| 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 | goto out_uninit; |
| 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 | out_uninit: |
| 173 | gfs2_holder_uninit(&gh); |
| 174 | return error; |
| 175 | } |
| 176 | |
| 177 | void gfs2_set_inode_flags(struct inode *inode) |
| 178 | { |
| 179 | struct gfs2_inode *ip = GFS2_I(inode); |
| 180 | unsigned int flags = inode->i_flags; |
| 181 | |
| 182 | flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC|S_NOSEC); |
| 183 | if ((ip->i_eattr == 0) && !is_sxid(inode->i_mode)) |
| 184 | flags |= S_NOSEC; |
| 185 | if (ip->i_diskflags & GFS2_DIF_IMMUTABLE) |
| 186 | flags |= S_IMMUTABLE; |
| 187 | if (ip->i_diskflags & GFS2_DIF_APPENDONLY) |
| 188 | flags |= S_APPEND; |
| 189 | if (ip->i_diskflags & GFS2_DIF_NOATIME) |
| 190 | flags |= S_NOATIME; |
| 191 | if (ip->i_diskflags & GFS2_DIF_SYNC) |
| 192 | flags |= S_SYNC; |
| 193 | inode->i_flags = flags; |
| 194 | } |
| 195 | |
| 196 | /* Flags that can be set by user space */ |
| 197 | #define GFS2_FLAGS_USER_SET (GFS2_DIF_JDATA| \ |
| 198 | GFS2_DIF_IMMUTABLE| \ |
| 199 | GFS2_DIF_APPENDONLY| \ |
| 200 | GFS2_DIF_NOATIME| \ |
| 201 | GFS2_DIF_SYNC| \ |
| 202 | GFS2_DIF_SYSTEM| \ |
| 203 | GFS2_DIF_TOPDIR| \ |
| 204 | GFS2_DIF_INHERIT_JDATA) |
| 205 | |
| 206 | /** |
| 207 | * do_gfs2_set_flags - set flags on an inode |
| 208 | * @filp: file pointer |
| 209 | * @reqflags: The flags to set |
| 210 | * @mask: Indicates which flags are valid |
| 211 | * |
| 212 | */ |
| 213 | static int do_gfs2_set_flags(struct file *filp, u32 reqflags, u32 mask) |
| 214 | { |
| 215 | struct inode *inode = file_inode(filp); |
| 216 | struct gfs2_inode *ip = GFS2_I(inode); |
| 217 | struct gfs2_sbd *sdp = GFS2_SB(inode); |
| 218 | struct buffer_head *bh; |
| 219 | struct gfs2_holder gh; |
| 220 | int error; |
| 221 | u32 new_flags, flags; |
| 222 | |
| 223 | error = mnt_want_write_file(filp); |
| 224 | if (error) |
| 225 | return error; |
| 226 | |
| 227 | error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh); |
| 228 | if (error) |
| 229 | goto out_drop_write; |
| 230 | |
| 231 | error = -EACCES; |
| 232 | if (!inode_owner_or_capable(inode)) |
| 233 | goto out; |
| 234 | |
| 235 | error = 0; |
| 236 | flags = ip->i_diskflags; |
| 237 | new_flags = (flags & ~mask) | (reqflags & mask); |
| 238 | if ((new_flags ^ flags) == 0) |
| 239 | goto out; |
| 240 | |
| 241 | error = -EINVAL; |
| 242 | if ((new_flags ^ flags) & ~GFS2_FLAGS_USER_SET) |
| 243 | goto out; |
| 244 | |
| 245 | error = -EPERM; |
| 246 | if (IS_IMMUTABLE(inode) && (new_flags & GFS2_DIF_IMMUTABLE)) |
| 247 | goto out; |
| 248 | if (IS_APPEND(inode) && (new_flags & GFS2_DIF_APPENDONLY)) |
| 249 | goto out; |
| 250 | if (((new_flags ^ flags) & GFS2_DIF_IMMUTABLE) && |
| 251 | !capable(CAP_LINUX_IMMUTABLE)) |
| 252 | goto out; |
| 253 | if (!IS_IMMUTABLE(inode)) { |
| 254 | error = gfs2_permission(inode, MAY_WRITE); |
| 255 | if (error) |
| 256 | goto out; |
| 257 | } |
| 258 | if ((flags ^ new_flags) & GFS2_DIF_JDATA) { |
| 259 | if (flags & GFS2_DIF_JDATA) |
| 260 | gfs2_log_flush(sdp, ip->i_gl, NORMAL_FLUSH); |
| 261 | error = filemap_fdatawrite(inode->i_mapping); |
| 262 | if (error) |
| 263 | goto out; |
| 264 | error = filemap_fdatawait(inode->i_mapping); |
| 265 | if (error) |
| 266 | goto out; |
| 267 | } |
| 268 | error = gfs2_trans_begin(sdp, RES_DINODE, 0); |
| 269 | if (error) |
| 270 | goto out; |
| 271 | error = gfs2_meta_inode_buffer(ip, &bh); |
| 272 | if (error) |
| 273 | goto out_trans_end; |
| 274 | gfs2_trans_add_meta(ip->i_gl, bh); |
| 275 | ip->i_diskflags = new_flags; |
| 276 | gfs2_dinode_out(ip, bh->b_data); |
| 277 | brelse(bh); |
| 278 | gfs2_set_inode_flags(inode); |
| 279 | gfs2_set_aops(inode); |
| 280 | out_trans_end: |
| 281 | gfs2_trans_end(sdp); |
| 282 | out: |
| 283 | gfs2_glock_dq_uninit(&gh); |
| 284 | out_drop_write: |
| 285 | mnt_drop_write_file(filp); |
| 286 | return error; |
| 287 | } |
| 288 | |
| 289 | static int gfs2_set_flags(struct file *filp, u32 __user *ptr) |
| 290 | { |
| 291 | struct inode *inode = file_inode(filp); |
| 292 | u32 fsflags, gfsflags; |
| 293 | |
| 294 | if (get_user(fsflags, ptr)) |
