1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. 4 * Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved. 5 */ 6 7 #include <linux/slab.h> 8 #include <linux/spinlock.h> 9 #include <linux/compat.h> 10 #include <linux/completion.h> 11 #include <linux/buffer_head.h> 12 #include <linux/pagemap.h> 13 #include <linux/uio.h> 14 #include <linux/blkdev.h> 15 #include <linux/mm.h> 16 #include <linux/mount.h> 17 #include <linux/fs.h> 18 #include <linux/filelock.h> 19 #include <linux/gfs2_ondisk.h> 20 #include <linux/falloc.h> 21 #include <linux/swap.h> 22 #include <linux/crc32.h> 23 #include <linux/writeback.h> 24 #include <linux/uaccess.h> 25 #include <linux/dlm.h> 26 #include <linux/dlm_plock.h> 27 #include <linux/delay.h> 28 #include <linux/backing-dev.h> 29 #include <linux/fileattr.h> 30 31 #include "gfs2.h" 32 #include "incore.h" 33 #include "bmap.h" 34 #include "aops.h" 35 #include "dir.h" 36 #include "glock.h" 37 #include "glops.h" 38 #include "inode.h" 39 #include "log.h" 40 #include "meta_io.h" 41 #include "quota.h" 42 #include "rgrp.h" 43 #include "trans.h" 44 #include "util.h" 45 46 /** 47 * gfs2_llseek - seek to a location in a file 48 * @file: the file 49 * @offset: the offset 50 * @whence: Where to seek from (SEEK_SET, SEEK_CUR, or SEEK_END) 51 * 52 * SEEK_END requires the glock for the file because it references the 53 * file's size. 54 * 55 * Returns: The new offset, or errno 56 */ 57 58 static loff_t gfs2_llseek(struct file *file, loff_t offset, int whence) 59 { 60 struct gfs2_inode *ip = GFS2_I(file->f_mapping->host); 61 struct gfs2_holder i_gh; 62 loff_t error; 63 64 switch (whence) { 65 case SEEK_END: 66 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, 67 &i_gh); 68 if (!error) { 69 error = generic_file_llseek(file, offset, whence); 70 gfs2_glock_dq_uninit(&i_gh); 71 } 72 break; 73 74 case SEEK_DATA: 75 error = gfs2_seek_data(file, offset); 76 break; 77 78 case SEEK_HOLE: 79 error = gfs2_seek_hole(file, offset); 80 break; 81 82 case SEEK_CUR: 83 case SEEK_SET: 84 /* 85 * These don't reference inode->i_size and don't depend on the 86 * block mapping, so we don't need the glock. 87 */ 88 error = generic_file_llseek(file, offset, whence); 89 break; 90 default: 91 error = -EINVAL; 92 } 93 94 return error; 95 } 96 97 /** 98 * gfs2_readdir - Iterator for a directory 99 * @file: The directory to read from 100 * @ctx: What to feed directory entries to 101 * 102 * Returns: errno 103 */ 104 105 static int gfs2_readdir(struct file *file, struct dir_context *ctx) 106 { 107 struct inode *dir = file->f_mapping->host; 108 struct gfs2_inode *dip = GFS2_I(dir); 109 struct gfs2_holder d_gh; 110 int error; 111 112 error = gfs2_glock_nq_init(dip->i_gl, LM_ST_SHARED, 0, &d_gh); 113 if (error) 114 return error; 115 116 error = gfs2_dir_read(dir, ctx, &file->f_ra); 117 118 gfs2_glock_dq_uninit(&d_gh); 119 120 return error; 121 } 122 123 /* 124 * struct fsflag_gfs2flag 125 * 126 * The FS_JOURNAL_DATA_FL flag maps to GFS2_DIF_INHERIT_JDATA for directories, 127 * and to GFS2_DIF_JDATA for non-directories. 128 */ 129 static struct { 130 u32 fsflag; 131 u32 gfsflag; 132 } fsflag_gfs2flag[] = { 133 {FS_SYNC_FL, GFS2_DIF_SYNC}, 134 {FS_IMMUTABLE_FL, GFS2_DIF_IMMUTABLE}, 135 {FS_APPEND_FL, GFS2_DIF_APPENDONLY}, 136 {FS_NOATIME_FL, GFS2_DIF_NOATIME}, 137 {FS_INDEX_FL, GFS2_DIF_EXHASH}, 138 {FS_TOPDIR_FL, GFS2_DIF_TOPDIR}, 139 {FS_JOURNAL_DATA_FL, GFS2_DIF_JDATA | GFS2_DIF_INHERIT_JDATA}, 140 }; 141 142 static inline u32 gfs2_gfsflags_to_fsflags(struct inode *inode, u32 gfsflags) 143 { 144 int i; 145 u32 fsflags = 0; 146 147 if (S_ISDIR(inode->i_mode)) 148 gfsflags &= ~GFS2_DIF_JDATA; 149 else 150 gfsflags &= ~GFS2_DIF_INHERIT_JDATA; 151 152 for (i = 0; i < ARRAY_SIZE(fsflag_gfs2flag); i++) 153 if (gfsflags & fsflag_gfs2flag[i].gfsflag) 154 fsflags |= fsflag_gfs2flag[i].fsflag; 155 return fsflags; 156 } 157 158 int gfs2_fileattr_get(struct dentry *dentry, struct fileattr *fa) 159 { 160 struct inode *inode = d_inode(dentry); 161 struct gfs2_inode *ip = GFS2_I(inode); 162 struct gfs2_holder gh; 163 int error; 164 u32 fsflags; 165 166 if (d_is_special(dentry)) 167 return -ENOTTY; 168 169 gfs2_holder_init(ip->i_gl, LM_ST_SHARED, 0, &gh); 170 error = gfs2_glock_nq(&gh); 171 if (error) 172 goto out_uninit; 173 174 fsflags = gfs2_gfsflags_to_fsflags(inode, ip->i_diskflags); 175 176 fileattr_fill_flags(fa, fsflags); 177 178 gfs2_glock_dq(&gh); 179 out_uninit: 180 gfs2_holder_uninit(&gh); 181 return error; 182 } 183 184 void gfs2_set_inode_flags(struct inode *inode) 185 { 186 struct gfs2_inode *ip = GFS2_I(inode); 187 unsigned int flags = inode->i_flags; 188 189 flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC|S_NOSEC); 190 if ((ip->i_eattr == 0) && !is_sxid(inode->i_mode)) 191 flags |= S_NOSEC; 192 if (ip->i_diskflags & GFS2_DIF_IMMUTABLE) 193 flags |= S_IMMUTABLE; 194 if (ip->i_diskflags & GFS2_DIF_APPENDONLY) 195 flags |= S_APPEND; 196 if (ip->i_diskflags & GFS2_DIF_NOATIME) 197 flags |= S_NOATIME; 198 if (ip->i_diskflags & GFS2_DIF_SYNC) 199 flags |= S_SYNC; 200 inode->i_flags = flags; 201 } 202 203 /* Flags that can be set by user space */ 204 #define GFS2_FLAGS_USER_SET (GFS2_DIF_JDATA| \ 205 GFS2_DIF_IMMUTABLE| \ 206 GFS2_DIF_APPENDONLY| \ 207 GFS2_DIF_NOATIME| \ 208 GFS2_DIF_SYNC| \ 209 GFS2_DIF_TOPDIR| \ 210 GFS2_DIF_INHERIT_JDATA) 211 212 /** 213 * do_gfs2_set_flags - set flags on an inode 214 * @inode: The inode 215 * @reqflags: The flags to set 216 * @mask: Indicates which flags are valid 217 * 218 */ 219 static int do_gfs2_set_flags(struct inode *inode, u32 reqflags, u32 mask) 220 { 221 struct gfs2_inode *ip = GFS2_I(inode); 222 struct gfs2_sbd *sdp = GFS2_SB(inode); 223 struct buffer_head *bh; 