xref: /freebsd/sys/dev/efidev/efirt.c (revision 0e33efe4e4b5d24e2d416938af8bc6e6e4160ec8)
1 /*-
2  * Copyright (c) 2004 Marcel Moolenaar
3  * Copyright (c) 2001 Doug Rabson
4  * Copyright (c) 2016 The FreeBSD Foundation
5  * All rights reserved.
6  *
7  * Portions of this software were developed by Konstantin Belousov
8  * under sponsorship from the FreeBSD Foundation.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 __FBSDID("$FreeBSD$");
34 
35 #include <sys/param.h>
36 #include <sys/efi.h>
37 #include <sys/kernel.h>
38 #include <sys/linker.h>
39 #include <sys/lock.h>
40 #include <sys/module.h>
41 #include <sys/mutex.h>
42 #include <sys/clock.h>
43 #include <sys/proc.h>
44 #include <sys/rwlock.h>
45 #include <sys/sched.h>
46 #include <sys/sysctl.h>
47 #include <sys/systm.h>
48 #include <sys/vmmeter.h>
49 
50 #include <machine/fpu.h>
51 #include <machine/efi.h>
52 #include <machine/metadata.h>
53 #include <machine/vmparam.h>
54 
55 #include <vm/vm.h>
56 #include <vm/pmap.h>
57 #include <vm/vm_map.h>
58 
59 static struct efi_systbl *efi_systbl;
60 static struct efi_cfgtbl *efi_cfgtbl;
61 static struct efi_rt *efi_runtime;
62 
63 static int efi_status2err[25] = {
64 	0,		/* EFI_SUCCESS */
65 	ENOEXEC,	/* EFI_LOAD_ERROR */
66 	EINVAL,		/* EFI_INVALID_PARAMETER */
67 	ENOSYS,		/* EFI_UNSUPPORTED */
68 	EMSGSIZE, 	/* EFI_BAD_BUFFER_SIZE */
69 	EOVERFLOW,	/* EFI_BUFFER_TOO_SMALL */
70 	EBUSY,		/* EFI_NOT_READY */
71 	EIO,		/* EFI_DEVICE_ERROR */
72 	EROFS,		/* EFI_WRITE_PROTECTED */
73 	EAGAIN,		/* EFI_OUT_OF_RESOURCES */
74 	EIO,		/* EFI_VOLUME_CORRUPTED */
75 	ENOSPC,		/* EFI_VOLUME_FULL */
76 	ENXIO,		/* EFI_NO_MEDIA */
77 	ESTALE,		/* EFI_MEDIA_CHANGED */
78 	ENOENT,		/* EFI_NOT_FOUND */
79 	EACCES,		/* EFI_ACCESS_DENIED */
80 	ETIMEDOUT,	/* EFI_NO_RESPONSE */
81 	EADDRNOTAVAIL,	/* EFI_NO_MAPPING */
82 	ETIMEDOUT,	/* EFI_TIMEOUT */
83 	EDOOFUS,	/* EFI_NOT_STARTED */
84 	EALREADY,	/* EFI_ALREADY_STARTED */
85 	ECANCELED,	/* EFI_ABORTED */
86 	EPROTO,		/* EFI_ICMP_ERROR */
87 	EPROTO,		/* EFI_TFTP_ERROR */
88 	EPROTO		/* EFI_PROTOCOL_ERROR */
89 };
90 
91 static int
92 efi_status_to_errno(efi_status status)
93 {
94 	u_long code;
95 
96 	code = status & 0x3ffffffffffffffful;
97 	return (code < nitems(efi_status2err) ? efi_status2err[code] : EDOOFUS);
98 }
99 
100 static struct mtx efi_lock;
101 
102 static bool
103 efi_is_in_map(struct efi_md *map, int ndesc, int descsz, vm_offset_t addr)
104 {
105 	struct efi_md *p;
106 	int i;
107 
108 	for (i = 0, p = map; i < ndesc; i++, p = efi_next_descriptor(p,
109 	    descsz)) {
110 		if ((p->md_attr & EFI_MD_ATTR_RT) == 0)
111 			continue;
112 
113 		if (addr >= (uintptr_t)p->md_virt &&
114 		    addr < (uintptr_t)p->md_virt + p->md_pages * PAGE_SIZE)
115 			return (true);
116 	}
117 
118 	return (false);
119 }
120 
121 static int
122 efi_init(void)
123 {
124 	struct efi_map_header *efihdr;
125 	struct efi_md *map;
126 	caddr_t kmdp;
127 	size_t efisz;
128 
129 	mtx_init(&efi_lock, "efi", NULL, MTX_DEF);
130 
131 	if (efi_systbl_phys == 0) {
132 		if (bootverbose)
133 			printf("EFI systbl not available\n");
134 		return (0);
135 	}
136 	if (!PMAP_HAS_DMAP) {
137 		if (bootverbose)
138 			printf("EFI systbl requires direct map\n");
139 		return (0);
140 	}
141 	efi_systbl = (struct efi_systbl *)PHYS_TO_DMAP(efi_systbl_phys);
142 	if (efi_systbl->st_hdr.th_sig != EFI_SYSTBL_SIG) {
143 		efi_systbl = NULL;
144 		if (bootverbose)
145 			printf("EFI systbl signature invalid\n");
146 		return (0);
147 	}
148 	efi_cfgtbl = (efi_systbl->st_cfgtbl == 0) ? NULL :
149 	    (struct efi_cfgtbl *)efi_systbl->st_cfgtbl;
150 	if (efi_cfgtbl == NULL) {
151 		if (bootverbose)
152 			printf("EFI config table is not present\n");
153 	}
154 
155 	kmdp = preload_search_by_type("elf kernel");
156 	if (kmdp == NULL)
157 		kmdp = preload_search_by_type("elf64 kernel");
158 	efihdr = (struct efi_map_header *)preload_search_info(kmdp,
