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 file *fp;
263 struct path root;
264 struct cred *cred;
265 const struct cred *old_cred;
266
267 task_lock(&init_task);
268 get_fs_root(init_task.fs, &root);
269 task_unlock(&init_task);
270
271 cred = prepare_creds();
272 if (!cred)
273 return ERR_PTR(-ENOMEM);
274 cred->fsuid = GLOBAL_ROOT_UID;
275 old_cred = override_creds(cred);
276
277 fp = file_open_root(&root, filename, flags, mode);
278 path_put(&root);
279
280 put_cred(revert_creds(old_cred));
281
282 return fp;
283 }
284
sev_read_init_ex_file(void)285 static int sev_read_init_ex_file(void)
286 {
287 struct sev_device *sev = psp_master->sev_data;
288 struct file *fp;
289 ssize_t nread;
290
291 lockdep_assert_held(&sev_cmd_mutex);
292
293 if (!sev_init_ex_buffer)
294 return -EOPNOTSUPP;
295
296 fp = open_file_as_root(init_ex_path, O_RDONLY, 0);
297 if (IS_ERR(fp)) {
298 int ret = PTR_ERR(fp);
299
300 if (ret == -ENOENT) {
301 dev_info(sev->dev,
302 "SEV: %s does not exist and will be created later.\n",
303 init_ex_path);
304 ret = 0;
305 } else {
306 dev_err(sev->dev,
307 "SEV: could not open %s for read, error %d\n",
308 init_ex_path, ret);
309 }
310 return ret;
311 }
312
313 nread = kernel_read(fp, sev_init_ex_buffer, NV_LENGTH, NULL);
314 if (nread != NV_LENGTH) {
315 dev_info(sev->dev,
316 "SEV: could not read %u bytes to non volatile memory area, ret %ld\n",
317 NV_LENGTH, nread);
318 }
319
320 dev_dbg(sev->dev, "SEV: read %ld bytes from NV file\n", nread);
321 filp_close(fp, NULL);
322
323 return 0;
324 }
325
sev_write_init_ex_file(void)326 static int sev_write_init_ex_file(void)
327 {
328 struct sev_device *sev = psp_master->sev_data;
329 struct file *fp;
330 loff_t offset = 0;
331 ssize_t nwrite;
332
333 lockdep_assert_held(&sev_cmd_mutex);
334
335 if (!sev_init_ex_buffer)
336 return 0;
337
338 fp = open_file_as_root(init_ex_path, O_CREAT | O_WRONLY, 0600);
339 if (IS_ERR(fp)) {
340 int ret = PTR_ERR(fp);
341
342 dev_err(sev->dev,
343 "SEV: could not open file for write, error %d\n",
344 ret);
345 return ret;
346 }
347
348 nwrite = kernel_write(fp, sev_init_ex_buffer, NV_LENGTH, &offset);
349 vfs_fsync(fp, 0);
350 filp_close(fp, NULL);
351
352 if (nwrite != NV_LENGTH) {
353 dev_err(sev->dev,
354 "SEV: failed to write %u bytes to non volatile memory area, ret %ld\n",
355 NV_LENGTH, nwrite);
356 return -EIO;
357 }
358
359 dev_dbg(sev->dev, "SEV: write successful to NV file\n");
360
361 return 0;
362 }
363
sev_write_init_ex_file_if_required(int cmd_id)364 static int sev_write_init_ex_file_if_required(int cmd_id)
365 {
366 lockdep_assert_held(&sev_cmd_mutex);
367
368 if (!sev_init_ex_buffer)
369 return 0;
370
371 /*
372 * Only a few platform commands modify the SPI/NV area, but none of the
373 * non-platform commands do. Only INIT(_EX), PLATFORM_RESET, PEK_GEN,
374 * PEK_CERT_IMPORT, and PDH_GEN do.
375 */
376 switch (cmd_id) {
377 case SEV_CMD_FACTORY_RESET:
378 case SEV_CMD_INIT_EX:
379 case SEV_CMD_PDH_GEN:
380 case SEV_CMD_PEK_CERT_IMPORT:
381 case SEV_CMD_PEK_GEN:
382 break;
383 default:
384 return 0;
385 }
386
387 return sev_write_init_ex_file();
388 }
389
390 /*
391 * snp_reclaim_pages() needs __sev_do_cmd_locked(), and __sev_do_cmd_locked()
392 * needs snp_reclaim_pages(), so a forward declaration is needed.
393 */
394 static int __sev_do_cmd_locked(int cmd, void *data, int *psp_ret);
395
snp_reclaim_pages(unsigned long paddr,unsigned int npages,bool locked)396 static int snp_reclaim_pages(unsigned long paddr, unsigned int npages, bool locked)
397 {
398 int ret, err, i;
399
400 paddr = __sme_clr(ALIGN_DOWN(paddr, PAGE_SIZE));
401
402 for (i = 0; i < npages; i++, paddr += PAGE_SIZE) {
403 struct sev_data_snp_page_reclaim data = {0};
404
405 data.paddr = paddr;
406
407 if (locked)
408 ret = __sev_do_cmd_locked(SEV_CMD_SNP_PAGE_RECLAIM, &data, &err);
409 else
410 ret = sev_do_cmd(SEV_CMD_SNP_PAGE_RECLAIM, &data, &err);
411
412 if (ret)
413 goto cleanup;
414
415 ret = rmp_make_shared(__phys_to_pfn(paddr), PG_LEVEL_4K);
416 if (ret)
417 goto cleanup;
418 }
419
420 return 0;
421
422 cleanup:
423 /*
424 * If there was a failure reclaiming the page then it is no longer safe
425 * to release it back to the system; leak it instead.
426 */
427 snp_leak_pages(__phys_to_pfn(paddr), npages - i);
428 return ret;
429 }
430
rmp_mark_pages_firmware(unsigned long paddr,unsigned int npages,bool locked)431 static int rmp_mark_pages_firmware(unsigned long paddr, unsigned int npages, bool locked)
432 {
433 unsigned long pfn = __sme_clr(paddr) >> PAGE_SHIFT;
434 int rc, i;
435
436 for (i = 0; i < npages; i++, pfn++) {
437 rc = rmp_make_private(pfn, 0, PG_LEVEL_4K, 0, true);
438 if (rc)
439 goto cleanup;
440 }
441
442 return 0;
443
444 cleanup:
445 /*
446 * Try unrolling the firmware state changes by
447 * reclaiming the pages which were already changed to the
448 * firmware state.
449 */
450 snp_reclaim_pages(paddr, i, locked);
451
452 return rc;
453 }
454
__snp_alloc_firmware_pages(gfp_t gfp_mask,int order,bool locked)455 static struct page *__snp_alloc_firmware_pages(gfp_t gfp_mask, int order, bool locked)
456 {
457 unsigned long npages = 1ul << order, paddr;
458 struct sev_device *sev;
459 struct page *page;
460
461 if (!psp_master || !psp_master->sev_data)
462 return NULL;
463
464 page = alloc_pages(gfp_mask, order);
465 if (!page)
466 return NULL;
467
468 /* If SEV-SNP is initialized then add the page in RMP table. */
469 sev = psp_master->sev_data;
470 if (!sev->snp_initialized)
471 return page;
472
473 paddr = __pa((unsigned long)page_address(page));
474 if (rmp_mark_pages_firmware(paddr, npages, locked))
475 return NULL;
476
477 return page;
478 }
479
snp_alloc_firmware_page(gfp_t gfp_mask)480 void *snp_alloc_firmware_page(gfp_t gfp_mask)
481 {
482 struct page *page;
483
484 page = __snp_alloc_firmware_pages(gfp_mask, 0, false);
485
486 return page ? page_address(page) : NULL;
487 }
488 EXPORT_SYMBOL_GPL(snp_alloc_firmware_page);
489
__snp_free_firmware_pages(struct page * page,int order,bool locked)490 static void __snp_free_firmware_pages(struct page *page, int order, bool locked)
491 {
492 struct sev_device *sev = psp_master->sev_data;
493 unsigned long paddr, npages = 1ul << order;
494
495 if (!page)
496 return;
497
498 paddr = __pa((unsigned long)page_address(page));
499 if (sev->snp_initialized &&
500 snp_reclaim_pages(paddr, npages, locked))
501 return;
502
503 __free_pages(page, order);
504 }
505
snp_free_firmware_page(void * addr)506 void snp_free_firmware_page(void *addr)
507 {
508 if (!addr)
509 return;
510
511 __snp_free_firmware_pages(virt_to_page(addr), 0, false);
512 }
513 EXPORT_SYMBOL_GPL(snp_free_firmware_page);
514
sev_fw_alloc(unsigned long len)515 static void *sev_fw_alloc(unsigned long len)
516 {
517 struct page *page;
518
519 page = __snp_alloc_firmware_pages(GFP_KERNEL, get_order(len), true);
520 if (!page)
521 return NULL;
522
523 return page_address(page);
524 }
525
526 /**
527 * struct cmd_buf_desc - descriptors for managing legacy SEV command address
528 * parameters corresponding to buffers that may be written to by firmware.
529 *
530 * @paddr_ptr: pointer to the address parameter in the command buffer which may
531 * need to be saved/restored depending on whether a bounce buffer
532 * is used. In the case of a bounce buffer, the command buffer
533 * needs to be updated with the address of the new bounce buffer
534 * snp_map_cmd_buf_desc() has allocated specifically for it. Must
535 * be NULL if this descriptor is only an end-of-list indicator.
536 *
537 * @paddr_orig: storage for the original address parameter, which can be used to
538 * restore the original value in @paddr_ptr in cases where it is
539 * replaced with the address of a bounce buffer.
540 *
541 * @len: length of buffer located at the address originally stored at @paddr_ptr
542 *
543 * @guest_owned: true if the address corresponds to guest-owned pages, in which
544 * case bounce buffers are not needed.
545 */
546 struct cmd_buf_desc {
547 u64 *paddr_ptr;
548 u64 paddr_orig;
549 u32 len;
550 bool guest_owned;
551 };
552
553 /*
554 * If a legacy SEV command parameter is a memory address, those pages in
555 * turn need to be transitioned to/from firmware-owned before/after
556 * executing the firmware command.
557 *
558 * Additionally, in cases where those pages are not guest-owned, a bounce
559 * buffer is needed in place of the original memory address parameter.
560 *
561 * A set of descriptors are used to keep track of this handling, and
562 * initialized here based on the specific commands being executed.
