Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | |
| 2 | /* |
| 3 | * Directory operations for Coda filesystem |
| 4 | * Original version: (C) 1996 P. Braam and M. Callahan |
| 5 | * Rewritten for Linux 2.1. (C) 1997 Carnegie Mellon University |
| 6 | * |
| 7 | * Carnegie Mellon encourages users to contribute improvements to |
| 8 | * the Coda project. Contact Peter Braam (coda@cs.cmu.edu). |
| 9 | */ |
| 10 | |
| 11 | #include <linux/types.h> |
| 12 | #include <linux/kernel.h> |
| 13 | #include <linux/time.h> |
| 14 | #include <linux/fs.h> |
| 15 | #include <linux/file.h> |
| 16 | #include <linux/stat.h> |
| 17 | #include <linux/errno.h> |
| 18 | #include <linux/string.h> |
| 19 | #include <linux/smp_lock.h> |
| 20 | |
| 21 | #include <asm/uaccess.h> |
| 22 | |
| 23 | #include <linux/coda.h> |
| 24 | #include <linux/coda_linux.h> |
| 25 | #include <linux/coda_psdev.h> |
| 26 | #include <linux/coda_fs_i.h> |
| 27 | #include <linux/coda_cache.h> |
| 28 | #include <linux/coda_proc.h> |
| 29 | |
| 30 | /* dir inode-ops */ |
| 31 | static int coda_create(struct inode *dir, struct dentry *new, int mode, struct nameidata *nd); |
| 32 | static struct dentry *coda_lookup(struct inode *dir, struct dentry *target, struct nameidata *nd); |
| 33 | static int coda_link(struct dentry *old_dentry, struct inode *dir_inode, |
| 34 | struct dentry *entry); |
| 35 | static int coda_unlink(struct inode *dir_inode, struct dentry *entry); |
| 36 | static int coda_symlink(struct inode *dir_inode, struct dentry *entry, |
| 37 | const char *symname); |
| 38 | static int coda_mkdir(struct inode *dir_inode, struct dentry *entry, int mode); |
| 39 | static int coda_rmdir(struct inode *dir_inode, struct dentry *entry); |
| 40 | static int coda_rename(struct inode *old_inode, struct dentry *old_dentry, |
| 41 | struct inode *new_inode, struct dentry *new_dentry); |
| 42 | |
| 43 | /* dir file-ops */ |
| 44 | static int coda_readdir(struct file *file, void *dirent, filldir_t filldir); |
| 45 | |
| 46 | /* dentry ops */ |
| 47 | static int coda_dentry_revalidate(struct dentry *de, struct nameidata *nd); |
| 48 | static int coda_dentry_delete(struct dentry *); |
| 49 | |
| 50 | /* support routines */ |
| 51 | static int coda_venus_readdir(struct file *filp, filldir_t filldir, |
| 52 | void *dirent, struct dentry *dir); |
| 53 | int coda_fsync(struct file *, struct dentry *dentry, int datasync); |
| 54 | |
| 55 | /* same as fs/bad_inode.c */ |
| 56 | static int coda_return_EIO(void) |
| 57 | { |
| 58 | return -EIO; |
| 59 | } |
| 60 | #define CODA_EIO_ERROR ((void *) (coda_return_EIO)) |
| 61 | |
| 62 | static struct dentry_operations coda_dentry_operations = |
| 63 | { |
| 64 | .d_revalidate = coda_dentry_revalidate, |
| 65 | .d_delete = coda_dentry_delete, |
| 66 | }; |
| 67 | |
| 68 | struct inode_operations coda_dir_inode_operations = |
| 69 | { |
