1 /* 2 * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. 3 * Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved. 4 * 5 * This copyrighted material is made available to anyone wishing to use, 6 * modify, copy, or redistribute it subject to the terms and conditions 7 * of the GNU General Public License version 2. 8 */ 9 10 #include <linux/slab.h> 11 #include <linux/spinlock.h> 12 #include <linux/completion.h> 13 #include <linux/buffer_head.h> 14 #include <linux/pagemap.h> 15 #include <linux/uio.h> 16 #include <linux/blkdev.h> 17 #include <linux/mm.h> 18 #include <linux/mount.h> 19 #include <linux/fs.h> 20 #include <linux/gfs2_ondisk.h> 21 #include <linux/ext2_fs.h> 22 #include <linux/crc32.h> 23 #include <linux/writeback.h> 24 #include <asm/uaccess.h> 25 #include <linux/dlm.h> 26 #include <linux/dlm_plock.h> 27 28 #include "gfs2.h" 29 #include "incore.h" 30 #include "bmap.h" 31 #include "dir.h" 32 #include "glock.h" 33 #include "glops.h" 34 #include "inode.h" 35 #include "log.h" 36 #include "meta_io.h" 37 #include "quota.h" 38 #include "rgrp.h" 39 #include "trans.h" 40 #include "util.h" 41 42 /** 43 * gfs2_llseek - seek to a location in a file 44 * @file: the file 45 * @offset: the offset 46 * @origin: Where to seek from (SEEK_SET, SEEK_CUR, or SEEK_END) 47 * 48 * SEEK_END requires the glock for the file because it references the 49 * file's size. 50 * 51 * Returns: The new offset, or errno 52 */ 53 54 static loff_t gfs2_llseek(struct file *file, loff_t offset, int origin) 55 { 56 struct gfs2_inode *ip = GFS2_I(file->f_mapping->host); 57 struct gfs2_holder i_gh; 58 loff_t error; 59 60 if (origin == 2) { 61 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, 62 &i_gh); 63 if (!error) { 64 error = generic_file_llseek_unlocked(file, offset, origin); 65 gfs2_glock_dq_uninit(&i_gh); 66 } 67 } else 68 error = generic_file_llseek_unlocked(file, offset, origin); 69 70 return error; 71 } 72 73 /** 74 * gfs2_readdir - Read directory entries from a directory 75 * @file: The directory to read from 76 * @dirent: Buffer for dirents 77 * @filldir: Function used to do the copying 78 * 79 * Returns: errno 80 */ 81 82 static int gfs2_readdir(struct file *file, void *dirent, filldir_t filldir) 83 { 84 struct inode *dir = file->f_mapping->host; 85 struct gfs2_inode *dip = GFS2_I(dir); 86 struct gfs2_holder d_gh; 87 u64 offset = file->f_pos; 88 int error; 89 90 gfs2_holder_init(dip->i_gl, LM_ST_SHARED, 0, &d_gh); 91 error = gfs2_glock_nq(&d_gh); 92 if (error) { 93 gfs2_holder_uninit(&d_gh); 94 return error; 95 } 96 97 error = gfs2_dir_read(dir, &offset, dirent, filldir); 98 99 gfs2_glock_dq_uninit(&d_gh); 100 101 file->f_pos = offset; 102 103 return error; 104 } 105 106 /** 107 * fsflags_cvt 108 * @table: A table of 32 u32 flags 109 * @val: a 32 bit value to convert 110 * 111 * This function can be used to convert between fsflags values and 112 * GFS2's own flags values. 