224 struct gfs2_holder gh; 225 int error; 226 u32 new_flags, flags; 227 228 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh); 229 if (error) 230 return error; 231 232 error = 0; 233 flags = ip->i_diskflags; 234 new_flags = (flags & ~mask) | (reqflags & mask); 235 if ((new_flags ^ flags) == 0) 236 goto out; 237 238 if (!IS_IMMUTABLE(inode)) { 239 error = gfs2_permission(&nop_mnt_idmap, inode, MAY_WRITE); 240 if (error) 241 goto out; 242 } 243 if ((flags ^ new_flags) & GFS2_DIF_JDATA) { 244 if (new_flags & GFS2_DIF_JDATA) 245 gfs2_log_flush(sdp, ip->i_gl, 246 GFS2_LOG_HEAD_FLUSH_NORMAL | 247 GFS2_LFC_SET_FLAGS); 248 error = filemap_fdatawrite(inode->i_mapping); 249 if (error) 250 goto out; 251 error = filemap_fdatawait(inode->i_mapping); 252 if (error) 253 goto out; 254 if (new_flags & GFS2_DIF_JDATA) 255 gfs2_ordered_del_inode(ip); 256 } 257 error = gfs2_trans_begin(sdp, RES_DINODE, 0); 258 if (error) 259 goto out; 260 error = gfs2_meta_inode_buffer(ip, &bh); 261 if (error) 262 goto out_trans_end; 263 inode->i_ctime = current_time(inode); 264 gfs2_trans_add_meta(ip->i_gl, bh); 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 return error; 275 } 276 277 int gfs2_fileattr_set(struct mnt_idmap *idmap, 278 struct dentry *dentry, struct fileattr *fa) 279 { 280 struct inode *inode = d_inode(dentry); 281 u32 fsflags = fa->flags, gfsflags = 0; 282 u32 mask; 283 int i; 284 285 if (d_is_special(dentry)) 286 return -ENOTTY; 287 288 if (fileattr_has_fsx(fa)) 289 return -EOPNOTSUPP; 290 291 for (i = 0; i < ARRAY_SIZE(fsflag_gfs2flag); i++) { 292 if (fsflags & fsflag_gfs2flag[i].fsflag) { 293 fsflags &= ~fsflag_gfs2flag[i].fsflag; 294 gfsflags |= fsflag_gfs2flag[i].gfsflag; 295 } 296 } 297 if (fsflags || gfsflags & ~GFS2_FLAGS_USER_SET) 298 return -EINVAL; 299 300 mask = GFS2_FLAGS_USER_SET; 301 if (S_ISDIR(inode->i_mode)) { 302 mask &= ~GFS2_DIF_JDATA; 303 } else { 304 /* The GFS2_DIF_TOPDIR flag is only valid for directories. */ 305 if (gfsflags & GFS2_DIF_TOPDIR) 306 return -EINVAL; 307 mask &= ~(GFS2_DIF_TOPDIR | GFS2_DIF_INHERIT_JDATA); 308 } 309 310 return do_gfs2_set_flags(inode, gfsflags, mask); 311 } 312 313 static int gfs2_getlabel(struct file *filp, char __user *label) 314 { 315 struct inode *inode = file_inode(filp); 316 struct gfs2_sbd *sdp = GFS2_SB(inode); 317 318 if (copy_to_user(label, sdp->sd_sb.sb_locktable, GFS2_LOCKNAME_LEN)) 319 return -EFAULT; 320 321 return 0; 322 } 323 324 static long gfs2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) 325 { 326 switch(cmd) { 327 case FITRIM: 328 return gfs2_fitrim(filp, (void __user *)arg); 329 case FS_IOC_GETFSLABEL: 330 return gfs2_getlabel(filp, (char __user *)arg); 331 } 332 333 return -ENOTTY; 334 } 335 336 #ifdef CONFIG_COMPAT 337 static long gfs2_compat_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) 338 { 339 switch(cmd) { 340 /* Keep this list in sync with gfs2_ioctl */ 341 case FITRIM: 342 case FS_IOC_GETFSLABEL: 343 break; 344 default: 345 return -ENOIOCTLCMD; 346 } 347 348 return gfs2_ioctl(filp, cmd, (unsigned long)compat_ptr(arg)); 349 } 350 #else 351 #define gfs2_compat_ioctl NULL 352 #endif 353 354 /** 355 * gfs2_size_hint - Give a hint to the size of a write request 356 * @filep: The struct file 357 * @offset: The file offset of the write 358 * @size: The length of the write 359 * 360 * When we are about to do a write, this function records the total 361 * write size in order to provide a suitable hint to the lower layers 362 * about how many blocks will be required. 363 * 364 */ 365 366 static void gfs2_size_hint(struct file *filep, loff_t offset, size_t size) 367 { 368 struct inode *inode = file_inode(filep); 369 struct gfs2_sbd *sdp = GFS2_SB(inode); 370 struct gfs2_inode *ip = GFS2_I(inode); 371 size_t blks = (size + sdp->sd_sb.sb_bsize - 1) >> sdp->sd_sb.sb_bsize_shift; 372 int hint = min_t(size_t, INT_MAX, blks); 373 374 if (hint > atomic_read(&ip->i_sizehint)) 375 atomic_set(&ip->i_sizehint, hint); 376 } 377 378 /** 379 * gfs2_allocate_page_backing - Allocate blocks for a write fault 380 * @page: The (locked) page to allocate backing for 381 * @length: Size of the allocation 382 * 383 * We try to allocate all the blocks required for the page in one go. This 384 * might fail for various reasons, so we keep trying until all the blocks to 385 * back this page are allocated. If some of the blocks are already allocated, 386 * that is ok too. 387 */ 388 static int gfs2_allocate_page_backing(struct page *page, unsigned int length) 389 { 390 u64 pos = page_offset(page); 391 392 do { 393 struct iomap iomap = { }; 394 395 if (gfs2_iomap_alloc(page->mapping->host, pos, length, &iomap)) 396 return -EIO; 397 398 if (length < iomap.length) 399 iomap.length = length; 400 length -= iomap.length; 401 pos += iomap.length; 402 } while (length > 0); 403 404 return 0; 405 } 406 407 /** 408 * gfs2_page_mkwrite - Make a shared, mmap()ed, page writable 409 * @vmf: The virtual memory fault containing the page to become writable 410 * 411 * When the page becomes writable, we need to ensure that we have 412 * blocks allocated on disk to back that page. 413 */ 414 415 static vm_fault_t gfs2_page_mkwrite(struct vm_fault *vmf) 416 { 417 struct page *page = vmf->page; 418 struct inode *inode = file_inode(vmf->vma->vm_file); 419 struct gfs2_inode *ip = GFS2_I(inode); 420 struct gfs2_sbd *sdp = GFS2_SB(inode); 421 struct gfs2_alloc_parms ap = { .aflags = 0, }; 422 u64 offset = page_offset(page); 423 unsigned int data_blocks, ind_blocks, rblocks; 424 vm_fault_t ret = VM_FAULT_LOCKED; 425 struct gfs2_holder gh; 426 unsigned int length; 427 loff_t size; 428 int err; 429 430 sb_start_pagefault(inode->i_sb); 431 432 gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh); 