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
  16 #include "f2fs.h"
  17 #include "node.h"
  18 #include <trace/events/f2fs.h>
  19
  20 static struct kmem_cache *cic_entry_slab;
  21 static struct kmem_cache *dic_entry_slab;
  22
  23 static void *page_array_alloc(struct inode *inode, int nr)
  24 {
  25         struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
  26         unsigned int size = sizeof(struct page *) * nr;
  27
  28         if (likely(size <= sbi->page_array_slab_size))
  29                 return kmem_cache_zalloc(sbi->page_array_slab, GFP_NOFS);
  30         return f2fs_kzalloc(sbi, size, GFP_NOFS);
  31 }
  32
  33 static void page_array_free(struct inode *inode, void *pages, int nr)
  34 {
  35         struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
  36         unsigned int size = sizeof(struct page *) * nr;
  37
  38         if (!pages)
  39                 return;
  40
  41         if (likely(size <= sbi->page_array_slab_size))
  42                 kmem_cache_free(sbi->page_array_slab, pages);
  43         else
  44                 kfree(pages);
  45 }
  46
  47 struct f2fs_compress_ops {
  48         int (*init_compress_ctx)(struct compress_ctx *cc);
  49         void (*destroy_compress_ctx)(struct compress_ctx *cc);
  50         int (*compress_pages)(struct compress_ctx *cc);
  51         int (*init_decompress_ctx)(struct decompress_io_ctx *dic);
  52         void (*destroy_decompress_ctx)(struct decompress_io_ctx *dic);
  53         int (*decompress_pages)(struct decompress_io_ctx *dic);
  54 };
  55
  56 static unsigned int offset_in_cluster(struct compress_ctx *cc, pgoff_t index)
  57 {
  58         return index & (cc->cluster_size - 1);
  59 }
  60
  61 static pgoff_t cluster_idx(struct compress_ctx *cc, pgoff_t index)
  62 {
  63         return index >> cc->log_cluster_size;
  64 }
  65
  66 static pgoff_t start_idx_of_cluster(struct compress_ctx *cc)
  67 {
  68         return cc->cluster_idx << cc->log_cluster_size;
  69 }
  70
  71 bool f2fs_is_compressed_page(struct page *page)
  72 {
  73         if (!PagePrivate(page))
  74                 return false;
  75         if (!page_private(page))
  76                 return false;
  77         if (IS_ATOMIC_WRITTEN_PAGE(page) || IS_DUMMY_WRITTEN_PAGE(page))
  78                 return false;
  79
  80         f2fs_bug_on(F2FS_M_SB(page->mapping),
  81                 *((u32 *)page_private(page)) != F2FS_COMPRESSED_PAGE_MAGIC);
  82         return true;
  83 }
  84
  85 static void f2fs_set_compressed_page(struct page *page,
  86                 struct inode *inode, pgoff_t index, void *data)
  87 {
  88         SetPagePrivate(page);
  89         set_page_private(page, (unsigned long)data);
  90
  91         /* i_crypto_info and iv index */
  92         page->index = index;
  93         page->mapping = inode->i_mapping;
  94 }
  95
  96 static void f2fs_drop_rpages(struct compress_ctx *cc, int len, bool unlock)
  97 {
  98         int i;
  99
 100         for (i = 0; i < len; i++) {
 101                 if (!cc->rpages[i])
 102                         continue;
 103                 if (unlock)
 104                         unlock_page(cc->rpages[i]);
 105                 else
 106                         put_page(cc->rpages[i]);
 107         }
 108 }
 109
 110 static void f2fs_put_rpages(struct compress_ctx *cc)
 111 {
 112         f2fs_drop_rpages(cc, cc->cluster_size, false);
 113 }
 114
 115 static void f2fs_unlock_rpages(struct compress_ctx *cc, int len)
 116 {
 117         f2fs_drop_rpages(cc, len, true);
 118 }
 119
 120 static void f2fs_put_rpages_wbc(struct compress_ctx *cc,
 121                 struct writeback_control *wbc, bool redirty, int unlock)
 122 {
 123         unsigned int i;
 124
 125         for (i = 0; i < cc->cluster_size; i++) {
 126                 if (!cc->rpages[i])
 127                         continue;
 128                 if (redirty)
 129                         redirty_page_for_writepage(wbc, cc->rpages[i]);
 130                 f2fs_put_page(cc->rpages[i], unlock);
 131         }
 132 }
 133
 134 struct page *f2fs_compress_control_page(struct page *page)
 135 {
 136         return ((struct compress_io_ctx *)page_private(page))->rpages[0];
 137 }
 138
 139 int f2fs_init_compress_ctx(struct compress_ctx *cc)
 140 {
 141         if (cc->rpages)
 142                 return 0;
 143
 144         cc->rpages = page_array_alloc(cc->inode, cc->cluster_size);
 145         return cc->rpages ? 0 : -ENOMEM;
 146 }
 147
 148 void f2fs_destroy_compress_ctx(struct compress_ctx *cc, bool reuse)
 149 {
 150         page_array_free(cc->inode, cc->rpages, cc->cluster_size);
 151         cc->rpages = NULL;
 152         cc->nr_rpages = 0;
 153         cc->nr_cpages = 0;
 154         if (!reuse)
 155                 cc->cluster_idx = NULL_CLUSTER;
 156 }
 157
 158 void f2fs_compress_ctx_add_page(struct compress_ctx *cc, struct page *page)
 159 {
 160         unsigned int cluster_ofs;
 161
 162         if (!f2fs_cluster_can_merge_page(cc, page->index))
 163                 f2fs_bug_on(F2FS_I_SB(cc->inode), 1);
 164
 165         cluster_ofs = offset_in_cluster(cc, page->index);
 166         cc->rpages[cluster_ofs] = page;
 167         cc->nr_rpages++;
 168         cc->cluster_idx = cluster_idx(cc, page->index);
 169 }
 170
 171 #ifdef CONFIG_F2FS_FS_LZO
 172 static int lzo_init_compress_ctx(struct compress_ctx *cc)
 173 {
 174         cc->private = f2fs_kvmalloc(F2FS_I_SB(cc->inode),
 175                                 LZO1X_MEM_COMPRESS, GFP_NOFS);
 176         if (!cc->private)
 177                 return -ENOMEM;
 178
 179         cc->clen = lzo1x_worst_compress(PAGE_SIZE << cc->log_cluster_size);
 180         return 0;
 181 }
 182
 183 static void lzo_destroy_compress_ctx(struct compress_ctx *cc)
 184 {
 185         kvfree(cc->private);
 186         cc->private = NULL;
 187 }
 188
 189 static int lzo_compress_pages(struct compress_ctx *cc)
 190 {
 191         int ret;
 192
 193         ret = lzo1x_1_compress(cc->rbuf, cc->rlen, cc->cbuf->cdata,
 194                                         &cc->clen, cc->private);
 195         if (ret != LZO_E_OK) {
 196                 printk_ratelimited("%sF2FS-fs (%s): lzo compress failed, ret:%d\n",
 197                                 KERN_ERR, F2FS_I_SB(cc->inode)->sb->s_id, ret);
 198                 return -EIO;
 199         }
 200         return 0;
 201 }
 202
 203 static int lzo_decompress_pages(struct decompress_io_ctx *dic)
 204 {
 205         int ret;
 206
 207         ret = lzo1x_decompress_safe(dic->cbuf->cdata, dic->clen,
 208                                                 dic->rbuf, &dic->rlen);
 209         if (ret != LZO_E_OK) {
 210                 printk_ratelimited("%sF2FS-fs (%s): lzo decompress failed, ret:%d\n",
 211                                 KERN_ERR, F2FS_I_SB(dic->inode)->sb->s_id, ret);
 212                 return -EIO;
 213         }
 214
