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BOOK.TXT：源码内容

04336 #define NMI_VECTOR 2 /* non-maskable interrupt */
04337 #define BREAKPOINT_VECTOR 3 /* software breakpoint */
04338 #define OVERFLOW_VECTOR 4 /* from INTO */
04339
04340 /* Fixed system call vector. */
04341 #define SYS_VECTOR 32 /* system calls are made with int SYSVEC */
04342 #define SYS386_VECTOR 33 /* except 386 system calls use this */
04343 #define LEVEL0_VECTOR 34 /* for execution of a function at level 0 */
04344
04345 /* Suitable irq bases for hardware interrupts. Reprogram the 8259(s) from
04346 * the PC BIOS defaults since the BIOS doesn't respect all the processor's
04347 * reserved vectors (0 to 31).
04348 */
04349 #define BIOS_IRQ0_VEC 0x08 /* base of IRQ0-7 vectors used by BIOS */
04350 #define BIOS_IRQ8_VEC 0x70 /* base of IRQ8-15 vectors used by BIOS */
04351 #define IRQ0_VECTOR 0x28 /* more or less arbitrary, but > SYS_VECTOR */
04352 #define IRQ8_VECTOR 0x30 /* together for simplicity */
04353
04354 /* Hardware interrupt numbers. */
04355 #define NR_IRQ_VECTORS 16
04356 #define CLOCK_IRQ 0
04357 #define KEYBOARD_IRQ 1
04358 #define CASCADE_IRQ 2 /* cascade enable for 2nd AT controller */
04359 #define ETHER_IRQ 3 /* default ethernet interrupt vector */
04360 #define SECONDARY_IRQ 3 /* RS232 interrupt vector for port 2 */
04361 #define RS232_IRQ 4 /* RS232 interrupt vector for port 1 */
04362 #define XT_WINI_IRQ 5 /* xt winchester */
04363 #define FLOPPY_IRQ 6 /* floppy disk */
04364 #define PRINTER_IRQ 7
04365 #define AT_WINI_IRQ 14 /* at winchester */
04366
04367 /* Interrupt number to hardware vector. */
04368 #define BIOS_VECTOR(irq)
04369 (((irq) < 8 ? BIOS_IRQ0_VEC : BIOS_IRQ8_VEC) + ((irq) & 0x07))
04370 #define VECTOR(irq)
04371 (((irq) < 8 ? IRQ0_VECTOR : IRQ8_VECTOR) + ((irq) & 0x07))
04372
04373 /* BIOS hard disk parameter vectors. */
04374 #define WINI_0_PARM_VEC 0x41
04375 #define WINI_1_PARM_VEC 0x46
04376
04377 /* 8259A interrupt controller ports. */
04378 #define INT_CTL 0x20 /* I/O port for interrupt controller */
04379 #define INT_CTLMASK 0x21 /* setting bits in this port disables ints */
04380 #define INT2_CTL 0xA0 /* I/O port for second interrupt controller */
04381 #define INT2_CTLMASK 0xA1 /* setting bits in this port disables ints */
04382
04383 /* Magic numbers for interrupt controller. */
04384 #define ENABLE 0x20 /* code used to re-enable after an interrupt */
04385
04386 /* Sizes of memory tables. */
04387 #define NR_MEMS 3 /* number of chunks of memory */
04388
04389 /* Miscellaneous ports. */
04390 #define PCR 0x65 /* Planar Control Register */
04391 #define PORT_B 0x61 /* I/O port for 8255 port B (kbd, beeper...) */
04392 #define TIMER0 0x40 /* I/O port for timer channel 0 */
04393 #define TIMER2 0x42 /* I/O port for timer channel 2 */
04394 #define TIMER_MODE 0x43 /* I/O port for timer mode control */
04395
04396 #endif /* (CHIP == INTEL) */
04397
04398 #if (CHIP == M68000)
04399
04400 #define K_STACK_BYTES 1024 /* how many bytes for the kernel stack */
04401
04402 /* Sizes of memory tables. */
04403 #define NR_MEMS 2 /* number of chunks of memory */
04404
04405 /* p_reg contains: d0-d7, a0-a6, in that order. */
04406 #define NR_REGS 15 /* number of general regs in each proc slot */
04407
04408 #define TRACEBIT 0x8000 /* or this with psw in proc[] for tracing */
04409 #define SETPSW(rp, new) /* permits only certain bits to be set */
04410 ((rp)->p_reg.psw = (rp)->p_reg.psw & ~0xFF | (new) & 0xFF)
04411
04412 #define MEM_BYTES 0xffffffff /* memory size for /dev/mem */
04413
04414 #ifdef __ACK__
04415 #define FSTRUCOPY
04416 #endif
04417
04418 #endif /* (CHIP == M68000) */
04419
04420 /* The following items pertain to the scheduling queues. */
04421 #define TASK_Q 0 /* ready tasks are scheduled via queue 0 */
04422 #define SERVER_Q 1 /* ready servers are scheduled via queue 1 */
04423 #define USER_Q 2 /* ready users are scheduled via queue 2 */
04424
04425 #if (MACHINE == ATARI)
04426 #define SHADOW_Q 3 /* runnable, but shadowed processes */
04427 #define NQ 4 /* # of scheduling queues */
04428 #else
04429 #define NQ 3 /* # of scheduling queues */
04430 #endif
04431
04432 /* Env_parse() return values. */
04433 #define EP_UNSET 0 /* variable not set */
04434 #define EP_OFF 1 /* var = off */
04435 #define EP_ON 2 /* var = on (or field left blank) */
04436 #define EP_SET 3 /* var = 1:2:3 (nonblank field) */
04437
04438 /* To translate an address in kernel space to a physical address. This is
04439 * the same as umap(proc_ptr, D, vir, sizeof(*vir)), but a lot less costly.
04440 */
04441 #define vir2phys(vir) (data_base + (vir_bytes) (vir))
04442
04443 #define printf printk /* the kernel really uses printk, not printf */
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
src/kernel/type.h
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
04500 #ifndef TYPE_H
04501 #define TYPE_H
04502
04503 typedef _PROTOTYPE( void task_t, (void) );
04504 typedef _PROTOTYPE( int (*rdwt_t), (message *m_ptr) );
04505 typedef _PROTOTYPE( void (*watchdog_t), (void) );
04506
04507 struct tasktab {
04508 task_t *initial_pc;
04509 int stksize;
04510 char name[8];
04511 };
04512
04513 struct memory {
04514 phys_clicks base;
04515 phys_clicks size;
04516 };
04517
04518 /* Administration for clock polling. */
04519 struct milli_state {
04520 unsigned long accum_count; /* accumulated clock ticks */
04521 unsigned prev_count; /* previous clock value */
04522 };
04523
04524 #if (CHIP == INTEL)
04525 typedef unsigned port_t;
04526 typedef unsigned segm_t;
04527 typedef unsigned reg_t; /* machine register */
04528
04529 /* The stack frame layout is determined by the software, but for efficiency
04530 * it is laid out so the assembly code to use it is as simple as possible.
04531 * 80286 protected mode and all real modes use the same frame, built with
04532 * 16-bit registers. Real mode lacks an automatic stack switch, so little
04533 * is lost by using the 286 frame for it. The 386 frame differs only in
04534 * having 32-bit registers and more segment registers. The same names are
04535 * used for the larger registers to avoid differences in the code.
04536 */
04537 struct stackframe_s { /* proc_ptr points here */
04538 #if _WORD_SIZE == 4
04539 u16_t gs; /* last item pushed by save */
04540 u16_t fs; /* ^ */
04541 #endif
04542 u16_t es; /* | */
04543 u16_t ds; /* | */
04544 reg_t di; /* di through cx are not accessed in C */
04545 reg_t si; /* order is to match pusha/popa */
04546 reg_t fp; /* bp */
04547 reg_t st; /* hole for another copy of sp */
04548 reg_t bx; /* | */
04549 reg_t dx; /* | */
04550 reg_t cx; /* | */
04551 reg_t retreg; /* ax and above are all pushed by save */
04552 reg_t retadr; /* return address for assembly code save() */
04553 reg_t pc; /* ^ last item pushed by interrupt */
04554 reg_t cs; /* | */
04555 reg_t psw; /* | */
04556 reg_t sp; /* | */
04557 reg_t ss; /* these are pushed by CPU during interrupt */
04558 };
04559
04560 struct segdesc_s { /* segment descriptor for protected mode */
04561 u16_t limit_low;
04562 u16_t base_low;
04563 u8_t base_middle;
04564 u8_t access; /* |P|DL|1|X|E|R|A| */
04565 #if _WORD_SIZE == 4
04566 u8_t granularity; /* |G|X|0|A|LIMT| */
04567 u8_t base_high;
04568 #else
04569 u16_t reserved;
04570 #endif
04571 };
04572
04573 typedef _PROTOTYPE( int (*irq_handler_t), (int irq) );
04574
04575 #endif /* (CHIP == INTEL) */
04576
04577 #if (CHIP == M68000)
04578 typedef _PROTOTYPE( void (*dmaint_t), (void) );
04579
04580 typedef u32_t reg_t; /* machine register */
04581
04582 /* The name and fields of this struct were chosen for PC compatibility. */
04583 struct stackframe_s {
04584 reg_t retreg; /* d0 */
04585 reg_t d1;
04586 reg_t d2;
04587 reg_t d3;
04588 reg_t d4;
04589 reg_t d5;
04590 reg_t d6;
04591 reg_t d7;
04592 reg_t a0;
04593 reg_t a1;
04594 reg_t a2;
04595 reg_t a3;
04596 reg_t a4;
04597 reg_t a5;
04598 reg_t fp; /* also known as a6 */
04599 reg_t sp; /* also known as a7 */
04600 reg_t pc;
04601 u16_t psw;
04602 u16_t dummy; /* make size multiple of reg_t for system.c */
04603 };
04604
04605 struct fsave {
04606 struct cpu_state {
04607 u16_t i_format;
04608 u32_t i_addr;
04609 u16_t i_state[4];
04610 } cpu_state;
04611 struct state_frame {
04612 u8_t frame_type;
04613 u8_t frame_size;
04614 u16_t reserved;
04615 u8_t frame[212];
04616 } state_frame;
04617 struct fpp_model {
04618 u32_t fpcr;
04619 u32_t fpsr;
04620 u32_t fpiar;
04621 struct fpN {
04622 u32_t high;
04623 u32_t low;
04624 u32_t mid;
04625 } fpN[8];
04626 } fpp_model;
04627 };
04628 #endif /* (CHIP == M68000) */
04629
04630 #endif /* TYPE_H */
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
src/kernel/proto.h
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
04700 /* Function prototypes. */
04701
04702 #ifndef PROTO_H
04703 #define PROTO_H
04704
04705 /* Struct declarations. */
04706 struct proc;
04707 struct tty;
04708
04709 /* at_wini.c, wini.c */
04710 _PROTOTYPE( void winchester_task, (void) );
04711 _PROTOTYPE( void at_winchester_task, (void) );
04712
04713 /* clock.c */
04714 _PROTOTYPE( void clock_task, (void) );
04715 _PROTOTYPE( void clock_stop, (void) );
04716 _PROTOTYPE( clock_t get_uptime, (void) );
04717 _PROTOTYPE( void syn_alrm_task, (void) );
04718
04719 /* dmp.c */
04720 _PROTOTYPE( void map_dmp, (void) );
04721 _PROTOTYPE( void p_dmp, (void) );
04722 _PROTOTYPE( void reg_dmp, (struct proc *rp) );
04723
04724 /* dp8390.c */
04725 _PROTOTYPE( void dp8390_task, (void) );
04726 _PROTOTYPE( void dp_dump, (void) );
04727 _PROTOTYPE( void dp8390_stop, (void) );
04728
04729 /* floppy.c, stfloppy.c */
04730 _PROTOTYPE( void floppy_task, (void) );
04731 _PROTOTYPE( void floppy_stop, (void) );
04732
04733 /* main.c, stmain.c */
04734 _PROTOTYPE( void main, (void) );
04735 _PROTOTYPE( void panic, (const char *s, int n) );
04736
04737 /* memory.c */
04738 _PROTOTYPE( void mem_task, (void) );
04739
04740 /* misc.c */
04741 _PROTOTYPE( int env_parse, (char *env, char *fmt, int field,
04742 long *param, long min, long max) );
04743
04744 /* printer.c, stprint.c */
04745 _PROTOTYPE( void printer_task, (void) );
04746
04747 /* proc.c */
04748 _PROTOTYPE( void interrupt, (int task) );
04749 _PROTOTYPE( int lock_mini_send, (struct proc *caller_ptr,
04750 int dest, message *m_ptr) );
04751 _PROTOTYPE( void lock_pick_proc, (void) );
04752 _PROTOTYPE( void lock_ready, (struct proc *rp) );
04753 _PROTOTYPE( void lock_sched, (void) );
04754 _PROTOTYPE( void lock_unready, (struct proc *rp) );
04755 _PROTOTYPE( int sys_call, (int function, int src_dest, message *m_ptr) );
04756 _PROTOTYPE( void unhold, (void) );
04757
04758 /* rs232.c */
04759 _PROTOTYPE( void rs_init, (struct tty *tp) );
04760
04761 /* system.c */
04762 _PROTOTYPE( void cause_sig, (int proc_nr, int sig_nr) );
04763 _PROTOTYPE( void inform, (void) );
04764 _PROTOTYPE( phys_bytes numap, (int proc_nr, vir_bytes vir_addr,
04765 vir_bytes bytes) );
04766 _PROTOTYPE( void sys_task, (void) );