113 * 114 * Returns: the converted flags 115 */ 116 static u32 fsflags_cvt(const u32 *table, u32 val) 117 { 118 u32 res = 0; 119 while(val) { 120 if (val & 1) 121 res |= *table; 122 table++; 123 val >>= 1; 124 } 125 return res; 126 } 127 128 static const u32 fsflags_to_gfs2[32] = { 129 [3] = GFS2_DIF_SYNC, 130 [4] = GFS2_DIF_IMMUTABLE, 131 [5] = GFS2_DIF_APPENDONLY, 132 [7] = GFS2_DIF_NOATIME, 133 [12] = GFS2_DIF_EXHASH, 134 [14] = GFS2_DIF_INHERIT_JDATA, 135 }; 136 137 static const u32 gfs2_to_fsflags[32] = { 138 [gfs2fl_Sync] = FS_SYNC_FL, 139 [gfs2fl_Immutable] = FS_IMMUTABLE_FL, 140 [gfs2fl_AppendOnly] = FS_APPEND_FL, 141 [gfs2fl_NoAtime] = FS_NOATIME_FL, 142 [gfs2fl_ExHash] = FS_INDEX_FL, 143 [gfs2fl_InheritJdata] = FS_JOURNAL_DATA_FL, 144 }; 145 146 static int gfs2_get_flags(struct file *filp, u32 __user *ptr) 147 { 148 struct inode *inode = filp->f_path.dentry->d_inode; 149 struct gfs2_inode *ip = GFS2_I(inode); 150 struct gfs2_holder gh; 151 int error; 152 u32 fsflags; 153 154 gfs2_holder_init(ip->i_gl, LM_ST_SHARED, 0, &gh); 155 error = gfs2_glock_nq(&gh); 156 if (error) 157 return error; 158 159 fsflags = fsflags_cvt(gfs2_to_fsflags, ip->i_diskflags); 160 if (!S_ISDIR(inode->i_mode) && ip->i_diskflags & GFS2_DIF_JDATA) 161 fsflags |= FS_JOURNAL_DATA_FL; 162 if (put_user(fsflags, ptr)) 163 error = -EFAULT; 164 165 gfs2_glock_dq(&gh); 166 gfs2_holder_uninit(&gh); 167 return error; 168 } 169 170 void gfs2_set_inode_flags(struct inode *inode) 171 { 172 struct gfs2_inode *ip = GFS2_I(inode); 173 unsigned int flags = inode->i_flags; 174 175 flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC); 176 if (ip->i_diskflags & GFS2_DIF_IMMUTABLE) 177 flags |= S_IMMUTABLE; 178 if (ip->i_diskflags & GFS2_DIF_APPENDONLY) 179 flags |= S_APPEND; 180 if (ip->i_diskflags & GFS2_DIF_NOATIME) 181 flags |= S_NOATIME; 182 if (ip->i_diskflags & GFS2_DIF_SYNC) 183 flags |= S_SYNC; 184 inode->i_flags = flags; 185 } 186 187 /* Flags that can be set by user space */ 188 #define GFS2_FLAGS_USER_SET (GFS2_DIF_JDATA| \ 189 GFS2_DIF_IMMUTABLE| \ 190 GFS2_DIF_APPENDONLY| \ 191 GFS2_DIF_NOATIME| \ 192 GFS2_DIF_SYNC| \ 193 GFS2_DIF_SYSTEM| \ 194 GFS2_DIF_INHERIT_JDATA) 195 196 /** 197 * gfs2_set_flags - set flags on an inode 198 * @inode: The inode 199 * @flags: The flags to set 200 * @mask: Indicates which flags are valid 201 * 202 */ 203 static int do_gfs2_set_flags(struct file *filp, u32 reqflags, u32 mask) 204 { 205 struct inode *inode = filp->f_path.dentry->d_inode; 206 struct gfs2_inode *ip = GFS2_I(inode); 207 struct gfs2_sbd *sdp = GFS2_SB(inode); 208 struct buffer_head *bh; 209 struct gfs2_holder gh; 210 int error; 211 u32 new_flags, flags; 212 213 error = mnt_want_write(filp->f_path.mnt); 214 if (error) 215 return error; 216 217 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh); 218 if (error) 219 goto out_drop_write; 220 221 error = -EACCES; 222 if (!is_owner_or_cap(inode)) 223 goto out; 224 225 error = 0; 226 flags = ip->i_diskflags; 227 new_flags = (flags & ~mask) | (reqflags & mask); 228 if ((new_flags ^ flags) == 0) 229 goto out; 230 231 error = -EINVAL; 232 if ((new_flags ^ flags) & ~GFS2_FLAGS_USER_SET) 233 goto out; 234 235 error = -EPERM; 236 if (IS_IMMUTABLE(inode) && (new_flags & GFS2_DIF_IMMUTABLE)) 237 goto out; 238 if (IS_APPEND(inode) && (new_flags & GFS2_DIF_APPENDONLY)) 239 goto out; 240 if (((new_flags ^ flags) & GFS2_DIF_IMMUTABLE) && 241 !capable(CAP_LINUX_IMMUTABLE)) 242 goto out; 243 if (!IS_IMMUTABLE(inode)) { 244 error = gfs2_permission(inode, MAY_WRITE); 245 if (error) 246 goto out; 247 } 248 if ((flags ^ new_flags) & GFS2_DIF_JDATA) { 249 if (flags & GFS2_DIF_JDATA) 250 gfs2_log_flush(sdp, ip->i_gl); 251 error = filemap_fdatawrite(inode->i_mapping); 252 if (error) 253 goto out; 254 error = filemap_fdatawait(inode->i_mapping); 255 if (error) 256 goto out; 257 } 258 error = gfs2_trans_begin(sdp, RES_DINODE, 0); 259 if (error) 260 goto out; 261 error = gfs2_meta_inode_buffer(ip, &bh); 262 if (error) 263 goto out_trans_end; 264 gfs2_trans_add_bh(ip->i_gl, bh, 1); 265 ip->i_diskflags = new_flags; 266 gfs2_dinode_out(ip, bh->b_data); 267 brelse(bh); 268 gfs2_set_inode_flags(inode); 269 gfs2_set_aops(inode); 270 out_trans_end: 271 gfs2_trans_end(sdp); 272 out: 273 gfs2_glock_dq_uninit(&gh); 274 out_drop_write: 275 mnt_drop_write(filp->f_path.mnt); 276 return error; 277 } 278 279 static int gfs2_set_flags(struct file *filp, u32 __user *ptr) 280 { 281 struct inode *inode = filp->f_path.dentry->d_inode; 282 u32 fsflags, gfsflags; 283 284 if (get_user(fsflags, ptr)) 285 return -EFAULT; 286 287 gfsflags = fsflags_cvt(fsflags_to_gfs2, fsflags); 288 if (!S_ISDIR(inode->i_mode)) { 289 if (gfsflags & GFS2_DIF_INHERIT_JDATA) 290 gfsflags ^= (GFS2_DIF_JDATA | GFS2_DIF_INHERIT_JDATA); 291 return do_gfs2_set_flags(filp, gfsflags, ~0); 292 } 293 return do_gfs2_set_flags(filp, gfsflags, ~GFS2_DIF_JDATA); 294 } 295 296 static long gfs2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) 297 { 298 switch(cmd) { 299 case FS_IOC_GETFLAGS: 300 return gfs2_get_flags(filp, (u32 __user *)arg); 301 case FS_IOC_SETFLAGS: 302 return gfs2_set_flags(filp, (u32 __user *)arg); 303 } 304 return -ENOTTY; 305 } 306 307 /** 308 * gfs2_allocate_page_backing - Use bmap to allocate blocks 309 * @page: The (locked) page to allocate backing for 310 * 311 * We try to allocate all the blocks required for the page in 312 * one go. This might fail for various reasons, so we keep 313 * trying until all the blocks to back this page are allocated. 314 * If some of the blocks are already allocated, thats ok too. 315 */ 316 317 static int gfs2_allocate_page_backing(struct page *page) 318 { 319 struct inode *inode = page->mapping->host; 320 struct buffer_head bh; 321 unsigned long size = PAGE_CACHE_SIZE; 322 u64 lblock = page->index << (PAGE_CACHE_SHIFT - inode->i_blkbits); 323 324 do { 325 bh.b_state = 0; 326 bh.b_size = size; 327 gfs2_block_map(inode, lblock, &bh, 1); 328 if (!buffer_mapped(&bh)) 329 return -EIO; 330 size -= bh.b_size; 331 lblock += (bh.b_size >> inode->i_blkbits); 332 } while(size > 0); 333 return 0; 334 } 335 336 /** 337 * gfs2_page_mkwrite - Make a shared, mmap()ed, page writable 338 * @vma: The virtual memory area 339 * @page: The page which is about to become writable 340 * 341 * When the page becomes writable, we need to ensure that we have 342 * blocks allocated on disk to back that page. 343 */ 344 345 static int gfs2_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf) 346 { 347 struct page *page = vmf->page; 