433 err = gfs2_glock_nq(&gh); 434 if (err) { 435 ret = block_page_mkwrite_return(err); 436 goto out_uninit; 437 } 438 439 /* Check page index against inode size */ 440 size = i_size_read(inode); 441 if (offset >= size) { 442 ret = VM_FAULT_SIGBUS; 443 goto out_unlock; 444 } 445 446 /* Update file times before taking page lock */ 447 file_update_time(vmf->vma->vm_file); 448 449 /* page is wholly or partially inside EOF */ 450 if (size - offset < PAGE_SIZE) 451 length = size - offset; 452 else 453 length = PAGE_SIZE; 454 455 gfs2_size_hint(vmf->vma->vm_file, offset, length); 456 457 set_bit(GLF_DIRTY, &ip->i_gl->gl_flags); 458 set_bit(GIF_SW_PAGED, &ip->i_flags); 459 460 /* 461 * iomap_writepage / iomap_writepages currently don't support inline 462 * files, so always unstuff here. 463 */ 464 465 if (!gfs2_is_stuffed(ip) && 466 !gfs2_write_alloc_required(ip, offset, length)) { 467 lock_page(page); 468 if (!PageUptodate(page) || page->mapping != inode->i_mapping) { 469 ret = VM_FAULT_NOPAGE; 470 unlock_page(page); 471 } 472 goto out_unlock; 473 } 474 475 err = gfs2_rindex_update(sdp); 476 if (err) { 477 ret = block_page_mkwrite_return(err); 478 goto out_unlock; 479 } 480 481 gfs2_write_calc_reserv(ip, length, &data_blocks, &ind_blocks); 482 ap.target = data_blocks + ind_blocks; 483 err = gfs2_quota_lock_check(ip, &ap); 484 if (err) { 485 ret = block_page_mkwrite_return(err); 486 goto out_unlock; 487 } 488 err = gfs2_inplace_reserve(ip, &ap); 489 if (err) { 490 ret = block_page_mkwrite_return(err); 491 goto out_quota_unlock; 492 } 493 494 rblocks = RES_DINODE + ind_blocks; 495 if (gfs2_is_jdata(ip)) 496 rblocks += data_blocks ? data_blocks : 1; 497 if (ind_blocks || data_blocks) { 498 rblocks += RES_STATFS + RES_QUOTA; 499 rblocks += gfs2_rg_blocks(ip, data_blocks + ind_blocks); 500 } 501 err = gfs2_trans_begin(sdp, rblocks, 0); 502 if (err) { 503 ret = block_page_mkwrite_return(err); 504 goto out_trans_fail; 505 } 506 507 /* Unstuff, if required, and allocate backing blocks for page */ 508 if (gfs2_is_stuffed(ip)) { 509 err = gfs2_unstuff_dinode(ip); 510 if (err) { 511 ret = block_page_mkwrite_return(err); 512 goto out_trans_end; 513 } 514 } 515 516 lock_page(page); 517 /* If truncated, we must retry the operation, we may have raced 518 * with the glock demotion code. 519 */ 520 if (!PageUptodate(page) || page->mapping != inode->i_mapping) { 521 ret = VM_FAULT_NOPAGE; 522 goto out_page_locked; 523 } 524 525 err = gfs2_allocate_page_backing(page, length); 526 if (err) 527 ret = block_page_mkwrite_return(err); 528 529 out_page_locked: 530 if (ret != VM_FAULT_LOCKED) 531 unlock_page(page); 532 out_trans_end: 533 gfs2_trans_end(sdp); 534 out_trans_fail: 535 gfs2_inplace_release(ip); 536 out_quota_unlock: 537 gfs2_quota_unlock(ip); 538 out_unlock: 539 gfs2_glock_dq(&gh); 540 out_uninit: 541 gfs2_holder_uninit(&gh); 542 if (ret == VM_FAULT_LOCKED) { 543 set_page_dirty(page); 544 wait_for_stable_page(page); 545 } 546 sb_end_pagefault(inode->i_sb); 547 return ret; 548 } 549 550 static vm_fault_t gfs2_fault(struct vm_fault *vmf) 551 { 552 struct inode *inode = file_inode(vmf->vma->vm_file); 553 struct gfs2_inode *ip = GFS2_I(inode); 554 struct gfs2_holder gh; 555 vm_fault_t ret; 556 int err; 557 558 gfs2_holder_init(ip->i_gl, LM_ST_SHARED, 0, &gh); 559 err = gfs2_glock_nq(&gh); 560 if (err) { 561 ret = block_page_mkwrite_return(err); 562 goto out_uninit; 563 } 564 ret = filemap_fault(vmf); 565 gfs2_glock_dq(&gh); 566 out_uninit: 567 gfs2_holder_uninit(&gh); 568 return ret; 569 } 570 571 static const struct vm_operations_struct gfs2_vm_ops = { 572 .fault = gfs2_fault, 573 .map_pages = filemap_map_pages, 574 .page_mkwrite = gfs2_page_mkwrite, 575 }; 576 577 /** 578 * gfs2_mmap 579 * @file: The file to map 580 * @vma: The VMA which described the mapping 581 * 582 * There is no need to get a lock here unless we should be updating 583 * atime. We ignore any locking errors since the only consequence is 584 * a missed atime update (which will just be deferred until later). 585 * 586 * Returns: 0 587 */ 588 589 static int gfs2_mmap(struct file *file, struct vm_area_struct *vma) 590 { 591 struct gfs2_inode *ip = GFS2_I(file->f_mapping->host); 592 593 if (!(file->f_flags & O_NOATIME) && 594 !IS_NOATIME(&ip->i_inode)) { 595 struct gfs2_holder i_gh; 596 int error; 597 598 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, 599 &i_gh); 600 if (error) 601 return error; 602 /* grab lock to update inode */ 603 gfs2_glock_dq_uninit(&i_gh); 604 file_accessed(file); 605 } 606 vma->vm_ops = &gfs2_vm_ops; 607 608 return 0; 609 } 610 611 /** 612 * gfs2_open_common - This is common to open and atomic_open 613 * @inode: The inode being opened 614 * @file: The file being opened 615 * 616 * This maybe called under a glock or not depending upon how it has 617 * been called. We must always be called under a glock for regular 618 * files, however. For other file types, it does not matter whether 619 * we hold the glock or not. 620 * 621 * Returns: Error code or 0 for success 622 */ 623 624 int gfs2_open_common(struct inode *inode, struct file *file) 625 { 626 struct gfs2_file *fp; 627 int ret; 628 629 if (S_ISREG(inode->i_mode)) { 630 ret = generic_file_open(inode, file); 631 if (ret) 632 return ret; 633 } 634 635 fp = kzalloc(sizeof(struct gfs2_file), GFP_NOFS); 636 if (!fp) 637 return -ENOMEM; 638 639 mutex_init(&fp->f_fl_mutex); 640 641 gfs2_assert_warn(GFS2_SB(inode), !file->private_data); 642 file->private_data = fp; 643 if (file->f_mode & FMODE_WRITE) { 644 ret = gfs2_qa_get(GFS2_I(inode)); 645 if (ret) 646 goto fail; 647 } 648 return 0; 649 650 fail: 651 kfree(file->private_data); 652 file->private_data = NULL; 653 return ret; 654 } 655 656 /** 657 * gfs2_open - open a file 658 * @inode: the inode to open 659 * @file: the struct file for this opening 660 * 661 * After atomic_open, this function is only used for opening files 662 * which are already cached. We must still get the glock for regular 663 * files to ensure that we have the file size uptodate for the large 664 * file check which is in the common code. That is only an issue for 665 * regular files though. 