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/moduleparam.h>
11 #include <linux/writeback.h>
12 #include <linux/backing-dev.h>
13 #include <linux/lzo.h>
14 #include <linux/lz4.h>
15 #include <linux/zstd.h>
16 #include <linux/pagevec.h>
17 
18 #include "f2fs.h"
19 #include "node.h"
20 #include "segment.h"
21 #include <trace/events/f2fs.h>
22 
23 static struct kmem_cache *cic_entry_slab;
24 static struct kmem_cache *dic_entry_slab;
25 
page_array_alloc(struct inode * inode,int nr)26 static void *page_array_alloc(struct inode *inode, int nr)
27 {
28 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
29 	unsigned int size = sizeof(struct page *) * nr;
30 
31 	if (likely(size <= sbi->page_array_slab_size))
32 		return f2fs_kmem_cache_alloc(sbi->page_array_slab,
33 					GFP_F2FS_ZERO, false, F2FS_I_SB(inode));
34 	return f2fs_kzalloc(sbi, size, GFP_NOFS);
35 }
36 
page_array_free(struct inode * inode,void * pages,int nr)37 static void page_array_free(struct inode *inode, void *pages, int nr)
38 {
39 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
40 	unsigned int size = sizeof(struct page *) * nr;
41 
42 	if (!pages)
43 		return;
44 
45 	if (likely(size <= sbi->page_array_slab_size))
46 		kmem_cache_free(sbi->page_array_slab, pages);
47 	else
48 		kfree(pages);
49 }
50 
51 struct f2fs_compress_ops {
52 	int (*init_compress_ctx)(struct compress_ctx *cc);
53 	void (*destroy_compress_ctx)(struct compress_ctx *cc);
54 	int (*compress_pages)(struct compress_ctx *cc);
55 	int (*init_decompress_ctx)(struct decompress_io_ctx *dic);
56 	void (*destroy_decompress_ctx)(struct decompress_io_ctx *dic);
57 	int (*decompress_pages)(struct decompress_io_ctx *dic);
58 };
59 
offset_in_cluster(struct compress_ctx * cc,pgoff_t index)60 static unsigned int offset_in_cluster(struct compress_ctx *cc, pgoff_t index)
61 {
62 	return index & (cc->cluster_size - 1);
63 }
64 
cluster_idx(struct compress_ctx * cc,pgoff_t index)65 static pgoff_t cluster_idx(struct compress_ctx *cc, pgoff_t index)
66 {
67 	return index >> cc->log_cluster_size;
68 }
69 
start_idx_of_cluster(struct compress_ctx * cc)70 static pgoff_t start_idx_of_cluster(struct compress_ctx *cc)
71 {
72 	return cc->cluster_idx << cc->log_cluster_size;
73 }
74 
f2fs_is_compressed_page(struct page * page)75 bool f2fs_is_compressed_page(struct page *page)
76 {
77 	if (!PagePrivate(page))
78 		return false;
79 	if (!page_private(page))
80 		return false;
81 	if (page_private_nonpointer(page))
82 		return false;
83 
84 	f2fs_bug_on(F2FS_M_SB(page->mapping),
85 		*((u32 *)page_private(page)) != F2FS_COMPRESSED_PAGE_MAGIC);
86 	return true;
87 }
88 
f2fs_set_compressed_page(struct page * page,struct inode * inode,pgoff_t index,void * data)89 static void f2fs_set_compressed_page(struct page *page,
90 		struct inode *inode, pgoff_t index, void *data)
91 {
92 	attach_page_private(page, (void *)data);
93 
94 	/* i_crypto_info and iv index */
95 	page->index = index;
96 	page->mapping = inode->i_mapping;
97 }
98 
f2fs_drop_rpages(struct compress_ctx * cc,int len,bool unlock)99 static void f2fs_drop_rpages(struct compress_ctx *cc, int len, bool unlock)
100 {
101 	int i;
102 
103 	for (i = 0; i < len; i++) {
104 		if (!cc->rpages[i])
105 			continue;
106 		if (unlock)
107 			unlock_page(cc->rpages[i]);
108 		else
109 			put_page(cc->rpages[i]);
110 	}
111 }
112 
f2fs_put_rpages(struct compress_ctx * cc)113 static void f2fs_put_rpages(struct compress_ctx *cc)
114 {
115 	f2fs_drop_rpages(cc, cc->cluster_size, false);
116 }
117 
f2fs_unlock_rpages(struct compress_ctx * cc,int len)118 static void f2fs_unlock_rpages(struct compress_ctx *cc, int len)
119 {
120 	f2fs_drop_rpages(cc, len, true);
121 }
122 
f2fs_put_rpages_wbc(struct compress_ctx * cc,struct writeback_control * wbc,bool redirty,int unlock)123 static void f2fs_put_rpages_wbc(struct compress_ctx *cc,
124 		struct writeback_control *wbc, bool redirty, int unlock)
125 {
126 	unsigned int i;
127 
128 	for (i = 0; i < cc->cluster_size; i++) {
129 		if (!cc->rpages[i])
130 			continue;
131 		if (redirty)
132 			redirty_page_for_writepage(wbc, cc->rpages[i]);
133 		f2fs_put_page(cc->rpages[i], unlock);
134 	}
135 }
136 
f2fs_compress_control_page(struct page * page)137 struct page *f2fs_compress_control_page(struct page *page)
138 {
139 	return ((struct compress_io_ctx *)page_private(page))->rpages[0];
140 }
141 
f2fs_init_compress_ctx(struct compress_ctx * cc)142 int f2fs_init_compress_ctx(struct compress_ctx *cc)
143 {
144 	if (cc->rpages)
145 		return 0;
146 
147 	cc->rpages = page_array_alloc(cc->inode, cc->cluster_size);
148 	return cc->rpages ? 0 : -ENOMEM;
149 }
150 
f2fs_destroy_compress_ctx(struct compress_ctx * cc,bool reuse)151 void f2fs_destroy_compress_ctx(struct compress_ctx *cc, bool reuse)
152 {
153 	page_array_free(cc->inode, cc->rpages, cc->cluster_size);
154 	cc->rpages = NULL;
155 	cc->nr_rpages = 0;
156 	cc->nr_cpages = 0;
157 	cc->valid_nr_cpages = 0;
158 	if (!reuse)
159 		cc->cluster_idx = NULL_CLUSTER;
160 }
161 
f2fs_compress_ctx_add_page(struct compress_ctx * cc,struct page * page)162 void f2fs_compress_ctx_add_page(struct compress_ctx *cc, struct page *page)
163 {
164 	unsigned int cluster_ofs;
165 
166 	if (!f2fs_cluster_can_merge_page(cc, page->index))
167 		f2fs_bug_on(F2FS_I_SB(cc->inode), 1);
168 
169 	cluster_ofs = offset_in_cluster(cc, page->index);
170 	cc->rpages[cluster_ofs] = page;
171 	cc->nr_rpages++;
172 	cc->cluster_idx = cluster_idx(cc, page->index);
173 }
174 
175 #ifdef CONFIG_F2FS_FS_LZO
lzo_init_compress_ctx(struct compress_ctx * cc)176 static int lzo_init_compress_ctx(struct compress_ctx *cc)
177 {
178 	cc->private = f2fs_kvmalloc(F2FS_I_SB(cc->inode),
179 				LZO1X_MEM_COMPRESS, GFP_NOFS);
180 	if (!cc->private)
181 		return -ENOMEM;
182 
183 	cc->clen = lzo1x_worst_compress(PAGE_SIZE << cc->log_cluster_size);
184 	return 0;
185 }
186 
lzo_destroy_compress_ctx(struct compress_ctx * cc)187 static void lzo_destroy_compress_ctx(struct compress_ctx *cc)
188 {
189 	kvfree(cc->private);
190 	cc->private = NULL;
191 }
192 
lzo_compress_pages(struct compress_ctx * cc)193 static int lzo_compress_pages(struct compress_ctx *cc)
194 {
195 	int ret;
196 
197 	ret = lzo1x_1_compress(cc->rbuf, cc->rlen, cc->cbuf->cdata,
198 					&cc->clen, cc->private);
199 	if (ret != LZO_E_OK) {
200 		printk_ratelimited("%sF2FS-fs (%s): lzo compress failed, ret:%d\n",
201 				KERN_ERR, F2FS_I_SB(cc->inode)->sb->s_id, ret);
202 		return -EIO;
203 	}
204 	return 0;
205 }
206 
lzo_decompress_pages(struct decompress_io_ctx * dic)207 static int lzo_decompress_pages(struct decompress_io_ctx *dic)
208 {
209 	int ret;
210 
211 	ret = lzo1x_decompress_safe(dic->cbuf->cdata, dic->clen,
212 						dic->rbuf, &dic->rlen);
213 	if (ret != LZO_E_OK) {
214 		printk_ratelimited("%sF2FS-fs (%s): lzo decompress failed, ret:%d\n",
215 				KERN_ERR, F2FS_I_SB(dic->inode)->sb->s_id, ret);
216 		return -EIO;
217 	}
218 
219 	if (dic->rlen != PAGE_SIZE << dic->log_cluster_size) {
220 		printk_ratelimited("%sF2FS-fs (%s): lzo invalid rlen:%zu, "
221 					"expected:%lu\n", KERN_ERR,
222 					F2FS_I_SB(dic->inode)->sb->s_id,
223 					dic->rlen,
224 					PAGE_SIZE << dic->log_cluster_size);
225 		return -EIO;
226 	}
227 	return 0;
228 }
229 
230 static const struct f2fs_compress_ops f2fs_lzo_ops = {
231 	.init_compress_ctx	= lzo_init_compress_ctx,
232 	.destroy_compress_ctx	= lzo_destroy_compress_ctx,
233 	.compress_pages		= lzo_compress_pages,
234 	.decompress_pages	= lzo_decompress_pages,
235 };
236 #endif
237 
238 #ifdef CONFIG_F2FS_FS_LZ4
lz4_init_compress_ctx(struct compress_ctx * cc)239 static int lz4_init_compress_ctx(struct compress_ctx *cc)
240 {
241 	unsigned int size = LZ4_MEM_COMPRESS;
242 
243 #ifdef CONFIG_F2FS_FS_LZ4HC
244 	if (F2FS_I(cc->inode)->i_compress_flag >> COMPRESS_LEVEL_OFFSET)
245 		size = LZ4HC_MEM_COMPRESS;
246 #endif
247 
248 	cc->private = f2fs_kvmalloc(F2FS_I_SB(cc->inode), size, GFP_NOFS);
249 	if (!cc->private)
250 		return -ENOMEM;
251 
252 	/*
253 	 * we do not change cc->clen to LZ4_compressBound(inputsize) to
254 	 * adapt worst compress case, because lz4 compressor can handle
255 	 * output budget properly.