348 struct inode *inode = vma->vm_file->f_path.dentry->d_inode; 349 struct gfs2_inode *ip = GFS2_I(inode); 350 struct gfs2_sbd *sdp = GFS2_SB(inode); 351 unsigned long last_index; 352 u64 pos = page->index << PAGE_CACHE_SHIFT; 353 unsigned int data_blocks, ind_blocks, rblocks; 354 struct gfs2_holder gh; 355 struct gfs2_alloc *al; 356 int ret; 357 358 gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh); 359 ret = gfs2_glock_nq(&gh); 360 if (ret) 361 goto out; 362 363 set_bit(GLF_DIRTY, &ip->i_gl->gl_flags); 364 set_bit(GIF_SW_PAGED, &ip->i_flags); 365 366 if (!gfs2_write_alloc_required(ip, pos, PAGE_CACHE_SIZE)) 367 goto out_unlock; 368 ret = -ENOMEM; 369 al = gfs2_alloc_get(ip); 370 if (al == NULL) 371 goto out_unlock; 372 373 ret = gfs2_quota_lock_check(ip); 374 if (ret) 375 goto out_alloc_put; 376 gfs2_write_calc_reserv(ip, PAGE_CACHE_SIZE, &data_blocks, &ind_blocks); 377 al->al_requested = data_blocks + ind_blocks; 378 ret = gfs2_inplace_reserve(ip); 379 if (ret) 380 goto out_quota_unlock; 381 382 rblocks = RES_DINODE + ind_blocks; 383 if (gfs2_is_jdata(ip)) 384 rblocks += data_blocks ? data_blocks : 1; 385 if (ind_blocks || data_blocks) { 386 rblocks += RES_STATFS + RES_QUOTA; 387 rblocks += gfs2_rg_blocks(al); 388 } 389 ret = gfs2_trans_begin(sdp, rblocks, 0); 390 if (ret) 391 goto out_trans_fail; 392 393 lock_page(page); 394 ret = -EINVAL; 395 last_index = ip->i_inode.i_size >> PAGE_CACHE_SHIFT; 396 if (page->index > last_index) 397 goto out_unlock_page; 398 ret = 0; 399 if (!PageUptodate(page) || page->mapping != ip->i_inode.i_mapping) 400 goto out_unlock_page; 401 if (gfs2_is_stuffed(ip)) { 402 ret = gfs2_unstuff_dinode(ip, page); 403 if (ret) 404 goto out_unlock_page; 405 } 406 ret = gfs2_allocate_page_backing(page); 407 408 out_unlock_page: 409 unlock_page(page); 410 gfs2_trans_end(sdp); 411 out_trans_fail: 412 gfs2_inplace_release(ip); 413 out_quota_unlock: 414 gfs2_quota_unlock(ip); 415 out_alloc_put: 416 gfs2_alloc_put(ip); 417 out_unlock: 418 gfs2_glock_dq(&gh); 419 out: 420 gfs2_holder_uninit(&gh); 421 if (ret == -ENOMEM) 422 ret = VM_FAULT_OOM; 423 else if (ret) 424 ret = VM_FAULT_SIGBUS; 425 return ret; 426 } 427 428 static const struct vm_operations_struct gfs2_vm_ops = { 429 .fault = filemap_fault, 430 .page_mkwrite = gfs2_page_mkwrite, 431 }; 432 433 /** 434 * gfs2_mmap - 435 * @file: The file to map 436 * @vma: The VMA which described the mapping 437 * 438 * There is no need to get a lock here unless we should be updating 439 * atime. We ignore any locking errors since the only consequence is 440 * a missed atime update (which will just be deferred until later). 441 * 442 * Returns: 0 443 */ 444 445 static int gfs2_mmap(struct file *file, struct vm_area_struct *vma) 446 { 447 struct gfs2_inode *ip = GFS2_I(file->f_mapping->host); 448 449 if (!