diff options
Diffstat (limited to 'fs/fuse/dir.c')
| -rw-r--r-- | fs/fuse/dir.c | 982 |
1 files changed, 982 insertions, 0 deletions
diff --git a/fs/fuse/dir.c b/fs/fuse/dir.c new file mode 100644 index 000000000000..e79e49b3eec7 --- /dev/null +++ b/fs/fuse/dir.c | |||
| @@ -0,0 +1,982 @@ | |||
| 1 | /* | ||
| 2 | FUSE: Filesystem in Userspace | ||
| 3 | Copyright (C) 2001-2005 Miklos Szeredi <miklos@szeredi.hu> | ||
| 4 | |||
| 5 | This program can be distributed under the terms of the GNU GPL. | ||
| 6 | See the file COPYING. | ||
| 7 | */ | ||
| 8 | |||
| 9 | #include "fuse_i.h" | ||
| 10 | |||
| 11 | #include <linux/pagemap.h> | ||
| 12 | #include <linux/file.h> | ||
| 13 | #include <linux/gfp.h> | ||
| 14 | #include <linux/sched.h> | ||
| 15 | #include <linux/namei.h> | ||
| 16 | |||
| 17 | static inline unsigned long time_to_jiffies(unsigned long sec, | ||
| 18 | unsigned long nsec) | ||
| 19 | { | ||
| 20 | struct timespec ts = {sec, nsec}; | ||
| 21 | return jiffies + timespec_to_jiffies(&ts); | ||
| 22 | } | ||
| 23 | |||
| 24 | static void fuse_lookup_init(struct fuse_req *req, struct inode *dir, | ||
| 25 | struct dentry *entry, | ||
| 26 | struct fuse_entry_out *outarg) | ||
| 27 | { | ||
| 28 | req->in.h.opcode = FUSE_LOOKUP; | ||
| 29 | req->in.h.nodeid = get_node_id(dir); | ||
| 30 | req->inode = dir; | ||
| 31 | req->in.numargs = 1; | ||
| 32 | req->in.args[0].size = entry->d_name.len + 1; | ||
| 33 | req->in.args[0].value = entry->d_name.name; | ||
| 34 | req->out.numargs = 1; | ||
| 35 | req->out.args[0].size = sizeof(struct fuse_entry_out); | ||
| 36 | req->out.args[0].value = outarg; | ||
| 37 | } | ||
| 38 | |||
| 39 | static int fuse_dentry_revalidate(struct dentry *entry, struct nameidata *nd) | ||
| 40 | { | ||
| 41 | if (!entry->d_inode || is_bad_inode(entry->d_inode)) | ||
| 42 | return 0; | ||
| 43 | else if (time_after(jiffies, entry->d_time)) { | ||
| 44 | int err; | ||
| 45 | struct fuse_entry_out outarg; | ||
| 46 | struct inode *inode = entry->d_inode; | ||
| 47 | struct fuse_inode *fi = get_fuse_inode(inode); | ||
| 48 | struct fuse_conn *fc = get_fuse_conn(inode); | ||
| 49 | struct fuse_req *req = fuse_get_request(fc); | ||
| 50 | if (!req) | ||
| 51 | return 0; | ||
| 52 | |||
| 53 | fuse_lookup_init(req, entry->d_parent->d_inode, entry, &outarg); | ||
| 54 | request_send(fc, req); | ||
| 55 | err = req->out.h.error; | ||
| 56 | if (!err) { | ||
| 57 | if (outarg.nodeid != get_node_id(inode)) { | ||
| 58 | fuse_send_forget(fc, req, outarg.nodeid, 1); | ||
| 59 | return 0; | ||
| 60 | } | ||
| 61 | fi->nlookup ++; | ||
| 62 | } | ||
| 63 | fuse_put_request(fc, req); | ||
| 64 | if (err || (outarg.attr.mode ^ inode->i_mode) & S_IFMT) | ||
| 65 | return 0; | ||
| 66 | |||
| 67 | fuse_change_attributes(inode, &outarg.attr); | ||
| 68 | entry->d_time = time_to_jiffies(outarg.entry_valid, | ||
| 69 | outarg.entry_valid_nsec); | ||
| 70 | fi->i_time = time_to_jiffies(outarg.attr_valid, | ||
| 71 | outarg.attr_valid_nsec); | ||
| 72 | } | ||
| 73 | return 1; | ||
| 74 | } | ||
| 75 | |||
| 76 | static struct dentry_operations fuse_dentry_operations = { | ||
| 77 | .d_revalidate = fuse_dentry_revalidate, | ||
| 78 | }; | ||
| 79 | |||
| 80 | static int fuse_lookup_iget(struct inode *dir, struct dentry *entry, | ||
| 81 | struct inode **inodep) | ||
| 82 | { | ||
| 83 | int err; | ||
| 84 | struct fuse_entry_out outarg; | ||
| 85 | struct inode *inode = NULL; | ||
| 86 | struct fuse_conn *fc = get_fuse_conn(dir); | ||
| 87 | struct fuse_req *req; | ||
| 88 | |||
| 89 | if (entry->d_name.len > FUSE_NAME_MAX) | ||
| 90 | return -ENAMETOOLONG; | ||
| 91 | |||
| 92 | req = fuse_get_request(fc); | ||
| 93 | if (!req) | ||
| 94 | return -EINTR; | ||
| 95 | |||
| 96 | fuse_lookup_init(req, dir, entry, &outarg); | ||
| 97 | request_send(fc, req); | ||
| 98 | err = req->out.h.error; | ||
| 99 | if (!err) { | ||
| 100 | inode = fuse_iget(dir->i_sb, outarg.nodeid, outarg.generation, | ||
| 101 | &outarg.attr); | ||
| 102 | if (!inode) { | ||
| 103 | fuse_send_forget(fc, req, outarg.nodeid, 1); | ||
| 104 | return -ENOMEM; | ||
| 105 | } | ||
| 106 | } | ||
| 107 | fuse_put_request(fc, req); | ||
| 108 | if (err && err != -ENOENT) | ||
| 109 | return err; | ||
| 110 | |||
| 111 | if (inode) { | ||
| 112 | struct fuse_inode *fi = get_fuse_inode(inode); | ||
| 113 | entry->d_time = time_to_jiffies(outarg.entry_valid, | ||
| 114 | outarg.entry_valid_nsec); | ||
| 115 | fi->i_time = time_to_jiffies(outarg.attr_valid, | ||
| 116 | outarg.attr_valid_nsec); | ||
| 117 | } | ||
| 118 | |||
| 119 | entry->d_op = &fuse_dentry_operations; | ||
