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/falloc.h> 22 #include <linux/swap.h> 23 #include <linux/crc32.h> 24 #include <linux/writeback.h> 25 #include <asm/uaccess.h> 26 #include <linux/dlm.h> 27 #include <linux/dlm_plock.h> 28 #include <linux/aio.h> 29 30 #include "gfs2.h" 31 #include "incore.h" 32 #include "bmap.h" 33 #include "dir.h" 34 #include "glock.h" 35 #include "glops.h" 36 #include "inode.h" 37 #include "log.h" 38 #include "meta_io.h" 39 #include "quota.h" 40 #include "rgrp.h" 41 #include "trans.h" 42 #include "util.h" 43 44 /** 45 * gfs2_llseek - seek to a location in a file 46 * @file: the file 47 * @offset: the offset 48 * @whence: Where to seek from (SEEK_SET, SEEK_CUR, or SEEK_END) 49 * 50 * SEEK_END requires the glock for the file because it references the 51 * file's size. 52 * 53 * Returns: The new offset, or errno 54 */ 55 56 static loff_t gfs2_llseek(struct file *file, loff_t offset, int whence) 57 { 58 struct gfs2_inode *ip = GFS2_I(file->f_mapping->host); 59 struct gfs2_holder i_gh; 60 loff_t error; 61 62 switch (whence) { 63 case SEEK_END: /* These reference inode->i_size */ 64 case SEEK_DATA: 65 case SEEK_HOLE: 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 case SEEK_CUR: 74 case SEEK_SET: 75 error = generic_file_llseek(file, offset, whence); 76 break; 77 default: 78 error = -EINVAL; 79 } 80 81 return error; 82 } 83 84 /** 85 * gfs2_readdir - Iterator for a directory 86 * @file: The directory to read from 87 * @ctx: What to feed directory entries to 88 * 89 * Returns: errno 90 */ 91 92 static int gfs2_readdir(struct file *file, struct dir_context *ctx) 93 { 94 struct inode *dir = file->f_mapping->host; 95 struct gfs2_inode *dip = GFS2_I(dir); 96 struct gfs2_holder d_gh; 97 int error; 98 99 error = gfs2_glock_nq_init(dip->i_gl, LM_ST_SHARED, 0, &d_gh); 100 if (error) 101 return error; 102 103 error = gfs2_dir_read(dir, ctx, &file->f_ra); 104 105 gfs2_glock_dq_uninit(&d_gh); 106 107 return error; 108 } 109 110 /** 111 * fsflags_cvt 112 * @table: A table of 32 u32 flags 113 * @val: a 32 bit value to convert 114 * 115 * This function can be used to convert between fsflags values and 116 * GFS2's own flags values. 117 * 118 * Returns: the converted flags 119 */ 120 static u32 fsflags_cvt(const u32 *table, u32 val) 121 { 122 u32 res = 0; 123 while(val) { 124 if (val & 1) 125 res |= *table; 126 table++; 127 val >>= 1; 128 } 129 return res; 130 } 131 132 static const u32 fsflags_to_gfs2[32] = { 133 [3] = GFS2_DIF_SYNC, 134 [4] = GFS2_DIF_IMMUTABLE, 135 [5] = GFS2_DIF_APPENDONLY, 136 [7] = GFS2_DIF_NOATIME, 137 [12] = GFS2_DIF_EXHASH, 138 [14] = GFS2_DIF_INHERIT_JDATA, 139 [17] = GFS2_DIF_TOPDIR, 140 }; 141 142 static const u32 gfs2_to_fsflags[32] = { 143 [gfs2fl_Sync] = FS_SYNC_FL, 144 [gfs2fl_Immutable] = FS_IMMUTABLE_FL, 145 [gfs2fl_AppendOnly] = FS_APPEND_FL, 146 [gfs2fl_NoAtime] = FS_NOATIME_FL, 147 [gfs2fl_ExHash] = FS_INDEX_FL, 148 [gfs2fl_TopLevel] = FS_TOPDIR_FL, 149 [gfs2fl_InheritJdata] = FS_JOURNAL_DATA_FL, 150 }; 151 152 static int gfs2_get_flags(struct file *filp, u32 __user *ptr) 153 { 154 struct inode *inode = file_inode(filp); 155 struct gfs2_inode *ip = GFS2_I(inode); 156 struct gfs2_holder gh; 157 int error; 158 u32 fsflags; 159 160 gfs2_holder_init(ip->i_gl, LM_ST_SHARED, 0, &gh); 161 error = gfs2_glock_nq(&gh); 162 if (error) 163 return error; 164 165 fsflags = fsflags_cvt(gfs2_to_fsflags, ip->i_diskflags); 166 if (!S_ISDIR(inode->i_mode) && ip->i_diskflags & GFS2_DIF_JDATA) 167 fsflags |= FS_JOURNAL_DATA_FL; 168 if (put_user(fsflags, ptr)) 169 error = -EFAULT; 170 171 gfs2_glock_dq(&gh); 172 gfs2_holder_uninit(&gh); 173 return error; 174 } 175 176 void gfs2_set_inode_flags(struct inode *inode) 177 { 178 struct