#ifndef X86_64_PDA_H

#define X86_64_PDA_H

#ifndef __ASSEMBLY__

#include <linux/stddef.h>

#include <linux/types.h>

#include <linux/cache.h>

#include <asm/page.h>

#if !defined(__VMKLNX__)

/* Per processor datastructure. %gs points to it while the kernel runs */ 

struct x8664_pda {

	struct task_struct *pcurrent;	/* Current process */

	unsigned long data_offset;	/* Per cpu data offset from linker address */

	unsigned long kernelstack;  /* top of kernel stack for current */ 

	unsigned long oldrsp; 	    /* user rsp for system call */

#if DEBUG_STKSZ > EXCEPTION_STKSZ

	unsigned long debugstack;   /* #DB/#BP stack. */

#endif

        int irqcount;		    /* Irq nesting counter. Starts with -1 */  	

	int cpunumber;		    /* Logical CPU number */

	char *irqstackptr;	/* top of irqstack */

	int nodenumber;		    /* number of current node */

	unsigned int __softirq_pending;

	unsigned int __nmi_count;	/* number of NMI on this CPUs */

	int mmu_state;     

	struct mm_struct *active_mm;

	unsigned apic_timer_irqs;

} ____cacheline_aligned_in_smp;

extern struct x8664_pda *_cpu_pda[];

extern struct x8664_pda boot_cpu_pda[];

#define cpu_pda(i) (_cpu_pda[i])

/* 

 * There is no fast way to get the base address of the PDA, all the accesses

 * have to mention %fs/%gs.  So it needs to be done this Torvaldian way.

 */ 

#define sizeof_field(type,field)  (sizeof(((type *)0)->field))

#define typeof_field(type,field)  typeof(((type *)0)->field)

extern void __bad_pda_field(void);

#define pda_offset(field) offsetof(struct x8664_pda, field)

#define pda_to_op(op,field,val) do { \

	typedef typeof_field(struct x8664_pda, field) T__; \

       switch (sizeof_field(struct x8664_pda, field)) { 		\

case 2: \

asm volatile(op "w %0,%%gs:%P1"::"ri" ((T__)val),"i"(pda_offset(field)):"memory"); break; \

case 4: \

asm volatile(op "l %0,%%gs:%P1"::"ri" ((T__)val),"i"(pda_offset(field)):"memory"); break; \

case 8: \

asm volatile(op "q %0,%%gs:%P1"::"ri" ((T__)val),"i"(pda_offset(field)):"memory"); break; \

       default: __bad_pda_field(); 					\

       } \

       } while (0)

/* 

 * AK: PDA read accesses should be neither volatile nor have an memory clobber.

 * Unfortunately removing them causes all hell to break lose currently.

 */

#define pda_from_op(op,field) ({ \

       typeof_field(struct x8664_pda, field) ret__; \

       switch (sizeof_field(struct x8664_pda, field)) { 		\

case 2: \

asm volatile(op "w %%gs:%P1,%0":"=r" (ret__):"i"(pda_offset(field)):"memory"); break;\

case 4: \

asm volatile(op "l %%gs:%P1,%0":"=r" (ret__):"i"(pda_offset(field)):"memory"); break;\

case 8: \

asm volatile(op "q %%gs:%P1,%0":"=r" (ret__):"i"(pda_offset(field)):"memory"); break;\

       default: __bad_pda_field(); 					\

       } \

       ret__; })

#define read_pda(field) pda_from_op("mov",field)

#define write_pda(field,val) pda_to_op("mov",field,val)

#define add_pda(field,val) pda_to_op("add",field,val)

#define sub_pda(field,val) pda_to_op("sub",field,val)

#define or_pda(field,val) pda_to_op("or",field,val)

#endif

#define PDA_STACKOFFSET (5*8)

#endif /* !defined(__VMKLNX__) */

#endif