {
1023 	int rc;
1024 
1025 	mutex_lock(&sev_cmd_mutex);
1026 	rc = __sev_do_cmd_locked(cmd, data, psp_ret);
1027 	mutex_unlock(&sev_cmd_mutex);
1028 
1029 	return rc;
1030 }
1031 EXPORT_SYMBOL_GPL(sev_do_cmd);
1032 
__sev_init_locked(int * error)1033 static int __sev_init_locked(int *error)
1034 {
1035 	struct sev_data_init data;
1036 
1037 	memset(&data, 0, sizeof(data));
1038 	if (sev_es_tmr) {
1039 		/*
1040 		 * Do not include the encryption mask on the physical
1041 		 * address of the TMR (firmware should clear it anyway).
1042 		 */
1043 		data.tmr_address = __pa(sev_es_tmr);
1044 
1045 		data.flags |= SEV_INIT_FLAGS_SEV_ES;
1046 		data.tmr_len = sev_es_tmr_size;
1047 	}
1048 
1049 	return __sev_do_cmd_locked(SEV_CMD_INIT, &data, error);
1050 }
1051 
__sev_init_ex_locked(int * error)1052 static int __sev_init_ex_locked(int *error)
1053 {
1054 	struct sev_data_init_ex data;
1055 
1056 	memset(&data, 0, sizeof(data));
1057 	data.length = sizeof(data);
1058 	data.nv_address = __psp_pa(sev_init_ex_buffer);
1059 	data.nv_len = NV_LENGTH;
1060 
1061 	if (sev_es_tmr) {
1062 		/*
1063 		 * Do not include the encryption mask on the physical
1064 		 * address of the TMR (firmware should clear it anyway).
1065 		 */
1066 		data.tmr_address = __pa(sev_es_tmr);
1067 
1068 		data.flags |= SEV_INIT_FLAGS_SEV_ES;
1069 		data.tmr_len = sev_es_tmr_size;
1070 	}
1071 
1072 	return __sev_do_cmd_locked(SEV_CMD_INIT_EX, &data, error);
1073 }
1074 
__sev_do_init_locked(int * psp_ret)1075 static inline int __sev_do_init_locked(int *psp_ret)
1076 {
1077 	if (sev_init_ex_buffer)
1078 		return __sev_init_ex_locked(psp_ret);
1079 	else
1080 		return __sev_init_locked(psp_ret);
1081 }
1082 
snp_set_hsave_pa(void * arg)1083 static void snp_set_hsave_pa(void *arg)
1084 {
1085 	wrmsrq(MSR_VM_HSAVE_PA, 0);
1086 }
1087 
1088 /* Hypervisor Fixed pages API interface */
snp_hv_fixed_pages_state_update(struct sev_device * sev,enum snp_hv_fixed_pages_state page_state)1089 static void snp_hv_fixed_pages_state_update(struct sev_device *sev,
1090 					    enum snp_hv_fixed_pages_state page_state)
1091 {
1092 	struct snp_hv_fixed_pages_entry *entry;
1093 
1094 	/* List is protected by sev_cmd_mutex */
1095 	lockdep_assert_held(&sev_cmd_mutex);
1096 
1097 	if (list_empty(&snp_hv_fixed_pages))
1098 		return;
1099 
1100 	list_for_each_entry(entry, &snp_hv_fixed_pages, list)
1101 		entry->page_state = page_state;
1102 }
1103 
1104 /*
1105  * Allocate HV_FIXED pages in 2MB aligned sizes to ensure the whole
1106  * 2MB pages are marked as HV_FIXED.
1107  */
snp_alloc_hv_fixed_pages(unsigned int num_2mb_pages)1108 struct page *snp_alloc_hv_fixed_pages(unsigned int num_2mb_pages)
1109 {
1110 	struct psp_device *psp_master = psp_get_master_device();
1111 	struct snp_hv_fixed_pages_entry *entry;
1112 	struct sev_device *sev;
1113 	unsigned int order;
1114 	struct page *page;
1115 
1116 	if (!psp_master || !psp_master->sev_data)
1117 		return NULL;
1118 
1119 	sev = psp_master->sev_data;
1120 
1121 	order = get_order(PMD_SIZE * num_2mb_pages);
1122 
1123 	/*
1124 	 * SNP_INIT_EX is protected by sev_cmd_mutex, therefore this list
1125 	 * also needs to be protected using the same mutex.
1126 	 */
1127 	guard(mutex)(&sev_cmd_mutex);
1128 
1129 	/*
1130 	 * This API uses SNP_INIT_EX to transition allocated pages to HV_Fixed
1131 	 * page state, fail if SNP is already initialized.
1132 	 */
1133 	if (sev->snp_initialized)
1134 		return NULL;
1135 
1136 	/* Re-use freed pages that match the request */
1137 	list_for_each_entry(entry, &snp_hv_fixed_pages, list) {
1138 		/* Hypervisor fixed page allocator implements exact fit policy */
1139 		if (entry->order == order && entry->free) {
1140 			entry->free = false;
1141 			memset(page_address(entry->page), 0,
1142 			       (1 << entry->order) * PAGE_SIZE);
1143 			return entry->page;
1144 		}
1145 	}
1146 
1147 	page = alloc_pages(GFP_KERNEL | __GFP_ZERO, order);
1148 	if (!page)
1149 		return NULL;
1150 
1151 	entry = kzalloc(sizeof(*entry), GFP_KERNEL);
1152 	if (!entry) {
1153 		__free_pages(page, order);
1154 		return NULL;
1155 	}
1156 
1157 	entry->page = page;
1158 	entry->order = order;
1159 	list_add_tail(&entry->list, &snp_hv_fixed_pages);
1160 
1161 	return page;
1162 }
1163 
snp_free_hv_fixed_pages(struct page * page)1164 void snp_free_hv_fixed_pages(struct page *page)
1165 {
1166 	struct psp_device *psp_master = psp_get_master_device();
1167 	struct snp_hv_fixed_pages_entry *entry, *nentry;
1168 
1169 	if (!psp_master || !psp_master->sev_data)
1170 		return;
1171 
1172 	/*
1173 	 * SNP_INIT_EX is protected by sev_cmd_mutex, therefore this list
1174 	 * also needs to be protected using the same mutex.
1175 	 */
1176 	guard(mutex)(&sev_cmd_mutex);
1177 
1178 	list_for_each_entry_safe(entry, nentry, &snp_hv_fixed_pages, list) {
1179 		if (entry->page != page)
1180 			continue;
1181 
1182 		/*
1183 		 * HV_FIXED page state cannot be changed until reboot
1184 		 * and they cannot be used by an SNP guest, so they cannot
1185 		 * be returned back to the page allocator.
1186 		 * Mark the pages as free internally to allow possible re-use.
1187 		 */
1188 		if (entry->page_state == HV_FIXED) {
1189 			entry->free = true;
1190 		} else {
1191 			__free_pages(page, entry->order);
1192 			list_del(&entry->list);
1193 			kfree(entry);
1194 		}
1195 		return;
1196 	}
1197 }
1198 
snp_add_hv_fixed_pages(struct sev_device * sev,struct sev_data_range_list * range_list)1199 static void snp_add_hv_fixed_pages(struct sev_device *sev, struct sev_data_range_list *range_list)
1200 {
1201 	struct snp_hv_fixed_pages_entry *entry;
1202 	struct sev_data_range *range;
1203 	int num_elements;
1204 
1205 	lockdep_assert_held(&sev_cmd_mutex);
1206 
1207 	if (list_empty(&snp_hv_fixed_pages))
1208 		return;
1209 
1210 	num_elements = list_count_nodes(&snp_hv_fixed_pages) +
1211 		       range_list->num_elements;
1212 
1213 	/*
1214 	 * Ensure the list of HV_FIXED pages that will be passed to firmware
1215 	 * do not exceed the page-sized argument buffer.
1216 	 */
1217 	if (num_elements * sizeof(*range) + sizeof(*range_list) > PAGE_SIZE) {
1218 		dev_warn(sev->dev, "Additional HV_Fixed pages cannot be accommodated, omitting\n");
1219 		return;
1220 	}
1221 
1222 	range = &range_list->ranges[range_list->num_elements];
1223 	list_for_each_entry(entry, &snp_hv_fixed_pages, list) {
1224 		range->base = page_to_pfn(entry->page) << PAGE_SHIFT;
1225 		range->page_count = 1 << entry->order;
1226 		range++;
1227 	}
1228 	range_list->num_elements = num_elements;
1229 }
1230 
snp_leak_hv_fixed_pages(void)1231 static void snp_leak_hv_fixed_pages(void)
1232 {
1233 	struct snp_hv_fixed_pages_entry *entry;
1234 
1235 	/* List is protected by sev_cmd_mutex */
1236 	lockdep_assert_held(&sev_cmd_mutex);
1237 
1238 	if (list_empty(&snp_hv_fixed_pages))
1239 		return;
1240 
1241 	list_for_each_entry(entry, &snp_hv_fixed_pages, list)
1242 		if (entry->page_state == HV_FIXED)
1243 			__snp_leak_pages(page_to_pfn(entry->page),
1244 					 1 << entry->order, false);
1245 }
1246 
sev_is_snp_ciphertext_hiding_supported(void)1247 bool sev_is_snp_ciphertext_hiding_supported(void)
1248 {
1249 	struct psp_device *psp = psp_master;
1250 	struct sev_device *sev;
1251 
1252 	if (!psp || !psp->sev_data)
1253 		return false;
1254 
1255 	sev = psp->sev_data;
1256 
1257 	/*
1258 	 * Feature information indicates if CipherTextHiding feature is
1259 	 * supported by the SEV firmware and additionally platform status
1260 	 * indicates if CipherTextHiding feature is enabled in the
1261 	 * Platform BIOS.
