Move lguest hcalls to arch-specific header

Move architecture specific portion of lg_hcall code to asm-i386/lg_hcall.h
and have it included from linux/lguest.h.

[Changed to asm-i386/lguest_hcall.h so documentation finds it -RR]

Signed-off-by: Jes Sorensen <jes@sgi.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Jes Sorensen <jes@sgi.com>

1 files changed, 67 insertions, 0 deletions

diff --git a/include/asm-x86/lguest_hcall.h b/include/asm-x86/lguest_hcall.h
new file mode 100644
index 000000000000..7859cfe0ebb2
--- /dev/null
+++ b/include/asm-x86/lguest_hcall.h
@@ -0,0 +1,67 @@
+/* Architecture specific portion of the lguest hypercalls */
+#ifndef _X86_LGUEST_HCALL_H
+#define _X86_LGUEST_HCALL_H
+
+#define LHCALL_FLUSH_ASYNC      0
+#define LHCALL_LGUEST_INIT      1
+#define LHCALL_CRASH            2
+#define LHCALL_LOAD_GDT         3
+#define LHCALL_NEW_PGTABLE      4
+#define LHCALL_FLUSH_TLB        5
+#define LHCALL_LOAD_IDT_ENTRY   6
+#define LHCALL_SET_STACK        7
+#define LHCALL_TS               8
+#define LHCALL_SET_CLOCKEVENT   9
+#define LHCALL_HALT             10
+#define LHCALL_BIND_DMA         12
+#define LHCALL_SEND_DMA         13
+#define LHCALL_SET_PTE          14
+#define LHCALL_SET_PMD          15
+#define LHCALL_LOAD_TLS         16
+
+/*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
+ * 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.
+ *
+ * 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
+
+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 */
+                     : "=a"(call)
+                       /* The other 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
+                        * gcc that it might happen so it doesn't get clever. */
+                     : "memory");
+        return call;
+}
+/*:*/
+
+void async_hcall(unsigned long call,
+                 unsigned long arg1, unsigned long arg2, unsigned long arg3);
+
+/* Can't use our min() macro here: needs to be a constant */
+#define LGUEST_IRQS (NR_IRQS < 32 ? NR_IRQS: 32)
+
+#define LHCALL_RING_SIZE 64
+struct hcall_ring
+{
+        u32 eax, edx, ebx, ecx;
+};
+
+#endif  /* _I386_LGUEST_HCALL_H */