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15#include "qemu/osdep.h"
16#include "9p.h"
17#include "fsdev/qemu-fsdev.h"
18#include "9p-synth.h"
19#include "qemu/rcu.h"
20#include "qemu/rcu_queue.h"
21#include "qemu/cutils.h"
22#include "sysemu/qtest.h"
23
24
25static V9fsSynthNode synth_root = {
26 .name = "/",
27 .actual_attr = {
28 .mode = 0555 | S_IFDIR,
29 .nlink = 1,
30 },
31 .attr = &synth_root.actual_attr,
32};
33
34static QemuMutex synth_mutex;
35static int synth_node_count;
36
37static int synth_fs;
38
39static V9fsSynthNode *v9fs_add_dir_node(V9fsSynthNode *parent, int mode,
40 const char *name,
41 V9fsSynthNodeAttr *attr, int inode)
42{
43 V9fsSynthNode *node;
44
45
46 mode = ((mode & 0777) | S_IFDIR) & ~(S_IWUSR | S_IWGRP | S_IWOTH);
47 node = g_malloc0(sizeof(V9fsSynthNode));
48 if (attr) {
49
50 node->attr = attr;
51 node->attr->nlink++;
52 } else {
53 node->attr = &node->actual_attr;
54 node->attr->inode = inode;
55 node->attr->nlink = 1;
56
57 node->attr->mode = mode;
58 node->attr->write = NULL;
59 node->attr->read = NULL;
60 }
61 node->private = node;
62 pstrcpy(node->name, sizeof(node->name), name);
63 QLIST_INSERT_HEAD_RCU(&parent->child, node, sibling);
64 return node;
65}
66
67int qemu_v9fs_synth_mkdir(V9fsSynthNode *parent, int mode,
68 const char *name, V9fsSynthNode **result)
69{
70 int ret;
71 V9fsSynthNode *node, *tmp;
72
73 if (!synth_fs) {
74 return EAGAIN;
75 }
76 if (!name || (strlen(name) >= NAME_MAX)) {
77 return EINVAL;
78 }
79 if (!parent) {
80 parent = &synth_root;
81 }
82 qemu_mutex_lock(&synth_mutex);
83 QLIST_FOREACH(tmp, &parent->child, sibling) {
84 if (!strcmp(tmp->name, name)) {
85 ret = EEXIST;
86 goto err_out;
87 }
88 }
89
90 node = v9fs_add_dir_node(parent, mode, name, NULL, synth_node_count++);
91 v9fs_add_dir_node(node, parent->attr->mode, "..",
92 parent->attr, parent->attr->inode);
93 v9fs_add_dir_node(node, node->attr->mode, ".",
94 node->attr, node->attr->inode);
95 *result = node;
96 ret = 0;
97err_out:
98 qemu_mutex_unlock(&synth_mutex);
99 return ret;
100}
101
102int qemu_v9fs_synth_add_file(V9fsSynthNode *parent, int mode,
103 const char *name, v9fs_synth_read read,
104 v9fs_synth_write write, void *arg)
105{
106 int ret;
107 V9fsSynthNode *node, *tmp;
108
109 if (!synth_fs) {
110 return EAGAIN;
111 }
112 if (!name || (strlen(name) >= NAME_MAX)) {
113 return EINVAL;
114 }
115 if (!parent) {
116 parent = &synth_root;
117 }
118
119 qemu_mutex_lock(&synth_mutex);
120 QLIST_FOREACH(tmp, &parent->child, sibling) {
121 if (!strcmp(tmp->name, name)) {
122 ret = EEXIST;
123 goto err_out;
124 }
125 }
126
127 mode = ((mode & 0777) | S_IFREG);
128 node = g_malloc0(sizeof(V9fsSynthNode));
129 node->attr = &node->actual_attr;
130 node->attr->inode = synth_node_count++;
131 node->attr->nlink = 1;
132 node->attr->read = read;
133 node->attr->write = write;
134 node->attr->mode = mode;
135 node->private = arg;
136 pstrcpy(node->name, sizeof(node->name), name);
137 QLIST_INSERT_HEAD_RCU(&parent->child, node, sibling);
138 ret = 0;
139err_out:
140 qemu_mutex_unlock(&synth_mutex);
141 return ret;
142}
143
144static void synth_fill_statbuf(V9fsSynthNode *node, struct stat *stbuf)
145{
146 stbuf->st_dev = 0;
147 stbuf->st_ino = node->attr->inode;
148 stbuf->st_mode = node->attr->mode;
149 stbuf->st_nlink = node->attr->nlink;
150 stbuf->st_uid = 0;
151 stbuf->st_gid = 0;
152 stbuf->st_rdev = 0;
153 stbuf->st_size = 0;
154 stbuf->st_blksize = 0;
155 stbuf->st_blocks = 0;
156 stbuf->st_atime = 0;
157 stbuf->st_mtime = 0;
158 stbuf->st_ctime = 0;
159}
160
