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 #if IS_ENABLED(CONFIG_PCI_TSM)
79 static bool sev_tio_enabled = true;
80 module_param_named(tio, sev_tio_enabled, bool, 0444);
81 MODULE_PARM_DESC(tio, "Enables TIO in SNP_INIT_EX");
82 #else
83 static const bool sev_tio_enabled = false;
84 #endif
85
86 MODULE_FIRMWARE("amd/amd_sev_fam17h_model0xh.sbin"); /* 1st gen EPYC */
87 MODULE_FIRMWARE("amd/amd_sev_fam17h_model3xh.sbin"); /* 2nd gen EPYC */
88 MODULE_FIRMWARE("amd/amd_sev_fam19h_model0xh.sbin"); /* 3rd gen EPYC */
89 MODULE_FIRMWARE("amd/amd_sev_fam19h_model1xh.sbin"); /* 4th gen EPYC */
90
91 static bool psp_dead;
92 static int psp_timeout;
93
94 enum snp_hv_fixed_pages_state {
95 ALLOCATED,
96 HV_FIXED,
97 };
98
99 struct snp_hv_fixed_pages_entry {
100 struct list_head list;
101 struct page *page;
102 unsigned int order;
103 bool free;
104 enum snp_hv_fixed_pages_state page_state;
105 };
106
107 static LIST_HEAD(snp_hv_fixed_pages);
108
109 /* Trusted Memory Region (TMR):
110 * The TMR is a 1MB area that must be 1MB aligned. Use the page allocator
111 * to allocate the memory, which will return aligned memory for the specified
112 * allocation order.
113 *
114 * When SEV-SNP is enabled the TMR needs to be 2MB aligned and 2MB sized.
115 */
116 #define SEV_TMR_SIZE (1024 * 1024)
117 #define SNP_TMR_SIZE (2 * 1024 * 1024)
118
119 static void *sev_es_tmr;
120 static size_t sev_es_tmr_size = SEV_TMR_SIZE;
121
122 /* INIT_EX NV Storage:
123 * The NV Storage is a 32Kb area and must be 4Kb page aligned. Use the page
124 * allocator to allocate the memory, which will return aligned memory for the
125 * specified allocation order.
126 */
127 #define NV_LENGTH (32 * 1024)
128 static void *sev_init_ex_buffer;
129
130 /*
131 * SEV_DATA_RANGE_LIST:
132 * Array containing range of pages that firmware transitions to HV-fixed
133 * page state.
134 */
135 static struct sev_data_range_list *snp_range_list;
136
137 static void __sev_firmware_shutdown(struct sev_device *sev, bool panic);
138
139 static int snp_shutdown_on_panic(struct notifier_block *nb,
140 unsigned long reason, void *arg);
141
142 static struct notifier_block snp_panic_notifier = {
143 .notifier_call = snp_shutdown_on_panic,
144 };
145
sev_version_greater_or_equal(u8 maj,u8 min)146 static inline bool sev_version_greater_or_equal(u8 maj, u8 min)
147 {
148 struct sev_device *sev = psp_master->sev_data;
149
150 if (sev->api_major > maj)
151 return true;
152
153 if (sev->api_major == maj && sev->api_minor >= min)
154 return true;
155
156 return false;
157 }
158
sev_irq_handler(int irq,void * data,unsigned int status)159 static void sev_irq_handler(int irq, void *data, unsigned int status)
160 {
161 struct sev_device *sev = data;
162 int reg;
163
164 /* Check if it is command completion: */
165 if (!(status & SEV_CMD_COMPLETE))
166 return;
167
168 /* Check if it is SEV command completion: */
169 reg = ioread32(sev->io_regs + sev->vdata->cmdresp_reg);
170 if (FIELD_GET(PSP_CMDRESP_RESP, reg)) {
171 sev->int_rcvd = 1;
172 wake_up(&sev->int_queue);
173 }
174 }
175
sev_wait_cmd_ioc(struct sev_device * sev,unsigned int * reg,unsigned int timeout)176 static int sev_wait_cmd_ioc(struct sev_device *sev,
177 unsigned int *reg, unsigned int timeout)
178 {
179 int ret;
180
181 /*
182 * If invoked during panic handling, local interrupts are disabled,
183 * so the PSP command completion interrupt can't be used. Poll for
184 * PSP command completion instead.
185 */
186 if (irqs_disabled()) {
187 unsigned long timeout_usecs = (timeout * USEC_PER_SEC) / 10;
188
189 /* Poll for SEV command completion: */
190 while (timeout_usecs--) {
191 *reg = ioread32(sev->io_regs + sev->vdata->cmdresp_reg);
192 if (*reg & PSP_CMDRESP_RESP)
193 return 0;
194
195 udelay(10);
196 }
197 return -ETIMEDOUT;
198 }
199
200 ret = wait_event_timeout(sev->int_queue,
201 sev->int_rcvd, timeout * HZ);
202 if (!ret)
203 return -ETIMEDOUT;
204
205 *reg = ioread32(sev->io_regs + sev->vdata->cmdresp_reg);
206
207 return 0;
208 }
209
sev_cmd_buffer_len(int cmd)210 static int sev_cmd_buffer_len(int cmd)
211 {
212 switch (cmd) {
213 case SEV_CMD_INIT: return sizeof(struct sev_data_init);
214 case SEV_CMD_INIT_EX: return sizeof(struct sev_data_init_ex);
215 case SEV_CMD_SNP_SHUTDOWN_EX: return sizeof(struct sev_data_snp_shutdown_ex);
216 case SEV_CMD_SNP_INIT_EX: return sizeof(struct sev_data_snp_init_ex);
217 case SEV_CMD_PLATFORM_STATUS: return sizeof(struct sev_user_data_status);
218 case SEV_CMD_PEK_CSR: return sizeof(struct sev_data_pek_csr);
219 case SEV_CMD_PEK_CERT_IMPORT: return sizeof(struct sev_data_pek_cert_import);
220 case SEV_CMD_PDH_CERT_EXPORT: return sizeof(struct sev_data_pdh_cert_export);
221 case SEV_CMD_LAUNCH_START: return sizeof(struct sev_data_launch_start);
222 case SEV_CMD_LAUNCH_UPDATE_DATA: return sizeof(struct sev_data_launch_update_data);
223 case SEV_CMD_LAUNCH_UPDATE_VMSA: return sizeof(struct sev_data_launch_update_vmsa);
224 case SEV_CMD_LAUNCH_FINISH: return sizeof(struct sev_data_launch_finish);
225 case SEV_CMD_LAUNCH_MEASURE: return sizeof(struct sev_data_launch_measure);
226 case SEV_CMD_ACTIVATE: return sizeof(struct sev_data_activate);
227 case SEV_CMD_DEACTIVATE: return sizeof(struct sev_data_deactivate);
228 case SEV_CMD_DECOMMISSION: return sizeof(struct sev_data_decommission);
229 case SEV_CMD_GUEST_STATUS: return sizeof(struct sev_data_guest_status);
230 case SEV_CMD_DBG_DECRYPT: return sizeof(struct sev_data_dbg);
231 case SEV_CMD_DBG_ENCRYPT: return sizeof(struct sev_data_dbg);
232 case SEV_CMD_SEND_START: return sizeof(struct sev_data_send_start);
233 case SEV_CMD_SEND_UPDATE_DATA: return sizeof(struct sev_data_send_update_data);
234 case SEV_CMD_SEND_UPDATE_VMSA: return sizeof(struct sev_data_send_update_vmsa);
235 case SEV_CMD_SEND_FINISH: return sizeof(struct sev_data_send_finish);
236 case SEV_CMD_RECEIVE_START: return sizeof(struct sev_data_receive_start);
237 case SEV_CMD_RECEIVE_FINISH: return sizeof(struct sev_data_receive_finish);
238 case SEV_CMD_RECEIVE_UPDATE_DATA: return sizeof(struct sev_data_receive_update_data);
239 case SEV_CMD_RECEIVE_UPDATE_VMSA: return sizeof(struct sev_data_receive_update_vmsa);
240 case SEV_CMD_LAUNCH_UPDATE_SECRET: return sizeof(struct sev_data_launch_secret);
241 case SEV_CMD_DOWNLOAD_FIRMWARE: return sizeof(struct sev_data_download_firmware);
242 case SEV_CMD_GET_ID: return sizeof(struct sev_data_get_id);
243 case SEV_CMD_ATTESTATION_REPORT: return sizeof(struct sev_data_attestation_report);
244 case SEV_CMD_SEND_CANCEL: return sizeof(struct sev_data_send_cancel);
245 case SEV_CMD_SNP_GCTX_CREATE: return sizeof(struct sev_data_snp_addr);
246 case SEV_CMD_SNP_LAUNCH_START: return sizeof(struct sev_data_snp_launch_start);
247 case SEV_CMD_SNP_LAUNCH_UPDATE: return sizeof(struct sev_data_snp_launch_update);
248 case SEV_CMD_SNP_ACTIVATE: return sizeof(struct sev_data_snp_activate);
249 case SEV_CMD_SNP_DECOMMISSION: return sizeof(struct sev_data_snp_addr);
250 case SEV_CMD_SNP_PAGE_RECLAIM: return sizeof(struct sev_data_snp_page_reclaim);
251 case SEV_CMD_SNP_GUEST_STATUS: return sizeof(struct sev_data_snp_guest_status);
252 case SEV_CMD_SNP_LAUNCH_FINISH: return sizeof(struct sev_data_snp_launch_finish);
253 case SEV_CMD_SNP_DBG_DECRYPT: return sizeof(struct sev_data_snp_dbg);
254 case SEV_CMD_SNP_DBG_ENCRYPT: return sizeof(struct sev_data_snp_dbg);
255 case SEV_CMD_SNP_PAGE_UNSMASH: return sizeof(struct sev_data_snp_page_unsmash);
256 case SEV_CMD_SNP_PLATFORM_STATUS: return sizeof(struct sev_data_snp_addr);
257 case SEV_CMD_SNP_GUEST_REQUEST: return sizeof(struct sev_data_snp_guest_request);
258 case SEV_CMD_SNP_CONFIG: return sizeof(struct sev_user_data_snp_config);
259 case SEV_CMD_SNP_COMMIT: return sizeof(struct sev_data_snp_commit);
260 case SEV_CMD_SNP_FEATURE_INFO: return sizeof(struct sev_data_snp_feature_info);
261 case SEV_CMD_SNP_VLEK_LOAD: return sizeof(struct sev_user_data_snp_vlek_load);
262 default: return sev_tio_cmd_buffer_len(cmd);
263 }
264
265 return 0;
266 }
267
open_file_as_root(const char * filename,int flags,umode_t mode)268 static struct file *open_file_as_root(const char *filename, int flags, umode_t mode)
269 {
270 struct path root __free(path_put) = {};
271
272 task_lock(&init_task);
273 get_fs_root(init_task.fs, &root);
274 task_unlock(&init_task);
275
276 CLASS(prepare_creds, cred)();
277 if (!cred)
278 return ERR_PTR(-ENOMEM);
279
280 cred->fsuid = GLOBAL_ROOT_UID;
281
282 scoped_with_creds(cred)
283 return file_open_root(&root, filename, flags, mode);
284 }
285
sev_read_init_ex_file(void)286 static int sev_read_init_ex_file(void)
287 {
288 struct sev_device *sev = psp_master->sev_data;
289 struct file *fp;
290 ssize_t nread;
291
292 lockdep_assert_held(&sev_cmd_mutex);
293
294 if (!sev_init_ex_buffer)
295 return -EOPNOTSUPP;
296
297 fp = open_file_as_root(init_ex_path, O_RDONLY, 0);
298 if (IS_ERR(fp)) {
299 int ret = PTR_ERR(fp);
300
301 if (ret == -ENOENT) {
302 dev_info(sev->dev,
303 "SEV: %s does not exist and will be created later.\n",
304 init_ex_path);
305 ret = 0;
306 } else {
307 dev_err(sev->dev,
308 "SEV: could not open %s for read, error %d\n",
309 init_ex_path, ret);
310 }
311 return ret;
312 }
313
314 nread = kernel_read(fp, sev_init_ex_buffer, NV_LENGTH, NULL);
315 if (nread != NV_LENGTH) {
316 dev_info(sev->dev,
317 "SEV: could not read %u bytes to non volatile memory area, ret %ld\n",
318 NV_LENGTH, nread);
319 }
320
321 dev_dbg(sev->dev, "SEV: read %ld bytes from NV file\n", nread);
322 filp_close(fp, NULL);
323
324 return 0;
325 }
326
sev_write_init_ex_file(void)327 static int sev_write_init_ex_file(void)
328 {
329 struct sev_device *sev = psp_master->sev_data;
330 struct file *fp;
331 loff_t offset = 0;
332 ssize_t nwrite;
333
334 lockdep_assert_held(&sev_cmd_mutex);
335
336 if (!sev_init_ex_buffer)
337 return 0;
338
339 fp = open_file_as_root(init_ex_path, O_CREAT | O_WRONLY, 0600);
340 if (IS_ERR(fp)) {
341 int ret = PTR_ERR(fp);
342
343 dev_err(sev->dev,
344 "SEV: could not open file for write, error %d\n",
345 ret);
346 return ret;
347 }
348
349 nwrite = kernel_write(fp, sev_init_ex_buffer, NV_LENGTH, &offset);
350 vfs_fsync(fp, 0);
351 filp_close(fp, NULL);
352
353 if (nwrite != NV_LENGTH) {
354 dev_err(sev->dev,
355 "SEV: failed to write %u bytes to non volatile memory area, ret %ld\n",
356 NV_LENGTH, nwrite);
357 return -EIO;
358 }
359
360 dev_dbg(sev->dev, "SEV: write successful to NV file\n");
361
362 return 0;
363 }
364
sev_write_init_ex_file_if_required(int cmd_id)365 static int sev_write_init_ex_file_if_required(int cmd_id)
366 {
367 lockdep_assert_held(&sev_cmd_mutex);
368
369 if (!sev_init_ex_buffer)
370 return 0;
371
372 /*
373 * Only a few platform commands modify the SPI/NV area, but none of the
374 * non-platform commands do. Only INIT(_EX), PLATFORM_RESET, PEK_GEN,
375 * PEK_CERT_IMPORT, and PDH_GEN do.
