1 /* SPDX-License-Identifier: GPL-2.0-only */ 2 /* 3 * Copyright (C) 2019 HUAWEI, Inc. 4 * https://www.huawei.com/ 5 */ 6 #ifndef __EROFS_FS_COMPRESS_H 7 #define __EROFS_FS_COMPRESS_H 8 9 #include "internal.h" 10 11 struct z_erofs_decompress_req { 12 struct super_block *sb; 13 struct page **in, **out; 14 unsigned int inpages, outpages; 15 unsigned short pageofs_in, pageofs_out; 16 unsigned int inputsize, outputsize; 17 18 unsigned int alg; /* the algorithm for decompression */ 19 bool inplace_io, partial_decoding, fillgaps; 20 gfp_t gfp; /* allocation flags for extra temporary buffers */ 21 }; 22 23 struct z_erofs_decompressor { 24 int (*config)(struct super_block *sb, struct erofs_super_block *dsb, 25 void *data, int size); 26 int (*decompress)(struct z_erofs_decompress_req *rq, 27 struct page **pagepool); 28 int (*init)(void); 29 void (*exit)(void); 30 char *name; 31 }; 32 33 #define Z_EROFS_SHORTLIVED_PAGE (-1UL << 2) 34 #define Z_EROFS_PREALLOCATED_FOLIO ((void *)(-2UL << 2)) 35 36 /* 37 * Currently, short-lived pages are pages directly from buddy system 38 * with specific page->private (Z_EROFS_SHORTLIVED_PAGE). 39 * In the future world of Memdescs, it should be type 0 (Misc) memory 40 * which type can be checked with a new helper. 41 */ 42 static inline bool z_erofs_is_shortlived_page(struct page *page) 43 { 44 return page->private == Z_EROFS_SHORTLIVED_PAGE; 45 } 46 47 static inline bool z_erofs_put_shortlivedpage(struct page **pagepool, 48 struct page *page) 49 { 50 if (!z_erofs_is_shortlived_page(page)) 51 return false; 52 erofs_pagepool_add(pagepool, page); 53 return true; 54 } 55 56 extern const struct z_erofs_decompressor z_erofs_lzma_decomp; 57 extern const struct z_erofs_decompressor z_erofs_deflate_decomp; 58 extern const struct z_erofs_decompressor z_erofs_zstd_decomp; 59 extern const struct z_erofs_decompressor *z_erofs_decomp[]; 60 61 struct z_erofs_stream_dctx { 62 struct z_erofs_decompress_req *rq; 63 int no, ni; /* the current {en,de}coded page # */ 64 65 unsigned int avail_out; /* remaining bytes in the decoded buffer */ 66 unsigned int inbuf_pos, inbuf_sz; 67 /* current status of the encoded buffer */ 68 u8 *kin, *kout; /* buffer mapped pointers */ 69 void *bounce; /* bounce buffer for inplace I/Os */ 70 bool bounced; /* is the bounce buffer used now? */ 71 }; 72 73 int z_erofs_stream_switch_bufs(struct z_erofs_stream_dctx *dctx, void **dst, 74 void **src, struct page **pgpl); 75 int z_erofs_fixup_insize(struct z_erofs_decompress_req *rq, const char *padbuf, 76 unsigned int padbufsize); 77 int __init z_erofs_init_decompressor(void); 78 void z_erofs_exit_decompressor(void); 79 int z_erofs_crypto_decompress(struct z_erofs_decompress_req *rq, 80 struct page **pgpl); 81 int z_erofs_crypto_enable_engine(const char *name, int len); 82 #ifdef CONFIG_EROFS_FS_ZIP_ACCEL 83 void z_erofs_crypto_disable_all_engines(void); 84 int z_erofs_crypto_show_engines(char *buf, int size, char sep); 85 #else 86 static inline void z_erofs_crypto_disable_all_engines(void) {} 87 static inline int z_erofs_crypto_show_engines(char *buf, int size, char sep) { return 0; } 88 #endif 89 #endif 90