04767 _PROTOTYPE( phys_bytes umap, (struct proc *rp, int seg, vir_bytes vir_addr,
04768 vir_bytes bytes) );
04769
04770 /* tty.c */
04771 _PROTOTYPE( void handle_events, (struct tty *tp) );
04772 _PROTOTYPE( void sigchar, (struct tty *tp, int sig) );
04773 _PROTOTYPE( void tty_task, (void) );
04774 _PROTOTYPE( int in_process, (struct tty *tp, char *buf, int count) );
04775 _PROTOTYPE( void out_process, (struct tty *tp, char *bstart, char *bpos,
04776 char *bend, int *icount, int *ocount) );
04777 _PROTOTYPE( void tty_wakeup, (clock_t now) );
04778 _PROTOTYPE( void tty_reply, (int code, int replyee, int proc_nr,
04779 int status) );
04780 _PROTOTYPE( void tty_devnop, (struct tty *tp) );
04781
04782 /* library */
04783 _PROTOTYPE( void *memcpy, (void *_s1, const void *_s2, size_t _n) );
04784
04785 #if (CHIP == INTEL)
04786
04787 /* clock.c */
04788 _PROTOTYPE( void milli_start, (struct milli_state *msp) );
04789 _PROTOTYPE( unsigned milli_elapsed, (struct milli_state *msp) );
04790 _PROTOTYPE( void milli_delay, (unsigned millisec) );
04791
04792 /* console.c */
04793 _PROTOTYPE( void cons_stop, (void) );
04794 _PROTOTYPE( void putk, (int c) );
04795 _PROTOTYPE( void scr_init, (struct tty *tp) );
04796 _PROTOTYPE( void toggle_scroll, (void) );
04797 _PROTOTYPE( int con_loadfont, (phys_bytes user_phys) );
04798 _PROTOTYPE( void select_console, (int cons_line) );
04799
04800 /* cstart.c */
04801 _PROTOTYPE( void cstart, (U16_t cs, U16_t ds, U16_t mcs, U16_t mds,
04802 U16_t parmoff, U16_t parmsize) );
04803 _PROTOTYPE( char *k_getenv, (char *name) );
04804
04805 /* exception.c */
04806 _PROTOTYPE( void exception, (unsigned vec_nr) );
04807
04808 /* i8259.c */
04809 _PROTOTYPE( irq_handler_t get_irq_handler, (int irq) );
04810 _PROTOTYPE( void put_irq_handler, (int irq, irq_handler_t handler) );
04811 _PROTOTYPE( void intr_init, (int mine) );
04812
04813 /* keyboard.c */
04814 _PROTOTYPE( void kb_init, (struct tty *tp) );
04815 _PROTOTYPE( int kbd_loadmap, (phys_bytes user_phys) );
04816 _PROTOTYPE( void wreboot, (int how) );
04817
04818 /* klib*.s */
04819 _PROTOTYPE( void bios13, (void) );
04820 _PROTOTYPE( phys_bytes check_mem, (phys_bytes base, phys_bytes size) );
04821 _PROTOTYPE( void cp_mess, (int src,phys_clicks src_clicks,vir_bytes src_offset,
04822 phys_clicks dst_clicks, vir_bytes dst_offset) );
04823 _PROTOTYPE( int in_byte, (port_t port) );
04824 _PROTOTYPE( int in_word, (port_t port) );
04825 _PROTOTYPE( void lock, (void) );
04826 _PROTOTYPE( void unlock, (void) );
04827 _PROTOTYPE( void enable_irq, (unsigned irq) );
04828 _PROTOTYPE( int disable_irq, (unsigned irq) );
04829 _PROTOTYPE( u16_t mem_rdw, (segm_t segm, vir_bytes offset) );
04830 _PROTOTYPE( void out_byte, (port_t port, int value) );
04831 _PROTOTYPE( void out_word, (port_t port, int value) );
04832 _PROTOTYPE( void phys_copy, (phys_bytes source, phys_bytes dest,
04833 phys_bytes count) );
04834 _PROTOTYPE( void port_read, (unsigned port, phys_bytes destination,
04835 unsigned bytcount) );
04836 _PROTOTYPE( void port_read_byte, (unsigned port, phys_bytes destination,
04837 unsigned bytcount) );
04838 _PROTOTYPE( void port_write, (unsigned port, phys_bytes source,
04839 unsigned bytcount) );
04840 _PROTOTYPE( void port_write_byte, (unsigned port, phys_bytes source,
04841 unsigned bytcount) );
04842 _PROTOTYPE( void reset, (void) );
04843 _PROTOTYPE( void vid_vid_copy, (unsigned src, unsigned dst, unsigned count));
04844 _PROTOTYPE( void mem_vid_copy, (u16_t *src, unsigned dst, unsigned count));
04845 _PROTOTYPE( void level0, (void (*func)(void)) );
04846 _PROTOTYPE( void monitor, (void) );
04847
04848 /* misc.c */
04849 _PROTOTYPE( void mem_init, (void) );
04850
04851 /* mpx*.s */
04852 _PROTOTYPE( void idle_task, (void) );
04853 _PROTOTYPE( void restart, (void) );
04854
04855 /* The following are never called from C (pure asm procs). */
04856
04857 /* Exception handlers (real or protected mode), in numerical order. */
04858 void _PROTOTYPE( int00, (void) ), _PROTOTYPE( divide_error, (void) );
04859 void _PROTOTYPE( int01, (void) ), _PROTOTYPE( single_step_exception, (void) );
04860 void _PROTOTYPE( int02, (void) ), _PROTOTYPE( nmi, (void) );
04861 void _PROTOTYPE( int03, (void) ), _PROTOTYPE( breakpoint_exception, (void) );
04862 void _PROTOTYPE( int04, (void) ), _PROTOTYPE( overflow, (void) );
04863 void _PROTOTYPE( int05, (void) ), _PROTOTYPE( bounds_check, (void) );
04864 void _PROTOTYPE( int06, (void) ), _PROTOTYPE( inval_opcode, (void) );
04865 void _PROTOTYPE( int07, (void) ), _PROTOTYPE( copr_not_available, (void) );
04866 void _PROTOTYPE( double_fault, (void) );
04867 void _PROTOTYPE( copr_seg_overrun, (void) );
04868 void _PROTOTYPE( inval_tss, (void) );
04869 void _PROTOTYPE( segment_not_present, (void) );
04870 void _PROTOTYPE( stack_exception, (void) );
04871 void _PROTOTYPE( general_protection, (void) );
04872 void _PROTOTYPE( page_fault, (void) );
04873 void _PROTOTYPE( copr_error, (void) );
04874
04875 /* Hardware interrupt handlers. */
04876 _PROTOTYPE( void hwint00, (void) );
04877 _PROTOTYPE( void hwint01, (void) );
04878 _PROTOTYPE( void hwint02, (void) );
04879 _PROTOTYPE( void hwint03, (void) );
04880 _PROTOTYPE( void hwint04, (void) );
04881 _PROTOTYPE( void hwint05, (void) );
04882 _PROTOTYPE( void hwint06, (void) );
04883 _PROTOTYPE( void hwint07, (void) );
04884 _PROTOTYPE( void hwint08, (void) );
04885 _PROTOTYPE( void hwint09, (void) );
04886 _PROTOTYPE( void hwint10, (void) );
04887 _PROTOTYPE( void hwint11, (void) );
04888 _PROTOTYPE( void hwint12, (void) );
04889 _PROTOTYPE( void hwint13, (void) );
04890 _PROTOTYPE( void hwint14, (void) );
04891 _PROTOTYPE( void hwint15, (void) );
04892
04893 /* Software interrupt handlers, in numerical order. */
04894 _PROTOTYPE( void trp, (void) );
04895 _PROTOTYPE( void s_call, (void) ), _PROTOTYPE( p_s_call, (void) );
04896 _PROTOTYPE( void level0_call, (void) );
04897
04898 /* printer.c */
04899 _PROTOTYPE( void pr_restart, (void) );
04900
04901 /* protect.c */
04902 _PROTOTYPE( void prot_init, (void) );
04903 _PROTOTYPE( void init_codeseg, (struct segdesc_s *segdp, phys_bytes base,
04904 phys_bytes size, int privilege) );
04905 _PROTOTYPE( void init_dataseg, (struct segdesc_s *segdp, phys_bytes base,
04906 phys_bytes size, int privilege) );
04907 _PROTOTYPE( phys_bytes seg2phys, (U16_t seg) );
04908 _PROTOTYPE( void enable_iop, (struct proc *pp) );
04909
04910 /* pty.c */
04911 _PROTOTYPE( void do_pty, (struct tty *tp, message *m_ptr) );
04912 _PROTOTYPE( void pty_init, (struct tty *tp) );
04913
04914 /* system.c */
04915 _PROTOTYPE( void alloc_segments, (struct proc *rp) );
04916
04917 #endif /* (CHIP == INTEL) */
04918
04919 #endif /* PROTO_H */
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
src/kernel/glo.h
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
05000 /* Global variables used in the kernel. */
05001
05002 /* EXTERN is defined as extern except in table.c. */
05003 #ifdef _TABLE
05004 #undef EXTERN
05005 #define EXTERN
05006 #endif
05007
05008 /* Kernel memory. */
05009 EXTERN phys_bytes code_base; /* base of kernel code */
05010 EXTERN phys_bytes data_base; /* base of kernel data */
05011
05012 /* Low level interrupt communications. */
05013 EXTERN struct proc *held_head; /* head of queue of held-up interrupts */
05014 EXTERN struct proc *held_tail; /* tail of queue of held-up interrupts */
05015 EXTERN unsigned char k_reenter; /* kernel reentry count (entry count less 1)*/
05016
05017 /* Process table. Here to stop too many things having to include proc.h. */
05018 EXTERN struct proc *proc_ptr; /* pointer to currently running process */
05019
05020 /* Signals. */
05021 EXTERN int sig_procs; /* number of procs with p_pending != 0 */
05022
05023 /* Memory sizes. */
05024 EXTERN struct memory mem[NR_MEMS]; /* base and size of chunks of memory */
05025 EXTERN phys_clicks tot_mem_size; /* total system memory size */
05026
05027 /* Miscellaneous. */
05028 extern u16_t sizes[]; /* table filled in by boot monitor */
05029 extern struct tasktab tasktab[];/* initialized in table.c, so extern here */
05030 extern char *t_stack[]; /* initialized in table.c, so extern here */
05031 EXTERN unsigned lost_ticks; /* clock ticks counted outside the clock task */
05032 EXTERN clock_t tty_timeout; /* time to wake up the TTY task */
05033 EXTERN int current; /* currently visible console */
05034
05035 #if (CHIP == INTEL)
05036
05037 /* Machine type. */
05038 EXTERN int pc_at; /* PC-AT compatible hardware interface */
05039 EXTERN int ps_mca; /* PS/2 with Micro Channel */
05040 EXTERN unsigned int processor; /* 86, 186, 286, 386, ... */
05041 #if _WORD_SIZE == 2
05042 EXTERN int protected_mode; /* nonzero if running in Intel protected mode*/
05043 #else
05044 #define protected_mode 1 /* 386 mode implies protected mode */
05045 #endif
05046
05047 /* Video card types. */
05048 EXTERN int ega; /* nonzero if console is EGA or VGA */
05049 EXTERN int vga; /* nonzero if console is VGA */
05050
05051 /* Memory sizes. */
05052 EXTERN unsigned ext_memsize; /* initialized by assembler startup code */
05053 EXTERN unsigned low_memsize;
05054
05055 /* Miscellaneous. */
05056 EXTERN irq_handler_t irq_table[NR_IRQ_VECTORS];
05057 EXTERN int irq_use; /* bit map of all in-use irq's */
05058 EXTERN reg_t mon_ss, mon_sp; /* monitor stack */
05059 EXTERN int mon_return; /* true if return to the monitor possible */
05060 EXTERN phys_bytes reboot_code; /* program for the boot monitor */
05061
05062 /* Variables that are initialized elsewhere are just extern here. */
05063 extern struct segdesc_s gdt[]; /* global descriptor table for protected mode*/
05064
05065 EXTERN _PROTOTYPE( void (*level0_func), (void) );
05066 #endif /* (CHIP == INTEL) */
05067
05068 #if (CHIP == M68000)
05069 /* Variables that are initialized elsewhere are just extern here. */
05070 extern int keypad; /* Flag for keypad mode */
05071 extern int app_mode; /* Flag for arrow key application mode */
05072 extern int STdebKey; /* nonzero if ctl-alt-Fx detected */
05073 extern struct tty *cur_cons; /* virtual cons currently displayed */
05074 extern unsigned char font8[]; /* 8 pixel wide font table (initialized) */
05075 extern unsigned char font12[]; /* 12 pixel wide font table (initialized) */
05076 extern unsigned char font16[]; /* 16 pixel wide font table (initialized) */
05077 extern unsigned short resolution; /* screen res; ST_RES_LOW..TT_RES_HIGH */
05078 #endif
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
src/kernel/proc.h
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
05100 #ifndef PROC_H
05101 #define PROC_H
05102
05103 /* Here is the declaration of the process table. It contains the process'
05104 * registers, memory map, accounting, and message send/receive information.
05105 * Many assembly code routines reference fields in it. The offsets to these
05106 * fields are defined in the assembler include file sconst.h. When changing
05107 * 'proc', be sure to change sconst.h to match.