1262 	 */
1263 	return ((sev->snp_feat_info_0.ecx & SNP_CIPHER_TEXT_HIDING_SUPPORTED) &&
1264 		 sev->snp_plat_status.ciphertext_hiding_cap);
1265 }
1266 EXPORT_SYMBOL_GPL(sev_is_snp_ciphertext_hiding_supported);
1267 
snp_get_platform_data(struct sev_device * sev,int * error)1268 static int snp_get_platform_data(struct sev_device *sev, int *error)
1269 {
1270 	struct sev_data_snp_feature_info snp_feat_info;
1271 	struct snp_feature_info *feat_info;
1272 	struct sev_data_snp_addr buf;
1273 	struct page *page;
1274 	int rc;
1275 
1276 	/*
1277 	 * This function is expected to be called before SNP is
1278 	 * initialized.
1279 	 */
1280 	if (sev->snp_initialized)
1281 		return -EINVAL;
1282 
1283 	buf.address = __psp_pa(&sev->snp_plat_status);
1284 	rc = sev_do_cmd(SEV_CMD_SNP_PLATFORM_STATUS, &buf, error);
1285 	if (rc) {
1286 		dev_err(sev->dev, "SNP PLATFORM_STATUS command failed, ret = %d, error = %#x\n",
1287 			rc, *error);
1288 		return rc;
1289 	}
1290 
1291 	sev->api_major = sev->snp_plat_status.api_major;
1292 	sev->api_minor = sev->snp_plat_status.api_minor;
1293 	sev->build = sev->snp_plat_status.build_id;
1294 
1295 	/*
1296 	 * Do feature discovery of the currently loaded firmware,
1297 	 * and cache feature information from CPUID 0x8000_0024,
1298 	 * sub-function 0.
1299 	 */
1300 	if (!sev->snp_plat_status.feature_info)
1301 		return 0;
1302 
1303 	/*
1304 	 * Use dynamically allocated structure for the SNP_FEATURE_INFO
1305 	 * command to ensure structure is 8-byte aligned, and does not
1306 	 * cross a page boundary.
1307 	 */
1308 	page = alloc_page(GFP_KERNEL);
1309 	if (!page)
1310 		return -ENOMEM;
1311 
1312 	feat_info = page_address(page);
1313 	snp_feat_info.length = sizeof(snp_feat_info);
1314 	snp_feat_info.ecx_in = 0;
1315 	snp_feat_info.feature_info_paddr = __psp_pa(feat_info);
1316 
1317 	rc = sev_do_cmd(SEV_CMD_SNP_FEATURE_INFO, &snp_feat_info, error);
1318 	if (!rc)
1319 		sev->snp_feat_info_0 = *feat_info;
1320 	else
1321 		dev_err(sev->dev, "SNP FEATURE_INFO command failed, ret = %d, error = %#x\n",
1322 			rc, *error);
1323 
1324 	__free_page(page);
1325 
1326 	return rc;
1327 }
1328 
snp_filter_reserved_mem_regions(struct resource * rs,void * arg)1329 static int snp_filter_reserved_mem_regions(struct resource *rs, void *arg)
1330 {
1331 	struct sev_data_range_list *range_list = arg;
1332 	struct sev_data_range *range = &range_list->ranges[range_list->num_elements];
1333 	size_t size;
1334 
1335 	/*
1336 	 * Ensure the list of HV_FIXED pages that will be passed to firmware
1337 	 * do not exceed the page-sized argument buffer.
1338 	 */
1339 	if ((range_list->num_elements * sizeof(struct sev_data_range) +
1340 	     sizeof(struct sev_data_range_list)) > PAGE_SIZE)
1341 		return -E2BIG;
1342 
1343 	switch (rs->desc) {
1344 	case E820_TYPE_RESERVED:
1345 	case E820_TYPE_PMEM:
1346 	case E820_TYPE_ACPI:
1347 		range->base = rs->start & PAGE_MASK;
1348 		size = PAGE_ALIGN((rs->end + 1) - rs->start);
1349 		range->page_count = size >> PAGE_SHIFT;
1350 		range_list->num_elements++;
1351 		break;
1352 	default:
1353 		break;
1354 	}
1355 
1356 	return 0;
1357 }
1358 
__sev_snp_init_locked(int * error,unsigned int max_snp_asid)1359 static int __sev_snp_init_locked(int *error, unsigned int max_snp_asid)
1360 {
1361 	struct psp_device *psp = psp_master;
1362 	struct sev_data_snp_init_ex data;
1363 	struct sev_device *sev;
1364 	void *arg = &data;
1365 	int cmd, rc = 0;
1366 
1367 	if (!cc_platform_has(CC_ATTR_HOST_SEV_SNP))
1368 		return -ENODEV;
1369 
1370 	sev = psp->sev_data;
1371 
1372 	if (sev->snp_initialized)
1373 		return 0;
1374 
1375 	if (!sev_version_greater_or_equal(SNP_MIN_API_MAJOR, SNP_MIN_API_MINOR)) {
1376 		dev_dbg(sev->dev, "SEV-SNP support requires firmware version >= %d:%d\n",
1377 			SNP_MIN_API_MAJOR, SNP_MIN_API_MINOR);
1378 		return -EOPNOTSUPP;
1379 	}
1380 
1381 	/* SNP_INIT requires MSR_VM_HSAVE_PA to be cleared on all CPUs. */
1382 	on_each_cpu(snp_set_hsave_pa, NULL, 1);
1383 
1384 	/*
1385 	 * Starting in SNP firmware v1.52, the SNP_INIT_EX command takes a list
1386 	 * of system physical address ranges to convert into HV-fixed page
1387 	 * states during the RMP initialization.  For instance, the memory that
1388 	 * UEFI reserves should be included in the that list. This allows system
1389 	 * components that occasionally write to memory (e.g. logging to UEFI
1390 	 * reserved regions) to not fail due to RMP initialization and SNP
1391 	 * enablement.
1392 	 *
1393 	 */
1394 	if (sev_version_greater_or_equal(SNP_MIN_API_MAJOR, 52)) {
1395 		/*
1396 		 * Firmware checks that the pages containing the ranges enumerated
1397 		 * in the RANGES structure are either in the default page state or in the
1398 		 * firmware page state.
1399 		 */
1400 		snp_range_list = kzalloc(PAGE_SIZE, GFP_KERNEL);
1401 		if (!snp_range_list) {
1402 			dev_err(sev->dev,
1403 				"SEV: SNP_INIT_EX range list memory allocation failed\n");
1404 			return -ENOMEM;
1405 		}
1406 
1407 		/*
1408 		 * Retrieve all reserved memory regions from the e820 memory map
1409 		 * to be setup as HV-fixed pages.
1410 		 */
1411 		rc = walk_iomem_res_desc(IORES_DESC_NONE, IORESOURCE_MEM, 0, ~0,
1412 					 snp_range_list, snp_filter_reserved_mem_regions);
1413 		if (rc) {
1414 			dev_err(sev->dev,
1415 				"SEV: SNP_INIT_EX walk_iomem_res_desc failed rc = %d\n", rc);
1416 			return rc;
1417 		}
1418 
1419 		/*
1420 		 * Add HV_Fixed pages from other PSP sub-devices, such as SFS to the
1421 		 * HV_Fixed page list.