| 120 | *inodep = inode; | ||
| 121 | return 0; | ||
| 122 | } | ||
| 123 | |||
| 124 | void fuse_invalidate_attr(struct inode *inode) | ||
| 125 | { | ||
| 126 | get_fuse_inode(inode)->i_time = jiffies - 1; | ||
| 127 | } | ||
| 128 | |||
| 129 | static void fuse_invalidate_entry(struct dentry *entry) | ||
| 130 | { | ||
| 131 | d_invalidate(entry); | ||
| 132 | entry->d_time = jiffies - 1; | ||
| 133 | } | ||
| 134 | |||
| 135 | static int create_new_entry(struct fuse_conn *fc, struct fuse_req *req, | ||
| 136 | struct inode *dir, struct dentry *entry, | ||
| 137 | int mode) | ||
| 138 | { | ||
| 139 | struct fuse_entry_out outarg; | ||
| 140 | struct inode *inode; | ||
| 141 | struct fuse_inode *fi; | ||
| 142 | int err; | ||
| 143 | |||
| 144 | req->in.h.nodeid = get_node_id(dir); | ||
| 145 | req->inode = dir; | ||
| 146 | req->out.numargs = 1; | ||
| 147 | req->out.args[0].size = sizeof(outarg); | ||
| 148 | req->out.args[0].value = &outarg; | ||
| 149 | request_send(fc, req); | ||
| 150 | err = req->out.h.error; | ||
| 151 | if (err) { | ||
| 152 | fuse_put_request(fc, req); | ||
| 153 | return err; | ||
| 154 | } | ||
| 155 | inode = fuse_iget(dir->i_sb, outarg.nodeid, outarg.generation, | ||
| 156 | &outarg.attr); | ||
| 157 | if (!inode) { | ||
| 158 | fuse_send_forget(fc, req, outarg.nodeid, 1); | ||
| 159 | return -ENOMEM; | ||
| 160 | } | ||
| 161 | fuse_put_request(fc, req); | ||
| 162 | |||
| 163 | /* Don't allow userspace to do really stupid things... */ | ||
| 164 | if ((inode->i_mode ^ mode) & S_IFMT) { | ||
| 165 | iput(inode); | ||
| 166 | return -EIO; | ||
| 167 | } | ||
| 168 | |||
| 169 | entry->d_time = time_to_jiffies(outarg.entry_valid, | ||
| 170 | outarg.entry_valid_nsec); | ||
| 171 | |||
| 172 | fi = get_fuse_inode(inode); | ||
| 173 | fi->i_time = time_to_jiffies(outarg.attr_valid, | ||
| 174 | outarg.attr_valid_nsec); | ||
| 175 | |||
| 176 | d_instantiate(entry, inode); | ||
| 177 | fuse_invalidate_attr(dir); | ||
| 178 | return 0; | ||
| 179 | } | ||
| 180 | |||
| 181 | static int fuse_mknod(struct inode *dir, struct dentry *entry, int mode, | ||
| 182 | dev_t rdev) | ||
| 183 | { | ||
| 184 | struct fuse_mknod_in inarg; | ||
| 185 | struct fuse_conn *fc = get_fuse_conn(dir); | ||
| 186 | struct fuse_req *req = fuse_get_request(fc); | ||
| 187 | if (!req) | ||
| 188 | return -EINTR; | ||
| 189 | |||
| 190 | memset(&inarg, 0, sizeof(inarg)); | ||
| 191 | inarg.mode = mode; | ||
| 192 | inarg.rdev = new_encode_dev(rdev); | ||
| 193 | req->in.h.opcode = FUSE_MKNOD; | ||
| 194 | req->in.numargs = 2; | ||
| 195 | req->in.args[0].size = sizeof(inarg); | ||
| 196 | req->in.args[0].value = &inarg; | ||
| 197 | req->in.args[1].size = entry->d_name.len + 1; | ||
| 198 | req->in.args[1].value = entry->d_name.name; | ||
| 199 | return create_new_entry(fc, req, dir, entry, mode); | ||
| 200 | } | ||
| 201 | |||
| 202 | static int fuse_create(struct inode *dir, struct dentry *entry, int mode, | ||
| 203 | struct nameidata *nd) | ||
| 204 | { | ||
| 205 | return fuse_mknod(dir, entry, mode, 0); | ||
| 206 | } | ||
| 207 | |||
| 208 | static int fuse_mkdir(struct inode *dir, struct dentry *entry, int mode) | ||
| 209 | { | ||
| 210 | struct fuse_mkdir_in inarg; | ||
| 211 | struct fuse_conn *fc = get_fuse_conn(dir); | ||
| 212 | struct fuse_req *req = fuse_get_request(fc); | ||
| 213 | if (!req) | ||
| 214 | return -EINTR; | ||
| 215 | |||
| 216 | memset(&inarg, 0, sizeof(inarg)); | ||
| 217 | inarg.mode = mode; | ||
| 218 | req->in.h.opcode = FUSE_MKDIR; | ||
| 219 | req->in.numargs = 2; | ||
| 220 | req->in.args[0].size = sizeof(inarg); | ||
| 221 | req->in.args[0].value = &inarg; | ||
| 222 | req->in.args[1].size = entry->d_name.len + 1; | ||
| 223 | req->in.args[1].value = entry->d_name.name; | ||
| 224 | return create_new_entry(fc, req, dir, entry, S_IFDIR); | ||
| 225 | } | ||
| 226 | |||
| 227 | static int fuse_symlink(struct inode *dir, struct dentry *entry, | ||
| 228 | const char *link) | ||
| 229 | { | ||
| 230 | struct fuse_conn *fc = get_fuse_conn(dir); | ||
| 231 | unsigned len = strlen(link) + 1; | ||
| 232 | struct fuse_req *req; | ||
| 233 | |||
| 234 | if (len > FUSE_SYMLINK_MAX) | ||
| 235 | return -ENAMETOOLONG; | ||
| 236 | |||
| 237 | req = fuse_get_request(fc); | ||
| 238 | if (!req) | ||
| 239 | return -EINTR; | ||
| 240 | |||
| 241 | req->in.h.opcode = FUSE_SYMLINK; | ||
| 242 | req->in.numargs = 2; | ||
| 243 | req->in.args[0].size = entry->d_name.len + 1; | ||
| 244 | req->in.args[0].value = entry->d_name.name; | ||
| 245 | req->in.args[1].size = len; | ||
