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/delay.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 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 * do_gfs2_set_flags - set flags on an inode 207 * @filp: file pointer 208 * @reqflags: 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, NORMAL_FLUSH); 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 * @filep: 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 if (hint > atomic_read(&ip->i_res->rs_sizehint)) 340 atomic_set(&ip->i_res->rs_sizehint, hint); 341 } 342 343 /** 344 * gfs2_allocate_page_backing - Use bmap to allocate blocks 345 * @page: The (locked) page to allocate backing for 346 * 347 * We try to allocate all the blocks required for the page in 348 * one go. This might fail for various reasons, so we keep 349 * trying until all the blocks to back this page are allocated. 350 * If some of the blocks are already allocated, thats ok too. 351 */ 352 353 static int gfs2_allocate_page_backing(struct page *page) 354 { 355 struct inode *inode = page->mapping->host; 356 struct buffer_head bh; 357 unsigned long size = PAGE_CACHE_SIZE; 358 u64 lblock = page->index << (PAGE_CACHE_SHIFT - inode->i_blkbits); 359 360 do { 361 bh.b_state = 0; 362 bh.b_size = size; 363 gfs2_block_map(inode, lblock, &bh, 1); 364 if (!buffer_mapped(&bh)) 365 return -EIO; 366 size -= bh.b_size; 367 lblock += (bh.b_size >> inode->i_blkbits); 368 } while(size > 0); 369 return 0; 370 } 371 372 /** 373 * gfs2_page_mkwrite - Make a shared, mmap()ed, page writable 374 * @vma: The virtual memory area 375 * @vmf: The virtual memory fault containing the page to become writable 376 * 377 * When the page becomes writable, we need to ensure that we have 378 * blocks allocated on disk to back that page. 379 */ 380 381 static int gfs2_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf) 382 { 383 struct page *page = vmf->page; 384 struct inode *inode = file_inode(vma->vm_file); 385 struct gfs2_inode *ip = GFS2_I(inode); 386 struct gfs2_sbd *sdp = GFS2_SB(inode); 387 struct gfs2_alloc_parms ap = { .aflags = 0, }; 388 unsigned long last_index; 389 u64 pos = page->index << PAGE_CACHE_SHIFT; 390 unsigned int data_blocks, ind_blocks, rblocks; 391 struct gfs2_holder gh; 392 loff_t size; 393 int ret; 394 395 sb_start_pagefault(inode->i_sb); 396 397 /* Update file times before taking page lock */ 398 file_update_time(vma->vm_file); 399 400 ret = get_write_access(inode); 401 if (ret) 402 goto out; 403 404 ret = gfs2_rs_alloc(ip); 405 if (ret) 406 goto out_write_access; 407 408 gfs2_size_hint(vma->vm_file, pos, PAGE_CACHE_SIZE); 409 410 gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh); 411 ret = gfs2_glock_nq(&gh); 412 if (ret) 413 goto out_uninit; 414 415 set_bit(GLF_DIRTY, &ip->i_gl->gl_flags); 416 set_bit(GIF_SW_PAGED, &ip->i_flags); 417 418 if (!gfs2_write_alloc_required(ip, pos, PAGE_CACHE_SIZE)) { 419 lock_page(page); 420 if (!PageUptodate(page) || page->mapping != inode->i_mapping) { 421 ret = -EAGAIN; 422 unlock_page(page); 423 } 424 goto out_unlock; 425 } 426 427 ret = gfs2_rindex_update(sdp); 428 if (ret) 429 goto out_unlock; 430 431 gfs2_write_calc_reserv(ip, PAGE_CACHE_SIZE, &data_blocks, &ind_blocks); 432 ap.target = data_blocks + ind_blocks; 433 ret = gfs2_quota_lock_check(ip, &ap); 