| 295 | return -EFAULT; |
| 296 | |
| 297 | gfsflags = fsflags_cvt(fsflags_to_gfs2, fsflags); |
| 298 | if (!S_ISDIR(inode->i_mode)) { |
| 299 | gfsflags &= ~GFS2_DIF_TOPDIR; |
| 300 | if (gfsflags & GFS2_DIF_INHERIT_JDATA) |
| 301 | gfsflags ^= (GFS2_DIF_JDATA | GFS2_DIF_INHERIT_JDATA); |
| 302 | return do_gfs2_set_flags(filp, gfsflags, ~GFS2_DIF_SYSTEM); |
| 303 | } |
| 304 | return do_gfs2_set_flags(filp, gfsflags, ~(GFS2_DIF_SYSTEM | GFS2_DIF_JDATA)); |
| 305 | } |
| 306 | |
| 307 | static long gfs2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) |
| 308 | { |
| 309 | switch(cmd) { |
| 310 | case FS_IOC_GETFLAGS: |
| 311 | return gfs2_get_flags(filp, (u32 __user *)arg); |
| 312 | case FS_IOC_SETFLAGS: |
| 313 | return gfs2_set_flags(filp, (u32 __user *)arg); |
| 314 | case FITRIM: |
| 315 | return gfs2_fitrim(filp, (void __user *)arg); |
| 316 | } |
| 317 | return -ENOTTY; |
| 318 | } |
| 319 | |
| 320 | /** |
| 321 | * gfs2_size_hint - Give a hint to the size of a write request |
| 322 | * @filep: The struct file |
| 323 | * @offset: The file offset of the write |
| 324 | * @size: The length of the write |
| 325 | * |
| 326 | * When we are about to do a write, this function records the total |
| 327 | * write size in order to provide a suitable hint to the lower layers |
| 328 | * about how many blocks will be required. |
| 329 | * |
| 330 | */ |
| 331 | |
| 332 | static void gfs2_size_hint(struct file *filep, loff_t offset, size_t size) |
| 333 | { |
| 334 | struct inode *inode = file_inode(filep); |
| 335 | struct gfs2_sbd *sdp = GFS2_SB(inode); |
| 336 | struct gfs2_inode *ip = GFS2_I(inode); |
| 337 | size_t blks = (size + sdp->sd_sb.sb_bsize - 1) >> sdp->sd_sb.sb_bsize_shift; |
| 338 | int hint = min_t(size_t, INT_MAX, blks); |
| 339 | |
| 340 | if (hint > atomic_read(&ip->i_res.rs_sizehint)) |
| 341 | atomic_set(&ip->i_res.rs_sizehint, hint); |
| 342 | } |
| 343 | |
| 344 | /** |
| 345 | * gfs2_allocate_page_backing - Use bmap to allocate blocks |
| 346 | * @page: The (locked) page to allocate backing for |
| 347 | * |
| 348 | * We try to allocate all the blocks required for the page in |
| 349 | * one go. This might fail for various reasons, so we keep |
| 350 | * trying until all the blocks to back this page are allocated. |
| 351 | * If some of the blocks are already allocated, thats ok too. |
| 352 | */ |
| 353 | |
| 354 | static int gfs2_allocate_page_backing(struct page *page) |
| 355 | { |
| 356 | struct inode *inode = page->mapping->host; |
| 357 | struct buffer_head bh; |
| 358 | unsigned long size = PAGE_SIZE; |
| 359 | u64 lblock = page->index << (PAGE_SHIFT - inode->i_blkbits); |
| 360 | |
| 361 | do { |
| 362 | bh.b_state = 0; |
| 363 | bh.b_size = size; |
| 364 | gfs2_block_map(inode, lblock, &bh, 1); |
| 365 | if (!buffer_mapped(&bh)) |
| 366 | return -EIO; |
| 367 | size -= bh.b_size; |
| 368 | lblock += (bh.b_size >> inode->i_blkbits); |
| 369 | } while(size > 0); |
| 370 | return 0; |
| 371 | } |
| 372 | |
| 373 | /** |
| 374 | * gfs2_page_mkwrite - Make a shared, mmap()ed, page writable |
| 375 | * @vma: The virtual memory area |
| 376 | * @vmf: The virtual memory fault containing the page to become writable |
| 377 | * |
| 378 | * When the page becomes writable, we need to ensure that we have |
| 379 | * blocks allocated on disk to back that page. |
| 380 | */ |
| 381 | |
| 382 | static int gfs2_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf) |
| 383 | { |
| 384 | struct page *page = vmf->page; |
| 385 | struct inode *inode = file_inode(vma->vm_file); |
| 386 | struct gfs2_inode *ip = GFS2_I(inode); |
| 387 | struct gfs2_sbd *sdp = GFS2_SB(inode); |
| 388 | struct gfs2_alloc_parms ap = { .aflags = 0, }; |
| 389 | unsigned long last_index; |
| 390 | u64 pos = page->index << PAGE_SHIFT; |
| 391 | unsigned int data_blocks, ind_blocks, rblocks; |
| 392 | struct gfs2_holder gh; |
| 393 | loff_t size; |
| 394 | int ret; |
| 395 | |
| 396 | sb_start_pagefault(inode->i_sb); |
| 397 | |
| 398 | /* Update file times before taking page lock */ |
| 399 | file_update_time(vma->vm_file); |
| 400 | |
| 401 | ret = gfs2_rsqa_alloc(ip); |
| 402 | if (ret) |
| 403 | goto out; |
| 404 | |
