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
  15 #include "f2fs.h"
  16 #include "node.h"
  17 #include <trace/events/f2fs.h>
  18
  19 struct f2fs_compress_ops {
  20         int (*init_compress_ctx)(struct compress_ctx *cc);
  21         void (*destroy_compress_ctx)(struct compress_ctx *cc);
  22         int (*compress_pages)(struct compress_ctx *cc);
  23         int (*decompress_pages)(struct decompress_io_ctx *dic);
  24 };
  25
  26 static unsigned int offset_in_cluster(struct compress_ctx *cc, pgoff_t index)
  27 {
  28         return index & (cc->cluster_size - 1);
  29 }
  30
  31 static pgoff_t cluster_idx(struct compress_ctx *cc, pgoff_t index)
  32 {
  33         return index >> cc->log_cluster_size;
  34 }
  35
  36 static pgoff_t start_idx_of_cluster(struct compress_ctx *cc)
  37 {
  38         return cc->cluster_idx << cc->log_cluster_size;
  39 }
  40
  41 bool f2fs_is_compressed_page(struct page *page)
  42 {
  43         if (!PagePrivate(page))
  44                 return false;
  45         if (!page_private(page))
  46                 return false;
  47         if (IS_ATOMIC_WRITTEN_PAGE(page) || IS_DUMMY_WRITTEN_PAGE(page))
  48                 return false;
  49         f2fs_bug_on(F2FS_M_SB(page->mapping),
  50                 *((u32 *)page_private(page)) != F2FS_COMPRESSED_PAGE_MAGIC);
  51         return true;
  52 }
  53
  54 static void f2fs_set_compressed_page(struct page *page,
  55                 struct inode *inode, pgoff_t index, void *data, refcount_t *r)
  56 {
  57         SetPagePrivate(page);
  58         set_page_private(page, (unsigned long)data);
  59
  60         /* i_crypto_info and iv index */
  61         page->index = index;
  62         page->mapping = inode->i_mapping;
  63         if (r)
  64                 refcount_inc(r);
  65 }
  66
  67 static void f2fs_put_compressed_page(struct page *page)
  68 {
  69         set_page_private(page, (unsigned long)NULL);
  70         ClearPagePrivate(page);
  71         page->mapping = NULL;
  72         unlock_page(page);
  73         put_page(page);
  74 }
  75
  76 static void f2fs_drop_rpages(struct compress_ctx *cc, int len, bool unlock)
  77 {
  78         int i;
  79
  80         for (i = 0; i < len; i++) {
  81                 if (!cc->rpages[i])
  82                         continue;
  83                 if (unlock)
  84                         unlock_page(cc->rpages[i]);
  85                 else
  86                         put_page(cc->rpages[i]);
  87         }
  88 }
  89
  90 static void f2fs_put_rpages(struct compress_ctx *cc)
  91 {
  92         f2fs_drop_rpages(cc, cc->cluster_size, false);
  93 }
  94
  95 static void f2fs_unlock_rpages(struct compress_ctx *cc, int len)
  96 {
  97         f2fs_drop_rpages(cc, len, true);
  98 }
  99
 100 static void f2fs_put_rpages_mapping(struct compress_ctx *cc,
 101                                 struct address_space *mapping,
 102                                 pgoff_t start, int len)
 103 {
 104         int i;
 105
 106         for (i = 0; i < len; i++) {
 107                 struct page *page = find_get_page(mapping, start + i);
 108
 109                 put_page(page);
 110                 put_page(page);
 111         }
 112 }
 113
 114 static void f2fs_put_rpages_wbc(struct compress_ctx *cc,
 115                 struct writeback_control *wbc, bool redirty, int unlock)
 116 {
 117         unsigned int i;
 118
 119         for (i = 0; i < cc->cluster_size; i++) {
 120                 if (!cc->rpages[i])
 121                         continue;
 122                 if (redirty)
 123                         redirty_page_for_writepage(wbc, cc->rpages[i]);
 124                 f2fs_put_page(cc->rpages[i], unlock);
 125         }
 126 }
 127
 128 struct page *f2fs_compress_control_page(struct page *page)
 129 {
 130         return ((struct compress_io_ctx *)page_private(page))->rpages[0];
 131 }
 132
 133 int f2fs_init_compress_ctx(struct compress_ctx *cc)
 134 {
 135         struct f2fs_sb_info *sbi = F2FS_I_SB(cc->inode);
 136
 137         if (cc->nr_rpages)
 138                 return 0;
 139
 140         cc->rpages = f2fs_kzalloc(sbi, sizeof(struct page *) <<
 141                                         cc->log_cluster_size, GFP_NOFS);
 142         return cc->rpages ? 0 : -ENOMEM;
 143 }
 144
 145 void f2fs_destroy_compress_ctx(struct compress_ctx *cc)
 146 {
 147         kfree(cc->rpages);
 148         cc->rpages = NULL;
 149         cc->nr_rpages = 0;
 150         cc->nr_cpages = 0;
 151         cc->cluster_idx = NULL_CLUSTER;
 152 }
 153
 154 void f2fs_compress_ctx_add_page(struct compress_ctx *cc, struct page *page)
 155 {
 156         unsigned int cluster_ofs;
 157
 158         if (!f2fs_cluster_can_merge_page(cc, page->index))
 159                 f2fs_bug_on(F2FS_I_SB(cc->inode), 1);
 160
 161         cluster_ofs = offset_in_cluster(cc, page->index);
 162         cc->rpages[cluster_ofs] = page;
 163         cc->nr_rpages++;
 164         cc->cluster_idx = cluster_idx(cc, page->index);
 165 }
 166
 167 #ifdef CONFIG_F2FS_FS_LZO
 168 static int lzo_init_compress_ctx(struct compress_ctx *cc)
 169 {
 170         cc->private = f2fs_kvmalloc(F2FS_I_SB(cc->inode),
 171                                 LZO1X_MEM_COMPRESS, GFP_NOFS);
 172         if (!cc->private)