 215         if (dic->rlen != PAGE_SIZE << dic->log_cluster_size) {
 216                 printk_ratelimited("%sF2FS-fs (%s): lzo invalid rlen:%zu, "
 217                                         "expected:%lu\n", KERN_ERR,
 218                                         F2FS_I_SB(dic->inode)->sb->s_id,
 219                                         dic->rlen,
 220                                         PAGE_SIZE << dic->log_cluster_size);
 221                 return -EIO;
 222         }
 223         return 0;
 224 }
 225
 226 static const struct f2fs_compress_ops f2fs_lzo_ops = {
 227         .init_compress_ctx      = lzo_init_compress_ctx,
 228         .destroy_compress_ctx   = lzo_destroy_compress_ctx,
 229         .compress_pages         = lzo_compress_pages,
 230         .decompress_pages       = lzo_decompress_pages,
 231 };
 232 #endif
 233
 234 #ifdef CONFIG_F2FS_FS_LZ4
 235 static int lz4_init_compress_ctx(struct compress_ctx *cc)
 236 {
 237         unsigned int size = LZ4_MEM_COMPRESS;
 238
 239 #ifdef CONFIG_F2FS_FS_LZ4HC
 240         if (F2FS_I(cc->inode)->i_compress_flag >> COMPRESS_LEVEL_OFFSET)
 241                 size = LZ4HC_MEM_COMPRESS;
 242 #endif
 243
 244         cc->private = f2fs_kvmalloc(F2FS_I_SB(cc->inode), size, GFP_NOFS);
 245         if (!cc->private)
 246                 return -ENOMEM;
 247
 248         /*
 249          * we do not change cc->clen to LZ4_compressBound(inputsize) to
 250          * adapt worst compress case, because lz4 compressor can handle
 251          * output budget properly.
 252          */
 253         cc->clen = cc->rlen - PAGE_SIZE - COMPRESS_HEADER_SIZE;
 254         return 0;
 255 }
 256
 257 static void lz4_destroy_compress_ctx(struct compress_ctx *cc)
 258 {
 259         kvfree(cc->private);
 260         cc->private = NULL;
 261 }
 262
 263 #ifdef CONFIG_F2FS_FS_LZ4HC
 264 static int lz4hc_compress_pages(struct compress_ctx *cc)
 265 {
 266         unsigned char level = F2FS_I(cc->inode)->i_compress_flag >>
 267                                                 COMPRESS_LEVEL_OFFSET;
 268         int len;
 269
 270         if (level)
 271                 len = LZ4_compress_HC(cc->rbuf, cc->cbuf->cdata, cc->rlen,
 272                                         cc->clen, level, cc->private);
 273         else
 274                 len = LZ4_compress_default(cc->rbuf, cc->cbuf->cdata, cc->rlen,
 275                                                 cc->clen, cc->private);
 276         if (!len)
 277                 return -EAGAIN;
 278
 279         cc->clen = len;
 280         return 0;
 281 }
 282 #endif
 283
 284 static int lz4_compress_pages(struct compress_ctx *cc)
 285 {
 286         int len;
 287
 288 #ifdef CONFIG_F2FS_FS_LZ4HC
 289         return lz4hc_compress_pages(cc);
 290 #endif
 291         len = LZ4_compress_default(cc->rbuf, cc->cbuf->cdata, cc->rlen,
 292                                                 cc->clen, cc->private);
 293         if (!len)
 294                 return -EAGAIN;
 295
 296         cc->clen = len;
 297         return 0;
 298 }
 299
 300 static int lz4_decompress_pages(struct decompress_io_ctx *dic)
 301 {
 302         int ret;
 303
 304         ret = LZ4_decompress_safe(dic->cbuf->cdata, dic->rbuf,
 305                                                 dic->clen, dic->rlen);
 306         if (ret < 0) {
 307                 printk_ratelimited("%sF2FS-fs (%s): lz4 decompress failed, ret:%d\n",
 308                                 KERN_ERR, F2FS_I_SB(dic->inode)->sb->s_id, ret);
 309                 return -EIO;
 310         }
 311
 312         if (ret != PAGE_SIZE << dic->log_cluster_size) {
 313                 printk_ratelimited("%sF2FS-fs (%s): lz4 invalid rlen:%zu, "
 314                                         "expected:%lu\n", KERN_ERR,
 315                                         F2FS_I_SB(dic->inode)->sb->s_id,
 316                                         dic->rlen,
 317                                         PAGE_SIZE << dic->log_cluster_size);
 318                 return -EIO;
 319         }
 320         return 0;
 321 }
 322
 323 static const struct f2fs_compress_ops f2fs_lz4_ops = {
 324         .init_compress_ctx      = lz4_init_compress_ctx,
 325         .destroy_compress_ctx   = lz4_destroy_compress_ctx,
 326         .compress_pages         = lz4_compress_pages,
 327         .decompress_pages       = lz4_decompress_pages,
 328 };
 329 #endif
 330
 331 #ifdef CONFIG_F2FS_FS_ZSTD
 332 #define F2FS_ZSTD_DEFAULT_CLEVEL        1
 333
 334 static int zstd_init_compress_ctx(struct compress_ctx *cc)
 335 {
 336         ZSTD_parameters params;
 337         ZSTD_CStream *stream;
 338         void *workspace;
 339         unsigned int workspace_size;
 340         unsigned char level = F2FS_I(cc->inode)->i_compress_flag >>
 341                                                 COMPRESS_LEVEL_OFFSET;
 342
 343         if (!level)
 344                 level = F2FS_ZSTD_DEFAULT_CLEVEL;
 345
 346         params = ZSTD_getParams(level, cc->rlen, 0);
 347         workspace_size = ZSTD_CStreamWorkspaceBound(params.cParams);
 348
 349         workspace = f2fs_kvmalloc(F2FS_I_SB(cc->inode),
 350                                         workspace_size, GFP_NOFS);
 351         if (!workspace)
 352                 return -ENOMEM;
 353
 354         stream = ZSTD_initCStream(params, 0, workspace, workspace_size);
 355         if (!stream) {
 356                 printk_ratelimited("%sF2FS-fs (%s): %s ZSTD_initCStream failed\n",
 357                                 KERN_ERR, F2FS_I_SB(cc->inode)->sb->s_id,
 358                                 __func__);
 359                 kvfree(workspace);
 360                 return -EIO;
 361         }
 362
 363         cc->private = workspace;
 364         cc->private2 = stream;
 365
 366         cc->clen = cc->rlen - PAGE_SIZE - COMPRESS_HEADER_SIZE;
 367         return 0;
 368 }
 369
 370 static void zstd_destroy_compress_ctx(struct compress_ctx *cc)
 371 {
 372         kvfree(cc->private);
 373         cc->private = NULL;
 374         cc->private2 = NULL;
 375 }
 376
 377 static int zstd_compress_pages(struct compress_ctx *cc)
 378 {
 379         ZSTD_CStream *stream = cc->private2;
 380         ZSTD_inBuffer inbuf;
 381         ZSTD_outBuffer outbuf;
 382         int src_size = cc->rlen;
 383         int dst_size = src_size - PAGE_SIZE - COMPRESS_HEADER_SIZE;
 384         int ret;
 385
 386         inbuf.pos = 0;
 387         inbuf.src = cc->rbuf;
 388         inbuf.size = src_size;
 389
 390         outbuf.pos = 0;
 391         outbuf.dst = cc->cbuf->cdata;
 392         outbuf.size = dst_size;
 393
 394         ret = ZSTD_compressStream(stream, &outbuf, &inbuf);
 395         if (ZSTD_isError(ret)) {
 396                 printk_ratelimited("%sF2FS-fs (%s): %s ZSTD_compressStream failed, ret: %d\n",
 397                                 KERN_ERR, F2FS_I_SB(cc->inode)->sb->s_id,
 398                                 __func__, ZSTD_getErrorCode(ret));
 399                 return -EIO;