563 */
snp_populate_cmd_buf_desc_list(int cmd,void * cmd_buf,struct cmd_buf_desc * desc_list)564 static void snp_populate_cmd_buf_desc_list(int cmd, void *cmd_buf,
565 struct cmd_buf_desc *desc_list)
566 {
567 switch (cmd) {
568 case SEV_CMD_PDH_CERT_EXPORT: {
569 struct sev_data_pdh_cert_export *data = cmd_buf;
570
571 desc_list[0].paddr_ptr = &data->pdh_cert_address;
572 desc_list[0].len = data->pdh_cert_len;
573 desc_list[1].paddr_ptr = &data->cert_chain_address;
574 desc_list[1].len = data->cert_chain_len;
575 break;
576 }
577 case SEV_CMD_GET_ID: {
578 struct sev_data_get_id *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_PEK_CSR: {
585 struct sev_data_pek_csr *data = cmd_buf;
586
587 desc_list[0].paddr_ptr = &data->address;
588 desc_list[0].len = data->len;
589 break;
590 }
591 case SEV_CMD_LAUNCH_UPDATE_DATA: {
592 struct sev_data_launch_update_data *data = cmd_buf;
593
594 desc_list[0].paddr_ptr = &data->address;
595 desc_list[0].len = data->len;
596 desc_list[0].guest_owned = true;
597 break;
598 }
599 case SEV_CMD_LAUNCH_UPDATE_VMSA: {
600 struct sev_data_launch_update_vmsa *data = cmd_buf;
601
602 desc_list[0].paddr_ptr = &data->address;
603 desc_list[0].len = data->len;
604 desc_list[0].guest_owned = true;
605 break;
606 }
607 case SEV_CMD_LAUNCH_MEASURE: {
608 struct sev_data_launch_measure *data = cmd_buf;
609
610 desc_list[0].paddr_ptr = &data->address;
611 desc_list[0].len = data->len;
612 break;
613 }
614 case SEV_CMD_LAUNCH_UPDATE_SECRET: {
615 struct sev_data_launch_secret *data = cmd_buf;
616
617 desc_list[0].paddr_ptr = &data->guest_address;
618 desc_list[0].len = data->guest_len;
619 desc_list[0].guest_owned = true;
620 break;
621 }
622 case SEV_CMD_DBG_DECRYPT: {
623 struct sev_data_dbg *data = cmd_buf;
624
625 desc_list[0].paddr_ptr = &data->dst_addr;
626 desc_list[0].len = data->len;
627 desc_list[0].guest_owned = true;
628 break;
629 }
630 case SEV_CMD_DBG_ENCRYPT: {
631 struct sev_data_dbg *data = cmd_buf;
632
633 desc_list[0].paddr_ptr = &data->dst_addr;
634 desc_list[0].len = data->len;
635 desc_list[0].guest_owned = true;
636 break;
637 }
638 case SEV_CMD_ATTESTATION_REPORT: {
639 struct sev_data_attestation_report *data = cmd_buf;
640
641 desc_list[0].paddr_ptr = &data->address;
642 desc_list[0].len = data->len;
643 break;
644 }
645 case SEV_CMD_SEND_START: {
646 struct sev_data_send_start *data = cmd_buf;
647
648 desc_list[0].paddr_ptr = &data->session_address;
649 desc_list[0].len = data->session_len;
650 break;
651 }
652 case SEV_CMD_SEND_UPDATE_DATA: {
653 struct sev_data_send_update_data *data = cmd_buf;
654
655 desc_list[0].paddr_ptr = &data->hdr_address;
656 desc_list[0].len = data->hdr_len;
657 desc_list[1].paddr_ptr = &data->trans_address;
658 desc_list[1].len = data->trans_len;
659 break;
660 }
661 case SEV_CMD_SEND_UPDATE_VMSA: {
662 struct sev_data_send_update_vmsa *data = cmd_buf;
663
664 desc_list[0].paddr_ptr = &data->hdr_address;
665 desc_list[0].len = data->hdr_len;
666 desc_list[1].paddr_ptr = &data->trans_address;
667 desc_list[1].len = data->trans_len;
668 break;
669 }
670 case SEV_CMD_RECEIVE_UPDATE_DATA: {
671 struct sev_data_receive_update_data *data = cmd_buf;
672
673 desc_list[0].paddr_ptr = &data->guest_address;
674 desc_list[0].len = data->guest_len;
675 desc_list[0].guest_owned = true;
676 break;
677 }
678 case SEV_CMD_RECEIVE_UPDATE_VMSA: {
679 struct sev_data_receive_update_vmsa *data = cmd_buf;
680
681 desc_list[0].paddr_ptr = &data->guest_address;
682 desc_list[0].len = data->guest_len;
683 desc_list[0].guest_owned = true;
684 break;
685 }
686 default:
687 break;
688 }
689 }
690
snp_map_cmd_buf_desc(struct cmd_buf_desc * desc)691 static int snp_map_cmd_buf_desc(struct cmd_buf_desc *desc)
692 {
693 unsigned int npages;
694
695 if (!desc->len)
696 return 0;
697
698 /* Allocate a bounce buffer if this isn't a guest owned page. */
699 if (!desc->guest_owned) {
700 struct page *page;
701
702 page = alloc_pages(GFP_KERNEL_ACCOUNT, get_order(desc->len));
703 if (!page) {
704 pr_warn("Failed to allocate bounce buffer for SEV legacy command.\n");
705 return -ENOMEM;
706 }
707
708 desc->paddr_orig = *desc->paddr_ptr;
709 *desc->paddr_ptr = __psp_pa(page_to_virt(page));
710 }
711
712 npages = PAGE_ALIGN(desc->len) >> PAGE_SHIFT;
713
714 /* Transition the buffer to firmware-owned. */
715 if (rmp_mark_pages_firmware(*desc->paddr_ptr, npages, true)) {
716 pr_warn("Error moving pages to firmware-owned state for SEV legacy command.\n");
717 return -EFAULT;
718 }
719
720 return 0;
721 }
722
snp_unmap_cmd_buf_desc(struct cmd_buf_desc * desc)723 static int snp_unmap_cmd_buf_desc(struct cmd_buf_desc *desc)
724 {
725 unsigned int npages;
726
727 if (!desc->len)
728 return 0;
729
730 npages = PAGE_ALIGN(desc->len) >> PAGE_SHIFT;
731
732 /* Transition the buffers back to hypervisor-owned. */
733 if (snp_reclaim_pages(*desc->paddr_ptr, npages, true)) {
734 pr_warn("Failed to reclaim firmware-owned pages while issuing SEV legacy command.\n");
735 return -EFAULT;
736 }
737
738 /* Copy data from bounce buffer and then free it. */
739 if (!desc->guest_owned) {
740 void *bounce_buf = __va(__sme_clr(*desc->paddr_ptr));
741 void *dst_buf = __va(__sme_clr(desc->paddr_orig));
742
743 memcpy(dst_buf, bounce_buf, desc->len);
744 __free_pages(virt_to_page(bounce_buf), get_order(desc->len));
745
746 /* Restore the original address in the command buffer. */
747 *desc->paddr_ptr = desc->paddr_orig;
748 }
749
750 return 0;
751 }
752
snp_map_cmd_buf_desc_list(int cmd,void * cmd_buf,struct cmd_buf_desc * desc_list)753 static int snp_map_cmd_buf_desc_list(int cmd, void *cmd_buf, struct cmd_buf_desc *desc_list)
754 {
755 int i;
756
757 snp_populate_cmd_buf_desc_list(cmd, cmd_buf, desc_list);
758
759 for (i = 0; i < CMD_BUF_DESC_MAX; i++) {
760 struct cmd_buf_desc *desc = &desc_list[i];
761
762 if (!desc->paddr_ptr)
763 break;
764
765 if (snp_map_cmd_buf_desc(desc))
766 goto err_unmap;
767 }
768
769 return 0;
770
771 err_unmap:
772 for (i--; i >= 0; i--)
773 snp_unmap_cmd_buf_desc(&desc_list[i]);
774
775 return -EFAULT;
776 }
777
snp_unmap_cmd_buf_desc_list(struct cmd_buf_desc * desc_list)778 static int snp_unmap_cmd_buf_desc_list(struct cmd_buf_desc *desc_list)
779 {
780 int i, ret = 0;
781
782 for (i = 0; i < CMD_BUF_DESC_MAX; i++) {
783 struct cmd_buf_desc *desc = &desc_list[i];
784
785 if (!desc->paddr_ptr)
786 break;
787
788 if (snp_unmap_cmd_buf_desc(&desc_list[i]))
789 ret = -EFAULT;
790 }
791
792 return ret;
793 }
794
sev_cmd_buf_writable(int cmd)795 static bool sev_cmd_buf_writable(int cmd)
796 {
797 switch (cmd) {
798 case SEV_CMD_PLATFORM_STATUS:
799 case SEV_CMD_GUEST_STATUS:
800 case SEV_CMD_LAUNCH_START:
801 case SEV_CMD_RECEIVE_START:
802 case SEV_CMD_LAUNCH_MEASURE:
803 case SEV_CMD_SEND_START:
804 case SEV_CMD_SEND_UPDATE_DATA:
805 case SEV_CMD_SEND_UPDATE_VMSA:
806 case SEV_CMD_PEK_CSR:
807 case SEV_CMD_PDH_CERT_EXPORT:
808 case SEV_CMD_GET_ID:
809 case SEV_CMD_ATTESTATION_REPORT:
810 return true;
811 default:
812 return false;
813 }
814 }
815
816 /* After SNP is INIT'ed, the behavior of legacy SEV commands is changed. */
snp_legacy_handling_needed(int cmd)817 static bool snp_legacy_handling_needed(int cmd)
818 {
819 struct sev_device *sev = psp_master->sev_data;
820
821 return cmd < SEV_CMD_SNP_INIT && sev->snp_initialized;
822 }
823
snp_prep_cmd_buf(int cmd,void * cmd_buf,struct cmd_buf_desc * desc_list)824 static int snp_prep_cmd_buf(int cmd, void *cmd_buf, struct cmd_buf_desc *desc_list)
825 {
826 if (!snp_legacy_handling_needed(cmd))
827 return 0;
828
829 if (snp_map_cmd_buf_desc_list(cmd, cmd_buf, desc_list))
830 return -EFAULT;
831
832 /*
833 * Before command execution, the command buffer needs to be put into
834 * the firmware-owned state.
835 */
836 if (sev_cmd_buf_writable(cmd)) {
837 if (rmp_mark_pages_firmware(__pa(cmd_buf), 1, true))
838 return -EFAULT;
839 }
840
841 return 0;
842 }
843
snp_reclaim_cmd_buf(int cmd,void * cmd_buf)844 static int snp_reclaim_cmd_buf(int cmd, void *cmd_buf)
845 {
846 if (!snp_legacy_handling_needed(cmd))
847 return 0;
848
849 /*
850 * After command completion, the command buffer needs to be put back
851 * into the hypervisor-owned state.
852 */
853 if (sev_cmd_buf_writable(cmd))
854 if (snp_reclaim_pages(__pa(cmd_buf), 1, true))
855 return -EFAULT;
856
857 return 0;
858 }
859
__sev_do_cmd_locked(int cmd,void * data,int * psp_ret)860 static int __sev_do_cmd_locked(int cmd, void *data, int *psp_ret)
861 {
862 struct cmd_buf_desc desc_list[CMD_BUF_DESC_MAX] = {0};
863 struct psp_device *psp = psp_master;
864 struct sev_device *sev;
865 unsigned int cmdbuff_hi, cmdbuff_lo;
866 unsigned int phys_lsb, phys_msb;
867 unsigned int reg;
868 void *cmd_buf;
869 int buf_len;
870 int ret = 0;
871
872 if (!psp || !psp->sev_data)
873 return -ENODEV;
874
875 if (psp_dead)
876 return -EBUSY;
877
878 sev = psp->sev_data;
879
880 buf_len = sev_cmd_buffer_len(cmd);
881 if (WARN_ON_ONCE(!data != !buf_len))
882 return -EINVAL;
883
884 /*
885 * Copy the incoming data to driver's scratch buffer as __pa() will not
886 * work for some memory, e.g. vmalloc'd addresses, and @data may not be
887 * physically contiguous.
888 */
889 if (data) {
890 /*
891 * Commands are generally issued one at a time and require the
892 * sev_cmd_mutex, but there could be recursive firmware requests
893 * due to SEV_CMD_SNP_PAGE_RECLAIM needing to be issued while
894 * preparing buffers for another command. This is the only known
895 * case of nesting in the current code, so exactly one
896 * additional command buffer is available for that purpose.
897 */
898 if (!sev->cmd_buf_active) {
899 cmd_buf = sev->cmd_buf;
900 sev->cmd_buf_active = true;
901 } else if (!sev->cmd_buf_backup_active) {
902 cmd_buf = sev->cmd_buf_backup;
903 sev->cmd_buf_backup_active = true;
904 } else {
905 dev_err(sev->dev,
906 "SEV: too many firmware commands in progress, no command buffers available.\n");
907 return -EBUSY;
908 }
909
910 memcpy(cmd_buf, data, buf_len);
911
912 /*
913 * The behavior of the SEV-legacy commands is altered when the
914 * SNP firmware is in the INIT state.
915 */
916 ret = snp_prep_cmd_buf(cmd, cmd_buf, desc_list);
917 if (ret) {
918 dev_err(sev->dev,
919 "SEV: failed to prepare buffer for legacy command 0x%x. Error: %d\n",
920 cmd, ret);
921 return ret;
922 }
923 } else {
924 cmd_buf = sev->cmd_buf;
925 }
926
927 /* Get the physical address of the command buffer */
928 phys_lsb = data ? lower_32_bits(__psp_pa(cmd_buf)) : 0;
929 phys_msb = data ? upper_32_bits(__psp_pa(cmd_buf)) : 0;
930
931 dev_dbg(sev->dev, "sev command id %#x buffer 0x%08x%08x timeout %us\n",
932 cmd, phys_msb, phys_lsb, psp_timeout);
933
934 print_hex_dump_debug("(in): ", DUMP_PREFIX_OFFSET, 16, 2, data,
935 buf_len, false);
936
937 iowrite32(phys_lsb, sev->io_regs + sev->vdata->cmdbuff_addr_lo_reg);
938 iowrite32(phys_msb, sev->io_regs + sev->vdata->cmdbuff_addr_hi_reg);
939
940 sev->int_rcvd = 0;
941
942 reg = FIELD_PREP(SEV_CMDRESP_CMD, cmd);
943
944 /*
945 * If invoked during panic handling, local interrupts are disabled so
946 * the PSP command completion interrupt can't be used.