 173                 return -ENOMEM;
 174
 175         cc->clen = lzo1x_worst_compress(PAGE_SIZE << cc->log_cluster_size);
 176         return 0;
 177 }
 178
 179 static void lzo_destroy_compress_ctx(struct compress_ctx *cc)
 180 {
 181         kvfree(cc->private);
 182         cc->private = NULL;
 183 }
 184
 185 static int lzo_compress_pages(struct compress_ctx *cc)
 186 {
 187         int ret;
 188
 189         ret = lzo1x_1_compress(cc->rbuf, cc->rlen, cc->cbuf->cdata,
 190                                         &cc->clen, cc->private);
 191         if (ret != LZO_E_OK) {
 192                 printk_ratelimited("%sF2FS-fs (%s): lzo compress failed, ret:%d\n",
 193                                 KERN_ERR, F2FS_I_SB(cc->inode)->sb->s_id, ret);
 194                 return -EIO;
 195         }
 196         return 0;
 197 }
 198
 199 static int lzo_decompress_pages(struct decompress_io_ctx *dic)
 200 {
 201         int ret;
 202
 203         ret = lzo1x_decompress_safe(dic->cbuf->cdata, dic->clen,
 204                                                 dic->rbuf, &dic->rlen);
 205         if (ret != LZO_E_OK) {
 206                 printk_ratelimited("%sF2FS-fs (%s): lzo decompress failed, ret:%d\n",
 207                                 KERN_ERR, F2FS_I_SB(dic->inode)->sb->s_id, ret);
 208                 return -EIO;
 209         }
 210
 211         if (dic->rlen != PAGE_SIZE << dic->log_cluster_size) {
 212                 printk_ratelimited("%sF2FS-fs (%s): lzo invalid rlen:%zu, "
 213                                         "expected:%lu\n", KERN_ERR,
 214                                         F2FS_I_SB(dic->inode)->sb->s_id,
 215                                         dic->rlen,
 216                                         PAGE_SIZE << dic->log_cluster_size);
 217                 return -EIO;
 218         }
 219         return 0;
 220 }
 221
 222 static const struct f2fs_compress_ops f2fs_lzo_ops = {
 223         .init_compress_ctx      = lzo_init_compress_ctx,
 224         .destroy_compress_ctx   = lzo_destroy_compress_ctx,
 225         .compress_pages         = lzo_compress_pages,
 226         .decompress_pages       = lzo_decompress_pages,
 227 };
 228 #endif
 229
 230 #ifdef CONFIG_F2FS_FS_LZ4
 231 static int lz4_init_compress_ctx(struct compress_ctx *cc)
 232 {
 233         cc->private = f2fs_kvmalloc(F2FS_I_SB(cc->inode),
 234                                 LZ4_MEM_COMPRESS, GFP_NOFS);
 235         if (!cc->private)
 236                 return -ENOMEM;
 237
 238         cc->clen = LZ4_compressBound(PAGE_SIZE << cc->log_cluster_size);
 239         return 0;
 240 }
 241
 242 static void lz4_destroy_compress_ctx(struct compress_ctx *cc)
 243 {
 244         kvfree(cc->private);
 245         cc->private = NULL;
 246 }
 247
 248 static int lz4_compress_pages(struct compress_ctx *cc)
 249 {
 250         int len;
 251
 252         len = LZ4_compress_default(cc->rbuf, cc->cbuf->cdata, cc->rlen,
 253                                                 cc->clen, cc->private);
 254         if (!len) {
 255                 printk_ratelimited("%sF2FS-fs (%s): lz4 compress failed\n",
 256                                 KERN_ERR, F2FS_I_SB(cc->inode)->sb->s_id);
 257                 return -EIO;
 258         }
 259         cc->clen = len;
 260         return 0;
 261 }
 262
 263 static int lz4_decompress_pages(struct decompress_io_ctx *dic)
 264 {
 265         int ret;
 266
 267         ret = LZ4_decompress_safe(dic->cbuf->cdata, dic->rbuf,
 268                                                 dic->clen, dic->rlen);
 269         if (ret < 0) {
 270                 printk_ratelimited("%sF2FS-fs (%s): lz4 decompress failed, ret:%d\n",
 271                                 KERN_ERR, F2FS_I_SB(dic->inode)->sb->s_id, ret);
 272                 return -EIO;
 273         }
 274
 275         if (ret != PAGE_SIZE << dic->log_cluster_size) {
 276                 printk_ratelimited("%sF2FS-fs (%s): lz4 invalid rlen:%zu, "
 277                                         "expected:%lu\n", KERN_ERR,
 278                                         F2FS_I_SB(dic->inode)->sb->s_id,
 279                                         dic->rlen,
 280                                         PAGE_SIZE << dic->log_cluster_size);
 281                 return -EIO;
 282         }
 283         return 0;
 284 }
 285
 286 static const struct f2fs_compress_ops f2fs_lz4_ops = {
 287         .init_compress_ctx      = lz4_init_compress_ctx,
 288         .destroy_compress_ctx   = lz4_destroy_compress_ctx,
 289         .compress_pages         = lz4_compress_pages,
 290         .decompress_pages       = lz4_decompress_pages,
 291 };
 292 #endif
 293
 294 static const struct f2fs_compress_ops *f2fs_cops[COMPRESS_MAX] = {
 295 #ifdef CONFIG_F2FS_FS_LZO
 296         &f2fs_lzo_ops,
 297 #else
 298         NULL,
 299 #endif
 300 #ifdef CONFIG_F2FS_FS_LZ4
 301         &f2fs_lz4_ops,
 302 #else
 303         NULL,
 304 #endif
 305 };
 306
 307 bool f2fs_is_compress_backend_ready(struct inode *inode)
 308 {
 309         if (!f2fs_compressed_file(inode))
 310                 return true;
 311         return f2fs_cops[F2FS_I(inode)->i_compress_algorithm];
 312 }
 313
 314 static struct page *f2fs_grab_page(void)
 315 {
 316         struct page *page;
 317
 318         page = alloc_page(GFP_NOFS);