(file->f_flags & O_NOATIME)) { 450 struct gfs2_holder i_gh; 451 int error; 452 453 gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh); 454 error = gfs2_glock_nq(&i_gh); 455 file_accessed(file); 456 if (error == 0) 457 gfs2_glock_dq_uninit(&i_gh); 458 } 459 vma->vm_ops = &gfs2_vm_ops; 460 vma->vm_flags |= VM_CAN_NONLINEAR; 461 462 return 0; 463 } 464 465 /** 466 * gfs2_open - open a file 467 * @inode: the inode to open 468 * @file: the struct file for this opening 469 * 470 * Returns: errno 471 */ 472 473 static int gfs2_open(struct inode *inode, struct file *file) 474 { 475 struct gfs2_inode *ip = GFS2_I(inode); 476 struct gfs2_holder i_gh; 477 struct gfs2_file *fp; 478 int error; 479 480 fp = kzalloc(sizeof(struct gfs2_file), GFP_KERNEL); 481 if (!fp) 482 return -ENOMEM; 483 484 mutex_init(&fp->f_fl_mutex); 485 486 gfs2_assert_warn(GFS2_SB(inode), !file->private_data); 487 file->private_data = fp; 488 489 if (S_ISREG(ip->i_inode.i_mode)) { 490 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, 491 &i_gh); 492 if (error) 493 goto fail; 494 495 if (!(file->f_flags & O_LARGEFILE) && 496 i_size_read(inode) > MAX_NON_LFS) { 497 error = -EOVERFLOW; 498 goto fail_gunlock; 499 } 500 501 gfs2_glock_dq_uninit(&i_gh); 502 } 503 504 return 0; 505 506 fail_gunlock: 507 gfs2_glock_dq_uninit(&i_gh); 508 fail: 509 file->private_data = NULL; 510 kfree(fp); 511 return error; 512 } 513 514 /** 515 * gfs2_close - called to close a struct file 516 * @inode: the inode the struct file belongs to 517 * @file: the struct file being closed 518 * 519 * Returns: errno 520 */ 521 522 static int gfs2_close(struct inode *inode, struct file *file) 523 { 524 struct gfs2_sbd *sdp = inode->i_sb->s_fs_info; 525 struct gfs2_file *fp; 526 527 fp = file->private_data; 528 file->private_data = NULL; 529 530 if (gfs2_assert_warn(sdp, fp)) 531 return -EIO; 532 533 kfree(fp); 534 535 return 0; 536 } 537 538 /** 539 * gfs2_fsync - sync the dirty data for a file (across the cluster) 540 * @file: the file that points to the dentry (we ignore this) 541 * @dentry: the dentry that points to the inode to sync 542 * 543 * The VFS will flush "normal" data for us. We only need to worry 544 * about metadata here. For journaled data, we just do a log flush 545 * as we can't avoid it. Otherwise we can just bale out if datasync 546 * is set. For stuffed inodes we must flush the log in order to 547 * ensure that all data is on disk. 548 * 549 * The call to write_inode_now() is there to write back metadata and 550 * the inode itself. It does also try and write the data, but thats 551 * (hopefully) a no-op due to the VFS having already called filemap_fdatawrite() 552 * for us. 553 * 554 * Returns: errno 555 */ 556 557 static int gfs2_fsync(struct file *file, int datasync) 558 { 559 struct inode *inode = file->f_mapping->host; 560 int sync_state = inode->i_state & (I_DIRTY_SYNC|I_DIRTY_DATASYNC); 561 int ret = 0; 562 563 if (gfs2_is_jdata(GFS2_I(inode))) { 564 gfs2_log_flush(GFS2_SB(inode), GFS2_I(inode)->i_gl); 565 return 0; 566 } 567 568 if (sync_state != 0) { 569 if (!datasync) 570 ret = write_inode_now(inode, 0); 571 572 if (gfs2_is_stuffed(GFS2_I(inode))) 573 gfs2_log_flush(GFS2_SB(inode), GFS2_I(inode)->i_gl); 574 } 575 576 return ret; 577 } 578 579 /** 580 * gfs2_file_aio_write - Perform a write to a file 581 * @iocb: The io context 582 * @iov: The data to write 583 * @nr_segs: Number of @iov segments 584 * @pos: The file position 585 * 586 * We have to do a lock/unlock here to refresh the inode size for 587 * O_APPEND writes, otherwise we can land up writing at the wrong 588 * offset. There is still a race, but provided the app is using its 589 * own file locking, this will make O_APPEND work as expected. 