1422 		 */
1423 		snp_add_hv_fixed_pages(sev, snp_range_list);
1424 
1425 		memset(&data, 0, sizeof(data));
1426 
1427 		if (max_snp_asid) {
1428 			data.ciphertext_hiding_en = 1;
1429 			data.max_snp_asid = max_snp_asid;
1430 		}
1431 
1432 		data.init_rmp = 1;
1433 		data.list_paddr_en = 1;
1434 		data.list_paddr = __psp_pa(snp_range_list);
1435 		cmd = SEV_CMD_SNP_INIT_EX;
1436 	} else {
1437 		cmd = SEV_CMD_SNP_INIT;
1438 		arg = NULL;
1439 	}
1440 
1441 	/*
1442 	 * The following sequence must be issued before launching the first SNP
1443 	 * guest to ensure all dirty cache lines are flushed, including from
1444 	 * updates to the RMP table itself via the RMPUPDATE instruction:
1445 	 *
1446 	 * - WBINVD on all running CPUs
1447 	 * - SEV_CMD_SNP_INIT[_EX] firmware command
1448 	 * - WBINVD on all running CPUs
1449 	 * - SEV_CMD_SNP_DF_FLUSH firmware command
1450 	 */
1451 	wbinvd_on_all_cpus();
1452 
1453 	rc = __sev_do_cmd_locked(cmd, arg, error);
1454 	if (rc) {
1455 		dev_err(sev->dev, "SEV-SNP: %s failed rc %d, error %#x\n",
1456 			cmd == SEV_CMD_SNP_INIT_EX ? "SNP_INIT_EX" : "SNP_INIT",
1457 			rc, *error);
1458 		return rc;
1459 	}
1460 
1461 	/* Prepare for first SNP guest launch after INIT. */
1462 	wbinvd_on_all_cpus();
1463 	rc = __sev_do_cmd_locked(SEV_CMD_SNP_DF_FLUSH, NULL, error);
1464 	if (rc) {
1465 		dev_err(sev->dev, "SEV-SNP: SNP_DF_FLUSH failed rc %d, error %#x\n",
1466 			rc, *error);
1467 		return rc;
1468 	}
1469 
1470 	snp_hv_fixed_pages_state_update(sev, HV_FIXED);
1471 	sev->snp_initialized = true;
1472 	dev_dbg(sev->dev, "SEV-SNP firmware initialized\n");
1473 
1474 	dev_info(sev->dev, "SEV-SNP API:%d.%d build:%d\n", sev->api_major,
1475 		 sev->api_minor, sev->build);
1476 
1477 	atomic_notifier_chain_register(&panic_notifier_list,
1478 				       &snp_panic_notifier);
1479 
1480 	sev_es_tmr_size = SNP_TMR_SIZE;
1481 
1482 	return 0;
1483 }
1484 
__sev_platform_init_handle_tmr(struct sev_device * sev)1485 static void __sev_platform_init_handle_tmr(struct sev_device *sev)
1486 {
1487 	if (sev_es_tmr)
1488 		return;
1489 
1490 	/* Obtain the TMR memory area for SEV-ES use */
1491 	sev_es_tmr = sev_fw_alloc(sev_es_tmr_size);
1492 	if (sev_es_tmr) {
1493 		/* Must flush the cache before giving it to the firmware */
1494 		if (!sev->snp_initialized)
1495 			clflush_cache_range(sev_es_tmr, sev_es_tmr_size);
1496 	} else {
1497 			dev_warn(sev->dev, "SEV: TMR allocation failed, SEV-ES support unavailable\n");
1498 	}
1499 }
1500 
1501 /*
1502  * If an init_ex_path is provided allocate a buffer for the file and
1503  * read in the contents. Additionally, if SNP is initialized, convert
1504  * the buffer pages to firmware pages.
1505  */
__sev_platform_init_handle_init_ex_path(struct sev_device * sev)1506 static int __sev_platform_init_handle_init_ex_path(struct sev_device *sev)
1507 {
1508 	struct page *page;
1509 	int rc;
1510 
1511 	if (!init_ex_path)
1512 		return 0;
1513 
1514 	if (sev_init_ex_buffer)
1515 		return 0;
1516 
1517 	page = alloc_pages(GFP_KERNEL, get_order(NV_LENGTH));
1518 	if (!page) {
1519 		dev_err(sev->dev, "SEV: INIT_EX NV memory allocation failed\n");
1520 		return -ENOMEM;
1521 	}
1522 
1523 	sev_init_ex_buffer = page_address(page);
1524 
1525 	rc = sev_read_init_ex_file();
1526 	if (rc)
1527 		return rc;
1528 
1529 	/* If SEV-SNP is initialized, transition to firmware page. */
1530 	if (sev->snp_initialized) {
1531 		unsigned long npages;
1532 
1533 		npages = 1UL << get_order(NV_LENGTH);
1534 		if (rmp_mark_pages_firmware(__pa(sev_init_ex_buffer), npages, false)) {
1535 			dev_err(sev->dev, "SEV: INIT_EX NV memory page state change failed.\n");
1536 			return -ENOMEM;
1537 		}
1538 	}
1539 
1540 	return 0;
1541 }
1542 
__sev_platform_init_locked(int * error)1543 static int __sev_platform_init_locked(int *error)
1544 {
1545 	int rc, psp_ret, dfflush_error;
1546 	struct sev_device *sev;
1547 
1548 	psp_ret = dfflush_error = SEV_RET_NO_FW_CALL;
1549 
1550 	if (!psp_master || !psp_master->sev_data)
1551 		return -ENODEV;
1552 
1553 	sev = psp_master->sev_data;
1554 
1555 	if (sev->sev_plat_status.state == SEV_STATE_INIT)
1556 		return 0;
1557 
1558 	__sev_platform_init_handle_tmr(sev);
1559 
1560 	rc = __sev_platform_init_handle_init_ex_path(sev);
1561 	if (rc)
1562 		return rc;
1563 
1564 	rc = __sev_do_init_locked(&psp_ret);
1565 	if (rc && psp_ret == SEV_RET_SECURE_DATA_INVALID) {
1566 		/*
1567 		 * Initialization command returned an integrity check failure
1568 		 * status code, meaning that firmware load and validation of SEV
1569 		 * related persistent data has failed. Retrying the
1570 		 * initialization function should succeed by replacing the state
1571 		 * with a reset state.
1572 		 */
1573 		dev_err(sev->dev,
1574 "SEV: retrying INIT command because of SECURE_DATA_INVALID error. Retrying once to reset PSP SEV state.");
1575 		rc = __sev_do_init_locked(&psp_ret);
1576 	}
1577 
1578 	if (error)
1579 		*error = psp_ret;
1580 
1581 	if (rc) {
1582 		dev_err(sev->dev, "SEV: %s failed %#x, rc %d\n",
1583 			sev_init_ex_buffer ? "INIT_EX" : "INIT", psp_ret, rc);
1584 		return rc;
1585 	}
1586 
1587 	sev->sev_plat_status.state = SEV_STATE_INIT;
1588 
1589 	/* Prepare for first SEV guest launch after INIT */
1590 	wbinvd_on_all_cpus();
1591 	rc = __sev_do_cmd_locked(SEV_CMD_DF_FLUSH, NULL, &dfflush_error);
1592 	if (rc) {
1593 		dev_err(sev->dev, "SEV: DF_FLUSH failed %#x, rc %d\n",
1594 			dfflush_error, rc);
1595 		return rc;
1596 	}
1597 
1598 	dev_dbg(sev->dev, "SEV firmware initialized\n");
1599 
1600 	dev_info(sev->dev, "SEV API:%d.%d build:%d\n", sev->api_major,
1601 		 sev->api_minor, sev->build);
1602 
1603 	return 0;
1604 }
1605 
_sev_platform_init_locked(struct sev_platform_init_args * args)1606 static int _sev_platform_init_locked(struct sev_platform_init_args *args)
1607 {
1608 	struct sev_device *sev;
1609 	int rc;
1610 
1611 	if (!psp_master || !psp_master->sev_data)
1612 		return -ENODEV;
1613 
1614 	/*
1615 	 * Skip SNP/SEV initialization under a kdump kernel as SEV/SNP
1616 	 * may already be initialized in the previous kernel. Since no
1617 	 * SNP/SEV guests are run under a kdump kernel, there is no
1618 	 * need to initialize SNP or SEV during kdump boot.
1619 	 */
1620 	if (is_kdump_kernel())
1621 		return 0;
1622 
1623 	sev = psp_master->sev_data;
1624 
1625 	if (sev->sev_plat_status.state == SEV_STATE_INIT)
1626 		return 0;
1627 
1628 	rc = __sev_snp_init_locked(&args->error, args->max_snp_asid);
1629 	if (rc && rc != -ENODEV)
1630 		return rc;
1631 
1632 	/* Defer legacy SEV/SEV-ES support if allowed by caller/module. */
1633 	if (args->probe && !psp_init_on_probe)
1634 		return 0;
1635 
1636 	return __sev_platform_init_locked(&args->error);
1637 }
1638 
sev_platform_init(struct sev_platform_init_args * args)1639 int sev_platform_init(struct sev_platform_init_args *args)
1640 {
1641 	int rc;
1642 
1643 	mutex_lock(&sev_cmd_mutex);
1644 	rc = _sev_platform_init_locked(args);
1645 	mutex_unlock(&sev_cmd_mutex);
1646 
1647 	return rc;
1648 }
1649 EXPORT_SYMBOL_GPL(sev_platform_init);
1650 
__sev_platform_shutdown_locked(int * error)1651 static int __sev_platform_shutdown_locked(int *error)
1652 {
1653 	struct psp_device *psp = psp_master;
1654 	struct sev_device *sev;
1655 	int ret;
1656 
1657 	if (!psp || !psp->sev_data)
1658 		return 0;
1659 
1660 	sev = psp->sev_data;
1661 
1662 	if (sev->sev_plat_status.state == SEV_STATE_UNINIT)
1663 		return 0;
1664 
1665 	ret = __sev_do_cmd_locked(SEV_CMD_SHUTDOWN, NULL, error);
1666 	if (ret) {
1667 		dev_err(sev->dev, "SEV: failed to SHUTDOWN error %#x, rc %d\n",
1668 			*error, ret);
1669 		return ret;
1670 	}
1671 
1672 	sev->sev_plat_status.state = SEV_STATE_UNINIT;
1673 	dev_dbg(sev->dev, "SEV firmware shutdown\n");
1674 
1675 	return ret;
1676 }
1677 
sev_get_platform_state(int * state,int * error)1678 static int sev_get_platform_state(int *state, int *error)
1679 {
1680 	struct sev_user_data_status data;
1681 	int rc;
1682 
1683 	rc = __sev_do_cmd_locked(SEV_CMD_PLATFORM_STATUS, &data, error);
1684 	if (rc)
1685 		return rc;
1686 
1687 	*state = data.state;
1688 	return rc;
1689 }
1690 
sev_move_to_init_state(struct sev_issue_cmd * argp,bool * shutdown_required)1691 static int sev_move_to_init_state(struct sev_issue_cmd *argp, bool *shutdown_required)
1692 {
1693 	struct sev_platform_init_args init_args = {0};
1694 	int rc;
1695 
1696 	rc = _sev_platform_init_locked(&init_args);
1697 	if (rc) {
1698 		argp->error = SEV_RET_INVALID_PLATFORM_STATE;
1699 		return rc;
1700 	}
1701 
1702 	*shutdown_required = true;
1703 
1704 	return 0;
1705 }
1706 
snp_move_to_init_state(struct sev_issue_cmd * argp,bool * shutdown_required)1707 static int snp_move_to_init_state(struct sev_issue_cmd *argp, bool *shutdown_required)
1708 {
1709 	int error, rc;
1710 
1711 	rc = __sev_snp_init_locked(&error, 0);
1712 	if (rc) {
1713 		argp->error = SEV_RET_INVALID_PLATFORM_STATE;
1714 		return rc;
1715 	}
1716 
1717 	*shutdown_required = true;
1718 
1719 	return 0;
1720 }
1721 
sev_ioctl_do_reset(struct sev_issue_cmd * argp,bool writable)1722 static int sev_ioctl_do_reset(struct sev_issue_cmd *argp, bool writable)
1723 {
1724 	int state, rc;
1725 
1726 	if (!writable)
1727 		return -EPERM;
1728 
1729 	/*
1730 	 * The SEV spec requires that FACTORY_RESET must be issued in
1731 	 * UNINIT state. Before we go further lets check if any guest is
1732 	 * active.
