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 struct scatterlist; 9 10 #define ZCOMP_PARAM_NOT_SET INT_MIN 11 12 struct deflate_params { 13 s32 winbits; 14 }; 15 16 /* 17 * Immutable driver (backend) parameters. The driver may attach private 18 * data to it (e.g. driver representation of the dictionary, etc.). 19 * 20 * This data is kept per-comp and is shared among execution contexts. 21 */ 22 struct zcomp_params { 23 void *dict; 24 size_t dict_sz; 25 s32 level; 26 union { 27 struct deflate_params deflate; 28 }; 29 30 void *drv_data; 31 }; 32 33 /* 34 * Run-time driver context - scratch buffers, etc. It is modified during 35 * request execution (compression/decompression), cannot be shared, so 36 * it's in per-CPU area. 37 */ 38 struct zcomp_ctx { 39 void *context; 40 }; 41 42 struct zcomp_strm { 43 struct mutex lock; 44 /* compression buffer */ 45 void *buffer; 46 /* local copy of handle memory */ 47 void *local_copy; 48 struct zcomp_ctx ctx; 49 }; 50 51 struct zcomp_req { 52 const unsigned char *src; 53 const size_t src_len; 54 55 unsigned char *dst; 56 size_t dst_len; 57 }; 58 59 struct zcomp_ops { 60 int (*compress)(struct zcomp_params *params, struct zcomp_ctx *ctx, 61 struct zcomp_req *req); 62 int (*decompress)(struct zcomp_params *params, struct zcomp_ctx *ctx, 63 struct zcomp_req *req); 64 65 int (*create_ctx)(struct zcomp_params *params, struct zcomp_ctx *ctx); 66 void (*destroy_ctx)(struct zcomp_ctx *ctx); 67 68 int (*setup_params)(struct zcomp_params *params); 69 void (*release_params)(struct zcomp_params *params); 70 71 const char *name; 72 }; 73 74 /* dynamic per-device compression frontend */ 75 struct zcomp { 76 struct zcomp_strm __percpu *stream; 77 const struct zcomp_ops *ops; 78 struct zcomp_params *params; 79 struct hlist_node node; 80 }; 81 82 int zcomp_cpu_up_prepare(unsigned int cpu, struct hlist_node *node); 83 int zcomp_cpu_dead(unsigned int cpu, struct hlist_node *node); 84 ssize_t zcomp_available_show(const char *comp, char *buf, ssize_t at); 85 const char *zcomp_lookup_backend_name(const char *comp); 86 87 struct zcomp *zcomp_create(const char *alg, struct zcomp_params *params); 88 void zcomp_destroy(struct zcomp *comp); 89 90 struct zcomp_strm *zcomp_stream_get(struct zcomp *comp); 91 void zcomp_stream_put(struct zcomp_strm *zstrm); 92 93 int zcomp_compress(struct zcomp *comp, struct zcomp_strm *zstrm, 94 const void *src, unsigned int *dst_len); 95 int zcomp_decompress(struct zcomp *comp, struct zcomp_strm *zstrm, 96 struct scatterlist *sg, unsigned int src_len, void *dst); 97 98 #endif /* _ZCOMP_H_ */ 99