linux_dsm_epyc7002/arch/x86/include/asm/cpu_entry_area.h
Ingo Molnar 186525bd6b mm, x86/mm: Untangle address space layout definitions from basic pgtable type definitions
- Untangle the somewhat incestous way of how VMALLOC_START is used all across the
  kernel, but is, on x86, defined deep inside one of the lowest level page table headers.
  It doesn't help that vmalloc.h only includes a single asm header:

     #include <asm/page.h>           /* pgprot_t */

  So there was no existing cross-arch way to decouple address layout
  definitions from page.h details. I used this:

   #ifndef VMALLOC_START
   # include <asm/vmalloc.h>
   #endif

  This way every architecture that wants to simplify page.h can do so.

- Also on x86 we had a couple of LDT related inline functions that used
  the late-stage address space layout positions - but these could be
  uninlined without real trouble - the end result is cleaner this way as
  well.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: linux-kernel@vger.kernel.org
Cc: linux-mm@kvack.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-12-10 10:12:55 +01:00

149 lines
4.0 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_X86_CPU_ENTRY_AREA_H
#define _ASM_X86_CPU_ENTRY_AREA_H
#include <linux/percpu-defs.h>
#include <asm/processor.h>
#include <asm/intel_ds.h>
#include <asm/pgtable_areas.h>
#ifdef CONFIG_X86_64
/* Macro to enforce the same ordering and stack sizes */
#define ESTACKS_MEMBERS(guardsize, db2_holesize)\
char DF_stack_guard[guardsize]; \
char DF_stack[EXCEPTION_STKSZ]; \
char NMI_stack_guard[guardsize]; \
char NMI_stack[EXCEPTION_STKSZ]; \
char DB2_stack_guard[guardsize]; \
char DB2_stack[db2_holesize]; \
char DB1_stack_guard[guardsize]; \
char DB1_stack[EXCEPTION_STKSZ]; \
char DB_stack_guard[guardsize]; \
char DB_stack[EXCEPTION_STKSZ]; \
char MCE_stack_guard[guardsize]; \
char MCE_stack[EXCEPTION_STKSZ]; \
char IST_top_guard[guardsize]; \
/* The exception stacks' physical storage. No guard pages required */
struct exception_stacks {
ESTACKS_MEMBERS(0, 0)
};
/* The effective cpu entry area mapping with guard pages. */
struct cea_exception_stacks {
ESTACKS_MEMBERS(PAGE_SIZE, EXCEPTION_STKSZ)
};
/*
* The exception stack ordering in [cea_]exception_stacks
*/
enum exception_stack_ordering {
ESTACK_DF,
ESTACK_NMI,
ESTACK_DB2,
ESTACK_DB1,
ESTACK_DB,
ESTACK_MCE,
N_EXCEPTION_STACKS
};
#define CEA_ESTACK_SIZE(st) \
sizeof(((struct cea_exception_stacks *)0)->st## _stack)
#define CEA_ESTACK_BOT(ceastp, st) \
((unsigned long)&(ceastp)->st## _stack)
#define CEA_ESTACK_TOP(ceastp, st) \
(CEA_ESTACK_BOT(ceastp, st) + CEA_ESTACK_SIZE(st))
#define CEA_ESTACK_OFFS(st) \
offsetof(struct cea_exception_stacks, st## _stack)
#define CEA_ESTACK_PAGES \
(sizeof(struct cea_exception_stacks) / PAGE_SIZE)
#endif
#ifdef CONFIG_X86_32
struct doublefault_stack {
unsigned long stack[(PAGE_SIZE - sizeof(struct x86_hw_tss)) / sizeof(unsigned long)];
struct x86_hw_tss tss;
} __aligned(PAGE_SIZE);
#endif
/*
* cpu_entry_area is a percpu region that contains things needed by the CPU
* and early entry/exit code. Real types aren't used for all fields here
* to avoid circular header dependencies.
*
* Every field is a virtual alias of some other allocated backing store.
* There is no direct allocation of a struct cpu_entry_area.
*/
struct cpu_entry_area {
char gdt[PAGE_SIZE];
/*
* The GDT is just below entry_stack and thus serves (on x86_64) as
* a read-only guard page. On 32-bit the GDT must be writeable, so
* it needs an extra guard page.
*/
#ifdef CONFIG_X86_32
char guard_entry_stack[PAGE_SIZE];
#endif
struct entry_stack_page entry_stack_page;
#ifdef CONFIG_X86_32
char guard_doublefault_stack[PAGE_SIZE];
struct doublefault_stack doublefault_stack;
#endif
/*
* On x86_64, the TSS is mapped RO. On x86_32, it's mapped RW because
* we need task switches to work, and task switches write to the TSS.
*/
struct tss_struct tss;
#ifdef CONFIG_X86_64
/*
* Exception stacks used for IST entries with guard pages.
*/
struct cea_exception_stacks estacks;
#endif
/*
* Per CPU debug store for Intel performance monitoring. Wastes a
* full page at the moment.
*/
struct debug_store cpu_debug_store;
/*
* The actual PEBS/BTS buffers must be mapped to user space
* Reserve enough fixmap PTEs.
*/
struct debug_store_buffers cpu_debug_buffers;
};
#define CPU_ENTRY_AREA_SIZE (sizeof(struct cpu_entry_area))
#define CPU_ENTRY_AREA_ARRAY_SIZE (CPU_ENTRY_AREA_SIZE * NR_CPUS)
/* Total size includes the readonly IDT mapping page as well: */
#define CPU_ENTRY_AREA_TOTAL_SIZE (CPU_ENTRY_AREA_ARRAY_SIZE + PAGE_SIZE)
DECLARE_PER_CPU(struct cpu_entry_area *, cpu_entry_area);
DECLARE_PER_CPU(struct cea_exception_stacks *, cea_exception_stacks);
extern void setup_cpu_entry_areas(void);
extern void cea_set_pte(void *cea_vaddr, phys_addr_t pa, pgprot_t flags);
extern struct cpu_entry_area *get_cpu_entry_area(int cpu);
static inline struct entry_stack *cpu_entry_stack(int cpu)
{
return &get_cpu_entry_area(cpu)->entry_stack_page.stack;
}
#define __this_cpu_ist_top_va(name) \
CEA_ESTACK_TOP(__this_cpu_read(cea_exception_stacks), name)
#endif