root/sys/amd64/vmm/vmm_mem_machdep.c
/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (c) 2011 NetApp, Inc.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY NETAPP, INC ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL NETAPP, INC OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/sglist.h>
#include <sys/lock.h>
#include <sys/rwlock.h>

#include <vm/vm.h>
#include <vm/vm_param.h>
#include <vm/pmap.h>
#include <vm/vm_extern.h>
#include <vm/vm_map.h>
#include <vm/vm_object.h>
#include <vm/vm_page.h>
#include <vm/vm_pager.h>

#include <machine/md_var.h>

#include "vmm_mem.h"

int
vmm_mmio_alloc(struct vmspace *vmspace, vm_paddr_t gpa, size_t len,
    vm_paddr_t hpa)
{
        struct sglist *sg;
        vm_object_t obj;
        int error;

        if (gpa + len < gpa || hpa + len < hpa || (gpa & PAGE_MASK) != 0 ||
            (hpa & PAGE_MASK) != 0 || (len & PAGE_MASK) != 0)
                return (EINVAL);

        sg = sglist_alloc(1, M_WAITOK);
        error = sglist_append_phys(sg, hpa, len);
        KASSERT(error == 0, ("error %d appending physaddr to sglist", error));

        obj = vm_pager_allocate(OBJT_SG, sg, len, VM_PROT_RW, 0, NULL);
        if (obj == NULL)
                return (ENOMEM);

        /*
         * VT-x ignores the MTRR settings when figuring out the memory type for
         * translations obtained through EPT.
         *
         * Therefore we explicitly force the pages provided by this object to be
         * mapped as uncacheable.
         */
        VM_OBJECT_WLOCK(obj);
        error = vm_object_set_memattr(obj, VM_MEMATTR_UNCACHEABLE);
        VM_OBJECT_WUNLOCK(obj);
        if (error != KERN_SUCCESS)
                panic("vmm_mmio_alloc: vm_object_set_memattr error %d", error);

        vm_map_lock(&vmspace->vm_map);
        error = vm_map_insert(&vmspace->vm_map, obj, 0, gpa, gpa + len,
            VM_PROT_RW, VM_PROT_RW, 0);
        vm_map_unlock(&vmspace->vm_map);
        if (error != KERN_SUCCESS) {
                error = vm_mmap_to_errno(error);
                vm_object_deallocate(obj);
        } else {
                error = 0;
        }

        /*
         * Drop the reference on the sglist.
         *
         * If the scatter/gather object was successfully allocated then it
         * has incremented the reference count on the sglist. Dropping the
         * initial reference count ensures that the sglist will be freed
         * when the object is deallocated.
         *
         * If the object could not be allocated then we end up freeing the
         * sglist.
         */
        sglist_free(sg);

        return (error);
}

void
vmm_mmio_free(struct vmspace *vmspace, vm_paddr_t gpa, size_t len)
{

        vm_map_remove(&vmspace->vm_map, gpa, gpa + len);
}

vm_paddr_t
vmm_mem_maxaddr(void)
{

        return (ptoa(Maxmem));
}