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, ®, 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