256 	 */
257 	cc->clen = cc->rlen - PAGE_SIZE - COMPRESS_HEADER_SIZE;
258 	return 0;
259 }
260 
lz4_destroy_compress_ctx(struct compress_ctx * cc)261 static void lz4_destroy_compress_ctx(struct compress_ctx *cc)
262 {
263 	kvfree(cc->private);
264 	cc->private = NULL;
265 }
266 
267 #ifdef CONFIG_F2FS_FS_LZ4HC
lz4hc_compress_pages(struct compress_ctx * cc)268 static int lz4hc_compress_pages(struct compress_ctx *cc)
269 {
270 	unsigned char level = F2FS_I(cc->inode)->i_compress_flag >>
271 						COMPRESS_LEVEL_OFFSET;
272 	int len;
273 
274 	if (level)
275 		len = LZ4_compress_HC(cc->rbuf, cc->cbuf->cdata, cc->rlen,
276 					cc->clen, level, cc->private);
277 	else
278 		len = LZ4_compress_default(cc->rbuf, cc->cbuf->cdata, cc->rlen,
279 						cc->clen, cc->private);
280 	if (!len)
281 		return -EAGAIN;
282 
283 	cc->clen = len;
284 	return 0;
285 }
286 #endif
287 
lz4_compress_pages(struct compress_ctx * cc)288 static int lz4_compress_pages(struct compress_ctx *cc)
289 {
290 	int len;
291 
292 #ifdef CONFIG_F2FS_FS_LZ4HC
293 	return lz4hc_compress_pages(cc);
294 #endif
295 	len = LZ4_compress_default(cc->rbuf, cc->cbuf->cdata, cc->rlen,
296 						cc->clen, cc->private);
297 	if (!len)
298 		return -EAGAIN;
299 
300 	cc->clen = len;
301 	return 0;
302 }
303 
lz4_decompress_pages(struct decompress_io_ctx * dic)304 static int lz4_decompress_pages(struct decompress_io_ctx *dic)
305 {
306 	int ret;
307 
308 	ret = LZ4_decompress_safe(dic->cbuf->cdata, dic->rbuf,
309 						dic->clen, dic->rlen);
310 	if (ret < 0) {
311 		printk_ratelimited("%sF2FS-fs (%s): lz4 decompress failed, ret:%d\n",
312 				KERN_ERR, F2FS_I_SB(dic->inode)->sb->s_id, ret);
313 		return -EIO;
314 	}
315 
316 	if (ret != PAGE_SIZE << dic->log_cluster_size) {
317 		printk_ratelimited("%sF2FS-fs (%s): lz4 invalid ret:%d, "
318 					"expected:%lu\n", KERN_ERR,
319 					F2FS_I_SB(dic->inode)->sb->s_id, ret,
320 					PAGE_SIZE << dic->log_cluster_size);
321 		return -EIO;
322 	}
323 	return 0;
324 }
325 
326 static const struct f2fs_compress_ops f2fs_lz4_ops = {
327 	.init_compress_ctx	= lz4_init_compress_ctx,
328 	.destroy_compress_ctx	= lz4_destroy_compress_ctx,
329 	.compress_pages		= lz4_compress_pages,
330 	.decompress_pages	= lz4_decompress_pages,
331 };
332 #endif
333 
334 #ifdef CONFIG_F2FS_FS_ZSTD
335 #define F2FS_ZSTD_DEFAULT_CLEVEL	1
336 
zstd_init_compress_ctx(struct compress_ctx * cc)337 static int zstd_init_compress_ctx(struct compress_ctx *cc)
338 {
339 	zstd_parameters params;
340 	zstd_cstream *stream;
341 	void *workspace;
342 	unsigned int workspace_size;
343 	unsigned char level = F2FS_I(cc->inode)->i_compress_flag >>
344 						COMPRESS_LEVEL_OFFSET;
345 
346 	if (!level)
347 		level = F2FS_ZSTD_DEFAULT_CLEVEL;
348 
349 	params = zstd_get_params(level, cc->rlen);
350 	workspace_size = zstd_cstream_workspace_bound(&params.cParams);
351 
352 	workspace = f2fs_kvmalloc(F2FS_I_SB(cc->inode),
353 					workspace_size, GFP_NOFS);
354 	if (!workspace)
355 		return -ENOMEM;
356 
357 	stream = zstd_init_cstream(&params, 0, workspace, workspace_size);
358 	if (!stream) {
359 		printk_ratelimited("%sF2FS-fs (%s): %s zstd_init_cstream failed\n",
360 				KERN_ERR, F2FS_I_SB(cc->inode)->sb->s_id,
361 				__func__);
362 		kvfree(workspace);
363 		return -EIO;
364 	}
365 
366 	cc->private = workspace;
367 	cc->private2 = stream;
368 
369 	cc->clen = cc->rlen - PAGE_SIZE - COMPRESS_HEADER_SIZE;
370 	return 0;
371 }
372 
zstd_destroy_compress_ctx(struct compress_ctx * cc)373 static void zstd_destroy_compress_ctx(struct compress_ctx *cc)
374 {
375 	kvfree(cc->private);
376 	cc->private = NULL;
377 	cc->private2 = NULL;
378 }
379 
zstd_compress_pages(struct compress_ctx * cc)380 static int zstd_compress_pages(struct compress_ctx *cc)
381 {
382 	zstd_cstream *stream = cc->private2;
383 	zstd_in_buffer inbuf;
384 	zstd_out_buffer outbuf;
385 	int src_size = cc->rlen;
386 	int dst_size = src_size - PAGE_SIZE - COMPRESS_HEADER_SIZE;
387 	int ret;
388 
389 	inbuf.pos = 0;
390 	inbuf.src = cc->rbuf;
391 	inbuf.size = src_size;
392 
393 	outbuf.pos = 0;
394 	outbuf.dst = cc->cbuf->cdata;
395 	outbuf.size = dst_size;
396 
397 	ret = zstd_compress_stream(stream, &outbuf, &inbuf);
398 	if (zstd_is_error(ret)) {
399 		printk_ratelimited("%sF2FS-fs (%s): %s zstd_compress_stream failed, ret: %d\n",
400 				KERN_ERR, F2FS_I_SB(cc->inode)->sb->s_id,
401 				__func__, zstd_get_error_code(ret));
402 		return -EIO;
403 	}
404 
405 	ret = zstd_end_stream(stream, &outbuf);
406 	if (zstd_is_error(ret)) {
407 		printk_ratelimited("%sF2FS-fs (%s): %s zstd_end_stream returned %d\n",
408 				KERN_ERR, F2FS_I_SB(cc->inode)->sb->s_id,
409 				__func__, zstd_get_error_code(ret));
410 		return -EIO;
411 	}
412 
413 	/*
414 	 * there is compressed data remained in intermediate buffer due to
415 	 * no more space in cbuf.cdata
416 	 */
417 	if (ret)
418 		return -EAGAIN;
419 
420 	cc->clen = outbuf.pos;
421 	return 0;
422 }
423 
zstd_init_decompress_ctx(struct decompress_io_ctx * dic)424 static int zstd_init_decompress_ctx(struct decompress_io_ctx *dic)
425 {
426 	zstd_dstream *stream;
427 	void *workspace;
428 	unsigned int workspace_size;
429 	unsigned int max_window_size =
430 			MAX_COMPRESS_WINDOW_SIZE(dic->log_cluster_size);
431 
432 	workspace_size = zstd_dstream_workspace_bound(max_window_size);
433 
434 	workspace = f2fs_kvmalloc(F2FS_I_SB(dic->inode),
435 					workspace_size, GFP_NOFS);
436 	if (!workspace)
437 		return -ENOMEM;
438 
439 	stream = zstd_init_dstream(max_window_size, workspace, workspace_size);
440 	if (!stream) {
441 		printk_ratelimited("%sF2FS-fs (%s): %s zstd_init_dstream failed\n",
442 				KERN_ERR, F2FS_I_SB(dic->inode)->sb->s_id,
443 				__func__);
444 		kvfree(workspace);
445 		return -EIO;
446 	}
447 
448 	dic->private = workspace;
449 	dic->private2 = stream;
450 
451 	return 0;
452 }
453 
zstd_destroy_decompress_ctx(struct decompress_io_ctx * dic)454 static void zstd_destroy_decompress_ctx(struct decompress_io_ctx *dic)
455 {
456 	kvfree(dic->private);
457 	dic->private = NULL;
458 	dic->private2 = NULL;
459 }
460 
zstd_decompress_pages(struct decompress_io_ctx * dic)461 static int zstd_decompress_pages(struct decompress_io_ctx *dic)
462 {
463 	zstd_dstream *stream = dic->private2;
464 	zstd_in_buffer inbuf;
465 	zstd_out_buffer outbuf;
466 	int ret;
467 
468 	inbuf.pos = 0;
469 	inbuf.src = dic->cbuf->cdata;
470 	inbuf.size = dic->clen;
471 
472 	outbuf.pos = 0;
473 	outbuf.dst = dic->rbuf;
474 	outbuf.size = dic->rlen;
475 
476 	ret = zstd_decompress_stream(stream, &outbuf, &inbuf);
477 	if (zstd_is_error(ret)) {
478 		printk_ratelimited("%sF2FS-fs (%s): %s zstd_decompress_stream failed, ret: %d\n",
479 				KERN_ERR, F2FS_I_SB(dic->inode)->sb->s_id,
480 				__func__, zstd_get_error_code(ret));
481 		return -EIO;
482 	}
483 
484 	if (dic->rlen != outbuf.pos) {
485 		printk_ratelimited("%sF2FS-fs (%s): %s ZSTD invalid rlen:%zu, "
486 				"expected:%lu\n", KERN_ERR,
487 				F2FS_I_SB(dic->inode)->sb->s_id,
488 				__func__, dic->rlen,
489 				PAGE_SIZE << dic->log_cluster_size);
490 		return -EIO;
491 	}
492 
493 	return 0;
494 }
495 
496 static const struct f2fs_compress_ops f2fs_zstd_ops = {
497 	.init_compress_ctx	= zstd_init_compress_ctx,
498 	.destroy_compress_ctx	= zstd_destroy_compress_ctx,
499 	.compress_pages		= zstd_compress_pages,
500 	.init_decompress_ctx	= zstd_init_decompress_ctx,
501 	.destroy_decompress_ctx	= zstd_destroy_decompress_ctx,
502 	.decompress_pages	= zstd_decompress_pages,
503 };
504 #endif
505 
506 #ifdef CONFIG_F2FS_FS_LZO
507 #ifdef CONFIG_F2FS_FS_LZORLE
lzorle_compress_pages(struct compress_ctx * cc)508 static int lzorle_compress_pages(struct compress_ctx *cc)
509 {
510 	int ret;
511 
512 	ret = lzorle1x_1_compress(cc->rbuf, cc->rlen, cc->cbuf->cdata,
513 					&cc->clen, cc->private);
514 	if (ret != LZO_E_OK) {
515 		printk_ratelimited("%sF2FS-fs (%s): lzo-rle compress failed, ret:%d\n",
516 				KERN_ERR, F2FS_I_SB(cc->inode)->sb->s_id, ret);
517 		return -EIO;
518 	}
519 	return 0;
520 }
521 
522 static const struct f2fs_compress_ops f2fs_lzorle_ops = {
523 	.init_compress_ctx	= lzo_init_compress_ctx,
