From: Rusty Russell <rusty@rustcorp.com.au>
To: lkml - Kernel Mailing List <linux-kernel@vger.kernel.org>
Cc: Zachary Amsden <zach@vmware.com>,
Jeremy Fitzhardinge <jeremy@xensource.com>,
Ingo Molnar <mingo@elte.hu>,
Andrew Morton <akpm@linux-foundation.org>,
Andi Kleen <ak@suse.de>
Subject: [PATCH 7/8] Page-align the GDT
Date: Wed, 07 Mar 2007 00:01:47 +1100 [thread overview]
Message-ID: <1173186107.4644.41.camel@localhost.localdomain> (raw)
In-Reply-To: <1173186021.4644.38.camel@localhost.localdomain>
Xen wants a dedicated page for the GDT. I believe VMI likes it too.
lguest, KVM and native don't care.
Simple transformation to page-aligned "struct gdt_page".
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
diff -r 576929b5b43f arch/i386/kernel/cpu/common.c
--- a/arch/i386/kernel/cpu/common.c Tue Mar 06 16:28:38 2007 +1100
+++ b/arch/i386/kernel/cpu/common.c Tue Mar 06 16:47:11 2007 +1100
@@ -22,8 +22,8 @@
#include "cpu.h"
-DEFINE_PER_CPU(struct desc_struct, cpu_gdt[GDT_ENTRIES]);
-EXPORT_PER_CPU_SYMBOL_GPL(cpu_gdt);
+DEFINE_PER_CPU(struct gdt_page, gdt_page);
+EXPORT_PER_CPU_SYMBOL_GPL(gdt_page);
DEFINE_PER_CPU(struct i386_pda, _cpu_pda);
EXPORT_PER_CPU_SYMBOL(_cpu_pda);
@@ -628,7 +628,7 @@ static inline void set_kernel_fs(void)
will soon come up. */
__cpuinit void init_gdt(int cpu, struct task_struct *idle)
{
- struct desc_struct *gdt = per_cpu(cpu_gdt, cpu);
+ struct desc_struct *gdt = per_cpu(gdt_page, cpu).gdt;
struct i386_pda *pda = &per_cpu(_cpu_pda, cpu);
/* Based on boot_gdt_table: set PDA so it can be used immediately */
@@ -649,7 +649,7 @@ void __cpuinit cpu_set_gdt(int cpu)
{
struct Xgt_desc_struct gdt_descr;
- gdt_descr.address = (unsigned long)per_cpu(cpu_gdt, cpu);
+ gdt_descr.address = (unsigned long)per_cpu(gdt_page, cpu).gdt;
gdt_descr.size = GDT_SIZE - 1;
load_gdt(&gdt_descr);
diff -r 576929b5b43f arch/i386/kernel/entry.S
--- a/arch/i386/kernel/entry.S Tue Mar 06 16:28:38 2007 +1100
+++ b/arch/i386/kernel/entry.S Tue Mar 06 16:47:11 2007 +1100
@@ -561,7 +561,7 @@ END(syscall_badsys)
#define FIXUP_ESPFIX_STACK \
/* since we are on a wrong stack, we cant make it a C code :( */ \
movl %fs:PDA_cpu, %ebx; \
- PER_CPU(cpu_gdt, %ebx); \
+ PER_CPU(gdt_page, %ebx); \
GET_DESC_BASE(GDT_ENTRY_ESPFIX_SS, %ebx, %eax, %ax, %al, %ah); \
addl %esp, %eax; \
pushl $__KERNEL_DS; \
diff -r 576929b5b43f arch/i386/kernel/head.S
--- a/arch/i386/kernel/head.S Tue Mar 06 16:28:38 2007 +1100
+++ b/arch/i386/kernel/head.S Tue Mar 06 16:47:11 2007 +1100
@@ -592,7 +592,7 @@ ENTRY(early_gdt_descr)
.long boot_gdt_table
/* The boot Global Descriptor Table: after boot we allocate a per-cpu copy */
- .align L1_CACHE_BYTES
+ .p2align PAGE_SHIFT
ENTRY(boot_gdt_table)
.quad 0x0000000000000000 /* NULL descriptor */
.quad 0x0000000000000000 /* 0x0b reserved */
diff -r 576929b5b43f arch/i386/kernel/traps.c
--- a/arch/i386/kernel/traps.c Tue Mar 06 16:28:38 2007 +1100
+++ b/arch/i386/kernel/traps.c Tue Mar 06 16:28:40 2007 +1100
@@ -1018,7 +1018,7 @@ fastcall unsigned long patch_espfix_desc
fastcall unsigned long patch_espfix_desc(unsigned long uesp,
unsigned long kesp)
{
- struct desc_struct *gdt = __get_cpu_var(cpu_gdt);
+ struct desc_struct *gdt = __get_cpu_var(gdt_page).gdt;
unsigned long base = (kesp - uesp) & -THREAD_SIZE;
unsigned long new_kesp = kesp - base;
