linux-imx

#include <linux/kasan.h>

#include <linux/memory_hotplug.h>

#include <linux/mm.h>

#include <linux/pfn_t.h>

#include <linux/swap.h>

#include <linux/swapops.h>

#include <linux/types.h>

#include <linux/wait_bit.h>

#include <linux/xarray.h>

​

static DEFINE_XARRAY(pgmap_array);

#define SECTION_MASK ~((1UL << PA_SECTION_SHIFT) - 1)

#define SECTION_SIZE (1UL << PA_SECTION_SHIFT)

​

#if IS_ENABLED(CONFIG_DEVICE_PRIVATE)

vm_fault_t device_private_entry_fault(struct vm_area_struct *vma,

               unsigned long addr,

               swp_entry_t entry,

               unsigned int flags,

               pmd_t *pmdp)

{

    struct page *page = device_private_entry_to_page(entry);

​

    /*

     * The page_fault() callback must migrate page back to system memory

     * so that CPU can access it. This might fail for various reasons

     * (device issue, device was unsafely unplugged, ...). When such

     * error conditions happen, the callback must return VM_FAULT_SIGBUS.

     *

     * Note that because memory cgroup charges are accounted to the device

     * memory, this should never fail because of memory restrictions (but

     * allocation of regular system page might still fail because we are

     * out of memory).

     *

     * There is a more in-depth description of what that callback can and

     * cannot do, in include/linux/memremap.h

     */

}

EXPORT_SYMBOL(device_private_entry_fault);

#endif /* CONFIG_DEVICE_PRIVATE */

​

static void pgmap_array_delete(struct resource *res)

{

    xa_store_range(&pgmap_array, PHYS_PFN(res->start), PHYS_PFN(res->end),

            NULL, GFP_KERNEL);

    synchronize_rcu();

}