jcs.org
qemu with hax to log dma reads & writes
jcs.org/2018/11/12/vfio
1/*
2 * Functions to help device tree manipulation using libfdt.
3 * It also provides functions to read entries from device tree proc
4 * interface.
5 *
6 * Copyright 2008 IBM Corporation.
7 * Authors: Jerone Young <jyoung5@us.ibm.com>
8 * Hollis Blanchard <hollisb@us.ibm.com>
9 *
10 * This work is licensed under the GNU GPL license version 2 or later.
11 *
12 */
13
14#include "qemu/osdep.h"
15
16#ifdef CONFIG_LINUX
17#include <dirent.h>
18#endif
19
20#include "qapi/error.h"
21#include "qemu/error-report.h"
22#include "qemu/option.h"
23#include "qemu/bswap.h"
24#include "sysemu/device_tree.h"
25#include "sysemu/sysemu.h"
26#include "hw/loader.h"
27#include "hw/boards.h"
28#include "qemu/config-file.h"
29
30#include <libfdt.h>
31
32#define FDT_MAX_SIZE 0x100000
33
34void *create_device_tree(int *sizep)
35{
36 void *fdt;
37 int ret;
38
39 *sizep = FDT_MAX_SIZE;
40 fdt = g_malloc0(FDT_MAX_SIZE);
41 ret = fdt_create(fdt, FDT_MAX_SIZE);
42 if (ret < 0) {
43 goto fail;
44 }
45 ret = fdt_finish_reservemap(fdt);
46 if (ret < 0) {
47 goto fail;
48 }
49 ret = fdt_begin_node(fdt, "");
50 if (ret < 0) {
51 goto fail;
52 }
53 ret = fdt_end_node(fdt);
54 if (ret < 0) {
55 goto fail;
56 }
57 ret = fdt_finish(fdt);
58 if (ret < 0) {
59 goto fail;
60 }
61 ret = fdt_open_into(fdt, fdt, *sizep);
62 if (ret) {
63 error_report("Unable to copy device tree in memory");
64 exit(1);
65 }
66
67 return fdt;
68fail:
69 error_report("%s Couldn't create dt: %s", __func__, fdt_strerror(ret));
70 exit(1);
71}
72
73void *load_device_tree(const char *filename_path, int *sizep)
74{
75 int dt_size;
76 int dt_file_load_size;
77 int ret;
78 void *fdt = NULL;
79
80 *sizep = 0;
81 dt_size = get_image_size(filename_path);
82 if (dt_size < 0) {
83 error_report("Unable to get size of device tree file '%s'",
84 filename_path);
85 goto fail;
86 }
87 if (dt_size > INT_MAX / 2 - 10000) {
88 error_report("Device tree file '%s' is too large", filename_path);
89 goto fail;
90 }
91
92 /* Expand to 2x size to give enough room for manipulation. */
93 dt_size += 10000;
94 dt_size *= 2;
95 /* First allocate space in qemu for device tree */
96 fdt = g_malloc0(dt_size);
97
98 dt_file_load_size = load_image_size(filename_path, fdt, dt_size);
99 if (dt_file_load_size < 0) {
100 error_report("Unable to open device tree file '%s'",
101 filename_path);
102 goto fail;
103 }
104
105 ret = fdt_open_into(fdt, fdt, dt_size);
106 if (ret) {
107 error_report("Unable to copy device tree in memory");
108 goto fail;
109 }
110
111 /* Check sanity of device tree */
112 if (fdt_check_header(fdt)) {
113 error_report("Device tree file loaded into memory is invalid: %s",
114 filename_path);
115 goto fail;
116 }
117 *sizep = dt_size;
118 return fdt;
119
120fail:
121 g_free(fdt);
122 return NULL;
123}
124
125#ifdef CONFIG_LINUX
126
127#define SYSFS_DT_BASEDIR "/proc/device-tree"
128
129/**
130 * read_fstree: this function is inspired from dtc read_fstree
131 * @fdt: preallocated fdt blob buffer, to be populated
132 * @dirname: directory to scan under SYSFS_DT_BASEDIR
133 * the search is recursive and the tree is searched down to the
134 * leaves (property files).
