fs/f2fs/compress.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * f2fs compress support
   4  *
   5  * Copyright (c) 2019 Chao Yu <chao@kernel.org>
   6  */
   7
   8 #include <linux/fs.h>
   9 #include <linux/f2fs_fs.h>
  10 #include <linux/writeback.h>
  11 #include <linux/backing-dev.h>
  12 #include <linux/lzo.h>
  13 #include <linux/lz4.h>
  14 #include <linux/zstd.h>
  15 #include <linux/pagevec.h>
  16
  17 #include "f2fs.h"
  18 #include "node.h"
  19 #include "segment.h"
  20 #include <trace/events/f2fs.h>
  21
  22 static struct kmem_cache *cic_entry_slab;
  23 static struct kmem_cache *dic_entry_slab;
  24
  25 static void *page_array_alloc(struct inode *inode, int nr)
  26 {
  27         struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
  28         unsigned int size = sizeof(struct page *) * nr;
  29
  30         if (likely(size <= sbi->page_array_slab_size))
  31                 return kmem_cache_zalloc(sbi->page_array_slab, GFP_NOFS);
  32         return f2fs_kzalloc(sbi, size, GFP_NOFS);
  33 }
  34
  35 static void page_array_free(struct inode *inode, void *pages, int nr)
  36 {
  37         struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
  38         unsigned int size = sizeof(struct page *) * nr;
  39
  40         if (!pages)
  41                 return;
  42
  43         if (likely(size <= sbi->page_array_slab_size))
  44                 kmem_cache_free(sbi->page_array_slab, pages);
  45         else
  46                 kfree(pages);
  47 }
  48
  49 struct f2fs_compress_ops {
  50         int (*init_compress_ctx)(struct compress_ctx *cc);
  51         void (*destroy_compress_ctx)(struct compress_ctx *cc);
  52         int (*compress_pages)(struct compress_ctx *cc);
  53         int (*init_decompress_ctx)(struct decompress_io_ctx *dic);
  54         void (*destroy_decompress_ctx)(struct decompress_io_ctx *dic);
  55         int (*decompress_pages)(struct decompress_io_ctx *dic);
  56 };
  57
  58 static unsigned int offset_in_cluster(struct compress_ctx *cc, pgoff_t index)
  59 {
  60         return index & (cc->cluster_size - 1);
  61 }
  62
  63 static pgoff_t cluster_idx(struct compress_ctx *cc, pgoff_t index)
  64 {
  65         return index >> cc->log_cluster_size;
  66 }
  67
  68 static pgoff_t start_idx_of_cluster(struct compress_ctx *cc)
  69 {
  70         return cc->cluster_idx << cc->log_cluster_size;
  71 }
  72
  73 bool f2fs_is_compressed_page(struct page *page)
  74 {
  75         if (!PagePrivate(page))
  76                 return false;
  77         if (!page_private(page))
  78                 return false;
  79         if (page_private_nonpointer(page))
  80                 return false;
  81
  82         f2fs_bug_on(F2FS_M_SB(page->mapping),
  83                 *((u32 *)page_private(page)) != F2FS_COMPRESSED_PAGE_MAGIC);
  84         return true;
  85 }
  86
  87 static void f2fs_set_compressed_page(struct page *page,
  88                 struct inode *inode, pgoff_t index, void *data)
  89 {
  90         attach_page_private(page, (void *)data);
  91
  92         /* i_crypto_info and iv index */
  93         page->index = index;
  94         page->mapping = inode->i_mapping;
  95 }
  96
  97 static void f2fs_drop_rpages(struct compress_ctx *cc, int len, bool unlock)
  98 {
  99         int i;
 100
 101         for (i = 0; i < len; i++) {
 102                 if (!cc->rpages[i])
 103                         continue;
 104                 if (unlock)
 105                         unlock_page(cc->rpages[i]);
 106                 else
 107                         put_page(cc->rpages[i]);
 108         }
 109 }
 110
 111 static void f2fs_put_rpages(struct compress_ctx *cc)
 112 {
 113         f2fs_drop_rpages(cc, cc->cluster_size, false);
 114 }
 115
 116 static void f2fs_unlock_rpages(struct compress_ctx *cc, int len)
 117 {
 118         f2fs_drop_rpages(cc, len, true);
 119 }
 120
 121 static void f2fs_put_rpages_wbc(struct compress_ctx *cc,
 122                 struct writeback_control *wbc, bool redirty, int unlock)
 123 {
 124         unsigned int i;
 125
 126         for (i = 0; i < cc->cluster_size; i++) {
 127                 if (!cc->rpages[i])
 128                         continue;
 129                 if (redirty)
 130                         redirty_page_for_writepage(wbc, cc->rpages[i]);
 131                 f2fs_put_page(cc->rpages[i], unlock);
 132         }
 133 }
 134
 135 struct page *f2fs_compress_control_page(struct page *page)
 136 {
 137         return ((struct compress_io_ctx *)page_private(page))->rpages[0];
 138 }
 139
 140 int f2fs_init_compress_ctx(struct compress_ctx *cc)
 141 {
 142         if (cc->rpages)
 143                 return 0;
 144
 145         cc->rpages = page_array_alloc(cc->inode, cc->cluster_size);
 146         return cc->rpages ? 0 : -ENOMEM;
 147 }
 148
 149 void f2fs_destroy_compress_ctx(struct compress_ctx *cc, bool reuse)
 150 {
 151         page_array_free(cc->inode, cc->rpages, cc->cluster_size);
 152         cc->rpages = NULL;
 153         cc->nr_rpages = 0;
 154         cc->nr_cpages = 0;
 155         if (!reuse)
 156                 cc->cluster_idx = NULL_CLUSTER;
 157 }
 158
 159 void f2fs_compress_ctx_add_page(struct compress_ctx *cc, struct page *page)
 160 {
 161         unsigned int cluster_ofs;
 162
 163         if (!f2fs_cluster_can_merge_page(cc, page->index))
 164                 f2fs_bug_on(F2FS_I_SB(cc->inode), 1);
 165
 166         cluster_ofs = offset_in_cluster(cc, page->index);
 167         cc->rpages[cluster_ofs] = page;
 168         cc->nr_rpages++;
 169         cc->cluster_idx = cluster_idx(cc, page->index);
 170 }
 171
 172 #ifdef CONFIG_F2FS_FS_LZO
 173 static int lzo_init_compress_ctx(struct compress_ctx *cc)
 174 {
 175         cc->private = f2fs_kvmalloc(F2FS_I_SB(cc->inode),
 176                                 LZO1X_MEM_COMPRESS, GFP_NOFS);
 177         if (!cc->private)
 178                 return -ENOMEM;
 179
 180         cc->clen = lzo1x_worst_compress(PAGE_SIZE << cc->log_cluster_size);
 181         return 0;
 182 }
 183
 184 static void lzo_destroy_compress_ctx(struct compress_ctx *cc)
 185 {
 186         kvfree(cc->private);
 187         cc->private = NULL;
 188 }
 189
 190 static int lzo_compress_pages(struct compress_ctx *cc)
 191 {
 192         int ret;
 193
 194         ret = lzo1x_1_compress(cc->rbuf, cc->rlen, cc->cbuf->cdata,
 195                                         &cc->clen, cc->private);
 196         if (ret != LZO_E_OK) {
 197                 printk_ratelimited("%sF2FS-fs (%s): lzo compress failed, ret:%d\n",
 198                                 KERN_ERR, F2FS_I_SB(cc->inode)->sb->s_id, ret);
 199                 return -EIO;
 200         }
 201         return 0;
 202 }
 203
 204 static int lzo_decompress_pages(struct decompress_io_ctx *dic)
 205 {
 206         int ret;
 207
 208         ret = lzo1x_decompress_safe(dic->cbuf->cdata, dic->clen,
 209                                                 dic->rbuf, &dic->rlen);
 210         if (ret != LZO_E_OK) {
 211                 printk_ratelimited("%sF2FS-fs (%s): lzo decompress failed, ret:%d\n",
 212                                 KERN_ERR, F2FS_I_SB(dic->inode)->sb->s_id, ret);
 213                 return -EIO;
 214         }
 215
 216         if (dic->rlen != PAGE_SIZE << dic->log_cluster_size) {
 217                 printk_ratelimited("%sF2FS-fs (%s): lzo invalid rlen:%zu, "
 218                                         "expected:%lu\n", KERN_ERR,
 219                                         F2FS_I_SB(dic->inode)->sb->s_id,
 220                                         dic->rlen,
 221                                         PAGE_SIZE << dic->log_cluster_size);
 222                 return -EIO;
 223         }
 224         return 0;
 225 }
 226
 227 static const struct f2fs_compress_ops f2fs_lzo_ops = {
 228         .init_compress_ctx      = lzo_init_compress_ctx,
 229         .destroy_compress_ctx   = lzo_destroy_compress_ctx,
 230         .compress_pages         = lzo_compress_pages,
 231         .decompress_pages       = lzo_decompress_pages,
 232 };
 233 #endif
 234
 235 #ifdef CONFIG_F2FS_FS_LZ4
 236 static int lz4_init_compress_ctx(struct compress_ctx *cc)
 237 {
 238         unsigned int size = LZ4_MEM_COMPRESS;
 239
 240 #ifdef CONFIG_F2FS_FS_LZ4HC
 241         if (F2FS_I(cc->inode)->i_compress_flag >> COMPRESS_LEVEL_OFFSET)
 242                 size = LZ4HC_MEM_COMPRESS;
 243 #endif
 244
 245         cc->private = f2fs_kvmalloc(F2FS_I_SB(cc->inode), size, GFP_NOFS);
 246         if (!cc->private)
 247                 return -ENOMEM;
 248
 249         /*
 250          * we do not change cc->clen to LZ4_compressBound(inputsize) to
 251          * adapt worst compress case, because lz4 compressor can handle
 252          * output budget properly.