 319         if (!page)
 320                 return NULL;
 321         lock_page(page);
 322         return page;
 323 }
 324
 325 static int f2fs_compress_pages(struct compress_ctx *cc)
 326 {
 327         struct f2fs_sb_info *sbi = F2FS_I_SB(cc->inode);
 328         struct f2fs_inode_info *fi = F2FS_I(cc->inode);
 329         const struct f2fs_compress_ops *cops =
 330                                 f2fs_cops[fi->i_compress_algorithm];
 331         unsigned int max_len, nr_cpages;
 332         int i, ret;
 333
 334         trace_f2fs_compress_pages_start(cc->inode, cc->cluster_idx,
 335                                 cc->cluster_size, fi->i_compress_algorithm);
 336
 337         ret = cops->init_compress_ctx(cc);
 338         if (ret)
 339                 goto out;
 340
 341         max_len = COMPRESS_HEADER_SIZE + cc->clen;
 342         cc->nr_cpages = DIV_ROUND_UP(max_len, PAGE_SIZE);
 343
 344         cc->cpages = f2fs_kzalloc(sbi, sizeof(struct page *) *
 345                                         cc->nr_cpages, GFP_NOFS);
 346         if (!cc->cpages) {
 347                 ret = -ENOMEM;
 348                 goto destroy_compress_ctx;
 349         }
 350
 351         for (i = 0; i < cc->nr_cpages; i++) {
 352                 cc->cpages[i] = f2fs_grab_page();
 353                 if (!cc->cpages[i]) {
 354                         ret = -ENOMEM;
 355                         goto out_free_cpages;
 356                 }
 357         }
 358
 359         cc->rbuf = vmap(cc->rpages, cc->cluster_size, VM_MAP, PAGE_KERNEL_RO);
 360         if (!cc->rbuf) {
 361                 ret = -ENOMEM;
 362                 goto out_free_cpages;
 363         }
 364
 365         cc->cbuf = vmap(cc->cpages, cc->nr_cpages, VM_MAP, PAGE_KERNEL);
 366         if (!cc->cbuf) {
 367                 ret = -ENOMEM;
 368                 goto out_vunmap_rbuf;
 369         }
 370
 371         ret = cops->compress_pages(cc);
 372         if (ret)
 373                 goto out_vunmap_cbuf;
 374
 375         max_len = PAGE_SIZE * (cc->cluster_size - 1) - COMPRESS_HEADER_SIZE;
 376
 377         if (cc->clen > max_len) {
 378                 ret = -EAGAIN;
 379                 goto out_vunmap_cbuf;
 380         }
 381
 382         cc->cbuf->clen = cpu_to_le32(cc->clen);
 383
 384         for (i = 0; i < COMPRESS_DATA_RESERVED_SIZE; i++)
 385                 cc->cbuf->reserved[i] = cpu_to_le32(0);
 386
 387         nr_cpages = DIV_ROUND_UP(cc->clen + COMPRESS_HEADER_SIZE, PAGE_SIZE);
 388
 389         /* zero out any unused part of the last page */
 390         memset(&cc->cbuf->cdata[cc->clen], 0,
 391                (nr_cpages * PAGE_SIZE) - (cc->clen + COMPRESS_HEADER_SIZE));
 392
 393         vunmap(cc->cbuf);
 394         vunmap(cc->rbuf);
 395
 396         for (i = nr_cpages; i < cc->nr_cpages; i++) {
 397                 f2fs_put_compressed_page(cc->cpages[i]);
 398                 cc->cpages[i] = NULL;
 399         }
 400
 401         cc->nr_cpages = nr_cpages;
 402
 403         trace_f2fs_compress_pages_end(cc->inode, cc->cluster_idx,
 404                                                         cc->clen, ret);
 405         return 0;
 406
 407 out_vunmap_cbuf:
 408         vunmap(cc->cbuf);
 409 out_vunmap_rbuf:
 410         vunmap(cc->rbuf);
 411 out_free_cpages:
 412         for (i = 0; i < cc->nr_cpages; i++) {
 413                 if (cc->cpages[i])
 414                         f2fs_put_compressed_page(cc->cpages[i]);
 415         }
 416         kfree(cc->cpages);
 417         cc->cpages = NULL;
 418 destroy_compress_ctx:
 419         cops->destroy_compress_ctx(cc);
 420 out:
 421         trace_f2fs_compress_pages_end(cc->inode, cc->cluster_idx,
 422                                                         cc->clen, ret);
 423         return ret;
 424 }
 425
 426 void f2fs_decompress_pages(struct bio *bio, struct page *page, bool verity)
 427 {
 428         struct decompress_io_ctx *dic =
 429                         (struct decompress_io_ctx *)page_private(page);
 430         struct f2fs_sb_info *sbi = F2FS_I_SB(dic->inode);
 431         struct f2fs_inode_info *fi= F2FS_I(dic->inode);
 432         const struct f2fs_compress_ops *cops =
 433                         f2fs_cops[fi->i_compress_algorithm];
 434         int ret;
 435
 436         dec_page_count(sbi, F2FS_RD_DATA);
 437
 438         if (bio->bi_status || PageError(page))
 439                 dic->failed = true;
 440
 441         if (refcount_dec_not_one(&dic->ref))
 442                 return;
 443
 444         trace_f2fs_decompress_pages_start(dic->inode, dic->cluster_idx,
 445                                 dic->cluster_size, fi->i_compress_algorithm);
 446
 447         /* submit partial compressed pages */
 448         if (dic->failed) {
 449                 ret = -EIO;
 450                 goto out_free_dic;
 451         }
 452
 453         dic->rbuf = vmap(dic->tpages, dic->cluster_size, VM_MAP, PAGE_KERNEL);
 454         if (!dic->rbuf) {
 455                 ret = -ENOMEM;
 456                 goto out_free_dic;
 457         }
 458
 459         dic->cbuf = vmap(dic->cpages, dic->nr_cpages, VM_MAP, PAGE_KERNEL_RO);
 460         if (!dic->cbuf) {
 461                 ret = -ENOMEM;
 462                 goto out_vunmap_rbuf;
 463         }
 464
 465         dic->clen = le32_to_cpu(dic->cbuf->clen);