376 */
377 switch (cmd_id) {
378 case SEV_CMD_FACTORY_RESET:
379 case SEV_CMD_INIT_EX:
380 case SEV_CMD_PDH_GEN:
381 case SEV_CMD_PEK_CERT_IMPORT:
382 case SEV_CMD_PEK_GEN:
383 break;
384 default:
385 return 0;
386 }
387
388 return sev_write_init_ex_file();
389 }
390
snp_reclaim_pages(unsigned long paddr,unsigned int npages,bool locked)391 int snp_reclaim_pages(unsigned long paddr, unsigned int npages, bool locked)
392 {
393 int ret, err, i;
394
395 paddr = __sme_clr(ALIGN_DOWN(paddr, PAGE_SIZE));
396
397 for (i = 0; i < npages; i++, paddr += PAGE_SIZE) {
398 struct sev_data_snp_page_reclaim data = {0};
399
400 data.paddr = paddr;
401
402 if (locked)
403 ret = __sev_do_cmd_locked(SEV_CMD_SNP_PAGE_RECLAIM, &data, &err);
404 else
405 ret = sev_do_cmd(SEV_CMD_SNP_PAGE_RECLAIM, &data, &err);
406
407 if (ret)
408 goto cleanup;
409
410 ret = rmp_make_shared(__phys_to_pfn(paddr), PG_LEVEL_4K);
411 if (ret)
412 goto cleanup;
413 }
414
415 return 0;
416
417 cleanup:
418 /*
419 * If there was a failure reclaiming the page then it is no longer safe
420 * to release it back to the system; leak it instead.
421 */
422 snp_leak_pages(__phys_to_pfn(paddr), npages - i);
423 return ret;
424 }
425 EXPORT_SYMBOL_GPL(snp_reclaim_pages);
426
rmp_mark_pages_firmware(unsigned long paddr,unsigned int npages,bool locked)427 static int rmp_mark_pages_firmware(unsigned long paddr, unsigned int npages, bool locked)
428 {
429 unsigned long pfn = __sme_clr(paddr) >> PAGE_SHIFT;
430 int rc, i;
431
432 for (i = 0; i < npages; i++, pfn++) {
433 rc = rmp_make_private(pfn, 0, PG_LEVEL_4K, 0, true);
434 if (rc)
435 goto cleanup;
436 }
437
438 return 0;
439
440 cleanup:
441 /*
442 * Try unrolling the firmware state changes by
443 * reclaiming the pages which were already changed to the
444 * firmware state.
445 */
446 snp_reclaim_pages(paddr, i, locked);
447
448 return rc;
449 }
450
__snp_alloc_firmware_pages(gfp_t gfp_mask,int order,bool locked)451 static struct page *__snp_alloc_firmware_pages(gfp_t gfp_mask, int order, bool locked)
452 {
453 unsigned long npages = 1ul << order, paddr;
454 struct sev_device *sev;
455 struct page *page;
456
457 if (!psp_master || !psp_master->sev_data)
458 return NULL;
459
460 page = alloc_pages(gfp_mask, order);
461 if (!page)
462 return NULL;
463
464 /* If SEV-SNP is initialized then add the page in RMP table. */
465 sev = psp_master->sev_data;
466 if (!sev->snp_initialized)
467 return page;
468
469 paddr = __pa((unsigned long)page_address(page));
470 if (rmp_mark_pages_firmware(paddr, npages, locked))
471 return NULL;
472
473 return page;
474 }
475
snp_alloc_firmware_page(gfp_t gfp_mask)476 void *snp_alloc_firmware_page(gfp_t gfp_mask)
477 {
478 struct page *page;
479
480 page = __snp_alloc_firmware_pages(gfp_mask, 0, false);
481
482 return page ? page_address(page) : NULL;
483 }
484 EXPORT_SYMBOL_GPL(snp_alloc_firmware_page);
485
__snp_free_firmware_pages(struct page * page,int order,bool locked)486 static void __snp_free_firmware_pages(struct page *page, int order, bool locked)
487 {
488 struct sev_device *sev = psp_master->sev_data;
489 unsigned long paddr, npages = 1ul << order;
490
491 if (!page)
492 return;
493
494 paddr = __pa((unsigned long)page_address(page));
495 if (sev->snp_initialized &&
496 snp_reclaim_pages(paddr, npages, locked))
497 return;
498
499 __free_pages(page, order);
500 }
501
snp_free_firmware_page(void * addr)502 void snp_free_firmware_page(void *addr)
503 {
504 if (!addr)
505 return;
506
507 __snp_free_firmware_pages(virt_to_page(addr), 0, false);
508 }
509 EXPORT_SYMBOL_GPL(snp_free_firmware_page);
510
sev_fw_alloc(unsigned long len)511 static void *sev_fw_alloc(unsigned long len)
512 {
513 struct page *page;
514
515 page = __snp_alloc_firmware_pages(GFP_KERNEL, get_order(len), true);
516 if (!page)
517 return NULL;
518
519 return page_address(page);
520 }
521
522 /**
523 * struct cmd_buf_desc - descriptors for managing legacy SEV command address
524 * parameters corresponding to buffers that may be written to by firmware.
525 *
526 * @paddr_ptr: pointer to the address parameter in the command buffer which may
527 * need to be saved/restored depending on whether a bounce buffer
528 * is used. In the case of a bounce buffer, the command buffer
529 * needs to be updated with the address of the new bounce buffer
530 * snp_map_cmd_buf_desc() has allocated specifically for it. Must
531 * be NULL if this descriptor is only an end-of-list indicator.
532 *
533 * @paddr_orig: storage for the original address parameter, which can be used to
534 * restore the original value in @paddr_ptr in cases where it is
535 * replaced with the address of a bounce buffer.
536 *
537 * @len: length of buffer located at the address originally stored at @paddr_ptr
538 *
539 * @guest_owned: true if the address corresponds to guest-owned pages, in which
540 * case bounce buffers are not needed.
541 */
542 struct cmd_buf_desc {
543 u64 *paddr_ptr;
544 u64 paddr_orig;
545 u32 len;
546 bool guest_owned;
547 };
548
549 /*
550 * If a legacy SEV command parameter is a memory address, those pages in
551 * turn need to be transitioned to/from firmware-owned before/after
552 * executing the firmware command.
553 *
554 * Additionally, in cases where those pages are not guest-owned, a bounce
555 * buffer is needed in place of the original memory address parameter.
556 *
557 * A set of descriptors are used to keep track of this handling, and
558 * initialized here based on the specific commands being executed.
559 */
snp_populate_cmd_buf_desc_list(int cmd,void * cmd_buf,struct cmd_buf_desc * desc_list)560 static void snp_populate_cmd_buf_desc_list(int cmd, void *cmd_buf,
561 struct cmd_buf_desc *desc_list)
562 {
563 switch (cmd) {
564 case SEV_CMD_PDH_CERT_EXPORT: {
565 struct sev_data_pdh_cert_export *data = cmd_buf;
566
567 desc_list[0].paddr_ptr = &data->pdh_cert_address;
568 desc_list[0].len = data->pdh_cert_len;
569 desc_list[1].paddr_ptr = &data->cert_chain_address;
570 desc_list[1].len = data->cert_chain_len;
571 break;
572 }
573 case SEV_CMD_GET_ID: {
574 struct sev_data_get_id *data = cmd_buf;
575
576 desc_list[0].paddr_ptr = &data->address;
577 desc_list[0].len = data->len;
578 break;
579 }
580 case SEV_CMD_PEK_CSR: {
581 struct sev_data_pek_csr *data = cmd_buf;
582
583 desc_list[0].paddr_ptr = &data->address;
584 desc_list[0].len = data->len;
585 break;
586 }
587 case SEV_CMD_LAUNCH_UPDATE_DATA: {
588 struct sev_data_launch_update_data *data = cmd_buf;
589
590 desc_list[0].paddr_ptr = &data->address;
591 desc_list[0].len = data->len;
592 desc_list[0].guest_owned = true;
593 break;
594 }
595 case SEV_CMD_LAUNCH_UPDATE_VMSA: {
596 struct sev_data_launch_update_vmsa *data = cmd_buf;
597
598 desc_list[0].paddr_ptr = &data->address;
599 desc_list[0].len = data->len;
600 desc_list[0].guest_owned = true;
601 break;
602 }
603 case SEV_CMD_LAUNCH_MEASURE: {
604 struct sev_data_launch_measure *data = cmd_buf;
605
606 desc_list[0].paddr_ptr = &data->address;
607 desc_list[0].len = data->len;
608 break;
609 }
610 case SEV_CMD_LAUNCH_UPDATE_SECRET: {
611 struct sev_data_launch_secret *data = cmd_buf;
612
613 desc_list[0].paddr_ptr = &data->guest_address;
614 desc_list[0].len = data->guest_len;
615 desc_list[0].guest_owned = true;
616 break;
617 }
618 case SEV_CMD_DBG_DECRYPT: {
619 struct sev_data_dbg *data = cmd_buf;
620
621 desc_list[0].paddr_ptr = &data->dst_addr;
622 desc_list[0].len = data->len;
623 desc_list[0].guest_owned = true;
624 break;
625 }
626 case SEV_CMD_DBG_ENCRYPT: {
627 struct sev_data_dbg *data = cmd_buf;
628
629 desc_list[0].paddr_ptr = &data->dst_addr;
630 desc_list[0].len = data->len;
631 desc_list[0].guest_owned = true;
632 break;
633 }
634 case SEV_CMD_ATTESTATION_REPORT: {
635 struct sev_data_attestation_report *data = cmd_buf;
636
637 desc_list[0].paddr_ptr = &data->address;
638 desc_list[0].len = data->len;
639 break;
640 }
641 case SEV_CMD_SEND_START: {
642 struct sev_data_send_start *data = cmd_buf;
643
644 desc_list[0].paddr_ptr = &data->session_address;
645 desc_list[0].len = data->session_len;
646 break;
647 }
648 case SEV_CMD_SEND_UPDATE_DATA: {
649 struct sev_data_send_update_data *data = cmd_buf;
650
651 desc_list[0].paddr_ptr = &data->hdr_address;
652 desc_list[0].len = data->hdr_len;
653 desc_list[1].paddr_ptr = &data->trans_address;
654 desc_list[1].len = data->trans_len;
655 break;
656 }
657 case SEV_CMD_SEND_UPDATE_VMSA: {
658 struct sev_data_send_update_vmsa *data = cmd_buf;
659
660 desc_list[0].paddr_ptr = &data->hdr_address;
661 desc_list[0].len = data->hdr_len;
662 desc_list[1].paddr_ptr = &data->trans_address;
663 desc_list[1].len = data->trans_len;
664 break;
665 }
666 case SEV_CMD_RECEIVE_UPDATE_DATA: {
667 struct sev_data_receive_update_data *data = cmd_buf;
668
669 desc_list[0].paddr_ptr = &data->guest_address;
670 desc_list[0].len = data->guest_len;
671 desc_list[0].guest_owned = true;
672 break;
673 }
674 case SEV_CMD_RECEIVE_UPDATE_VMSA: {
675 struct sev_data_receive_update_vmsa *data = cmd_buf;
676
677 desc_list[0].paddr_ptr = &data->guest_address;
678 desc_list[0].len = data->guest_len;
679 desc_list[0].guest_owned = true;
680 break;
681 }
682 default:
683 break;
684 }
685 }
686
snp_map_cmd_buf_desc(struct cmd_buf_desc * desc)687 static int snp_map_cmd_buf_desc(struct cmd_buf_desc *desc)
688 {
689 unsigned int npages;
690
691 if (!desc->len)
692 return 0;
693
694 /* Allocate a bounce buffer if this isn't a guest owned page. */
695 if (!desc->guest_owned) {
696 struct page *page;
697
698 page = alloc_pages(GFP_KERNEL_ACCOUNT, get_order(desc->len));
699 if (!page) {
700 pr_warn("Failed to allocate bounce buffer for SEV legacy command.\n");
701 return -ENOMEM;
702 }
703
704 desc->paddr_orig = *desc->paddr_ptr;
705 *desc->paddr_ptr = __psp_pa(page_to_virt(page));
706 }
707
708 npages = PAGE_ALIGN(desc->len) >> PAGE_SHIFT;
709
710 /* Transition the buffer to firmware-owned. */
711 if (rmp_mark_pages_firmware(*desc->paddr_ptr, npages, true)) {
712 pr_warn("Error moving pages to firmware-owned state for SEV legacy command.\n");
713 return -EFAULT;
714 }
715
716 return 0;
717 }
718
snp_unmap_cmd_buf_desc(struct cmd_buf_desc * desc)719 static int snp_unmap_cmd_buf_desc(struct cmd_buf_desc *desc)
720 {
721 unsigned int npages;
722
723 if (!desc->len)
724 return 0;
725
726 npages = PAGE_ALIGN(desc->len) >> PAGE_SHIFT;
727
728 /* Transition the buffers back to hypervisor-owned. */
729 if (snp_reclaim_pages(*desc->paddr_ptr, npages, true)) {
730 pr_warn("Failed to reclaim firmware-owned pages while issuing SEV legacy command.\n");
731 return -EFAULT;
732 }
733
734 /* Copy data from bounce buffer and then free it. */
735 if (!desc->guest_owned) {
736 void *bounce_buf = __va(__sme_clr(*desc->paddr_ptr));
737 void *dst_buf = __va(__sme_clr(desc->paddr_orig));
738
739 memcpy(dst_buf, bounce_buf, desc->len);
740 __free_pages(virt_to_page(bounce_buf), get_order(desc->len));
741
742 /* Restore the original address in the command buffer. */
743 *desc->paddr_ptr = desc->paddr_orig;
744 }
745
746 return 0;
747 }
748
snp_map_cmd_buf_desc_list(int cmd,void * cmd_buf,struct cmd_buf_desc * desc_list)749 static int snp_map_cmd_buf_desc_list(int cmd, void *cmd_buf, struct cmd_buf_desc *desc_list)
750 {
751 int i;
752
753 snp_populate_cmd_buf_desc_list(cmd, cmd_buf, desc_list);
754
755 for (i = 0; i < CMD_BUF_DESC_MAX; i++) {
756 struct cmd_buf_desc *desc = &desc_list[i];
757
758 if (!desc->paddr_ptr)
759 break;
760
761 if (snp_map_cmd_buf_desc(desc))
762 goto err_unmap;
763 }
764
765 return 0;
766
767 err_unmap:
768 for (i--; i >= 0; i--)
769 snp_unmap_cmd_buf_desc(&desc_list[i]);
770
771 return -EFAULT;
772 }
773
snp_unmap_cmd_buf_desc_list(struct cmd_buf_desc * desc_list)774 static int snp_unmap_cmd_buf_desc_list(struct cmd_buf_desc *desc_list)
775 {
776 int i, ret = 0;
777
778 for (i = 0; i < CMD_BUF_DESC_MAX; i++) {
779 struct cmd_buf_desc *desc = &desc_list[i];
780
781 if (!desc->paddr_ptr)
782 break;
783
784 if (snp_unmap_cmd_buf_desc(&desc_list[i]))
785 ret = -EFAULT;
786 }
787
788 return ret;
789 }
790
sev_cmd_buf_writable(int cmd)791 static bool sev_cmd_buf_writable(int cmd)
792 {
793 switch (cmd) {
794 case SEV_CMD_PLATFORM_STATUS:
795 case SEV_CMD_GUEST_STATUS:
796 case SEV_CMD_LAUNCH_START:
797 case SEV_CMD_RECEIVE_START:
798 case SEV_CMD_LAUNCH_MEASURE:
799 case SEV_CMD_SEND_START:
800 case SEV_CMD_SEND_UPDATE_DATA:
801 case SEV_CMD_SEND_UPDATE_VMSA:
802 case SEV_CMD_PEK_CSR:
803 case SEV_CMD_PDH_CERT_EXPORT:
804 case SEV_CMD_GET_ID:
805 case SEV_CMD_ATTESTATION_REPORT:
806 return true;
807 default:
808 return false;
809 }
810 }
811
812 /* After SNP is INIT'ed, the behavior of legacy SEV commands is changed. */
snp_legacy_handling_needed(int cmd)813 static bool snp_legacy_handling_needed(int cmd)
814 {
815 struct sev_device *sev = psp_master->sev_data;
816
817 return cmd < SEV_CMD_SNP_INIT && sev->snp_initialized;
818 }
819
snp_prep_cmd_buf(int cmd,void * cmd_buf,struct cmd_buf_desc * desc_list)820 static int snp_prep_cmd_buf(int cmd, void *cmd_buf, struct cmd_buf_desc *desc_list)
821 {
822 if (!snp_legacy_handling_needed(cmd))
823 return 0;
824
825 if (snp_map_cmd_buf_desc_list(cmd, cmd_buf, desc_list))
826 return -EFAULT;
827
828 /*
829 * Before command execution, the command buffer needs to be put into
830 * the firmware-owned state.
