Greg Kroah-Hartman | b244131 | 2017-11-01 15:07:57 +0100 | [diff] [blame] | 1 | // SPDX-License-Identifier: GPL-2.0 |
Theodore Ts'o | f64e02f | 2015-04-08 00:00:32 -0400 | [diff] [blame] | 2 | /* |
| 3 | * linux/fs/ext4/readpage.c |
| 4 | * |
| 5 | * Copyright (C) 2002, Linus Torvalds. |
| 6 | * Copyright (C) 2015, Google, Inc. |
| 7 | * |
| 8 | * This was originally taken from fs/mpage.c |
| 9 | * |
Matthew Wilcox (Oracle) | 6311f91f | 2020-06-01 21:47:16 -0700 | [diff] [blame] | 10 | * The ext4_mpage_readpages() function here is intended to |
| 11 | * replace mpage_readahead() in the general case, not just for |
Theodore Ts'o | f64e02f | 2015-04-08 00:00:32 -0400 | [diff] [blame] | 12 | * encrypted files. It has some limitations (see below), where it |
| 13 | * will fall back to read_block_full_page(), but these limitations |
| 14 | * should only be hit when page_size != block_size. |
| 15 | * |
| 16 | * This will allow us to attach a callback function to support ext4 |
| 17 | * encryption. |
| 18 | * |
| 19 | * If anything unusual happens, such as: |
| 20 | * |
| 21 | * - encountering a page which has buffers |
| 22 | * - encountering a page which has a non-hole after a hole |
| 23 | * - encountering a page with non-contiguous blocks |
| 24 | * |
| 25 | * then this code just gives up and calls the buffer_head-based read function. |
| 26 | * It does handle a page which has holes at the end - that is a common case: |
Kirill A. Shutemov | ea1754a | 2016-04-01 15:29:48 +0300 | [diff] [blame] | 27 | * the end-of-file on blocksize < PAGE_SIZE setups. |
Theodore Ts'o | f64e02f | 2015-04-08 00:00:32 -0400 | [diff] [blame] | 28 | * |
| 29 | */ |
| 30 | |
| 31 | #include <linux/kernel.h> |
| 32 | #include <linux/export.h> |
| 33 | #include <linux/mm.h> |
| 34 | #include <linux/kdev_t.h> |
| 35 | #include <linux/gfp.h> |
| 36 | #include <linux/bio.h> |
| 37 | #include <linux/fs.h> |
| 38 | #include <linux/buffer_head.h> |
| 39 | #include <linux/blkdev.h> |
| 40 | #include <linux/highmem.h> |
| 41 | #include <linux/prefetch.h> |
| 42 | #include <linux/mpage.h> |
| 43 | #include <linux/writeback.h> |
| 44 | #include <linux/backing-dev.h> |
| 45 | #include <linux/pagevec.h> |
| 46 | #include <linux/cleancache.h> |
| 47 | |
| 48 | #include "ext4.h" |
| 49 | |
Eric Biggers | 22cfe4b | 2019-07-22 09:26:24 -0700 | [diff] [blame] | 50 | #define NUM_PREALLOC_POST_READ_CTXS 128 |
| 51 | |
| 52 | static struct kmem_cache *bio_post_read_ctx_cache; |
| 53 | static mempool_t *bio_post_read_ctx_pool; |
| 54 | |
| 55 | /* postprocessing steps for read bios */ |
| 56 | enum bio_post_read_step { |
| 57 | STEP_INITIAL = 0, |
| 58 | STEP_DECRYPT, |
| 59 | STEP_VERITY, |
Eric Biggers | 68e4533 | 2019-12-31 12:12:22 -0600 | [diff] [blame] | 60 | STEP_MAX, |
Eric Biggers | 22cfe4b | 2019-07-22 09:26:24 -0700 | [diff] [blame] | 61 | }; |
| 62 | |
| 63 | struct bio_post_read_ctx { |
| 64 | struct bio *bio; |
| 65 | struct work_struct work; |
| 66 | unsigned int cur_step; |
| 67 | unsigned int enabled_steps; |
| 68 | }; |
| 69 | |