161static int synth_lstat(FsContext *fs_ctx,
162 V9fsPath *fs_path, struct stat *stbuf)
163{
164 V9fsSynthNode *node = *(V9fsSynthNode **)fs_path->data;
165
166 synth_fill_statbuf(node, stbuf);
167 return 0;
168}
169
170static int synth_fstat(FsContext *fs_ctx, int fid_type,
171 V9fsFidOpenState *fs, struct stat *stbuf)
172{
173 V9fsSynthOpenState *synth_open = fs->private;
174 synth_fill_statbuf(synth_open->node, stbuf);
175 return 0;
176}
177
178static int synth_opendir(FsContext *ctx,
179 V9fsPath *fs_path, V9fsFidOpenState *fs)
180{
181 V9fsSynthOpenState *synth_open;
182 V9fsSynthNode *node = *(V9fsSynthNode **)fs_path->data;
183
184 synth_open = g_malloc(sizeof(*synth_open));
185 synth_open->node = node;
186 node->open_count++;
187 fs->private = synth_open;
188 return 0;
189}
190
191static int synth_closedir(FsContext *ctx, V9fsFidOpenState *fs)
192{
193 V9fsSynthOpenState *synth_open = fs->private;
194 V9fsSynthNode *node = synth_open->node;
195
196 node->open_count--;
197 g_free(synth_open);
198 fs->private = NULL;
199 return 0;
200}
201
202static off_t synth_telldir(FsContext *ctx, V9fsFidOpenState *fs)
203{
204 V9fsSynthOpenState *synth_open = fs->private;
205 return synth_open->offset;
206}
207
208static void synth_seekdir(FsContext *ctx, V9fsFidOpenState *fs, off_t off)
209{
210 V9fsSynthOpenState *synth_open = fs->private;
211 synth_open->offset = off;
212}
213
214static void synth_rewinddir(FsContext *ctx, V9fsFidOpenState *fs)
215{
216 synth_seekdir(ctx, fs, 0);
217}
218
219static void synth_direntry(V9fsSynthNode *node,
220 struct dirent *entry, off_t off)
221{
222 strcpy(entry->d_name, node->name);
223 entry->d_ino = node->attr->inode;
224 entry->d_off = off + 1;
225}
226
227static struct dirent *synth_get_dentry(V9fsSynthNode *dir,
228 struct dirent *entry, off_t off)
229{
230 int i = 0;
231 V9fsSynthNode *node;
232
233 rcu_read_lock();
234 QLIST_FOREACH(node, &dir->child, sibling) {
235
236 if (i == off) {
237 break;
238 }
239 i++;
240 }
241 rcu_read_unlock();
242 if (!node) {
243
244 return NULL;
245 }
246 synth_direntry(node, entry, off);
247 return entry;
248}
249
250static struct dirent *synth_readdir(FsContext *ctx, V9fsFidOpenState *fs)
251{
252 struct dirent *entry;
253 V9fsSynthOpenState *synth_open = fs->private;
254 V9fsSynthNode *node = synth_open->node;
255 entry = synth_get_dentry(node, &synth_open->dent, synth_open->offset);
256 if (entry) {
257 synth_open->offset++;
258 }
259 return entry;
260}
261
262static int synth_open(FsContext *ctx, V9fsPath *fs_path,
263 int flags, V9fsFidOpenState *fs)
264{
265 V9fsSynthOpenState *synth_open;
266 V9fsSynthNode *node = *(V9fsSynthNode **)fs_path->data;
267
268 synth_open = g_malloc(sizeof(*synth_open));
269 synth_open->node = node;
270 node->open_count++;
271 fs->private = synth_open;
272 return 0;
273}
274
275static int synth_open2(FsContext *fs_ctx, V9fsPath *dir_path,
276 const char *name, int flags,
277 FsCred *credp, V9fsFidOpenState *fs)
278{
279 errno = ENOSYS;
280 return -1;
281}
282
283static int synth_close(FsContext *ctx, V9fsFidOpenState *fs)
284{
285 V9fsSynthOpenState *synth_open = fs->private;
286 V9fsSynthNode *node = synth_open->node;
287
288 node->open_count--;
289 g_free(synth_open);
290 fs->private = NULL;
291 return 0;
292}
293
294static ssize_t synth_pwritev(FsContext *ctx, V9fsFidOpenState *fs,
295 const struct iovec *iov,
296 int iovcnt, off_t offset)
297{
298 int i, count = 0, wcount;
299 V9fsSynthOpenState *synth_open = fs->private;
300 V9fsSynthNode *node = synth_open->node;
301 if (!node->attr->write) {