| 405 | gfs2_size_hint(vma->vm_file, pos, PAGE_SIZE); |
| 406 | |
| 407 | gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh); |
| 408 | ret = gfs2_glock_nq(&gh); |
| 409 | if (ret) |
| 410 | goto out_uninit; |
| 411 | |
| 412 | set_bit(GLF_DIRTY, &ip->i_gl->gl_flags); |
| 413 | set_bit(GIF_SW_PAGED, &ip->i_flags); |
| 414 | |
| 415 | if (!gfs2_write_alloc_required(ip, pos, PAGE_SIZE)) { |
| 416 | lock_page(page); |
| 417 | if (!PageUptodate(page) || page->mapping != inode->i_mapping) { |
| 418 | ret = -EAGAIN; |
| 419 | unlock_page(page); |
| 420 | } |
| 421 | goto out_unlock; |
| 422 | } |
| 423 | |
| 424 | ret = gfs2_rindex_update(sdp); |
| 425 | if (ret) |
| 426 | goto out_unlock; |
| 427 | |
| 428 | gfs2_write_calc_reserv(ip, PAGE_SIZE, &data_blocks, &ind_blocks); |
| 429 | ap.target = data_blocks + ind_blocks; |
| 430 | ret = gfs2_quota_lock_check(ip, &ap); |
| 431 | if (ret) |
| 432 | goto out_unlock; |
| 433 | ret = gfs2_inplace_reserve(ip, &ap); |
| 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_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: |
| 487 | sb_end_pagefault(inode->i_sb); |
| 488 | return block_page_mkwrite_return(ret); |
| 489 | } |
| 490 | |
| 491 | static const struct vm_operations_struct gfs2_vm_ops = { |
| 492 | .fault = filemap_fault, |
| 493 | .map_pages = filemap_map_pages, |
| 494 | .page_mkwrite = gfs2_page_mkwrite, |
| 495 | }; |
| 496 | |
| 497 | /** |
| 498 | * gfs2_mmap - |
| 499 | * @file: The file to map |
| 500 | * @vma: The VMA which described the mapping |
| 501 | * |
| 502 | * There is no need to get a lock here unless we should be updating |
| 503 | * atime. We ignore any locking errors since the only consequence is |
| 504 | * a missed atime update (which will just be deferred until later). |
| 505 | * |
| 506 | * Returns: 0 |
| 507 | */ |
| 508 | |
| 509 | static int gfs2_mmap(struct file *file, struct vm_area_struct *vma) |
| 510 | { |
| 511 | struct gfs2_inode *ip = GFS2_I(file->f_mapping->host); |
| 512 | |
| 513 | if (!(file->f_flags & O_NOATIME) && |
| 514 | !IS_NOATIME(&ip->i_inode)) { |
| 515 | struct gfs2_holder i_gh; |
| 516 | int error; |
| 517 | |
| 518 | error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, |
| 519 | &i_gh); |
| 520 | if (error) |
| 521 | return error; |
| 522 | /* grab lock to update inode */ |
| 523 | gfs2_glock_dq_uninit(&i_gh); |
| 524 | file_accessed(file); |
| 525 | } |
| 526 | vma->vm_ops = &gfs2_vm_ops; |
| 527 | |
| 528 | return 0; |
| 529 | } |
| 530 | |
| 531 | /** |
| 532 | * gfs2_open_common - This is common to open and atomic_open |
| 533 | * @inode: The inode being opened |
| 534 | * @file: The file being opened |
| 535 | * |
| 536 | * This maybe called under a glock or not depending upon how it has |
| 537 | * been called. We must always be called under a glock for regular |
| 538 | * files, however. For other file types, it does not matter whether |
| 539 | * we hold the glock or not. |
| 540 | * |
| 541 | * Returns: Error code or 0 for success |
| 542 | */ |
| 543 | |
| 544 | int gfs2_open_common(struct inode *inode, struct file *file) |
| 545 | { |
| 546 | struct gfs2_file *fp; |
| 547 | int ret; |
| 548 | |
| 549 | if (S_ISREG(inode->i_mode)) { |
| 550 | ret = generic_file_open(inode, file); |
| 551 | if (ret) |
| 552 | return ret; |
| 553 | } |
| 554 | |
| 555 | fp = kzalloc(sizeof(struct gfs2_file), GFP_NOFS); |
| 556 | if (!fp) |
| 557 | return -ENOMEM; |
| 558 | |
| 559 | mutex_init(&fp->f_fl_mutex); |
| 560 | |
| 561 | gfs2_assert_warn(GFS2_SB(inode), !file->private_data); |
| 562 | file->private_data = fp; |
| 563 | return 0; |
| 564 | } |
| 565 | |
| 566 | /** |
| 567 | * gfs2_open - open a file |
| 568 | * @inode: the inode to open |
| 569 | * @file: the struct file for this opening |
| 570 | * |
| 571 | * After atomic_open, this function is only used for opening files |
| 572 | * which are already cached. We must still get the glock for regular |
| 573 | * files to ensure that we have the file size uptodate for the large |
| 574 | * file check which is in the common code. That is only an issue for |
| 575 | * regular files though. |
| 576 | * |
| 577 | * Returns: errno |
| 578 | */ |
| 579 | |
