1 #define MSNFS /* HACK HACK */ 2 /* 3 * linux/fs/nfsd/vfs.c 4 * 5 * File operations used by nfsd. Some of these have been ripped from 6 * other parts of the kernel because they weren't exported, others 7 * are partial duplicates with added or changed functionality. 8 * 9 * Note that several functions dget() the dentry upon which they want 10 * to act, most notably those that create directory entries. Response 11 * dentry's are dput()'d if necessary in the release callback. 12 * So if you notice code paths that apparently fail to dput() the 13 * dentry, don't worry--they have been taken care of. 14 * 15 * Copyright (C) 1995-1999 Olaf Kirch <okir@monad.swb.de> 16 * Zerocpy NFS support (C) 2002 Hirokazu Takahashi <taka@valinux.co.jp> 17 */ 18 19 #include <linux/config.h> 20 #include <linux/string.h> 21 #include <linux/time.h> 22 #include <linux/errno.h> 23 #include <linux/fs.h> 24 #include <linux/file.h> 25 #include <linux/mount.h> 26 #include <linux/major.h> 27 #include <linux/ext2_fs.h> 28 #include <linux/proc_fs.h> 29 #include <linux/stat.h> 30 #include <linux/fcntl.h> 31 #include <linux/net.h> 32 #include <linux/unistd.h> 33 #include <linux/slab.h> 34 #include <linux/pagemap.h> 35 #include <linux/in.h> 36 #include <linux/module.h> 37 #include <linux/namei.h> 38 #include <linux/vfs.h> 39 #include <linux/delay.h> 40 #include <linux/sunrpc/svc.h> 41 #include <linux/nfsd/nfsd.h> 42 #ifdef CONFIG_NFSD_V3 43 #include <linux/nfs3.h> 44 #include <linux/nfsd/xdr3.h> 45 #endif /* CONFIG_NFSD_V3 */ 46 #include <linux/nfsd/nfsfh.h> 47 #include <linux/quotaops.h> 48 #include <linux/fsnotify.h> 49 #include <linux/posix_acl.h> 50 #include <linux/posix_acl_xattr.h> 51 #ifdef CONFIG_NFSD_V4 52 #include <linux/xattr.h> 53 #include <linux/nfs4.h> 54 #include <linux/nfs4_acl.h> 55 #include <linux/nfsd_idmap.h> 56 #include <linux/security.h> 57 #endif /* CONFIG_NFSD_V4 */ 58 59 #include <asm/uaccess.h> 60 61 #define NFSDDBG_FACILITY NFSDDBG_FILEOP 62 #define NFSD_PARANOIA 63 64 65 /* We must ignore files (but only files) which might have mandatory 66 * locks on them because there is no way to know if the accesser has 67 * the lock. 68 */ 69 #define IS_ISMNDLK(i) (S_ISREG((i)->i_mode) && MANDATORY_LOCK(i)) 70 71 /* 72 * This is a cache of readahead params that help us choose the proper 73 * readahead strategy. Initially, we set all readahead parameters to 0 74 * and let the VFS handle things. 75 * If you increase the number of cached files very much, you'll need to 76 * add a hash table here. 77 */ 78 struct raparms { 79 struct raparms *p_next; 80 unsigned int p_count; 81 ino_t p_ino; 82 dev_t p_dev; 83 int p_set; 84 struct file_ra_state p_ra; 85 }; 86 87 static struct raparms * raparml; 88 static struct raparms * raparm_cache; 89 90 /* 91 * Called from nfsd_lookup and encode_dirent. Check if we have crossed 92 * a mount point. 93 * Returns -EAGAIN leaving *dpp and *expp unchanged, 94 * or nfs_ok having possibly changed *dpp and *expp 95 */ 96 int 97 nfsd_cross_mnt(struct svc_rqst *rqstp, struct dentry **dpp, 98 struct svc_export **expp) 99 { 100 struct svc_export *exp = *expp, *exp2 = NULL; 101 struct dentry *dentry = *dpp; 102 struct vfsmount *mnt = mntget(exp->ex_mnt); 103 struct dentry *mounts = dget(dentry); 104 int err = nfs_ok; 105 106 while (follow_down(&mnt,&mounts)&&d_mountpoint(mounts)); 107 108 exp2 = exp_get_by_name(exp->ex_client, mnt, mounts, &rqstp->rq_chandle); 109 if (IS_ERR(exp2)) { 110 err = PTR_ERR(exp2); 111 dput(mounts); 112 mntput(mnt); 113 goto out; 114 } 115 if (exp2 && ((exp->ex_flags & NFSEXP_CROSSMOUNT) || EX_NOHIDE(exp2))) { 116 /* successfully crossed mount point */ 117 exp_put(exp); 118 *expp = exp2; 119 dput(dentry); 120 *dpp = mounts; 121 } else { 122 if (exp2) exp_put(exp2); 123 dput(mounts); 124 } 125 mntput(mnt); 126 out: 127 return err; 128 } 129 130 /* 131 * Look up one component of a pathname. 132 * N.B. After this call _both_ fhp and resfh need an fh_put 133 * 134 * If the lookup would cross a mountpoint, and the mounted filesystem 135 * is exported to the client with NFSEXP_NOHIDE, then the lookup is 136 * accepted as it stands and the mounted directory is 137 * returned. Otherwise the covered directory is returned. 138 * NOTE: this mountpoint crossing is not supported properly by all 139 * clients and is explicitly disallowed for NFSv3 140 * NeilBrown <neilb@cse.unsw.edu.au> 141 */ 142 int 143 nfsd_lookup(struct svc_rqst *rqstp, struct svc_fh *fhp, const char *name, 144 int len, struct svc_fh *resfh) 145 { 146 struct svc_export *exp; 147 struct dentry *dparent; 148 struct dentry *dentry; 149 int err; 150 151 dprintk("nfsd: nfsd_lookup(fh %s, %.*s)\n", SVCFH_fmt(fhp), len,name); 152 153 /* Obtain dentry and export. */ 154 err = fh_verify(rqstp, fhp, S_IFDIR, MAY_EXEC); 155 if (err) 156 return err; 157 158 dparent = fhp->fh_dentry; 159 exp = fhp->fh_export; 160 exp_get(exp); 161 162 err = nfserr_acces; 163 164 /* Lookup the name, but don't follow links */ 165 if (isdotent(name, len)) { 166 if (len==1) 167 dentry = dget(dparent); 168 else if (dparent != exp->ex_dentry) { 169 dentry = dget_parent(dparent); 170 } else if (!EX_NOHIDE(exp)) 171 dentry = dget(dparent); /* .. == . just like at / */ 172 else { 173 /* checking mountpoint crossing is very different when stepping up */ 174 struct svc_export *exp2 = NULL; 175 struct dentry *dp; 176 struct vfsmount *mnt = mntget(exp->ex_mnt); 177 dentry = dget(dparent); 178 while(dentry == mnt->mnt_root && follow_up(&mnt, &dentry)) 179 ; 180 dp = dget_parent(dentry); 181 dput(dentry); 182 dentry = dp; 183 184 exp2 = exp_parent(exp->ex_client, mnt, dentry, 185 &rqstp->rq_chandle); 186 if (IS_ERR(exp2)) { 187 err = PTR_ERR(exp2); 188 dput(dentry); 189 mntput(mnt); 190 goto out_nfserr; 191 } 192 if (!exp2) { 193 dput(dentry); 194 dentry = dget(dparent); 195 } else { 196 exp_put(exp); 197 exp = exp2; 198 } 199 mntput(mnt); 200 } 201 } else { 202 fh_lock(fhp); 203 dentry = lookup_one_len(name, dparent, len); 204 err = PTR_ERR(dentry); 205 if (IS_ERR(dentry)) 206 goto out_nfserr; 207 /* 208 * check if we have crossed a mount point ... 209 */ 210 if (d_mountpoint(dentry)) { 211 if ((err = nfsd_cross_mnt(rqstp, &dentry, &exp))) { 212 dput(dentry); 213 goto out_nfserr; 214 } 215 } 216 } 217 /* 218 * Note: we compose the file handle now, but as the 219 * dentry may be negative, it may need to be updated. 220 */ 221 err = fh_compose(resfh, exp, dentry, fhp); 222 if (!err && !dentry->d_inode) 223 err = nfserr_noent; 224 dput(dentry); 225 out: 226 exp_put(exp); 227 return err; 228 229 out_nfserr: 230 err = nfserrno(err); 231 goto out; 232 } 233 234 /* 235 * Set various file attributes. 