 466         dic->rlen = PAGE_SIZE << dic->log_cluster_size;
 467
 468         if (dic->clen > PAGE_SIZE * dic->nr_cpages - COMPRESS_HEADER_SIZE) {
 469                 ret = -EFSCORRUPTED;
 470                 goto out_vunmap_cbuf;
 471         }
 472
 473         ret = cops->decompress_pages(dic);
 474
 475 out_vunmap_cbuf:
 476         vunmap(dic->cbuf);
 477 out_vunmap_rbuf:
 478         vunmap(dic->rbuf);
 479 out_free_dic:
 480         if (!verity)
 481                 f2fs_decompress_end_io(dic->rpages, dic->cluster_size,
 482                                                                 ret, false);
 483
 484         trace_f2fs_decompress_pages_end(dic->inode, dic->cluster_idx,
 485                                                         dic->clen, ret);
 486         if (!verity)
 487                 f2fs_free_dic(dic);
 488 }
 489
 490 static bool is_page_in_cluster(struct compress_ctx *cc, pgoff_t index)
 491 {
 492         if (cc->cluster_idx == NULL_CLUSTER)
 493                 return true;
 494         return cc->cluster_idx == cluster_idx(cc, index);
 495 }
 496
 497 bool f2fs_cluster_is_empty(struct compress_ctx *cc)
 498 {
 499         return cc->nr_rpages == 0;
 500 }
 501
 502 static bool f2fs_cluster_is_full(struct compress_ctx *cc)
 503 {
 504         return cc->cluster_size == cc->nr_rpages;
 505 }
 506
 507 bool f2fs_cluster_can_merge_page(struct compress_ctx *cc, pgoff_t index)
 508 {
 509         if (f2fs_cluster_is_empty(cc))
 510                 return true;
 511         return is_page_in_cluster(cc, index);
 512 }
 513
 514 static bool __cluster_may_compress(struct compress_ctx *cc)
 515 {
 516         struct f2fs_sb_info *sbi = F2FS_I_SB(cc->inode);
 517         loff_t i_size = i_size_read(cc->inode);
 518         unsigned nr_pages = DIV_ROUND_UP(i_size, PAGE_SIZE);
 519         int i;
 520
 521         for (i = 0; i < cc->cluster_size; i++) {
 522                 struct page *page = cc->rpages[i];
 523
 524                 f2fs_bug_on(sbi, !page);
 525
 526                 if (unlikely(f2fs_cp_error(sbi)))
 527                         return false;
 528                 if (unlikely(is_sbi_flag_set(sbi, SBI_POR_DOING)))
 529                         return false;
 530
 531                 /* beyond EOF */
 532                 if (page->index >= nr_pages)
 533                         return false;
 534         }
 535         return true;
 536 }
 537
 538 /* return # of compressed block addresses */
 539 static int f2fs_compressed_blocks(struct compress_ctx *cc)
 540 {
 541         struct dnode_of_data dn;
 542         int ret;
 543
 544         set_new_dnode(&dn, cc->inode, NULL, NULL, 0);
 545         ret = f2fs_get_dnode_of_data(&dn, start_idx_of_cluster(cc),
 546                                                         LOOKUP_NODE);
 547         if (ret) {
 548                 if (ret == -ENOENT)
 549                         ret = 0;
 550                 goto fail;
 551         }
 552
 553         if (dn.data_blkaddr == COMPRESS_ADDR) {
 554                 int i;
 555
 556                 ret = 1;
 557                 for (i = 1; i < cc->cluster_size; i++) {
 558                         block_t blkaddr;
 559
 560                         blkaddr = data_blkaddr(dn.inode,
 561                                         dn.node_page, dn.ofs_in_node + i);
 562                         if (blkaddr != NULL_ADDR)
 563                                 ret++;
 564                 }
 565         }
 566 fail:
 567         f2fs_put_dnode(&dn);
 568         return ret;
 569 }
 570
 571 int f2fs_is_compressed_cluster(struct inode *inode, pgoff_t index)
 572 {
 573         struct compress_ctx cc = {
 574                 .inode = inode,
 575                 .log_cluster_size = F2FS_I(inode)->i_log_cluster_size,
 576                 .cluster_size = F2FS_I(inode)->i_cluster_size,
 577                 .cluster_idx = index >> F2FS_I(inode)->i_log_cluster_size,
 578         };
 579
 580         return f2fs_compressed_blocks(&cc);
 581 }
 582
 583 static bool cluster_may_compress(struct compress_ctx *cc)
 584 {
 585         if (!f2fs_compressed_file(cc->inode))
 586                 return false;
 587         if (f2fs_is_atomic_file(cc->inode))
 588                 return false;
 589         if (f2fs_is_mmap_file(cc->inode))
 590                 return false;
 591         if (!f2fs_cluster_is_full(cc))
 592                 return false;
 593         return __cluster_may_compress(cc);
 594 }
 595
 596 static void set_cluster_writeback(struct compress_ctx *cc)
 597 {
 598         int i;
 599
 600         for (i = 0; i < cc->cluster_size; i++) {
 601                 if (cc->rpages[i])
 602                         set_page_writeback(cc->rpages[i]);
 603         }
 604 }
 605
 606 static void set_cluster_dirty(struct compress_ctx *cc)
 607 {
 608         int i;
 609
 610         for (i = 0; i < cc->cluster_size; i++)
 611                 if (cc->rpages[i])
 612                         set_page_dirty(cc->rpages[i]);
 613 }
 614
 615 static int prepare_compress_overwrite(struct compress_ctx *cc,
 616                 struct page **pagep, pgoff_t index, void **fsdata)
 617 {
 618         struct f2fs_sb_info *sbi = F2FS_I_SB(cc->inode);
 619         struct address_space *mapping = cc->inode->i_mapping;
 620         struct page *page;
