xref: /linux/drivers/crypto/ccp/sev-dev.c (revision aec2f682d47c54ef434b2d440992626d80b1ebdc)
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 static void __sev_firmware_shutdown(struct sev_device *sev, bool panic);
131 
132 static int snp_shutdown_on_panic(struct notifier_block *nb,
133 				 unsigned long reason, void *arg);
134 
135 static struct notifier_block snp_panic_notifier = {
136 	.notifier_call = snp_shutdown_on_panic,
137 };
138 
sev_version_greater_or_equal(u8 maj,u8 min)139 static inline bool sev_version_greater_or_equal(u8 maj, u8 min)
140 {
141 	struct sev_device *sev = psp_master->sev_data;
142 
143 	if (sev->api_major > maj)
144 		return true;
145 
146 	if (sev->api_major == maj && sev->api_minor >= min)
147 		return true;
148 
149 	return false;
150 }
151 
sev_irq_handler(int irq,void * data,unsigned int status)152 static void sev_irq_handler(int irq, void *data, unsigned int status)
153 {
154 	struct sev_device *sev = data;
155 	int reg;
156 
157 	/* Check if it is command completion: */
158 	if (!(status & SEV_CMD_COMPLETE))
159 		return;
160 
161 	/* Check if it is SEV command completion: */
162 	reg = ioread32(sev->io_regs + sev->vdata->cmdresp_reg);
163 	if (FIELD_GET(PSP_CMDRESP_RESP, reg)) {
164 		sev->int_rcvd = 1;
165 		wake_up(&sev->int_queue);
166 	}
167 }
168 
sev_wait_cmd_ioc(struct sev_device * sev,unsigned int * reg,unsigned int timeout)169 static int sev_wait_cmd_ioc(struct sev_device *sev,
170 			    unsigned int *reg, unsigned int timeout)
171 {
172 	int ret;
173 
174 	/*
175 	 * If invoked during panic handling, local interrupts are disabled,
176 	 * so the PSP command completion interrupt can't be used. Poll for
177 	 * PSP command completion instead.
178 	 */
179 	if (irqs_disabled()) {
180 		unsigned long timeout_usecs = (timeout * USEC_PER_SEC) / 10;
181 
182 		/* Poll for SEV command completion: */
183 		while (timeout_usecs--) {
184 			*reg = ioread32(sev->io_regs + sev->vdata->cmdresp_reg);
185 			if (*reg & PSP_CMDRESP_RESP)
186 				return 0;
187 
188 			udelay(10);
189 		}
190 		return -ETIMEDOUT;
191 	}
192 
193 	ret = wait_event_timeout(sev->int_queue,
194 			sev->int_rcvd, timeout * HZ);
195 	if (!ret)
196 		return -ETIMEDOUT;
197 
198 	*reg = ioread32(sev->io_regs + sev->vdata->cmdresp_reg);
199 
200 	return 0;
201 }
202 
sev_cmd_buffer_len(int cmd)203 static int sev_cmd_buffer_len(int cmd)
204 {
205 	switch (cmd) {
206 	case SEV_CMD_INIT:			return sizeof(struct sev_data_init);
207 	case SEV_CMD_INIT_EX:                   return sizeof(struct sev_data_init_ex);
208 	case SEV_CMD_SNP_SHUTDOWN_EX:		return sizeof(struct sev_data_snp_shutdown_ex);
209 	case SEV_CMD_SNP_INIT_EX:		return sizeof(struct sev_data_snp_init_ex);
210 	case SEV_CMD_PLATFORM_STATUS:		return sizeof(struct sev_user_data_status);
211 	case SEV_CMD_PEK_CSR:			return sizeof(struct sev_data_pek_csr);
212 	case SEV_CMD_PEK_CERT_IMPORT:		return sizeof(struct sev_data_pek_cert_import);
213 	case SEV_CMD_PDH_CERT_EXPORT:		return sizeof(struct sev_data_pdh_cert_export);
214 	case SEV_CMD_LAUNCH_START:		return sizeof(struct sev_data_launch_start);
215 	case SEV_CMD_LAUNCH_UPDATE_DATA:	return sizeof(struct sev_data_launch_update_data);
216 	case SEV_CMD_LAUNCH_UPDATE_VMSA:	return sizeof(struct sev_data_launch_update_vmsa);
217 	case SEV_CMD_LAUNCH_FINISH:		return sizeof(struct sev_data_launch_finish);
218 	case SEV_CMD_LAUNCH_MEASURE:		return sizeof(struct sev_data_launch_measure);
219 	case SEV_CMD_ACTIVATE:			return sizeof(struct sev_data_activate);
220 	case SEV_CMD_DEACTIVATE:		return sizeof(struct sev_data_deactivate);
221 	case SEV_CMD_DECOMMISSION:		return sizeof(struct sev_data_decommission);
222 	case SEV_CMD_GUEST_STATUS:		return sizeof(struct sev_data_guest_status);
223 	case SEV_CMD_DBG_DECRYPT:		return sizeof(struct sev_data_dbg);
224 	case SEV_CMD_DBG_ENCRYPT:		return sizeof(struct sev_data_dbg);
225 	case SEV_CMD_SEND_START:		return sizeof(struct sev_data_send_start);
226 	case SEV_CMD_SEND_UPDATE_DATA:		return sizeof(struct sev_data_send_update_data);
227 	case SEV_CMD_SEND_UPDATE_VMSA:		return sizeof(struct sev_data_send_update_vmsa);
228 	case SEV_CMD_SEND_FINISH:		return sizeof(struct sev_data_send_finish);
229 	case SEV_CMD_RECEIVE_START:		return sizeof(struct sev_data_receive_start);
230 	case SEV_CMD_RECEIVE_FINISH:		return sizeof(struct sev_data_receive_finish);
231 	case SEV_CMD_RECEIVE_UPDATE_DATA:	return sizeof(struct sev_data_receive_update_data);
232 	case SEV_CMD_RECEIVE_UPDATE_VMSA:	return sizeof(struct sev_data_receive_update_vmsa);
233 	case SEV_CMD_LAUNCH_UPDATE_SECRET:	return sizeof(struct sev_data_launch_secret);
234 	case SEV_CMD_DOWNLOAD_FIRMWARE:		return sizeof(struct sev_data_download_firmware);
235 	case SEV_CMD_GET_ID:			return sizeof(struct sev_data_get_id);
236 	case SEV_CMD_ATTESTATION_REPORT:	return sizeof(struct sev_data_attestation_report);
237 	case SEV_CMD_SEND_CANCEL:		return sizeof(struct sev_data_send_cancel);
238 	case SEV_CMD_SNP_GCTX_CREATE:		return sizeof(struct sev_data_snp_addr);
239 	case SEV_CMD_SNP_LAUNCH_START:		return sizeof(struct sev_data_snp_launch_start);
240 	case SEV_CMD_SNP_LAUNCH_UPDATE:		return sizeof(struct sev_data_snp_launch_update);
241 	case SEV_CMD_SNP_ACTIVATE:		return sizeof(struct sev_data_snp_activate);
242 	case SEV_CMD_SNP_DECOMMISSION:		return sizeof(struct sev_data_snp_addr);
243 	case SEV_CMD_SNP_PAGE_RECLAIM:		return sizeof(struct sev_data_snp_page_reclaim);
244 	case SEV_CMD_SNP_GUEST_STATUS:		return sizeof(struct sev_data_snp_guest_status);
245 	case SEV_CMD_SNP_LAUNCH_FINISH:		return sizeof(struct sev_data_snp_launch_finish);
246 	case SEV_CMD_SNP_DBG_DECRYPT:		return sizeof(struct sev_data_snp_dbg);
247 	case SEV_CMD_SNP_DBG_ENCRYPT:		return sizeof(struct sev_data_snp_dbg);
248 	case SEV_CMD_SNP_PAGE_UNSMASH:		return sizeof(struct sev_data_snp_page_unsmash);
249 	case SEV_CMD_SNP_PLATFORM_STATUS:	return sizeof(struct sev_data_snp_addr);
250 	case SEV_CMD_SNP_GUEST_REQUEST:		return sizeof(struct sev_data_snp_guest_request);
251 	case SEV_CMD_SNP_CONFIG:		return sizeof(struct sev_user_data_snp_config);
252 	case SEV_CMD_SNP_COMMIT:		return sizeof(struct sev_data_snp_commit);
253 	case SEV_CMD_SNP_FEATURE_INFO:		return sizeof(struct sev_data_snp_feature_info);
254 	case SEV_CMD_SNP_VLEK_LOAD:		return sizeof(struct sev_user_data_snp_vlek_load);
255 	default:				return sev_tio_cmd_buffer_len(cmd);
256 	}
257 
258 	return 0;
259 }
260 
open_file_as_root(const char * filename,int flags,umode_t mode)261 static struct file *open_file_as_root(const char *filename, int flags, umode_t mode)
262 {
263 	struct path root __free(path_put) = {};
264 
265 	task_lock(&init_task);
266 	get_fs_root(init_task.fs, &root);
267 	task_unlock(&init_task);
268 
269 	CLASS(prepare_creds, cred)();
270 	if (!cred)
271 		return ERR_PTR(-ENOMEM);
272 
273 	cred->fsuid = GLOBAL_ROOT_UID;
274 
275 	scoped_with_creds(cred)
276 		return file_open_root(&root, filename, flags, mode);
277 }
278 
sev_read_init_ex_file(void)279 static int sev_read_init_ex_file(void)
280 {
281 	struct sev_device *sev = psp_master->sev_data;
282 	struct file *fp;
283 	ssize_t nread;
284 
285 	lockdep_assert_held(&sev_cmd_mutex);
286 
287 	if (!sev_init_ex_buffer)
288 		return -EOPNOTSUPP;
289 
290 	fp = open_file_as_root(init_ex_path, O_RDONLY, 0);
291 	if (IS_ERR(fp)) {
292 		int ret = PTR_ERR(fp);
293 
294 		if (ret == -ENOENT) {
295 			dev_info(sev->dev,
296 				"SEV: %s does not exist and will be created later.\n",
297 				init_ex_path);
298 			ret = 0;
299 		} else {
300 			dev_err(sev->dev,
301 				"SEV: could not open %s for read, error %d\n",
302 				init_ex_path, ret);
303 		}
304 		return ret;
305 	}
306 
307 	nread = kernel_read(fp, sev_init_ex_buffer, NV_LENGTH, NULL);
308 	if (nread != NV_LENGTH) {
309 		dev_info(sev->dev,
310 			"SEV: could not read %u bytes to non volatile memory area, ret %ld\n",
311 			NV_LENGTH, nread);
312 	}
313 
314 	dev_dbg(sev->dev, "SEV: read %ld bytes from NV file\n", nread);
315 	filp_close(fp, NULL);
316 
317 	return 0;
318 }
319 
sev_write_init_ex_file(void)320 static int sev_write_init_ex_file(void)
321 {
322 	struct sev_device *sev = psp_master->sev_data;
323 	struct file *fp;
324 	loff_t offset = 0;
325 	ssize_t nwrite;
326 
327 	lockdep_assert_held(&sev_cmd_mutex);
328 
329 	if (!sev_init_ex_buffer)
330 		return 0;
331 
332 	fp = open_file_as_root(init_ex_path, O_CREAT | O_WRONLY, 0600);
333 	if (IS_ERR(fp)) {
334 		int ret = PTR_ERR(fp);
335 
336 		dev_err(sev->dev,
337 			"SEV: could not open file for write, error %d\n",
338 			ret);
339 		return ret;
340 	}
341 
342 	nwrite = kernel_write(fp, sev_init_ex_buffer, NV_LENGTH, &offset);
343 	vfs_fsync(fp, 0);
344 	filp_close(fp, NULL);
345 
346 	if (nwrite != NV_LENGTH) {
347 		dev_err(sev->dev,
348 			"SEV: failed to write %u bytes to non volatile memory area, ret %ld\n",
349 			NV_LENGTH, nwrite);
350 		return -EIO;
351 	}
352 
353 	dev_dbg(sev->dev, "SEV: write successful to NV file\n");
354 
355 	return 0;
356 }
357 
sev_write_init_ex_file_if_required(int cmd_id)358 static int sev_write_init_ex_file_if_required(int cmd_id)
359 {
360 	lockdep_assert_held(&sev_cmd_mutex);
361 
362 	if (!sev_init_ex_buffer)
363 		return 0;
364 
365 	/*
366 	 * Only a few platform commands modify the SPI/NV area, but none of the
367 	 * non-platform commands do. Only INIT(_EX), PLATFORM_RESET, PEK_GEN,
368 	 * PEK_CERT_IMPORT, and PDH_GEN do.
369 	 */
370 	switch (cmd_id) {
371 	case SEV_CMD_FACTORY_RESET:
372 	case SEV_CMD_INIT_EX:
373 	case SEV_CMD_PDH_GEN:
374 	case SEV_CMD_PEK_CERT_IMPORT:
375 	case SEV_CMD_PEK_GEN:
376 		break;
377 	default:
378 		return 0;
379 	}
380 
381 	return sev_write_init_ex_file();
382 }
383 
snp_reclaim_pages(unsigned long paddr,unsigned int npages,bool locked)384 int snp_reclaim_pages(unsigned long paddr, unsigned int npages, bool locked)
385 {
386 	int ret, err, i;
387 
388 	paddr = __sme_clr(ALIGN_DOWN(paddr, PAGE_SIZE));
389 
390 	for (i = 0; i < npages; i++, paddr += PAGE_SIZE) {
391 		struct sev_data_snp_page_reclaim data = {0};
392 
393 		data.paddr = paddr;
394 
395 		if (locked)
396 			ret = __sev_do_cmd_locked(SEV_CMD_SNP_PAGE_RECLAIM, &data, &err);
397 		else
398 			ret = sev_do_cmd(SEV_CMD_SNP_PAGE_RECLAIM, &data, &err);
399 
400 		if (ret)
401 			goto cleanup;
402 
403 		ret = rmp_make_shared(__phys_to_pfn(paddr), PG_LEVEL_4K);
404 		if (ret)
405 			goto cleanup;
406 	}
407 
408 	return 0;
409 
410 cleanup:
411 	/*
412 	 * If there was a failure reclaiming the page then it is no longer safe
413 	 * to release it back to the system; leak it instead.