| 246 | req->in.args[1].value = link; | ||
| 247 | return create_new_entry(fc, req, dir, entry, S_IFLNK); | ||
| 248 | } | ||
| 249 | |||
| 250 | static int fuse_unlink(struct inode *dir, struct dentry *entry) | ||
| 251 | { | ||
| 252 | int err; | ||
| 253 | struct fuse_conn *fc = get_fuse_conn(dir); | ||
| 254 | struct fuse_req *req = fuse_get_request(fc); | ||
| 255 | if (!req) | ||
| 256 | return -EINTR; | ||
| 257 | |||
| 258 | req->in.h.opcode = FUSE_UNLINK; | ||
| 259 | req->in.h.nodeid = get_node_id(dir); | ||
| 260 | req->inode = dir; | ||
| 261 | req->in.numargs = 1; | ||
| 262 | req->in.args[0].size = entry->d_name.len + 1; | ||
| 263 | req->in.args[0].value = entry->d_name.name; | ||
| 264 | request_send(fc, req); | ||
| 265 | err = req->out.h.error; | ||
| 266 | fuse_put_request(fc, req); | ||
| 267 | if (!err) { | ||
| 268 | struct inode *inode = entry->d_inode; | ||
| 269 | |||
| 270 | /* Set nlink to zero so the inode can be cleared, if | ||
| 271 | the inode does have more links this will be | ||
| 272 | discovered at the next lookup/getattr */ | ||
| 273 | inode->i_nlink = 0; | ||
| 274 | fuse_invalidate_attr(inode); | ||
| 275 | fuse_invalidate_attr(dir); | ||
| 276 | } else if (err == -EINTR) | ||
| 277 | fuse_invalidate_entry(entry); | ||
| 278 | return err; | ||
| 279 | } | ||
| 280 | |||
| 281 | static int fuse_rmdir(struct inode *dir, struct dentry *entry) | ||
| 282 | { | ||
| 283 | int err; | ||
| 284 | struct fuse_conn *fc = get_fuse_conn(dir); | ||
| 285 | struct fuse_req *req = fuse_get_request(fc); | ||
| 286 | if (!req) | ||
| 287 | return -EINTR; | ||
| 288 | |||
| 289 | req->in.h.opcode = FUSE_RMDIR; | ||
| 290 | req->in.h.nodeid = get_node_id(dir); | ||
| 291 | req->inode = dir; | ||
| 292 | req->in.numargs = 1; | ||
| 293 | req->in.args[0].size = entry->d_name.len + 1; | ||
| 294 | req->in.args[0].value = entry->d_name.name; | ||
| 295 | request_send(fc, req); | ||
| 296 | err = req->out.h.error; | ||
| 297 | fuse_put_request(fc, req); | ||
| 298 | if (!err) { | ||
| 299 | entry->d_inode->i_nlink = 0; | ||
| 300 | fuse_invalidate_attr(dir); | ||
| 301 | } else if (err == -EINTR) | ||
| 302 | fuse_invalidate_entry(entry); | ||
| 303 | return err; | ||
| 304 | } | ||
| 305 | |||
| 306 | static int fuse_rename(struct inode *olddir, struct dentry *oldent, | ||
| 307 | struct inode *newdir, struct dentry *newent) | ||
| 308 | { | ||
| 309 | int err; | ||
| 310 | struct fuse_rename_in inarg; | ||
| 311 | struct fuse_conn *fc = get_fuse_conn(olddir); | ||
| 312 | struct fuse_req *req = fuse_get_request(fc); | ||
| 313 | if (!req) | ||
| 314 | return -EINTR; | ||
| 315 | |||
| 316 | memset(&inarg, 0, sizeof(inarg)); | ||
| 317 | inarg.newdir = get_node_id(newdir); | ||
| 318 | req->in.h.opcode = FUSE_RENAME; | ||
| 319 | req->in.h.nodeid = get_node_id(olddir); | ||
| 320 | req->inode = olddir; | ||
| 321 | req->inode2 = newdir; | ||
| 322 | req->in.numargs = 3; | ||
| 323 | req->in.args[0].size = sizeof(inarg); | ||
| 324 | req->in.args[0].value = &inarg; | ||
| 325 | req->in.args[1].size = oldent->d_name.len + 1; | ||
| 326 | req->in.args[1].value = oldent->d_name.name; | ||
| 327 | req->in.args[2].size = newent->d_name.len + 1; | ||
| 328 | req->in.args[2].value = newent->d_name.name; | ||
| 329 | request_send(fc, req); | ||
| 330 | err = req->out.h.error; | ||
| 331 | fuse_put_request(fc, req); | ||
| 332 | if (!err) { | ||
| 333 | fuse_invalidate_attr(olddir); | ||
| 334 | if (olddir != newdir) | ||
| 335 | fuse_invalidate_attr(newdir); | ||
| 336 | } else if (err == -EINTR) { | ||
| 337 | /* If request was interrupted, DEITY only knows if the | ||
| 338 | rename actually took place. If the invalidation | ||
| 339 | fails (e.g. some process has CWD under the renamed | ||
| 340 | directory), then there can be inconsistency between | ||
| 341 | the dcache and the real filesystem. Tough luck. */ | ||
| 342 | fuse_invalidate_entry(oldent); | ||
| 343 | if (newent->d_inode) | ||
| 344 | fuse_invalidate_entry(newent); | ||
| 345 | } | ||
| 346 | |||
| 347 | return err; | ||
| 348 | } | ||
| 349 | |||
| 350 | static int fuse_link(struct dentry *entry, struct inode *newdir, | ||
| 351 | struct dentry *newent) | ||
| 352 | { | ||
| 353 | int err; | ||
| 354 | struct fuse_link_in inarg; | ||
| 355 | struct inode *inode = entry->d_inode; | ||
| 356 | struct fuse_conn *fc = get_fuse_conn(inode); | ||
| 357 | struct fuse_req *req = fuse_get_request(fc); | ||
| 358 | if (!req) | ||
| 359 | return -EINTR; | ||
| 360 | |||
| 361 | memset(&inarg, 0, sizeof(inarg)); | ||
| 362 | inarg.oldnodeid = get_node_id(inode); | ||