gfs2_inode *ip = GFS2_I(inode); 179 unsigned int flags = inode->i_flags; 180 181 flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC|S_NOSEC); 182 if ((ip->i_eattr == 0) && !is_sxid(inode->i_mode)) 183 inode->i_flags |= S_NOSEC; 184 if (ip->i_diskflags & GFS2_DIF_IMMUTABLE) 185 flags |= S_IMMUTABLE; 186 if (ip->i_diskflags & GFS2_DIF_APPENDONLY) 187 flags |= S_APPEND; 188 if (ip->i_diskflags & GFS2_DIF_NOATIME) 189 flags |= S_NOATIME; 190 if (ip->i_diskflags & GFS2_DIF_SYNC) 191 flags |= S_SYNC; 192 inode->i_flags = flags; 193 } 194 195 /* Flags that can be set by user space */ 196 #define GFS2_FLAGS_USER_SET (GFS2_DIF_JDATA| \ 197 GFS2_DIF_IMMUTABLE| \ 198 GFS2_DIF_APPENDONLY| \ 199 GFS2_DIF_NOATIME| \ 200 GFS2_DIF_SYNC| \ 201 GFS2_DIF_SYSTEM| \ 202 GFS2_DIF_TOPDIR| \ 203 GFS2_DIF_INHERIT_JDATA) 204 205 /** 206 * gfs2_set_flags - set flags on an inode 207 * @inode: The inode 208 * @flags: The flags to set 209 * @mask: Indicates which flags are valid 210 * 211 */ 212 static int do_gfs2_set_flags(struct file *filp, u32 reqflags, u32 mask) 213 { 214 struct inode *inode = file_inode(filp); 215 struct gfs2_inode *ip = GFS2_I(inode); 216 struct gfs2_sbd *sdp = GFS2_SB(inode); 217 struct buffer_head *bh; 218 struct gfs2_holder gh; 219 int error; 220 u32 new_flags, flags; 221 222 error = mnt_want_write_file(filp); 223 if (error) 224 return error; 225 226 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh); 227 if (error) 228 goto out_drop_write; 229 230 error = -EACCES; 231 if (!inode_owner_or_capable(inode)) 232 goto out; 233 234 error = 0; 235 flags = ip->i_diskflags; 236 new_flags = (flags & ~mask) | (reqflags & mask); 237 if ((new_flags ^ flags) == 0) 238 goto out; 239 240 error = -EINVAL; 241 if ((new_flags ^ flags) & ~GFS2_FLAGS_USER_SET) 242 goto out; 243 244 error = -EPERM; 245 if (IS_IMMUTABLE(inode) && (new_flags & GFS2_DIF_IMMUTABLE)) 246 goto out; 247 if (IS_APPEND(inode) && (new_flags & GFS2_DIF_APPENDONLY)) 248 goto out; 249 if (((new_flags ^ flags) & GFS2_DIF_IMMUTABLE) && 250 !capable(CAP_LINUX_IMMUTABLE)) 251 goto out; 252 if (!IS_IMMUTABLE(inode)) { 253 error = gfs2_permission(inode, MAY_WRITE); 254 if (error) 255 goto out; 256 } 257 if ((flags ^ new_flags) & GFS2_DIF_JDATA) { 258 if (flags & GFS2_DIF_JDATA) 259 gfs2_log_flush(sdp, ip->i_gl); 260 error = filemap_fdatawrite(inode->i_mapping); 261 if (error) 262 goto out; 263 error = filemap_fdatawait(inode->i_mapping); 264 if (error) 265 goto out; 266 } 267 error = gfs2_trans_begin(sdp, RES_DINODE, 0); 268 if (error) 269 goto out; 270 error = gfs2_meta_inode_buffer(ip, &bh); 271 if (error) 272 goto out_trans_end; 273 gfs2_trans_add_meta(ip->i_gl, bh); 274 ip->i_diskflags = new_flags; 275 gfs2_dinode_out(ip, bh->b_data); 276 brelse(bh); 277 gfs2_set_inode_flags(inode); 278 gfs2_set_aops(inode); 279 out_trans_end: 280 gfs2_trans_end(sdp); 281 out: 282 gfs2_glock_dq_uninit(&gh); 283 out_drop_write: 284 mnt_drop_write_file(filp); 285 return error; 286 } 287 288 static int gfs2_set_flags(struct file *filp, u32 __user *ptr) 289 { 290 struct inode *inode = file_inode(filp); 291 u32 fsflags, gfsflags; 292 293 if (get_user(fsflags, ptr)) 294 return -EFAULT; 295 296 gfsflags = fsflags_cvt(fsflags_to_gfs2, fsflags); 297 if (!S_ISDIR(inode->i_mode)) { 298 gfsflags &= ~GFS2_DIF_TOPDIR; 299 if (gfsflags & GFS2_DIF_INHERIT_JDATA) 300 gfsflags ^= (GFS2_DIF_JDATA | GFS2_DIF_INHERIT_JDATA); 301 return do_gfs2_set_flags(filp, gfsflags, ~0); 302 } 303 return do_gfs2_set_flags(filp, gfsflags, ~GFS2_DIF_JDATA); 304 } 305 306 static long gfs2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) 307 { 308 switch(cmd) { 309 case FS_IOC_GETFLAGS: 310 return gfs2_get_flags(filp, (u32 __user *)arg); 311 case FS_IOC_SETFLAGS: 312 return gfs2_set_flags(filp, (u32 __user *)arg); 313 case FITRIM: 314 return gfs2_fitrim(filp, (void __user *)arg); 315 } 316 return -ENOTTY; 317 } 318 319 /** 320 * gfs2_size_hint - Give a hint to the size of a write request 321 * @file: The struct file 322 * @offset: The file offset of the write 323 * @size: The length of the write 324 * 325 * When we are about to do a write, this function records the total 326 * write size in order to provide a suitable hint to the lower layers 327 * about how many blocks will be required. 