| 70 | static void __read_end_io(struct bio *bio) |
Michael Halcrow | c9c7429 | 2015-04-12 00:56:10 -0400 | [diff] [blame] | 71 | { |
Eric Biggers | 22cfe4b | 2019-07-22 09:26:24 -0700 | [diff] [blame] | 72 | struct page *page; |
| 73 | struct bio_vec *bv; |
| 74 | struct bvec_iter_all iter_all; |
| 75 | |
| 76 | bio_for_each_segment_all(bv, bio, iter_all) { |
| 77 | page = bv->bv_page; |
| 78 | |
| 79 | /* PG_error was set if any post_read step failed */ |
| 80 | if (bio->bi_status || PageError(page)) { |
| 81 | ClearPageUptodate(page); |
| 82 | /* will re-read again later */ |
| 83 | ClearPageError(page); |
| 84 | } else { |
| 85 | SetPageUptodate(page); |
| 86 | } |
| 87 | unlock_page(page); |
| 88 | } |
| 89 | if (bio->bi_private) |
| 90 | mempool_free(bio->bi_private, bio_post_read_ctx_pool); |
| 91 | bio_put(bio); |
| 92 | } |
| 93 | |
| 94 | static void bio_post_read_processing(struct bio_post_read_ctx *ctx); |
| 95 | |
| 96 | static void decrypt_work(struct work_struct *work) |
| 97 | { |
| 98 | struct bio_post_read_ctx *ctx = |
| 99 | container_of(work, struct bio_post_read_ctx, work); |
| 100 | |
| 101 | fscrypt_decrypt_bio(ctx->bio); |
| 102 | |
| 103 | bio_post_read_processing(ctx); |
| 104 | } |
| 105 | |
| 106 | static void verity_work(struct work_struct *work) |
| 107 | { |
| 108 | struct bio_post_read_ctx *ctx = |
| 109 | container_of(work, struct bio_post_read_ctx, work); |
Eric Biggers | 68e4533 | 2019-12-31 12:12:22 -0600 | [diff] [blame] | 110 | struct bio *bio = ctx->bio; |
Eric Biggers | 22cfe4b | 2019-07-22 09:26:24 -0700 | [diff] [blame] | 111 | |
Eric Biggers | 68e4533 | 2019-12-31 12:12:22 -0600 | [diff] [blame] | 112 | /* |
| 113 | * fsverity_verify_bio() may call readpages() again, and although verity |
| 114 | * will be disabled for that, decryption may still be needed, causing |
| 115 | * another bio_post_read_ctx to be allocated. So to guarantee that |
| 116 | * mempool_alloc() never deadlocks we must free the current ctx first. |
| 117 | * This is safe because verity is the last post-read step. |
| 118 | */ |
| 119 | BUILD_BUG_ON(STEP_VERITY + 1 != STEP_MAX); |
| 120 | mempool_free(ctx, bio_post_read_ctx_pool); |
| 121 | bio->bi_private = NULL; |
Eric Biggers | 22cfe4b | 2019-07-22 09:26:24 -0700 | [diff] [blame] | 122 | |
Eric Biggers | 68e4533 | 2019-12-31 12:12:22 -0600 | [diff] [blame] | 123 | fsverity_verify_bio(bio); |
| 124 | |
| 125 | __read_end_io(bio); |
Eric Biggers | 22cfe4b | 2019-07-22 09:26:24 -0700 | [diff] [blame] | 126 | } |
| 127 | |
| 128 | static void bio_post_read_processing(struct bio_post_read_ctx *ctx) |
| 129 | { |
| 130 | /* |
| 131 | * We use different work queues for decryption and for verity because |
| 132 | * verity may require reading metadata pages that need decryption, and |
| 133 | * we shouldn't recurse to the same workqueue. |
| 134 | */ |
| 135 | switch (++ctx->cur_step) { |
| 136 | case STEP_DECRYPT: |
| 137 | if (ctx->enabled_steps & (1 << STEP_DECRYPT)) { |
| 138 | INIT_WORK(&ctx->work, decrypt_work); |
| 139 | fscrypt_enqueue_decrypt_work(&ctx->work); |
| 140 | return; |