| 363 | req->in.h.opcode = FUSE_LINK; | ||
| 364 | req->inode2 = inode; | ||
| 365 | req->in.numargs = 2; | ||
| 366 | req->in.args[0].size = sizeof(inarg); | ||
| 367 | req->in.args[0].value = &inarg; | ||
| 368 | req->in.args[1].size = newent->d_name.len + 1; | ||
| 369 | req->in.args[1].value = newent->d_name.name; | ||
| 370 | err = create_new_entry(fc, req, newdir, newent, inode->i_mode); | ||
| 371 | /* Contrary to "normal" filesystems it can happen that link | ||
| 372 | makes two "logical" inodes point to the same "physical" | ||
| 373 | inode. We invalidate the attributes of the old one, so it | ||
| 374 | will reflect changes in the backing inode (link count, | ||
| 375 | etc.) | ||
| 376 | */ | ||
| 377 | if (!err || err == -EINTR) | ||
| 378 | fuse_invalidate_attr(inode); | ||
| 379 | return err; | ||
| 380 | } | ||
| 381 | |||
| 382 | int fuse_do_getattr(struct inode *inode) | ||
| 383 | { | ||
| 384 | int err; | ||
| 385 | struct fuse_attr_out arg; | ||
| 386 | struct fuse_conn *fc = get_fuse_conn(inode); | ||
| 387 | struct fuse_req *req = fuse_get_request(fc); | ||
| 388 | if (!req) | ||
| 389 | return -EINTR; | ||
| 390 | |||
| 391 | req->in.h.opcode = FUSE_GETATTR; | ||
| 392 | req->in.h.nodeid = get_node_id(inode); | ||
| 393 | req->inode = inode; | ||
| 394 | req->out.numargs = 1; | ||
| 395 | req->out.args[0].size = sizeof(arg); | ||
| 396 | req->out.args[0].value = &arg; | ||
| 397 | request_send(fc, req); | ||
| 398 | err = req->out.h.error; | ||
| 399 | fuse_put_request(fc, req); | ||
| 400 | if (!err) { | ||
| 401 | if ((inode->i_mode ^ arg.attr.mode) & S_IFMT) { | ||
| 402 | make_bad_inode(inode); | ||
| 403 | err = -EIO; | ||
| 404 | } else { | ||
| 405 | struct fuse_inode *fi = get_fuse_inode(inode); | ||
| 406 | fuse_change_attributes(inode, &arg.attr); | ||
| 407 | fi->i_time = time_to_jiffies(arg.attr_valid, | ||
| 408 | arg.attr_valid_nsec); | ||
| 409 | } | ||
| 410 | } | ||
| 411 | return err; | ||
| 412 | } | ||
| 413 | |||
| 414 | /* | ||
| 415 | * Calling into a user-controlled filesystem gives the filesystem | ||
| 416 | * daemon ptrace-like capabilities over the requester process. This | ||
| 417 | * means, that the filesystem daemon is able to record the exact | ||
| 418 | * filesystem operations performed, and can also control the behavior | ||
| 419 | * of the requester process in otherwise impossible ways. For example | ||
| 420 | * it can delay the operation for arbitrary length of time allowing | ||
| 421 | * DoS against the requester. | ||
| 422 | * | ||
| 423 | * For this reason only those processes can call into the filesystem, | ||
| 424 | * for which the owner of the mount has ptrace privilege. This | ||
| 425 | * excludes processes started by other users, suid or sgid processes. | ||
| 426 | */ | ||
| 427 | static int fuse_allow_task(struct fuse_conn *fc, struct task_struct *task) | ||
| 428 | { | ||
| 429 | if (fc->flags & FUSE_ALLOW_OTHER) | ||
| 430 | return 1; | ||
| 431 | |||
| 432 | if (task->euid == fc->user_id && | ||
| 433 | task->suid == fc->user_id && | ||
| 434 | task->uid == fc->user_id && | ||
| 435 | task->egid == fc->group_id && | ||
| 436 | task->sgid == fc->group_id && | ||
| 437 | task->gid == fc->group_id) | ||
| 438 | return 1; | ||
| 439 | |||
| 440 | return 0; | ||
| 441 | } | ||
| 442 | |||
| 443 | static int fuse_revalidate(struct dentry *entry) | ||
| 444 | { | ||
| 445 | struct inode *inode = entry->d_inode; | ||
| 446 | struct fuse_inode *fi = get_fuse_inode(inode); | ||
| 447 | struct fuse_conn *fc = get_fuse_conn(inode); | ||
| 448 | |||
| 449 | if (!fuse_allow_task(fc, current)) | ||
| 450 | return -EACCES; | ||
| 451 | if (get_node_id(inode) != FUSE_ROOT_ID && | ||
| 452 | time_before_eq(jiffies, fi->i_time)) | ||
| 453 | return 0; | ||
| 454 | |||
| 455 | return fuse_do_getattr(inode); | ||
| 456 | } | ||
| 457 | |||
| 458 | static int fuse_permission(struct inode *inode, int mask, struct nameidata *nd) | ||
| 459 | { | ||
| 460 | struct fuse_conn *fc = get_fuse_conn(inode); | ||
| 461 | |||
| 462 | if (!fuse_allow_task(fc, current)) | ||
| 463 | return -EACCES; | ||
| 464 | else if (fc->flags & FUSE_DEFAULT_PERMISSIONS) { | ||
| 465 | int err = generic_permission(inode, mask, NULL); | ||
| 466 | |||
| 467 | /* If permission is denied, try to refresh file | ||
| 468 | attributes. This is also needed, because the root | ||
| 469 | node will at first have no permissions */ | ||
| 470 | if (err == -EACCES) { | ||
| 471 | err = fuse_do_getattr(inode); | ||
| 472 | if (!err) | ||
| 473 | err = generic_permission(inode, mask, NULL); | ||
| 474 | } | ||
| 475 | |||