831 */
832 if (sev_cmd_buf_writable(cmd)) {
833 if (rmp_mark_pages_firmware(__pa(cmd_buf), 1, true))
834 return -EFAULT;
835 }
836
837 return 0;
838 }
839
snp_reclaim_cmd_buf(int cmd,void * cmd_buf)840 static int snp_reclaim_cmd_buf(int cmd, void *cmd_buf)
841 {
842 if (!snp_legacy_handling_needed(cmd))
843 return 0;
844
845 /*
846 * After command completion, the command buffer needs to be put back
847 * into the hypervisor-owned state.
848 */
849 if (sev_cmd_buf_writable(cmd))
850 if (snp_reclaim_pages(__pa(cmd_buf), 1, true))
851 return -EFAULT;
852
853 return 0;
854 }
855
__sev_do_cmd_locked(int cmd,void * data,int * psp_ret)856 int __sev_do_cmd_locked(int cmd, void *data, int *psp_ret)
857 {
858 struct cmd_buf_desc desc_list[CMD_BUF_DESC_MAX] = {0};
859 struct psp_device *psp = psp_master;
860 struct sev_device *sev;
861 unsigned int cmdbuff_hi, cmdbuff_lo;
862 unsigned int phys_lsb, phys_msb;
863 unsigned int reg;
864 void *cmd_buf;
865 int buf_len;
866 int ret = 0;
867
868 if (!psp || !psp->sev_data)
869 return -ENODEV;
870
871 if (psp_dead)
872 return -EBUSY;
873
874 sev = psp->sev_data;
875
876 buf_len = sev_cmd_buffer_len(cmd);
877 if (WARN_ON_ONCE(!data != !buf_len))
878 return -EINVAL;
879
880 /*
881 * Copy the incoming data to driver's scratch buffer as __pa() will not
882 * work for some memory, e.g. vmalloc'd addresses, and @data may not be
883 * physically contiguous.
884 */
885 if (data) {
886 /*
887 * Commands are generally issued one at a time and require the
888 * sev_cmd_mutex, but there could be recursive firmware requests
889 * due to SEV_CMD_SNP_PAGE_RECLAIM needing to be issued while
890 * preparing buffers for another command. This is the only known
891 * case of nesting in the current code, so exactly one
892 * additional command buffer is available for that purpose.
893 */
894 if (!sev->cmd_buf_active) {
895 cmd_buf = sev->cmd_buf;
896 sev->cmd_buf_active = true;
897 } else if (!sev->cmd_buf_backup_active) {
898 cmd_buf = sev->cmd_buf_backup;
899 sev->cmd_buf_backup_active = true;
900 } else {
901 dev_err(sev->dev,
902 "SEV: too many firmware commands in progress, no command buffers available.\n");
903 return -EBUSY;
904 }
905
906 memcpy(cmd_buf, data, buf_len);
907
908 /*
909 * The behavior of the SEV-legacy commands is altered when the
910 * SNP firmware is in the INIT state.
911 */
912 ret = snp_prep_cmd_buf(cmd, cmd_buf, desc_list);
913 if (ret) {
914 dev_err(sev->dev,
915 "SEV: failed to prepare buffer for legacy command 0x%x. Error: %d\n",
916 cmd, ret);
917 return ret;
918 }
919 } else {
920 cmd_buf = sev->cmd_buf;
921 }
922
923 /* Get the physical address of the command buffer */
924 phys_lsb = data ? lower_32_bits(__psp_pa(cmd_buf)) : 0;
925 phys_msb = data ? upper_32_bits(__psp_pa(cmd_buf)) : 0;
926
927 dev_dbg(sev->dev, "sev command id %#x buffer 0x%08x%08x timeout %us\n",
928 cmd, phys_msb, phys_lsb, psp_timeout);
929
930 print_hex_dump_debug("(in): ", DUMP_PREFIX_OFFSET, 16, 2, data,
931 buf_len, false);
932
933 iowrite32(phys_lsb, sev->io_regs + sev->vdata->cmdbuff_addr_lo_reg);
934 iowrite32(phys_msb, sev->io_regs + sev->vdata->cmdbuff_addr_hi_reg);
935
936 sev->int_rcvd = 0;
937
938 reg = FIELD_PREP(SEV_CMDRESP_CMD, cmd);
939
940 /*
941 * If invoked during panic handling, local interrupts are disabled so
942 * the PSP command completion interrupt can't be used.
943 * sev_wait_cmd_ioc() already checks for interrupts disabled and
944 * polls for PSP command completion. Ensure we do not request an
945 * interrupt from the PSP if irqs disabled.
946 */
947 if (!irqs_disabled())
948 reg |= SEV_CMDRESP_IOC;
949
950 iowrite32(reg, sev->io_regs + sev->vdata->cmdresp_reg);
951
952 /* wait for command completion */
953 ret = sev_wait_cmd_ioc(sev, ®, psp_timeout);
954 if (ret) {
955 if (psp_ret)
956 *psp_ret = 0;
957
958 dev_err(sev->dev, "sev command %#x timed out, disabling PSP\n", cmd);
959 psp_dead = true;
960
961 return ret;
962 }
963
964 psp_timeout = psp_cmd_timeout;
965
966 if (psp_ret)
967 *psp_ret = FIELD_GET(PSP_CMDRESP_STS, reg);
968
969 if (FIELD_GET(PSP_CMDRESP_STS, reg)) {
970 dev_dbg(sev->dev, "sev command %#x failed (%#010lx)\n",
971 cmd, FIELD_GET(PSP_CMDRESP_STS, reg));
972
973 /*
974 * PSP firmware may report additional error information in the
975 * command buffer registers on error. Print contents of command
976 * buffer registers if they changed.
977 */
978 cmdbuff_hi = ioread32(sev->io_regs + sev->vdata->cmdbuff_addr_hi_reg);
979 cmdbuff_lo = ioread32(sev->io_regs + sev->vdata->cmdbuff_addr_lo_reg);
980 if (cmdbuff_hi != phys_msb || cmdbuff_lo != phys_lsb) {
981 dev_dbg(sev->dev, "Additional error information reported in cmdbuff:");
982 dev_dbg(sev->dev, " cmdbuff hi: %#010x\n", cmdbuff_hi);
983 dev_dbg(sev->dev, " cmdbuff lo: %#010x\n", cmdbuff_lo);
984 }
985 ret = -EIO;
986 } else {
987 ret = sev_write_init_ex_file_if_required(cmd);
988 }
989
990 /*
991 * Copy potential output from the PSP back to data. Do this even on
992 * failure in case the caller wants to glean something from the error.
993 */
994 if (data) {
995 int ret_reclaim;
996 /*
997 * Restore the page state after the command completes.
998 */
999 ret_reclaim = snp_reclaim_cmd_buf(cmd, cmd_buf);
1000 if (ret_reclaim) {
1001 dev_err(sev->dev,
1002 "SEV: failed to reclaim buffer for legacy command %#x. Error: %d\n",
1003 cmd, ret_reclaim);
1004 return ret_reclaim;
1005 }
1006
1007 memcpy(data, cmd_buf, buf_len);
1008
1009 if (sev->cmd_buf_backup_active)
1010 sev->cmd_buf_backup_active = false;
1011 else
1012 sev->cmd_buf_active = false;
1013
1014 if (snp_unmap_cmd_buf_desc_list(desc_list))
1015 return -EFAULT;
1016 }
1017
1018 print_hex_dump_debug("(out): ", DUMP_PREFIX_OFFSET, 16, 2, data,
1019 buf_len, false);
1020
1021 return ret;
1022 }
1023
sev_do_cmd(int cmd,void * data,int * psp_ret)1024 int sev_do_cmd(int cmd, void *data, int *psp_ret)
1025 {
1026 int rc;
1027
1028 mutex_lock(&sev_cmd_mutex);
1029 rc = __sev_do_cmd_locked(cmd, data, psp_ret);
1030 mutex_unlock(&sev_cmd_mutex);
1031
1032 return rc;
1033 }
1034 EXPORT_SYMBOL_GPL(sev_do_cmd);
1035
__sev_init_locked(int * error)1036 static int __sev_init_locked(int *error)
1037 {
1038 struct sev_data_init data;
1039
1040 memset(&data, 0, sizeof(data));
1041 if (sev_es_tmr) {
1042 /*
1043 * Do not include the encryption mask on the physical
1044 * address of the TMR (firmware should clear it anyway).
1045 */
1046 data.tmr_address = __pa(sev_es_tmr);
1047
1048 data.flags |= SEV_INIT_FLAGS_SEV_ES;
1049 data.tmr_len = sev_es_tmr_size;
1050 }
1051
1052 return __sev_do_cmd_locked(SEV_CMD_INIT, &data, error);
1053 }
1054
__sev_init_ex_locked(int * error)1055 static int __sev_init_ex_locked(int *error)
1056 {
1057 struct sev_data_init_ex data;
1058
1059 memset(&data, 0, sizeof(data));
1060 data.length = sizeof(data);
1061 data.nv_address = __psp_pa(sev_init_ex_buffer);
1062 data.nv_len = NV_LENGTH;
1063
1064 if (sev_es_tmr) {
1065 /*
1066 * Do not include the encryption mask on the physical
1067 * address of the TMR (firmware should clear it anyway).
1068 */
1069 data.tmr_address = __pa(sev_es_tmr);
1070
1071 data.flags |= SEV_INIT_FLAGS_SEV_ES;
1072 data.tmr_len = sev_es_tmr_size;
1073 }
1074
1075 return __sev_do_cmd_locked(SEV_CMD_INIT_EX, &data, error);
1076 }
1077
__sev_do_init_locked(int * psp_ret)1078 static inline int __sev_do_init_locked(int *psp_ret)
1079 {
1080 if (sev_init_ex_buffer)
1081 return __sev_init_ex_locked(psp_ret);
1082 else
1083 return __sev_init_locked(psp_ret);
1084 }
1085
snp_set_hsave_pa(void * arg)1086 static void snp_set_hsave_pa(void *arg)
1087 {
1088 wrmsrq(MSR_VM_HSAVE_PA, 0);
1089 }
1090
1091 /* Hypervisor Fixed pages API interface */
snp_hv_fixed_pages_state_update(struct sev_device * sev,enum snp_hv_fixed_pages_state page_state)1092 static void snp_hv_fixed_pages_state_update(struct sev_device *sev,
1093 enum snp_hv_fixed_pages_state page_state)
1094 {
1095 struct snp_hv_fixed_pages_entry *entry;
1096
1097 /* List is protected by sev_cmd_mutex */
1098 lockdep_assert_held(&sev_cmd_mutex);
1099
1100 if (list_empty(&snp_hv_fixed_pages))
1101 return;
1102
1103 list_for_each_entry(entry, &snp_hv_fixed_pages, list)
1104 entry->page_state = page_state;
1105 }
1106
1107 /*
1108 * Allocate HV_FIXED pages in 2MB aligned sizes to ensure the whole
1109 * 2MB pages are marked as HV_FIXED.