| 70 | .create = coda_create, |
| 71 | .lookup = coda_lookup, |
| 72 | .link = coda_link, |
| 73 | .unlink = coda_unlink, |
| 74 | .symlink = coda_symlink, |
| 75 | .mkdir = coda_mkdir, |
| 76 | .rmdir = coda_rmdir, |
| 77 | .mknod = CODA_EIO_ERROR, |
| 78 | .rename = coda_rename, |
| 79 | .permission = coda_permission, |
| 80 | .getattr = coda_getattr, |
| 81 | .setattr = coda_setattr, |
| 82 | }; |
| 83 | |
| 84 | struct file_operations coda_dir_operations = { |
| 85 | .llseek = generic_file_llseek, |
| 86 | .read = generic_read_dir, |
| 87 | .readdir = coda_readdir, |
| 88 | .open = coda_open, |
| 89 | .flush = coda_flush, |
| 90 | .release = coda_release, |
| 91 | .fsync = coda_fsync, |
| 92 | }; |
| 93 | |
| 94 | |
| 95 | /* inode operations for directories */ |
| 96 | /* access routines: lookup, readlink, permission */ |
| 97 | static struct dentry *coda_lookup(struct inode *dir, struct dentry *entry, struct nameidata *nd) |
| 98 | { |
| 99 | struct inode *res_inode = NULL; |
| 100 | struct CodaFid resfid = { { 0, } }; |
| 101 | int dropme = 0; /* to indicate entry should not be cached */ |
| 102 | int type = 0; |
| 103 | int error = 0; |
| 104 | const char *name = entry->d_name.name; |
| 105 | size_t length = entry->d_name.len; |
| 106 | |
| 107 | if ( length > CODA_MAXNAMLEN ) { |
| 108 | printk("name too long: lookup, %s (%*s)\n", |
| 109 | coda_i2s(dir), (int)length, name); |
| 110 | return ERR_PTR(-ENAMETOOLONG); |
| 111 | } |
| 112 | |
| 113 | lock_kernel(); |
| 114 | /* control object, create inode on the fly */ |
| 115 | if (coda_isroot(dir) && coda_iscontrol(name, length)) { |
| 116 | error = coda_cnode_makectl(&res_inode, dir->i_sb); |
| 117 | dropme = 1; |
| 118 | goto exit; |
| 119 | } |
| 120 | |
| 121 | error = venus_lookup(dir->i_sb, coda_i2f(dir), |
| 122 | (const char *)name, length, &type, &resfid); |
| 123 | |
| 124 | res_inode = NULL; |
| 125 | if (!error) { |
| 126 | if (type & CODA_NOCACHE) { |
| 127 | type &= (~CODA_NOCACHE); |
| 128 | dropme = 1; |
| 129 | } |
| 130 | |
| 131 | error = coda_cnode_make(&res_inode, &resfid, dir->i_sb); |
| 132 | if (error) { |
| 133 | unlock_kernel(); |
| 134 | return ERR_PTR(error); |
| 135 | } |
| 136 | } else if (error != -ENOENT) { |
| 137 | unlock_kernel(); |
| 138 | return ERR_PTR(error); |
| 139 | } |
| 140 | |
| 141 | exit: |
| 142 | entry->d_time = 0; |
| 143 | entry->d_op = &coda_dentry_operations; |
| 144 | d_add(entry, res_inode); |
| 145 | if ( dropme ) { |
| 146 | d_drop(entry); |
| 147 | coda_flag_inode(res_inode, C_VATTR); |
| 148 | } |
| 149 | unlock_kernel(); |
| 150 | return NULL; |
| 151 | } |
| 152 | |
| 153 | |
| 154 | int coda_permission(struct inode *inode, int mask, struct nameidata *nd) |
| 155 | { |
| 156 | int error = 0; |
| 157 | |
| 158 | if (!mask) |
| 159 | return 0; |
| 160 | |
| 161 | lock_kernel(); |
| 162 | |
| 163 | coda_vfs_stat.permission++; |