| 476 | /* FIXME: Need some mechanism to revoke permissions: | ||
| 477 | currently if the filesystem suddenly changes the | ||
| 478 | file mode, we will not be informed about it, and | ||
| 479 | continue to allow access to the file/directory. | ||
| 480 | |||
| 481 | This is actually not so grave, since the user can | ||
| 482 | simply keep access to the file/directory anyway by | ||
| 483 | keeping it open... */ | ||
| 484 | |||
| 485 | return err; | ||
| 486 | } else { | ||
| 487 | int mode = inode->i_mode; | ||
| 488 | if ((mask & MAY_WRITE) && IS_RDONLY(inode) && | ||
| 489 | (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode))) | ||
| 490 | return -EROFS; | ||
| 491 | if ((mask & MAY_EXEC) && !S_ISDIR(mode) && !(mode & S_IXUGO)) | ||
| 492 | return -EACCES; | ||
| 493 | return 0; | ||
| 494 | } | ||
| 495 | } | ||
| 496 | |||
| 497 | static int parse_dirfile(char *buf, size_t nbytes, struct file *file, | ||
| 498 | void *dstbuf, filldir_t filldir) | ||
| 499 | { | ||
| 500 | while (nbytes >= FUSE_NAME_OFFSET) { | ||
| 501 | struct fuse_dirent *dirent = (struct fuse_dirent *) buf; | ||
| 502 | size_t reclen = FUSE_DIRENT_SIZE(dirent); | ||
| 503 | int over; | ||
| 504 | if (!dirent->namelen || dirent->namelen > FUSE_NAME_MAX) | ||
| 505 | return -EIO; | ||
| 506 | if (reclen > nbytes) | ||
| 507 | break; | ||
| 508 | |||
| 509 | over = filldir(dstbuf, dirent->name, dirent->namelen, | ||
| 510 | file->f_pos, dirent->ino, dirent->type); | ||
| 511 | if (over) | ||
| 512 | break; | ||
| 513 | |||
| 514 | buf += reclen; | ||
| 515 | nbytes -= reclen; | ||
| 516 | file->f_pos = dirent->off; | ||
| 517 | } | ||
| 518 | |||
| 519 | return 0; | ||
| 520 | } | ||
| 521 | |||
| 522 | static inline size_t fuse_send_readdir(struct fuse_req *req, struct file *file, | ||
| 523 | struct inode *inode, loff_t pos, | ||
| 524 | size_t count) | ||
| 525 | { | ||
| 526 | return fuse_send_read_common(req, file, inode, pos, count, 1); | ||
| 527 | } | ||
| 528 | |||
| 529 | static int fuse_readdir(struct file *file, void *dstbuf, filldir_t filldir) | ||
| 530 | { | ||
| 531 | int err; | ||
| 532 | size_t nbytes; | ||
| 533 | struct page *page; | ||
| 534 | struct inode *inode = file->f_dentry->d_inode; | ||
| 535 | struct fuse_conn *fc = get_fuse_conn(inode); | ||
| 536 | struct fuse_req *req = fuse_get_request(fc); | ||
| 537 | if (!req) | ||
| 538 | return -EINTR; | ||
| 539 | |||
| 540 | page = alloc_page(GFP_KERNEL); | ||
| 541 | if (!page) { | ||
| 542 | fuse_put_request(fc, req); | ||
| 543 | return -ENOMEM; | ||
| 544 | } | ||
| 545 | req->num_pages = 1; | ||
| 546 | req->pages[0] = page; | ||
| 547 | nbytes = fuse_send_readdir(req, file, inode, file->f_pos, PAGE_SIZE); | ||
| 548 | err = req->out.h.error; | ||
| 549 | fuse_put_request(fc, req); | ||
| 550 | if (!err) | ||
| 551 | err = parse_dirfile(page_address(page), nbytes, file, dstbuf, | ||
| 552 | filldir); | ||
| 553 | |||
| 554 | __free_page(page); | ||
| 555 | fuse_invalidate_attr(inode); /* atime changed */ | ||
| 556 | return err; | ||
| 557 | } | ||
| 558 | |||
| 559 | static char *read_link(struct dentry *dentry) | ||
| 560 | { | ||
| 561 | struct inode *inode = dentry->d_inode; | ||
| 562 | struct fuse_conn *fc = get_fuse_conn(inode); | ||
| 563 | struct fuse_req *req = fuse_get_request(fc); | ||
| 564 | char *link; | ||
| 565 | |||
| 566 | if (!req) | ||
| 567 | return ERR_PTR(-EINTR); | ||
| 568 | |||
| 569 | link = (char *) __get_free_page(GFP_KERNEL); | ||
| 570 | if (!link) { | ||
| 571 | link = ERR_PTR(-ENOMEM); | ||
| 572 | goto out; | ||
| 573 | } | ||
| 574 | req->in.h.opcode = FUSE_READLINK; | ||
| 575 | req->in.h.nodeid = get_node_id(inode); | ||
| 576 | req->inode = inode; | ||
| 577 | req->out.argvar = 1; | ||
| 578 | req->out.numargs = 1; | ||
| 579 | req->out.args[0].size = PAGE_SIZE - 1; | ||
| 580 | req->out.args[0].value = link; | ||
| 581 | request_send(fc, req); | ||
| 582 | if (req->out.h.error) { | ||
| 583 | free_page((unsigned long) link); | ||
| 584 | link = ERR_PTR(req->out.h.error); | ||
| 585 | } else | ||
| 586 | link[req->out.args[0].size] = '\0'; | ||
| 587 | out: | ||
| 588 | fuse_put_request(fc, req); | ||
| 589 | fuse_invalidate_attr(inode); /* atime changed */ | ||
| 590 | return link; | ||
| 591 | } | ||
| 592 | |||
| 593 | static void free_link(char *link) | ||
| 594 | { | ||
| 595 | if (!IS_ERR(link)) | ||
| 596 | free_page((unsigned long) link); | ||
| 597 | } | ||
| 598 | |||
| 599 | static void *fuse_follow_link(struct dentry *dentry, struct nameidata *nd) | ||
| 600 | { | ||
| 601 | nd_set_link(nd, read_link(dentry)); | ||
| 602 | return NULL; | ||
