hw/9pfs/cofs.c

   1
   2 /*
   3  * Virtio 9p backend
   4  *
   5  * Copyright IBM, Corp. 2011
   6  *
   7  * Authors:
   8  *  Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
   9  *
  10  * This work is licensed under the terms of the GNU GPL, version 2.  See
  11  * the COPYING file in the top-level directory.
  12  *
  13  */
  14
  15 #include "fsdev/qemu-fsdev.h"
  16 #include "qemu/thread.h"
  17 #include "block/coroutine.h"
  18 #include "virtio-9p-coth.h"
  19
  20 int v9fs_co_readlink(V9fsPDU *pdu, V9fsPath *path, V9fsString *buf)
  21 {
  22     int err;
  23     ssize_t len;
  24     V9fsState *s = pdu->s;
  25
  26     if (v9fs_request_cancelled(pdu)) {
  27         return -EINTR;
  28     }
  29     buf->data = g_malloc(PATH_MAX);
  30     v9fs_path_read_lock(s);
  31     v9fs_co_run_in_worker(
  32         {
  33             len = s->ops->readlink(&s->ctx, path,
  34                                    buf->data, PATH_MAX - 1);
  35             if (len > -1) {
  36                 buf->size = len;
  37                 buf->data[len] = 0;
  38                 err = 0;
  39             } else {
  40                 err = -errno;
  41             }
  42         });
  43     v9fs_path_unlock(s);
  44     if (err) {
  45         g_free(buf->data);
  46         buf->data = NULL;
  47         buf->size = 0;
  48     }
  49     return err;
  50 }
  51
  52 int v9fs_co_statfs(V9fsPDU *pdu, V9fsPath *path, struct statfs *stbuf)
  53 {
  54     int err;
  55     V9fsState *s = pdu->s;
  56
  57     if (v9fs_request_cancelled(pdu)) {
  58         return -EINTR;
  59     }
  60     v9fs_path_read_lock(s);
  61     v9fs_co_run_in_worker(
  62         {
  63             err = s->ops->statfs(&s->ctx, path, stbuf);
  64             if (err < 0) {
  65                 err = -errno;
  66             }
  67         });
  68     v9fs_path_unlock(s);
  69     return err;
  70 }
  71
  72 int v9fs_co_chmod(V9fsPDU *pdu, V9fsPath *path, mode_t mode)
  73 {
  74     int err;
  75     FsCred cred;
  76     V9fsState *s = pdu->s;
  77
  78     if (v9fs_request_cancelled(pdu)) {
  79         return -EINTR;
  80     }
  81     cred_init(&cred);
  82     cred.fc_mode = mode;
  83     v9fs_path_read_lock(s);
  84     v9fs_co_run_in_worker(
  85         {
  86             err = s->ops->chmod(&s->ctx, path, &cred);
  87             if (err < 0) {
  88                 err = -errno;
  89             }
  90         });
  91     v9fs_path_unlock(s);
  92     return err;
  93 }
  94
  95 int v9fs_co_utimensat(V9fsPDU *pdu, V9fsPath *path,
  96                       struct timespec times[2])
  97 {
  98     int err;
  99     V9fsState *s = pdu->s;
 100
 101     if (v9fs_request_cancelled(pdu)) {
 102         return -EINTR;
 103     }
 104     v9fs_path_read_lock(s);
 105     v9fs_co_run_in_worker(
 106         {
 107             err = s->ops->utimensat(&s->ctx, path, times);
 108             if (err < 0) {
 109                 err = -errno;
 110             }
 111         });
 112     v9fs_path_unlock(s);
 113     return err;
 114 }
 115
 116 int v9fs_co_chown(V9fsPDU *pdu, V9fsPath *path, uid_t uid, gid_t gid)
 117 {
 118     int err;
 119     FsCred cred;
 120     V9fsState *s = pdu->s;
 121
 122     if (v9fs_request_cancelled(pdu)) {
 123         return -EINTR;
 124     }
 125     cred_init(&cred);
 126     cred.fc_uid = uid;
 127     cred.fc_gid = gid;
 128     v9fs_path_read_lock(s);
 129     v9fs_co_run_in_worker(
 130         {
 131             err = s->ops->chown(&s->ctx, path, &cred);
 132             if (err < 0) {
 133                 err = -errno;
 134             }
 135         });
 136     v9fs_path_unlock(s);
 137     return err;
 138 }
 139
 140 int v9fs_co_truncate(V9fsPDU *pdu, V9fsPath *path, off_t size)
 141 {
 142     int err;
 143     V9fsState *s = pdu->s;
 144
 145     if (v9fs_request_cancelled(pdu)) {
 146         return -EINTR;
 147     }
 148     v9fs_path_read_lock(s);
 149     v9fs_co_run_in_worker(
 150         {
 151             err = s->ops->truncate(&s->ctx, path, size);
 152             if (err < 0) {
 153                 err = -errno;
 154             }
 155         });
 156     v9fs_path_unlock(s);
 157     return err;
 158 }
 159
 160 int v9fs_co_mknod(V9fsPDU *pdu, V9fsFidState *fidp, V9fsString *name, uid_t uid,
 161                   gid_t gid, dev_t dev, mode_t mode, struct stat *stbuf)
 162 {
 163     int err;
 164     V9fsPath path;
 165     FsCred cred;
 166     V9fsState *s = pdu->s;
 167
 168     if (v9fs_request_cancelled(pdu)) {
 169         return -EINTR;
 170     }
 171     cred_init(&cred);
 172     cred.fc_uid  = uid;
 173     cred.fc_gid  = gid;
 174     cred.fc_mode = mode;
 175     cred.fc_rdev = dev;
 176     v9fs_path_read_lock(s);
 177     v9fs_co_run_in_worker(
 178         {
 179             err = s->ops->mknod(&s->ctx, &fidp->path, name->data, &cred);
 180             if (err < 0) {
 181                 err = -errno;