434 if (ret) 435 goto out_unlock; 436 ret = gfs2_inplace_reserve(ip, &ap); 437 if (ret) 438 goto out_quota_unlock; 439 440 rblocks = RES_DINODE + ind_blocks; 441 if (gfs2_is_jdata(ip)) 442 rblocks += data_blocks ? data_blocks : 1; 443 if (ind_blocks || data_blocks) { 444 rblocks += RES_STATFS + RES_QUOTA; 445 rblocks += gfs2_rg_blocks(ip, data_blocks + ind_blocks); 446 } 447 ret = gfs2_trans_begin(sdp, rblocks, 0); 448 if (ret) 449 goto out_trans_fail; 450 451 lock_page(page); 452 ret = -EINVAL; 453 size = i_size_read(inode); 454 last_index = (size - 1) >> PAGE_CACHE_SHIFT; 455 /* Check page index against inode size */ 456 if (size == 0 || (page->index > last_index)) 457 goto out_trans_end; 458 459 ret = -EAGAIN; 460 /* If truncated, we must retry the operation, we may have raced 461 * with the glock demotion code. 462 */ 463 if (!PageUptodate(page) || page->mapping != inode->i_mapping) 464 goto out_trans_end; 465 466 /* Unstuff, if required, and allocate backing blocks for page */ 467 ret = 0; 468 if (gfs2_is_stuffed(ip)) 469 ret = gfs2_unstuff_dinode(ip, page); 470 if (ret == 0) 471 ret = gfs2_allocate_page_backing(page); 472 473 out_trans_end: 474 if (ret) 475 unlock_page(page); 476 gfs2_trans_end(sdp); 477 out_trans_fail: 478 gfs2_inplace_release(ip); 479 out_quota_unlock: 480 gfs2_quota_unlock(ip); 481 out_unlock: 482 gfs2_glock_dq(&gh); 483 out_uninit: 484 gfs2_holder_uninit(&gh); 485 if (ret == 0) { 486 set_page_dirty(page); 487 wait_for_stable_page(page); 488 } 489 out_write_access: 490 put_write_access(inode); 491 out: 492 sb_end_pagefault(inode->i_sb); 493 return block_page_mkwrite_return(ret); 494 } 495 496 static const struct vm_operations_struct gfs2_vm_ops = { 497 .fault = filemap_fault, 498 .map_pages = filemap_map_pages, 499 .page_mkwrite = gfs2_page_mkwrite, 500 }; 501 502 /** 503 * gfs2_mmap - 504 * @file: The file to map 505 * @vma: The VMA which described the mapping 506 * 507 * There is no need to get a lock here unless we should be updating 508 * atime. We ignore any locking errors since the only consequence is 509 * a missed atime update (which will just be deferred until later). 510 * 511 * Returns: 0 512 */ 513 514 static int gfs2_mmap(struct file *file, struct vm_area_struct *vma) 515 { 516 struct gfs2_inode *ip = GFS2_I(file->f_mapping->host); 517 518 if (!(file->f_flags & O_NOATIME) && 519 !IS_NOATIME(&ip->i_inode)) { 520 struct gfs2_holder i_gh; 521 int error; 522 523 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, 524 &i_gh); 525 if (error) 526 return error; 527 /* grab lock to update inode */ 528 gfs2_glock_dq_uninit(&i_gh); 529 file_accessed(file); 530 } 531 vma->vm_ops = &gfs2_vm_ops; 532 533 return 0; 534 } 535 536 /** 537 * gfs2_open_common - This is common to open and atomic_open 538 * @inode: The inode being opened 539 * @file: The file being opened 540 * 541 * This maybe called under a glock or not depending upon how it has 542 * been called. We must always be called under a glock for regular 543 * files, however. For other file types, it does not matter whether 544 * we hold the glock or not. 545 * 546 * Returns: Error code or 0 for success 547 */ 548 549 int gfs2_open_common(struct inode *inode, struct file *file) 550 { 551 struct gfs2_file *fp; 552 int ret; 553 554 