524 	.destroy_compress_ctx	= lzo_destroy_compress_ctx,
525 	.compress_pages		= lzorle_compress_pages,
526 	.decompress_pages	= lzo_decompress_pages,
527 };
528 #endif
529 #endif
530 
531 static const struct f2fs_compress_ops *f2fs_cops[COMPRESS_MAX] = {
532 #ifdef CONFIG_F2FS_FS_LZO
533 	&f2fs_lzo_ops,
534 #else
535 	NULL,
536 #endif
537 #ifdef CONFIG_F2FS_FS_LZ4
538 	&f2fs_lz4_ops,
539 #else
540 	NULL,
541 #endif
542 #ifdef CONFIG_F2FS_FS_ZSTD
543 	&f2fs_zstd_ops,
544 #else
545 	NULL,
546 #endif
547 #if defined(CONFIG_F2FS_FS_LZO) && defined(CONFIG_F2FS_FS_LZORLE)
548 	&f2fs_lzorle_ops,
549 #else
550 	NULL,
551 #endif
552 };
553 
f2fs_is_compress_backend_ready(struct inode * inode)554 bool f2fs_is_compress_backend_ready(struct inode *inode)
555 {
556 	if (!f2fs_compressed_file(inode))
557 		return true;
558 	return f2fs_cops[F2FS_I(inode)->i_compress_algorithm];
559 }
560 
561 static mempool_t *compress_page_pool;
562 static int num_compress_pages = 512;
563 module_param(num_compress_pages, uint, 0444);
564 MODULE_PARM_DESC(num_compress_pages,
565 		"Number of intermediate compress pages to preallocate");
566 
f2fs_init_compress_mempool(void)567 int f2fs_init_compress_mempool(void)
568 {
569 	compress_page_pool = mempool_create_page_pool(num_compress_pages, 0);
570 	if (!compress_page_pool)
571 		return -ENOMEM;
572 
573 	return 0;
574 }
575 
f2fs_destroy_compress_mempool(void)576 void f2fs_destroy_compress_mempool(void)
577 {
578 	mempool_destroy(compress_page_pool);
579 }
580 
f2fs_compress_alloc_page(void)581 static struct page *f2fs_compress_alloc_page(void)
582 {
583 	struct page *page;
584 
585 	page = mempool_alloc(compress_page_pool, GFP_NOFS);
586 	lock_page(page);
587 
588 	return page;
589 }
590 
f2fs_compress_free_page(struct page * page)591 static void f2fs_compress_free_page(struct page *page)
592 {
593 	if (!page)
594 		return;
595 	detach_page_private(page);
596 	page->mapping = NULL;
597 	unlock_page(page);
598 	mempool_free(page, compress_page_pool);
599 }
600 
601 #define MAX_VMAP_RETRIES	3
602 
f2fs_vmap(struct page ** pages,unsigned int count)603 static void *f2fs_vmap(struct page **pages, unsigned int count)
604 {
605 	int i;
606 	void *buf = NULL;
607 
608 	for (i = 0; i < MAX_VMAP_RETRIES; i++) {
609 		buf = vm_map_ram(pages, count, -1);
610 		if (buf)
611 			break;
612 		vm_unmap_aliases();
613 	}
614 	return buf;
615 }
616 
f2fs_compress_pages(struct compress_ctx * cc)617 static int f2fs_compress_pages(struct compress_ctx *cc)
618 {
619 	struct f2fs_inode_info *fi = F2FS_I(cc->inode);
620 	const struct f2fs_compress_ops *cops =
621 				f2fs_cops[fi->i_compress_algorithm];
622 	unsigned int max_len, new_nr_cpages;
623 	u32 chksum = 0;
624 	int i, ret;
625 
626 	trace_f2fs_compress_pages_start(cc->inode, cc->cluster_idx,
627 				cc->cluster_size, fi->i_compress_algorithm);
628 
629 	if (cops->init_compress_ctx) {
630 		ret = cops->init_compress_ctx(cc);
631 		if (ret)
632 			goto out;
633 	}
634 
635 	max_len = COMPRESS_HEADER_SIZE + cc->clen;
636 	cc->nr_cpages = DIV_ROUND_UP(max_len, PAGE_SIZE);
637 	cc->valid_nr_cpages = cc->nr_cpages;
638 
639 	cc->cpages = page_array_alloc(cc->inode, cc->nr_cpages);
640 	if (!cc->cpages) {
641 		ret = -ENOMEM;
642 		goto destroy_compress_ctx;
643 	}
644 
645 	for (i = 0; i < cc->nr_cpages; i++) {
646 		cc->cpages[i] = f2fs_compress_alloc_page();
647 		if (!cc->cpages[i]) {
648 			ret = -ENOMEM;
649 			goto out_free_cpages;
650 		}
651 	}
652 
653 	cc->rbuf = f2fs_vmap(cc->rpages, cc->cluster_size);
654 	if (!cc->rbuf) {
655 		ret = -ENOMEM;
656 		goto out_free_cpages;
657 	}
658 
659 	cc->cbuf = f2fs_vmap(cc->cpages, cc->nr_cpages);
660 	if (!cc->cbuf) {
661 		ret = -ENOMEM;
662 		goto out_vunmap_rbuf;
663 	}
664 
665 	ret = cops->compress_pages(cc);
666 	if (ret)
667 		goto out_vunmap_cbuf;
668 
669 	max_len = PAGE_SIZE * (cc->cluster_size - 1) - COMPRESS_HEADER_SIZE;
670 
671 	if (cc->clen > max_len) {
672 		ret = -EAGAIN;
673 		goto out_vunmap_cbuf;
674 	}
675 
676 	cc->cbuf->clen = cpu_to_le32(cc->clen);
677 
678 	if (fi->i_compress_flag & 1 << COMPRESS_CHKSUM)
679 		chksum = f2fs_crc32(F2FS_I_SB(cc->inode),
680 					cc->cbuf->cdata, cc->clen);
681 	cc->cbuf->chksum = cpu_to_le32(chksum);
682 
683 	for (i = 0; i < COMPRESS_DATA_RESERVED_SIZE; i++)
684 		cc->cbuf->reserved[i] = cpu_to_le32(0);
685 
686 	new_nr_cpages = DIV_ROUND_UP(cc->clen + COMPRESS_HEADER_SIZE, PAGE_SIZE);
687 
688 	/* zero out any unused part of the last page */
689 	memset(&cc->cbuf->cdata[cc->clen], 0,
690 			(new_nr_cpages * PAGE_SIZE) -
691 			(cc->clen + COMPRESS_HEADER_SIZE));
692 
693 	vm_unmap_ram(cc->cbuf, cc->nr_cpages);
694 	vm_unmap_ram(cc->rbuf, cc->cluster_size);
695 
696 	for (i = 0; i < cc->nr_cpages; i++) {
697 		if (i < new_nr_cpages)
698 			continue;
699 		f2fs_compress_free_page(cc->cpages[i]);
700 		cc->cpages[i] = NULL;
701 	}
702 
703 	if (cops->destroy_compress_ctx)
704 		cops->destroy_compress_ctx(cc);
705 
706 	cc->valid_nr_cpages = new_nr_cpages;
707 
708 	trace_f2fs_compress_pages_end(cc->inode, cc->cluster_idx,
709 							cc->clen, ret);
710 	return 0;
711 
712 out_vunmap_cbuf:
713 	vm_unmap_ram(cc->cbuf, cc->nr_cpages);
714 out_vunmap_rbuf:
715 	vm_unmap_ram(cc->rbuf, cc->cluster_size);
716 out_free_cpages:
717 	for (i = 0; i < cc->nr_cpages; i++) {
718 		if (cc->cpages[i])
719 			f2fs_compress_free_page(cc->cpages[i]);
720 	}
721 	page_array_free(cc->inode, cc->cpages, cc->nr_cpages);
722 	cc->cpages = NULL;
723 destroy_compress_ctx:
724 	if (cops->destroy_compress_ctx)
725 		cops->destroy_compress_ctx(cc);
726 out:
727 	trace_f2fs_compress_pages_end(cc->inode, cc->cluster_idx,
728 							cc->clen, ret);
729 	return ret;
730 }
731 
732 static int f2fs_prepare_decomp_mem(struct decompress_io_ctx *dic,
733 		bool pre_alloc);
734 static void f2fs_release_decomp_mem(struct decompress_io_ctx *dic,
735 		bool bypass_destroy_callback, bool pre_alloc);
736 
f2fs_decompress_cluster(struct decompress_io_ctx * dic,bool in_task)737 void f2fs_decompress_cluster(struct decompress_io_ctx *dic, bool in_task)
738 {
739 	struct f2fs_sb_info *sbi = F2FS_I_SB(dic->inode);
740 	struct f2fs_inode_info *fi = F2FS_I(dic->inode);
741 	const struct f2fs_compress_ops *cops =
742 			f2fs_cops[fi->i_compress_algorithm];
743 	bool bypass_callback = false;
744 	int ret;
745 
746 	trace_f2fs_decompress_pages_start(dic->inode, dic->cluster_idx,
747 				dic->cluster_size, fi->i_compress_algorithm);
748 
749 	if (dic->failed) {
750 		ret = -EIO;
751 		goto out_end_io;
752 	}
753 
754 	ret = f2fs_prepare_decomp_mem(dic, false);
755 	if (ret) {
756 		bypass_callback = true;
757 		goto out_release;
758 	}
759 
760 	dic->clen = le32_to_cpu(dic->cbuf->clen);
761 	dic->rlen = PAGE_SIZE << dic->log_cluster_size;
762 
763 	if (dic->clen > PAGE_SIZE * dic->nr_cpages - COMPRESS_HEADER_SIZE) {
764 		ret = -EFSCORRUPTED;
765 		f2fs_handle_error(sbi, ERROR_FAIL_DECOMPRESSION);
766 		goto out_release;
767 	}
768 
769 	ret = cops->decompress_pages(dic);
770 
771 	if (!ret && (fi->i_compress_flag & 1 << COMPRESS_CHKSUM)) {
772 		u32 provided = le32_to_cpu(dic->cbuf->chksum);
773 		u32 calculated = f2fs_crc32(sbi, dic->cbuf->cdata, dic->clen);
774 
775 		if (provided != calculated) {
776 			if (!is_inode_flag_set(dic->inode, FI_COMPRESS_CORRUPT)) {
777 				set_inode_flag(dic->inode, FI_COMPRESS_CORRUPT);
778 				printk_ratelimited(
779 					"%sF2FS-fs (%s): checksum invalid, nid = %lu, %x vs %x",
780 					KERN_INFO, sbi->sb->s_id, dic->inode->i_ino,
781 					provided, calculated);
782 			}
783 			set_sbi_flag(sbi, SBI_NEED_FSCK);
784 		}
785 	}
786 
787 out_release:
788 	f2fs_release_decomp_mem(dic, bypass_callback, false);
789 
790 out_end_io:
791 	trace_f2fs_decompress_pages_end(dic->inode, dic->cluster_idx,
792 							dic->clen, ret);
793 	f2fs_decompress_end_io(dic, ret, in_task);
794 }
795 
796 /*
797  * This is called when a page of a compressed cluster has been read from disk
798  * (or failed to be read from disk).  It checks whether this page was the last
799  * page being waited on in the cluster, and if so, it decompresses the cluster
800  * (or in the case of a failure, cleans up without actually decompressing).