328 * 329 */ 330 331 static void gfs2_size_hint(struct file *filep, loff_t offset, size_t size) 332 { 333 struct inode *inode = file_inode(filep); 334 struct gfs2_sbd *sdp = GFS2_SB(inode); 335 struct gfs2_inode *ip = GFS2_I(inode); 336 size_t blks = (size + sdp->sd_sb.sb_bsize - 1) >> sdp->sd_sb.sb_bsize_shift; 337 int hint = min_t(size_t, INT_MAX, blks); 338 339 atomic_set(&ip->i_res->rs_sizehint, hint); 340 } 341 342 /** 343 * gfs2_allocate_page_backing - Use bmap to allocate blocks 344 * @page: The (locked) page to allocate backing for 345 * 346 * We try to allocate all the blocks required for the page in 347 * one go. This might fail for various reasons, so we keep 348 * trying until all the blocks to back this page are allocated. 349 * If some of the blocks are already allocated, thats ok too. 350 */ 351 352 static int gfs2_allocate_page_backing(struct page *page) 353 { 354 struct inode *inode = page->mapping->host; 355 struct buffer_head bh; 356 unsigned long size = PAGE_CACHE_SIZE; 357 u64 lblock = page->index << (PAGE_CACHE_SHIFT - inode->i_blkbits); 358 359 do { 360 bh.b_state = 0; 361 bh.b_size = size; 362 gfs2_block_map(inode, lblock, &bh, 1); 363 if (!buffer_mapped(&bh)) 364 return -EIO; 365 size -= bh.b_size; 366 lblock += (bh.b_size >> inode->i_blkbits); 367 } while(size > 0); 368 return 0; 369 } 370 371 /** 372 * gfs2_page_mkwrite - Make a shared, mmap()ed, page writable 373 * @vma: The virtual memory area 374 * @page: The page which is about to become writable 375 * 376 * When the page becomes writable, we need to ensure that we have 377 * blocks allocated on disk to back that page. 378 */ 379 380 static int gfs2_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf) 381 { 382 struct page *page = vmf->page; 383 struct inode *inode = file_inode(vma->vm_file); 384 struct gfs2_inode *ip = GFS2_I(inode); 385 struct gfs2_sbd *sdp = GFS2_SB(inode); 386 unsigned long last_index; 387 u64 pos = page->index << PAGE_CACHE_SHIFT; 388 unsigned int data_blocks, ind_blocks, rblocks; 389 struct gfs2_holder gh; 390 loff_t size; 391 int ret; 392 393 sb_start_pagefault(inode->i_sb); 394 395 /* Update file times before taking page lock */ 396 file_update_time(vma->vm_file); 397 398 ret = get_write_access(inode); 399 if (ret) 400 goto out; 401 402 ret = gfs2_rs_alloc(ip); 403 if (ret) 404 goto out_write_access; 405 406 gfs2_size_hint(vma->vm_file, pos, PAGE_CACHE_SIZE); 407 408 gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh); 409 ret = gfs2_glock_nq(&gh); 410 if (ret) 411 goto out_uninit; 412 413 set_bit(GLF_DIRTY, &ip->i_gl->gl_flags); 414 set_bit(GIF_SW_PAGED, &ip->i_flags); 415 416 if (!gfs2_write_alloc_required(ip, pos, PAGE_CACHE_SIZE)) { 417 lock_page(page); 418 if (!PageUptodate(page) || page->mapping != inode->i_mapping) { 419 ret = -EAGAIN; 420 unlock_page(page); 421 } 422 goto out_unlock; 423 } 424 425 ret = gfs2_rindex_update(sdp); 426 if (ret) 427 goto out_unlock; 428 429 ret = gfs2_quota_lock_check(ip); 430 if (ret) 431 goto out_unlock; 432 gfs2_write_calc_reserv(ip, PAGE_CACHE_SIZE, &data_blocks, &ind_blocks); 433 ret = gfs2_inplace_reserve(ip, data_blocks + ind_blocks, 0); 434 if (ret) 435 goto out_quota_unlock; 436 437 