414 	 */
415 	snp_leak_pages(__phys_to_pfn(paddr), npages - i);
416 	return ret;
417 }
418 EXPORT_SYMBOL_GPL(snp_reclaim_pages);
419 
rmp_mark_pages_firmware(unsigned long paddr,unsigned int npages,bool locked)420 static int rmp_mark_pages_firmware(unsigned long paddr, unsigned int npages, bool locked)
421 {
422 	unsigned long pfn = __sme_clr(paddr) >> PAGE_SHIFT;
423 	int rc, i;
424 
425 	for (i = 0; i < npages; i++, pfn++) {
426 		rc = rmp_make_private(pfn, 0, PG_LEVEL_4K, 0, true);
427 		if (rc)
428 			goto cleanup;
429 	}
430 
431 	return 0;
432 
433 cleanup:
434 	/*
435 	 * Try unrolling the firmware state changes by
436 	 * reclaiming the pages which were already changed to the
437 	 * firmware state.
438 	 */
439 	snp_reclaim_pages(paddr, i, locked);
440 
441 	return rc;
442 }
443 
__snp_alloc_firmware_pages(gfp_t gfp_mask,int order,bool locked)444 static struct page *__snp_alloc_firmware_pages(gfp_t gfp_mask, int order, bool locked)
445 {
446 	unsigned long npages = 1ul << order, paddr;
447 	struct sev_device *sev;
448 	struct page *page;
449 
450 	if (!psp_master || !psp_master->sev_data)
451 		return NULL;
452 
453 	page = alloc_pages(gfp_mask, order);
454 	if (!page)
455 		return NULL;
456 
457 	/* If SEV-SNP is initialized then add the page in RMP table. */
458 	sev = psp_master->sev_data;
459 	if (!sev->snp_initialized)
460 		return page;
461 
462 	paddr = __pa((unsigned long)page_address(page));
463 	if (rmp_mark_pages_firmware(paddr, npages, locked))
464 		return NULL;
465 
466 	return page;
467 }
468 
snp_alloc_firmware_page(gfp_t gfp_mask)469 void *snp_alloc_firmware_page(gfp_t gfp_mask)
470 {
471 	struct page *page;
472 
473 	page = __snp_alloc_firmware_pages(gfp_mask, 0, false);
474 
475 	return page ? page_address(page) : NULL;
476 }
477 EXPORT_SYMBOL_GPL(snp_alloc_firmware_page);
478 
__snp_free_firmware_pages(struct page * page,int order,bool locked)479 static void __snp_free_firmware_pages(struct page *page, int order, bool locked)
480 {
481 	struct sev_device *sev = psp_master->sev_data;
482 	unsigned long paddr, npages = 1ul << order;
483 
484 	if (!page)
485 		return;
486 
487 	paddr = __pa((unsigned long)page_address(page));
488 	if (sev->snp_initialized &&
489 	    snp_reclaim_pages(paddr, npages, locked))
490 		return;
491 
492 	__free_pages(page, order);
493 }
494 
snp_free_firmware_page(void * addr)495 void snp_free_firmware_page(void *addr)
496 {
497 	if (!addr)
498 		return;
499 
500 	__snp_free_firmware_pages(virt_to_page(addr), 0, false);
501 }
502 EXPORT_SYMBOL_GPL(snp_free_firmware_page);
503 
sev_fw_alloc(unsigned long len)504 static void *sev_fw_alloc(unsigned long len)
505 {
506 	struct page *page;
507 
508 	page = __snp_alloc_firmware_pages(GFP_KERNEL, get_order(len), true);
509 	if (!page)
510 		return NULL;
511 
512 	return page_address(page);
513 }
514 
515 /**
516  * struct cmd_buf_desc - descriptors for managing legacy SEV command address
517  * parameters corresponding to buffers that may be written to by firmware.
518  *
519  * @paddr_ptr:  pointer to the address parameter in the command buffer which may
520  *              need to be saved/restored depending on whether a bounce buffer
521  *              is used. In the case of a bounce buffer, the command buffer
522  *              needs to be updated with the address of the new bounce buffer
523  *              snp_map_cmd_buf_desc() has allocated specifically for it. Must
524  *              be NULL if this descriptor is only an end-of-list indicator.
525  *
526  * @paddr_orig: storage for the original address parameter, which can be used to
527  *              restore the original value in @paddr_ptr in cases where it is
528  *              replaced with the address of a bounce buffer.
529  *
530  * @len: length of buffer located at the address originally stored at @paddr_ptr
531  *
532  * @guest_owned: true if the address corresponds to guest-owned pages, in which
533  *               case bounce buffers are not needed.
534  */
535 struct cmd_buf_desc {
536 	u64 *paddr_ptr;
537 	u64 paddr_orig;
538 	u32 len;
539 	bool guest_owned;
540 };
541 
542 /*
543  * If a legacy SEV command parameter is a memory address, those pages in
544  * turn need to be transitioned to/from firmware-owned before/after
545  * executing the firmware command.
546  *
547  * Additionally, in cases where those pages are not guest-owned, a bounce
548  * buffer is needed in place of the original memory address parameter.
549  *
550  * A set of descriptors are used to keep track of this handling, and
551  * initialized here based on the specific commands being executed.
552  */
snp_populate_cmd_buf_desc_list(int cmd,void * cmd_buf,struct cmd_buf_desc * desc_list)553 static void snp_populate_cmd_buf_desc_list(int cmd, void *cmd_buf,
554 					   struct cmd_buf_desc *desc_list)
555 {
556 	switch (cmd) {
557 	case SEV_CMD_PDH_CERT_EXPORT: {
558 		struct sev_data_pdh_cert_export *data = cmd_buf;
559 
560 		desc_list[0].paddr_ptr = &data->pdh_cert_address;
561 		desc_list[0].len = data->pdh_cert_len;
562 		desc_list[1].paddr_ptr = &data->cert_chain_address;
563 		desc_list[1].len = data->cert_chain_len;
564 		break;
565 	}
566 	case SEV_CMD_GET_ID: {
567 		struct sev_data_get_id *data = cmd_buf;
568 
569 		desc_list[0].paddr_ptr = &data->address;
570 		desc_list[0].len = data->len;
571 		break;
572 	}
573 	case SEV_CMD_PEK_CSR: {
574 		struct sev_data_pek_csr *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_LAUNCH_UPDATE_DATA: {
581 		struct sev_data_launch_update_data *data = cmd_buf;
582 
583 		desc_list[0].paddr_ptr = &data->address;
584 		desc_list[0].len = data->len;
585 		desc_list[0].guest_owned = true;
586 		break;
587 	}
588 	case SEV_CMD_LAUNCH_UPDATE_VMSA: {
589 		struct sev_data_launch_update_vmsa *data = cmd_buf;
590 
591 		desc_list[0].paddr_ptr = &data->address;
592 		desc_list[0].len = data->len;
593 		desc_list[0].guest_owned = true;
594 		break;
595 	}
596 	case SEV_CMD_LAUNCH_MEASURE: {
597 		struct sev_data_launch_measure *data = cmd_buf;
598 
599 		desc_list[0].paddr_ptr = &data->address;
600 		desc_list[0].len = data->len;
601 		break;
602 	}
603 	case SEV_CMD_LAUNCH_UPDATE_SECRET: {
604 		struct sev_data_launch_secret *data = cmd_buf;
605 
606 		desc_list[0].paddr_ptr = &data->guest_address;
607 		desc_list[0].len = data->guest_len;
608 		desc_list[0].guest_owned = true;
609 		break;
610 	}
611 	case SEV_CMD_DBG_DECRYPT: {
612 		struct sev_data_dbg *data = cmd_buf;
613 
614 		desc_list[0].paddr_ptr = &data->dst_addr;
615 		desc_list[0].len = data->len;
616 		desc_list[0].guest_owned = true;
617 		break;
618 	}
619 	case SEV_CMD_DBG_ENCRYPT: {
620 		struct sev_data_dbg *data = cmd_buf;
621 
622 		desc_list[0].paddr_ptr = &data->dst_addr;
623 		desc_list[0].len = data->len;
624 		desc_list[0].guest_owned = true;
625 		break;
626 	}
627 	case SEV_CMD_ATTESTATION_REPORT: {
628 		struct sev_data_attestation_report *data = cmd_buf;
629 
630 		desc_list[0].paddr_ptr = &data->address;
631 		desc_list[0].len = data->len;
632 		break;
633 	}
634 	case SEV_CMD_SEND_START: {
635 		struct sev_data_send_start *data = cmd_buf;
636 
637 		desc_list[0].paddr_ptr = &data->session_address;
638 		desc_list[0].len = data->session_len;
639 		break;
640 	}
641 	case SEV_CMD_SEND_UPDATE_DATA: {
642 		struct sev_data_send_update_data *data = cmd_buf;
643 
644 		desc_list[0].paddr_ptr = &data->hdr_address;
645 		desc_list[0].len = data->hdr_len;
646 		desc_list[1].paddr_ptr = &data->trans_address;
647 		desc_list[1].len = data->trans_len;
648 		break;
649 	}
650 	case SEV_CMD_SEND_UPDATE_VMSA: {
651 		struct sev_data_send_update_vmsa *data = cmd_buf;
652 
653 		desc_list[0].paddr_ptr = &data->hdr_address;
654 		desc_list[0].len = data->hdr_len;
655 		desc_list[1].paddr_ptr = &data->trans_address;
656 		desc_list[1].len = data->trans_len;
657 		break;
658 	}
659 	case SEV_CMD_RECEIVE_UPDATE_DATA: {
660 		struct sev_data_receive_update_data *data = cmd_buf;
661 
662 		desc_list[0].paddr_ptr = &data->guest_address;
663 		desc_list[0].len = data->guest_len;
664 		desc_list[0].guest_owned = true;
665 		break;
666 	}
667 	case SEV_CMD_RECEIVE_UPDATE_VMSA: {
668 		struct sev_data_receive_update_vmsa *data = cmd_buf;
669 
670 		desc_list[0].paddr_ptr = &data->guest_address;
671 		desc_list[0].len = data->guest_len;
672 		desc_list[0].guest_owned = true;
673 		break;
674 	}
675 	default:
676 		break;
677 	}
678 }
679 
snp_map_cmd_buf_desc(struct cmd_buf_desc * desc)680 static int snp_map_cmd_buf_desc(struct cmd_buf_desc *desc)
681 {
682 	unsigned int npages;
683 
684 	if (!desc->len)
685 		return 0;
686 
687 	/* Allocate a bounce buffer if this isn't a guest owned page. */
688 	if (!desc->guest_owned) {
689 		struct page *page;
690 
691 		page = alloc_pages(GFP_KERNEL_ACCOUNT, get_order(desc->len));
692 		if (!page) {
693 			pr_warn("Failed to allocate bounce buffer for SEV legacy command.\n");
694 			return -ENOMEM;
695 		}
696 
697 		desc->paddr_orig = *desc->paddr_ptr;
698 		*desc->paddr_ptr = __psp_pa(page_to_virt(page));
699 	}
700 
701 	npages = PAGE_ALIGN(desc->len) >> PAGE_SHIFT;
702 
703 	/* Transition the buffer to firmware-owned. */
704 	if (rmp_mark_pages_firmware(*desc->paddr_ptr, npages, true)) {
705 		pr_warn("Error moving pages to firmware-owned state for SEV legacy command.\n");
706 		return -EFAULT;
707 	}
708 
709 	return 0;
710 }
711 
snp_unmap_cmd_buf_desc(struct cmd_buf_desc * desc)712 static int snp_unmap_cmd_buf_desc(struct cmd_buf_desc *desc)
713 {
714 	unsigned int npages;
715 
716 	if (!desc->len)
717 		return 0;
718 
719 	npages = PAGE_ALIGN(desc->len) >> PAGE_SHIFT;
720 
721 	/* Transition the buffers back to hypervisor-owned. */
722 	if (snp_reclaim_pages(*desc->paddr_ptr, npages, true)) {
723 		pr_warn("Failed to reclaim firmware-owned pages while issuing SEV legacy command.\n");
724 		return -EFAULT;
725 	}
726 
727 	/* Copy data from bounce buffer and then free it. */
728 	if (!desc->guest_owned) {
729 		void *bounce_buf = __va(__sme_clr(*desc->paddr_ptr));
730 		void *dst_buf = __va(__sme_clr(desc->paddr_orig));
731 
732 		memcpy(dst_buf, bounce_buf, desc->len);
733 		__free_pages(virt_to_page(bounce_buf), get_order(desc->len));
734 
735 		/* Restore the original address in the command buffer. */
736 		*desc->paddr_ptr = desc->paddr_orig;
737 	}
738 
739 	return 0;
740 }
741 
snp_map_cmd_buf_desc_list(int cmd,void * cmd_buf,struct cmd_buf_desc * desc_list)742 static int snp_map_cmd_buf_desc_list(int cmd, void *cmd_buf, struct cmd_buf_desc *desc_list)
743 {
744 	int i;
745 
746 	snp_populate_cmd_buf_desc_list(cmd, cmd_buf, desc_list);
747 
748 	for (i = 0; i < CMD_BUF_DESC_MAX; i++) {
749 		struct cmd_buf_desc *desc = &desc_list[i];
750 
751 		if (!desc->paddr_ptr)
752 			break;
753 
754 		if (snp_map_cmd_buf_desc(desc))
755 			goto err_unmap;
756 	}
757 
758 	return 0;
759 
760 err_unmap:
761 	for (i--; i >= 0; i--)
762 		snp_unmap_cmd_buf_desc(&desc_list[i]);
763 
764 	return -EFAULT;
765 }
766 
snp_unmap_cmd_buf_desc_list(struct cmd_buf_desc * desc_list)767 static int snp_unmap_cmd_buf_desc_list(struct cmd_buf_desc *desc_list)
768 {
769 	int i, ret = 0;
770 
771 	for (i = 0; i < CMD_BUF_DESC_MAX; i++) {
772 		struct cmd_buf_desc *desc = &desc_list[i];
773 
774 		if (!desc->paddr_ptr)
775 			break;
776 
777 		if (snp_unmap_cmd_buf_desc(&desc_list[i]))
778 			ret = -EFAULT;
779 	}
780 
781 	return ret;
782 }
783 
sev_cmd_buf_writable(int cmd)784 static bool sev_cmd_buf_writable(int cmd)
785 {
786 	switch (cmd) {
787 	case SEV_CMD_PLATFORM_STATUS:
788 	case SEV_CMD_GUEST_STATUS:
789 	case SEV_CMD_LAUNCH_START:
790 	case SEV_CMD_RECEIVE_START:
791 	case SEV_CMD_LAUNCH_MEASURE:
792 	case SEV_CMD_SEND_START:
793 	case SEV_CMD_SEND_UPDATE_DATA:
794 	case SEV_CMD_SEND_UPDATE_VMSA:
795 	case SEV_CMD_PEK_CSR:
796 	case SEV_CMD_PDH_CERT_EXPORT:
797 	case SEV_CMD_GET_ID:
798 	case SEV_CMD_ATTESTATION_REPORT:
799 		return true;
800 	default:
801 		return false;
802 	}
803 }
804 
805 /* After SNP is INIT'ed, the behavior of legacy SEV commands is changed. */
snp_legacy_handling_needed(int cmd)806 static bool snp_legacy_handling_needed(int cmd)
807 {
808 	struct sev_device *sev = psp_master->sev_data;
809 
810 	return cmd < SEV_CMD_SNP_INIT && sev->snp_initialized;
811 }
812 
snp_prep_cmd_buf(int cmd,void * cmd_buf,struct cmd_buf_desc * desc_list)813 static int snp_prep_cmd_buf(int cmd, void *cmd_buf, struct cmd_buf_desc *desc_list)
814 {
815 	if (!snp_legacy_handling_needed(cmd))
816 		return 0;
817 
818 	if (snp_map_cmd_buf_desc_list(cmd, cmd_buf, desc_list))
819 		return -EFAULT;
820 
821 	/*
822 	 * Before command execution, the command buffer needs to be put into
823 	 * the firmware-owned state.