1110 */
snp_alloc_hv_fixed_pages(unsigned int num_2mb_pages)1111 struct page *snp_alloc_hv_fixed_pages(unsigned int num_2mb_pages)
1112 {
1113 struct psp_device *psp_master = psp_get_master_device();
1114 struct snp_hv_fixed_pages_entry *entry;
1115 struct sev_device *sev;
1116 unsigned int order;
1117 struct page *page;
1118
1119 if (!psp_master || !psp_master->sev_data)
1120 return NULL;
1121
1122 sev = psp_master->sev_data;
1123
1124 order = get_order(PMD_SIZE * num_2mb_pages);
1125
1126 /*
1127 * SNP_INIT_EX is protected by sev_cmd_mutex, therefore this list
1128 * also needs to be protected using the same mutex.
1129 */
1130 guard(mutex)(&sev_cmd_mutex);
1131
1132 /*
1133 * This API uses SNP_INIT_EX to transition allocated pages to HV_Fixed
1134 * page state, fail if SNP is already initialized.
1135 */
1136 if (sev->snp_initialized)
1137 return NULL;
1138
1139 /* Re-use freed pages that match the request */
1140 list_for_each_entry(entry, &snp_hv_fixed_pages, list) {
1141 /* Hypervisor fixed page allocator implements exact fit policy */
1142 if (entry->order == order && entry->free) {
1143 entry->free = false;
1144 memset(page_address(entry->page), 0,
1145 (1 << entry->order) * PAGE_SIZE);
1146 return entry->page;
1147 }
1148 }
1149
1150 page = alloc_pages(GFP_KERNEL | __GFP_ZERO, order);
1151 if (!page)
1152 return NULL;
1153
1154 entry = kzalloc(sizeof(*entry), GFP_KERNEL);
1155 if (!entry) {
1156 __free_pages(page, order);
1157 return NULL;
1158 }
1159
1160 entry->page = page;
1161 entry->order = order;
1162 list_add_tail(&entry->list, &snp_hv_fixed_pages);
1163
1164 return page;
1165 }
1166
snp_free_hv_fixed_pages(struct page * page)1167 void snp_free_hv_fixed_pages(struct page *page)
1168 {
1169 struct psp_device *psp_master = psp_get_master_device();
1170 struct snp_hv_fixed_pages_entry *entry, *nentry;
1171
1172 if (!psp_master || !psp_master->sev_data)
1173 return;
1174
1175 /*
1176 * SNP_INIT_EX is protected by sev_cmd_mutex, therefore this list
1177 * also needs to be protected using the same mutex.
1178 */
1179 guard(mutex)(&sev_cmd_mutex);
1180
1181 list_for_each_entry_safe(entry, nentry, &snp_hv_fixed_pages, list) {
1182 if (entry->page != page)
1183 continue;
1184
1185 /*
1186 * HV_FIXED page state cannot be changed until reboot
1187 * and they cannot be used by an SNP guest, so they cannot
1188 * be returned back to the page allocator.
1189 * Mark the pages as free internally to allow possible re-use.
1190 */
1191 if (entry->page_state == HV_FIXED) {
1192 entry->free = true;
1193 } else {
1194 __free_pages(page, entry->order);
1195 list_del(&entry->list);
1196 kfree(entry);
1197 }
1198 return;
1199 }
1200 }
1201
snp_add_hv_fixed_pages(struct sev_device * sev,struct sev_data_range_list * range_list)1202 static void snp_add_hv_fixed_pages(struct sev_device *sev, struct sev_data_range_list *range_list)
1203 {
1204 struct snp_hv_fixed_pages_entry *entry;
1205 struct sev_data_range *range;
1206 int num_elements;
1207
1208 lockdep_assert_held(&sev_cmd_mutex);
1209
1210 if (list_empty(&snp_hv_fixed_pages))
1211 return;
1212
1213 num_elements = list_count_nodes(&snp_hv_fixed_pages) +
1214 range_list->num_elements;
1215
1216 /*
1217 * Ensure the list of HV_FIXED pages that will be passed to firmware
1218 * do not exceed the page-sized argument buffer.
1219 */
1220 if (num_elements * sizeof(*range) + sizeof(*range_list) > PAGE_SIZE) {
1221 dev_warn(sev->dev, "Additional HV_Fixed pages cannot be accommodated, omitting\n");
1222 return;
1223 }
1224
1225 range = &range_list->ranges[range_list->num_elements];
1226 list_for_each_entry(entry, &snp_hv_fixed_pages, list) {
1227 range->base = page_to_pfn(entry->page) << PAGE_SHIFT;
1228 range->page_count = 1 << entry->order;
1229 range++;
1230 }
1231 range_list->num_elements = num_elements;
1232 }
1233
snp_leak_hv_fixed_pages(void)1234 static void snp_leak_hv_fixed_pages(void)
1235 {
1236 struct snp_hv_fixed_pages_entry *entry;
1237
1238 /* List is protected by sev_cmd_mutex */
1239 lockdep_assert_held(&sev_cmd_mutex);
1240
1241 if (list_empty(&snp_hv_fixed_pages))
1242 return;
1243
1244 list_for_each_entry(entry, &snp_hv_fixed_pages, list)
1245 if (entry->page_state == HV_FIXED)
1246 __snp_leak_pages(page_to_pfn(entry->page),
1247 1 << entry->order, false);
1248 }
1249
sev_is_snp_ciphertext_hiding_supported(void)1250 bool sev_is_snp_ciphertext_hiding_supported(void)
1251 {
1252 struct psp_device *psp = psp_master;
1253 struct sev_device *sev;
1254
1255 if (!psp || !psp->sev_data)
1256 return false;
1257
1258 sev = psp->sev_data;
1259
1260 /*
1261 * Feature information indicates if CipherTextHiding feature is
1262 * supported by the SEV firmware and additionally platform status
1263 * indicates if CipherTextHiding feature is enabled in the
1264 * Platform BIOS.
1265 */
1266 return ((sev->snp_feat_info_0.ecx & SNP_CIPHER_TEXT_HIDING_SUPPORTED) &&
1267 sev->snp_plat_status.ciphertext_hiding_cap);
1268 }
1269 EXPORT_SYMBOL_GPL(sev_is_snp_ciphertext_hiding_supported);
1270
snp_get_platform_data(struct sev_device * sev,int * error)1271 static int snp_get_platform_data(struct sev_device *sev, int *error)
1272 {
1273 struct sev_data_snp_feature_info snp_feat_info;
1274 struct snp_feature_info *feat_info;
1275 struct sev_data_snp_addr buf;
1276 struct page *page;
1277 int rc;
1278
1279 /*
1280 * This function is expected to be called before SNP is
1281 * initialized.
1282 */
1283 if (sev->snp_initialized)
1284 return -EINVAL;
1285
1286 buf.address = __psp_pa(&sev->snp_plat_status);
1287 rc = sev_do_cmd(SEV_CMD_SNP_PLATFORM_STATUS, &buf, error);
1288 if (rc) {
1289 dev_err(sev->dev, "SNP PLATFORM_STATUS command failed, ret = %d, error = %#x\n",
1290 rc, *error);
1291 return rc;
1292 }
1293
1294 sev->api_major = sev->snp_plat_status.api_major;
1295 sev->api_minor = sev->snp_plat_status.api_minor;
1296 sev->build = sev->snp_plat_status.build_id;
1297
1298 /*
1299 * Do feature discovery of the currently loaded firmware,
1300 * and cache feature information from CPUID 0x8000_0024,
1301 * sub-function 0.
1302 */
1303 if (!sev->snp_plat_status.feature_info)
1304 return 0;
1305
1306 /*
1307 * Use dynamically allocated structure for the SNP_FEATURE_INFO
1308 * command to ensure structure is 8-byte aligned, and does not
1309 * cross a page boundary.
1310 */
1311 page = alloc_page(GFP_KERNEL);
1312 if (!page)
1313 return -ENOMEM;
1314
1315 feat_info = page_address(page);
1316 snp_feat_info.length = sizeof(snp_feat_info);
1317 snp_feat_info.ecx_in = 0;
1318 snp_feat_info.feature_info_paddr = __psp_pa(feat_info);
1319
1320 rc = sev_do_cmd(SEV_CMD_SNP_FEATURE_INFO, &snp_feat_info, error);
1321 if (!rc)
1322 sev->snp_feat_info_0 = *feat_info;
1323 else
1324 dev_err(sev->dev, "SNP FEATURE_INFO command failed, ret = %d, error = %#x\n",
1325 rc, *error);
1326
1327 __free_page(page);
1328
1329 return rc;
1330 }
1331
snp_filter_reserved_mem_regions(struct resource * rs,void * arg)1332 static int snp_filter_reserved_mem_regions(struct resource *rs, void *arg)
1333 {
1334 struct sev_data_range_list *range_list = arg;
1335 struct sev_data_range *range = &range_list->ranges[range_list->num_elements];
1336 size_t size;
1337
1338 /*
1339 * Ensure the list of HV_FIXED pages that will be passed to firmware
1340 * do not exceed the page-sized argument buffer.
1341 */
1342 if ((range_list->num_elements * sizeof(struct sev_data_range) +
1343 sizeof(struct sev_data_range_list)) > PAGE_SIZE)
1344 return -E2BIG;
1345
1346 switch (rs->desc) {
1347 case E820_TYPE_RESERVED:
1348 case E820_TYPE_PMEM:
1349 case E820_TYPE_ACPI:
1350 range->base = rs->start & PAGE_MASK;
1351 size = PAGE_ALIGN((rs->end + 1) - rs->start);
1352 range->page_count = size >> PAGE_SHIFT;
1353 range_list->num_elements++;
1354 break;
1355 default:
1356 break;
1357 }
1358
1359 return 0;
1360 }
1361
__sev_snp_init_locked(int * error,unsigned int max_snp_asid)1362 static int __sev_snp_init_locked(int *error, unsigned int max_snp_asid)
1363 {
1364 struct psp_device *psp = psp_master;
1365 struct sev_data_snp_init_ex data;
1366 struct sev_device *sev;
1367 void *arg = &data;
1368 int cmd, rc = 0;
1369
1370 if (!cc_platform_has(CC_ATTR_HOST_SEV_SNP))
1371 return -ENODEV;
1372
1373 sev = psp->sev_data;
1374
1375 if (sev->snp_initialized)
1376 return 0;
1377
1378 if (!sev_version_greater_or_equal(SNP_MIN_API_MAJOR, SNP_MIN_API_MINOR)) {
1379 dev_dbg(sev->dev, "SEV-SNP support requires firmware version >= %d:%d\n",
1380 SNP_MIN_API_MAJOR, SNP_MIN_API_MINOR);
1381 return -EOPNOTSUPP;
1382 }
1383
1384 /* SNP_INIT requires MSR_VM_HSAVE_PA to be cleared on all CPUs. */
1385 on_each_cpu(snp_set_hsave_pa, NULL, 1);
1386
1387 /*
1388 * Starting in SNP firmware v1.52, the SNP_INIT_EX command takes a list
1389 * of system physical address ranges to convert into HV-fixed page
1390 * states during the RMP initialization. For instance, the memory that
1391 * UEFI reserves should be included in the that list. This allows system
1392 * components that occasionally write to memory (e.g. logging to UEFI
1393 * reserved regions) to not fail due to RMP initialization and SNP
1394 * enablement.
1395 *
1396 */
1397 if (sev_version_greater_or_equal(SNP_MIN_API_MAJOR, 52)) {
1398 bool tio_supp = !!(sev->snp_feat_info_0.ebx & SNP_SEV_TIO_SUPPORTED);
1399
1400 /*
1401 * Firmware checks that the pages containing the ranges enumerated
1402 * in the RANGES structure are either in the default page state or in the
1403 * firmware page state.
1404 */
1405 snp_range_list = kzalloc(PAGE_SIZE, GFP_KERNEL);
1406 if (!snp_range_list) {
1407 dev_err(sev->dev,
1408 "SEV: SNP_INIT_EX range list memory allocation failed\n");
1409 return -ENOMEM;
1410 }
1411
1412 /*
1413 * Retrieve all reserved memory regions from the e820 memory map
1414 * to be setup as HV-fixed pages.
1415 */
1416 rc = walk_iomem_res_desc(IORES_DESC_NONE, IORESOURCE_MEM, 0, ~0,
1417 snp_range_list, snp_filter_reserved_mem_regions);
1418 if (rc) {
1419 dev_err(sev->dev,
1420 "SEV: SNP_INIT_EX walk_iomem_res_desc failed rc = %d\n", rc);
1421 return rc;
1422 }
1423
1424 /*
1425 * Add HV_Fixed pages from other PSP sub-devices, such as SFS to the
1426 * HV_Fixed page list.
1427 */
1428 snp_add_hv_fixed_pages(sev, snp_range_list);
1429
1430 memset(&data, 0, sizeof(data));
1431
1432 if (max_snp_asid) {
1433 data.ciphertext_hiding_en = 1;
1434 data.max_snp_asid = max_snp_asid;
1435 }
1436
1437 data.init_rmp = 1;
1438 data.list_paddr_en = 1;
1439 data.list_paddr = __psp_pa(snp_range_list);
1440
1441 data.tio_en = tio_supp && sev_tio_enabled && amd_iommu_sev_tio_supported();
1442
1443 /*
1444 * When psp_init_on_probe is disabled, the userspace calling
1445 * SEV ioctl can inadvertently shut down SNP and SEV-TIO causing
1446 * unexpected state loss.