if (S_ISREG(inode->i_mode)) { 555 ret = generic_file_open(inode, file); 556 if (ret) 557 return ret; 558 } 559 560 fp = kzalloc(sizeof(struct gfs2_file), GFP_NOFS); 561 if (!fp) 562 return -ENOMEM; 563 564 mutex_init(&fp->f_fl_mutex); 565 566 gfs2_assert_warn(GFS2_SB(inode), !file->private_data); 567 file->private_data = fp; 568 return 0; 569 } 570 571 /** 572 * gfs2_open - open a file 573 * @inode: the inode to open 574 * @file: the struct file for this opening 575 * 576 * After atomic_open, this function is only used for opening files 577 * which are already cached. We must still get the glock for regular 578 * files to ensure that we have the file size uptodate for the large 579 * file check which is in the common code. That is only an issue for 580 * regular files though. 581 * 582 * Returns: errno 583 */ 584 585 static int gfs2_open(struct inode *inode, struct file *file) 586 { 587 struct gfs2_inode *ip = GFS2_I(inode); 588 struct gfs2_holder i_gh; 589 int error; 590 bool need_unlock = false; 591 592 if (S_ISREG(ip->i_inode.i_mode)) { 593 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, 594 &i_gh); 595 if (error) 596 return error; 597 need_unlock = true; 598 } 599 600 error = gfs2_open_common(inode, file); 601 602 if (need_unlock) 603 gfs2_glock_dq_uninit(&i_gh); 604 605 return error; 606 } 607 608 /** 609 * gfs2_release - called to close a struct file 610 * @inode: the inode the struct file belongs to 611 * @file: the struct file being closed 612 * 613 * Returns: errno 614 */ 615 616 static int gfs2_release(struct inode *inode, struct file *file) 617 { 618 struct gfs2_inode *ip = GFS2_I(inode); 619 620 kfree(file->private_data); 621 file->private_data = NULL; 622 623 if (!(file->f_mode & FMODE_WRITE)) 624 return 0; 625 626 gfs2_rs_delete(ip, &inode->i_writecount); 627 return 0; 628 } 629 630 /** 631 * gfs2_fsync - sync the dirty data for a file (across the cluster) 632 * @file: the file that points to the dentry 633 * @start: the start position in the file to sync 634 * @end: the end position in the file to sync 635 * @datasync: set if we can ignore timestamp changes 636 * 637 * We split the data flushing here so that we don't wait for the data 638 * until after we've also sent the metadata to disk. Note that for 639 * data=ordered, we will write & wait for the data at the log flush 640 * stage anyway, so this is unlikely to make much of a difference 641 * except in the data=writeback case. 642 * 643 * If the fdatawrite fails due to any reason except -EIO, we will 644 * continue the remainder of the fsync, although we'll still report 645 * the error at the end. This is to match filemap_write_and_wait_range() 646 * behaviour. 647 * 648 * Returns: errno 649 */ 650 651 static int gfs2_fsync(struct file *file, loff_t start, loff_t end, 652 int datasync) 653 { 654 struct address_space *mapping = file->f_mapping; 655 struct inode *inode = mapping->host; 656 int sync_state = inode->i_state & I_DIRTY_ALL; 657 struct gfs2_inode *ip = GFS2_I(inode); 658 int ret = 0, ret1 = 0; 659 660 if (mapping->nrpages) { 661 ret1 = filemap_fdatawrite_range(mapping, start, end); 662 if (ret1 == -EIO) 663 return ret1; 664 } 665 666 if (!gfs2_is_jdata(ip)) 667 sync_state &= ~I_DIRTY_PAGES; 668 if (datasync) 669 sync_state &= ~(I_DIRTY_SYNC | I_DIRTY_TIME); 670 671 if (sync_state) { 672 ret = sync_inode_metadata(inode, 1); 673 if (ret) 674 return ret; 675 if (gfs2_is_jdata(ip)) 676 filemap_write_and_wait(mapping); 677 gfs2_ail_flush(ip->i_gl, 1); 678 } 679 680 if (mapping->nrpages) 681 ret = filemap_fdatawait_range(mapping, start, end); 682 683 return ret ? ret : ret1; 684 } 685 686 /** 687 * gfs2_file_write_iter - Perform a write to a file 688 * @iocb: The io context 689 * @iov: The data to write 690 * @nr_segs: Number of @iov segments 691 * @pos: The file position 692 * 693 * We have to do a lock/unlock here to refresh the inode size for 694 * O_APPEND writes, otherwise we can land up writing at the wrong 695 * offset. There is still a race, but provided the app is using its 696 * own file locking, this will make O_APPEND work as expected. 697 * 698 */ 699 700 static ssize_t gfs2_file_write_iter(struct kiocb *iocb, struct iov_iter *from) 701 { 702 struct file *file = iocb->ki_filp; 703 struct gfs2_inode *ip = GFS2_I(file_inode(file)); 704 int ret; 705 706 ret = gfs2_rs_alloc(ip); 707 if (ret) 708 return ret; 709 710 gfs2_size_hint(file, iocb->ki_pos, iov_iter_count(from)); 711 712 if (iocb->ki_flags & IOCB_APPEND) { 713 struct gfs2_holder gh; 714 715 ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &gh); 716 if (ret) 717 return ret; 718 gfs2_glock_dq_uninit(&gh); 719 } 720 721 return generic_file_write_iter(iocb, from); 722 } 723 724 static int fallocate_chunk(struct inode *inode, loff_t offset, loff_t len, 725 int mode) 726 { 727 struct gfs2_inode *ip = GFS2_I(inode); 728 struct buffer_head *dibh; 729 int error; 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 out: 764 brelse(dibh); 765 return error; 766 } 767 /** 768 * calc_max_reserv() - Reverse of write_calc_reserv. Given a number of 769 * blocks, determine how many bytes can be written. 770 * @ip: The inode in question. 771 * @len: Max cap of bytes. What we return in *len must be <= this. 772 * @data_blocks: Compute and return the number of data blocks needed 773 * @ind_blocks: Compute and return the number of indirect blocks needed 774 * @max_blocks: The total blocks available to work with. 775 * 776 * Returns: void, but @len, @data_blocks and @ind_blocks are filled in. 777 */ 778 static void calc_max_reserv(struct gfs2_inode *ip, loff_t *len, 779 unsigned int *data_blocks, unsigned int *ind_blocks, 780 unsigned int max_blocks) 781 { 782 loff_t max = *len; 783 const struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode); 784 unsigned int tmp, max_data = max_blocks - 3 * (sdp->sd_max_height - 1); 785 786 for (tmp = max_data; tmp > sdp->sd_diptrs;) { 787 tmp = DIV_ROUND_UP(tmp, sdp->sd_inptrs); 788 max_data -= tmp; 789 } 790 791 *data_blocks = max_data; 792 *ind_blocks = max_blocks - max_data; 793 *len = ((loff_t)max_data - 3) << sdp->sd_sb.sb_bsize_shift; 794 if (*len > max) { 795 *len = max; 796 gfs2_write_calc_reserv(ip, max, data_blocks, ind_blocks); 797 } 798 } 799 800 static long __gfs2_fallocate(struct file *file, int mode, loff_t offset, loff_t len) 801 { 802 struct inode *inode = file_inode(file); 803 struct gfs2_sbd *sdp = GFS2_SB(inode); 804 struct gfs2_inode *ip = GFS2_I(inode); 805 struct gfs2_alloc_parms ap = { .aflags = 0, }; 806 unsigned int data_blocks = 0, ind_blocks = 