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 #include "fscache.h" 39 40 #define NFSDBG_FACILITY NFSDBG_FILE 41 42 static int nfs_file_open(struct inode *, struct file *); 43 static int nfs_file_release(struct inode *, struct file *); 44 static loff_t nfs_file_llseek(struct file *file, loff_t offset, int origin); 45 static int nfs_file_mmap(struct file *, struct vm_area_struct *); 46 static ssize_t nfs_file_splice_read(struct file *filp, loff_t *ppos, 47 struct pipe_inode_info *pipe, 48 size_t count, unsigned int flags); 49 static ssize_t nfs_file_read(struct kiocb *, const struct iovec *iov, 50 unsigned long nr_segs, loff_t pos); 51 static ssize_t nfs_file_write(struct kiocb *, const struct iovec *iov, 52 unsigned long nr_segs, loff_t pos); 53 static int nfs_file_flush(struct file *, fl_owner_t id); 54 static int nfs_file_fsync(struct file *, struct dentry *dentry, int datasync); 55 static int nfs_check_flags(int flags); 56 static int nfs_lock(struct file *filp, int cmd, struct file_lock *fl); 57 static int nfs_flock(struct file *filp, int cmd, struct file_lock *fl); 58 static int nfs_setlease(struct file *file, long arg, struct file_lock **fl); 59 60 static struct vm_operations_struct nfs_file_vm_ops; 61 62 const struct file_operations nfs_file_operations = { 63 .llseek = nfs_file_llseek, 64 .read = do_sync_read, 65 .write = do_sync_write, 66 .aio_read = nfs_file_read, 67 .aio_write = nfs_file_write, 68 .mmap = nfs_file_mmap, 69 .open = nfs_file_open, 70 .flush = nfs_file_flush, 71 .release = nfs_file_release, 72 .fsync = nfs_file_fsync, 73 .lock = nfs_lock, 74 .flock = nfs_flock, 75 .splice_read = nfs_file_splice_read, 76 .check_flags = nfs_check_flags, 77 .setlease = nfs_setlease, 78 }; 79 80 const struct inode_operations nfs_file_inode_operations = { 81 .permission = nfs_permission, 82 .getattr = nfs_getattr, 83 .setattr = nfs_setattr, 84 }; 85 86 #ifdef CONFIG_NFS_V3 87 const struct inode_operations nfs3_file_inode_operations = { 88 .permission = nfs_permission, 89 .getattr = nfs_getattr, 90 .setattr = nfs_setattr, 91 .listxattr = nfs3_listxattr, 92 .getxattr = nfs3_getxattr, 93 .setxattr = nfs3_setxattr, 94 .removexattr = nfs3_removexattr, 95 }; 96 #endif /* CONFIG_NFS_v3 */ 97 98 /* Hack for future NFS swap support */ 99 #ifndef IS_SWAPFILE 100 # define IS_SWAPFILE(inode) (0) 101 #endif 102 103 static int nfs_check_flags(int flags) 104 { 105 if ((flags & (O_APPEND | O_DIRECT)) == (O_APPEND | O_DIRECT)) 106 return -EINVAL; 107 108 return 0; 109 } 110 111 /* 112 * Open file 113 */ 114 static int 115 nfs_file_open(struct inode *inode, struct file *filp) 116 { 117 int res; 118 119 dprintk("NFS: open file(%s/%s)\n", 120 filp->f_path.dentry->d_parent->d_name.name, 121 filp->f_path.dentry->d_name.name); 122 123 res = nfs_check_flags(filp->f_flags); 124 if (res) 125 return res; 126 127 nfs_inc_stats(inode, NFSIOS_VFSOPEN); 128 res = nfs_open(inode, filp); 129 return res; 130 } 131 132 static int 133 nfs_file_release(struct inode *inode, struct file *filp) 134 { 135 struct dentry *dentry = filp->f_path.dentry; 136 137 dprintk("NFS: release(%s/%s)\n", 138 