 400         }
 401
 402         ret = ZSTD_endStream(stream, &outbuf);
 403         if (ZSTD_isError(ret)) {
 404                 printk_ratelimited("%sF2FS-fs (%s): %s ZSTD_endStream returned %d\n",
 405                                 KERN_ERR, F2FS_I_SB(cc->inode)->sb->s_id,
 406                                 __func__, ZSTD_getErrorCode(ret));
 407                 return -EIO;
 408         }
 409
 410         /*
 411          * there is compressed data remained in intermediate buffer due to
 412          * no more space in cbuf.cdata
 413          */
 414         if (ret)
 415                 return -EAGAIN;
 416
 417         cc->clen = outbuf.pos;
 418         return 0;
 419 }
 420
 421 static int zstd_init_decompress_ctx(struct decompress_io_ctx *dic)
 422 {
 423         ZSTD_DStream *stream;
 424         void *workspace;
 425         unsigned int workspace_size;
 426         unsigned int max_window_size =
 427                         MAX_COMPRESS_WINDOW_SIZE(dic->log_cluster_size);
 428
 429         workspace_size = ZSTD_DStreamWorkspaceBound(max_window_size);
 430
 431         workspace = f2fs_kvmalloc(F2FS_I_SB(dic->inode),
 432                                         workspace_size, GFP_NOFS);
 433         if (!workspace)
 434                 return -ENOMEM;
 435
 436         stream = ZSTD_initDStream(max_window_size, workspace, workspace_size);
 437         if (!stream) {
 438                 printk_ratelimited("%sF2FS-fs (%s): %s ZSTD_initDStream failed\n",
 439                                 KERN_ERR, F2FS_I_SB(dic->inode)->sb->s_id,
 440                                 __func__);
 441                 kvfree(workspace);
 442                 return -EIO;
 443         }
 444
 445         dic->private = workspace;
 446         dic->private2 = stream;
 447
 448         return 0;
 449 }
 450
 451 static void zstd_destroy_decompress_ctx(struct decompress_io_ctx *dic)
 452 {
 453         kvfree(dic->private);
 454         dic->private = NULL;
 455         dic->private2 = NULL;
 456 }
 457
 458 static int zstd_decompress_pages(struct decompress_io_ctx *dic)
 459 {
 460         ZSTD_DStream *stream = dic->private2;
 461         ZSTD_inBuffer inbuf;
 462         ZSTD_outBuffer outbuf;
 463         int ret;
 464
 465         inbuf.pos = 0;
 466         inbuf.src = dic->cbuf->cdata;
 467         inbuf.size = dic->clen;
 468
 469         outbuf.pos = 0;
 470         outbuf.dst = dic->rbuf;
 471         outbuf.size = dic->rlen;
 472
 473         ret = ZSTD_decompressStream(stream, &outbuf, &inbuf);
 474         if (ZSTD_isError(ret)) {
 475                 printk_ratelimited("%sF2FS-fs (%s): %s ZSTD_compressStream failed, ret: %d\n",
 476                                 KERN_ERR, F2FS_I_SB(dic->inode)->sb->s_id,
 477                                 __func__, ZSTD_getErrorCode(ret));
 478                 return -EIO;
 479         }
 480
 481         if (dic->rlen != outbuf.pos) {
 482                 printk_ratelimited("%sF2FS-fs (%s): %s ZSTD invalid rlen:%zu, "
 483                                 "expected:%lu\n", KERN_ERR,
 484                                 F2FS_I_SB(dic->inode)->sb->s_id,
 485                                 __func__, dic->rlen,
 486                                 PAGE_SIZE << dic->log_cluster_size);
 487                 return -EIO;
 488         }
 489
 490         return 0;
 491 }
 492
 493 static const struct f2fs_compress_ops f2fs_zstd_ops = {
 494         .init_compress_ctx      = zstd_init_compress_ctx,
 495         .destroy_compress_ctx   = zstd_destroy_compress_ctx,
 496         .compress_pages         = zstd_compress_pages,
 497         .init_decompress_ctx    = zstd_init_decompress_ctx,
 498         .destroy_decompress_ctx = zstd_destroy_decompress_ctx,
 499         .decompress_pages       = zstd_decompress_pages,
 500 };
 501 #endif
 502
 503 #ifdef CONFIG_F2FS_FS_LZO
 504 #ifdef CONFIG_F2FS_FS_LZORLE
 505 static int lzorle_compress_pages(struct compress_ctx *cc)
 506 {
 507         int ret;
 508
 509         ret = lzorle1x_1_compress(cc->rbuf, cc->rlen, cc->cbuf->cdata,
 510                                         &cc->clen, cc->private);
 511         if (ret != LZO_E_OK) {
 512                 printk_ratelimited("%sF2FS-fs (%s): lzo-rle compress failed, ret:%d\n",
 513                                 KERN_ERR, F2FS_I_SB(cc->inode)->sb->s_id, ret);
 514                 return -EIO;
 515         }
 516         return 0;
 517 }
 518
 519 static const struct f2fs_compress_ops f2fs_lzorle_ops = {
 520         .init_compress_ctx      = lzo_init_compress_ctx,
 521         .destroy_compress_ctx   = lzo_destroy_compress_ctx,
 522         .compress_pages         = lzorle_compress_pages,
 523         .decompress_pages       = lzo_decompress_pages,
 524 };
 525 #endif
 526 #endif
 527
 528 static const struct f2fs_compress_ops *f2fs_cops[COMPRESS_MAX] = {
 529 #ifdef CONFIG_F2FS_FS_LZO
 530         &f2fs_lzo_ops,
 531 #else
 532         NULL,
 533 #endif
 534 #ifdef CONFIG_F2FS_FS_LZ4
 535         &f2fs_lz4_ops,
 536 #else
 537         NULL,
 538 #endif
 539 #ifdef CONFIG_F2FS_FS_ZSTD
 540         &f2fs_zstd_ops,
 541 #else
 542         NULL,
 543 #endif
 544 #if defined(CONFIG_F2FS_FS_LZO) && defined(CONFIG_F2FS_FS_LZORLE)
 545         &f2fs_lzorle_ops,
 546 #else
 547         NULL,
 548 #endif
 549 };
 550
 551 bool f2fs_is_compress_backend_ready(struct inode *inode)
 552 {
 553         if (!f2fs_compressed_file(inode))
 554                 return true;
 555         return f2fs_cops[F2FS_I(inode)->i_compress_algorithm];
 556 }
 557
 558 static mempool_t *compress_page_pool;
 559 static int num_compress_pages = 512;
 560 module_param(num_compress_pages, uint, 0444);
 561 MODULE_PARM_DESC(num_compress_pages,
 562                 "Number of intermediate compress pages to preallocate");
 563
 564 int f2fs_init_compress_mempool(void)
 565 {
 566         compress_page_pool = mempool_create_page_pool(num_compress_pages, 0);
 567         if (!compress_page_pool)
 568                 return -ENOMEM;
 569
 570         return 0;
 571 }
 572
 573 void f2fs_destroy_compress_mempool(void)
 574 {
 575         mempool_destroy(compress_page_pool);
 576 }
 577
 578 static struct page *f2fs_compress_alloc_page(void)
 579 {
 580         struct page *page;
 581
 582         page = mempool_alloc(compress_page_pool, GFP_NOFS);
 583         lock_page(page);
 584
 585         return page;
 586 }
 587
 588 static void f2fs_compress_free_page(struct page *page)
 589 {
 590         if (!page)
 591                 return;
 592         set_page_private(page, (unsigned long)NULL);
 593         ClearPagePrivate(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 static 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 {
 842         struct decompress_io_ctx *dic =
 843                         (struct decompress_io_ctx *)page_private(page);
 844         struct f2fs_sb_info *sbi = F2FS_I_SB(dic->inode);
 845
 846         dec_page_count(sbi, F2FS_RD_DATA);
