|  | /* SPDX-License-Identifier: GPL-2.0 */ | 
|  | /* Xen-specific pieces of head.S, intended to be included in the right | 
|  | place in head.S */ | 
|  |  | 
|  | #ifdef CONFIG_XEN | 
|  |  | 
|  | #include <linux/elfnote.h> | 
|  | #include <linux/init.h> | 
|  |  | 
|  | #include <asm/boot.h> | 
|  | #include <asm/asm.h> | 
|  | #include <asm/msr.h> | 
|  | #include <asm/page_types.h> | 
|  | #include <asm/percpu.h> | 
|  | #include <asm/unwind_hints.h> | 
|  |  | 
|  | #include <xen/interface/elfnote.h> | 
|  | #include <xen/interface/features.h> | 
|  | #include <xen/interface/xen.h> | 
|  | #include <xen/interface/xen-mca.h> | 
|  | #include <asm/xen/interface.h> | 
|  |  | 
|  | #ifdef CONFIG_XEN_PV | 
|  | __INIT | 
|  | ENTRY(startup_xen) | 
|  | UNWIND_HINT_EMPTY | 
|  | cld | 
|  |  | 
|  | /* Clear .bss */ | 
|  | xor %eax,%eax | 
|  | mov $__bss_start, %_ASM_DI | 
|  | mov $__bss_stop, %_ASM_CX | 
|  | sub %_ASM_DI, %_ASM_CX | 
|  | shr $__ASM_SEL(2, 3), %_ASM_CX | 
|  | rep __ASM_SIZE(stos) | 
|  |  | 
|  | mov %_ASM_SI, xen_start_info | 
|  | mov $init_thread_union+THREAD_SIZE, %_ASM_SP | 
|  |  | 
|  | #ifdef CONFIG_X86_64 | 
|  | /* Set up %gs. | 
|  | * | 
|  | * The base of %gs always points to the bottom of the irqstack | 
|  | * union.  If the stack protector canary is enabled, it is | 
|  | * located at %gs:40.  Note that, on SMP, the boot cpu uses | 
|  | * init data section till per cpu areas are set up. | 
|  | */ | 
|  | movl	$MSR_GS_BASE,%ecx | 
|  | movq	$INIT_PER_CPU_VAR(irq_stack_union),%rax | 
|  | cdq | 
|  | wrmsr | 
|  | #endif | 
|  |  | 
|  | jmp xen_start_kernel | 
|  | END(startup_xen) | 
|  | __FINIT | 
|  | #endif | 
|  |  | 
|  | .pushsection .text | 
|  | .balign PAGE_SIZE | 
|  | ENTRY(hypercall_page) | 
|  | .rept (PAGE_SIZE / 32) | 
|  | UNWIND_HINT_EMPTY | 
|  | .skip 32 | 
|  | .endr | 
|  |  | 
|  | #define HYPERCALL(n) \ | 
|  | .equ xen_hypercall_##n, hypercall_page + __HYPERVISOR_##n * 32; \ | 
|  | .type xen_hypercall_##n, @function; .size xen_hypercall_##n, 32 | 
|  | #include <asm/xen-hypercalls.h> | 
|  | #undef HYPERCALL | 
|  | END(hypercall_page) | 
|  | .popsection | 
|  |  | 
|  | ELFNOTE(Xen, XEN_ELFNOTE_GUEST_OS,       .asciz "linux") | 
|  | ELFNOTE(Xen, XEN_ELFNOTE_GUEST_VERSION,  .asciz "2.6") | 
|  | ELFNOTE(Xen, XEN_ELFNOTE_XEN_VERSION,    .asciz "xen-3.0") | 
|  | #ifdef CONFIG_X86_32 | 
|  | ELFNOTE(Xen, XEN_ELFNOTE_VIRT_BASE,      _ASM_PTR __PAGE_OFFSET) | 
|  | #else | 
|  | ELFNOTE(Xen, XEN_ELFNOTE_VIRT_BASE,      _ASM_PTR __START_KERNEL_map) | 
|  | /* Map the p2m table to a 512GB-aligned user address. */ | 
|  | ELFNOTE(Xen, XEN_ELFNOTE_INIT_P2M,       .quad (PUD_SIZE * PTRS_PER_PUD)) | 
|  | #endif | 
|  | #ifdef CONFIG_XEN_PV | 
|  | ELFNOTE(Xen, XEN_ELFNOTE_ENTRY,          _ASM_PTR startup_xen) | 
|  | #endif | 
|  | ELFNOTE(Xen, XEN_ELFNOTE_HYPERCALL_PAGE, _ASM_PTR hypercall_page) | 
|  | ELFNOTE(Xen, XEN_ELFNOTE_FEATURES, | 
|  | .ascii "!writable_page_tables|pae_pgdir_above_4gb") | 
|  | ELFNOTE(Xen, XEN_ELFNOTE_SUPPORTED_FEATURES, | 
|  | .long (1 << XENFEAT_writable_page_tables) |       \ | 
|  | (1 << XENFEAT_dom0) |                       \ | 
|  | (1 << XENFEAT_linux_rsdp_unrestricted)) | 
|  | ELFNOTE(Xen, XEN_ELFNOTE_PAE_MODE,       .asciz "yes") | 
|  | ELFNOTE(Xen, XEN_ELFNOTE_LOADER,         .asciz "generic") | 
|  | ELFNOTE(Xen, XEN_ELFNOTE_L1_MFN_VALID, | 
|  | .quad _PAGE_PRESENT; .quad _PAGE_PRESENT) | 
|  | ELFNOTE(Xen, XEN_ELFNOTE_SUSPEND_CANCEL, .long 1) | 
|  | ELFNOTE(Xen, XEN_ELFNOTE_MOD_START_PFN,  .long 1) | 
|  | ELFNOTE(Xen, XEN_ELFNOTE_HV_START_LOW,   _ASM_PTR __HYPERVISOR_VIRT_START) | 
|  | ELFNOTE(Xen, XEN_ELFNOTE_PADDR_OFFSET,   _ASM_PTR 0) | 
|  |  | 
|  | #endif /*CONFIG_XEN */ |