[PATCH 14/15] x86_64 patching functions

Glauber de Oliveira Costa
2007-12-20T20:13:22Z

Like i386, x86_64 also need to include its own patching function.
(Well, if you're not in a hurry, and don't care about speed, you don't
really _need_ ;-))

So here they are. Not much different in essence from i386

Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com>
---
arch/x86/kernel/Makefile_64 | 1 +
arch/x86/kernel/paravirt_patch_64.c | 56 +++++++++++++++++++++++++++++++++++
2 files changed, 57 insertions(+), 0 deletions(-)
create mode 100644 arch/x86/kernel/paravirt_patch_64.c

Index: linux-2.6-x86/arch/x86/kernel/Makefile_64
===================================================================
--- linux-2.6-x86.orig/arch/x86/kernel/Makefile_64 2007-12-20 19:05:52.000000000 -0800
+++ linux-2.6-x86/arch/x86/kernel/Makefile_64 2007-12-20 19:08:14.000000000 -0800
@@ -41,6 +41,7 @@
obj-$(CONFIG_K8_NB) += k8.o
obj-$(CONFIG_AUDIT) += audit_64.o
obj-$(CONFIG_EFI) += efi.o efi_64.o efi_stub_64.o
+obj-$(CONFIG_PARAVIRT) += paravirt.o paravirt_patch_64.o

obj-$(CONFIG_MODULES) += module_64.o
obj-$(CONFIG_PCI) += early-quirks.o
Index: linux-2.6-x86/arch/x86/kernel/paravirt_patch_64.c
===================================================================
--- /dev/null 1970-01-01 00:00:00.000000000 +0000
+++ linux-2.6-x86/arch/x86/kernel/paravirt_patch_64.c 2007-12-20 19:08:14.000000000 -0800
@@ -0,0 +1,56 @@
+#include <asm/paravirt.h>
+#include <asm/asm-offsets.h>
+
+DEF_NATIVE(pv_irq_ops, irq_disable, "cli");
+DEF_NATIVE(pv_irq_ops, irq_enable, "sti");
+DEF_NATIVE(pv_irq_ops, restore_fl, "pushq %rdi; popfq");
+DEF_NATIVE(pv_irq_ops, save_fl, "pushfq; popq %rax");
+DEF_NATIVE(pv_cpu_ops, iret, "iretq");
+DEF_NATIVE(pv_mmu_ops, read_cr2, "movq %cr2, %rax");
+DEF_NATIVE(pv_mmu_ops, read_cr3, "movq %cr3, %rax");
+DEF_NATIVE(pv_mmu_ops, write_cr3, "movq %rdi, %cr3");
+DEF_NATIVE(pv_mmu_ops, flush_tlb_single, "invlpg (%rdi)");
+DEF_NATIVE(pv_cpu_ops, clts, "clts");
+DEF_NATIVE(pv_cpu_ops, wbinvd, "wbinvd");
+
+/* the three commands give us more control to how to return from a syscall */
+DEF_NATIVE(pv_cpu_ops, irq_enable_syscall_ret, "movq %gs:" __stringify(pda_oldrsp) ", %rsp; swapgs; sysretq;");
+DEF_NATIVE(pv_cpu_ops, swapgs, "swapgs");
+
+unsigned native_patch(u8 type, u16 clobbers, void *ibuf,
+ unsigned long addr, unsigned len)
+{
+ const unsigned char *start, *end;
+ unsigned ret;
+
+#define PATCH_SITE(ops, x) \
+ case PARAVIRT_PATCH(ops.x): \
+ start = start_##ops##_##x; \
+ end = end_##ops##_##x; \
+ goto patch_site
+ switch(type) {
+ PATCH_SITE(pv_irq_ops, restore_fl);
+ PATCH_SITE(pv_irq_ops, save_fl);
+ PATCH_SITE(pv_irq_ops, irq_enable);
+ PATCH_SITE(pv_irq_ops, irq_disable);
+ PATCH_SITE(pv_cpu_ops, iret);
+ PATCH_SITE(pv_cpu_ops, irq_enable_syscall_ret);
+ PATCH_SITE(pv_cpu_ops, swapgs);
+ PATCH_SITE(pv_mmu_ops, read_cr2);
+ PATCH_SITE(pv_mmu_ops, read_cr3);
+ PATCH_SITE(pv_mmu_ops, write_cr3);
+ PATCH_SITE(pv_cpu_ops, clts);
+ PATCH_SITE(pv_mmu_ops, flush_tlb_single);
+ PATCH_SITE(pv_cpu_ops, wbinvd);
+
+ patch_site:
+ ret = paravirt_patch_insns(ibuf, len, start, end);
+ break;
+
+ default:
+ ret = paravirt_patch_default(type, clobbers, ibuf, addr, len);
+ break;
+ }
+#undef PATCH_SITE
+ return ret;
+}