0, rblocks; 807 loff_t bytes, max_bytes, max_blks = UINT_MAX; 808 int error; 809 const loff_t pos = offset; 810 const loff_t count = len; 811 loff_t bsize_mask = ~((loff_t)sdp->sd_sb.sb_bsize - 1); 812 loff_t next = (offset + len - 1) >> sdp->sd_sb.sb_bsize_shift; 813 loff_t max_chunk_size = UINT_MAX & bsize_mask; 814 815 next = (next + 1) << sdp->sd_sb.sb_bsize_shift; 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 gfs2_size_hint(file, offset, len); 828 829 gfs2_write_calc_reserv(ip, PAGE_SIZE, &data_blocks, &ind_blocks); 830 ap.min_target = data_blocks + ind_blocks; 831 832 while (len > 0) { 833 if (len < bytes) 834 bytes = len; 835 if (!gfs2_write_alloc_required(ip, offset, bytes)) { 836 len -= bytes; 837 offset += bytes; 838 continue; 839 } 840 841 /* We need to determine how many bytes we can actually 842 * fallocate without exceeding quota or going over the 843 * end of the fs. We start off optimistically by assuming 844 * we can write max_bytes */ 845 max_bytes = (len > max_chunk_size) ? max_chunk_size : len; 846 847 /* Since max_bytes is most likely a theoretical max, we 848 * calculate a more realistic 'bytes' to serve as a good 849 * starting point for the number of bytes we may be able 850 * to write */ 851 gfs2_write_calc_reserv(ip, bytes, &data_blocks, &ind_blocks); 852 ap.target = data_blocks + ind_blocks; 853 854 error = gfs2_quota_lock_check(ip, &ap); 855 if (error) 856 return error; 857 /* ap.allowed tells us how many blocks quota will allow 858 * us to write. Check if this reduces max_blks */ 859 if (ap.allowed && ap.allowed < max_blks) 860 max_blks = ap.allowed; 861 862 error = gfs2_inplace_reserve(ip, &ap); 863 if (error) 864 goto out_qunlock; 865 866 /* check if the selected rgrp limits our max_blks further */ 867 if (ap.allowed && ap.allowed < max_blks) 868 max_blks = ap.allowed; 869 870 /* Almost done. Calculate bytes that can be written using 871 * max_blks. We also recompute max_bytes, data_blocks and 872 * ind_blocks */ 873 calc_max_reserv(ip, &max_bytes, &data_blocks, 874 &ind_blocks, max_blks); 875 876 rblocks = RES_DINODE + ind_blocks + RES_STATFS + RES_QUOTA + 877 RES_RG_HDR + gfs2_rg_blocks(ip, data_blocks + ind_blocks); 878 if (gfs2_is_jdata(ip)) 879 rblocks += data_blocks ? data_blocks : 1; 880 881 error = gfs2_trans_begin(sdp, rblocks, 882 PAGE_CACHE_SIZE/sdp->sd_sb.sb_bsize); 883 if (error) 884 goto out_trans_fail; 885 886 error = fallocate_chunk(inode, offset, max_bytes, mode); 887 gfs2_trans_end(sdp); 888 889 if (error) 890 goto out_trans_fail; 891 892 len -= max_bytes; 893 offset += max_bytes; 894 gfs2_inplace_release(ip); 895 gfs2_quota_unlock(ip); 896 } 897 898 if (!(mode & FALLOC_FL_KEEP_SIZE) && (pos + count) > inode->i_size) { 899 i_size_write(inode, pos + count); 900 /* Marks the inode as dirty */ 901 file_update_time(file); 902 } 903 904 return generic_write_sync(file, pos, count); 905 906 out_trans_fail: 907 gfs2_inplace_release(ip); 908 out_qunlock: 909 gfs2_quota_unlock(ip); 910 return error; 911 } 912 913 static long gfs2_fallocate(struct file *file, int mode, loff_t offset, loff_t len) 914 { 915 struct inode *inode = file_inode(file); 916 struct gfs2_inode *ip = GFS2_I(inode); 917 struct gfs2_holder gh; 918 int ret; 919 920 if ((mode & ~FALLOC_FL_KEEP_SIZE) || gfs2_is_jdata(ip)) 921 return -EOPNOTSUPP; 922 923 mutex_lock(&inode->i_mutex); 924 925 gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh); 926 ret = gfs2_glock_nq(&gh); 927 if (ret) 928 goto out_uninit; 929 930 if (!