Gitweb:     
http://git.kernel.org/git/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=f87ea91d988637b3bbf6aa2d281c6010e7d5f48d
Commit:     f87ea91d988637b3bbf6aa2d281c6010e7d5f48d
Parent:     966f1d8f344bcec3db7d774a4ba3ab0dedfad873
Author:     Jeff Dike <[EMAIL PROTECTED]>
AuthorDate: Mon Feb 4 22:31:29 2008 -0800
Committer:  Linus Torvalds <[EMAIL PROTECTED]>
CommitDate: Tue Feb 5 09:44:32 2008 -0800

    uml: redo the calculation of NR_syscalls
    
    Redo the calculation of NR_syscalls since that disappeared from i386 and
    use a similar mechanism on x86_64.
    
    We now figure out the size of the system call table in arch code and stick
    that in syscall_table_size.  arch/um/kernel/skas/syscall.c defines
    NR_syscalls in terms of that since its the only thing that needs to know
    how many system calls there are.
    
    The old mechananism that was used on x86_64 is gone.
    
    arch/um/include/sysdep-i386/syscalls.h got some formatting since I was
    looking at it.
    
    Signed-off-by: Jeff Dike <[EMAIL PROTECTED]>
    Cc: WANG Cong <[EMAIL PROTECTED]>
    Signed-off-by: Andrew Morton <[EMAIL PROTECTED]>
    Signed-off-by: Linus Torvalds <[EMAIL PROTECTED]>
---
 arch/um/include/sysdep-i386/syscalls.h         |    5 +++--
 arch/um/include/sysdep-x86_64/kernel-offsets.h |    9 ---------
 arch/um/include/sysdep-x86_64/syscalls.h       |    2 --
 arch/um/kernel/skas/syscall.c                  |    3 +++
 arch/um/sys-i386/sys_call_table.S              |    5 +++++
 arch/um/sys-x86_64/syscall_table.c             |   20 ++++++++++++++------
 6 files changed, 25 insertions(+), 19 deletions(-)

diff --git a/arch/um/include/sysdep-i386/syscalls.h 
b/arch/um/include/sysdep-i386/syscalls.h
index 57bd79e..9056981 100644
--- a/arch/um/include/sysdep-i386/syscalls.h
+++ b/arch/um/include/sysdep-i386/syscalls.h
@@ -1,5 +1,5 @@
 /* 
- * Copyright (C) 2000 Jeff Dike ([EMAIL PROTECTED])
+ * Copyright (C) 2000 - 2008 Jeff Dike ([EMAIL PROTECTED],linux.intel}.com)
  * Licensed under the GPL
  */
 
@@ -18,7 +18,8 @@ extern syscall_handler_t old_mmap_i386;
 extern syscall_handler_t *sys_call_table[];
 
 #define EXECUTE_SYSCALL(syscall, regs) \
-       ((long (*)(struct syscall_args)) 
(*sys_call_table[syscall]))(SYSCALL_ARGS(&regs->regs))
+       ((long (*)(struct syscall_args)) \
+        (*sys_call_table[syscall]))(SYSCALL_ARGS(&regs->regs))
 
 extern long sys_mmap2(unsigned long addr, unsigned long len,
                      unsigned long prot, unsigned long flags,
diff --git a/arch/um/include/sysdep-x86_64/kernel-offsets.h 
b/arch/um/include/sysdep-x86_64/kernel-offsets.h
index c978b58..a307237 100644
--- a/arch/um/include/sysdep-x86_64/kernel-offsets.h
+++ b/arch/um/include/sysdep-x86_64/kernel-offsets.h
@@ -17,16 +17,7 @@
 #define OFFSET(sym, str, mem) \
        DEFINE(sym, offsetof(struct str, mem));
 
-#define __NO_STUBS 1
-#undef __SYSCALL
-#undef _ASM_X86_64_UNISTD_H_
-#define __SYSCALL(nr, sym) [nr] = 1,
-static char syscalls[] = {
-#include <asm/arch/unistd.h>
-};
-
 void foo(void)
 {
 #include <common-offsets.h>
-DEFINE(UM_NR_syscall_max, sizeof(syscalls) - 1);
 }
diff --git a/arch/um/include/sysdep-x86_64/syscalls.h 
b/arch/um/include/sysdep-x86_64/syscalls.h
index cf72256..7cfb0b0 100644
--- a/arch/um/include/sysdep-x86_64/syscalls.h
+++ b/arch/um/include/sysdep-x86_64/syscalls.h
@@ -30,6 +30,4 @@ extern long old_mmap(unsigned long addr, unsigned long len,
 extern syscall_handler_t sys_modify_ldt;
 extern syscall_handler_t sys_arch_prctl;
 
-#define NR_syscalls (UM_NR_syscall_max + 1)
-
 #endif
diff --git a/arch/um/kernel/skas/syscall.c b/arch/um/kernel/skas/syscall.c
index 6450f02..4e3b820 100644
--- a/arch/um/kernel/skas/syscall.c
+++ b/arch/um/kernel/skas/syscall.c
@@ -9,6 +9,9 @@
 #include "sysdep/ptrace.h"
 #include "sysdep/syscalls.h"
 
+extern int syscall_table_size;
+#define NR_syscalls (syscall_table_size / sizeof(void *))
+
 void handle_syscall(struct uml_pt_regs *r)
 {
        struct pt_regs *regs = container_of(r, struct pt_regs, regs);
diff --git a/arch/um/sys-i386/sys_call_table.S 
b/arch/um/sys-i386/sys_call_table.S
index 12d4148..00e5f52 100644
--- a/arch/um/sys-i386/sys_call_table.S
+++ b/arch/um/sys-i386/sys_call_table.S
@@ -9,4 +9,9 @@
 
 #define old_mmap old_mmap_i386
 
+.section .rodata,"a"
+
 #include "../../x86/kernel/syscall_table_32.S"
+
+ENTRY(syscall_table_size)
+.long .-sys_call_table
diff --git a/arch/um/sys-x86_64/syscall_table.c 
b/arch/um/sys-x86_64/syscall_table.c
index 555faee..c128eb8 100644
--- a/arch/um/sys-x86_64/syscall_table.c
+++ b/arch/um/sys-x86_64/syscall_table.c
@@ -52,11 +52,19 @@ typedef void (*sys_call_ptr_t)(void);
 
 extern void sys_ni_syscall(void);
 
-sys_call_ptr_t sys_call_table[UM_NR_syscall_max+1] __cacheline_aligned = {
-       /*
-        * Smells like a like a compiler bug -- it doesn't work when the &
-        * below is removed.
-        */
-       [0 ... UM_NR_syscall_max] = &sys_ni_syscall,
+/*
+ * We used to have a trick here which made sure that holes in the
+ * x86_64 table were filled in with sys_ni_syscall, but a comment in
+ * unistd_64.h says that holes aren't allowed, so the trick was
+ * removed.
+ * The trick looked like this
+ *     [0 ... UM_NR_syscall_max] = &sys_ni_syscall
+ * before including unistd_64.h - the later initializations overwrote
+ * the sys_ni_syscall filler.
+ */
+
+sys_call_ptr_t sys_call_table[] __cacheline_aligned = {
 #include <asm-x86/unistd_64.h>
 };
+
+int syscall_table_size = sizeof(sys_call_table);
-
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