| 164 | |
| 165 | if (coda_cache_check(inode, mask)) |
| 166 | goto out; |
| 167 | |
| 168 | error = venus_access(inode->i_sb, coda_i2f(inode), mask); |
| 169 | |
| 170 | if (!error) |
| 171 | coda_cache_enter(inode, mask); |
| 172 | |
| 173 | out: |
| 174 | unlock_kernel(); |
| 175 | |
| 176 | return error; |
| 177 | } |
| 178 | |
| 179 | |
| 180 | static inline void coda_dir_changed(struct inode *dir, int link) |
| 181 | { |
| 182 | #ifdef REQUERY_VENUS_FOR_MTIME |
| 183 | /* invalidate the directory cnode's attributes so we refetch the |
| 184 | * attributes from venus next time the inode is referenced */ |
| 185 | coda_flag_inode(dir, C_VATTR); |
| 186 | #else |
| 187 | /* optimistically we can also act as if our nose bleeds. The |
| 188 | * granularity of the mtime is coarse anyways so we might actually be |
| 189 | * right most of the time. Note: we only do this for directories. */ |
| 190 | dir->i_mtime = dir->i_ctime = CURRENT_TIME_SEC; |
| 191 | #endif |
| 192 | if (link) |
| 193 | dir->i_nlink += link; |
| 194 | } |
| 195 | |
| 196 | /* creation routines: create, mknod, mkdir, link, symlink */ |
| 197 | static int coda_create(struct inode *dir, struct dentry *de, int mode, struct nameidata *nd) |
| 198 | { |
| 199 | int error=0; |
| 200 | const char *name=de->d_name.name; |
| 201 | int length=de->d_name.len; |
| 202 | struct inode *inode; |
| 203 | struct CodaFid newfid; |
| 204 | struct coda_vattr attrs; |
| 205 | |
| 206 | lock_kernel(); |
| 207 | coda_vfs_stat.create++; |
| 208 | |
| 209 | if (coda_isroot(dir) && coda_iscontrol(name, length)) { |
| 210 | unlock_kernel(); |
| 211 | return -EPERM; |
| 212 | } |
| 213 | |
| 214 | error = venus_create(dir->i_sb, coda_i2f(dir), name, length, |
| 215 | 0, mode, &newfid, &attrs); |
| 216 | |
| 217 | if ( error ) { |
| 218 | unlock_kernel(); |
| 219 | d_drop(de); |
| 220 | return error; |
| 221 | } |
| 222 | |
| 223 | inode = coda_iget(dir->i_sb, &newfid, &attrs); |
| 224 | if ( IS_ERR(inode) ) { |
| 225 | unlock_kernel(); |
| 226 | d_drop(de); |
| 227 | return PTR_ERR(inode); |
| 228 | } |
| 229 | |
| 230 | /* invalidate the directory cnode's attributes */ |
| 231 | coda_dir_changed(dir, 0); |
| 232 | unlock_kernel(); |
| 233 | d_instantiate(de, inode); |
| 234 | return 0; |
| 235 | } |
| 236 | |
| 237 | static int coda_mkdir(struct inode *dir, struct dentry *de, int mode) |
| 238 | { |
| 239 | struct inode *inode; |
| 240 | struct coda_vattr attrs; |
| 241 | const char *name = de->d_name.name; |
| 242 | int len = de->d_name.len; |
| 243 | int error; |
| 244 | struct CodaFid newfid; |
| 245 | |
| 246 | lock_kernel(); |
| 247 | coda_vfs_stat.mkdir++; |
| 248 | |
| 249 | if (coda_isroot(dir) && coda_iscontrol(name, len)) { |
| 250 | unlock_kernel(); |
| 251 | return -EPERM; |
| 252 | } |
| 253 | |
| 254 | attrs.va_mode = mode; |
| 255 | error = venus_mkdir(dir->i_sb, coda_i2f(dir), |