rblocks = RES_DINODE + ind_blocks; 438 if (gfs2_is_jdata(ip)) 439 rblocks += data_blocks ? data_blocks : 1; 440 if (ind_blocks || data_blocks) { 441 rblocks += RES_STATFS + RES_QUOTA; 442 rblocks += gfs2_rg_blocks(ip, data_blocks + ind_blocks); 443 } 444 ret = gfs2_trans_begin(sdp, rblocks, 0); 445 if (ret) 446 goto out_trans_fail; 447 448 lock_page(page); 449 ret = -EINVAL; 450 size = i_size_read(inode); 451 last_index = (size - 1) >> PAGE_CACHE_SHIFT; 452 /* Check page index against inode size */ 453 if (size == 0 || (page->index > last_index)) 454 goto out_trans_end; 455 456 ret = -EAGAIN; 457 /* If truncated, we must retry the operation, we may have raced 458 * with the glock demotion code. 459 */ 460 if (!PageUptodate(page) || page->mapping != inode->i_mapping) 461 goto out_trans_end; 462 463 /* Unstuff, if required, and allocate backing blocks for page */ 464 ret = 0; 465 if (gfs2_is_stuffed(ip)) 466 ret = gfs2_unstuff_dinode(ip, page); 467 if (ret == 0) 468 ret = gfs2_allocate_page_backing(page); 469 470 out_trans_end: 471 if (ret) 472 unlock_page(page); 473 gfs2_trans_end(sdp); 474 out_trans_fail: 475 gfs2_inplace_release(ip); 476 out_quota_unlock: 477 gfs2_quota_unlock(ip); 478 out_unlock: 479 gfs2_glock_dq(&gh); 480 out_uninit: 481 gfs2_holder_uninit(&gh); 482 if (ret == 0) { 483 set_page_dirty(page); 484 wait_for_stable_page(page); 485 } 486 out_write_access: 487 put_write_access(inode); 488 out: 489 sb_end_pagefault(inode->i_sb); 490 return block_page_mkwrite_return(ret); 491 } 492 493 static const struct vm_operations_struct gfs2_vm_ops = { 494 .fault = filemap_fault, 495 .page_mkwrite = gfs2_page_mkwrite, 496 .remap_pages = generic_file_remap_pages, 497 }; 498 499 /** 500 * gfs2_mmap - 501 * @file: The file to map 502 * @vma: The VMA which described the mapping 503 * 504 * There is no need to get a lock here unless we should be updating 505 * atime. We ignore any locking errors since the only consequence is 506 * a missed atime update (which will just be deferred until later). 507 * 508 * Returns: 0 509 */ 510 511 static int gfs2_mmap(struct file *file, struct vm_area_struct *vma) 512 { 513 struct gfs2_inode *ip = GFS2_I(file->f_mapping->host); 514 515 if (!(file->f_flags & O_NOATIME) && 516 !IS_NOATIME(&ip->i_inode)) { 517 struct gfs2_holder i_gh; 518 int error; 519 520 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, 521 &i_gh); 522 if (error) 523 return error; 524 /* grab lock to update inode */ 525 gfs2_glock_dq_uninit(&i_gh); 526 file_accessed(file); 527 } 528 vma->vm_ops = &gfs2_vm_ops; 529 530 return 0; 531 } 532 533 /** 534 * gfs2_open_common - This is common to open and atomic_open 535 * @inode: The inode being opened 536 * @file: The file being opened 537 * 538 * This maybe called under a glock or not depending upon how it has 539 * been called. We must always be called under a glock for regular 540 * files, however. For other file types, it does not matter whether 541 * we hold the glock or not. 542 * 543 * Returns: Error code or 0 for success 544 */ 545 546 int gfs2_open_common(struct inode *inode, struct file *file) 547 { 548 struct gfs2_file *fp; 549 int ret; 550 551 if (S_ISREG(inode->i_mode)) { 552 ret = generic_file_open(inode, file); 553 if (ret) 554 return ret; 555 } 556 557 fp = kzalloc(sizeof(struct gfs2_file), GFP_NOFS); 558 if (!fp) 559 return -ENOMEM; 560 561 mutex_init(&fp->f_fl_mutex); 562 563 gfs2_assert_warn(GFS2_SB(inode), !file->private_data); 564 file->private_data = fp; 565 return 0; 566 } 567 568 /** 569 * gfs2_open - open a file 570 * @inode: the inode to open 571 * @file: the struct file for this opening 572 * 573 * After atomic_open, this function is only used for opening files 574 * which are already cached. We must still get the glock for regular 575 * files to ensure that we have the file size uptodate for the large 576 * file check which is in the common code. That is only an issue for 577 * regular files though. 