824 	 */
825 	if (sev_cmd_buf_writable(cmd)) {
826 		if (rmp_mark_pages_firmware(__pa(cmd_buf), 1, true))
827 			return -EFAULT;
828 	}
829 
830 	return 0;
831 }
832 
snp_reclaim_cmd_buf(int cmd,void * cmd_buf)833 static int snp_reclaim_cmd_buf(int cmd, void *cmd_buf)
834 {
835 	if (!snp_legacy_handling_needed(cmd))
836 		return 0;
837 
838 	/*
839 	 * After command completion, the command buffer needs to be put back
840 	 * into the hypervisor-owned state.
841 	 */
842 	if (sev_cmd_buf_writable(cmd))
843 		if (snp_reclaim_pages(__pa(cmd_buf), 1, true))
844 			return -EFAULT;
845 
846 	return 0;
847 }
848 
__sev_do_cmd_locked(int cmd,void * data,int * psp_ret)849 int __sev_do_cmd_locked(int cmd, void *data, int *psp_ret)
850 {
851 	struct cmd_buf_desc desc_list[CMD_BUF_DESC_MAX] = {0};
852 	struct psp_device *psp = psp_master;
853 	struct sev_device *sev;
854 	unsigned int cmdbuff_hi, cmdbuff_lo;
855 	unsigned int phys_lsb, phys_msb;
856 	unsigned int reg;
857 	void *cmd_buf;
858 	int buf_len;
859 	int ret = 0;
860 
861 	if (!psp || !psp->sev_data)
862 		return -ENODEV;
863 
864 	if (psp_dead)
865 		return -EBUSY;
866 
867 	sev = psp->sev_data;
868 
869 	buf_len = sev_cmd_buffer_len(cmd);
870 	if (WARN_ON_ONCE(!data != !buf_len))
871 		return -EINVAL;
872 
873 	/*
874 	 * Copy the incoming data to driver's scratch buffer as __pa() will not
875 	 * work for some memory, e.g. vmalloc'd addresses, and @data may not be
876 	 * physically contiguous.
877 	 */
878 	if (data) {
879 		/*
880 		 * Commands are generally issued one at a time and require the
881 		 * sev_cmd_mutex, but there could be recursive firmware requests
882 		 * due to SEV_CMD_SNP_PAGE_RECLAIM needing to be issued while
883 		 * preparing buffers for another command. This is the only known
884 		 * case of nesting in the current code, so exactly one
885 		 * additional command buffer is available for that purpose.
886 		 */
887 		if (!sev->cmd_buf_active) {
888 			cmd_buf = sev->cmd_buf;
889 			sev->cmd_buf_active = true;
890 		} else if (!sev->cmd_buf_backup_active) {
891 			cmd_buf = sev->cmd_buf_backup;
892 			sev->cmd_buf_backup_active = true;
893 		} else {
894 			dev_err(sev->dev,
895 				"SEV: too many firmware commands in progress, no command buffers available.\n");
896 			return -EBUSY;
897 		}
898 
899 		memcpy(cmd_buf, data, buf_len);
900 
901 		/*
902 		 * The behavior of the SEV-legacy commands is altered when the
903 		 * SNP firmware is in the INIT state.
904 		 */
905 		ret = snp_prep_cmd_buf(cmd, cmd_buf, desc_list);
906 		if (ret) {
907 			dev_err(sev->dev,
908 				"SEV: failed to prepare buffer for legacy command 0x%x. Error: %d\n",
909 				cmd, ret);
910 			return ret;
911 		}
912 	} else {
913 		cmd_buf = sev->cmd_buf;
914 	}
915 
916 	/* Get the physical address of the command buffer */
917 	phys_lsb = data ? lower_32_bits(__psp_pa(cmd_buf)) : 0;
918 	phys_msb = data ? upper_32_bits(__psp_pa(cmd_buf)) : 0;
919 
920 	dev_dbg(sev->dev, "sev command id %#x buffer 0x%08x%08x timeout %us\n",
921 		cmd, phys_msb, phys_lsb, psp_timeout);
922 
923 	print_hex_dump_debug("(in):  ", DUMP_PREFIX_OFFSET, 16, 2, data,
924 			     buf_len, false);
925 
926 	iowrite32(phys_lsb, sev->io_regs + sev->vdata->cmdbuff_addr_lo_reg);
927 	iowrite32(phys_msb, sev->io_regs + sev->vdata->cmdbuff_addr_hi_reg);
928 
929 	sev->int_rcvd = 0;
930 
931 	reg = FIELD_PREP(SEV_CMDRESP_CMD, cmd);
932 
933 	/*
934 	 * If invoked during panic handling, local interrupts are disabled so
935 	 * the PSP command completion interrupt can't be used.
936 	 * sev_wait_cmd_ioc() already checks for interrupts disabled and
937 	 * polls for PSP command completion.  Ensure we do not request an
938 	 * interrupt from the PSP if irqs disabled.
939 	 */
940 	if (!irqs_disabled())
941 		reg |= SEV_CMDRESP_IOC;
942 
943 	iowrite32(reg, sev->io_regs + sev->vdata->cmdresp_reg);
944 
945 	/* wait for command completion */
946 	ret = sev_wait_cmd_ioc(sev, &reg, psp_timeout);
947 	if (ret) {
948 		if (psp_ret)
949 			*psp_ret = 0;
950 
951 		dev_err(sev->dev, "sev command %#x timed out, disabling PSP\n", cmd);
952 		psp_dead = true;
953 
954 		return ret;
955 	}
956 
957 	psp_timeout = psp_cmd_timeout;
958 
959 	if (psp_ret)
960 		*psp_ret = FIELD_GET(PSP_CMDRESP_STS, reg);
961 
962 	if (FIELD_GET(PSP_CMDRESP_STS, reg)) {
963 		dev_dbg(sev->dev, "sev command %#x failed (%#010lx)\n",
964 			cmd, FIELD_GET(PSP_CMDRESP_STS, reg));
965 
966 		/*
967 		 * PSP firmware may report additional error information in the
968 		 * command buffer registers on error. Print contents of command
969 		 * buffer registers if they changed.
970 		 */
971 		cmdbuff_hi = ioread32(sev->io_regs + sev->vdata->cmdbuff_addr_hi_reg);
972 		cmdbuff_lo = ioread32(sev->io_regs + sev->vdata->cmdbuff_addr_lo_reg);
973 		if (cmdbuff_hi != phys_msb || cmdbuff_lo != phys_lsb) {
974 			dev_dbg(sev->dev, "Additional error information reported in cmdbuff:");
975 			dev_dbg(sev->dev, "  cmdbuff hi: %#010x\n", cmdbuff_hi);
976 			dev_dbg(sev->dev, "  cmdbuff lo: %#010x\n", cmdbuff_lo);
977 		}
978 		ret = -EIO;
979 	} else {
980 		ret = sev_write_init_ex_file_if_required(cmd);
981 	}
982 
983 	/*
984 	 * Copy potential output from the PSP back to data.  Do this even on
985 	 * failure in case the caller wants to glean something from the error.
986 	 */
987 	if (data) {
988 		int ret_reclaim;
989 		/*
990 		 * Restore the page state after the command completes.
991 		 */
992 		ret_reclaim = snp_reclaim_cmd_buf(cmd, cmd_buf);
993 		if (ret_reclaim) {
994 			dev_err(sev->dev,
995 				"SEV: failed to reclaim buffer for legacy command %#x. Error: %d\n",
996 				cmd, ret_reclaim);
997 			return ret_reclaim;
998 		}
999 
1000 		memcpy(data, cmd_buf, buf_len);
1001 
1002 		if (sev->cmd_buf_backup_active)
1003 			sev->cmd_buf_backup_active = false;
1004 		else
1005 			sev->cmd_buf_active = false;
1006 
1007 		if (snp_unmap_cmd_buf_desc_list(desc_list))
1008 			return -EFAULT;
1009 	}
1010 
1011 	print_hex_dump_debug("(out): ", DUMP_PREFIX_OFFSET, 16, 2, data,
1012 			     buf_len, false);
1013 
1014 	return ret;
1015 }
1016 
sev_do_cmd(int cmd,void * data,int * psp_ret)1017 int sev_do_cmd(int cmd, void *data, int *psp_ret)
1018 {
1019 	int rc;
1020 
1021 	mutex_lock(&sev_cmd_mutex);
1022 	rc = __sev_do_cmd_locked(cmd, data, psp_ret);
1023 	mutex_unlock(&sev_cmd_mutex);
1024 
1025 	return rc;
1026 }
1027 EXPORT_SYMBOL_GPL(sev_do_cmd);
1028 
__sev_init_locked(int * error)1029 static int __sev_init_locked(int *error)
1030 {
1031 	struct sev_data_init data;
1032 
1033 	memset(&data, 0, sizeof(data));
1034 	if (sev_es_tmr) {
1035 		/*
1036 		 * Do not include the encryption mask on the physical
1037 		 * address of the TMR (firmware should clear it anyway).
1038 		 */
1039 		data.tmr_address = __pa(sev_es_tmr);
1040 
1041 		data.flags |= SEV_INIT_FLAGS_SEV_ES;
1042 		data.tmr_len = sev_es_tmr_size;
1043 	}
1044 
1045 	return __sev_do_cmd_locked(SEV_CMD_INIT, &data, error);
1046 }
1047 
__sev_init_ex_locked(int * error)1048 static int __sev_init_ex_locked(int *error)
1049 {
1050 	struct sev_data_init_ex data;
1051 
1052 	memset(&data, 0, sizeof(data));
1053 	data.length = sizeof(data);
1054 	data.nv_address = __psp_pa(sev_init_ex_buffer);
1055 	data.nv_len = NV_LENGTH;
1056 
1057 	if (sev_es_tmr) {
1058 		/*
1059 		 * Do not include the encryption mask on the physical
1060 		 * address of the TMR (firmware should clear it anyway).
1061 		 */
1062 		data.tmr_address = __pa(sev_es_tmr);
1063 
1064 		data.flags |= SEV_INIT_FLAGS_SEV_ES;
1065 		data.tmr_len = sev_es_tmr_size;
1066 	}
1067 
1068 	return __sev_do_cmd_locked(SEV_CMD_INIT_EX, &data, error);
1069 }
1070 
__sev_do_init_locked(int * psp_ret)1071 static inline int __sev_do_init_locked(int *psp_ret)
1072 {
1073 	if (sev_init_ex_buffer)
1074 		return __sev_init_ex_locked(psp_ret);
1075 	else
1076 		return __sev_init_locked(psp_ret);
1077 }
1078 
1079 /* Hypervisor Fixed pages API interface */
snp_hv_fixed_pages_state_update(struct sev_device * sev,enum snp_hv_fixed_pages_state page_state)1080 static void snp_hv_fixed_pages_state_update(struct sev_device *sev,
1081 					    enum snp_hv_fixed_pages_state page_state)
1082 {
1083 	struct snp_hv_fixed_pages_entry *entry;
1084 
1085 	/* List is protected by sev_cmd_mutex */
1086 	lockdep_assert_held(&sev_cmd_mutex);
1087 
1088 	if (list_empty(&snp_hv_fixed_pages))
1089 		return;
1090 
1091 	list_for_each_entry(entry, &snp_hv_fixed_pages, list)
1092 		entry->page_state = page_state;
1093 }
1094 
1095 /*
1096  * Allocate HV_FIXED pages in 2MB aligned sizes to ensure the whole
1097  * 2MB pages are marked as HV_FIXED.
1098  */
snp_alloc_hv_fixed_pages(unsigned int num_2mb_pages)1099 struct page *snp_alloc_hv_fixed_pages(unsigned int num_2mb_pages)
1100 {
1101 	struct psp_device *psp_master = psp_get_master_device();
1102 	struct snp_hv_fixed_pages_entry *entry;
1103 	unsigned int order;
1104 	struct page *page;
1105 
1106 	if (!psp_master)
1107 		return NULL;
1108 
1109 	order = get_order(PMD_SIZE * num_2mb_pages);
1110 
1111 	/*
1112 	 * SNP_INIT_EX is protected by sev_cmd_mutex, therefore this list
1113 	 * also needs to be protected using the same mutex.
1114 	 */
1115 	guard(mutex)(&sev_cmd_mutex);
1116 
1117 	/*
1118 	 * This API uses SNP_INIT_EX to transition allocated pages to HV_Fixed
1119 	 * page state, fail if SNP is already initialized.
1120 	 */
1121 	if (psp_master->sev_data &&
1122 	    ((struct sev_device *)psp_master->sev_data)->snp_initialized)
1123 		return NULL;
1124 
1125 	/* Re-use freed pages that match the request */
1126 	list_for_each_entry(entry, &snp_hv_fixed_pages, list) {
1127 		/* Hypervisor fixed page allocator implements exact fit policy */
1128 		if (entry->order == order && entry->free) {
1129 			entry->free = false;
1130 			memset(page_address(entry->page), 0,
1131 			       (1 << entry->order) * PAGE_SIZE);
1132 			return entry->page;
1133 		}
1134 	}
1135 
1136 	page = alloc_pages(GFP_KERNEL | __GFP_ZERO, order);
1137 	if (!page)
1138 		return NULL;
1139 
1140 	entry = kzalloc_obj(*entry);
1141 	if (!entry) {
1142 		__free_pages(page, order);
1143 		return NULL;
1144 	}
1145 
1146 	entry->page = page;
1147 	entry->order = order;
1148 	list_add_tail(&entry->list, &snp_hv_fixed_pages);
1149 
1150 	return page;
1151 }
1152 
snp_free_hv_fixed_pages(struct page * page)1153 void snp_free_hv_fixed_pages(struct page *page)
1154 {
1155 	struct psp_device *psp_master = psp_get_master_device();
1156 	struct snp_hv_fixed_pages_entry *entry, *nentry;
1157 
1158 	if (!psp_master)
1159 		return;
1160 
1161 	/*
1162 	 * SNP_INIT_EX is protected by sev_cmd_mutex, therefore this list
1163 	 * also needs to be protected using the same mutex.
