linux/arch/powerpc/include/asm/paca.h
Matt Evans fc53b4202e powerpc/kexec: Switch to a static PACA on the way out
With dynamic PACAs, the kexecing CPU's PACA won't lie within the kernel
static data and there is a chance that something may stomp it when preparing
to kexec.  This patch switches this final CPU to a static PACA just before
we pull the switch.

Signed-off-by: Matt Evans <matt@ozlabs.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-07-31 14:56:30 +10:00

162 lines
5.1 KiB
C

/*
* This control block defines the PACA which defines the processor
* specific data for each logical processor on the system.
* There are some pointers defined that are utilized by PLIC.
*
* C 2001 PPC 64 Team, IBM Corp
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#ifndef _ASM_POWERPC_PACA_H
#define _ASM_POWERPC_PACA_H
#ifdef __KERNEL__
#ifdef CONFIG_PPC64
#include <linux/init.h>
#include <asm/types.h>
#include <asm/lppaca.h>
#include <asm/mmu.h>
#include <asm/page.h>
#include <asm/exception-64e.h>
#ifdef CONFIG_KVM_BOOK3S_64_HANDLER
#include <asm/kvm_book3s_asm.h>
#endif
register struct paca_struct *local_paca asm("r13");
#if defined(CONFIG_DEBUG_PREEMPT) && defined(CONFIG_SMP)
extern unsigned int debug_smp_processor_id(void); /* from linux/smp.h */
/*
* Add standard checks that preemption cannot occur when using get_paca():
* otherwise the paca_struct it points to may be the wrong one just after.
*/
#define get_paca() ((void) debug_smp_processor_id(), local_paca)
#else
#define get_paca() local_paca
#endif
#define get_lppaca() (get_paca()->lppaca_ptr)
#define get_slb_shadow() (get_paca()->slb_shadow_ptr)
struct task_struct;
/*
* Defines the layout of the paca.
*
* This structure is not directly accessed by firmware or the service
* processor.
*/
struct paca_struct {
#ifdef CONFIG_PPC_BOOK3S
/*
* Because hw_cpu_id, unlike other paca fields, is accessed
* routinely from other CPUs (from the IRQ code), we stick to
* read-only (after boot) fields in the first cacheline to
* avoid cacheline bouncing.
*/
struct lppaca *lppaca_ptr; /* Pointer to LpPaca for PLIC */
#endif /* CONFIG_PPC_BOOK3S */
/*
* MAGIC: the spinlock functions in arch/powerpc/lib/locks.c
* load lock_token and paca_index with a single lwz
* instruction. They must travel together and be properly
* aligned.
*/
u16 lock_token; /* Constant 0x8000, used in locks */
u16 paca_index; /* Logical processor number */
u64 kernel_toc; /* Kernel TOC address */
u64 kernelbase; /* Base address of kernel */
u64 kernel_msr; /* MSR while running in kernel */
#ifdef CONFIG_PPC_STD_MMU_64
u64 stab_real; /* Absolute address of segment table */
u64 stab_addr; /* Virtual address of segment table */
#endif /* CONFIG_PPC_STD_MMU_64 */
void *emergency_sp; /* pointer to emergency stack */
u64 data_offset; /* per cpu data offset */
s16 hw_cpu_id; /* Physical processor number */
u8 cpu_start; /* At startup, processor spins until */
/* this becomes non-zero. */
u8 kexec_state; /* set when kexec down has irqs off */
#ifdef CONFIG_PPC_STD_MMU_64
struct slb_shadow *slb_shadow_ptr;
/*
* Now, starting in cacheline 2, the exception save areas
*/
/* used for most interrupts/exceptions */
u64 exgen[10] __attribute__((aligned(0x80)));
u64 exmc[10]; /* used for machine checks */
u64 exslb[10]; /* used for SLB/segment table misses
* on the linear mapping */
/* SLB related definitions */
u16 vmalloc_sllp;
u16 slb_cache_ptr;
u16 slb_cache[SLB_CACHE_ENTRIES];
#endif /* CONFIG_PPC_STD_MMU_64 */
#ifdef CONFIG_PPC_BOOK3E
pgd_t *pgd; /* Current PGD */
pgd_t *kernel_pgd; /* Kernel PGD */
u64 exgen[8] __attribute__((aligned(0x80)));
u64 extlb[EX_TLB_SIZE*3] __attribute__((aligned(0x80)));
u64 exmc[8]; /* used for machine checks */
u64 excrit[8]; /* used for crit interrupts */
u64 exdbg[8]; /* used for debug interrupts */
/* Kernel stack pointers for use by special exceptions */
void *mc_kstack;
void *crit_kstack;
void *dbg_kstack;
#endif /* CONFIG_PPC_BOOK3E */
mm_context_t context;
/*
* then miscellaneous read-write fields
*/
struct task_struct *__current; /* Pointer to current */
u64 kstack; /* Saved Kernel stack addr */
u64 stab_rr; /* stab/slb round-robin counter */
u64 saved_r1; /* r1 save for RTAS calls */
u64 saved_msr; /* MSR saved here by enter_rtas */
u16 trap_save; /* Used when bad stack is encountered */
u8 soft_enabled; /* irq soft-enable flag */
u8 hard_enabled; /* set if irqs are enabled in MSR */
u8 io_sync; /* writel() needs spin_unlock sync */
u8 perf_event_pending; /* PM interrupt while soft-disabled */
/* Stuff for accurate time accounting */
u64 user_time; /* accumulated usermode TB ticks */
u64 system_time; /* accumulated system TB ticks */
u64 startpurr; /* PURR/TB value snapshot */
u64 startspurr; /* SPURR value snapshot */
#ifdef CONFIG_KVM_BOOK3S_HANDLER
/* We use this to store guest state in */
struct kvmppc_book3s_shadow_vcpu shadow_vcpu;
#endif
};
extern struct paca_struct *paca;
extern __initdata struct paca_struct boot_paca;
extern void initialise_paca(struct paca_struct *new_paca, int cpu);
extern void setup_paca(struct paca_struct *new_paca);
extern void allocate_pacas(void);
extern void free_unused_pacas(void);
#else /* CONFIG_PPC64 */
static inline void allocate_pacas(void) { };
static inline void free_unused_pacas(void) { };
#endif /* CONFIG_PPC64 */
#endif /* __KERNEL__ */
#endif /* _ASM_POWERPC_PACA_H */