lguest: add operations to get/set a register from the Launcher.

[sfrench/cifs-2.6.git] / drivers / lguest / x86 / core.c

diff --git a/drivers/lguest/x86/core.c b/drivers/lguest/x86/core.c
index 922a1acbf652b9376e4b2dd39ba6be2859307594..f7a16b4ea456ec5f7a3c562944f23d3444c58d2e 100644 (file)
--- a/drivers/lguest/x86/core.c
+++ b/drivers/lguest/x86/core.c
@@ -181,6 +181,52 @@ static void run_guest_once(struct lg_cpu *cpu, struct lguest_pages *pages)
 }
 /*:*/
 
+unsigned long *lguest_arch_regptr(struct lg_cpu *cpu, size_t reg_off, bool any)
+{
+       switch (reg_off) {
+       case offsetof(struct pt_regs, bx):
+               return &cpu->regs->ebx;
+       case offsetof(struct pt_regs, cx):
+               return &cpu->regs->ecx;
+       case offsetof(struct pt_regs, dx):
+               return &cpu->regs->edx;
+       case offsetof(struct pt_regs, si):
+               return &cpu->regs->esi;
+       case offsetof(struct pt_regs, di):
+               return &cpu->regs->edi;
+       case offsetof(struct pt_regs, bp):
+               return &cpu->regs->ebp;
+       case offsetof(struct pt_regs, ax):
+               return &cpu->regs->eax;
+       case offsetof(struct pt_regs, ip):
+               return &cpu->regs->eip;
+       case offsetof(struct pt_regs, sp):
+               return &cpu->regs->esp;
+       }
+
+       /* Launcher can read these, but we don't allow any setting. */
+       if (any) {
+               switch (reg_off) {
+               case offsetof(struct pt_regs, ds):
+                       return &cpu->regs->ds;
+               case offsetof(struct pt_regs, es):
+                       return &cpu->regs->es;
+               case offsetof(struct pt_regs, fs):
+                       return &cpu->regs->fs;
+               case offsetof(struct pt_regs, gs):
+                       return &cpu->regs->gs;
+               case offsetof(struct pt_regs, cs):
+                       return &cpu->regs->cs;
+               case offsetof(struct pt_regs, flags):
+                       return &cpu->regs->eflags;
+               case offsetof(struct pt_regs, ss):
+                       return &cpu->regs->ss;
+               }
+       }
+
+       return NULL;
+}
+
 /*M:002
  * There are hooks in the scheduler which we can register to tell when we
  * get kicked off the CPU (preempt_notifier_register()).  This would allow us