801  */
f2fs_end_read_compressed_page(struct page * page,bool failed,block_t blkaddr,bool in_task)802 void f2fs_end_read_compressed_page(struct page *page, bool failed,
803 		block_t blkaddr, bool in_task)
804 {
805 	struct decompress_io_ctx *dic =
806 			(struct decompress_io_ctx *)page_private(page);
807 	struct f2fs_sb_info *sbi = F2FS_I_SB(dic->inode);
808 
809 	dec_page_count(sbi, F2FS_RD_DATA);
810 
811 	if (failed)
812 		WRITE_ONCE(dic->failed, true);
813 	else if (blkaddr && in_task)
814 		f2fs_cache_compressed_page(sbi, page,
815 					dic->inode->i_ino, blkaddr);
816 
817 	if (atomic_dec_and_test(&dic->remaining_pages))
818 		f2fs_decompress_cluster(dic, in_task);
819 }
820 
is_page_in_cluster(struct compress_ctx * cc,pgoff_t index)821 static bool is_page_in_cluster(struct compress_ctx *cc, pgoff_t index)
822 {
823 	if (cc->cluster_idx == NULL_CLUSTER)
824 		return true;
825 	return cc->cluster_idx == cluster_idx(cc, index);
826 }
827 
f2fs_cluster_is_empty(struct compress_ctx * cc)828 bool f2fs_cluster_is_empty(struct compress_ctx *cc)
829 {
830 	return cc->nr_rpages == 0;
831 }
832 
f2fs_cluster_is_full(struct compress_ctx * cc)833 static bool f2fs_cluster_is_full(struct compress_ctx *cc)
834 {
835 	return cc->cluster_size == cc->nr_rpages;
836 }
837 
f2fs_cluster_can_merge_page(struct compress_ctx * cc,pgoff_t index)838 bool f2fs_cluster_can_merge_page(struct compress_ctx *cc, pgoff_t index)
839 {
840 	if (f2fs_cluster_is_empty(cc))
841 		return true;
842 	return is_page_in_cluster(cc, index);
843 }
844 
f2fs_all_cluster_page_ready(struct compress_ctx * cc,struct page ** pages,int index,int nr_pages,bool uptodate)845 bool f2fs_all_cluster_page_ready(struct compress_ctx *cc, struct page **pages,
846 				int index, int nr_pages, bool uptodate)
847 {
848 	unsigned long pgidx = pages[index]->index;
849 	int i = uptodate ? 0 : 1;
850 
851 	/*
852 	 * when uptodate set to true, try to check all pages in cluster is
853 	 * uptodate or not.
854 	 */
855 	if (uptodate && (pgidx % cc->cluster_size))
856 		return false;
857 
858 	if (nr_pages - index < cc->cluster_size)
859 		return false;
860 
861 	for (; i < cc->cluster_size; i++) {
862 		if (pages[index + i]->index != pgidx + i)
863 			return false;
864 		if (uptodate && !PageUptodate(pages[index + i]))
865 			return false;
866 	}
867 
868 	return true;
869 }
870 
cluster_has_invalid_data(struct compress_ctx * cc)871 static bool cluster_has_invalid_data(struct compress_ctx *cc)
872 {
873 	loff_t i_size = i_size_read(cc->inode);
874 	unsigned nr_pages = DIV_ROUND_UP(i_size, PAGE_SIZE);
875 	int i;
876 
877 	for (i = 0; i < cc->cluster_size; i++) {
878 		struct page *page = cc->rpages[i];
879 
880 		f2fs_bug_on(F2FS_I_SB(cc->inode), !page);
881 
882 		/* beyond EOF */
883 		if (page->index >= nr_pages)
884 			return true;
885 	}
886 	return false;
887 }
888 
f2fs_sanity_check_cluster(struct dnode_of_data * dn)889 bool f2fs_sanity_check_cluster(struct dnode_of_data *dn)
890 {
891 	struct f2fs_sb_info *sbi = F2FS_I_SB(dn->inode);
892 	unsigned int cluster_size = F2FS_I(dn->inode)->i_cluster_size;
893 	bool compressed = dn->data_blkaddr == COMPRESS_ADDR;
894 	int cluster_end = 0;
895 	int i;
896 	char *reason = "";
897 
898 	if (!compressed)
899 		return false;
900 
901 	/* [..., COMPR_ADDR, ...] */
902 	if (dn->ofs_in_node % cluster_size) {
903 		reason = "[*|C|*|*]";
904 		goto out;
905 	}
906 
907 	for (i = 1; i < cluster_size; i++) {
908 		block_t blkaddr = data_blkaddr(dn->inode, dn->node_page,
909 							dn->ofs_in_node + i);
910 
911 		/* [COMPR_ADDR, ..., COMPR_ADDR] */
912 		if (blkaddr == COMPRESS_ADDR) {
913 			reason = "[C|*|C|*]";
914 			goto out;
915 		}
916 		if (!__is_valid_data_blkaddr(blkaddr)) {
917 			if (!cluster_end)
918 				cluster_end = i;
919 			continue;
920 		}
921 		/* [COMPR_ADDR, NULL_ADDR or NEW_ADDR, valid_blkaddr] */
922 		if (cluster_end) {
923 			reason = "[C|N|N|V]";
924 			goto out;
925 		}
926 	}
927 	return false;
928 out:
929 	f2fs_warn(sbi, "access invalid cluster, ino:%lu, nid:%u, ofs_in_node:%u, reason:%s",
930 			dn->inode->i_ino, dn->nid, dn->ofs_in_node, reason);
931 	set_sbi_flag(sbi, SBI_NEED_FSCK);
932 	return true;
933 }
934 
__f2fs_cluster_blocks(struct inode * inode,unsigned int cluster_idx,bool compr)935 static int __f2fs_cluster_blocks(struct inode *inode,
936 				unsigned int cluster_idx, bool compr)
937 {
938 	struct dnode_of_data dn;
939 	unsigned int cluster_size = F2FS_I(inode)->i_cluster_size;
940 	unsigned int start_idx = cluster_idx <<
941 				F2FS_I(inode)->i_log_cluster_size;
942 	int ret;
943 
944 	set_new_dnode(&dn, inode, NULL, NULL, 0);
945 	ret = f2fs_get_dnode_of_data(&dn, start_idx, LOOKUP_NODE);
946 	if (ret) {
947 		if (ret == -ENOENT)
948 			ret = 0;
949 		goto fail;
950 	}
951 
952 	if (f2fs_sanity_check_cluster(&dn)) {
953 		ret = -EFSCORRUPTED;
954 		f2fs_handle_error(F2FS_I_SB(inode), ERROR_CORRUPTED_CLUSTER);
955 		goto fail;
956 	}
957 
958 	if (dn.data_blkaddr == COMPRESS_ADDR) {
959 		int i;
960 
961 		ret = 1;
962 		for (i = 1; i < cluster_size; i++) {
963 			block_t blkaddr;
964 
965 			blkaddr = data_blkaddr(dn.inode,
966 					dn.node_page, dn.ofs_in_node + i);
967 			if (compr) {
968 				if (__is_valid_data_blkaddr(blkaddr))
969 					ret++;
970 			} else {
971 				if (blkaddr != NULL_ADDR)
972 					ret++;
973 			}
974 		}
975 
976 		f2fs_bug_on(F2FS_I_SB(inode),
977 			!compr && ret != cluster_size &&
978 			!is_inode_flag_set(inode, FI_COMPRESS_RELEASED));
979 	}
980 fail:
981 	f2fs_put_dnode(&dn);
982 	return ret;
983 }
984 
985 /* return # of compressed blocks in compressed cluster */
f2fs_compressed_blocks(struct compress_ctx * cc)986 static int f2fs_compressed_blocks(struct compress_ctx *cc)
987 {
988 	return __f2fs_cluster_blocks(cc->inode, cc->cluster_idx, true);
989 }
990 
991 /* return # of valid blocks in compressed cluster */
f2fs_is_compressed_cluster(struct inode * inode,pgoff_t index)992 int f2fs_is_compressed_cluster(struct inode *inode, pgoff_t index)
993 {
994 	return __f2fs_cluster_blocks(inode,
995 		index >> F2FS_I(inode)->i_log_cluster_size,
996 		false);
997 }
998 
cluster_may_compress(struct compress_ctx * cc)999 static bool cluster_may_compress(struct compress_ctx *cc)
1000 {
1001 	if (!f2fs_need_compress_data(cc->inode))
1002 		return false;
1003 	if (f2fs_is_atomic_file(cc->inode))
1004 		return false;
1005 	if (!f2fs_cluster_is_full(cc))
1006 		return false;
1007 	if (unlikely(f2fs_cp_error(F2FS_I_SB(cc->inode))))
1008 		return false;
1009 	return !cluster_has_invalid_data(cc);
1010 }
1011 
set_cluster_writeback(struct compress_ctx * cc)1012 static void set_cluster_writeback(struct compress_ctx *cc)
1013 {
1014 	int i;
1015 
1016 	for (i = 0; i < cc->cluster_size; i++) {
1017 		if (cc->rpages[i])
1018 			set_page_writeback(cc->rpages[i]);
1019 	}
1020 }
1021 
set_cluster_dirty(struct compress_ctx * cc)1022 static void set_cluster_dirty(struct compress_ctx *cc)
1023 {