 621         struct dnode_of_data dn;
 622         sector_t last_block_in_bio;
 623         unsigned fgp_flag = FGP_LOCK | FGP_WRITE | FGP_CREAT;
 624         pgoff_t start_idx = start_idx_of_cluster(cc);
 625         int i, ret;
 626         bool prealloc;
 627
 628 retry:
 629         ret = f2fs_compressed_blocks(cc);
 630         if (ret <= 0)
 631                 return ret;
 632
 633         /* compressed case */
 634         prealloc = (ret < cc->cluster_size);
 635
 636         ret = f2fs_init_compress_ctx(cc);
 637         if (ret)
 638                 return ret;
 639
 640         /* keep page reference to avoid page reclaim */
 641         for (i = 0; i < cc->cluster_size; i++) {
 642                 page = f2fs_pagecache_get_page(mapping, start_idx + i,
 643                                                         fgp_flag, GFP_NOFS);
 644                 if (!page) {
 645                         ret = -ENOMEM;
 646                         goto unlock_pages;
 647                 }
 648
 649                 if (PageUptodate(page))
 650                         unlock_page(page);
 651                 else
 652                         f2fs_compress_ctx_add_page(cc, page);
 653         }
 654
 655         if (!f2fs_cluster_is_empty(cc)) {
 656                 struct bio *bio = NULL;
 657
 658                 ret = f2fs_read_multi_pages(cc, &bio, cc->cluster_size,
 659                                                 &last_block_in_bio, false);
 660                 f2fs_destroy_compress_ctx(cc);
 661                 if (ret)
 662                         goto release_pages;
 663                 if (bio)
 664                         f2fs_submit_bio(sbi, bio, DATA);
 665
 666                 ret = f2fs_init_compress_ctx(cc);
 667                 if (ret)
 668                         goto release_pages;
 669         }
 670
 671         for (i = 0; i < cc->cluster_size; i++) {
 672                 f2fs_bug_on(sbi, cc->rpages[i]);
 673
 674                 page = find_lock_page(mapping, start_idx + i);
 675                 f2fs_bug_on(sbi, !page);
 676
 677                 f2fs_wait_on_page_writeback(page, DATA, true, true);
 678
 679                 f2fs_compress_ctx_add_page(cc, page);
 680                 f2fs_put_page(page, 0);
 681
 682                 if (!PageUptodate(page)) {
 683                         f2fs_unlock_rpages(cc, i + 1);
 684                         f2fs_put_rpages_mapping(cc, mapping, start_idx,
 685                                         cc->cluster_size);
 686                         f2fs_destroy_compress_ctx(cc);
 687                         goto retry;
 688                 }
 689         }
 690
 691         if (prealloc) {
 692                 __do_map_lock(sbi, F2FS_GET_BLOCK_PRE_AIO, true);
 693
 694                 set_new_dnode(&dn, cc->inode, NULL, NULL, 0);
 695
 696                 for (i = cc->cluster_size - 1; i > 0; i--) {
 697                         ret = f2fs_get_block(&dn, start_idx + i);
 698                         if (ret) {
 699                                 i = cc->cluster_size;
 700                                 break;
 701                         }
 702
 703                         if (dn.data_blkaddr != NEW_ADDR)
 704                                 break;
 705                 }
 706
 707                 __do_map_lock(sbi, F2FS_GET_BLOCK_PRE_AIO, false);
 708         }
 709
 710         if (likely(!ret)) {
 711                 *fsdata = cc->rpages;
 712                 *pagep = cc->rpages[offset_in_cluster(cc, index)];
 713                 return cc->cluster_size;
 714         }
 715
 716 unlock_pages:
 717         f2fs_unlock_rpages(cc, i);
 718 release_pages:
 719         f2fs_put_rpages_mapping(cc, mapping, start_idx, i);
 720         f2fs_destroy_compress_ctx(cc);
 721         return ret;
 722 }
 723
 724 int f2fs_prepare_compress_overwrite(struct inode *inode,
 725                 struct page **pagep, pgoff_t index, void **fsdata)
 726 {
 727         struct compress_ctx cc = {
 728                 .inode = inode,
 729                 .log_cluster_size = F2FS_I(inode)->i_log_cluster_size,
 730                 .cluster_size = F2FS_I(inode)->i_cluster_size,
 731                 .cluster_idx = index >> F2FS_I(inode)->i_log_cluster_size,
 732                 .rpages = NULL,
 733                 .nr_rpages = 0,
 734         };
 735
 736         return prepare_compress_overwrite(&cc, pagep, index, fsdata);
 737 }
 738
 739 bool f2fs_compress_write_end(struct inode *inode, void *fsdata,
 740                                         pgoff_t index, unsigned copied)
 741
 742 {
 743         struct compress_ctx cc = {
 744                 .log_cluster_size = F2FS_I(inode)->i_log_cluster_size,
 745                 .cluster_size = F2FS_I(inode)->i_cluster_size,
 746                 .rpages = fsdata,
 747         };
 748         bool first_index = (index == cc.rpages[0]->index);
 749
 750         if (copied)
 751                 set_cluster_dirty(&cc);
 752
 753         f2fs_put_rpages_wbc(&cc, NULL, false, 1);
 754         f2fs_destroy_compress_ctx(&cc);
 755
 756         return first_index;
 757 }
 758
 759 static int f2fs_write_compressed_pages(struct compress_ctx *cc,
 760                                         int *submitted,
 761                                         struct writeback_control *wbc,