1164 	 */
1165 	guard(mutex)(&sev_cmd_mutex);
1166 
1167 	list_for_each_entry_safe(entry, nentry, &snp_hv_fixed_pages, list) {
1168 		if (entry->page != page)
1169 			continue;
1170 
1171 		/*
1172 		 * HV_FIXED page state cannot be changed until reboot
1173 		 * and they cannot be used by an SNP guest, so they cannot
1174 		 * be returned back to the page allocator.
1175 		 * Mark the pages as free internally to allow possible re-use.
1176 		 */
1177 		if (entry->page_state == HV_FIXED) {
1178 			entry->free = true;
1179 		} else {
1180 			__free_pages(page, entry->order);
1181 			list_del(&entry->list);
1182 			kfree(entry);
1183 		}
1184 		return;
1185 	}
1186 }
1187 
snp_add_hv_fixed_pages(struct sev_device * sev,struct sev_data_range_list * range_list)1188 static void snp_add_hv_fixed_pages(struct sev_device *sev, struct sev_data_range_list *range_list)
1189 {
1190 	struct snp_hv_fixed_pages_entry *entry;
1191 	struct sev_data_range *range;
1192 	int num_elements;
1193 
1194 	lockdep_assert_held(&sev_cmd_mutex);
1195 
1196 	if (list_empty(&snp_hv_fixed_pages))
1197 		return;
1198 
1199 	num_elements = list_count_nodes(&snp_hv_fixed_pages) +
1200 		       range_list->num_elements;
1201 
1202 	/*
1203 	 * Ensure the list of HV_FIXED pages that will be passed to firmware
1204 	 * do not exceed the page-sized argument buffer.
1205 	 */
1206 	if (num_elements * sizeof(*range) + sizeof(*range_list) > PAGE_SIZE) {
1207 		dev_warn(sev->dev, "Additional HV_Fixed pages cannot be accommodated, omitting\n");
1208 		return;
1209 	}
1210 
1211 	range = &range_list->ranges[range_list->num_elements];
1212 	list_for_each_entry(entry, &snp_hv_fixed_pages, list) {
1213 		range->base = page_to_pfn(entry->page) << PAGE_SHIFT;
1214 		range->page_count = 1 << entry->order;
1215 		range++;
1216 	}
1217 	range_list->num_elements = num_elements;
1218 }
1219 
snp_leak_hv_fixed_pages(void)1220 static void snp_leak_hv_fixed_pages(void)
1221 {
1222 	struct snp_hv_fixed_pages_entry *entry, *nentry;
1223 
1224 	/* List is protected by sev_cmd_mutex */
1225 	lockdep_assert_held(&sev_cmd_mutex);
1226 
1227 	if (list_empty(&snp_hv_fixed_pages))
1228 		return;
1229 
1230 	list_for_each_entry_safe(entry, nentry, &snp_hv_fixed_pages, list) {
1231 		if (entry->free && entry->page_state != HV_FIXED)
1232 			__free_pages(entry->page, entry->order);
1233 		else
1234 			__snp_leak_pages(page_to_pfn(entry->page),
1235 					 1 << entry->order, false);
1236 
1237 		list_del(&entry->list);
1238 		kfree(entry);
1239 	}
1240 }
1241 
sev_is_snp_ciphertext_hiding_supported(void)1242 bool sev_is_snp_ciphertext_hiding_supported(void)
1243 {
1244 	struct psp_device *psp = psp_master;
1245 	struct sev_device *sev;
1246 
1247 	if (!psp || !psp->sev_data)
1248 		return false;
1249 
1250 	sev = psp->sev_data;
1251 
1252 	/*
1253 	 * Feature information indicates if CipherTextHiding feature is
1254 	 * supported by the SEV firmware and additionally platform status
1255 	 * indicates if CipherTextHiding feature is enabled in the
1256 	 * Platform BIOS.
1257 	 */
1258 	return ((sev->snp_feat_info_0.ecx & SNP_CIPHER_TEXT_HIDING_SUPPORTED) &&
1259 		 sev->snp_plat_status.ciphertext_hiding_cap);
1260 }
1261 EXPORT_SYMBOL_GPL(sev_is_snp_ciphertext_hiding_supported);
1262 
snp_get_platform_data(struct sev_device * sev,int * error)1263 static int snp_get_platform_data(struct sev_device *sev, int *error)
1264 {
1265 	struct sev_data_snp_feature_info snp_feat_info;
1266 	struct snp_feature_info *feat_info;
1267 	struct sev_data_snp_addr buf;
1268 	struct page *page;
1269 	int rc;
1270 
1271 	/*
1272 	 * This function is expected to be called before SNP is
1273 	 * initialized.
1274 	 */
1275 	if (sev->snp_initialized)
1276 		return -EINVAL;
1277 
1278 	buf.address = __psp_pa(&sev->snp_plat_status);
1279 	rc = sev_do_cmd(SEV_CMD_SNP_PLATFORM_STATUS, &buf, error);
1280 	if (rc) {
1281 		dev_err(sev->dev, "SNP PLATFORM_STATUS command failed, ret = %d, error = %#x\n",
1282 			rc, *error);
1283 		return rc;
1284 	}
1285 
1286 	sev->api_major = sev->snp_plat_status.api_major;
1287 	sev->api_minor = sev->snp_plat_status.api_minor;
1288 	sev->build = sev->snp_plat_status.build_id;
1289 
1290 	/*
1291 	 * Do feature discovery of the currently loaded firmware,
1292 	 * and cache feature information from CPUID 0x8000_0024,
1293 	 * sub-function 0.
1294 	 */
1295 	if (!sev->snp_plat_status.feature_info)
1296 		return 0;
1297 
1298 	/*
1299 	 * Use dynamically allocated structure for the SNP_FEATURE_INFO
1300 	 * command to ensure structure is 8-byte aligned, and does not
1301 	 * cross a page boundary.
1302 	 */
1303 	page = alloc_page(GFP_KERNEL);
1304 	if (!page)
1305 		return -ENOMEM;
1306 
1307 	feat_info = page_address(page);
1308 	snp_feat_info.length = sizeof(snp_feat_info);
1309 	snp_feat_info.ecx_in = 0;
1310 	snp_feat_info.feature_info_paddr = __psp_pa(feat_info);
1311 
1312 	rc = sev_do_cmd(SEV_CMD_SNP_FEATURE_INFO, &snp_feat_info, error);
1313 	if (!rc)
1314 		sev->snp_feat_info_0 = *feat_info;
1315 	else
1316 		dev_err(sev->dev, "SNP FEATURE_INFO command failed, ret = %d, error = %#x\n",
1317 			rc, *error);
1318 
1319 	__free_page(page);
1320 
1321 	return rc;
1322 }
1323 
snp_filter_reserved_mem_regions(struct resource * rs,void * arg)1324 static int snp_filter_reserved_mem_regions(struct resource *rs, void *arg)
1325 {
1326 	struct sev_data_range_list *range_list = arg;
1327 	struct sev_data_range *range = &range_list->ranges[range_list->num_elements];
1328 	size_t size;
1329 
1330 	/*
1331 	 * Ensure the list of HV_FIXED pages that will be passed to firmware
1332 	 * do not exceed the page-sized argument buffer.
1333 	 */
1334 	if ((range_list->num_elements * sizeof(struct sev_data_range) +
1335 	     sizeof(struct sev_data_range_list)) > PAGE_SIZE)
1336 		return -E2BIG;
1337 
1338 	switch (rs->desc) {
1339 	case E820_TYPE_RESERVED:
1340 	case E820_TYPE_PMEM:
1341 	case E820_TYPE_ACPI:
1342 		range->base = rs->start & PAGE_MASK;
1343 		size = PAGE_ALIGN((rs->end + 1) - rs->start);
1344 		range->page_count = size >> PAGE_SHIFT;
1345 		range_list->num_elements++;
1346 		break;
1347 	default:
1348 		break;
1349 	}
1350 
1351 	return 0;
1352 }
1353 
__sev_snp_init_locked(int * error,unsigned int max_snp_asid)1354 static int __sev_snp_init_locked(int *error, unsigned int max_snp_asid)
1355 {
1356 	struct sev_data_range_list *snp_range_list __free(kfree) = NULL;
1357 	struct psp_device *psp = psp_master;
1358 	struct sev_data_snp_init_ex data;
1359 	struct sev_device *sev;
1360 	void *arg = &data;
1361 	int cmd, rc = 0;
1362 
1363 	if (!cc_platform_has(CC_ATTR_HOST_SEV_SNP))
1364 		return -ENODEV;
1365 
1366 	sev = psp->sev_data;
1367 
1368 	if (sev->snp_initialized)
1369 		return 0;
1370 
1371 	if (!sev_version_greater_or_equal(SNP_MIN_API_MAJOR, SNP_MIN_API_MINOR)) {
1372 		dev_dbg(sev->dev, "SEV-SNP support requires firmware version >= %d:%d\n",
1373 			SNP_MIN_API_MAJOR, SNP_MIN_API_MINOR);
1374 		return -EOPNOTSUPP;
1375 	}
1376 
1377 	snp_prepare();
1378 
1379 	/*
1380 	 * Starting in SNP firmware v1.52, the SNP_INIT_EX command takes a list
1381 	 * of system physical address ranges to convert into HV-fixed page
1382 	 * states during the RMP initialization.  For instance, the memory that
1383 	 * UEFI reserves should be included in the that list. This allows system
1384 	 * components that occasionally write to memory (e.g. logging to UEFI
1385 	 * reserved regions) to not fail due to RMP initialization and SNP
1386 	 * enablement.
1387 	 *
1388 	 */
1389 	if (sev_version_greater_or_equal(SNP_MIN_API_MAJOR, 52)) {
1390 		bool tio_supp = !!(sev->snp_feat_info_0.ebx & SNP_SEV_TIO_SUPPORTED);
1391 
1392 		/*
1393 		 * Firmware checks that the pages containing the ranges enumerated
1394 		 * in the RANGES structure are either in the default page state or in the
1395 		 * firmware page state.
1396 		 */
1397 		snp_range_list = kzalloc(PAGE_SIZE, GFP_KERNEL);
1398 		if (!snp_range_list) {
1399 			dev_err(sev->dev,
1400 				"SEV: SNP_INIT_EX range list memory allocation failed\n");
1401 			return -ENOMEM;
1402 		}
1403 
1404 		/*
1405 		 * Retrieve all reserved memory regions from the e820 memory map
1406 		 * to be setup as HV-fixed pages.
1407 		 */
1408 		rc = walk_iomem_res_desc(IORES_DESC_NONE, IORESOURCE_MEM, 0, ~0,
1409 					 snp_range_list, snp_filter_reserved_mem_regions);
1410 		if (rc) {
1411 			dev_err(sev->dev,
1412 				"SEV: SNP_INIT_EX walk_iomem_res_desc failed rc = %d\n", rc);
1413 			return rc;
1414 		}
1415 
1416 		/*
1417 		 * Add HV_Fixed pages from other PSP sub-devices, such as SFS to the
1418 		 * HV_Fixed page list.
1419 		 */
1420 		snp_add_hv_fixed_pages(sev, snp_range_list);
1421 
1422 		memset(&data, 0, sizeof(data));
1423 
1424 		if (max_snp_asid) {
1425 			data.ciphertext_hiding_en = 1;
1426 			data.max_snp_asid = max_snp_asid;
1427 		}
1428 
1429 		data.init_rmp = 1;
1430 		data.list_paddr_en = 1;
1431 		data.list_paddr = __psp_pa(snp_range_list);
1432 
1433 		data.tio_en = tio_supp && sev_tio_enabled && amd_iommu_sev_tio_supported();
1434 
1435 		/*
1436 		 * When psp_init_on_probe is disabled, the userspace calling
1437 		 * SEV ioctl can inadvertently shut down SNP and SEV-TIO causing
1438 		 * unexpected state loss.
1439 		 */
1440 		if (data.tio_en && !psp_init_on_probe)
1441 			dev_warn(sev->dev, "SEV-TIO as incompatible with psp_init_on_probe=0\n");
1442 
1443 		cmd = SEV_CMD_SNP_INIT_EX;
1444 	} else {
1445 		cmd = SEV_CMD_SNP_INIT;
1446 		arg = NULL;
1447 	}
1448 
1449 	/*
1450 	 * The following sequence must be issued before launching the first SNP
1451 	 * guest to ensure all dirty cache lines are flushed, including from
1452 	 * updates to the RMP table itself via the RMPUPDATE instruction:
1453 	 *
1454 	 * - WBINVD on all running CPUs
1455 	 * - SEV_CMD_SNP_INIT[_EX] firmware command
1456 	 * - WBINVD on all running CPUs
1457 	 * - SEV_CMD_SNP_DF_FLUSH firmware command
1458 	 */
1459 	wbinvd_on_all_cpus();
1460 
1461 	rc = __sev_do_cmd_locked(cmd, arg, error);
1462 	if (rc) {
1463 		dev_err(sev->dev, "SEV-SNP: %s failed rc %d, error %#x\n",
1464 			cmd == SEV_CMD_SNP_INIT_EX ? "SNP_INIT_EX" : "SNP_INIT",
1465 			rc, *error);
1466 		return rc;
1467 	}
1468 
1469 	/* Prepare for first SNP guest launch after INIT. */
1470 	wbinvd_on_all_cpus();
1471 	rc = __sev_do_cmd_locked(SEV_CMD_SNP_DF_FLUSH, NULL, error);
1472 	if (rc) {
1473 		dev_err(sev->dev, "SEV-SNP: SNP_DF_FLUSH failed rc %d, error %#x\n",
1474 			rc, *error);
1475 		return rc;
1476 	}
1477 
1478 	snp_hv_fixed_pages_state_update(sev, HV_FIXED);
1479 	sev->snp_initialized = true;
1480 	dev_dbg(sev->dev, "SEV-SNP firmware initialized, SEV-TIO is %s\n",
1481 		data.tio_en ? "enabled" : "disabled");
1482 
1483 	dev_info(sev->dev, "SEV-SNP API:%d.%d build:%d\n", sev->api_major,
1484 		 sev->api_minor, sev->build);
1485 
1486 	atomic_notifier_chain_register(&panic_notifier_list,
1487 				       &snp_panic_notifier);
1488 
1489 	if (data.tio_en) {
1490 		/*
1491 		 * This executes with the sev_cmd_mutex held so down the stack
1492 		 * snp_reclaim_pages(locked=false) might be needed (which is extremely
1493 		 * unlikely) but will cause a deadlock.