 847
 848         if (failed)
 849                 WRITE_ONCE(dic->failed, true);
 850
 851         if (atomic_dec_and_test(&dic->remaining_pages))
 852                 f2fs_decompress_cluster(dic);
 853 }
 854
 855 static bool is_page_in_cluster(struct compress_ctx *cc, pgoff_t index)
 856 {
 857         if (cc->cluster_idx == NULL_CLUSTER)
 858                 return true;
 859         return cc->cluster_idx == cluster_idx(cc, index);
 860 }
 861
 862 bool f2fs_cluster_is_empty(struct compress_ctx *cc)
 863 {
 864         return cc->nr_rpages == 0;
 865 }
 866
 867 static bool f2fs_cluster_is_full(struct compress_ctx *cc)
 868 {
 869         return cc->cluster_size == cc->nr_rpages;
 870 }
 871
 872 bool f2fs_cluster_can_merge_page(struct compress_ctx *cc, pgoff_t index)
 873 {
 874         if (f2fs_cluster_is_empty(cc))
 875                 return true;
 876         return is_page_in_cluster(cc, index);
 877 }
 878
 879 static bool __cluster_may_compress(struct compress_ctx *cc)
 880 {
 881         loff_t i_size = i_size_read(cc->inode);
 882         unsigned nr_pages = DIV_ROUND_UP(i_size, PAGE_SIZE);
 883         int i;
 884
 885         for (i = 0; i < cc->cluster_size; i++) {
 886                 struct page *page = cc->rpages[i];
 887
 888                 f2fs_bug_on(F2FS_I_SB(cc->inode), !page);
 889
 890                 /* beyond EOF */
 891                 if (page->index >= nr_pages)
 892                         return false;
 893         }
 894         return true;
 895 }
 896
 897 static int __f2fs_cluster_blocks(struct compress_ctx *cc, bool compr)
 898 {
 899         struct dnode_of_data dn;
 900         int ret;
 901
 902         set_new_dnode(&dn, cc->inode, NULL, NULL, 0);
 903         ret = f2fs_get_dnode_of_data(&dn, start_idx_of_cluster(cc),
 904                                                         LOOKUP_NODE);
 905         if (ret) {
 906                 if (ret == -ENOENT)
 907                         ret = 0;
 908                 goto fail;
 909         }
 910
 911         if (dn.data_blkaddr == COMPRESS_ADDR) {
 912                 int i;
 913
 914                 ret = 1;
 915                 for (i = 1; i < cc->cluster_size; i++) {
 916                         block_t blkaddr;
 917
 918                         blkaddr = data_blkaddr(dn.inode,
 919                                         dn.node_page, dn.ofs_in_node + i);
 920                         if (compr) {
 921                                 if (__is_valid_data_blkaddr(blkaddr))
 922                                         ret++;
 923                         } else {
 924                                 if (blkaddr != NULL_ADDR)
 925                                         ret++;
 926                         }
 927                 }
 928         }
 929 fail:
 930         f2fs_put_dnode(&dn);
 931         return ret;
 932 }
 933
 934 /* return # of compressed blocks in compressed cluster */
 935 static int f2fs_compressed_blocks(struct compress_ctx *cc)
 936 {
 937         return __f2fs_cluster_blocks(cc, true);
 938 }
 939
 940 /* return # of valid blocks in compressed cluster */
 941 static int f2fs_cluster_blocks(struct compress_ctx *cc)
 942 {
 943         return __f2fs_cluster_blocks(cc, false);
 944 }
 945
 946 int f2fs_is_compressed_cluster(struct inode *inode, pgoff_t index)
 947 {
 948         struct compress_ctx cc = {
 949                 .inode = inode,
 950                 .log_cluster_size = F2FS_I(inode)->i_log_cluster_size,
 951                 .cluster_size = F2FS_I(inode)->i_cluster_size,
 952                 .cluster_idx = index >> F2FS_I(inode)->i_log_cluster_size,
 953         };
 954
 955         return f2fs_cluster_blocks(&cc);
 956 }
 957
 958 static bool cluster_may_compress(struct compress_ctx *cc)
 959 {
 960         if (!f2fs_need_compress_data(cc->inode))
 961                 return false;
 962         if (f2fs_is_atomic_file(cc->inode))
 963                 return false;
 964         if (f2fs_is_mmap_file(cc->inode))
 965                 return false;
 966         if (!f2fs_cluster_is_full(cc))
 967                 return false;
 968         if (unlikely(f2fs_cp_error(F2FS_I_SB(cc->inode))))
 969                 return false;
 970         return __cluster_may_compress(cc);
 971 }
 972
 973 static void set_cluster_writeback(struct compress_ctx *cc)
 974 {
 975         int i;
 976
 977         for (i = 0; i < cc->cluster_size; i++) {
 978                 if (cc->rpages[i])
 979                         set_page_writeback(cc->rpages[i]);
 980         }
 981 }
 982
 983 static void set_cluster_dirty(struct compress_ctx *cc)
 984 {
 985         int i;
 986
 987         for (i = 0; i < cc->cluster_size; i++)
 988                 if (cc->rpages[i])
 989                         set_page_dirty(cc->rpages[i]);
 990 }
 991
 992 static int prepare_compress_overwrite(struct compress_ctx *cc,
 993                 struct page **pagep, pgoff_t index, void **fsdata)
 994 {
 995         struct f2fs_sb_info *sbi = F2FS_I_SB(cc->inode);
 996         struct address_space *mapping = cc->inode->i_mapping;
 997         struct page *page;
 998         struct dnode_of_data dn;
 999         sector_t last_block_in_bio;
1000         unsigned fgp_flag = FGP_LOCK | FGP_WRITE | FGP_CREAT;
1001         pgoff_t start_idx = start_idx_of_cluster(cc);
1002         int i, ret;
1003         bool prealloc;
1004
1005 retry:
1006         ret = f2fs_cluster_blocks(cc);
1007         if (ret <= 0)
1008                 return ret;
1009
1010         /* compressed case */
1011         prealloc = (ret < cc->cluster_size);
1012
1013         ret = f2fs_init_compress_ctx(cc);
1014         if (ret)
1015                 return ret;
1016
1017         /* keep page reference to avoid page reclaim */
1018         for (i = 0; i < cc->cluster_size; i++) {
1019                 page = f2fs_pagecache_get_page(mapping, start_idx + i,
1020                                                         fgp_flag, GFP_NOFS);
1021                 if (!page) {
1022                         ret = -ENOMEM;
1023                         goto unlock_pages;
1024                 }
1025
1026                 if (PageUptodate(page))
1027                         f2fs_put_page(page, 1);
1028                 else
1029                         f2fs_compress_ctx_add_page(cc, page);
1030         }
1031
1032         if (!f2fs_cluster_is_empty(cc)) {
1033                 struct bio *bio = NULL;
1034
1035                 ret = f2fs_read_multi_pages(cc, &bio, cc->cluster_size,
1036                                         &last_block_in_bio, false, true);
1037                 f2fs_put_rpages(cc);
1038                 f2fs_destroy_compress_ctx(cc, true);
1039                 if (ret)
1040                         goto out;
1041                 if (bio)
1042                         f2fs_submit_bio(sbi, bio, DATA);
1043
1044                 ret = f2fs_init_compress_ctx(cc);
1045                 if (ret)