578 * 579 * Returns: errno 580 */ 581 582 static int gfs2_open(struct inode *inode, struct file *file) 583 { 584 struct gfs2_inode *ip = GFS2_I(inode); 585 struct gfs2_holder i_gh; 586 int error; 587 bool need_unlock = false; 588 589 if (S_ISREG(ip->i_inode.i_mode)) { 590 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, 591 &i_gh); 592 if (error) 593 return error; 594 need_unlock = true; 595 } 596 597 error = gfs2_open_common(inode, file); 598 599 if (need_unlock) 600 gfs2_glock_dq_uninit(&i_gh); 601 602 return error; 603 } 604 605 /** 606 * gfs2_release - called to close a struct file 607 * @inode: the inode the struct file belongs to 608 * @file: the struct file being closed 609 * 610 * Returns: errno 611 */ 612 613 static int gfs2_release(struct inode *inode, struct file *file) 614 { 615 struct gfs2_inode *ip = GFS2_I(inode); 616 617 kfree(file->private_data); 618 file->private_data = NULL; 619 620 if (!(file->f_mode & FMODE_WRITE)) 621 return 0; 622 623 gfs2_rs_delete(ip); 624 return 0; 625 } 626 627 /** 628 * gfs2_fsync - sync the dirty data for a file (across the cluster) 629 * @file: the file that points to the dentry 630 * @start: the start position in the file to sync 631 * @end: the end position in the file to sync 632 * @datasync: set if we can ignore timestamp changes 633 * 634 * We split the data flushing here so that we don't wait for the data 635 * until after we've also sent the metadata to disk. Note that for 636 * data=ordered, we will write & wait for the data at the log flush 637 * stage anyway, so this is unlikely to make much of a difference 638 * except in the data=writeback case. 639 * 640 * If the fdatawrite fails due to any reason except -EIO, we will 641 * continue the remainder of the fsync, although we'll still report 642 * the error at the end. This is to match filemap_write_and_wait_range() 643 * behaviour. 644 * 645 * Returns: errno 646 */ 647 648 static int gfs2_fsync(struct file *file, loff_t start, loff_t end, 649 int datasync) 650 { 651 struct address_space *mapping = file->f_mapping; 652 struct inode *inode = mapping->host; 653 int sync_state = inode->i_state & I_DIRTY; 654 struct gfs2_inode *ip = GFS2_I(inode); 655 int ret = 0, ret1 = 0; 656 657 if (mapping->nrpages) { 658 ret1 = filemap_fdatawrite_range(mapping, start, end); 659 if (ret1 == -EIO) 660 return ret1; 661 } 662 663 if (!gfs2_is_jdata(ip)) 664 sync_state &= ~I_DIRTY_PAGES; 665 if (datasync) 666 sync_state &= ~I_DIRTY_SYNC; 667 668 if (sync_state) { 669 ret = sync_inode_metadata(inode, 1); 670 if (ret) 671 return ret; 672 if (gfs2_is_jdata(ip)) 673 filemap_write_and_wait(mapping); 674 gfs2_ail_flush(ip->i_gl, 1); 675 } 676 677 if (mapping->nrpages) 678 ret = filemap_fdatawait_range(mapping, start, end); 679 680 return ret ? ret : ret1; 681 } 682 683 /** 684 * gfs2_file_aio_write - Perform a write to a file 685 * @iocb: The io context 686 * @iov: The data to write 687 * @nr_segs: Number of @iov segments 688 * @pos: The file position 689 * 690 * We have to do a lock/unlock here to refresh the inode size for 691 * O_APPEND writes, otherwise we can land up writing at the wrong 692 * offset. There is still a race, but provided the app is using its 693 * own file locking, this will make O_APPEND work as expected. 