1494 		 * Instead of exporting __snp_alloc_firmware_pages(), allocate a page
1495 		 * for this one call here.
1496 		 */
1497 		void *tio_status = page_address(__snp_alloc_firmware_pages(
1498 			GFP_KERNEL_ACCOUNT | __GFP_ZERO, 0, true));
1499 
1500 		if (tio_status) {
1501 			sev_tsm_init_locked(sev, tio_status);
1502 			__snp_free_firmware_pages(virt_to_page(tio_status), 0, true);
1503 		}
1504 	}
1505 
1506 	sev_es_tmr_size = SNP_TMR_SIZE;
1507 
1508 	return 0;
1509 }
1510 
__sev_platform_init_handle_tmr(struct sev_device * sev)1511 static void __sev_platform_init_handle_tmr(struct sev_device *sev)
1512 {
1513 	if (sev_es_tmr)
1514 		return;
1515 
1516 	/* Obtain the TMR memory area for SEV-ES use */
1517 	sev_es_tmr = sev_fw_alloc(sev_es_tmr_size);
1518 	if (sev_es_tmr) {
1519 		/* Must flush the cache before giving it to the firmware */
1520 		if (!sev->snp_initialized)
1521 			clflush_cache_range(sev_es_tmr, sev_es_tmr_size);
1522 	} else {
1523 			dev_warn(sev->dev, "SEV: TMR allocation failed, SEV-ES support unavailable\n");
1524 	}
1525 }
1526 
1527 /*
1528  * If an init_ex_path is provided allocate a buffer for the file and
1529  * read in the contents. Additionally, if SNP is initialized, convert
1530  * the buffer pages to firmware pages.
1531  */
__sev_platform_init_handle_init_ex_path(struct sev_device * sev)1532 static int __sev_platform_init_handle_init_ex_path(struct sev_device *sev)
1533 {
1534 	struct page *page;
1535 	int rc;
1536 
1537 	if (!init_ex_path)
1538 		return 0;
1539 
1540 	if (sev_init_ex_buffer)
1541 		return 0;
1542 
1543 	page = alloc_pages(GFP_KERNEL, get_order(NV_LENGTH));
1544 	if (!page) {
1545 		dev_err(sev->dev, "SEV: INIT_EX NV memory allocation failed\n");
1546 		return -ENOMEM;
1547 	}
1548 
1549 	sev_init_ex_buffer = page_address(page);
1550 
1551 	rc = sev_read_init_ex_file();
1552 	if (rc)
1553 		return rc;
1554 
1555 	/* If SEV-SNP is initialized, transition to firmware page. */
1556 	if (sev->snp_initialized) {
1557 		unsigned long npages;
1558 
1559 		npages = 1UL << get_order(NV_LENGTH);
1560 		if (rmp_mark_pages_firmware(__pa(sev_init_ex_buffer), npages, false)) {
1561 			dev_err(sev->dev, "SEV: INIT_EX NV memory page state change failed.\n");
1562 			return -ENOMEM;
1563 		}
1564 	}
1565 
1566 	return 0;
1567 }
1568 
__sev_platform_init_locked(int * error)1569 static int __sev_platform_init_locked(int *error)
1570 {
1571 	int rc, psp_ret, dfflush_error;
1572 	struct sev_device *sev;
1573 
1574 	psp_ret = dfflush_error = SEV_RET_NO_FW_CALL;
1575 
1576 	if (!psp_master || !psp_master->sev_data)
1577 		return -ENODEV;
1578 
1579 	sev = psp_master->sev_data;
1580 
1581 	if (sev->sev_plat_status.state == SEV_STATE_INIT)
1582 		return 0;
1583 
1584 	__sev_platform_init_handle_tmr(sev);
1585 
1586 	rc = __sev_platform_init_handle_init_ex_path(sev);
1587 	if (rc)
1588 		return rc;
1589 
1590 	rc = __sev_do_init_locked(&psp_ret);
1591 	if (rc && psp_ret == SEV_RET_SECURE_DATA_INVALID) {
1592 		/*
1593 		 * Initialization command returned an integrity check failure
1594 		 * status code, meaning that firmware load and validation of SEV
1595 		 * related persistent data has failed. Retrying the
1596 		 * initialization function should succeed by replacing the state
1597 		 * with a reset state.
1598 		 */
1599 		dev_err(sev->dev,
1600 "SEV: retrying INIT command because of SECURE_DATA_INVALID error. Retrying once to reset PSP SEV state.");
1601 		rc = __sev_do_init_locked(&psp_ret);
1602 	}
1603 
1604 	if (error)
1605 		*error = psp_ret;
1606 
1607 	if (rc) {
1608 		dev_err(sev->dev, "SEV: %s failed %#x, rc %d\n",
1609 			sev_init_ex_buffer ? "INIT_EX" : "INIT", psp_ret, rc);
1610 		return rc;
1611 	}
1612 
1613 	sev->sev_plat_status.state = SEV_STATE_INIT;
1614 
1615 	/* Prepare for first SEV guest launch after INIT */
1616 	wbinvd_on_all_cpus();
1617 	rc = __sev_do_cmd_locked(SEV_CMD_DF_FLUSH, NULL, &dfflush_error);
1618 	if (rc) {
1619 		dev_err(sev->dev, "SEV: DF_FLUSH failed %#x, rc %d\n",
1620 			dfflush_error, rc);
1621 		return rc;
1622 	}
1623 
1624 	dev_dbg(sev->dev, "SEV firmware initialized\n");
1625 
1626 	dev_info(sev->dev, "SEV API:%d.%d build:%d\n", sev->api_major,
1627 		 sev->api_minor, sev->build);
1628 
1629 	return 0;
1630 }
1631 
_sev_platform_init_locked(struct sev_platform_init_args * args)1632 static int _sev_platform_init_locked(struct sev_platform_init_args *args)
1633 {
1634 	struct sev_device *sev;
1635 	int rc;
1636 
1637 	if (!psp_master || !psp_master->sev_data)
1638 		return -ENODEV;
1639 
1640 	/*
1641 	 * Skip SNP/SEV initialization under a kdump kernel as SEV/SNP
1642 	 * may already be initialized in the previous kernel. Since no
1643 	 * SNP/SEV guests are run under a kdump kernel, there is no
1644 	 * need to initialize SNP or SEV during kdump boot.
1645 	 */
1646 	if (is_kdump_kernel())
1647 		return 0;
1648 
1649 	sev = psp_master->sev_data;
1650 
1651 	if (sev->sev_plat_status.state == SEV_STATE_INIT)
1652 		return 0;
1653 
1654 	rc = __sev_snp_init_locked(&args->error, args->max_snp_asid);
1655 	if (rc && rc != -ENODEV)
1656 		return rc;
1657 
1658 	/* Defer legacy SEV/SEV-ES support if allowed by caller/module. */
1659 	if (args->probe && !psp_init_on_probe)
1660 		return 0;
1661 
1662 	return __sev_platform_init_locked(&args->error);
1663 }
1664 
sev_platform_init(struct sev_platform_init_args * args)1665 int sev_platform_init(struct sev_platform_init_args *args)
1666 {
1667 	int rc;
1668 
1669 	mutex_lock(&sev_cmd_mutex);
1670 	rc = _sev_platform_init_locked(args);
1671 	mutex_unlock(&sev_cmd_mutex);
1672 
1673 	return rc;
1674 }
1675 EXPORT_SYMBOL_GPL(sev_platform_init);
1676 
__sev_platform_shutdown_locked(int * error)1677 static int __sev_platform_shutdown_locked(int *error)
1678 {
1679 	struct psp_device *psp = psp_master;
1680 	struct sev_device *sev;
1681 	int ret;
1682 
1683 	if (!psp || !psp->sev_data)
1684 		return 0;
1685 
1686 	sev = psp->sev_data;
1687 
1688 	if (sev->sev_plat_status.state == SEV_STATE_UNINIT)
1689 		return 0;
1690 
1691 	ret = __sev_do_cmd_locked(SEV_CMD_SHUTDOWN, NULL, error);
1692 	if (ret) {
1693 		dev_err(sev->dev, "SEV: failed to SHUTDOWN error %#x, rc %d\n",
1694 			*error, ret);
1695 		return ret;
1696 	}
1697 
1698 	sev->sev_plat_status.state = SEV_STATE_UNINIT;
1699 	dev_dbg(sev->dev, "SEV firmware shutdown\n");
1700 
1701 	return ret;
1702 }
1703 
sev_get_platform_state(int * state,int * error)1704 static int sev_get_platform_state(int *state, int *error)
1705 {
1706 	struct sev_user_data_status data;
1707 	int rc;
1708 
1709 	rc = __sev_do_cmd_locked(SEV_CMD_PLATFORM_STATUS, &data, error);
1710 	if (rc)
1711 		return rc;
1712 
1713 	*state = data.state;
1714 	return rc;
1715 }
1716 
sev_move_to_init_state(struct sev_issue_cmd * argp,bool * shutdown_required)1717 static int sev_move_to_init_state(struct sev_issue_cmd *argp, bool *shutdown_required)
1718 {
1719 	struct sev_platform_init_args init_args = {0};
1720 	int rc;
1721 
1722 	rc = _sev_platform_init_locked(&init_args);
1723 	if (rc) {
1724 		argp->error = SEV_RET_INVALID_PLATFORM_STATE;
1725 		return rc;
1726 	}
1727 
1728 	*shutdown_required = true;
1729 
1730 	return 0;
1731 }
1732 
snp_move_to_init_state(struct sev_issue_cmd * argp,bool * shutdown_required)1733 static int snp_move_to_init_state(struct sev_issue_cmd *argp, bool *shutdown_required)
1734 {
1735 	int error, rc;
1736 
1737 	rc = __sev_snp_init_locked(&error, 0);
1738 	if (rc) {
1739 		argp->error = SEV_RET_INVALID_PLATFORM_STATE;
1740 		return rc;
1741 	}
1742 
1743 	*shutdown_required = true;
1744 
1745 	return 0;
1746 }
1747 
sev_ioctl_do_reset(struct sev_issue_cmd * argp,bool writable)1748 static int sev_ioctl_do_reset(struct sev_issue_cmd *argp, bool writable)
1749 {
1750 	int state, rc;
1751 
1752 	if (!writable)
1753 		return -EPERM;
1754 
1755 	/*
1756 	 * The SEV spec requires that FACTORY_RESET must be issued in
1757 	 * UNINIT state. Before we go further lets check if any guest is
1758 	 * active.
1759 	 *
1760 	 * If FW is in WORKING state then deny the request otherwise issue
1761 	 * SHUTDOWN command do INIT -> UNINIT before issuing the FACTORY_RESET.
1762 	 *
1763 	 */
1764 	rc = sev_get_platform_state(&state, &argp->error);
1765 	if (rc)
1766 		return rc;
1767 
1768 	if (state == SEV_STATE_WORKING)
1769 		return -EBUSY;
1770 
1771 	if (state == SEV_STATE_INIT) {
1772 		rc = __sev_platform_shutdown_locked(&argp->error);
1773 		if (rc)
1774 			return rc;
1775 	}
1776 
1777 	return __sev_do_cmd_locked(SEV_CMD_FACTORY_RESET, NULL, &argp->error);
1778 }
1779 
sev_ioctl_do_platform_status(struct sev_issue_cmd * argp)1780 static int sev_ioctl_do_platform_status(struct sev_issue_cmd *argp)
1781 {
1782 	struct sev_user_data_status data;
1783 	int ret;
1784 
1785 	memset(&data, 0, sizeof(data));
1786 
1787 	ret = __sev_do_cmd_locked(SEV_CMD_PLATFORM_STATUS, &data, &argp->error);
1788 	if (ret)
1789 		return ret;
1790 
1791 	if (copy_to_user((void __user *)argp->data, &data, sizeof(data)))
1792 		ret = -EFAULT;
1793 
1794 	return ret;
1795 }
1796 
sev_ioctl_do_pek_pdh_gen(int cmd,struct sev_issue_cmd * argp,bool writable)1797 static int sev_ioctl_do_pek_pdh_gen(int cmd, struct sev_issue_cmd *argp, bool writable)
1798 {
1799 	struct sev_device *sev = psp_master->sev_data;
1800 	bool shutdown_required = false;
1801 	int rc;
1802 
1803 	if (!writable)
1804 		return -EPERM;
1805 
1806 	if (sev->sev_plat_status.state == SEV_STATE_UNINIT) {
1807 		rc = sev_move_to_init_state(argp, &shutdown_required);
1808 		if (rc)
1809 			return rc;
1810 	}
1811 
1812 	rc = __sev_do_cmd_locked(cmd, NULL, &argp->error);
1813 
1814 	if (shutdown_required)
1815 		__sev_firmware_shutdown(sev, false);
1816 
1817 	return rc;
1818 }
1819 
sev_ioctl_do_pek_csr(struct sev_issue_cmd * argp,bool writable)1820 static int sev_ioctl_do_pek_csr(struct sev_issue_cmd *argp, bool writable)
1821 {
1822 	struct sev_device *sev = psp_master->sev_data;
1823 	struct sev_user_data_pek_csr input;
1824 	bool shutdown_required = false;
1825 	struct sev_data_pek_csr data;
1826 	void __user *input_address;
1827 	void *blob = NULL;
1828 	int ret;
1829 
1830 	if (!writable)
1831 		return -EPERM;
1832 
1833 	if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
1834 		return -EFAULT;
1835 
1836 	memset(&data, 0, sizeof(data));
1837 
1838 	/* userspace wants to query CSR length */
1839 	if (!input.address || !input.length)
1840 		goto cmd;
1841 
1842 	/* allocate a physically contiguous buffer to store the CSR blob */
1843 	input_address = (void __user *)input.address;
1844 	if (input.length > SEV_FW_BLOB_MAX_SIZE)
1845 		return -EFAULT;
1846 
1847 	blob = kzalloc(input.length, GFP_KERNEL);
1848 	if (!blob)
1849 		return -ENOMEM;
1850 
1851 	data.address = __psp_pa(blob);
1852 	data.len = input.length;
1853 
1854 cmd:
1855 	if (sev->sev_plat_status.state == SEV_STATE_UNINIT) {
1856 		ret = sev_move_to_init_state(argp, &shutdown_required);
1857 		if (ret)
1858 			goto e_free_blob;
1859 	}
1860 
1861 	ret = __sev_do_cmd_locked(SEV_CMD_PEK_CSR, &data, &argp->error);
1862 
1863 	 /* If we query the CSR length, FW responded with expected data. */
1864 	input.length = data.len;
1865 
1866 	if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) {
1867 		ret = -EFAULT;
1868 		goto e_free_blob;
1869 	}
1870 
1871 	if (blob) {
1872 		if (copy_to_user(input_address, blob, input.length))
1873 			ret = -EFAULT;
1874 	}
1875 
1876 e_free_blob:
1877 	if (shutdown_required)
1878 		__sev_firmware_shutdown(sev, false);
1879 
1880 	kfree(blob);
1881 	return ret;
1882 }
1883 
psp_copy_user_blob(u64 uaddr,u32 len)1884 void *psp_copy_user_blob(u64 uaddr, u32 len)
1885 {
1886 	if (!uaddr || !len)
1887 		return ERR_PTR(-EINVAL);
1888 
1889 	/* verify that blob length does not exceed our limit */
1890 	if (len > SEV_FW_BLOB_MAX_SIZE)
1891 		return ERR_PTR(-EINVAL);
1892 
1893 	return memdup_user((void __user *)uaddr, len);
1894 }
1895 EXPORT_SYMBOL_GPL(psp_copy_user_blob);
1896 
sev_get_api_version(void)1897 static int sev_get_api_version(void)
1898 {
1899 	struct sev_device *sev = psp_master->sev_data;
1900 	struct sev_user_data_status status;
1901 	int error = 0, ret;
1902 
1903 	/*
1904 	 * Cache SNP platform status and SNP feature information
1905 	 * if SNP is available.