 182             } else {
 183                 v9fs_path_init(&path);
 184                 err = v9fs_name_to_path(s, &fidp->path, name->data, &path);
 185                 if (!err) {
 186                     err = s->ops->lstat(&s->ctx, &path, stbuf);
 187                     if (err < 0) {
 188                         err = -errno;
 189                     }
 190                 }
 191                 v9fs_path_free(&path);
 192             }
 193         });
 194     v9fs_path_unlock(s);
 195     return err;
 196 }
 197
 198 /* Only works with path name based fid */
 199 int v9fs_co_remove(V9fsPDU *pdu, V9fsPath *path)
 200 {
 201     int err;
 202     V9fsState *s = pdu->s;
 203
 204     if (v9fs_request_cancelled(pdu)) {
 205         return -EINTR;
 206     }
 207     v9fs_path_read_lock(s);
 208     v9fs_co_run_in_worker(
 209         {
 210             err = s->ops->remove(&s->ctx, path->data);
 211             if (err < 0) {
 212                 err = -errno;
 213             }
 214         });
 215     v9fs_path_unlock(s);
 216     return err;
 217 }
 218
 219 int v9fs_co_unlinkat(V9fsPDU *pdu, V9fsPath *path, V9fsString *name, int flags)
 220 {
 221     int err;
 222     V9fsState *s = pdu->s;
 223
 224     if (v9fs_request_cancelled(pdu)) {
 225         return -EINTR;
 226     }
 227     v9fs_path_read_lock(s);
 228     v9fs_co_run_in_worker(
 229         {
 230             err = s->ops->unlinkat(&s->ctx, path, name->data, flags);
 231             if (err < 0) {
 232                 err = -errno;
 233             }
 234         });
 235     v9fs_path_unlock(s);
 236     return err;
 237 }
 238
 239 /* Only work with path name based fid */
 240 int v9fs_co_rename(V9fsPDU *pdu, V9fsPath *oldpath, V9fsPath *newpath)
 241 {
 242     int err;
 243     V9fsState *s = pdu->s;
 244
 245     if (v9fs_request_cancelled(pdu)) {
 246         return -EINTR;
 247     }
 248     v9fs_co_run_in_worker(
 249         {
 250             err = s->ops->rename(&s->ctx, oldpath->data, newpath->data);
 251             if (err < 0) {
 252                 err = -errno;
 253             }
 254         });
 255     return err;
 256 }
 257
 258 int v9fs_co_renameat(V9fsPDU *pdu, V9fsPath *olddirpath, V9fsString *oldname,
 259                      V9fsPath *newdirpath, V9fsString *newname)
 260 {
 261     int err;
 262     V9fsState *s = pdu->s;
 263
 264     if (v9fs_request_cancelled(pdu)) {
 265         return -EINTR;
 266     }
 267     v9fs_co_run_in_worker(
 268         {
 269             err = s->ops->renameat(&s->ctx, olddirpath, oldname->data,
 270                                    newdirpath, newname->data);
 271             if (err < 0) {
 272                 err = -errno;
 273             }
 274         });
 275     return err;
 276 }
 277
 278 int v9fs_co_symlink(V9fsPDU *pdu, V9fsFidState *dfidp, V9fsString *name,
 279                     const char *oldpath, gid_t gid, struct stat *stbuf)
 280 {
 281     int err;
 282     FsCred cred;
 283     V9fsPath path;
 284     V9fsState *s = pdu->s;
 285
 286     if (v9fs_request_cancelled(pdu)) {
 287         return -EINTR;
 288     }
 289     cred_init(&cred);
 290     cred.fc_uid = dfidp->uid;
 291     cred.fc_gid = gid;
 292     cred.fc_mode = 0777;
 293     v9fs_path_read_lock(s);
 294     v9fs_co_run_in_worker(
 295         {
 296             err = s->ops->symlink(&s->ctx, oldpath, &dfidp->path,
 297                                   name->data, &cred);
 298             if (err < 0) {
 299                 err = -errno;
 300             } else {
 301                 v9fs_path_init(&path);
 302                 err = v9fs_name_to_path(s, &dfidp->path, name->data, &path);
 303                 if (!err) {
 304                     err = s->ops->lstat(&s->ctx, &path, stbuf);
 305                     if (err < 0) {
 306                         err = -errno;
 307                     }
 308                 }
 309                 v9fs_path_free(&path);
 310             }
 311         });
 312     v9fs_path_unlock(s);
 313     return err;
 314 }
 315
 316 /*
 317  * For path name based fid we don't block. So we can
 318  * directly call the fs driver ops.
 319  */
 320 int v9fs_co_name_to_path(V9fsPDU *pdu, V9fsPath *dirpath,
 321                          const char *name, V9fsPath *path)
 322 {
 323     int err;
 324     V9fsState *s = pdu->s;
 325
 326     if (s->ctx.export_flags & V9FS_PATHNAME_FSCONTEXT) {
 327         err = s->ops->name_to_path(&s->ctx, dirpath, name, path);
 328         if (err < 0) {
 329             err = -errno;
 330         }
 331     } else {
 332         if (v9fs_request_cancelled(pdu)) {
 333             return -EINTR;
 334         }
 335         v9fs_co_run_in_worker(
 336             {
 337                 err = s->ops->name_to_path(&s->ctx, dirpath, name, path);
 338                 if (err < 0) {
 339                     err = -errno;
 340                 }
 341             });
 342     }
 343     return err;
 344 }