1447 */
1448 if (data.tio_en && !psp_init_on_probe)
1449 dev_warn(sev->dev, "SEV-TIO as incompatible with psp_init_on_probe=0\n");
1450
1451 cmd = SEV_CMD_SNP_INIT_EX;
1452 } else {
1453 cmd = SEV_CMD_SNP_INIT;
1454 arg = NULL;
1455 }
1456
1457 /*
1458 * The following sequence must be issued before launching the first SNP
1459 * guest to ensure all dirty cache lines are flushed, including from
1460 * updates to the RMP table itself via the RMPUPDATE instruction:
1461 *
1462 * - WBINVD on all running CPUs
1463 * - SEV_CMD_SNP_INIT[_EX] firmware command
1464 * - WBINVD on all running CPUs
1465 * - SEV_CMD_SNP_DF_FLUSH firmware command
1466 */
1467 wbinvd_on_all_cpus();
1468
1469 rc = __sev_do_cmd_locked(cmd, arg, error);
1470 if (rc) {
1471 dev_err(sev->dev, "SEV-SNP: %s failed rc %d, error %#x\n",
1472 cmd == SEV_CMD_SNP_INIT_EX ? "SNP_INIT_EX" : "SNP_INIT",
1473 rc, *error);
1474 return rc;
1475 }
1476
1477 /* Prepare for first SNP guest launch after INIT. */
1478 wbinvd_on_all_cpus();
1479 rc = __sev_do_cmd_locked(SEV_CMD_SNP_DF_FLUSH, NULL, error);
1480 if (rc) {
1481 dev_err(sev->dev, "SEV-SNP: SNP_DF_FLUSH failed rc %d, error %#x\n",
1482 rc, *error);
1483 return rc;
1484 }
1485
1486 snp_hv_fixed_pages_state_update(sev, HV_FIXED);
1487 sev->snp_initialized = true;
1488 dev_dbg(sev->dev, "SEV-SNP firmware initialized, SEV-TIO is %s\n",
1489 data.tio_en ? "enabled" : "disabled");
1490
1491 dev_info(sev->dev, "SEV-SNP API:%d.%d build:%d\n", sev->api_major,
1492 sev->api_minor, sev->build);
1493
1494 atomic_notifier_chain_register(&panic_notifier_list,
1495 &snp_panic_notifier);
1496
1497 if (data.tio_en) {
1498 /*
1499 * This executes with the sev_cmd_mutex held so down the stack
1500 * snp_reclaim_pages(locked=false) might be needed (which is extremely
1501 * unlikely) but will cause a deadlock.
1502 * Instead of exporting __snp_alloc_firmware_pages(), allocate a page
1503 * for this one call here.
1504 */
1505 void *tio_status = page_address(__snp_alloc_firmware_pages(
1506 GFP_KERNEL_ACCOUNT | __GFP_ZERO, 0, true));
1507
1508 if (tio_status) {
1509 sev_tsm_init_locked(sev, tio_status);
1510 __snp_free_firmware_pages(virt_to_page(tio_status), 0, true);
1511 }
1512 }
1513
1514 sev_es_tmr_size = SNP_TMR_SIZE;
1515
1516 return 0;
1517 }
1518
__sev_platform_init_handle_tmr(struct sev_device * sev)1519 static void __sev_platform_init_handle_tmr(struct sev_device *sev)
1520 {
1521 if (sev_es_tmr)
1522 return;
1523
1524 /* Obtain the TMR memory area for SEV-ES use */
1525 sev_es_tmr = sev_fw_alloc(sev_es_tmr_size);
1526 if (sev_es_tmr) {
1527 /* Must flush the cache before giving it to the firmware */
1528 if (!sev->snp_initialized)
1529 clflush_cache_range(sev_es_tmr, sev_es_tmr_size);
1530 } else {
1531 dev_warn(sev->dev, "SEV: TMR allocation failed, SEV-ES support unavailable\n");
1532 }
1533 }
1534
1535 /*
1536 * If an init_ex_path is provided allocate a buffer for the file and
1537 * read in the contents. Additionally, if SNP is initialized, convert
1538 * the buffer pages to firmware pages.
1539 */
__sev_platform_init_handle_init_ex_path(struct sev_device * sev)1540 static int __sev_platform_init_handle_init_ex_path(struct sev_device *sev)
1541 {
1542 struct page *page;
1543 int rc;
1544
1545 if (!init_ex_path)
1546 return 0;
1547
1548 if (sev_init_ex_buffer)
1549 return 0;
1550
1551 page = alloc_pages(GFP_KERNEL, get_order(NV_LENGTH));
1552 if (!page) {
1553 dev_err(sev->dev, "SEV: INIT_EX NV memory allocation failed\n");
1554 return -ENOMEM;
1555 }
1556
1557 sev_init_ex_buffer = page_address(page);
1558
1559 rc = sev_read_init_ex_file();
1560 if (rc)
1561 return rc;
1562
1563 /* If SEV-SNP is initialized, transition to firmware page. */
1564 if (sev->snp_initialized) {
1565 unsigned long npages;
1566
1567 npages = 1UL << get_order(NV_LENGTH);
1568 if (rmp_mark_pages_firmware(__pa(sev_init_ex_buffer), npages, false)) {
1569 dev_err(sev->dev, "SEV: INIT_EX NV memory page state change failed.\n");
1570 return -ENOMEM;
1571 }
1572 }
1573
1574 return 0;
1575 }
1576
__sev_platform_init_locked(int * error)1577 static int __sev_platform_init_locked(int *error)
1578 {
1579 int rc, psp_ret, dfflush_error;
1580 struct sev_device *sev;
1581
1582 psp_ret = dfflush_error = SEV_RET_NO_FW_CALL;
1583
1584 if (!psp_master || !psp_master->sev_data)
1585 return -ENODEV;
1586
1587 sev = psp_master->sev_data;
1588
1589 if (sev->sev_plat_status.state == SEV_STATE_INIT)
1590 return 0;
1591
1592 __sev_platform_init_handle_tmr(sev);
1593
1594 rc = __sev_platform_init_handle_init_ex_path(sev);
1595 if (rc)
1596 return rc;
1597
1598 rc = __sev_do_init_locked(&psp_ret);
1599 if (rc && psp_ret == SEV_RET_SECURE_DATA_INVALID) {
1600 /*
1601 * Initialization command returned an integrity check failure
1602 * status code, meaning that firmware load and validation of SEV
1603 * related persistent data has failed. Retrying the
1604 * initialization function should succeed by replacing the state
1605 * with a reset state.
1606 */
1607 dev_err(sev->dev,
1608 "SEV: retrying INIT command because of SECURE_DATA_INVALID error. Retrying once to reset PSP SEV state.");
1609 rc = __sev_do_init_locked(&psp_ret);
1610 }
1611
1612 if (error)
1613 *error = psp_ret;
1614
1615 if (rc) {
1616 dev_err(sev->dev, "SEV: %s failed %#x, rc %d\n",
1617 sev_init_ex_buffer ? "INIT_EX" : "INIT", psp_ret, rc);
1618 return rc;
1619 }
1620
1621 sev->sev_plat_status.state = SEV_STATE_INIT;
1622
1623 /* Prepare for first SEV guest launch after INIT */
1624 wbinvd_on_all_cpus();
1625 rc = __sev_do_cmd_locked(SEV_CMD_DF_FLUSH, NULL, &dfflush_error);
1626 if (rc) {
1627 dev_err(sev->dev, "SEV: DF_FLUSH failed %#x, rc %d\n",
1628 dfflush_error, rc);
1629 return rc;
1630 }
1631
1632 dev_dbg(sev->dev, "SEV firmware initialized\n");
1633
1634 dev_info(sev->dev, "SEV API:%d.%d build:%d\n", sev->api_major,
1635 sev->api_minor, sev->build);
1636
1637 return 0;
1638 }
1639
_sev_platform_init_locked(struct sev_platform_init_args * args)1640 static int _sev_platform_init_locked(struct sev_platform_init_args *args)
1641 {
1642 struct sev_device *sev;
1643 int rc;
1644
1645 if (!psp_master || !psp_master->sev_data)
1646 return -ENODEV;
1647
1648 /*
1649 * Skip SNP/SEV initialization under a kdump kernel as SEV/SNP
1650 * may already be initialized in the previous kernel. Since no
1651 * SNP/SEV guests are run under a kdump kernel, there is no
1652 * need to initialize SNP or SEV during kdump boot.
1653 */
1654 if (is_kdump_kernel())
1655 return 0;
1656
1657 sev = psp_master->sev_data;
1658
1659 if (sev->sev_plat_status.state == SEV_STATE_INIT)
1660 return 0;
1661
1662 rc = __sev_snp_init_locked(&args->error, args->max_snp_asid);
1663 if (rc && rc != -ENODEV)
1664 return rc;
1665
1666 /* Defer legacy SEV/SEV-ES support if allowed by caller/module. */
1667 if (args->probe && !psp_init_on_probe)
1668 return 0;
1669
1670 return __sev_platform_init_locked(&args->error);
1671 }
1672
sev_platform_init(struct sev_platform_init_args * args)1673 int sev_platform_init(struct sev_platform_init_args *args)
1674 {
1675 int rc;
1676
1677 mutex_lock(&sev_cmd_mutex);
1678 rc = _sev_platform_init_locked(args);
1679 mutex_unlock(&sev_cmd_mutex);
1680
1681 return rc;
1682 }
1683 EXPORT_SYMBOL_GPL(sev_platform_init);
1684
__sev_platform_shutdown_locked(int * error)1685 static int __sev_platform_shutdown_locked(int *error)
1686 {
1687 struct psp_device *psp = psp_master;
1688 struct sev_device *sev;
1689 int ret;
1690
1691 if (!psp || !psp->sev_data)
1692 return 0;
1693
1694 sev = psp->sev_data;
1695
1696 if (sev->sev_plat_status.state == SEV_STATE_UNINIT)
1697 return 0;
1698
1699 ret = __sev_do_cmd_locked(SEV_CMD_SHUTDOWN, NULL, error);
1700 if (ret) {
1701 dev_err(sev->dev, "SEV: failed to SHUTDOWN error %#x, rc %d\n",
1702 *error, ret);
1703 return ret;
1704 }
1705
1706 sev->sev_plat_status.state = SEV_STATE_UNINIT;
1707 dev_dbg(sev->dev, "SEV firmware shutdown\n");
1708
1709 return ret;
1710 }
1711
sev_get_platform_state(int * state,int * error)1712 static int sev_get_platform_state(int *state, int *error)
1713 {
1714 struct sev_user_data_status data;
1715 int rc;
1716
1717 rc = __sev_do_cmd_locked(SEV_CMD_PLATFORM_STATUS, &data, error);
1718 if (rc)
1719 return rc;
1720
1721 *state = data.state;
1722 return rc;
1723 }
1724
sev_move_to_init_state(struct sev_issue_cmd * argp,bool * shutdown_required)1725 static int sev_move_to_init_state(struct sev_issue_cmd *argp, bool *shutdown_required)
1726 {
1727 struct sev_platform_init_args init_args = {0};
1728 int rc;
1729
1730 rc = _sev_platform_init_locked(&init_args);
1731 if (rc) {
1732 argp->error = SEV_RET_INVALID_PLATFORM_STATE;
1733 return rc;
1734 }
1735
1736 *shutdown_required = true;
1737
1738 return 0;
1739 }
1740
snp_move_to_init_state(struct sev_issue_cmd * argp,bool * shutdown_required)1741 static int snp_move_to_init_state(struct sev_issue_cmd *argp, bool *shutdown_required)
1742 {
1743 int error, rc;
1744
1745 rc = __sev_snp_init_locked(&error, 0);
1746 if (rc) {
1747 argp->error = SEV_RET_INVALID_PLATFORM_STATE;
1748 return rc;
1749 }
1750
1751 *shutdown_required = true;
1752
1753 return 0;
1754 }
1755
sev_ioctl_do_reset(struct sev_issue_cmd * argp,bool writable)1756 static int sev_ioctl_do_reset(struct sev_issue_cmd *argp, bool writable)
1757 {
1758 int state, rc;
1759
1760 if (!writable)
1761 return -EPERM;
1762
1763 /*
1764 * The SEV spec requires that FACTORY_RESET must be issued in
1765 * UNINIT state. Before we go further lets check if any guest is
1766 * active.
1767 *
1768 * If FW is in WORKING state then deny the request otherwise issue
1769 * SHUTDOWN command do INIT -> UNINIT before issuing the FACTORY_RESET.