666 * 667 * Returns: errno 668 */ 669 670 static int gfs2_open(struct inode *inode, struct file *file) 671 { 672 struct gfs2_inode *ip = GFS2_I(inode); 673 struct gfs2_holder i_gh; 674 int error; 675 bool need_unlock = false; 676 677 if (S_ISREG(ip->i_inode.i_mode)) { 678 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, 679 &i_gh); 680 if (error) 681 return error; 682 need_unlock = true; 683 } 684 685 error = gfs2_open_common(inode, file); 686 687 if (need_unlock) 688 gfs2_glock_dq_uninit(&i_gh); 689 690 return error; 691 } 692 693 /** 694 * gfs2_release - called to close a struct file 695 * @inode: the inode the struct file belongs to 696 * @file: the struct file being closed 697 * 698 * Returns: errno 699 */ 700 701 static int gfs2_release(struct inode *inode, struct file *file) 702 { 703 struct gfs2_inode *ip = GFS2_I(inode); 704 705 kfree(file->private_data); 706 file->private_data = NULL; 707 708 if (file->f_mode & FMODE_WRITE) { 709 if (gfs2_rs_active(&ip->i_res)) 710 gfs2_rs_delete(ip); 711 gfs2_qa_put(ip); 712 } 713 return 0; 714 } 715 716 /** 717 * gfs2_fsync - sync the dirty data for a file (across the cluster) 718 * @file: the file that points to the dentry 719 * @start: the start position in the file to sync 720 * @end: the end position in the file to sync 721 * @datasync: set if we can ignore timestamp changes 722 * 723 * We split the data flushing here so that we don't wait for the data 724 * until after we've also sent the metadata to disk. Note that for 725 * data=ordered, we will write & wait for the data at the log flush 726 * stage anyway, so this is unlikely to make much of a difference 727 * except in the data=writeback case. 728 * 729 * If the fdatawrite fails due to any reason except -EIO, we will 730 * continue the remainder of the fsync, although we'll still report 731 * the error at the end. This is to match filemap_write_and_wait_range() 732 * behaviour. 733 * 734 * Returns: errno 735 */ 736 737 static int gfs2_fsync(struct file *file, loff_t start, loff_t end, 738 int datasync) 739 { 740 struct address_space *mapping = file->f_mapping; 741 struct inode *inode = mapping->host; 742 int sync_state = inode->i_state & I_DIRTY; 743 struct gfs2_inode *ip = GFS2_I(inode); 744 int ret = 0, ret1 = 0; 745 746 if (mapping->nrpages) { 747 ret1 = filemap_fdatawrite_range(mapping, start, end); 748 if (ret1 == -EIO) 749 return ret1; 750 } 751 752 if (!gfs2_is_jdata(ip)) 753 sync_state &= ~I_DIRTY_PAGES; 754 if (datasync) 755 sync_state &= ~I_DIRTY_SYNC; 756 757 if (sync_state) { 758 ret = sync_inode_metadata(inode, 1); 759 if (ret) 760 return ret; 761 if (gfs2_is_jdata(ip)) 762 ret = file_write_and_wait(file); 763 if (ret) 764 return ret; 765 gfs2_ail_flush(ip->i_gl, 1); 766 } 767 768 if (mapping->nrpages) 769 ret = file_fdatawait_range(file, start, end); 770 771 return ret ? ret : ret1; 772 } 773 774 static inline bool should_fault_in_pages(struct iov_iter *i, 775 struct kiocb *iocb, 776 size_t *prev_count, 777 size_t *window_size) 778 { 779 size_t count = iov_iter_count(i); 780 size_t size, offs; 781 782 if (!count) 783 return false; 784 if (!user_backed_iter(i)) 785 return false; 786 787 size = PAGE_SIZE; 788 offs = offset_in_page(iocb->ki_pos); 789 if (*prev_count != count || !*window_size) { 790 size_t nr_dirtied; 791 792 nr_dirtied = max(current->nr_dirtied_pause - 793 current->nr_dirtied, 8); 794 size = min_t(size_t, SZ_1M, nr_dirtied << PAGE_SHIFT); 795 } 796 797 *prev_count = count; 798 *window_size = size - offs; 799 return true; 800 } 801 802 static ssize_t gfs2_file_direct_read(struct kiocb *iocb, struct iov_iter *to, 803 struct gfs2_holder *gh) 804 { 805 struct file *file = iocb->ki_filp; 806 struct gfs2_inode *ip = GFS2_I(file->f_mapping->host); 807 size_t prev_count = 0, window_size = 0; 808 size_t read = 0; 809 ssize_t ret; 810 811 /* 812 * In this function, we disable page faults when we're holding the 813 * inode glock while doing I/O. If a page fault occurs, we indicate 814 * that the inode glock may be dropped, fault in the pages manually, 815 * and retry. 816 * 817 * Unlike generic_file_read_iter, for reads, iomap_dio_rw can trigger 818 * physical as well as manual page faults, and we need to disable both 819 * kinds. 820 * 821 * For direct I/O, gfs2 takes the inode glock in deferred mode. This 822 * locking mode is compatible with other deferred holders, so multiple 823 * processes and nodes can do direct I/O to a file at the same time. 824 * There's no guarantee that reads or writes will be atomic. Any 825 * coordination among readers and writers needs to happen externally. 