05108 */
05109
05110 struct proc {
05111 struct stackframe_s p_reg; /* process' registers saved in stack frame */
05112
05113 #if (CHIP == INTEL)
05114 reg_t p_ldt_sel; /* selector in gdt giving ldt base and limit*/
05115 struct segdesc_s p_ldt[2]; /* local descriptors for code and data */
05116 /* 2 is LDT_SIZE - avoid include protect.h */
05117 #endif /* (CHIP == INTEL) */
05118
05119 reg_t *p_stguard; /* stack guard word */
05120
05121 int p_nr; /* number of this process (for fast access) */
05122
05123 int p_int_blocked; /* nonzero if int msg blocked by busy task */
05124 int p_int_held; /* nonzero if int msg held by busy syscall */
05125 struct proc *p_nextheld; /* next in chain of held-up int processes */
05126
05127 int p_flags; /* P_SLOT_FREE, SENDING, RECEIVING, etc. */
05128 struct mem_map p_map[NR_SEGS];/* memory map */
05129 pid_t p_pid; /* process id passed in from MM */
05130
05131 clock_t user_time; /* user time in ticks */
05132 clock_t sys_time; /* sys time in ticks */
05133 clock_t child_utime; /* cumulative user time of children */
05134 clock_t child_stime; /* cumulative sys time of children */
05135 clock_t p_alarm; /* time of next alarm in ticks, or 0 */
05136
05137 struct proc *p_callerq; /* head of list of procs wishing to send */
05138 struct proc *p_sendlink; /* link to next proc wishing to send */
05139 message *p_messbuf; /* pointer to message buffer */
05140 int p_getfrom; /* from whom does process want to receive? */
05141 int p_sendto;
05142
05143 struct proc *p_nextready; /* pointer to next ready process */
05144 sigset_t p_pending; /* bit map for pending signals */
05145 unsigned p_pendcount; /* count of pending and unfinished signals */
05146
05147 char p_name[16]; /* name of the process */
05148 };
05149
05150 /* Guard word for task stacks. */
05151 #define STACK_GUARD ((reg_t) (sizeof(reg_t) == 2 ? 0xBEEF : 0xDEADBEEF))
05152
05153 /* Bits for p_flags in proc[]. A process is runnable iff p_flags == 0. */
05154 #define P_SLOT_FREE 001 /* set when slot is not in use */
05155 #define NO_MAP 002 /* keeps unmapped forked child from running */
05156 #define SENDING 004 /* set when process blocked trying to send */
05157 #define RECEIVING 010 /* set when process blocked trying to recv */
05158 #define PENDING 020 /* set when inform() of signal pending */
05159 #define SIG_PENDING 040 /* keeps to-be-signalled proc from running */
05160 #define P_STOP 0100 /* set when process is being traced */
05161
05162 /* Magic process table addresses. */
05163 #define BEG_PROC_ADDR (&proc[0])
05164 #define END_PROC_ADDR (&proc[NR_TASKS + NR_PROCS])
05165 #define END_TASK_ADDR (&proc[NR_TASKS])
05166 #define BEG_SERV_ADDR (&proc[NR_TASKS])
05167 #define BEG_USER_ADDR (&proc[NR_TASKS + LOW_USER])
05168
05169 #define NIL_PROC ((struct proc *) 0)
05170 #define isidlehardware(n) ((n) == IDLE || (n) == HARDWARE)
05171 #define isokprocn(n) ((unsigned) ((n) + NR_TASKS) < NR_PROCS + NR_TASKS)
05172 #define isoksrc_dest(n) (isokprocn(n) || (n) == ANY)
05173 #define isoksusern(n) ((unsigned) (n) < NR_PROCS)
05174 #define isokusern(n) ((unsigned) ((n) - LOW_USER) < NR_PROCS - LOW_USER)
05175 #define isrxhardware(n) ((n) == ANY || (n) == HARDWARE)
05176 #define issysentn(n) ((n) == FS_PROC_NR || (n) == MM_PROC_NR)
05177 #define istaskp(p) ((p) < END_TASK_ADDR && (p) != proc_addr(IDLE))
05178 #define isuserp(p) ((p) >= BEG_USER_ADDR)
05179 #define proc_addr(n) (pproc_addr + NR_TASKS)[(n)]
05180 #define cproc_addr(n) (&(proc + NR_TASKS)[(n)])
05181 #define proc_number(p) ((p)->p_nr)
05182 #define proc_vir2phys(p, vir)
05183 (((phys_bytes)(p)->p_map[D].mem_phys << CLICK_SHIFT)
05184 + (vir_bytes) (vir))
05185
05186 EXTERN struct proc proc[NR_TASKS + NR_PROCS]; /* process table */
05187 EXTERN struct proc *pproc_addr[NR_TASKS + NR_PROCS];
05188 /* ptrs to process table slots; fast because now a process entry can be found
05189 by indexing the pproc_addr array, while accessing an element i requires
05190 a multiplication with sizeof(struct proc) to determine the address */
05191 EXTERN struct proc *bill_ptr; /* ptr to process to bill for clock ticks */
05192 EXTERN struct proc *rdy_head[NQ]; /* pointers to ready list headers */
05193 EXTERN struct proc *rdy_tail[NQ]; /* pointers to ready list tails */
05194
05195 #endif /* PROC_H */
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
src/kernel/protect.h
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
05200 /* Constants for protected mode. */
05201
05202 /* Table sizes. */
05203 #define GDT_SIZE (FIRST_LDT_INDEX + NR_TASKS + NR_PROCS) /* spec. and LDT's */
05204 #define IDT_SIZE (IRQ8_VECTOR + 8) /* only up to the highest vector */
05205 #define LDT_SIZE 2 /* contains CS and DS only */
05206
05207 /* Fixed global descriptors. 1 to 7 are prescribed by the BIOS. */
05208 #define GDT_INDEX 1 /* GDT descriptor */
05209 #define IDT_INDEX 2 /* IDT descriptor */
05210 #define DS_INDEX 3 /* kernel DS */
05211 #define ES_INDEX 4 /* kernel ES (386: flag 4 Gb at startup) */
05212 #define SS_INDEX 5 /* kernel SS (386: monitor SS at startup) */
05213 #define CS_INDEX 6 /* kernel CS */
05214 #define MON_CS_INDEX 7 /* temp for BIOS (386: monitor CS at startup) */
05215 #define TSS_INDEX 8 /* kernel TSS */
05216 #define DS_286_INDEX 9 /* scratch 16-bit source segment */
05217 #define ES_286_INDEX 10 /* scratch 16-bit destination segment */
05218 #define VIDEO_INDEX 11 /* video memory segment */
05219 #define DP_ETH0_INDEX 12 /* Western Digital Etherplus buffer */
05220 #define DP_ETH1_INDEX 13 /* Western Digital Etherplus buffer */
05221 #define FIRST_LDT_INDEX 14 /* rest of descriptors are LDT's */
05222
05223 #define GDT_SELECTOR 0x08 /* (GDT_INDEX * DESC_SIZE) bad for asld */
05224 #define IDT_SELECTOR 0x10 /* (IDT_INDEX * DESC_SIZE) */
05225 #define DS_SELECTOR 0x18 /* (DS_INDEX * DESC_SIZE) */
05226 #define ES_SELECTOR 0x20 /* (ES_INDEX * DESC_SIZE) */
05227 #define FLAT_DS_SELECTOR 0x21 /* less privileged ES */
05228 #define SS_SELECTOR 0x28 /* (SS_INDEX * DESC_SIZE) */
05229 #define CS_SELECTOR 0x30 /* (CS_INDEX * DESC_SIZE) */
05230 #define MON_CS_SELECTOR 0x38 /* (MON_CS_INDEX * DESC_SIZE) */
05231 #define TSS_SELECTOR 0x40 /* (TSS_INDEX * DESC_SIZE) */
05232 #define DS_286_SELECTOR 0x49 /* (DS_286_INDEX * DESC_SIZE + 1) */
05233 #define ES_286_SELECTOR 0x51 /* (ES_286_INDEX * DESC_SIZE + 1) */
05234 #define VIDEO_SELECTOR 0x59 /* (VIDEO_INDEX * DESC_SIZE + 1) */
05235 #define DP_ETH0_SELECTOR 0x61 /* (DP_ETH0_INDEX * DESC_SIZE) */
05236 #define DP_ETH1_SELECTOR 0x69 /* (DP_ETH1_INDEX * DESC_SIZE) */
05237
05238 /* Fixed local descriptors. */
05239 #define CS_LDT_INDEX 0 /* process CS */
05240 #define DS_LDT_INDEX 1 /* process DS=ES=FS=GS=SS */
05241
05242 /* Privileges. */
05243 #define INTR_PRIVILEGE 0 /* kernel and interrupt handlers */
05244 #define TASK_PRIVILEGE 1
05245 #define USER_PRIVILEGE 3
05246
05247 /* 286 hardware constants. */
05248
05249 /* Exception vector numbers. */
05250 #define BOUNDS_VECTOR 5 /* bounds check failed */
05251 #define INVAL_OP_VECTOR 6 /* invalid opcode */
05252 #define COPROC_NOT_VECTOR 7 /* coprocessor not available */
05253 #define DOUBLE_FAULT_VECTOR 8
05254 #define COPROC_SEG_VECTOR 9 /* coprocessor segment overrun */
05255 #define INVAL_TSS_VECTOR 10 /* invalid TSS */
05256 #define SEG_NOT_VECTOR 11 /* segment not present */
05257 #define STACK_FAULT_VECTOR 12 /* stack exception */
05258 #define PROTECTION_VECTOR 13 /* general protection */
05259
05260 /* Selector bits. */
05261 #define TI 0x04 /* table indicator */
05262 #define RPL 0x03 /* requester privilege level */
05263
05264 /* Descriptor structure offsets. */
05265 #define DESC_BASE 2 /* to base_low */
05266 #define DESC_BASE_MIDDLE 4 /* to base_middle */
05267 #define DESC_ACCESS 5 /* to access byte */
05268 #define DESC_SIZE 8 /* sizeof (struct segdesc_s) */
05269
05270 /* Segment sizes. */
05271 #define MAX_286_SEG_SIZE 0x10000L
05272
05273 /* Base and limit sizes and shifts. */
05274 #define BASE_MIDDLE_SHIFT 16 /* shift for base --> base_middle */
05275
05276 /* Access-byte and type-byte bits. */
05277 #define PRESENT 0x80 /* set for descriptor present */
05278 #define DPL 0x60 /* descriptor privilege level mask */
05279 #define DPL_SHIFT 5
05280 #define SEGMENT 0x10 /* set for segment-type descriptors */
05281
05282 /* Access-byte bits. */
05283 #define EXECUTABLE 0x08 /* set for executable segment */
05284 #define CONFORMING 0x04 /* set for conforming segment if executable */
05285 #define EXPAND_DOWN 0x04 /* set for expand-down segment if !executable*/
05286 #define READABLE 0x02 /* set for readable segment if executable */
05287 #define WRITEABLE 0x02 /* set for writeable segment if !executable */
05288 #define TSS_BUSY 0x02 /* set if TSS descriptor is busy */
05289 #define ACCESSED 0x01 /* set if segment accessed */
05290
05291 /* Special descriptor types. */
05292 #define AVL_286_TSS 1 /* available 286 TSS */
05293 #define LDT 2 /* local descriptor table */
05294 #define BUSY_286_TSS 3 /* set transparently to the software */
05295 #define CALL_286_GATE 4 /* not used */
05296 #define TASK_GATE 5 /* only used by debugger */
05297 #define INT_286_GATE 6 /* interrupt gate, used for all vectors */
05298 #define TRAP_286_GATE 7 /* not used */
05299
05300 /* Extra 386 hardware constants. */
05301
05302 /* Exception vector numbers. */
05303 #define PAGE_FAULT_VECTOR 14
05304 #define COPROC_ERR_VECTOR 16 /* coprocessor error */
05305
05306 /* Descriptor structure offsets. */
05307 #define DESC_GRANULARITY 6 /* to granularity byte */
05308 #define DESC_BASE_HIGH 7 /* to base_high */
05309
05310 /* Base and limit sizes and shifts. */
05311 #define BASE_HIGH_SHIFT 24 /* shift for base --> base_high */
05312 #define BYTE_GRAN_MAX 0xFFFFFL /* maximum size for byte granular segment */
05313 #define GRANULARITY_SHIFT 16 /* shift for limit --> granularity */
05314 #define OFFSET_HIGH_SHIFT 16 /* shift for (gate) offset --> offset_high */
05315 #define PAGE_GRAN_SHIFT 12 /* extra shift for page granular limits */
05316
05317 /* Type-byte bits. */
05318 #define DESC_386_BIT 0x08 /* 386 types are obtained by ORing with this */
05319 /* LDT's and TASK_GATE's don't need it */
05320
05321 /* Granularity byte. */
05322 #define GRANULAR 0x80 /* set for 4K granularilty */
05323 #define DEFAULT 0x40 /* set for 32-bit defaults (executable seg) */
05324 #define BIG 0x40 /* set for "BIG" (expand-down seg) */
05325 #define AVL 0x10 /* 0 for available */
05326 #define LIMIT_HIGH 0x0F /* mask for high bits of limit */
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
src/kernel/sconst.h
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
05400 ! Miscellaneous constants used in assembler code.
05401 W = _WORD_SIZE ! Machine word size.
05402
05403 ! Offsets in struct proc. They MUST match proc.h.
05404 P_STACKBASE = 0
05405 #if _WORD_SIZE == 2
05406 ESREG = P_STACKBASE
05407 #else
05408 GSREG = P_STACKBASE
05409 FSREG = GSREG + 2 ! 386 introduces FS and GS segments
05410 ESREG = FSREG + 2
05411 #endif
05412 DSREG = ESREG + 2
05413 DIREG = DSREG + 2
05414 SIREG = DIREG + W
05415 BPREG = SIREG + W
05416 STREG = BPREG + W ! hole for another SP
05417 BXREG = STREG + W
05418 DXREG = BXREG + W
05419 CXREG = DXREG + W
05420 AXREG = CXREG + W
05421 RETADR = AXREG + W ! return address for save() call
05422 PCREG = RETADR + W
05423 CSREG = PCREG + W
05424 PSWREG = CSREG + W
05425 SPREG = PSWREG + W
05426 SSREG = SPREG + W
05427 P_STACKTOP = SSREG + W
05428 P_LDT_SEL = P_STACKTOP
05429 P_LDT = P_LDT_SEL + W
05430
05431 #if _WORD_SIZE == 2
05432 Msize = 12 ! size of a message in 16-bit words
05433 #else
05434 Msize = 9 ! size of a message in 32-bit words
05435 #endif
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
src/kernel/assert.h
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
05500 /*
05501 assert.h
05502 */
05503 #ifndef ASSERT_H
05504 #define ASSERT_H
05505
05506 #if DEBUG
05507
05508 #define INIT_ASSERT static char *assert_file= __FILE__;
05509
05510 void bad_assertion(char *file, int line, char *what);
05511 void bad_compare(char *file, int line, int lhs, char *what, int rhs);
05512
05513 #define assert(x) (!(x) ? bad_assertion(assert_file, __LINE__, #x)
05514 : (void) 0)
05515 #define compare(a,t,b) (!((a) t (b)) ? bad_compare(assert_file, __LINE__,
05516 (a), #a " " #t " " #b, (b)) : (void) 0)
05517 #else /* !DEBUG */
05518
05519 #define INIT_ASSERT /* nothing */
05520
05521 #define assert(x) (void)0
05522 #define compare(a,t,b) (void)0
05523
05524 #endif /* !DEBUG */
05525
05526 #endif /* ASSERT_H */
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
src/kernel/table.c
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
05600 /* The object file of "table.c" contains all the data. In the *.h files,
05601 * declared variables appear with EXTERN in front of them, as in
05602 *
05603 * EXTERN int x;
05604 *
05605 * Normally EXTERN is defined as extern, so when they are included in another
05606 * file, no storage is allocated. If the EXTERN were not present, but just
05607 * say,
05608 *
05609 * int x;
05610 *
05611 * then including this file in several source files would cause 'x' to be
05612 * declared several times. While some linkers accept this, others do not,
05613 * so they are declared extern when included normally. However, it must
05614 * be declared for real somewhere. That is done here, by redefining
05615 * EXTERN as the null string, so the inclusion of all the *.h files in
05616 * table.c actually generates storage for them. All the initialized
05617 * variables are also declared here, since
05618 *
05619 * extern int x = 4;
05620 *
05621 * is not allowed. If such variables are shared, they must also be declared
05622 * in one of the *.h files without the initialization.
05623 */
05624
05625 #define _TABLE
05626
05627 #include "kernel.h"
05628 #include <termios.h>
05629 #include <minix/com.h>
05630 #include "proc.h"
05631 #include "tty.h"
05632
05633 /* The startup routine of each task is given below, from -NR_TASKS upwards.
05634 * The order of the names here MUST agree with the numerical values assigned to
05635 * the tasks in <minix/com.h>.
05636 */
05637 #define SMALL_STACK (128 * sizeof(char *))
05638
05639 #define TTY_STACK (3 * SMALL_STACK)
05640 #define SYN_ALRM_STACK SMALL_STACK
05641
05642 #define DP8390_STACK (SMALL_STACK * ENABLE_NETWORKING)
05643
05644 #if (CHIP == INTEL)
05645 #define IDLE_STACK ((3+3+4) * sizeof(char *)) /* 3 intr, 3 temps, 4 db */
05646 #else
05647 #define IDLE_STACK SMALL_STACK
05648 #endif
05649
05650 #define PRINTER_STACK SMALL_STACK
05651
05652 #if (CHIP == INTEL)
05653 #define WINCH_STACK (2 * SMALL_STACK * ENABLE_WINI)
05654 #else
05655 #define WINCH_STACK (3 * SMALL_STACK * ENABLE_WINI)
05656 #endif
05657
05658 #if (MACHINE == ATARI)
05659 #define SCSI_STACK (3 * SMALL_STACK)
05660 #endif
05661
05662 #if (MACHINE == IBM_PC)
05663 #define SCSI_STACK (2 * SMALL_STACK * ENABLE_SCSI)
05664 #endif
05665
05666 #define CDROM_STACK (4 * SMALL_STACK * ENABLE_CDROM)
05667 #define AUDIO_STACK (4 * SMALL_STACK * ENABLE_AUDIO)
05668 #define MIXER_STACK (4 * SMALL_STACK * ENABLE_AUDIO)
05669
05670 #define FLOP_STACK (3 * SMALL_STACK)
05671 #define MEM_STACK SMALL_STACK
05672 #define CLOCK_STACK SMALL_STACK
05673 #define SYS_STACK SMALL_STACK
05674 #define HARDWARE_STACK 0 /* dummy task, uses kernel stack */
05675
05676
05677 #define TOT_STACK_SPACE (TTY_STACK + DP8390_STACK + SCSI_STACK +
05678 SYN_ALRM_STACK + IDLE_STACK + HARDWARE_STACK + PRINTER_STACK +
05679 WINCH_STACK + FLOP_STACK + MEM_STACK + CLOCK_STACK + SYS_STACK +
05680 CDROM_STACK + AUDIO_STACK + MIXER_STACK)
05681
05682
05683 /* SCSI, CDROM and AUDIO may in the future have different choices like
05684 * WINCHESTER, but for now the choice is fixed.