 253          */
 254         cc->clen = cc->rlen - PAGE_SIZE - COMPRESS_HEADER_SIZE;
 255         return 0;
 256 }
 257
 258 static void lz4_destroy_compress_ctx(struct compress_ctx *cc)
 259 {
 260         kvfree(cc->private);
 261         cc->private = NULL;
 262 }
 263
 264 #ifdef CONFIG_F2FS_FS_LZ4HC
 265 static int lz4hc_compress_pages(struct compress_ctx *cc)
 266 {
 267         unsigned char level = F2FS_I(cc->inode)->i_compress_flag >>
 268                                                 COMPRESS_LEVEL_OFFSET;
 269         int len;
 270
 271         if (level)
 272                 len = LZ4_compress_HC(cc->rbuf, cc->cbuf->cdata, cc->rlen,
 273                                         cc->clen, level, cc->private);
 274         else
 275                 len = LZ4_compress_default(cc->rbuf, cc->cbuf->cdata, cc->rlen,
 276                                                 cc->clen, cc->private);
 277         if (!len)
 278                 return -EAGAIN;
 279
 280         cc->clen = len;
 281         return 0;
 282 }
 283 #endif
 284
 285 static int lz4_compress_pages(struct compress_ctx *cc)
 286 {
 287         int len;
 288
 289 #ifdef CONFIG_F2FS_FS_LZ4HC
 290         return lz4hc_compress_pages(cc);
 291 #endif
 292         len = LZ4_compress_default(cc->rbuf, cc->cbuf->cdata, cc->rlen,
 293                                                 cc->clen, cc->private);
 294         if (!len)
 295                 return -EAGAIN;
 296
 297         cc->clen = len;
 298         return 0;
 299 }
 300
 301 static int lz4_decompress_pages(struct decompress_io_ctx *dic)
 302 {
 303         int ret;
 304
 305         ret = LZ4_decompress_safe(dic->cbuf->cdata, dic->rbuf,
 306                                                 dic->clen, dic->rlen);
 307         if (ret < 0) {
 308                 printk_ratelimited("%sF2FS-fs (%s): lz4 decompress failed, ret:%d\n",
 309                                 KERN_ERR, F2FS_I_SB(dic->inode)->sb->s_id, ret);
 310                 return -EIO;
 311         }
 312
 313         if (ret != PAGE_SIZE << dic->log_cluster_size) {
 314                 printk_ratelimited("%sF2FS-fs (%s): lz4 invalid rlen:%zu, "
 315                                         "expected:%lu\n", KERN_ERR,
 316                                         F2FS_I_SB(dic->inode)->sb->s_id,
 317                                         dic->rlen,
 318                                         PAGE_SIZE << dic->log_cluster_size);
 319                 return -EIO;
 320         }
 321         return 0;
 322 }
 323
 324 static const struct f2fs_compress_ops f2fs_lz4_ops = {
 325         .init_compress_ctx      = lz4_init_compress_ctx,
 326         .destroy_compress_ctx   = lz4_destroy_compress_ctx,
 327         .compress_pages         = lz4_compress_pages,
 328         .decompress_pages       = lz4_decompress_pages,
 329 };
 330 #endif
 331
 332 #ifdef CONFIG_F2FS_FS_ZSTD
 333 #define F2FS_ZSTD_DEFAULT_CLEVEL        1
 334
 335 static int zstd_init_compress_ctx(struct compress_ctx *cc)
 336 {
 337         ZSTD_parameters params;
 338         ZSTD_CStream *stream;
 339         void *workspace;
 340         unsigned int workspace_size;
 341         unsigned char level = F2FS_I(cc->inode)->i_compress_flag >>
 342                                                 COMPRESS_LEVEL_OFFSET;
 343
 344         if (!level)
 345                 level = F2FS_ZSTD_DEFAULT_CLEVEL;
 346
 347         params = ZSTD_getParams(level, cc->rlen, 0);
 348         workspace_size = ZSTD_CStreamWorkspaceBound(params.cParams);
 349
 350         workspace = f2fs_kvmalloc(F2FS_I_SB(cc->inode),
 351                                         workspace_size, GFP_NOFS);
 352         if (!workspace)
 353                 return -ENOMEM;
 354
 355         stream = ZSTD_initCStream(params, 0, workspace, workspace_size);
 356         if (!stream) {
 357                 printk_ratelimited("%sF2FS-fs (%s): %s ZSTD_initCStream failed\n",
 358                                 KERN_ERR, F2FS_I_SB(cc->inode)->sb->s_id,
 359                                 __func__);
 360                 kvfree(workspace);
 361                 return -EIO;
 362         }
 363
 364         cc->private = workspace;
 365         cc->private2 = stream;
 366
 367         cc->clen = cc->rlen - PAGE_SIZE - COMPRESS_HEADER_SIZE;
 368         return 0;
 369 }
 370
 371 static void zstd_destroy_compress_ctx(struct compress_ctx *cc)
 372 {
 373         kvfree(cc->private);
 374         cc->private = NULL;
 375         cc->private2 = NULL;
 376 }
 377
 378 static int zstd_compress_pages(struct compress_ctx *cc)
 379 {
 380         ZSTD_CStream *stream = cc->private2;
 381         ZSTD_inBuffer inbuf;
 382         ZSTD_outBuffer outbuf;
 383         int src_size = cc->rlen;
 384         int dst_size = src_size - PAGE_SIZE - COMPRESS_HEADER_SIZE;
 385         int ret;
 386
 387         inbuf.pos = 0;
 388         inbuf.src = cc->rbuf;
 389         inbuf.size = src_size;
 390
 391         outbuf.pos = 0;
 392         outbuf.dst = cc->cbuf->cdata;
 393         outbuf.size = dst_size;
 394
 395         ret = ZSTD_compressStream(stream, &outbuf, &inbuf);
 396         if (ZSTD_isError(ret)) {
 397                 printk_ratelimited("%sF2FS-fs (%s): %s ZSTD_compressStream failed, ret: %d\n",
 398                                 KERN_ERR, F2FS_I_SB(cc->inode)->sb->s_id,
 399                                 __func__, ZSTD_getErrorCode(ret));
 400                 return -EIO;
 401         }
 402
 403         ret = ZSTD_endStream(stream, &outbuf);
 404         if (ZSTD_isError(ret)) {
 405                 printk_ratelimited("%sF2FS-fs (%s): %s ZSTD_endStream returned %d\n",
 406                                 KERN_ERR, F2FS_I_SB(cc->inode)->sb->s_id,
 407                                 __func__, ZSTD_getErrorCode(ret));
 408                 return -EIO;
 409         }
 410
 411         /*
 412          * there is compressed data remained in intermediate buffer due to
 413          * no more space in cbuf.cdata
 414          */
 415         if (ret)
 416                 return -EAGAIN;
 417
 418         cc->clen = outbuf.pos;
 419         return 0;
 420 }
 421
 422 static int zstd_init_decompress_ctx(struct decompress_io_ctx *dic)
 423 {
 424         ZSTD_DStream *stream;
 425         void *workspace;
 426         unsigned int workspace_size;
 427         unsigned int max_window_size =
 428                         MAX_COMPRESS_WINDOW_SIZE(dic->log_cluster_size);
 429
 430         workspace_size = ZSTD_DStreamWorkspaceBound(max_window_size);
 431
 432         workspace = f2fs_kvmalloc(F2FS_I_SB(dic->inode),
 433                                         workspace_size, GFP_NOFS);
 434         if (!workspace)
 435                 return -ENOMEM;
 436
 437         stream = ZSTD_initDStream(max_window_size, workspace, workspace_size);
 438         if (!stream) {
 439                 printk_ratelimited("%sF2FS-fs (%s): %s ZSTD_initDStream failed\n",
 440                                 KERN_ERR, F2FS_I_SB(dic->inode)->sb->s_id,
 441                                 __func__);
 442                 kvfree(workspace);
 443                 return -EIO;
 444         }
 445
 446         dic->private = workspace;
 447         dic->private2 = stream;
 448
 449         return 0;
 450 }
 451
 452 static void zstd_destroy_decompress_ctx(struct decompress_io_ctx *dic)
 453 {
 454         kvfree(dic->private);
 455         dic->private = NULL;
 456         dic->private2 = NULL;
 457 }
 458
 459 static int zstd_decompress_pages(struct decompress_io_ctx *dic)
 460 {
 461         ZSTD_DStream *stream = dic->private2;
 462         ZSTD_inBuffer inbuf;
 463         ZSTD_outBuffer outbuf;
 464         int ret;
 465
 466         inbuf.pos = 0;
 467         inbuf.src = dic->cbuf->cdata;
 468         inbuf.size = dic->clen;
 469
 470         outbuf.pos = 0;
 471         outbuf.dst = dic->rbuf;
 472         outbuf.size = dic->rlen;
 473
 474         ret = ZSTD_decompressStream(stream, &outbuf, &inbuf);
 475         if (ZSTD_isError(ret)) {
 476                 printk_ratelimited("%sF2FS-fs (%s): %s ZSTD_compressStream failed, ret: %d\n",
 477                                 KERN_ERR, F2FS_I_SB(dic->inode)->sb->s_id,
 478                                 __func__, ZSTD_getErrorCode(ret));
 479                 return -EIO;
 480         }
 481
 482         if (dic->rlen != outbuf.pos) {
 483                 printk_ratelimited("%sF2FS-fs (%s): %s ZSTD invalid rlen:%zu, "
 484                                 "expected:%lu\n", KERN_ERR,
 485                                 F2FS_I_SB(dic->inode)->sb->s_id,
 486                                 __func__, dic->rlen,
 487                                 PAGE_SIZE << dic->log_cluster_size);
 488                 return -EIO;
 489         }
 490
 491         return 0;
