mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-23 17:30:02 +00:00
267f2492c8
Let's introduce multi-reference pclusters at runtime. In details, if one pcluster is requested by multiple extents at almost the same time (even belong to different files), the longest extent will be decompressed as representative and the other extents are actually copied from the longest one in one round. After this patch, fully-referenced extents can be correctly handled and the full decoding check needs to be bypassed for partial-referenced extents. Acked-by: Chao Yu <chao@kernel.org> Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com> Link: https://lore.kernel.org/r/20220715154203.48093-17-hsiangkao@linux.alibaba.com
98 lines
2.9 KiB
C
98 lines
2.9 KiB
C
/* SPDX-License-Identifier: GPL-2.0-only */
|
|
/*
|
|
* Copyright (C) 2019 HUAWEI, Inc.
|
|
* https://www.huawei.com/
|
|
*/
|
|
#ifndef __EROFS_FS_COMPRESS_H
|
|
#define __EROFS_FS_COMPRESS_H
|
|
|
|
#include "internal.h"
|
|
|
|
struct z_erofs_decompress_req {
|
|
struct super_block *sb;
|
|
struct page **in, **out;
|
|
|
|
unsigned short pageofs_in, pageofs_out;
|
|
unsigned int inputsize, outputsize;
|
|
|
|
/* indicate the algorithm will be used for decompression */
|
|
unsigned int alg;
|
|
bool inplace_io, partial_decoding, fillgaps;
|
|
};
|
|
|
|
struct z_erofs_decompressor {
|
|
int (*decompress)(struct z_erofs_decompress_req *rq,
|
|
struct page **pagepool);
|
|
char *name;
|
|
};
|
|
|
|
/* some special page->private (unsigned long, see below) */
|
|
#define Z_EROFS_SHORTLIVED_PAGE (-1UL << 2)
|
|
#define Z_EROFS_PREALLOCATED_PAGE (-2UL << 2)
|
|
|
|
/*
|
|
* For all pages in a pcluster, page->private should be one of
|
|
* Type Last 2bits page->private
|
|
* short-lived page 00 Z_EROFS_SHORTLIVED_PAGE
|
|
* preallocated page (tryalloc) 00 Z_EROFS_PREALLOCATED_PAGE
|
|
* cached/managed page 00 pointer to z_erofs_pcluster
|
|
* online page (file-backed, 01/10/11 sub-index << 2 | count
|
|
* some pages can be used for inplace I/O)
|
|
*
|
|
* page->mapping should be one of
|
|
* Type page->mapping
|
|
* short-lived page NULL
|
|
* preallocated page NULL
|
|
* cached/managed page non-NULL or NULL (invalidated/truncated page)
|
|
* online page non-NULL
|
|
*
|
|
* For all managed pages, PG_private should be set with 1 extra refcount,
|
|
* which is used for page reclaim / migration.
|
|
*/
|
|
|
|
/*
|
|
* short-lived pages are pages directly from buddy system with specific
|
|
* page->private (no need to set PagePrivate since these are non-LRU /
|
|
* non-movable pages and bypass reclaim / migration code).
|
|
*/
|
|
static inline bool z_erofs_is_shortlived_page(struct page *page)
|
|
{
|
|
if (page->private != Z_EROFS_SHORTLIVED_PAGE)
|
|
return false;
|
|
|
|
DBG_BUGON(page->mapping);
|
|
return true;
|
|
}
|
|
|
|
static inline bool z_erofs_put_shortlivedpage(struct page **pagepool,
|
|
struct page *page)
|
|
{
|
|
if (!z_erofs_is_shortlived_page(page))
|
|
return false;
|
|
|
|
/* short-lived pages should not be used by others at the same time */
|
|
if (page_ref_count(page) > 1) {
|
|
put_page(page);
|
|
} else {
|
|
/* follow the pcluster rule above. */
|
|
erofs_pagepool_add(pagepool, page);
|
|
}
|
|
return true;
|
|
}
|
|
|
|
#define MNGD_MAPPING(sbi) ((sbi)->managed_cache->i_mapping)
|
|
static inline bool erofs_page_is_managed(const struct erofs_sb_info *sbi,
|
|
struct page *page)
|
|
{
|
|
return page->mapping == MNGD_MAPPING(sbi);
|
|
}
|
|
|
|
int z_erofs_fixup_insize(struct z_erofs_decompress_req *rq, const char *padbuf,
|
|
unsigned int padbufsize);
|
|
int z_erofs_decompress(struct z_erofs_decompress_req *rq,
|
|
struct page **pagepool);
|
|
|
|
/* prototypes for specific algorithms */
|
|
int z_erofs_lzma_decompress(struct z_erofs_decompress_req *rq,
|
|
struct page **pagepool);
|
|
#endif
|