diff options
Diffstat (limited to 'drivers/staging/ramzswap/ramzswap_drv.h')
| -rw-r--r-- | drivers/staging/ramzswap/ramzswap_drv.h | 167 |
1 files changed, 0 insertions, 167 deletions
diff --git a/drivers/staging/ramzswap/ramzswap_drv.h b/drivers/staging/ramzswap/ramzswap_drv.h deleted file mode 100644 index 63c30420df21..000000000000 --- a/drivers/staging/ramzswap/ramzswap_drv.h +++ /dev/null @@ -1,167 +0,0 @@ -/* - * Compressed RAM based swap device - * - * Copyright (C) 2008, 2009, 2010 Nitin Gupta - * - * 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 - * - * Project home: http://compcache.googlecode.com - */ - -#ifndef _RAMZSWAP_DRV_H_ -#define _RAMZSWAP_DRV_H_ - -#include <linux/spinlock.h> -#include <linux/mutex.h> - -#include "ramzswap_ioctl.h" -#include "xvmalloc.h" - -/* - * Some arbitrary value. This is just to catch - * invalid value for num_devices module parameter. - */ -static const unsigned max_num_devices = 32; - -/* - * Stored at beginning of each compressed object. - * - * It stores back-reference to table entry which points to this - * object. This is required to support memory defragmentation. - */ -struct zobj_header { -#if 0 - u32 table_idx; -#endif -}; - -/*-- Configurable parameters */ - -/* Default ramzswap disk size: 25% of total RAM */ -static const unsigned default_disksize_perc_ram = 25; - -/* - * Pages that compress to size greater than this are stored - * uncompressed in memory. - */ -static const unsigned max_zpage_size = PAGE_SIZE / 4 * 3; - -/* - * NOTE: max_zpage_size must be less than or equal to: - * XV_MAX_ALLOC_SIZE - sizeof(struct zobj_header) - * otherwise, xv_malloc() would always return failure. - */ - -/*-- End of configurable params */ - -#define SECTOR_SHIFT 9 -#define SECTOR_SIZE (1 << SECTOR_SHIFT) -#define SECTORS_PER_PAGE_SHIFT (PAGE_SHIFT - SECTOR_SHIFT) -#define SECTORS_PER_PAGE (1 << SECTORS_PER_PAGE_SHIFT) - -/* Flags for ramzswap pages (table[page_no].flags) */ -enum rzs_pageflags { - /* Page is stored uncompressed */ - RZS_UNCOMPRESSED, - - /* Page consists entirely of zeros */ - RZS_ZERO, - - __NR_RZS_PAGEFLAGS, -}; - -/*-- Data structures */ - -/* - * Allocated for each swap slot, indexed by page no. - * These table entries must fit exactly in a page. - */ -struct table { - struct page *page; - u16 offset; - u8 count; /* object ref count (not yet used) */ - u8 flags; -} __attribute__((aligned(4))); - -struct ramzswap_stats { - /* basic stats */ - size_t compr_size; /* compressed size of pages stored - - * needed to enforce memlimit */ - /* more stats */ -#if defined(CONFIG_RAMZSWAP_STATS) - u64 num_reads; /* failed + successful */ - u64 num_writes; /* --do-- */ - u64 failed_reads; /* should NEVER! happen */ - u64 failed_writes; /* can happen when memory is too low */ - u64 invalid_io; /* non-swap I/O requests */ - u64 notify_free; /* no. of swap slot free notifications */ - u32 pages_zero; /* no. of zero filled pages */ - u32 pages_stored; /* no. of pages currently stored */ - u32 good_compress; /* % of pages with compression ratio<=50% */ - u32 pages_expand; /* % of incompressible pages */ -#endif -}; - -struct ramzswap { - struct xv_pool *mem_pool; - void *compress_workmem; - void *compress_buffer; - struct table *table; - spinlock_t stat64_lock; /* protect 64-bit stats */ - struct mutex lock; - struct request_queue *queue; - struct gendisk *disk; - int init_done; - /* - * This is limit on amount of *uncompressed* worth of data - * we can hold. When backing swap device is provided, it is - * set equal to device size. - */ - size_t disksize; /* bytes */ - - struct ramzswap_stats stats; -}; - -/*-- */ - -/* Debugging and Stats */ -#if defined(CONFIG_RAMZSWAP_STATS) -static void rzs_stat_inc(u32 *v) -{ - *v = *v + 1; -} - -static void rzs_stat_dec(u32 *v) -{ - *v = *v - 1; -} - -static void rzs_stat64_inc(struct ramzswap *rzs, u64 *v) -{ - spin_lock(&rzs->stat64_lock); - *v = *v + 1; - spin_unlock(&rzs->stat64_lock); -} - -static u64 rzs_stat64_read(struct ramzswap *rzs, u64 *v) -{ - u64 val; - - spin_lock(&rzs->stat64_lock); - val = *v; - spin_unlock(&rzs->stat64_lock); - - return val; -} -#else -#define rzs_stat_inc(v) -#define rzs_stat_dec(v) -#define rzs_stat64_inc(r, v) -#define rzs_stat64_read(r, v) -#endif /* CONFIG_RAMZSWAP_STATS */ - -#endif |