05685 */
05686 #define scsi_task aha_scsi_task
05687 #define cdrom_task mcd_task
05688 #define audio_task dsp_task
05689
05690
05691 /*
05692 * Some notes about the following table:
05693 * 1) The tty_task should always be first so that other tasks can use printf
05694 * if their initialisation has problems.
05695 * 2) If you add a new kernel task, add it before the printer task.
05696 * 3) The task name is used for the process name (p_name).
05697 */
05698
05699 PUBLIC struct tasktab tasktab[] = {
05700 { tty_task, TTY_STACK, "TTY" },
05701 #if ENABLE_NETWORKING
05702 { dp8390_task, DP8390_STACK, "DP8390" },
05703 #endif
05704 #if ENABLE_CDROM
05705 { cdrom_task, CDROM_STACK, "CDROM" },
05706 #endif
05707 #if ENABLE_AUDIO
05708 { audio_task, AUDIO_STACK, "AUDIO" },
05709 { mixer_task, MIXER_STACK, "MIXER" },
05710 #endif
05711 #if ENABLE_SCSI
05712 { scsi_task, SCSI_STACK, "SCSI" },
05713 #endif
05714 #if ENABLE_WINI
05715 { winchester_task, WINCH_STACK, "WINCH" },
05716 #endif
05717 { syn_alrm_task, SYN_ALRM_STACK, "SYN_AL" },
05718 { idle_task, IDLE_STACK, "IDLE" },
05719 { printer_task, PRINTER_STACK, "PRINTER" },
05720 { floppy_task, FLOP_STACK, "FLOPPY" },
05721 { mem_task, MEM_STACK, "MEMORY" },
05722 { clock_task, CLOCK_STACK, "CLOCK" },
05723 { sys_task, SYS_STACK, "SYS" },
05724 { 0, HARDWARE_STACK, "HARDWAR" },
05725 { 0, 0, "MM" },
05726 { 0, 0, "FS" },
05727 #if ENABLE_NETWORKING
05728 { 0, 0, "INET" },
05729 #endif
05730 { 0, 0, "INIT" },
05731 };
05732
05733 /* Stack space for all the task stacks. (Declared as (char *) to align it.) */
05734 PUBLIC char *t_stack[TOT_STACK_SPACE / sizeof(char *)];
05735
05736 /*
05737 * The number of kernel tasks must be the same as NR_TASKS.
05738 * If NR_TASKS is not correct then you will get the compile error:
05739 * "array size is negative"
05740 */
05741
05742 #define NKT (sizeof tasktab / sizeof (struct tasktab) - (INIT_PROC_NR + 1))
05743
05744 extern int dummy_tasktab_check[NR_TASKS == NKT ? 1 : -1];
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
src/kernel/mpx.s
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
05800 #
05801 ! Chooses between the 8086 and 386 versions of the Minix startup code.
05802
05803 #include <minix/config.h>
05804 #if _WORD_SIZE == 2
05805 #include "mpx88.s"
05806 #else
05807 #include "mpx386.s"
05808 #endif
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
src/kernel/mpx386.s
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
05900 #
05901 ! This file contains the assembler startup code for Minix and the 32-bit
05902 ! interrupt handlers. It cooperates with start.c to set up a good
05903 ! environment for main().
05904
05905 ! This file is part of the lowest layer of the MINIX kernel. The other part
05906 ! is "proc.c". The lowest layer does process switching and message handling.
05907
05908 ! Every transition to the kernel goes through this file. Transitions are
05909 ! caused by sending/receiving messages and by most interrupts. (RS232
05910 ! interrupts may be handled in the file "rs2.s" and then they rarely enter
05911 ! the kernel.)
05912
05913 ! Transitions to the kernel may be nested. The initial entry may be with a
05914 ! system call, exception or hardware interrupt; reentries may only be made
05915 ! by hardware interrupts. The count of reentries is kept in "k_reenter".
05916 ! It is important for deciding whether to switch to the kernel stack and
05917 ! for protecting the message passing code in "proc.c".
05918
05919 ! For the message passing trap, most of the machine state is saved in the
05920 ! proc table. (Some of the registers need not be saved.) Then the stack is
05921 ! switched to "k_stack", and interrupts are reenabled. Finally, the system
05922 ! call handler (in C) is called. When it returns, interrupts are disabled
05923 ! again and the code falls into the restart routine, to finish off held-up
05924 ! interrupts and run the process or task whose pointer is in "proc_ptr".
05925
05926 ! Hardware interrupt handlers do the same, except (1) The entire state must
05927 ! be saved. (2) There are too many handlers to do this inline, so the save
05928 ! routine is called. A few cycles are saved by pushing the address of the
05929 ! appropiate restart routine for a return later. (3) A stack switch is
05930 ! avoided when the stack is already switched. (4) The (master) 8259 interrupt
05931 ! controller is reenabled centrally in save(). (5) Each interrupt handler
05932 ! masks its interrupt line using the 8259 before enabling (other unmasked)
05933 ! interrupts, and unmasks it after servicing the interrupt. This limits the
05934 ! nest level to the number of lines and protects the handler from itself.
05935
05936 ! For communication with the boot monitor at startup time some constant
05937 ! data are compiled into the beginning of the text segment. This facilitates
05938 ! reading the data at the start of the boot process, since only the first
05939 ! sector of the file needs to be read.
05940
05941 ! Some data storage is also allocated at the end of this file. This data
05942 ! will be at the start of the data segment of the kernel and will be read
05943 ! and modified by the boot monitor before the kernel starts.
05944
05945 ! sections
05946
05947 .sect .text
05948 begtext:
05949 .sect .rom
05950 begrom:
05951 .sect .data
05952 begdata:
05953 .sect .bss
05954 begbss:
05955
05956 #include <minix/config.h>
05957 #include <minix/const.h>
05958 #include <minix/com.h>
05959 #include "const.h"
05960 #include "protect.h"
05961 #include "sconst.h"
05962
05963 /* Selected 386 tss offsets. */
05964 #define TSS3_S_SP0 4
05965
05966 ! Exported functions
05967 ! Note: in assembly language the .define statement applied to a function name
05968 ! is loosely equivalent to a prototype in C code -- it makes it possible to
05969 ! link to an entity declared in the assembly code but does not create
05970 ! the entity.
05971
05972 .define _idle_task
05973 .define _restart
05974 .define save
05975
05976 .define _divide_error
05977 .define _single_step_exception
05978 .define _nmi
05979 .define _breakpoint_exception
05980 .define _overflow
05981 .define _bounds_check
05982 .define _inval_opcode
05983 .define _copr_not_available
05984 .define _double_fault
05985 .define _copr_seg_overrun
05986 .define _inval_tss
05987 .define _segment_not_present
05988 .define _stack_exception
05989 .define _general_protection
05990 .define _page_fault
05991 .define _copr_error
05992
05993 .define _hwint00 ! handlers for hardware interrupts
05994 .define _hwint01
05995 .define _hwint02
05996 .define _hwint03
05997 .define _hwint04
05998 .define _hwint05
05999 .define _hwint06
06000 .define _hwint07
06001 .define _hwint08
06002 .define _hwint09
06003 .define _hwint10
06004 .define _hwint11
06005 .define _hwint12
06006 .define _hwint13
06007 .define _hwint14
06008 .define _hwint15
06009
06010 .define _s_call
06011 .define _p_s_call
06012 .define _level0_call
06013
06014 ! Imported functions.
06015
06016 .extern _cstart
06017 .extern _main
06018 .extern _exception
06019 .extern _interrupt
06020 .extern _sys_call
06021 .extern _unhold
06022
06023 ! Exported variables.
06024 ! Note: when used with a variable the .define does not reserve storage,
06025 ! it makes the name externally visible so it may be linked to.
06026
06027 .define begbss
06028 .define begdata
06029 .define _sizes
06030
06031 ! Imported variables.
06032
06033 .extern _gdt
06034 .extern _code_base
06035 .extern _data_base
06036 .extern _held_head
06037 .extern _k_reenter
06038 .extern _pc_at
06039 .extern _proc_ptr
06040 .extern _ps_mca
06041 .extern _tss
06042 .extern _level0_func
06043 .extern _mon_sp
06044 .extern _mon_return
06045 .extern _reboot_code
06046
06047 .sect .text
06048 !*===========================================================================*
06049 !* MINIX *
06050 !*===========================================================================*
06051 MINIX: ! this is the entry point for the MINIX kernel
06052 jmp over_flags ! skip over the next few bytes
06053 .data2 CLICK_SHIFT ! for the monitor: memory granularity
06054 flags:
06055 .data2 0x002D ! boot monitor flags:
06056 ! call in 386 mode, make stack,
06057 ! load high, will return
06058 nop ! extra byte to sync up disassembler
06059 over_flags:
06060
06061 ! Set up a C stack frame on the monitor stack. (The monitor sets cs and ds
06062 ! right. The ss descriptor still references the monitor data segment.)
06063 movzx esp, sp ! monitor stack is a 16 bit stack
06064 push ebp
06065 mov ebp, esp
06066 push esi
06067 push edi
06068 cmp 4(ebp), 0 ! nonzero if return possible
06069 jz noret
06070 inc (_mon_return)
06071 noret: mov (_mon_sp), esp ! save stack pointer for later return
06072
06073 ! Copy the monitor global descriptor table to the address space of kernel and
06074 ! switch over to it. Prot_init() can then update it with immediate effect.
06075
06076 sgdt (_gdt+GDT_SELECTOR) ! get the monitor gdtr
06077 mov esi, (_gdt+GDT_SELECTOR+2) ! absolute address of GDT
06078 mov ebx, _gdt ! address of kernel GDT
06079 mov ecx, 8*8 ! copying eight descriptors
06080 copygdt:
06081 eseg movb al, (esi)
06082 movb (ebx), al
06083 inc esi
06084 inc ebx
06085 loop copygdt
06086 mov eax, (_gdt+DS_SELECTOR+2) ! base of kernel data
06087 and eax, 0x00FFFFFF ! only 24 bits
06088 add eax, _gdt ! eax = vir2phys(gdt)
06089 mov (_gdt+GDT_SELECTOR+2), eax ! set base of GDT
06090 lgdt (_gdt+GDT_SELECTOR) ! switch over to kernel GDT
06091
06092 ! Locate boot parameters, set up kernel segment registers and stack.
06093 mov ebx, 8(ebp) ! boot parameters offset
06094 mov edx, 12(ebp) ! boot parameters length
06095 mov ax, ds ! kernel data
06096 mov es, ax
06097 mov fs, ax
06098 mov gs, ax
06099 mov ss, ax
06100 mov esp, k_stktop ! set sp to point to the top of kernel stack
06101
06102 ! Call C startup code to set up a proper environment to run main().
06103 push edx
06104 push ebx
06105 push SS_SELECTOR
06106 push MON_CS_SELECTOR
06107 push DS_SELECTOR
06108 push CS_SELECTOR
06109 call _cstart ! cstart(cs, ds, mcs, mds, parmoff, parmlen)
06110 add esp, 6*4
06111
06112 ! Reload gdtr, idtr and the segment registers to global descriptor table set
06113 ! up by prot_init().
06114
06115 lgdt (_gdt+GDT_SELECTOR)
06116 lidt (_gdt+IDT_SELECTOR)
06117
06118 jmpf CS_SELECTOR:csinit
06119 csinit:
06120 o16 mov ax, DS_SELECTOR
06121 mov ds, ax
06122 mov es, ax
06123 mov fs, ax
06124 mov gs, ax
06125 mov ss, ax
06126 o16 mov ax, TSS_SELECTOR ! no other TSS is used
06127 ltr ax
06128 push 0 ! set flags to known good state
06129 popf ! esp, clear nested task and int enable
06130
06131 jmp _main ! main()
06132
06133
06134 !*===========================================================================*
06135 !* interrupt handlers *
06136 !* interrupt handlers for 386 32-bit protected mode *
06137 !*===========================================================================*
06138
06139 !*===========================================================================*
06140 !* hwint00 - 07 *
06141 !*===========================================================================*
06142 ! Note this is a macro, it looks like a subroutine.
06143 #define hwint_master(irq)
06144 call save /* save interrupted process state */;
06145 inb INT_CTLMASK ;
06146 orb al, [1<<irq] ;
06147 outb INT_CTLMASK /* disable the irq */;
06148 movb al, ENABLE ;
06149 outb INT_CTL /* reenable master 8259 */;
06150 sti /* enable interrupts */;
06151 push irq /* irq */;
06152 call (_irq_table + 4*irq) /* eax = (*irq_table[irq])(irq) */;
06153 pop ecx ;
06154 cli /* disable interrupts */;
06155 test eax, eax /* need to reenable irq? */;
06156 jz 0f ;
06157 inb INT_CTLMASK ;
06158 andb al, ~[1<<irq] ;
06159 outb INT_CTLMASK /* enable the irq */;
06160 0: ret /* restart (another) process */
06161
06162 ! Each of these entry points is an expansion of the hwint_master macro
06163 .align 16
06164 _hwint00: ! Interrupt routine for irq 0 (the clock).
06165 hwint_master(0)
06166
06167 .align 16
06168 _hwint01: ! Interrupt routine for irq 1 (keyboard)
06169 hwint_master(1)
06170
06171 .align 16
06172 _hwint02: ! Interrupt routine for irq 2 (cascade!)
06173 hwint_master(2)
06174
06175 .align 16
06176 _hwint03: ! Interrupt routine for irq 3 (second serial)
06177 hwint_master(3)
06178
06179 .align 16
06180 _hwint04: ! Interrupt routine for irq 4 (first serial)
06181 hwint_master(4)
06182
06183 .align 16
06184 _hwint05: ! Interrupt routine for irq 5 (XT winchester)
06185 hwint_master(5)
06186
06187 .align 16
06188 _hwint06: ! Interrupt routine for irq 6 (floppy)
06189 hwint_master(6)
06190
06191 .align 16
06192 _hwint07: ! Interrupt routine for irq 7 (printer)
06193 hwint_master(7)
06194
06195 !*===========================================================================*
06196 !* hwint08 - 15 *
06197 !*===========================================================================*
06198 ! Note this is a macro, it looks like a subroutine.