694 * 695 */ 696 697 static ssize_t gfs2_file_aio_write(struct kiocb *iocb, const struct iovec *iov, 698 unsigned long nr_segs, loff_t pos) 699 { 700 struct file *file = iocb->ki_filp; 701 size_t writesize = iov_length(iov, nr_segs); 702 struct gfs2_inode *ip = GFS2_I(file_inode(file)); 703 int ret; 704 705 ret = gfs2_rs_alloc(ip); 706 if (ret) 707 return ret; 708 709 gfs2_size_hint(file, pos, writesize); 710 711 if (file->f_flags & O_APPEND) { 712 struct gfs2_holder gh; 713 714 ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &gh); 715 if (ret) 716 return ret; 717 gfs2_glock_dq_uninit(&gh); 718 } 719 720 return generic_file_aio_write(iocb, iov, nr_segs, pos); 721 } 722 723 static int fallocate_chunk(struct inode *inode, loff_t offset, loff_t len, 724 int mode) 725 { 726 struct gfs2_inode *ip = GFS2_I(inode); 727 struct buffer_head *dibh; 728 int error; 729 loff_t size = len; 730 unsigned int nr_blks; 731 sector_t lblock = offset >> inode->i_blkbits; 732 733 error = gfs2_meta_inode_buffer(ip, &dibh); 734 if (unlikely(error)) 735 return error; 736 737 gfs2_trans_add_meta(ip->i_gl, dibh); 738 739 if (gfs2_is_stuffed(ip)) { 740 error = gfs2_unstuff_dinode(ip, NULL); 741 if (unlikely(error)) 742 goto out; 743 } 744 745 while (len) { 746 struct buffer_head bh_map = { .b_state = 0, .b_blocknr = 0 }; 747 bh_map.b_size = len; 748 set_buffer_zeronew(&bh_map); 749 750 error = gfs2_block_map(inode, lblock, &bh_map, 1); 751 if (unlikely(error)) 752 goto out; 753 len -= bh_map.b_size; 754 nr_blks = bh_map.b_size >> inode->i_blkbits; 755 lblock += nr_blks; 756 if (!buffer_new(&bh_map)) 757 continue; 758 if (unlikely(!buffer_zeronew(&bh_map))) { 759 error = -EIO; 760 goto out; 761 } 762 } 763 if (offset + size > inode->i_size && !(mode & FALLOC_FL_KEEP_SIZE)) 764 i_size_write(inode, offset + size); 765 766 mark_inode_dirty(inode); 767 768 out: 769 brelse(dibh); 770 return error; 771 } 772 773 static void calc_max_reserv(struct gfs2_inode *ip, loff_t max, loff_t *len, 774 unsigned int *data_blocks, unsigned int *ind_blocks) 775 { 776 const struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode); 777 unsigned int max_blocks = ip->i_rgd->rd_free_clone; 778 unsigned int tmp, max_data = max_blocks - 3 * (sdp->sd_max_height - 1); 779 780 for (tmp = max_data; tmp > sdp->sd_diptrs;) { 781 tmp = DIV_ROUND_UP(tmp, sdp->sd_inptrs); 782 max_data -= tmp; 783 } 784 /* This calculation isn't the exact reverse of gfs2_write_calc_reserve, 785 so it might end up with fewer data blocks */ 786 if (max_data <= *data_blocks) 787 return; 788 *data_blocks = max_data; 789 *ind_blocks = max_blocks - max_data; 790 *len = ((loff_t)max_data - 3) << sdp->sd_sb.sb_bsize_shift; 791 if (*len > max) { 792 *len = max; 793 gfs2_write_calc_reserv(ip, max, data_blocks, ind_blocks); 794 } 795 } 796 797 static long gfs2_fallocate(struct file *file, int mode, loff_t offset, 798 loff_t len) 799 { 800 struct inode *inode = file_inode(file); 801 struct gfs2_sbd *sdp = GFS2_SB(inode); 802 struct gfs2_inode *ip = GFS2_I(inode); 803 unsigned int data_blocks = 0, ind_blocks = 0, rblocks; 804 loff_t bytes, max_bytes; 805 int error; 806 const loff_t pos = offset; 807 const loff_t count = len; 808 loff_t bsize_mask = ~((loff_t)sdp->sd_sb.sb_bsize - 1); 809 loff_t next = (offset + len - 1) >> sdp->sd_sb.sb_bsize_shift; 810 loff_t max_chunk_size = UINT_MAX & bsize_mask; 811 next = (next + 1) << sdp->sd_sb.sb_bsize_shift; 812 813 /* We only support the FALLOC_FL_KEEP_SIZE mode */ 814 if (mode & ~FALLOC_FL_KEEP_SIZE) 815 return -EOPNOTSUPP; 816 817 offset &= bsize_mask; 818 819 len = next - offset; 820 bytes = sdp->sd_max_rg_data * sdp->sd_sb.sb_bsize / 2; 821 if (!bytes) 822 bytes = UINT_MAX; 823 bytes &= bsize_mask; 824 if (bytes == 0) 825 bytes = sdp->sd_sb.sb_bsize; 826 827 error = gfs2_rs_alloc(ip); 828 if (error) 829 return error; 830 831 gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &ip->i_gh); 832 error = gfs2_glock_nq(&ip->i_gh); 833 if (unlikely(error)) 834 