| 580 | static int gfs2_open(struct inode *inode, struct file *file) |
| 581 | { |
| 582 | struct gfs2_inode *ip = GFS2_I(inode); |
| 583 | struct gfs2_holder i_gh; |
| 584 | int error; |
| 585 | bool need_unlock = false; |
| 586 | |
| 587 | if (S_ISREG(ip->i_inode.i_mode)) { |
| 588 | error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, |
| 589 | &i_gh); |
| 590 | if (error) |
| 591 | return error; |
| 592 | need_unlock = true; |
| 593 | } |
| 594 | |
| 595 | error = gfs2_open_common(inode, file); |
| 596 | |
| 597 | if (need_unlock) |
| 598 | gfs2_glock_dq_uninit(&i_gh); |
| 599 | |
| 600 | return error; |
| 601 | } |
| 602 | |
| 603 | /** |
| 604 | * gfs2_release - called to close a struct file |
| 605 | * @inode: the inode the struct file belongs to |
| 606 | * @file: the struct file being closed |
| 607 | * |
| 608 | * Returns: errno |
| 609 | */ |
| 610 | |
| 611 | static int gfs2_release(struct inode *inode, struct file *file) |
| 612 | { |
| 613 | struct gfs2_inode *ip = GFS2_I(inode); |
| 614 | |
| 615 | kfree(file->private_data); |
| 616 | file->private_data = NULL; |
| 617 | |
| 618 | if (!(file->f_mode & FMODE_WRITE)) |
| 619 | return 0; |
| 620 | |
| 621 | gfs2_rsqa_delete(ip, &inode->i_writecount); |
| 622 | return 0; |
| 623 | } |
| 624 | |
| 625 | /** |
| 626 | * gfs2_fsync - sync the dirty data for a file (across the cluster) |
| 627 | * @file: the file that points to the dentry |
| 628 | * @start: the start position in the file to sync |
| 629 | * @end: the end position in the file to sync |
| 630 | * @datasync: set if we can ignore timestamp changes |
| 631 | * |
| 632 | * We split the data flushing here so that we don't wait for the data |
| 633 | * until after we've also sent the metadata to disk. Note that for |
| 634 | * data=ordered, we will write & wait for the data at the log flush |
| 635 | * stage anyway, so this is unlikely to make much of a difference |
| 636 | * except in the data=writeback case. |
| 637 | * |
| 638 | * If the fdatawrite fails due to any reason except -EIO, we will |
| 639 | * continue the remainder of the fsync, although we'll still report |
| 640 | * the error at the end. This is to match filemap_write_and_wait_range() |
| 641 | * behaviour. |
| 642 | * |
| 643 | * Returns: errno |
| 644 | */ |
| 645 | |
| 646 | static int gfs2_fsync(struct file *file, loff_t start, loff_t end, |
| 647 | int datasync) |
| 648 | { |
| 649 | struct address_space *mapping = file->f_mapping; |
| 650 | struct inode *inode = mapping->host; |
| 651 | int sync_state = inode->i_state & I_DIRTY_ALL; |
| 652 | struct gfs2_inode *ip = GFS2_I(inode); |
| 653 | int ret = 0, ret1 = 0; |
| 654 | |
| 655 | if (mapping->nrpages) { |
| 656 | ret1 = filemap_fdatawrite_range(mapping, start, end); |
| 657 | if (ret1 == -EIO) |
| 658 | return ret1; |
| 659 | } |
| 660 | |
| 661 | if (!gfs2_is_jdata(ip)) |
| 662 | sync_state &= ~I_DIRTY_PAGES; |
| 663 | if (datasync) |
| 664 | sync_state &= ~(I_DIRTY_SYNC | I_DIRTY_TIME); |
| 665 | |
| 666 | if (sync_state) { |
| 667 | ret = sync_inode_metadata(inode, 1); |
| 668 | if (ret) |
| 669 | return ret; |
| 670 | if (gfs2_is_jdata(ip)) |
| 671 | filemap_write_and_wait(mapping); |
| 672 | gfs2_ail_flush(ip->i_gl, 1); |
| 673 | } |
| 674 | |
| 675 | if (mapping->nrpages) |
| 676 | ret = filemap_fdatawait_range(mapping, start, end); |
| 677 | |
| 678 | return ret ? ret : ret1; |
| 679 | } |
| 680 | |
| 681 | /** |
| 682 | * gfs2_file_write_iter - Perform a write to a file |
| 683 | * @iocb: The io context |
| 684 | * @iov: The data to write |
| 685 | * @nr_segs: Number of @iov segments |
| 686 | * @pos: The file position |
| 687 | * |
| 688 | * We have to do a lock/unlock here to refresh the inode size for |
| 689 | * O_APPEND writes, otherwise we can land up writing at the wrong |
| 690 | * offset. There is still a race, but provided the app is using its |
| 691 | * own file locking, this will make O_APPEND work as expected. |
| 692 | * |
| 693 | */ |
| 694 | |
| 695 | static ssize_t gfs2_file_write_iter(struct kiocb *iocb, struct iov_iter *from) |
| 696 | { |
| 697 | struct file *file = iocb->ki_filp; |
| 698 | struct gfs2_inode *ip = GFS2_I(file_inode(file)); |