06199 #define hwint_slave(irq)
06200 call save /* save interrupted process state */;
06201 inb INT2_CTLMASK ;
06202 orb al, [1<<[irq-8]] ;
06203 outb INT2_CTLMASK /* disable the irq */;
06204 movb al, ENABLE ;
06205 outb INT_CTL /* reenable master 8259 */;
06206 jmp .+2 /* delay */;
06207 outb INT2_CTL /* reenable slave 8259 */;
06208 sti /* enable interrupts */;
06209 push irq /* irq */;
06210 call (_irq_table + 4*irq) /* eax = (*irq_table[irq])(irq) */;
06211 pop ecx ;
06212 cli /* disable interrupts */;
06213 test eax, eax /* need to reenable irq? */;
06214 jz 0f ;
06215 inb INT2_CTLMASK ;
06216 andb al, ~[1<<[irq-8]] ;
06217 outb INT2_CTLMASK /* enable the irq */;
06218 0: ret /* restart (another) process */
06219
06220 ! Each of these entry points is an expansion of the hwint_slave macro
06221 .align 16
06222 _hwint08: ! Interrupt routine for irq 8 (realtime clock)
06223 hwint_slave(8)
06224
06225 .align 16
06226 _hwint09: ! Interrupt routine for irq 9 (irq 2 redirected)
06227 hwint_slave(9)
06228
06229 .align 16
06230 _hwint10: ! Interrupt routine for irq 10
06231 hwint_slave(10)
06232
06233 .align 16
06234 _hwint11: ! Interrupt routine for irq 11
06235 hwint_slave(11)
06236
06237 .align 16
06238 _hwint12: ! Interrupt routine for irq 12
06239 hwint_slave(12)
06240
06241 .align 16
06242 _hwint13: ! Interrupt routine for irq 13 (FPU exception)
06243 hwint_slave(13)
06244
06245 .align 16
06246 _hwint14: ! Interrupt routine for irq 14 (AT winchester)
06247 hwint_slave(14)
06248
06249 .align 16
06250 _hwint15: ! Interrupt routine for irq 15
06251 hwint_slave(15)
06252
06253 !*===========================================================================*
06254 !* save *
06255 !*===========================================================================*
06256 ! Save for protected mode.
06257 ! This is much simpler than for 8086 mode, because the stack already points
06258 ! into the process table, or has already been switched to the kernel stack.
06259
06260 .align 16
06261 save:
06262 cld ! set direction flag to a known value
06263 pushad ! save "general" registers
06264 o16 push ds ! save ds
06265 o16 push es ! save es
06266 o16 push fs ! save fs
06267 o16 push gs ! save gs
06268 mov dx, ss ! ss is kernel data segment
06269 mov ds, dx ! load rest of kernel segments
06270 mov es, dx ! kernel does not use fs, gs
06271 mov eax, esp ! prepare to return
06272 incb (_k_reenter) ! from -1 if not reentering
06273 jnz set_restart1 ! stack is already kernel stack
06274 mov esp, k_stktop
06275 push _restart ! build return address for int handler
06276 xor ebp, ebp ! for stacktrace
06277 jmp RETADR-P_STACKBASE(eax)
06278
06279 .align 4
06280 set_restart1:
06281 push restart1
06282 jmp RETADR-P_STACKBASE(eax)
06283
06284 !*===========================================================================*
06285 !* _s_call *
06286 !*===========================================================================*
06287 .align 16
06288 _s_call:
06289 _p_s_call:
06290 cld ! set direction flag to a known value
06291 sub esp, 6*4 ! skip RETADR, eax, ecx, edx, ebx, est
06292 push ebp ! stack already points into proc table
06293 push esi
06294 push edi
06295 o16 push ds
06296 o16 push es
06297 o16 push fs
06298 o16 push gs
06299 mov dx, ss
06300 mov ds, dx
06301 mov es, dx
06302 incb (_k_reenter)
06303 mov esi, esp ! assumes P_STACKBASE == 0
06304 mov esp, k_stktop
06305 xor ebp, ebp ! for stacktrace
06306 ! end of inline save
06307 sti ! allow SWITCHER to be interrupted
06308 ! now set up parameters for sys_call()
06309 push ebx ! pointer to user message
06310 push eax ! src/dest
06311 push ecx ! SEND/RECEIVE/BOTH
06312 call _sys_call ! sys_call(function, src_dest, m_ptr)
06313 ! caller is now explicitly in proc_ptr
06314 mov AXREG(esi), eax ! sys_call MUST PRESERVE si
06315 cli ! disable interrupts
06316
06317 ! Fall into code to restart proc/task running.
06318
06319 !*===========================================================================*
06320 !* restart *
06321 !*===========================================================================*
06322 _restart:
06323
06324 ! Flush any held-up interrupts.
06325 ! This reenables interrupts, so the current interrupt handler may reenter.
06326 ! This does not matter, because the current handler is about to exit and no
06327 ! other handlers can reenter since flushing is only done when k_reenter == 0.
06328
06329 cmp (_held_head), 0 ! do fast test to usually avoid function call
06330 jz over_call_unhold
06331 call _unhold ! this is rare so overhead acceptable
06332 over_call_unhold:
06333 mov esp, (_proc_ptr) ! will assume P_STACKBASE == 0
06334 lldt P_LDT_SEL(esp) ! enable segment descriptors for task
06335 lea eax, P_STACKTOP(esp) ! arrange for next interrupt
06336 mov (_tss+TSS3_S_SP0), eax ! to save state in process table
06337 restart1:
06338 decb (_k_reenter)
06339 o16 pop gs
06340 o16 pop fs
06341 o16 pop es
06342 o16 pop ds
06343 popad
06344 add esp, 4 ! skip return adr
06345 iretd ! continue process
06346
06347 !*===========================================================================*
06348 !* exception handlers *
06349 !*===========================================================================*
06350 _divide_error:
06351 push DIVIDE_VECTOR
06352 jmp exception
06353
06354 _single_step_exception:
06355 push DEBUG_VECTOR
06356 jmp exception
06357
06358 _nmi:
06359 push NMI_VECTOR
06360 jmp exception
06361
06362 _breakpoint_exception:
06363 push BREAKPOINT_VECTOR
06364 jmp exception
06365
06366 _overflow:
06367 push OVERFLOW_VECTOR
06368 jmp exception
06369
06370 _bounds_check:
06371 push BOUNDS_VECTOR
06372 jmp exception
06373
06374 _inval_opcode:
06375 push INVAL_OP_VECTOR
06376 jmp exception
06377
06378 _copr_not_available:
06379 push COPROC_NOT_VECTOR
06380 jmp exception
06381
06382 _double_fault:
06383 push DOUBLE_FAULT_VECTOR
06384 jmp errexception
06385
06386 _copr_seg_overrun:
06387 push COPROC_SEG_VECTOR
06388 jmp exception
06389
06390 _inval_tss:
06391 push INVAL_TSS_VECTOR
06392 jmp errexception
06393
06394 _segment_not_present:
06395 push SEG_NOT_VECTOR
06396 jmp errexception
06397
06398 _stack_exception:
06399 push STACK_FAULT_VECTOR
06400 jmp errexception
06401
06402 _general_protection:
06403 push PROTECTION_VECTOR
06404 jmp errexception
06405
06406 _page_fault:
06407 push PAGE_FAULT_VECTOR
06408 jmp errexception
06409
06410 _copr_error:
06411 push COPROC_ERR_VECTOR
06412 jmp exception
06413
06414 !*===========================================================================*
06415 !* exception *
06416 !*===========================================================================*
06417 ! This is called for all exceptions which do not push an error code.
06418
06419 .align 16
06420 exception:
06421 sseg mov (trap_errno), 0 ! clear trap_errno
06422 sseg pop (ex_number)
06423 jmp exception1
06424
06425 !*===========================================================================*
06426 !* errexception *
06427 !*===========================================================================*
06428 ! This is called for all exceptions which push an error code.
06429
06430 .align 16
06431 errexception:
06432 sseg pop (ex_number)
06433 sseg pop (trap_errno)
06434 exception1: ! Common for all exceptions.
06435 push eax ! eax is scratch register
06436 mov eax, 0+4(esp) ! old eip
06437 sseg mov (old_eip), eax
06438 movzx eax, 4+4(esp) ! old cs
06439 sseg mov (old_cs), eax
06440 mov eax, 8+4(esp) ! old eflags
06441 sseg mov (old_eflags), eax
06442 pop eax
06443 call save
06444 push (old_eflags)
06445 push (old_cs)
06446 push (old_eip)
06447 push (trap_errno)
06448 push (ex_number)
06449 call _exception ! (ex_number, trap_errno, old_eip,
06450 ! old_cs, old_eflags)
06451 add esp, 5*4
06452 cli
06453 ret
06454
06455 !*===========================================================================*
06456 !* level0_call *
06457 !*===========================================================================*
06458 _level0_call:
06459 call save
06460 jmp (_level0_func)
06461
06462 !*===========================================================================*
06463 !* idle_task *
06464 !*===========================================================================*
06465 _idle_task: ! executed when there is no work
06466 jmp _idle_task ! a "hlt" before this fails in protected mode
06467
06468 !*===========================================================================*
06469 !* data *
06470 !*===========================================================================*
06471 ! These declarations assure that storage will be allocated at the very
06472 ! beginning of the kernel data section, so the boot monitor can be easily
06473 ! told how to patch these locations. Note that the magic number is put
06474 ! here by the compiler, but will be read by, and then overwritten by,
06475 ! the boot monitor. When the kernel starts the sizes array will be
06476 ! found here, as if it had been initialized by the compiler.
06477
06478 .sect .rom ! Before the string table please
06479 _sizes: ! sizes of kernel, mm, fs filled in by boot
06480 .data2 0x526F ! this must be the first data entry (magic #)
06481 .space 16*2*2-2 ! monitor uses previous word and this space
06482 ! extra space allows for additional servers
06483 .sect .bss
06484 k_stack:
06485 .space K_STACK_BYTES ! kernel stack
06486 k_stktop: ! top of kernel stack
06487 .comm ex_number, 4
06488 .comm trap_errno, 4
06489 .comm old_eip, 4
06490 .comm old_cs, 4
06491 .comm old_eflags, 4
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
src/kernel/start.c
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
06500 /* This file contains the C startup code for Minix on Intel processors.
06501 * It cooperates with mpx.s to set up a good environment for main().
06502 *
06503 * This code runs in real mode for a 16 bit kernel and may have to switch
06504 * to protected mode for a 286.
06505 *
06506 * For a 32 bit kernel this already runs in protected mode, but the selectors
06507 * are still those given by the BIOS with interrupts disabled, so the
06508 * descriptors need to be reloaded and interrupt descriptors made.
06509 */
06510
06511 #include "kernel.h"
06512 #include <stdlib.h>
06513 #include <minix/boot.h>
06514 #include "protect.h"
06515
06516 PRIVATE char k_environ[256]; /* environment strings passed by loader */
06517
06518 FORWARD _PROTOTYPE( int k_atoi, (char *s) );
06519
06520
06521 /*==========================================================================*
06522 * cstart *
06523 *==========================================================================*/
06524 PUBLIC void cstart(cs, ds, mcs, mds, parmoff, parmsize)
06525 U16_t cs, ds; /* Kernel code and data segment */
06526 U16_t mcs, mds; /* Monitor code and data segment */
06527 U16_t parmoff, parmsize; /* boot parameters offset and length */
06528 {
06529 /* Perform system initializations prior to calling main(). */
06530
06531 register char *envp;
06532 phys_bytes mcode_base, mdata_base;
06533 unsigned mon_start;
06534
06535 /* Record where the kernel and the monitor are. */
06536 code_base = seg2phys(cs);
06537 data_base = seg2phys(ds);
06538 mcode_base = seg2phys(mcs);
06539 mdata_base = seg2phys(mds);
06540
06541 /* Initialize protected mode descriptors. */
06542 prot_init();
06543
06544 /* Copy the boot parameters to kernel memory. */
06545 if (parmsize > sizeof k_environ - 2) parmsize = sizeof k_environ - 2;
06546 phys_copy(mdata_base + parmoff, vir2phys(k_environ), (phys_bytes) parmsize);
06547
06548 /* Convert important boot environment variables. */
06549 boot_parameters.bp_rootdev = k_atoi(k_getenv("rootdev"));
06550 boot_parameters.bp_ramimagedev = k_atoi(k_getenv("ramimagedev"));
06551 boot_parameters.bp_ramsize = k_atoi(k_getenv("ramsize"));
06552 boot_parameters.bp_processor = k_atoi(k_getenv("processor"));
06553
06554 /* Type of VDU: */
06555 envp = k_getenv("video");
06556 if (strcmp(envp, "ega") == 0) ega = TRUE;
06557 if (strcmp(envp, "vga") == 0) vga = ega = TRUE;
06558
06559 /* Memory sizes: */
06560 low_memsize = k_atoi(k_getenv("memsize"));
06561 ext_memsize = k_atoi(k_getenv("emssize"));
06562
06563 /* Processor? */
06564 processor = boot_parameters.bp_processor; /* 86, 186, 286, 386, ... */
06565
06566 /* XT, AT or MCA bus? */
06567 envp = k_getenv("bus");
06568 if (envp == NIL_PTR || strcmp(envp, "at") == 0) {
06569 pc_at = TRUE;
06570 } else
06571 if (strcmp(envp, "mca") == 0) {
06572 pc_at = ps_mca = TRUE;
06573 }
06574
06575 /* Decide if mode is protected. */
06576 #if _WORD_SIZE == 2
06577 protected_mode = processor >= 286;
06578 #endif
06579
06580 /* Is there a monitor to return to? If so then keep it safe. */
06581 if (!protected_mode) mon_return = 0;
06582 mon_start = mcode_base / 1024;
06583 if (mon_return && low_memsize > mon_start) low_memsize = mon_start;
06584
06585 /* Return to assembler code to switch to protected mode (if 286), reload
06586 * selectors and call main().
06587 */
06588 }
06591 /*==========================================================================*
06592 * k_atoi *
06593 *==========================================================================*/
06594 PRIVATE int k_atoi(s)
06595 register char *s;
06596 {
06597 /* Convert string to integer. */
06598
06599 return strtol(s, (char **) NULL, 10);
06600 }
06603 /*==========================================================================*
06604 * k_getenv *
06605 *==========================================================================*/
06606 PUBLIC char *k_getenv(name)
06607 char *name;
06608 {
06609 /* Get environment value - kernel version of getenv to avoid setting up the
06610 * usual environment array.