(mode & FALLOC_FL_KEEP_SIZE) && 931 (offset + len) > inode->i_size) { 932 ret = inode_newsize_ok(inode, offset + len); 933 if (ret) 934 goto out_unlock; 935 } 936 937 ret = get_write_access(inode); 938 if (ret) 939 goto out_unlock; 940 941 ret = gfs2_rs_alloc(ip); 942 if (ret) 943 goto out_putw; 944 945 ret = __gfs2_fallocate(file, mode, offset, len); 946 if (ret) 947 gfs2_rs_deltree(ip->i_res); 948 out_putw: 949 put_write_access(inode); 950 out_unlock: 951 gfs2_glock_dq(&gh); 952 out_uninit: 953 gfs2_holder_uninit(&gh); 954 mutex_unlock(&inode->i_mutex); 955 return ret; 956 } 957 958 static ssize_t gfs2_file_splice_write(struct pipe_inode_info *pipe, 959 struct file *out, loff_t *ppos, 960 size_t len, unsigned int flags) 961 { 962 int error; 963 struct gfs2_inode *ip = GFS2_I(out->f_mapping->host); 964 965 error = gfs2_rs_alloc(ip); 966 if (error) 967 return (ssize_t)error; 968 969 gfs2_size_hint(out, *ppos, len); 970 971 return iter_file_splice_write(pipe, out, ppos, len, flags); 972 } 973 974 #ifdef CONFIG_GFS2_FS_LOCKING_DLM 975 976 /** 977 * gfs2_lock - acquire/release a posix lock on a file 978 * @file: the file pointer 979 * @cmd: either modify or retrieve lock state, possibly wait 980 * @fl: type and range of lock 981 * 982 * Returns: errno 983 */ 984 985 static int gfs2_lock(struct file *file, int cmd, struct file_lock *fl) 986 { 987 struct gfs2_inode *ip = GFS2_I(file->f_mapping->host); 988 struct gfs2_sbd *sdp = GFS2_SB(file->f_mapping->host); 989 struct lm_lockstruct *ls = &sdp->sd_lockstruct; 990 991 if (!(fl->fl_flags & FL_POSIX)) 992 return -ENOLCK; 993 if (__mandatory_lock(&ip->i_inode) && fl->fl_type != F_UNLCK) 994 return -ENOLCK; 995 996 if (cmd == F_CANCELLK) { 997 /* Hack: */ 998 cmd = F_SETLK; 999 fl->fl_type = F_UNLCK; 1000 } 1001 if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags))) { 1002 if (fl->fl_type == F_UNLCK) 1003 posix_lock_file_wait(file, fl); 1004 return -EIO; 1005 } 1006 if (IS_GETLK(cmd)) 1007 return dlm_posix_get(ls->ls_dlm, ip->i_no_addr, file, fl); 1008 else if (fl->fl_type == F_UNLCK) 1009 return dlm_posix_unlock(ls->ls_dlm, ip->i_no_addr, file, fl); 1010 else 1011 return dlm_posix_lock(ls->ls_dlm, ip->i_no_addr, file, cmd, fl); 1012 } 1013 1014 static int do_flock(struct file *file, int cmd, struct file_lock *fl) 1015 { 1016 struct gfs2_file *fp = file->private_data; 1017 struct gfs2_holder *fl_gh = &fp->f_fl_gh; 1018 struct gfs2_inode *ip = GFS2_I(file_inode(file)); 1019 struct gfs2_glock *gl; 1020 unsigned int state; 1021 int flags; 1022 int error = 0; 1023 int sleeptime; 1024 1025 state = (fl->fl_type == F_WRLCK) ? LM_ST_EXCLUSIVE : LM_ST_SHARED; 1026 flags = (IS_SETLKW(cmd) ? 