135 *
136 * the function asserts in case of error
137 */
138static void read_fstree(void *fdt, const char *dirname)
139{
140 DIR *d;
141 struct dirent *de;
142 struct stat st;
143 const char *root_dir = SYSFS_DT_BASEDIR;
144 const char *parent_node;
145
146 if (strstr(dirname, root_dir) != dirname) {
147 error_report("%s: %s must be searched within %s",
148 __func__, dirname, root_dir);
149 exit(1);
150 }
151 parent_node = &dirname[strlen(SYSFS_DT_BASEDIR)];
152
153 d = opendir(dirname);
154 if (!d) {
155 error_report("%s cannot open %s", __func__, dirname);
156 exit(1);
157 }
158
159 while ((de = readdir(d)) != NULL) {
160 char *tmpnam;
161
162 if (!g_strcmp0(de->d_name, ".")
163 || !g_strcmp0(de->d_name, "..")) {
164 continue;
165 }
166
167 tmpnam = g_strdup_printf("%s/%s", dirname, de->d_name);
168
169 if (lstat(tmpnam, &st) < 0) {
170 error_report("%s cannot lstat %s", __func__, tmpnam);
171 exit(1);
172 }
173
174 if (S_ISREG(st.st_mode)) {
175 gchar *val;
176 gsize len;
177
178 if (!g_file_get_contents(tmpnam, &val, &len, NULL)) {
179 error_report("%s not able to extract info from %s",
180 __func__, tmpnam);
181 exit(1);
182 }
183
184 if (strlen(parent_node) > 0) {
185 qemu_fdt_setprop(fdt, parent_node,
186 de->d_name, val, len);
187 } else {
188 qemu_fdt_setprop(fdt, "/", de->d_name, val, len);
189 }
190 g_free(val);
191 } else if (S_ISDIR(st.st_mode)) {
192 char *node_name;
193
194 node_name = g_strdup_printf("%s/%s",
195 parent_node, de->d_name);
196 qemu_fdt_add_subnode(fdt, node_name);
197 g_free(node_name);
198 read_fstree(fdt, tmpnam);
199 }
200
201 g_free(tmpnam);
202 }
203
204 closedir(d);
205}
206
207/* load_device_tree_from_sysfs: extract the dt blob from host sysfs */
208void *load_device_tree_from_sysfs(void)
209{
210 void *host_fdt;
211 int host_fdt_size;
212
213 host_fdt = create_device_tree(&host_fdt_size);
214 read_fstree(host_fdt, SYSFS_DT_BASEDIR);
215 if (fdt_check_header(host_fdt)) {
216 error_report("%s host device tree extracted into memory is invalid",
217 __func__);
218 exit(1);
219 }
220 return host_fdt;
221}
222
223#endif /* CONFIG_LINUX */
224
225static int findnode_nofail(void *fdt, const char *node_path)
226{
227 int offset;
228
229 offset = fdt_path_offset(fdt, node_path);
230 if (offset < 0) {
231 error_report("%s Couldn't find node %s: %s", __func__, node_path,
232 fdt_strerror(offset));
233 exit(1);
234 }
235
236 return offset;
237}
238
239char **qemu_fdt_node_unit_path(void *fdt, const char *name, Error **errp)
240{
241 char *prefix = g_strdup_printf("%s@", name);
242 unsigned int path_len = 16, n = 0;
243 GSList *path_list = NULL, *iter;
244 const char *iter_name;
245 int offset, len, ret;
246 char **path_array;
247
248 offset = fdt_next_node(fdt, -1, NULL);
249
250 while (offset >= 0) {
251 iter_name = fdt_get_name(fdt, offset, &len);
252 if (!iter_name) {
253 offset = len;
254 break;
255 }
256 if (!strcmp(iter_name, name) || g_str_has_prefix(iter_name, prefix)) {
257 char *path;
258
259 path = g_malloc(path_len);
260 while ((ret = fdt_get_path(fdt, offset, path, path_len))
261 == -FDT_ERR_NOSPACE) {
262 path_len += 16;
263 path = g_realloc(path, path_len);
264 }
265 path_list = g_slist_prepend(path_list, path);
266 n++;
267 }
268 offset = fdt_next_node(fdt, offset, NULL);
269 }
270 g_free(prefix);
271
272 if (offset < 0 && offset != -FDT_ERR_NOTFOUND) {
273 error_setg(errp, "%s: abort parsing dt for %s node units: %s",
274 __func__, name, fdt_strerror(offset));
275 for (iter = path_list; iter; iter = iter->next) {
276 g_free(iter->data);
277 }
278 g_slist_free(path_list);
279 return NULL;
280 }
281
282 path_array = g_new(char *, n + 1);
283 path_array[n--] = NULL;
284
285 for (iter = path_list; iter; iter = iter->next) {
286 path_array[n--] = iter->data;
287 }
288
289 g_slist_free(path_list);
290
291 return path_array;
292}
293
294char **qemu_fdt_node_path(void *fdt, const char *name, const char *compat,
295 Error **errp)
296{
297 int offset, len, ret;
298 const char *iter_name;
299 unsigned int path_len = 16, n = 0;
300 GSList *path_list = NULL, *iter;
301 char **path_array;
302
303 offset = fdt_node_offset_by_compatible(fdt, -1, compat);