goto out_uninit; 835 836 gfs2_size_hint(file, offset, len); 837 838 while (len > 0) { 839 if (len < bytes) 840 bytes = len; 841 if (!gfs2_write_alloc_required(ip, offset, bytes)) { 842 len -= bytes; 843 offset += bytes; 844 continue; 845 } 846 error = gfs2_quota_lock_check(ip); 847 if (error) 848 goto out_unlock; 849 850 retry: 851 gfs2_write_calc_reserv(ip, bytes, &data_blocks, &ind_blocks); 852 853 error = gfs2_inplace_reserve(ip, data_blocks + ind_blocks, 0); 854 if (error) { 855 if (error == -ENOSPC && bytes > sdp->sd_sb.sb_bsize) { 856 bytes >>= 1; 857 bytes &= bsize_mask; 858 if (bytes == 0) 859 bytes = sdp->sd_sb.sb_bsize; 860 goto retry; 861 } 862 goto out_qunlock; 863 } 864 max_bytes = bytes; 865 calc_max_reserv(ip, (len > max_chunk_size)? max_chunk_size: len, 866 &max_bytes, &data_blocks, &ind_blocks); 867 868 rblocks = RES_DINODE + ind_blocks + RES_STATFS + RES_QUOTA + 869 RES_RG_HDR + gfs2_rg_blocks(ip, data_blocks + ind_blocks); 870 if (gfs2_is_jdata(ip)) 871 rblocks += data_blocks ? data_blocks : 1; 872 873 error = gfs2_trans_begin(sdp, rblocks, 874 PAGE_CACHE_SIZE/sdp->sd_sb.sb_bsize); 875 if (error) 876 goto out_trans_fail; 877 878 error = fallocate_chunk(inode, offset, max_bytes, mode); 879 gfs2_trans_end(sdp); 880 881 if (error) 882 goto out_trans_fail; 883 884 len -= max_bytes; 885 offset += max_bytes; 886 gfs2_inplace_release(ip); 887 gfs2_quota_unlock(ip); 888 } 889 890 if (error == 0) 891 error = generic_write_sync(file, pos, count); 892 goto out_unlock; 893 894 out_trans_fail: 895 gfs2_inplace_release(ip); 896 out_qunlock: 897 gfs2_quota_unlock(ip); 898 out_unlock: 899 gfs2_glock_dq(&ip->i_gh); 900 out_uninit: 901 gfs2_holder_uninit(&ip->i_gh); 902 return error; 903 } 904 905 #ifdef CONFIG_GFS2_FS_LOCKING_DLM 906 907 /** 908 * gfs2_setlease - acquire/release a file lease 909 * @file: the file pointer 910 * @arg: lease type 911 * @fl: file lock 912 * 913 * We don't currently have a way to enforce a lease across the whole 914 * cluster; until we do, disable leases (by just returning -EINVAL), 915 * unless the administrator has requested purely local locking. 916 * 917 * Locking: called under i_lock 918 * 919 * Returns: errno 920 */ 921 922 static int gfs2_setlease(struct file *file, long arg, struct file_lock **fl) 923 { 924 return -EINVAL; 925 } 926 927 /** 928 * gfs2_lock - acquire/release a posix lock on a file 929 * @file: the file pointer 930 * @cmd: either modify or retrieve lock state, possibly wait 931 * @fl: type and range of lock 932 * 933 * Returns: errno 934 */ 935 936 static int gfs2_lock(struct file *file, int cmd, struct file_lock *fl) 937 { 938 struct gfs2_inode *ip = GFS2_I(file->f_mapping->host); 939 struct gfs2_sbd *sdp = GFS2_SB(file->f_mapping->host); 940 struct lm_lockstruct *ls = &sdp->sd_lockstruct; 941 942 if (!(fl->fl_flags & FL_POSIX)) 943 return -ENOLCK; 944 if (__mandatory_lock(&ip->i_inode) && fl->fl_type != F_UNLCK) 945 return -ENOLCK; 946 947 if (cmd == F_CANCELLK) { 948 /* Hack: */ 949 cmd = F_SETLK; 950 fl->fl_type = F_UNLCK; 951 } 952 if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags))) { 953 if (fl->fl_type == F_UNLCK) 954 posix_lock_file_wait(file, fl); 955 return -EIO; 956 } 957 if (IS_GETLK(cmd)) 958 return dlm_posix_get(ls->ls_dlm, ip->i_no_addr, file, fl); 959 else if (fl->fl_type == F_UNLCK) 960 return dlm_posix_unlock(ls->ls_dlm, ip->i_no_addr, file, fl); 961 else 962 return dlm_posix_lock(ls->ls_dlm, ip->i_no_addr, file, cmd, fl); 963 } 964 965 static int do_flock(struct file *file, int cmd, struct file_lock *fl) 966 { 967 struct gfs2_file *fp = file->private_data; 968 struct gfs2_holder *fl_gh = &fp->f_fl_gh; 969 struct gfs2_inode *ip = GFS2_I(file_inode(file)); 970 struct gfs2_glock *gl; 971 unsigned int state; 972 int flags; 973 int error = 0; 974 975 state = (fl->fl_type == F_WRLCK) ? LM_ST_EXCLUSIVE : LM_ST_SHARED; 976 flags = (IS_SETLKW(cmd) ? 