236 * N.B. After this call fhp needs an fh_put 237 */ 238 int 239 nfsd_setattr(struct svc_rqst *rqstp, struct svc_fh *fhp, struct iattr *iap, 240 int check_guard, time_t guardtime) 241 { 242 struct dentry *dentry; 243 struct inode *inode; 244 int accmode = MAY_SATTR; 245 int ftype = 0; 246 int imode; 247 int err; 248 int size_change = 0; 249 250 if (iap->ia_valid & (ATTR_ATIME | ATTR_MTIME | ATTR_SIZE)) 251 accmode |= MAY_WRITE|MAY_OWNER_OVERRIDE; 252 if (iap->ia_valid & ATTR_SIZE) 253 ftype = S_IFREG; 254 255 /* Get inode */ 256 err = fh_verify(rqstp, fhp, ftype, accmode); 257 if (err) 258 goto out; 259 260 dentry = fhp->fh_dentry; 261 inode = dentry->d_inode; 262 263 /* Ignore any mode updates on symlinks */ 264 if (S_ISLNK(inode->i_mode)) 265 iap->ia_valid &= ~ATTR_MODE; 266 267 if (!iap->ia_valid) 268 goto out; 269 270 /* NFSv2 does not differentiate between "set-[ac]time-to-now" 271 * which only requires access, and "set-[ac]time-to-X" which 272 * requires ownership. 273 * So if it looks like it might be "set both to the same time which 274 * is close to now", and if inode_change_ok fails, then we 275 * convert to "set to now" instead of "set to explicit time" 276 * 277 * We only call inode_change_ok as the last test as technically 278 * it is not an interface that we should be using. It is only 279 * valid if the filesystem does not define it's own i_op->setattr. 280 */ 281 #define BOTH_TIME_SET (ATTR_ATIME_SET | ATTR_MTIME_SET) 282 #define MAX_TOUCH_TIME_ERROR (30*60) 283 if ((iap->ia_valid & BOTH_TIME_SET) == BOTH_TIME_SET 284 && iap->ia_mtime.tv_sec == iap->ia_atime.tv_sec 285 ) { 286 /* Looks probable. Now just make sure time is in the right ballpark. 287 * Solaris, at least, doesn't seem to care what the time request is. 288 * We require it be within 30 minutes of now. 289 */ 290 time_t delta = iap->ia_atime.tv_sec - get_seconds(); 291 if (delta<0) delta = -delta; 292 if (delta < MAX_TOUCH_TIME_ERROR && 293 inode_change_ok(inode, iap) != 0) { 294 /* turn off ATTR_[AM]TIME_SET but leave ATTR_[AM]TIME 295 * this will cause notify_change to set these times to "now" 296 */ 297 iap->ia_valid &= ~BOTH_TIME_SET; 298 } 299 } 300 301 /* The size case is special. It changes the file as well as the attributes. */ 302 if (iap->ia_valid & ATTR_SIZE) { 303 if (iap->ia_size < inode->i_size) { 304 err = nfsd_permission(fhp->fh_export, dentry, MAY_TRUNC|MAY_OWNER_OVERRIDE); 305 if (err) 306 goto out; 307 } 308 309 /* 310 * If we are changing the size of the file, then 311 * we need to break all leases. 312 */ 313 err = break_lease(inode, FMODE_WRITE | O_NONBLOCK); 314 if (err == -EWOULDBLOCK) 315 err = -ETIMEDOUT; 316 if (err) /* ENOMEM or EWOULDBLOCK */ 317 goto out_nfserr; 318 319 err = get_write_access(inode); 320 if (err) 321 goto out_nfserr; 322 323 size_change = 1; 324 err = locks_verify_truncate(inode, NULL, iap->ia_size); 325 if (err) { 326 put_write_access(inode); 327 goto out_nfserr; 328 } 329 DQUOT_INIT(inode); 330 } 331 332 imode = inode->i_mode; 333 if (iap->ia_valid & ATTR_MODE) { 334 iap->ia_mode &= S_IALLUGO; 335 imode = iap->ia_mode |= (imode & ~S_IALLUGO); 336 } 337 338 /* Revoke setuid/setgid bit on chown/chgrp */ 339 if ((iap->ia_valid & ATTR_UID) && iap->ia_uid != inode->i_uid) 340 iap->ia_valid |= ATTR_KILL_SUID; 341 if ((iap->ia_valid & ATTR_GID) && iap->ia_gid != inode->i_gid) 342 iap->ia_valid |= ATTR_KILL_SGID; 343 344 /* Change the attributes. */ 345 346 iap->ia_valid |= ATTR_CTIME; 347 348 err = nfserr_notsync; 349 if (!check_guard || guardtime == inode->i_ctime.tv_sec) { 350 fh_lock(fhp); 351 err = notify_change(dentry, iap); 352 err = nfserrno(err); 353 fh_unlock(fhp); 354 } 355 if (size_change) 356 put_write_access(inode); 357 if (!err) 358 if (EX_ISSYNC(fhp->fh_export)) 359 write_inode_now(inode, 1); 360 out: 361 return err; 362 363 out_nfserr: 364 err = nfserrno(err); 365 goto out; 366 } 367 368 #if defined(CONFIG_NFSD_V4) 369 370 static int 371 set_nfsv4_acl_one(struct dentry *dentry, struct posix_acl *pacl, char *key) 372 { 373 int len; 374 size_t buflen; 375 char *buf = NULL; 376 int error = 0; 377 struct inode *inode = dentry->d_inode; 378 379 buflen = posix_acl_xattr_size(pacl->a_count); 380 buf = kmalloc(buflen, GFP_KERNEL); 381 error = -ENOMEM; 382 if (buf == NULL) 383 goto out; 384 385 len = posix_acl_to_xattr(pacl, buf, buflen); 386 if (len < 0) { 387 error = len; 388 goto out; 389 } 390 391 error = -EOPNOTSUPP; 392 if (inode->i_op && inode->i_op->setxattr) { 393 down(&inode->i_sem); 394 security_inode_setxattr(dentry, key, buf, len, 0); 395 error = inode->i_op->setxattr(dentry, key, buf, len, 0); 396 if (!error) 397 security_inode_post_setxattr(dentry, key, buf, len, 0); 398 up(&inode->i_sem); 399 } 400 out: 401 kfree(buf); 402 return error; 403 } 404 405 int 406 nfsd4_set_nfs4_acl(struct svc_rqst *rqstp, struct svc_fh *fhp, 407 struct nfs4_acl *acl) 408 { 409 int error; 410 struct dentry *dentry; 411 struct inode *inode; 412 struct posix_acl *pacl = NULL, *dpacl = NULL; 413 unsigned int flags = 0; 414 415 /* Get inode */ 416 error = fh_verify(rqstp, fhp, 0 /* S_IFREG */, MAY_SATTR); 417 if (error) 418 goto out; 419 420 dentry = fhp->fh_dentry; 421 inode = dentry->d_inode; 422 if (S_ISDIR(inode->i_mode)) 423 flags = NFS4_ACL_DIR; 424 425 error = nfs4_acl_nfsv4_to_posix(acl, &pacl, &dpacl, flags); 426 if (error == -EINVAL) { 427 error = nfserr_attrnotsupp; 428 goto out; 429 } else if (error < 0) 430 goto out_nfserr; 431 432 if (pacl) { 433 error = set_nfsv4_acl_one(dentry, pacl, POSIX_ACL_XATTR_ACCESS); 434 if (error < 0) 435 goto out_nfserr; 436 } 437 438 if (dpacl) { 439 error = set_nfsv4_acl_one(dentry, dpacl, POSIX_ACL_XATTR_DEFAULT); 440 if (error < 0) 441 goto out_nfserr; 442 } 443 444 error = nfs_ok; 445 446 out: 447 posix_acl_release(pacl); 448 posix_acl_release(dpacl); 449 return (error); 450 out_nfserr: 451 error = nfserrno(error); 452 goto out; 453 } 454 455 static struct posix_acl * 456 _get_posix_acl(struct dentry *dentry, char *key) 457 { 458 struct inode *inode = dentry->d_inode; 459 char *buf = NULL; 460 int buflen, error = 0; 461 struct posix_acl *pacl = NULL; 462 463 error = -EOPNOTSUPP; 464 if (inode->i_op == NULL) 465 goto out_err; 466 if (inode->i_op->getxattr == NULL) 467 goto out_err; 468 469 error = security_inode_getxattr(dentry, key); 470 if (error) 471 goto out_err; 472 473 buflen = inode->i_op->getxattr(dentry, key, NULL, 0); 474 if (buflen <= 0) { 475 error = buflen < 0 ? buflen : -ENODATA; 476 goto out_err; 477 } 478 479 buf = kmalloc(buflen, GFP_KERNEL); 480 if (buf == NULL) { 481 error = -ENOMEM; 482 goto out_err; 483 } 484 485 error = inode->i_op->getxattr(dentry, key, buf, buflen); 486 if (error < 0) 487 goto out_err; 488 489 pacl = posix_acl_from_xattr(buf, buflen); 490 out: 491 kfree(buf); 492 return pacl; 493 out_err: 494 pacl = ERR_PTR(error); 495 goto out; 496 } 497 498 int 499 nfsd4_get_nfs4_acl(struct svc_rqst *rqstp, struct dentry *dentry, struct nfs4_acl **acl) 500 { 501 struct inode *inode = dentry->d_inode; 502 int error = 0; 503 struct posix_acl *pacl = NULL, *dpacl = NULL; 504 unsigned int flags = 0; 505 506 pacl = _get_posix_acl(dentry, POSIX_ACL_XATTR_ACCESS); 507 if (IS_ERR(pacl) && PTR_ERR(pacl) == -ENODATA) 508 pacl = posix_acl_from_mode(inode->i_mode, GFP_KERNEL); 509 if (IS_ERR(pacl)) { 510 error = PTR_ERR(pacl); 511 pacl = NULL; 512 goto out; 513 } 514 515 if (S_ISDIR(inode->i_mode)) { 516 dpacl = _get_posix_acl(dentry, POSIX_ACL_XATTR_DEFAULT); 517 if (IS_ERR(dpacl) && PTR_ERR(dpacl) == -ENODATA) 518 dpacl = NULL; 519 else if (IS_ERR(dpacl)) { 520 error = PTR_ERR(dpacl); 521 dpacl = NULL; 522 goto out; 523 } 524 flags = NFS4_ACL_DIR; 525 } 526 527 *acl = nfs4_acl_posix_to_nfsv4(pacl, dpacl, flags); 528 if (IS_ERR(*acl)) { 529 error = PTR_ERR(*acl); 530 *acl = NULL; 531 } 532 out: 533 posix_acl_release(pacl); 534 posix_acl_release(dpacl); 535 return error; 536 } 537 538 #endif /* defined(CONFIG_NFS_V4) */ 539 540 #ifdef CONFIG_NFSD_V3 541 /* 542 * Check server access rights to a file system object 543 */ 544 struct accessmap { 545 u32 access; 546 int how; 547 }; 548 static struct accessmap nfs3_regaccess[] = { 549 { NFS3_ACCESS_READ, MAY_READ }, 550 { NFS3_ACCESS_EXECUTE, MAY_EXEC }, 551 { NFS3_ACCESS_MODIFY, MAY_WRITE|MAY_TRUNC }, 552 { NFS3_ACCESS_EXTEND, MAY_WRITE }, 553 554 { 0, 0 } 555 }; 556 557 static struct accessmap nfs3_diraccess[] = { 558 { NFS3_ACCESS_READ, MAY_READ }, 559 { NFS3_ACCESS_LOOKUP, MAY_EXEC }, 560 { NFS3_ACCESS_MODIFY, MAY_EXEC|MAY_WRITE|MAY_TRUNC }, 561 { NFS3_ACCESS_EXTEND, MAY_EXEC|MAY_WRITE }, 562 { NFS3_ACCESS_DELETE, MAY_REMOVE }, 563 564 { 0, 0 } 565 }; 566 567 static struct accessmap nfs3_anyaccess[] = { 568 /* Some clients - Solaris 2.6 at least, make an access call 569 * to the server to check for access for things like /dev/null 570 * (which really, the server doesn't care about). So 571 * We provide simple access checking for them, looking 572 * mainly at mode bits, and we make sure to ignore read-only 573 * filesystem checks 574 */ 575 { NFS3_ACCESS_READ, MAY_READ }, 576 { NFS3_ACCESS_EXECUTE, MAY_EXEC }, 577 { NFS3_ACCESS_MODIFY, MAY_WRITE|MAY_LOCAL_ACCESS }, 578 { NFS3_ACCESS_EXTEND, MAY_WRITE|MAY_LOCAL_ACCESS }, 579 580 { 0, 0 } 581 }; 582 583 int 584 nfsd_access(struct svc_rqst *rqstp, struct svc_fh *fhp, u32 *access, u32 *supported) 585 { 586 struct accessmap *map; 587 struct svc_export *export; 588 struct dentry *dentry; 589 u32 query, result = 0, sresult = 0; 590 unsigned int error; 591 592 error = fh_verify(rqstp, fhp, 0, MAY_NOP); 593 if (error) 594 goto out; 595 596 export = fhp->fh_export; 597 dentry = fhp->fh_dentry; 598 599 if (S_ISREG(dentry->d_inode->i_mode)) 600 map = nfs3_regaccess; 601 else if (S_ISDIR(dentry->d_inode->i_mode)) 602 map = nfs3_diraccess; 603 else 604 map = nfs3_anyaccess; 605 606 607 query = *access; 608 for (; map->access; map++) { 609 if (map->access & query) { 610 unsigned int err2; 611 612 sresult |= map->access; 613 614 err2 = nfsd_permission(export, dentry, map->how); 615 switch (err2) { 616 case nfs_ok: 617 result |= map->access; 618 break; 619 620 /* the following error codes just mean the access was not allowed, 621 * rather than an error occurred */ 622 case nfserr_rofs: 623 case nfserr_acces: 624 case nfserr_perm: 625 /* simply don't "or" in the access bit. */ 626 break; 627 default: 628 error = err2; 629 goto out; 630 } 631 } 632 } 633 *access = result; 634 if (supported) 635 *supported = sresult; 636 637 out: 638 return error; 639 } 640 #endif /* CONFIG_NFSD_V3 */ 641 642 643 644 /* 645 * Open an existing file or directory. 646 * The access argument indicates the type of open (read/write/lock) 647 * N.B. After this call fhp needs an fh_put 648 */ 649 int 650 nfsd_open(struct svc_rqst *rqstp, struct svc_fh *fhp, int type, 651 int access, struct file **filp) 652 { 653 struct dentry *dentry; 654 struct inode *inode; 655 int flags = O_RDONLY|O_LARGEFILE, err; 656 657 /* 658 * If we get here, then the client has already done an "open", 659 * and (hopefully) checked permission - so allow OWNER_OVERRIDE 660 * in case a chmod has now revoked permission. 661 */ 662 err = fh_verify(rqstp, fhp, type, access | MAY_OWNER_OVERRIDE); 663 if (err) 664 goto out; 665 666 dentry = fhp->fh_dentry; 667 inode = dentry->d_inode; 668 669 /* Disallow write access to files with the append-only bit set 670 * or any access when mandatory locking enabled 671 */ 672 err = nfserr_perm; 673 if (IS_APPEND(inode) && (access & MAY_WRITE)) 674 goto out; 675 if (IS_ISMNDLK(inode)) 676 goto out; 677 678 if (!inode->i_fop) 679 goto out; 680 681 /* 682 * Check to see if there are any leases on this file. 683 * This may block while leases are broken. 684 */ 685 err = break_lease(inode, O_NONBLOCK | ((access & MAY_WRITE) ? FMODE_WRITE : 0)); 686 if (err == -EWOULDBLOCK) 687 err = -ETIMEDOUT; 688 if (err) /* NOMEM or WOULDBLOCK */ 689 goto out_nfserr; 690 691 if (access & MAY_WRITE) { 692 flags = O_WRONLY|O_LARGEFILE; 693 694 DQUOT_INIT(inode); 695 } 696 *filp = dentry_open(dget(dentry), mntget(fhp->fh_export->ex_mnt), flags); 697 if (IS_ERR(*filp)) 698 err = PTR_ERR(*filp); 699 out_nfserr: 700 if (err) 701 err = nfserrno(err); 702 out: 703 return err; 704 } 705 706 /* 707 * Close a file. 708 */ 709 void 710 nfsd_close(struct file *filp) 711 { 712 fput(filp); 713 } 714 715 /* 716 * Sync a file 717 * As this calls fsync (not fdatasync) there is no need for a write_inode 718 * after it. 719 */ 720 static inline void nfsd_dosync(struct file *filp, struct dentry *dp, 721 struct file_operations *fop) 722 { 723 struct inode *inode = dp->d_inode; 724 int (*fsync) (struct file *, struct dentry *, int); 725 726 filemap_fdatawrite(inode->i_mapping); 727 if (fop && (fsync = fop->fsync)) 728 fsync(filp, dp, 0); 729 filemap_fdatawait(inode->i_mapping); 730 } 731 732 733 static void 734 nfsd_sync(struct file *filp) 735 { 736 struct inode *inode = filp->f_dentry->d_inode; 737 dprintk("nfsd: sync file %s\n", filp->f_dentry->d_name.name); 738 down(&inode->i_sem); 739 nfsd_dosync(filp, filp->f_dentry, filp->f_op); 740 up(&inode->i_sem); 741 } 742 743 void 744 nfsd_sync_dir(struct dentry *dp) 745 { 746 nfsd_dosync(NULL, dp, dp->d_inode->i_fop); 747 } 748 749 /* 750 * Obtain the readahead parameters for the file 751 * specified by (dev, ino). 