| 603 | } | ||
| 604 | |||
| 605 | static void fuse_put_link(struct dentry *dentry, struct nameidata *nd, void *c) | ||
| 606 | { | ||
| 607 | free_link(nd_get_link(nd)); | ||
| 608 | } | ||
| 609 | |||
| 610 | static int fuse_dir_open(struct inode *inode, struct file *file) | ||
| 611 | { | ||
| 612 | return fuse_open_common(inode, file, 1); | ||
| 613 | } | ||
| 614 | |||
| 615 | static int fuse_dir_release(struct inode *inode, struct file *file) | ||
| 616 | { | ||
| 617 | return fuse_release_common(inode, file, 1); | ||
| 618 | } | ||
| 619 | |||
| 620 | static int fuse_dir_fsync(struct file *file, struct dentry *de, int datasync) | ||
| 621 | { | ||
| 622 | /* nfsd can call this with no file */ | ||
| 623 | return file ? fuse_fsync_common(file, de, datasync, 1) : 0; | ||
| 624 | } | ||
| 625 | |||
| 626 | static unsigned iattr_to_fattr(struct iattr *iattr, struct fuse_attr *fattr) | ||
| 627 | { | ||
| 628 | unsigned ivalid = iattr->ia_valid; | ||
| 629 | unsigned fvalid = 0; | ||
| 630 | |||
| 631 | memset(fattr, 0, sizeof(*fattr)); | ||
| 632 | |||
| 633 | if (ivalid & ATTR_MODE) | ||
| 634 | fvalid |= FATTR_MODE, fattr->mode = iattr->ia_mode; | ||
| 635 | if (ivalid & ATTR_UID) | ||
| 636 | fvalid |= FATTR_UID, fattr->uid = iattr->ia_uid; | ||
| 637 | if (ivalid & ATTR_GID) | ||
| 638 | fvalid |= FATTR_GID, fattr->gid = iattr->ia_gid; | ||
| 639 | if (ivalid & ATTR_SIZE) | ||
| 640 | fvalid |= FATTR_SIZE, fattr->size = iattr->ia_size; | ||
| 641 | /* You can only _set_ these together (they may change by themselves) */ | ||
| 642 | if ((ivalid & (ATTR_ATIME | ATTR_MTIME)) == (ATTR_ATIME | ATTR_MTIME)) { | ||
| 643 | fvalid |= FATTR_ATIME | FATTR_MTIME; | ||
| 644 | fattr->atime = iattr->ia_atime.tv_sec; | ||
| 645 | fattr->mtime = iattr->ia_mtime.tv_sec; | ||
| 646 | } | ||
| 647 | |||
| 648 | return fvalid; | ||
| 649 | } | ||
| 650 | |||
| 651 | static int fuse_setattr(struct dentry *entry, struct iattr *attr) | ||
| 652 | { | ||
| 653 | struct inode *inode = entry->d_inode; | ||
| 654 | struct fuse_conn *fc = get_fuse_conn(inode); | ||
| 655 | struct fuse_inode *fi = get_fuse_inode(inode); | ||
| 656 | struct fuse_req *req; | ||
| 657 | struct fuse_setattr_in inarg; | ||
| 658 | struct fuse_attr_out outarg; | ||
| 659 | int err; | ||
| 660 | int is_truncate = 0; | ||
| 661 | |||
| 662 | if (fc->flags & FUSE_DEFAULT_PERMISSIONS) { | ||
| 663 | err = inode_change_ok(inode, attr); | ||
| 664 | if (err) | ||
| 665 | return err; | ||
| 666 | } | ||
| 667 | |||
| 668 | if (attr->ia_valid & ATTR_SIZE) { | ||
| 669 | unsigned long limit; | ||
| 670 | is_truncate = 1; | ||
| 671 | limit = current->signal->rlim[RLIMIT_FSIZE].rlim_cur; | ||
| 672 | if (limit != RLIM_INFINITY && attr->ia_size > (loff_t) limit) { | ||
| 673 | send_sig(SIGXFSZ, current, 0); | ||
| 674 | return -EFBIG; | ||
| 675 | } | ||
| 676 | } | ||
| 677 | |||
| 678 | req = fuse_get_request(fc); | ||
| 679 | if (!req) | ||
| 680 | return -EINTR; | ||
| 681 | |||
| 682 | memset(&inarg, 0, sizeof(inarg)); | ||
| 683 | inarg.valid = iattr_to_fattr(attr, &inarg.attr); | ||
| 684 | req->in.h.opcode = FUSE_SETATTR; | ||
| 685 | req->in.h.nodeid = get_node_id(inode); | ||
| 686 | req->inode = inode; | ||
| 687 | req->in.numargs = 1; | ||
| 688 | req->in.args[0].size = sizeof(inarg); | ||
| 689 | req->in.args[0].value = &inarg; | ||
| 690 | req->out.numargs = 1; | ||
| 691 | req->out.args[0].size = sizeof(outarg); | ||
| 692 | req->out.args[0].value = &outarg; | ||
| 693 | request_send(fc, req); | ||
| 694 | err = req->out.h.error; | ||
| 695 | fuse_put_request(fc, req); | ||
| 696 | if (!err) { | ||
| 697 | if ((inode->i_mode ^ outarg.attr.mode) & S_IFMT) { | ||
| 698 | make_bad_inode(inode); | ||
| 699 | err = -EIO; | ||
| 700 | } else { | ||
| 701 | if (is_truncate) { | ||
| 702 | loff_t origsize = i_size_read(inode); | ||
| 703 | i_size_write(inode, outarg.attr.size); | ||
| 704 | if (origsize > outarg.attr.size) | ||
| 705 | vmtruncate(inode, outarg.attr.size); | ||
| 706 | } | ||
| 707 | fuse_change_attributes(inode, &outarg.attr); | ||
| 708 | fi->i_time = time_to_jiffies(outarg.attr_valid, | ||
| 709 | outarg.attr_valid_nsec); | ||
| 710 | } | ||
| 711 | } else if (err == -EINTR) | ||
| 712 | fuse_invalidate_attr(inode); | ||
| 713 | |||
| 714 | return err; | ||
| 715 | } | ||
| 716 | |||
| 717 | static int fuse_getattr(struct vfsmount *mnt, struct dentry *entry, | ||
| 718 | struct kstat *stat) | ||
| 719 | { | ||
| 720 | struct inode *inode = entry->d_inode; | ||
| 721 | int err = fuse_revalidate(entry); | ||
| 722 | if (!err) | ||
