x86: add %gs accessors for x86_32

Impact: cleanup

On x86_32, %gs is handled lazily.  It's not saved and restored on
kernel entry/exit but only when necessary which usually is during task
switch but there are few other places.  Currently, it's done by
calling savesegment() and loadsegment() explicitly.  Define
get_user_gs(), set_user_gs() and task_user_gs() and use them instead.

While at it, clean up register access macros in signal.c.

This cleans up code a bit and will help future changes.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 1 insertions, 1 deletions

diff --git a/arch/x86/include/asm/elf.h b/arch/x86/include/asm/elf.h
index f51a3ddde01a..39b0aac1675c 100644
--- a/arch/x86/include/asm/elf.h
+++ b/arch/x86/include/asm/elf.h
@@ -124,7 +124,7 @@ do {						\
         pr_reg[7] = regs->ds & 0xffff;          \
         pr_reg[8] = regs->es & 0xffff;          \
         pr_reg[9] = regs->fs & 0xffff;          \
-        savesegment(gs, pr_reg[10]);            \
+        pr_reg[10] = get_user_gs(regs);         \
         pr_reg[11] = regs->orig_ax;             \
         pr_reg[12] = regs->ip;                  \
         pr_reg[13] = regs->cs & 0xffff;         \