1733 	 *
1734 	 * If FW is in WORKING state then deny the request otherwise issue
1735 	 * SHUTDOWN command do INIT -> UNINIT before issuing the FACTORY_RESET.
1736 	 *
1737 	 */
1738 	rc = sev_get_platform_state(&state, &argp->error);
1739 	if (rc)
1740 		return rc;
1741 
1742 	if (state == SEV_STATE_WORKING)
1743 		return -EBUSY;
1744 
1745 	if (state == SEV_STATE_INIT) {
1746 		rc = __sev_platform_shutdown_locked(&argp->error);
1747 		if (rc)
1748 			return rc;
1749 	}
1750 
1751 	return __sev_do_cmd_locked(SEV_CMD_FACTORY_RESET, NULL, &argp->error);
1752 }
1753 
sev_ioctl_do_platform_status(struct sev_issue_cmd * argp)1754 static int sev_ioctl_do_platform_status(struct sev_issue_cmd *argp)
1755 {
1756 	struct sev_user_data_status data;
1757 	int ret;
1758 
1759 	memset(&data, 0, sizeof(data));
1760 
1761 	ret = __sev_do_cmd_locked(SEV_CMD_PLATFORM_STATUS, &data, &argp->error);
1762 	if (ret)
1763 		return ret;
1764 
1765 	if (copy_to_user((void __user *)argp->data, &data, sizeof(data)))
1766 		ret = -EFAULT;
1767 
1768 	return ret;
1769 }
1770 
sev_ioctl_do_pek_pdh_gen(int cmd,struct sev_issue_cmd * argp,bool writable)1771 static int sev_ioctl_do_pek_pdh_gen(int cmd, struct sev_issue_cmd *argp, bool writable)
1772 {
1773 	struct sev_device *sev = psp_master->sev_data;
1774 	bool shutdown_required = false;
1775 	int rc;
1776 
1777 	if (!writable)
1778 		return -EPERM;
1779 
1780 	if (sev->sev_plat_status.state == SEV_STATE_UNINIT) {
1781 		rc = sev_move_to_init_state(argp, &shutdown_required);
1782 		if (rc)
1783 			return rc;
1784 	}
1785 
1786 	rc = __sev_do_cmd_locked(cmd, NULL, &argp->error);
1787 
1788 	if (shutdown_required)
1789 		__sev_firmware_shutdown(sev, false);
1790 
1791 	return rc;
1792 }
1793 
sev_ioctl_do_pek_csr(struct sev_issue_cmd * argp,bool writable)1794 static int sev_ioctl_do_pek_csr(struct sev_issue_cmd *argp, bool writable)
1795 {
1796 	struct sev_device *sev = psp_master->sev_data;
1797 	struct sev_user_data_pek_csr input;
1798 	bool shutdown_required = false;
1799 	struct sev_data_pek_csr data;
1800 	void __user *input_address;
1801 	void *blob = NULL;
1802 	int ret;
1803 
1804 	if (!writable)
1805 		return -EPERM;
1806 
1807 	if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
1808 		return -EFAULT;
1809 
1810 	memset(&data, 0, sizeof(data));
1811 
1812 	/* userspace wants to query CSR length */
1813 	if (!input.address || !input.length)
1814 		goto cmd;
1815 
1816 	/* allocate a physically contiguous buffer to store the CSR blob */
1817 	input_address = (void __user *)input.address;
1818 	if (input.length > SEV_FW_BLOB_MAX_SIZE)
1819 		return -EFAULT;
1820 
1821 	blob = kzalloc(input.length, GFP_KERNEL);
1822 	if (!blob)
1823 		return -ENOMEM;
1824 
1825 	data.address = __psp_pa(blob);
1826 	data.len = input.length;
1827 
1828 cmd:
1829 	if (sev->sev_plat_status.state == SEV_STATE_UNINIT) {
1830 		ret = sev_move_to_init_state(argp, &shutdown_required);
1831 		if (ret)
1832 			goto e_free_blob;
1833 	}
1834 
1835 	ret = __sev_do_cmd_locked(SEV_CMD_PEK_CSR, &data, &argp->error);
1836 
1837 	 /* If we query the CSR length, FW responded with expected data. */
1838 	input.length = data.len;
1839 
1840 	if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) {
1841 		ret = -EFAULT;
1842 		goto e_free_blob;
1843 	}
1844 
1845 	if (blob) {
1846 		if (copy_to_user(input_address, blob, input.length))
1847 			ret = -EFAULT;
1848 	}
1849 
1850 e_free_blob:
1851 	if (shutdown_required)
1852 		__sev_firmware_shutdown(sev, false);
1853 
1854 	kfree(blob);
1855 	return ret;
1856 }
1857 
psp_copy_user_blob(u64 uaddr,u32 len)1858 void *psp_copy_user_blob(u64 uaddr, u32 len)
1859 {
1860 	if (!uaddr || !len)
1861 		return ERR_PTR(-EINVAL);
1862 
1863 	/* verify that blob length does not exceed our limit */
1864 	if (len > SEV_FW_BLOB_MAX_SIZE)
1865 		return ERR_PTR(-EINVAL);
1866 
1867 	return memdup_user((void __user *)uaddr, len);
1868 }
1869 EXPORT_SYMBOL_GPL(psp_copy_user_blob);
1870 
sev_get_api_version(void)1871 static int sev_get_api_version(void)
1872 {
1873 	struct sev_device *sev = psp_master->sev_data;
1874 	struct sev_user_data_status status;
1875 	int error = 0, ret;
1876 
1877 	/*
1878 	 * Cache SNP platform status and SNP feature information
1879 	 * if SNP is available.
1880 	 */
1881 	if (cc_platform_has(CC_ATTR_HOST_SEV_SNP)) {
1882 		ret = snp_get_platform_data(sev, &error);
1883 		if (ret)
1884 			return 1;
1885 	}
1886 
1887 	ret = sev_platform_status(&status, &error);
1888 	if (ret) {
1889 		dev_err(sev->dev,
1890 			"SEV: failed to get status. Error: %#x\n", error);
1891 		return 1;
1892 	}
1893 
1894 	/* Cache SEV platform status */
1895 	sev->sev_plat_status = status;
1896 
1897 	sev->api_major = status.api_major;
1898 	sev->api_minor = status.api_minor;
1899 	sev->build = status.build;
1900 
1901 	return 0;
1902 }
1903 
sev_get_firmware(struct device * dev,const struct firmware ** firmware)1904 static int sev_get_firmware(struct device *dev,
1905 			    const struct firmware **firmware)
1906 {
1907 	char fw_name_specific[SEV_FW_NAME_SIZE];
1908 	char fw_name_subset[SEV_FW_NAME_SIZE];
1909 
1910 	snprintf(fw_name_specific, sizeof(fw_name_specific),
1911 		 "amd/amd_sev_fam%.2xh_model%.2xh.sbin",
1912 		 boot_cpu_data.x86, boot_cpu_data.x86_model);
1913 
1914 	snprintf(fw_name_subset, sizeof(fw_name_subset),
1915 		 "amd/amd_sev_fam%.2xh_model%.1xxh.sbin",
1916 		 boot_cpu_data.x86, (boot_cpu_data.x86_model & 0xf0) >> 4);
1917 
1918 	/* Check for SEV FW for a particular model.
1919 	 * Ex. amd_sev_fam17h_model00h.sbin for Family 17h Model 00h
1920 	 *
1921 	 * or
1922 	 *
1923 	 * Check for SEV FW common to a subset of models.