unsigned long lim_pages = (new_kesp | (THREAD_SIZE - 1)) >> PAGE_SHIFT;
diff -r 576929b5b43f include/asm-i386/desc.h
--- a/include/asm-i386/desc.h Tue Mar 06 16:28:38 2007 +1100
+++ b/include/asm-i386/desc.h Tue Mar 06 16:47:22 2007 +1100
@@ -13,7 +13,11 @@
#include <asm/mmu.h>
extern struct desc_struct boot_gdt_table[GDT_ENTRIES];
-DECLARE_PER_CPU(struct desc_struct, cpu_gdt[GDT_ENTRIES]);
+struct gdt_page
+{
+ struct desc_struct gdt[GDT_ENTRIES];
+} __attribute__((aligned(PAGE_SIZE)));
+DECLARE_PER_CPU(struct gdt_page, gdt_page);
struct Xgt_desc_struct {
unsigned short size;
@@ -24,7 +28,7 @@ extern struct Xgt_desc_struct idt_descr;
extern struct Xgt_desc_struct idt_descr;
static inline struct desc_struct *get_cpu_gdt_table(unsigned int cpu)
{
- return per_cpu(cpu_gdt, cpu);
+ return per_cpu(gdt_page, cpu).gdt;
}
extern struct desc_struct idt_table[];
@@ -104,7 +108,8 @@ static inline fastcall void native_set_l
pack_descriptor(&a, &b, (unsigned long)addr,
entries * sizeof(struct desc_struct) - 1,
DESCTYPE_LDT, 0);
- write_gdt_entry(__get_cpu_var(cpu_gdt), GDT_ENTRY_LDT, a, b);
+ write_gdt_entry(__get_cpu_var(gdt_page).gdt, GDT_ENTRY_LDT,
+ a, b);
__asm__ __volatile__("lldt %w0"::"q" (GDT_ENTRY_LDT*8));
}
}
next prev parent reply other threads:[~2007-03-06 13:02 UTC|newest]
Thread overview: 36+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-03-06 12:39 [PATCH 0/8] x86 boot, pda and gdt cleanups Rusty Russell
2007-03-06 12:53 ` [PATCH 1/8] Remove cpu_gdt_table: use boot_gdt_table until migration to per-cpu Rusty Russell
2007-03-06 12:54 ` [PATCH 2/8] Remove NR_CPUS from asm-generic/percpu.h Rusty Russell
2007-03-06 12:55 ` [PATCH 3/8] Use per-cpu variables for GDT, PDA Rusty Russell
2007-03-06 12:57 ` [PATCH 4/8] Cleanup setup_pda Rusty Russell
2007-03-06 12:58 ` [PATCH 5/8] Cleanup GDT access Rusty Russell
2007-03-06 13:00 ` [PATCH 6/8] Allow per-cpu variables to be page-aligned Rusty Russell
2007-03-06 13:01 ` Rusty Russell [this message]
2007-03-06 13:03 ` [PATCH 8/8] Convert PDA into the percpu section Rusty Russell
2007-03-06 13:10 ` Ingo Molnar
2007-03-07 0:12 ` Rusty Russell
2007-03-07 0:35 ` Jeremy Fitzhardinge
2007-03-06 18:28 ` Jeremy Fitzhardinge
2007-03-06 19:34 ` Andi Kleen
2007-03-06 18:37 ` Jeremy Fitzhardinge
2007-03-07 0:33 ` Rusty Russell
2007-03-07 11:55 ` Rusty Russell
2007-03-13 17:15 ` Jeremy Fitzhardinge
2007-03-14 2:27 ` Rusty Russell
2007-03-06 13:15 ` [PATCH 6/8] Allow per-cpu variables to be page-aligned Ingo Molnar
2007-03-07 0:16 ` Rusty Russell
2007-03-07 0:44 ` H. Peter Anvin
2007-03-06 18:17 ` Jeremy Fitzhardinge
2007-03-07 0:29 ` Rusty Russell
2007-03-06 18:16 ` [PATCH 5/8] Cleanup GDT access Jeremy Fitzhardinge
2007-03-06 18:14 ` [PATCH 3/8] Use per-cpu variables for GDT, PDA Jeremy Fitzhardinge
2007-03-06 13:21 ` [PATCH 2/8] Remove NR_CPUS from asm-generic/percpu.h Ingo Molnar
2007-03-06 13:20 ` [PATCH 1/8] Remove cpu_gdt_table: use boot_gdt_table until migration to per-cpu Ingo Molnar
2007-03-06 13:26 ` Ingo Molnar
2007-03-07 0:22 ` Rusty Russell
2007-03-13 20:48 ` [PATCH 0/8] x86 boot, pda and gdt cleanups Jeremy Fitzhardinge
2007-03-14 2:25 ` Rusty Russell
2007-03-14 4:39 ` Jeremy Fitzhardinge
2007-03-14 6:54 ` Rusty Russell
2007-03-14 23:55 ` Rusty Russell
2007-03-15 1:57 ` Jeremy Fitzhardinge
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