1 /* 2 * linux/fs/nfs/file.c 3 * 4 * Copyright (C) 1992 Rick Sladkey 5 * 6 * Changes Copyright (C) 1994 by Florian La Roche 7 * - Do not copy data too often around in the kernel. 8 * - In nfs_file_read the return value of kmalloc wasn't checked. 9 * - Put in a better version of read look-ahead buffering. Original idea 10 * and implementation by Wai S Kok elekokws@ee.nus.sg. 11 * 12 * Expire cache on write to a file by Wai S Kok (Oct 1994). 13 * 14 * Total rewrite of read side for new NFS buffer cache.. Linus. 15 * 16 * nfs regular file handling functions 17 */ 18 19 #include <linux/time.h> 20 #include <linux/kernel.h> 21 #include <linux/errno.h> 22 #include <linux/fcntl.h> 23 #include <linux/stat.h> 24 #include <linux/nfs_fs.h> 25 #include <linux/nfs_mount.h> 26 #include <linux/mm.h> 27 #include <linux/slab.h> 28 #include <linux/pagemap.h> 29 #include <linux/smp_lock.h> 30 #include <linux/aio.h> 31 32 #include <asm/uaccess.h> 33 #include <asm/system.h> 34 35 #include "delegation.h" 36 #include "internal.h" 37 #include "iostat.h" 38 39 #define NFSDBG_FACILITY NFSDBG_FILE 40 41 static int nfs_file_open(struct inode *, struct file *); 42 static int nfs_file_release(struct inode *, struct file *); 43 static loff_t nfs_file_llseek(struct file *file, loff_t offset, int origin); 44 static int nfs_file_mmap(struct file *, struct vm_area_struct *); 45 static ssize_t nfs_file_splice_read(struct file *filp, loff_t *ppos, 46 struct pipe_inode_info *pipe, 47 size_t count, unsigned int flags); 48 static ssize_t nfs_file_read(struct kiocb *, const struct iovec *iov, 49 unsigned long nr_segs, loff_t pos); 50 static ssize_t nfs_file_write(struct kiocb *, const struct iovec *iov, 51 unsigned long nr_segs, loff_t pos); 52 static int nfs_file_flush(struct file *, fl_owner_t id); 53 static int nfs_file_fsync(struct file *, struct dentry *dentry, int datasync); 54 static int nfs_check_flags(int flags); 55 static int nfs_lock(struct file *filp, int cmd, struct file_lock *fl); 56 static int nfs_flock(struct file *filp, int cmd, struct file_lock *fl); 57 static int nfs_setlease(struct file *file, long arg, struct file_lock **fl); 58 59 static struct vm_operations_struct nfs_file_vm_ops; 60 61 const struct file_operations nfs_file_operations = { 62 .llseek = nfs_file_llseek, 63 .read = do_sync_read, 64 .write = do_sync_write, 65 .aio_read = nfs_file_read, 66 .aio_write = nfs_file_write, 67 .mmap = nfs_file_mmap, 68 .open = nfs_file_open, 69 .flush = nfs_file_flush, 70 .release = nfs_file_release, 71 .fsync = nfs_file_fsync, 72 .lock = nfs_lock, 73 .flock = nfs_flock, 74 .splice_read = nfs_file_splice_read, 75 .check_flags = nfs_check_flags, 76 .setlease = nfs_setlease, 77 }; 78 79 const struct inode_operations nfs_file_inode_operations = { 80 .permission = nfs_permission, 81 .getattr = nfs_getattr, 82 .setattr = nfs_setattr, 83 }; 84 85 #ifdef CONFIG_NFS_V3 86 const struct inode_operations nfs3_file_inode_operations = { 87 .permission = nfs_permission, 88 .getattr = nfs_getattr, 89 .setattr = nfs_setattr, 90 .listxattr = nfs3_listxattr, 91 .getxattr = nfs3_getxattr, 92 .setxattr = nfs3_setxattr, 93 .removexattr = nfs3_removexattr, 94 }; 95 #endif /* CONFIG_NFS_v3 */ 96 97 /* Hack for future NFS swap support */ 98 #ifndef IS_SWAPFILE 99 # define IS_SWAPFILE(inode) (0) 100 #endif 101 102 static int nfs_check_flags(int flags) 103 { 104 if ((flags & (O_APPEND | O_DIRECT)) == (O_APPEND | O_DIRECT)) 105 return -EINVAL; 106 107 return 0; 108 } 109 110 /* 111 * Open file 112 */ 113 static int 114 nfs_file_open(struct inode *inode, struct file *filp) 115 { 116 int res; 117 118 dprintk("NFS: open file(%s/%s)\n", 119 filp->f_path.dentry->d_parent->d_name.name, 120 filp->f_path.dentry->d_name.name); 121 122 res = nfs_check_flags(filp->f_flags); 123 if (res) 124 return res; 125 126 nfs_inc_stats(inode, NFSIOS_VFSOPEN); 127 res = nfs_open(inode, filp); 128 return res; 129 } 130 131 static int 132 nfs_file_release(struct inode *inode, struct file *filp) 133 { 134 struct dentry *dentry = filp->f_path.dentry; 135 136 dprintk("NFS: release(%s/%s)\n", 137 dentry->d_parent->d_name.name, 138 dentry->d_name.name); 139 140 nfs_inc_stats(inode, NFSIOS_VFSRELEASE); 141 return nfs_release(inode, filp); 142 } 143 144 /** 145 * nfs_revalidate_size - Revalidate the file size 146 * @inode - pointer to inode struct 147 * @file - pointer to struct file 148 * 149 * Revalidates the file length. This is basically a wrapper around 150 * nfs_revalidate_inode() that takes into account the fact that we may 151 * have cached writes (in which case we don't care about the server's 152 * idea of what the file length is), or O_DIRECT (in which case we 153 * shouldn't trust the cache). 154 */ 155 static int nfs_revalidate_file_size(struct inode *inode, struct file *filp) 156 { 157 struct nfs_server *server = NFS_SERVER(inode); 158 struct nfs_inode *nfsi = NFS_I(inode); 159 160 if (server->flags & NFS_MOUNT_NOAC) 161 goto force_reval; 162 if (filp->f_flags & O_DIRECT) 163 goto force_reval; 164 if (nfsi->npages != 0) 165 return 0; 166 if (!(nfsi->cache_validity & NFS_INO_REVAL_PAGECACHE) && !nfs_attribute_timeout(inode)) 167 return 0; 168 force_reval: 169 return __nfs_revalidate_inode(server, inode); 170 } 171 172 static loff_t nfs_file_llseek(struct file *filp, loff_t offset, int origin) 173 { 174 loff_t loff; 175 176 dprintk("NFS: llseek file(%s/%s, %lld, %d)\n", 177 filp->f_path.dentry->d_parent->d_name.name, 178 filp->f_path.dentry->d_name.name, 179 offset, origin); 180 181 /* origin == SEEK_END => we must revalidate the cached file length */ 182 if (origin == SEEK_END) { 183 struct inode *inode = filp->f_mapping->host; 184 185 int retval = nfs_revalidate_file_size(inode, filp); 186 if (retval < 0) 187 return (loff_t)retval; 188 189 spin_lock(&inode->i_lock); 190 loff = generic_file_llseek_unlocked(filp, offset, origin); 191 spin_unlock(&inode->i_lock); 192 } else 193 loff = generic_file_llseek_unlocked(filp, offset, origin); 194 return loff; 195 } 196 197 /* 198 * Helper for nfs_file_flush() and nfs_file_fsync() 199 * 200 * Notice that it clears the NFS_CONTEXT_ERROR_WRITE before synching to 201 * disk, but it retrieves and clears ctx->error after synching, despite 202 * the two being set at the same time in nfs_context_set_write_error(). 