1924 	 * Ex. amd_sev_fam17h_model0xh.sbin for
1925 	 *     Family 17h Model 00h -- Family 17h Model 0Fh
1926 	 *
1927 	 * or
1928 	 *
1929 	 * Fall-back to using generic name: sev.fw
1930 	 */
1931 	if ((firmware_request_nowarn(firmware, fw_name_specific, dev) >= 0) ||
1932 	    (firmware_request_nowarn(firmware, fw_name_subset, dev) >= 0) ||
1933 	    (firmware_request_nowarn(firmware, SEV_FW_FILE, dev) >= 0))
1934 		return 0;
1935 
1936 	return -ENOENT;
1937 }
1938 
1939 /* Don't fail if SEV FW couldn't be updated. Continue with existing SEV FW */
sev_update_firmware(struct device * dev)1940 static int sev_update_firmware(struct device *dev)
1941 {
1942 	struct sev_data_download_firmware *data;
1943 	const struct firmware *firmware;
1944 	int ret, error, order;
1945 	struct page *p;
1946 	u64 data_size;
1947 
1948 	if (!sev_version_greater_or_equal(0, 15)) {
1949 		dev_dbg(dev, "DOWNLOAD_FIRMWARE not supported\n");
1950 		return -1;
1951 	}
1952 
1953 	if (sev_get_firmware(dev, &firmware) == -ENOENT) {
1954 		dev_dbg(dev, "No SEV firmware file present\n");
1955 		return -1;
1956 	}
1957 
1958 	/*
1959 	 * SEV FW expects the physical address given to it to be 32
1960 	 * byte aligned. Memory allocated has structure placed at the
1961 	 * beginning followed by the firmware being passed to the SEV
1962 	 * FW. Allocate enough memory for data structure + alignment
1963 	 * padding + SEV FW.
1964 	 */
1965 	data_size = ALIGN(sizeof(struct sev_data_download_firmware), 32);
1966 
1967 	order = get_order(firmware->size + data_size);
1968 	p = alloc_pages(GFP_KERNEL, order);
1969 	if (!p) {
1970 		ret = -1;
1971 		goto fw_err;
1972 	}
1973 
1974 	/*
1975 	 * Copy firmware data to a kernel allocated contiguous
1976 	 * memory region.
1977 	 */
1978 	data = page_address(p);
1979 	memcpy(page_address(p) + data_size, firmware->data, firmware->size);
1980 
1981 	data->address = __psp_pa(page_address(p) + data_size);
1982 	data->len = firmware->size;
1983 
1984 	ret = sev_do_cmd(SEV_CMD_DOWNLOAD_FIRMWARE, data, &error);
1985 
1986 	/*
1987 	 * A quirk for fixing the committed TCB version, when upgrading from
1988 	 * earlier firmware version than 1.50.
1989 	 */
1990 	if (!ret && !sev_version_greater_or_equal(1, 50))
1991 		ret = sev_do_cmd(SEV_CMD_DOWNLOAD_FIRMWARE, data, &error);
1992 
1993 	if (ret)
1994 		dev_dbg(dev, "Failed to update SEV firmware: %#x\n", error);
1995 
1996 	__free_pages(p, order);
1997 
1998 fw_err:
1999 	release_firmware(firmware);
2000 
2001 	return ret;
2002 }
2003 
__sev_snp_shutdown_locked(int * error,bool panic)2004 static int __sev_snp_shutdown_locked(int *error, bool panic)
2005 {
2006 	struct psp_device *psp = psp_master;
2007 	struct sev_device *sev;
2008 	struct sev_data_snp_shutdown_ex data;
2009 	int ret;
2010 
2011 	if (!psp || !psp->sev_data)
2012 		return 0;
2013 
2014 	sev = psp->sev_data;
2015 
2016 	if (!sev->snp_initialized)
2017 		return 0;
2018 
2019 	memset(&data, 0, sizeof(data));
2020 	data.len = sizeof(data);
2021 	data.iommu_snp_shutdown = 1;
2022 
2023 	/*
2024 	 * If invoked during panic handling, local interrupts are disabled
2025 	 * and all CPUs are stopped, so wbinvd_on_all_cpus() can't be called.
2026 	 * In that case, a wbinvd() is done on remote CPUs via the NMI
2027 	 * callback, so only a local wbinvd() is needed here.
2028 	 */
2029 	if (!panic)
2030 		wbinvd_on_all_cpus();
2031 	else
2032 		wbinvd();
2033 
2034 	ret = __sev_do_cmd_locked(SEV_CMD_SNP_SHUTDOWN_EX, &data, error);
2035 	/* SHUTDOWN may require DF_FLUSH */
2036 	if (*error == SEV_RET_DFFLUSH_REQUIRED) {
2037 		int dfflush_error = SEV_RET_NO_FW_CALL;
2038 
2039 		ret = __sev_do_cmd_locked(SEV_CMD_SNP_DF_FLUSH, NULL, &dfflush_error);
2040 		if (ret) {
2041 			dev_err(sev->dev, "SEV-SNP DF_FLUSH failed, ret = %d, error = %#x\n",
2042 				ret, dfflush_error);
2043 			return ret;
2044 		}
2045 		/* reissue the shutdown command */
2046 		ret = __sev_do_cmd_locked(SEV_CMD_SNP_SHUTDOWN_EX, &data,
2047 					  error);
2048 	}
2049 	if (ret) {
2050 		dev_err(sev->dev, "SEV-SNP firmware shutdown failed, rc %d, error %#x\n",
2051 			ret, *error);
2052 		return ret;
2053 	}
2054 
2055 	/*
2056 	 * SNP_SHUTDOWN_EX with IOMMU_SNP_SHUTDOWN set to 1 disables SNP
2057 	 * enforcement by the IOMMU and also transitions all pages
2058 	 * associated with the IOMMU to the Reclaim state.
2059 	 * Firmware was transitioning the IOMMU pages to Hypervisor state
2060 	 * before version 1.53. But, accounting for the number of assigned
2061 	 * 4kB pages in a 2M page was done incorrectly by not transitioning
2062 	 * to the Reclaim state. This resulted in RMP #PF when later accessing
2063 	 * the 2M page containing those pages during kexec boot. Hence, the
2064 	 * firmware now transitions these pages to Reclaim state and hypervisor
2065 	 * needs to transition these pages to shared state. SNP Firmware
2066 	 * version 1.53 and above are needed for kexec boot.
2067 	 */
2068 	ret = amd_iommu_snp_disable();
2069 	if (ret) {
2070 		dev_err(sev->dev, "SNP IOMMU shutdown failed\n");
2071 		return ret;
2072 	}
2073 
2074 	snp_leak_hv_fixed_pages();
2075 	sev->snp_initialized = false;
2076 	dev_dbg(sev->dev, "SEV-SNP firmware shutdown\n");
2077 
2078 	/*
2079 	 * __sev_snp_shutdown_locked() deadlocks when it tries to unregister
2080 	 * itself during panic as the panic notifier is called with RCU read
2081 	 * lock held and notifier unregistration does RCU synchronization.
2082 	 */
2083 	if (!panic)
2084 		atomic_notifier_chain_unregister(&panic_notifier_list,
2085 						 &snp_panic_notifier);
2086 
2087 	/* Reset TMR size back to default */
2088 	sev_es_tmr_size = SEV_TMR_SIZE;
2089 
2090 	return ret;
2091 }
2092 
sev_ioctl_do_pek_import(struct sev_issue_cmd * argp,bool writable)2093 static int sev_ioctl_do_pek_import(struct sev_issue_cmd *argp, bool writable)
2094 {
2095 	struct sev_device *sev = psp_master->sev_data;
2096 	struct sev_user_data_pek_cert_import input;
2097 	struct sev_data_pek_cert_import data;
2098 	bool shutdown_required = false;
2099 	void *pek_blob, *oca_blob;
2100 	int ret;
2101 
2102 	if (!writable)
2103 		return -EPERM;
2104 
2105 	if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
2106 		return -EFAULT;
2107 
2108 	/* copy PEK certificate blobs from userspace */
2109 	pek_blob = psp_copy_user_blob(input.pek_cert_address, input.pek_cert_len);
2110 	if (IS_ERR(pek_blob))
2111 		return PTR_ERR(pek_blob);
2112 
2113 	data.reserved = 0;
2114 	data.pek_cert_address = __psp_pa(pek_blob);
2115 	data.pek_cert_len = input.pek_cert_len;
2116 
2117 	/* copy PEK certificate blobs from userspace */
2118 	oca_blob = psp_copy_user_blob(input.oca_cert_address, input.oca_cert_len);
2119 	if (IS_ERR(oca_blob)) {
2120 		ret = PTR_ERR(oca_blob);
2121 		goto e_free_pek;
2122 	}
2123 
2124 	data.oca_cert_address = __psp_pa(oca_blob);
2125 	data.oca_cert_len = input.oca_cert_len;
2126 
2127 	/* If platform is not in INIT state then transition it to INIT */
2128 	if (sev->sev_plat_status.state != SEV_STATE_INIT) {
2129 		ret = sev_move_to_init_state(argp, &shutdown_required);
2130 		if (ret)
2131 			goto e_free_oca;
2132 	}
2133 
2134 	ret = __sev_do_cmd_locked(SEV_CMD_PEK_CERT_IMPORT, &data, &argp->error);
2135 
2136 e_free_oca:
2137 	if (shutdown_required)
2138 		__sev_firmware_shutdown(sev, false);
2139 
2140 	kfree(oca_blob);
2141 e_free_pek:
2142 	kfree(pek_blob);
2143 	return ret;
2144 }
2145 
sev_ioctl_do_get_id2(struct sev_issue_cmd * argp)2146 static int sev_ioctl_do_get_id2(struct sev_issue_cmd *argp)
2147 {
2148 	struct sev_user_data_get_id2 input;
2149 	struct sev_data_get_id data;
2150 	void __user *input_address;
2151 	void *id_blob = NULL;
2152 	int ret;
2153 
2154 	/* SEV GET_ID is available from SEV API v0.16 and up */
2155 	if (!sev_version_greater_or_equal(0, 16))
2156 		return -ENOTSUPP;
2157 
2158 	if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
2159 		return -EFAULT;
2160 
2161 	input_address = (void __user *)input.address;
2162 
2163 	if (input.address && input.length) {
2164 		/*
2165 		 * The length of the ID shouldn't be assumed by software since
2166 		 * it may change in the future.  The allocation size is limited
2167 		 * to 1 << (PAGE_SHIFT + MAX_PAGE_ORDER) by the page allocator.
