[PATCH] Make vm86 support optional

This adds an option to remove vm86 support under CONFIG_EMBEDDED.  Saves
about 5k.

This version eliminates most of the #ifdefs of the previous version and
instead uses function stubs in vm86.h.  Also, release_vm86_irqs is moved
from asm-i386/irq.h to a more appropriate home in vm86.h so that the stubs
can live together.

$ size vmlinux-baseline vmlinux-novm86
   text    data     bss     dec     hex filename
2920821  523232  190652 3634705  377611 vmlinux-baseline
2916268  523100  190492 3629860  376324 vmlinux-novm86

Signed-off-by: Matt Mackall <mpm@selenic.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

2 files changed, 20 insertions, 2 deletions

diff --git a/include/asm-i386/irq.h b/include/asm-i386/irq.h
index 270f1986b19f..5169d7af456f 100644
--- a/include/asm-i386/irq.h
+++ b/include/asm-i386/irq.h
@@ -21,8 +21,6 @@ static __inline__ int irq_canonicalize(int irq)
         return ((irq == 2) ? 9 : irq);
 }
 
-extern void release_vm86_irqs(struct task_struct *);
-
 #ifdef CONFIG_X86_LOCAL_APIC
 # define ARCH_HAS_NMI_WATCHDOG          /* See include/linux/nmi.h */
 #endif
diff --git a/include/asm-i386/vm86.h b/include/asm-i386/vm86.h
index 40ec82c6914d..952fd6957380 100644
--- a/include/asm-i386/vm86.h
+++ b/include/asm-i386/vm86.h
@@ -16,7 +16,11 @@
 #define IF_MASK         0x00000200
 #define IOPL_MASK       0x00003000
 #define NT_MASK         0x00004000
+#ifdef CONFIG_VM86
 #define VM_MASK         0x00020000
+#else
+#define VM_MASK         0 /* ignored */
+#endif
 #define AC_MASK         0x00040000
 #define VIF_MASK        0x00080000      /* virtual interrupt flag */
 #define VIP_MASK        0x00100000      /* virtual interrupt pending */
@@ -200,9 +204,25 @@ struct kernel_vm86_struct {
  */
 };
 
+#ifdef CONFIG_VM86
+
 void handle_vm86_fault(struct kernel_vm86_regs *, long);
 int handle_vm86_trap(struct kernel_vm86_regs *, long, int);
 
+struct task_struct;
+void release_vm86_irqs(struct task_struct *);
+
+#else
+
+#define handle_vm86_fault(a, b)
+#define release_vm86_irqs(a)
+
+static inline int handle_vm86_trap(struct kernel_vm86_regs *a, long b, int c) {
+        return 0;
+}
+
+#endif /* CONFIG_VM86 */
+
 #endif /* __KERNEL__ */
 
 #endif