1046                         goto out;
1047         }
1048
1049         for (i = 0; i < cc->cluster_size; i++) {
1050                 f2fs_bug_on(sbi, cc->rpages[i]);
1051
1052                 page = find_lock_page(mapping, start_idx + i);
1053                 if (!page) {
1054                         /* page can be truncated */
1055                         goto release_and_retry;
1056                 }
1057
1058                 f2fs_wait_on_page_writeback(page, DATA, true, true);
1059                 f2fs_compress_ctx_add_page(cc, page);
1060
1061                 if (!PageUptodate(page)) {
1062 release_and_retry:
1063                         f2fs_put_rpages(cc);
1064                         f2fs_unlock_rpages(cc, i + 1);
1065                         f2fs_destroy_compress_ctx(cc, true);
1066                         goto retry;
1067                 }
1068         }
1069
1070         if (prealloc) {
1071                 f2fs_do_map_lock(sbi, F2FS_GET_BLOCK_PRE_AIO, true);
1072
1073                 set_new_dnode(&dn, cc->inode, NULL, NULL, 0);
1074
1075                 for (i = cc->cluster_size - 1; i > 0; i--) {
1076                         ret = f2fs_get_block(&dn, start_idx + i);
1077                         if (ret) {
1078                                 i = cc->cluster_size;
1079                                 break;
1080                         }
1081
1082                         if (dn.data_blkaddr != NEW_ADDR)
1083                                 break;
1084                 }
1085
1086                 f2fs_do_map_lock(sbi, F2FS_GET_BLOCK_PRE_AIO, false);
1087         }
1088
1089         if (likely(!ret)) {
1090                 *fsdata = cc->rpages;
1091                 *pagep = cc->rpages[offset_in_cluster(cc, index)];
1092                 return cc->cluster_size;
1093         }
1094
1095 unlock_pages:
1096         f2fs_put_rpages(cc);
1097         f2fs_unlock_rpages(cc, i);
1098         f2fs_destroy_compress_ctx(cc, true);
1099 out:
1100         return ret;
1101 }
1102
1103 int f2fs_prepare_compress_overwrite(struct inode *inode,
1104                 struct page **pagep, pgoff_t index, void **fsdata)
1105 {
1106         struct compress_ctx cc = {
1107                 .inode = inode,
1108                 .log_cluster_size = F2FS_I(inode)->i_log_cluster_size,
1109                 .cluster_size = F2FS_I(inode)->i_cluster_size,
1110                 .cluster_idx = index >> F2FS_I(inode)->i_log_cluster_size,
1111                 .rpages = NULL,
1112                 .nr_rpages = 0,
1113         };
1114
1115         return prepare_compress_overwrite(&cc, pagep, index, fsdata);
1116 }
1117
1118 bool f2fs_compress_write_end(struct inode *inode, void *fsdata,
1119                                         pgoff_t index, unsigned copied)
1120
1121 {
1122         struct compress_ctx cc = {
1123                 .inode = inode,
1124                 .log_cluster_size = F2FS_I(inode)->i_log_cluster_size,
1125                 .cluster_size = F2FS_I(inode)->i_cluster_size,
1126                 .rpages = fsdata,
1127         };
1128         bool first_index = (index == cc.rpages[0]->index);
1129
1130         if (copied)
1131                 set_cluster_dirty(&cc);
1132
1133         f2fs_put_rpages_wbc(&cc, NULL, false, 1);
1134         f2fs_destroy_compress_ctx(&cc, false);
1135
1136         return first_index;
1137 }
1138
1139 int f2fs_truncate_partial_cluster(struct inode *inode, u64 from, bool lock)
1140 {
1141         void *fsdata = NULL;
1142         struct page *pagep;
1143         int log_cluster_size = F2FS_I(inode)->i_log_cluster_size;
1144         pgoff_t start_idx = from >> (PAGE_SHIFT + log_cluster_size) <<
1145                                                         log_cluster_size;
1146         int err;
1147
1148         err = f2fs_is_compressed_cluster(inode, start_idx);
1149         if (err < 0)
1150                 return err;
1151
1152         /* truncate normal cluster */
1153         if (!err)
1154                 return f2fs_do_truncate_blocks(inode, from, lock);
1155
1156         /* truncate compressed cluster */
1157         err = f2fs_prepare_compress_overwrite(inode, &pagep,
1158                                                 start_idx, &fsdata);
1159
1160         /* should not be a normal cluster */
1161         f2fs_bug_on(F2FS_I_SB(inode), err == 0);
1162
1163         if (err <= 0)
1164                 return err;
1165
1166         if (err > 0) {
1167                 struct page **rpages = fsdata;
1168                 int cluster_size = F2FS_I(inode)->i_cluster_size;
1169                 int i;
1170
1171                 for (i = cluster_size - 1; i >= 0; i--) {
1172                         loff_t start = rpages[i]->index << PAGE_SHIFT;
1173
1174                         if (from <= start) {
1175                                 zero_user_segment(rpages[i], 0, PAGE_SIZE);
1176                         } else {
1177                                 zero_user_segment(rpages[i], from - start,
1178                                                                 PAGE_SIZE);
1179                                 break;
1180                         }
1181                 }
1182
1183                 f2fs_compress_write_end(inode, fsdata, start_idx, true);
1184         }
1185         return 0;
1186 }
1187
1188 static int f2fs_write_compressed_pages(struct compress_ctx *cc,
1189                                         int *submitted,
1190                                         struct writeback_control *wbc,
1191                                         enum iostat_type io_type)
1192 {
1193         struct inode *inode = cc->inode;
1194         struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
1195         struct f2fs_inode_info *fi = F2FS_I(inode);
1196         struct f2fs_io_info fio = {
1197                 .sbi = sbi,
1198                 .ino = cc->inode->i_ino,
1199                 .type = DATA,
1200                 .op = REQ_OP_WRITE,
1201                 .op_flags = wbc_to_write_flags(wbc),
1202                 .old_blkaddr = NEW_ADDR,
1203                 .page = NULL,
1204                 .encrypted_page = NULL,
1205                 .compressed_page = NULL,
1206                 .submitted = false,
1207                 .io_type = io_type,
1208                 .io_wbc = wbc,
1209                 .encrypted = fscrypt_inode_uses_fs_layer_crypto(cc->inode),
1210         };
1211         struct dnode_of_data dn;
1212         struct node_info ni;
1213         struct compress_io_ctx *cic;
1214         pgoff_t start_idx = start_idx_of_cluster(cc);
1215         unsigned int last_index = cc->cluster_size - 1;
1216         loff_t psize;
1217         int i, err;
1218
1219         if (IS_NOQUOTA(inode)) {
1220                 /*
1221                  * We need to wait for node_write to avoid block allocation during
1222                  * checkpoint. This can only happen to quota writes which can cause
1223                  * the below discard race condition.