203 * This is because the former is used to notify the _next_ call to 204 * nfs_file_write() that a write error occured, and hence cause it to 205 * fall back to doing a synchronous write. 206 */ 207 static int nfs_do_fsync(struct nfs_open_context *ctx, struct inode *inode) 208 { 209 int have_error, status; 210 int ret = 0; 211 212 have_error = test_and_clear_bit(NFS_CONTEXT_ERROR_WRITE, &ctx->flags); 213 status = nfs_wb_all(inode); 214 have_error |= test_bit(NFS_CONTEXT_ERROR_WRITE, &ctx->flags); 215 if (have_error) 216 ret = xchg(&ctx->error, 0); 217 if (!ret) 218 ret = status; 219 return ret; 220 } 221 222 /* 223 * Flush all dirty pages, and check for write errors. 224 */ 225 static int 226 nfs_file_flush(struct file *file, fl_owner_t id) 227 { 228 struct nfs_open_context *ctx = nfs_file_open_context(file); 229 struct dentry *dentry = file->f_path.dentry; 230 struct inode *inode = dentry->d_inode; 231 232 dprintk("NFS: flush(%s/%s)\n", 233 dentry->d_parent->d_name.name, 234 dentry->d_name.name); 235 236 if ((file->f_mode & FMODE_WRITE) == 0) 237 return 0; 238 nfs_inc_stats(inode, NFSIOS_VFSFLUSH); 239 240 /* Flush writes to the server and return any errors */ 241 return nfs_do_fsync(ctx, inode); 242 } 243 244 static ssize_t 245 nfs_file_read(struct kiocb *iocb, const struct iovec *iov, 246 unsigned long nr_segs, loff_t pos) 247 { 248 struct dentry * dentry = iocb->ki_filp->f_path.dentry; 249 struct inode * inode = dentry->d_inode; 250 ssize_t result; 251 size_t count = iov_length(iov, nr_segs); 252 253 if (iocb->ki_filp->f_flags & O_DIRECT) 254 return nfs_file_direct_read(iocb, iov, nr_segs, pos); 255 256 dprintk("NFS: read(%s/%s, %lu@%lu)\n", 257 dentry->d_parent->d_name.name, dentry->d_name.name, 258 (unsigned long) count, (unsigned long) pos); 259 260 result = nfs_revalidate_mapping(inode, iocb->ki_filp->f_mapping); 261 nfs_add_stats(inode, NFSIOS_NORMALREADBYTES, count); 262 if (!result) 263 result = generic_file_aio_read(iocb, iov, nr_segs, pos); 264 return result; 265 } 266 267 static ssize_t 268 nfs_file_splice_read(struct file *filp, loff_t *ppos, 269 struct pipe_inode_info *pipe, size_t count, 270 unsigned int flags) 271 { 272 struct dentry *dentry = filp->f_path.dentry; 273 struct inode *inode = dentry->d_inode; 274 ssize_t res; 275 276 dprintk("NFS: splice_read(%s/%s, %lu@%Lu)\n", 277 dentry->d_parent->d_name.name, dentry->d_name.name, 278 (unsigned long) count, (unsigned long long) *ppos); 279 280 res = nfs_revalidate_mapping(inode, filp->f_mapping); 281 if (!res) 282 res = generic_file_splice_read(filp, ppos, pipe, count, flags); 283 return res; 284 } 285 286 static int 287 nfs_file_mmap(struct file * file, struct vm_area_struct * vma) 288 { 289 struct dentry *dentry = file->f_path.dentry; 290 struct inode *inode = dentry->d_inode; 291 int status; 292 293 dprintk("NFS: mmap(%s/%s)\n", 294 dentry->d_parent->d_name.name, dentry->d_name.name); 295 296 /* Note: generic_file_mmap() returns ENOSYS on nommu systems 297 * so we call that before revalidating the mapping 298 */ 299 status = generic_file_mmap(file, vma); 300 if (!status) { 301 vma->vm_ops = &nfs_file_vm_ops; 302 status = nfs_revalidate_mapping(inode, file->f_mapping); 303 } 304 return status; 305 } 306 307 /* 308 * Flush any dirty pages for this process, and check for write errors. 