947 * sev_wait_cmd_ioc() already checks for interrupts disabled and
948 * polls for PSP command completion. Ensure we do not request an
949 * interrupt from the PSP if irqs disabled.
950 */
951 if (!irqs_disabled())
952 reg |= SEV_CMDRESP_IOC;
953
954 iowrite32(reg, sev->io_regs + sev->vdata->cmdresp_reg);
955
956 /* wait for command completion */
957 ret = sev_wait_cmd_ioc(sev, ®, psp_timeout);
958 if (ret) {
959 if (psp_ret)
960 *psp_ret = 0;
961
962 dev_err(sev->dev, "sev command %#x timed out, disabling PSP\n", cmd);
963 psp_dead = true;
964
965 return ret;
966 }
967
968 psp_timeout = psp_cmd_timeout;
969
970 if (psp_ret)
971 *psp_ret = FIELD_GET(PSP_CMDRESP_STS, reg);
972
973 if (FIELD_GET(PSP_CMDRESP_STS, reg)) {
974 dev_dbg(sev->dev, "sev command %#x failed (%#010lx)\n",
975 cmd, FIELD_GET(PSP_CMDRESP_STS, reg));
976
977 /*
978 * PSP firmware may report additional error information in the
979 * command buffer registers on error. Print contents of command
980 * buffer registers if they changed.
981 */
982 cmdbuff_hi = ioread32(sev->io_regs + sev->vdata->cmdbuff_addr_hi_reg);
983 cmdbuff_lo = ioread32(sev->io_regs + sev->vdata->cmdbuff_addr_lo_reg);
984 if (cmdbuff_hi != phys_msb || cmdbuff_lo != phys_lsb) {
985 dev_dbg(sev->dev, "Additional error information reported in cmdbuff:");
986 dev_dbg(sev->dev, " cmdbuff hi: %#010x\n", cmdbuff_hi);
987 dev_dbg(sev->dev, " cmdbuff lo: %#010x\n", cmdbuff_lo);
988 }
989 ret = -EIO;
990 } else {
991 ret = sev_write_init_ex_file_if_required(cmd);
992 }
993
994 /*
995 * Copy potential output from the PSP back to data. Do this even on
996 * failure in case the caller wants to glean something from the error.
997 */
998 if (data) {
999 int ret_reclaim;
1000 /*
1001 * Restore the page state after the command completes.
1002 */
1003 ret_reclaim = snp_reclaim_cmd_buf(cmd, cmd_buf);
1004 if (ret_reclaim) {
1005 dev_err(sev->dev,
1006 "SEV: failed to reclaim buffer for legacy command %#x. Error: %d\n",
1007 cmd, ret_reclaim);
1008 return ret_reclaim;
1009 }
1010
1011 memcpy(data, cmd_buf, buf_len);
1012
1013 if (sev->cmd_buf_backup_active)
1014 sev->cmd_buf_backup_active = false;
1015 else
1016 sev->cmd_buf_active = false;
1017
1018 if (snp_unmap_cmd_buf_desc_list(desc_list))
1019 return -EFAULT;
1020 }
1021
1022 print_hex_dump_debug("(out): ", DUMP_PREFIX_OFFSET, 16, 2, data,
1023 buf_len, false);
1024
1025 return ret;
1026 }
1027
sev_do_cmd(int cmd,void * data,int * psp_ret)1028 int sev_do_cmd(int cmd, void *data, int *psp_ret)
1029 {
1030 int rc;
1031
1032 mutex_lock(&sev_cmd_mutex);
1033 rc = __sev_do_cmd_locked(cmd, data, psp_ret);
1034 mutex_unlock(&sev_cmd_mutex);
1035
1036 return rc;
1037 }
1038 EXPORT_SYMBOL_GPL(sev_do_cmd);
1039
__sev_init_locked(int * error)1040 static int __sev_init_locked(int *error)
1041 {
1042 struct sev_data_init data;
1043
1044 memset(&data, 0, sizeof(data));
1045 if (sev_es_tmr) {
1046 /*
1047 * Do not include the encryption mask on the physical
1048 * address of the TMR (firmware should clear it anyway).
1049 */
1050 data.tmr_address = __pa(sev_es_tmr);
1051
1052 data.flags |= SEV_INIT_FLAGS_SEV_ES;
1053 data.tmr_len = sev_es_tmr_size;
1054 }
1055
1056 return __sev_do_cmd_locked(SEV_CMD_INIT, &data, error);
1057 }
1058
__sev_init_ex_locked(int * error)1059 static int __sev_init_ex_locked(int *error)
1060 {
1061 struct sev_data_init_ex data;
1062
1063 memset(&data, 0, sizeof(data));
1064 data.length = sizeof(data);
1065 data.nv_address = __psp_pa(sev_init_ex_buffer);
1066 data.nv_len = NV_LENGTH;
1067
1068 if (sev_es_tmr) {
1069 /*
1070 * Do not include the encryption mask on the physical
1071 * address of the TMR (firmware should clear it anyway).
1072 */
1073 data.tmr_address = __pa(sev_es_tmr);
1074
1075 data.flags |= SEV_INIT_FLAGS_SEV_ES;
1076 data.tmr_len = sev_es_tmr_size;
1077 }
1078
1079 return __sev_do_cmd_locked(SEV_CMD_INIT_EX, &data, error);
1080 }
1081
__sev_do_init_locked(int * psp_ret)1082 static inline int __sev_do_init_locked(int *psp_ret)
1083 {
1084 if (sev_init_ex_buffer)
1085 return __sev_init_ex_locked(psp_ret);
1086 else
1087 return __sev_init_locked(psp_ret);
1088 }
1089
snp_set_hsave_pa(void * arg)1090 static void snp_set_hsave_pa(void *arg)
1091 {
1092 wrmsrq(MSR_VM_HSAVE_PA, 0);
1093 }
1094
1095 /* Hypervisor Fixed pages API interface */
snp_hv_fixed_pages_state_update(struct sev_device * sev,enum snp_hv_fixed_pages_state page_state)1096 static void snp_hv_fixed_pages_state_update(struct sev_device *sev,
1097 enum snp_hv_fixed_pages_state page_state)
1098 {
1099 struct snp_hv_fixed_pages_entry *entry;
1100
1101 /* List is protected by sev_cmd_mutex */
1102 lockdep_assert_held(&sev_cmd_mutex);
1103
1104 if (list_empty(&snp_hv_fixed_pages))
1105 return;
1106
1107 list_for_each_entry(entry, &snp_hv_fixed_pages, list)
1108 entry->page_state = page_state;
1109 }
1110
1111 /*
1112 * Allocate HV_FIXED pages in 2MB aligned sizes to ensure the whole
1113 * 2MB pages are marked as HV_FIXED.
1114 */
snp_alloc_hv_fixed_pages(unsigned int num_2mb_pages)1115 struct page *snp_alloc_hv_fixed_pages(unsigned int num_2mb_pages)
1116 {
1117 struct psp_device *psp_master = psp_get_master_device();
1118 struct snp_hv_fixed_pages_entry *entry;
1119 struct sev_device *sev;
1120 unsigned int order;
1121 struct page *page;
1122
1123 if (!psp_master || !psp_master->sev_data)
1124 return NULL;
1125
1126 sev = psp_master->sev_data;
1127
1128 order = get_order(PMD_SIZE * num_2mb_pages);
1129
1130 /*
1131 * SNP_INIT_EX is protected by sev_cmd_mutex, therefore this list
1132 * also needs to be protected using the same mutex.
1133 */
1134 guard(mutex)(&sev_cmd_mutex);
1135
1136 /*
1137 * This API uses SNP_INIT_EX to transition allocated pages to HV_Fixed
1138 * page state, fail if SNP is already initialized.
1139 */
1140 if (sev->snp_initialized)
1141 return NULL;
1142
1143 /* Re-use freed pages that match the request */
1144 list_for_each_entry(entry, &snp_hv_fixed_pages, list) {
1145 /* Hypervisor fixed page allocator implements exact fit policy */
1146 if (entry->order == order && entry->free) {
1147 entry->free = false;
1148 memset(page_address(entry->page), 0,
1149 (1 << entry->order) * PAGE_SIZE);
1150 return entry->page;
1151 }
1152 }
1153
1154 page = alloc_pages(GFP_KERNEL | __GFP_ZERO, order);
1155 if (!page)
1156 return NULL;
1157
1158 entry = kzalloc(sizeof(*entry), GFP_KERNEL);
1159 if (!entry) {
1160 __free_pages(page, order);
1161 return NULL;
1162 }
1163
1164 entry->page = page;
1165 entry->order = order;
1166 list_add_tail(&entry->list, &snp_hv_fixed_pages);
1167
1168 return page;
1169 }
1170
snp_free_hv_fixed_pages(struct page * page)1171 void snp_free_hv_fixed_pages(struct page *page)
1172 {
1173 struct psp_device *psp_master = psp_get_master_device();
1174 struct snp_hv_fixed_pages_entry *entry, *nentry;
1175
1176 if (!psp_master || !psp_master->sev_data)
1177 return;
1178
1179 /*
1180 * SNP_INIT_EX is protected by sev_cmd_mutex, therefore this list
1181 * also needs to be protected using the same mutex.
1182 */
1183 guard(mutex)(&sev_cmd_mutex);
1184
1185 list_for_each_entry_safe(entry, nentry, &snp_hv_fixed_pages, list) {
1186 if (entry->page != page)
1187 continue;
1188
1189 /*
1190 * HV_FIXED page state cannot be changed until reboot
1191 * and they cannot be used by an SNP guest, so they cannot
1192 * be returned back to the page allocator.
1193 * Mark the pages as free internally to allow possible re-use.
1194 */
1195 if (entry->page_state == HV_FIXED) {
1196 entry->free = true;
1197 } else {
1198 __free_pages(page, entry->order);
1199 list_del(&entry->list);
1200 kfree(entry);
1201 }
1202 return;
1203 }
1204 }
1205
snp_add_hv_fixed_pages(struct sev_device * sev,struct sev_data_range_list * range_list)1206 static void snp_add_hv_fixed_pages(struct sev_device *sev, struct sev_data_range_list *range_list)
1207 {
1208 struct snp_hv_fixed_pages_entry *entry;
1209 struct sev_data_range *range;
1210 int num_elements;
1211
1212 lockdep_assert_held(&sev_cmd_mutex);
1213
1214 if (list_empty(&snp_hv_fixed_pages))
1215 return;
1216
1217 num_elements = list_count_nodes(&snp_hv_fixed_pages) +
1218 range_list->num_elements;
1219
1220 /*
1221 * Ensure the list of HV_FIXED pages that will be passed to firmware
1222 * do not exceed the page-sized argument buffer.
1223 */
1224 if (num_elements * sizeof(*range) + sizeof(*range_list) > PAGE_SIZE) {
1225 dev_warn(sev->dev, "Additional HV_Fixed pages cannot be accommodated, omitting\n");
1226 return;
1227 }
1228
1229 range = &range_list->ranges[range_list->num_elements];
1230 list_for_each_entry(entry, &snp_hv_fixed_pages, list) {
1231 range->base = page_to_pfn(entry->page) << PAGE_SHIFT;
1232 range->page_count = 1 << entry->order;
1233 range++;
1234 }
1235 range_list->num_elements = num_elements;
1236 }
1237
snp_leak_hv_fixed_pages(void)1238 static void snp_leak_hv_fixed_pages(void)
1239 {
1240 struct snp_hv_fixed_pages_entry *entry;
1241
1242 /* List is protected by sev_cmd_mutex */
1243 lockdep_assert_held(&sev_cmd_mutex);
1244
1245 if (list_empty(&snp_hv_fixed_pages))
1246 return;
1247
1248 list_for_each_entry(entry, &snp_hv_fixed_pages, list)
1249 if (entry->page_state == HV_FIXED)
1250 __snp_leak_pages(page_to_pfn(entry->page),
1251 1 << entry->order, false);
1252 }
1253
sev_is_snp_ciphertext_hiding_supported(void)1254 bool sev_is_snp_ciphertext_hiding_supported(void)
1255 {
1256 struct psp_device *psp = psp_master;
1257 struct sev_device *sev;
1258
1259 if (!psp || !psp->sev_data)
1260 return false;
1261
1262 sev = psp->sev_data;
1263
1264 /*
1265 * Feature information indicates if CipherTextHiding feature is
1266 * supported by the SEV firmware and additionally platform status
1267 * indicates if CipherTextHiding feature is enabled in the
1268 * Platform BIOS.