 762                                         enum iostat_type io_type)
 763 {
 764         struct inode *inode = cc->inode;
 765         struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
 766         struct f2fs_inode_info *fi = F2FS_I(inode);
 767         struct f2fs_io_info fio = {
 768                 .sbi = sbi,
 769                 .ino = cc->inode->i_ino,
 770                 .type = DATA,
 771                 .op = REQ_OP_WRITE,
 772                 .op_flags = wbc_to_write_flags(wbc),
 773                 .old_blkaddr = NEW_ADDR,
 774                 .page = NULL,
 775                 .encrypted_page = NULL,
 776                 .compressed_page = NULL,
 777                 .submitted = false,
 778                 .io_type = io_type,
 779                 .io_wbc = wbc,
 780                 .encrypted = f2fs_encrypted_file(cc->inode),
 781         };
 782         struct dnode_of_data dn;
 783         struct node_info ni;
 784         struct compress_io_ctx *cic;
 785         pgoff_t start_idx = start_idx_of_cluster(cc);
 786         unsigned int last_index = cc->cluster_size - 1;
 787         loff_t psize;
 788         int i, err;
 789
 790         if (!f2fs_trylock_op(sbi))
 791                 return -EAGAIN;
 792
 793         set_new_dnode(&dn, cc->inode, NULL, NULL, 0);
 794
 795         err = f2fs_get_dnode_of_data(&dn, start_idx, LOOKUP_NODE);
 796         if (err)
 797                 goto out_unlock_op;
 798
 799         for (i = 0; i < cc->cluster_size; i++) {
 800                 if (data_blkaddr(dn.inode, dn.node_page,
 801                                         dn.ofs_in_node + i) == NULL_ADDR)
 802                         goto out_put_dnode;
 803         }
 804
 805         psize = (loff_t)(cc->rpages[last_index]->index + 1) << PAGE_SHIFT;
 806
 807         err = f2fs_get_node_info(fio.sbi, dn.nid, &ni);
 808         if (err)
 809                 goto out_put_dnode;
 810
 811         fio.version = ni.version;
 812
 813         cic = f2fs_kzalloc(sbi, sizeof(struct compress_io_ctx), GFP_NOFS);
 814         if (!cic)
 815                 goto out_put_dnode;
 816
 817         cic->magic = F2FS_COMPRESSED_PAGE_MAGIC;
 818         cic->inode = inode;
 819         refcount_set(&cic->ref, 1);
 820         cic->rpages = f2fs_kzalloc(sbi, sizeof(struct page *) <<
 821                         cc->log_cluster_size, GFP_NOFS);
 822         if (!cic->rpages)
 823                 goto out_put_cic;
 824
 825         cic->nr_rpages = cc->cluster_size;
 826
 827         for (i = 0; i < cc->nr_cpages; i++) {
 828                 f2fs_set_compressed_page(cc->cpages[i], inode,
 829                                         cc->rpages[i + 1]->index,
 830                                         cic, i ? &cic->ref : NULL);
 831                 fio.compressed_page = cc->cpages[i];
 832                 if (fio.encrypted) {
 833                         fio.page = cc->rpages[i + 1];
 834                         err = f2fs_encrypt_one_page(&fio);
 835                         if (err)
 836                                 goto out_destroy_crypt;
 837                         cc->cpages[i] = fio.encrypted_page;
 838                 }
 839         }
 840
 841         set_cluster_writeback(cc);
 842
 843         for (i = 0; i < cc->cluster_size; i++)
 844                 cic->rpages[i] = cc->rpages[i];
 845
 846         for (i = 0; i < cc->cluster_size; i++, dn.ofs_in_node++) {
 847                 block_t blkaddr;
 848
 849                 blkaddr = f2fs_data_blkaddr(&dn);
 850                 fio.page = cc->rpages[i];
 851                 fio.old_blkaddr = blkaddr;
 852
 853                 /* cluster header */
 854                 if (i == 0) {
 855                         if (blkaddr == COMPRESS_ADDR)
 856                                 fio.compr_blocks++;
 857                         if (__is_valid_data_blkaddr(blkaddr))
 858                                 f2fs_invalidate_blocks(sbi, blkaddr);
 859                         f2fs_update_data_blkaddr(&dn, COMPRESS_ADDR);
 860                         goto unlock_continue;
 861                 }
 862
 863                 if (fio.compr_blocks && __is_valid_data_blkaddr(blkaddr))
 864                         fio.compr_blocks++;
 865
 866                 if (i > cc->nr_cpages) {
 867                         if (__is_valid_data_blkaddr(blkaddr)) {
 868                                 f2fs_invalidate_blocks(sbi, blkaddr);
 869                                 f2fs_update_data_blkaddr(&dn, NEW_ADDR);
 870                         }
 871                         goto unlock_continue;
 872                 }
 873
 874                 f2fs_bug_on(fio.sbi, blkaddr == NULL_ADDR);
 875
 876                 if (fio.encrypted)
 877                         fio.encrypted_page = cc->cpages[i - 1];
 878                 else
 879                         fio.compressed_page = cc->cpages[i - 1];
 880
 881                 cc->cpages[i - 1] = NULL;
 882                 f2fs_outplace_write_data(&dn, &fio);
 883                 (*submitted)++;
 884 unlock_continue:
 885                 inode_dec_dirty_pages(cc->inode);
 886                 unlock_page(fio.page);
 887         }
 888
 889         if (fio.compr_blocks)
 890                 f2fs_i_compr_blocks_update(inode, fio.compr_blocks - 1, false);
