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 ret = gfs2_trans_begin(sdp, rblocks, 0); 388 if (ret) 389 goto out_trans_fail; 390 391 lock_page(page); 392 ret = -EINVAL; 393 last_index = ip->i_inode.i_size >> PAGE_CACHE_SHIFT; 394 if (page->index > last_index) 395 goto out_unlock_page; 396 ret = 0; 397 if (!PageUptodate(page) || page->mapping != ip->i_inode.i_mapping) 398 goto out_unlock_page; 399 if (gfs2_is_stuffed(ip)) { 400 ret = gfs2_unstuff_dinode(ip, page); 401 if (ret) 402 goto out_unlock_page; 403 } 404 ret = gfs2_allocate_page_backing(page); 405 406 out_unlock_page: 407 unlock_page(page); 408 gfs2_trans_end(sdp); 409 out_trans_fail: 410 gfs2_inplace_release(ip); 411 out_quota_unlock: 412 gfs2_quota_unlock(ip); 413 out_alloc_put: 414 gfs2_alloc_put(ip); 415 out_unlock: 416 gfs2_glock_dq(&gh); 417 out: 418 gfs2_holder_uninit(&gh); 419 if (ret == -ENOMEM) 420 ret = VM_FAULT_OOM; 421 else if (ret) 422 ret = VM_FAULT_SIGBUS; 423 return ret; 424 } 425 426 static const struct vm_operations_struct gfs2_vm_ops = { 427 .fault = filemap_fault, 428 .page_mkwrite = gfs2_page_mkwrite, 429 }; 430 431 /** 432 * gfs2_mmap - 433 * @file: The file to map 434 * @vma: The VMA which described the mapping 435 * 436 * There is no need to get a lock here unless we should be updating 437 * atime. We ignore any locking errors since the only consequence is 438 * a missed atime update (which will just be deferred until later). 439 * 440 * Returns: 0 441 */ 442 443 static int gfs2_mmap(struct file *file, struct vm_area_struct *vma) 444 { 445 struct gfs2_inode *ip = GFS2_I(file->f_mapping->host); 446 447 if (!(file->f_flags & O_NOATIME)) { 448 struct gfs2_holder i_gh; 449 int error; 450 451 gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh); 452 error = gfs2_glock_nq(&i_gh); 453 file_accessed(file); 454 if (error == 0) 455 gfs2_glock_dq_uninit(&i_gh); 456 } 457 vma->vm_ops = &gfs2_vm_ops; 458 vma->vm_flags |= VM_CAN_NONLINEAR; 459 460 return 0; 461 } 462 463 /** 464 * gfs2_open - open a file 465 * @inode: the inode to open 466 * @file: the struct file for this opening 467 * 468 * Returns: errno 469 */ 470 471 static int gfs2_open(struct inode *inode, struct file *file) 472 { 473 struct gfs2_inode *ip = GFS2_I(inode); 474 struct gfs2_holder i_gh; 475 struct gfs2_file *fp; 476 int error; 477 478 fp = kzalloc(sizeof(struct gfs2_file), GFP_KERNEL); 479 if (!fp) 480 return -ENOMEM; 481 482 mutex_init(&fp->f_fl_mutex); 483 484 gfs2_assert_warn(GFS2_SB(inode), !file->private_data); 485 file->private_data = fp; 486 487 if (S_ISREG(ip->i_inode.i_mode)) { 488 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, 489 &i_gh); 490 if (error) 491 goto fail; 492 493 if (!(file->f_flags & O_LARGEFILE) && 494 ip->i_disksize > MAX_NON_LFS) { 495 error = -EOVERFLOW; 496 goto fail_gunlock; 497 } 498 499 gfs2_glock_dq_uninit(&i_gh); 500 } 501 502 return 0; 503 504 fail_gunlock: 505 gfs2_glock_dq_uninit(&i_gh); 506 fail: 507 file->private_data = NULL; 508 kfree(fp); 509 return error; 510 } 511 512 /** 513 * gfs2_close - called to close a struct file 514 * @inode: the inode the struct file belongs to 515 * @file: the struct file being closed 516 * 517 * Returns: errno 518 */ 519 520 static int gfs2_close(struct inode *inode, struct file *file) 521 { 522 struct gfs2_sbd *sdp = inode->i_sb->s_fs_info; 523 struct gfs2_file *fp; 524 525 fp = file->private_data; 526 file->private_data = NULL; 527 528 if (gfs2_assert_warn(sdp, fp)) 529 return -EIO; 530 531 kfree(fp); 532 533 return 0; 534 } 535 536 /** 537 * gfs2_fsync - sync the dirty data for a file (across the cluster) 538 * @file: the file that points to the dentry (we ignore this) 539 * @dentry: the dentry that points to the inode to sync 540 * 541 * The VFS will flush "normal" data for us. We only need to worry 542 * about metadata here. For journaled data, we just do a log flush 543 * as we can't avoid it. Otherwise we can just bale out if datasync 544 * is set. For stuffed inodes we must flush the log in order to 545 * ensure that all data is on disk. 546 * 547 * The call to write_inode_now() is there to write back metadata and 548 * the inode itself. It does also try and write the data, but thats 549 * (hopefully) a no-op due to the VFS having already called filemap_fdatawrite() 550 * for us. 551 * 552 * Returns: errno 553 */ 554 555 static int gfs2_fsync(struct file *file, int datasync) 556 { 557 struct inode *inode = file->f_mapping->host; 558 int sync_state = inode->i_state & (I_DIRTY_SYNC|I_DIRTY_DATASYNC); 559 int ret = 0; 560 561 if (gfs2_is_jdata(GFS2_I(inode))) { 562 gfs2_log_flush(GFS2_SB(inode), GFS2_I(inode)->i_gl); 563 return 0; 564 } 565 566 if (sync_state != 0) { 567 if (!datasync) 568 ret = write_inode_now(inode, 0); 569 570 if (gfs2_is_stuffed(GFS2_I(inode))) 571 gfs2_log_flush(GFS2_SB(inode), GFS2_I(inode)->i_gl); 572 } 573 574 return ret; 575 } 576 577 /** 578 * gfs2_file_aio_write - Perform a write to a file 579 * @iocb: The io context 580 * @iov: The data to write 581 * @nr_segs: Number of @iov segments 582 * @pos: The file position 583 * 584 * We have to do a lock/unlock here to refresh the inode size for 585 * O_APPEND writes, otherwise we can land up writing at the wrong 586 * offset. There is still a race, but provided the app is using its 587 * own file locking, this will make O_APPEND work as expected. 588 * 589 */ 590 591 static ssize_t gfs2_file_aio_write(struct kiocb *iocb, const struct iovec *iov, 592 unsigned long nr_segs, loff_t pos) 593 { 594 struct file *file = iocb->ki_filp; 595 596 if (file->f_flags & O_APPEND) { 597 struct dentry *dentry = file->f_dentry; 598 struct gfs2_inode *ip = GFS2_I(dentry->d_inode); 599 struct gfs2_holder gh; 600 int ret; 601 602 ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &gh); 603 if (ret) 604 return ret; 605 gfs2_glock_dq_uninit(&gh); 606 } 607 608 return generic_file_aio_write(iocb, iov, nr_segs, pos); 609 } 610 611 #ifdef CONFIG_GFS2_FS_LOCKING_DLM 612 613 /** 614 * gfs2_setlease - acquire/release a file lease 615 * @file: the file pointer 616 * @arg: lease type 617 * @fl: file lock 618 * 619 * We don't currently have a way to enforce a lease across the whole 620 * cluster; until we do, disable leases (by just returning -EINVAL), 621 * unless the administrator has requested purely local locking. 622 * 623 * Returns: errno 624 */ 625 626 static int gfs2_setlease(struct file *file, long arg, struct file_lock **fl) 627 { 628 return -EINVAL; 629 } 630 631 /** 632 * gfs2_lock - acquire/release a posix lock on a file 633 * @file: the file pointer 634 * @cmd: either modify or retrieve lock state, possibly wait 635 * @fl: type and range of lock 636 * 637 * Returns: errno 638 */ 639 640 static int gfs2_lock(struct file *file, int cmd, struct file_lock *fl) 641 { 642 struct gfs2_inode *ip = GFS2_I(file->f_mapping->host); 643 struct gfs2_sbd *sdp = GFS2_SB(file->f_mapping->host); 644 struct lm_lockstruct *ls = &sdp->sd_lockstruct; 645 646 if (!(fl->fl_flags & FL_POSIX)) 647 return -ENOLCK; 648 if (__mandatory_lock(&ip->i_inode) && fl->fl_type != F_UNLCK) 649 return -ENOLCK; 650 651 if (cmd == F_CANCELLK) { 652 /* Hack: */ 653 cmd = F_SETLK; 654 fl->fl_type = F_UNLCK; 655 } 656 if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags))) 657 return -EIO; 658 if (IS_GETLK(cmd)) 659 return dlm_posix_get(ls->ls_dlm, ip->i_no_addr, file, fl); 660 else if (fl->fl_type == F_UNLCK) 661 return dlm_posix_unlock(ls->ls_dlm, ip->i_no_addr, file, fl); 662 else 663 return dlm_posix_lock(ls->ls_dlm, ip->i_no_addr, file, cmd, fl); 664 } 665 666 static int do_flock(struct file *file, int cmd, struct file_lock *fl) 667 { 668 struct gfs2_file *fp = file->private_data; 669 struct gfs2_holder *fl_gh = &fp->f_fl_gh; 670 struct gfs2_inode *ip = GFS2_I(file->f_path.dentry->d_inode); 671 struct gfs2_glock *gl; 672 unsigned int state; 673 int flags; 674 int error = 0; 675 676 state = (fl->fl_type == F_WRLCK) ? LM_ST_EXCLUSIVE : LM_ST_SHARED; 677 flags = (IS_SETLKW(cmd) ? 