| 723 | generic_fillattr(inode, stat); | ||
| 724 | |||
| 725 | return err; | ||
| 726 | } | ||
| 727 | |||
| 728 | static struct dentry *fuse_lookup(struct inode *dir, struct dentry *entry, | ||
| 729 | struct nameidata *nd) | ||
| 730 | { | ||
| 731 | struct inode *inode; | ||
| 732 | int err = fuse_lookup_iget(dir, entry, &inode); | ||
| 733 | if (err) | ||
| 734 | return ERR_PTR(err); | ||
| 735 | if (inode && S_ISDIR(inode->i_mode)) { | ||
| 736 | /* Don't allow creating an alias to a directory */ | ||
| 737 | struct dentry *alias = d_find_alias(inode); | ||
| 738 | if (alias && !(alias->d_flags & DCACHE_DISCONNECTED)) { | ||
| 739 | dput(alias); | ||
| 740 | iput(inode); | ||
| 741 | return ERR_PTR(-EIO); | ||
| 742 | } | ||
| 743 | } | ||
| 744 | return d_splice_alias(inode, entry); | ||
| 745 | } | ||
| 746 | |||
| 747 | static int fuse_setxattr(struct dentry *entry, const char *name, | ||
| 748 | const void *value, size_t size, int flags) | ||
| 749 | { | ||
| 750 | struct inode *inode = entry->d_inode; | ||
| 751 | struct fuse_conn *fc = get_fuse_conn(inode); | ||
| 752 | struct fuse_req *req; | ||
| 753 | struct fuse_setxattr_in inarg; | ||
| 754 | int err; | ||
| 755 | |||
| 756 | if (size > FUSE_XATTR_SIZE_MAX) | ||
| 757 | return -E2BIG; | ||
| 758 | |||
| 759 | if (fc->no_setxattr) | ||
| 760 | return -EOPNOTSUPP; | ||
| 761 | |||
| 762 | req = fuse_get_request(fc); | ||
| 763 | if (!req) | ||
| 764 | return -EINTR; | ||
| 765 | |||
| 766 | memset(&inarg, 0, sizeof(inarg)); | ||
| 767 | inarg.size = size; | ||
| 768 | inarg.flags = flags; | ||
| 769 | req->in.h.opcode = FUSE_SETXATTR; | ||
| 770 | req->in.h.nodeid = get_node_id(inode); | ||
| 771 | req->inode = inode; | ||
| 772 | req->in.numargs = 3; | ||
| 773 | req->in.args[0].size = sizeof(inarg); | ||
| 774 | req->in.args[0].value = &inarg; | ||
| 775 | req->in.args[1].size = strlen(name) + 1; | ||
| 776 | req->in.args[1].value = name; | ||
| 777 | req->in.args[2].size = size; | ||
| 778 | req->in.args[2].value = value; | ||
| 779 | request_send(fc, req); | ||
| 780 | err = req->out.h.error; | ||
| 781 | fuse_put_request(fc, req); | ||
| 782 | if (err == -ENOSYS) { | ||
| 783 | fc->no_setxattr = 1; | ||
| 784 | err = -EOPNOTSUPP; | ||
| 785 | } | ||
| 786 | return err; | ||
| 787 | } | ||
| 788 | |||
| 789 | static ssize_t fuse_getxattr(struct dentry *entry, const char *name, | ||
| 790 | void *value, size_t size) | ||
| 791 | { | ||
| 792 | struct inode *inode = entry->d_inode; | ||
| 793 | struct fuse_conn *fc = get_fuse_conn(inode); | ||
| 794 | struct fuse_req *req; | ||
| 795 | struct fuse_getxattr_in inarg; | ||
| 796 | struct fuse_getxattr_out outarg; | ||
| 797 | ssize_t ret; | ||
| 798 | |||
| 799 | if (fc->no_getxattr) | ||
| 800 | return -EOPNOTSUPP; | ||
| 801 | |||
| 802 | req = fuse_get_request(fc); | ||
| 803 | if (!req) | ||
| 804 | return -EINTR; | ||
| 805 | |||
| 806 | memset(&inarg, 0, sizeof(inarg)); | ||
| 807 | inarg.size = size; | ||
| 808 | req->in.h.opcode = FUSE_GETXATTR; | ||
| 809 | req->in.h.nodeid = get_node_id(inode); | ||
| 810 | req->inode = inode; | ||
| 811 | req->in.numargs = 2; | ||
| 812 | req->in.args[0].size = sizeof(inarg); | ||
| 813 | req->in.args[0].value = &inarg; | ||
| 814 | req->in.args[1].size = strlen(name) + 1; | ||
| 815 | req->in.args[1].value = name; | ||
| 816 | /* This is really two different operations rolled into one */ | ||
| 817 | req->out.numargs = 1; | ||
| 818 | if (size) { | ||
| 819 | req->out.argvar = 1; | ||
| 820 | req->out.args[0].size = size; | ||
| 821 | req->out.args[0].value = value; | ||
| 822 | } else { | ||
| 823 | req->out.args[0].size = sizeof(outarg); | ||
| 824 | req->out.args[0].value = &outarg; | ||
| 825 | } | ||
| 826 | request_send(fc, req); | ||
| 827 | ret = req->out.h.error; | ||
| 828 | if (!ret) | ||
| 829 | ret = size ? req->out.args[0].size : outarg.size; | ||
| 830 | else { | ||
| 831 | if (ret == -ENOSYS) { | ||
| 832 | fc->no_getxattr = 1; | ||
| 833 | ret = -EOPNOTSUPP; | ||
| 834 | } | ||
| 835 | } | ||
| 836 | fuse_put_request(fc, req); | ||
| 837 | return ret; | ||
| 838 | } | ||
| 839 | |||
| 840 | static ssize_t fuse_listxattr(struct dentry *entry, char *list, size_t size) | ||
| 841 | { | ||
| 842 | struct inode *inode = entry->d_inode; | ||
| 843 | struct fuse_conn *fc = get_fuse_conn(inode); | ||
| 844 | struct fuse_req *req; | ||
| 845 | struct fuse_getxattr_in inarg; | ||
| 846 | struct fuse_getxattr_out outarg; | ||
| 847 | ssize_t ret; | ||
| 848 | |||
| 849 | if (fc->no_listxattr) | ||
| 850 | return -EOPNOTSUPP; | ||
| 851 | |||
| 852 | req = fuse_get_request(fc); | ||