06611 */
06612
06613 register char *namep;
06614 register char *envp;
06615
06616 for (envp = k_environ; *envp != 0;) {
06617 for (namep = name; *namep != 0 && *namep == *envp; namep++, envp++)
06618 ;
06619 if (*namep == '' && *envp == '=') return(envp + 1);
06620 while (*envp++ != 0)
06621 ;
06622 }
06623 return(NIL_PTR);
06624 }
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
src/kernel/main.c
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
06700 /* This file contains the main program of MINIX. The routine main()
06701 * initializes the system and starts the ball rolling by setting up the proc
06702 * table, interrupt vectors, and scheduling each task to run to initialize
06703 * itself.
06704 *
06705 * The entries into this file are:
06706 * main: MINIX main program
06707 * panic: abort MINIX due to a fatal error
06708 */
06709
06710 #include "kernel.h"
06711 #include <signal.h>
06712 #include <unistd.h>
06713 #include <minix/callnr.h>
06714 #include <minix/com.h>
06715 #include "proc.h"
06716
06717
06718 /*===========================================================================*
06719 * main *
06720 *===========================================================================*/
06721 PUBLIC void main()
06722 {
06723 /* Start the ball rolling. */
06724
06725 register struct proc *rp;
06726 register int t;
06727 int sizeindex;
06728 phys_clicks text_base;
06729 vir_clicks text_clicks;
06730 vir_clicks data_clicks;
06731 phys_bytes phys_b;
06732 reg_t ktsb; /* kernel task stack base */
06733 struct memory *memp;
06734 struct tasktab *ttp;
06735
06736 /* Initialize the interrupt controller. */
06737 intr_init(1);
06738
06739 /* Interpret memory sizes. */
06740 mem_init();
06741
06742 /* Clear the process table.
06743 * Set up mappings for proc_addr() and proc_number() macros.
06744 */
06745 for (rp = BEG_PROC_ADDR, t = -NR_TASKS; rp < END_PROC_ADDR; ++rp, ++t) {
06746 rp->p_flags = P_SLOT_FREE;
06747 rp->p_nr = t; /* proc number from ptr */
06748 (pproc_addr + NR_TASKS)[t] = rp; /* proc ptr from number */
06749 }
06750
06751 /* Set up proc table entries for tasks and servers. The stacks of the
06752 * kernel tasks are initialized to an array in data space. The stacks
06753 * of the servers have been added to the data segment by the monitor, so
06754 * the stack pointer is set to the end of the data segment. All the
06755 * processes are in low memory on the 8086. On the 386 only the kernel
06756 * is in low memory, the rest if loaded in extended memory.
06757 */
06758
06759 /* Task stacks. */
06760 ktsb = (reg_t) t_stack;
06761
06762 for (t = -NR_TASKS; t <= LOW_USER; ++t) {
06763 rp = proc_addr(t); /* t's process slot */
06764 ttp = &tasktab[t + NR_TASKS]; /* t's task attributes */
06765 strcpy(rp->p_name, ttp->name);
06766 if (t < 0) {
06767 if (ttp->stksize > 0) {
06768 rp->p_stguard = (reg_t *) ktsb;
06769 *rp->p_stguard = STACK_GUARD;
06770 }
06771 ktsb += ttp->stksize;
06772 rp->p_reg.sp = ktsb;
06773 text_base = code_base >> CLICK_SHIFT;
06774 /* tasks are all in the kernel */
06775 sizeindex = 0; /* and use the full kernel sizes */
06776 memp = &mem[0]; /* remove from this memory chunk */
06777 } else {
06778 sizeindex = 2 * t + 2; /* MM, FS, INIT have their own sizes */
06779 }
06780 rp->p_reg.pc = (reg_t) ttp->initial_pc;
06781 rp->p_reg.psw = istaskp(rp) ? INIT_TASK_PSW : INIT_PSW;
06782
06783 text_clicks = sizes[sizeindex];
06784 data_clicks = sizes[sizeindex + 1];
06785 rp->p_map[T].mem_phys = text_base;
06786 rp->p_map[T].mem_len = text_clicks;
06787 rp->p_map[D].mem_phys = text_base + text_clicks;
06788 rp->p_map[D].mem_len = data_clicks;
06789 rp->p_map[S].mem_phys = text_base + text_clicks + data_clicks;
06790 rp->p_map[S].mem_vir = data_clicks; /* empty - stack is in data */
06791 text_base += text_clicks + data_clicks; /* ready for next, if server */
06792 memp->size -= (text_base - memp->base);
06793 memp->base = text_base; /* memory no longer free */
06794
06795 if (t >= 0) {
06796 /* Initialize the server stack pointer. Take it down one word
06797 * to give crtso.s something to use as "argc".
06798 */
06799 rp->p_reg.sp = (rp->p_map[S].mem_vir +
06800 rp->p_map[S].mem_len) << CLICK_SHIFT;
06801 rp->p_reg.sp -= sizeof(reg_t);
06802 }
06803
06804 #if _WORD_SIZE == 4
06805 /* Servers are loaded in extended memory if in 386 mode. */
06806 if (t < 0) {
06807 memp = &mem[1];
06808 text_base = 0x100000 >> CLICK_SHIFT;
06809 }
06810 #endif
06811 if (!isidlehardware(t)) lock_ready(rp); /* IDLE, HARDWARE neveready */
06812 rp->p_flags = 0;
06813
06814 alloc_segments(rp);
06815 }
06816
06817 proc[NR_TASKS+INIT_PROC_NR].p_pid = 1;/* INIT of course has pid 1 */
06818 bill_ptr = proc_addr(IDLE); /* it has to point somewhere */
06819 lock_pick_proc();
06820
06821 /* Now go to the assembly code to start running the current process. */
06822 restart();
06823 }
06826 /*===========================================================================*
06827 * panic *
06828 *===========================================================================*/
06829 PUBLIC void panic(s,n)
06830 _CONST char *s;
06831 int n;
06832 {
06833 /* The system has run aground of a fatal error. Terminate execution.
06834 * If the panic originated in MM or FS, the string will be empty and the
06835 * file system already syncked. If the panic originates in the kernel, we are
06836 * kind of stuck.
06837 */
06838
06839 if (*s != 0) {
06840 printf("nKernel panic: %s",s);
06841 if (n != NO_NUM) printf(" %d", n);
06842 printf("n");
06843 }
06844 wreboot(RBT_PANIC);
06845 }
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
src/kernel/proc.c
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
06900 /* This file contains essentially all of the process and message handling.
06901 * It has two main entry points from the outside:
06902 *
06903 * sys_call: called when a process or task does SEND, RECEIVE or SENDREC
06904 * interrupt: called by interrupt routines to send a message to task
06905 *
06906 * It also has several minor entry points:
06907 *
06908 * lock_ready: put a process on one of the ready queues so it can be run
06909 * lock_unready: remove a process from the ready queues
06910 * lock_sched: a process has run too long; schedule another one
06911 * lock_mini_send: send a message (used by interrupt signals, etc.)
06912 * lock_pick_proc: pick a process to run (used by system initialization)
06913 * unhold: repeat all held-up interrupts
06914 */
06915
06916 #include "kernel.h"
06917 #include <minix/callnr.h>
06918 #include <minix/com.h>
06919 #include "proc.h"
06920
06921 PRIVATE unsigned char switching; /* nonzero to inhibit interrupt() */
06922
06923 FORWARD _PROTOTYPE( int mini_send, (struct proc *caller_ptr, int dest,
06924 message *m_ptr) );
06925 FORWARD _PROTOTYPE( int mini_rec, (struct proc *caller_ptr, int src,
06926 message *m_ptr) );
06927 FORWARD _PROTOTYPE( void ready, (struct proc *rp) );
06928 FORWARD _PROTOTYPE( void sched, (void) );
06929 FORWARD _PROTOTYPE( void unready, (struct proc *rp) );
06930 FORWARD _PROTOTYPE( void pick_proc, (void) );
06931
06932 #define CopyMess(s,sp,sm,dp,dm)
06933 cp_mess(s, (sp)->p_map[D].mem_phys, (vir_bytes)sm, (dp)->p_map[D].mem_phys, (vir_bytes)dm)
06934
06935 /*===========================================================================*
06936 * interrupt *
06937 *===========================================================================*/
06938 PUBLIC void interrupt(task)
06939 int task; /* number of task to be started */
06940 {
06941 /* An interrupt has occurred. Schedule the task that handles it. */
06942
06943 register struct proc *rp; /* pointer to task's proc entry */
06944
06945 rp = proc_addr(task);
06946
06947 /* If this call would compete with other process-switching functions, put
06948 * it on the 'held' queue to be flushed at the next non-competing restart().
06949 * The competing conditions are:
06950 * (1) k_reenter == (typeof k_reenter) -1:
06951 * Call from the task level, typically from an output interrupt
06952 * routine. An interrupt handler might reenter interrupt(). Rare,
06953 * so not worth special treatment.
06954 * (2) k_reenter > 0:
06955 * Call from a nested interrupt handler. A previous interrupt handler
06956 * might be inside interrupt() or sys_call().
06957 * (3) switching != 0:
06958 * Some process-switching function other than interrupt() is being
06959 * called from the task level, typically sched() from CLOCK. An
06960 * interrupt handler might call interrupt and pass the k_reenter test.
06961 */
06962 if (k_reenter != 0 || switching) {
06963 lock();
06964 if (!rp->p_int_held) {
06965 rp->p_int_held = TRUE;
06966 if (held_head != NIL_PROC)
06967 held_tail->p_nextheld = rp;
06968 else
06969 held_head = rp;
06970 held_tail = rp;
06971 rp->p_nextheld = NIL_PROC;
06972 }
06973 unlock();
06974 return;
06975 }
06976
06977 /* If task is not waiting for an interrupt, record the blockage. */
06978 if ( (rp->p_flags & (RECEIVING | SENDING)) != RECEIVING ||
06979 !isrxhardware(rp->p_getfrom)) {
06980 rp->p_int_blocked = TRUE;
06981 return;
06982 }
06983
06984 /* Destination is waiting for an interrupt.
06985 * Send it a message with source HARDWARE and type HARD_INT.
06986 * No more information can be reliably provided since interrupt messages
06987 * are not queued.
06988 */
06989 rp->p_messbuf->m_source = HARDWARE;
06990 rp->p_messbuf->m_type = HARD_INT;
06991 rp->p_flags &= ~RECEIVING;
06992 rp->p_int_blocked = FALSE;
06993
06994 /* Make rp ready and run it unless a task is already running. This is
06995 * ready(rp) in-line for speed.
06996 */
06997 if (rdy_head[TASK_Q] != NIL_PROC)
06998 rdy_tail[TASK_Q]->p_nextready = rp;
06999 else
07000 proc_ptr = rdy_head[TASK_Q] = rp;
07001 rdy_tail[TASK_Q] = rp;
07002 rp->p_nextready = NIL_PROC;
07003 }
07005 /*===========================================================================*
07006 * sys_call *
07007 *===========================================================================*/
07008 PUBLIC int sys_call(function, src_dest, m_ptr)
07009 int function; /* SEND, RECEIVE, or BOTH */
07010 int src_dest; /* source to receive from or dest to send to */
07011 message *m_ptr; /* pointer to message */
07012 {
07013 /* The only system calls that exist in MINIX are sending and receiving
07014 * messages. These are done by trapping to the kernel with an INT instruction.
07015 * The trap is caught and sys_call() is called to send or receive a message
07016 * (or both). The caller is always given by proc_ptr.
07017 */
07018
07019 register struct proc *rp;
07020 int n;
07021
07022 /* Check for bad system call parameters. */
07023 if (!isoksrc_dest(src_dest)) return(E_BAD_SRC);
07024 rp = proc_ptr;
07025
07026 if (isuserp(rp) && function != BOTH) return(E_NO_PERM);
07027
07028 /* The parameters are ok. Do the call. */
07029 if (function & SEND) {
07030 /* Function = SEND or BOTH. */
07031 n = mini_send(rp, src_dest, m_ptr);
07032 if (function == SEND || n != OK)
07033 return(n); /* done, or SEND failed */
07034 }
07035
07036 /* Function = RECEIVE or BOTH.
07037 * We have checked user calls are BOTH, and trust 'function' otherwise.
07038 */
07039 return(mini_rec(rp, src_dest, m_ptr));
07040 }
07042 /*===========================================================================*
07043 * mini_send *
07044 *===========================================================================*/
07045 PRIVATE int mini_send(caller_ptr, dest, m_ptr)
07046 register struct proc *caller_ptr; /* who is trying to send a message? */
07047 int dest; /* to whom is message being sent? */
07048 message *m_ptr; /* pointer to message buffer */
07049 {
07050 /* Send a message from 'caller_ptr' to 'dest'. If 'dest' is blocked waiting
07051 * for this message, copy the message to it and unblock 'dest'. If 'dest' is
07052 * not waiting at all, or is waiting for another source, queue 'caller_ptr'.
07053 */
07054
07055 register struct proc *dest_ptr, *next_ptr;
07056 vir_bytes vb; /* message buffer pointer as vir_bytes */
07057 vir_clicks vlo, vhi; /* virtual clicks containing message to send */
07058
07059 /* User processes are only allowed to send to FS and MM. Check for this. */
07060 if (isuserp(caller_ptr) && !issysentn(dest)) return(E_BAD_DEST);
07061 dest_ptr = proc_addr(dest); /* pointer to destination's proc entry */
07062 if (dest_ptr->p_flags & P_SLOT_FREE) return(E_BAD_DEST); /* dead dest */
07063
07064 /* This check allows a message to be anywhere in data or stack or gap.
07065 * It will have to be made more elaborate later for machines which
07066 * don't have the gap mapped.
07067 */
07068 vb = (vir_bytes) m_ptr;
07069 vlo = vb >> CLICK_SHIFT; /* vir click for bottom of message */
07070 vhi = (vb + MESS_SIZE - 1) >> CLICK_SHIFT; /* vir click for top of msg */
07071 if (vlo < caller_ptr->p_map[D].mem_vir || vlo > vhi ||
07072 vhi >= caller_ptr->p_map[S].mem_vir + caller_ptr->p_map[S].mem_len)
07073 return(EFAULT);
07074
07075 /* Check for deadlock by 'caller_ptr' and 'dest' sending to each other. */
07076 if (dest_ptr->p_flags & SENDING) {
07077 next_ptr = proc_addr(dest_ptr->p_sendto);
07078 while (TRUE) {
07079 if (next_ptr == caller_ptr) return(ELOCKED);
07080 if (next_ptr->p_flags & SENDING)
07081 next_ptr = proc_addr(next_ptr->p_sendto);
07082 else
07083 break;
07084 }
07085 }
07086
07087 /* Check to see if 'dest' is blocked waiting for this message. */
07088 if ( (dest_ptr->p_flags & (RECEIVING | SENDING)) == RECEIVING &&
07089 (dest_ptr->p_getfrom == ANY ||
07090 dest_ptr->p_getfrom == proc_number(caller_ptr))) {
07091 /* Destination is indeed waiting for this message. */
07092 CopyMess(proc_number(caller_ptr), caller_ptr, m_ptr, dest_ptr,
07093 dest_ptr->p_messbuf);
07094 dest_ptr->p_flags &= ~RECEIVING; /* deblock destination */
07095 if (dest_ptr->p_flags == 0) ready(dest_ptr);
07096 } else {
07097 /* Destination is not waiting. Block and queue caller. */
07098 caller_ptr->p_messbuf = m_ptr;
07099 if (caller_ptr->p_flags == 0) unready(caller_ptr);
07100 caller_ptr->p_flags |= SENDING;
07101 caller_ptr->p_sendto= dest;
07102
07103 /* Process is now blocked. Put in on the destination's queue. */
07104 if ( (next_ptr = dest_ptr->p_callerq) == NIL_PROC)
07105 dest_ptr->p_callerq = caller_ptr;
07106 else {
07107 while (next_ptr->p_sendlink != NIL_PROC)
07108 next_ptr = next_ptr->p_sendlink;
07109 next_ptr->p_sendlink = caller_ptr;
07110 }
07111 caller_ptr->p_sendlink = NIL_PROC;
07112 }
07113 return(OK);
07114 }
07116 /*===========================================================================*
07117 * mini_rec *
07118 *===========================================================================*/
07119 PRIVATE int mini_rec(caller_ptr, src, m_ptr)
07120 register struct proc *caller_ptr; /* process trying to get message */
07121 int src; /* which message source is wanted (or ANY) */
07122 message *m_ptr; /* pointer to message buffer */
07123 {
07124 /* A process or task wants to get a message. If one is already queued,
07125 * acquire it and deblock the sender. If no message from the desired source
07126 * is available, block the caller. No need to check parameters for validity.