2168 		 * If the allocation fails, simply return ENOMEM rather than
2169 		 * warning in the kernel log.
2170 		 */
2171 		id_blob = kzalloc(input.length, GFP_KERNEL | __GFP_NOWARN);
2172 		if (!id_blob)
2173 			return -ENOMEM;
2174 
2175 		data.address = __psp_pa(id_blob);
2176 		data.len = input.length;
2177 	} else {
2178 		data.address = 0;
2179 		data.len = 0;
2180 	}
2181 
2182 	ret = __sev_do_cmd_locked(SEV_CMD_GET_ID, &data, &argp->error);
2183 
2184 	/*
2185 	 * Firmware will return the length of the ID value (either the minimum
2186 	 * required length or the actual length written), return it to the user.
2187 	 */
2188 	input.length = data.len;
2189 
2190 	if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) {
2191 		ret = -EFAULT;
2192 		goto e_free;
2193 	}
2194 
2195 	if (id_blob) {
2196 		if (copy_to_user(input_address, id_blob, data.len)) {
2197 			ret = -EFAULT;
2198 			goto e_free;
2199 		}
2200 	}
2201 
2202 e_free:
2203 	kfree(id_blob);
2204 
2205 	return ret;
2206 }
2207 
sev_ioctl_do_get_id(struct sev_issue_cmd * argp)2208 static int sev_ioctl_do_get_id(struct sev_issue_cmd *argp)
2209 {
2210 	struct sev_data_get_id *data;
2211 	u64 data_size, user_size;
2212 	void *id_blob, *mem;
2213 	int ret;
2214 
2215 	/* SEV GET_ID available from SEV API v0.16 and up */
2216 	if (!sev_version_greater_or_equal(0, 16))
2217 		return -ENOTSUPP;
2218 
2219 	/* SEV FW expects the buffer it fills with the ID to be
2220 	 * 8-byte aligned. Memory allocated should be enough to
2221 	 * hold data structure + alignment padding + memory
2222 	 * where SEV FW writes the ID.
2223 	 */
2224 	data_size = ALIGN(sizeof(struct sev_data_get_id), 8);
2225 	user_size = sizeof(struct sev_user_data_get_id);
2226 
2227 	mem = kzalloc(data_size + user_size, GFP_KERNEL);
2228 	if (!mem)
2229 		return -ENOMEM;
2230 
2231 	data = mem;
2232 	id_blob = mem + data_size;
2233 
2234 	data->address = __psp_pa(id_blob);
2235 	data->len = user_size;
2236 
2237 	ret = __sev_do_cmd_locked(SEV_CMD_GET_ID, data, &argp->error);
2238 	if (!ret) {
2239 		if (copy_to_user((void __user *)argp->data, id_blob, data->len))
2240 			ret = -EFAULT;
2241 	}
2242 
2243 	kfree(mem);
2244 
2245 	return ret;
2246 }
2247 
sev_ioctl_do_pdh_export(struct sev_issue_cmd * argp,bool writable)2248 static int sev_ioctl_do_pdh_export(struct sev_issue_cmd *argp, bool writable)
2249 {
2250 	struct sev_device *sev = psp_master->sev_data;
2251 	struct sev_user_data_pdh_cert_export input;
2252 	void *pdh_blob = NULL, *cert_blob = NULL;
2253 	struct sev_data_pdh_cert_export data;
2254 	void __user *input_cert_chain_address;
2255 	void __user *input_pdh_cert_address;
2256 	bool shutdown_required = false;
2257 	int ret;
2258 
2259 	if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
2260 		return -EFAULT;
2261 
2262 	memset(&data, 0, sizeof(data));
2263 
2264 	input_pdh_cert_address = (void __user *)input.pdh_cert_address;
2265 	input_cert_chain_address = (void __user *)input.cert_chain_address;
2266 
2267 	/* Userspace wants to query the certificate length. */
2268 	if (!input.pdh_cert_address ||
2269 	    !input.pdh_cert_len ||
2270 	    !input.cert_chain_address)
2271 		goto cmd;
2272 
2273 	/* Allocate a physically contiguous buffer to store the PDH blob. */
2274 	if (input.pdh_cert_len > SEV_FW_BLOB_MAX_SIZE)
2275 		return -EFAULT;
2276 
2277 	/* Allocate a physically contiguous buffer to store the cert chain blob. */
2278 	if (input.cert_chain_len > SEV_FW_BLOB_MAX_SIZE)
2279 		return -EFAULT;
2280 
2281 	pdh_blob = kzalloc(input.pdh_cert_len, GFP_KERNEL);
2282 	if (!pdh_blob)
2283 		return -ENOMEM;
2284 
2285 	data.pdh_cert_address = __psp_pa(pdh_blob);
2286 	data.pdh_cert_len = input.pdh_cert_len;
2287 
2288 	cert_blob = kzalloc(input.cert_chain_len, GFP_KERNEL);
2289 	if (!cert_blob) {
2290 		ret = -ENOMEM;
2291 		goto e_free_pdh;
2292 	}
2293 
2294 	data.cert_chain_address = __psp_pa(cert_blob);
2295 	data.cert_chain_len = input.cert_chain_len;
2296 
2297 cmd:
2298 	/* If platform is not in INIT state then transition it to INIT. */
2299 	if (sev->sev_plat_status.state != SEV_STATE_INIT) {
2300 		if (!writable) {
2301 			ret = -EPERM;
2302 			goto e_free_cert;
2303 		}
2304 		ret = sev_move_to_init_state(argp, &shutdown_required);
2305 		if (ret)
2306 			goto e_free_cert;
2307 	}
2308 
2309 	ret = __sev_do_cmd_locked(SEV_CMD_PDH_CERT_EXPORT, &data, &argp->error);
2310 
2311 	/* If we query the length, FW responded with expected data. */
2312 	input.cert_chain_len = data.cert_chain_len;
2313 	input.pdh_cert_len = data.pdh_cert_len;
2314 
2315 	if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) {
2316 		ret = -EFAULT;
2317 		goto e_free_cert;
2318 	}
2319 
2320 	if (pdh_blob) {
2321 		if (copy_to_user(input_pdh_cert_address,
2322 				 pdh_blob, input.pdh_cert_len)) {
2323 			ret = -EFAULT;
2324 			goto e_free_cert;
2325 		}
2326 	}
2327 
2328 	if (cert_blob) {
2329 		if (copy_to_user(input_cert_chain_address,
2330 				 cert_blob, input.cert_chain_len))
2331 			ret = -EFAULT;
2332 	}
2333 
2334 e_free_cert:
2335 	if (shutdown_required)
2336 		__sev_firmware_shutdown(sev, false);
2337 
2338 	kfree(cert_blob);
2339 e_free_pdh:
2340 	kfree(pdh_blob);
2341 	return ret;
2342 }
2343 
sev_ioctl_do_snp_platform_status(struct sev_issue_cmd * argp)2344 static int sev_ioctl_do_snp_platform_status(struct sev_issue_cmd *argp)
2345 {
2346 	struct sev_device *sev = psp_master->sev_data;
2347 	bool shutdown_required = false;
2348 	struct sev_data_snp_addr buf;
2349 	struct page *status_page;
2350 	int ret, error;
2351 	void *data;
2352 
2353 	if (!argp->data)
2354 		return -EINVAL;
2355 
2356 	status_page = alloc_page(GFP_KERNEL_ACCOUNT);
2357 	if (!status_page)
2358 		return -ENOMEM;
2359 
2360 	data = page_address(status_page);
2361 
2362 	if (!sev->snp_initialized) {
2363 		ret = snp_move_to_init_state(argp, &shutdown_required);
2364 		if (ret)
2365 			goto cleanup;
2366 	}
2367 
2368 	/*
2369 	 * Firmware expects status page to be in firmware-owned state, otherwise
2370 	 * it will report firmware error code INVALID_PAGE_STATE (0x1A).
2371 	 */
2372 	if (rmp_mark_pages_firmware(__pa(data), 1, true)) {
2373 		ret = -EFAULT;
2374 		goto cleanup;
2375 	}
2376 
2377 	buf.address = __psp_pa(data);
2378 	ret = __sev_do_cmd_locked(SEV_CMD_SNP_PLATFORM_STATUS, &buf, &argp->error);
2379 
2380 	/*
2381 	 * Status page will be transitioned to Reclaim state upon success, or
2382 	 * left in Firmware state in failure. Use snp_reclaim_pages() to
2383 	 * transition either case back to Hypervisor-owned state.