304
305 while (offset >= 0) {
306 iter_name = fdt_get_name(fdt, offset, &len);
307 if (!iter_name) {
308 offset = len;
309 break;
310 }
311 if (!name || !strcmp(iter_name, name)) {
312 char *path;
313
314 path = g_malloc(path_len);
315 while ((ret = fdt_get_path(fdt, offset, path, path_len))
316 == -FDT_ERR_NOSPACE) {
317 path_len += 16;
318 path = g_realloc(path, path_len);
319 }
320 path_list = g_slist_prepend(path_list, path);
321 n++;
322 }
323 offset = fdt_node_offset_by_compatible(fdt, offset, compat);
324 }
325
326 if (offset < 0 && offset != -FDT_ERR_NOTFOUND) {
327 error_setg(errp, "%s: abort parsing dt for %s/%s: %s",
328 __func__, name, compat, fdt_strerror(offset));
329 for (iter = path_list; iter; iter = iter->next) {
330 g_free(iter->data);
331 }
332 g_slist_free(path_list);
333 return NULL;
334 }
335
336 path_array = g_new(char *, n + 1);
337 path_array[n--] = NULL;
338
339 for (iter = path_list; iter; iter = iter->next) {
340 path_array[n--] = iter->data;
341 }
342
343 g_slist_free(path_list);
344
345 return path_array;
346}
347
348int qemu_fdt_setprop(void *fdt, const char *node_path,
349 const char *property, const void *val, int size)
350{
351 int r;
352
353 r = fdt_setprop(fdt, findnode_nofail(fdt, node_path), property, val, size);
354 if (r < 0) {
355 error_report("%s: Couldn't set %s/%s: %s", __func__, node_path,
356 property, fdt_strerror(r));
357 exit(1);
358 }
359
360 return r;
361}
362
363int qemu_fdt_setprop_cell(void *fdt, const char *node_path,
364 const char *property, uint32_t val)
365{
366 int r;
367
368 r = fdt_setprop_cell(fdt, findnode_nofail(fdt, node_path), property, val);
369 if (r < 0) {
370 error_report("%s: Couldn't set %s/%s = %#08x: %s", __func__,
371 node_path, property, val, fdt_strerror(r));
372 exit(1);
373 }
374
375 return r;
376}
377
378int qemu_fdt_setprop_u64(void *fdt, const char *node_path,
379 const char *property, uint64_t val)
380{
381 val = cpu_to_be64(val);
382 return qemu_fdt_setprop(fdt, node_path, property, &val, sizeof(val));
383}
384
385int qemu_fdt_setprop_string(void *fdt, const char *node_path,
386 const char *property, const char *string)
387{
388 int r;
389
390 r = fdt_setprop_string(fdt, findnode_nofail(fdt, node_path), property, string);
391 if (r < 0) {
392 error_report("%s: Couldn't set %s/%s = %s: %s", __func__,
393 node_path, property, string, fdt_strerror(r));
394 exit(1);
395 }
396
397 return r;
398}
399
400const void *qemu_fdt_getprop(void *fdt, const char *node_path,
401 const char *property, int *lenp, Error **errp)
402{
403 int len;
404 const void *r;
405
406 if (!lenp) {
407 lenp = &len;
408 }
409 r = fdt_getprop(fdt, findnode_nofail(fdt, node_path), property, lenp);
410 if (!r) {
411 error_setg(errp, "%s: Couldn't get %s/%s: %s", __func__,
412 node_path, property, fdt_strerror(*lenp));
413 }
414 return r;
415}
416
417uint32_t qemu_fdt_getprop_cell(void *fdt, const char *node_path,
418 const char *property, int *lenp, Error **errp)
419{
420 int len;
421 const uint32_t *p;
422
423 if (!lenp) {
424 lenp = &len;
425 }
426 p = qemu_fdt_getprop(fdt, node_path, property, lenp, errp);
427 if (!p) {
428 return 0;
429 } else if (*lenp != 4) {
430 error_setg(errp, "%s: %s/%s not 4 bytes long (not a cell?)",
431 __func__, node_path, property);
432 *lenp = -EINVAL;
433 return 0;
434 }
435 return be32_to_cpu(*p);
436}
437
438uint32_t qemu_fdt_get_phandle(void *fdt, const char *path)
439{
440 uint32_t r;
441
442 r = fdt_get_phandle(fdt, findnode_nofail(fdt, path));
443 if (r == 0) {
444 error_report("%s: Couldn't get phandle for %s: %s", __func__,
445 path, fdt_strerror(r));
446 exit(1);
447 }
448
449 return r;
450}
451
452int qemu_fdt_setprop_phandle(void *fdt, const char *node_path,
453 const char *property,
454 const char *target_node_path)
455{
456 uint32_t phandle = qemu_fdt_get_phandle(fdt, target_node_path);
457 return qemu_fdt_setprop_cell(fdt, node_path, property, phandle);
458}
459
460uint32_t qemu_fdt_alloc_phandle(void *fdt)
461{
462 static int phandle = 0x0;
463
464 /*
465 * We need to find out if the user gave us special instruction at
466 * which phandle id to start allocating phandles.