309 * The return status from this call provides a reliable indication of 310 * whether any write errors occurred for this process. 311 */ 312 static int 313 nfs_file_fsync(struct file *file, struct dentry *dentry, int datasync) 314 { 315 struct nfs_open_context *ctx = nfs_file_open_context(file); 316 struct inode *inode = dentry->d_inode; 317 318 dprintk("NFS: fsync file(%s/%s) datasync %d\n", 319 dentry->d_parent->d_name.name, dentry->d_name.name, 320 datasync); 321 322 nfs_inc_stats(inode, NFSIOS_VFSFSYNC); 323 return nfs_do_fsync(ctx, inode); 324 } 325 326 /* 327 * This does the "real" work of the write. We must allocate and lock the 328 * page to be sent back to the generic routine, which then copies the 329 * data from user space. 330 * 331 * If the writer ends up delaying the write, the writer needs to 332 * increment the page use counts until he is done with the page. 333 */ 334 static int nfs_write_begin(struct file *file, struct address_space *mapping, 335 loff_t pos, unsigned len, unsigned flags, 336 struct page **pagep, void **fsdata) 337 { 338 int ret; 339 pgoff_t index; 340 struct page *page; 341 index = pos >> PAGE_CACHE_SHIFT; 342 343 dfprintk(PAGECACHE, "NFS: write_begin(%s/%s(%ld), %u@%lld)\n", 344 file->f_path.dentry->d_parent->d_name.name, 345 file->f_path.dentry->d_name.name, 346 mapping->host->i_ino, len, (long long) pos); 347 348 /* 349 * Prevent starvation issues if someone is doing a consistency 350 * sync-to-disk 351 */ 352 ret = wait_on_bit(&NFS_I(mapping->host)->flags, NFS_INO_FLUSHING, 353 nfs_wait_bit_killable, TASK_KILLABLE); 354 if (ret) 355 return ret; 356 357 page = grab_cache_page_write_begin(mapping, index, flags); 358 if (!page) 359 return -ENOMEM; 360 *pagep = page; 361 362 ret = nfs_flush_incompatible(file, page); 363 if (ret) { 364 unlock_page(page); 365 page_cache_release(page); 366 } 367 return ret; 368 } 369 370 static int nfs_write_end(struct file *file, struct address_space *mapping, 371 loff_t pos, unsigned len, unsigned copied, 372 struct page *page, void *fsdata) 373 { 374 unsigned offset = pos & (PAGE_CACHE_SIZE - 1); 375 int status; 376 377 dfprintk(PAGECACHE, "NFS: write_end(%s/%s(%ld), %u@%lld)\n", 378 file->f_path.dentry->d_parent->d_name.name, 379 file->f_path.dentry->d_name.name, 380 mapping->host->i_ino, len, (long long) pos); 381 382 /* 383 * Zero any uninitialised parts of the page, and then mark the page 384 * as up to date if it turns out that we're extending the file. 385 */ 386 if (!PageUptodate(page)) { 387 unsigned pglen = nfs_page_length(page); 388 unsigned end = offset + len; 389 390 if (pglen == 0) { 391 zero_user_segments(page, 0, offset, 392 end, PAGE_CACHE_SIZE); 393 SetPageUptodate(page); 