fs/jffs2/compr.h

   1 /*
   2  * JFFS2 -- Journalling Flash File System, Version 2.
   3  *
   4  * Copyright © 2004   Ferenc Havasi <havasi@inf.u-szeged.hu>,
   5  *                    University of Szeged, Hungary
   6  * Copyright © 2004-2010 David Woodhouse <dwmw2@infradead.org>
   7  *
   8  * For licensing information, see the file 'LICENCE' in this directory.
   9  *
  10  */
  11
  12 #ifndef __JFFS2_COMPR_H__
  13 #define __JFFS2_COMPR_H__
  14
  15 #include <linux/kernel.h>
  16 #include <linux/vmalloc.h>
  17 #include <linux/list.h>
  18 #include <linux/types.h>
  19 #include <linux/string.h>
  20 #include <linux/slab.h>
  21 #include <linux/errno.h>
  22 #include <linux/fs.h>
  23 #include <linux/jffs2.h>
  24 #include "jffs2_fs_i.h"
  25 #include "jffs2_fs_sb.h"
  26 #include "nodelist.h"
  27
  28 #define JFFS2_RUBINMIPS_PRIORITY 10
  29 #define JFFS2_DYNRUBIN_PRIORITY  20
  30 #define JFFS2_LZARI_PRIORITY     30
  31 #define JFFS2_RTIME_PRIORITY     50
  32 #define JFFS2_ZLIB_PRIORITY      60
  33 #define JFFS2_LZO_PRIORITY       80
  34
  35
  36 #define JFFS2_RUBINMIPS_DISABLED /* RUBINs will be used only */
  37 #define JFFS2_DYNRUBIN_DISABLED  /*        for decompression */
  38
  39 #define JFFS2_COMPR_MODE_NONE       0
  40 #define JFFS2_COMPR_MODE_PRIORITY   1
  41 #define JFFS2_COMPR_MODE_SIZE       2
  42 #define JFFS2_COMPR_MODE_FAVOURLZO  3
  43 #define JFFS2_COMPR_MODE_FORCELZO   4
  44 #define JFFS2_COMPR_MODE_FORCEZLIB  5
  45
  46 #define FAVOUR_LZO_PERCENT 80
  47
  48 struct jffs2_compressor {
  49         struct list_head list;
  50         int priority;                   /* used by prirority comr. mode */
  51         char *name;
  52         char compr;                     /* JFFS2_COMPR_XXX */
  53         int (*compress)(unsigned char *data_in, unsigned char *cpage_out,
  54                         uint32_t *srclen, uint32_t *destlen);
  55         int (*decompress)(unsigned char *cdata_in, unsigned char *data_out,
  56                           uint32_t cdatalen, uint32_t datalen);
  57         int usecount;
  58         int disabled;           /* if set the compressor won't compress */
  59         unsigned char *compr_buf;       /* used by size compr. mode */
  60         uint32_t compr_buf_size;        /* used by size compr. mode */
  61         uint32_t stat_compr_orig_size;
  62         uint32_t stat_compr_new_size;
  63         uint32_t stat_compr_blocks;
  64         uint32_t stat_decompr_blocks;
  65 };
  66
  67 int jffs2_register_compressor(struct jffs2_compressor *comp);
  68 int jffs2_unregister_compressor(struct jffs2_compressor *comp);
  69
  70 int jffs2_compressors_init(void);
  71 int jffs2_compressors_exit(void);
  72
  73 uint16_t jffs2_compress(struct jffs2_sb_info *c, struct jffs2_inode_info *f,
  74                         unsigned char *data_in, unsigned char **cpage_out,
  75                         uint32_t *datalen, uint32_t *cdatalen);
  76
  77 int jffs2_decompress(struct jffs2_sb_info *c, struct jffs2_inode_info *f,
  78                      uint16_t comprtype, unsigned char *cdata_in,
  79                      unsigned char *data_out, uint32_t cdatalen, uint32_t datalen);
  80
  81 void jffs2_free_comprbuf(unsigned char *comprbuf, unsigned char *orig);
  82
  83 /* Compressor modules */
  84 /* These functions will be called by jffs2_compressors_init/exit */
  85
  86 #ifdef CONFIG_JFFS2_RUBIN
  87 int jffs2_rubinmips_init(void);
  88 void jffs2_rubinmips_exit(void);
  89 int jffs2_dynrubin_init(void);
  90 void jffs2_dynrubin_exit(void);
  91 #else
  92 static inline int jffs2_rubinmips_init(void) { return 0; }
  93 static inline void jffs2_rubinmips_exit(void) {}
  94 static inline int jffs2_dynrubin_init(void) { return 0; }
  95 static inline void jffs2_dynrubin_exit(void) {}
  96 #endif
  97 #ifdef CONFIG_JFFS2_RTIME
  98 extern int jffs2_rtime_init(void);
  99 extern void jffs2_rtime_exit(void);
 100 #else
 101 static inline int jffs2_rtime_init(void) { return 0; }
 102 static inline void jffs2_rtime_exit(void) {}
 103 #endif
 104 #ifdef CONFIG_JFFS2_ZLIB
 105 extern int jffs2_zlib_init(void);
 106 extern void jffs2_zlib_exit(void);
 107 #else
 108 static inline int jffs2_zlib_init(void) { return 0; }
 109 static inline void jffs2_zlib_exit(void) {}
 110 #endif
 111 #ifdef CONFIG_JFFS2_LZO
 112 extern int jffs2_lzo_init(void);
 113 extern void jffs2_lzo_exit(void);
 114 #else
 115 static inline int jffs2_lzo_init(void) { return 0; }
 116 static inline void jffs2_lzo_exit(void) {}
 117 #endif
 118
 119 #endif /* __JFFS2_COMPR_H__ */