 492 }
 493
 494 static const struct f2fs_compress_ops f2fs_zstd_ops = {
 495         .init_compress_ctx      = zstd_init_compress_ctx,
 496         .destroy_compress_ctx   = zstd_destroy_compress_ctx,
 497         .compress_pages         = zstd_compress_pages,
 498         .init_decompress_ctx    = zstd_init_decompress_ctx,
 499         .destroy_decompress_ctx = zstd_destroy_decompress_ctx,
 500         .decompress_pages       = zstd_decompress_pages,
 501 };
 502 #endif
 503
 504 #ifdef CONFIG_F2FS_FS_LZO
 505 #ifdef CONFIG_F2FS_FS_LZORLE
 506 static int lzorle_compress_pages(struct compress_ctx *cc)
 507 {
 508         int ret;
 509
 510         ret = lzorle1x_1_compress(cc->rbuf, cc->rlen, cc->cbuf->cdata,
 511                                         &cc->clen, cc->private);
 512         if (ret != LZO_E_OK) {
 513                 printk_ratelimited("%sF2FS-fs (%s): lzo-rle compress failed, ret:%d\n",
 514                                 KERN_ERR, F2FS_I_SB(cc->inode)->sb->s_id, ret);
 515                 return -EIO;
 516         }
 517         return 0;
 518 }
 519
 520 static const struct f2fs_compress_ops f2fs_lzorle_ops = {
 521         .init_compress_ctx      = lzo_init_compress_ctx,
 522         .destroy_compress_ctx   = lzo_destroy_compress_ctx,
 523         .compress_pages         = lzorle_compress_pages,
 524         .decompress_pages       = lzo_decompress_pages,
 525 };
 526 #endif
 527 #endif
 528
 529 static const struct f2fs_compress_ops *f2fs_cops[COMPRESS_MAX] = {
 530 #ifdef CONFIG_F2FS_FS_LZO
 531         &f2fs_lzo_ops,
 532 #else
 533         NULL,
 534 #endif
 535 #ifdef CONFIG_F2FS_FS_LZ4
 536         &f2fs_lz4_ops,
 537 #else
 538         NULL,
 539 #endif
 540 #ifdef CONFIG_F2FS_FS_ZSTD
 541         &f2fs_zstd_ops,
 542 #else
 543         NULL,
 544 #endif
 545 #if defined(CONFIG_F2FS_FS_LZO) && defined(CONFIG_F2FS_FS_LZORLE)
 546         &f2fs_lzorle_ops,
 547 #else
 548         NULL,
 549 #endif
 550 };
 551
 552 bool f2fs_is_compress_backend_ready(struct inode *inode)
 553 {
 554         if (!f2fs_compressed_file(inode))
 555                 return true;
 556         return f2fs_cops[F2FS_I(inode)->i_compress_algorithm];
 557 }
 558
 559 static mempool_t *compress_page_pool;
 560 static int num_compress_pages = 512;
 561 module_param(num_compress_pages, uint, 0444);
 562 MODULE_PARM_DESC(num_compress_pages,
 563                 "Number of intermediate compress pages to preallocate");
 564
 565 int f2fs_init_compress_mempool(void)
 566 {
 567         compress_page_pool = mempool_create_page_pool(num_compress_pages, 0);
 568         if (!compress_page_pool)
 569                 return -ENOMEM;
 570
 571         return 0;
 572 }
 573
 574 void f2fs_destroy_compress_mempool(void)
 575 {
 576         mempool_destroy(compress_page_pool);
 577 }
 578
 579 static struct page *f2fs_compress_alloc_page(void)
 580 {
 581         struct page *page;
 582
 583         page = mempool_alloc(compress_page_pool, GFP_NOFS);
 584         lock_page(page);
 585
 586         return page;
 587 }
 588
 589 static void f2fs_compress_free_page(struct page *page)
 590 {
 591         if (!page)
 592                 return;
 593         detach_page_private(page);
 594         page->mapping = NULL;
 595         unlock_page(page);
 596         mempool_free(page, compress_page_pool);
 597 }
 598
 599 #define MAX_VMAP_RETRIES        3
 600
 601 static void *f2fs_vmap(struct page **pages, unsigned int count)
 602 {
 603         int i;
 604         void *buf = NULL;
 605
 606         for (i = 0; i < MAX_VMAP_RETRIES; i++) {
 607                 buf = vm_map_ram(pages, count, -1);
 608                 if (buf)
 609                         break;
 610                 vm_unmap_aliases();
 611         }
 612         return buf;
 613 }
 614
 615 static int f2fs_compress_pages(struct compress_ctx *cc)
 616 {
 617         struct f2fs_inode_info *fi = F2FS_I(cc->inode);
 618         const struct f2fs_compress_ops *cops =
 619                                 f2fs_cops[fi->i_compress_algorithm];
 620         unsigned int max_len, new_nr_cpages;
 621         struct page **new_cpages;
 622         u32 chksum = 0;
 623         int i, ret;
 624
 625         trace_f2fs_compress_pages_start(cc->inode, cc->cluster_idx,
 626                                 cc->cluster_size, fi->i_compress_algorithm);
 627
 628         if (cops->init_compress_ctx) {
 629                 ret = cops->init_compress_ctx(cc);
 630                 if (ret)
 631                         goto out;
 632         }
 633
 634         max_len = COMPRESS_HEADER_SIZE + cc->clen;
 635         cc->nr_cpages = DIV_ROUND_UP(max_len, PAGE_SIZE);
 636
 637         cc->cpages = page_array_alloc(cc->inode, cc->nr_cpages);
 638         if (!cc->cpages) {
 639                 ret = -ENOMEM;
 640                 goto destroy_compress_ctx;
 641         }
 642
 643         for (i = 0; i < cc->nr_cpages; i++) {
 644                 cc->cpages[i] = f2fs_compress_alloc_page();
 645                 if (!cc->cpages[i]) {
 646                         ret = -ENOMEM;
 647                         goto out_free_cpages;
 648                 }
 649         }
 650
 651         cc->rbuf = f2fs_vmap(cc->rpages, cc->cluster_size);
 652         if (!cc->rbuf) {
 653                 ret = -ENOMEM;
 654                 goto out_free_cpages;
 655         }
 656
 657         cc->cbuf = f2fs_vmap(cc->cpages, cc->nr_cpages);
 658         if (!cc->cbuf) {
 659                 ret = -ENOMEM;
 660                 goto out_vunmap_rbuf;
 661         }
 662
 663         ret = cops->compress_pages(cc);
 664         if (ret)
 665                 goto out_vunmap_cbuf;
 666
 667         max_len = PAGE_SIZE * (cc->cluster_size - 1) - COMPRESS_HEADER_SIZE;
 668
 669         if (cc->clen > max_len) {
 670                 ret = -EAGAIN;
 671                 goto out_vunmap_cbuf;
 672         }
 673
 674         cc->cbuf->clen = cpu_to_le32(cc->clen);
 675
 676         if (fi->i_compress_flag & 1 << COMPRESS_CHKSUM)
 677                 chksum = f2fs_crc32(F2FS_I_SB(cc->inode),
 678                                         cc->cbuf->cdata, cc->clen);
 679         cc->cbuf->chksum = cpu_to_le32(chksum);
 680
 681         for (i = 0; i < COMPRESS_DATA_RESERVED_SIZE; i++)
 682                 cc->cbuf->reserved[i] = cpu_to_le32(0);
 683
 684         new_nr_cpages = DIV_ROUND_UP(cc->clen + COMPRESS_HEADER_SIZE, PAGE_SIZE);
 685
 686         /* Now we're going to cut unnecessary tail pages */
 687         new_cpages = page_array_alloc(cc->inode, new_nr_cpages);
 688         if (!new_cpages) {
 689                 ret = -ENOMEM;
 690                 goto out_vunmap_cbuf;
 691         }
 692
 693         /* zero out any unused part of the last page */
 694         memset(&cc->cbuf->cdata[cc->clen], 0,
 695                         (new_nr_cpages * PAGE_SIZE) -
 696                         (cc->clen + COMPRESS_HEADER_SIZE));
 697
 698         vm_unmap_ram(cc->cbuf, cc->nr_cpages);
 699         vm_unmap_ram(cc->rbuf, cc->cluster_size);
 700
 701         for (i = 0; i < cc->nr_cpages; i++) {
 702                 if (i < new_nr_cpages) {
 703                         new_cpages[i] = cc->cpages[i];
 704                         continue;
 705                 }
 706                 f2fs_compress_free_page(cc->cpages[i]);
 707                 cc->cpages[i] = NULL;
 708         }
 709
 710         if (cops->destroy_compress_ctx)
 711                 cops->destroy_compress_ctx(cc);
 712
 713         page_array_free(cc->inode, cc->cpages, cc->nr_cpages);
 714         cc->cpages = new_cpages;
 715         cc->nr_cpages = new_nr_cpages;
 716
 717         trace_f2fs_compress_pages_end(cc->inode, cc->cluster_idx,
 718                                                         cc->clen, ret);
 719         return 0;
 720
 721 out_vunmap_cbuf:
 722         vm_unmap_ram(cc->cbuf, cc->nr_cpages);
 723 out_vunmap_rbuf:
 724         vm_unmap_ram(cc->rbuf, cc->cluster_size);
 725 out_free_cpages:
 726         for (i = 0; i < cc->nr_cpages; i++) {
 727                 if (cc->cpages[i])
 728                         f2fs_compress_free_page(cc->cpages[i]);
 729         }
 730         page_array_free(cc->inode, cc->cpages, cc->nr_cpages);
 731         cc->cpages = NULL;
 732 destroy_compress_ctx:
 733         if (cops->destroy_compress_ctx)
 734                 cops->destroy_compress_ctx(cc);
 735 out:
 736         trace_f2fs_compress_pages_end(cc->inode, cc->cluster_idx,
 737                                                         cc->clen, ret);
 738         return ret;
 739 }
 740
 741 void f2fs_decompress_cluster(struct decompress_io_ctx *dic)
 742 {
 743         struct f2fs_sb_info *sbi = F2FS_I_SB(dic->inode);
 744         struct f2fs_inode_info *fi = F2FS_I(dic->inode);
 745         const struct f2fs_compress_ops *cops =