302 errno = EPERM;
303 return -1;
304 }
305 for (i = 0; i < iovcnt; i++) {
306 wcount = node->attr->write(iov[i].iov_base, iov[i].iov_len,
307 offset, node->private);
308 offset += wcount;
309 count += wcount;
310
311 if (wcount < iov[i].iov_len) {
312 break;
313 }
314 }
315 return count;
316}
317
318static ssize_t synth_preadv(FsContext *ctx, V9fsFidOpenState *fs,
319 const struct iovec *iov,
320 int iovcnt, off_t offset)
321{
322 int i, count = 0, rcount;
323 V9fsSynthOpenState *synth_open = fs->private;
324 V9fsSynthNode *node = synth_open->node;
325 if (!node->attr->read) {
326 errno = EPERM;
327 return -1;
328 }
329 for (i = 0; i < iovcnt; i++) {
330 rcount = node->attr->read(iov[i].iov_base, iov[i].iov_len,
331 offset, node->private);
332 offset += rcount;
333 count += rcount;
334
335 if (rcount < iov[i].iov_len) {
336 break;
337 }
338 }
339 return count;
340}
341
342static int synth_truncate(FsContext *ctx, V9fsPath *path, off_t offset)
343{
344 errno = ENOSYS;
345 return -1;
346}
347
348static int synth_chmod(FsContext *fs_ctx, V9fsPath *path, FsCred *credp)
349{
350 errno = EPERM;
351 return -1;
352}
353
354static int synth_mknod(FsContext *fs_ctx, V9fsPath *path,
355 const char *buf, FsCred *credp)
356{
357 errno = EPERM;
358 return -1;
359}
360
361static int synth_mkdir(FsContext *fs_ctx, V9fsPath *path,
362 const char *buf, FsCred *credp)
363{
364 errno = EPERM;
365 return -1;
366}
367
368static ssize_t synth_readlink(FsContext *fs_ctx, V9fsPath *path,
369 char *buf, size_t bufsz)
370{
371 errno = ENOSYS;
372 return -1;
373}
374
375static int synth_symlink(FsContext *fs_ctx, const char *oldpath,
376 V9fsPath *newpath, const char *buf, FsCred *credp)
377{
378 errno = EPERM;
379 return -1;
380}
381
382static int synth_link(FsContext *fs_ctx, V9fsPath *oldpath,
383 V9fsPath *newpath, const char *buf)
384{
385 errno = EPERM;
386 return -1;
387}
388
389static int synth_rename(FsContext *ctx, const char *oldpath,
390 const char *newpath)
391{
392 errno = EPERM;
393 return -1;
394}
395
396static int synth_chown(FsContext *fs_ctx, V9fsPath *path, FsCred *credp)
397{
398 errno = EPERM;
399 return -1;
400}
401
402static int synth_utimensat(FsContext *fs_ctx, V9fsPath *path,
403 const struct timespec *buf)
404{
405 errno = EPERM;
406 return 0;
407}
408
409static int synth_remove(FsContext *ctx, const char *path)
410{
411 errno = EPERM;
412 return -1;
413}
414
415static int synth_fsync(FsContext *ctx, int fid_type,
416 V9fsFidOpenState *fs, int datasync)
417{
418 errno = ENOSYS;
419 return 0;
420}
421
422static int synth_statfs(FsContext *s, V9fsPath *fs_path,
423 struct statfs *stbuf)
424{
425 stbuf->f_type = 0xABCD;
426 stbuf->f_bsize = 512;
427 stbuf->f_blocks = 0;
428 stbuf->f_files = synth_node_count;
429 stbuf->f_namelen = NAME_MAX;
430 return 0;
431}
432
433static ssize_t synth_lgetxattr(FsContext *ctx, V9fsPath *path,
434 const char *name, void *value, size_t size)
435{
436 errno = ENOTSUP;
437 return -1;
438}
439
440static ssize_t synth_llistxattr(FsContext *ctx, V9fsPath *path,
441 void *value, size_t size)
442{
443 errno = ENOTSUP;
444 return -1;
445}
446
447static int synth_lsetxattr(FsContext *ctx, V9fsPath *path,
448 const char *name, void *value,
449 size_t size, int flags)
450{
451 errno = ENOTSUP;
452 return -1;
453}
454
455static int synth_lremovexattr(FsContext *ctx,
456 V9fsPath *path, const char *name)
457{
458 errno = ENOTSUP;
459 return -1;
460}
461
462static int synth_name_to_path(FsContext *ctx, V9fsPath *dir_path,
463 const char *name, V9fsPath *target)
464{
