[linux-2.6-block.git] / include / asm-x86_64 / pda.h

#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
Commit	Line	Data
1da177e4 LT	1	#ifndef X86_64_PDA_H
	2	#define X86_64_PDA_H
	3
	4	#ifndef __ASSEMBLY__
	5	#include <linux/stddef.h>
	6	#include <linux/types.h>
	7	#include <linux/cache.h>
b556b35e	8	#include <asm/page.h>
1da177e4 LT	9
	10	/* Per processor datastructure. %gs points to it while the kernel runs */
	11	struct x8664_pda {
29a9af60 AV	12	struct task_struct pcurrent; / 0 Current process */
	13	unsigned long data_offset; /* 8 Per cpu data offset from linker
	14	address */
	15	unsigned long kernelstack; /* 16 top of kernel stack for current */
	16	unsigned long oldrsp; /* 24 user rsp for system call */
	17	int irqcount; /* 32 Irq nesting counter. Starts with -1 */
	18	int cpunumber; /* 36 Logical CPU number */
0a425405 AV	19	#ifdef CONFIG_CC_STACKPROTECTOR
	20	unsigned long stack_canary; /* 40 stack canary value */
	21	/* gcc-ABI: this canary MUST be at
	22	offset 40!!! */
	23	#endif
	24	char *irqstackptr;
69d81fcd	25	int nodenumber; /* number of current node */
1da177e4 LT	26	unsigned int __softirq_pending;
1da177e4 LT	27	unsigned int __nmi_count; /* number of NMI on this CPUs */
a15da49d AK	28	short mmu_state;
a15da49d AK	29	short isidle;
df92004c	30	struct mm_struct *active_mm;
1da177e4	31	unsigned apic_timer_irqs;
b9169116	32	} ____cacheline_aligned_in_smp;
1da177e4	33
365ba917 RT	34	extern struct x8664_pda *_cpu_pda[];
365ba917 RT	35	extern struct x8664_pda boot_cpu_pda[];
df79efde	36
365ba917	37	#define cpu_pda(i) (_cpu_pda[i])
1da177e4 LT	38
	39	/*
	40	* There is no fast way to get the base address of the PDA, all the accesses
	41	* have to mention %fs/%gs. So it needs to be done this Torvaldian way.
	42	*/
fd167e42	43	extern void __bad_pda_field(void) __attribute__((noreturn));
1da177e4	44
c1a9d41f AK	45	/*
	46	* proxy_pda doesn't actually exist, but tell gcc it is accessed for
	47	* all PDA accesses so it gets read/write dependencies right.
	48	*/
53ee11ae AK	49	extern struct x8664_pda _proxy_pda;
53ee11ae AK	50
1da177e4 LT	51	#define pda_offset(field) offsetof(struct x8664_pda, field)
1da177e4 LT	52
c1a9d41f AK	53	#define pda_to_op(op,field,val) do { \
	54	typedef typeof(_proxy_pda.field) T__; \
	55	if (0) { T__ tmp__; tmp__ = (val); } /* type checking */ \
	56	switch (sizeof(_proxy_pda.field)) { \
	57	case 2: \
	58	asm(op "w %1,%%gs:%c2" : \
	59	"+m" (_proxy_pda.field) : \
	60	"ri" ((T__)val), \
	61	"i"(pda_offset(field))); \
	62	break; \
	63	case 4: \
	64	asm(op "l %1,%%gs:%c2" : \
	65	"+m" (_proxy_pda.field) : \
	66	"ri" ((T__)val), \
	67	"i" (pda_offset(field))); \
	68	break; \
	69	case 8: \
	70	asm(op "q %1,%%gs:%c2": \
	71	"+m" (_proxy_pda.field) : \
	72	"ri" ((T__)val), \
	73	"i"(pda_offset(field))); \
	74	break; \
	75	default: \
	76	__bad_pda_field(); \
	77	} \
1da177e4 LT	78	} while (0)
1da177e4 LT	79
c1a9d41f AK	80	#define pda_from_op(op,field) ({ \
	81	typeof(_proxy_pda.field) ret__; \
	82	switch (sizeof(_proxy_pda.field)) { \
	83	case 2: \
	84	asm(op "w %%gs:%c1,%0" : \
	85	"=r" (ret__) : \
	86	"i" (pda_offset(field)), \
	87	"m" (_proxy_pda.field)); \
	88	break; \
	89	case 4: \
	90	asm(op "l %%gs:%c1,%0": \
	91	"=r" (ret__): \
	92	"i" (pda_offset(field)), \
	93	"m" (_proxy_pda.field)); \
	94	break; \
	95	case 8: \
	96	asm(op "q %%gs:%c1,%0": \
	97	"=r" (ret__) : \
	98	"i" (pda_offset(field)), \
	99	"m" (_proxy_pda.field)); \
	100	break; \
	101	default: \
	102	__bad_pda_field(); \
	103	} \
1da177e4 LT	104	ret__; })
1da177e4 LT	105
1da177e4 LT	106	#define read_pda(field) pda_from_op("mov",field)
	107	#define write_pda(field,val) pda_to_op("mov",field,val)
	108	#define add_pda(field,val) pda_to_op("add",field,val)
	109	#define sub_pda(field,val) pda_to_op("sub",field,val)
3f74478b	110	#define or_pda(field,val) pda_to_op("or",field,val)
1da177e4	111
9446868b AK	112	/* This is not atomic against other CPUs -- CPU preemption needs to be off */
	113	#define test_and_clear_bit_pda(bit,field) ({ \
	114	int old__; \
	115	asm volatile("btr %2,%%gs:%c3\n\tsbbl %0,%0" \
	116	: "=r" (old__), "+m" (_proxy_pda.field) \
	117	: "dIr" (bit), "i" (pda_offset(field)) : "memory"); \
	118	old__; \
	119	})
	120
1da177e4 LT	121	#endif
	122
	123	#define PDA_STACKOFFSET (5*8)
	124
	125	#endif