drivers/staging/ramzswap/ramzswap_ioctl.h

   1 /*
   2  * Compressed RAM based swap device
   3  *
   4  * Copyright (C) 2008, 2009  Nitin Gupta
   5  *
   6  * This code is released using a dual license strategy: BSD/GPL
   7  * You can choose the licence that better fits your requirements.
   8  *
   9  * Released under the terms of 3-clause BSD License
  10  * Released under the terms of GNU General Public License Version 2.0
  11  *
  12  * Project home: http://compcache.googlecode.com
  13  */
  14
  15 #ifndef _RAMZSWAP_IOCTL_H_
  16 #define _RAMZSWAP_IOCTL_H_
  17
  18 #define MAX_SWAP_NAME_LEN 128
  19
  20 struct ramzswap_ioctl_stats {
  21         char backing_swap_name[MAX_SWAP_NAME_LEN];
  22         u64 memlimit;           /* only applicable if backing swap present */
  23         u64 disksize;           /* user specified or equal to backing swap
  24                                  * size (if present) */
  25         u64 num_reads;          /* failed + successful */
  26         u64 num_writes;         /* --do-- */
  27         u64 failed_reads;       /* can happen when memory is too low */
  28         u64 failed_writes;      /* should NEVER! happen */
  29         u64 invalid_io;         /* non-swap I/O requests */
  30         u32 pages_zero;         /* no. of zero filled pages */
  31         u32 good_compress_pct;  /* no. of pages with compression ratio<=50% */
  32         u32 pages_expand_pct;   /* no. of incompressible pages */
  33         u32 pages_stored;
  34         u32 pages_used;
  35         u64 orig_data_size;
  36         u64 compr_data_size;
  37         u64 mem_used_total;
  38         u64 bdev_num_reads;     /* no. of reads on backing dev */
  39         u64 bdev_num_writes;    /* no. of writes on backing dev */
  40 } __attribute__ ((packed, aligned(4)));
  41
  42 #define RZSIO_SET_DISKSIZE_KB   _IOW('z', 0, size_t)
  43 #define RZSIO_SET_MEMLIMIT_KB   _IOW('z', 1, size_t)
  44 #define RZSIO_SET_BACKING_SWAP  _IOW('z', 2, unsigned char[MAX_SWAP_NAME_LEN])
  45 #define RZSIO_GET_STATS         _IOR('z', 3, struct ramzswap_ioctl_stats)
  46 #define RZSIO_INIT              _IO('z', 4)
  47 #define RZSIO_RESET             _IO('z', 5)
  48
  49 #endif