1991/0703/pc/mem.h (diff list | history)

1991/0629/sys/src/9/pc/mem.h:59,68 – 1991/0703/sys/src/9/pc/mem.h:59,68 (short | long | prev | next)
1991/0613		*/
1991/0625		#define NULLSEG 0 /* null segment */ #define KESEG 1 /* kernel executable */ #define KDSEG 2 /* kernel data/stack */ #define UESEG 3 /* user executable */ #define UDSEG 4 /* user data/stack */
1991/0703		#define KDSEG 1 /* kernel data/stack */ #define KESEG 2 /* kernel executable */ #define UDSEG 3 /* user data/stack */ #define UESEG 4 /* user executable */
1991/0625		#define SYSGATE 5 /* system call gate */ #define SELGDT (0<<3) /* selector is in gdt */
1991/0629/sys/src/9/pc/mem.h:86,91 – 1991/0703/sys/src/9/pc/mem.h:86,92
1991/0627		#define SEGCG (0x0C<<8) /* call gate */ #define SEGIG (0x0E<<8) /* interrupt gate */ #define SEGTG (0x0F<<8) /* task gate */
1991/0703		#define SEGTYPE (0x1F<<8)
1991/0627		#define SEGP (1<<15) /* segment present */ #define SEGPL(x) ((x)<<13) /* priority level */