| 256 | name, len, &newfid, &attrs); |
| 257 | |
| 258 | if ( error ) { |
| 259 | unlock_kernel(); |
| 260 | d_drop(de); |
| 261 | return error; |
| 262 | } |
| 263 | |
| 264 | inode = coda_iget(dir->i_sb, &newfid, &attrs); |
| 265 | if ( IS_ERR(inode) ) { |
| 266 | unlock_kernel(); |
| 267 | d_drop(de); |
| 268 | return PTR_ERR(inode); |
| 269 | } |
| 270 | |
| 271 | /* invalidate the directory cnode's attributes */ |
| 272 | coda_dir_changed(dir, 1); |
| 273 | unlock_kernel(); |
| 274 | d_instantiate(de, inode); |
| 275 | return 0; |
| 276 | } |
| 277 | |
| 278 | /* try to make de an entry in dir_inodde linked to source_de */ |
| 279 | static int coda_link(struct dentry *source_de, struct inode *dir_inode, |
| 280 | struct dentry *de) |
| 281 | { |
| 282 | struct inode *inode = source_de->d_inode; |
| 283 | const char * name = de->d_name.name; |
| 284 | int len = de->d_name.len; |
| 285 | int error; |
| 286 | |
| 287 | lock_kernel(); |
| 288 | coda_vfs_stat.link++; |
| 289 | |
| 290 | if (coda_isroot(dir_inode) && coda_iscontrol(name, len)) { |
| 291 | unlock_kernel(); |
| 292 | return -EPERM; |
| 293 | } |
| 294 | |
| 295 | error = venus_link(dir_inode->i_sb, coda_i2f(inode), |
| 296 | coda_i2f(dir_inode), (const char *)name, len); |
| 297 | |
| 298 | if (error) { |
| 299 | d_drop(de); |
| 300 | goto out; |
| 301 | } |
| 302 | |
| 303 | coda_dir_changed(dir_inode, 0); |
| 304 | atomic_inc(&inode->i_count); |
| 305 | d_instantiate(de, inode); |
| 306 | inode->i_nlink++; |
| 307 | |
| 308 | out: |
| 309 | unlock_kernel(); |
| 310 | return(error); |
| 311 | } |
| 312 | |
| 313 | |
| 314 | static int coda_symlink(struct inode *dir_inode, struct dentry *de, |
| 315 | const char *symname) |
| 316 | { |
| 317 | const char *name = de->d_name.name; |
| 318 | int len = de->d_name.len; |
| 319 | int symlen; |
| 320 | int error=0; |
| 321 | |
| 322 | lock_kernel(); |
| 323 | coda_vfs_stat.symlink++; |
| 324 | |
| 325 | if (coda_isroot(dir_inode) && coda_iscontrol(name, len)) { |
| 326 | unlock_kernel(); |
| 327 | return -EPERM; |
| 328 | } |
| 329 | |
| 330 | symlen = strlen(symname); |
| 331 | if ( symlen > CODA_MAXPATHLEN ) { |
| 332 | unlock_kernel(); |
| 333 | return -ENAMETOOLONG; |
| 334 | } |
| 335 | |
| 336 | /* |
| 337 | * This entry is now negative. Since we do not create |
| 338 | * an inode for the entry we have to drop it. |
| 339 | */ |
| 340 | d_drop(de); |
| 341 | error = venus_symlink(dir_inode->i_sb, coda_i2f(dir_inode), name, len, |
| 342 | symname, symlen); |
| 343 | |
| 344 | /* mtime is no good anymore */ |
| 345 | if ( !error ) |
| 346 | coda_dir_changed(dir_inode, 0); |
| 347 | |
| 348 | unlock_kernel(); |
| 349 | return error; |
| 350 | } |
| 351 | |
| 352 | /* destruction routines: unlink, rmdir */ |
| 353 | int coda_unlink(struct inode *dir, struct dentry *de) |
| 354 | { |
| 355 | int error; |