590 * 591 */ 592 593 static ssize_t gfs2_file_aio_write(struct kiocb *iocb, const struct iovec *iov, 594 unsigned long nr_segs, loff_t pos) 595 { 596 struct file *file = iocb->ki_filp; 597 598 if (file->f_flags & O_APPEND) { 599 struct dentry *dentry = file->f_dentry; 600 struct gfs2_inode *ip = GFS2_I(dentry->d_inode); 601 struct gfs2_holder gh; 602 int ret; 603 604 ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &gh); 605 if (ret) 606 return ret; 607 gfs2_glock_dq_uninit(&gh); 608 } 609 610 return generic_file_aio_write(iocb, iov, nr_segs, pos); 611 } 612 613 #ifdef CONFIG_GFS2_FS_LOCKING_DLM 614 615 /** 616 * gfs2_setlease - acquire/release a file lease 617 * @file: the file pointer 618 * @arg: lease type 619 * @fl: file lock 620 * 621 * We don't currently have a way to enforce a lease across the whole 622 * cluster; until we do, disable leases (by just returning -EINVAL), 623 * unless the administrator has requested purely local locking. 624 * 625 * Locking: called under lock_flocks 626 * 627 * Returns: errno 628 */ 629 630 static int gfs2_setlease(struct file *file, long arg, struct file_lock **fl) 631 { 632 return -EINVAL; 633 } 634 635 /** 636 * gfs2_lock - acquire/release a posix lock on a file 637 * @file: the file pointer 638 * @cmd: either modify or retrieve lock state, possibly wait 639 * @fl: type and range of lock 640 * 641 * Returns: errno 642 */ 643 644 static int gfs2_lock(struct file *file, int cmd, struct file_lock *fl) 645 { 646 struct gfs2_inode *ip = GFS2_I(file->f_mapping->host); 647 struct gfs2_sbd *sdp = GFS2_SB(file->f_mapping->host); 648 struct lm_lockstruct *ls = &sdp->sd_lockstruct; 649 650 if (!(fl->fl_flags & FL_POSIX)) 651 return -ENOLCK; 652 if (__mandatory_lock(&ip->i_inode) && fl->fl_type != F_UNLCK) 653 return -ENOLCK; 654 655 if (cmd == F_CANCELLK) { 656 /* Hack: */ 657 cmd = F_SETLK; 658 fl->fl_type = F_UNLCK; 659 } 660 if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags))) 661 return -EIO; 662 if (IS_GETLK(cmd)) 663 return dlm_posix_get(ls->ls_dlm, ip->i_no_addr, file, fl); 664 else if (fl->fl_type == F_UNLCK) 665 return dlm_posix_unlock(ls->ls_dlm, ip->i_no_addr, file, fl); 666 else 667 return dlm_posix_lock(ls->ls_dlm, ip->i_no_addr, file, cmd, fl); 668 } 669 670 static int do_flock(struct file *file, int cmd, struct file_lock *fl) 671 { 672 struct gfs2_file *fp = file->private_data; 673 struct gfs2_holder *fl_gh = &fp->f_fl_gh; 674 struct gfs2_inode *ip = GFS2_I(file->f_path.dentry->d_inode); 675 struct gfs2_glock *gl; 676 unsigned int state; 677 int flags; 678 int error = 0; 679 680 state = (fl->fl_type == F_WRLCK) ? LM_ST_EXCLUSIVE : LM_ST_SHARED; 681 flags = (IS_SETLKW(cmd) ? 