linux-imx

// SPDX-License-Identifier: GPL-2.0-only

/*

 * Xen implementation for transcendent memory (tmem)

 *

 * Copyright (C) 2009-2011 Oracle Corp.  All rights reserved.

 * Author: Dan Magenheimer

 */

​

#define pr_fmt(fmt) "xen:" KBUILD_MODNAME ": " fmt

​

#include <linux/module.h>

#include <linux/kernel.h>

#include <linux/types.h>

#include <linux/init.h>

#include <linux/pagemap.h>

#include <linux/cleancache.h>

#include <linux/frontswap.h>

​

#include <xen/xen.h>

#include <xen/interface/xen.h>

#include <xen/page.h>

#include <asm/xen/hypercall.h>

#include <asm/xen/hypervisor.h>

#include <xen/tmem.h>

​

#ifndef CONFIG_XEN_TMEM_MODULE

bool __read_mostly tmem_enabled = false;

​

static int __init enable_tmem(char *s)

{

    tmem_enabled = true;

    return 1;

}

__setup("tmem", enable_tmem);

#endif

​

#ifdef CONFIG_CLEANCACHE

static bool cleancache __read_mostly = true;

module_param(cleancache, bool, S_IRUGO);

static bool selfballooning __read_mostly = true;

module_param(selfballooning, bool, S_IRUGO);

#endif /* CONFIG_CLEANCACHE */

​

#ifdef CONFIG_FRONTSWAP

static bool frontswap __read_mostly = true;

module_param(frontswap, bool, S_IRUGO);

#else /* CONFIG_FRONTSWAP */

#define frontswap (0)

#endif /* CONFIG_FRONTSWAP */

​

#ifdef CONFIG_XEN_SELFBALLOONING

static bool selfshrinking __read_mostly = true;

module_param(selfshrinking, bool, S_IRUGO);

#endif /* CONFIG_XEN_SELFBALLOONING */

​

#define TMEM_CONTROL               0

#define TMEM_NEW_POOL              1

#define TMEM_DESTROY_POOL          2

#define TMEM_NEW_PAGE              3

#define TMEM_PUT_PAGE              4

#define TMEM_GET_PAGE              5

#define TMEM_FLUSH_PAGE            6

#define TMEM_FLUSH_OBJECT          7

#define TMEM_READ                  8

#define TMEM_WRITE                 9

#define TMEM_XCHG                 10

​

/* Bits for HYPERVISOR_tmem_op(TMEM_NEW_POOL) */

#define TMEM_POOL_PERSIST          1

#define TMEM_POOL_SHARED           2

#define TMEM_POOL_PAGESIZE_SHIFT   4

#define TMEM_VERSION_SHIFT        24

​

​

struct tmem_pool_uuid {

    u64 uuid_lo;

    u64 uuid_hi;

};

​

struct tmem_oid {

    u64 oid[3];

};

​

#define TMEM_POOL_PRIVATE_UUID  { 0, 0 }

​

/* flags for tmem_ops.new_pool */

#define TMEM_POOL_PERSIST          1

#define TMEM_POOL_SHARED           2

​

/* xen tmem foundation ops/hypercalls */

​

static inline int xen_tmem_op(u32 tmem_cmd, u32 tmem_pool, struct tmem_oid oid,