dentry->d_parent->d_name.name, 139 dentry->d_name.name); 140 141 nfs_inc_stats(inode, NFSIOS_VFSRELEASE); 142 return nfs_release(inode, filp); 143 } 144 145 /** 146 * nfs_revalidate_size - Revalidate the file size 147 * @inode - pointer to inode struct 148 * @file - pointer to struct file 149 * 150 * Revalidates the file length. This is basically a wrapper around 151 * nfs_revalidate_inode() that takes into account the fact that we may 152 * have cached writes (in which case we don't care about the server's 153 * idea of what the file length is), or O_DIRECT (in which case we 154 * shouldn't trust the cache). 155 */ 156 static int nfs_revalidate_file_size(struct inode *inode, struct file *filp) 157 { 158 struct nfs_server *server = NFS_SERVER(inode); 159 struct nfs_inode *nfsi = NFS_I(inode); 160 161 if (server->flags & NFS_MOUNT_NOAC) 162 goto force_reval; 163 if (filp->f_flags & O_DIRECT) 164 goto force_reval; 165 if (nfsi->npages != 0) 166 return 0; 167 if (!(nfsi->cache_validity & NFS_INO_REVAL_PAGECACHE) && !nfs_attribute_timeout(inode)) 168 return 0; 169 force_reval: 170 return __nfs_revalidate_inode(server, inode); 171 } 172 173 static loff_t nfs_file_llseek(struct file *filp, loff_t offset, int origin) 174 { 175 loff_t loff; 176 177 dprintk("NFS: llseek file(%s/%s, %lld, %d)\n", 178 filp->f_path.dentry->d_parent->d_name.name, 179 filp->f_path.dentry->d_name.name, 180 offset, origin); 181 182 /* origin == SEEK_END => we must revalidate the cached file length */ 183 if (origin == SEEK_END) { 184 struct inode *inode = filp->f_mapping->host; 185 186 int retval = nfs_revalidate_file_size(inode, filp); 187 if (retval < 0) 188 return (loff_t)retval; 189 190 spin_lock(&inode->i_lock); 191 loff = generic_file_llseek_unlocked(filp, offset, origin); 192 spin_unlock(&inode->i_lock); 193 } else 194 loff = generic_file_llseek_unlocked(filp, offset, origin); 195 return loff; 196 } 197 198 /* 199 * Helper for nfs_file_flush() and nfs_file_fsync() 200 * 201 * Notice that it clears the NFS_CONTEXT_ERROR_WRITE before synching to 202 * disk, but it retrieves and clears ctx->error after synching, despite 203 * the two being set at the same time in nfs_context_set_write_error(). 204 * This is because the former is used to notify the _next_ call to 205 * nfs_file_write() that a write error occured, and hence cause it to 206 * fall back to doing a synchronous write. 207 */ 208 static int nfs_do_fsync(struct nfs_open_context *ctx, struct inode *inode) 209 { 210 int have_error, status; 211 int ret = 0; 212 213 have_error = test_and_clear_bit(NFS_CONTEXT_ERROR_WRITE, &ctx->flags); 214 status = nfs_wb_all(inode); 215 have_error |= test_bit(NFS_CONTEXT_ERROR_WRITE, &ctx->flags); 216 if (have_error) 217 ret = xchg(&ctx->error, 0); 218 if (!ret) 219 ret = status; 220 return ret; 221 } 222 223 /* 224 * Flush all dirty pages, and check for write errors. 