752 */ 753 static DEFINE_SPINLOCK(ra_lock); 754 755 static inline struct raparms * 756 nfsd_get_raparms(dev_t dev, ino_t ino) 757 { 758 struct raparms *ra, **rap, **frap = NULL; 759 int depth = 0; 760 761 spin_lock(&ra_lock); 762 for (rap = &raparm_cache; (ra = *rap); rap = &ra->p_next) { 763 if (ra->p_ino == ino && ra->p_dev == dev) 764 goto found; 765 depth++; 766 if (ra->p_count == 0) 767 frap = rap; 768 } 769 depth = nfsdstats.ra_size*11/10; 770 if (!frap) { 771 spin_unlock(&ra_lock); 772 return NULL; 773 } 774 rap = frap; 775 ra = *frap; 776 ra->p_dev = dev; 777 ra->p_ino = ino; 778 ra->p_set = 0; 779 found: 780 if (rap != &raparm_cache) { 781 *rap = ra->p_next; 782 ra->p_next = raparm_cache; 783 raparm_cache = ra; 784 } 785 ra->p_count++; 786 nfsdstats.ra_depth[depth*10/nfsdstats.ra_size]++; 787 spin_unlock(&ra_lock); 788 return ra; 789 } 790 791 /* 792 * Grab and keep cached pages assosiated with a file in the svc_rqst 793 * so that they can be passed to the netowork sendmsg/sendpage routines 794 * directrly. They will be released after the sending has completed. 795 */ 796 static int 797 nfsd_read_actor(read_descriptor_t *desc, struct page *page, unsigned long offset , unsigned long size) 798 { 799 unsigned long count = desc->count; 800 struct svc_rqst *rqstp = desc->arg.data; 801 802 if (size > count) 803 size = count; 804 805 if (rqstp->rq_res.page_len == 0) { 806 get_page(page); 807 rqstp->rq_respages[rqstp->rq_resused++] = page; 808 rqstp->rq_res.page_base = offset; 809 rqstp->rq_res.page_len = size; 810 } else if (page != rqstp->rq_respages[rqstp->rq_resused-1]) { 811 get_page(page); 812 rqstp->rq_respages[rqstp->rq_resused++] = page; 813 rqstp->rq_res.page_len += size; 814 } else { 815 rqstp->rq_res.page_len += size; 816 } 817 818 desc->count = count - size; 819 desc->written += size; 820 return size; 821 } 822 823 static inline int 824 nfsd_vfs_read(struct svc_rqst *rqstp, struct svc_fh *fhp, struct file *file, 825 loff_t offset, struct kvec *vec, int vlen, unsigned long *count) 826 { 827 struct inode *inode; 828 struct raparms *ra; 829 mm_segment_t oldfs; 830 int err; 831 832 err = nfserr_perm; 833 inode = file->f_dentry->d_inode; 834 #ifdef MSNFS 835 if ((fhp->fh_export->ex_flags & NFSEXP_MSNFS) && 836 (!lock_may_read(inode, offset, *count))) 837 goto out; 838 #endif 839 840 /* Get readahead parameters */ 841 ra = nfsd_get_raparms(inode->i_sb->s_dev, inode->i_ino); 842 843 if (ra && ra->p_set) 844 file->f_ra = ra->p_ra; 845 846 if (file->f_op->sendfile) { 847 svc_pushback_unused_pages(rqstp); 848 err = file->f_op->sendfile(file, &offset, *count, 849 nfsd_read_actor, rqstp); 850 } else { 851 oldfs = get_fs(); 852 set_fs(KERNEL_DS); 853 err = vfs_readv(file, (struct iovec __user *)vec, vlen, &offset); 854 set_fs(oldfs); 855 } 856 857 /* Write back readahead params */ 858 if (ra) { 859 spin_lock(&ra_lock); 860 ra->p_ra = file->f_ra; 861 ra->p_set = 1; 862 ra->p_count--; 863 spin_unlock(&ra_lock); 864 } 865 866 if (err >= 0) { 867 nfsdstats.io_read += err; 868 *count = err; 869 err = 0; 870 fsnotify_access(file->f_dentry); 871 } else 872 err = nfserrno(err); 873 out: 874 return err; 875 } 876 877 static inline int 878 nfsd_vfs_write(struct svc_rqst *rqstp, struct svc_fh *fhp, struct file *file, 879 loff_t offset, struct kvec *vec, int vlen, 880 unsigned long cnt, int *stablep) 881 { 882 struct svc_export *exp; 883 struct dentry *dentry; 884 struct inode *inode; 885 mm_segment_t oldfs; 886 int err = 0; 887 int stable = *stablep; 888 889 err = nfserr_perm; 890 891 #ifdef MSNFS 892 if ((fhp->fh_export->ex_flags & NFSEXP_MSNFS) && 893 (!lock_may_write(file->f_dentry->d_inode, offset, cnt))) 894 goto out; 895 #endif 896 897 dentry = file->f_dentry; 898 inode = dentry->d_inode; 899 exp = fhp->fh_export; 900 901 /* 902 * Request sync writes if 903 * - the sync export option has been set, or 904 * - the client requested O_SYNC behavior (NFSv3 feature). 905 * - The file system doesn't support fsync(). 906 * When gathered writes have been configured for this volume, 907 * flushing the data to disk is handled separately below. 908 */ 909 910 if (file->f_op->fsync == 0) {/* COMMIT3 cannot work */ 911 stable = 2; 912 *stablep = 2; /* FILE_SYNC */ 913 } 914 915 if (!EX_ISSYNC(exp)) 916 stable = 0; 917 if (stable && !EX_WGATHER(exp)) 918 file->f_flags |= O_SYNC; 919 920 /* Write the data. */ 921 oldfs = get_fs(); set_fs(KERNEL_DS); 922 err = vfs_writev(file, (struct iovec __user *)vec, vlen, &offset); 923 set_fs(oldfs); 924 if (err >= 0) { 925 nfsdstats.io_write += cnt; 926 fsnotify_modify(file->f_dentry); 927 } 928 929 /* clear setuid/setgid flag after write */ 930 if (err >= 0 && (inode->i_mode & (S_ISUID | S_ISGID))) { 931 struct iattr ia; 932 ia.ia_valid = ATTR_KILL_SUID | ATTR_KILL_SGID; 933 934 down(&inode->i_sem); 935 notify_change(dentry, &ia); 936 up(&inode->i_sem); 937 } 938 939 if (err >= 0 && stable) { 940 static ino_t last_ino; 941 static dev_t last_dev; 942 943 /* 944 * Gathered writes: If another process is currently 945 * writing to the file, there's a high chance 946 * this is another nfsd (triggered by a bulk write 947 * from a client's biod). Rather than syncing the 948 * file with each write request, we sleep for 10 msec. 949 * 950 * I don't know if this roughly approximates 951 * C. Juszak's idea of gathered writes, but it's a 952 * nice and simple solution (IMHO), and it seems to 953 * work:-) 954 */ 955 if (EX_WGATHER(exp)) { 956 if (atomic_read(&inode->i_writecount) > 1 957 || (last_ino == inode->i_ino && last_dev == inode->i_sb->s_dev)) { 958 dprintk("nfsd: write defer %d\n", current->pid); 959 msleep(10); 960 dprintk("nfsd: write resume %d\n", current->pid); 961 } 962 963 if (inode->i_state & I_DIRTY) { 964 dprintk("nfsd: write sync %d\n", current->pid); 965 nfsd_sync(file); 966 } 967 #if 0 968 wake_up(&inode->i_wait); 969 #endif 970 } 971 last_ino = inode->i_ino; 972 last_dev = inode->i_sb->s_dev; 973 } 974 975 dprintk("nfsd: write complete err=%d\n", err); 976 if (err >= 0) 977 err = 0; 978 else 979 err = nfserrno(err); 980 out: 981 return err; 982 } 983 984 /* 985 * Read data from a file. count must contain the requested read count 986 * on entry. On return, *count contains the number of bytes actually read. 987 * N.B. After this call fhp needs an fh_put 988 */ 989 int 990 nfsd_read(struct svc_rqst *rqstp, struct svc_fh *fhp, struct file *file, 991 loff_t offset, struct kvec *vec, int vlen, 992 unsigned long *count) 993 { 994 int err; 995 996 if (file) { 997 err = nfsd_permission(fhp->fh_export, fhp->fh_dentry, 998 MAY_READ|MAY_OWNER_OVERRIDE); 999 if (err) 1000 goto out; 1001 err = nfsd_vfs_read(rqstp, fhp, file, offset, vec, vlen, count); 1002 } else { 1003 err = nfsd_open(rqstp, fhp, S_IFREG, MAY_READ, &file); 1004 if (err) 1005 goto out; 1006 err = nfsd_vfs_read(rqstp, fhp, file, offset, vec, vlen, count); 1007 nfsd_close(file); 1008 } 1009 out: 1010 return err; 1011 } 1012 1013 /* 1014 * Write data to a file. 1015 * The stable flag requests synchronous writes. 