07127 * Users calls are always sendrec(), and mini_send() has checked already.
07128 * Calls from the tasks, MM, and FS are trusted.
07129 */
07130
07131 register struct proc *sender_ptr;
07132 register struct proc *previous_ptr;
07133
07134 /* Check to see if a message from desired source is already available. */
07135 if (!(caller_ptr->p_flags & SENDING)) {
07136 /* Check caller queue. */
07137 for (sender_ptr = caller_ptr->p_callerq; sender_ptr != NIL_PROC;
07138 previous_ptr = sender_ptr, sender_ptr = sender_ptr->p_sendlink) {
07139 if (src == ANY || src == proc_number(sender_ptr)) {
07140 /* An acceptable message has been found. */
07141 CopyMess(proc_number(sender_ptr), sender_ptr,
07142 sender_ptr->p_messbuf, caller_ptr, m_ptr);
07143 if (sender_ptr == caller_ptr->p_callerq)
07144 caller_ptr->p_callerq = sender_ptr->p_sendlink;
07145 else
07146 previous_ptr->p_sendlink = sender_ptr->p_sendlink;
07147 if ((sender_ptr->p_flags &= ~SENDING) == 0)
07148 ready(sender_ptr); /* deblock sender */
07149 return(OK);
07150 }
07151 }
07152
07153 /* Check for blocked interrupt. */
07154 if (caller_ptr->p_int_blocked && isrxhardware(src)) {
07155 m_ptr->m_source = HARDWARE;
07156 m_ptr->m_type = HARD_INT;
07157 caller_ptr->p_int_blocked = FALSE;
07158 return(OK);
07159 }
07160 }
07161
07162 /* No suitable message is available. Block the process trying to receive. */
07163 caller_ptr->p_getfrom = src;
07164 caller_ptr->p_messbuf = m_ptr;
07165 if (caller_ptr->p_flags == 0) unready(caller_ptr);
07166 caller_ptr->p_flags |= RECEIVING;
07167
07168 /* If MM has just blocked and there are kernel signals pending, now is the
07169 * time to tell MM about them, since it will be able to accept the message.
07170 */
07171 if (sig_procs > 0 && proc_number(caller_ptr) == MM_PROC_NR && src == ANY)
07172 inform();
07173 return(OK);
07174 }
07176 /*===========================================================================*
07177 * pick_proc *
07178 *===========================================================================*/
07179 PRIVATE void pick_proc()
07180 {
07181 /* Decide who to run now. A new process is selected by setting 'proc_ptr'.
07182 * When a fresh user (or idle) process is selected, record it in 'bill_ptr',
07183 * so the clock task can tell who to bill for system time.
07184 */
07185
07186 register struct proc *rp; /* process to run */
07187
07188 if ( (rp = rdy_head[TASK_Q]) != NIL_PROC) {
07189 proc_ptr = rp;
07190 return;
07191 }
07192 if ( (rp = rdy_head[SERVER_Q]) != NIL_PROC) {
07193 proc_ptr = rp;
07194 return;
07195 }
07196 if ( (rp = rdy_head[USER_Q]) != NIL_PROC) {
07197 proc_ptr = rp;
07198 bill_ptr = rp;
07199 return;
07200 }
07201 /* No one is ready. Run the idle task. The idle task might be made an
07202 * always-ready user task to avoid this special case.
07203 */
07204 bill_ptr = proc_ptr = proc_addr(IDLE);
07205 }
07207 /*===========================================================================*
07208 * ready *
07209 *===========================================================================*/
07210 PRIVATE void ready(rp)
07211 register struct proc *rp; /* this process is now runnable */
07212 {
07213 /* Add 'rp' to the end of one of the queues of runnable processes. Three
07214 * queues are maintained:
07215 * TASK_Q - (highest priority) for runnable tasks
07216 * SERVER_Q - (middle priority) for MM and FS only
07217 * USER_Q - (lowest priority) for user processes
07218 */
07219
07220 if (istaskp(rp)) {
07221 if (rdy_head[TASK_Q] != NIL_PROC)
07222 /* Add to tail of nonempty queue. */
07223 rdy_tail[TASK_Q]->p_nextready = rp;
07224 else {
07225 proc_ptr = /* run fresh task next */
07226 rdy_head[TASK_Q] = rp; /* add to empty queue */
07227 }
07228 rdy_tail[TASK_Q] = rp;
07229 rp->p_nextready = NIL_PROC; /* new entry has no successor */
07230 return;
07231 }
07232 if (!isuserp(rp)) { /* others are similar */
07233 if (rdy_head[SERVER_Q] != NIL_PROC)
07234 rdy_tail[SERVER_Q]->p_nextready = rp;
07235 else
07236 rdy_head[SERVER_Q] = rp;
07237 rdy_tail[SERVER_Q] = rp;
07238 rp->p_nextready = NIL_PROC;
07239 return;
07240 }
07241 if (rdy_head[USER_Q] == NIL_PROC)
07242 rdy_tail[USER_Q] = rp;
07243 rp->p_nextready = rdy_head[USER_Q];
07244 rdy_head[USER_Q] = rp;
07245 /*
07246 if (rdy_head[USER_Q] != NIL_PROC)
07247 rdy_tail[USER_Q]->p_nextready = rp;
07248 else
07249 rdy_head[USER_Q] = rp;
07250 rdy_tail[USER_Q] = rp;
07251 rp->p_nextready = NIL_PROC;
07252 */
07253 }
07255 /*===========================================================================*
07256 * unready *
07257 *===========================================================================*/
07258 PRIVATE void unready(rp)
07259 register struct proc *rp; /* this process is no longer runnable */
07260 {
07261 /* A process has blocked. */
07262
07263 register struct proc *xp;
07264 register struct proc **qtail; /* TASK_Q, SERVER_Q, or USER_Q rdy_tail */
07265
07266 if (istaskp(rp)) {
07267 /* task stack still ok? */
07268 if (*rp->p_stguard != STACK_GUARD)
07269 panic("stack overrun by task", proc_number(rp));
07270
07271 if ( (xp = rdy_head[TASK_Q]) == NIL_PROC) return;
07272 if (xp == rp) {
07273 /* Remove head of queue */
07274 rdy_head[TASK_Q] = xp->p_nextready;
07275 if (rp == proc_ptr) pick_proc();
07276 return;
07277 }
07278 qtail = &rdy_tail[TASK_Q];
07279 }
07280 else if (!isuserp(rp)) {
07281 if ( (xp = rdy_head[SERVER_Q]) == NIL_PROC) return;
07282 if (xp == rp) {
07283 rdy_head[SERVER_Q] = xp->p_nextready;
07284 pick_proc();
07285 return;
07286 }
07287 qtail = &rdy_tail[SERVER_Q];
07288 } else
07289 {
07290 if ( (xp = rdy_head[USER_Q]) == NIL_PROC) return;
07291 if (xp == rp) {
07292 rdy_head[USER_Q] = xp->p_nextready;
07293 pick_proc();
07294 return;
07295 }
07296 qtail = &rdy_tail[USER_Q];
07297 }
07298
07299 /* Search body of queue. A process can be made unready even if it is
07300 * not running by being sent a signal that kills it.
07301 */
07302 while (xp->p_nextready != rp)
07303 if ( (xp = xp->p_nextready) == NIL_PROC) return;
07304 xp->p_nextready = xp->p_nextready->p_nextready;
07305 if (*qtail == rp) *qtail = xp;
07306 }
07308 /*===========================================================================*
07309 * sched *
07310 *===========================================================================*/
07311 PRIVATE void sched()
07312 {
07313 /* The current process has run too long. If another low priority (user)
07314 * process is runnable, put the current process on the end of the user queue,
07315 * possibly promoting another user to head of the queue.
07316 */
07317
07318 if (rdy_head[USER_Q] == NIL_PROC) return;
07319
07320 /* One or more user processes queued. */
07321 rdy_tail[USER_Q]->p_nextready = rdy_head[USER_Q];
07322 rdy_tail[USER_Q] = rdy_head[USER_Q];
07323 rdy_head[USER_Q] = rdy_head[USER_Q]->p_nextready;
07324 rdy_tail[USER_Q]->p_nextready = NIL_PROC;
07325 pick_proc();
07326 }
07328 /*==========================================================================*
07329 * lock_mini_send *
07330 *==========================================================================*/
07331 PUBLIC int lock_mini_send(caller_ptr, dest, m_ptr)
07332 struct proc *caller_ptr; /* who is trying to send a message? */
07333 int dest; /* to whom is message being sent? */
07334 message *m_ptr; /* pointer to message buffer */
07335 {
07336 /* Safe gateway to mini_send() for tasks. */
07337
07338 int result;
07339
07340 switching = TRUE;
07341 result = mini_send(caller_ptr, dest, m_ptr);
07342 switching = FALSE;
07343 return(result);
07344 }
07346 /*==========================================================================*
07347 * lock_pick_proc *
07348 *==========================================================================*/
07349 PUBLIC void lock_pick_proc()
07350 {
07351 /* Safe gateway to pick_proc() for tasks. */
07352
07353 switching = TRUE;
07354 pick_proc();
07355 switching = FALSE;
07356 }
07358 /*==========================================================================*
07359 * lock_ready *
07360 *==========================================================================*/
07361 PUBLIC void lock_ready(rp)
07362 struct proc *rp; /* this process is now runnable */
07363 {
07364 /* Safe gateway to ready() for tasks. */
07365
07366 switching = TRUE;
07367 ready(rp);
07368 switching = FALSE;
07369 }
07372 /*==========================================================================*
07373 * lock_unready *
07374 *==========================================================================*/
07375 PUBLIC void lock_unready(rp)
07376 struct proc *rp; /* this process is no longer runnable */
07377 {
07378 /* Safe gateway to unready() for tasks. */
07379
07380 switching = TRUE;
07381 unready(rp);
07382 switching = FALSE;
07383 }
07385 /*==========================================================================*
07386 * lock_sched *
07387 *==========================================================================*/
07388 PUBLIC void lock_sched()
07389 {
07390 /* Safe gateway to sched() for tasks. */
07391
07392 switching = TRUE;
07393 sched();
07394 switching = FALSE;
07395 }
07397 /*==========================================================================*
07398 * unhold *
07399 *==========================================================================*/
07400 PUBLIC void unhold()
07401 {
07402 /* Flush any held-up interrupts. k_reenter must be 0. held_head must not
07403 * be NIL_PROC. Interrupts must be disabled. They will be enabled but will
07404 * be disabled when this returns.
07405 */
07406
07407 register struct proc *rp; /* current head of held queue */
07408
07409 if (switching) return;
07410 rp = held_head;
07411 do {
07412 if ( (held_head = rp->p_nextheld) == NIL_PROC) held_tail = NIL_PROC;
07413 rp->p_int_held = FALSE;
07414 unlock(); /* reduce latency; held queue may change! */
07415 interrupt(proc_number(rp));
07416 lock(); /* protect the held queue again */
07417 }
07418 while ( (rp = held_head) != NIL_PROC);
07419 }
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
src/kernel/exception.c
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
07500 /* This file contains a simple exception handler. Exceptions in user
07501 * processes are converted to signals. Exceptions in the kernel, MM and
07502 * FS cause a panic.
07503 */
07504
07505 #include "kernel.h"
07506 #include <signal.h>
07507 #include "proc.h"
07508
07509 /*==========================================================================*
07510 * exception *
07511 *==========================================================================*/
07512 PUBLIC void exception(vec_nr)
07513 unsigned vec_nr;
07514 {
07515 /* An exception or unexpected interrupt has occurred. */
07516
07517 struct ex_s {
07518 char *msg;
07519 int signum;
07520 int minprocessor;
07521 };
07522 static struct ex_s ex_data[] = {
07523 "Divide error", SIGFPE, 86,
07524 "Debug exception", SIGTRAP, 86,
07525 "Nonmaskable interrupt", SIGBUS, 86,
07526 "Breakpoint", SIGEMT, 86,
07527 "Overflow", SIGFPE, 86,
07528 "Bounds check", SIGFPE, 186,
07529 "Invalid opcode", SIGILL, 186,
07530 "Coprocessor not available", SIGFPE, 186,
07531 "Double fault", SIGBUS, 286,
07532 "Copressor segment overrun", SIGSEGV, 286,
07533 "Invalid TSS", SIGSEGV, 286,
07534 "Segment not present", SIGSEGV, 286,
07535 "Stack exception", SIGSEGV, 286, /* STACK_FAULT already used */
07536 "General protection", SIGSEGV, 286,
07537 "Page fault", SIGSEGV, 386, /* not close */
07538 NIL_PTR, SIGILL, 0, /* probably software trap */
07539 "Coprocessor error", SIGFPE, 386,
07540 };
07541 register struct ex_s *ep;
07542 struct proc *saved_proc;
07543
07544 saved_proc= proc_ptr; /* Save proc_ptr, because it may be changed by debug
07545 * statements.
