x86/pvops: add a paravirt_ident functions to allow special patching

[linux-block.git] / arch / x86 / kernel / paravirt_patch_64.c

diff --git a/arch/x86/kernel/paravirt_patch_64.c b/arch/x86/kernel/paravirt_patch_64.c
index 7d904e138d7e482cc9bb83e67db1b9718273a576..3f08f34f93ebc480041d0b448e3b12869450a91d 100644 (file)
--- a/arch/x86/kernel/paravirt_patch_64.c
+++ b/arch/x86/kernel/paravirt_patch_64.c
@@ -14,10 +14,26 @@ 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, irq_enable_sysexit, "swapgs; sti; sysexit");
+DEF_NATIVE(pv_cpu_ops, usergs_sysret64, "swapgs; sysretq");
+DEF_NATIVE(pv_cpu_ops, usergs_sysret32, "swapgs; sysretl");
 DEF_NATIVE(pv_cpu_ops, swapgs, "swapgs");
 
+DEF_NATIVE(, mov32, "mov %edi, %eax");
+DEF_NATIVE(, mov64, "mov %rdi, %rax");
+
+unsigned paravirt_patch_ident_32(void *insnbuf, unsigned len)
+{
+       return paravirt_patch_insns(insnbuf, len,
+                                   start__mov32, end__mov32);
+}
+
+unsigned paravirt_patch_ident_64(void *insnbuf, unsigned len)
+{
+       return paravirt_patch_insns(insnbuf, len,
+                                   start__mov64, end__mov64);
+}
+
 unsigned native_patch(u8 type, u16 clobbers, void *ibuf,
                      unsigned long addr, unsigned len)
 {
@@ -35,7 +51,9 @@ unsigned native_patch(u8 type, u16 clobbers, void *ibuf,
                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, irq_enable_sysexit);
+               PATCH_SITE(pv_cpu_ops, usergs_sysret32);
+               PATCH_SITE(pv_cpu_ops, usergs_sysret64);
                PATCH_SITE(pv_cpu_ops, swapgs);
                PATCH_SITE(pv_mmu_ops, read_cr2);
                PATCH_SITE(pv_mmu_ops, read_cr3);