1024 	int i;
1025 
1026 	for (i = 0; i < cc->cluster_size; i++)
1027 		if (cc->rpages[i])
1028 			set_page_dirty(cc->rpages[i]);
1029 }
1030 
prepare_compress_overwrite(struct compress_ctx * cc,struct page ** pagep,pgoff_t index,void ** fsdata)1031 static int prepare_compress_overwrite(struct compress_ctx *cc,
1032 		struct page **pagep, pgoff_t index, void **fsdata)
1033 {
1034 	struct f2fs_sb_info *sbi = F2FS_I_SB(cc->inode);
1035 	struct address_space *mapping = cc->inode->i_mapping;
1036 	struct page *page;
1037 	sector_t last_block_in_bio;
1038 	unsigned fgp_flag = FGP_LOCK | FGP_WRITE | FGP_CREAT;
1039 	pgoff_t start_idx = start_idx_of_cluster(cc);
1040 	int i, ret;
1041 
1042 retry:
1043 	ret = f2fs_is_compressed_cluster(cc->inode, start_idx);
1044 	if (ret <= 0)
1045 		return ret;
1046 
1047 	ret = f2fs_init_compress_ctx(cc);
1048 	if (ret)
1049 		return ret;
1050 
1051 	/* keep page reference to avoid page reclaim */
1052 	for (i = 0; i < cc->cluster_size; i++) {
1053 		page = f2fs_pagecache_get_page(mapping, start_idx + i,
1054 							fgp_flag, GFP_NOFS);
1055 		if (!page) {
1056 			ret = -ENOMEM;
1057 			goto unlock_pages;
1058 		}
1059 
1060 		if (PageUptodate(page))
1061 			f2fs_put_page(page, 1);
1062 		else
1063 			f2fs_compress_ctx_add_page(cc, page);
1064 	}
1065 
1066 	if (!f2fs_cluster_is_empty(cc)) {
1067 		struct bio *bio = NULL;
1068 
1069 		ret = f2fs_read_multi_pages(cc, &bio, cc->cluster_size,
1070 					&last_block_in_bio, false, true);
1071 		f2fs_put_rpages(cc);
1072 		f2fs_destroy_compress_ctx(cc, true);
1073 		if (ret)
1074 			goto out;
1075 		if (bio)
1076 			f2fs_submit_bio(sbi, bio, DATA);
1077 
1078 		ret = f2fs_init_compress_ctx(cc);
1079 		if (ret)
1080 			goto out;
1081 	}
1082 
1083 	for (i = 0; i < cc->cluster_size; i++) {
1084 		f2fs_bug_on(sbi, cc->rpages[i]);
1085 
1086 		page = find_lock_page(mapping, start_idx + i);
1087 		if (!page) {
1088 			/* page can be truncated */
1089 			goto release_and_retry;
1090 		}
1091 
1092 		f2fs_wait_on_page_writeback(page, DATA, true, true);
1093 		f2fs_compress_ctx_add_page(cc, page);
1094 
1095 		if (!PageUptodate(page)) {
1096 release_and_retry:
1097 			f2fs_put_rpages(cc);
1098 			f2fs_unlock_rpages(cc, i + 1);
1099 			f2fs_destroy_compress_ctx(cc, true);
1100 			goto retry;
1101 		}
1102 	}
1103 
1104 	if (likely(!ret)) {
1105 		*fsdata = cc->rpages;
1106 		*pagep = cc->rpages[offset_in_cluster(cc, index)];
1107 		return cc->cluster_size;
1108 	}
1109 
1110 unlock_pages:
1111 	f2fs_put_rpages(cc);
1112 	f2fs_unlock_rpages(cc, i);
1113 	f2fs_destroy_compress_ctx(cc, true);
1114 out:
1115 	return ret;
1116 }
1117 
f2fs_prepare_compress_overwrite(struct inode * inode,struct page ** pagep,pgoff_t index,void ** fsdata)1118 int f2fs_prepare_compress_overwrite(struct inode *inode,
1119 		struct page **pagep, pgoff_t index, void **fsdata)
1120 {
1121 	struct compress_ctx cc = {
1122 		.inode = inode,
1123 		.log_cluster_size = F2FS_I(inode)->i_log_cluster_size,
1124 		.cluster_size = F2FS_I(inode)->i_cluster_size,
1125 		.cluster_idx = index >> F2FS_I(inode)->i_log_cluster_size,
1126 		.rpages = NULL,
1127 		.nr_rpages = 0,
1128 	};
1129 
1130 	return prepare_compress_overwrite(&cc, pagep, index, fsdata);
1131 }
1132 
f2fs_compress_write_end(struct inode * inode,void * fsdata,pgoff_t index,unsigned copied)1133 bool f2fs_compress_write_end(struct inode *inode, void *fsdata,
1134 					pgoff_t index, unsigned copied)
1135 
1136 {
1137 	struct compress_ctx cc = {
1138 		.inode = inode,
1139 		.log_cluster_size = F2FS_I(inode)->i_log_cluster_size,
1140 		.cluster_size = F2FS_I(inode)->i_cluster_size,
1141 		.rpages = fsdata,
1142 	};
1143 	bool first_index = (index == cc.rpages[0]->index);
1144 
1145 	if (copied)
1146 		set_cluster_dirty(&cc);
1147 
1148 	f2fs_put_rpages_wbc(&cc, NULL, false, 1);
1149 	f2fs_destroy_compress_ctx(&cc, false);
1150 
1151 	return first_index;
1152 }
1153 
f2fs_truncate_partial_cluster(struct inode * inode,u64 from,bool lock)1154 int f2fs_truncate_partial_cluster(struct inode *inode, u64 from, bool lock)
1155 {
1156 	void *fsdata = NULL;
1157 	struct page *pagep;
1158 	int log_cluster_size = F2FS_I(inode)->i_log_cluster_size;
1159 	pgoff_t start_idx = from >> (PAGE_SHIFT + log_cluster_size) <<
1160 							log_cluster_size;
1161 	int err;
1162 
1163 	err = f2fs_is_compressed_cluster(inode, start_idx);
1164 	if (err < 0)
1165 		return err;
1166 
1167 	/* truncate normal cluster */
1168 	if (!err)
1169 		return f2fs_do_truncate_blocks(inode, from, lock);
1170 
1171 	/* truncate compressed cluster */
1172 	err = f2fs_prepare_compress_overwrite(inode, &pagep,
1173 						start_idx, &fsdata);
1174 
1175 	/* should not be a normal cluster */
1176 	f2fs_bug_on(F2FS_I_SB(inode), err == 0);
1177 
1178 	if (err <= 0)
1179 		return err;
1180 
1181 	if (err > 0) {
1182 		struct page **rpages = fsdata;
1183 		int cluster_size = F2FS_I(inode)->i_cluster_size;
1184 		int i;
1185 
1186 		for (i = cluster_size - 1; i >= 0; i--) {
1187 			loff_t start = rpages[i]->index << PAGE_SHIFT;
1188 
1189 			if (from <= start) {
1190 				zero_user_segment(rpages[i], 0, PAGE_SIZE);
1191 			} else {
1192 				zero_user_segment(rpages[i], from - start,
1193 								PAGE_SIZE);
1194 				break;
1195 			}
1196 		}
1197 
1198 		f2fs_compress_write_end(inode, fsdata, start_idx, true);
1199 	}
1200 	return 0;
1201 }
1202 
f2fs_write_compressed_pages(struct compress_ctx * cc,int * submitted,struct writeback_control * wbc,enum iostat_type io_type)1203 static int f2fs_write_compressed_pages(struct compress_ctx *cc,
1204 					int *submitted,
1205 					struct writeback_control *wbc,
1206 					enum iostat_type io_type)
1207 {
1208 	struct inode *inode = cc->inode;
1209 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
1210 	struct f2fs_inode_info *fi = F2FS_I(inode);
1211 	struct f2fs_io_info fio = {
1212 		.sbi = sbi,
1213 		.ino = cc->inode->i_ino,
1214 		.type = DATA,
1215 		.op = REQ_OP_WRITE,
1216 		.op_flags = wbc_to_write_flags(wbc),
1217 		.old_blkaddr = NEW_ADDR,
1218 		.page = NULL,
1219 		.encrypted_page = NULL,
1220 		.compressed_page = NULL,
1221 		.submitted = false,
1222 		.io_type = io_type,
1223 		.io_wbc = wbc,
1224 		.encrypted = fscrypt_inode_uses_fs_layer_crypto(cc->inode),
1225 	};
1226 	struct dnode_of_data dn;
1227 	struct node_info ni;
1228 	struct compress_io_ctx *cic;
1229 	pgoff_t start_idx = start_idx_of_cluster(cc);
1230 	unsigned int last_index = cc->cluster_size - 1;
1231 	loff_t psize;
1232 	int i, err;
1233 
1234 	/* we should bypass data pages to proceed the kworkder jobs */
1235 	if (unlikely(f2fs_cp_error(sbi))) {
1236 		mapping_set_error(cc->rpages[0]->mapping, -EIO);
1237 		goto out_free;
1238 	}
1239 
1240 	if (IS_NOQUOTA(inode)) {
1241 		/*
1242 		 * We need to wait for node_write to avoid block allocation during
1243 		 * checkpoint. This can only happen to quota writes which can cause
1244 		 * the below discard race condition.