0 : LM_FLAG_TRY) | GL_EXACT | GL_NOCACHE; 678 679 mutex_lock(&fp->f_fl_mutex); 680 681 gl = fl_gh->gh_gl; 682 if (gl) { 683 if (fl_gh->gh_state == state) 684 goto out; 685 flock_lock_file_wait(file, 686 &(struct file_lock){.fl_type = F_UNLCK}); 687 gfs2_glock_dq_wait(fl_gh); 688 gfs2_holder_reinit(state, flags, fl_gh); 689 } else { 690 error = gfs2_glock_get(GFS2_SB(&ip->i_inode), ip->i_no_addr, 691 &gfs2_flock_glops, CREATE, &gl); 692 if (error) 693 goto out; 694 gfs2_holder_init(gl, state, flags, fl_gh); 695 gfs2_glock_put(gl); 696 } 697 error = gfs2_glock_nq(fl_gh); 698 if (error) { 699 gfs2_holder_uninit(fl_gh); 700 if (error == GLR_TRYFAILED) 701 error = -EAGAIN; 702 } else { 703 error = flock_lock_file_wait(file, fl); 704 gfs2_assert_warn(GFS2_SB(&ip->i_inode), !error); 705 } 706 707 out: 708 mutex_unlock(&fp->f_fl_mutex); 709 return error; 710 } 711 712 static void do_unflock(struct file *file, struct file_lock *fl) 713 { 714 struct gfs2_file *fp = file->private_data; 715 struct gfs2_holder *fl_gh = &fp->f_fl_gh; 716 717 mutex_lock(&fp->f_fl_mutex); 718 flock_lock_file_wait(file, fl); 719 if (fl_gh->gh_gl) 720 gfs2_glock_dq_uninit(fl_gh); 721 mutex_unlock(&fp->f_fl_mutex); 722 } 723 724 /** 725 * gfs2_flock - acquire/release a flock lock on a file 726 * @file: the file pointer 727 * @cmd: either modify or retrieve lock state, possibly wait 728 * @fl: type and range of lock 729 * 730 * Returns: errno 731 */ 732 733 static int gfs2_flock(struct file *file, int cmd, struct file_lock *fl) 734 { 735 if (!(fl->fl_flags & FL_FLOCK)) 736 return -ENOLCK; 737 if (fl->fl_type & LOCK_MAND) 738 return -EOPNOTSUPP; 739 740 if (fl->fl_type == F_UNLCK) { 741 do_unflock(file, fl); 742 return 0; 743 } else { 744 return do_flock(file, cmd, fl); 745 } 746 } 747 748 const struct file_operations gfs2_file_fops = { 749 .llseek = gfs2_llseek, 750 .read = do_sync_read, 751 .aio_read = generic_file_aio_read, 752 .write = do_sync_write, 753 .aio_write = gfs2_file_aio_write, 754 .unlocked_ioctl = gfs2_ioctl, 755 .mmap = gfs2_mmap, 756 .open = gfs2_open, 757 .release = gfs2_close, 758 .fsync = gfs2_fsync, 759 .lock = gfs2_lock, 760 .flock = gfs2_flock, 761 .splice_read = generic_file_splice_read, 762 .splice_write = generic_file_splice_write, 763 .setlease = gfs2_setlease, 764 }; 765 766 const struct file_operations gfs2_dir_fops = { 767 .readdir = gfs2_readdir, 768 .unlocked_ioctl = gfs2_ioctl, 769 .open = gfs2_open, 770 .release = gfs2_close, 771 .fsync = gfs2_fsync, 772 .lock = gfs2_lock, 773 .flock = gfs2_flock, 774 }; 775 776 #endif /* CONFIG_GFS2_FS_LOCKING_DLM */ 777 778 const struct file_operations gfs2_file_fops_nolock = { 779 .llseek = gfs2_llseek, 780 .read = do_sync_read, 781 .aio_read = generic_file_aio_read, 782 .write = do_sync_write, 783 .aio_write = gfs2_file_aio_write, 784 .unlocked_ioctl = gfs2_ioctl, 785 .mmap = gfs2_mmap, 786 .open = gfs2_open, 787 .release = gfs2_close, 788 .fsync = gfs2_fsync, 789 .splice_read = generic_file_splice_read, 790 .splice_write = generic_file_splice_write, 791 .setlease = generic_setlease, 792 }; 793 794 const struct file_operations gfs2_dir_fops_nolock = { 795 .readdir = gfs2_readdir, 796 .unlocked_ioctl = gfs2_ioctl, 797 .open = gfs2_open, 798 .release = gfs2_close, 799 .fsync = gfs2_fsync, 800 }; 801 802