1906 	 */
1907 	if (cc_platform_has(CC_ATTR_HOST_SEV_SNP)) {
1908 		ret = snp_get_platform_data(sev, &error);
1909 		if (ret)
1910 			return 1;
1911 	}
1912 
1913 	ret = sev_platform_status(&status, &error);
1914 	if (ret) {
1915 		dev_err(sev->dev,
1916 			"SEV: failed to get status. Error: %#x\n", error);
1917 		return 1;
1918 	}
1919 
1920 	/* Cache SEV platform status */
1921 	sev->sev_plat_status = status;
1922 
1923 	sev->api_major = status.api_major;
1924 	sev->api_minor = status.api_minor;
1925 	sev->build = status.build;
1926 
1927 	return 0;
1928 }
1929 
sev_get_firmware(struct device * dev,const struct firmware ** firmware)1930 static int sev_get_firmware(struct device *dev,
1931 			    const struct firmware **firmware)
1932 {
1933 	char fw_name_specific[SEV_FW_NAME_SIZE];
1934 	char fw_name_subset[SEV_FW_NAME_SIZE];
1935 
1936 	snprintf(fw_name_specific, sizeof(fw_name_specific),
1937 		 "amd/amd_sev_fam%.2xh_model%.2xh.sbin",
1938 		 boot_cpu_data.x86, boot_cpu_data.x86_model);
1939 
1940 	snprintf(fw_name_subset, sizeof(fw_name_subset),
1941 		 "amd/amd_sev_fam%.2xh_model%.1xxh.sbin",
1942 		 boot_cpu_data.x86, (boot_cpu_data.x86_model & 0xf0) >> 4);
1943 
1944 	/* Check for SEV FW for a particular model.
1945 	 * Ex. amd_sev_fam17h_model00h.sbin for Family 17h Model 00h
1946 	 *
1947 	 * or
1948 	 *
1949 	 * Check for SEV FW common to a subset of models.
1950 	 * Ex. amd_sev_fam17h_model0xh.sbin for
1951 	 *     Family 17h Model 00h -- Family 17h Model 0Fh
1952 	 *
1953 	 * or
1954 	 *
1955 	 * Fall-back to using generic name: sev.fw
1956 	 */
1957 	if ((firmware_request_nowarn(firmware, fw_name_specific, dev) >= 0) ||
1958 	    (firmware_request_nowarn(firmware, fw_name_subset, dev) >= 0) ||
1959 	    (firmware_request_nowarn(firmware, SEV_FW_FILE, dev) >= 0))
1960 		return 0;
1961 
1962 	return -ENOENT;
1963 }
1964 
1965 /* Don't fail if SEV FW couldn't be updated. Continue with existing SEV FW */
sev_update_firmware(struct device * dev)1966 static int sev_update_firmware(struct device *dev)
1967 {
1968 	struct sev_data_download_firmware data;
1969 	const struct firmware *firmware;
1970 	int ret, error, order;
1971 	struct page *p;
1972 	void *fw_blob;
1973 
1974 	if (!sev_version_greater_or_equal(0, 15)) {
1975 		dev_dbg(dev, "DOWNLOAD_FIRMWARE not supported\n");
1976 		return -1;
1977 	}
1978 
1979 	if (sev_get_firmware(dev, &firmware) == -ENOENT) {
1980 		dev_dbg(dev, "No SEV firmware file present\n");
1981 		return -1;
1982 	}
1983 
1984 	order = get_order(firmware->size);
1985 	p = alloc_pages(GFP_KERNEL, order);
1986 	if (!p) {
1987 		ret = -1;
1988 		goto fw_err;
1989 	}
1990 
1991 	/*
1992 	 * Copy firmware data to a kernel allocated contiguous
1993 	 * memory region.
1994 	 */
1995 	fw_blob = page_address(p);
1996 	memcpy(fw_blob, firmware->data, firmware->size);
1997 
1998 	data.address = __psp_pa(fw_blob);
1999 	data.len = firmware->size;
2000 
2001 	ret = sev_do_cmd(SEV_CMD_DOWNLOAD_FIRMWARE, &data, &error);
2002 
2003 	/*
2004 	 * A quirk for fixing the committed TCB version, when upgrading from
2005 	 * earlier firmware version than 1.50.
2006 	 */
2007 	if (!ret && !sev_version_greater_or_equal(1, 50))
2008 		ret = sev_do_cmd(SEV_CMD_DOWNLOAD_FIRMWARE, &data, &error);
2009 
2010 	if (ret)
2011 		dev_dbg(dev, "Failed to update SEV firmware: %#x\n", error);
2012 
2013 	__free_pages(p, order);
2014 
2015 fw_err:
2016 	release_firmware(firmware);
2017 
2018 	return ret;
2019 }
2020 
__sev_snp_shutdown_locked(int * error,bool panic)2021 static int __sev_snp_shutdown_locked(int *error, bool panic)
2022 {
2023 	struct psp_device *psp = psp_master;
2024 	struct sev_device *sev;
2025 	struct sev_data_snp_shutdown_ex data;
2026 	int ret;
2027 
2028 	if (!psp || !psp->sev_data)
2029 		return 0;
2030 
2031 	sev = psp->sev_data;
2032 
2033 	if (!sev->snp_initialized)
2034 		return 0;
2035 
2036 	memset(&data, 0, sizeof(data));
2037 	data.len = sizeof(data);
2038 	data.iommu_snp_shutdown = 1;
2039 	if (sev->snp_feat_info_0.ecx & SNP_X86_SHUTDOWN_SUPPORTED)
2040 		data.x86_snp_shutdown = 1;
2041 
2042 	/*
2043 	 * If invoked during panic handling, local interrupts are disabled
2044 	 * and all CPUs are stopped, so wbinvd_on_all_cpus() can't be called.
2045 	 * In that case, a wbinvd() is done on remote CPUs via the NMI
2046 	 * callback, so only a local wbinvd() is needed here.
2047 	 */
2048 	if (!panic)
2049 		wbinvd_on_all_cpus();
2050 	else
2051 		wbinvd();
2052 
2053 	ret = __sev_do_cmd_locked(SEV_CMD_SNP_SHUTDOWN_EX, &data, error);
2054 	/* SHUTDOWN may require DF_FLUSH */
2055 	if (*error == SEV_RET_DFFLUSH_REQUIRED) {
2056 		int dfflush_error = SEV_RET_NO_FW_CALL;
2057 
2058 		ret = __sev_do_cmd_locked(SEV_CMD_SNP_DF_FLUSH, NULL, &dfflush_error);
2059 		if (ret) {
2060 			dev_err(sev->dev, "SEV-SNP DF_FLUSH failed, ret = %d, error = %#x\n",
2061 				ret, dfflush_error);
2062 			return ret;
2063 		}
2064 		/* reissue the shutdown command */
2065 		ret = __sev_do_cmd_locked(SEV_CMD_SNP_SHUTDOWN_EX, &data,
2066 					  error);
2067 	}
2068 	if (ret) {
2069 		dev_err(sev->dev, "SEV-SNP firmware shutdown failed, rc %d, error %#x\n",
2070 			ret, *error);
2071 		return ret;
2072 	}
2073 
2074 	if (data.x86_snp_shutdown) {
2075 		if (!panic)
2076 			snp_shutdown();
2077 		snp_hv_fixed_pages_state_update(sev, ALLOCATED);
2078 	} else {
2079 		/*
2080 		 * SNP_SHUTDOWN_EX with IOMMU_SNP_SHUTDOWN set to 1 disables SNP
2081 		 * enforcement by the IOMMU and also transitions all pages
2082 		 * associated with the IOMMU to the Reclaim state.
2083 		 * Firmware was transitioning the IOMMU pages to Hypervisor state
2084 		 * before version 1.53. But, accounting for the number of assigned
2085 		 * 4kB pages in a 2M page was done incorrectly by not transitioning
2086 		 * to the Reclaim state. This resulted in RMP #PF when later accessing
2087 		 * the 2M page containing those pages during kexec boot. Hence, the
2088 		 * firmware now transitions these pages to Reclaim state and hypervisor
2089 		 * needs to transition these pages to shared state. SNP Firmware
2090 		 * version 1.53 and above are needed for kexec boot.
2091 		 */
2092 		ret = amd_iommu_snp_disable();
2093 		if (ret) {
2094 			dev_err(sev->dev, "SNP IOMMU shutdown failed\n");
2095 			return ret;
2096 		}
2097 	}
2098 
2099 	snp_leak_hv_fixed_pages();
2100 	sev->snp_initialized = false;
2101 	dev_dbg(sev->dev, "SEV-SNP firmware shutdown\n");
2102 
2103 	/*
2104 	 * __sev_snp_shutdown_locked() deadlocks when it tries to unregister
2105 	 * itself during panic as the panic notifier is called with RCU read
2106 	 * lock held and notifier unregistration does RCU synchronization.
2107 	 */
2108 	if (!panic)
2109 		atomic_notifier_chain_unregister(&panic_notifier_list,
2110 						 &snp_panic_notifier);
2111 
2112 	/* Reset TMR size back to default */
2113 	sev_es_tmr_size = SEV_TMR_SIZE;
2114 
2115 	return ret;
2116 }
2117 
sev_ioctl_do_pek_import(struct sev_issue_cmd * argp,bool writable)2118 static int sev_ioctl_do_pek_import(struct sev_issue_cmd *argp, bool writable)
2119 {
2120 	struct sev_device *sev = psp_master->sev_data;
2121 	struct sev_user_data_pek_cert_import input;
2122 	struct sev_data_pek_cert_import data;
2123 	bool shutdown_required = false;
2124 	void *pek_blob, *oca_blob;
2125 	int ret;
2126 
2127 	if (!writable)
2128 		return -EPERM;
2129 
2130 	if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
2131 		return -EFAULT;
2132 
2133 	/* copy PEK certificate blobs from userspace */
2134 	pek_blob = psp_copy_user_blob(input.pek_cert_address, input.pek_cert_len);
2135 	if (IS_ERR(pek_blob))
2136 		return PTR_ERR(pek_blob);
2137 
2138 	data.reserved = 0;
2139 	data.pek_cert_address = __psp_pa(pek_blob);
2140 	data.pek_cert_len = input.pek_cert_len;
2141 
2142 	/* copy PEK certificate blobs from userspace */
2143 	oca_blob = psp_copy_user_blob(input.oca_cert_address, input.oca_cert_len);
2144 	if (IS_ERR(oca_blob)) {
2145 		ret = PTR_ERR(oca_blob);
2146 		goto e_free_pek;
2147 	}
2148 
2149 	data.oca_cert_address = __psp_pa(oca_blob);
2150 	data.oca_cert_len = input.oca_cert_len;
2151 
2152 	/* If platform is not in INIT state then transition it to INIT */
2153 	if (sev->sev_plat_status.state != SEV_STATE_INIT) {
2154 		ret = sev_move_to_init_state(argp, &shutdown_required);
2155 		if (ret)
2156 			goto e_free_oca;
2157 	}
2158 
2159 	ret = __sev_do_cmd_locked(SEV_CMD_PEK_CERT_IMPORT, &data, &argp->error);
2160 
2161 e_free_oca:
2162 	if (shutdown_required)
2163 		__sev_firmware_shutdown(sev, false);
2164 
2165 	kfree(oca_blob);
2166 e_free_pek:
2167 	kfree(pek_blob);
2168 	return ret;
2169 }
2170 
sev_ioctl_do_get_id2(struct sev_issue_cmd * argp)2171 static int sev_ioctl_do_get_id2(struct sev_issue_cmd *argp)
2172 {
2173 	struct sev_user_data_get_id2 input;
2174 	struct sev_data_get_id data;
2175 	void __user *input_address;
2176 	void *id_blob = NULL;
2177 	int ret;
2178 
2179 	/* SEV GET_ID is available from SEV API v0.16 and up */
2180 	if (!sev_version_greater_or_equal(0, 16))
2181 		return -ENOTSUPP;
2182 
2183 	if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
2184 		return -EFAULT;
2185 
2186 	input_address = (void __user *)input.address;
2187 
2188 	if (input.address && input.length) {
2189 		/*
2190 		 * The length of the ID shouldn't be assumed by software since
2191 		 * it may change in the future.  The allocation size is limited
2192 		 * to 1 << (PAGE_SHIFT + MAX_PAGE_ORDER) by the page allocator.
2193 		 * If the allocation fails, simply return ENOMEM rather than
2194 		 * warning in the kernel log.