159 	    MODINFO_METADATA | MODINFOMD_EFI_MAP);
160 	if (efihdr == NULL) {
161 		if (bootverbose)
162 			printf("EFI map is not present\n");
163 		return (0);
164 	}
165 	efisz = (sizeof(struct efi_map_header) + 0xf) & ~0xf;
166 	map = (struct efi_md *)((uint8_t *)efihdr + efisz);
167 	if (efihdr->descriptor_size == 0)
168 		return (ENOMEM);
169 
170 	if (!efi_create_1t1_map(map, efihdr->memory_size /
171 	    efihdr->descriptor_size, efihdr->descriptor_size)) {
172 		if (bootverbose)
173 			printf("EFI cannot create runtime map\n");
174 		return (ENOMEM);
175 	}
176 
177 	efi_runtime = (efi_systbl->st_rt == 0) ? NULL :
178 	    (struct efi_rt *)efi_systbl->st_rt;
179 	if (efi_runtime == NULL) {
180 		if (bootverbose)
181 			printf("EFI runtime services table is not present\n");
182 		efi_destroy_1t1_map();
183 		return (ENXIO);
184 	}
185 
186 	/*
187 	 * Some UEFI implementations have multiple implementations of the
188 	 * RS->GetTime function. They switch from one we can only use early
189 	 * in the boot process to one valid as a RunTime service only when we
190 	 * call RS->SetVirtualAddressMap. As this is not always the case, e.g.
191 	 * with an old loader.efi, check if the RS->GetTime function is within
192 	 * the EFI map, and fail to attach if not.
193 	 */
194 	if (!efi_is_in_map(map, efihdr->memory_size / efihdr->descriptor_size,
195 	    efihdr->descriptor_size, (vm_offset_t)efi_runtime->rt_gettime)) {
196 		if (bootverbose)
197 			printf(
198 			 "EFI runtime services table has an invalid pointer\n");
199 		efi_runtime = NULL;
200 		efi_destroy_1t1_map();
201 		return (ENXIO);
202 	}
203 
204 	return (0);
205 }
206 
207 static void
208 efi_uninit(void)
209 {
210 
211 	efi_destroy_1t1_map();
212 
213 	efi_systbl = NULL;
214 	efi_cfgtbl = NULL;
215 	efi_runtime = NULL;
216 
217 	mtx_destroy(&efi_lock);
218 }
219 
220 int
221 efi_rt_ok(void)
222 {
223 
224 	if (efi_runtime == NULL)
225 		return (ENXIO);
226 	return (0);
227 }
228 
229 static int
230 efi_enter(void)
231 {
232 	struct thread *td;
233 	pmap_t curpmap;
234 
235 	if (efi_runtime == NULL)
236 		return (ENXIO);
237 	td = curthread;
238 	curpmap = &td->td_proc->p_vmspace->vm_pmap;
239 	PMAP_LOCK(curpmap);
240 	mtx_lock(&efi_lock);
241 	fpu_kern_enter(td, NULL, FPU_KERN_NOCTX);
242 	return (efi_arch_enter());
243 }
244 
245 static void
246 efi_leave(void)
247 {
248 	struct thread *td;
249 	pmap_t curpmap;
250 
251 	efi_arch_leave();
252 
253 	curpmap = &curproc->p_vmspace->vm_pmap;
254 	td = curthread;
255 	fpu_kern_leave(td, NULL);
256 	mtx_unlock(&efi_lock);
257 	PMAP_UNLOCK(curpmap);
258 }
259 
260 int
261 efi_get_table(struct uuid *uuid, void **ptr)
262 {
263 	struct efi_cfgtbl *ct;
264 	u_long count;
265 
266 	if (efi_cfgtbl == NULL || efi_systbl == NULL)
267 		return (ENXIO);
268 	count = efi_systbl->st_entries;
269 	ct = efi_cfgtbl;
270 	while (count--) {
271 		if (!bcmp(&ct->ct_uuid, uuid, sizeof(*uuid))) {
272 			*ptr = (void *)PHYS_TO_DMAP(ct->ct_data);
273 			return (0);
274 		}
275 		ct++;
276 	}
277 	return (ENOENT);
278 }
279 
280 static int
281 efi_get_time_locked(struct efi_tm *tm, struct efi_tmcap *tmcap)
282 {
283 	efi_status status;
284 	int error;
285 
286 	EFI_TIME_OWNED()
287 	error = efi_enter();
288 	if (error != 0)
289 		return (error);
290 	status = efi_runtime->rt_gettime(tm, tmcap);
291 	efi_leave();
292 	error = efi_status_to_errno(status);
293 	return (error);
294 }
295 
296 int
297 efi_get_time(struct efi_tm *tm)
298 {
299 	struct efi_tmcap dummy;
300 	int error;
301 
302 	if (efi_runtime == NULL)
303 		return (ENXIO);
304 	EFI_TIME_LOCK()
305 	/*
306 	 * UEFI spec states that the Capabilities argument to GetTime is
307 	 * optional, but some UEFI implementations choke when passed a NULL
308 	 * pointer. Pass a dummy efi_tmcap, even though we won't use it,
309 	 * to workaround such implementations.