| 699 | int ret; |
| 700 | |
| 701 | ret = gfs2_rsqa_alloc(ip); |
| 702 | if (ret) |
| 703 | return ret; |
| 704 | |
| 705 | gfs2_size_hint(file, iocb->ki_pos, iov_iter_count(from)); |
| 706 | |
| 707 | if (iocb->ki_flags & IOCB_APPEND) { |
| 708 | struct gfs2_holder gh; |
| 709 | |
| 710 | ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &gh); |
| 711 | if (ret) |
| 712 | return ret; |
| 713 | gfs2_glock_dq_uninit(&gh); |
| 714 | } |
| 715 | |
| 716 | return generic_file_write_iter(iocb, from); |
| 717 | } |
| 718 | |
| 719 | static int fallocate_chunk(struct inode *inode, loff_t offset, loff_t len, |
| 720 | int mode) |
| 721 | { |
| 722 | struct gfs2_inode *ip = GFS2_I(inode); |
| 723 | struct buffer_head *dibh; |
| 724 | int error; |
| 725 | unsigned int nr_blks; |
| 726 | sector_t lblock = offset >> inode->i_blkbits; |
| 727 | |
| 728 | error = gfs2_meta_inode_buffer(ip, &dibh); |
| 729 | if (unlikely(error)) |
| 730 | return error; |
| 731 | |
| 732 | gfs2_trans_add_meta(ip->i_gl, dibh); |
| 733 | |
| 734 | if (gfs2_is_stuffed(ip)) { |
| 735 | error = gfs2_unstuff_dinode(ip, NULL); |
| 736 | if (unlikely(error)) |
| 737 | goto out; |
| 738 | } |
| 739 | |
| 740 | while (len) { |
| 741 | struct buffer_head bh_map = { .b_state = 0, .b_blocknr = 0 }; |
| 742 | bh_map.b_size = len; |
| 743 | set_buffer_zeronew(&bh_map); |
| 744 | |
| 745 | error = gfs2_block_map(inode, lblock, &bh_map, 1); |
| 746 | if (unlikely(error)) |
| 747 | goto out; |
| 748 | len -= bh_map.b_size; |
| 749 | nr_blks = bh_map.b_size >> inode->i_blkbits; |
| 750 | lblock += nr_blks; |
| 751 | if (!buffer_new(&bh_map)) |
| 752 | continue; |
| 753 | if (unlikely(!buffer_zeronew(&bh_map))) { |
| 754 | error = -EIO; |
| 755 | goto out; |
| 756 | } |
| 757 | } |
| 758 | out: |
| 759 | brelse(dibh); |
| 760 | return error; |
| 761 | } |
| 762 | /** |
| 763 | * calc_max_reserv() - Reverse of write_calc_reserv. Given a number of |
| 764 | * blocks, determine how many bytes can be written. |
| 765 | * @ip: The inode in question. |
| 766 | * @len: Max cap of bytes. What we return in *len must be <= this. |
| 767 | * @data_blocks: Compute and return the number of data blocks needed |
| 768 | * @ind_blocks: Compute and return the number of indirect blocks needed |
| 769 | * @max_blocks: The total blocks available to work with. |
| 770 | * |
| 771 | * Returns: void, but @len, @data_blocks and @ind_blocks are filled in. |
| 772 | */ |
| 773 | static void calc_max_reserv(struct gfs2_inode *ip, loff_t *len, |
| 774 | unsigned int *data_blocks, unsigned int *ind_blocks, |
| 775 | unsigned int max_blocks) |
| 776 | { |
| 777 | loff_t max = *len; |
| 778 | const struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode); |
| 779 | unsigned int tmp, max_data = max_blocks - 3 * (sdp->sd_max_height - 1); |
| 780 | |
| 781 | for (tmp = max_data; tmp > sdp->sd_diptrs;) { |
| 782 | tmp = DIV_ROUND_UP(tmp, sdp->sd_inptrs); |
| 783 | max_data -= tmp; |
| 784 | } |
| 785 | |
| 786 | *data_blocks = max_data; |
| 787 | *ind_blocks = max_blocks - max_data; |
| 788 | *len = ((loff_t)max_data - 3) << sdp->sd_sb.sb_bsize_shift; |
| 789 | if (*len > max) { |
| 790 | *len = max; |
| 791 | gfs2_write_calc_reserv(ip, max, data_blocks, ind_blocks); |
| 792 | } |
| 793 | } |
| 794 | |
| 795 | static long __gfs2_fallocate(struct file *file, int mode, loff_t offset, loff_t len) |
| 796 | { |
| 797 | struct inode *inode = file_inode(file); |
| 798 | struct gfs2_sbd *sdp = GFS2_SB(inode); |
| 799 | struct gfs2_inode *ip = GFS2_I(inode); |
| 800 | struct gfs2_alloc_parms ap = { .aflags = 0, }; |
| 801 | unsigned int data_blocks = 0, ind_blocks = 0, rblocks; |
| 802 | loff_t bytes, max_bytes, max_blks = UINT_MAX; |
| 803 | int error; |
| 804 | const loff_t pos = offset; |
| 805 | const loff_t count = len; |
| 806 | loff_t bsize_mask = ~((loff_t)sdp->sd_sb.sb_bsize - 1); |
| 807 | loff_t next = (offset + len - 1) >> sdp->sd_sb.sb_bsize_shift; |
| 808 | loff_t max_chunk_size = UINT_MAX & bsize_mask; |
| 809 | |
| 810 | next = (next + 1) << sdp->sd_sb.sb_bsize_shift; |
| 811 | |
| 812 | offset &= bsize_mask; |
| 813 | |
| 814 | len = next - offset; |