1245 		 */
1246 		f2fs_down_read(&sbi->node_write);
1247 	} else if (!f2fs_trylock_op(sbi)) {
1248 		goto out_free;
1249 	}
1250 
1251 	set_new_dnode(&dn, cc->inode, NULL, NULL, 0);
1252 
1253 	err = f2fs_get_dnode_of_data(&dn, start_idx, LOOKUP_NODE);
1254 	if (err)
1255 		goto out_unlock_op;
1256 
1257 	for (i = 0; i < cc->cluster_size; i++) {
1258 		if (data_blkaddr(dn.inode, dn.node_page,
1259 					dn.ofs_in_node + i) == NULL_ADDR)
1260 			goto out_put_dnode;
1261 	}
1262 
1263 	psize = (loff_t)(cc->rpages[last_index]->index + 1) << PAGE_SHIFT;
1264 
1265 	err = f2fs_get_node_info(fio.sbi, dn.nid, &ni, false);
1266 	if (err)
1267 		goto out_put_dnode;
1268 
1269 	fio.version = ni.version;
1270 
1271 	cic = f2fs_kmem_cache_alloc(cic_entry_slab, GFP_F2FS_ZERO, false, sbi);
1272 	if (!cic)
1273 		goto out_put_dnode;
1274 
1275 	cic->magic = F2FS_COMPRESSED_PAGE_MAGIC;
1276 	cic->inode = inode;
1277 	atomic_set(&cic->pending_pages, cc->valid_nr_cpages);
1278 	cic->rpages = page_array_alloc(cc->inode, cc->cluster_size);
1279 	if (!cic->rpages)
1280 		goto out_put_cic;
1281 
1282 	cic->nr_rpages = cc->cluster_size;
1283 
1284 	for (i = 0; i < cc->valid_nr_cpages; i++) {
1285 		f2fs_set_compressed_page(cc->cpages[i], inode,
1286 					cc->rpages[i + 1]->index, cic);
1287 		fio.compressed_page = cc->cpages[i];
1288 
1289 		fio.old_blkaddr = data_blkaddr(dn.inode, dn.node_page,
1290 						dn.ofs_in_node + i + 1);
1291 
1292 		/* wait for GCed page writeback via META_MAPPING */
1293 		f2fs_wait_on_block_writeback(inode, fio.old_blkaddr);
1294 
1295 		if (fio.encrypted) {
1296 			fio.page = cc->rpages[i + 1];
1297 			err = f2fs_encrypt_one_page(&fio);
1298 			if (err)
1299 				goto out_destroy_crypt;
1300 			cc->cpages[i] = fio.encrypted_page;
1301 		}
1302 	}
1303 
1304 	set_cluster_writeback(cc);
1305 
1306 	for (i = 0; i < cc->cluster_size; i++)
1307 		cic->rpages[i] = cc->rpages[i];
1308 
1309 	for (i = 0; i < cc->cluster_size; i++, dn.ofs_in_node++) {
1310 		block_t blkaddr;
1311 
1312 		blkaddr = f2fs_data_blkaddr(&dn);
1313 		fio.page = cc->rpages[i];
1314 		fio.old_blkaddr = blkaddr;
1315 
1316 		/* cluster header */
1317 		if (i == 0) {
1318 			if (blkaddr == COMPRESS_ADDR)
1319 				fio.compr_blocks++;
1320 			if (__is_valid_data_blkaddr(blkaddr))
1321 				f2fs_invalidate_blocks(sbi, blkaddr);
1322 			f2fs_update_data_blkaddr(&dn, COMPRESS_ADDR);
1323 			goto unlock_continue;
1324 		}
1325 
1326 		if (fio.compr_blocks && __is_valid_data_blkaddr(blkaddr))
1327 			fio.compr_blocks++;
1328 
1329 		if (i > cc->valid_nr_cpages) {
1330 			if (__is_valid_data_blkaddr(blkaddr)) {
1331 				f2fs_invalidate_blocks(sbi, blkaddr);
1332 				f2fs_update_data_blkaddr(&dn, NEW_ADDR);
1333 			}
1334 			goto unlock_continue;
1335 		}
1336 
1337 		f2fs_bug_on(fio.sbi, blkaddr == NULL_ADDR);
1338 
1339 		if (fio.encrypted)
1340 			fio.encrypted_page = cc->cpages[i - 1];
1341 		else
1342 			fio.compressed_page = cc->cpages[i - 1];
1343 
1344 		cc->cpages[i - 1] = NULL;
1345 		f2fs_outplace_write_data(&dn, &fio);
1346 		(*submitted)++;
1347 unlock_continue:
1348 		inode_dec_dirty_pages(cc->inode);
1349 		unlock_page(fio.page);
1350 	}
1351 
1352 	if (fio.compr_blocks)
1353 		f2fs_i_compr_blocks_update(inode, fio.compr_blocks - 1, false);
1354 	f2fs_i_compr_blocks_update(inode, cc->valid_nr_cpages, true);
1355 	add_compr_block_stat(inode, cc->valid_nr_cpages);
1356 
1357 	set_inode_flag(cc->inode, FI_APPEND_WRITE);
1358 	if (cc->cluster_idx == 0)
1359 		set_inode_flag(inode, FI_FIRST_BLOCK_WRITTEN);
1360 
1361 	f2fs_put_dnode(&dn);
1362 	if (IS_NOQUOTA(inode))
1363 		f2fs_up_read(&sbi->node_write);
1364 	else
1365 		f2fs_unlock_op(sbi);
1366 
1367 	spin_lock(&fi->i_size_lock);
1368 	if (fi->last_disk_size < psize)
1369 		fi->last_disk_size = psize;
1370 	spin_unlock(&fi->i_size_lock);
1371 
1372 	f2fs_put_rpages(cc);
1373 	page_array_free(cc->inode, cc->cpages, cc->nr_cpages);
1374 	cc->cpages = NULL;
1375 	f2fs_destroy_compress_ctx(cc, false);
1376 	return 0;
1377 
1378 out_destroy_crypt:
1379 	page_array_free(cc->inode, cic->rpages, cc->cluster_size);
1380 
1381 	for (--i; i >= 0; i--)
1382 		fscrypt_finalize_bounce_page(&cc->cpages[i]);
1383 out_put_cic:
1384 	kmem_cache_free(cic_entry_slab, cic);
1385 out_put_dnode:
1386 	f2fs_put_dnode(&dn);
1387 out_unlock_op:
1388 	if (IS_NOQUOTA(inode))
1389 		f2fs_up_read(&sbi->node_write);
1390 	else
1391 		f2fs_unlock_op(sbi);
1392 out_free:
1393 	for (i = 0; i < cc->valid_nr_cpages; i++) {
1394 		f2fs_compress_free_page(cc->cpages[i]);
1395 		cc->cpages[i] = NULL;
1396 	}
1397 	page_array_free(cc->inode, cc->cpages, cc->nr_cpages);
1398 	cc->cpages = NULL;
1399 	return -EAGAIN;
1400 }
1401 
f2fs_compress_write_end_io(struct bio * bio,struct page * page)1402 void f2fs_compress_write_end_io(struct bio *bio, struct page *page)
1403 {
1404 	struct f2fs_sb_info *sbi = bio->bi_private;
1405 	struct compress_io_ctx *cic =
1406 			(struct compress_io_ctx *)page_private(page);
1407 	int i;
1408 
1409 	if (unlikely(bio->bi_status))
1410 		mapping_set_error(cic->inode->i_mapping, -EIO);
1411 
1412 	f2fs_compress_free_page(page);
1413 
1414 	dec_page_count(sbi, F2FS_WB_DATA);
1415 
1416 	if (atomic_dec_return(&cic->pending_pages))
1417 		return;
1418 
1419 	for (i = 0; i < cic->nr_rpages; i++) {
1420 		WARN_ON(!cic->rpages[i]);
1421 		clear_page_private_gcing(cic->rpages[i]);
1422 		end_page_writeback(cic->rpages[i]);
1423 	}
1424 
1425 	page_array_free(cic->inode, cic->rpages, cic->nr_rpages);
1426 	kmem_cache_free(cic_entry_slab, cic);
1427 }
1428 
f2fs_write_raw_pages(struct compress_ctx * cc,int * submitted,struct writeback_control * wbc,enum iostat_type io_type)1429 static int f2fs_write_raw_pages(struct compress_ctx *cc,
1430 					int *submitted,
1431 					struct writeback_control *wbc,
1432 					enum iostat_type io_type)
1433 {
1434 	struct address_space *mapping = cc->inode->i_mapping;
1435 	int _submitted, compr_blocks, ret, i;
1436 
1437 	compr_blocks = f2fs_compressed_blocks(cc);
1438 
1439 	for (i = 0; i < cc->cluster_size; i++) {
1440 		if (!cc->rpages[i])
1441 			continue;
1442 
1443 		redirty_page_for_writepage(wbc, cc->rpages[i]);
1444 		unlock_page(cc->rpages[i]);
1445 	}
1446 
1447 	if (compr_blocks < 0)
1448 		return compr_blocks;
1449 
1450 	for (i = 0; i < cc->cluster_size; i++) {
1451 		if (!cc->rpages[i])
1452 			continue;
1453 retry_write:
1454 		lock_page(cc->rpages[i]);
1455 
1456 		if (cc->rpages[i]->mapping != mapping) {
1457 continue_unlock:
1458 			unlock_page(cc->rpages[i]);
1459 			continue;
1460 		}
1461 
1462 		if (!PageDirty(cc->rpages[i]))
1463 			goto continue_unlock;
1464 
1465 		if (!clear_page_dirty_for_io(cc->rpages[i]))
1466 			goto continue_unlock;
1467 
1468 		ret = f2fs_write_single_data_page(cc->rpages[i], &_submitted,
1469 						NULL, NULL, wbc, io_type,
1470 						compr_blocks, false);
1471 		if (ret) {
1472 			if (ret == AOP_WRITEPAGE_ACTIVATE) {
1473 				unlock_page(cc->rpages[i]);
1474 				ret = 0;
1475 			} else if (ret == -EAGAIN) {
1476 				/*
1477 				 * for quota file, just redirty left pages to
1478 				 * avoid deadlock caused by cluster update race
1479 				 * from foreground operation.