1269 */
1270 return ((sev->snp_feat_info_0.ecx & SNP_CIPHER_TEXT_HIDING_SUPPORTED) &&
1271 sev->snp_plat_status.ciphertext_hiding_cap);
1272 }
1273 EXPORT_SYMBOL_GPL(sev_is_snp_ciphertext_hiding_supported);
1274
snp_get_platform_data(struct sev_device * sev,int * error)1275 static int snp_get_platform_data(struct sev_device *sev, int *error)
1276 {
1277 struct sev_data_snp_feature_info snp_feat_info;
1278 struct snp_feature_info *feat_info;
1279 struct sev_data_snp_addr buf;
1280 struct page *page;
1281 int rc;
1282
1283 /*
1284 * This function is expected to be called before SNP is
1285 * initialized.
1286 */
1287 if (sev->snp_initialized)
1288 return -EINVAL;
1289
1290 buf.address = __psp_pa(&sev->snp_plat_status);
1291 rc = sev_do_cmd(SEV_CMD_SNP_PLATFORM_STATUS, &buf, error);
1292 if (rc) {
1293 dev_err(sev->dev, "SNP PLATFORM_STATUS command failed, ret = %d, error = %#x\n",
1294 rc, *error);
1295 return rc;
1296 }
1297
1298 sev->api_major = sev->snp_plat_status.api_major;
1299 sev->api_minor = sev->snp_plat_status.api_minor;
1300 sev->build = sev->snp_plat_status.build_id;
1301
1302 /*
1303 * Do feature discovery of the currently loaded firmware,
1304 * and cache feature information from CPUID 0x8000_0024,
1305 * sub-function 0.
1306 */
1307 if (!sev->snp_plat_status.feature_info)
1308 return 0;
1309
1310 /*
1311 * Use dynamically allocated structure for the SNP_FEATURE_INFO
1312 * command to ensure structure is 8-byte aligned, and does not
1313 * cross a page boundary.
1314 */
1315 page = alloc_page(GFP_KERNEL);
1316 if (!page)
1317 return -ENOMEM;
1318
1319 feat_info = page_address(page);
1320 snp_feat_info.length = sizeof(snp_feat_info);
1321 snp_feat_info.ecx_in = 0;
1322 snp_feat_info.feature_info_paddr = __psp_pa(feat_info);
1323
1324 rc = sev_do_cmd(SEV_CMD_SNP_FEATURE_INFO, &snp_feat_info, error);
1325 if (!rc)
1326 sev->snp_feat_info_0 = *feat_info;
1327 else
1328 dev_err(sev->dev, "SNP FEATURE_INFO command failed, ret = %d, error = %#x\n",
1329 rc, *error);
1330
1331 __free_page(page);
1332
1333 return rc;
1334 }
1335
snp_filter_reserved_mem_regions(struct resource * rs,void * arg)1336 static int snp_filter_reserved_mem_regions(struct resource *rs, void *arg)
1337 {
1338 struct sev_data_range_list *range_list = arg;
1339 struct sev_data_range *range = &range_list->ranges[range_list->num_elements];
1340 size_t size;
1341
1342 /*
1343 * Ensure the list of HV_FIXED pages that will be passed to firmware
1344 * do not exceed the page-sized argument buffer.
1345 */
1346 if ((range_list->num_elements * sizeof(struct sev_data_range) +
1347 sizeof(struct sev_data_range_list)) > PAGE_SIZE)
1348 return -E2BIG;
1349
1350 switch (rs->desc) {
1351 case E820_TYPE_RESERVED:
1352 case E820_TYPE_PMEM:
1353 case E820_TYPE_ACPI:
1354 range->base = rs->start & PAGE_MASK;
1355 size = PAGE_ALIGN((rs->end + 1) - rs->start);
1356 range->page_count = size >> PAGE_SHIFT;
1357 range_list->num_elements++;
1358 break;
1359 default:
1360 break;
1361 }
1362
1363 return 0;
1364 }
1365
__sev_snp_init_locked(int * error,unsigned int max_snp_asid)1366 static int __sev_snp_init_locked(int *error, unsigned int max_snp_asid)
1367 {
1368 struct psp_device *psp = psp_master;
1369 struct sev_data_snp_init_ex data;
1370 struct sev_device *sev;
1371 void *arg = &data;
1372 int cmd, rc = 0;
1373
1374 if (!cc_platform_has(CC_ATTR_HOST_SEV_SNP))
1375 return -ENODEV;
1376
1377 sev = psp->sev_data;
1378
1379 if (sev->snp_initialized)
1380 return 0;
1381
1382 if (!sev_version_greater_or_equal(SNP_MIN_API_MAJOR, SNP_MIN_API_MINOR)) {
1383 dev_dbg(sev->dev, "SEV-SNP support requires firmware version >= %d:%d\n",
1384 SNP_MIN_API_MAJOR, SNP_MIN_API_MINOR);
1385 return -EOPNOTSUPP;
1386 }
1387
1388 /* SNP_INIT requires MSR_VM_HSAVE_PA to be cleared on all CPUs. */
1389 on_each_cpu(snp_set_hsave_pa, NULL, 1);
1390
1391 /*
1392 * Starting in SNP firmware v1.52, the SNP_INIT_EX command takes a list
1393 * of system physical address ranges to convert into HV-fixed page
1394 * states during the RMP initialization. For instance, the memory that
1395 * UEFI reserves should be included in the that list. This allows system
1396 * components that occasionally write to memory (e.g. logging to UEFI
1397 * reserved regions) to not fail due to RMP initialization and SNP
1398 * enablement.
1399 *
1400 */
1401 if (sev_version_greater_or_equal(SNP_MIN_API_MAJOR, 52)) {
1402 /*
1403 * Firmware checks that the pages containing the ranges enumerated
1404 * in the RANGES structure are either in the default page state or in the
1405 * firmware page state.
1406 */
1407 snp_range_list = kzalloc(PAGE_SIZE, GFP_KERNEL);
1408 if (!snp_range_list) {
1409 dev_err(sev->dev,
1410 "SEV: SNP_INIT_EX range list memory allocation failed\n");
1411 return -ENOMEM;
1412 }
1413
1414 /*
1415 * Retrieve all reserved memory regions from the e820 memory map
1416 * to be setup as HV-fixed pages.
1417 */
1418 rc = walk_iomem_res_desc(IORES_DESC_NONE, IORESOURCE_MEM, 0, ~0,
1419 snp_range_list, snp_filter_reserved_mem_regions);
1420 if (rc) {
1421 dev_err(sev->dev,
1422 "SEV: SNP_INIT_EX walk_iomem_res_desc failed rc = %d\n", rc);
1423 return rc;
1424 }
1425
1426 /*
1427 * Add HV_Fixed pages from other PSP sub-devices, such as SFS to the
1428 * HV_Fixed page list.
1429 */
1430 snp_add_hv_fixed_pages(sev, snp_range_list);
1431
1432 memset(&data, 0, sizeof(data));
1433
1434 if (max_snp_asid) {
1435 data.ciphertext_hiding_en = 1;
1436 data.max_snp_asid = max_snp_asid;
1437 }
1438
1439 data.init_rmp = 1;
1440 data.list_paddr_en = 1;
1441 data.list_paddr = __psp_pa(snp_range_list);
1442 cmd = SEV_CMD_SNP_INIT_EX;
1443 } else {
1444 cmd = SEV_CMD_SNP_INIT;
1445 arg = NULL;
1446 }
1447
1448 /*
1449 * The following sequence must be issued before launching the first SNP
1450 * guest to ensure all dirty cache lines are flushed, including from
1451 * updates to the RMP table itself via the RMPUPDATE instruction:
1452 *
1453 * - WBINVD on all running CPUs
1454 * - SEV_CMD_SNP_INIT[_EX] firmware command
1455 * - WBINVD on all running CPUs
1456 * - SEV_CMD_SNP_DF_FLUSH firmware command
1457 */
1458 wbinvd_on_all_cpus();
1459
1460 rc = __sev_do_cmd_locked(cmd, arg, error);
1461 if (rc) {
1462 dev_err(sev->dev, "SEV-SNP: %s failed rc %d, error %#x\n",
1463 cmd == SEV_CMD_SNP_INIT_EX ? "SNP_INIT_EX" : "SNP_INIT",
1464 rc, *error);
1465 return rc;
1466 }
1467
1468 /* Prepare for first SNP guest launch after INIT. */
1469 wbinvd_on_all_cpus();
1470 rc = __sev_do_cmd_locked(SEV_CMD_SNP_DF_FLUSH, NULL, error);
1471 if (rc) {
1472 dev_err(sev->dev, "SEV-SNP: SNP_DF_FLUSH failed rc %d, error %#x\n",
1473 rc, *error);
1474 return rc;
1475 }
1476
1477 snp_hv_fixed_pages_state_update(sev, HV_FIXED);
1478 sev->snp_initialized = true;
1479 dev_dbg(sev->dev, "SEV-SNP firmware initialized\n");
1480
1481 dev_info(sev->dev, "SEV-SNP API:%d.%d build:%d\n", sev->api_major,
1482 sev->api_minor, sev->build);
1483
1484 atomic_notifier_chain_register(&panic_notifier_list,
1485 &snp_panic_notifier);
1486
1487 sev_es_tmr_size = SNP_TMR_SIZE;
1488
1489 return 0;
1490 }
1491
__sev_platform_init_handle_tmr(struct sev_device * sev)1492 static void __sev_platform_init_handle_tmr(struct sev_device *sev)
1493 {
1494 if (sev_es_tmr)
1495 return;
1496
1497 /* Obtain the TMR memory area for SEV-ES use */
1498 sev_es_tmr = sev_fw_alloc(sev_es_tmr_size);
1499 if (sev_es_tmr) {
1500 /* Must flush the cache before giving it to the firmware */
1501 if (!sev->snp_initialized)
1502 clflush_cache_range(sev_es_tmr, sev_es_tmr_size);
1503 } else {
1504 dev_warn(sev->dev, "SEV: TMR allocation failed, SEV-ES support unavailable\n");
1505 }
1506 }
1507
1508 /*
1509 * If an init_ex_path is provided allocate a buffer for the file and
1510 * read in the contents. Additionally, if SNP is initialized, convert
1511 * the buffer pages to firmware pages.
1512 */
__sev_platform_init_handle_init_ex_path(struct sev_device * sev)1513 static int __sev_platform_init_handle_init_ex_path(struct sev_device *sev)
1514 {
1515 struct page *page;
1516 int rc;
1517
1518 if (!init_ex_path)
1519 return 0;
1520
1521 if (sev_init_ex_buffer)
1522 return 0;
1523
1524 page = alloc_pages(GFP_KERNEL, get_order(NV_LENGTH));
1525 if (!page) {
1526 dev_err(sev->dev, "SEV: INIT_EX NV memory allocation failed\n");
1527 return -ENOMEM;
1528 }
1529
1530 sev_init_ex_buffer = page_address(page);
1531
1532 rc = sev_read_init_ex_file();
1533 if (rc)
1534 return rc;
1535
1536 /* If SEV-SNP is initialized, transition to firmware page. */
1537 if (sev->snp_initialized) {
1538 unsigned long npages;
1539
1540 npages = 1UL << get_order(NV_LENGTH);
1541 if (rmp_mark_pages_firmware(__pa(sev_init_ex_buffer), npages, false)) {
1542 dev_err(sev->dev, "SEV: INIT_EX NV memory page state change failed.\n");
1543 return -ENOMEM;
1544 }
1545 }
1546
1547 return 0;
1548 }
1549
__sev_platform_init_locked(int * error)1550 static int __sev_platform_init_locked(int *error)
1551 {
1552 int rc, psp_ret, dfflush_error;
1553 struct sev_device *sev;
1554
1555 psp_ret = dfflush_error = SEV_RET_NO_FW_CALL;
1556
1557 if (!psp_master || !psp_master->sev_data)
1558 return -ENODEV;
1559
1560 sev = psp_master->sev_data;
1561
1562 if (sev->sev_plat_status.state == SEV_STATE_INIT)
1563 return 0;
1564
1565 __sev_platform_init_handle_tmr(sev);
1566
1567 rc = __sev_platform_init_handle_init_ex_path(sev);
1568 if (rc)
1569 return rc;
1570
1571 rc = __sev_do_init_locked(&psp_ret);
1572 if (rc && psp_ret == SEV_RET_SECURE_DATA_INVALID) {
1573 /*
1574 * Initialization command returned an integrity check failure
1575 * status code, meaning that firmware load and validation of SEV
1576 * related persistent data has failed. Retrying the
1577 * initialization function should succeed by replacing the state
1578 * with a reset state.