1770 *
1771 */
1772 rc = sev_get_platform_state(&state, &argp->error);
1773 if (rc)
1774 return rc;
1775
1776 if (state == SEV_STATE_WORKING)
1777 return -EBUSY;
1778
1779 if (state == SEV_STATE_INIT) {
1780 rc = __sev_platform_shutdown_locked(&argp->error);
1781 if (rc)
1782 return rc;
1783 }
1784
1785 return __sev_do_cmd_locked(SEV_CMD_FACTORY_RESET, NULL, &argp->error);
1786 }
1787
sev_ioctl_do_platform_status(struct sev_issue_cmd * argp)1788 static int sev_ioctl_do_platform_status(struct sev_issue_cmd *argp)
1789 {
1790 struct sev_user_data_status data;
1791 int ret;
1792
1793 memset(&data, 0, sizeof(data));
1794
1795 ret = __sev_do_cmd_locked(SEV_CMD_PLATFORM_STATUS, &data, &argp->error);
1796 if (ret)
1797 return ret;
1798
1799 if (copy_to_user((void __user *)argp->data, &data, sizeof(data)))
1800 ret = -EFAULT;
1801
1802 return ret;
1803 }
1804
sev_ioctl_do_pek_pdh_gen(int cmd,struct sev_issue_cmd * argp,bool writable)1805 static int sev_ioctl_do_pek_pdh_gen(int cmd, struct sev_issue_cmd *argp, bool writable)
1806 {
1807 struct sev_device *sev = psp_master->sev_data;
1808 bool shutdown_required = false;
1809 int rc;
1810
1811 if (!writable)
1812 return -EPERM;
1813
1814 if (sev->sev_plat_status.state == SEV_STATE_UNINIT) {
1815 rc = sev_move_to_init_state(argp, &shutdown_required);
1816 if (rc)
1817 return rc;
1818 }
1819
1820 rc = __sev_do_cmd_locked(cmd, NULL, &argp->error);
1821
1822 if (shutdown_required)
1823 __sev_firmware_shutdown(sev, false);
1824
1825 return rc;
1826 }
1827
sev_ioctl_do_pek_csr(struct sev_issue_cmd * argp,bool writable)1828 static int sev_ioctl_do_pek_csr(struct sev_issue_cmd *argp, bool writable)
1829 {
1830 struct sev_device *sev = psp_master->sev_data;
1831 struct sev_user_data_pek_csr input;
1832 bool shutdown_required = false;
1833 struct sev_data_pek_csr data;
1834 void __user *input_address;
1835 void *blob = NULL;
1836 int ret;
1837
1838 if (!writable)
1839 return -EPERM;
1840
1841 if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
1842 return -EFAULT;
1843
1844 memset(&data, 0, sizeof(data));
1845
1846 /* userspace wants to query CSR length */
1847 if (!input.address || !input.length)
1848 goto cmd;
1849
1850 /* allocate a physically contiguous buffer to store the CSR blob */
1851 input_address = (void __user *)input.address;
1852 if (input.length > SEV_FW_BLOB_MAX_SIZE)
1853 return -EFAULT;
1854
1855 blob = kzalloc(input.length, GFP_KERNEL);
1856 if (!blob)
1857 return -ENOMEM;
1858
1859 data.address = __psp_pa(blob);
1860 data.len = input.length;
1861
1862 cmd:
1863 if (sev->sev_plat_status.state == SEV_STATE_UNINIT) {
1864 ret = sev_move_to_init_state(argp, &shutdown_required);
1865 if (ret)
1866 goto e_free_blob;
1867 }
1868
1869 ret = __sev_do_cmd_locked(SEV_CMD_PEK_CSR, &data, &argp->error);
1870
1871 /* If we query the CSR length, FW responded with expected data. */
1872 input.length = data.len;
1873
1874 if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) {
1875 ret = -EFAULT;
1876 goto e_free_blob;
1877 }
1878
1879 if (blob) {
1880 if (copy_to_user(input_address, blob, input.length))
1881 ret = -EFAULT;
1882 }
1883
1884 e_free_blob:
1885 if (shutdown_required)
1886 __sev_firmware_shutdown(sev, false);
1887
1888 kfree(blob);
1889 return ret;
1890 }
1891
psp_copy_user_blob(u64 uaddr,u32 len)1892 void *psp_copy_user_blob(u64 uaddr, u32 len)
1893 {
1894 if (!uaddr || !len)
1895 return ERR_PTR(-EINVAL);
1896
1897 /* verify that blob length does not exceed our limit */
1898 if (len > SEV_FW_BLOB_MAX_SIZE)
1899 return ERR_PTR(-EINVAL);
1900
1901 return memdup_user((void __user *)uaddr, len);
1902 }
1903 EXPORT_SYMBOL_GPL(psp_copy_user_blob);
1904
sev_get_api_version(void)1905 static int sev_get_api_version(void)
1906 {
1907 struct sev_device *sev = psp_master->sev_data;
1908 struct sev_user_data_status status;
1909 int error = 0, ret;
1910
1911 /*
1912 * Cache SNP platform status and SNP feature information
1913 * if SNP is available.
1914 */
1915 if (cc_platform_has(CC_ATTR_HOST_SEV_SNP)) {
1916 ret = snp_get_platform_data(sev, &error);
1917 if (ret)
1918 return 1;
1919 }
1920
1921 ret = sev_platform_status(&status, &error);
1922 if (ret) {
1923 dev_err(sev->dev,
1924 "SEV: failed to get status. Error: %#x\n", error);
1925 return 1;
1926 }
1927
1928 /* Cache SEV platform status */
1929 sev->sev_plat_status = status;
1930
1931 sev->api_major = status.api_major;
1932 sev->api_minor = status.api_minor;
1933 sev->build = status.build;
1934
1935 return 0;
1936 }
1937
sev_get_firmware(struct device * dev,const struct firmware ** firmware)1938 static int sev_get_firmware(struct device *dev,
1939 const struct firmware **firmware)
1940 {
1941 char fw_name_specific[SEV_FW_NAME_SIZE];
1942 char fw_name_subset[SEV_FW_NAME_SIZE];
1943
1944 snprintf(fw_name_specific, sizeof(fw_name_specific),
1945 "amd/amd_sev_fam%.2xh_model%.2xh.sbin",
1946 boot_cpu_data.x86, boot_cpu_data.x86_model);
1947
1948 snprintf(fw_name_subset, sizeof(fw_name_subset),
1949 "amd/amd_sev_fam%.2xh_model%.1xxh.sbin",
1950 boot_cpu_data.x86, (boot_cpu_data.x86_model & 0xf0) >> 4);
1951
1952 /* Check for SEV FW for a particular model.
1953 * Ex. amd_sev_fam17h_model00h.sbin for Family 17h Model 00h
1954 *
1955 * or
1956 *
1957 * Check for SEV FW common to a subset of models.
1958 * Ex. amd_sev_fam17h_model0xh.sbin for
1959 * Family 17h Model 00h -- Family 17h Model 0Fh
1960 *
1961 * or
1962 *
1963 * Fall-back to using generic name: sev.fw
1964 */
1965 if ((firmware_request_nowarn(firmware, fw_name_specific, dev) >= 0) ||
1966 (firmware_request_nowarn(firmware, fw_name_subset, dev) >= 0) ||
1967 (firmware_request_nowarn(firmware, SEV_FW_FILE, dev) >= 0))
1968 return 0;
1969
1970 return -ENOENT;
1971 }
1972
1973 /* Don't fail if SEV FW couldn't be updated. Continue with existing SEV FW */
sev_update_firmware(struct device * dev)1974 static int sev_update_firmware(struct device *dev)
1975 {
1976 struct sev_data_download_firmware *data;
1977 const struct firmware *firmware;
1978 int ret, error, order;
1979 struct page *p;
1980 u64 data_size;
1981
1982 if (!sev_version_greater_or_equal(0, 15)) {
1983 dev_dbg(dev, "DOWNLOAD_FIRMWARE not supported\n");
1984 return -1;
1985 }
1986
1987 if (sev_get_firmware(dev, &firmware) == -ENOENT) {
1988 dev_dbg(dev, "No SEV firmware file present\n");
1989 return -1;
1990 }
1991
1992 /*
1993 * SEV FW expects the physical address given to it to be 32
1994 * byte aligned. Memory allocated has structure placed at the
1995 * beginning followed by the firmware being passed to the SEV
1996 * FW. Allocate enough memory for data structure + alignment
1997 * padding + SEV FW.
1998 */
1999 data_size = ALIGN(sizeof(struct sev_data_download_firmware), 32);
2000
2001 order = get_order(firmware->size + data_size);
2002 p = alloc_pages(GFP_KERNEL, order);
2003 if (!p) {
2004 ret = -1;
2005 goto fw_err;
2006 }
2007
2008 /*
2009 * Copy firmware data to a kernel allocated contiguous
2010 * memory region.
2011 */
2012 data = page_address(p);
2013 memcpy(page_address(p) + data_size, firmware->data, firmware->size);
2014
2015 data->address = __psp_pa(page_address(p) + data_size);
2016 data->len = firmware->size;
2017
2018 ret = sev_do_cmd(SEV_CMD_DOWNLOAD_FIRMWARE, data, &error);
2019
2020 /*
2021 * A quirk for fixing the committed TCB version, when upgrading from
2022 * earlier firmware version than 1.50.
2023 */
2024 if (!ret && !sev_version_greater_or_equal(1, 50))
2025 ret = sev_do_cmd(SEV_CMD_DOWNLOAD_FIRMWARE, data, &error);
2026
2027 if (ret)
2028 dev_dbg(dev, "Failed to update SEV firmware: %#x\n", error);
2029
2030 __free_pages(p, order);
2031
2032 fw_err:
2033 release_firmware(firmware);
2034
2035 return ret;
2036 }
2037
__sev_snp_shutdown_locked(int * error,bool panic)2038 static int __sev_snp_shutdown_locked(int *error, bool panic)
2039 {
2040 struct psp_device *psp = psp_master;
2041 struct sev_device *sev;
2042 struct sev_data_snp_shutdown_ex data;
2043 int ret;
2044
2045 if (!psp || !psp->sev_data)
2046 return 0;
2047
2048 sev = psp->sev_data;
2049
2050 if (!sev->snp_initialized)
2051 return 0;
2052
2053 memset(&data, 0, sizeof(data));
2054 data.len = sizeof(data);
2055 data.iommu_snp_shutdown = 1;
2056
2057 /*
2058 * If invoked during panic handling, local interrupts are disabled
2059 * and all CPUs are stopped, so wbinvd_on_all_cpus() can't be called.
2060 * In that case, a wbinvd() is done on remote CPUs via the NMI
2061 * callback, so only a local wbinvd() is needed here.
2062 */
2063 if (!panic)
2064 wbinvd_on_all_cpus();
2065 else
2066 wbinvd();
2067
2068 ret = __sev_do_cmd_locked(SEV_CMD_SNP_SHUTDOWN_EX, &data, error);
2069 /* SHUTDOWN may require DF_FLUSH */
2070 if (*error == SEV_RET_DFFLUSH_REQUIRED) {
2071 int dfflush_error = SEV_RET_NO_FW_CALL;
2072
2073 ret = __sev_do_cmd_locked(SEV_CMD_SNP_DF_FLUSH, NULL, &dfflush_error);
2074 if (ret) {
2075 dev_err(sev->dev, "SEV-SNP DF_FLUSH failed, ret = %d, error = %#x\n",
2076 ret, dfflush_error);
2077 return ret;
2078 }
2079 /* reissue the shutdown command */
2080 ret = __sev_do_cmd_locked(SEV_CMD_SNP_SHUTDOWN_EX, &data,
2081 error);
2082 }
2083 if (ret) {
2084 dev_err(sev->dev, "SEV-SNP firmware shutdown failed, rc %d, error %#x\n",
2085 ret, *error);
2086 return ret;
2087 }
2088
2089 /*
2090 * SNP_SHUTDOWN_EX with IOMMU_SNP_SHUTDOWN set to 1 disables SNP
2091 * enforcement by the IOMMU and also transitions all pages
2092 * associated with the IOMMU to the Reclaim state.
2093 * Firmware was transitioning the IOMMU pages to Hypervisor state
2094 * before version 1.53. But, accounting for the number of assigned
2095 * 4kB pages in a 2M page was done incorrectly by not transitioning
2096 * to the Reclaim state. This resulted in RMP #PF when later accessing
2097 * the 2M page containing those pages during kexec boot. Hence, the
2098 * firmware now transitions these pages to Reclaim state and hypervisor
2099 * needs to transition these pages to shared state. SNP Firmware
2100 * version 1.53 and above are needed for kexec boot.
2101 */
2102 ret = amd_iommu_snp_disable();
2103 if (ret) {
2104 dev_err(sev->dev, "SNP IOMMU shutdown failed\n");
2105 return ret;
2106 }
2107
2108 snp_leak_hv_fixed_pages();
2109 sev->snp_initialized = false;
2110 dev_dbg(sev->dev, "SEV-SNP firmware shutdown\n");
2111
2112 /*
2113 * __sev_snp_shutdown_locked() deadlocks when it tries to unregister
2114 * itself during panic as the panic notifier is called with RCU read
2115 * lock held and notifier unregistration does RCU synchronization.
2116 */
2117 if (!panic)
2118 atomic_notifier_chain_unregister(&panic_notifier_list,
2119 &snp_panic_notifier);
2120
2121 /* Reset TMR size back to default */
2122 sev_es_tmr_size = SEV_TMR_SIZE;
2123
2124 return ret;
2125 }
2126
sev_ioctl_do_pek_import(struct sev_issue_cmd * argp,bool writable)2127 static int sev_ioctl_do_pek_import(struct sev_issue_cmd *argp, bool writable)
2128 {
2129 struct sev_device *sev = psp_master->sev_data;
2130 struct sev_user_data_pek_cert_import input;
2131 struct sev_data_pek_cert_import data;
2132 bool shutdown_required = false;
2133 void *pek_blob, *oca_blob;
2134 int ret;
2135
2136 if (!writable)
2137 return -EPERM;
2138
2139 if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
2140 return -EFAULT;
2141
2142 /* copy PEK certificate blobs from userspace */
2143 pek_blob = psp_copy_user_blob(input.pek_cert_address, input.pek_cert_len);
2144 if (IS_ERR(pek_blob))
2145 return PTR_ERR(pek_blob);
2146
2147 data.reserved = 0;
2148 data.pek_cert_address = __psp_pa(pek_blob);
2149 data.pek_cert_len = input.pek_cert_len;
2150
2151 /* copy PEK certificate blobs from userspace */
2152 oca_blob = psp_copy_user_blob(input.oca_cert_address, input.oca_cert_len);
2153 if (IS_ERR(oca_blob)) {
2154 ret = PTR_ERR(oca_blob);
2155 goto e_free_pek;
2156 }
2157
2158 data.oca_cert_address = __psp_pa(oca_blob);
2159 data.oca_cert_len = input.oca_cert_len;
2160
2161 /* If platform is not in INIT state then transition it to INIT */
2162 if (sev->sev_plat_status.state != SEV_STATE_INIT) {
2163 ret = sev_move_to_init_state(argp, &shutdown_required);
2164 if (ret)
2165 goto e_free_oca;
2166 }
2167
2168 ret = __sev_do_cmd_locked(SEV_CMD_PEK_CERT_IMPORT, &data, &argp->error);
2169
2170 e_free_oca:
2171 if (shutdown_required)
2172 __sev_firmware_shutdown(sev, false);
2173
2174 kfree(oca_blob);
2175 e_free_pek:
2176 kfree(pek_blob);
2177 return ret;
2178 }
2179
sev_ioctl_do_get_id2(struct sev_issue_cmd * argp)2180 static int sev_ioctl_do_get_id2(struct sev_issue_cmd *argp)
2181 {
2182 struct sev_user_data_get_id2 input;
2183 struct sev_data_get_id data;
2184 void __user *input_address;
2185 void *id_blob = NULL;
2186 int ret;
2187
2188 /* SEV GET_ID is available from SEV API v0.16 and up */
2189 if (!sev_version_greater_or_equal(0, 16))
2190 return -ENOTSUPP;
2191
2192 if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
2193 return -EFAULT;
2194
2195 input_address = (void __user *)input.address;
2196
2197 if (input.address && input.length) {
2198 /*
2199 * The length of the ID shouldn't be assumed by software since
2200 * it may change in the future. The allocation size is limited
2201 * to 1 << (PAGE_SHIFT + MAX_PAGE_ORDER) by the page allocator.