1224                  */
1225                 down_read(&sbi->node_write);
1226         } else if (!f2fs_trylock_op(sbi)) {
1227                 goto out_free;
1228         }
1229
1230         set_new_dnode(&dn, cc->inode, NULL, NULL, 0);
1231
1232         err = f2fs_get_dnode_of_data(&dn, start_idx, LOOKUP_NODE);
1233         if (err)
1234                 goto out_unlock_op;
1235
1236         for (i = 0; i < cc->cluster_size; i++) {
1237                 if (data_blkaddr(dn.inode, dn.node_page,
1238                                         dn.ofs_in_node + i) == NULL_ADDR)
1239                         goto out_put_dnode;
1240         }
1241
1242         psize = (loff_t)(cc->rpages[last_index]->index + 1) << PAGE_SHIFT;
1243
1244         err = f2fs_get_node_info(fio.sbi, dn.nid, &ni);
1245         if (err)
1246                 goto out_put_dnode;
1247
1248         fio.version = ni.version;
1249
1250         cic = kmem_cache_zalloc(cic_entry_slab, GFP_NOFS);
1251         if (!cic)
1252                 goto out_put_dnode;
1253
1254         cic->magic = F2FS_COMPRESSED_PAGE_MAGIC;
1255         cic->inode = inode;
1256         atomic_set(&cic->pending_pages, cc->nr_cpages);
1257         cic->rpages = page_array_alloc(cc->inode, cc->cluster_size);
1258         if (!cic->rpages)
1259                 goto out_put_cic;
1260
1261         cic->nr_rpages = cc->cluster_size;
1262
1263         for (i = 0; i < cc->nr_cpages; i++) {
1264                 f2fs_set_compressed_page(cc->cpages[i], inode,
1265                                         cc->rpages[i + 1]->index, cic);
1266                 fio.compressed_page = cc->cpages[i];
1267
1268                 fio.old_blkaddr = data_blkaddr(dn.inode, dn.node_page,
1269                                                 dn.ofs_in_node + i + 1);
1270
1271                 /* wait for GCed page writeback via META_MAPPING */
1272                 f2fs_wait_on_block_writeback(inode, fio.old_blkaddr);
1273
1274                 if (fio.encrypted) {
1275                         fio.page = cc->rpages[i + 1];
1276                         err = f2fs_encrypt_one_page(&fio);
1277                         if (err)
1278                                 goto out_destroy_crypt;
1279                         cc->cpages[i] = fio.encrypted_page;
1280                 }
1281         }
1282
1283         set_cluster_writeback(cc);
1284
1285         for (i = 0; i < cc->cluster_size; i++)
1286                 cic->rpages[i] = cc->rpages[i];
1287
1288         for (i = 0; i < cc->cluster_size; i++, dn.ofs_in_node++) {
1289                 block_t blkaddr;
1290
1291                 blkaddr = f2fs_data_blkaddr(&dn);
1292                 fio.page = cc->rpages[i];
1293                 fio.old_blkaddr = blkaddr;
1294
1295                 /* cluster header */
1296                 if (i == 0) {
1297                         if (blkaddr == COMPRESS_ADDR)
1298                                 fio.compr_blocks++;
1299                         if (__is_valid_data_blkaddr(blkaddr))
1300                                 f2fs_invalidate_blocks(sbi, blkaddr);
1301                         f2fs_update_data_blkaddr(&dn, COMPRESS_ADDR);
1302                         goto unlock_continue;
1303                 }
1304
1305                 if (fio.compr_blocks && __is_valid_data_blkaddr(blkaddr))
1306                         fio.compr_blocks++;
1307
1308                 if (i > cc->nr_cpages) {
1309                         if (__is_valid_data_blkaddr(blkaddr)) {
1310                                 f2fs_invalidate_blocks(sbi, blkaddr);
1311                                 f2fs_update_data_blkaddr(&dn, NEW_ADDR);
1312                         }
1313                         goto unlock_continue;
1314                 }
1315
1316                 f2fs_bug_on(fio.sbi, blkaddr == NULL_ADDR);
1317
1318                 if (fio.encrypted)
1319                         fio.encrypted_page = cc->cpages[i - 1];
1320                 else
1321                         fio.compressed_page = cc->cpages[i - 1];
1322
1323                 cc->cpages[i - 1] = NULL;
1324                 f2fs_outplace_write_data(&dn, &fio);
1325                 (*submitted)++;
1326 unlock_continue:
1327                 inode_dec_dirty_pages(cc->inode);
1328                 unlock_page(fio.page);
1329         }
1330
1331         if (fio.compr_blocks)
1332                 f2fs_i_compr_blocks_update(inode, fio.compr_blocks - 1, false);
1333         f2fs_i_compr_blocks_update(inode, cc->nr_cpages, true);
1334         add_compr_block_stat(inode, cc->nr_cpages);
1335
1336         set_inode_flag(cc->inode, FI_APPEND_WRITE);
1337         if (cc->cluster_idx == 0)
1338                 set_inode_flag(inode, FI_FIRST_BLOCK_WRITTEN);
1339
1340         f2fs_put_dnode(&dn);
1341         if (IS_NOQUOTA(inode))
1342                 up_read(&sbi->node_write);
1343         else
1344                 f2fs_unlock_op(sbi);
1345
1346         spin_lock(&fi->i_size_lock);
1347         if (fi->last_disk_size < psize)
1348                 fi->last_disk_size = psize;
1349         spin_unlock(&fi->i_size_lock);
1350
1351         f2fs_put_rpages(cc);
1352         page_array_free(cc->inode, cc->cpages, cc->nr_cpages);
1353         cc->cpages = NULL;
1354         f2fs_destroy_compress_ctx(cc, false);
1355         return 0;
1356
1357 out_destroy_crypt:
1358         page_array_free(cc->inode, cic->rpages, cc->cluster_size);
1359
1360         for (--i; i >= 0; i--)
1361                 fscrypt_finalize_bounce_page(&cc->cpages[i]);
1362         for (i = 0; i < cc->nr_cpages; i++) {
1363                 if (!cc->cpages[i])
1364                         continue;
1365                 f2fs_compress_free_page(cc->cpages[i]);
1366                 cc->cpages[i] = NULL;
1367         }
1368 out_put_cic:
1369         kmem_cache_free(cic_entry_slab, cic);
1370 out_put_dnode:
1371         f2fs_put_dnode(&dn);
1372 out_unlock_op:
1373         if (IS_NOQUOTA(inode))
1374                 up_read(&sbi->node_write);
1375         else
1376                 f2fs_unlock_op(sbi);
1377 out_free:
1378         page_array_free(cc->inode, cc->cpages, cc->nr_cpages);
1379         cc->cpages = NULL;
1380         return -EAGAIN;
1381 }
1382
1383 void f2fs_compress_write_end_io(struct bio *bio, struct page *page)
1384 {
1385         struct f2fs_sb_info *sbi = bio->bi_private;
1386         struct compress_io_ctx *cic =
1387                         (struct compress_io_ctx *)page_private(page);
1388         int i;
1389
1390         if (unlikely(bio->bi_status))
1391                 mapping_set_error(cic->inode->i_mapping, -EIO);
1392
1393         f2fs_compress_free_page(page);
1394
1395         dec_page_count(sbi, F2FS_WB_DATA);
1396
