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-rw-r--r--kernel/arch/x86/xen/xen-head.S123
1 files changed, 123 insertions, 0 deletions
diff --git a/kernel/arch/x86/xen/xen-head.S b/kernel/arch/x86/xen/xen-head.S
new file mode 100644
index 000000000..8afdfccf6
--- /dev/null
+++ b/kernel/arch/x86/xen/xen-head.S
@@ -0,0 +1,123 @@
+/* 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/page_types.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_PVH
+#define PVH_FEATURES_STR "|writable_descriptor_tables|auto_translated_physmap|supervisor_mode_kernel"
+/* Note the lack of 'hvm_callback_vector'. Older hypervisor will
+ * balk at this being part of XEN_ELFNOTE_FEATURES, so we put it in
+ * XEN_ELFNOTE_SUPPORTED_FEATURES which older hypervisors will ignore.
+ */
+#define PVH_FEATURES ((1 << XENFEAT_writable_page_tables) | \
+ (1 << XENFEAT_auto_translated_physmap) | \
+ (1 << XENFEAT_supervisor_mode_kernel) | \
+ (1 << XENFEAT_hvm_callback_vector))
+/* The XENFEAT_writable_page_tables is not stricly neccessary as we set that
+ * up regardless whether this CONFIG option is enabled or not, but it
+ * clarifies what the right flags need to be.
+ */
+#else
+#define PVH_FEATURES_STR ""
+#define PVH_FEATURES (0)
+#endif
+
+ __INIT
+ENTRY(startup_xen)
+ cld
+#ifdef CONFIG_X86_32
+ mov %esi,xen_start_info
+ mov $init_thread_union+THREAD_SIZE,%esp
+#else
+ mov %rsi,xen_start_info
+ mov $init_thread_union+THREAD_SIZE,%rsp
+#endif
+ jmp xen_start_kernel
+
+ __FINIT
+
+#ifdef CONFIG_XEN_PVH
+/*
+ * xen_pvh_early_cpu_init() - early PVH VCPU initialization
+ * @cpu: this cpu number (%rdi)
+ * @entry: true if this is a secondary vcpu coming up on this entry
+ * point, false if this is the boot CPU being initialized for
+ * the first time (%rsi)
+ *
+ * Note: This is called as a function on the boot CPU, and is the entry point
+ * on the secondary CPU.
+ */
+ENTRY(xen_pvh_early_cpu_init)
+ mov %rsi, %r11
+
+ /* Gather features to see if NX implemented. */
+ mov $0x80000001, %eax
+ cpuid
+ mov %edx, %esi
+
+ mov $MSR_EFER, %ecx
+ rdmsr
+ bts $_EFER_SCE, %eax
+
+ bt $20, %esi
+ jnc 1f /* No NX, skip setting it */
+ bts $_EFER_NX, %eax
+1: wrmsr
+#ifdef CONFIG_SMP
+ cmp $0, %r11b
+ jne cpu_bringup_and_idle
+#endif
+ ret
+
+#endif /* CONFIG_XEN_PVH */
+
+.pushsection .text
+ .balign PAGE_SIZE
+ENTRY(hypercall_page)
+ .skip PAGE_SIZE
+
+#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
+
+.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)
+#endif
+ ELFNOTE(Xen, XEN_ELFNOTE_ENTRY, _ASM_PTR startup_xen)
+ ELFNOTE(Xen, XEN_ELFNOTE_HYPERCALL_PAGE, _ASM_PTR hypercall_page)
+ ELFNOTE(Xen, XEN_ELFNOTE_FEATURES, .ascii "!writable_page_tables|pae_pgdir_above_4gb"; .asciz PVH_FEATURES_STR)
+ ELFNOTE(Xen, XEN_ELFNOTE_SUPPORTED_FEATURES, .long (PVH_FEATURES) |
+ (1 << XENFEAT_writable_page_tables) |
+ (1 << XENFEAT_dom0))
+ 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 */