ubuntu-linux-kernel/arch/x86/include/asm/cpu_entry_area.h

82 lines
2.3 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>
/*
* 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 a read-only guard page.
*/
struct entry_stack_page entry_stack_page;
/*
* 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;
char entry_trampoline[PAGE_SIZE];
#ifdef CONFIG_X86_64
/*
* Exception stacks used for IST entries.
*
* In the future, this should have a separate slot for each stack
* with guard pages between them.
*/
char exception_stacks[(N_EXCEPTION_STACKS - 1) * EXCEPTION_STKSZ + DEBUG_STKSZ];
#endif
#ifdef CONFIG_CPU_SUP_INTEL
/*
* 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;
#endif
};
#define CPU_ENTRY_AREA_SIZE (sizeof(struct cpu_entry_area))
#define CPU_ENTRY_AREA_TOT_SIZE (CPU_ENTRY_AREA_SIZE * NR_CPUS)
DECLARE_PER_CPU(struct cpu_entry_area *, cpu_entry_area);
extern void setup_cpu_entry_areas(void);
extern void cea_set_pte(void *cea_vaddr, phys_addr_t pa, pgprot_t flags);
#define CPU_ENTRY_AREA_RO_IDT CPU_ENTRY_AREA_BASE
#define CPU_ENTRY_AREA_PER_CPU (CPU_ENTRY_AREA_RO_IDT + PAGE_SIZE)
#define CPU_ENTRY_AREA_RO_IDT_VADDR ((void *)CPU_ENTRY_AREA_RO_IDT)
#define CPU_ENTRY_AREA_MAP_SIZE \
(CPU_ENTRY_AREA_PER_CPU + CPU_ENTRY_AREA_TOT_SIZE - CPU_ENTRY_AREA_BASE)
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;
}
#endif