826 */ 827 828 if (!iov_iter_count(to)) 829 return 0; /* skip atime */ 830 831 gfs2_holder_init(ip->i_gl, LM_ST_DEFERRED, 0, gh); 832 retry: 833 ret = gfs2_glock_nq(gh); 834 if (ret) 835 goto out_uninit; 836 pagefault_disable(); 837 to->nofault = true; 838 ret = iomap_dio_rw(iocb, to, &gfs2_iomap_ops, NULL, 839 IOMAP_DIO_PARTIAL, NULL, read); 840 to->nofault = false; 841 pagefault_enable(); 842 if (ret <= 0 && ret != -EFAULT) 843 goto out_unlock; 844 /* No increment (+=) because iomap_dio_rw returns a cumulative value. */ 845 if (ret > 0) 846 read = ret; 847 848 if (should_fault_in_pages(to, iocb, &prev_count, &window_size)) { 849 gfs2_glock_dq(gh); 850 window_size -= fault_in_iov_iter_writeable(to, window_size); 851 if (window_size) 852 goto retry; 853 } 854 out_unlock: 855 if (gfs2_holder_queued(gh)) 856 gfs2_glock_dq(gh); 857 out_uninit: 858 gfs2_holder_uninit(gh); 859 /* User space doesn't expect partial success. */ 860 if (ret < 0) 861 return ret; 862 return read; 863 } 864 865 static ssize_t gfs2_file_direct_write(struct kiocb *iocb, struct iov_iter *from, 866 struct gfs2_holder *gh) 867 { 868 struct file *file = iocb->ki_filp; 869 struct inode *inode = file->f_mapping->host; 870 struct gfs2_inode *ip = GFS2_I(inode); 871 size_t prev_count = 0, window_size = 0; 872 size_t written = 0; 873 ssize_t ret; 874 875 /* 876 * In this function, we disable page faults when we're holding the 877 * inode glock while doing I/O. If a page fault occurs, we indicate 878 * that the inode glock may be dropped, fault in the pages manually, 879 * and retry. 880 * 881 * For writes, iomap_dio_rw only triggers manual page faults, so we 882 * don't need to disable physical ones. 883 */ 884 885 /* 886 * Deferred lock, even if its a write, since we do no allocation on 887 * this path. All we need to change is the atime, and this lock mode 888 * ensures that other nodes have flushed their buffered read caches 889 * (i.e. their page cache entries for this inode). We do not, 890 * unfortunately, have the option of only flushing a range like the 891 * VFS does. 892 */ 893 gfs2_holder_init(ip->i_gl, LM_ST_DEFERRED, 0, gh); 894 retry: 895 ret = gfs2_glock_nq(gh); 896 if (ret) 897 goto out_uninit; 898 /* Silently fall back to buffered I/O when writing beyond EOF */ 899 if (iocb->ki_pos + iov_iter_count(from) > i_size_read(&ip->i_inode)) 900 goto out_unlock; 901 902 from->nofault = true; 903 ret = iomap_dio_rw(iocb, from, &gfs2_iomap_ops, NULL, 904 IOMAP_DIO_PARTIAL, NULL, written); 905 from->nofault = false; 906 if (ret <= 0) { 907 if (ret == -ENOTBLK) 908 ret = 0; 909 if (ret != -EFAULT) 910 goto out_unlock; 911 } 912 /* No increment (+=) because iomap_dio_rw returns a cumulative value. */ 913 if (ret > 0) 914 written = ret; 915 916 if (should_fault_in_pages(from, iocb, &prev_count, &window_size)) { 917 gfs2_glock_dq(gh); 918 window_size -= fault_in_iov_iter_readable(from, window_size); 919 if (window_size) 920 goto retry; 921 } 922 out_unlock: 923 if (gfs2_holder_queued(gh)) 924 gfs2_glock_dq(gh); 925 out_uninit: 926 gfs2_holder_uninit(gh); 927 /* User space doesn't expect partial success. */ 928 if (ret < 0) 929 return ret; 930 return written; 931 } 932 933 static ssize_t gfs2_file_read_iter(struct kiocb *iocb, struct iov_iter *to) 934 { 935 struct gfs2_inode *ip; 936 struct gfs2_holder gh; 937 size_t prev_count = 0, window_size = 0; 938 size_t read = 0; 939 ssize_t ret; 940 941 /* 942 * In this function, we disable page faults when we're holding the 943 * inode glock while doing I/O. If a page fault occurs, we indicate 944 * that the inode glock may be dropped, fault in the pages manually, 945 * and retry. 946 */ 947 948 if (iocb->ki_flags & IOCB_DIRECT) 949 return gfs2_file_direct_read(iocb, to, &gh); 950 951 pagefault_disable(); 952 iocb->ki_flags |= IOCB_NOIO; 953 ret = generic_file_read_iter(iocb, to); 954 iocb->ki_flags &= ~IOCB_NOIO; 955 pagefault_enable(); 956 if (ret >= 0) { 957 if (!iov_iter_count(to)) 958 return ret; 959 read = ret; 960 } else if (ret != -EFAULT) { 961 if (ret != -EAGAIN) 962 return ret; 963 if (iocb->ki_flags & IOCB_NOWAIT) 964 return ret; 965 } 966 ip = GFS2_I(iocb->ki_filp->f_mapping->host); 967 gfs2_holder_init(ip->i_gl, LM_ST_SHARED, 0, &gh); 968 retry: 969 ret = gfs2_glock_nq(&gh); 970 if (ret) 971 goto out_uninit; 972 pagefault_disable(); 973 ret = generic_file_read_iter(iocb, to); 974 pagefault_enable(); 975 if (ret <= 0 && ret != -EFAULT) 976 goto out_unlock; 977 if (ret > 0) 978 read += ret; 979 980 if (should_fault_in_pages(to, iocb, &prev_count, &window_size)) { 981 gfs2_glock_dq(&gh); 982 window_size -= fault_in_iov_iter_writeable(to, window_size); 983 if (window_size) 984 goto retry; 985 } 986 out_unlock: 987 if (gfs2_holder_queued(&gh)) 988 gfs2_glock_dq(&gh); 989 out_uninit: 990 gfs2_holder_uninit(&gh); 991 return read ? read : ret; 992 } 993 994 static ssize_t gfs2_file_buffered_write(struct kiocb *iocb, 995 struct iov_iter *from, 996 struct gfs2_holder *gh) 997 { 998 struct file *file = iocb->ki_filp; 999 struct inode *inode = file_inode(file); 1000 struct gfs2_inode *ip = GFS2_I(inode); 1001 struct gfs2_sbd *sdp = GFS2_SB(inode); 1002 struct gfs2_holder *statfs_gh = NULL; 1003 size_t prev_count = 0, window_size = 0; 1004 size_t orig_count = iov_iter_count(from); 1005 size_t written = 0; 1006 ssize_t ret; 1007 1008 /* 1009 * In this function, we disable page faults when we're holding the 1010 * inode glock while doing I/O. If a page fault occurs, we indicate 1011 * that the inode glock may be dropped, fault in the pages manually, 1012 * and retry. 