projects / mirror_ubuntu-artful-kernel.git / blame
| Commit | Line | Data |
|---|---|---|
| 9ca36101 JF |
1 | /* |
| 2 | Per-processor Data Areas | |
| 3 | Jeremy Fitzhardinge <jeremy@goop.org> 2006 | |
| 4 | Based on asm-x86_64/pda.h by Andi Kleen. | |
| 5 | */ | |
| 6 | #ifndef _I386_PDA_H | |
| 7 | #define _I386_PDA_H | |
| 8 | ||
| 9 | #include <linux/stddef.h> | |
| ec7fcaab | 10 | #include <linux/types.h> |
| 9ca36101 JF |
11 | |
| 12 | struct i386_pda | |
| 13 | { | |
| 14 | struct i386_pda *_pda; /* pointer to self */ | |
| b2938f88 JF |
15 | |
| 16 | int cpu_number; | |
| ec7fcaab | 17 | struct task_struct *pcurrent; /* current process */ |
| 70463dac | 18 | struct pt_regs *irq_regs; |
| 9ca36101 JF |
19 | }; |
| 20 | ||
| 21 | extern struct i386_pda *_cpu_pda[]; | |
| 22 | ||
| 23 | #define cpu_pda(i) (_cpu_pda[i]) | |
| 24 | ||
| 25 | #define pda_offset(field) offsetof(struct i386_pda, field) | |
| 26 | ||
| 27 | extern void __bad_pda_field(void); | |
| 28 | ||
| 29 | /* This variable is never instantiated. It is only used as a stand-in | |
| 30 | for the real per-cpu PDA memory, so that gcc can understand what | |
| 31 | memory operations the inline asms() below are performing. This | |
| 32 | eliminates the need to make the asms volatile or have memory | |
| 33 | clobbers, so gcc can readily analyse them. */ | |
| 34 | extern struct i386_pda _proxy_pda; | |
| 35 | ||
| 36 | #define pda_to_op(op,field,val) \ | |
| 37 | do { \ | |
| 38 | typedef typeof(_proxy_pda.field) T__; \ | |
| 39 | if (0) { T__ tmp__; tmp__ = (val); } \ | |
| 40 | switch (sizeof(_proxy_pda.field)) { \ | |
| 41 | case 1: \ | |
| 464d1a78 | 42 | asm(op "b %1,%%fs:%c2" \ |
| 9ca36101 JF |
43 | : "+m" (_proxy_pda.field) \ |
| 44 | :"ri" ((T__)val), \ | |
| 45 | "i"(pda_offset(field))); \ | |
| 46 | break; \ | |
| 47 | case 2: \ | |
| 464d1a78 | 48 | asm(op "w %1,%%fs:%c2" \ |
| 9ca36101 JF |
49 | : "+m" (_proxy_pda.field) \ |
| 50 | :"ri" ((T__)val), \ | |
| 51 | "i"(pda_offset(field))); \ | |
| 52 | break; \ | |
| 53 | case 4: \ | |
| 464d1a78 | 54 | asm(op "l %1,%%fs:%c2" \ |
| 9ca36101 JF |
55 | : "+m" (_proxy_pda.field) \ |
| 56 | :"ri" ((T__)val), \ | |
| 57 | "i"(pda_offset(field))); \ | |
| 58 | break; \ | |
| 59 | default: __bad_pda_field(); \ | |
| 60 | } \ | |
| 61 | } while (0) | |
| 62 | ||
| 63 | #define pda_from_op(op,field) \ | |
| 64 | ({ \ | |
| 65 | typeof(_proxy_pda.field) ret__; \ | |
| 66 | switch (sizeof(_proxy_pda.field)) { \ | |
| 67 | case 1: \ | |
| 464d1a78 | 68 | asm(op "b %%fs:%c1,%0" \ |
| 9ca36101 JF |
69 | : "=r" (ret__) \ |
| 70 | : "i" (pda_offset(field)), \ | |
| 71 | "m" (_proxy_pda.field)); \ | |
| 72 | break; \ | |
| 73 | case 2: \ | |
| 464d1a78 | 74 | asm(op "w %%fs:%c1,%0" \ |
| 9ca36101 JF |
75 | : "=r" (ret__) \ |
| 76 | : "i" (pda_offset(field)), \ | |
| 77 | "m" (_proxy_pda.field)); \ | |
| 78 | break; \ | |
| 79 | case 4: \ | |
| 464d1a78 | 80 | asm(op "l %%fs:%c1,%0" \ |
| 9ca36101 JF |
81 | : "=r" (ret__) \ |
| 82 | : "i" (pda_offset(field)), \ | |
| 83 | "m" (_proxy_pda.field)); \ | |
| 84 | break; \ | |
| 85 | default: __bad_pda_field(); \ | |
| 86 | } \ | |
| 87 | ret__; }) | |
| 88 | ||
| 89 | /* Return a pointer to a pda field */ | |
| 90 | #define pda_addr(field) \ | |
| 91 | ((typeof(_proxy_pda.field) *)((unsigned char *)read_pda(_pda) + \ | |
| 92 | pda_offset(field))) | |
| 93 | ||
| 94 | #define read_pda(field) pda_from_op("mov",field) | |
| 95 | #define write_pda(field,val) pda_to_op("mov",field,val) | |
| 96 | #define add_pda(field,val) pda_to_op("add",field,val) | |
| 97 | #define sub_pda(field,val) pda_to_op("sub",field,val) | |
| 98 | #define or_pda(field,val) pda_to_op("or",field,val) | |
| 99 | ||
| 100 | #endif /* _I386_PDA_H */ |