394 } else if (end >= pglen) { 395 zero_user_segment(page, end, PAGE_CACHE_SIZE); 396 if (offset == 0) 397 SetPageUptodate(page); 398 } else 399 zero_user_segment(page, pglen, PAGE_CACHE_SIZE); 400 } 401 402 status = nfs_updatepage(file, page, offset, copied); 403 404 unlock_page(page); 405 page_cache_release(page); 406 407 if (status < 0) 408 return status; 409 return copied; 410 } 411 412 static void nfs_invalidate_page(struct page *page, unsigned long offset) 413 { 414 dfprintk(PAGECACHE, "NFS: invalidate_page(%p, %lu)\n", page, offset); 415 416 if (offset != 0) 417 return; 418 /* Cancel any unstarted writes on this page */ 419 nfs_wb_page_cancel(page->mapping->host, page); 420 } 421 422 static int nfs_release_page(struct page *page, gfp_t gfp) 423 { 424 dfprintk(PAGECACHE, "NFS: release_page(%p)\n", page); 425 426 /* If PagePrivate() is set, then the page is not freeable */ 427 return 0; 428 } 429 430 static int nfs_launder_page(struct page *page) 431 { 432 struct inode *inode = page->mapping->host; 433 434 dfprintk(PAGECACHE, "NFS: launder_page(%ld, %llu)\n", 435 inode->i_ino, (long long)page_offset(page)); 436 437 return nfs_wb_page(inode, page); 438 } 439 440 const struct address_space_operations nfs_file_aops = { 441 .readpage = nfs_readpage, 442 .readpages = nfs_readpages, 443 .set_page_dirty = __set_page_dirty_nobuffers, 444 .writepage = nfs_writepage, 445 .writepages = nfs_writepages, 446 .write_begin = nfs_write_begin, 447 .write_end = nfs_write_end, 448 .invalidatepage = nfs_invalidate_page, 449 .releasepage = nfs_release_page, 450 .direct_IO = nfs_direct_IO, 451 .launder_page = nfs_launder_page, 452 }; 453 454 static int nfs_vm_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf) 455 { 456 struct page *page = vmf->page; 457 struct file *filp = vma->vm_file; 458 struct dentry *dentry = filp->f_path.dentry; 459 unsigned pagelen; 460 int ret = -EINVAL; 461 struct address_space *mapping; 462 463 dfprintk(PAGECACHE, "NFS: vm_page_mkwrite(%s/%s(%ld), offset %lld)\n", 464 dentry->d_parent->d_name.name, dentry->d_name.name, 465 filp->f_mapping->host->i_ino, 466 (long long)page_offset(page)); 467 468 lock_page(page); 469 mapping = page->mapping; 470 if (mapping != dentry->d_inode->i_mapping) 471 goto out_unlock; 472 473 ret = 0; 474 pagelen = nfs_page_length(page); 475 if (pagelen == 0) 476 goto out_unlock; 477 478 ret = nfs_flush_incompatible(filp, page); 479 if (ret != 0) 480 goto out_unlock; 481 482 ret = nfs_updatepage(filp, page, 0, pagelen); 483 if (ret == 0) 484 ret = pagelen; 485 out_unlock: 486 unlock_page(page); 487 if (ret) 488 ret = VM_FAULT_SIGBUS; 489 return ret; 490 } 491 492 static struct vm_operations_struct nfs_file_vm_ops = { 493 .fault = filemap_fault, 494 .page_mkwrite = nfs_vm_page_mkwrite, 495 }; 496 497 static int nfs_need_sync_write(struct file *filp, struct inode *inode) 498 { 499 struct nfs_open_context *ctx; 500 501 if (IS_SYNC(inode) || (filp->f_flags & O_SYNC)) 502 return 1; 503 ctx = nfs_file_open_context(filp); 504 if (test_bit(NFS_CONTEXT_ERROR_WRITE, &ctx->flags)) 505 return 