35 lines
859 B
C
35 lines
859 B
C
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/*
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* p->mem:
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* text
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* original data and bss
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* fixed-size stack
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* expandable heap
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*/
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/*
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* segments in proc->gdt
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*/
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#define SEG_KCODE 1 // kernel code
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#define SEG_KDATA 2 // kernel data+stack
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#define SEG_UCODE 3
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#define SEG_UDATA 4
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#define SEG_TSS 5 // this process's task state
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#define NSEGS 6
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struct proc{
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char *mem; // start of process's physical memory
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unsigned sz; // total size of mem, including kernel stack
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char *kstack; // kernel stack, separate from mem so it doesn't move
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enum { UNUSED, RUNNABLE, WAITING } state;
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struct Taskstate ts; // only to give cpu address of kernel stack
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struct Segdesc gdt[NSEGS];
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struct Pseudodesc gdt_pd;
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unsigned esp; // kernel stack pointer
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unsigned ebp; // kernel frame pointer
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struct Trapframe *tf; // points into kstack, used to find user regs
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};
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extern struct proc proc[];
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