Commit c4f5cdc5 authored by Don Slutz's avatar Don Slutz Committed by Michael S. Tsirkin
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xen-hvm: Handle machine opt max-ram-below-4g 



This is the xen part of "pc & q35: Add new machine opt max-ram-below-4g"

Note: this machine option cannot be used to increase the amount
of ram below 4G.

Signed-off-by: default avatarDon Slutz <dslutz@verizon.com>
Reviewed-by: default avatarMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: default avatarMichael S. Tsirkin <mst@redhat.com>
parent c87b1520

xen-hvm.c

+23 −12
Original line number Diff line number Diff line
@@ -161,25 +161,36 @@ static void xen_ram_init(ram_addr_t *below_4g_mem_size, 
{

    MemoryRegion *sysmem = get_system_memory();

    ram_addr_t block_len;

    uint64_t user_lowmem = object_property_get_int(qdev_get_machine(),

                                                   PC_MACHINE_MAX_RAM_BELOW_4G,

                                                   &error_abort);



    block_len = ram_size;

    if (ram_size >= HVM_BELOW_4G_RAM_END) {

        /* Xen does not allocate the memory continuously, and keep a hole at

         * HVM_BELOW_4G_MMIO_START of HVM_BELOW_4G_MMIO_LENGTH

    /* Handle the machine opt max-ram-below-4g.  It is basicly doing

     * min(xen limit, user limit).

     */

        block_len += HVM_BELOW_4G_MMIO_LENGTH;

    if (HVM_BELOW_4G_RAM_END <= user_lowmem) {

        user_lowmem = HVM_BELOW_4G_RAM_END;

    }

    memory_region_init_ram(&ram_memory, NULL, "xen.ram", block_len);

    *ram_memory_p = &ram_memory;

    vmstate_register_ram_global(&ram_memory);



    if (ram_size >= HVM_BELOW_4G_RAM_END) {

        *above_4g_mem_size = ram_size - HVM_BELOW_4G_RAM_END;

        *below_4g_mem_size = HVM_BELOW_4G_RAM_END;

    if (ram_size >= user_lowmem) {

        *above_4g_mem_size = ram_size - user_lowmem;

        *below_4g_mem_size = user_lowmem;

    } else {

        *above_4g_mem_size = 0;

        *below_4g_mem_size = ram_size;

    }

    if (!*above_4g_mem_size) {

        block_len = ram_size;

    } else {

        /*

         * Xen does not allocate the memory continuously, it keeps a

         * hole of the size computed above or passed in.

         */

        block_len = (1ULL << 32) + *above_4g_mem_size;

    }

    memory_region_init_ram(&ram_memory, NULL, "xen.ram", block_len);

    *ram_memory_p = &ram_memory;

    vmstate_register_ram_global(&ram_memory);



    memory_region_init_alias(&ram_640k, NULL, "xen.ram.640k",

                             &ram_memory, 0, 0xa0000);