1579 */
1580 dev_err(sev->dev,
1581 "SEV: retrying INIT command because of SECURE_DATA_INVALID error. Retrying once to reset PSP SEV state.");
1582 rc = __sev_do_init_locked(&psp_ret);
1583 }
1584
1585 if (error)
1586 *error = psp_ret;
1587
1588 if (rc) {
1589 dev_err(sev->dev, "SEV: %s failed %#x, rc %d\n",
1590 sev_init_ex_buffer ? "INIT_EX" : "INIT", psp_ret, rc);
1591 return rc;
1592 }
1593
1594 sev->sev_plat_status.state = SEV_STATE_INIT;
1595
1596 /* Prepare for first SEV guest launch after INIT */
1597 wbinvd_on_all_cpus();
1598 rc = __sev_do_cmd_locked(SEV_CMD_DF_FLUSH, NULL, &dfflush_error);
1599 if (rc) {
1600 dev_err(sev->dev, "SEV: DF_FLUSH failed %#x, rc %d\n",
1601 dfflush_error, rc);
1602 return rc;
1603 }
1604
1605 dev_dbg(sev->dev, "SEV firmware initialized\n");
1606
1607 dev_info(sev->dev, "SEV API:%d.%d build:%d\n", sev->api_major,
1608 sev->api_minor, sev->build);
1609
1610 return 0;
1611 }
1612
_sev_platform_init_locked(struct sev_platform_init_args * args)1613 static int _sev_platform_init_locked(struct sev_platform_init_args *args)
1614 {
1615 struct sev_device *sev;
1616 int rc;
1617
1618 if (!psp_master || !psp_master->sev_data)
1619 return -ENODEV;
1620
1621 /*
1622 * Skip SNP/SEV initialization under a kdump kernel as SEV/SNP
1623 * may already be initialized in the previous kernel. Since no
1624 * SNP/SEV guests are run under a kdump kernel, there is no
1625 * need to initialize SNP or SEV during kdump boot.
1626 */
1627 if (is_kdump_kernel())
1628 return 0;
1629
1630 sev = psp_master->sev_data;
1631
1632 if (sev->sev_plat_status.state == SEV_STATE_INIT)
1633 return 0;
1634
1635 rc = __sev_snp_init_locked(&args->error, args->max_snp_asid);
1636 if (rc && rc != -ENODEV)
1637 return rc;
1638
1639 /* Defer legacy SEV/SEV-ES support if allowed by caller/module. */
1640 if (args->probe && !psp_init_on_probe)
1641 return 0;
1642
1643 return __sev_platform_init_locked(&args->error);
1644 }
1645
sev_platform_init(struct sev_platform_init_args * args)1646 int sev_platform_init(struct sev_platform_init_args *args)
1647 {
1648 int rc;
1649
1650 mutex_lock(&sev_cmd_mutex);
1651 rc = _sev_platform_init_locked(args);
1652 mutex_unlock(&sev_cmd_mutex);
1653
1654 return rc;
1655 }
1656 EXPORT_SYMBOL_GPL(sev_platform_init);
1657
__sev_platform_shutdown_locked(int * error)1658 static int __sev_platform_shutdown_locked(int *error)
1659 {
1660 struct psp_device *psp = psp_master;
1661 struct sev_device *sev;
1662 int ret;
1663
1664 if (!psp || !psp->sev_data)
1665 return 0;
1666
1667 sev = psp->sev_data;
1668
1669 if (sev->sev_plat_status.state == SEV_STATE_UNINIT)
1670 return 0;
1671
1672 ret = __sev_do_cmd_locked(SEV_CMD_SHUTDOWN, NULL, error);
1673 if (ret) {
1674 dev_err(sev->dev, "SEV: failed to SHUTDOWN error %#x, rc %d\n",
1675 *error, ret);
1676 return ret;
1677 }
1678
1679 sev->sev_plat_status.state = SEV_STATE_UNINIT;
1680 dev_dbg(sev->dev, "SEV firmware shutdown\n");
1681
1682 return ret;
1683 }
1684
sev_get_platform_state(int * state,int * error)1685 static int sev_get_platform_state(int *state, int *error)
1686 {
1687 struct sev_user_data_status data;
1688 int rc;
1689
1690 rc = __sev_do_cmd_locked(SEV_CMD_PLATFORM_STATUS, &data, error);
1691 if (rc)
1692 return rc;
1693
1694 *state = data.state;
1695 return rc;
1696 }
1697
sev_move_to_init_state(struct sev_issue_cmd * argp,bool * shutdown_required)1698 static int sev_move_to_init_state(struct sev_issue_cmd *argp, bool *shutdown_required)
1699 {
1700 struct sev_platform_init_args init_args = {0};
1701 int rc;
1702
1703 rc = _sev_platform_init_locked(&init_args);
1704 if (rc) {
1705 argp->error = SEV_RET_INVALID_PLATFORM_STATE;
1706 return rc;
1707 }
1708
1709 *shutdown_required = true;
1710
1711 return 0;
1712 }
1713
snp_move_to_init_state(struct sev_issue_cmd * argp,bool * shutdown_required)1714 static int snp_move_to_init_state(struct sev_issue_cmd *argp, bool *shutdown_required)
1715 {
1716 int error, rc;
1717
1718 rc = __sev_snp_init_locked(&error, 0);
1719 if (rc) {
1720 argp->error = SEV_RET_INVALID_PLATFORM_STATE;
1721 return rc;
1722 }
1723
1724 *shutdown_required = true;
1725
1726 return 0;
1727 }
1728
sev_ioctl_do_reset(struct sev_issue_cmd * argp,bool writable)1729 static int sev_ioctl_do_reset(struct sev_issue_cmd *argp, bool writable)
1730 {
1731 int state, rc;
1732
1733 if (!writable)
1734 return -EPERM;
1735
1736 /*
1737 * The SEV spec requires that FACTORY_RESET must be issued in
1738 * UNINIT state. Before we go further lets check if any guest is
1739 * active.
1740 *
1741 * If FW is in WORKING state then deny the request otherwise issue
1742 * SHUTDOWN command do INIT -> UNINIT before issuing the FACTORY_RESET.
1743 *
1744 */
1745 rc = sev_get_platform_state(&state, &argp->error);
1746 if (rc)
1747 return rc;
1748
1749 if (state == SEV_STATE_WORKING)
1750 return -EBUSY;
1751
1752 if (state == SEV_STATE_INIT) {
1753 rc = __sev_platform_shutdown_locked(&argp->error);
1754 if (rc)
1755 return rc;
1756 }
1757
1758 return __sev_do_cmd_locked(SEV_CMD_FACTORY_RESET, NULL, &argp->error);
1759 }
1760
sev_ioctl_do_platform_status(struct sev_issue_cmd * argp)1761 static int sev_ioctl_do_platform_status(struct sev_issue_cmd *argp)
1762 {
1763 struct sev_user_data_status data;
1764 int ret;
1765
1766 memset(&data, 0, sizeof(data));
1767
1768 ret = __sev_do_cmd_locked(SEV_CMD_PLATFORM_STATUS, &data, &argp->error);
1769 if (ret)
1770 return ret;
1771
1772 if (copy_to_user((void __user *)argp->data, &data, sizeof(data)))
1773 ret = -EFAULT;
1774
1775 return ret;
1776 }
1777
sev_ioctl_do_pek_pdh_gen(int cmd,struct sev_issue_cmd * argp,bool writable)1778 static int sev_ioctl_do_pek_pdh_gen(int cmd, struct sev_issue_cmd *argp, bool writable)
1779 {
1780 struct sev_device *sev = psp_master->sev_data;
1781 bool shutdown_required = false;
1782 int rc;
1783
1784 if (!writable)
1785 return -EPERM;
1786
1787 if (sev->sev_plat_status.state == SEV_STATE_UNINIT) {
1788 rc = sev_move_to_init_state(argp, &shutdown_required);
1789 if (rc)
1790 return rc;
1791 }
1792
1793 rc = __sev_do_cmd_locked(cmd, NULL, &argp->error);
1794
1795 if (shutdown_required)
1796 __sev_firmware_shutdown(sev, false);
1797
1798 return rc;
1799 }
1800
sev_ioctl_do_pek_csr(struct sev_issue_cmd * argp,bool writable)1801 static int sev_ioctl_do_pek_csr(struct sev_issue_cmd *argp, bool writable)
1802 {
1803 struct sev_device *sev = psp_master->sev_data;
1804 struct sev_user_data_pek_csr input;
1805 bool shutdown_required = false;
1806 struct sev_data_pek_csr data;
1807 void __user *input_address;
1808 void *blob = NULL;
1809 int ret;
1810
1811 if (!writable)
1812 return -EPERM;
1813
1814 if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
1815 return -EFAULT;
1816
1817 memset(&data, 0, sizeof(data));
1818
1819 /* userspace wants to query CSR length */
1820 if (!input.address || !input.length)
1821 goto cmd;
1822
1823 /* allocate a physically contiguous buffer to store the CSR blob */
1824 input_address = (void __user *)input.address;
1825 if (input.length > SEV_FW_BLOB_MAX_SIZE)
1826 return -EFAULT;
1827
1828 blob = kzalloc(input.length, GFP_KERNEL);
1829 if (!blob)
1830 return -ENOMEM;
1831
1832 data.address = __psp_pa(blob);
1833 data.len = input.length;
1834
1835 cmd:
1836 if (sev->sev_plat_status.state == SEV_STATE_UNINIT) {
1837 ret = sev_move_to_init_state(argp, &shutdown_required);
1838 if (ret)
1839 goto e_free_blob;
1840 }
1841
1842 ret = __sev_do_cmd_locked(SEV_CMD_PEK_CSR, &data, &argp->error);
1843
1844 /* If we query the CSR length, FW responded with expected data. */
1845 input.length = data.len;
1846
1847 if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) {
1848 ret = -EFAULT;
1849 goto e_free_blob;
1850 }
1851
1852 if (blob) {
1853 if (copy_to_user(input_address, blob, input.length))
1854 ret = -EFAULT;
1855 }
1856
1857 e_free_blob:
1858 if (shutdown_required)
1859 __sev_firmware_shutdown(sev, false);
1860
1861 kfree(blob);
1862 return ret;
1863 }
1864
psp_copy_user_blob(u64 uaddr,u32 len)1865 void *psp_copy_user_blob(u64 uaddr, u32 len)
1866 {
1867 if (!uaddr || !len)
1868 return ERR_PTR(-EINVAL);
1869
1870 /* verify that blob length does not exceed our limit */
1871 if (len > SEV_FW_BLOB_MAX_SIZE)
1872 return ERR_PTR(-EINVAL);
1873
1874 return memdup_user((void __user *)uaddr, len);
1875 }
1876 EXPORT_SYMBOL_GPL(psp_copy_user_blob);
1877
sev_get_api_version(void)1878 static int sev_get_api_version(void)
1879 {
1880 struct sev_device *sev = psp_master->sev_data;
1881 struct sev_user_data_status status;
1882 int error = 0, ret;
1883
1884 /*
1885 * Cache SNP platform status and SNP feature information
1886 * if SNP is available.