225 */ 226 static int 227 nfs_file_flush(struct file *file, fl_owner_t id) 228 { 229 struct nfs_open_context *ctx = nfs_file_open_context(file); 230 struct dentry *dentry = file->f_path.dentry; 231 struct inode *inode = dentry->d_inode; 232 233 dprintk("NFS: flush(%s/%s)\n", 234 dentry->d_parent->d_name.name, 235 dentry->d_name.name); 236 237 if ((file->f_mode & FMODE_WRITE) == 0) 238 return 0; 239 nfs_inc_stats(inode, NFSIOS_VFSFLUSH); 240 241 /* Flush writes to the server and return any errors */ 242 return nfs_do_fsync(ctx, inode); 243 } 244 245 static ssize_t 246 nfs_file_read(struct kiocb *iocb, const struct iovec *iov, 247 unsigned long nr_segs, loff_t pos) 248 { 249 struct dentry * dentry = iocb->ki_filp->f_path.dentry; 250 struct inode * inode = dentry->d_inode; 251 ssize_t result; 252 size_t count = iov_length(iov, nr_segs); 253 254 if (iocb->ki_filp->f_flags & O_DIRECT) 255 return nfs_file_direct_read(iocb, iov, nr_segs, pos); 256 257 dprintk("NFS: read(%s/%s, %lu@%lu)\n", 258 dentry->d_parent->d_name.name, dentry->d_name.name, 259 (unsigned long) count, (unsigned long) pos); 260 261 result = nfs_revalidate_mapping(inode, iocb->ki_filp->f_mapping); 262 nfs_add_stats(inode, NFSIOS_NORMALREADBYTES, count); 263 if (!result) 264 result = generic_file_aio_read(iocb, iov, nr_segs, pos); 265 return result; 266 } 267 268 static ssize_t 269 nfs_file_splice_read(struct file *filp, loff_t *ppos, 270 struct pipe_inode_info *pipe, size_t count, 271 unsigned int flags) 272 { 273 struct dentry *dentry = filp->f_path.dentry; 274 struct inode *inode = dentry->d_inode; 275 ssize_t res; 276 277 dprintk("NFS: splice_read(%s/%s, %lu@%Lu)\n", 278 dentry->d_parent->d_name.name, dentry->d_name.name, 279 (unsigned long) count, (unsigned long long) *ppos); 280 281 res = nfs_revalidate_mapping(inode, filp->f_mapping); 282 if (!res) 283 res = generic_file_splice_read(filp, ppos, pipe, count, flags); 284 return res; 285 } 286 287 static int 288 nfs_file_mmap(struct file * file, struct vm_area_struct * vma) 289 { 290 struct dentry *dentry = file->f_path.dentry; 291 struct inode *inode = dentry->d_inode; 292 int status; 293 294 dprintk("NFS: mmap(%s/%s)\n", 295 dentry->d_parent->d_name.name, dentry->d_name.name); 296 297 /* Note: generic_file_mmap() returns ENOSYS on nommu systems 298 * so we call that before revalidating the mapping 299 */ 300 status = generic_file_mmap(file, vma); 301 if (!status) { 302 vma->vm_ops = &nfs_file_vm_ops; 303 status = nfs_revalidate_mapping(inode, file->f_mapping); 304 } 305 return status; 306 } 307 308 /* 309 * Flush any dirty pages for this process, and check for write errors. 310 * The return status from this call provides a reliable indication of 311 * whether any write errors occurred for this process. 312 */ 313 static int 314 nfs_file_fsync(struct file *file, struct dentry *dentry, int datasync) 315 { 316 struct nfs_open_context *ctx = nfs_file_open_context(file); 317 struct inode *inode = dentry->d_inode; 318 319 dprintk("NFS: fsync file(%s/%s) datasync %d\n", 320 dentry->d_parent->d_name.name, dentry->d_name.name, 321 datasync); 322 323 nfs_inc_stats(inode, NFSIOS_VFSFSYNC); 324 return nfs_do_fsync(ctx, inode); 325 } 326 327 /* 328 * This does the "real" work of the write. We must allocate and lock the 329 * page to be sent back to the generic routine, which then copies the 330 * data from user space. 