1; 506 return 0; 507 } 508 509 static ssize_t nfs_file_write(struct kiocb *iocb, const struct iovec *iov, 510 unsigned long nr_segs, loff_t pos) 511 { 512 struct dentry * dentry = iocb->ki_filp->f_path.dentry; 513 struct inode * inode = dentry->d_inode; 514 ssize_t result; 515 size_t count = iov_length(iov, nr_segs); 516 517 if (iocb->ki_filp->f_flags & O_DIRECT) 518 return nfs_file_direct_write(iocb, iov, nr_segs, pos); 519 520 dprintk("NFS: write(%s/%s, %lu@%Ld)\n", 521 dentry->d_parent->d_name.name, dentry->d_name.name, 522 (unsigned long) count, (long long) pos); 523 524 result = -EBUSY; 525 if (IS_SWAPFILE(inode)) 526 goto out_swapfile; 527 /* 528 * O_APPEND implies that we must revalidate the file length. 529 */ 530 if (iocb->ki_filp->f_flags & O_APPEND) { 531 result = nfs_revalidate_file_size(inode, iocb->ki_filp); 532 if (result) 533 goto out; 534 } 535 536 result = count; 537 if (!count) 538 goto out; 539 540 nfs_add_stats(inode, NFSIOS_NORMALWRITTENBYTES, count); 541 result = generic_file_aio_write(iocb, iov, nr_segs, pos); 542 /* Return error values for O_SYNC and IS_SYNC() */ 543 if (result >= 0 && nfs_need_sync_write(iocb->ki_filp, inode)) { 544 int err = nfs_do_fsync(nfs_file_open_context(iocb->ki_filp), inode); 545 if (err < 0) 546 result = err; 547 } 548 out: 549 return result; 550 551 out_swapfile: 552 printk(KERN_INFO "NFS: attempt to write to active swap file!\n"); 553 goto out; 554 } 555 556 static int do_getlk(struct file *filp, int cmd, struct file_lock *fl) 557 { 558 struct inode *inode = filp->f_mapping->host; 559 int status = 0; 560 561 lock_kernel(); 562 /* Try local locking first */ 563 posix_test_lock(filp, fl); 564 if (fl->fl_type != F_UNLCK) { 565 /* found a conflict */ 566 goto out; 567 } 568 569 if (nfs_have_delegation(inode, FMODE_READ)) 570 goto out_noconflict; 571 572 if (NFS_SERVER(inode)->flags & NFS_MOUNT_NONLM) 573 goto out_noconflict; 574 575 status = NFS_PROTO(inode)->lock(filp, cmd, fl); 576 out: 577 unlock_kernel(); 578 return status; 579 out_noconflict: 580 fl->fl_type = F_UNLCK; 581 goto out; 582 } 583 584 static int do_vfs_lock(struct file *file, struct file_lock *fl) 585 { 586 int res = 0; 587 switch (fl->fl_flags & (FL_POSIX|FL_FLOCK)) { 588 case FL_POSIX: 589 res = posix_lock_file_wait(file, fl); 590 break; 591 case FL_FLOCK: 592 res = flock_lock_file_wait(file, fl); 593 break; 594 default: 595 BUG(); 596 } 597 if (res < 0) 598 dprintk(KERN_WARNING "%s: VFS is out of sync with lock manager" 599 " - error %d!\n", 600 __func__, res); 601 return res; 602 } 603 604 static int do_unlk(struct file *filp, int cmd, struct file_lock *fl) 605 { 606 struct inode *inode = filp->f_mapping->host; 607 int status; 608 609 /* 610 * Flush all pending writes before doing anything 611 * with locks.. 612 */ 613 nfs_sync_mapping(filp->f_mapping); 614 615 /* NOTE: special case 616 * If we're signalled while cleaning up locks on process exit, we 617 * still need to complete the unlock. 618 */ 619 lock_kernel(); 620 /* Use local locking if mounted with "-onolock" */ 621 if (!