2202 * If the allocation fails, simply return ENOMEM rather than
2203 * warning in the kernel log.
2204 */
2205 id_blob = kzalloc(input.length, GFP_KERNEL | __GFP_NOWARN);
2206 if (!id_blob)
2207 return -ENOMEM;
2208
2209 data.address = __psp_pa(id_blob);
2210 data.len = input.length;
2211 } else {
2212 data.address = 0;
2213 data.len = 0;
2214 }
2215
2216 ret = __sev_do_cmd_locked(SEV_CMD_GET_ID, &data, &argp->error);
2217
2218 /*
2219 * Firmware will return the length of the ID value (either the minimum
2220 * required length or the actual length written), return it to the user.
2221 */
2222 input.length = data.len;
2223
2224 if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) {
2225 ret = -EFAULT;
2226 goto e_free;
2227 }
2228
2229 if (id_blob) {
2230 if (copy_to_user(input_address, id_blob, data.len)) {
2231 ret = -EFAULT;
2232 goto e_free;
2233 }
2234 }
2235
2236 e_free:
2237 kfree(id_blob);
2238
2239 return ret;
2240 }
2241
sev_ioctl_do_get_id(struct sev_issue_cmd * argp)2242 static int sev_ioctl_do_get_id(struct sev_issue_cmd *argp)
2243 {
2244 struct sev_data_get_id *data;
2245 u64 data_size, user_size;
2246 void *id_blob, *mem;
2247 int ret;
2248
2249 /* SEV GET_ID available from SEV API v0.16 and up */
2250 if (!sev_version_greater_or_equal(0, 16))
2251 return -ENOTSUPP;
2252
2253 /* SEV FW expects the buffer it fills with the ID to be
2254 * 8-byte aligned. Memory allocated should be enough to
2255 * hold data structure + alignment padding + memory
2256 * where SEV FW writes the ID.
2257 */
2258 data_size = ALIGN(sizeof(struct sev_data_get_id), 8);
2259 user_size = sizeof(struct sev_user_data_get_id);
2260
2261 mem = kzalloc(data_size + user_size, GFP_KERNEL);
2262 if (!mem)
2263 return -ENOMEM;
2264
2265 data = mem;
2266 id_blob = mem + data_size;
2267
2268 data->address = __psp_pa(id_blob);
2269 data->len = user_size;
2270
2271 ret = __sev_do_cmd_locked(SEV_CMD_GET_ID, data, &argp->error);
2272 if (!ret) {
2273 if (copy_to_user((void __user *)argp->data, id_blob, data->len))
2274 ret = -EFAULT;
2275 }
2276
2277 kfree(mem);
2278
2279 return ret;
2280 }
2281
sev_ioctl_do_pdh_export(struct sev_issue_cmd * argp,bool writable)2282 static int sev_ioctl_do_pdh_export(struct sev_issue_cmd *argp, bool writable)
2283 {
2284 struct sev_device *sev = psp_master->sev_data;
2285 struct sev_user_data_pdh_cert_export input;
2286 void *pdh_blob = NULL, *cert_blob = NULL;
2287 struct sev_data_pdh_cert_export data;
2288 void __user *input_cert_chain_address;
2289 void __user *input_pdh_cert_address;
2290 bool shutdown_required = false;
2291 int ret;
2292
2293 if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
2294 return -EFAULT;
2295
2296 memset(&data, 0, sizeof(data));
2297
2298 input_pdh_cert_address = (void __user *)input.pdh_cert_address;
2299 input_cert_chain_address = (void __user *)input.cert_chain_address;
2300
2301 /* Userspace wants to query the certificate length. */
2302 if (!input.pdh_cert_address ||
2303 !input.pdh_cert_len ||
2304 !input.cert_chain_address)
2305 goto cmd;
2306
2307 /* Allocate a physically contiguous buffer to store the PDH blob. */
2308 if (input.pdh_cert_len > SEV_FW_BLOB_MAX_SIZE)
2309 return -EFAULT;
2310
2311 /* Allocate a physically contiguous buffer to store the cert chain blob. */
2312 if (input.cert_chain_len > SEV_FW_BLOB_MAX_SIZE)
2313 return -EFAULT;
2314
2315 pdh_blob = kzalloc(input.pdh_cert_len, GFP_KERNEL);
2316 if (!pdh_blob)
2317 return -ENOMEM;
2318
2319 data.pdh_cert_address = __psp_pa(pdh_blob);
2320 data.pdh_cert_len = input.pdh_cert_len;
2321
2322 cert_blob = kzalloc(input.cert_chain_len, GFP_KERNEL);
2323 if (!cert_blob) {
2324 ret = -ENOMEM;
2325 goto e_free_pdh;
2326 }
2327
2328 data.cert_chain_address = __psp_pa(cert_blob);
2329 data.cert_chain_len = input.cert_chain_len;
2330
2331 cmd:
2332 /* If platform is not in INIT state then transition it to INIT. */
2333 if (sev->sev_plat_status.state != SEV_STATE_INIT) {
2334 if (!writable) {
2335 ret = -EPERM;
2336 goto e_free_cert;
2337 }
2338 ret = sev_move_to_init_state(argp, &shutdown_required);
2339 if (ret)
2340 goto e_free_cert;
2341 }
2342
2343 ret = __sev_do_cmd_locked(SEV_CMD_PDH_CERT_EXPORT, &data, &argp->error);
2344
2345 /* If we query the length, FW responded with expected data. */
2346 input.cert_chain_len = data.cert_chain_len;
2347 input.pdh_cert_len = data.pdh_cert_len;
2348
2349 if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) {
2350 ret = -EFAULT;
2351 goto e_free_cert;
2352 }
2353
2354 if (pdh_blob) {
2355 if (copy_to_user(input_pdh_cert_address,
2356 pdh_blob, input.pdh_cert_len)) {
2357 ret = -EFAULT;
2358 goto e_free_cert;
2359 }
2360 }
2361
2362 if (cert_blob) {
2363 if (copy_to_user(input_cert_chain_address,
2364 cert_blob, input.cert_chain_len))
2365 ret = -EFAULT;
2366 }
2367
2368 e_free_cert:
2369 if (shutdown_required)
2370 __sev_firmware_shutdown(sev, false);
2371
2372 kfree(cert_blob);
2373 e_free_pdh:
2374 kfree(pdh_blob);
2375 return ret;
2376 }
2377
sev_ioctl_do_snp_platform_status(struct sev_issue_cmd * argp)2378 static int sev_ioctl_do_snp_platform_status(struct sev_issue_cmd *argp)
2379 {
2380 struct sev_device *sev = psp_master->sev_data;
2381 bool shutdown_required = false;
2382 struct sev_data_snp_addr buf;
2383 struct page *status_page;
2384 int ret, error;
2385 void *data;
2386
2387 if (!argp->data)
2388 return -EINVAL;
2389
2390 status_page = alloc_page(GFP_KERNEL_ACCOUNT);
2391 if (!status_page)
2392 return -ENOMEM;
2393
2394 data = page_address(status_page);
2395
2396 if (!sev->snp_initialized) {
2397 ret = snp_move_to_init_state(argp, &shutdown_required);
2398 if (ret)
2399 goto cleanup;
2400 }
2401
2402 /*
2403 * Firmware expects status page to be in firmware-owned state, otherwise
2404 * it will report firmware error code INVALID_PAGE_STATE (0x1A).
2405 */
2406 if (rmp_mark_pages_firmware(__pa(data), 1, true)) {
2407 ret = -EFAULT;
2408 goto cleanup;
2409 }
2410
2411 buf.address = __psp_pa(data);
2412 ret = __sev_do_cmd_locked(SEV_CMD_SNP_PLATFORM_STATUS, &buf, &argp->error);
2413
2414 /*
2415 * Status page will be transitioned to Reclaim state upon success, or
2416 * left in Firmware state in failure. Use snp_reclaim_pages() to
2417 * transition either case back to Hypervisor-owned state.
2418 */
2419 if (snp_reclaim_pages(__pa(data), 1, true))
2420 return -EFAULT;
2421
2422 if (ret)
2423 goto cleanup;
2424
2425 if (copy_to_user((void __user *)argp->data, data,
2426 sizeof(struct sev_user_data_snp_status)))
2427 ret = -EFAULT;
2428
2429 cleanup:
2430 if (shutdown_required)
2431 __sev_snp_shutdown_locked(&error, false);
2432
2433 __free_pages(status_page, 0);
2434 return ret;
2435 }
2436
sev_ioctl_do_snp_commit(struct sev_issue_cmd * argp)2437 static int sev_ioctl_do_snp_commit(struct sev_issue_cmd *argp)
2438 {
2439 struct sev_device *sev = psp_master->sev_data;
2440 struct sev_data_snp_commit buf;
2441 bool shutdown_required = false;
2442 int ret, error;
2443
2444 if (!sev->snp_initialized) {
2445 ret = snp_move_to_init_state(argp, &shutdown_required);
2446 if (ret)
2447 return ret;
2448 }
2449
2450 buf.len = sizeof(buf);
2451
2452 ret = __sev_do_cmd_locked(SEV_CMD_SNP_COMMIT, &buf, &argp->error);
2453
2454 if (shutdown_required)
2455 __sev_snp_shutdown_locked(&error, false);
2456
2457 return ret;
2458 }
2459
sev_ioctl_do_snp_set_config(struct sev_issue_cmd * argp,bool writable)2460 static int sev_ioctl_do_snp_set_config(struct sev_issue_cmd *argp, bool writable)
2461 {
2462 struct sev_device *sev = psp_master->sev_data;
2463 struct sev_user_data_snp_config config;
2464 bool shutdown_required = false;
2465 int ret, error;
2466
2467 if (!argp->data)
2468 return -EINVAL;
2469
2470 if (!writable)
2471 return -EPERM;
2472
2473 if (copy_from_user(&config, (void __user *)argp->data, sizeof(config)))
2474 return -EFAULT;
2475
2476 if (!sev->snp_initialized) {
2477 ret = snp_move_to_init_state(argp, &shutdown_required);
2478 if (ret)
2479 return ret;
2480 }
2481
2482 ret = __sev_do_cmd_locked(SEV_CMD_SNP_CONFIG, &config, &argp->error);
2483
2484 if (shutdown_required)
2485 __sev_snp_shutdown_locked(&error, false);
2486
2487 return ret;
2488 }
2489
sev_ioctl_do_snp_vlek_load(struct sev_issue_cmd * argp,bool writable)2490 static int sev_ioctl_do_snp_vlek_load(struct sev_issue_cmd *argp, bool writable)
2491 {
2492 struct sev_device *sev = psp_master->sev_data;
2493 struct sev_user_data_snp_vlek_load input;
2494 bool shutdown_required = false;
2495 int ret, error;
2496 void *blob;
2497
2498 if (!argp->data)
2499 return -EINVAL;
2500
2501 if (!writable)
2502 return -EPERM;
2503
2504 if (copy_from_user(&input, u64_to_user_ptr(argp->data), sizeof(input)))
2505 return -EFAULT;
2506
2507 if (input.len != sizeof(input) || input.vlek_wrapped_version != 0)
2508 return -EINVAL;
2509
2510 blob = psp_copy_user_blob(input.vlek_wrapped_address,
2511 sizeof(struct sev_user_data_snp_wrapped_vlek_hashstick));
2512 if (IS_ERR(blob))
2513 return PTR_ERR(blob);
2514
2515 input.vlek_wrapped_address = __psp_pa(blob);
2516
2517 if (!sev->snp_initialized) {
2518 ret = snp_move_to_init_state(argp, &shutdown_required);
2519 if (ret)
2520 goto cleanup;
2521 }
2522
2523 ret = __sev_do_cmd_locked(SEV_CMD_SNP_VLEK_LOAD, &input, &argp->error);
2524
2525 if (shutdown_required)
2526 __sev_snp_shutdown_locked(&error, false);
2527
2528 cleanup:
2529 kfree(blob);
2530
2531 return ret;
2532 }
2533
sev_ioctl(struct file * file,unsigned int ioctl,unsigned long arg)2534 static long sev_ioctl(struct file *file, unsigned int ioctl, unsigned long arg)
2535 {
2536 void __user *argp = (void __user *)arg;
2537 struct sev_issue_cmd input;
2538 int ret = -EFAULT;
2539 bool writable = file->f_mode & FMODE_WRITE;
2540
2541 if (!psp_master || !psp_master->sev_data)
2542 return -ENODEV;
2543
2544 if (ioctl != SEV_ISSUE_CMD)
2545 return -EINVAL;
2546
2547 if (copy_from_user(&input, argp, sizeof(struct sev_issue_cmd)))
2548 return -EFAULT;
2549
2550 if (input.cmd > SEV_MAX)
2551 return -EINVAL;
2552
2553 mutex_lock(&sev_cmd_mutex);
2554
2555 switch (input.cmd) {
2556
2557 case SEV_FACTORY_RESET:
2558 ret = sev_ioctl_do_reset(&input, writable);
2559 break;
2560 case SEV_PLATFORM_STATUS:
2561 ret = sev_ioctl_do_platform_status(&input);
2562 break;
2563 case SEV_PEK_GEN:
2564 ret = sev_ioctl_do_pek_pdh_gen(SEV_CMD_PEK_GEN, &input, writable);
2565 break;
2566 case SEV_PDH_GEN:
2567 ret = sev_ioctl_do_pek_pdh_gen(SEV_CMD_PDH_GEN, &input, writable);
2568 break;
2569 case SEV_PEK_CSR:
2570 ret = sev_ioctl_do_pek_csr(&input, writable);
2571 break;
2572 case SEV_PEK_CERT_IMPORT:
2573 ret = sev_ioctl_do_pek_import(&input, writable);
2574 break;
2575 case SEV_PDH_CERT_EXPORT:
2576 ret = sev_ioctl_do_pdh_export(&input, writable);
2577 break;
2578 case SEV_GET_ID:
2579 pr_warn_once("SEV_GET_ID command is deprecated, use SEV_GET_ID2\n");
2580 ret = sev_ioctl_do_get_id(&input);
2581 break;
2582 case SEV_GET_ID2:
2583 ret = sev_ioctl_do_get_id2(&input);
2584 break;
2585 case SNP_PLATFORM_STATUS:
2586 ret = sev_ioctl_do_snp_platform_status(&input);
2587 break;
2588 case SNP_COMMIT:
2589 ret = sev_ioctl_do_snp_commit(&input);
2590 break;
2591 case SNP_SET_CONFIG:
2592 ret = sev_ioctl_do_snp_set_config(&input, writable);
2593 break;
2594 case SNP_VLEK_LOAD:
2595 ret = sev_ioctl_do_snp_vlek_load(&input, writable);
2596 break;
2597 default:
2598 ret = -EINVAL;
2599 goto out;
2600 }
2601
2602 if (copy_to_user(argp, &input, sizeof(struct sev_issue_cmd)))
2603 ret = -EFAULT;
2604 out:
2605 mutex_unlock(&sev_cmd_mutex);
2606
2607 return ret;
2608 }
2609
2610 static const struct file_operations sev_fops = {
2611 .owner = THIS_MODULE,
2612 .unlocked_ioctl = sev_ioctl,
2613 };
2614
sev_platform_status(struct sev_user_data_status * data,int * error)2615 int sev_platform_status(struct sev_user_data_status *data, int *error)
2616 {
2617 return sev_do_cmd(SEV_CMD_PLATFORM_STATUS, data, error);
2618 }
2619 EXPORT_SYMBOL_GPL(sev_platform_status);
2620
sev_guest_deactivate(struct sev_data_deactivate * data,int * error)2621 int sev_guest_deactivate(struct sev_data_deactivate *data, int *error)
2622 {
2623 return sev_do_cmd(SEV_CMD_DEACTIVATE, data, error);
2624 }
2625 EXPORT_SYMBOL_GPL(sev_guest_deactivate);
2626
sev_guest_activate(struct sev_data_activate * data,int * error)2627 int sev_guest_activate(struct sev_data_activate *data, int *error)
2628 {
2629 return sev_do_cmd(SEV_CMD_ACTIVATE, data, error);
2630 }
2631 EXPORT_SYMBOL_GPL(sev_guest_activate);
2632
sev_guest_decommission(struct sev_data_decommission * data,int * error)2633 int sev_guest_decommission(struct sev_data_decommission *data, int *error)
2634 {
2635 return sev_do_cmd(SEV_CMD_DECOMMISSION, data, error);
2636 }
2637 EXPORT_SYMBOL_GPL(sev_guest_decommission);
2638
sev_guest_df_flush(int * error)2639 int sev_guest_df_flush(int *error)
2640 {
2641 return sev_do_cmd(SEV_CMD_DF_FLUSH, NULL, error);
2642 }
2643 EXPORT_SYMBOL_GPL(sev_guest_df_flush);
2644
sev_exit(struct kref * ref)2645 static void sev_exit(struct kref *ref)
2646 {
2647 misc_deregister(&misc_dev->misc);
2648 kfree(misc_dev);
2649 misc_dev = NULL;
2650 }
2651
sev_misc_init(struct sev_device * sev)2652 static int sev_misc_init(struct sev_device *sev)
2653 {
2654 struct device *dev = sev->dev;
2655 int ret;
2656
2657 /*
2658 * SEV feature support can be detected on multiple devices but the SEV
2659 * FW commands must be issued on the master. During probe, we do not
2660 * know the master hence we create /dev/sev on the first device probe.