 746                         f2fs_cops[fi->i_compress_algorithm];
 747         int ret;
 748         int i;
 749
 750         trace_f2fs_decompress_pages_start(dic->inode, dic->cluster_idx,
 751                                 dic->cluster_size, fi->i_compress_algorithm);
 752
 753         if (dic->failed) {
 754                 ret = -EIO;
 755                 goto out_end_io;
 756         }
 757
 758         dic->tpages = page_array_alloc(dic->inode, dic->cluster_size);
 759         if (!dic->tpages) {
 760                 ret = -ENOMEM;
 761                 goto out_end_io;
 762         }
 763
 764         for (i = 0; i < dic->cluster_size; i++) {
 765                 if (dic->rpages[i]) {
 766                         dic->tpages[i] = dic->rpages[i];
 767                         continue;
 768                 }
 769
 770                 dic->tpages[i] = f2fs_compress_alloc_page();
 771                 if (!dic->tpages[i]) {
 772                         ret = -ENOMEM;
 773                         goto out_end_io;
 774                 }
 775         }
 776
 777         if (cops->init_decompress_ctx) {
 778                 ret = cops->init_decompress_ctx(dic);
 779                 if (ret)
 780                         goto out_end_io;
 781         }
 782
 783         dic->rbuf = f2fs_vmap(dic->tpages, dic->cluster_size);
 784         if (!dic->rbuf) {
 785                 ret = -ENOMEM;
 786                 goto out_destroy_decompress_ctx;
 787         }
 788
 789         dic->cbuf = f2fs_vmap(dic->cpages, dic->nr_cpages);
 790         if (!dic->cbuf) {
 791                 ret = -ENOMEM;
 792                 goto out_vunmap_rbuf;
 793         }
 794
 795         dic->clen = le32_to_cpu(dic->cbuf->clen);
 796         dic->rlen = PAGE_SIZE << dic->log_cluster_size;
 797
 798         if (dic->clen > PAGE_SIZE * dic->nr_cpages - COMPRESS_HEADER_SIZE) {
 799                 ret = -EFSCORRUPTED;
 800                 goto out_vunmap_cbuf;
 801         }
 802
 803         ret = cops->decompress_pages(dic);
 804
 805         if (!ret && (fi->i_compress_flag & 1 << COMPRESS_CHKSUM)) {
 806                 u32 provided = le32_to_cpu(dic->cbuf->chksum);
 807                 u32 calculated = f2fs_crc32(sbi, dic->cbuf->cdata, dic->clen);
 808
 809                 if (provided != calculated) {
 810                         if (!is_inode_flag_set(dic->inode, FI_COMPRESS_CORRUPT)) {
 811                                 set_inode_flag(dic->inode, FI_COMPRESS_CORRUPT);
 812                                 printk_ratelimited(
 813                                         "%sF2FS-fs (%s): checksum invalid, nid = %lu, %x vs %x",
 814                                         KERN_INFO, sbi->sb->s_id, dic->inode->i_ino,
 815                                         provided, calculated);
 816                         }
 817                         set_sbi_flag(sbi, SBI_NEED_FSCK);
 818                 }
 819         }
 820
 821 out_vunmap_cbuf:
 822         vm_unmap_ram(dic->cbuf, dic->nr_cpages);
 823 out_vunmap_rbuf:
 824         vm_unmap_ram(dic->rbuf, dic->cluster_size);
 825 out_destroy_decompress_ctx:
 826         if (cops->destroy_decompress_ctx)
 827                 cops->destroy_decompress_ctx(dic);
 828 out_end_io:
 829         trace_f2fs_decompress_pages_end(dic->inode, dic->cluster_idx,
 830                                                         dic->clen, ret);
 831         f2fs_decompress_end_io(dic, ret);
 832 }
 833
 834 /*
 835  * This is called when a page of a compressed cluster has been read from disk
 836  * (or failed to be read from disk).  It checks whether this page was the last
 837  * page being waited on in the cluster, and if so, it decompresses the cluster
 838  * (or in the case of a failure, cleans up without actually decompressing).
 839  */
 840 void f2fs_end_read_compressed_page(struct page *page, bool failed,
 841                                                 block_t blkaddr)
 842 {
 843         struct decompress_io_ctx *dic =
 844                         (struct decompress_io_ctx *)page_private(page);
 845         struct f2fs_sb_info *sbi = F2FS_I_SB(dic->inode);
 846
 847         dec_page_count(sbi, F2FS_RD_DATA);
 848
 849         if (failed)
 850                 WRITE_ONCE(dic->failed, true);
 851         else if (blkaddr)
 852                 f2fs_cache_compressed_page(sbi, page,
 853                                         dic->inode->i_ino, blkaddr);
 854
 855         if (atomic_dec_and_test(&dic->remaining_pages))
 856                 f2fs_decompress_cluster(dic);
 857 }
 858
 859 static bool is_page_in_cluster(struct compress_ctx *cc, pgoff_t index)
 860 {
 861         if (cc->cluster_idx == NULL_CLUSTER)
 862                 return true;
 863         return cc->cluster_idx == cluster_idx(cc, index);
 864 }
 865
 866 bool f2fs_cluster_is_empty(struct compress_ctx *cc)
 867 {
 868         return cc->nr_rpages == 0;
 869 }
 870
 871 static bool f2fs_cluster_is_full(struct compress_ctx *cc)
 872 {
 873         return cc->cluster_size == cc->nr_rpages;
 874 }
 875
 876 bool f2fs_cluster_can_merge_page(struct compress_ctx *cc, pgoff_t index)
 877 {
 878         if (f2fs_cluster_is_empty(cc))
 879                 return true;
 880         return is_page_in_cluster(cc, index);
 881 }
 882
 883 static bool cluster_has_invalid_data(struct compress_ctx *cc)
 884 {
 885         loff_t i_size = i_size_read(cc->inode);
 886         unsigned nr_pages = DIV_ROUND_UP(i_size, PAGE_SIZE);
 887         int i;
 888
 889         for (i = 0; i < cc->cluster_size; i++) {
 890                 struct page *page = cc->rpages[i];
 891
 892                 f2fs_bug_on(F2FS_I_SB(cc->inode), !page);
 893
 894                 /* beyond EOF */
 895                 if (page->index >= nr_pages)
 896                         return true;
 897         }
 898         return false;
 899 }
 900
 901 static int __f2fs_cluster_blocks(struct inode *inode,
 902                                 unsigned int cluster_idx, bool compr)
 903 {
 904         struct dnode_of_data dn;
 905         unsigned int cluster_size = F2FS_I(inode)->i_cluster_size;
 906         unsigned int start_idx = cluster_idx <<
 907                                 F2FS_I(inode)->i_log_cluster_size;
 908         int ret;
 909
 910         set_new_dnode(&dn, inode, NULL, NULL, 0);
 911         ret = f2fs_get_dnode_of_data(&dn, start_idx, LOOKUP_NODE);
 912         if (ret) {
 913                 if (ret == -ENOENT)
 914                         ret = 0;
 915                 goto fail;
 916         }
 917
 918         if (dn.data_blkaddr == COMPRESS_ADDR) {
 919                 int i;
 920
 921                 ret = 1;
 922                 for (i = 1; i < cluster_size; i++) {
 923                         block_t blkaddr;
 924
 925                         blkaddr = data_blkaddr(dn.inode,
 926                                         dn.node_page, dn.ofs_in_node + i);
 927                         if (compr) {
 928                                 if (__is_valid_data_blkaddr(blkaddr))
 929                                         ret++;
 930                         } else {
 931                                 if (blkaddr != NULL_ADDR)
 932                                         ret++;
 933                         }
 934                 }
 935
 936                 f2fs_bug_on(F2FS_I_SB(inode),
 937                         !compr && ret != cluster_size &&
 938                         !is_inode_flag_set(inode, FI_COMPRESS_RELEASED));
 939         }
 940 fail:
 941         f2fs_put_dnode(&dn);
 942         return ret;
 943 }
 944
 945 /* return # of compressed blocks in compressed cluster */
 946 static int f2fs_compressed_blocks(struct compress_ctx *cc)
 947 {
 948         return __f2fs_cluster_blocks(cc->inode, cc->cluster_idx, true);
 949 }
 950
 951 /* return # of valid blocks in compressed cluster */
 952 int f2fs_is_compressed_cluster(struct inode *inode, pgoff_t index)
 953 {
 954         return __f2fs_cluster_blocks(inode,
 955                 index >> F2FS_I(inode)->i_log_cluster_size,
 956                 false);
 957 }
 958
 959 static bool cluster_may_compress(struct compress_ctx *cc)
 960 {
 961         if (!f2fs_need_compress_data(cc->inode))
 962                 return false;
 963         if (f2fs_is_atomic_file(cc->inode))
 964                 return false;
 965         if (!f2fs_cluster_is_full(cc))
 966                 return false;
 967         if (unlikely(f2fs_cp_error(F2FS_I_SB(cc->inode))))
 968                 return false;
 969         return !cluster_has_invalid_data(cc);
 970 }
 971
 972 static void set_cluster_writeback(struct compress_ctx *cc)
 973 {
 974         int i;
 975
 976         for (i = 0; i < cc->cluster_size; i++) {
 977                 if (cc->rpages[i])