2384 	 */
2385 	if (snp_reclaim_pages(__pa(data), 1, true))
2386 		return -EFAULT;
2387 
2388 	if (ret)
2389 		goto cleanup;
2390 
2391 	if (copy_to_user((void __user *)argp->data, data,
2392 			 sizeof(struct sev_user_data_snp_status)))
2393 		ret = -EFAULT;
2394 
2395 cleanup:
2396 	if (shutdown_required)
2397 		__sev_snp_shutdown_locked(&error, false);
2398 
2399 	__free_pages(status_page, 0);
2400 	return ret;
2401 }
2402 
sev_ioctl_do_snp_commit(struct sev_issue_cmd * argp)2403 static int sev_ioctl_do_snp_commit(struct sev_issue_cmd *argp)
2404 {
2405 	struct sev_device *sev = psp_master->sev_data;
2406 	struct sev_data_snp_commit buf;
2407 	bool shutdown_required = false;
2408 	int ret, error;
2409 
2410 	if (!sev->snp_initialized) {
2411 		ret = snp_move_to_init_state(argp, &shutdown_required);
2412 		if (ret)
2413 			return ret;
2414 	}
2415 
2416 	buf.len = sizeof(buf);
2417 
2418 	ret = __sev_do_cmd_locked(SEV_CMD_SNP_COMMIT, &buf, &argp->error);
2419 
2420 	if (shutdown_required)
2421 		__sev_snp_shutdown_locked(&error, false);
2422 
2423 	return ret;
2424 }
2425 
sev_ioctl_do_snp_set_config(struct sev_issue_cmd * argp,bool writable)2426 static int sev_ioctl_do_snp_set_config(struct sev_issue_cmd *argp, bool writable)
2427 {
2428 	struct sev_device *sev = psp_master->sev_data;
2429 	struct sev_user_data_snp_config config;
2430 	bool shutdown_required = false;
2431 	int ret, error;
2432 
2433 	if (!argp->data)
2434 		return -EINVAL;
2435 
2436 	if (!writable)
2437 		return -EPERM;
2438 
2439 	if (copy_from_user(&config, (void __user *)argp->data, sizeof(config)))
2440 		return -EFAULT;
2441 
2442 	if (!sev->snp_initialized) {
2443 		ret = snp_move_to_init_state(argp, &shutdown_required);
2444 		if (ret)
2445 			return ret;
2446 	}
2447 
2448 	ret = __sev_do_cmd_locked(SEV_CMD_SNP_CONFIG, &config, &argp->error);
2449 
2450 	if (shutdown_required)
2451 		__sev_snp_shutdown_locked(&error, false);
2452 
2453 	return ret;
2454 }
2455 
sev_ioctl_do_snp_vlek_load(struct sev_issue_cmd * argp,bool writable)2456 static int sev_ioctl_do_snp_vlek_load(struct sev_issue_cmd *argp, bool writable)
2457 {
2458 	struct sev_device *sev = psp_master->sev_data;
2459 	struct sev_user_data_snp_vlek_load input;
2460 	bool shutdown_required = false;
2461 	int ret, error;
2462 	void *blob;
2463 
2464 	if (!argp->data)
2465 		return -EINVAL;
2466 
2467 	if (!writable)
2468 		return -EPERM;
2469 
2470 	if (copy_from_user(&input, u64_to_user_ptr(argp->data), sizeof(input)))
2471 		return -EFAULT;
2472 
2473 	if (input.len != sizeof(input) || input.vlek_wrapped_version != 0)
2474 		return -EINVAL;
2475 
2476 	blob = psp_copy_user_blob(input.vlek_wrapped_address,
2477 				  sizeof(struct sev_user_data_snp_wrapped_vlek_hashstick));
2478 	if (IS_ERR(blob))
2479 		return PTR_ERR(blob);
2480 
2481 	input.vlek_wrapped_address = __psp_pa(blob);
2482 
2483 	if (!sev->snp_initialized) {
2484 		ret = snp_move_to_init_state(argp, &shutdown_required);
2485 		if (ret)
2486 			goto cleanup;
2487 	}
2488 
2489 	ret = __sev_do_cmd_locked(SEV_CMD_SNP_VLEK_LOAD, &input, &argp->error);
2490 
2491 	if (shutdown_required)
2492 		__sev_snp_shutdown_locked(&error, false);
2493 
2494 cleanup:
2495 	kfree(blob);
2496 
2497 	return ret;
2498 }
2499 
sev_ioctl(struct file * file,unsigned int ioctl,unsigned long arg)2500 static long sev_ioctl(struct file *file, unsigned int ioctl, unsigned long arg)
2501 {
2502 	void __user *argp = (void __user *)arg;
2503 	struct sev_issue_cmd input;
2504 	int ret = -EFAULT;
2505 	bool writable = file->f_mode & FMODE_WRITE;
2506 
2507 	if (!psp_master || !psp_master->sev_data)
2508 		return -ENODEV;
2509 
2510 	if (ioctl != SEV_ISSUE_CMD)
2511 		return -EINVAL;
2512 
2513 	if (copy_from_user(&input, argp, sizeof(struct sev_issue_cmd)))
2514 		return -EFAULT;
2515 
2516 	if (input.cmd > SEV_MAX)
2517 		return -EINVAL;
2518 
2519 	mutex_lock(&sev_cmd_mutex);
2520 
2521 	switch (input.cmd) {
2522 
2523 	case SEV_FACTORY_RESET:
2524 		ret = sev_ioctl_do_reset(&input, writable);
2525 		break;
2526 	case SEV_PLATFORM_STATUS:
2527 		ret = sev_ioctl_do_platform_status(&input);
2528 		break;
2529 	case SEV_PEK_GEN:
2530 		ret = sev_ioctl_do_pek_pdh_gen(SEV_CMD_PEK_GEN, &input, writable);
2531 		break;
2532 	case SEV_PDH_GEN:
2533 		ret = sev_ioctl_do_pek_pdh_gen(SEV_CMD_PDH_GEN, &input, writable);
2534 		break;
2535 	case SEV_PEK_CSR:
2536 		ret = sev_ioctl_do_pek_csr(&input, writable);
2537 		break;
2538 	case SEV_PEK_CERT_IMPORT:
2539 		ret = sev_ioctl_do_pek_import(&input, writable);
2540 		break;
2541 	case SEV_PDH_CERT_EXPORT:
2542 		ret = sev_ioctl_do_pdh_export(&input, writable);
2543 		break;
2544 	case SEV_GET_ID:
2545 		pr_warn_once("SEV_GET_ID command is deprecated, use SEV_GET_ID2\n");
2546 		ret = sev_ioctl_do_get_id(&input);
2547 		break;
2548 	case SEV_GET_ID2:
2549 		ret = sev_ioctl_do_get_id2(&input);
2550 		break;
2551 	case SNP_PLATFORM_STATUS:
2552 		ret = sev_ioctl_do_snp_platform_status(&input);
2553 		break;
2554 	case SNP_COMMIT:
2555 		ret = sev_ioctl_do_snp_commit(&input);
2556 		break;
2557 	case SNP_SET_CONFIG:
2558 		ret = sev_ioctl_do_snp_set_config(&input, writable);
2559 		break;
2560 	case SNP_VLEK_LOAD:
2561 		ret = sev_ioctl_do_snp_vlek_load(&input, writable);
2562 		break;
2563 	default:
2564 		ret = -EINVAL;
2565 		goto out;
2566 	}
2567 
2568 	if (copy_to_user(argp, &input, sizeof(struct sev_issue_cmd)))
2569 		ret = -EFAULT;
2570 out:
2571 	mutex_unlock(&sev_cmd_mutex);
2572 
2573 	return ret;
2574 }
2575 
2576 static const struct file_operations sev_fops = {
2577 	.owner	= THIS_MODULE,
2578 	.unlocked_ioctl = sev_ioctl,
2579 };
2580 
sev_platform_status(struct sev_user_data_status * data,int * error)2581 int sev_platform_status(struct sev_user_data_status *data, int *error)
2582 {
2583 	return sev_do_cmd(SEV_CMD_PLATFORM_STATUS, data, error);
2584 }
2585 EXPORT_SYMBOL_GPL(sev_platform_status);
2586 
sev_guest_deactivate(struct sev_data_deactivate * data,int * error)2587 int sev_guest_deactivate(struct sev_data_deactivate *data, int *error)
2588 {
2589 	return sev_do_cmd(SEV_CMD_DEACTIVATE, data, error);
2590 }
2591 EXPORT_SYMBOL_GPL(sev_guest_deactivate);
2592 
sev_guest_activate(struct sev_data_activate * data,int * error)2593 int sev_guest_activate(struct sev_data_activate *data, int *error)
2594 {
2595 	return sev_do_cmd(SEV_CMD_ACTIVATE, data, error);
2596 }
2597 EXPORT_SYMBOL_GPL(sev_guest_activate);
2598 
sev_guest_decommission(struct sev_data_decommission * data,int * error)2599 int sev_guest_decommission(struct sev_data_decommission *data, int *error)
2600 {
2601 	return sev_do_cmd(SEV_CMD_DECOMMISSION, data, error);
2602 }
2603 EXPORT_SYMBOL_GPL(sev_guest_decommission);
2604 
sev_guest_df_flush(int * error)2605 int sev_guest_df_flush(int *error)
2606 {
2607 	return sev_do_cmd(SEV_CMD_DF_FLUSH, NULL, error);
2608 }
2609 EXPORT_SYMBOL_GPL(sev_guest_df_flush);
2610 
sev_exit(struct kref * ref)2611 static void sev_exit(struct kref *ref)
2612 {
2613 	misc_deregister(&misc_dev->misc);
2614 	kfree(misc_dev);
2615 	misc_dev = NULL;
2616 }
2617 
sev_misc_init(struct sev_device * sev)2618 static int sev_misc_init(struct sev_device *sev)
2619 {
2620 	struct device *dev = sev->dev;
2621 	int ret;
2622 
2623 	/*
2624 	 * SEV feature support can be detected on multiple devices but the SEV
2625 	 * FW commands must be issued on the master. During probe, we do not
2626 	 * know the master hence we create /dev/sev on the first device probe.
