1 /* SPDX-License-Identifier: GPL-2.0-or-later */ 2 3 #ifndef _ZCOMP_H_ 4 #define _ZCOMP_H_ 5 6 #include <linux/mutex.h> 7 8 #define ZCOMP_PARAM_NOT_SET INT_MIN 9 10 struct deflate_params { 11 s32 winbits; 12 }; 13 14 /* 15 * Immutable driver (backend) parameters. The driver may attach private 16 * data to it (e.g. driver representation of the dictionary, etc.). 17 * 18 * This data is kept per-comp and is shared among execution contexts. 19 */ 20 struct zcomp_params { 21 void *dict; 22 size_t dict_sz; 23 s32 level; 24 union { 25 struct deflate_params deflate; 26 }; 27 28 void *drv_data; 29 }; 30 31 /* 32 * Run-time driver context - scratch buffers, etc. It is modified during 33 * request execution (compression/decompression), cannot be shared, so 34 * it's in per-CPU area. 35 */ 36 struct zcomp_ctx { 37 void *context; 38 }; 39 40 struct zcomp_strm { 41 struct mutex lock; 42 /* compression buffer */ 43 void *buffer; 44 /* local copy of handle memory */ 45 void *local_copy; 46 struct zcomp_ctx ctx; 47 }; 48 49 struct zcomp_req { 50 const unsigned char *src; 51 const size_t src_len; 52 53 unsigned char *dst; 54 size_t dst_len; 55 }; 56 57 struct zcomp_ops { 58 int (*compress)(struct zcomp_params *params, struct zcomp_ctx *ctx, 59 struct zcomp_req *req); 60 int (*decompress)(struct zcomp_params *params, struct zcomp_ctx *ctx, 61 struct zcomp_req *req); 62 63 int (*create_ctx)(struct zcomp_params *params, struct zcomp_ctx *ctx); 64 void (*destroy_ctx)(struct zcomp_ctx *ctx); 65 66 int (*setup_params)(struct zcomp_params *params); 67 void (*release_params)(struct zcomp_params *params); 68 69 const char *name; 70 }; 71 72 /* dynamic per-device compression frontend */ 73 struct zcomp { 74 struct zcomp_strm __percpu *stream; 75 const struct zcomp_ops *ops; 76 struct zcomp_params *params; 77 struct hlist_node node; 78 }; 79 80 int zcomp_cpu_up_prepare(unsigned int cpu, struct hlist_node *node); 81 int zcomp_cpu_dead(unsigned int cpu, struct hlist_node *node); 82 ssize_t zcomp_available_show(const char *comp, char *buf, ssize_t at); 83 bool zcomp_available_algorithm(const char *comp); 84 85 struct zcomp *zcomp_create(const char *alg, struct zcomp_params *params); 86 void zcomp_destroy(struct zcomp *comp); 87 88 struct zcomp_strm *zcomp_stream_get(struct zcomp *comp); 89 void zcomp_stream_put(struct zcomp_strm *zstrm); 90 91 int zcomp_compress(struct zcomp *comp, struct zcomp_strm *zstrm, 92 const void *src, unsigned int *dst_len); 93 int zcomp_decompress(struct zcomp *comp, struct zcomp_strm *zstrm, 94 const void *src, unsigned int src_len, void *dst); 95 96 #endif /* _ZCOMP_H_ */ 97