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