1397         if (atomic_dec_return(&cic->pending_pages))
1398                 return;
1399
1400         for (i = 0; i < cic->nr_rpages; i++) {
1401                 WARN_ON(!cic->rpages[i]);
1402                 clear_cold_data(cic->rpages[i]);
1403                 end_page_writeback(cic->rpages[i]);
1404         }
1405
1406         page_array_free(cic->inode, cic->rpages, cic->nr_rpages);
1407         kmem_cache_free(cic_entry_slab, cic);
1408 }
1409
1410 static int f2fs_write_raw_pages(struct compress_ctx *cc,
1411                                         int *submitted,
1412                                         struct writeback_control *wbc,
1413                                         enum iostat_type io_type)
1414 {
1415         struct address_space *mapping = cc->inode->i_mapping;
1416         int _submitted, compr_blocks, ret;
1417         int i = -1, err = 0;
1418
1419         compr_blocks = f2fs_compressed_blocks(cc);
1420         if (compr_blocks < 0) {
1421                 err = compr_blocks;
1422                 goto out_err;
1423         }
1424
1425         for (i = 0; i < cc->cluster_size; i++) {
1426                 if (!cc->rpages[i])
1427                         continue;
1428 retry_write:
1429                 if (cc->rpages[i]->mapping != mapping) {
1430                         unlock_page(cc->rpages[i]);
1431                         continue;
1432                 }
1433
1434                 BUG_ON(!PageLocked(cc->rpages[i]));
1435
1436                 ret = f2fs_write_single_data_page(cc->rpages[i], &_submitted,
1437                                                 NULL, NULL, wbc, io_type,
1438                                                 compr_blocks, false);
1439                 if (ret) {
1440                         if (ret == AOP_WRITEPAGE_ACTIVATE) {
1441                                 unlock_page(cc->rpages[i]);
1442                                 ret = 0;
1443                         } else if (ret == -EAGAIN) {
1444                                 /*
1445                                  * for quota file, just redirty left pages to
1446                                  * avoid deadlock caused by cluster update race
1447                                  * from foreground operation.
1448                                  */
1449                                 if (IS_NOQUOTA(cc->inode)) {
1450                                         err = 0;
1451                                         goto out_err;
1452                                 }
1453                                 ret = 0;
1454                                 cond_resched();
1455                                 congestion_wait(BLK_RW_ASYNC,
1456                                                 DEFAULT_IO_TIMEOUT);
1457                                 lock_page(cc->rpages[i]);
1458
1459                                 if (!PageDirty(cc->rpages[i])) {
1460                                         unlock_page(cc->rpages[i]);
1461                                         continue;
1462                                 }
1463
1464                                 clear_page_dirty_for_io(cc->rpages[i]);
1465                                 goto retry_write;
1466                         }
1467                         err = ret;
1468                         goto out_err;
1469                 }
1470
1471                 *submitted += _submitted;
1472         }
1473
1474         f2fs_balance_fs(F2FS_M_SB(mapping), true);
1475
1476         return 0;
1477 out_err:
1478         for (++i; i < cc->cluster_size; i++) {
1479                 if (!cc->rpages[i])
1480                         continue;
1481                 redirty_page_for_writepage(wbc, cc->rpages[i]);
1482                 unlock_page(cc->rpages[i]);
1483         }
1484         return err;
1485 }
1486
1487 int f2fs_write_multi_pages(struct compress_ctx *cc,
1488                                         int *submitted,
1489                                         struct writeback_control *wbc,
1490                                         enum iostat_type io_type)
1491 {
1492         int err;
1493
1494         *submitted = 0;
1495         if (cluster_may_compress(cc)) {
1496                 err = f2fs_compress_pages(cc);
1497                 if (err == -EAGAIN) {
1498                         goto write;
1499                 } else if (err) {
1500                         f2fs_put_rpages_wbc(cc, wbc, true, 1);
1501                         goto destroy_out;
1502                 }
1503
1504                 err = f2fs_write_compressed_pages(cc, submitted,
1505                                                         wbc, io_type);
1506                 if (!err)
1507                         return 0;
1508                 f2fs_bug_on(F2FS_I_SB(cc->inode), err != -EAGAIN);
1509         }
1510 write:
1511         f2fs_bug_on(F2FS_I_SB(cc->inode), *submitted);
1512
1513         err = f2fs_write_raw_pages(cc, submitted, wbc, io_type);
1514         f2fs_put_rpages_wbc(cc, wbc, false, 0);
1515 destroy_out:
1516         f2fs_destroy_compress_ctx(cc, false);
1517         return err;
1518 }
1519
1520 static void f2fs_free_dic(struct decompress_io_ctx *dic);
1521
1522 struct decompress_io_ctx *f2fs_alloc_dic(struct compress_ctx *cc)
1523 {
1524         struct decompress_io_ctx *dic;
1525         pgoff_t start_idx = start_idx_of_cluster(cc);
1526         int i;
1527
1528         dic = kmem_cache_zalloc(dic_entry_slab, GFP_NOFS);
1529         if (!dic)
1530                 return ERR_PTR(-ENOMEM);
1531
1532         dic->rpages = page_array_alloc(cc->inode, cc->cluster_size);
1533         if (!dic->rpages) {
1534                 kmem_cache_free(dic_entry_slab, dic);
1535                 return ERR_PTR(-ENOMEM);
1536         }
1537
1538         dic->magic = F2FS_COMPRESSED_PAGE_MAGIC;
1539         dic->inode = cc->inode;
1540         atomic_set(&dic->remaining_pages, cc->nr_cpages);
1541         dic->cluster_idx = cc->cluster_idx;
1542         dic->cluster_size = cc->cluster_size;
1543         dic->log_cluster_size = cc->log_cluster_size;
1544         dic->nr_cpages = cc->nr_cpages;
1545         refcount_set(&dic->refcnt, 1);
1546         dic->failed = false;
1547         dic->need_verity = f2fs_need_verity(cc->inode, start_idx);
1548
1549         for (i = 0; i < dic->cluster_size; i++)
1550                 dic->rpages[i] = cc->rpages[i];
1551         dic->nr_rpages = cc->cluster_size;
1552
1553         dic->cpages = page_array_alloc(dic->inode, dic->nr_cpages);
1554         if (!dic->cpages)
1555                 goto out_free;
1556
1557         for (i = 0; i < dic->nr_cpages; i++) {
1558                 struct page *page;
1559
1560                 page = f2fs_compress_alloc_page();