| 141 | } |
| 142 | ctx->cur_step++; |
Shijie Luo | 70d7ced | 2020-08-10 07:44:35 -0400 | [diff] [blame] | 143 | fallthrough; |
Eric Biggers | 22cfe4b | 2019-07-22 09:26:24 -0700 | [diff] [blame] | 144 | case STEP_VERITY: |
| 145 | if (ctx->enabled_steps & (1 << STEP_VERITY)) { |
| 146 | INIT_WORK(&ctx->work, verity_work); |
| 147 | fsverity_enqueue_verify_work(&ctx->work); |
| 148 | return; |
| 149 | } |
| 150 | ctx->cur_step++; |
Shijie Luo | 70d7ced | 2020-08-10 07:44:35 -0400 | [diff] [blame] | 151 | fallthrough; |
Eric Biggers | 22cfe4b | 2019-07-22 09:26:24 -0700 | [diff] [blame] | 152 | default: |
| 153 | __read_end_io(ctx->bio); |
| 154 | } |
| 155 | } |
| 156 | |
| 157 | static bool bio_post_read_required(struct bio *bio) |
| 158 | { |
| 159 | return bio->bi_private && !bio->bi_status; |
Michael Halcrow | c9c7429 | 2015-04-12 00:56:10 -0400 | [diff] [blame] | 160 | } |
| 161 | |
| 162 | /* |
Theodore Ts'o | f64e02f | 2015-04-08 00:00:32 -0400 | [diff] [blame] | 163 | * I/O completion handler for multipage BIOs. |
| 164 | * |
| 165 | * The mpage code never puts partial pages into a BIO (except for end-of-file). |
| 166 | * If a page does not map to a contiguous run of blocks then it simply falls |
| 167 | * back to block_read_full_page(). |
| 168 | * |
| 169 | * Why is this? If a page's completion depends on a number of different BIOs |
| 170 | * which can complete in any order (or at the same time) then determining the |
| 171 | * status of that page is hard. See end_buffer_async_read() for the details. |
| 172 | * There is no point in duplicating all that complexity. |
| 173 | */ |
Christoph Hellwig | 4246a0b | 2015-07-20 15:29:37 +0200 | [diff] [blame] | 174 | static void mpage_end_io(struct bio *bio) |
Theodore Ts'o | f64e02f | 2015-04-08 00:00:32 -0400 | [diff] [blame] | 175 | { |
Eric Biggers | 22cfe4b | 2019-07-22 09:26:24 -0700 | [diff] [blame] | 176 | if (bio_post_read_required(bio)) { |
| 177 | struct bio_post_read_ctx *ctx = bio->bi_private; |
Theodore Ts'o | f64e02f | 2015-04-08 00:00:32 -0400 | [diff] [blame] | 178 | |
Eric Biggers | 22cfe4b | 2019-07-22 09:26:24 -0700 | [diff] [blame] | 179 | ctx->cur_step = STEP_INITIAL; |
| 180 | bio_post_read_processing(ctx); |
| 181 | return; |
Michael Halcrow | c9c7429 | 2015-04-12 00:56:10 -0400 | [diff] [blame] | 182 | } |
Eric Biggers | 22cfe4b | 2019-07-22 09:26:24 -0700 | [diff] [blame] | 183 | __read_end_io(bio); |
| 184 | } |
Theodore Ts'o | f64e02f | 2015-04-08 00:00:32 -0400 | [diff] [blame] | 185 | |
Eric Biggers | 22cfe4b | 2019-07-22 09:26:24 -0700 | [diff] [blame] | 186 | static inline bool ext4_need_verity(const struct inode *inode, pgoff_t idx) |
| 187 | { |
| 188 | return fsverity_active(inode) && |
| 189 | idx < DIV_ROUND_UP(inode->i_size, PAGE_SIZE); |
| 190 | } |
| 191 | |
Eric Biggers | fd5fe25 | 2019-12-31 12:12:56 -0600 | [diff] [blame] | 192 | static void ext4_set_bio_post_read_ctx(struct bio *bio, |
| 193 | const struct inode *inode, |
| 194 | pgoff_t first_idx) |
Eric Biggers | 22cfe4b | 2019-07-22 09:26:24 -0700 | [diff] [blame] | 195 | { |