1480 				 */
1481 				if (IS_NOQUOTA(cc->inode))
1482 					return 0;
1483 				ret = 0;
1484 				f2fs_io_schedule_timeout(DEFAULT_IO_TIMEOUT);
1485 				goto retry_write;
1486 			}
1487 			return ret;
1488 		}
1489 
1490 		*submitted += _submitted;
1491 	}
1492 
1493 	f2fs_balance_fs(F2FS_M_SB(mapping), true);
1494 
1495 	return 0;
1496 }
1497 
f2fs_write_multi_pages(struct compress_ctx * cc,int * submitted,struct writeback_control * wbc,enum iostat_type io_type)1498 int f2fs_write_multi_pages(struct compress_ctx *cc,
1499 					int *submitted,
1500 					struct writeback_control *wbc,
1501 					enum iostat_type io_type)
1502 {
1503 	int err;
1504 
1505 	*submitted = 0;
1506 	if (cluster_may_compress(cc)) {
1507 		err = f2fs_compress_pages(cc);
1508 		if (err == -EAGAIN) {
1509 			add_compr_block_stat(cc->inode, cc->cluster_size);
1510 			goto write;
1511 		} else if (err) {
1512 			f2fs_put_rpages_wbc(cc, wbc, true, 1);
1513 			goto destroy_out;
1514 		}
1515 
1516 		err = f2fs_write_compressed_pages(cc, submitted,
1517 							wbc, io_type);
1518 		if (!err)
1519 			return 0;
1520 		f2fs_bug_on(F2FS_I_SB(cc->inode), err != -EAGAIN);
1521 	}
1522 write:
1523 	f2fs_bug_on(F2FS_I_SB(cc->inode), *submitted);
1524 
1525 	err = f2fs_write_raw_pages(cc, submitted, wbc, io_type);
1526 	f2fs_put_rpages_wbc(cc, wbc, false, 0);
1527 destroy_out:
1528 	f2fs_destroy_compress_ctx(cc, false);
1529 	return err;
1530 }
1531 
allow_memalloc_for_decomp(struct f2fs_sb_info * sbi,bool pre_alloc)1532 static inline bool allow_memalloc_for_decomp(struct f2fs_sb_info *sbi,
1533 		bool pre_alloc)
1534 {
1535 	return pre_alloc ^ f2fs_low_mem_mode(sbi);
1536 }
1537 
f2fs_prepare_decomp_mem(struct decompress_io_ctx * dic,bool pre_alloc)1538 static int f2fs_prepare_decomp_mem(struct decompress_io_ctx *dic,
1539 		bool pre_alloc)
1540 {
1541 	const struct f2fs_compress_ops *cops =
1542 		f2fs_cops[F2FS_I(dic->inode)->i_compress_algorithm];
1543 	int i;
1544 
1545 	if (!allow_memalloc_for_decomp(F2FS_I_SB(dic->inode), pre_alloc))
1546 		return 0;
1547 
1548 	dic->tpages = page_array_alloc(dic->inode, dic->cluster_size);
1549 	if (!dic->tpages)
1550 		return -ENOMEM;
1551 
1552 	for (i = 0; i < dic->cluster_size; i++) {
1553 		if (dic->rpages[i]) {
1554 			dic->tpages[i] = dic->rpages[i];
1555 			continue;
1556 		}
1557 
1558 		dic->tpages[i] = f2fs_compress_alloc_page();
1559 		if (!dic->tpages[i])
1560 			return -ENOMEM;
1561 	}
1562 
1563 	dic->rbuf = f2fs_vmap(dic->tpages, dic->cluster_size);
1564 	if (!dic->rbuf)
1565 		return -ENOMEM;
1566 
1567 	dic->cbuf = f2fs_vmap(dic->cpages, dic->nr_cpages);
1568 	if (!dic->cbuf)
1569 		return -ENOMEM;
1570 
1571 	if (cops->init_decompress_ctx)
1572 		return cops->init_decompress_ctx(dic);
1573 
1574 	return 0;
1575 }
1576 
f2fs_release_decomp_mem(struct decompress_io_ctx * dic,bool bypass_destroy_callback,bool pre_alloc)1577 static void f2fs_release_decomp_mem(struct decompress_io_ctx *dic,
1578 		bool bypass_destroy_callback, bool pre_alloc)
1579 {
1580 	const struct f2fs_compress_ops *cops =
1581 		f2fs_cops[F2FS_I(dic->inode)->i_compress_algorithm];
1582 
1583 	if (!allow_memalloc_for_decomp(F2FS_I_SB(dic->inode), pre_alloc))
1584 		return;
1585 
1586 	if (!bypass_destroy_callback && cops->destroy_decompress_ctx)
1587 		cops->destroy_decompress_ctx(dic);
1588 
1589 	if (dic->cbuf)
1590 		vm_unmap_ram(dic->cbuf, dic->nr_cpages);
1591 
1592 	if (dic->rbuf)
1593 		vm_unmap_ram(dic->rbuf, dic->cluster_size);
1594 }
1595 
1596 static void f2fs_free_dic(struct decompress_io_ctx *dic,
1597 		bool bypass_destroy_callback);
1598 
f2fs_alloc_dic(struct compress_ctx * cc)1599 struct decompress_io_ctx *f2fs_alloc_dic(struct compress_ctx *cc)
1600 {
1601 	struct decompress_io_ctx *dic;
1602 	pgoff_t start_idx = start_idx_of_cluster(cc);
1603 	struct f2fs_sb_info *sbi = F2FS_I_SB(cc->inode);
1604 	int i, ret;
1605 
1606 	dic = f2fs_kmem_cache_alloc(dic_entry_slab, GFP_F2FS_ZERO, false, sbi);
1607 	if (!dic)
1608 		return ERR_PTR(-ENOMEM);
1609 
1610 	dic->rpages = page_array_alloc(cc->inode, cc->cluster_size);
1611 	if (!dic->rpages) {
1612 		kmem_cache_free(dic_entry_slab, dic);
1613 		return ERR_PTR(-ENOMEM);
1614 	}
1615 
1616 	dic->magic = F2FS_COMPRESSED_PAGE_MAGIC;
1617 	dic->inode = cc->inode;
1618 	atomic_set(&dic->remaining_pages, cc->nr_cpages);
1619 	dic->cluster_idx = cc->cluster_idx;
1620 	dic->cluster_size = cc->cluster_size;
1621 	dic->log_cluster_size = cc->log_cluster_size;
1622 	dic->nr_cpages = cc->nr_cpages;
1623 	refcount_set(&dic->refcnt, 1);
1624 	dic->failed = false;
1625 	dic->need_verity = f2fs_need_verity(cc->inode, start_idx);
1626 
1627 	for (i = 0; i < dic->cluster_size; i++)
1628 		dic->rpages[i] = cc->rpages[i];
1629 	dic->nr_rpages = cc->cluster_size;
1630 
1631 	dic->cpages = page_array_alloc(dic->inode, dic->nr_cpages);
1632 	if (!dic->cpages) {
1633 		ret = -ENOMEM;
1634 		goto out_free;
1635 	}
1636 
1637 	for (i = 0; i < dic->nr_cpages; i++) {
1638 		struct page *page;
1639 
1640 		page = f2fs_compress_alloc_page();
1641 		if (!page) {
1642 			ret = -ENOMEM;
1643 			goto out_free;
1644 		}
1645 
1646 		f2fs_set_compressed_page(page, cc->inode,
1647 					start_idx + i + 1, dic);
1648 		dic->cpages[i] = page;
1649 	}
1650 
1651 	ret = f2fs_prepare_decomp_mem(dic, true);
1652 	if (ret)
1653 		goto out_free;
1654 
1655 	return dic;
1656 
1657 out_free:
1658 	f2fs_free_dic(dic, true);
1659 	return ERR_PTR(ret);
1660 }
1661 
f2fs_free_dic(struct decompress_io_ctx * dic,bool bypass_destroy_callback)1662 static void f2fs_free_dic(struct decompress_io_ctx *dic,
1663 		bool bypass_destroy_callback)
1664 {
1665 	int i;
1666 
1667 	f2fs_release_decomp_mem(dic, bypass_destroy_callback, true);
1668 
1669 	if (dic->tpages) {
1670 		for (i = 0; i < dic->cluster_size; i++) {
1671 			if (dic->rpages[i])
1672 				continue;
1673 			if (!dic->tpages[i])
1674 				continue;
1675 			f2fs_compress_free_page(dic->tpages[i]);
1676 		}
1677 		page_array_free(dic->inode, dic->tpages, dic->cluster_size);
1678 	}
1679 
1680 	if (dic->cpages) {
1681 		for (i = 0; i < dic->nr_cpages; i++) {
1682 			if (!dic->cpages[i])
1683 				continue;
1684 			f2fs_compress_free_page(dic->cpages[i]);
1685 		}
1686 		page_array_free(dic->inode, dic->cpages, dic->nr_cpages);
1687 	}
1688 
1689 	page_array_free(dic->inode, dic->rpages, dic->nr_rpages);
1690 	kmem_cache_free(dic_entry_slab, dic);
1691 }
1692 
f2fs_late_free_dic(struct work_struct * work)1693 static void f2fs_late_free_dic(struct work_struct *work)
1694 {
1695 	struct decompress_io_ctx *dic =
1696 		container_of(work, struct decompress_io_ctx, free_work);
1697 
1698 	f2fs_free_dic(dic, false);
1699 }
1700 
f2fs_put_dic(struct decompress_io_ctx * dic,bool in_task)1701 static void f2fs_put_dic(struct decompress_io_ctx *dic, bool in_task)
1702 {
1703 	if (refcount_dec_and_test(&dic->refcnt)) {
1704 		if (in_task) {
1705 			f2fs_free_dic(dic, false);
1706 		} else {
1707 			INIT_WORK(&dic->free_work, f2fs_late_free_dic);
1708 			queue_work(F2FS_I_SB(dic->inode)->post_read_wq,
1709 					&dic->free_work);
1710 		}
1711 	}
1712 }
1713 
1714 /*
1715  * Update and unlock the cluster's pagecache pages, and release the reference to
1716  * the decompress_io_ctx that was being held for I/O completion.
1717  */
__f2fs_decompress_end_io(struct decompress_io_ctx * dic,bool failed,bool in_task)1718 static void __f2fs_decompress_end_io(struct decompress_io_ctx *dic, bool failed,
1719 				bool in_task)
1720 {
1721 	int i;
1722 
1723 	for (i = 0; i < dic->cluster_size; i++) {
1724 		struct page *rpage = dic->rpages[i];
1725 
1726 		if (!rpage)
1727 			continue;
1728 
1729 		/* PG_error was set if verity failed. */
1730 		if (failed || PageError(rpage)) {
1731 			ClearPageUptodate(rpage);
1732 			/* will re-read again later */
1733 			ClearPageError(rpage);
1734 		} else {
1735 			SetPageUptodate(rpage);
1736 		}
1737 		unlock_page(rpage);
1738 	}
1739 
1740 	f2fs_put_dic(dic, in_task);
1741 }
1742 
f2fs_verify_cluster(struct work_struct * work)1743 static void f2fs_verify_cluster(struct work_struct *work)
1744 {
1745 	struct decompress_io_ctx *dic =
1746 		container_of(work, struct decompress_io_ctx, verity_work);
1747 	int i;
1748 
1749 	/* Verify the cluster's decompressed pages with fs-verity. */
1750 	for (i = 0; i < dic->cluster_size; i++) {
1751 		struct page *rpage = dic->rpages[i];
1752 
1753 		if (rpage && !fsverity_verify_page(rpage))
1754 			SetPageError(rpage);
1755 	}
1756 
1757 	__f2fs_decompress_end_io(dic, false, true);
1758 }
1759 
1760 /*
1761  * This is called when a compressed cluster has been decompressed
1762  * (or failed to be read and/or decompressed).
1763  */
f2fs_decompress_end_io(struct decompress_io_ctx * dic,bool failed,bool in_task)1764 void f2fs_decompress_end_io(struct decompress_io_ctx *dic, bool failed,
1765 				bool in_task)
1766 {
1767 	if (!failed && dic->need_verity) {
1768 		/*
1769 		 * Note that to avoid deadlocks, the verity work can't be done
1770 		 * on the decompression workqueue.  This is because verifying
1771 		 * the data pages can involve reading metadata pages from the
1772 		 * file, and these metadata pages may be compressed.
1773 		 */
1774 		INIT_WORK(&dic->verity_work, f2fs_verify_cluster);
1775 		fsverity_enqueue_verify_work(&dic->verity_work);
1776 	} else {
1777 		__f2fs_decompress_end_io(dic, failed, in_task);
1778 	}
1779 }
1780 
1781 /*
1782  * Put a reference to a compressed page's decompress_io_ctx.
1783  *
1784  * This is called when the page is no longer needed and can be freed.