 978                         set_page_writeback(cc->rpages[i]);
 979         }
 980 }
 981
 982 static void set_cluster_dirty(struct compress_ctx *cc)
 983 {
 984         int i;
 985
 986         for (i = 0; i < cc->cluster_size; i++)
 987                 if (cc->rpages[i])
 988                         set_page_dirty(cc->rpages[i]);
 989 }
 990
 991 static int prepare_compress_overwrite(struct compress_ctx *cc,
 992                 struct page **pagep, pgoff_t index, void **fsdata)
 993 {
 994         struct f2fs_sb_info *sbi = F2FS_I_SB(cc->inode);
 995         struct address_space *mapping = cc->inode->i_mapping;
 996         struct page *page;
 997         sector_t last_block_in_bio;
 998         unsigned fgp_flag = FGP_LOCK | FGP_WRITE | FGP_CREAT;
 999         pgoff_t start_idx = start_idx_of_cluster(cc);
1000         int i, ret;
1001
1002 retry:
1003         ret = f2fs_is_compressed_cluster(cc->inode, start_idx);
1004         if (ret <= 0)
1005                 return ret;
1006
1007         ret = f2fs_init_compress_ctx(cc);
1008         if (ret)
1009                 return ret;
1010
1011         /* keep page reference to avoid page reclaim */
1012         for (i = 0; i < cc->cluster_size; i++) {
1013                 page = f2fs_pagecache_get_page(mapping, start_idx + i,
1014                                                         fgp_flag, GFP_NOFS);
1015                 if (!page) {
1016                         ret = -ENOMEM;
1017                         goto unlock_pages;
1018                 }
1019
1020                 if (PageUptodate(page))
1021                         f2fs_put_page(page, 1);
1022                 else
1023                         f2fs_compress_ctx_add_page(cc, page);
1024         }
1025
1026         if (!f2fs_cluster_is_empty(cc)) {
1027                 struct bio *bio = NULL;
1028
1029                 ret = f2fs_read_multi_pages(cc, &bio, cc->cluster_size,
1030                                         &last_block_in_bio, false, true);
1031                 f2fs_put_rpages(cc);
1032                 f2fs_destroy_compress_ctx(cc, true);
1033                 if (ret)
1034                         goto out;
1035                 if (bio)
1036                         f2fs_submit_bio(sbi, bio, DATA);
1037
1038                 ret = f2fs_init_compress_ctx(cc);
1039                 if (ret)
1040                         goto out;
1041         }
1042
1043         for (i = 0; i < cc->cluster_size; i++) {
1044                 f2fs_bug_on(sbi, cc->rpages[i]);
1045
1046                 page = find_lock_page(mapping, start_idx + i);
1047                 if (!page) {
1048                         /* page can be truncated */
1049                         goto release_and_retry;
1050                 }
1051
1052                 f2fs_wait_on_page_writeback(page, DATA, true, true);
1053                 f2fs_compress_ctx_add_page(cc, page);
1054
1055                 if (!PageUptodate(page)) {
1056 release_and_retry:
1057                         f2fs_put_rpages(cc);
1058                         f2fs_unlock_rpages(cc, i + 1);
1059                         f2fs_destroy_compress_ctx(cc, true);
1060                         goto retry;
1061                 }
1062         }
1063
1064         if (likely(!ret)) {
1065                 *fsdata = cc->rpages;
1066                 *pagep = cc->rpages[offset_in_cluster(cc, index)];
1067                 return cc->cluster_size;
1068         }
1069
1070 unlock_pages:
1071         f2fs_put_rpages(cc);
1072         f2fs_unlock_rpages(cc, i);
1073         f2fs_destroy_compress_ctx(cc, true);
1074 out:
1075         return ret;
1076 }
1077
1078 int f2fs_prepare_compress_overwrite(struct inode *inode,
1079                 struct page **pagep, pgoff_t index, void **fsdata)
1080 {
1081         struct compress_ctx cc = {
1082                 .inode = inode,
1083                 .log_cluster_size = F2FS_I(inode)->i_log_cluster_size,
1084                 .cluster_size = F2FS_I(inode)->i_cluster_size,
1085                 .cluster_idx = index >> F2FS_I(inode)->i_log_cluster_size,
1086                 .rpages = NULL,
1087                 .nr_rpages = 0,
1088         };
1089
1090         return prepare_compress_overwrite(&cc, pagep, index, fsdata);
1091 }
1092
1093 bool f2fs_compress_write_end(struct inode *inode, void *fsdata,
1094                                         pgoff_t index, unsigned copied)
1095
1096 {
1097         struct compress_ctx cc = {
1098                 .inode = inode,
1099                 .log_cluster_size = F2FS_I(inode)->i_log_cluster_size,
1100                 .cluster_size = F2FS_I(inode)->i_cluster_size,
1101                 .rpages = fsdata,
1102         };
1103         bool first_index = (index == cc.rpages[0]->index);
1104
1105         if (copied)
1106                 set_cluster_dirty(&cc);
1107
1108         f2fs_put_rpages_wbc(&cc, NULL, false, 1);
1109         f2fs_destroy_compress_ctx(&cc, false);
1110
1111         return first_index;
1112 }
1113
1114 int f2fs_truncate_partial_cluster(struct inode *inode, u64 from, bool lock)
1115 {
1116         void *fsdata = NULL;
1117         struct page *pagep;
1118         int log_cluster_size = F2FS_I(inode)->i_log_cluster_size;
1119         pgoff_t start_idx = from >> (PAGE_SHIFT + log_cluster_size) <<
1120                                                         log_cluster_size;
1121         int err;
1122
1123         err = f2fs_is_compressed_cluster(inode, start_idx);
1124         if (err < 0)
1125                 return err;
1126
1127         /* truncate normal cluster */
1128         if (!err)
1129                 return f2fs_do_truncate_blocks(inode, from, lock);
1130
1131         /* truncate compressed cluster */
1132         err = f2fs_prepare_compress_overwrite(inode, &pagep,
1133                                                 start_idx, &fsdata);
1134
1135         /* should not be a normal cluster */
1136         f2fs_bug_on(F2FS_I_SB(inode), err == 0);
1137
1138         if (err <= 0)
1139                 return err;
1140
1141         if (err > 0) {
1142                 struct page **rpages = fsdata;
1143                 int cluster_size = F2FS_I(inode)->i_cluster_size;
1144                 int i;
1145
1146                 for (i = cluster_size - 1; i >= 0; i--) {
1147                         loff_t start = rpages[i]->index << PAGE_SHIFT;
1148
1149                         if (from <= start) {
1150                                 zero_user_segment(rpages[i], 0, PAGE_SIZE);
1151                         } else {
1152                                 zero_user_segment(rpages[i], from - start,
1153                                                                 PAGE_SIZE);
1154                                 break;
1155                         }
1156                 }
1157
1158                 f2fs_compress_write_end(inode, fsdata, start_idx, true);
1159         }
1160         return 0;
1161 }
1162
1163 static int f2fs_write_compressed_pages(struct compress_ctx *cc,
1164                                         int *submitted,
1165                                         struct writeback_control *wbc,
1166                                         enum iostat_type io_type)
1167 {
1168         struct inode *inode = cc->inode;
1169         struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
1170         struct f2fs_inode_info *fi = F2FS_I(inode);
1171         struct f2fs_io_info fio = {
1172                 .sbi = sbi,
1173                 .ino = cc->inode->i_ino,
1174                 .type = DATA,
1175                 .op = REQ_OP_WRITE,
1176                 .op_flags = wbc_to_write_flags(wbc),
1177                 .old_blkaddr = NEW_ADDR,
1178                 .page = NULL,
1179                 .encrypted_page = NULL,
1180                 .compressed_page = NULL,
1181                 .submitted = false,
1182                 .io_type = io_type,
1183                 .io_wbc = wbc,
1184                 .encrypted = fscrypt_inode_uses_fs_layer_crypto(cc->inode),
1185         };
1186         struct dnode_of_data dn;
1187         struct node_info ni;
1188         struct compress_io_ctx *cic;
1189         pgoff_t start_idx = start_idx_of_cluster(cc);
1190         unsigned int last_index = cc->cluster_size - 1;
1191         loff_t psize;
1192         int i, err;
1193
1194         /* we should bypass data pages to proceed the kworkder jobs */
1195         if (unlikely(f2fs_cp_error(sbi))) {
1196                 mapping_set_error(cc->rpages[0]->mapping, -EIO);
1197                 goto out_free;
1198         }
1199
1200         if (IS_NOQUOTA(inode)) {
1201                 /*
1202                  * We need to wait for node_write to avoid block allocation during
1203                  * checkpoint. This can only happen to quota writes which can cause
1204                  * the below discard race condition.