| 196 | unsigned int post_read_steps = 0; |
Eric Biggers | 22cfe4b | 2019-07-22 09:26:24 -0700 | [diff] [blame] | 197 | |
Eric Biggers | 4f74d15 | 2020-07-02 01:56:07 +0000 | [diff] [blame] | 198 | if (fscrypt_inode_uses_fs_layer_crypto(inode)) |
Eric Biggers | 22cfe4b | 2019-07-22 09:26:24 -0700 | [diff] [blame] | 199 | post_read_steps |= 1 << STEP_DECRYPT; |
| 200 | |
| 201 | if (ext4_need_verity(inode, first_idx)) |
| 202 | post_read_steps |= 1 << STEP_VERITY; |
| 203 | |
| 204 | if (post_read_steps) { |
Eric Biggers | fd5fe25 | 2019-12-31 12:12:56 -0600 | [diff] [blame] | 205 | /* Due to the mempool, this never fails. */ |
| 206 | struct bio_post_read_ctx *ctx = |
| 207 | mempool_alloc(bio_post_read_ctx_pool, GFP_NOFS); |
| 208 | |
Eric Biggers | 22cfe4b | 2019-07-22 09:26:24 -0700 | [diff] [blame] | 209 | ctx->bio = bio; |
| 210 | ctx->enabled_steps = post_read_steps; |
| 211 | bio->bi_private = ctx; |
Theodore Ts'o | f64e02f | 2015-04-08 00:00:32 -0400 | [diff] [blame] | 212 | } |
Eric Biggers | 22cfe4b | 2019-07-22 09:26:24 -0700 | [diff] [blame] | 213 | } |
Theodore Ts'o | f64e02f | 2015-04-08 00:00:32 -0400 | [diff] [blame] | 214 | |
Eric Biggers | 22cfe4b | 2019-07-22 09:26:24 -0700 | [diff] [blame] | 215 | static inline loff_t ext4_readpage_limit(struct inode *inode) |
| 216 | { |
| 217 | if (IS_ENABLED(CONFIG_FS_VERITY) && |
| 218 | (IS_VERITY(inode) || ext4_verity_in_progress(inode))) |
| 219 | return inode->i_sb->s_maxbytes; |
| 220 | |
| 221 | return i_size_read(inode); |
Theodore Ts'o | f64e02f | 2015-04-08 00:00:32 -0400 | [diff] [blame] | 222 | } |
| 223 | |
Matthew Wilcox (Oracle) | a07f624 | 2020-06-01 21:47:20 -0700 | [diff] [blame] | 224 | int ext4_mpage_readpages(struct inode *inode, |
Matthew Wilcox (Oracle) | 6311f91f | 2020-06-01 21:47:16 -0700 | [diff] [blame] | 225 | struct readahead_control *rac, struct page *page) |
Theodore Ts'o | f64e02f | 2015-04-08 00:00:32 -0400 | [diff] [blame] | 226 | { |
| 227 | struct bio *bio = NULL; |
Theodore Ts'o | f64e02f | 2015-04-08 00:00:32 -0400 | [diff] [blame] | 228 | sector_t last_block_in_bio = 0; |
| 229 | |
Theodore Ts'o | f64e02f | 2015-04-08 00:00:32 -0400 | [diff] [blame] | 230 | const unsigned blkbits = inode->i_blkbits; |
Kirill A. Shutemov | 09cbfea | 2016-04-01 15:29:47 +0300 | [diff] [blame] | 231 | const unsigned blocks_per_page = PAGE_SIZE >> blkbits; |
Theodore Ts'o | f64e02f | 2015-04-08 00:00:32 -0400 | [diff] [blame] | 232 | const unsigned blocksize = 1 << blkbits; |
Eric Biggers | 4f74d15 | 2020-07-02 01:56:07 +0000 | [diff] [blame] | 233 | sector_t next_block; |
Theodore Ts'o | f64e02f | 2015-04-08 00:00:32 -0400 | [diff] [blame] | 234 | sector_t block_in_file; |
| 235 | sector_t last_block; |
| 236 | sector_t last_block_in_file; |
| 237 | sector_t blocks[MAX_BUF_PER_PAGE]; |
| 238 | unsigned page_block; |
| 239 | struct block_device *bdev = inode->i_sb->s_bdev; |
| 240 | int length; |
| 241 | unsigned relative_block = 0; |
| 242 | struct ext4_map_blocks map; |
