linux/drivers/xen/unpopulated-alloc.c

// SPDX-License-Identifier: GPL-2.0
#include <linux/errno.h>
#include <linux/gfp.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/memremap.h>
#include <linux/slab.h>

#include <asm/page.h>

#include <xen/balloon.h>
#include <xen/page.h>
#include <xen/xen.h>

static DEFINE_MUTEX(list_lock);
static struct page *page_list;
static unsigned int list_count;

static struct resource *target_resource;

/*
 * If arch is not happy with system "iomem_resource" being used for
 * the region allocation it can provide it's own view by creating specific
 * Xen resource with unused regions of guest physical address space provided
 * by the hypervisor.
 */
int __weak __init arch_xen_unpopulated_init(struct resource **res)
{ … }

static int fill_list(unsigned int nr_pages)
{ … }

/**
 * xen_alloc_unpopulated_pages - alloc unpopulated pages
 * @nr_pages: Number of pages
 * @pages: pages returned
 * @return 0 on success, error otherwise
 */
int xen_alloc_unpopulated_pages(unsigned int nr_pages, struct page **pages)
{ … }
EXPORT_SYMBOL(…);

/**
 * xen_free_unpopulated_pages - return unpopulated pages
 * @nr_pages: Number of pages
 * @pages: pages to return
 */
void xen_free_unpopulated_pages(unsigned int nr_pages, struct page **pages)
{ … }
EXPORT_SYMBOL(…);

static int __init unpopulated_init(void)
{ … }
early_initcall(unpopulated_init);