#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>
/* Per processor datastructure. %gs points to it while the kernel runs */
struct x8664_pda {
struct task_struct *pcurrent; /* 0 Current process */
unsigned long data_offset; /* 8 Per cpu data offset from linker
address */
unsigned long kernelstack; /* 16 top of kernel stack for current */
unsigned long oldrsp; /* 24 user rsp for system call */
int irqcount; /* 32 Irq nesting counter. Starts with -1 */
int cpunumber; /* 36 Logical CPU number */
#ifdef CONFIG_CC_STACKPROTECTOR
unsigned long stack_canary; /* 40 stack canary value */
/* gcc-ABI: this canary MUST be at
offset 40!!! */
#endif
char *irqstackptr;
int nodenumber; /* number of current node */
unsigned int __softirq_pending;
unsigned int __nmi_count; /* number of NMI on this CPUs */
short mmu_state;
short isidle;
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.
*/
extern void __bad_pda_field(void) __attribute__((noreturn));
/*
* proxy_pda doesn't actually exist, but tell gcc it is accessed for
* all PDA accesses so it gets read/write dependencies right.
*/
extern struct x8664_pda _proxy_pda;
#define pda_offset(field) offsetof(struct x8664_pda, field)
#define pda_to_op(op,field,val) do { \
typedef typeof(_proxy_pda.field) T__; \
if (0) { T__ tmp__; tmp__ = (val); } /* type checking */ \
switch (sizeof(_proxy_pda.field)) { \
case 2: \
asm(op "w %1,%%gs:%c2" : \
"+m" (_proxy_pda.field) : \
"ri" ((T__)val), \
"i"(pda_offset(field))); \
break; \
case 4: \
asm(op "l %1,%%gs:%c2" : \
"+m" (_proxy_pda.field) : \
"ri" ((T__)val), \
"i" (pda_offset(field))); \
break; \
case 8: \
asm(op "q %1,%%gs:%c2": \
"+m" (_proxy_pda.field) : \
"ri" ((T__)val), \
"i"(pda_offset(field))); \
break; \
default: \
__bad_pda_field(); \
} \
} while (0)
#define pda_from_op(op,field) ({ \
typeof(_proxy_pda.field) ret__; \
switch (sizeof(_proxy_pda.field)) { \
case 2: \
asm(op "w %%gs:%c1,%0" : \
"=r" (ret__) : \
"i" (pda_offset(field)), \
"m" (_proxy_pda.field)); \
break; \
case 4: \
asm(op "l %%gs:%c1,%0": \
"=r" (ret__): \
"i" (pda_offset(field)), \
"m" (_proxy_pda.field)); \
break; \
case 8: \
asm(op "q %%gs:%c1,%0": \
"=r" (ret__) : \
"i" (pda_offset(field)), \
"m" (_proxy_pda.field)); \
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)
/* This is not atomic against other CPUs -- CPU preemption needs to be off */
#define test_and_clear_bit_pda(bit,field) ({ \
int old__; \
asm volatile("btr %2,%%gs:%c3\n\tsbbl %0,%0" \
: "=r" (old__), "+m" (_proxy_pda.field) \
: "dIr" (bit), "i" (pda_offset(field)) : "memory"); \
old__; \
})
#endif
#define PDA_STACKOFFSET (5*8)
#endif