Matthew Wilcox (Oracle) | 6311f91f | 2020-06-01 21:47:16 -0700 | [diff] [blame] | 243 | unsigned int nr_pages = rac ? readahead_count(rac) : 1; |
Theodore Ts'o | f64e02f | 2015-04-08 00:00:32 -0400 | [diff] [blame] | 244 | |
| 245 | map.m_pblk = 0; |
| 246 | map.m_lblk = 0; |
| 247 | map.m_len = 0; |
| 248 | map.m_flags = 0; |
| 249 | |
yalin wang | de9e918 | 2016-07-05 16:32:32 -0400 | [diff] [blame] | 250 | for (; nr_pages; nr_pages--) { |
Theodore Ts'o | f64e02f | 2015-04-08 00:00:32 -0400 | [diff] [blame] | 251 | int fully_mapped = 1; |
| 252 | unsigned first_hole = blocks_per_page; |
| 253 | |
Matthew Wilcox (Oracle) | 6311f91f | 2020-06-01 21:47:16 -0700 | [diff] [blame] | 254 | if (rac) { |
| 255 | page = readahead_page(rac); |
Liu Xiang | d454a27 | 2019-04-07 11:54:27 -0400 | [diff] [blame] | 256 | prefetchw(&page->flags); |
Theodore Ts'o | f64e02f | 2015-04-08 00:00:32 -0400 | [diff] [blame] | 257 | } |
| 258 | |
| 259 | if (page_has_buffers(page)) |
| 260 | goto confused; |
| 261 | |
Eric Biggers | 4f74d15 | 2020-07-02 01:56:07 +0000 | [diff] [blame] | 262 | block_in_file = next_block = |
| 263 | (sector_t)page->index << (PAGE_SHIFT - blkbits); |
Theodore Ts'o | f64e02f | 2015-04-08 00:00:32 -0400 | [diff] [blame] | 264 | last_block = block_in_file + nr_pages * blocks_per_page; |
Eric Biggers | 22cfe4b | 2019-07-22 09:26:24 -0700 | [diff] [blame] | 265 | last_block_in_file = (ext4_readpage_limit(inode) + |
| 266 | blocksize - 1) >> blkbits; |
Theodore Ts'o | f64e02f | 2015-04-08 00:00:32 -0400 | [diff] [blame] | 267 | if (last_block > last_block_in_file) |
| 268 | last_block = last_block_in_file; |
| 269 | page_block = 0; |
| 270 | |
| 271 | /* |
| 272 | * Map blocks using the previous result first. |
| 273 | */ |
| 274 | if ((map.m_flags & EXT4_MAP_MAPPED) && |
| 275 | block_in_file > map.m_lblk && |
| 276 | block_in_file < (map.m_lblk + map.m_len)) { |
| 277 | unsigned map_offset = block_in_file - map.m_lblk; |
| 278 | unsigned last = map.m_len - map_offset; |
| 279 | |
| 280 | for (relative_block = 0; ; relative_block++) { |
| 281 | if (relative_block == last) { |
| 282 | /* needed? */ |
| 283 | map.m_flags &= ~EXT4_MAP_MAPPED; |
| 284 | break; |
| 285 | } |
| 286 | if (page_block == blocks_per_page) |
| 287 | break; |
| 288 | blocks[page_block] = map.m_pblk + map_offset + |
| 289 | relative_block; |
| 290 | page_block++; |
| 291 | block_in_file++; |
| 292 | } |
| 293 | } |
| 294 | |
| 295 | /* |
| 296 | * Then do more ext4_map_blocks() calls until we are |
| 297 | * done with this page. |
| 298 | */ |
| 299 | while (page_block < blocks_per_page) { |
| 300 | if (block_in_file < last_block) { |
| 301 | map.m_lblk = block_in_file; |
| 302 | map.m_len = last_block - block_in_file; |
| 303 | |
| 304 | if (ext4_map_blocks(NULL, inode, &map, 0) < 0) { |
| 305 | set_error_page: |
| 306 | SetPageError(page); |
| 307 | zero_user_segment(page, 0, |
Kirill A. Shutemov | 09cbfea | 2016-04-01 15:29:47 +0300 | [diff] [blame] | 308 | PAGE_SIZE); |
Theodore Ts'o | f64e02f | 2015-04-08 00:00:32 -0400 | [diff] [blame] | 309 | unlock_page(page); |
| 310 | goto next_page; |
| 311 | } |