331 * 332 * If the writer ends up delaying the write, the writer needs to 333 * increment the page use counts until he is done with the page. 334 */ 335 static int nfs_write_begin(struct file *file, struct address_space *mapping, 336 loff_t pos, unsigned len, unsigned flags, 337 struct page **pagep, void **fsdata) 338 { 339 int ret; 340 pgoff_t index; 341 struct page *page; 342 index = pos >> PAGE_CACHE_SHIFT; 343 344 dfprintk(PAGECACHE, "NFS: write_begin(%s/%s(%ld), %u@%lld)\n", 345 file->f_path.dentry->d_parent->d_name.name, 346 file->f_path.dentry->d_name.name, 347 mapping->host->i_ino, len, (long long) pos); 348 349 /* 350 * Prevent starvation issues if someone is doing a consistency 351 * sync-to-disk 352 */ 353 ret = wait_on_bit(&NFS_I(mapping->host)->flags, NFS_INO_FLUSHING, 354 nfs_wait_bit_killable, TASK_KILLABLE); 355 if (ret) 356 return ret; 357 358 page = grab_cache_page_write_begin(mapping, index, flags); 359 if (!page) 360 return -ENOMEM; 361 *pagep = page; 362 363 ret = nfs_flush_incompatible(file, page); 364 if (ret) { 365 unlock_page(page); 366 page_cache_release(page); 367 } 368 return ret; 369 } 370 371 static int nfs_write_end(struct file *file, struct address_space *mapping, 372 loff_t pos, unsigned len, unsigned copied, 373 struct page *page, void *fsdata) 374 { 375 unsigned offset = pos & (PAGE_CACHE_SIZE - 1); 376 int status; 377 378 dfprintk(PAGECACHE, "NFS: write_end(%s/%s(%ld), %u@%lld)\n", 379 file->f_path.dentry->d_parent->d_name.name, 380 file->f_path.dentry->d_name.name, 381 mapping->host->i_ino, len, (long long) pos); 382 383 /* 384 * Zero any uninitialised parts of the page, and then mark the page 385 * as up to date if it turns out that we're extending the file. 386 */ 387 if (!PageUptodate(page)) { 388 unsigned pglen = nfs_page_length(page); 389 unsigned end = offset + len; 390 391 if (pglen == 0) { 392 zero_user_segments(page, 0, offset, 393 end, PAGE_CACHE_SIZE); 394 SetPageUptodate(page); 395 } else if (end >= pglen) { 396 zero_user_segment(page, end, PAGE_CACHE_SIZE); 397 if (offset == 0) 398 SetPageUptodate(page); 399 } else 400 zero_user_segment(page, pglen, PAGE_CACHE_SIZE); 401 } 402 403 status = nfs_updatepage(file, page, offset, copied); 404 405 unlock_page(page); 406 page_cache_release(page); 407 408 if (status < 0) 409 return status; 410 return copied; 411 } 412 413 /* 414 * Partially or wholly invalidate a page 415 * - Release the private state associated with a page if undergoing complete 416 * page invalidation 417 * - Called if either PG_private or PG_fscache is set on the page 418 * - Caller holds page lock 419 */ 420 static void nfs_invalidate_page(struct page *page, unsigned long offset) 421 { 422 dfprintk(PAGECACHE, "NFS: invalidate_page(%p, %lu)\n", page, offset); 423 424 if (offset != 0) 425 return; 426 /* Cancel any unstarted writes on this page */ 427 nfs_wb_page_cancel(page->mapping->host, page); 428 429 nfs_fscache_invalidate_page(page, page->mapping->host); 430 } 431 432 /* 433 * Attempt to release the private state associated with a page 434 * - Called if either PG_private or PG_fscache is set on the page 435 * - Caller holds page