1016 * N.B. After this call fhp needs an fh_put 1017 */ 1018 int 1019 nfsd_write(struct svc_rqst *rqstp, struct svc_fh *fhp, struct file *file, 1020 loff_t offset, struct kvec *vec, int vlen, unsigned long cnt, 1021 int *stablep) 1022 { 1023 int err = 0; 1024 1025 if (file) { 1026 err = nfsd_permission(fhp->fh_export, fhp->fh_dentry, 1027 MAY_WRITE|MAY_OWNER_OVERRIDE); 1028 if (err) 1029 goto out; 1030 err = nfsd_vfs_write(rqstp, fhp, file, offset, vec, vlen, cnt, 1031 stablep); 1032 } else { 1033 err = nfsd_open(rqstp, fhp, S_IFREG, MAY_WRITE, &file); 1034 if (err) 1035 goto out; 1036 1037 if (cnt) 1038 err = nfsd_vfs_write(rqstp, fhp, file, offset, vec, vlen, 1039 cnt, stablep); 1040 nfsd_close(file); 1041 } 1042 out: 1043 return err; 1044 } 1045 1046 #ifdef CONFIG_NFSD_V3 1047 /* 1048 * Commit all pending writes to stable storage. 1049 * Strictly speaking, we could sync just the indicated file region here, 1050 * but there's currently no way we can ask the VFS to do so. 1051 * 1052 * Unfortunately we cannot lock the file to make sure we return full WCC 1053 * data to the client, as locking happens lower down in the filesystem. 1054 */ 1055 int 1056 nfsd_commit(struct svc_rqst *rqstp, struct svc_fh *fhp, 1057 loff_t offset, unsigned long count) 1058 { 1059 struct file *file; 1060 int err; 1061 1062 if ((u64)count > ~(u64)offset) 1063 return nfserr_inval; 1064 1065 if ((err = nfsd_open(rqstp, fhp, S_IFREG, MAY_WRITE, &file)) != 0) 1066 return err; 1067 if (EX_ISSYNC(fhp->fh_export)) { 1068 if (file->f_op && file->f_op->fsync) { 1069 nfsd_sync(file); 1070 } else { 1071 err = nfserr_notsupp; 1072 } 1073 } 1074 1075 nfsd_close(file); 1076 return err; 1077 } 1078 #endif /* CONFIG_NFSD_V3 */ 1079 1080 /* 1081 * Create a file (regular, directory, device, fifo); UNIX sockets 1082 * not yet implemented. 1083 * If the response fh has been verified, the parent directory should 1084 * already be locked. Note that the parent directory is left locked. 1085 * 1086 * N.B. Every call to nfsd_create needs an fh_put for _both_ fhp and resfhp 1087 */ 1088 int 1089 nfsd_create(struct svc_rqst *rqstp, struct svc_fh *fhp, 1090 char *fname, int flen, struct iattr *iap, 1091 int type, dev_t rdev, struct svc_fh *resfhp) 1092 { 1093 struct dentry *dentry, *dchild = NULL; 1094 struct inode *dirp; 1095 int err; 1096 1097 err = nfserr_perm; 1098 if (!flen) 1099 goto out; 1100 err = nfserr_exist; 1101 if (isdotent(fname, flen)) 1102 goto out; 1103 1104 err = fh_verify(rqstp, fhp, S_IFDIR, MAY_CREATE); 1105 if (err) 1106 goto out; 1107 1108 dentry = fhp->fh_dentry; 1109 dirp = dentry->d_inode; 1110 1111 err = nfserr_notdir; 1112 if(!dirp->i_op || !dirp->i_op->lookup) 1113 goto out; 1114 /* 1115 * Check whether the response file handle has been verified yet. 1116 * If it has, the parent directory should already be locked. 1117 */ 1118 if (!resfhp->fh_dentry) { 1119 /* called from nfsd_proc_mkdir, or possibly nfsd3_proc_create */ 1120 fh_lock(fhp); 1121 dchild = lookup_one_len(fname, dentry, flen); 1122 err = PTR_ERR(dchild); 1123 if (IS_ERR(dchild)) 1124 goto out_nfserr; 1125 err = fh_compose(resfhp, fhp->fh_export, dchild, fhp); 1126 if (err) 1127 goto out; 1128 } else { 1129 /* called from nfsd_proc_create */ 1130 dchild = dget(resfhp->fh_dentry); 1131 if (!fhp->fh_locked) { 1132 /* not actually possible */ 1133 printk(KERN_ERR 1134 "nfsd_create: parent %s/%s not locked!\n", 1135 dentry->d_parent->d_name.name, 1136 dentry->d_name.name); 1137 err = -EIO; 1138 goto out; 1139 } 1140 } 1141 /* 1142 * Make sure the child dentry is still negative ... 1143 */ 1144 err = nfserr_exist; 1145 if (dchild->d_inode) { 1146 dprintk("nfsd_create: dentry %s/%s not negative!\n", 1147 dentry->d_name.name, dchild->d_name.name); 1148 goto out; 1149 } 1150 1151 if (!(iap->ia_valid & ATTR_MODE)) 1152 iap->ia_mode = 0; 1153 iap->ia_mode = (iap->ia_mode & S_IALLUGO) | type; 1154 1155 /* 1156 * Get the dir op function pointer. 1157 */ 1158 err = nfserr_perm; 1159 switch (type) { 1160 case S_IFREG: 1161 err = vfs_create(dirp, dchild, iap->ia_mode, NULL); 1162 break; 1163 case S_IFDIR: 1164 err = vfs_mkdir(dirp, dchild, iap->ia_mode); 1165 break; 1166 case S_IFCHR: 1167 case S_IFBLK: 1168 case S_IFIFO: 1169 case S_IFSOCK: 1170 err = vfs_mknod(dirp, dchild, iap->ia_mode, rdev); 1171 break; 1172 default: 1173 printk("nfsd: bad file type %o in nfsd_create\n", type); 1174 err = -EINVAL; 1175 } 1176 if (err < 0) 1177 goto out_nfserr; 1178 1179 if (EX_ISSYNC(fhp->fh_export)) { 1180 nfsd_sync_dir(dentry); 1181 write_inode_now(dchild->d_inode, 1); 1182 } 1183 1184 1185 /* Set file attributes. Mode has already been set and 1186 * setting uid/gid works only for root. Irix appears to 1187 * send along the gid when it tries to implement setgid 1188 * directories via NFS. 1189 */ 1190 err = 0; 1191 if ((iap->ia_valid &= ~(ATTR_UID|ATTR_GID|ATTR_MODE)) != 0) 1192 err = nfsd_setattr(rqstp, resfhp, iap, 0, (time_t)0); 1193 /* 1194 * Update the file handle to get the new inode info. 1195 */ 1196 if (!err) 1197 err = fh_update(resfhp); 1198 out: 1199 if (dchild && !IS_ERR(dchild)) 1200 dput(dchild); 1201 return err; 1202 1203 out_nfserr: 1204 err = nfserrno(err); 1205 goto out; 1206 } 1207 1208 #ifdef CONFIG_NFSD_V3 1209 /* 1210 * NFSv3 version of nfsd_create 1211 */ 1212 int 1213 nfsd_create_v3(struct svc_rqst *rqstp, struct svc_fh *fhp, 1214 char *fname, int flen, struct iattr *iap, 1215 struct svc_fh *resfhp, int createmode, u32 *verifier, 1216 int *truncp) 1217 { 1218 struct dentry *dentry, *dchild = NULL; 1219 struct inode *dirp; 1220 int err; 1221 __u32 v_mtime=0, v_atime=0; 1222 int v_mode=0; 1223 1224 err = nfserr_perm; 1225 if (!flen) 1226 goto out; 1227 err = nfserr_exist; 1228 if (isdotent(fname, flen)) 1229 goto out; 1230 if (!