/* SPDX-License-Identifier: GPL-2.0 */ /* * linux/drivers/staging/erofs/compress.h * * Copyright (C) 2019 HUAWEI, Inc. * http://www.huawei.com/ * Created by Gao Xiang <gaoxiang25@huawei.com> */ #ifndef __EROFS_FS_COMPRESS_H #define __EROFS_FS_COMPRESS_H #include "internal.h" enum { Z_EROFS_COMPRESSION_SHIFTED = Z_EROFS_COMPRESSION_MAX, Z_EROFS_COMPRESSION_RUNTIME_MAX }; struct z_erofs_decompress_req { struct super_block *sb; struct page **in, **out; unsigned short pageofs_out; unsigned int inputsize, outputsize; /* indicate the algorithm will be used for decompression */ unsigned int alg; bool inplace_io, partial_decoding; }; /* * - 0x5A110C8D ('sallocated', Z_EROFS_MAPPING_STAGING) - * used to mark temporary allocated pages from other * file/cached pages and NULL mapping pages. */ #define Z_EROFS_MAPPING_STAGING ((void *)0x5A110C8D) /* check if a page is marked as staging */ static inline bool z_erofs_page_is_staging(struct page *page) { return page->mapping == Z_EROFS_MAPPING_STAGING; } static inline bool z_erofs_put_stagingpage(struct list_head *pagepool, struct page *page) { if (!z_erofs_page_is_staging(page)) return false; /* staging pages should not be used by others at the same time */ if (page_ref_count(page) > 1) put_page(page); else list_add(&page->lru, pagepool); return true; } int z_erofs_decompress(struct z_erofs_decompress_req *rq, struct list_head *pagepool); #endif