| 356 | const char *name = de->d_name.name; |
| 357 | int len = de->d_name.len; |
| 358 | |
| 359 | lock_kernel(); |
| 360 | coda_vfs_stat.unlink++; |
| 361 | |
| 362 | error = venus_remove(dir->i_sb, coda_i2f(dir), name, len); |
| 363 | if ( error ) { |
| 364 | unlock_kernel(); |
| 365 | return error; |
| 366 | } |
| 367 | |
| 368 | coda_dir_changed(dir, 0); |
| 369 | de->d_inode->i_nlink--; |
| 370 | unlock_kernel(); |
| 371 | |
| 372 | return 0; |
| 373 | } |
| 374 | |
| 375 | int coda_rmdir(struct inode *dir, struct dentry *de) |
| 376 | { |
| 377 | const char *name = de->d_name.name; |
| 378 | int len = de->d_name.len; |
| 379 | int error; |
| 380 | |
| 381 | lock_kernel(); |
| 382 | coda_vfs_stat.rmdir++; |
| 383 | |
| 384 | if (!d_unhashed(de)) { |
| 385 | unlock_kernel(); |
| 386 | return -EBUSY; |
| 387 | } |
| 388 | error = venus_rmdir(dir->i_sb, coda_i2f(dir), name, len); |
| 389 | |
| 390 | if ( error ) { |
| 391 | unlock_kernel(); |
| 392 | return error; |
| 393 | } |
| 394 | |
| 395 | coda_dir_changed(dir, -1); |
| 396 | de->d_inode->i_nlink--; |
| 397 | d_delete(de); |
| 398 | unlock_kernel(); |
| 399 | |
| 400 | return 0; |
| 401 | } |
| 402 | |
| 403 | /* rename */ |
| 404 | static int coda_rename(struct inode *old_dir, struct dentry *old_dentry, |
| 405 | struct inode *new_dir, struct dentry *new_dentry) |
| 406 | { |
| 407 | const char *old_name = old_dentry->d_name.name; |
| 408 | const char *new_name = new_dentry->d_name.name; |
| 409 | int old_length = old_dentry->d_name.len; |
| 410 | int new_length = new_dentry->d_name.len; |
| 411 | int link_adjust = 0; |
| 412 | int error; |
| 413 | |
| 414 | lock_kernel(); |
| 415 | coda_vfs_stat.rename++; |
| 416 | |
| 417 | error = venus_rename(old_dir->i_sb, coda_i2f(old_dir), |
| 418 | coda_i2f(new_dir), old_length, new_length, |
| 419 | (const char *) old_name, (const char *)new_name); |
| 420 | |
| 421 | if ( !error ) { |
| 422 | if ( new_dentry->d_inode ) { |
| 423 | if ( S_ISDIR(new_dentry->d_inode->i_mode) ) |
| 424 | link_adjust = 1; |
| 425 | |
| 426 | coda_dir_changed(old_dir, -link_adjust); |
| 427 | coda_dir_changed(new_dir, link_adjust); |
| 428 | coda_flag_inode(new_dentry->d_inode, C_VATTR); |
| 429 | } else { |
| 430 | coda_flag_inode(old_dir, C_VATTR); |
| 431 | coda_flag_inode(new_dir, C_VATTR); |
| 432 | } |
| 433 | } |
| 434 | unlock_kernel(); |
| 435 | |
| 436 | return error; |
| 437 | } |
| 438 | |
| 439 | |
| 440 | /* file operations for directories */ |
| 441 | int coda_readdir(struct file *coda_file, void *dirent, filldir_t filldir) |
| 442 | { |
| 443 | struct dentry *coda_dentry = coda_file->f_dentry; |
| 444 | struct coda_file_info *cfi; |
| 445 | struct file *host_file; |
| 446 | struct inode *host_inode; |
| 447 | int ret; |
| 448 | |
| 449 | cfi = CODA_FTOC(coda_file); |
| 450 | BUG_ON(!cfi || cfi->cfi_magic != CODA_MAGIC); |
