linux/drivers/block/zram/zram_drv.h

/*
 * Compressed RAM block device
 *
 * Copyright (C) 2008, 2009, 2010  Nitin Gupta
 *               2012, 2013 Minchan Kim
 *
 * This code is released using a dual license strategy: BSD/GPL
 * You can choose the licence that better fits your requirements.
 *
 * Released under the terms of 3-clause BSD License
 * Released under the terms of GNU General Public License Version 2.0
 *
 */

#ifndef _ZRAM_DRV_H_
#define _ZRAM_DRV_H_

#include <linux/rwsem.h>
#include <linux/zsmalloc.h>
#include <linux/crypto.h>

#include "zcomp.h"

#define SECTORS_PER_PAGE_SHIFT …
#define SECTORS_PER_PAGE …
#define ZRAM_LOGICAL_BLOCK_SHIFT …
#define ZRAM_LOGICAL_BLOCK_SIZE …
#define ZRAM_SECTOR_PER_LOGICAL_BLOCK …


/*
 * ZRAM is mainly used for memory efficiency so we want to keep memory
 * footprint small and thus squeeze size and zram pageflags into a flags
 * member. The lower ZRAM_FLAG_SHIFT bits is for object size (excluding
 * header), which cannot be larger than PAGE_SIZE (requiring PAGE_SHIFT
 * bits), the higher bits are for zram_pageflags.
 *
 * We use BUILD_BUG_ON() to make sure that zram pageflags don't overflow.
 */
#define ZRAM_FLAG_SHIFT …

/* Only 2 bits are allowed for comp priority index */
#define ZRAM_COMP_PRIORITY_MASK …

/* Flags for zram pages (table[page_no].flags) */
enum zram_pageflags { … };

/*-- Data structures */

/* Allocated for each disk page */
struct zram_table_entry { … };

struct zram_stats { … };

#ifdef CONFIG_ZRAM_MULTI_COMP
#define ZRAM_PRIMARY_COMP …
#define ZRAM_SECONDARY_COMP …
#define ZRAM_MAX_COMPS …
#else
#define ZRAM_PRIMARY_COMP …
#define ZRAM_SECONDARY_COMP …
#define ZRAM_MAX_COMPS …
#endif

struct zram { … };
#endif