0 : LM_FLAG_TRY) | GL_EXACT | GL_NOCACHE; 682 683 mutex_lock(&fp->f_fl_mutex); 684 685 gl = fl_gh->gh_gl; 686 if (gl) { 687 if (fl_gh->gh_state == state) 688 goto out; 689 flock_lock_file_wait(file, 690 &(struct file_lock){.fl_type = F_UNLCK}); 691 gfs2_glock_dq_wait(fl_gh); 692 gfs2_holder_reinit(state, flags, fl_gh); 693 } else { 694 error = gfs2_glock_get(GFS2_SB(&ip->i_inode), ip->i_no_addr, 695 &gfs2_flock_glops, CREATE, &gl); 696 if (error) 697 goto out; 698 gfs2_holder_init(gl, state, flags, fl_gh); 699 gfs2_glock_put(gl); 700 } 701 error = gfs2_glock_nq(fl_gh); 702 if (error) { 703 gfs2_holder_uninit(fl_gh); 704 if (error == GLR_TRYFAILED) 705 error = -EAGAIN; 706 } else { 707 error = flock_lock_file_wait(file, fl); 708 gfs2_assert_warn(GFS2_SB(&ip->i_inode), !error); 709 } 710 711 out: 712 mutex_unlock(&fp->f_fl_mutex); 713 return error; 714 } 715 716 static void do_unflock(struct file *file, struct file_lock *fl) 717 { 718 struct gfs2_file *fp = file->private_data; 719 struct gfs2_holder *fl_gh = &fp->f_fl_gh; 720 721 mutex_lock(&fp->f_fl_mutex); 722 flock_lock_file_wait(file, fl); 723 if (fl_gh->gh_gl) 724 gfs2_glock_dq_uninit(fl_gh); 725 mutex_unlock(&fp->f_fl_mutex); 726 } 727 728 /** 729 * gfs2_flock - acquire/release a flock lock on a file 730 * @file: the file pointer 731 * @cmd: either modify or retrieve lock state, possibly wait 732 * @fl: type and range of lock 733 * 734 * Returns: errno 735 */ 736 737 static int gfs2_flock(struct file *file, int cmd, struct file_lock *fl) 738 { 739 if (!(fl->fl_flags & FL_FLOCK)) 740 return -ENOLCK; 741 if (fl->fl_type & LOCK_MAND) 742 return -EOPNOTSUPP; 743 744 if (fl->fl_type == F_UNLCK) { 745 do_unflock(file, fl); 746 return 0; 747 } else { 748 return do_flock(file, cmd, fl); 749 } 750 } 751 752 const struct file_operations gfs2_file_fops = { 753 .llseek = gfs2_llseek, 754 .read = do_sync_read, 755 .aio_read = generic_file_aio_read, 756 .write = do_sync_write, 757 .aio_write = gfs2_file_aio_write, 758 .unlocked_ioctl = gfs2_ioctl, 759 .mmap = gfs2_mmap, 760 .open = gfs2_open, 761 .release = gfs2_close, 762 .fsync = gfs2_fsync, 763 .lock = gfs2_lock, 764 .flock = gfs2_flock, 765 .splice_read = generic_file_splice_read, 766 .splice_write = generic_file_splice_write, 767 .setlease = gfs2_setlease, 768 }; 769 770 const struct file_operations gfs2_dir_fops = { 771 .readdir = gfs2_readdir, 772 .unlocked_ioctl = gfs2_ioctl, 773 .open = gfs2_open, 774 .release = gfs2_close, 775 .fsync = gfs2_fsync, 776 .lock = gfs2_lock, 777 .flock = gfs2_flock, 778 .llseek = default_llseek, 779 }; 780 781 #endif /* CONFIG_GFS2_FS_LOCKING_DLM */ 782 783 const struct file_operations gfs2_file_fops_nolock = { 784 .llseek = gfs2_llseek, 785 .read = do_sync_read, 786 .aio_read = generic_file_aio_read, 787 .write = do_sync_write, 788 .aio_write = gfs2_file_aio_write, 789 .unlocked_ioctl = gfs2_ioctl, 790 .mmap = gfs2_mmap, 791 .open = gfs2_open, 792 .release = gfs2_close, 793 .fsync = gfs2_fsync, 794 .splice_read = generic_file_splice_read, 795 .splice_write = generic_file_splice_write, 796 .setlease = generic_setlease, 797 }; 798 799 const struct file_operations gfs2_dir_fops_nolock = { 800 .readdir = gfs2_readdir, 801 .unlocked_ioctl = gfs2_ioctl, 802 .open = gfs2_open, 803 .release = gfs2_close, 804 .fsync = gfs2_fsync, 805 .llseek = default_llseek, 806 }; 807 808