(NFS_SERVER(inode)->flags & NFS_MOUNT_NONLM)) 622 status = NFS_PROTO(inode)->lock(filp, cmd, fl); 623 else 624 status = do_vfs_lock(filp, fl); 625 unlock_kernel(); 626 return status; 627 } 628 629 static int do_setlk(struct file *filp, int cmd, struct file_lock *fl) 630 { 631 struct inode *inode = filp->f_mapping->host; 632 int status; 633 634 /* 635 * Flush all pending writes before doing anything 636 * with locks.. 637 */ 638 status = nfs_sync_mapping(filp->f_mapping); 639 if (status != 0) 640 goto out; 641 642 lock_kernel(); 643 /* Use local locking if mounted with "-onolock" */ 644 if (!(NFS_SERVER(inode)->flags & NFS_MOUNT_NONLM)) 645 status = NFS_PROTO(inode)->lock(filp, cmd, fl); 646 else 647 status = do_vfs_lock(filp, fl); 648 unlock_kernel(); 649 if (status < 0) 650 goto out; 651 /* 652 * Make sure we clear the cache whenever we try to get the lock. 653 * This makes locking act as a cache coherency point. 654 */ 655 nfs_sync_mapping(filp->f_mapping); 656 if (!nfs_have_delegation(inode, FMODE_READ)) 657 nfs_zap_caches(inode); 658 out: 659 return status; 660 } 661 662 /* 663 * Lock a (portion of) a file 664 */ 665 static int nfs_lock(struct file *filp, int cmd, struct file_lock *fl) 666 { 667 struct inode *inode = filp->f_mapping->host; 668 int ret = -ENOLCK; 669 670 dprintk("NFS: lock(%s/%s, t=%x, fl=%x, r=%lld:%lld)\n", 671 filp->f_path.dentry->d_parent->d_name.name, 672 filp->f_path.dentry->d_name.name, 673 fl->fl_type, fl->fl_flags, 674 (long long)fl->fl_start, (long long)fl->fl_end); 675 676 nfs_inc_stats(inode, NFSIOS_VFSLOCK); 677 678 /* No mandatory locks over NFS */ 679 if (__mandatory_lock(inode) && fl->fl_type != F_UNLCK) 680 goto out_err; 681 682 if (NFS_PROTO(inode)->lock_check_bounds != NULL) { 683 ret = NFS_PROTO(inode)->lock_check_bounds(fl); 684 if (ret < 0) 685 goto out_err; 686 } 687 688 if (IS_GETLK(cmd)) 689 ret = do_getlk(filp, cmd, fl); 690 else if (fl->fl_type == F_UNLCK) 691 ret = do_unlk(filp, cmd, fl); 692 else 693 ret = do_setlk(filp, cmd, fl); 694 out_err: 695 return ret; 696 } 697 698 /* 699 * Lock a (portion of) a file 700 */ 701 static int nfs_flock(struct file *filp, int cmd, struct file_lock *fl) 702 { 703 dprintk("NFS: flock(%s/%s, t=%x, fl=%x)\n", 704 filp->f_path.dentry->d_parent->d_name.name, 705 filp->f_path.dentry->d_name.name, 706 fl->fl_type, fl->fl_flags); 707 708 if (!(fl->fl_flags & FL_FLOCK)) 709 return -ENOLCK; 710 711 /* We're simulating flock() locks using posix locks on the server */ 712 fl->fl_owner = (fl_owner_t)filp; 713 fl->fl_start = 0; 714 fl->fl_end = OFFSET_MAX; 715 716 if (fl->fl_type == F_UNLCK) 717 return do_unlk(filp, cmd, fl); 718 return do_setlk(filp, cmd, fl); 719 } 720 721 /* 722 * There is no protocol support for leases, so we have no way to implement 723 * them correctly in the face of opens by other clients. 724 */ 725 static int nfs_setlease(struct file *file, long arg, struct file_lock **fl) 726 { 727 dprintk("NFS: setlease(%s/%s, arg=%ld)\n", 728 file->f_path.dentry->d_parent->d_name.name, 729 file->f_path.dentry->d_name.name, arg); 730 731 return -EINVAL; 732 } 733