lock 436 * - Return true (may release page) or false (may not) 437 */ 438 static int nfs_release_page(struct page *page, gfp_t gfp) 439 { 440 dfprintk(PAGECACHE, "NFS: release_page(%p)\n", page); 441 442 /* If PagePrivate() is set, then the page is not freeable */ 443 if (PagePrivate(page)) 444 return 0; 445 return nfs_fscache_release_page(page, gfp); 446 } 447 448 /* 449 * Attempt to clear the private state associated with a page when an error 450 * occurs that requires the cached contents of an inode to be written back or 451 * destroyed 452 * - Called if either PG_private or fscache is set on the page 453 * - Caller holds page lock 454 * - Return 0 if successful, -error otherwise 455 */ 456 static int nfs_launder_page(struct page *page) 457 { 458 struct inode *inode = page->mapping->host; 459 struct nfs_inode *nfsi = NFS_I(inode); 460 461 dfprintk(PAGECACHE, "NFS: launder_page(%ld, %llu)\n", 462 inode->i_ino, (long long)page_offset(page)); 463 464 nfs_fscache_wait_on_page_write(nfsi, page); 465 return nfs_wb_page(inode, page); 466 } 467 468 const struct address_space_operations nfs_file_aops = { 469 .readpage = nfs_readpage, 470 .readpages = nfs_readpages, 471 .set_page_dirty = __set_page_dirty_nobuffers, 472 .writepage = nfs_writepage, 473 .writepages = nfs_writepages, 474 .write_begin = nfs_write_begin, 475 .write_end = nfs_write_end, 476 .invalidatepage = nfs_invalidate_page, 477 .releasepage = nfs_release_page, 478 .direct_IO = nfs_direct_IO, 479 .launder_page = nfs_launder_page, 480 }; 481 482 /* 483 * Notification that a PTE pointing to an NFS page is about to be made 484 * writable, implying that someone is about to modify the page through a 485 * shared-writable mapping 486 */ 487 static int nfs_vm_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf) 488 { 489 struct page *page = vmf->page; 490 struct file *filp = vma->vm_file; 491 struct dentry *dentry = filp->f_path.dentry; 492 unsigned pagelen; 493 int ret = -EINVAL; 494 struct address_space *mapping; 495 496 dfprintk(PAGECACHE, "NFS: vm_page_mkwrite(%s/%s(%ld), offset %lld)\n", 497 dentry->d_parent->d_name.name, dentry->d_name.name, 498 filp->f_mapping->host->i_ino, 499 (long long)page_offset(page)); 500 501 /* make sure the cache has finished storing the page */ 502 nfs_fscache_wait_on_page_write(NFS_I(dentry->d_inode), page); 503 504 lock_page(page); 505 mapping = page->mapping; 506 if (mapping != dentry->d_inode->i_mapping) 507 goto out_unlock; 508 509 ret = 0; 510 pagelen = nfs_page_length(page); 511 if (pagelen == 0) 512 goto out_unlock; 513 514 ret = nfs_flush_incompatible(filp, page); 515 if (ret != 0) 516 goto out_unlock; 517 518 ret = nfs_updatepage(filp, page, 0, pagelen); 519 out_unlock: 520 if (!ret) 521 return VM_FAULT_LOCKED; 522 unlock_page(page); 523 return VM_FAULT_SIGBUS; 524 } 525 526 static struct vm_operations_struct nfs_file_vm_ops = { 527 .fault = filemap_fault, 528 .page_mkwrite = nfs_vm_page_mkwrite, 529 }; 530 531 static int nfs_need_sync_write(struct file *filp, struct inode *inode) 532 { 533 struct nfs_open_context *ctx; 534 535 if (IS_SYNC(inode) || (filp->f_flags & O_SYNC)) 536 