| 312 | } |
| 313 | if ((map.m_flags & EXT4_MAP_MAPPED) == 0) { |
| 314 | fully_mapped = 0; |
| 315 | if (first_hole == blocks_per_page) |
| 316 | first_hole = page_block; |
| 317 | page_block++; |
| 318 | block_in_file++; |
| 319 | continue; |
| 320 | } |
| 321 | if (first_hole != blocks_per_page) |
| 322 | goto confused; /* hole -> non-hole */ |
| 323 | |
| 324 | /* Contiguous blocks? */ |
| 325 | if (page_block && blocks[page_block-1] != map.m_pblk-1) |
| 326 | goto confused; |
| 327 | for (relative_block = 0; ; relative_block++) { |
| 328 | if (relative_block == map.m_len) { |
| 329 | /* needed? */ |
| 330 | map.m_flags &= ~EXT4_MAP_MAPPED; |
| 331 | break; |
| 332 | } else if (page_block == blocks_per_page) |
| 333 | break; |
| 334 | blocks[page_block] = map.m_pblk+relative_block; |
| 335 | page_block++; |
| 336 | block_in_file++; |
| 337 | } |
| 338 | } |
| 339 | if (first_hole != blocks_per_page) { |
| 340 | zero_user_segment(page, first_hole << blkbits, |
Kirill A. Shutemov | 09cbfea | 2016-04-01 15:29:47 +0300 | [diff] [blame] | 341 | PAGE_SIZE); |
Theodore Ts'o | f64e02f | 2015-04-08 00:00:32 -0400 | [diff] [blame] | 342 | if (first_hole == 0) { |
Eric Biggers | 22cfe4b | 2019-07-22 09:26:24 -0700 | [diff] [blame] | 343 | if (ext4_need_verity(inode, page->index) && |
| 344 | !fsverity_verify_page(page)) |
| 345 | goto set_error_page; |
Theodore Ts'o | f64e02f | 2015-04-08 00:00:32 -0400 | [diff] [blame] | 346 | SetPageUptodate(page); |
| 347 | unlock_page(page); |
| 348 | goto next_page; |
| 349 | } |
| 350 | } else if (fully_mapped) { |
| 351 | SetPageMappedToDisk(page); |
| 352 | } |
| 353 | if (fully_mapped && blocks_per_page == 1 && |
| 354 | !PageUptodate(page) && cleancache_get_page(page) == 0) { |
| 355 | SetPageUptodate(page); |
| 356 | goto confused; |
| 357 | } |
| 358 | |
| 359 | /* |
| 360 | * This page will go to BIO. Do we need to send this |
| 361 | * BIO off first? |
| 362 | */ |
Eric Biggers | 4f74d15 | 2020-07-02 01:56:07 +0000 | [diff] [blame] | 363 | if (bio && (last_block_in_bio != blocks[0] - 1 || |
| 364 | !fscrypt_mergeable_bio(bio, inode, next_block))) { |
Theodore Ts'o | f64e02f | 2015-04-08 00:00:32 -0400 | [diff] [blame] | 365 | submit_and_realloc: |
Mike Christie | 4e49ea4 | 2016-06-05 14:31:41 -0500 | [diff] [blame] | 366 | submit_bio(bio); |
Theodore Ts'o | f64e02f | 2015-04-08 00:00:32 -0400 | [diff] [blame] | 367 | bio = NULL; |
| 368 | } |
| 369 | if (bio == NULL) { |
Gao Xiang | 5500221 | 2019-10-31 17:23:15 +0800 | [diff] [blame] | 370 | /* |
| 371 | * bio_alloc will _always_ be able to allocate a bio if |
| 372 | * __GFP_DIRECT_RECLAIM is set, see bio_alloc_bioset(). |
| 373 | */ |
Matthew Wilcox (Oracle) | 5f7136d | 2021-01-29 04:38:57 +0000 | [diff] [blame] | 374 | bio = bio_alloc(GFP_KERNEL, bio_max_segs(nr_pages)); |
Eric Biggers | 4f74d15 | 2020-07-02 01:56:07 +0000 | [diff] [blame] | 375 | fscrypt_set_bio_crypt_ctx(bio, inode, next_block, |
| 376 | GFP_KERNEL); |
Eric Biggers | fd5fe25 | 2019-12-31 12:12:56 -0600 | [diff] [blame] | 377 | ext4_set_bio_post_read_ctx(bio, inode, page->index); |