 891         f2fs_i_compr_blocks_update(inode, cc->nr_cpages, true);
 892
 893         set_inode_flag(cc->inode, FI_APPEND_WRITE);
 894         if (cc->cluster_idx == 0)
 895                 set_inode_flag(inode, FI_FIRST_BLOCK_WRITTEN);
 896
 897         f2fs_put_dnode(&dn);
 898         f2fs_unlock_op(sbi);
 899
 900         spin_lock(&fi->i_size_lock);
 901         if (fi->last_disk_size < psize)
 902                 fi->last_disk_size = psize;
 903         spin_unlock(&fi->i_size_lock);
 904
 905         f2fs_put_rpages(cc);
 906         f2fs_destroy_compress_ctx(cc);
 907         return 0;
 908
 909 out_destroy_crypt:
 910         kfree(cic->rpages);
 911
 912         for (--i; i >= 0; i--)
 913                 fscrypt_finalize_bounce_page(&cc->cpages[i]);
 914         for (i = 0; i < cc->nr_cpages; i++) {
 915                 if (!cc->cpages[i])
 916                         continue;
 917                 f2fs_put_page(cc->cpages[i], 1);
 918         }
 919 out_put_cic:
 920         kfree(cic);
 921 out_put_dnode:
 922         f2fs_put_dnode(&dn);
 923 out_unlock_op:
 924         f2fs_unlock_op(sbi);
 925         return -EAGAIN;
 926 }
 927
 928 void f2fs_compress_write_end_io(struct bio *bio, struct page *page)
 929 {
 930         struct f2fs_sb_info *sbi = bio->bi_private;
 931         struct compress_io_ctx *cic =
 932                         (struct compress_io_ctx *)page_private(page);
 933         int i;
 934
 935         if (unlikely(bio->bi_status))
 936                 mapping_set_error(cic->inode->i_mapping, -EIO);
 937
 938         f2fs_put_compressed_page(page);
 939
 940         dec_page_count(sbi, F2FS_WB_DATA);
 941
 942         if (refcount_dec_not_one(&cic->ref))
 943                 return;
 944
 945         for (i = 0; i < cic->nr_rpages; i++) {
 946                 WARN_ON(!cic->rpages[i]);
 947                 clear_cold_data(cic->rpages[i]);
 948                 end_page_writeback(cic->rpages[i]);
 949         }
 950
 951         kfree(cic->rpages);
 952         kfree(cic);
 953 }
 954
 955 static int f2fs_write_raw_pages(struct compress_ctx *cc,
 956                                         int *submitted,
 957                                         struct writeback_control *wbc,
 958                                         enum iostat_type io_type)
 959 {
 960         struct address_space *mapping = cc->inode->i_mapping;
 961         int _submitted, compr_blocks, ret;
 962         int i = -1, err = 0;
 963
 964         compr_blocks = f2fs_compressed_blocks(cc);
 965         if (compr_blocks < 0) {
 966                 err = compr_blocks;
 967                 goto out_err;
 968         }
 969
 970         for (i = 0; i < cc->cluster_size; i++) {
 971                 if (!cc->rpages[i])
 972                         continue;
 973 retry_write:
 974                 if (cc->rpages[i]->mapping != mapping) {
 975                         unlock_page(cc->rpages[i]);
 976                         continue;
 977                 }
 978
 979                 BUG_ON(!PageLocked(cc->rpages[i]));
 980
 981                 ret = f2fs_write_single_data_page(cc->rpages[i], &_submitted,
 982                                                 NULL, NULL, wbc, io_type,
 983                                                 compr_blocks);
 984                 if (ret) {
 985                         if (ret == AOP_WRITEPAGE_ACTIVATE) {
 986                                 unlock_page(cc->rpages[i]);
 987                                 ret = 0;
 988                         } else if (ret == -EAGAIN) {
 989                                 ret = 0;
 990                                 cond_resched();
 991                                 congestion_wait(BLK_RW_ASYNC, HZ/50);
 992                                 lock_page(cc->rpages[i]);
 993                                 clear_page_dirty_for_io(cc->rpages[i]);
 994                                 goto retry_write;
 995                         }
 996                         err = ret;
 997                         goto out_fail;
 998                 }
 999
1000                 *submitted += _submitted;
1001         }
1002         return 0;
1003
1004 out_fail:
1005         /* TODO: revoke partially updated block addresses */
1006         BUG_ON(compr_blocks);
1007 out_err:
1008         for (++i; i < cc->cluster_size; i++) {
1009                 if (!cc->rpages[i])
1010                         continue;
1011                 redirty_page_for_writepage(wbc, cc->rpages[i]);
1012                 unlock_page(cc->rpages[i]);
1013         }
1014         return err;
1015 }
1016
1017 int f2fs_write_multi_pages(struct compress_ctx *cc,
1018                                         int *submitted,
1019                                         struct writeback_control *wbc,
1020                                         enum iostat_type io_type)
1021 {
1022         struct f2fs_inode_info *fi = F2FS_I(cc->inode);
1023         const struct f2fs_compress_ops *cops =
1024                         f2fs_cops[fi->i_compress_algorithm];
1025         int err;
1026
1027         *submitted = 0;
1028         if (cluster_may_compress(cc)) {
1029                 err = f2fs_compress_pages(cc);
1030                 if (err == -EAGAIN) {
1031                         goto write;
1032                 } else if (err) {