return 1; 537 ctx = nfs_file_open_context(filp); 538 if (test_bit(NFS_CONTEXT_ERROR_WRITE, &ctx->flags)) 539 return 1; 540 return 0; 541 } 542 543 static ssize_t nfs_file_write(struct kiocb *iocb, const struct iovec *iov, 544 unsigned long nr_segs, loff_t pos) 545 { 546 struct dentry * dentry = iocb->ki_filp->f_path.dentry; 547 struct inode * inode = dentry->d_inode; 548 ssize_t result; 549 size_t count = iov_length(iov, nr_segs); 550 551 if (iocb->ki_filp->f_flags & O_DIRECT) 552 return nfs_file_direct_write(iocb, iov, nr_segs, pos); 553 554 dprintk("NFS: write(%s/%s, %lu@%Ld)\n", 555 dentry->d_parent->d_name.name, dentry->d_name.name, 556 (unsigned long) count, (long long) pos); 557 558 result = -EBUSY; 559 if (IS_SWAPFILE(inode)) 560 goto out_swapfile; 561 /* 562 * O_APPEND implies that we must revalidate the file length. 563 */ 564 if (iocb->ki_filp->f_flags & O_APPEND) { 565 result = nfs_revalidate_file_size(inode, iocb->ki_filp); 566 if (result) 567 goto out; 568 } 569 570 result = count; 571 if (!count) 572 goto out; 573 574 nfs_add_stats(inode, NFSIOS_NORMALWRITTENBYTES, count); 575 result = generic_file_aio_write(iocb, iov, nr_segs, pos); 576 /* Return error values for O_SYNC and IS_SYNC() */ 577 if (result >= 0 && nfs_need_sync_write(iocb->ki_filp, inode)) { 578 int err = nfs_do_fsync(nfs_file_open_context(iocb->ki_filp), inode); 579 if (err < 0) 580 result = err; 581 } 582 out: 583 return result; 584 585 out_swapfile: 586 printk(KERN_INFO "NFS: attempt to write to active swap file!\n"); 587 goto out; 588 } 589 590 static int do_getlk(struct file *filp, int cmd, struct file_lock *fl) 591 { 592 struct inode *inode = filp->f_mapping->host; 593 int status = 0; 594 595 lock_kernel(); 596 /* Try local locking first */ 597 posix_test_lock(filp, fl); 598 if (fl->fl_type != F_UNLCK) { 599 /* found a conflict */ 600 goto out; 601 } 602 603 if (nfs_have_delegation(inode, FMODE_READ)) 604 goto out_noconflict; 605 606 if (NFS_SERVER(inode)->flags & NFS_MOUNT_NONLM) 607 goto out_noconflict; 608 609 status = NFS_PROTO(inode)->lock(filp, cmd, fl); 610 out: 611 unlock_kernel(); 612 return status; 613 out_noconflict: 614 fl->fl_type = F_UNLCK; 615 goto out; 616 } 617 618 static int do_vfs_lock(struct file *file, struct file_lock *fl) 619 { 620 int res = 0; 621 switch (fl->fl_flags & (FL_POSIX|FL_FLOCK)) { 622 case FL_POSIX: 623 res = posix_lock_file_wait(file, fl); 624 break; 625 case FL_FLOCK: 626 res = flock_lock_file_wait(file, fl); 627 break; 628 default: 629 BUG(); 630 } 631 if (res < 0) 632 dprintk(KERN_WARNING "%s: VFS is out of sync with lock manager" 633 " - error %d!\n", 634 __func__, res); 635 return res; 636 } 637 638 static int do_unlk(struct file *filp, int cmd, struct file_lock *fl) 639 { 640 struct inode *inode = filp->f_mapping->host; 641 int status; 642 643 /* 644 * Flush all pending writes before doing anything 645 * with locks.. 646 */ 647 nfs_sync_mapping(filp->f_mapping); 648 649 /* NOTE: special case 650 * If we're signalled while cleaning up locks on process exit, we 651 * still need to complete the unlock. 652 */ 653 lock_kernel(); 654 /* Use local locking if mounted with "-onolock" */ 655 if (!