| 853 | if (!req) | ||
| 854 | return -EINTR; | ||
| 855 | |||
| 856 | memset(&inarg, 0, sizeof(inarg)); | ||
| 857 | inarg.size = size; | ||
| 858 | req->in.h.opcode = FUSE_LISTXATTR; | ||
| 859 | req->in.h.nodeid = get_node_id(inode); | ||
| 860 | req->inode = inode; | ||
| 861 | req->in.numargs = 1; | ||
| 862 | req->in.args[0].size = sizeof(inarg); | ||
| 863 | req->in.args[0].value = &inarg; | ||
| 864 | /* This is really two different operations rolled into one */ | ||
| 865 | req->out.numargs = 1; | ||
| 866 | if (size) { | ||
| 867 | req->out.argvar = 1; | ||
| 868 | req->out.args[0].size = size; | ||
| 869 | req->out.args[0].value = list; | ||
| 870 | } else { | ||
| 871 | req->out.args[0].size = sizeof(outarg); | ||
| 872 | req->out.args[0].value = &outarg; | ||
| 873 | } | ||
| 874 | request_send(fc, req); | ||
| 875 | ret = req->out.h.error; | ||
| 876 | if (!ret) | ||
| 877 | ret = size ? req->out.args[0].size : outarg.size; | ||
| 878 | else { | ||
| 879 | if (ret == -ENOSYS) { | ||
| 880 | fc->no_listxattr = 1; | ||
| 881 | ret = -EOPNOTSUPP; | ||
| 882 | } | ||
| 883 | } | ||
| 884 | fuse_put_request(fc, req); | ||
| 885 | return ret; | ||
| 886 | } | ||
| 887 | |||
| 888 | static int fuse_removexattr(struct dentry *entry, const char *name) | ||
| 889 | { | ||
| 890 | struct inode *inode = entry->d_inode; | ||
| 891 | struct fuse_conn *fc = get_fuse_conn(inode); | ||
| 892 | struct fuse_req *req; | ||
| 893 | int err; | ||
| 894 | |||
| 895 | if (fc->no_removexattr) | ||
| 896 | return -EOPNOTSUPP; | ||
| 897 | |||
| 898 | req = fuse_get_request(fc); | ||
| 899 | if (!req) | ||
| 900 | return -EINTR; | ||
| 901 | |||
| 902 | req->in.h.opcode = FUSE_REMOVEXATTR; | ||
| 903 | req->in.h.nodeid = get_node_id(inode); | ||
| 904 | req->inode = inode; | ||
| 905 | req->in.numargs = 1; | ||
| 906 | req->in.args[0].size = strlen(name) + 1; | ||
| 907 | req->in.args[0].value = name; | ||
| 908 | request_send(fc, req); | ||
| 909 | err = req->out.h.error; | ||
| 910 | fuse_put_request(fc, req); | ||
| 911 | if (err == -ENOSYS) { | ||
| 912 | fc->no_removexattr = 1; | ||
| 913 | err = -EOPNOTSUPP; | ||
| 914 | } | ||
| 915 | return err; | ||
| 916 | } | ||
| 917 | |||
| 918 | static struct inode_operations fuse_dir_inode_operations = { | ||
| 919 | .lookup = fuse_lookup, | ||
| 920 | .mkdir = fuse_mkdir, | ||
| 921 | .symlink = fuse_symlink, | ||
| 922 | .unlink = fuse_unlink, | ||
| 923 | .rmdir = fuse_rmdir, | ||
| 924 | .rename = fuse_rename, | ||
| 925 | .link = fuse_link, | ||
| 926 | .setattr = fuse_setattr, | ||
| 927 | .create = fuse_create, | ||
| 928 | .mknod = fuse_mknod, | ||
| 929 | .permission = fuse_permission, | ||
| 930 | .getattr = fuse_getattr, | ||
| 931 | .setxattr = fuse_setxattr, | ||
| 932 | .getxattr = fuse_getxattr, | ||
| 933 | .listxattr = fuse_listxattr, | ||
| 934 | .removexattr = fuse_removexattr, | ||
| 935 | }; | ||
| 936 | |||
| 937 | static struct file_operations fuse_dir_operations = { | ||
| 938 | .llseek = generic_file_llseek, | ||
| 939 | .read = generic_read_dir, | ||
| 940 | .readdir = fuse_readdir, | ||
| 941 | .open = fuse_dir_open, | ||
| 942 | .release = fuse_dir_release, | ||
| 943 | .fsync = fuse_dir_fsync, | ||
| 944 | }; | ||
| 945 | |||
| 946 | static struct inode_operations fuse_common_inode_operations = { | ||
| 947 | .setattr = fuse_setattr, | ||
| 948 | .permission = fuse_permission, | ||
| 949 | .getattr = fuse_getattr, | ||
| 950 | .setxattr = fuse_setxattr, | ||
| 951 | .getxattr = fuse_getxattr, | ||
| 952 | .listxattr = fuse_listxattr, | ||
| 953 | .removexattr = fuse_removexattr, | ||
| 954 | }; | ||
| 955 | |||
| 956 | static struct inode_operations fuse_symlink_inode_operations = { | ||
| 957 | .setattr = fuse_setattr, | ||
| 958 | .follow_link = fuse_follow_link, | ||
| 959 | .put_link = fuse_put_link, | ||
| 960 | .readlink = generic_readlink, | ||
| 961 | .getattr = fuse_getattr, | ||
| 962 | .setxattr = fuse_setxattr, | ||
| 963 | .getxattr = fuse_getxattr, | ||
| 964 | .listxattr = fuse_listxattr, | ||
| 965 | .removexattr = fuse_removexattr, | ||
| 966 | }; | ||
| 967 | |||
| 968 | void fuse_init_common(struct inode *inode) | ||
| 969 | { | ||
| 970 | inode->i_op = &fuse_common_inode_operations; | ||
| 971 | } | ||
| 972 | |||
| 973 | void fuse_init_dir(struct inode *inode) | ||
| 974 | { | ||
| 975 | inode->i_op = &fuse_dir_inode_operations; | ||
| 976 | inode->i_fop = &fuse_dir_operations; | ||
| 977 | } | ||
| 978 | |||
| 979 | void fuse_init_symlink(struct inode *inode) | ||
| 980 | { | ||
| 981 | inode->i_op = &fuse_symlink_inode_operations; | ||
| 982 | } | ||