| 451 | host_file = cfi->cfi_container; |
| 452 | |
| 453 | coda_vfs_stat.readdir++; |
| 454 | |
| 455 | host_inode = host_file->f_dentry->d_inode; |
Jes Sorensen | 1b1dcc1 | 2006-01-09 15:59:24 -0800 | [diff] [blame] | 456 | mutex_lock(&host_inode->i_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 457 | host_file->f_pos = coda_file->f_pos; |
| 458 | |
| 459 | if (!host_file->f_op->readdir) { |
| 460 | /* Venus: we must read Venus dirents from the file */ |
| 461 | ret = coda_venus_readdir(host_file, filldir, dirent, coda_dentry); |
| 462 | } else { |
| 463 | /* potemkin case: we were handed a directory inode. */ |
| 464 | /* Yuk, we can't call vfs_readdir because we are already |
| 465 | * holding the inode semaphore. */ |
| 466 | ret = -ENOTDIR; |
| 467 | if (!host_file->f_op || !host_file->f_op->readdir) |
| 468 | goto out; |
| 469 | |
| 470 | ret = -ENOENT; |
| 471 | if (!IS_DEADDIR(host_inode)) { |
| 472 | ret = host_file->f_op->readdir(host_file, filldir, dirent); |
| 473 | file_accessed(host_file); |
| 474 | } |
| 475 | } |
| 476 | out: |
| 477 | coda_file->f_pos = host_file->f_pos; |
Jes Sorensen | 1b1dcc1 | 2006-01-09 15:59:24 -0800 | [diff] [blame] | 478 | mutex_unlock(&host_inode->i_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 479 | |
| 480 | return ret; |
| 481 | } |
| 482 | |
| 483 | static inline unsigned int CDT2DT(unsigned char cdt) |
| 484 | { |
| 485 | unsigned int dt; |
| 486 | |
| 487 | switch(cdt) { |
| 488 | case CDT_UNKNOWN: dt = DT_UNKNOWN; break; |
| 489 | case CDT_FIFO: dt = DT_FIFO; break; |
| 490 | case CDT_CHR: dt = DT_CHR; break; |
| 491 | case CDT_DIR: dt = DT_DIR; break; |
| 492 | case CDT_BLK: dt = DT_BLK; break; |
| 493 | case CDT_REG: dt = DT_REG; break; |
| 494 | case CDT_LNK: dt = DT_LNK; break; |
| 495 | case CDT_SOCK: dt = DT_SOCK; break; |
| 496 | case CDT_WHT: dt = DT_WHT; break; |
| 497 | default: dt = DT_UNKNOWN; break; |
| 498 | } |
| 499 | return dt; |
| 500 | } |
| 501 | |
| 502 | /* support routines */ |
| 503 | static int coda_venus_readdir(struct file *filp, filldir_t filldir, |
| 504 | void *dirent, struct dentry *dir) |
| 505 | { |
| 506 | int result = 0; /* # of entries returned */ |
| 507 | struct venus_dirent *vdir; |
| 508 | unsigned long vdir_size = |
| 509 | (unsigned long)(&((struct venus_dirent *)0)->d_name); |
| 510 | unsigned int type; |
| 511 | struct qstr name; |
| 512 | ino_t ino; |
| 513 | int ret, i; |
| 514 | |
| 515 | vdir = (struct venus_dirent *)kmalloc(sizeof(*vdir), GFP_KERNEL); |
| 516 | if (!vdir) return -ENOMEM; |
| 517 | |
| 518 | i = filp->f_pos; |
| 519 | switch(i) { |
| 520 | case 0: |
| 521 | ret = filldir(dirent, ".", 1, 0, dir->d_inode->i_ino, DT_DIR); |
| 522 | if (ret < 0) break; |
| 523 | result++; |
| 524 | filp->f_pos++; |
| 525 | /* fallthrough */ |
| 526 | case 1: |
| 527 | ret = filldir(dirent, "..", 2, 1, dir->d_parent->d_inode->i_ino, DT_DIR); |
