linux-imx

// SPDX-License-Identifier: GPL-2.0

#include <linux/mm.h>

#include <linux/rmap.h>

#include <linux/hugetlb.h>

#include <linux/swap.h>

#include <linux/swapops.h>

​

#include "internal.h"

​

static inline bool not_found(struct page_vma_mapped_walk *pvmw)

{

    page_vma_mapped_walk_done(pvmw);

    return false;

}

​

static bool map_pte(struct page_vma_mapped_walk *pvmw)

{

    pvmw->pte = pte_offset_map(pvmw->pmd, pvmw->address);

    if (!(pvmw->flags & PVMW_SYNC)) {

        if (pvmw->flags & PVMW_MIGRATION) {

            if (!is_swap_pte(*pvmw->pte))

                return false;

        } else {

            /*

             * We get here when we are trying to unmap a private

             * device page from the process address space. Such

             * page is not CPU accessible and thus is mapped as

             * a special swap entry, nonetheless it still does

             * count as a valid regular mapping for the page (and

             * is accounted as such in page maps count).

             *

             * So handle this special case as if it was a normal

             * page mapping ie lock CPU page table and returns

             * true.

             *

             * For more details on device private memory see HMM

             * (include/linux/hmm.h or mm/hmm.c).

             */

            if (is_swap_pte(*pvmw->pte)) {

                swp_entry_t entry;

​

                /* Handle un-addressable ZONE_DEVICE memory */

                entry = pte_to_swp_entry(*pvmw->pte);

                if (!is_device_private_entry(entry))

                    return false;

            } else if (!pte_present(*pvmw->pte))

                return false;

        }

    }

    pvmw->ptl = pte_lockptr(pvmw->vma->vm_mm, pvmw->pmd);

    spin_lock(pvmw->ptl);

    return true;

}

​

static inline bool pfn_in_hpage(struct page *hpage, unsigned long pfn)

{

    unsigned long hpage_pfn = page_to_pfn(hpage);

​

    /* THP can be referenced by any subpage */

    return pfn >= hpage_pfn && pfn - hpage_pfn < hpage_nr_pages(hpage);

}

​

/**