1561                 if (!page)
1562                         goto out_free;
1563
1564                 f2fs_set_compressed_page(page, cc->inode,
1565                                         start_idx + i + 1, dic);
1566                 dic->cpages[i] = page;
1567         }
1568
1569         return dic;
1570
1571 out_free:
1572         f2fs_free_dic(dic);
1573         return ERR_PTR(-ENOMEM);
1574 }
1575
1576 static void f2fs_free_dic(struct decompress_io_ctx *dic)
1577 {
1578         int i;
1579
1580         if (dic->tpages) {
1581                 for (i = 0; i < dic->cluster_size; i++) {
1582                         if (dic->rpages[i])
1583                                 continue;
1584                         if (!dic->tpages[i])
1585                                 continue;
1586                         f2fs_compress_free_page(dic->tpages[i]);
1587                 }
1588                 page_array_free(dic->inode, dic->tpages, dic->cluster_size);
1589         }
1590
1591         if (dic->cpages) {
1592                 for (i = 0; i < dic->nr_cpages; i++) {
1593                         if (!dic->cpages[i])
1594                                 continue;
1595                         f2fs_compress_free_page(dic->cpages[i]);
1596                 }
1597                 page_array_free(dic->inode, dic->cpages, dic->nr_cpages);
1598         }
1599
1600         page_array_free(dic->inode, dic->rpages, dic->nr_rpages);
1601         kmem_cache_free(dic_entry_slab, dic);
1602 }
1603
1604 static void f2fs_put_dic(struct decompress_io_ctx *dic)
1605 {
1606         if (refcount_dec_and_test(&dic->refcnt))
1607                 f2fs_free_dic(dic);
1608 }
1609
1610 /*
1611  * Update and unlock the cluster's pagecache pages, and release the reference to
1612  * the decompress_io_ctx that was being held for I/O completion.
1613  */
1614 static void __f2fs_decompress_end_io(struct decompress_io_ctx *dic, bool failed)
1615 {
1616         int i;
1617
1618         for (i = 0; i < dic->cluster_size; i++) {
1619                 struct page *rpage = dic->rpages[i];
1620
1621                 if (!rpage)
1622                         continue;
1623
1624                 /* PG_error was set if verity failed. */
1625                 if (failed || PageError(rpage)) {
1626                         ClearPageUptodate(rpage);
1627                         /* will re-read again later */
1628                         ClearPageError(rpage);
1629                 } else {
1630                         SetPageUptodate(rpage);
1631                 }
1632                 unlock_page(rpage);
1633         }
1634
1635         f2fs_put_dic(dic);
1636 }
1637
1638 static void f2fs_verify_cluster(struct work_struct *work)
1639 {
1640         struct decompress_io_ctx *dic =
1641                 container_of(work, struct decompress_io_ctx, verity_work);
1642         int i;
1643
1644         /* Verify the cluster's decompressed pages with fs-verity. */
1645         for (i = 0; i < dic->cluster_size; i++) {
1646                 struct page *rpage = dic->rpages[i];
1647
1648                 if (rpage && !fsverity_verify_page(rpage))
1649                         SetPageError(rpage);
1650         }
1651
1652         __f2fs_decompress_end_io(dic, false);
1653 }
1654
1655 /*
1656  * This is called when a compressed cluster has been decompressed
1657  * (or failed to be read and/or decompressed).
1658  */
1659 void f2fs_decompress_end_io(struct decompress_io_ctx *dic, bool failed)
1660 {
1661         if (!failed && dic->need_verity) {
1662                 /*
1663                  * Note that to avoid deadlocks, the verity work can't be done
1664                  * on the decompression workqueue.  This is because verifying
1665                  * the data pages can involve reading metadata pages from the
1666                  * file, and these metadata pages may be compressed.
1667                  */
1668                 INIT_WORK(&dic->verity_work, f2fs_verify_cluster);
1669                 fsverity_enqueue_verify_work(&dic->verity_work);
1670         } else {
1671                 __f2fs_decompress_end_io(dic, failed);
1672         }
1673 }
1674
1675 /*
1676  * Put a reference to a compressed page's decompress_io_ctx.
1677  *
1678  * This is called when the page is no longer needed and can be freed.
1679  */
1680 void f2fs_put_page_dic(struct page *page)
1681 {
1682         struct decompress_io_ctx *dic =
1683                         (struct decompress_io_ctx *)page_private(page);
1684
1685         f2fs_put_dic(dic);
1686 }
1687
1688 int f2fs_init_page_array_cache(struct f2fs_sb_info *sbi)
1689 {
1690         dev_t dev = sbi->sb->s_bdev->bd_dev;
1691         char slab_name[32];
1692
1693         sprintf(slab_name, "f2fs_page_array_entry-%u:%u", MAJOR(dev), MINOR(dev));
1694
1695         sbi->page_array_slab_size = sizeof(struct page *) <<
1696                                         F2FS_OPTION(sbi).compress_log_size;
1697
1698         sbi->page_array_slab = f2fs_kmem_cache_create(slab_name,
1699                                         sbi->page_array_slab_size);
1700         if (!sbi->page_array_slab)
1701                 return -ENOMEM;
1702         return 0;
1703 }
1704
1705 void f2fs_destroy_page_array_cache(struct f2fs_sb_info *sbi)
1706 {
1707         kmem_cache_destroy(sbi->page_array_slab);
1708 }
1709
1710 static int __init f2fs_init_cic_cache(void)
1711 {
1712         cic_entry_slab = f2fs_kmem_cache_create("f2fs_cic_entry",
1713                                         sizeof(struct compress_io_ctx));
1714         if (!cic_entry_slab)
1715                 return -ENOMEM;
1716         return 0;
1717 }
1718
1719 static void f2fs_destroy_cic_cache(void)
1720 {
1721         kmem_cache_destroy(cic_entry_slab);
1722 }
1723
1724 static int __init f2fs_init_dic_cache(void)
1725 {
1726         dic_entry_slab = f2fs_kmem_cache_create("f2fs_dic_entry",
1727                                         sizeof(struct decompress_io_ctx));
1728         if (!dic_entry_slab)
1729                 return -ENOMEM;
1730         return 0;
1731 }
1732
1733 static void f2fs_destroy_dic_cache(void)
1734 {
1735         kmem_cache_destroy(dic_entry_slab);
1736 }
1737
1738 int __init f2fs_init_compress_cache(void)
1739 {
1740         int err;
1741
1742         err = f2fs_init_cic_cache();
1743         if (err)
1744                 goto out;
1745         err = f2fs_init_dic_cache();
1746         if (err)
1747                 goto free_cic;
1748         return 0;
1749 free_cic:
1750         f2fs_destroy_cic_cache();
1751 out:
1752         return -ENOMEM;
1753 }
1754
1755 void f2fs_destroy_compress_cache(void)
1756 {
1757         f2fs_destroy_dic_cache();
1758         f2fs_destroy_cic_cache();
1759 }