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Diffstat (limited to 'include/asm-x86/lguest_hcall.h')
-rw-r--r--include/asm-x86/lguest_hcall.h16
1 files changed, 8 insertions, 8 deletions
diff --git a/include/asm-x86/lguest_hcall.h b/include/asm-x86/lguest_hcall.h
index f948491eb56..9c5092b6aa9 100644
--- a/include/asm-x86/lguest_hcall.h
+++ b/include/asm-x86/lguest_hcall.h
@@ -18,12 +18,17 @@
#define LHCALL_LOAD_TLS 16
#define LHCALL_NOTIFY 17
+#define LGUEST_TRAP_ENTRY 0x1F
+
+#ifndef __ASSEMBLY__
+#include <asm/hw_irq.h>
+
/*G:031 First, how does our Guest contact the Host to ask for privileged
* operations? There are two ways: the direct way is to make a "hypercall",
* to make requests of the Host Itself.
*
* Our hypercall mechanism uses the highest unused trap code (traps 32 and
- * above are used by real hardware interrupts). Seventeen hypercalls are
+ * above are used by real hardware interrupts). Fifteen hypercalls are
* available: the hypercall number is put in the %eax register, and the
* arguments (when required) are placed in %edx, %ebx and %ecx. If a return
* value makes sense, it's returned in %eax.
@@ -31,20 +36,15 @@
* Grossly invalid calls result in Sudden Death at the hands of the vengeful
* Host, rather than returning failure. This reflects Winston Churchill's
* definition of a gentleman: "someone who is only rude intentionally". */
-#define LGUEST_TRAP_ENTRY 0x1F
-
-#ifndef __ASSEMBLY__
-#include <asm/hw_irq.h>
-
static inline unsigned long
hcall(unsigned long call,
unsigned long arg1, unsigned long arg2, unsigned long arg3)
{
/* "int" is the Intel instruction to trigger a trap. */
asm volatile("int $" __stringify(LGUEST_TRAP_ENTRY)
- /* The call is in %eax (aka "a"), and can be replaced */
+ /* The call in %eax (aka "a") might be overwritten */
: "=a"(call)
- /* The other arguments are in %eax, %edx, %ebx & %ecx */
+ /* The arguments are in %eax, %edx, %ebx & %ecx */
: "a"(call), "d"(arg1), "b"(arg2), "c"(arg3)
/* "memory" means this might write somewhere in memory.
* This isn't true for all calls, but it's safe to tell