0 : LM_FLAG_TRY) | GL_EXACT | GL_NOCACHE; 977 978 mutex_lock(&fp->f_fl_mutex); 979 980 gl = fl_gh->gh_gl; 981 if (gl) { 982 if (fl_gh->gh_state == state) 983 goto out; 984 flock_lock_file_wait(file, 985 &(struct file_lock){.fl_type = F_UNLCK}); 986 gfs2_glock_dq_wait(fl_gh); 987 gfs2_holder_reinit(state, flags, fl_gh); 988 } else { 989 error = gfs2_glock_get(GFS2_SB(&ip->i_inode), ip->i_no_addr, 990 &gfs2_flock_glops, CREATE, &gl); 991 if (error) 992 goto out; 993 gfs2_holder_init(gl, state, flags, fl_gh); 994 gfs2_glock_put(gl); 995 } 996 error = gfs2_glock_nq(fl_gh); 997 if (error) { 998 gfs2_holder_uninit(fl_gh); 999 if (error == GLR_TRYFAILED) 1000 error = -EAGAIN; 1001 } else { 1002 error = flock_lock_file_wait(file, fl); 1003 gfs2_assert_warn(GFS2_SB(&ip->i_inode), !error); 1004 } 1005 1006 out: 1007 mutex_unlock(&fp->f_fl_mutex); 1008 return error; 1009 } 1010 1011 static void do_unflock(struct file *file, struct file_lock *fl) 1012 { 1013 struct gfs2_file *fp = file->private_data; 1014 struct gfs2_holder *fl_gh = &fp->f_fl_gh; 1015 1016 mutex_lock(&fp->f_fl_mutex); 1017 flock_lock_file_wait(file, fl); 1018 if (fl_gh->gh_gl) { 1019 gfs2_glock_dq_wait(fl_gh); 1020 gfs2_holder_uninit(fl_gh); 1021 } 1022 mutex_unlock(&fp->f_fl_mutex); 1023 } 1024 1025 /** 1026 * gfs2_flock - acquire/release a flock lock on a file 1027 * @file: the file pointer 1028 * @cmd: either modify or retrieve lock state, possibly wait 1029 * @fl: type and range of lock 1030 * 1031 * Returns: errno 1032 */ 1033 1034 static int gfs2_flock(struct file *file, int cmd, struct file_lock *fl) 1035 { 1036 if (!(fl->fl_flags & FL_FLOCK)) 1037 return -ENOLCK; 1038 if (fl->fl_type & LOCK_MAND) 1039 return -EOPNOTSUPP; 1040 1041 if (fl->fl_type == F_UNLCK) { 1042 do_unflock(file, fl); 1043 return 0; 1044 } else { 1045 return do_flock(file, cmd, fl); 1046 } 1047 } 1048 1049 const struct file_operations gfs2_file_fops = { 1050 .llseek = gfs2_llseek, 1051 .read = do_sync_read, 1052 .aio_read = generic_file_aio_read, 1053 .write = do_sync_write, 1054 .aio_write = gfs2_file_aio_write, 1055 .unlocked_ioctl = gfs2_ioctl, 1056 .mmap = gfs2_mmap, 1057 .open = gfs2_open, 1058 .release = gfs2_release, 1059 .fsync = gfs2_fsync, 1060 .lock = gfs2_lock, 1061 .flock = gfs2_flock, 1062 .splice_read = generic_file_splice_read, 1063 .splice_write = generic_file_splice_write, 1064 .setlease = gfs2_setlease, 1065 .fallocate = gfs2_fallocate, 1066 }; 1067 1068 const struct file_operations gfs2_dir_fops = { 1069 .iterate = gfs2_readdir, 1070 .unlocked_ioctl = gfs2_ioctl, 1071 .open = gfs2_open, 1072 .release = gfs2_release, 1073 .fsync = gfs2_fsync, 1074 .lock = gfs2_lock, 1075 .flock = gfs2_flock, 1076 .llseek = default_llseek, 1077 }; 1078 1079 #endif /* CONFIG_GFS2_FS_LOCKING_DLM */ 1080 1081 const struct file_operations gfs2_file_fops_nolock = { 1082 .llseek = gfs2_llseek, 1083 .read = do_sync_read, 1084 .aio_read = generic_file_aio_read, 1085 .write = do_sync_write, 1086 .aio_write = gfs2_file_aio_write, 1087 .unlocked_ioctl = gfs2_ioctl, 1088 .mmap = gfs2_mmap, 1089 .open = gfs2_open, 1090 .release = gfs2_release, 1091 .fsync = gfs2_fsync, 1092 .splice_read = generic_file_splice_read, 1093 .splice_write = generic_file_splice_write, 1094 .setlease = generic_setlease, 1095 .fallocate = gfs2_fallocate, 1096 }; 1097 1098 const struct file_operations gfs2_dir_fops_nolock = { 1099 .iterate = gfs2_readdir, 1100 .unlocked_ioctl = gfs2_ioctl, 1101 .open = gfs2_open, 1102 .release = gfs2_release, 1103 .fsync = gfs2_fsync, 1104 .llseek = default_llseek, 1105 }; 1106 1107