Christoph Hellwig | 74d4699 | 2017-08-23 19:10:32 +0200 | [diff] [blame] | 378 | bio_set_dev(bio, bdev); |
Theodore Ts'o | f64e02f | 2015-04-08 00:00:32 -0400 | [diff] [blame] | 379 | bio->bi_iter.bi_sector = blocks[0] << (blkbits - 9); |
| 380 | bio->bi_end_io = mpage_end_io; |
Jens Axboe | ac22b46 | 2018-08-17 15:45:42 -0700 | [diff] [blame] | 381 | bio_set_op_attrs(bio, REQ_OP_READ, |
Matthew Wilcox (Oracle) | 6311f91f | 2020-06-01 21:47:16 -0700 | [diff] [blame] | 382 | rac ? REQ_RAHEAD : 0); |
Theodore Ts'o | f64e02f | 2015-04-08 00:00:32 -0400 | [diff] [blame] | 383 | } |
| 384 | |
| 385 | length = first_hole << blkbits; |
| 386 | if (bio_add_page(bio, page, length, 0) < length) |
| 387 | goto submit_and_realloc; |
| 388 | |
| 389 | if (((map.m_flags & EXT4_MAP_BOUNDARY) && |
| 390 | (relative_block == map.m_len)) || |
| 391 | (first_hole != blocks_per_page)) { |
Mike Christie | 4e49ea4 | 2016-06-05 14:31:41 -0500 | [diff] [blame] | 392 | submit_bio(bio); |
Theodore Ts'o | f64e02f | 2015-04-08 00:00:32 -0400 | [diff] [blame] | 393 | bio = NULL; |
| 394 | } else |
| 395 | last_block_in_bio = blocks[blocks_per_page - 1]; |
| 396 | goto next_page; |
| 397 | confused: |
| 398 | if (bio) { |
Mike Christie | 4e49ea4 | 2016-06-05 14:31:41 -0500 | [diff] [blame] | 399 | submit_bio(bio); |
Theodore Ts'o | f64e02f | 2015-04-08 00:00:32 -0400 | [diff] [blame] | 400 | bio = NULL; |
| 401 | } |
| 402 | if (!PageUptodate(page)) |
| 403 | block_read_full_page(page, ext4_get_block); |
| 404 | else |
| 405 | unlock_page(page); |
| 406 | next_page: |
Matthew Wilcox (Oracle) | 6311f91f | 2020-06-01 21:47:16 -0700 | [diff] [blame] | 407 | if (rac) |
Kirill A. Shutemov | 09cbfea | 2016-04-01 15:29:47 +0300 | [diff] [blame] | 408 | put_page(page); |
Theodore Ts'o | f64e02f | 2015-04-08 00:00:32 -0400 | [diff] [blame] | 409 | } |
Theodore Ts'o | f64e02f | 2015-04-08 00:00:32 -0400 | [diff] [blame] | 410 | if (bio) |
Mike Christie | 4e49ea4 | 2016-06-05 14:31:41 -0500 | [diff] [blame] | 411 | submit_bio(bio); |
Theodore Ts'o | f64e02f | 2015-04-08 00:00:32 -0400 | [diff] [blame] | 412 | return 0; |
| 413 | } |
Eric Biggers | 22cfe4b | 2019-07-22 09:26:24 -0700 | [diff] [blame] | 414 | |
| 415 | int __init ext4_init_post_read_processing(void) |
| 416 | { |
| 417 | bio_post_read_ctx_cache = |
| 418 | kmem_cache_create("ext4_bio_post_read_ctx", |
| 419 | sizeof(struct bio_post_read_ctx), 0, 0, NULL); |
| 420 | if (!bio_post_read_ctx_cache) |
| 421 | goto fail; |
| 422 | bio_post_read_ctx_pool = |
| 423 | mempool_create_slab_pool(NUM_PREALLOC_POST_READ_CTXS, |
| 424 | bio_post_read_ctx_cache); |
| 425 | if (!bio_post_read_ctx_pool) |
| 426 | goto fail_free_cache; |
| 427 | return 0; |
| 428 | |
| 429 | fail_free_cache: |
| 430 | kmem_cache_destroy(bio_post_read_ctx_cache); |
| 431 | fail: |
| 432 | return -ENOMEM; |
| 433 | } |
| 434 | |
| 435 | void ext4_exit_post_read_processing(void) |
| 436 | { |
| 437 | mempool_destroy(bio_post_read_ctx_pool); |
| 438 | kmem_cache_destroy(bio_post_read_ctx_cache); |
| 439 | } |