1205                  */
1206                 down_read(&sbi->node_write);
1207         } else if (!f2fs_trylock_op(sbi)) {
1208                 goto out_free;
1209         }
1210
1211         set_new_dnode(&dn, cc->inode, NULL, NULL, 0);
1212
1213         err = f2fs_get_dnode_of_data(&dn, start_idx, LOOKUP_NODE);
1214         if (err)
1215                 goto out_unlock_op;
1216
1217         for (i = 0; i < cc->cluster_size; i++) {
1218                 if (data_blkaddr(dn.inode, dn.node_page,
1219                                         dn.ofs_in_node + i) == NULL_ADDR)
1220                         goto out_put_dnode;
1221         }
1222
1223         psize = (loff_t)(cc->rpages[last_index]->index + 1) << PAGE_SHIFT;
1224
1225         err = f2fs_get_node_info(fio.sbi, dn.nid, &ni);
1226         if (err)
1227                 goto out_put_dnode;
1228
1229         fio.version = ni.version;
1230
1231         cic = kmem_cache_zalloc(cic_entry_slab, GFP_NOFS);
1232         if (!cic)
1233                 goto out_put_dnode;
1234
1235         cic->magic = F2FS_COMPRESSED_PAGE_MAGIC;
1236         cic->inode = inode;
1237         atomic_set(&cic->pending_pages, cc->nr_cpages);
1238         cic->rpages = page_array_alloc(cc->inode, cc->cluster_size);
1239         if (!cic->rpages)
1240                 goto out_put_cic;
1241
1242         cic->nr_rpages = cc->cluster_size;
1243
1244         for (i = 0; i < cc->nr_cpages; i++) {
1245                 f2fs_set_compressed_page(cc->cpages[i], inode,
1246                                         cc->rpages[i + 1]->index, cic);
1247                 fio.compressed_page = cc->cpages[i];
1248
1249                 fio.old_blkaddr = data_blkaddr(dn.inode, dn.node_page,
1250                                                 dn.ofs_in_node + i + 1);
1251
1252                 /* wait for GCed page writeback via META_MAPPING */
1253                 f2fs_wait_on_block_writeback(inode, fio.old_blkaddr);
1254
1255                 if (fio.encrypted) {
1256                         fio.page = cc->rpages[i + 1];
1257                         err = f2fs_encrypt_one_page(&fio);
1258                         if (err)
1259                                 goto out_destroy_crypt;
1260                         cc->cpages[i] = fio.encrypted_page;
1261                 }
1262         }
1263
1264         set_cluster_writeback(cc);
1265
1266         for (i = 0; i < cc->cluster_size; i++)
1267                 cic->rpages[i] = cc->rpages[i];
1268
1269         for (i = 0; i < cc->cluster_size; i++, dn.ofs_in_node++) {
1270                 block_t blkaddr;
1271
1272                 blkaddr = f2fs_data_blkaddr(&dn);
1273                 fio.page = cc->rpages[i];
1274                 fio.old_blkaddr = blkaddr;
1275
1276                 /* cluster header */
1277                 if (i == 0) {
1278                         if (blkaddr == COMPRESS_ADDR)
1279                                 fio.compr_blocks++;
1280                         if (__is_valid_data_blkaddr(blkaddr))
1281                                 f2fs_invalidate_blocks(sbi, blkaddr);
1282                         f2fs_update_data_blkaddr(&dn, COMPRESS_ADDR);
1283                         goto unlock_continue;
1284                 }
1285
1286                 if (fio.compr_blocks && __is_valid_data_blkaddr(blkaddr))
1287                         fio.compr_blocks++;
1288
1289                 if (i > cc->nr_cpages) {
1290                         if (__is_valid_data_blkaddr(blkaddr)) {
1291                                 f2fs_invalidate_blocks(sbi, blkaddr);
1292                                 f2fs_update_data_blkaddr(&dn, NEW_ADDR);
1293                         }
1294                         goto unlock_continue;
1295                 }
1296
1297                 f2fs_bug_on(fio.sbi, blkaddr == NULL_ADDR);
1298
1299                 if (fio.encrypted)
1300                         fio.encrypted_page = cc->cpages[i - 1];
1301                 else
1302                         fio.compressed_page = cc->cpages[i - 1];
1303
1304                 cc->cpages[i - 1] = NULL;
1305                 f2fs_outplace_write_data(&dn, &fio);
1306                 (*submitted)++;
1307 unlock_continue:
1308                 inode_dec_dirty_pages(cc->inode);
1309                 unlock_page(fio.page);
1310         }
1311
1312         if (fio.compr_blocks)
1313                 f2fs_i_compr_blocks_update(inode, fio.compr_blocks - 1, false);
1314         f2fs_i_compr_blocks_update(inode, cc->nr_cpages, true);
1315         add_compr_block_stat(inode, cc->nr_cpages);
1316
1317         set_inode_flag(cc->inode, FI_APPEND_WRITE);
1318         if (cc->cluster_idx == 0)
1319                 set_inode_flag(inode, FI_FIRST_BLOCK_WRITTEN);
1320
1321         f2fs_put_dnode(&dn);
1322         if (IS_NOQUOTA(inode))
1323                 up_read(&sbi->node_write);
1324         else
1325                 f2fs_unlock_op(sbi);
1326
1327         spin_lock(&fi->i_size_lock);
1328         if (fi->last_disk_size < psize)
1329                 fi->last_disk_size = psize;
1330         spin_unlock(&fi->i_size_lock);
1331
1332         f2fs_put_rpages(cc);
1333         page_array_free(cc->inode, cc->cpages, cc->nr_cpages);
1334         cc->cpages = NULL;
1335         f2fs_destroy_compress_ctx(cc, false);
1336         return 0;
1337
1338 out_destroy_crypt:
1339         page_array_free(cc->inode, cic->rpages, cc->cluster_size);
1340
1341         for (--i; i >= 0; i--)
1342                 fscrypt_finalize_bounce_page(&cc->cpages[i]);
1343         for (i = 0; i < cc->nr_cpages; i++) {
1344                 if (!cc->cpages[i])
1345                         continue;
1346                 f2fs_compress_free_page(cc->cpages[i]);
1347                 cc->cpages[i] = NULL;
1348         }
1349 out_put_cic:
1350         kmem_cache_free(cic_entry_slab, cic);
1351 out_put_dnode:
1352         f2fs_put_dnode(&dn);
1353 out_unlock_op:
1354         if (IS_NOQUOTA(inode))
1355                 up_read(&sbi->node_write);
1356         else
1357                 f2fs_unlock_op(sbi);
1358 out_free:
1359         page_array_free(cc->inode, cc->cpages, cc->nr_cpages);
1360         cc->cpages = NULL;
1361         return -EAGAIN;
1362 }
1363
1364 void f2fs_compress_write_end_io(struct bio *bio, struct page *page)
1365 {
1366         struct f2fs_sb_info *sbi = bio->bi_private;
1367         struct compress_io_ctx *cic =
1368                         (struct compress_io_ctx *)page_private(page);
1369         int i;
1370
1371         if (unlikely(bio->bi_status))
1372                 mapping_set_error(cic->inode->i_mapping, -EIO);
1373
1374         f2fs_compress_free_page(page);
1375
1376         dec_page_count(sbi, F2FS_WB_DATA);
1377
1378         if (atomic_dec_return(&cic->pending_pages))
1379                 return;
1380
1381         for (i = 0; i < cic->nr_rpages; i++) {
1382                 WARN_ON(!cic->rpages[i]);
1383                 clear_page_private_gcing(cic->rpages[i]);
1384                 end_page_writeback(cic->rpages[i]);
1385         }
1386
1387         page_array_free(cic->inode, cic->rpages, cic->nr_rpages);
1388         kmem_cache_free(cic_entry_slab, cic);
1389 }
1390
1391 static int f2fs_write_raw_pages(struct compress_ctx *cc,
1392                                         int *submitted,
1393                                         struct writeback_control *wbc,
1394                                         enum iostat_type io_type)
1395 {
1396         struct address_space *mapping = cc->inode->i_mapping;
1397         int _submitted, compr_blocks, ret;
1398         int i = -1, err = 0;
1399
1400         compr_blocks = f2fs_compressed_blocks(cc);
1401         if (compr_blocks < 0) {
1402                 err = compr_blocks;
1403                 goto out_err;
1404         }
1405
1406         for (i = 0; i < cc->cluster_size; i++) {
1407                 if (!cc->rpages[i])
1408                         continue;
1409 retry_write:
1410                 if (cc->rpages[i]->mapping != mapping) {
1411                         unlock_page(cc->rpages[i]);
1412                         continue;
1413                 }
1414
1415                 BUG_ON(!PageLocked(cc->rpages[i]));
1416
1417                 ret = f2fs_write_single_data_page(cc->rpages[i], &_submitted,
1418                                                 NULL, NULL, wbc, io_type,
1419                                                 compr_blocks, false);
1420                 if (ret) {
1421                         if (ret == AOP_WRITEPAGE_ACTIVATE) {
1422                                 unlock_page(cc->rpages[i]);
1423                                 ret = 0;
1424                         } else if (ret == -EAGAIN) {
1425                                 /*
1426                                  * for quota file, just redirty left pages to
1427                                  * avoid deadlock caused by cluster update race
1428                                  * from foreground operation.