| 815 | bytes = sdp->sd_max_rg_data * sdp->sd_sb.sb_bsize / 2; |
| 816 | if (!bytes) |
| 817 | bytes = UINT_MAX; |
| 818 | bytes &= bsize_mask; |
| 819 | if (bytes == 0) |
| 820 | bytes = sdp->sd_sb.sb_bsize; |
| 821 | |
| 822 | gfs2_size_hint(file, offset, len); |
| 823 | |
| 824 | gfs2_write_calc_reserv(ip, PAGE_SIZE, &data_blocks, &ind_blocks); |
| 825 | ap.min_target = data_blocks + ind_blocks; |
| 826 | |
| 827 | while (len > 0) { |
| 828 | if (len < bytes) |
| 829 | bytes = len; |
| 830 | if (!gfs2_write_alloc_required(ip, offset, bytes)) { |
| 831 | len -= bytes; |
| 832 | offset += bytes; |
| 833 | continue; |
| 834 | } |
| 835 | |
| 836 | /* We need to determine how many bytes we can actually |
| 837 | * fallocate without exceeding quota or going over the |
| 838 | * end of the fs. We start off optimistically by assuming |
| 839 | * we can write max_bytes */ |
| 840 | max_bytes = (len > max_chunk_size) ? max_chunk_size : len; |
| 841 | |
| 842 | /* Since max_bytes is most likely a theoretical max, we |
| 843 | * calculate a more realistic 'bytes' to serve as a good |
| 844 | * starting point for the number of bytes we may be able |
| 845 | * to write */ |
| 846 | gfs2_write_calc_reserv(ip, bytes, &data_blocks, &ind_blocks); |
| 847 | ap.target = data_blocks + ind_blocks; |
| 848 | |
| 849 | error = gfs2_quota_lock_check(ip, &ap); |
| 850 | if (error) |
| 851 | return error; |
| 852 | /* ap.allowed tells us how many blocks quota will allow |
| 853 | * us to write. Check if this reduces max_blks */ |
| 854 | if (ap.allowed && ap.allowed < max_blks) |
| 855 | max_blks = ap.allowed; |
| 856 | |
| 857 | error = gfs2_inplace_reserve(ip, &ap); |
| 858 | if (error) |
| 859 | goto out_qunlock; |
| 860 | |
| 861 | /* check if the selected rgrp limits our max_blks further */ |
| 862 | if (ap.allowed && ap.allowed < max_blks) |
| 863 | max_blks = ap.allowed; |
| 864 | |
| 865 | /* Almost done. Calculate bytes that can be written using |
| 866 | * max_blks. We also recompute max_bytes, data_blocks and |
| 867 | * ind_blocks */ |
| 868 | calc_max_reserv(ip, &max_bytes, &data_blocks, |
| 869 | &ind_blocks, max_blks); |
| 870 | |
| 871 | rblocks = RES_DINODE + ind_blocks + RES_STATFS + RES_QUOTA + |
| 872 | RES_RG_HDR + gfs2_rg_blocks(ip, data_blocks + ind_blocks); |
| 873 | if (gfs2_is_jdata(ip)) |
| 874 | rblocks += data_blocks ? data_blocks : 1; |
| 875 | |
| 876 | error = gfs2_trans_begin(sdp, rblocks, |
| 877 | PAGE_SIZE/sdp->sd_sb.sb_bsize); |
| 878 | if (error) |
| 879 | goto out_trans_fail; |
| 880 | |
| 881 | error = fallocate_chunk(inode, offset, max_bytes, mode); |
| 882 | gfs2_trans_end(sdp); |
| 883 | |
| 884 | if (error) |
| 885 | goto out_trans_fail; |
| 886 | |
| 887 | len -= max_bytes; |
| 888 | offset += max_bytes; |
| 889 | gfs2_inplace_release(ip); |
| 890 | gfs2_quota_unlock(ip); |
| 891 | } |
| 892 | |
| 893 | if (!(mode & FALLOC_FL_KEEP_SIZE) && (pos + count) > inode->i_size) { |
| 894 | i_size_write(inode, pos + count); |
| 895 | file_update_time(file); |
| 896 | mark_inode_dirty(inode); |
| 897 | } |
| 898 | |
| 899 | if ((file->f_flags & O_DSYNC) || IS_SYNC(file->f_mapping->host)) |
| 900 | return vfs_fsync_range(file, pos, pos + count - 1, |
| 901 | (file->f_flags & __O_SYNC) ? 0 : 1); |
| 902 | return 0; |
| 903 | |
| 904 | out_trans_fail: |
| 905 | gfs2_inplace_release(ip); |
| 906 | out_qunlock: |
| 907 | gfs2_quota_unlock(ip); |
| 908 | return error; |
| 909 | } |
| 910 | |
| 911 | static long gfs2_fallocate(struct file *file, int mode, loff_t offset, loff_t len) |
| 912 | { |
| 913 | struct inode *inode = file_inode(file); |
| 914 | struct gfs2_inode *ip = GFS2_I(inode); |
| 915 | struct gfs2_holder gh; |
| 916 | int ret; |
| 917 | |
| 918 | if ((mode & ~FALLOC_FL_KEEP_SIZE) || gfs2_is_jdata(ip)) |
| 919 | return -EOPNOTSUPP; |
| 920 | |
| 921 | inode_lock(inode); |
| 922 | |
| 923 | gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh); |
| 924 | ret = gfs2_glock_nq(&gh); |
| 925 | if (ret) |
| 926 | goto out_uninit; |
| 927 | |
| 928 | if (!(mode & FALLOC_FL_KEEP_SIZE) && |
| 929 | (offset + len) > inode->i_size) { |
| 930 | ret = inode_newsize_ok(inode, offset + len); |
| 931 | if (ret) |
| 932 | goto out_unlock; |