07546 */
07547
07548 ep = &ex_data[vec_nr];
07549
07550 if (vec_nr == 2) { /* spurious NMI on some machines */
07551 printf("got spurious NMIn");
07552 return;
07553 }
07554
07555 if (k_reenter == 0 && isuserp(saved_proc)) {
07556 unlock(); /* this is protected like sys_call() */
07557 cause_sig(proc_number(saved_proc), ep->signum);
07558 return;
07559 }
07560
07561 /* This is not supposed to happen. */
07562 if (ep->msg == NIL_PTR || processor < ep->minprocessor)
07563 printf("nIntel-reserved exception %dn", vec_nr);
07564 else
07565 printf("n%sn", ep->msg);
07566 printf("process number %d, pc = 0x%04x:0x%08xn",
07567 proc_number(saved_proc),
07568 (unsigned) saved_proc->p_reg.cs,
07569 (unsigned) saved_proc->p_reg.pc);
07570 panic("exception in system code", NO_NUM);
07571 }
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
src/kernel/i8259.c
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
07600 /* This file contains routines for initializing the 8259 interrupt controller:
07601 * get_irq_handler: address of handler for a given interrupt
07602 * put_irq_handler: register an interrupt handler
07603 * intr_init: initialize the interrupt controller(s)
07604 */
07605
07606 #include "kernel.h"
07607
07608 #define ICW1_AT 0x11 /* edge triggered, cascade, need ICW4 */
07609 #define ICW1_PC 0x13 /* edge triggered, no cascade, need ICW4 */
07610 #define ICW1_PS 0x19 /* level triggered, cascade, need ICW4 */
07611 #define ICW4_AT 0x01 /* not SFNM, not buffered, normal EOI, 8086 */
07612 #define ICW4_PC 0x09 /* not SFNM, buffered, normal EOI, 8086 */
07613
07614 FORWARD _PROTOTYPE( int spurious_irq, (int irq) );
07615
07616 #define set_vec(nr, addr) ((void)0) /* kluge for protected mode */
07617
07618 /*==========================================================================*
07619 * intr_init *
07620 *==========================================================================*/
07621 PUBLIC void intr_init(mine)
07622 int mine;
07623 {
07624 /* Initialize the 8259s, finishing with all interrupts disabled. This is
07625 * only done in protected mode, in real mode we don't touch the 8259s, but
07626 * use the BIOS locations instead. The flag "mine" is set if the 8259s are
07627 * to be programmed for Minix, or to be reset to what the BIOS expects.
07628 */
07629
07630 int i;
07631
07632 lock();
07633 /* The AT and newer PS/2 have two interrupt controllers, one master,
07634 * one slaved at IRQ 2. (We don't have to deal with the PC that
07635 * has just one controller, because it must run in real mode.)
07636 */
07637 out_byte(INT_CTL, ps_mca ? ICW1_PS : ICW1_AT);
07638 out_byte(INT_CTLMASK, mine ? IRQ0_VECTOR : BIOS_IRQ0_VEC);
07639 /* ICW2 for master */
07640 out_byte(INT_CTLMASK, (1 << CASCADE_IRQ)); /* ICW3 tells slaves */
07641 out_byte(INT_CTLMASK, ICW4_AT);
07642 out_byte(INT_CTLMASK, ~(1 << CASCADE_IRQ)); /* IRQ 0-7 mask */
07643 out_byte(INT2_CTL, ps_mca ? ICW1_PS : ICW1_AT);
07644 out_byte(INT2_CTLMASK, mine ? IRQ8_VECTOR : BIOS_IRQ8_VEC);
07645 /* ICW2 for slave */
07646 out_byte(INT2_CTLMASK, CASCADE_IRQ); /* ICW3 is slave nr */
07647 out_byte(INT2_CTLMASK, ICW4_AT);
07648 out_byte(INT2_CTLMASK, ~0); /* IRQ 8-15 mask */
07649
07650 /* Initialize the table of interrupt handlers. */
07651 for (i = 0; i < NR_IRQ_VECTORS; i++) irq_table[i] = spurious_irq;
07652 }
07654 /*=========================================================================*
07655 * spurious_irq *
07656 *=========================================================================*/
07657 PRIVATE int spurious_irq(irq)
07658 int irq;
07659 {
07660 /* Default interrupt handler. It complains a lot. */
07661
07662 if (irq < 0 || irq >= NR_IRQ_VECTORS)
07663 panic("invalid call to spurious_irq", irq);
07664
07665 printf("spurious irq %dn", irq);
07666
07667 return 1; /* Reenable interrupt */
07668 }
07670 /*=========================================================================*
07671 * put_irq_handler *
07672 *=========================================================================*/
07673 PUBLIC void put_irq_handler(irq, handler)
07674 int irq;
07675 irq_handler_t handler;
07676 {
07677 /* Register an interrupt handler. */
07678
07679 if (irq < 0 || irq >= NR_IRQ_VECTORS)
07680 panic("invalid call to put_irq_handler", irq);
07681
07682 if (irq_table[irq] == handler)
07683 return; /* extra initialization */
07684
07685 if (irq_table[irq] != spurious_irq)
07686 panic("attempt to register second irq handler for irq", irq);
07687
07688 disable_irq(irq);
07689 if (!protected_mode) set_vec(BIOS_VECTOR(irq), irq_vec[irq]);
07690 irq_table[irq]= handler;
07691 irq_use |= 1 << irq;
07692 }
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
src/kernel/protect.c
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
07700 /* This file contains code for initialization of protected mode, to initialize
07701 * code and data segment descriptors, and to initialize global descriptors
07702 * for local descriptors in the process table.
07703 */
07704
07705 #include "kernel.h"
07706 #include "proc.h"
07707 #include "protect.h"
07708
07709 #define INT_GATE_TYPE (INT_286_GATE | DESC_386_BIT)
07710 #define TSS_TYPE (AVL_286_TSS | DESC_386_BIT)
07711
07712 struct desctableptr_s {
07713 char limit[sizeof(u16_t)];
07714 char base[sizeof(u32_t)]; /* really u24_t + pad for 286 */
07715 };
07716
07717 struct gatedesc_s {
07718 u16_t offset_low;
07719 u16_t selector;
07720 u8_t pad; /* |000|XXXXX| ig & trpg, |XXXXXXXX| task g */
07721 u8_t p_dpl_type; /* |P|DL|0|TYPE| */
07722 u16_t offset_high;
07723 };
07724
07725 struct tss_s {
07726 reg_t backlink;
07727 reg_t sp0; /* stack pointer to use during interrupt */
07728 reg_t ss0; /* " segment " " " " */
07729 reg_t sp1;
07730 reg_t ss1;
07731 reg_t sp2;
07732 reg_t ss2;
07733 reg_t cr3;
07734 reg_t ip;
07735 reg_t flags;
07736 reg_t ax;
07737 reg_t cx;
07738 reg_t dx;
07739 reg_t bx;
07740 reg_t sp;
07741 reg_t bp;
07742 reg_t si;
07743 reg_t di;
07744 reg_t es;
07745 reg_t cs;
07746 reg_t ss;
07747 reg_t ds;
07748 reg_t fs;
07749 reg_t gs;
07750 reg_t ldt;
07751 u16_t trap;
07752 u16_t iobase;
07753 };
07754
07755 PUBLIC struct segdesc_s gdt[GDT_SIZE];
07756 PRIVATE struct gatedesc_s idt[IDT_SIZE]; /* zero-init so none present */
07757 PUBLIC struct tss_s tss; /* zero init */
07758
07759 FORWARD _PROTOTYPE( void int_gate, (unsigned vec_nr, phys_bytes base,
07760 unsigned dpl_type) );
07761 FORWARD _PROTOTYPE( void sdesc, (struct segdesc_s *segdp, phys_bytes base,
07762 phys_bytes size) );
07763
07764 /*=========================================================================*
07765 * prot_init *
07766 *=========================================================================*/
07767 PUBLIC void prot_init()
07768 {
07769 /* Set up tables for protected mode.
07770 * All GDT slots are allocated at compile time.
07771 */
07772
07773 phys_bytes code_bytes;
07774 phys_bytes data_bytes;
07775 struct gate_table_s *gtp;
07776 struct desctableptr_s *dtp;
07777 unsigned ldt_selector;
07778 register struct proc *rp;
07779
07780 static struct gate_table_s {
07781 _PROTOTYPE( void (*gate), (void) );
07782 unsigned char vec_nr;
07783 unsigned char privilege;
07784 }
07785 gate_table[] = {
07786 divide_error, DIVIDE_VECTOR, INTR_PRIVILEGE,
07787 single_step_exception, DEBUG_VECTOR, INTR_PRIVILEGE,
07788 nmi, NMI_VECTOR, INTR_PRIVILEGE,
07789 breakpoint_exception, BREAKPOINT_VECTOR, USER_PRIVILEGE,
07790 overflow, OVERFLOW_VECTOR, USER_PRIVILEGE,
07791 bounds_check, BOUNDS_VECTOR, INTR_PRIVILEGE,
07792 inval_opcode, INVAL_OP_VECTOR, INTR_PRIVILEGE,
07793 copr_not_available, COPROC_NOT_VECTOR, INTR_PRIVILEGE,
07794 double_fault, DOUBLE_FAULT_VECTOR, INTR_PRIVILEGE,
07795 copr_seg_overrun, COPROC_SEG_VECTOR, INTR_PRIVILEGE,
07796 inval_tss, INVAL_TSS_VECTOR, INTR_PRIVILEGE,
07797 segment_not_present, SEG_NOT_VECTOR, INTR_PRIVILEGE,
07798 stack_exception, STACK_FAULT_VECTOR, INTR_PRIVILEGE,
07799 general_protection, PROTECTION_VECTOR, INTR_PRIVILEGE,
07800 page_fault, PAGE_FAULT_VECTOR, INTR_PRIVILEGE,
07801 copr_error, COPROC_ERR_VECTOR, INTR_PRIVILEGE,
07802 { hwint00, VECTOR( 0), INTR_PRIVILEGE },
07803 { hwint01, VECTOR( 1), INTR_PRIVILEGE },
07804 { hwint02, VECTOR( 2), INTR_PRIVILEGE },
07805 { hwint03, VECTOR( 3), INTR_PRIVILEGE },
07806 { hwint04, VECTOR( 4), INTR_PRIVILEGE },
07807 { hwint05, VECTOR( 5), INTR_PRIVILEGE },
07808 { hwint06, VECTOR( 6), INTR_PRIVILEGE },
07809 { hwint07, VECTOR( 7), INTR_PRIVILEGE },
07810 { hwint08, VECTOR( 8), INTR_PRIVILEGE },
07811 { hwint09, VECTOR( 9), INTR_PRIVILEGE },
07812 { hwint10, VECTOR(10), INTR_PRIVILEGE },
07813 { hwint11, VECTOR(11), INTR_PRIVILEGE },
07814 { hwint12, VECTOR(12), INTR_PRIVILEGE },
07815 { hwint13, VECTOR(13), INTR_PRIVILEGE },
07816 { hwint14, VECTOR(14), INTR_PRIVILEGE },
07817 { hwint15, VECTOR(15), INTR_PRIVILEGE },
07818 };
07819
07820 /* This is called early and can't use tables set up by main(). */
07821 data_bytes = (phys_bytes) sizes[1] << CLICK_SHIFT;
07822 if (sizes[0] == 0)
07823 code_bytes = data_bytes; /* common I&D */
07824 else
07825 code_bytes = (phys_bytes) sizes[0] << CLICK_SHIFT;
07826
07827 /* Build gdt and idt pointers in GDT where the BIOS expects them. */
07828 dtp= (struct desctableptr_s *) &gdt[GDT_INDEX];
07829 * (u16_t *) dtp->limit = (sizeof gdt) - 1;
07830 * (u32_t *) dtp->base = vir2phys(gdt);
07831
07832 dtp= (struct desctableptr_s *) &gdt[IDT_INDEX];
07833 * (u16_t *) dtp->limit = (sizeof idt) - 1;
07834 * (u32_t *) dtp->base = vir2phys(idt);
07835
07836 /* Build segment descriptors for tasks and interrupt handlers. */
07837 init_codeseg(&gdt[CS_INDEX], code_base, code_bytes, INTR_PRIVILEGE);
07838 init_dataseg(&gdt[DS_INDEX], data_base, data_bytes, INTR_PRIVILEGE);
07839 init_dataseg(&gdt[ES_INDEX], 0L, 0L, TASK_PRIVILEGE);
07840
07841 /* Build scratch descriptors for functions in klib88. */
07842 init_dataseg(&gdt[DS_286_INDEX], (phys_bytes) 0,
07843 (phys_bytes) MAX_286_SEG_SIZE, TASK_PRIVILEGE);
07844 init_dataseg(&gdt[ES_286_INDEX], (phys_bytes) 0,
07845 (phys_bytes) MAX_286_SEG_SIZE, TASK_PRIVILEGE);
07846
07847 /* Build local descriptors in GDT for LDT's in process table.
07848 * The LDT's are allocated at compile time in the process table, and
07849 * initialized whenever a process' map is initialized or changed.
07850 */
07851 for (rp = BEG_PROC_ADDR, ldt_selector = FIRST_LDT_INDEX * DESC_SIZE;
07852 rp < END_PROC_ADDR; ++rp, ldt_selector += DESC_SIZE) {
07853 init_dataseg(&gdt[ldt_selector / DESC_SIZE], vir2phys(rp->p_ldt),
07854 (phys_bytes) sizeof rp->p_ldt, INTR_PRIVILEGE);
07855 gdt[ldt_selector / DESC_SIZE].access = PRESENT | LDT;
07856 rp->p_ldt_sel = ldt_selector;
07857 }
07858
07859 /* Build main TSS.
07860 * This is used only to record the stack pointer to be used after an
07861 * interrupt.
07862 * The pointer is set up so that an interrupt automatically saves the
07863 * current process's registers ip:cs:f:sp:ss in the correct slots in the
07864 * process table.
07865 */
07866 tss.ss0 = DS_SELECTOR;
07867 init_dataseg(&gdt[TSS_INDEX], vir2phys(&tss), (phys_bytes) sizeof tss,
07868 INTR_PRIVILEGE);
07869 gdt[TSS_INDEX].access = PRESENT | (INTR_PRIVILEGE << DPL_SHIFT) | TSS_TYPE;
07870 tss.iobase = sizeof tss; /* empty i/o permissions map */
07871
07872 /* Build descriptors for interrupt gates in IDT. */
07873 for (gtp = &gate_table[0];
07874 gtp < &gate_table[sizeof gate_table / sizeof gate_table[0]]; ++gtp) {
07875 int_gate(gtp->vec_nr, (phys_bytes) (vir_bytes) gtp->gate,
07876 PRESENT | INT_GATE_TYPE | (gtp->privilege << DPL_SHIFT));
07877 }
07878 int_gate(SYS_VECTOR, (phys_bytes) (vir_bytes) p_s_call,
07879 PRESENT | (USER_PRIVILEGE << DPL_SHIFT) | INT_GATE_TYPE);
07880 int_gate(LEVEL0_VECTOR, (phys_bytes) (vir_bytes) level0_call,
07881 PRESENT | (TASK_PRIVILEGE << DPL_SHIFT) | INT_GATE_TYPE);
07882 int_gate(SYS386_VECTOR, (phys_bytes) (vir_bytes) s_call,
07883 PRESENT | (USER_PRIVILEGE << DPL_SHIFT) | INT_GATE_TYPE);
07884 }
07886 /*=========================================================================*
07887 * init_codeseg *
07888 *=========================================================================*/
07889 PUBLIC void init_codeseg(segdp, base, size, privilege)
07890 register struct segdesc_s *segdp;
07891 phys_bytes base;
07892 phys_bytes size;