2195 		 */
2196 		id_blob = kzalloc(input.length, GFP_KERNEL | __GFP_NOWARN);
2197 		if (!id_blob)
2198 			return -ENOMEM;
2199 
2200 		data.address = __psp_pa(id_blob);
2201 		data.len = input.length;
2202 	} else {
2203 		data.address = 0;
2204 		data.len = 0;
2205 	}
2206 
2207 	ret = __sev_do_cmd_locked(SEV_CMD_GET_ID, &data, &argp->error);
2208 
2209 	/*
2210 	 * Firmware will return the length of the ID value (either the minimum
2211 	 * required length or the actual length written), return it to the user.
2212 	 */
2213 	input.length = data.len;
2214 
2215 	if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) {
2216 		ret = -EFAULT;
2217 		goto e_free;
2218 	}
2219 
2220 	if (id_blob) {
2221 		if (copy_to_user(input_address, id_blob, data.len)) {
2222 			ret = -EFAULT;
2223 			goto e_free;
2224 		}
2225 	}
2226 
2227 e_free:
2228 	kfree(id_blob);
2229 
2230 	return ret;
2231 }
2232 
sev_ioctl_do_get_id(struct sev_issue_cmd * argp)2233 static int sev_ioctl_do_get_id(struct sev_issue_cmd *argp)
2234 {
2235 	struct sev_data_get_id *data;
2236 	u64 data_size, user_size;
2237 	void *id_blob, *mem;
2238 	int ret;
2239 
2240 	/* SEV GET_ID available from SEV API v0.16 and up */
2241 	if (!sev_version_greater_or_equal(0, 16))
2242 		return -ENOTSUPP;
2243 
2244 	/* SEV FW expects the buffer it fills with the ID to be
2245 	 * 8-byte aligned. Memory allocated should be enough to
2246 	 * hold data structure + alignment padding + memory
2247 	 * where SEV FW writes the ID.
2248 	 */
2249 	data_size = ALIGN(sizeof(struct sev_data_get_id), 8);
2250 	user_size = sizeof(struct sev_user_data_get_id);
2251 
2252 	mem = kzalloc(data_size + user_size, GFP_KERNEL);
2253 	if (!mem)
2254 		return -ENOMEM;
2255 
2256 	data = mem;
2257 	id_blob = mem + data_size;
2258 
2259 	data->address = __psp_pa(id_blob);
2260 	data->len = user_size;
2261 
2262 	ret = __sev_do_cmd_locked(SEV_CMD_GET_ID, data, &argp->error);
2263 	if (!ret) {
2264 		if (copy_to_user((void __user *)argp->data, id_blob, data->len))
2265 			ret = -EFAULT;
2266 	}
2267 
2268 	kfree(mem);
2269 
2270 	return ret;
2271 }
2272 
sev_ioctl_do_pdh_export(struct sev_issue_cmd * argp,bool writable)2273 static int sev_ioctl_do_pdh_export(struct sev_issue_cmd *argp, bool writable)
2274 {
2275 	struct sev_device *sev = psp_master->sev_data;
2276 	struct sev_user_data_pdh_cert_export input;
2277 	void *pdh_blob = NULL, *cert_blob = NULL;
2278 	struct sev_data_pdh_cert_export data;
2279 	void __user *input_cert_chain_address;
2280 	void __user *input_pdh_cert_address;
2281 	bool shutdown_required = false;
2282 	int ret;
2283 
2284 	if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
2285 		return -EFAULT;
2286 
2287 	memset(&data, 0, sizeof(data));
2288 
2289 	input_pdh_cert_address = (void __user *)input.pdh_cert_address;
2290 	input_cert_chain_address = (void __user *)input.cert_chain_address;
2291 
2292 	/* Userspace wants to query the certificate length. */
2293 	if (!input.pdh_cert_address ||
2294 	    !input.pdh_cert_len ||
2295 	    !input.cert_chain_address)
2296 		goto cmd;
2297 
2298 	/* Allocate a physically contiguous buffer to store the PDH blob. */
2299 	if (input.pdh_cert_len > SEV_FW_BLOB_MAX_SIZE)
2300 		return -EFAULT;
2301 
2302 	/* Allocate a physically contiguous buffer to store the cert chain blob. */
2303 	if (input.cert_chain_len > SEV_FW_BLOB_MAX_SIZE)
2304 		return -EFAULT;
2305 
2306 	pdh_blob = kzalloc(input.pdh_cert_len, GFP_KERNEL);
2307 	if (!pdh_blob)
2308 		return -ENOMEM;
2309 
2310 	data.pdh_cert_address = __psp_pa(pdh_blob);
2311 	data.pdh_cert_len = input.pdh_cert_len;
2312 
2313 	cert_blob = kzalloc(input.cert_chain_len, GFP_KERNEL);
2314 	if (!cert_blob) {
2315 		ret = -ENOMEM;
2316 		goto e_free_pdh;
2317 	}
2318 
2319 	data.cert_chain_address = __psp_pa(cert_blob);
2320 	data.cert_chain_len = input.cert_chain_len;
2321 
2322 cmd:
2323 	/* If platform is not in INIT state then transition it to INIT. */
2324 	if (sev->sev_plat_status.state != SEV_STATE_INIT) {
2325 		if (!writable) {
2326 			ret = -EPERM;
2327 			goto e_free_cert;
2328 		}
2329 		ret = sev_move_to_init_state(argp, &shutdown_required);
2330 		if (ret)
2331 			goto e_free_cert;
2332 	}
2333 
2334 	ret = __sev_do_cmd_locked(SEV_CMD_PDH_CERT_EXPORT, &data, &argp->error);
2335 
2336 	/* If we query the length, FW responded with expected data. */
2337 	input.cert_chain_len = data.cert_chain_len;
2338 	input.pdh_cert_len = data.pdh_cert_len;
2339 
2340 	if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) {
2341 		ret = -EFAULT;
2342 		goto e_free_cert;
2343 	}
2344 
2345 	if (pdh_blob) {
2346 		if (copy_to_user(input_pdh_cert_address,
2347 				 pdh_blob, input.pdh_cert_len)) {
2348 			ret = -EFAULT;
2349 			goto e_free_cert;
2350 		}
2351 	}
2352 
2353 	if (cert_blob) {
2354 		if (copy_to_user(input_cert_chain_address,
2355 				 cert_blob, input.cert_chain_len))
2356 			ret = -EFAULT;
2357 	}
2358 
2359 e_free_cert:
2360 	if (shutdown_required)
2361 		__sev_firmware_shutdown(sev, false);
2362 
2363 	kfree(cert_blob);
2364 e_free_pdh:
2365 	kfree(pdh_blob);
2366 	return ret;
2367 }
2368 
sev_ioctl_do_snp_platform_status(struct sev_issue_cmd * argp)2369 static int sev_ioctl_do_snp_platform_status(struct sev_issue_cmd *argp)
2370 {
2371 	struct sev_device *sev = psp_master->sev_data;
2372 	struct sev_data_snp_addr buf;
2373 	struct page *status_page;
2374 	void *data;
2375 	int ret;
2376 
2377 	if (!argp->data)
2378 		return -EINVAL;
2379 
2380 	status_page = alloc_page(GFP_KERNEL_ACCOUNT);
2381 	if (!status_page)
2382 		return -ENOMEM;
2383 
2384 	data = page_address(status_page);
2385 
2386 	/*
2387 	 * SNP_PLATFORM_STATUS can be executed in any SNP state. But if executed
2388 	 * when SNP has been initialized, the status page must be firmware-owned.
2389 	 */
2390 	if (sev->snp_initialized) {
2391 		/*
2392 		 * Firmware expects the status page to be in Firmware state,
2393 		 * otherwise it will report an error INVALID_PAGE_STATE.
2394 		 */
2395 		if (rmp_mark_pages_firmware(__pa(data), 1, true)) {
2396 			ret = -EFAULT;
2397 			goto cleanup;
2398 		}
2399 	}
2400 
2401 	buf.address = __psp_pa(data);
2402 	ret = __sev_do_cmd_locked(SEV_CMD_SNP_PLATFORM_STATUS, &buf, &argp->error);
2403 
2404 	if (sev->snp_initialized) {
2405 		/*
2406 		 * The status page will be in Reclaim state on success, or left
2407 		 * in Firmware state on failure. Use snp_reclaim_pages() to
2408 		 * transition either case back to Hypervisor-owned state.
2409 		 */
2410 		if (snp_reclaim_pages(__pa(data), 1, true))
2411 			return -EFAULT;
2412 	}
2413 
2414 	if (ret)
2415 		goto cleanup;
2416 
2417 	if (copy_to_user((void __user *)argp->data, data,
2418 			 sizeof(struct sev_user_data_snp_status)))
2419 		ret = -EFAULT;
2420 
2421 cleanup:
2422 	__free_pages(status_page, 0);
2423 	return ret;
2424 }
2425 
sev_ioctl_do_snp_commit(struct sev_issue_cmd * argp)2426 static int sev_ioctl_do_snp_commit(struct sev_issue_cmd *argp)
2427 {
2428 	struct sev_device *sev = psp_master->sev_data;
2429 	struct sev_data_snp_commit buf;
2430 	bool shutdown_required = false;
2431 	int ret, error;
2432 
2433 	if (!sev->snp_initialized) {
2434 		ret = snp_move_to_init_state(argp, &shutdown_required);
2435 		if (ret)
2436 			return ret;
2437 	}
2438 
2439 	buf.len = sizeof(buf);
2440 
2441 	ret = __sev_do_cmd_locked(SEV_CMD_SNP_COMMIT, &buf, &argp->error);
2442 
2443 	if (shutdown_required)
2444 		__sev_snp_shutdown_locked(&error, false);
2445 
2446 	return ret;
2447 }
2448 
sev_ioctl_do_snp_set_config(struct sev_issue_cmd * argp,bool writable)2449 static int sev_ioctl_do_snp_set_config(struct sev_issue_cmd *argp, bool writable)
2450 {
2451 	struct sev_device *sev = psp_master->sev_data;
2452 	struct sev_user_data_snp_config config;
2453 	bool shutdown_required = false;
2454 	int ret, error;
2455 
2456 	if (!argp->data)
2457 		return -EINVAL;
2458 
2459 	if (!writable)
2460 		return -EPERM;
2461 
2462 	if (copy_from_user(&config, (void __user *)argp->data, sizeof(config)))
2463 		return -EFAULT;
2464 
2465 	if (!sev->snp_initialized) {
2466 		ret = snp_move_to_init_state(argp, &shutdown_required);
2467 		if (ret)
2468 			return ret;
2469 	}
2470 
2471 	ret = __sev_do_cmd_locked(SEV_CMD_SNP_CONFIG, &config, &argp->error);
2472 
2473 	if (shutdown_required)
2474 		__sev_snp_shutdown_locked(&error, false);
2475 
2476 	return ret;
2477 }
2478 
sev_ioctl_do_snp_vlek_load(struct sev_issue_cmd * argp,bool writable)2479 static int sev_ioctl_do_snp_vlek_load(struct sev_issue_cmd *argp, bool writable)
2480 {
2481 	struct sev_device *sev = psp_master->sev_data;
2482 	struct sev_user_data_snp_vlek_load input;
2483 	bool shutdown_required = false;
2484 	int ret, error;
2485 	void *blob;
2486 
2487 	if (!argp->data)
2488 		return -EINVAL;
2489 
2490 	if (!writable)
2491 		return -EPERM;
2492 
2493 	if (copy_from_user(&input, u64_to_user_ptr(argp->data), sizeof(input)))
2494 		return -EFAULT;
2495 
2496 	if (input.len != sizeof(input) || input.vlek_wrapped_version != 0)
2497 		return -EINVAL;
2498 
2499 	blob = psp_copy_user_blob(input.vlek_wrapped_address,
2500 				  sizeof(struct sev_user_data_snp_wrapped_vlek_hashstick));
2501 	if (IS_ERR(blob))
2502 		return PTR_ERR(blob);
2503 
2504 	input.vlek_wrapped_address = __psp_pa(blob);
2505 
2506 	if (!sev->snp_initialized) {
2507 		ret = snp_move_to_init_state(argp, &shutdown_required);
2508 		if (ret)
2509 			goto cleanup;
2510 	}
2511 
2512 	ret = __sev_do_cmd_locked(SEV_CMD_SNP_VLEK_LOAD, &input, &argp->error);
2513 
2514 	if (shutdown_required)
2515 		__sev_snp_shutdown_locked(&error, false);
2516 
2517 cleanup:
2518 	kfree(blob);
2519 
2520 	return ret;
2521 }
2522 
sev_ioctl(struct file * file,unsigned int ioctl,unsigned long arg)2523 static long sev_ioctl(struct file *file, unsigned int ioctl, unsigned long arg)
2524 {
2525 	void __user *argp = (void __user *)arg;
2526 	struct sev_issue_cmd input;
2527 	int ret = -EFAULT;
2528 	bool writable = file->f_mode & FMODE_WRITE;
2529 
2530 	if (!psp_master || !psp_master->sev_data)
2531 		return -ENODEV;
2532 
2533 	if (ioctl != SEV_ISSUE_CMD)
2534 		return -EINVAL;
2535 
2536 	if (copy_from_user(&input, argp, sizeof(struct sev_issue_cmd)))
2537 		return -EFAULT;
2538 
2539 	if (input.cmd > SEV_MAX)
2540 		return -EINVAL;
2541 
2542 	mutex_lock(&sev_cmd_mutex);
2543 
2544 	switch (input.cmd) {
2545 
2546 	case SEV_FACTORY_RESET:
2547 		ret = sev_ioctl_do_reset(&input, writable);
2548 		break;
2549 	case SEV_PLATFORM_STATUS:
2550 		ret = sev_ioctl_do_platform_status(&input);
2551 		break;
2552 	case SEV_PEK_GEN:
2553 		ret = sev_ioctl_do_pek_pdh_gen(SEV_CMD_PEK_GEN, &input, writable);
2554 		break;
2555 	case SEV_PDH_GEN:
2556 		ret = sev_ioctl_do_pek_pdh_gen(SEV_CMD_PDH_GEN, &input, writable);
2557 		break;
2558 	case SEV_PEK_CSR:
2559 		ret = sev_ioctl_do_pek_csr(&input, writable);
2560 		break;
2561 	case SEV_PEK_CERT_IMPORT:
2562 		ret = sev_ioctl_do_pek_import(&input, writable);
2563 		break;
2564 	case SEV_PDH_CERT_EXPORT:
2565 		ret = sev_ioctl_do_pdh_export(&input, writable);
2566 		break;
2567 	case SEV_GET_ID:
2568 		pr_warn_once("SEV_GET_ID command is deprecated, use SEV_GET_ID2\n");
2569 		ret = sev_ioctl_do_get_id(&input);
2570 		break;
2571 	case SEV_GET_ID2:
2572 		ret = sev_ioctl_do_get_id2(&input);
2573 		break;
2574 	case SNP_PLATFORM_STATUS:
2575 		ret = sev_ioctl_do_snp_platform_status(&input);
2576 		break;
2577 	case SNP_COMMIT:
2578 		ret = sev_ioctl_do_snp_commit(&input);
2579 		break;
2580 	case SNP_SET_CONFIG:
2581 		ret = sev_ioctl_do_snp_set_config(&input, writable);
2582 		break;
2583 	case SNP_VLEK_LOAD:
2584 		ret = sev_ioctl_do_snp_vlek_load(&input, writable);
2585 		break;
2586 	default:
2587 		ret = -EINVAL;
2588 		goto out;
2589 	}
2590 
2591 	if (copy_to_user(argp, &input, sizeof(struct sev_issue_cmd)))
2592 		ret = -EFAULT;
2593 out:
2594 	mutex_unlock(&sev_cmd_mutex);
2595 
2596 	return ret;
2597 }
2598 
2599 static const struct file_operations sev_fops = {
2600 	.owner	= THIS_MODULE,
2601 	.unlocked_ioctl = sev_ioctl,
2602 };
2603 
sev_platform_status(struct sev_user_data_status * data,int * error)2604 int sev_platform_status(struct sev_user_data_status *data, int *error)
2605 {
2606 	return sev_do_cmd(SEV_CMD_PLATFORM_STATUS, data, error);
2607 }
2608 EXPORT_SYMBOL_GPL(sev_platform_status);
2609 
sev_guest_deactivate(struct sev_data_deactivate * data,int * error)2610 int sev_guest_deactivate(struct sev_data_deactivate *data, int *error)
2611 {
2612 	return sev_do_cmd(SEV_CMD_DEACTIVATE, data, error);
2613 }
2614 EXPORT_SYMBOL_GPL(sev_guest_deactivate);
2615 
sev_guest_activate(struct sev_data_activate * data,int * error)2616 int sev_guest_activate(struct sev_data_activate *data, int *error)
2617 {
2618 	return sev_do_cmd(SEV_CMD_ACTIVATE, data, error);
2619 }
2620 EXPORT_SYMBOL_GPL(sev_guest_activate);
2621 
sev_guest_decommission(struct sev_data_decommission * data,int * error)2622 int sev_guest_decommission(struct sev_data_decommission *data, int *error)
2623 {
2624 	return sev_do_cmd(SEV_CMD_DECOMMISSION, data, error);
2625 }
2626 EXPORT_SYMBOL_GPL(sev_guest_decommission);
2627 
sev_guest_df_flush(int * error)2628 int sev_guest_df_flush(int *error)
2629 {
2630 	return sev_do_cmd(SEV_CMD_DF_FLUSH, NULL, error);
2631 }
2632 EXPORT_SYMBOL_GPL(sev_guest_df_flush);
2633 
sev_exit(struct kref * ref)2634 static void sev_exit(struct kref *ref)
2635 {
2636 	misc_deregister(&misc_dev->misc);
2637 	kfree(misc_dev);
2638 	misc_dev = NULL;
2639 }
2640 
sev_misc_init(struct sev_device * sev)2641 static int sev_misc_init(struct sev_device *sev)
2642 {
2643 	struct device *dev = sev->dev;
2644 	int ret;
2645 
2646 	/*
2647 	 * SEV feature support can be detected on multiple devices but the SEV
2648 	 * FW commands must be issued on the master. During probe, we do not
2649 	 * know the master hence we create /dev/sev on the first device probe.