1785  */
f2fs_put_page_dic(struct page * page,bool in_task)1786 void f2fs_put_page_dic(struct page *page, bool in_task)
1787 {
1788 	struct decompress_io_ctx *dic =
1789 			(struct decompress_io_ctx *)page_private(page);
1790 
1791 	f2fs_put_dic(dic, in_task);
1792 }
1793 
1794 /*
1795  * check whether cluster blocks are contiguous, and add extent cache entry
1796  * only if cluster blocks are logically and physically contiguous.
1797  */
f2fs_cluster_blocks_are_contiguous(struct dnode_of_data * dn)1798 unsigned int f2fs_cluster_blocks_are_contiguous(struct dnode_of_data *dn)
1799 {
1800 	bool compressed = f2fs_data_blkaddr(dn) == COMPRESS_ADDR;
1801 	int i = compressed ? 1 : 0;
1802 	block_t first_blkaddr = data_blkaddr(dn->inode, dn->node_page,
1803 						dn->ofs_in_node + i);
1804 
1805 	for (i += 1; i < F2FS_I(dn->inode)->i_cluster_size; i++) {
1806 		block_t blkaddr = data_blkaddr(dn->inode, dn->node_page,
1807 						dn->ofs_in_node + i);
1808 
1809 		if (!__is_valid_data_blkaddr(blkaddr))
1810 			break;
1811 		if (first_blkaddr + i - (compressed ? 1 : 0) != blkaddr)
1812 			return 0;
1813 	}
1814 
1815 	return compressed ? i - 1 : i;
1816 }
1817 
1818 const struct address_space_operations f2fs_compress_aops = {
1819 	.release_folio = f2fs_release_folio,
1820 	.invalidate_folio = f2fs_invalidate_folio,
1821 };
1822 
COMPRESS_MAPPING(struct f2fs_sb_info * sbi)1823 struct address_space *COMPRESS_MAPPING(struct f2fs_sb_info *sbi)
1824 {
1825 	return sbi->compress_inode->i_mapping;
1826 }
1827 
f2fs_invalidate_compress_page(struct f2fs_sb_info * sbi,block_t blkaddr)1828 void f2fs_invalidate_compress_page(struct f2fs_sb_info *sbi, block_t blkaddr)
1829 {
1830 	if (!sbi->compress_inode)
1831 		return;
1832 	invalidate_mapping_pages(COMPRESS_MAPPING(sbi), blkaddr, blkaddr);
1833 }
1834 
f2fs_cache_compressed_page(struct f2fs_sb_info * sbi,struct page * page,nid_t ino,block_t blkaddr)1835 void f2fs_cache_compressed_page(struct f2fs_sb_info *sbi, struct page *page,
1836 						nid_t ino, block_t blkaddr)
1837 {
1838 	struct page *cpage;
1839 	int ret;
1840 
1841 	if (!test_opt(sbi, COMPRESS_CACHE))
1842 		return;
1843 
1844 	if (!f2fs_is_valid_blkaddr(sbi, blkaddr, DATA_GENERIC_ENHANCE_READ))
1845 		return;
1846 
1847 	if (!f2fs_available_free_memory(sbi, COMPRESS_PAGE))
1848 		return;
1849 
1850 	cpage = find_get_page(COMPRESS_MAPPING(sbi), blkaddr);
1851 	if (cpage) {
1852 		f2fs_put_page(cpage, 0);
1853 		return;
1854 	}
1855 
1856 	cpage = alloc_page(__GFP_NOWARN | __GFP_IO);
1857 	if (!cpage)
1858 		return;
1859 
1860 	ret = add_to_page_cache_lru(cpage, COMPRESS_MAPPING(sbi),
1861 						blkaddr, GFP_NOFS);
1862 	if (ret) {
1863 		f2fs_put_page(cpage, 0);
1864 		return;
1865 	}
1866 
1867 	set_page_private_data(cpage, ino);
1868 
1869 	if (!f2fs_is_valid_blkaddr(sbi, blkaddr, DATA_GENERIC_ENHANCE_READ))
1870 		goto out;
1871 
1872 	memcpy(page_address(cpage), page_address(page), PAGE_SIZE);
1873 	SetPageUptodate(cpage);
1874 out:
1875 	f2fs_put_page(cpage, 1);
1876 }
1877 
f2fs_load_compressed_page(struct f2fs_sb_info * sbi,struct page * page,block_t blkaddr)1878 bool f2fs_load_compressed_page(struct f2fs_sb_info *sbi, struct page *page,
1879 								block_t blkaddr)
1880 {
1881 	struct page *cpage;
1882 	bool hitted = false;
1883 
1884 	if (!test_opt(sbi, COMPRESS_CACHE))
1885 		return false;
1886 
1887 	cpage = f2fs_pagecache_get_page(COMPRESS_MAPPING(sbi),
1888 				blkaddr, FGP_LOCK | FGP_NOWAIT, GFP_NOFS);
1889 	if (cpage) {
1890 		if (PageUptodate(cpage)) {
1891 			atomic_inc(&sbi->compress_page_hit);
1892 			memcpy(page_address(page),
1893 				page_address(cpage), PAGE_SIZE);
1894 			hitted = true;
1895 		}
1896 		f2fs_put_page(cpage, 1);
1897 	}
1898 
1899 	return hitted;
1900 }
1901 
f2fs_invalidate_compress_pages(struct f2fs_sb_info * sbi,nid_t ino)1902 void f2fs_invalidate_compress_pages(struct f2fs_sb_info *sbi, nid_t ino)
1903 {
1904 	struct address_space *mapping = COMPRESS_MAPPING(sbi);
1905 	struct folio_batch fbatch;
1906 	pgoff_t index = 0;
1907 	pgoff_t end = MAX_BLKADDR(sbi);
1908 
1909 	if (!mapping->nrpages)
1910 		return;
1911 
1912 	folio_batch_init(&fbatch);
1913 
1914 	do {
1915 		unsigned int nr, i;
1916 
1917 		nr = filemap_get_folios(mapping, &index, end - 1, &fbatch);
1918 		if (!nr)
1919 			break;
1920 
1921 		for (i = 0; i < nr; i++) {
1922 			struct folio *folio = fbatch.folios[i];
1923 
1924 			folio_lock(folio);
1925 			if (folio->mapping != mapping) {
1926 				folio_unlock(folio);
1927 				continue;
1928 			}
1929 
1930 			if (ino != get_page_private_data(&folio->page)) {
1931 				folio_unlock(folio);
1932 				continue;
1933 			}
1934 
1935 			generic_error_remove_page(mapping, &folio->page);
1936 			folio_unlock(folio);
1937 		}
1938 		folio_batch_release(&fbatch);
1939 		cond_resched();
1940 	} while (index < end);
1941 }
1942 
f2fs_init_compress_inode(struct f2fs_sb_info * sbi)1943 int f2fs_init_compress_inode(struct f2fs_sb_info *sbi)
1944 {
1945 	struct inode *inode;
1946 
1947 	if (!test_opt(sbi, COMPRESS_CACHE))
1948 		return 0;
1949 
1950 	inode = f2fs_iget(sbi->sb, F2FS_COMPRESS_INO(sbi));
1951 	if (IS_ERR(inode))
1952 		return PTR_ERR(inode);
1953 	sbi->compress_inode = inode;
1954 
1955 	sbi->compress_percent = COMPRESS_PERCENT;
1956 	sbi->compress_watermark = COMPRESS_WATERMARK;
1957 
1958 	atomic_set(&sbi->compress_page_hit, 0);
1959 
1960 	return 0;
1961 }
1962 
f2fs_destroy_compress_inode(struct f2fs_sb_info * sbi)1963 void f2fs_destroy_compress_inode(struct f2fs_sb_info *sbi)
1964 {
1965 	if (!sbi->compress_inode)
1966 		return;
1967 	iput(sbi->compress_inode);
1968 	sbi->compress_inode = NULL;
1969 }
1970 
f2fs_init_page_array_cache(struct f2fs_sb_info * sbi)1971 int f2fs_init_page_array_cache(struct f2fs_sb_info *sbi)
1972 {
1973 	dev_t dev = sbi->sb->s_bdev->bd_dev;
1974 	char slab_name[32];
1975 
1976 	if (!f2fs_sb_has_compression(sbi))
1977 		return 0;
1978 
1979 	sprintf(slab_name, "f2fs_page_array_entry-%u:%u", MAJOR(dev), MINOR(dev));
1980 
1981 	sbi->page_array_slab_size = sizeof(struct page *) <<
1982 					F2FS_OPTION(sbi).compress_log_size;
1983 
1984 	sbi->page_array_slab = f2fs_kmem_cache_create(slab_name,
1985 					sbi->page_array_slab_size);
1986 	if (!sbi->page_array_slab)
1987 		return -ENOMEM;
1988 	return 0;
1989 }
1990 
f2fs_destroy_page_array_cache(struct f2fs_sb_info * sbi)1991 void f2fs_destroy_page_array_cache(struct f2fs_sb_info *sbi)
1992 {
1993 	kmem_cache_destroy(sbi->page_array_slab);
1994 }
1995 
f2fs_init_cic_cache(void)1996 static int __init f2fs_init_cic_cache(void)
1997 {
1998 	cic_entry_slab = f2fs_kmem_cache_create("f2fs_cic_entry",
1999 					sizeof(struct compress_io_ctx));
2000 	if (!cic_entry_slab)
2001 		return -ENOMEM;
2002 	return 0;
2003 }
2004 
f2fs_destroy_cic_cache(void)2005 static void f2fs_destroy_cic_cache(void)
2006 {
2007 	kmem_cache_destroy(cic_entry_slab);
2008 }
2009 
f2fs_init_dic_cache(void)2010 static int __init f2fs_init_dic_cache(void)
2011 {
2012 	dic_entry_slab = f2fs_kmem_cache_create("f2fs_dic_entry",
2013 					sizeof(struct decompress_io_ctx));
2014 	if (!dic_entry_slab)
2015 		return -ENOMEM;
2016 	return 0;
2017 }
2018 
f2fs_destroy_dic_cache(void)2019 static void f2fs_destroy_dic_cache(void)
2020 {
2021 	kmem_cache_destroy(dic_entry_slab);
2022 }
2023 
f2fs_init_compress_cache(void)2024 int __init f2fs_init_compress_cache(void)
2025 {
2026 	int err;
2027 
2028 	err = f2fs_init_cic_cache();
2029 	if (err)
2030 		goto out;
2031 	err = f2fs_init_dic_cache();
2032 	if (err)
2033 		goto free_cic;
2034 	return 0;
2035 free_cic:
2036 	f2fs_destroy_cic_cache();
2037 out:
2038 	return -ENOMEM;
2039 }
2040 
f2fs_destroy_compress_cache(void)2041 void f2fs_destroy_compress_cache(void)
2042 {
2043 	f2fs_destroy_dic_cache();
2044 	f2fs_destroy_cic_cache();
2045 }
2046