(NFS_SERVER(inode)->flags & NFS_MOUNT_NONLM)) 656 status = NFS_PROTO(inode)->lock(filp, cmd, fl); 657 else 658 status = do_vfs_lock(filp, fl); 659 unlock_kernel(); 660 return status; 661 } 662 663 static int do_setlk(struct file *filp, int cmd, struct file_lock *fl) 664 { 665 struct inode *inode = filp->f_mapping->host; 666 int status; 667 668 /* 669 * Flush all pending writes before doing anything 670 * with locks.. 671 */ 672 status = nfs_sync_mapping(filp->f_mapping); 673 if (status != 0) 674 goto out; 675 676 lock_kernel(); 677 /* Use local locking if mounted with "-onolock" */ 678 if (!(NFS_SERVER(inode)->flags & NFS_MOUNT_NONLM)) 679 status = NFS_PROTO(inode)->lock(filp, cmd, fl); 680 else 681 status = do_vfs_lock(filp, fl); 682 unlock_kernel(); 683 if (status < 0) 684 goto out; 685 /* 686 * Make sure we clear the cache whenever we try to get the lock. 687 * This makes locking act as a cache coherency point. 688 */ 689 nfs_sync_mapping(filp->f_mapping); 690 if (!nfs_have_delegation(inode, FMODE_READ)) 691 nfs_zap_caches(inode); 692 out: 693 return status; 694 } 695 696 /* 697 * Lock a (portion of) a file 698 */ 699 static int nfs_lock(struct file *filp, int cmd, struct file_lock *fl) 700 { 701 struct inode *inode = filp->f_mapping->host; 702 int ret = -ENOLCK; 703 704 dprintk("NFS: lock(%s/%s, t=%x, fl=%x, r=%lld:%lld)\n", 705 filp->f_path.dentry->d_parent->d_name.name, 706 filp->f_path.dentry->d_name.name, 707 fl->fl_type, fl->fl_flags, 708 (long long)fl->fl_start, (long long)fl->fl_end); 709 710 nfs_inc_stats(inode, NFSIOS_VFSLOCK); 711 712 /* No mandatory locks over NFS */ 713 if (__mandatory_lock(inode) && fl->fl_type != F_UNLCK) 714 goto out_err; 715 716 if (NFS_PROTO(inode)->lock_check_bounds != NULL) { 717 ret = NFS_PROTO(inode)->lock_check_bounds(fl); 718 if (ret < 0) 719 goto out_err; 720 } 721 722 if (IS_GETLK(cmd)) 723 ret = do_getlk(filp, cmd, fl); 724 else if (fl->fl_type == F_UNLCK) 725 ret = do_unlk(filp, cmd, fl); 726 else 727 ret = do_setlk(filp, cmd, fl); 728 out_err: 729 return ret; 730 } 731 732 /* 733 * Lock a (portion of) a file 734 */ 735 static int nfs_flock(struct file *filp, int cmd, struct file_lock *fl) 736 { 737 dprintk("NFS: flock(%s/%s, t=%x, fl=%x)\n", 738 filp->f_path.dentry->d_parent->d_name.name, 739 filp->f_path.dentry->d_name.name, 740 fl->fl_type, fl->fl_flags); 741 742 if (!(fl->fl_flags & FL_FLOCK)) 743 return -ENOLCK; 744 745 /* We're simulating flock() locks using posix locks on the server */ 746 fl->fl_owner = (fl_owner_t)filp; 747 fl->fl_start = 0; 748 fl->fl_end = OFFSET_MAX; 749 750 if (fl->fl_type == F_UNLCK) 751 return do_unlk(filp, cmd, fl); 752 return do_setlk(filp, cmd, fl); 753 } 754 755 /* 756 * There is no protocol support for leases, so we have no way to implement 757 * them correctly in the face of opens by other clients. 758 */ 759 static int nfs_setlease(struct file *file, long arg, struct file_lock **fl) 760 { 761 dprintk("NFS: setlease(%s/%s, arg=%ld)\n", 762 file->f_path.dentry->d_parent->d_name.name, 763 file->f_path.dentry->d_name.name, arg); 764 765 return -EINVAL; 766 } 767