2650 	 * sev_do_cmd() finds the right master device to which to issue the
2651 	 * command to the firmware.
2652 	 */
2653 	if (!misc_dev) {
2654 		struct miscdevice *misc;
2655 
2656 		misc_dev = kzalloc_obj(*misc_dev);
2657 		if (!misc_dev)
2658 			return -ENOMEM;
2659 
2660 		misc = &misc_dev->misc;
2661 		misc->minor = MISC_DYNAMIC_MINOR;
2662 		misc->name = DEVICE_NAME;
2663 		misc->fops = &sev_fops;
2664 
2665 		ret = misc_register(misc);
2666 		if (ret)
2667 			return ret;
2668 
2669 		kref_init(&misc_dev->refcount);
2670 	} else {
2671 		kref_get(&misc_dev->refcount);
2672 	}
2673 
2674 	init_waitqueue_head(&sev->int_queue);
2675 	sev->misc = misc_dev;
2676 	dev_dbg(dev, "registered SEV device\n");
2677 
2678 	return 0;
2679 }
2680 
sev_dev_init(struct psp_device * psp)2681 int sev_dev_init(struct psp_device *psp)
2682 {
2683 	struct device *dev = psp->dev;
2684 	struct sev_device *sev;
2685 	int ret = -ENOMEM;
2686 
2687 	if (!boot_cpu_has(X86_FEATURE_SEV)) {
2688 		dev_info_once(dev, "SEV: memory encryption not enabled by BIOS\n");
2689 		return 0;
2690 	}
2691 
2692 	sev = devm_kzalloc(dev, sizeof(*sev), GFP_KERNEL);
2693 	if (!sev)
2694 		goto e_err;
2695 
2696 	sev->cmd_buf = (void *)devm_get_free_pages(dev, GFP_KERNEL, 1);
2697 	if (!sev->cmd_buf)
2698 		goto e_sev;
2699 
2700 	sev->cmd_buf_backup = (uint8_t *)sev->cmd_buf + PAGE_SIZE;
2701 
2702 	psp->sev_data = sev;
2703 
2704 	sev->dev = dev;
2705 	sev->psp = psp;
2706 
2707 	sev->io_regs = psp->io_regs;
2708 
2709 	sev->vdata = (struct sev_vdata *)psp->vdata->sev;
2710 	if (!sev->vdata) {
2711 		ret = -ENODEV;
2712 		dev_err(dev, "sev: missing driver data\n");
2713 		goto e_buf;
2714 	}
2715 
2716 	psp_set_sev_irq_handler(psp, sev_irq_handler, sev);
2717 
2718 	ret = sev_misc_init(sev);
2719 	if (ret)
2720 		goto e_irq;
2721 
2722 	dev_notice(dev, "sev enabled\n");
2723 
2724 	return 0;
2725 
2726 e_irq:
2727 	psp_clear_sev_irq_handler(psp);
2728 e_buf:
2729 	devm_free_pages(dev, (unsigned long)sev->cmd_buf);
2730 e_sev:
2731 	devm_kfree(dev, sev);
2732 e_err:
2733 	psp->sev_data = NULL;
2734 
2735 	dev_notice(dev, "sev initialization failed\n");
2736 
2737 	return ret;
2738 }
2739 
__sev_firmware_shutdown(struct sev_device * sev,bool panic)2740 static void __sev_firmware_shutdown(struct sev_device *sev, bool panic)
2741 {
2742 	int error;
2743 
2744 	__sev_platform_shutdown_locked(&error);
2745 
2746 	if (sev_es_tmr) {
2747 		/*
2748 		 * The TMR area was encrypted, flush it from the cache.
2749 		 *
2750 		 * If invoked during panic handling, local interrupts are
2751 		 * disabled and all CPUs are stopped, so wbinvd_on_all_cpus()
2752 		 * can't be used. In that case, wbinvd() is done on remote CPUs
2753 		 * via the NMI callback, and done for this CPU later during
2754 		 * SNP shutdown, so wbinvd_on_all_cpus() can be skipped.
2755 		 */
2756 		if (!panic)
2757 			wbinvd_on_all_cpus();
2758 
2759 		__snp_free_firmware_pages(virt_to_page(sev_es_tmr),
2760 					  get_order(sev_es_tmr_size),
2761 					  true);
2762 		sev_es_tmr = NULL;
2763 	}
2764 
2765 	if (sev_init_ex_buffer) {
2766 		__snp_free_firmware_pages(virt_to_page(sev_init_ex_buffer),
2767 					  get_order(NV_LENGTH),
2768 					  true);
2769 		sev_init_ex_buffer = NULL;
2770 	}
2771 
2772 	__sev_snp_shutdown_locked(&error, panic);
2773 }
2774 
sev_firmware_shutdown(struct sev_device * sev)2775 static void sev_firmware_shutdown(struct sev_device *sev)
2776 {
2777 	/*
2778 	 * Calling without sev_cmd_mutex held as TSM will likely try disconnecting
2779 	 * IDE and this ends up calling sev_do_cmd() which locks sev_cmd_mutex.
2780 	 */
2781 	if (sev->tio_status)
2782 		sev_tsm_uninit(sev);
2783 
2784 	mutex_lock(&sev_cmd_mutex);
2785 
2786 	__sev_firmware_shutdown(sev, false);
2787 
2788 	kfree(sev->tio_status);
2789 	sev->tio_status = NULL;
2790 
2791 	mutex_unlock(&sev_cmd_mutex);
2792 }
2793 
sev_platform_shutdown(void)2794 void sev_platform_shutdown(void)
2795 {
2796 	if (!psp_master || !psp_master->sev_data)
2797 		return;
2798 
2799 	sev_firmware_shutdown(psp_master->sev_data);
2800 }
2801 EXPORT_SYMBOL_GPL(sev_platform_shutdown);
2802 
sev_get_snp_policy_bits(void)2803 u64 sev_get_snp_policy_bits(void)
2804 {
2805 	struct psp_device *psp = psp_master;
2806 	struct sev_device *sev;
2807 	u64 policy_bits;
2808 
2809 	if (!cc_platform_has(CC_ATTR_HOST_SEV_SNP))
2810 		return 0;
2811 
2812 	if (!psp || !psp->sev_data)
2813 		return 0;
2814 
2815 	sev = psp->sev_data;
2816 
2817 	policy_bits = SNP_POLICY_MASK_BASE;
2818 
2819 	if (sev->snp_plat_status.feature_info) {
2820 		if (sev->snp_feat_info_0.ecx & SNP_RAPL_DISABLE_SUPPORTED)
2821 			policy_bits |= SNP_POLICY_MASK_RAPL_DIS;
2822 
2823 		if (sev->snp_feat_info_0.ecx & SNP_CIPHER_TEXT_HIDING_SUPPORTED)
2824 			policy_bits |= SNP_POLICY_MASK_CIPHERTEXT_HIDING_DRAM;
2825 
2826 		if (sev->snp_feat_info_0.ecx & SNP_AES_256_XTS_POLICY_SUPPORTED)
2827 			policy_bits |= SNP_POLICY_MASK_MEM_AES_256_XTS;
2828 
2829 		if (sev->snp_feat_info_0.ecx & SNP_CXL_ALLOW_POLICY_SUPPORTED)
2830 			policy_bits |= SNP_POLICY_MASK_CXL_ALLOW;
2831 
2832 		if (sev_version_greater_or_equal(1, 58))
2833 			policy_bits |= SNP_POLICY_MASK_PAGE_SWAP_DISABLE;
2834 	}
2835 
2836 	return policy_bits;
2837 }
2838 EXPORT_SYMBOL_GPL(sev_get_snp_policy_bits);
2839 
sev_dev_destroy(struct psp_device * psp)2840 void sev_dev_destroy(struct psp_device *psp)
2841 {
2842 	struct sev_device *sev = psp->sev_data;
2843 
2844 	if (!sev)
2845 		return;
2846 
2847 	sev_firmware_shutdown(sev);
2848 
2849 	if (sev->misc)
2850 		kref_put(&misc_dev->refcount, sev_exit);
2851 
2852 	psp_clear_sev_irq_handler(psp);
2853 }
2854 
snp_shutdown_on_panic(struct notifier_block * nb,unsigned long reason,void * arg)2855 static int snp_shutdown_on_panic(struct notifier_block *nb,
2856 				 unsigned long reason, void *arg)
2857 {
2858 	struct sev_device *sev = psp_master->sev_data;
2859 
2860 	/*
2861 	 * If sev_cmd_mutex is already acquired, then it's likely
2862 	 * another PSP command is in flight and issuing a shutdown
2863 	 * would fail in unexpected ways. Rather than create even
2864 	 * more confusion during a panic, just bail out here.
2865 	 */
2866 	if (mutex_is_locked(&sev_cmd_mutex))
2867 		return NOTIFY_DONE;
2868 
2869 	__sev_firmware_shutdown(sev, true);
2870 
2871 	return NOTIFY_DONE;
2872 }
2873 
sev_issue_cmd_external_user(struct file * filep,unsigned int cmd,void * data,int * error)2874 int sev_issue_cmd_external_user(struct file *filep, unsigned int cmd,
2875 				void *data, int *error)
2876 {
2877 	if (!filep || filep->f_op != &sev_fops)
2878 		return -EBADF;
2879 
2880 	return sev_do_cmd(cmd, data, error);
2881 }
2882 EXPORT_SYMBOL_GPL(sev_issue_cmd_external_user);
2883 
sev_pci_init(void)2884 void sev_pci_init(void)
2885 {
2886 	struct sev_device *sev = psp_master->sev_data;
2887 	u8 api_major, api_minor, build;
2888 
2889 	if (!sev)
2890 		return;
2891 
2892 	psp_timeout = psp_probe_timeout;
2893 
2894 	if (sev_get_api_version())
2895 		goto err;
2896 
2897 	api_major = sev->api_major;
2898 	api_minor = sev->api_minor;
2899 	build     = sev->build;
2900 
2901 	if (sev_update_firmware(sev->dev) == 0)
2902 		sev_get_api_version();
2903 
2904 	if (api_major != sev->api_major || api_minor != sev->api_minor ||
2905 	    build != sev->build)
2906 		dev_info(sev->dev, "SEV firmware updated from %d.%d.%d to %d.%d.%d\n",
2907 			 api_major, api_minor, build,
2908 			 sev->api_major, sev->api_minor, sev->build);
2909 
2910 	return;
2911 
2912 err:
2913 	sev_dev_destroy(psp_master);
2914 
2915 	psp_master->sev_data = NULL;
2916 }
2917 
sev_pci_exit(void)2918 void sev_pci_exit(void)
2919 {
2920 	struct sev_device *sev = psp_master->sev_data;
2921 
2922 	if (!sev)
2923 		return;
2924 
2925 	sev_firmware_shutdown(sev);
2926 }
2927