1013 */ 1014 1015 if (inode == sdp->sd_rindex) { 1016 statfs_gh = kmalloc(sizeof(*statfs_gh), GFP_NOFS); 1017 if (!statfs_gh) 1018 return -ENOMEM; 1019 } 1020 1021 gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, gh); 1022 retry: 1023 if (should_fault_in_pages(from, iocb, &prev_count, &window_size)) { 1024 window_size -= fault_in_iov_iter_readable(from, window_size); 1025 if (!window_size) { 1026 ret = -EFAULT; 1027 goto out_uninit; 1028 } 1029 from->count = min(from->count, window_size); 1030 } 1031 ret = gfs2_glock_nq(gh); 1032 if (ret) 1033 goto out_uninit; 1034 1035 if (inode == sdp->sd_rindex) { 1036 struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode); 1037 1038 ret = gfs2_glock_nq_init(m_ip->i_gl, LM_ST_EXCLUSIVE, 1039 GL_NOCACHE, statfs_gh); 1040 if (ret) 1041 goto out_unlock; 1042 } 1043 1044 current->backing_dev_info = inode_to_bdi(inode); 1045 pagefault_disable(); 1046 ret = iomap_file_buffered_write(iocb, from, &gfs2_iomap_ops); 1047 pagefault_enable(); 1048 current->backing_dev_info = NULL; 1049 if (ret > 0) { 1050 iocb->ki_pos += ret; 1051 written += ret; 1052 } 1053 1054 if (inode == sdp->sd_rindex) 1055 gfs2_glock_dq_uninit(statfs_gh); 1056 1057 if (ret <= 0 && ret != -EFAULT) 1058 goto out_unlock; 1059 1060 from->count = orig_count - written; 1061 if (should_fault_in_pages(from, iocb, &prev_count, &window_size)) { 1062 gfs2_glock_dq(gh); 1063 goto retry; 1064 } 1065 out_unlock: 1066 if (gfs2_holder_queued(gh)) 1067 gfs2_glock_dq(gh); 1068 out_uninit: 1069 gfs2_holder_uninit(gh); 1070 kfree(statfs_gh); 1071 from->count = orig_count - written; 1072 return written ? written : ret; 1073 } 1074 1075 /** 1076 * gfs2_file_write_iter - Perform a write to a file 1077 * @iocb: The io context 1078 * @from: The data to write 1079 * 1080 * We have to do a lock/unlock here to refresh the inode size for 1081 * O_APPEND writes, otherwise we can land up writing at the wrong 1082 * offset. There is still a race, but provided the app is using its 1083 * own file locking, this will make O_APPEND work as expected. 1084 * 1085 */ 1086 1087 static ssize_t gfs2_file_write_iter(struct kiocb *iocb, struct iov_iter *from) 1088 { 1089 struct file *file = iocb->ki_filp; 1090 struct inode *inode = file_inode(file); 1091 struct gfs2_inode *ip = GFS2_I(inode); 1092 struct gfs2_holder gh; 1093 ssize_t ret; 1094 1095 gfs2_size_hint(file, iocb->ki_pos, iov_iter_count(from)); 1096 1097 if (iocb->ki_flags & IOCB_APPEND) { 1098 ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &gh); 1099 if (ret) 1100 return ret; 1101 gfs2_glock_dq_uninit(&gh); 1102 } 1103 1104 inode_lock(inode); 1105 ret = generic_write_checks(iocb, from); 1106 if (ret <= 0) 1107 goto out_unlock; 1108 1109 ret = file_remove_privs(file); 1110 if (ret) 1111 goto out_unlock; 1112 1113 ret = file_update_time(file); 1114 if (ret) 1115 goto out_unlock; 1116 1117 if (iocb->ki_flags & IOCB_DIRECT) { 1118 struct address_space *mapping = file->f_mapping; 1119 ssize_t buffered, ret2; 1120 1121 ret = gfs2_file_direct_write(iocb, from, &gh); 1122 if (ret < 0 || !iov_iter_count(from)) 1123 goto out_unlock; 1124 1125 iocb->ki_flags |= IOCB_DSYNC; 1126 buffered = gfs2_file_buffered_write(iocb, from, &gh); 1127 if (unlikely(buffered <= 0)) { 1128 if (!ret) 1129 ret = buffered; 1130 goto out_unlock; 1131 } 1132 1133 /* 1134 * We need to ensure that the page cache pages are written to 1135 * disk and invalidated to preserve the expected O_DIRECT 1136 * semantics. If the writeback or invalidate fails, only report 1137 * the direct I/O range as we don't know if the buffered pages 1138 * made it to disk. 1139 */ 1140 ret2 = generic_write_sync(iocb, buffered); 1141 invalidate_mapping_pages(mapping, 1142 (iocb->ki_pos - buffered) >> PAGE_SHIFT, 1143 (iocb->ki_pos - 1) >> PAGE_SHIFT); 1144 if (!ret || ret2 > 0) 1145 ret += ret2; 1146 } else { 1147 ret = gfs2_file_buffered_write(iocb, from, &gh); 1148 if (likely(ret > 0)) 1149 ret = generic_write_sync(iocb, ret); 1150 } 1151 1152 out_unlock: 1153 inode_unlock(inode); 1154 return ret; 1155 } 1156 1157 static int fallocate_chunk(struct inode *inode, loff_t offset, loff_t len, 1158 int mode) 1159 { 1160 struct super_block *sb = inode->i_sb; 1161 struct gfs2_inode *ip = GFS2_I(inode); 1162 loff_t end = offset + len; 1163 struct buffer_head *dibh; 1164 int error; 1165 1166 error = gfs2_meta_inode_buffer(ip, &dibh); 1167 if (unlikely(error)) 1168 return error; 1169 1170 gfs2_trans_add_meta(ip->i_gl, dibh); 1171 1172 if (gfs2_is_stuffed(ip)) { 1173 error = gfs2_unstuff_dinode(ip); 1174 if (unlikely(error)) 1175 goto out; 1176 } 1177 1178 while (offset < end) { 1179 struct iomap iomap = { }; 1180 1181 error = gfs2_iomap_alloc(inode, offset, end - offset, &iomap); 1182 if (error) 1183 goto out; 1184 offset = iomap.offset + iomap.length; 1185 if (!(iomap.flags & IOMAP_F_NEW)) 1186 continue; 1187 error = sb_issue_zeroout(sb, iomap.addr >> inode->i_blkbits, 1188 iomap.length >> inode->i_blkbits, 1189 GFP_NOFS); 1190 if (error) { 1191 fs_err(GFS2_SB(inode), "Failed to zero data buffers\n"); 1192 goto out; 1193 } 1194 } 1195 out: 1196 brelse(dibh); 1197 return error; 1198 } 1199 1200 /** 1201 * calc_max_reserv() - Reverse of write_calc_reserv. Given a number of 1202 * blocks, determine how many bytes can be written. 1203 * @ip: The inode in question. 1204 * @len: Max cap of bytes. What we return in *len must be <= this. 1205 * @data_blocks: Compute and return the number of data blocks needed 1206 * @ind_blocks: Compute and return the number of indirect blocks needed 1207 * @max_blocks: The total blocks available to work with. 1208 * 1209 * Returns: void, but @len, @data_blocks and @ind_blocks are filled in. 1210 */ 1211 static void calc_max_reserv(struct gfs2_inode *ip, loff_t *len, 1212 unsigned int *data_blocks, unsigned int *ind_blocks, 1213 unsigned int max_blocks) 1214 { 1215 loff_t max = *len; 1216 const struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode); 1217 unsigned int tmp, max_data = max_blocks - 3 * (sdp->sd_max_height - 1); 1218 1219 for (tmp = max_data; tmp > sdp->sd_diptrs;) { 1220 tmp = DIV_ROUND_UP(tmp, sdp->sd_inptrs); 1221 max_data -= tmp; 1222 } 1223 1224 *data_blocks = max_data; 1225 *ind_blocks = max_blocks - max_data; 1226 *len = ((loff_t)max_data - 3) << sdp->sd_sb.sb_bsize_shift; 1227 if (*len > max) { 1228 *len = max; 1229 gfs2_write_calc_reserv(ip, max, data_blocks, ind_blocks); 1230 } 1231 } 1232 1233 static long __gfs2_fallocate(struct file *file, int mode, loff_t offset, loff_t len) 1234 { 1235 struct inode *inode = file_inode(file); 1236 struct gfs2_sbd *sdp = GFS2_SB(inode); 1237 struct gfs2_inode *ip = GFS2_I(inode); 1238 struct gfs2_alloc_parms ap = { .aflags = 0, }; 1239 unsigned int data_blocks = 0, ind_blocks = 0, rblocks; 1240 loff_t bytes, max_bytes, max_blks; 1241 int error; 1242 const loff_t pos = offset; 1243 const loff_t count = len; 1244 loff_t bsize_mask = ~((loff_t)sdp->sd_sb.sb_bsize - 1); 1245 loff_t next = (offset + len - 1) >> sdp->sd_sb.sb_bsize_shift; 1246 loff_t max_chunk_size = UINT_MAX & bsize_mask; 1247 1248 next = (next + 1) << sdp->sd_sb.sb_bsize_shift; 1249 1250 offset &= bsize_mask; 1251 1252 len = next - offset; 1253 bytes = sdp->sd_max_rg_data * sdp->sd_sb.sb_bsize / 2; 1254 if (!bytes) 1255 bytes = UINT_MAX; 1256 bytes &= bsize_mask; 1257 if (bytes == 0) 1258 bytes = sdp->sd_sb.sb_bsize; 1259 1260 gfs2_size_hint(file, offset, len); 1261 1262 gfs2_write_calc_reserv(ip, PAGE_SIZE, &data_blocks, &ind_blocks); 1263 ap.min_target = data_blocks + ind_blocks; 1264 1265 while (len > 0) { 1266 if (len < bytes) 1267 bytes = len; 1268 if (!gfs2_write_alloc_required(ip, offset, bytes)) { 1269 len -= bytes; 1270 offset += bytes; 1271 continue; 1272 } 1273 1274 /* We need to determine how many bytes we can actually 1275 * fallocate without exceeding quota or going over the 1276 * end of the fs. We start off optimistically by assuming 1277 * we can write max_bytes */ 1278 max_bytes = (len > max_chunk_size) ? max_chunk_size : len; 1279 1280 /* Since max_bytes is most likely a theoretical max, we 1281 * calculate a more realistic 'bytes' to serve as a good 1282 * starting point for the number of bytes we may be able 1283 * to write */ 1284 gfs2_write_calc_reserv(ip, bytes, &data_blocks, &ind_blocks); 1285 ap.target = data_blocks + ind_blocks; 1286 1287 error = gfs2_quota_lock_check(ip, &ap); 1288 if (error) 1289 return error; 1290 /* ap.allowed tells us how many blocks quota will allow 1291 * us to write. Check if this reduces max_blks */ 1292 max_blks = UINT_MAX; 1293 if (ap.allowed) 1294 max_blks = ap.allowed; 1295 1296 error = gfs2_inplace_reserve(ip, &ap); 1297 if (error) 1298 goto out_qunlock; 1299 1300 /* check if the selected rgrp limits our max_blks further */ 1301 if (ip->i_res.rs_reserved < max_blks) 1302 max_blks = ip->i_res.rs_reserved; 1303 1304 /* Almost done. Calculate bytes that can be written using 1305 * max_blks. We also recompute max_bytes, data_blocks and 1306 * ind_blocks */ 1307 calc_max_reserv(ip, &max_bytes, &data_blocks, 1308 &ind_blocks, max_blks); 1309 1310 rblocks = RES_DINODE + ind_blocks + RES_STATFS + RES_QUOTA + 1311 RES_RG_HDR + gfs2_rg_blocks(ip, data_blocks + ind_blocks); 1312 if (gfs2_is_jdata(ip)) 1313 rblocks += data_blocks ? data_blocks : 1; 1314 1315 error = gfs2_trans_begin(sdp, rblocks, 1316 PAGE_SIZE >> inode->i_blkbits); 1317 if (error) 1318 goto out_trans_fail; 1319 1320 error = fallocate_chunk(inode, offset, max_bytes, mode); 1321 gfs2_trans_end(sdp); 1322 1323 if (error) 1324 goto out_trans_fail; 1325 1326 len -= max_bytes; 1327 offset += max_bytes; 1328 gfs2_inplace_release(ip); 1329 gfs2_quota_unlock(ip); 1330 } 1331 1332 if (!(mode & FALLOC_FL_KEEP_SIZE) && (pos + count) > inode->i_size) 1333 i_size_write(inode, pos + count); 1334 file_update_time(file); 1335 mark_inode_dirty(inode); 1336 1337 if ((file->f_flags & O_DSYNC) || IS_SYNC(file->f_mapping->host)) 1338 return vfs_fsync_range(file, pos, pos + count - 1, 1339 (file->f_flags & __O_SYNC) ? 0 : 1); 1340 return 0; 1341 1342 out_trans_fail: 1343 gfs2_inplace_release(ip); 1344 out_qunlock: 1345 gfs2_quota_unlock(ip); 1346 return error; 1347 } 1348 1349 static long gfs2_fallocate(struct file *file, int mode, loff_t offset, loff_t len) 1350 { 1351 struct inode *inode = file_inode(file); 1352 struct gfs2_sbd *sdp = GFS2_SB(inode); 1353 struct gfs2_inode *ip = GFS2_I(inode); 1354 struct gfs2_holder gh; 1355 int ret; 1356 1357 if (mode & ~(FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE)) 1358 return -EOPNOTSUPP; 1359 /* fallocate is needed by gfs2_grow to reserve space in the rindex */ 1360 if (gfs2_is_jdata(ip) && inode != sdp->sd_rindex) 1361 return -EOPNOTSUPP; 1362 1363 inode_lock(inode); 1364 1365 gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh); 1366 ret = gfs2_glock_nq(&gh); 1367 if (ret) 1368 goto out_uninit; 1369 1370 if (!(mode & FALLOC_FL_KEEP_SIZE) && 1371 (offset + len) > inode->i_size) { 1372 ret = inode_newsize_ok(inode, offset + len); 1373 if (ret) 1374 goto out_unlock; 1375 } 1376 1377 ret = get_write_access(inode); 1378 if (ret) 1379 goto out_unlock; 1380 1381 if (mode & FALLOC_FL_PUNCH_HOLE) { 1382 ret = __gfs2_punch_hole(file, offset, len); 1383 } else { 1384 ret = __gfs2_fallocate(file, mode, offset, len); 1385 if (ret) 1386 gfs2_rs_deltree(&ip->i_res); 1387 } 1388 1389 put_write_access(inode); 1390 out_unlock: 1391 gfs2_glock_dq(&gh); 1392 out_uninit: 1393 gfs2_holder_uninit(&gh); 1394 inode_unlock(inode); 1395 return ret; 1396 } 1397 1398 static ssize_t gfs2_file_splice_write(struct pipe_inode_info *pipe, 1399 struct file *out, loff_t *ppos, 1400 size_t len, unsigned int flags) 1401 { 1402 ssize_t ret; 1403 1404 gfs2_size_hint(out, *ppos, len); 1405 1406 ret = iter_file_splice_write(pipe, out, ppos, len, flags); 1407 return ret; 1408 } 1409 1410 #ifdef CONFIG_GFS2_FS_LOCKING_DLM 1411 1412 /** 1413 * gfs2_lock - acquire/release a posix lock on a file 1414 * @file: the file pointer 1415 * @cmd: either modify or retrieve lock state, possibly wait 1416 * @fl: type and range of lock 1417 * 1418 * Returns: errno 1419 */ 1420 1421 static int gfs2_lock(struct file *file, int cmd, struct file_lock *fl) 1422 { 1423 struct gfs2_inode *ip = GFS2_I(file->f_mapping->host); 1424 struct gfs2_sbd *sdp = GFS2_SB(file->f_mapping->host); 1425 struct lm_lockstruct *ls = &sdp->sd_lockstruct; 1426 1427 if (!