2661 * sev_do_cmd() finds the right master device to which to issue the
2662 * command to the firmware.
2663 */
2664 if (!misc_dev) {
2665 struct miscdevice *misc;
2666
2667 misc_dev = kzalloc(sizeof(*misc_dev), GFP_KERNEL);
2668 if (!misc_dev)
2669 return -ENOMEM;
2670
2671 misc = &misc_dev->misc;
2672 misc->minor = MISC_DYNAMIC_MINOR;
2673 misc->name = DEVICE_NAME;
2674 misc->fops = &sev_fops;
2675
2676 ret = misc_register(misc);
2677 if (ret)
2678 return ret;
2679
2680 kref_init(&misc_dev->refcount);
2681 } else {
2682 kref_get(&misc_dev->refcount);
2683 }
2684
2685 init_waitqueue_head(&sev->int_queue);
2686 sev->misc = misc_dev;
2687 dev_dbg(dev, "registered SEV device\n");
2688
2689 return 0;
2690 }
2691
sev_dev_init(struct psp_device * psp)2692 int sev_dev_init(struct psp_device *psp)
2693 {
2694 struct device *dev = psp->dev;
2695 struct sev_device *sev;
2696 int ret = -ENOMEM;
2697
2698 if (!boot_cpu_has(X86_FEATURE_SEV)) {
2699 dev_info_once(dev, "SEV: memory encryption not enabled by BIOS\n");
2700 return 0;
2701 }
2702
2703 sev = devm_kzalloc(dev, sizeof(*sev), GFP_KERNEL);
2704 if (!sev)
2705 goto e_err;
2706
2707 sev->cmd_buf = (void *)devm_get_free_pages(dev, GFP_KERNEL, 1);
2708 if (!sev->cmd_buf)
2709 goto e_sev;
2710
2711 sev->cmd_buf_backup = (uint8_t *)sev->cmd_buf + PAGE_SIZE;
2712
2713 psp->sev_data = sev;
2714
2715 sev->dev = dev;
2716 sev->psp = psp;
2717
2718 sev->io_regs = psp->io_regs;
2719
2720 sev->vdata = (struct sev_vdata *)psp->vdata->sev;
2721 if (!sev->vdata) {
2722 ret = -ENODEV;
2723 dev_err(dev, "sev: missing driver data\n");
2724 goto e_buf;
2725 }
2726
2727 psp_set_sev_irq_handler(psp, sev_irq_handler, sev);
2728
2729 ret = sev_misc_init(sev);
2730 if (ret)
2731 goto e_irq;
2732
2733 dev_notice(dev, "sev enabled\n");
2734
2735 return 0;
2736
2737 e_irq:
2738 psp_clear_sev_irq_handler(psp);
2739 e_buf:
2740 devm_free_pages(dev, (unsigned long)sev->cmd_buf);
2741 e_sev:
2742 devm_kfree(dev, sev);
2743 e_err:
2744 psp->sev_data = NULL;
2745
2746 dev_notice(dev, "sev initialization failed\n");
2747
2748 return ret;
2749 }
2750
__sev_firmware_shutdown(struct sev_device * sev,bool panic)2751 static void __sev_firmware_shutdown(struct sev_device *sev, bool panic)
2752 {
2753 int error;
2754
2755 __sev_platform_shutdown_locked(&error);
2756
2757 if (sev_es_tmr) {
2758 /*
2759 * The TMR area was encrypted, flush it from the cache.
2760 *
2761 * If invoked during panic handling, local interrupts are
2762 * disabled and all CPUs are stopped, so wbinvd_on_all_cpus()
2763 * can't be used. In that case, wbinvd() is done on remote CPUs
2764 * via the NMI callback, and done for this CPU later during
2765 * SNP shutdown, so wbinvd_on_all_cpus() can be skipped.
2766 */
2767 if (!panic)
2768 wbinvd_on_all_cpus();
2769
2770 __snp_free_firmware_pages(virt_to_page(sev_es_tmr),
2771 get_order(sev_es_tmr_size),
2772 true);
2773 sev_es_tmr = NULL;
2774 }
2775
2776 if (sev_init_ex_buffer) {
2777 __snp_free_firmware_pages(virt_to_page(sev_init_ex_buffer),
2778 get_order(NV_LENGTH),
2779 true);
2780 sev_init_ex_buffer = NULL;
2781 }
2782
2783 if (snp_range_list) {
2784 kfree(snp_range_list);
2785 snp_range_list = NULL;
2786 }
2787
2788 __sev_snp_shutdown_locked(&error, panic);
2789 }
2790
sev_firmware_shutdown(struct sev_device * sev)2791 static void sev_firmware_shutdown(struct sev_device *sev)
2792 {
2793 /*
2794 * Calling without sev_cmd_mutex held as TSM will likely try disconnecting
2795 * IDE and this ends up calling sev_do_cmd() which locks sev_cmd_mutex.
2796 */
2797 if (sev->tio_status)
2798 sev_tsm_uninit(sev);
2799
2800 mutex_lock(&sev_cmd_mutex);
2801
2802 __sev_firmware_shutdown(sev, false);
2803
2804 kfree(sev->tio_status);
2805 sev->tio_status = NULL;
2806
2807 mutex_unlock(&sev_cmd_mutex);
2808 }
2809
sev_platform_shutdown(void)2810 void sev_platform_shutdown(void)
2811 {
2812 if (!psp_master || !psp_master->sev_data)
2813 return;
2814
2815 sev_firmware_shutdown(psp_master->sev_data);
2816 }
2817 EXPORT_SYMBOL_GPL(sev_platform_shutdown);
2818
sev_get_snp_policy_bits(void)2819 u64 sev_get_snp_policy_bits(void)
2820 {
2821 struct psp_device *psp = psp_master;
2822 struct sev_device *sev;
2823 u64 policy_bits;
2824
2825 if (!cc_platform_has(CC_ATTR_HOST_SEV_SNP))
2826 return 0;
2827
2828 if (!psp || !psp->sev_data)
2829 return 0;
2830
2831 sev = psp->sev_data;
2832
2833 policy_bits = SNP_POLICY_MASK_BASE;
2834
2835 if (sev->snp_plat_status.feature_info) {
2836 if (sev->snp_feat_info_0.ecx & SNP_RAPL_DISABLE_SUPPORTED)
2837 policy_bits |= SNP_POLICY_MASK_RAPL_DIS;
2838
2839 if (sev->snp_feat_info_0.ecx & SNP_CIPHER_TEXT_HIDING_SUPPORTED)
2840 policy_bits |= SNP_POLICY_MASK_CIPHERTEXT_HIDING_DRAM;
2841
2842 if (sev->snp_feat_info_0.ecx & SNP_AES_256_XTS_POLICY_SUPPORTED)
2843 policy_bits |= SNP_POLICY_MASK_MEM_AES_256_XTS;
2844
2845 if (sev->snp_feat_info_0.ecx & SNP_CXL_ALLOW_POLICY_SUPPORTED)
2846 policy_bits |= SNP_POLICY_MASK_CXL_ALLOW;
2847
2848 if (sev_version_greater_or_equal(1, 58))
2849 policy_bits |= SNP_POLICY_MASK_PAGE_SWAP_DISABLE;
2850 }
2851
2852 return policy_bits;
2853 }
2854 EXPORT_SYMBOL_GPL(sev_get_snp_policy_bits);
2855
sev_dev_destroy(struct psp_device * psp)2856 void sev_dev_destroy(struct psp_device *psp)
2857 {
2858 struct sev_device *sev = psp->sev_data;
2859
2860 if (!sev)
2861 return;
2862
2863 sev_firmware_shutdown(sev);
2864
2865 if (sev->misc)
2866 kref_put(&misc_dev->refcount, sev_exit);
2867
2868 psp_clear_sev_irq_handler(psp);
2869 }
2870
snp_shutdown_on_panic(struct notifier_block * nb,unsigned long reason,void * arg)2871 static int snp_shutdown_on_panic(struct notifier_block *nb,
2872 unsigned long reason, void *arg)
2873 {
2874 struct sev_device *sev = psp_master->sev_data;
2875
2876 /*
2877 * If sev_cmd_mutex is already acquired, then it's likely
2878 * another PSP command is in flight and issuing a shutdown
2879 * would fail in unexpected ways. Rather than create even
2880 * more confusion during a panic, just bail out here.
2881 */
2882 if (mutex_is_locked(&sev_cmd_mutex))
2883 return NOTIFY_DONE;
2884
2885 __sev_firmware_shutdown(sev, true);
2886
2887 return NOTIFY_DONE;
2888 }
2889
sev_issue_cmd_external_user(struct file * filep,unsigned int cmd,void * data,int * error)2890 int sev_issue_cmd_external_user(struct file *filep, unsigned int cmd,
2891 void *data, int *error)
2892 {
2893 if (!filep || filep->f_op != &sev_fops)
2894 return -EBADF;
2895
2896 return sev_do_cmd(cmd, data, error);
2897 }
2898 EXPORT_SYMBOL_GPL(sev_issue_cmd_external_user);
2899
sev_pci_init(void)2900 void sev_pci_init(void)
2901 {
2902 struct sev_device *sev = psp_master->sev_data;
2903 u8 api_major, api_minor, build;
2904
2905 if (!sev)
2906 return;
2907
2908 psp_timeout = psp_probe_timeout;
2909
2910 if (sev_get_api_version())
2911 goto err;
2912
2913 api_major = sev->api_major;
2914 api_minor = sev->api_minor;
2915 build = sev->build;
2916
2917 if (sev_update_firmware(sev->dev) == 0)
2918 sev_get_api_version();
2919
2920 if (api_major != sev->api_major || api_minor != sev->api_minor ||
2921 build != sev->build)
2922 dev_info(sev->dev, "SEV firmware updated from %d.%d.%d to %d.%d.%d\n",
2923 api_major, api_minor, build,
2924 sev->api_major, sev->api_minor, sev->build);
2925
2926 return;
2927
2928 err:
2929 sev_dev_destroy(psp_master);
2930
2931 psp_master->sev_data = NULL;
2932 }
2933
sev_pci_exit(void)2934 void sev_pci_exit(void)
2935 {
2936 struct sev_device *sev = psp_master->sev_data;
2937
2938 if (!sev)
2939 return;
2940
2941 sev_firmware_shutdown(sev);
2942 }
2943