0 : LM_FLAG_TRY_1CB) | GL_EXACT; 1027 1028 mutex_lock(&fp->f_fl_mutex); 1029 1030 gl = fl_gh->gh_gl; 1031 if (gl) { 1032 if (fl_gh->gh_state == state) 1033 goto out; 1034 flock_lock_file_wait(file, 1035 &(struct file_lock){.fl_type = F_UNLCK}); 1036 gfs2_glock_dq(fl_gh); 1037 gfs2_holder_reinit(state, flags, fl_gh); 1038 } else { 1039 error = gfs2_glock_get(GFS2_SB(&ip->i_inode), ip->i_no_addr, 1040 &gfs2_flock_glops, CREATE, &gl); 1041 if (error) 1042 goto out; 1043 gfs2_holder_init(gl, state, flags, fl_gh); 1044 gfs2_glock_put(gl); 1045 } 1046 for (sleeptime = 1; sleeptime <= 4; sleeptime <<= 1) { 1047 error = gfs2_glock_nq(fl_gh); 1048 if (error != GLR_TRYFAILED) 1049 break; 1050 fl_gh->gh_flags = LM_FLAG_TRY | GL_EXACT; 1051 fl_gh->gh_error = 0; 1052 msleep(sleeptime); 1053 } 1054 if (error) { 1055 gfs2_holder_uninit(fl_gh); 1056 if (error == GLR_TRYFAILED) 1057 error = -EAGAIN; 1058 } else { 1059 error = flock_lock_file_wait(file, fl); 1060 gfs2_assert_warn(GFS2_SB(&ip->i_inode), !error); 1061 } 1062 1063 out: 1064 mutex_unlock(&fp->f_fl_mutex); 1065 return error; 1066 } 1067 1068 static void do_unflock(struct file *file, struct file_lock *fl) 1069 { 1070 struct gfs2_file *fp = file->private_data; 1071 struct gfs2_holder *fl_gh = &fp->f_fl_gh; 1072 1073 mutex_lock(&fp->f_fl_mutex); 1074 flock_lock_file_wait(file, fl); 1075 if (fl_gh->gh_gl) { 1076 gfs2_glock_dq(fl_gh); 1077 gfs2_holder_uninit(fl_gh); 1078 } 1079 mutex_unlock(&fp->f_fl_mutex); 1080 } 1081 1082 /** 1083 * gfs2_flock - acquire/release a flock lock on a file 1084 * @file: the file pointer 1085 * @cmd: either modify or retrieve lock state, possibly wait 1086 * @fl: type and range of lock 1087 * 1088 * Returns: errno 1089 */ 1090 1091 static int gfs2_flock(struct file *file, int cmd, struct file_lock *fl) 1092 { 1093 if (!(fl->fl_flags & FL_FLOCK)) 1094 return -ENOLCK; 1095 if (fl->fl_type & LOCK_MAND) 1096 return -EOPNOTSUPP; 1097 1098 if (fl->fl_type == F_UNLCK) { 1099 do_unflock(file, fl); 1100 return 0; 1101 } else { 1102 return do_flock(file, cmd, fl); 1103 } 1104 } 1105 1106 const struct file_operations gfs2_file_fops = { 1107 .llseek = gfs2_llseek, 1108 .read_iter = generic_file_read_iter, 1109 .write_iter = gfs2_file_write_iter, 1110 .unlocked_ioctl = gfs2_ioctl, 1111 .mmap = gfs2_mmap, 1112 .open = gfs2_open, 1113 .release = gfs2_release, 1114 .fsync = gfs2_fsync, 1115 .lock = gfs2_lock, 1116 .flock = gfs2_flock, 1117 .splice_read = generic_file_splice_read, 1118 .splice_write = gfs2_file_splice_write, 1119 .setlease = simple_nosetlease, 1120 .fallocate = gfs2_fallocate, 1121 }; 1122 1123 const struct file_operations gfs2_dir_fops = { 1124 .iterate = gfs2_readdir, 1125 .unlocked_ioctl = gfs2_ioctl, 1126 .open = gfs2_open, 1127 .release = gfs2_release, 1128 .fsync = gfs2_fsync, 1129 .lock = gfs2_lock, 1130 .flock = gfs2_flock, 1131 .llseek = default_llseek, 1132 }; 1133 1134 #endif /* CONFIG_GFS2_FS_LOCKING_DLM */ 1135 1136 const struct file_operations gfs2_file_fops_nolock = { 1137 .llseek = gfs2_llseek, 1138 .read_iter = generic_file_read_iter, 1139 .write_iter = gfs2_file_write_iter, 1140 .unlocked_ioctl = gfs2_ioctl, 1141 .mmap = gfs2_mmap, 1142 .open = gfs2_open, 1143 .release = gfs2_release, 1144 .fsync = gfs2_fsync, 1145 .splice_read = generic_file_splice_read, 1146 .splice_write = gfs2_file_splice_write, 1147 .setlease = generic_setlease, 1148 .fallocate = gfs2_fallocate, 1149 }; 1150 1151 const struct file_operations gfs2_dir_fops_nolock = { 1152 .iterate = gfs2_readdir, 1153 .unlocked_ioctl = gfs2_ioctl, 1154 .open = gfs2_open, 1155 .release = gfs2_release, 1156 .fsync = gfs2_fsync, 1157 .llseek = default_llseek, 1158 }; 1159 1160