467 */
468 if (!phandle) {
469 phandle = machine_phandle_start(current_machine);
470 }
471
472 if (!phandle) {
473 /*
474 * None or invalid phandle given on the command line, so fall back to
475 * default starting point.
476 */
477 phandle = 0x8000;
478 }
479
480 return phandle++;
481}
482
483int qemu_fdt_nop_node(void *fdt, const char *node_path)
484{
485 int r;
486
487 r = fdt_nop_node(fdt, findnode_nofail(fdt, node_path));
488 if (r < 0) {
489 error_report("%s: Couldn't nop node %s: %s", __func__, node_path,
490 fdt_strerror(r));
491 exit(1);
492 }
493
494 return r;
495}
496
497int qemu_fdt_add_subnode(void *fdt, const char *name)
498{
499 char *dupname = g_strdup(name);
500 char *basename = strrchr(dupname, '/');
501 int retval;
502 int parent = 0;
503
504 if (!basename) {
505 g_free(dupname);
506 return -1;
507 }
508
509 basename[0] = '\0';
510 basename++;
511
512 if (dupname[0]) {
513 parent = findnode_nofail(fdt, dupname);
514 }
515
516 retval = fdt_add_subnode(fdt, parent, basename);
517 if (retval < 0) {
518 error_report("FDT: Failed to create subnode %s: %s", name,
519 fdt_strerror(retval));
520 exit(1);
521 }
522
523 g_free(dupname);
524 return retval;
525}
526
527void qemu_fdt_dumpdtb(void *fdt, int size)
528{
529 const char *dumpdtb = qemu_opt_get(qemu_get_machine_opts(), "dumpdtb");
530
531 if (dumpdtb) {
532 /* Dump the dtb to a file and quit */
533 if (g_file_set_contents(dumpdtb, fdt, size, NULL)) {
534 info_report("dtb dumped to %s. Exiting.", dumpdtb);
535 exit(0);
536 }
537 error_report("%s: Failed dumping dtb to %s", __func__, dumpdtb);
538 exit(1);
539 }
540}
541
542int qemu_fdt_setprop_sized_cells_from_array(void *fdt,
543 const char *node_path,
544 const char *property,
545 int numvalues,
546 uint64_t *values)
547{
548 uint32_t *propcells;
549 uint64_t value;
550 int cellnum, vnum, ncells;
551 uint32_t hival;
552 int ret;
553
554 propcells = g_new0(uint32_t, numvalues * 2);
555
556 cellnum = 0;
557 for (vnum = 0; vnum < numvalues; vnum++) {
558 ncells = values[vnum * 2];
559 if (ncells != 1 && ncells != 2) {
560 ret = -1;
561 goto out;
562 }
563 value = values[vnum * 2 + 1];
564 hival = cpu_to_be32(value >> 32);
565 if (ncells > 1) {
566 propcells[cellnum++] = hival;
567 } else if (hival != 0) {
568 ret = -1;
569 goto out;
570 }
571 propcells[cellnum++] = cpu_to_be32(value);
572 }
573
574 ret = qemu_fdt_setprop(fdt, node_path, property, propcells,
575 cellnum * sizeof(uint32_t));
576out:
577 g_free(propcells);
578 return ret;
579}