2 * Compressed RAM based swap device
4 * Copyright (C) 2008, 2009, 2010 Nitin Gupta
6 * This code is released using a dual license strategy: BSD/GPL
7 * You can choose the licence that better fits your requirements.
9 * Released under the terms of 3-clause BSD License
10 * Released under the terms of GNU General Public License Version 2.0
12 * Project home: http://compcache.googlecode.com
15 #ifndef _RAMZSWAP_IOCTL_H_
16 #define _RAMZSWAP_IOCTL_H_
18 struct ramzswap_ioctl_stats {
19 u64 disksize; /* user specified or equal to backing swap
20 * size (if present) */
21 u64 num_reads; /* failed + successful */
22 u64 num_writes; /* --do-- */
23 u64 failed_reads; /* should NEVER! happen */
24 u64 failed_writes; /* can happen when memory is too low */
25 u64 invalid_io; /* non-swap I/O requests */
26 u64 notify_free; /* no. of swap slot free notifications */
27 u32 pages_zero; /* no. of zero filled pages */
28 u32 good_compress_pct; /* no. of pages with compression ratio<=50% */
29 u32 pages_expand_pct; /* no. of incompressible pages */
35 } __attribute__ ((packed, aligned(4)));
37 #define RZSIO_SET_DISKSIZE_KB _IOW('z', 0, size_t)
38 #define RZSIO_GET_STATS _IOR('z', 1, struct ramzswap_ioctl_stats)
39 #define RZSIO_INIT _IO('z', 2)
40 #define RZSIO_RESET _IO('z', 3)