1429                                  */
1430                                 if (IS_NOQUOTA(cc->inode)) {
1431                                         err = 0;
1432                                         goto out_err;
1433                                 }
1434                                 ret = 0;
1435                                 cond_resched();
1436                                 congestion_wait(BLK_RW_ASYNC,
1437                                                 DEFAULT_IO_TIMEOUT);
1438                                 lock_page(cc->rpages[i]);
1439
1440                                 if (!PageDirty(cc->rpages[i])) {
1441                                         unlock_page(cc->rpages[i]);
1442                                         continue;
1443                                 }
1444
1445                                 clear_page_dirty_for_io(cc->rpages[i]);
1446                                 goto retry_write;
1447                         }
1448                         err = ret;
1449                         goto out_err;
1450                 }
1451
1452                 *submitted += _submitted;
1453         }
1454
1455         f2fs_balance_fs(F2FS_M_SB(mapping), true);
1456
1457         return 0;
1458 out_err:
1459         for (++i; i < cc->cluster_size; i++) {
1460                 if (!cc->rpages[i])
1461                         continue;
1462                 redirty_page_for_writepage(wbc, cc->rpages[i]);
1463                 unlock_page(cc->rpages[i]);
1464         }
1465         return err;
1466 }
1467
1468 int f2fs_write_multi_pages(struct compress_ctx *cc,
1469                                         int *submitted,
1470                                         struct writeback_control *wbc,
1471                                         enum iostat_type io_type)
1472 {
1473         int err;
1474
1475         *submitted = 0;
1476         if (cluster_may_compress(cc)) {
1477                 err = f2fs_compress_pages(cc);
1478                 if (err == -EAGAIN) {
1479                         goto write;
1480                 } else if (err) {
1481                         f2fs_put_rpages_wbc(cc, wbc, true, 1);
1482                         goto destroy_out;
1483                 }
1484
1485                 err = f2fs_write_compressed_pages(cc, submitted,
1486                                                         wbc, io_type);
1487                 if (!err)
1488                         return 0;
1489                 f2fs_bug_on(F2FS_I_SB(cc->inode), err != -EAGAIN);
1490         }
1491 write:
1492         f2fs_bug_on(F2FS_I_SB(cc->inode), *submitted);
1493
1494         err = f2fs_write_raw_pages(cc, submitted, wbc, io_type);
1495         f2fs_put_rpages_wbc(cc, wbc, false, 0);
1496 destroy_out:
1497         f2fs_destroy_compress_ctx(cc, false);
1498         return err;
1499 }
1500
1501 static void f2fs_free_dic(struct decompress_io_ctx *dic);
1502
1503 struct decompress_io_ctx *f2fs_alloc_dic(struct compress_ctx *cc)
1504 {
1505         struct decompress_io_ctx *dic;
1506         pgoff_t start_idx = start_idx_of_cluster(cc);
1507         int i;
1508
1509         dic = kmem_cache_zalloc(dic_entry_slab, GFP_NOFS);
1510         if (!dic)
1511                 return ERR_PTR(-ENOMEM);
1512
1513         dic->rpages = page_array_alloc(cc->inode, cc->cluster_size);
1514         if (!dic->rpages) {
1515                 kmem_cache_free(dic_entry_slab, dic);
1516                 return ERR_PTR(-ENOMEM);
1517         }
1518
1519         dic->magic = F2FS_COMPRESSED_PAGE_MAGIC;
1520         dic->inode = cc->inode;
1521         atomic_set(&dic->remaining_pages, cc->nr_cpages);
1522         dic->cluster_idx = cc->cluster_idx;
1523         dic->cluster_size = cc->cluster_size;
1524         dic->log_cluster_size = cc->log_cluster_size;
1525         dic->nr_cpages = cc->nr_cpages;
1526         refcount_set(&dic->refcnt, 1);
1527         dic->failed = false;
1528         dic->need_verity = f2fs_need_verity(cc->inode, start_idx);
1529
1530         for (i = 0; i < dic->cluster_size; i++)
1531                 dic->rpages[i] = cc->rpages[i];
1532         dic->nr_rpages = cc->cluster_size;
1533
1534         dic->cpages = page_array_alloc(dic->inode, dic->nr_cpages);
1535         if (!dic->cpages)
1536                 goto out_free;
1537
1538         for (i = 0; i < dic->nr_cpages; i++) {
1539                 struct page *page;
1540
1541                 page = f2fs_compress_alloc_page();
1542                 if (!page)
1543                         goto out_free;
1544
1545                 f2fs_set_compressed_page(page, cc->inode,
1546                                         start_idx + i + 1, dic);
1547                 dic->cpages[i] = page;
1548         }
1549
1550         return dic;
1551
1552 out_free:
1553         f2fs_free_dic(dic);
1554         return ERR_PTR(-ENOMEM);
1555 }
1556
1557 static void f2fs_free_dic(struct decompress_io_ctx *dic)
1558 {
1559         int i;
1560
1561         if (dic->tpages) {
1562                 for (i = 0; i < dic->cluster_size; i++) {
1563                         if (dic->rpages[i])
1564                                 continue;
1565                         if (!dic->tpages[i])
1566                                 continue;
1567                         f2fs_compress_free_page(dic->tpages[i]);
1568                 }
1569                 page_array_free(dic->inode, dic->tpages, dic->cluster_size);
1570         }
1571
1572         if (dic->cpages) {
1573                 for (i = 0; i < dic->nr_cpages; i++) {
1574                         if (!dic->cpages[i])
1575                                 continue;
1576                         f2fs_compress_free_page(dic->cpages[i]);
1577                 }
1578                 page_array_free(dic->inode, dic->cpages, dic->nr_cpages);
1579         }
1580
1581         page_array_free(dic->inode, dic->rpages, dic->nr_rpages);
1582         kmem_cache_free(dic_entry_slab, dic);
1583 }
1584
1585 static void f2fs_put_dic(struct decompress_io_ctx *dic)
1586 {
1587         if (refcount_dec_and_test(&dic->refcnt))
1588                 f2fs_free_dic(dic);
1589 }
1590
1591 /*
1592  * Update and unlock the cluster's pagecache pages, and release the reference to
1593  * the decompress_io_ctx that was being held for I/O completion.
1594  */
1595 static void __f2fs_decompress_end_io(struct decompress_io_ctx *dic, bool failed)
1596 {
1597         int i;
1598
1599         for (i = 0; i < dic->cluster_size; i++) {
1600                 struct page *rpage = dic->rpages[i];
1601
1602                 if (!rpage)
1603                         continue;
1604
1605                 /* PG_error was set if verity failed. */
1606                 if (failed || PageError(rpage)) {
1607                         ClearPageUptodate(rpage);
1608                         /* will re-read again later */
1609                         ClearPageError(rpage);
1610                 } else {
1611                         SetPageUptodate(rpage);
1612                 }
1613                 unlock_page(rpage);
1614         }
1615
1616         f2fs_put_dic(dic);
1617 }
1618
1619 static void f2fs_verify_cluster(struct work_struct *work)
1620 {
1621         struct decompress_io_ctx *dic =
1622                 container_of(work, struct decompress_io_ctx, verity_work);
1623         int i;
1624
1625         /* Verify the cluster's decompressed pages with fs-verity. */
1626         for (i = 0; i < dic->cluster_size; i++) {
1627                 struct page *rpage = dic->rpages[i];
1628
1629                 if (rpage && !fsverity_verify_page(rpage))
1630                         SetPageError(rpage);
1631         }
1632
1633         __f2fs_decompress_end_io(dic, false);
1634 }
1635
1636 /*
1637  * This is called when a compressed cluster has been decompressed
1638  * (or failed to be read and/or decompressed).