1033                         f2fs_put_rpages_wbc(cc, wbc, true, 1);
1034                         goto destroy_out;
1035                 }
1036
1037                 err = f2fs_write_compressed_pages(cc, submitted,
1038                                                         wbc, io_type);
1039                 cops->destroy_compress_ctx(cc);
1040                 if (!err)
1041                         return 0;
1042                 f2fs_bug_on(F2FS_I_SB(cc->inode), err != -EAGAIN);
1043         }
1044 write:
1045         f2fs_bug_on(F2FS_I_SB(cc->inode), *submitted);
1046
1047         err = f2fs_write_raw_pages(cc, submitted, wbc, io_type);
1048         f2fs_put_rpages_wbc(cc, wbc, false, 0);
1049 destroy_out:
1050         f2fs_destroy_compress_ctx(cc);
1051         return err;
1052 }
1053
1054 struct decompress_io_ctx *f2fs_alloc_dic(struct compress_ctx *cc)
1055 {
1056         struct f2fs_sb_info *sbi = F2FS_I_SB(cc->inode);
1057         struct decompress_io_ctx *dic;
1058         pgoff_t start_idx = start_idx_of_cluster(cc);
1059         int i;
1060
1061         dic = f2fs_kzalloc(sbi, sizeof(struct decompress_io_ctx), GFP_NOFS);
1062         if (!dic)
1063                 return ERR_PTR(-ENOMEM);
1064
1065         dic->rpages = f2fs_kzalloc(sbi, sizeof(struct page *) <<
1066                         cc->log_cluster_size, GFP_NOFS);
1067         if (!dic->rpages) {
1068                 kfree(dic);
1069                 return ERR_PTR(-ENOMEM);
1070         }
1071
1072         dic->magic = F2FS_COMPRESSED_PAGE_MAGIC;
1073         dic->inode = cc->inode;
1074         refcount_set(&dic->ref, 1);
1075         dic->cluster_idx = cc->cluster_idx;
1076         dic->cluster_size = cc->cluster_size;
1077         dic->log_cluster_size = cc->log_cluster_size;
1078         dic->nr_cpages = cc->nr_cpages;
1079         dic->failed = false;
1080
1081         for (i = 0; i < dic->cluster_size; i++)
1082                 dic->rpages[i] = cc->rpages[i];
1083         dic->nr_rpages = cc->cluster_size;
1084
1085         dic->cpages = f2fs_kzalloc(sbi, sizeof(struct page *) *
1086                                         dic->nr_cpages, GFP_NOFS);
1087         if (!dic->cpages)
1088                 goto out_free;
1089
1090         for (i = 0; i < dic->nr_cpages; i++) {
1091                 struct page *page;
1092
1093                 page = f2fs_grab_page();
1094                 if (!page)
1095                         goto out_free;
1096
1097                 f2fs_set_compressed_page(page, cc->inode,
1098                                         start_idx + i + 1,
1099                                         dic, i ? &dic->ref : NULL);
1100                 dic->cpages[i] = page;
1101         }
1102
1103         dic->tpages = f2fs_kzalloc(sbi, sizeof(struct page *) *
1104                                         dic->cluster_size, GFP_NOFS);
1105         if (!dic->tpages)
1106                 goto out_free;
1107
1108         for (i = 0; i < dic->cluster_size; i++) {
1109                 if (cc->rpages[i])
1110                         continue;
1111
1112                 dic->tpages[i] = f2fs_grab_page();
1113                 if (!dic->tpages[i])
1114                         goto out_free;
1115         }
1116
1117         for (i = 0; i < dic->cluster_size; i++) {
1118                 if (dic->tpages[i])
1119                         continue;
1120                 dic->tpages[i] = cc->rpages[i];
1121         }
1122
1123         return dic;
1124
1125 out_free:
1126         f2fs_free_dic(dic);
1127         return ERR_PTR(-ENOMEM);
1128 }
1129
1130 void f2fs_free_dic(struct decompress_io_ctx *dic)
1131 {
1132         int i;
1133
1134         if (dic->tpages) {
1135                 for (i = 0; i < dic->cluster_size; i++) {
1136                         if (dic->rpages[i])
1137                                 continue;
1138                         unlock_page(dic->tpages[i]);
1139                         put_page(dic->tpages[i]);
1140                 }
1141                 kfree(dic->tpages);
1142         }
1143
1144         if (dic->cpages) {
1145                 for (i = 0; i < dic->nr_cpages; i++) {
1146                         if (!dic->cpages[i])
1147                                 continue;
1148                         f2fs_put_compressed_page(dic->cpages[i]);
1149                 }
1150                 kfree(dic->cpages);
1151         }
1152
1153         kfree(dic->rpages);
1154         kfree(dic);
1155 }
1156
1157 void f2fs_decompress_end_io(struct page **rpages,
1158                         unsigned int cluster_size, bool err, bool verity)
1159 {
1160         int i;
1161
1162         for (i = 0; i < cluster_size; i++) {
1163                 struct page *rpage = rpages[i];
1164
1165                 if (!rpage)
1166                         continue;
1167
1168                 if (err || PageError(rpage)) {
1169                         ClearPageUptodate(rpage);
1170                         ClearPageError(rpage);
1171                 } else {
1172                         if (!verity || fsverity_verify_page(rpage))
1173                                 SetPageUptodate(rpage);
1174                         else
1175                                 SetPageError(rpage);
1176                 }
1177                 unlock_page(rpage);
1178         }
1179 }