| 933 | } |
| 934 | |
| 935 | ret = get_write_access(inode); |
| 936 | if (ret) |
| 937 | goto out_unlock; |
| 938 | |
| 939 | ret = gfs2_rsqa_alloc(ip); |
| 940 | if (ret) |
| 941 | goto out_putw; |
| 942 | |
| 943 | ret = __gfs2_fallocate(file, mode, offset, len); |
| 944 | if (ret) |
| 945 | gfs2_rs_deltree(&ip->i_res); |
| 946 | |
| 947 | out_putw: |
| 948 | put_write_access(inode); |
| 949 | out_unlock: |
| 950 | gfs2_glock_dq(&gh); |
| 951 | out_uninit: |
| 952 | gfs2_holder_uninit(&gh); |
| 953 | inode_unlock(inode); |
| 954 | return ret; |
| 955 | } |
| 956 | |
| 957 | static ssize_t gfs2_file_splice_read(struct file *in, loff_t *ppos, |
| 958 | struct pipe_inode_info *pipe, size_t len, |
| 959 | unsigned int flags) |
| 960 | { |
| 961 | struct inode *inode = in->f_mapping->host; |
| 962 | struct gfs2_inode *ip = GFS2_I(inode); |
| 963 | struct gfs2_holder gh; |
| 964 | int ret; |
| 965 | |
| 966 | inode_lock(inode); |
| 967 | |
| 968 | ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &gh); |
| 969 | if (ret) { |
| 970 | inode_unlock(inode); |
| 971 | return ret; |
| 972 | } |
| 973 | |
| 974 | gfs2_glock_dq_uninit(&gh); |
| 975 | inode_unlock(inode); |
| 976 | |
| 977 | return generic_file_splice_read(in, ppos, pipe, len, flags); |
| 978 | } |
| 979 | |
| 980 | |
| 981 | static ssize_t gfs2_file_splice_write(struct pipe_inode_info *pipe, |
| 982 | struct file *out, loff_t *ppos, |
| 983 | size_t len, unsigned int flags) |
| 984 | { |
| 985 | int error; |
| 986 | struct gfs2_inode *ip = GFS2_I(out->f_mapping->host); |
| 987 | |
| 988 | error = gfs2_rsqa_alloc(ip); |
| 989 | if (error) |
| 990 | return (ssize_t)error; |
| 991 | |
| 992 | gfs2_size_hint(out, *ppos, len); |
| 993 | |
| 994 | return iter_file_splice_write(pipe, out, ppos, len, flags); |
| 995 | } |
| 996 | |
| 997 | #ifdef CONFIG_GFS2_FS_LOCKING_DLM |
| 998 | |
| 999 | /** |
| 1000 | * gfs2_lock - acquire/release a posix lock on a file |
| 1001 | * @file: the file pointer |
| 1002 | * @cmd: either modify or retrieve lock state, possibly wait |
| 1003 | * @fl: type and range of lock |
| 1004 | * |
| 1005 | * Returns: errno |
| 1006 | */ |
| 1007 | |
| 1008 | static int gfs2_lock(struct file *file, int cmd, struct file_lock *fl) |
| 1009 | { |
| 1010 | struct gfs2_inode *ip = GFS2_I(file->f_mapping->host); |
| 1011 | struct gfs2_sbd *sdp = GFS2_SB(file->f_mapping->host); |
| 1012 | struct lm_lockstruct *ls = &sdp->sd_lockstruct; |
| 1013 | |
| 1014 | if (!(fl->fl_flags & FL_POSIX)) |
| 1015 | return -ENOLCK; |
| 1016 | if (__mandatory_lock(&ip->i_inode) && fl->fl_type != F_UNLCK) |
| 1017 | return -ENOLCK; |
| 1018 | |
| 1019 | if (cmd == F_CANCELLK) { |
| 1020 | /* Hack: */ |
| 1021 | cmd = F_SETLK; |
| 1022 | fl->fl_type = F_UNLCK; |
| 1023 | } |
| 1024 | if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags))) { |
| 1025 | if (fl->fl_type == F_UNLCK) |
| 1026 | locks_lock_file_wait(file, fl); |
| 1027 | return -EIO; |
| 1028 | } |
| 1029 | if (IS_GETLK(cmd)) |
| 1030 | return dlm_posix_get(ls->ls_dlm, ip->i_no_addr, file, fl); |
| 1031 | else if (fl->fl_type == F_UNLCK) |
| 1032 | return dlm_posix_unlock(ls->ls_dlm, ip->i_no_addr, file, fl); |
| 1033 | else |
| 1034 | return dlm_posix_lock(ls->ls_dlm, ip->i_no_addr, file, cmd, fl); |
| 1035 | } |
| 1036 | |
| 1037 | static int do_flock(struct file *file, int cmd, struct file_lock *fl) |
| 1038 | { |
| 1039 | struct gfs2_file *fp = file->private_data; |
| 1040 | struct gfs2_holder *fl_gh = &fp->f_fl_gh; |
| 1041 | struct gfs2_inode *ip = GFS2_I(file_inode(file)); |
| 1042 | struct gfs2_glock *gl; |
| 1043 | unsigned int state; |
| 1044 | u16 flags; |
| 1045 | int error = 0; |
| 1046 | int sleeptime; |
| 1047 | |
| 1048 | state = (fl->fl_type == F_WRLCK) ? LM_ST_EXCLUSIVE : LM_ST_SHARED; |
| 1049 | flags = (IS_SETLKW(cmd) ? 0 : LM_FLAG_TRY_1CB) | GL_EXACT; |
| 1050 | |
| 1051 | mutex_lock(&fp->f_fl_mutex); |
| 1052 | |
| 1053 | gl = fl_gh->gh_gl; |
| 1054 | if (gl) { |
| 1055 | if (fl_gh->gh_state == state) |
| 1056 | goto out; |
| 1057 | locks_lock_file_wait(file, |
| 1058 | &(struct file_lock) { |
| 1059 | .fl_type = F_UNLCK, |
| 1060 | .fl_flags = FL_FLOCK |
| 1061 | }); |