310 	 */
311 	error = efi_get_time_locked(tm, &dummy);
312 	EFI_TIME_UNLOCK()
313 	return (error);
314 }
315 
316 int
317 efi_get_time_capabilities(struct efi_tmcap *tmcap)
318 {
319 	struct efi_tm dummy;
320 	int error;
321 
322 	if (efi_runtime == NULL)
323 		return (ENXIO);
324 	EFI_TIME_LOCK()
325 	error = efi_get_time_locked(&dummy, tmcap);
326 	EFI_TIME_UNLOCK()
327 	return (error);
328 }
329 
330 int
331 efi_reset_system(void)
332 {
333 	int error;
334 
335 	error = efi_enter();
336 	if (error != 0)
337 		return (error);
338 	efi_runtime->rt_reset(EFI_RESET_WARM, 0, 0, NULL);
339 	efi_leave();
340 	return (EIO);
341 }
342 
343 static int
344 efi_set_time_locked(struct efi_tm *tm)
345 {
346 	efi_status status;
347 	int error;
348 
349 	EFI_TIME_OWNED();
350 	error = efi_enter();
351 	if (error != 0)
352 		return (error);
353 	status = efi_runtime->rt_settime(tm);
354 	efi_leave();
355 	error = efi_status_to_errno(status);
356 	return (error);
357 }
358 
359 int
360 efi_set_time(struct efi_tm *tm)
361 {
362 	int error;
363 
364 	if (efi_runtime == NULL)
365 		return (ENXIO);
366 	EFI_TIME_LOCK()
367 	error = efi_set_time_locked(tm);
368 	EFI_TIME_UNLOCK()
369 	return (error);
370 }
371 
372 int
373 efi_var_get(efi_char *name, struct uuid *vendor, uint32_t *attrib,
374     size_t *datasize, void *data)
375 {
376 	efi_status status;
377 	int error;
378 
379 	error = efi_enter();
380 	if (error != 0)
381 		return (error);
382 	status = efi_runtime->rt_getvar(name, vendor, attrib, datasize, data);
383 	efi_leave();
384 	error = efi_status_to_errno(status);
385 	return (error);
386 }
387 
388 int
389 efi_var_nextname(size_t *namesize, efi_char *name, struct uuid *vendor)
390 {
391 	efi_status status;
392 	int error;
393 
394 	error = efi_enter();
395 	if (error != 0)
396 		return (error);
397 	status = efi_runtime->rt_scanvar(namesize, name, vendor);
398 	efi_leave();
399 	error = efi_status_to_errno(status);
400 	return (error);
401 }
402 
403 int
404 efi_var_set(efi_char *name, struct uuid *vendor, uint32_t attrib,
405     size_t datasize, void *data)
406 {
407 	efi_status status;
408 	int error;
409 
410 	error = efi_enter();
411 	if (error != 0)
412 		return (error);
413 	status = efi_runtime->rt_setvar(name, vendor, attrib, datasize, data);
414 	efi_leave();
415 	error = efi_status_to_errno(status);
416 	return (error);
417 }
418 
419 static int
420 efirt_modevents(module_t m, int event, void *arg __unused)
421 {
422 
423 	switch (event) {
424 	case MOD_LOAD:
425 		return (efi_init());
426 
427 	case MOD_UNLOAD:
428 		efi_uninit();
429 		return (0);
430 
431 	case MOD_SHUTDOWN:
432 		return (0);
433 
434 	default:
435 		return (EOPNOTSUPP);
436 	}
437 }
438 
439 static moduledata_t efirt_moddata = {
440 	.name = "efirt",
441 	.evhand = efirt_modevents,
442 	.priv = NULL,
443 };
444 DECLARE_MODULE(efirt, efirt_moddata, SI_SUB_VM_CONF, SI_ORDER_ANY);
445 MODULE_VERSION(efirt, 1);
446