(iap->ia_valid & ATTR_MODE)) 1231 iap->ia_mode = 0; 1232 err = fh_verify(rqstp, fhp, S_IFDIR, MAY_CREATE); 1233 if (err) 1234 goto out; 1235 1236 dentry = fhp->fh_dentry; 1237 dirp = dentry->d_inode; 1238 1239 /* Get all the sanity checks out of the way before 1240 * we lock the parent. */ 1241 err = nfserr_notdir; 1242 if(!dirp->i_op || !dirp->i_op->lookup) 1243 goto out; 1244 fh_lock(fhp); 1245 1246 /* 1247 * Compose the response file handle. 1248 */ 1249 dchild = lookup_one_len(fname, dentry, flen); 1250 err = PTR_ERR(dchild); 1251 if (IS_ERR(dchild)) 1252 goto out_nfserr; 1253 1254 err = fh_compose(resfhp, fhp->fh_export, dchild, fhp); 1255 if (err) 1256 goto out; 1257 1258 if (createmode == NFS3_CREATE_EXCLUSIVE) { 1259 /* while the verifier would fit in mtime+atime, 1260 * solaris7 gets confused (bugid 4218508) if these have 1261 * the high bit set, so we use the mode as well 1262 */ 1263 v_mtime = verifier[0]&0x7fffffff; 1264 v_atime = verifier[1]&0x7fffffff; 1265 v_mode = S_IFREG 1266 | ((verifier[0]&0x80000000) >> (32-7)) /* u+x */ 1267 | ((verifier[1]&0x80000000) >> (32-9)) /* u+r */ 1268 ; 1269 } 1270 1271 if (dchild->d_inode) { 1272 err = 0; 1273 1274 switch (createmode) { 1275 case NFS3_CREATE_UNCHECKED: 1276 if (! S_ISREG(dchild->d_inode->i_mode)) 1277 err = nfserr_exist; 1278 else if (truncp) { 1279 /* in nfsv4, we need to treat this case a little 1280 * differently. we don't want to truncate the 1281 * file now; this would be wrong if the OPEN 1282 * fails for some other reason. furthermore, 1283 * if the size is nonzero, we should ignore it 1284 * according to spec! 1285 */ 1286 *truncp = (iap->ia_valid & ATTR_SIZE) && !iap->ia_size; 1287 } 1288 else { 1289 iap->ia_valid &= ATTR_SIZE; 1290 goto set_attr; 1291 } 1292 break; 1293 case NFS3_CREATE_EXCLUSIVE: 1294 if ( dchild->d_inode->i_mtime.tv_sec == v_mtime 1295 && dchild->d_inode->i_atime.tv_sec == v_atime 1296 && dchild->d_inode->i_mode == v_mode 1297 && dchild->d_inode->i_size == 0 ) 1298 break; 1299 /* fallthru */ 1300 case NFS3_CREATE_GUARDED: 1301 err = nfserr_exist; 1302 } 1303 goto out; 1304 } 1305 1306 err = vfs_create(dirp, dchild, iap->ia_mode, NULL); 1307 if (err < 0) 1308 goto out_nfserr; 1309 1310 if (EX_ISSYNC(fhp->fh_export)) { 1311 nfsd_sync_dir(dentry); 1312 /* setattr will sync the child (or not) */ 1313 } 1314 1315 /* 1316 * Update the filehandle to get the new inode info. 1317 */ 1318 err = fh_update(resfhp); 1319 if (err) 1320 goto out; 1321 1322 if (createmode == NFS3_CREATE_EXCLUSIVE) { 1323 /* Cram the verifier into atime/mtime/mode */ 1324 iap->ia_valid = ATTR_MTIME|ATTR_ATIME 1325 | ATTR_MTIME_SET|ATTR_ATIME_SET 1326 | ATTR_MODE; 1327 /* XXX someone who knows this better please fix it for nsec */ 1328 iap->ia_mtime.tv_sec = v_mtime; 1329 iap->ia_atime.tv_sec = v_atime; 1330 iap->ia_mtime.tv_nsec = 0; 1331 iap->ia_atime.tv_nsec = 0; 1332 iap->ia_mode = v_mode; 1333 } 1334 1335 /* Set file attributes. 1336 * Mode has already been set but we might need to reset it 1337 * for CREATE_EXCLUSIVE 1338 * Irix appears to send along the gid when it tries to 1339 * implement setgid directories via NFS. Clear out all that cruft. 1340 */ 1341 set_attr: 1342 if ((iap->ia_valid &= ~(ATTR_UID|ATTR_GID)) != 0) 1343 err = nfsd_setattr(rqstp, resfhp, iap, 0, (time_t)0); 1344 1345 out: 1346 fh_unlock(fhp); 1347 if (dchild && !IS_ERR(dchild)) 1348 dput(dchild); 1349 return err; 1350 1351 out_nfserr: 1352 err = nfserrno(err); 1353 goto out; 1354 } 1355 #endif /* CONFIG_NFSD_V3 */ 1356 1357 /* 1358 * Read a symlink. On entry, *lenp must contain the maximum path length that 1359 * fits into the buffer. On return, it contains the true length. 1360 * N.B. After this call fhp needs an fh_put 1361 */ 1362 int 1363 nfsd_readlink(struct svc_rqst *rqstp, struct svc_fh *fhp, char *buf, int *lenp) 1364 { 1365 struct dentry *dentry; 1366 struct inode *inode; 1367 mm_segment_t oldfs; 1368 int err; 1369 1370 err = fh_verify(rqstp, fhp, S_IFLNK, MAY_NOP); 1371 if (err) 1372 goto out; 1373 1374 dentry = fhp->fh_dentry; 1375 inode = dentry->d_inode; 1376 1377 err = nfserr_inval; 1378 if (!inode->i_op || !inode->i_op->readlink) 1379 goto out; 1380 1381 touch_atime(fhp->fh_export->ex_mnt, dentry); 1382 /* N.B. Why does this call need a get_fs()?? 1383 * Remove the set_fs and watch the fireworks:-) --okir 1384 */ 1385 1386 oldfs = get_fs(); set_fs(KERNEL_DS); 1387 err = inode->i_op->readlink(dentry, buf, *lenp); 1388 set_fs(oldfs); 1389 1390 if (err < 0) 1391 goto out_nfserr; 1392 *lenp = err; 1393 err = 0; 1394 out: 1395 return err; 1396 1397 out_nfserr: 1398 err = nfserrno(err); 1399 goto out; 1400 } 1401 1402 /* 1403 * Create a symlink and look up its inode 1404 * N.B. After this call _both_ fhp and resfhp need an fh_put 1405 */ 1406 int 1407 nfsd_symlink(struct svc_rqst *rqstp, struct svc_fh *fhp, 1408 char *fname, int flen, 1409 char *path, int plen, 1410 struct svc_fh *resfhp, 1411 struct iattr *iap) 1412 { 1413 struct dentry *dentry, *dnew; 1414 int err, cerr; 1415 umode_t mode; 1416 1417 err = nfserr_noent; 1418 if (!flen || !plen) 1419 goto out; 1420 err = nfserr_exist; 1421 if (isdotent(fname, flen)) 1422 goto out; 1423 1424 err = fh_verify(rqstp, fhp, S_IFDIR, MAY_CREATE); 1425 if (err) 1426 goto out; 1427 fh_lock(fhp); 1428 dentry = fhp->fh_dentry; 1429 dnew = lookup_one_len(fname, dentry, flen); 1430 err = PTR_ERR(dnew); 1431 if (IS_ERR(dnew)) 1432 goto out_nfserr; 1433 1434 mode = S_IALLUGO; 1435 /* Only the MODE ATTRibute is even vaguely meaningful */ 1436 if (iap && (iap->ia_valid & ATTR_MODE)) 1437 mode = iap->ia_mode & S_IALLUGO; 1438 1439 if (unlikely(path[plen] != 0)) { 1440 char *path_alloced = kmalloc(plen+1, GFP_KERNEL); 1441 if (path_alloced == NULL) 1442 err = -ENOMEM; 1443 else { 1444 strncpy(path_alloced, path, plen); 1445 path_alloced[plen] = 0; 1446 err = vfs_symlink(dentry->d_inode, dnew, path_alloced, mode); 1447 kfree(path_alloced); 1448 } 1449 } else 1450 err = vfs_symlink(dentry->d_inode, dnew, path, mode); 1451 1452 if (!err) { 1453 if (EX_ISSYNC(fhp->fh_export)) 1454 nfsd_sync_dir(dentry); 1455 } else 1456 err = nfserrno(err); 1457 fh_unlock(fhp); 1458 1459 cerr = fh_compose(resfhp, fhp->fh_export, dnew, fhp); 1460 dput(dnew); 1461 if (err==0) err = cerr; 1462 out: 1463 return err; 1464 1465 out_nfserr: 1466 err = nfserrno(err); 1467 goto out; 1468 } 1469 1470 /* 1471 * Create a hardlink 1472 * N.B. After this call _both_ ffhp and tfhp need an fh_put 1473 */ 1474 int 1475 