2627 	 * sev_do_cmd() finds the right master device to which to issue the
2628 	 * command to the firmware.
2629 	 */
2630 	if (!misc_dev) {
2631 		struct miscdevice *misc;
2632 
2633 		misc_dev = kzalloc(sizeof(*misc_dev), GFP_KERNEL);
2634 		if (!misc_dev)
2635 			return -ENOMEM;
2636 
2637 		misc = &misc_dev->misc;
2638 		misc->minor = MISC_DYNAMIC_MINOR;
2639 		misc->name = DEVICE_NAME;
2640 		misc->fops = &sev_fops;
2641 
2642 		ret = misc_register(misc);
2643 		if (ret)
2644 			return ret;
2645 
2646 		kref_init(&misc_dev->refcount);
2647 	} else {
2648 		kref_get(&misc_dev->refcount);
2649 	}
2650 
2651 	init_waitqueue_head(&sev->int_queue);
2652 	sev->misc = misc_dev;
2653 	dev_dbg(dev, "registered SEV device\n");
2654 
2655 	return 0;
2656 }
2657 
sev_dev_init(struct psp_device * psp)2658 int sev_dev_init(struct psp_device *psp)
2659 {
2660 	struct device *dev = psp->dev;
2661 	struct sev_device *sev;
2662 	int ret = -ENOMEM;
2663 
2664 	if (!boot_cpu_has(X86_FEATURE_SEV)) {
2665 		dev_info_once(dev, "SEV: memory encryption not enabled by BIOS\n");
2666 		return 0;
2667 	}
2668 
2669 	sev = devm_kzalloc(dev, sizeof(*sev), GFP_KERNEL);
2670 	if (!sev)
2671 		goto e_err;
2672 
2673 	sev->cmd_buf = (void *)devm_get_free_pages(dev, GFP_KERNEL, 1);
2674 	if (!sev->cmd_buf)
2675 		goto e_sev;
2676 
2677 	sev->cmd_buf_backup = (uint8_t *)sev->cmd_buf + PAGE_SIZE;
2678 
2679 	psp->sev_data = sev;
2680 
2681 	sev->dev = dev;
2682 	sev->psp = psp;
2683 
2684 	sev->io_regs = psp->io_regs;
2685 
2686 	sev->vdata = (struct sev_vdata *)psp->vdata->sev;
2687 	if (!sev->vdata) {
2688 		ret = -ENODEV;
2689 		dev_err(dev, "sev: missing driver data\n");
2690 		goto e_buf;
2691 	}
2692 
2693 	psp_set_sev_irq_handler(psp, sev_irq_handler, sev);
2694 
2695 	ret = sev_misc_init(sev);
2696 	if (ret)
2697 		goto e_irq;
2698 
2699 	dev_notice(dev, "sev enabled\n");
2700 
2701 	return 0;
2702 
2703 e_irq:
2704 	psp_clear_sev_irq_handler(psp);
2705 e_buf:
2706 	devm_free_pages(dev, (unsigned long)sev->cmd_buf);
2707 e_sev:
2708 	devm_kfree(dev, sev);
2709 e_err:
2710 	psp->sev_data = NULL;
2711 
2712 	dev_notice(dev, "sev initialization failed\n");
2713 
2714 	return ret;
2715 }
2716 
__sev_firmware_shutdown(struct sev_device * sev,bool panic)2717 static void __sev_firmware_shutdown(struct sev_device *sev, bool panic)
2718 {
2719 	int error;
2720 
2721 	__sev_platform_shutdown_locked(&error);
2722 
2723 	if (sev_es_tmr) {
2724 		/*
2725 		 * The TMR area was encrypted, flush it from the cache.
2726 		 *
2727 		 * If invoked during panic handling, local interrupts are
2728 		 * disabled and all CPUs are stopped, so wbinvd_on_all_cpus()
2729 		 * can't be used. In that case, wbinvd() is done on remote CPUs
2730 		 * via the NMI callback, and done for this CPU later during
2731 		 * SNP shutdown, so wbinvd_on_all_cpus() can be skipped.
2732 		 */
2733 		if (!panic)
2734 			wbinvd_on_all_cpus();
2735 
2736 		__snp_free_firmware_pages(virt_to_page(sev_es_tmr),
2737 					  get_order(sev_es_tmr_size),
2738 					  true);
2739 		sev_es_tmr = NULL;
2740 	}
2741 
2742 	if (sev_init_ex_buffer) {
2743 		__snp_free_firmware_pages(virt_to_page(sev_init_ex_buffer),
2744 					  get_order(NV_LENGTH),
2745 					  true);
2746 		sev_init_ex_buffer = NULL;
2747 	}
2748 
2749 	if (snp_range_list) {
2750 		kfree(snp_range_list);
2751 		snp_range_list = NULL;
2752 	}
2753 
2754 	__sev_snp_shutdown_locked(&error, panic);
2755 }
2756 
sev_firmware_shutdown(struct sev_device * sev)2757 static void sev_firmware_shutdown(struct sev_device *sev)
2758 {
2759 	mutex_lock(&sev_cmd_mutex);
2760 	__sev_firmware_shutdown(sev, false);
2761 	mutex_unlock(&sev_cmd_mutex);
2762 }
2763 
sev_platform_shutdown(void)2764 void sev_platform_shutdown(void)
2765 {
2766 	if (!psp_master || !psp_master->sev_data)
2767 		return;
2768 
2769 	sev_firmware_shutdown(psp_master->sev_data);
2770 }
2771 EXPORT_SYMBOL_GPL(sev_platform_shutdown);
2772 
sev_dev_destroy(struct psp_device * psp)2773 void sev_dev_destroy(struct psp_device *psp)
2774 {
2775 	struct sev_device *sev = psp->sev_data;
2776 
2777 	if (!sev)
2778 		return;
2779 
2780 	sev_firmware_shutdown(sev);
2781 
2782 	if (sev->misc)
2783 		kref_put(&misc_dev->refcount, sev_exit);
2784 
2785 	psp_clear_sev_irq_handler(psp);
2786 }
2787 
snp_shutdown_on_panic(struct notifier_block * nb,unsigned long reason,void * arg)2788 static int snp_shutdown_on_panic(struct notifier_block *nb,
2789 				 unsigned long reason, void *arg)
2790 {
2791 	struct sev_device *sev = psp_master->sev_data;
2792 
2793 	/*
2794 	 * If sev_cmd_mutex is already acquired, then it's likely
2795 	 * another PSP command is in flight and issuing a shutdown
2796 	 * would fail in unexpected ways. Rather than create even
2797 	 * more confusion during a panic, just bail out here.
2798 	 */
2799 	if (mutex_is_locked(&sev_cmd_mutex))
2800 		return NOTIFY_DONE;
2801 
2802 	__sev_firmware_shutdown(sev, true);
2803 
2804 	return NOTIFY_DONE;
2805 }
2806 
sev_issue_cmd_external_user(struct file * filep,unsigned int cmd,void * data,int * error)2807 int sev_issue_cmd_external_user(struct file *filep, unsigned int cmd,
2808 				void *data, int *error)
2809 {
2810 	if (!filep || filep->f_op != &sev_fops)
2811 		return -EBADF;
2812 
2813 	return sev_do_cmd(cmd, data, error);
2814 }
2815 EXPORT_SYMBOL_GPL(sev_issue_cmd_external_user);
2816 
sev_pci_init(void)2817 void sev_pci_init(void)
2818 {
2819 	struct sev_device *sev = psp_master->sev_data;
2820 	u8 api_major, api_minor, build;
2821 
2822 	if (!sev)
2823 		return;
2824 
2825 	psp_timeout = psp_probe_timeout;
2826 
2827 	if (sev_get_api_version())
2828 		goto err;
2829 
2830 	api_major = sev->api_major;
2831 	api_minor = sev->api_minor;
2832 	build     = sev->build;
2833 
2834 	if (sev_update_firmware(sev->dev) == 0)
2835 		sev_get_api_version();
2836 
2837 	if (api_major != sev->api_major || api_minor != sev->api_minor ||
2838 	    build != sev->build)
2839 		dev_info(sev->dev, "SEV firmware updated from %d.%d.%d to %d.%d.%d\n",
2840 			 api_major, api_minor, build,
2841 			 sev->api_major, sev->api_minor, sev->build);
2842 
2843 	return;
2844 
2845 err:
2846 	sev_dev_destroy(psp_master);
2847 
2848 	psp_master->sev_data = NULL;
2849 }
2850 
sev_pci_exit(void)2851 void sev_pci_exit(void)
2852 {
2853 	struct sev_device *sev = psp_master->sev_data;
2854 
2855 	if (!sev)
2856 		return;
2857 
2858 	sev_firmware_shutdown(sev);
2859 }
2860