linux-imx

/* Inject a hwpoison memory failure on a arbitrary pfn */

#include <linux/module.h>

#include <linux/debugfs.h>

#include <linux/kernel.h>

#include <linux/mm.h>

#include <linux/swap.h>

#include <linux/pagemap.h>

#include <linux/hugetlb.h>

#include "internal.h"

​

static struct dentry *hwpoison_dir;

​

static int hwpoison_inject(void *data, u64 val)

{

    unsigned long pfn = val;

    struct page *p;

    struct page *hpage;

    int err;

​

    if (!capable(CAP_SYS_ADMIN))

        return -EPERM;

​

    if (!pfn_valid(pfn))

        return -ENXIO;

​

    p = pfn_to_page(pfn);

    hpage = compound_head(p);

    /*

     * This implies unable to support free buddy pages.

     */

    if (!get_hwpoison_page(p))

        return 0;

​

    if (!hwpoison_filter_enable)

        goto inject;

​

    shake_page(hpage, 0);

    /*

     * This implies unable to support non-LRU pages.

     */

    if (!PageLRU(hpage) && !PageHuge(p))

        goto put_out;

​

    /*

     * do a racy check with elevated page count, to make sure PG_hwpoison

     * will only be set for the targeted owner (or on a free page).

     * memory_failure() will redo the check reliably inside page lock.

     */

    err = hwpoison_filter(hpage);

    if (err)

        goto put_out;

​

inject:

    pr_info("Injecting memory failure at pfn %#lx\n", pfn);

    return memory_failure(pfn, MF_COUNT_INCREASED);

put_out:

    put_hwpoison_page(p);

    return 0;

}

​

static int hwpoison_unpoison(void *data, u64 val)

{

    if (!capable(CAP_SYS_ADMIN))