1887 */
1888 if (cc_platform_has(CC_ATTR_HOST_SEV_SNP)) {
1889 ret = snp_get_platform_data(sev, &error);
1890 if (ret)
1891 return 1;
1892 }
1893
1894 ret = sev_platform_status(&status, &error);
1895 if (ret) {
1896 dev_err(sev->dev,
1897 "SEV: failed to get status. Error: %#x\n", error);
1898 return 1;
1899 }
1900
1901 /* Cache SEV platform status */
1902 sev->sev_plat_status = status;
1903
1904 sev->api_major = status.api_major;
1905 sev->api_minor = status.api_minor;
1906 sev->build = status.build;
1907
1908 return 0;
1909 }
1910
sev_get_firmware(struct device * dev,const struct firmware ** firmware)1911 static int sev_get_firmware(struct device *dev,
1912 const struct firmware **firmware)
1913 {
1914 char fw_name_specific[SEV_FW_NAME_SIZE];
1915 char fw_name_subset[SEV_FW_NAME_SIZE];
1916
1917 snprintf(fw_name_specific, sizeof(fw_name_specific),
1918 "amd/amd_sev_fam%.2xh_model%.2xh.sbin",
1919 boot_cpu_data.x86, boot_cpu_data.x86_model);
1920
1921 snprintf(fw_name_subset, sizeof(fw_name_subset),
1922 "amd/amd_sev_fam%.2xh_model%.1xxh.sbin",
1923 boot_cpu_data.x86, (boot_cpu_data.x86_model & 0xf0) >> 4);
1924
1925 /* Check for SEV FW for a particular model.
1926 * Ex. amd_sev_fam17h_model00h.sbin for Family 17h Model 00h
1927 *
1928 * or
1929 *
1930 * Check for SEV FW common to a subset of models.
1931 * Ex. amd_sev_fam17h_model0xh.sbin for
1932 * Family 17h Model 00h -- Family 17h Model 0Fh
1933 *
1934 * or
1935 *
1936 * Fall-back to using generic name: sev.fw
1937 */
1938 if ((firmware_request_nowarn(firmware, fw_name_specific, dev) >= 0) ||
1939 (firmware_request_nowarn(firmware, fw_name_subset, dev) >= 0) ||
1940 (firmware_request_nowarn(firmware, SEV_FW_FILE, dev) >= 0))
1941 return 0;
1942
1943 return -ENOENT;
1944 }
1945
1946 /* Don't fail if SEV FW couldn't be updated. Continue with existing SEV FW */
sev_update_firmware(struct device * dev)1947 static int sev_update_firmware(struct device *dev)
1948 {
1949 struct sev_data_download_firmware *data;
1950 const struct firmware *firmware;
1951 int ret, error, order;
1952 struct page *p;
1953 u64 data_size;
1954
1955 if (!sev_version_greater_or_equal(0, 15)) {
1956 dev_dbg(dev, "DOWNLOAD_FIRMWARE not supported\n");
1957 return -1;
1958 }
1959
1960 if (sev_get_firmware(dev, &firmware) == -ENOENT) {
1961 dev_dbg(dev, "No SEV firmware file present\n");
1962 return -1;
1963 }
1964
1965 /*
1966 * SEV FW expects the physical address given to it to be 32
1967 * byte aligned. Memory allocated has structure placed at the
1968 * beginning followed by the firmware being passed to the SEV
1969 * FW. Allocate enough memory for data structure + alignment
1970 * padding + SEV FW.
1971 */
1972 data_size = ALIGN(sizeof(struct sev_data_download_firmware), 32);
1973
1974 order = get_order(firmware->size + data_size);
1975 p = alloc_pages(GFP_KERNEL, order);
1976 if (!p) {
1977 ret = -1;
1978 goto fw_err;
1979 }
1980
1981 /*
1982 * Copy firmware data to a kernel allocated contiguous
1983 * memory region.
1984 */
1985 data = page_address(p);
1986 memcpy(page_address(p) + data_size, firmware->data, firmware->size);
1987
1988 data->address = __psp_pa(page_address(p) + data_size);
1989 data->len = firmware->size;
1990
1991 ret = sev_do_cmd(SEV_CMD_DOWNLOAD_FIRMWARE, data, &error);
1992
1993 /*
1994 * A quirk for fixing the committed TCB version, when upgrading from
1995 * earlier firmware version than 1.50.
1996 */
1997 if (!ret && !sev_version_greater_or_equal(1, 50))
1998 ret = sev_do_cmd(SEV_CMD_DOWNLOAD_FIRMWARE, data, &error);
1999
2000 if (ret)
2001 dev_dbg(dev, "Failed to update SEV firmware: %#x\n", error);
2002
2003 __free_pages(p, order);
2004
2005 fw_err:
2006 release_firmware(firmware);
2007
2008 return ret;
2009 }
2010
__sev_snp_shutdown_locked(int * error,bool panic)2011 static int __sev_snp_shutdown_locked(int *error, bool panic)
2012 {
2013 struct psp_device *psp = psp_master;
2014 struct sev_device *sev;
2015 struct sev_data_snp_shutdown_ex data;
2016 int ret;
2017
2018 if (!psp || !psp->sev_data)
2019 return 0;
2020
2021 sev = psp->sev_data;
2022
2023 if (!sev->snp_initialized)
2024 return 0;
2025
2026 memset(&data, 0, sizeof(data));
2027 data.len = sizeof(data);
2028 data.iommu_snp_shutdown = 1;
2029
2030 /*
2031 * If invoked during panic handling, local interrupts are disabled
2032 * and all CPUs are stopped, so wbinvd_on_all_cpus() can't be called.
2033 * In that case, a wbinvd() is done on remote CPUs via the NMI
2034 * callback, so only a local wbinvd() is needed here.
2035 */
2036 if (!panic)
2037 wbinvd_on_all_cpus();
2038 else
2039 wbinvd();
2040
2041 ret = __sev_do_cmd_locked(SEV_CMD_SNP_SHUTDOWN_EX, &data, error);
2042 /* SHUTDOWN may require DF_FLUSH */
2043 if (*error == SEV_RET_DFFLUSH_REQUIRED) {
2044 int dfflush_error = SEV_RET_NO_FW_CALL;
2045
2046 ret = __sev_do_cmd_locked(SEV_CMD_SNP_DF_FLUSH, NULL, &dfflush_error);
2047 if (ret) {
2048 dev_err(sev->dev, "SEV-SNP DF_FLUSH failed, ret = %d, error = %#x\n",
2049 ret, dfflush_error);
2050 return ret;
2051 }
2052 /* reissue the shutdown command */
2053 ret = __sev_do_cmd_locked(SEV_CMD_SNP_SHUTDOWN_EX, &data,
2054 error);
2055 }
2056 if (ret) {
2057 dev_err(sev->dev, "SEV-SNP firmware shutdown failed, rc %d, error %#x\n",
2058 ret, *error);
2059 return ret;
2060 }
2061
2062 /*
2063 * SNP_SHUTDOWN_EX with IOMMU_SNP_SHUTDOWN set to 1 disables SNP
2064 * enforcement by the IOMMU and also transitions all pages
2065 * associated with the IOMMU to the Reclaim state.
2066 * Firmware was transitioning the IOMMU pages to Hypervisor state
2067 * before version 1.53. But, accounting for the number of assigned
2068 * 4kB pages in a 2M page was done incorrectly by not transitioning
2069 * to the Reclaim state. This resulted in RMP #PF when later accessing
2070 * the 2M page containing those pages during kexec boot. Hence, the
2071 * firmware now transitions these pages to Reclaim state and hypervisor
2072 * needs to transition these pages to shared state. SNP Firmware
2073 * version 1.53 and above are needed for kexec boot.
2074 */
2075 ret = amd_iommu_snp_disable();
2076 if (ret) {
2077 dev_err(sev->dev, "SNP IOMMU shutdown failed\n");
2078 return ret;
2079 }
2080
2081 snp_leak_hv_fixed_pages();
2082 sev->snp_initialized = false;
2083 dev_dbg(sev->dev, "SEV-SNP firmware shutdown\n");
2084
2085 /*
2086 * __sev_snp_shutdown_locked() deadlocks when it tries to unregister
2087 * itself during panic as the panic notifier is called with RCU read
2088 * lock held and notifier unregistration does RCU synchronization.
2089 */
2090 if (!panic)
2091 atomic_notifier_chain_unregister(&panic_notifier_list,
2092 &snp_panic_notifier);
2093
2094 /* Reset TMR size back to default */
2095 sev_es_tmr_size = SEV_TMR_SIZE;
2096
2097 return ret;
2098 }
2099
sev_ioctl_do_pek_import(struct sev_issue_cmd * argp,bool writable)2100 static int sev_ioctl_do_pek_import(struct sev_issue_cmd *argp, bool writable)
2101 {
2102 struct sev_device *sev = psp_master->sev_data;
2103 struct sev_user_data_pek_cert_import input;
2104 struct sev_data_pek_cert_import data;
2105 bool shutdown_required = false;
2106 void *pek_blob, *oca_blob;
2107 int ret;
2108
2109 if (!writable)
2110 return -EPERM;
2111
2112 if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
2113 return -EFAULT;
2114
2115 /* copy PEK certificate blobs from userspace */
2116 pek_blob = psp_copy_user_blob(input.pek_cert_address, input.pek_cert_len);
2117 if (IS_ERR(pek_blob))
2118 return PTR_ERR(pek_blob);
2119
2120 data.reserved = 0;
2121 data.pek_cert_address = __psp_pa(pek_blob);
2122 data.pek_cert_len = input.pek_cert_len;
2123
2124 /* copy PEK certificate blobs from userspace */
2125 oca_blob = psp_copy_user_blob(input.oca_cert_address, input.oca_cert_len);
2126 if (IS_ERR(oca_blob)) {
2127 ret = PTR_ERR(oca_blob);
2128 goto e_free_pek;
2129 }
2130
2131 data.oca_cert_address = __psp_pa(oca_blob);
2132 data.oca_cert_len = input.oca_cert_len;
2133
2134 /* If platform is not in INIT state then transition it to INIT */
2135 if (sev->sev_plat_status.state != SEV_STATE_INIT) {
2136 ret = sev_move_to_init_state(argp, &shutdown_required);
2137 if (ret)
2138 goto e_free_oca;
2139 }
2140
2141 ret = __sev_do_cmd_locked(SEV_CMD_PEK_CERT_IMPORT, &data, &argp->error);
2142
2143 e_free_oca:
2144 if (shutdown_required)
2145 __sev_firmware_shutdown(sev, false);
2146
2147 kfree(oca_blob);
2148 e_free_pek:
2149 kfree(pek_blob);
2150 return ret;
2151 }
2152
sev_ioctl_do_get_id2(struct sev_issue_cmd * argp)2153 static int sev_ioctl_do_get_id2(struct sev_issue_cmd *argp)
2154 {
2155 struct sev_user_data_get_id2 input;
2156 struct sev_data_get_id data;
2157 void __user *input_address;
2158 void *id_blob = NULL;
2159 int ret;
2160
2161 /* SEV GET_ID is available from SEV API v0.16 and up */
2162 if (!sev_version_greater_or_equal(0, 16))
2163 return -ENOTSUPP;
2164
2165 if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
2166 return -EFAULT;
2167
2168 input_address = (void __user *)input.address;
2169
2170 if (input.address && input.length) {
2171 /*
2172 * The length of the ID shouldn't be assumed by software since
2173 * it may change in the future. The allocation size is limited
2174 * to 1 << (PAGE_SHIFT + MAX_PAGE_ORDER) by the page allocator.
2175 * If the allocation fails, simply return ENOMEM rather than
2176 * warning in the kernel log.
2177 */
2178 id_blob = kzalloc(input.length, GFP_KERNEL | __GFP_NOWARN);
2179 if (!id_blob)
2180 return -ENOMEM;
2181
2182 data.address = __psp_pa(id_blob);
2183 data.len = input.length;
2184 } else {
2185 data.address = 0;
2186 data.len = 0;
2187 }
2188
2189 ret = __sev_do_cmd_locked(SEV_CMD_GET_ID, &data, &argp->error);
2190
2191 /*
2192 * Firmware will return the length of the ID value (either the minimum
2193 * required length or the actual length written), return it to the user.