nfsd_link(struct svc_rqst *rqstp, struct svc_fh *ffhp, 1476 char *name, int len, struct svc_fh *tfhp) 1477 { 1478 struct dentry *ddir, *dnew, *dold; 1479 struct inode *dirp, *dest; 1480 int err; 1481 1482 err = fh_verify(rqstp, ffhp, S_IFDIR, MAY_CREATE); 1483 if (err) 1484 goto out; 1485 err = fh_verify(rqstp, tfhp, -S_IFDIR, MAY_NOP); 1486 if (err) 1487 goto out; 1488 1489 err = nfserr_perm; 1490 if (!len) 1491 goto out; 1492 err = nfserr_exist; 1493 if (isdotent(name, len)) 1494 goto out; 1495 1496 fh_lock(ffhp); 1497 ddir = ffhp->fh_dentry; 1498 dirp = ddir->d_inode; 1499 1500 dnew = lookup_one_len(name, ddir, len); 1501 err = PTR_ERR(dnew); 1502 if (IS_ERR(dnew)) 1503 goto out_nfserr; 1504 1505 dold = tfhp->fh_dentry; 1506 dest = dold->d_inode; 1507 1508 err = vfs_link(dold, dirp, dnew); 1509 if (!err) { 1510 if (EX_ISSYNC(ffhp->fh_export)) { 1511 nfsd_sync_dir(ddir); 1512 write_inode_now(dest, 1); 1513 } 1514 } else { 1515 if (err == -EXDEV && rqstp->rq_vers == 2) 1516 err = nfserr_acces; 1517 else 1518 err = nfserrno(err); 1519 } 1520 1521 fh_unlock(ffhp); 1522 dput(dnew); 1523 out: 1524 return err; 1525 1526 out_nfserr: 1527 err = nfserrno(err); 1528 goto out; 1529 } 1530 1531 /* 1532 * Rename a file 1533 * N.B. After this call _both_ ffhp and tfhp need an fh_put 1534 */ 1535 int 1536 nfsd_rename(struct svc_rqst *rqstp, struct svc_fh *ffhp, char *fname, int flen, 1537 struct svc_fh *tfhp, char *tname, int tlen) 1538 { 1539 struct dentry *fdentry, *tdentry, *odentry, *ndentry, *trap; 1540 struct inode *fdir, *tdir; 1541 int err; 1542 1543 err = fh_verify(rqstp, ffhp, S_IFDIR, MAY_REMOVE); 1544 if (err) 1545 goto out; 1546 err = fh_verify(rqstp, tfhp, S_IFDIR, MAY_CREATE); 1547 if (err) 1548 goto out; 1549 1550 fdentry = ffhp->fh_dentry; 1551 fdir = fdentry->d_inode; 1552 1553 tdentry = tfhp->fh_dentry; 1554 tdir = tdentry->d_inode; 1555 1556 err = (rqstp->rq_vers == 2) ? nfserr_acces : nfserr_xdev; 1557 if (fdir->i_sb != tdir->i_sb) 1558 goto out; 1559 1560 err = nfserr_perm; 1561 if (!flen || isdotent(fname, flen) || !tlen || isdotent(tname, tlen)) 1562 goto out; 1563 1564 /* cannot use fh_lock as we need deadlock protective ordering 1565 * so do it by hand */ 1566 trap = lock_rename(tdentry, fdentry); 1567 ffhp->fh_locked = tfhp->fh_locked = 1; 1568 fill_pre_wcc(ffhp); 1569 fill_pre_wcc(tfhp); 1570 1571 odentry = lookup_one_len(fname, fdentry, flen); 1572 err = PTR_ERR(odentry); 1573 if (IS_ERR(odentry)) 1574 goto out_nfserr; 1575 1576 err = -ENOENT; 1577 if (!odentry->d_inode) 1578 goto out_dput_old; 1579 err = -EINVAL; 1580 if (odentry == trap) 1581 goto out_dput_old; 1582 1583 ndentry = lookup_one_len(tname, tdentry, tlen); 1584 err = PTR_ERR(ndentry); 1585 if (IS_ERR(ndentry)) 1586 goto out_dput_old; 1587 err = -ENOTEMPTY; 1588 if (ndentry == trap) 1589 goto out_dput_new; 1590 1591 #ifdef MSNFS 1592 if ((ffhp->fh_export->ex_flags & NFSEXP_MSNFS) && 1593 ((atomic_read(&odentry->d_count) > 1) 1594 || (atomic_read(&ndentry->d_count) > 1))) { 1595 err = nfserr_perm; 1596 } else 1597 #endif 1598 err = vfs_rename(fdir, odentry, tdir, ndentry); 1599 if (!err && EX_ISSYNC(tfhp->fh_export)) { 1600 nfsd_sync_dir(tdentry); 1601 nfsd_sync_dir(fdentry); 1602 } 1603 1604 out_dput_new: 1605 dput(ndentry); 1606 out_dput_old: 1607 dput(odentry); 1608 out_nfserr: 1609 if (err) 1610 err = nfserrno(err); 1611 1612 /* we cannot reply on fh_unlock on the two filehandles, 1613 * as that would do the wrong thing if the two directories 1614 * were the same, so again we do it by hand 1615 */ 1616 fill_post_wcc(ffhp); 1617 fill_post_wcc(tfhp); 1618 unlock_rename(tdentry, fdentry); 1619 ffhp->fh_locked = tfhp->fh_locked = 0; 1620 1621 out: 1622 return err; 1623 } 1624 1625 /* 1626 * Unlink a file or directory 1627 * N.B. After this call fhp needs an fh_put 1628 */ 1629 int 1630 nfsd_unlink(struct svc_rqst *rqstp, struct svc_fh *fhp, int type, 1631 char *fname, int flen) 1632 { 1633 struct dentry *dentry, *rdentry; 1634 struct inode *dirp; 1635 int err; 1636 1637 err = nfserr_acces; 1638 if (!flen || isdotent(fname, flen)) 1639 goto out; 1640 err = fh_verify(rqstp, fhp, S_IFDIR, MAY_REMOVE); 1641 if (err) 1642 goto out; 1643 1644 fh_lock(fhp); 1645 dentry = fhp->fh_dentry; 1646 dirp = dentry->d_inode; 1647 1648 rdentry = lookup_one_len(fname, dentry, flen); 1649 err = PTR_ERR(rdentry); 1650 if (IS_ERR(rdentry)) 1651 goto out_nfserr; 1652 1653 if (!rdentry->d_inode) { 1654 dput(rdentry); 1655 err = nfserr_noent; 1656 goto out; 1657 } 1658 1659 if (!type) 1660 type = rdentry->d_inode->i_mode & S_IFMT; 1661 1662 if (type != S_IFDIR) { /* It's UNLINK */ 1663 #ifdef MSNFS 1664 if ((fhp->fh_export->ex_flags & NFSEXP_MSNFS) && 1665 (atomic_read(&rdentry->d_count) > 1)) { 1666 err = nfserr_perm; 1667 } else 1668 #endif 1669 err = vfs_unlink(dirp, rdentry); 1670 } else { /* It's RMDIR */ 1671 err = vfs_rmdir(dirp, rdentry); 1672 } 1673 1674 dput(rdentry); 1675 1676 if (err) 1677 goto out_nfserr; 1678 if (EX_ISSYNC(fhp->fh_export)) 1679 nfsd_sync_dir(dentry); 1680 1681 out: 1682 return err; 1683 1684 out_nfserr: 1685 err = nfserrno(err); 1686 goto out; 1687 } 1688 1689 /* 1690 * Read entries from a directory. 1691 * The NFSv3/4 verifier we ignore for now. 1692 */ 1693 int 1694 nfsd_readdir(struct svc_rqst *rqstp, struct svc_fh *fhp, loff_t *offsetp, 1695 struct readdir_cd *cdp, encode_dent_fn func) 1696 { 1697 int err; 1698 struct file *file; 1699 loff_t offset = *offsetp; 1700 1701 err = nfsd_open(rqstp, fhp, S_IFDIR, MAY_READ, &file); 1702 if (err) 1703 goto out; 1704 1705 offset = vfs_llseek(file, offset, 0); 1706 if (offset < 0) { 1707 err = nfserrno((int)offset); 1708 goto out_close; 1709 } 1710 1711 /* 1712 * Read the directory entries. This silly loop is necessary because 1713 * readdir() is not guaranteed to fill up the entire buffer, but 1714 * may choose to do less. 1715 */ 1716 1717 do { 1718 cdp->err = nfserr_eof; /* will be cleared on successful read */ 1719 err = vfs_readdir(file, (filldir_t) func, cdp); 1720 } while (err >=0 && cdp->err == nfs_ok); 1721 if (err) 1722 err = nfserrno(err); 1723 else 1724 err = cdp->err; 1725 *offsetp = vfs_llseek(file, 0, 1); 1726 1727 if (err == nfserr_eof || err == nfserr_toosmall) 1728 err = nfs_ok; /* can still be found in ->err */ 1729 out_close: 1730 nfsd_close(file); 1731 out: 1732 return err; 1733 } 1734 1735 /* 1736 * Get file system stats 1737 * N.B. After this call fhp needs an fh_put 1738 */ 1739 int 1740 nfsd_statfs(struct svc_rqst *rqstp, struct svc_fh *fhp, struct kstatfs *stat) 1741 { 1742 int err = fh_verify(rqstp, fhp, 0, MAY_NOP); 1743 if (!err && vfs_statfs(fhp->fh_dentry->d_inode->i_sb,stat)) 1744 err = nfserr_io; 1745 return err; 1746 } 1747 1748 /* 1749 * Check for a user's access permissions to this inode. 