| 528 | if (ret < 0) break; |
| 529 | result++; |
| 530 | filp->f_pos++; |
| 531 | /* fallthrough */ |
| 532 | default: |
| 533 | while (1) { |
| 534 | /* read entries from the directory file */ |
| 535 | ret = kernel_read(filp, filp->f_pos - 2, (char *)vdir, |
| 536 | sizeof(*vdir)); |
| 537 | if (ret < 0) { |
| 538 | printk("coda_venus_readdir: read dir failed %d\n", ret); |
| 539 | break; |
| 540 | } |
| 541 | if (ret == 0) break; /* end of directory file reached */ |
| 542 | |
| 543 | /* catch truncated reads */ |
| 544 | if (ret < vdir_size || ret < vdir_size + vdir->d_namlen) { |
| 545 | printk("coda_venus_readdir: short read: %ld\n", |
| 546 | filp->f_dentry->d_inode->i_ino); |
| 547 | ret = -EBADF; |
| 548 | break; |
| 549 | } |
| 550 | /* validate whether the directory file actually makes sense */ |
| 551 | if (vdir->d_reclen < vdir_size + vdir->d_namlen) { |
| 552 | printk("coda_venus_readdir: Invalid dir: %ld\n", |
| 553 | filp->f_dentry->d_inode->i_ino); |
| 554 | ret = -EBADF; |
| 555 | break; |
| 556 | } |
| 557 | |
| 558 | name.len = vdir->d_namlen; |
| 559 | name.name = vdir->d_name; |
| 560 | |
| 561 | /* Make sure we skip '.' and '..', we already got those */ |
| 562 | if (name.name[0] == '.' && (name.len == 1 || |
| 563 | (vdir->d_name[1] == '.' && name.len == 2))) |
| 564 | vdir->d_fileno = name.len = 0; |
| 565 | |
| 566 | /* skip null entries */ |
| 567 | if (vdir->d_fileno && name.len) { |
| 568 | /* try to look up this entry in the dcache, that way |
| 569 | * userspace doesn't have to worry about breaking |
| 570 | * getcwd by having mismatched inode numbers for |
| 571 | * internal volume mountpoints. */ |
| 572 | ino = find_inode_number(dir, &name); |
| 573 | if (!ino) ino = vdir->d_fileno; |
| 574 | |
| 575 | type = CDT2DT(vdir->d_type); |
| 576 | ret = filldir(dirent, name.name, name.len, filp->f_pos, |
| 577 | ino, type); |
| 578 | /* failure means no space for filling in this round */ |
| 579 | if (ret < 0) break; |
| 580 | result++; |
| 581 | } |
| 582 | /* we'll always have progress because d_reclen is unsigned and |
| 583 | * we've already established it is non-zero. */ |
| 584 | filp->f_pos += vdir->d_reclen; |
| 585 | } |
| 586 | } |
| 587 | kfree(vdir); |
| 588 | return result ? result : ret; |
| 589 | } |
| 590 | |
| 591 | /* called when a cache lookup succeeds */ |
| 592 | static int coda_dentry_revalidate(struct dentry *de, struct nameidata *nd) |
| 593 | { |
| 594 | struct inode *inode = de->d_inode; |
| 595 | struct coda_inode_info *cii; |
| 596 | |
| 597 | if (!inode) |
| 598 | return 1; |
| 599 | lock_kernel(); |
| 600 | if (coda_isroot(inode)) |
| 601 | goto out; |
| 602 | if (is_bad_inode(inode)) |
| 603 | goto bad; |
| 604 | |
| 605 | cii = ITOC(de->d_inode); |
| 606 | if (!(cii->c_flags & (C_PURGE | C_FLUSH))) |
| 607 | goto out; |
| 608 | |
| 609 | shrink_dcache_parent(de); |