465 V9fsSynthNode *node;
466 V9fsSynthNode *dir_node;
467
468
469 if (!strcmp(name, ".") || !strcmp(name, "..")) {
470 errno = EINVAL;
471 return -1;
472
473 }
474 if (!dir_path) {
475 dir_node = &synth_root;
476 } else {
477 dir_node = *(V9fsSynthNode **)dir_path->data;
478 }
479 if (!strcmp(name, "/")) {
480 node = dir_node;
481 goto out;
482 }
483
484 rcu_read_lock();
485 QLIST_FOREACH(node, &dir_node->child, sibling) {
486 if (!strcmp(node->name, name)) {
487 break;
488 }
489 }
490 rcu_read_unlock();
491
492 if (!node) {
493 errno = ENOENT;
494 return -1;
495 }
496out:
497
498 g_free(target->data);
499 target->data = g_memdup(&node, sizeof(void *));
500 target->size = sizeof(void *);
501 return 0;
502}
503
504static int synth_renameat(FsContext *ctx, V9fsPath *olddir,
505 const char *old_name, V9fsPath *newdir,
506 const char *new_name)
507{
508 errno = EPERM;
509 return -1;
510}
511
512static int synth_unlinkat(FsContext *ctx, V9fsPath *dir,
513 const char *name, int flags)
514{
515 errno = EPERM;
516 return -1;
517}
518
519static ssize_t v9fs_synth_qtest_write(void *buf, int len, off_t offset,
520 void *arg)
521{
522 return 1;
523}
524
525static ssize_t v9fs_synth_qtest_flush_write(void *buf, int len, off_t offset,
526 void *arg)
527{
528 bool should_block = !!*(uint8_t *)buf;
529
530 if (should_block) {
531
532 errno = EINTR;
533 return -1;
534 }
535
536 return 1;
537}
538
539static int synth_init(FsContext *ctx, Error **errp)
540{
541 QLIST_INIT(&synth_root.child);
542 qemu_mutex_init(&synth_mutex);
543
544
545 v9fs_add_dir_node(&synth_root, synth_root.attr->mode,
546 "..", synth_root.attr, synth_root.attr->inode);
547 v9fs_add_dir_node(&synth_root, synth_root.attr->mode,
548 ".", synth_root.attr, synth_root.attr->inode);
549
550
551 synth_fs = 1;
552
553 if (qtest_enabled()) {
554 V9fsSynthNode *node = NULL;
555 int i, ret;
556
557
558 for (i = 0; i < P9_MAXWELEM; i++) {
559 char *name = g_strdup_printf(QTEST_V9FS_SYNTH_WALK_FILE, i);
560
561 ret = qemu_v9fs_synth_mkdir(node, 0700, name, &node);
562 assert(!ret);
563 g_free(name);
564 }
565
566
567 ret = qemu_v9fs_synth_add_file(NULL, 0, QTEST_V9FS_SYNTH_LOPEN_FILE,
568 NULL, NULL, ctx);
569 assert(!ret);
570
571
572 ret = qemu_v9fs_synth_add_file(NULL, 0, QTEST_V9FS_SYNTH_WRITE_FILE,
573 NULL, v9fs_synth_qtest_write, ctx);
574 assert(!ret);
575
576
577 ret = qemu_v9fs_synth_add_file(NULL, 0, QTEST_V9FS_SYNTH_FLUSH_FILE,
578 NULL, v9fs_synth_qtest_flush_write,
579 ctx);
580 assert(!ret);
581 }
582
583 return 0;
584}
585
586FileOperations synth_ops = {
587 .init = synth_init,
588 .lstat = synth_lstat,
589 .readlink = synth_readlink,
590 .close = synth_close,
591 .closedir = synth_closedir,
592 .open = synth_open,
593 .opendir = synth_opendir,
594 .rewinddir = synth_rewinddir,
595 .telldir = synth_telldir,
596 .readdir = synth_readdir,
597 .seekdir = synth_seekdir,
598 .preadv = synth_preadv,
599 .pwritev = synth_pwritev,
600 .chmod = synth_chmod,
601 .mknod = synth_mknod,
602 .mkdir = synth_mkdir,
603 .fstat = synth_fstat,
604 .open2 = synth_open2,
605 .symlink = synth_symlink,
606 .link = synth_link,
607 .truncate = synth_truncate,
608 .rename = synth_rename,
609 .chown = synth_chown,
610 .utimensat = synth_utimensat,
611 .remove = synth_remove,
612 .fsync = synth_fsync,
613 .statfs = synth_statfs,
614 .lgetxattr = synth_lgetxattr,
615 .llistxattr = synth_llistxattr,
616 .lsetxattr = synth_lsetxattr,
617 .lremovexattr = synth_lremovexattr,
618 .name_to_path = synth_name_to_path,
619 .renameat = synth_renameat,
620 .unlinkat = synth_unlinkat,
621};
622