(fl->fl_flags & FL_POSIX)) 1428 return -ENOLCK; 1429 if (cmd == F_CANCELLK) { 1430 /* Hack: */ 1431 cmd = F_SETLK; 1432 fl->fl_type = F_UNLCK; 1433 } 1434 if (unlikely(gfs2_withdrawn(sdp))) { 1435 if (fl->fl_type == F_UNLCK) 1436 locks_lock_file_wait(file, fl); 1437 return -EIO; 1438 } 1439 if (IS_GETLK(cmd)) 1440 return dlm_posix_get(ls->ls_dlm, ip->i_no_addr, file, fl); 1441 else if (fl->fl_type == F_UNLCK) 1442 return dlm_posix_unlock(ls->ls_dlm, ip->i_no_addr, file, fl); 1443 else 1444 return dlm_posix_lock(ls->ls_dlm, ip->i_no_addr, file, cmd, fl); 1445 } 1446 1447 static void __flock_holder_uninit(struct file *file, struct gfs2_holder *fl_gh) 1448 { 1449 struct gfs2_glock *gl = gfs2_glock_hold(fl_gh->gh_gl); 1450 1451 /* 1452 * Make sure gfs2_glock_put() won't sleep under the file->f_lock 1453 * spinlock. 1454 */ 1455 1456 spin_lock(&file->f_lock); 1457 gfs2_holder_uninit(fl_gh); 1458 spin_unlock(&file->f_lock); 1459 gfs2_glock_put(gl); 1460 } 1461 1462 static int do_flock(struct file *file, int cmd, struct file_lock *fl) 1463 { 1464 struct gfs2_file *fp = file->private_data; 1465 struct gfs2_holder *fl_gh = &fp->f_fl_gh; 1466 struct gfs2_inode *ip = GFS2_I(file_inode(file)); 1467 struct gfs2_glock *gl; 1468 unsigned int state; 1469 u16 flags; 1470 int error = 0; 1471 int sleeptime; 1472 1473 state = (fl->fl_type == F_WRLCK) ? LM_ST_EXCLUSIVE : LM_ST_SHARED; 1474 flags = GL_EXACT | GL_NOPID; 1475 if (!IS_SETLKW(cmd)) 1476 flags |= LM_FLAG_TRY_1CB; 1477 1478 mutex_lock(&fp->f_fl_mutex); 1479 1480 if (gfs2_holder_initialized(fl_gh)) { 1481 struct file_lock request; 1482 if (fl_gh->gh_state == state) 1483 goto out; 1484 locks_init_lock(&request); 1485 request.fl_type = F_UNLCK; 1486 request.fl_flags = FL_FLOCK; 1487 locks_lock_file_wait(file, &request); 1488 gfs2_glock_dq(fl_gh); 1489 gfs2_holder_reinit(state, flags, fl_gh); 1490 } else { 1491 error = gfs2_glock_get(GFS2_SB(&ip->i_inode), ip->i_no_addr, 1492 &gfs2_flock_glops, CREATE, &gl); 1493 if (error) 1494 goto out; 1495 spin_lock(&file->f_lock); 1496 gfs2_holder_init(gl, state, flags, fl_gh); 1497 spin_unlock(&file->f_lock); 1498 gfs2_glock_put(gl); 1499 } 1500 for (sleeptime = 1; sleeptime <= 4; sleeptime <<= 1) { 1501 error = gfs2_glock_nq(fl_gh); 1502 if (error != GLR_TRYFAILED) 1503 break; 1504 fl_gh->gh_flags &= ~LM_FLAG_TRY_1CB; 1505 fl_gh->gh_flags |= LM_FLAG_TRY; 1506 msleep(sleeptime); 1507 } 1508 if (error) { 1509 __flock_holder_uninit(file, fl_gh); 1510 if (error == GLR_TRYFAILED) 1511 error = -EAGAIN; 1512 } else { 1513 error = locks_lock_file_wait(file, fl); 1514 gfs2_assert_warn(GFS2_SB(&ip->i_inode), !error); 1515 } 1516 1517 out: 1518 mutex_unlock(&fp->f_fl_mutex); 1519 return error; 1520 } 1521 1522 static void do_unflock(struct file *file, struct file_lock *fl) 1523 { 1524 struct gfs2_file *fp = file->private_data; 1525 struct gfs2_holder *fl_gh = &fp->f_fl_gh; 1526 1527 mutex_lock(&fp->f_fl_mutex); 1528 locks_lock_file_wait(file, fl); 1529 if (gfs2_holder_initialized(fl_gh)) { 1530 gfs2_glock_dq(fl_gh); 1531 __flock_holder_uninit(file, fl_gh); 1532 } 1533 mutex_unlock(&fp->f_fl_mutex); 1534 } 1535 1536 /** 1537 * gfs2_flock - acquire/release a flock lock on a file 1538 * @file: the file pointer 1539 * @cmd: either modify or retrieve lock state, possibly wait 1540 * @fl: type and range of lock 1541 * 1542 * Returns: errno 1543 */ 1544 1545 static int gfs2_flock(struct file *file, int cmd, struct file_lock *fl) 1546 { 1547 if (!(fl->fl_flags & FL_FLOCK)) 1548 return -ENOLCK; 1549 1550 if (fl->fl_type == F_UNLCK) { 1551 do_unflock(file, fl); 1552 return 0; 1553 } else { 1554 return do_flock(file, cmd, fl); 1555 } 1556 } 1557 1558 const struct file_operations gfs2_file_fops = { 1559 .llseek = gfs2_llseek, 1560 .read_iter = gfs2_file_read_iter, 1561 .write_iter = gfs2_file_write_iter, 1562 .iopoll = iocb_bio_iopoll, 1563 .unlocked_ioctl = gfs2_ioctl, 1564 .compat_ioctl = gfs2_compat_ioctl, 1565 .mmap = gfs2_mmap, 1566 .open = gfs2_open, 1567 .release = gfs2_release, 1568 .fsync = gfs2_fsync, 1569 .lock = gfs2_lock, 1570 .flock = gfs2_flock, 1571 .splice_read = generic_file_splice_read, 1572 .splice_write = gfs2_file_splice_write, 1573 .setlease = simple_nosetlease, 1574 .fallocate = gfs2_fallocate, 1575 }; 1576 1577 const struct file_operations gfs2_dir_fops = { 1578 .iterate_shared = gfs2_readdir, 1579 .unlocked_ioctl = gfs2_ioctl, 1580 .compat_ioctl = gfs2_compat_ioctl, 1581 .open = gfs2_open, 1582 .release = gfs2_release, 1583 .fsync = gfs2_fsync, 1584 .lock = gfs2_lock, 1585 .flock = gfs2_flock, 1586 .llseek = default_llseek, 1587 }; 1588 1589 #endif /* CONFIG_GFS2_FS_LOCKING_DLM */ 1590 1591 const struct file_operations gfs2_file_fops_nolock = { 1592 .llseek = gfs2_llseek, 1593 .read_iter = gfs2_file_read_iter, 1594 .write_iter = gfs2_file_write_iter, 1595 .iopoll = iocb_bio_iopoll, 1596 .unlocked_ioctl = gfs2_ioctl, 1597 .compat_ioctl = gfs2_compat_ioctl, 1598 .mmap = gfs2_mmap, 1599 .open = gfs2_open, 1600 .release = gfs2_release, 1601 .fsync = gfs2_fsync, 1602 .splice_read = generic_file_splice_read, 1603 .splice_write = gfs2_file_splice_write, 1604 .setlease = generic_setlease, 1605 .fallocate = gfs2_fallocate, 1606 }; 1607 1608 const struct file_operations gfs2_dir_fops_nolock = { 1609 .iterate_shared = gfs2_readdir, 1610 .unlocked_ioctl = gfs2_ioctl, 1611 .compat_ioctl = gfs2_compat_ioctl, 1612 .open = gfs2_open, 1613 .release = gfs2_release, 1614 .fsync = gfs2_fsync, 1615 .llseek = default_llseek, 1616 }; 1617 1618