| 610 | |
| 611 | /* propagate for a flush */ |
| 612 | if (cii->c_flags & C_FLUSH) |
| 613 | coda_flag_inode_children(inode, C_FLUSH); |
| 614 | |
| 615 | if (atomic_read(&de->d_count) > 1) |
| 616 | /* pretend it's valid, but don't change the flags */ |
| 617 | goto out; |
| 618 | |
| 619 | /* clear the flags. */ |
| 620 | cii->c_flags &= ~(C_VATTR | C_PURGE | C_FLUSH); |
| 621 | |
| 622 | bad: |
| 623 | unlock_kernel(); |
| 624 | return 0; |
| 625 | out: |
| 626 | unlock_kernel(); |
| 627 | return 1; |
| 628 | } |
| 629 | |
| 630 | /* |
| 631 | * This is the callback from dput() when d_count is going to 0. |
| 632 | * We use this to unhash dentries with bad inodes. |
| 633 | */ |
| 634 | static int coda_dentry_delete(struct dentry * dentry) |
| 635 | { |
| 636 | int flags; |
| 637 | |
| 638 | if (!dentry->d_inode) |
| 639 | return 0; |
| 640 | |
| 641 | flags = (ITOC(dentry->d_inode)->c_flags) & C_PURGE; |
| 642 | if (is_bad_inode(dentry->d_inode) || flags) { |
| 643 | return 1; |
| 644 | } |
| 645 | return 0; |
| 646 | } |
| 647 | |
| 648 | |
| 649 | |
| 650 | /* |
| 651 | * This is called when we want to check if the inode has |
| 652 | * changed on the server. Coda makes this easy since the |
| 653 | * cache manager Venus issues a downcall to the kernel when this |
| 654 | * happens |
| 655 | */ |
| 656 | int coda_revalidate_inode(struct dentry *dentry) |
| 657 | { |
| 658 | struct coda_vattr attr; |
| 659 | int error = 0; |
| 660 | int old_mode; |
| 661 | ino_t old_ino; |
| 662 | struct inode *inode = dentry->d_inode; |
| 663 | struct coda_inode_info *cii = ITOC(inode); |
| 664 | |
| 665 | lock_kernel(); |
| 666 | if ( !cii->c_flags ) |
| 667 | goto ok; |
| 668 | |
| 669 | if (cii->c_flags & (C_VATTR | C_PURGE | C_FLUSH)) { |
| 670 | error = venus_getattr(inode->i_sb, &(cii->c_fid), &attr); |
| 671 | if ( error ) |
| 672 | goto return_bad; |
| 673 | |
| 674 | /* this inode may be lost if: |
| 675 | - it's ino changed |
| 676 | - type changes must be permitted for repair and |
| 677 | missing mount points. |
| 678 | */ |
| 679 | old_mode = inode->i_mode; |
| 680 | old_ino = inode->i_ino; |
| 681 | coda_vattr_to_iattr(inode, &attr); |
| 682 | |
| 683 | if ((old_mode & S_IFMT) != (inode->i_mode & S_IFMT)) { |
| 684 | printk("Coda: inode %ld, fid %s changed type!\n", |
| 685 | inode->i_ino, coda_f2s(&(cii->c_fid))); |
| 686 | } |
| 687 | |
| 688 | /* the following can happen when a local fid is replaced |
| 689 | with a global one, here we lose and declare the inode bad */ |
| 690 | if (inode->i_ino != old_ino) |
| 691 | goto return_bad; |
| 692 | |
| 693 | coda_flag_inode_children(inode, C_FLUSH); |
| 694 | cii->c_flags &= ~(C_VATTR | C_PURGE | C_FLUSH); |
| 695 | } |
| 696 | |
| 697 | ok: |
| 698 | unlock_kernel(); |
| 699 | return 0; |
| 700 | |
| 701 | return_bad: |
| 702 | unlock_kernel(); |
| 703 | return -EIO; |
| 704 | } |