1750 */ 1751 int 1752 nfsd_permission(struct svc_export *exp, struct dentry *dentry, int acc) 1753 { 1754 struct inode *inode = dentry->d_inode; 1755 int err; 1756 1757 if (acc == MAY_NOP) 1758 return 0; 1759 #if 0 1760 dprintk("nfsd: permission 0x%x%s%s%s%s%s%s%s mode 0%o%s%s%s\n", 1761 acc, 1762 (acc & MAY_READ)? " read" : "", 1763 (acc & MAY_WRITE)? " write" : "", 1764 (acc & MAY_EXEC)? " exec" : "", 1765 (acc & MAY_SATTR)? " sattr" : "", 1766 (acc & MAY_TRUNC)? " trunc" : "", 1767 (acc & MAY_LOCK)? " lock" : "", 1768 (acc & MAY_OWNER_OVERRIDE)? " owneroverride" : "", 1769 inode->i_mode, 1770 IS_IMMUTABLE(inode)? " immut" : "", 1771 IS_APPEND(inode)? " append" : "", 1772 IS_RDONLY(inode)? " ro" : ""); 1773 dprintk(" owner %d/%d user %d/%d\n", 1774 inode->i_uid, inode->i_gid, current->fsuid, current->fsgid); 1775 #endif 1776 1777 /* Normally we reject any write/sattr etc access on a read-only file 1778 * system. But if it is IRIX doing check on write-access for a 1779 * device special file, we ignore rofs. 1780 */ 1781 if (!(acc & MAY_LOCAL_ACCESS)) 1782 if (acc & (MAY_WRITE | MAY_SATTR | MAY_TRUNC)) { 1783 if (EX_RDONLY(exp) || IS_RDONLY(inode)) 1784 return nfserr_rofs; 1785 if (/* (acc & MAY_WRITE) && */ IS_IMMUTABLE(inode)) 1786 return nfserr_perm; 1787 } 1788 if ((acc & MAY_TRUNC) && IS_APPEND(inode)) 1789 return nfserr_perm; 1790 1791 if (acc & MAY_LOCK) { 1792 /* If we cannot rely on authentication in NLM requests, 1793 * just allow locks, otherwise require read permission, or 1794 * ownership 1795 */ 1796 if (exp->ex_flags & NFSEXP_NOAUTHNLM) 1797 return 0; 1798 else 1799 acc = MAY_READ | MAY_OWNER_OVERRIDE; 1800 } 1801 /* 1802 * The file owner always gets access permission for accesses that 1803 * would normally be checked at open time. This is to make 1804 * file access work even when the client has done a fchmod(fd, 0). 1805 * 1806 * However, `cp foo bar' should fail nevertheless when bar is 1807 * readonly. A sensible way to do this might be to reject all 1808 * attempts to truncate a read-only file, because a creat() call 1809 * always implies file truncation. 1810 * ... but this isn't really fair. A process may reasonably call 1811 * ftruncate on an open file descriptor on a file with perm 000. 1812 * We must trust the client to do permission checking - using "ACCESS" 1813 * with NFSv3. 1814 */ 1815 if ((acc & MAY_OWNER_OVERRIDE) && 1816 inode->i_uid == current->fsuid) 1817 return 0; 1818 1819 err = permission(inode, acc & (MAY_READ|MAY_WRITE|MAY_EXEC), NULL); 1820 1821 /* Allow read access to binaries even when mode 111 */ 1822 if (err == -EACCES && S_ISREG(inode->i_mode) && 1823 acc == (MAY_READ | MAY_OWNER_OVERRIDE)) 1824 err = permission(inode, MAY_EXEC, NULL); 1825 1826 return err? nfserrno(err) : 0; 1827 } 1828 1829 void 1830 nfsd_racache_shutdown(void) 1831 { 1832 if (!raparm_cache) 1833 return; 1834 dprintk("nfsd: freeing readahead buffers.\n"); 1835 kfree(raparml); 1836 raparm_cache = raparml = NULL; 1837 } 1838 /* 1839 * Initialize readahead param cache 1840 */ 1841 int 1842 nfsd_racache_init(int cache_size) 1843 { 1844 int i; 1845 1846 if (raparm_cache) 1847 return 0; 1848 raparml = kmalloc(sizeof(struct raparms) * cache_size, GFP_KERNEL); 1849 1850 if (raparml != NULL) { 1851 dprintk("nfsd: allocating %d readahead buffers.\n", 1852 cache_size); 1853 memset(raparml, 0, sizeof(struct raparms) * cache_size); 1854 for (i = 0; i < cache_size - 1; i++) { 1855 raparml[i].p_next = raparml + i + 1; 1856 } 1857 raparm_cache = raparml; 1858 } else { 1859 printk(KERN_WARNING 1860 "nfsd: Could not allocate memory read-ahead cache.\n"); 1861 return -ENOMEM; 1862 } 1863 nfsdstats.ra_size = cache_size; 1864 return 0; 1865 } 1866 1867 #if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) 1868 struct posix_acl * 1869 nfsd_get_posix_acl(struct svc_fh *fhp, int type) 1870 { 1871 struct inode *inode = fhp->fh_dentry->d_inode; 1872 char *name; 1873 void *value = NULL; 1874 ssize_t size; 1875 struct posix_acl *acl; 1876 1877 if (!IS_POSIXACL(inode) || !inode->i_op || !inode->i_op->getxattr) 1878 return ERR_PTR(-EOPNOTSUPP); 1879 switch(type) { 1880 case ACL_TYPE_ACCESS: 1881 name = POSIX_ACL_XATTR_ACCESS; 1882 break; 1883 case ACL_TYPE_DEFAULT: 1884 name = POSIX_ACL_XATTR_DEFAULT; 1885 break; 1886 default: 1887 return ERR_PTR(-EOPNOTSUPP); 1888 } 1889 1890 size = inode->i_op->getxattr(fhp->fh_dentry, name, NULL, 0); 1891 1892 if (size < 0) { 1893 acl = ERR_PTR(size); 1894 goto getout; 1895 } else if (size > 0) { 1896 value = kmalloc(size, GFP_KERNEL); 1897 if (!value) { 1898 acl = ERR_PTR(-ENOMEM); 1899 goto getout; 1900 } 1901 size = inode->i_op->getxattr(fhp->fh_dentry, name, value, size); 1902 if (size < 0) { 1903 acl = ERR_PTR(size); 1904 goto getout; 1905 } 1906 } 1907 acl = posix_acl_from_xattr(value, size); 1908 1909 getout: 1910 kfree(value); 1911 return acl; 1912 } 1913 1914 int 1915 nfsd_set_posix_acl(struct svc_fh *fhp, int type, struct posix_acl *acl) 1916 { 1917 struct inode *inode = fhp->fh_dentry->d_inode; 1918 char *name; 1919 void *value = NULL; 1920 size_t size; 1921 int error; 1922 1923 if (!IS_POSIXACL(inode) || !inode->i_op || 1924 !inode->i_op->setxattr || !inode->i_op->removexattr) 1925 return -EOPNOTSUPP; 1926 switch(type) { 1927 case ACL_TYPE_ACCESS: 1928 name = POSIX_ACL_XATTR_ACCESS; 1929 break; 1930 case ACL_TYPE_DEFAULT: 1931 name = POSIX_ACL_XATTR_DEFAULT; 1932 break; 1933 default: 1934 return -EOPNOTSUPP; 1935 } 1936 1937 if (acl && acl->a_count) { 1938 size = posix_acl_xattr_size(acl->a_count); 1939 value = kmalloc(size, GFP_KERNEL); 1940 if (!value) 1941 return -ENOMEM; 1942 size = posix_acl_to_xattr(acl, value, size); 1943 if (size < 0) { 1944 error = size; 1945 goto getout; 1946 } 1947 } else 1948 size = 0; 1949 1950 if (!fhp->fh_locked) 1951 fh_lock(fhp); /* unlocking is done automatically */ 1952 if (size) 1953 error = inode->i_op->setxattr(fhp->fh_dentry, name, 1954 value, size, 0); 1955 else { 1956 if (!S_ISDIR(inode->i_mode) && type == ACL_TYPE_DEFAULT) 1957 error = 0; 1958 else { 1959 error = inode->i_op->removexattr(fhp->fh_dentry, name); 1960 if (error == -ENODATA) 1961 error = 0; 1962 } 1963 } 1964 1965 getout: 1966 kfree(value); 1967 return error; 1968 } 1969 #endif /* defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) */ 1970