2194 */
2195 input.length = data.len;
2196
2197 if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) {
2198 ret = -EFAULT;
2199 goto e_free;
2200 }
2201
2202 if (id_blob) {
2203 if (copy_to_user(input_address, id_blob, data.len)) {
2204 ret = -EFAULT;
2205 goto e_free;
2206 }
2207 }
2208
2209 e_free:
2210 kfree(id_blob);
2211
2212 return ret;
2213 }
2214
sev_ioctl_do_get_id(struct sev_issue_cmd * argp)2215 static int sev_ioctl_do_get_id(struct sev_issue_cmd *argp)
2216 {
2217 struct sev_data_get_id *data;
2218 u64 data_size, user_size;
2219 void *id_blob, *mem;
2220 int ret;
2221
2222 /* SEV GET_ID available from SEV API v0.16 and up */
2223 if (!sev_version_greater_or_equal(0, 16))
2224 return -ENOTSUPP;
2225
2226 /* SEV FW expects the buffer it fills with the ID to be
2227 * 8-byte aligned. Memory allocated should be enough to
2228 * hold data structure + alignment padding + memory
2229 * where SEV FW writes the ID.
2230 */
2231 data_size = ALIGN(sizeof(struct sev_data_get_id), 8);
2232 user_size = sizeof(struct sev_user_data_get_id);
2233
2234 mem = kzalloc(data_size + user_size, GFP_KERNEL);
2235 if (!mem)
2236 return -ENOMEM;
2237
2238 data = mem;
2239 id_blob = mem + data_size;
2240
2241 data->address = __psp_pa(id_blob);
2242 data->len = user_size;
2243
2244 ret = __sev_do_cmd_locked(SEV_CMD_GET_ID, data, &argp->error);
2245 if (!ret) {
2246 if (copy_to_user((void __user *)argp->data, id_blob, data->len))
2247 ret = -EFAULT;
2248 }
2249
2250 kfree(mem);
2251
2252 return ret;
2253 }
2254
sev_ioctl_do_pdh_export(struct sev_issue_cmd * argp,bool writable)2255 static int sev_ioctl_do_pdh_export(struct sev_issue_cmd *argp, bool writable)
2256 {
2257 struct sev_device *sev = psp_master->sev_data;
2258 struct sev_user_data_pdh_cert_export input;
2259 void *pdh_blob = NULL, *cert_blob = NULL;
2260 struct sev_data_pdh_cert_export data;
2261 void __user *input_cert_chain_address;
2262 void __user *input_pdh_cert_address;
2263 bool shutdown_required = false;
2264 int ret;
2265
2266 if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
2267 return -EFAULT;
2268
2269 memset(&data, 0, sizeof(data));
2270
2271 input_pdh_cert_address = (void __user *)input.pdh_cert_address;
2272 input_cert_chain_address = (void __user *)input.cert_chain_address;
2273
2274 /* Userspace wants to query the certificate length. */
2275 if (!input.pdh_cert_address ||
2276 !input.pdh_cert_len ||
2277 !input.cert_chain_address)
2278 goto cmd;
2279
2280 /* Allocate a physically contiguous buffer to store the PDH blob. */
2281 if (input.pdh_cert_len > SEV_FW_BLOB_MAX_SIZE)
2282 return -EFAULT;
2283
2284 /* Allocate a physically contiguous buffer to store the cert chain blob. */
2285 if (input.cert_chain_len > SEV_FW_BLOB_MAX_SIZE)
2286 return -EFAULT;
2287
2288 pdh_blob = kzalloc(input.pdh_cert_len, GFP_KERNEL);
2289 if (!pdh_blob)
2290 return -ENOMEM;
2291
2292 data.pdh_cert_address = __psp_pa(pdh_blob);
2293 data.pdh_cert_len = input.pdh_cert_len;
2294
2295 cert_blob = kzalloc(input.cert_chain_len, GFP_KERNEL);
2296 if (!cert_blob) {
2297 ret = -ENOMEM;
2298 goto e_free_pdh;
2299 }
2300
2301 data.cert_chain_address = __psp_pa(cert_blob);
2302 data.cert_chain_len = input.cert_chain_len;
2303
2304 cmd:
2305 /* If platform is not in INIT state then transition it to INIT. */
2306 if (sev->sev_plat_status.state != SEV_STATE_INIT) {
2307 if (!writable) {
2308 ret = -EPERM;
2309 goto e_free_cert;
2310 }
2311 ret = sev_move_to_init_state(argp, &shutdown_required);
2312 if (ret)
2313 goto e_free_cert;
2314 }
2315
2316 ret = __sev_do_cmd_locked(SEV_CMD_PDH_CERT_EXPORT, &data, &argp->error);
2317
2318 /* If we query the length, FW responded with expected data. */
2319 input.cert_chain_len = data.cert_chain_len;
2320 input.pdh_cert_len = data.pdh_cert_len;
2321
2322 if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) {
2323 ret = -EFAULT;
2324 goto e_free_cert;
2325 }
2326
2327 if (pdh_blob) {
2328 if (copy_to_user(input_pdh_cert_address,
2329 pdh_blob, input.pdh_cert_len)) {
2330 ret = -EFAULT;
2331 goto e_free_cert;
2332 }
2333 }
2334
2335 if (cert_blob) {
2336 if (copy_to_user(input_cert_chain_address,
2337 cert_blob, input.cert_chain_len))
2338 ret = -EFAULT;
2339 }
2340
2341 e_free_cert:
2342 if (shutdown_required)
2343 __sev_firmware_shutdown(sev, false);
2344
2345 kfree(cert_blob);
2346 e_free_pdh:
2347 kfree(pdh_blob);
2348 return ret;
2349 }
2350
sev_ioctl_do_snp_platform_status(struct sev_issue_cmd * argp)2351 static int sev_ioctl_do_snp_platform_status(struct sev_issue_cmd *argp)
2352 {
2353 struct sev_device *sev = psp_master->sev_data;
2354 bool shutdown_required = false;
2355 struct sev_data_snp_addr buf;
2356 struct page *status_page;
2357 int ret, error;
2358 void *data;
2359
2360 if (!argp->data)
2361 return -EINVAL;
2362
2363 status_page = alloc_page(GFP_KERNEL_ACCOUNT);
2364 if (!status_page)
2365 return -ENOMEM;
2366
2367 data = page_address(status_page);
2368
2369 if (!sev->snp_initialized) {
2370 ret = snp_move_to_init_state(argp, &shutdown_required);
2371 if (ret)
2372 goto cleanup;
2373 }
2374
2375 /*
2376 * Firmware expects status page to be in firmware-owned state, otherwise
2377 * it will report firmware error code INVALID_PAGE_STATE (0x1A).
2378 */
2379 if (rmp_mark_pages_firmware(__pa(data), 1, true)) {
2380 ret = -EFAULT;
2381 goto cleanup;
2382 }
2383
2384 buf.address = __psp_pa(data);
2385 ret = __sev_do_cmd_locked(SEV_CMD_SNP_PLATFORM_STATUS, &buf, &argp->error);
2386
2387 /*
2388 * Status page will be transitioned to Reclaim state upon success, or
2389 * left in Firmware state in failure. Use snp_reclaim_pages() to
2390 * transition either case back to Hypervisor-owned state.
2391 */
2392 if (snp_reclaim_pages(__pa(data), 1, true))
2393 return -EFAULT;
2394
2395 if (ret)
2396 goto cleanup;
2397
2398 if (copy_to_user((void __user *)argp->data, data,
2399 sizeof(struct sev_user_data_snp_status)))
2400 ret = -EFAULT;
2401
2402 cleanup:
2403 if (shutdown_required)
2404 __sev_snp_shutdown_locked(&error, false);
2405
2406 __free_pages(status_page, 0);
2407 return ret;
2408 }
2409
sev_ioctl_do_snp_commit(struct sev_issue_cmd * argp)2410 static int sev_ioctl_do_snp_commit(struct sev_issue_cmd *argp)
2411 {
2412 struct sev_device *sev = psp_master->sev_data;
2413 struct sev_data_snp_commit buf;
2414 bool shutdown_required = false;
2415 int ret, error;
2416
2417 if (!sev->snp_initialized) {
2418 ret = snp_move_to_init_state(argp, &shutdown_required);
2419 if (ret)
2420 return ret;
2421 }
2422
2423 buf.len = sizeof(buf);
2424
2425 ret = __sev_do_cmd_locked(SEV_CMD_SNP_COMMIT, &buf, &argp->error);
2426
2427 if (shutdown_required)
2428 __sev_snp_shutdown_locked(&error, false);
2429
2430 return ret;
2431 }
2432
sev_ioctl_do_snp_set_config(struct sev_issue_cmd * argp,bool writable)2433 static int sev_ioctl_do_snp_set_config(struct sev_issue_cmd *argp, bool writable)
2434 {
2435 struct sev_device *sev = psp_master->sev_data;
2436 struct sev_user_data_snp_config config;
2437 bool shutdown_required = false;
2438 int ret, error;
2439
2440 if (!argp->data)
2441 return -EINVAL;
2442
2443 if (!writable)
2444 return -EPERM;
2445
2446 if (copy_from_user(&config, (void __user *)argp->data, sizeof(config)))
2447 return -EFAULT;
2448
2449 if (!sev->snp_initialized) {
2450 ret = snp_move_to_init_state(argp, &shutdown_required);
2451 if (ret)
2452 return ret;
2453 }
2454
2455 ret = __sev_do_cmd_locked(SEV_CMD_SNP_CONFIG, &config, &argp->error);
2456
2457 if (shutdown_required)
2458 __sev_snp_shutdown_locked(&error, false);
2459
2460 return ret;
2461 }
2462
sev_ioctl_do_snp_vlek_load(struct sev_issue_cmd * argp,bool writable)2463 static int sev_ioctl_do_snp_vlek_load(struct sev_issue_cmd *argp, bool writable)
2464 {
2465 struct sev_device *sev = psp_master->sev_data;
2466 struct sev_user_data_snp_vlek_load input;
2467 bool shutdown_required = false;
2468 int ret, error;
2469 void *blob;
2470
2471 if (!argp->data)
2472 return -EINVAL;
2473
2474 if (!writable)
2475 return -EPERM;
2476
2477 if (copy_from_user(&input, u64_to_user_ptr(argp->data), sizeof(input)))
2478 return -EFAULT;
2479
2480 if (input.len != sizeof(input) || input.vlek_wrapped_version != 0)
2481 return -EINVAL;
2482
2483 blob = psp_copy_user_blob(input.vlek_wrapped_address,
2484 sizeof(struct sev_user_data_snp_wrapped_vlek_hashstick));
2485 if (IS_ERR(blob))
2486 return PTR_ERR(blob);
2487
2488 input.vlek_wrapped_address = __psp_pa(blob);
2489
2490 if (!sev->snp_initialized) {
2491 ret = snp_move_to_init_state(argp, &shutdown_required);
2492 if (ret)
2493 goto cleanup;
2494 }
2495
2496 ret = __sev_do_cmd_locked(SEV_CMD_SNP_VLEK_LOAD, &input, &argp->error);
2497
2498 if (shutdown_required)
2499 __sev_snp_shutdown_locked(&error, false);
2500
2501 cleanup:
2502 kfree(blob);
2503
2504 return ret;
2505 }
2506
sev_ioctl(struct file * file,unsigned int ioctl,unsigned long arg)2507 static long sev_ioctl(struct file *file, unsigned int ioctl, unsigned long arg)
2508 {
2509 void __user *argp = (void __user *)arg;
2510 struct sev_issue_cmd input;
2511 int ret = -EFAULT;
2512 bool writable = file->f_mode & FMODE_WRITE;
2513
2514 if (!psp_master || !psp_master->sev_data)
2515 return -ENODEV;
2516
2517 if (ioctl != SEV_ISSUE_CMD)
2518 return -EINVAL;
2519
2520 if (copy_from_user(&input, argp, sizeof(struct sev_issue_cmd)))
2521 return -EFAULT;
2522
2523 if (input.cmd > SEV_MAX)
2524 return -EINVAL;
2525
2526 mutex_lock(&sev_cmd_mutex);
2527
2528 switch (input.cmd) {
2529
2530 case SEV_FACTORY_RESET:
2531 ret = sev_ioctl_do_reset(&input, writable);
2532 break;
2533 case SEV_PLATFORM_STATUS:
2534 ret = sev_ioctl_do_platform_status(&input);
2535 break;
2536 case SEV_PEK_GEN:
2537 ret = sev_ioctl_do_pek_pdh_gen(SEV_CMD_PEK_GEN, &input, writable);
2538 break;
2539 case SEV_PDH_GEN:
2540 ret = sev_ioctl_do_pek_pdh_gen(SEV_CMD_PDH_GEN, &input, writable);
2541 break;
2542 case SEV_PEK_CSR:
2543 ret = sev_ioctl_do_pek_csr(&input, writable);
2544 break;
2545 case SEV_PEK_CERT_IMPORT:
2546 ret = sev_ioctl_do_pek_import(&input, writable);
2547 break;
2548 case SEV_PDH_CERT_EXPORT:
2549 ret = sev_ioctl_do_pdh_export(&input, writable);
2550 break;
2551 case SEV_GET_ID:
2552 pr_warn_once("SEV_GET_ID command is deprecated, use SEV_GET_ID2\n");
2553 ret = sev_ioctl_do_get_id(&input);
2554 break;
2555 case SEV_GET_ID2:
2556 ret = sev_ioctl_do_get_id2(&input);
2557 break;
2558 case SNP_PLATFORM_STATUS:
2559 ret = sev_ioctl_do_snp_platform_status(&input);
2560 break;
2561 case SNP_COMMIT:
2562 ret = sev_ioctl_do_snp_commit(&input);
2563 break;
2564 case SNP_SET_CONFIG:
2565 ret = sev_ioctl_do_snp_set_config(&input, writable);
2566 break;
2567 case SNP_VLEK_LOAD:
2568 ret = sev_ioctl_do_snp_vlek_load(&input, writable);
2569 break;
2570 default:
2571 ret = -EINVAL;
2572 goto out;
2573 }
2574
2575 if (copy_to_user(argp, &input, sizeof(struct sev_issue_cmd)))
2576 ret = -EFAULT;
2577 out:
2578 mutex_unlock(&sev_cmd_mutex);
2579
2580 return ret;
2581 }
2582
2583 static const struct file_operations sev_fops = {
2584 .owner = THIS_MODULE,
2585 .unlocked_ioctl = sev_ioctl,
2586 };
2587
sev_platform_status(struct sev_user_data_status * data,int * error)2588 int sev_platform_status(struct sev_user_data_status *data, int *error)
2589 {
2590 return sev_do_cmd(SEV_CMD_PLATFORM_STATUS, data, error);
2591 }
2592 EXPORT_SYMBOL_GPL(sev_platform_status);
2593
sev_guest_deactivate(struct sev_data_deactivate * data,int * error)2594 int sev_guest_deactivate(struct sev_data_deactivate *data, int *error)
2595 {
2596 return sev_do_cmd(SEV_CMD_DEACTIVATE, data, error);
2597 }
2598 EXPORT_SYMBOL_GPL(sev_guest_deactivate);
2599
sev_guest_activate(struct sev_data_activate * data,int * error)2600 int sev_guest_activate(struct sev_data_activate *data, int *error)
2601 {
2602 return sev_do_cmd(SEV_CMD_ACTIVATE, data, error);
2603 }
2604 EXPORT_SYMBOL_GPL(sev_guest_activate);
2605
sev_guest_decommission(struct sev_data_decommission * data,int * error)2606 int sev_guest_decommission(struct sev_data_decommission *data, int *error)
2607 {
2608 return sev_do_cmd(SEV_CMD_DECOMMISSION, data, error);
2609 }
2610 EXPORT_SYMBOL_GPL(sev_guest_decommission);
2611
sev_guest_df_flush(int * error)2612 int sev_guest_df_flush(int *error)
2613 {
2614 return sev_do_cmd(SEV_CMD_DF_FLUSH, NULL, error);
2615 }
2616 EXPORT_SYMBOL_GPL(sev_guest_df_flush);
2617
sev_exit(struct kref * ref)2618 static void sev_exit(struct kref *ref)
2619 {
2620 misc_deregister(&misc_dev->misc);
2621 kfree(misc_dev);
2622 misc_dev = NULL;
2623 }
2624
sev_misc_init(struct sev_device * sev)2625 static int sev_misc_init(struct sev_device *sev)
2626 {
2627 struct device *dev = sev->dev;
2628 int ret;
2629
2630 /*
2631 * SEV feature support can be detected on multiple devices but the SEV
2632 * FW commands must be issued on the master. During probe, we do not
2633 * know the master hence we create /dev/sev on the first device probe.
2634 * sev_do_cmd() finds the right master device to which to issue the
2635 * command to the firmware.
2636 */
2637 if (!misc_dev) {
2638 struct miscdevice *misc;
2639
2640 misc_dev = kzalloc(sizeof(*misc_dev), GFP_KERNEL);
2641 if (!misc_dev)
2642 return -ENOMEM;
2643
2644 misc = &misc_dev->misc;
2645 misc->minor = MISC_DYNAMIC_MINOR;
2646 misc->name = DEVICE_NAME;
2647 misc->fops = &sev_fops;
2648
2649 ret = misc_register(misc);
2650 if (ret)
2651 return ret;
2652
2653 kref_init(&misc_dev->refcount);
2654 } else {
2655 kref_get(&misc_dev->refcount);
2656 }
2657
2658 init_waitqueue_head(&sev->int_queue);
2659 sev->misc = misc_dev;
2660 dev_dbg(dev, "registered SEV device\n");
2661
2662 return 0;
2663 }
2664
sev_dev_init(struct psp_device * psp)2665 int sev_dev_init(struct psp_device *psp)
2666 {
2667 struct device *dev = psp->dev;
2668 struct sev_device *sev;
2669 int ret = -ENOMEM;
2670
2671 if (!boot_cpu_has(X86_FEATURE_SEV)) {
2672 dev_info_once(dev, "SEV: memory encryption not enabled by BIOS\n");
2673 return 0;
2674 }
2675
2676 sev = devm_kzalloc(dev, sizeof(*sev), GFP_KERNEL);
2677 if (!sev)
2678 goto e_err;
2679
2680 sev->cmd_buf = (void *)devm_get_free_pages(dev, GFP_KERNEL, 1);
2681 if (!sev->cmd_buf)
2682 goto e_sev;
2683
2684 sev->cmd_buf_backup = (uint8_t *)sev->cmd_buf + PAGE_SIZE;
2685
2686 psp->sev_data = sev;
2687
2688 sev->dev = dev;
2689 sev->psp = psp;
2690
2691 sev->io_regs = psp->io_regs;
2692
2693 sev->vdata = (struct sev_vdata *)psp->vdata->sev;
2694 if (!sev->vdata) {
2695 ret = -ENODEV;
2696 dev_err(dev, "sev: missing driver data\n");
2697 goto e_buf;
2698 }
2699
2700 psp_set_sev_irq_handler(psp, sev_irq_handler, sev);
2701
2702 ret = sev_misc_init(sev);
2703 if (ret)
2704 goto e_irq;
2705
2706 dev_notice(dev, "sev enabled\n");
2707
2708 return 0;
2709
2710 e_irq:
2711 psp_clear_sev_irq_handler(psp);
2712 e_buf:
2713 devm_free_pages(dev, (unsigned long)sev->cmd_buf);
2714 e_sev:
2715 devm_kfree(dev, sev);
2716 e_err:
2717 psp->sev_data = NULL;
2718
2719 dev_notice(dev, "sev initialization failed\n");
2720
2721 return ret;
2722 }
2723
__sev_firmware_shutdown(struct sev_device * sev,bool panic)2724 static void __sev_firmware_shutdown(struct sev_device *sev, bool panic)
2725 {
2726 int error;
2727
2728 __sev_platform_shutdown_locked(&error);
2729
2730 if (sev_es_tmr) {
2731 /*
2732 * The TMR area was encrypted, flush it from the cache.
2733 *
2734 * If invoked during panic handling, local interrupts are
2735 * disabled and all CPUs are stopped, so wbinvd_on_all_cpus()
2736 * can't be used. In that case, wbinvd() is done on remote CPUs
2737 * via the NMI callback, and done for this CPU later during
2738 * SNP shutdown, so wbinvd_on_all_cpus() can be skipped.
2739 */
2740 if (!panic)
2741 wbinvd_on_all_cpus();
2742
2743 __snp_free_firmware_pages(virt_to_page(sev_es_tmr),
2744 get_order(sev_es_tmr_size),
2745 true);
2746 sev_es_tmr = NULL;
2747 }
2748
2749 if (sev_init_ex_buffer) {
2750 __snp_free_firmware_pages(virt_to_page(sev_init_ex_buffer),
2751 get_order(NV_LENGTH),
2752 true);
2753 sev_init_ex_buffer = NULL;
2754 }
2755
2756 if (snp_range_list) {
2757 kfree(snp_range_list);
2758 snp_range_list = NULL;
2759 }
2760
2761 __sev_snp_shutdown_locked(&error, panic);
2762 }
2763
sev_firmware_shutdown(struct sev_device * sev)2764 static void sev_firmware_shutdown(struct sev_device *sev)
2765 {
2766 mutex_lock(&sev_cmd_mutex);
2767 __sev_firmware_shutdown(sev, false);
2768 mutex_unlock(&sev_cmd_mutex);
2769 }
2770
sev_platform_shutdown(void)2771 void sev_platform_shutdown(void)
2772 {
2773 if (!psp_master || !psp_master->sev_data)
2774 return;
2775
2776 sev_firmware_shutdown(psp_master->sev_data);
2777 }
2778 EXPORT_SYMBOL_GPL(sev_platform_shutdown);
2779
sev_dev_destroy(struct psp_device * psp)2780 void sev_dev_destroy(struct psp_device *psp)
2781 {
2782 struct sev_device *sev = psp->sev_data;
2783
2784 if (!sev)
2785 return;
2786
2787 sev_firmware_shutdown(sev);
2788
2789 if (sev->misc)
2790 kref_put(&misc_dev->refcount, sev_exit);
2791
2792 psp_clear_sev_irq_handler(psp);
2793 }
2794
snp_shutdown_on_panic(struct notifier_block * nb,unsigned long reason,void * arg)2795 static int snp_shutdown_on_panic(struct notifier_block *nb,
2796 unsigned long reason, void *arg)
2797 {
2798 struct sev_device *sev = psp_master->sev_data;
2799
2800 /*
2801 * If sev_cmd_mutex is already acquired, then it's likely
2802 * another PSP command is in flight and issuing a shutdown
2803 * would fail in unexpected ways. Rather than create even
2804 * more confusion during a panic, just bail out here.
2805 */
2806 if (mutex_is_locked(&sev_cmd_mutex))
2807 return NOTIFY_DONE;
2808
2809 __sev_firmware_shutdown(sev, true);
2810
2811 return NOTIFY_DONE;
2812 }
2813
sev_issue_cmd_external_user(struct file * filep,unsigned int cmd,void * data,int * error)2814 int sev_issue_cmd_external_user(struct file *filep, unsigned int cmd,
2815 void *data, int *error)
2816 {
2817 if (!filep || filep->f_op != &sev_fops)
2818 return -EBADF;
2819
2820 return sev_do_cmd(cmd, data, error);
2821 }
2822 EXPORT_SYMBOL_GPL(sev_issue_cmd_external_user);
2823
sev_pci_init(void)2824 void sev_pci_init(void)
2825 {
2826 struct sev_device *sev = psp_master->sev_data;
2827 u8 api_major, api_minor, build;
2828
2829 if (!sev)
2830 return;
2831
2832 psp_timeout = psp_probe_timeout;
2833
2834 if (sev_get_api_version())
2835 goto err;
2836
2837 api_major = sev->api_major;
2838 api_minor = sev->api_minor;
2839 build = sev->build;
2840
2841 if (sev_update_firmware(sev->dev) == 0)
2842 sev_get_api_version();
2843
2844 if (api_major != sev->api_major || api_minor != sev->api_minor ||
2845 build != sev->build)
2846 dev_info(sev->dev, "SEV firmware updated from %d.%d.%d to %d.%d.%d\n",
2847 api_major, api_minor, build,
2848 sev->api_major, sev->api_minor, sev->build);
2849
2850 return;
2851
2852 err:
2853 sev_dev_destroy(psp_master);
2854
2855 psp_master->sev_data = NULL;
2856 }
2857
sev_pci_exit(void)2858 void sev_pci_exit(void)
2859 {
2860 struct sev_device *sev = psp_master->sev_data;
2861
2862 if (!sev)
2863 return;
2864
2865 sev_firmware_shutdown(sev);
2866 }
2867