The patch titled i386-pda: Basic definitions for i386-pda has been added to the -mm tree. Its filename is i386-pda-basic-definitions-for-i386-pda.patch See http://www.zip.com.au/~akpm/linux/patches/stuff/added-to-mm.txt to find out what to do about this ------------------------------------------------------ Subject: i386-pda: Basic definitions for i386-pda From: Jeremy Fitzhardinge <jeremy@xxxxxxxx> This patch has the basic definitions of struct i386_pda, and the segment selector in the GDT. asm-i386/pda.h is more or less a direct copy of asm-x86_64/pda.h. The most interesting difference is the use of _proxy_pda, which is used to give gcc a model for the actual memory operations on the real pda structure. No actual reference is ever made to _proxy_pda, so it is never defined. Signed-off-by: Jeremy Fitzhardinge <jeremy@xxxxxxxxxxxxx> Cc: Chuck Ebbert <76306.1226@xxxxxxxxxxxxxx> Cc: Zachary Amsden <zach@xxxxxxxxxx> Cc: Jan Beulich <jbeulich@xxxxxxxxxx> Cc: Andi Kleen <ak@xxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxx> --- arch/i386/kernel/head.S | 2 include/asm-i386/pda.h | 95 +++++++++++++++++++++++++++++++++++ include/asm-i386/segment.h | 5 + 3 files changed, 100 insertions(+), 2 deletions(-) diff -puN arch/i386/kernel/head.S~i386-pda-basic-definitions-for-i386-pda arch/i386/kernel/head.S --- a/arch/i386/kernel/head.S~i386-pda-basic-definitions-for-i386-pda +++ a/arch/i386/kernel/head.S @@ -585,7 +585,7 @@ ENTRY(cpu_gdt_table) .quad 0x004092000000ffff /* 0xc8 APM DS data */ .quad 0x00c0920000000000 /* 0xd0 - ESPFIX SS */ - .quad 0x0000000000000000 /* 0xd8 - unused */ + .quad 0x0000000000000000 /* 0xd8 - PDA */ .quad 0x0000000000000000 /* 0xe0 - unused */ .quad 0x0000000000000000 /* 0xe8 - unused */ .quad 0x0000000000000000 /* 0xf0 - unused */ diff -puN /dev/null include/asm-i386/pda.h --- /dev/null +++ a/include/asm-i386/pda.h @@ -0,0 +1,95 @@ +/* + Per-processor Data Areas + Jeremy Fitzhardinge <jeremy@xxxxxxxx> 2006 + Based on asm-x86_64/pda.h by Andi Kleen. + */ +#ifndef _I386_PDA_H +#define _I386_PDA_H + +#include <linux/stddef.h> + +struct i386_pda +{ + struct i386_pda *_pda; /* pointer to self */ +}; + +extern struct i386_pda *_cpu_pda[]; + +#define cpu_pda(i) (_cpu_pda[i]) + +#define pda_offset(field) offsetof(struct i386_pda, field) + +extern void __bad_pda_field(void); + +/* This variable is never instantiated. It is only used as a stand-in + for the real per-cpu PDA memory, so that gcc can understand what + memory operations the inline asms() below are performing. This + eliminates the need to make the asms volatile or have memory + clobbers, so gcc can readily analyse them. */ +extern struct i386_pda _proxy_pda; + +#define pda_to_op(op,field,val) \ + do { \ + typedef typeof(_proxy_pda.field) T__; \ + if (0) { T__ tmp__; tmp__ = (val); } \ + switch (sizeof(_proxy_pda.field)) { \ + case 1: \ + asm(op "b %1,%%gs:%c2" \ + : "+m" (_proxy_pda.field) \ + :"ri" ((T__)val), \ + "i"(pda_offset(field))); \ + break; \ + 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; \ + default: __bad_pda_field(); \ + } \ + } while (0) + +#define pda_from_op(op,field) \ + ({ \ + typeof(_proxy_pda.field) ret__; \ + switch (sizeof(_proxy_pda.field)) { \ + case 1: \ + asm(op "b %%gs:%c1,%0" \ + : "=r" (ret__) \ + : "i" (pda_offset(field)), \ + "m" (_proxy_pda.field)); \ + break; \ + 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; \ + default: __bad_pda_field(); \ + } \ + ret__; }) + +/* Return a pointer to a pda field */ +#define pda_addr(field) \ + ((typeof(_proxy_pda.field) *)((unsigned char *)read_pda(_pda) + \ + pda_offset(field))) + +#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 /* _I386_PDA_H */ diff -puN include/asm-i386/segment.h~i386-pda-basic-definitions-for-i386-pda include/asm-i386/segment.h --- a/include/asm-i386/segment.h~i386-pda-basic-definitions-for-i386-pda +++ a/include/asm-i386/segment.h @@ -39,7 +39,7 @@ * 25 - APM BIOS support * * 26 - ESPFIX small SS - * 27 - unused + * 27 - PDA [ per-cpu private data area ] * 28 - unused * 29 - unused * 30 - unused @@ -74,6 +74,9 @@ #define GDT_ENTRY_ESPFIX_SS (GDT_ENTRY_KERNEL_BASE + 14) #define __ESPFIX_SS (GDT_ENTRY_ESPFIX_SS * 8) +#define GDT_ENTRY_PDA (GDT_ENTRY_KERNEL_BASE + 15) +#define __KERNEL_PDA (GDT_ENTRY_PDA * 8) + #define GDT_ENTRY_DOUBLEFAULT_TSS 31 /* _ Patches currently in -mm which might be from jeremy@xxxxxxxx are x86-remove-default_ldt-and-simplify-ldt-setting.patch i386-use-asm-offsets-for-the-offsets-of-registers-into-the-pt_regs-struct-rather-than-having-hard-coded-constants.patch i386-pda-basic-definitions-for-i386-pda.patch i386-pda-initialize-the-per-cpu-data-area.patch i386-pda-use-%gs-as-the-pda-base-segment-in-the-kernel.patch i386-pda-fix-places-where-using-%gs-changes-the-usermode-abi.patch i386-pda-update-sys_vm86-to-cope-with-changed-pt_regs-and-%gs-usage.patch i386-pda-implement-smp_processor_id-with-the-pda.patch i386-pda-implement-current-with-the-pda.patch i386-pda-store-the-interrupt-regs-pointer-in-the-pda.patch generic-bug-implementation.patch generic-bug-for-i386.patch generic-bug-for-x86-64.patch generic-bug-for-powerpc.patch uml-add-generic-bug-support.patch use-generic-bug-for-ppc.patch bug-test-1.patch - To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html