| 1062 | gfs2_glock_dq(fl_gh); |
| 1063 | gfs2_holder_reinit(state, flags, fl_gh); |
| 1064 | } else { |
| 1065 | error = gfs2_glock_get(GFS2_SB(&ip->i_inode), ip->i_no_addr, |
| 1066 | &gfs2_flock_glops, CREATE, &gl); |
| 1067 | if (error) |
| 1068 | goto out; |
| 1069 | gfs2_holder_init(gl, state, flags, fl_gh); |
| 1070 | gfs2_glock_put(gl); |
| 1071 | } |
| 1072 | for (sleeptime = 1; sleeptime <= 4; sleeptime <<= 1) { |
| 1073 | error = gfs2_glock_nq(fl_gh); |
| 1074 | if (error != GLR_TRYFAILED) |
| 1075 | break; |
| 1076 | fl_gh->gh_flags = LM_FLAG_TRY | GL_EXACT; |
| 1077 | fl_gh->gh_error = 0; |
| 1078 | msleep(sleeptime); |
| 1079 | } |
| 1080 | if (error) { |
| 1081 | gfs2_holder_uninit(fl_gh); |
| 1082 | if (error == GLR_TRYFAILED) |
| 1083 | error = -EAGAIN; |
| 1084 | } else { |
| 1085 | error = locks_lock_file_wait(file, fl); |
| 1086 | gfs2_assert_warn(GFS2_SB(&ip->i_inode), !error); |
| 1087 | } |
| 1088 | |
| 1089 | out: |
| 1090 | mutex_unlock(&fp->f_fl_mutex); |
| 1091 | return error; |
| 1092 | } |
| 1093 | |
| 1094 | static void do_unflock(struct file *file, struct file_lock *fl) |
| 1095 | { |
| 1096 | struct gfs2_file *fp = file->private_data; |
| 1097 | struct gfs2_holder *fl_gh = &fp->f_fl_gh; |
| 1098 | |
| 1099 | mutex_lock(&fp->f_fl_mutex); |
| 1100 | locks_lock_file_wait(file, fl); |
| 1101 | if (fl_gh->gh_gl) { |
| 1102 | gfs2_glock_dq(fl_gh); |
| 1103 | gfs2_holder_uninit(fl_gh); |
| 1104 | } |
| 1105 | mutex_unlock(&fp->f_fl_mutex); |
| 1106 | } |
| 1107 | |
| 1108 | /** |
| 1109 | * gfs2_flock - acquire/release a flock lock on a file |
| 1110 | * @file: the file pointer |
| 1111 | * @cmd: either modify or retrieve lock state, possibly wait |
| 1112 | * @fl: type and range of lock |
| 1113 | * |
| 1114 | * Returns: errno |
| 1115 | */ |
| 1116 | |
| 1117 | static int gfs2_flock(struct file *file, int cmd, struct file_lock *fl) |
| 1118 | { |
| 1119 | if (!(fl->fl_flags & FL_FLOCK)) |
| 1120 | return -ENOLCK; |
| 1121 | if (fl->fl_type & LOCK_MAND) |
| 1122 | return -EOPNOTSUPP; |
| 1123 | |
| 1124 | if (fl->fl_type == F_UNLCK) { |
| 1125 | do_unflock(file, fl); |
| 1126 | return 0; |
| 1127 | } else { |
| 1128 | return do_flock(file, cmd, fl); |
| 1129 | } |
| 1130 | } |
| 1131 | |
| 1132 | const struct file_operations gfs2_file_fops = { |
| 1133 | .llseek = gfs2_llseek, |
| 1134 | .read_iter = generic_file_read_iter, |
| 1135 | .write_iter = gfs2_file_write_iter, |
| 1136 | .unlocked_ioctl = gfs2_ioctl, |
| 1137 | .mmap = gfs2_mmap, |
| 1138 | .open = gfs2_open, |
| 1139 | .release = gfs2_release, |
| 1140 | .fsync = gfs2_fsync, |
| 1141 | .lock = gfs2_lock, |
| 1142 | .flock = gfs2_flock, |
| 1143 | .splice_read = gfs2_file_splice_read, |
| 1144 | .splice_write = gfs2_file_splice_write, |
| 1145 | .setlease = simple_nosetlease, |
| 1146 | .fallocate = gfs2_fallocate, |
| 1147 | }; |
| 1148 | |
| 1149 | const struct file_operations gfs2_dir_fops = { |
| 1150 | .iterate_shared = gfs2_readdir, |
| 1151 | .unlocked_ioctl = gfs2_ioctl, |
| 1152 | .open = gfs2_open, |
| 1153 | .release = gfs2_release, |
| 1154 | .fsync = gfs2_fsync, |
| 1155 | .lock = gfs2_lock, |
| 1156 | .flock = gfs2_flock, |
| 1157 | .llseek = default_llseek, |
| 1158 | }; |
| 1159 | |
| 1160 | #endif /* CONFIG_GFS2_FS_LOCKING_DLM */ |
| 1161 | |
| 1162 | const struct file_operations gfs2_file_fops_nolock = { |
| 1163 | .llseek = gfs2_llseek, |
| 1164 | .read_iter = generic_file_read_iter, |
| 1165 | .write_iter = gfs2_file_write_iter, |
| 1166 | .unlocked_ioctl = gfs2_ioctl, |
| 1167 | .mmap = gfs2_mmap, |
| 1168 | .open = gfs2_open, |
| 1169 | .release = gfs2_release, |
| 1170 | .fsync = gfs2_fsync, |
| 1171 | .splice_read = gfs2_file_splice_read, |
| 1172 | .splice_write = gfs2_file_splice_write, |
| 1173 | .setlease = generic_setlease, |
| 1174 | .fallocate = gfs2_fallocate, |
| 1175 | }; |
| 1176 | |
| 1177 | const struct file_operations gfs2_dir_fops_nolock = { |
| 1178 | .iterate_shared = gfs2_readdir, |
| 1179 | .unlocked_ioctl = gfs2_ioctl, |
| 1180 | .open = gfs2_open, |
| 1181 | .release = gfs2_release, |
| 1182 | .fsync = gfs2_fsync, |
| 1183 | .llseek = default_llseek, |
| 1184 | }; |
| 1185 | |