1639  */
1640 void f2fs_decompress_end_io(struct decompress_io_ctx *dic, bool failed)
1641 {
1642         if (!failed && dic->need_verity) {
1643                 /*
1644                  * Note that to avoid deadlocks, the verity work can't be done
1645                  * on the decompression workqueue.  This is because verifying
1646                  * the data pages can involve reading metadata pages from the
1647                  * file, and these metadata pages may be compressed.
1648                  */
1649                 INIT_WORK(&dic->verity_work, f2fs_verify_cluster);
1650                 fsverity_enqueue_verify_work(&dic->verity_work);
1651         } else {
1652                 __f2fs_decompress_end_io(dic, failed);
1653         }
1654 }
1655
1656 /*
1657  * Put a reference to a compressed page's decompress_io_ctx.
1658  *
1659  * This is called when the page is no longer needed and can be freed.
1660  */
1661 void f2fs_put_page_dic(struct page *page)
1662 {
1663         struct decompress_io_ctx *dic =
1664                         (struct decompress_io_ctx *)page_private(page);
1665
1666         f2fs_put_dic(dic);
1667 }
1668
1669 const struct address_space_operations f2fs_compress_aops = {
1670         .releasepage = f2fs_release_page,
1671         .invalidatepage = f2fs_invalidate_page,
1672 };
1673
1674 struct address_space *COMPRESS_MAPPING(struct f2fs_sb_info *sbi)
1675 {
1676         return sbi->compress_inode->i_mapping;
1677 }
1678
1679 void f2fs_invalidate_compress_page(struct f2fs_sb_info *sbi, block_t blkaddr)
1680 {
1681         if (!sbi->compress_inode)
1682                 return;
1683         invalidate_mapping_pages(COMPRESS_MAPPING(sbi), blkaddr, blkaddr);
1684 }
1685
1686 void f2fs_cache_compressed_page(struct f2fs_sb_info *sbi, struct page *page,
1687                                                 nid_t ino, block_t blkaddr)
1688 {
1689         struct page *cpage;
1690         int ret;
1691
1692         if (!test_opt(sbi, COMPRESS_CACHE))
1693                 return;
1694
1695         if (!f2fs_is_valid_blkaddr(sbi, blkaddr, DATA_GENERIC_ENHANCE_READ))
1696                 return;
1697
1698         if (!f2fs_available_free_memory(sbi, COMPRESS_PAGE))
1699                 return;
1700
1701         cpage = find_get_page(COMPRESS_MAPPING(sbi), blkaddr);
1702         if (cpage) {
1703                 f2fs_put_page(cpage, 0);
1704                 return;
1705         }
1706
1707         cpage = alloc_page(__GFP_NOWARN | __GFP_IO);
1708         if (!cpage)
1709                 return;
1710
1711         ret = add_to_page_cache_lru(cpage, COMPRESS_MAPPING(sbi),
1712                                                 blkaddr, GFP_NOFS);
1713         if (ret) {
1714                 f2fs_put_page(cpage, 0);
1715                 return;
1716         }
1717
1718         set_page_private_data(cpage, ino);
1719
1720         if (!f2fs_is_valid_blkaddr(sbi, blkaddr, DATA_GENERIC_ENHANCE_READ))
1721                 goto out;
1722
1723         memcpy(page_address(cpage), page_address(page), PAGE_SIZE);
1724         SetPageUptodate(cpage);
1725 out:
1726         f2fs_put_page(cpage, 1);
1727 }
1728
1729 bool f2fs_load_compressed_page(struct f2fs_sb_info *sbi, struct page *page,
1730                                                                 block_t blkaddr)
1731 {
1732         struct page *cpage;
1733         bool hitted = false;
1734
1735         if (!test_opt(sbi, COMPRESS_CACHE))
1736                 return false;
1737
1738         cpage = f2fs_pagecache_get_page(COMPRESS_MAPPING(sbi),
1739                                 blkaddr, FGP_LOCK | FGP_NOWAIT, GFP_NOFS);
1740         if (cpage) {
1741                 if (PageUptodate(cpage)) {
1742                         atomic_inc(&sbi->compress_page_hit);
1743                         memcpy(page_address(page),
1744                                 page_address(cpage), PAGE_SIZE);
1745                         hitted = true;
1746                 }
1747                 f2fs_put_page(cpage, 1);
1748         }
1749
1750         return hitted;
1751 }
1752
1753 void f2fs_invalidate_compress_pages(struct f2fs_sb_info *sbi, nid_t ino)
1754 {
1755         struct address_space *mapping = sbi->compress_inode->i_mapping;
1756         struct pagevec pvec;
1757         pgoff_t index = 0;
1758         pgoff_t end = MAX_BLKADDR(sbi);
1759
1760         if (!mapping->nrpages)
1761                 return;
1762
1763         pagevec_init(&pvec);
1764
1765         do {
1766                 unsigned int nr_pages;
1767                 int i;
1768
1769                 nr_pages = pagevec_lookup_range(&pvec, mapping,
1770                                                 &index, end - 1);
1771                 if (!nr_pages)
1772                         break;
1773
1774                 for (i = 0; i < nr_pages; i++) {
1775                         struct page *page = pvec.pages[i];
1776
1777                         if (page->index > end)
1778                                 break;
1779
1780                         lock_page(page);
1781                         if (page->mapping != mapping) {
1782                                 unlock_page(page);
1783                                 continue;
1784                         }
1785
1786                         if (ino != get_page_private_data(page)) {
1787                                 unlock_page(page);
1788                                 continue;
1789                         }
1790
1791                         generic_error_remove_page(mapping, page);
1792                         unlock_page(page);
1793                 }
1794                 pagevec_release(&pvec);
1795                 cond_resched();
1796         } while (index < end);
1797 }
1798
1799 int f2fs_init_compress_inode(struct f2fs_sb_info *sbi)
1800 {
1801         struct inode *inode;
1802
1803         if (!test_opt(sbi, COMPRESS_CACHE))
1804                 return 0;
1805
1806         inode = f2fs_iget(sbi->sb, F2FS_COMPRESS_INO(sbi));
1807         if (IS_ERR(inode))
1808                 return PTR_ERR(inode);
1809         sbi->compress_inode = inode;
1810
1811         sbi->compress_percent = COMPRESS_PERCENT;
1812         sbi->compress_watermark = COMPRESS_WATERMARK;
1813
1814         atomic_set(&sbi->compress_page_hit, 0);
1815
1816         return 0;
1817 }
1818
1819 void f2fs_destroy_compress_inode(struct f2fs_sb_info *sbi)
1820 {
1821         if (!sbi->compress_inode)
1822                 return;
1823         iput(sbi->compress_inode);
1824         sbi->compress_inode = NULL;
1825 }
1826
1827 int f2fs_init_page_array_cache(struct f2fs_sb_info *sbi)
1828 {
1829         dev_t dev = sbi->sb->s_bdev->bd_dev;
1830         char slab_name[32];
1831
1832         sprintf(slab_name, "f2fs_page_array_entry-%u:%u", MAJOR(dev), MINOR(dev));
1833
1834         sbi->page_array_slab_size = sizeof(struct page *) <<
1835                                         F2FS_OPTION(sbi).compress_log_size;
1836
1837         sbi->page_array_slab = f2fs_kmem_cache_create(slab_name,
1838                                         sbi->page_array_slab_size);
1839         if (!sbi->page_array_slab)
1840                 return -ENOMEM;
1841         return 0;
1842 }
1843
1844 void f2fs_destroy_page_array_cache(struct f2fs_sb_info *sbi)
1845 {
1846         kmem_cache_destroy(sbi->page_array_slab);
1847 }
1848
1849 static int __init f2fs_init_cic_cache(void)
1850 {
1851         cic_entry_slab = f2fs_kmem_cache_create("f2fs_cic_entry",
1852                                         sizeof(struct compress_io_ctx));
1853         if (!cic_entry_slab)
1854                 return -ENOMEM;
1855         return 0;
1856 }
1857
1858 static void f2fs_destroy_cic_cache(void)
1859 {
1860         kmem_cache_destroy(cic_entry_slab);
1861 }
1862
1863 static int __init f2fs_init_dic_cache(void)
1864 {
1865         dic_entry_slab = f2fs_kmem_cache_create("f2fs_dic_entry",
1866                                         sizeof(struct decompress_io_ctx));
1867         if (!dic_entry_slab)
1868                 return -ENOMEM;
1869         return 0;
1870 }
1871
1872 static void f2fs_destroy_dic_cache(void)
1873 {
1874         kmem_cache_destroy(dic_entry_slab);
1875 }
1876
1877 int __init f2fs_init_compress_cache(void)
1878 {
1879         int err;
1880
1881         err = f2fs_init_cic_cache();
1882         if (err)
1883                 goto out;
1884         err = f2fs_init_dic_cache();
1885         if (err)
1886                 goto free_cic;
1887         return 0;
1888 free_cic:
1889         f2fs_destroy_cic_cache();
1890 out:
1891         return -ENOMEM;
1892 }
1893
1894 void f2fs_destroy_compress_cache(void)
1895 {
1896         f2fs_destroy_dic_cache();
1897         f2fs_destroy_cic_cache();
1898 }