/* This file contains the main program of MINIX as well as its shutdown code. * The routine main() initializes the system and starts the ball rolling by * setting up the process table, interrupt vectors, and scheduling each task * to run to initialize itself. * The routine shutdown() does the opposite and brings down MINIX. * * The entries into this file are: * main: MINIX main program * prepare_shutdown: prepare to take MINIX down */ #include "kernel.h" #include #include #include #include #include #include #include #include "proc.h" #include "debug.h" #include "clock.h" #include "hw_intr.h" #ifdef CONFIG_SMP #include "smp.h" #endif #ifdef CONFIG_WATCHDOG #include "watchdog.h" #endif #include "spinlock.h" /* dummy for linking */ char *** _penviron; /* Prototype declarations for PRIVATE functions. */ FORWARD _PROTOTYPE( void announce, (void)); PUBLIC void bsp_finish_booting(void) { int i; #if SPROFILE sprofiling = 0; /* we're not profiling until instructed to */ #endif /* SPROFILE */ cprof_procs_no = 0; /* init nr of hash table slots used */ cpu_identify(); vm_running = 0; krandom.random_sources = RANDOM_SOURCES; krandom.random_elements = RANDOM_ELEMENTS; /* MINIX is now ready. All boot image processes are on the ready queue. * Return to the assembly code to start running the current process. */ /* it should point somewhere */ get_cpulocal_var(bill_ptr) = get_cpulocal_var_ptr(idle_proc); get_cpulocal_var(proc_ptr) = get_cpulocal_var_ptr(idle_proc); announce(); /* print MINIX startup banner */ /* * we have access to the cpu local run queue, only now schedule the processes. * We ignore the slots for the former kernel tasks */ for (i=0; i < NR_BOOT_PROCS - NR_TASKS; i++) { RTS_UNSET(proc_addr(i), RTS_PROC_STOP); } /* * enable timer interrupts and clock task on the boot CPU */ if (boot_cpu_init_timer(system_hz)) { panic("FATAL : failed to initialize timer interrupts, " "cannot continue without any clock source!"); } fpu_init(); #ifdef CONFIG_WATCHDOG if (watchdog_enabled) { if (arch_watchdog_init()) { printf("WARNING watchdog initialization failed! Disabled\n"); watchdog_enabled = 0; } else BOOT_VERBOSE(printf("Watchdog enabled\n");); } #endif /* Warnings for sanity checks that take time. These warnings are printed * so it's a clear warning no full release should be done with them * enabled. */ #if DEBUG_SCHED_CHECK FIXME("DEBUG_SCHED_CHECK enabled"); #endif #if DEBUG_VMASSERT FIXME("DEBUG_VMASSERT enabled"); #endif #if DEBUG_PROC_CHECK FIXME("PROC check enabled"); #endif DEBUGEXTRA(("cycles_accounting_init()... ")); cycles_accounting_init(); DEBUGEXTRA(("done\n")); #ifdef CONFIG_SMP cpu_set_flag(bsp_cpu_id, CPU_IS_READY); machine.processors_count = ncpus; machine.bsp_id = bsp_cpu_id; #else machine.processors_count = 1; machine.bsp_id = 0; #endif switch_to_user(); NOT_REACHABLE; } /*===========================================================================* * main * *===========================================================================*/ PUBLIC int main(void) { /* Start the ball rolling. */ struct boot_image *ip; /* boot image pointer */ register struct proc *rp; /* process pointer */ register int i, j; int hdrindex; /* index to array of a.out headers */ phys_clicks text_base; vir_clicks text_clicks, data_clicks, st_clicks; reg_t ktsb; /* kernel task stack base */ struct exec e_hdr; /* for a copy of an a.out header */ size_t argsz; /* size of arguments passed to crtso on stack */ BKL_LOCK(); /* Global value to test segment sanity. */ magictest = MAGICTEST; DEBUGEXTRA(("main()\n")); proc_init(); /* Set up proc table entries for processes in boot image. The stacks of the * kernel tasks are initialized to an array in data space. The stacks * of the servers have been added to the data segment by the monitor, so * the stack pointer is set to the end of the data segment. All the * processes are in low memory on the 8086. On the 386 only the kernel * is in low memory, the rest is loaded in extended memory. */ /* Task stacks. */ ktsb = (reg_t) t_stack; for (i=0; i < NR_BOOT_PROCS; ++i) { int schedulable_proc; proc_nr_t proc_nr; int ipc_to_m, kcalls; ip = &image[i]; /* process' attributes */ DEBUGEXTRA(("initializing %s... ", ip->proc_name)); rp = proc_addr(ip->proc_nr); /* get process pointer */ ip->endpoint = rp->p_endpoint; /* ipc endpoint */ make_zero64(rp->p_cpu_time_left); strncpy(rp->p_name, ip->proc_name, P_NAME_LEN); /* set process name */ reset_proc_accounting(rp); /* See if this process is immediately schedulable. * In that case, set its privileges now and allow it to run. * Only kernel tasks and the root system process get to run immediately. * All the other system processes are inhibited from running by the * RTS_NO_PRIV flag. They can only be scheduled once the root system * process has set their privileges. */ proc_nr = proc_nr(rp); schedulable_proc = (iskerneln(proc_nr) || isrootsysn(proc_nr)); if(schedulable_proc) { /* Assign privilege structure. Force a static privilege id. */ (void) get_priv(rp, static_priv_id(proc_nr)); /* Priviliges for kernel tasks. */ if(iskerneln(proc_nr)) { /* Privilege flags. */ priv(rp)->s_flags = (proc_nr == IDLE ? IDL_F : TSK_F); /* Allowed traps. */ priv(rp)->s_trap_mask = (proc_nr == CLOCK || proc_nr == SYSTEM ? CSK_T : TSK_T); ipc_to_m = TSK_M; /* allowed targets */ kcalls = TSK_KC; /* allowed kernel calls */ } /* Priviliges for the root system process. */ else if(isrootsysn(proc_nr)) { priv(rp)->s_flags= RSYS_F; /* privilege flags */ priv(rp)->s_trap_mask= SRV_T; /* allowed traps */ ipc_to_m = SRV_M; /* allowed targets */ kcalls = SRV_KC; /* allowed kernel calls */ priv(rp)->s_sig_mgr = SRV_SM; /* signal manager */ rp->p_priority = SRV_Q; /* priority queue */ rp->p_quantum_size_ms = SRV_QT; /* quantum size */ } /* Priviliges for ordinary process. */ else { NOT_REACHABLE; } /* Fill in target mask. */ fill_sendto_mask(rp, ipc_to_m); /* Fill in kernel call mask. */ for(j = 0; j < SYS_CALL_MASK_SIZE; j++) { priv(rp)->s_k_call_mask[j] = (kcalls == NO_C ? 0 : (~0)); } } else { /* Don't let the process run for now. */ RTS_SET(rp, RTS_NO_PRIV | RTS_NO_QUANTUM); } if (iskerneln(proc_nr)) { /* part of the kernel? */ if (ip->stksize > 0) { /* HARDWARE stack size is 0 */ rp->p_priv->s_stack_guard = (reg_t *) ktsb; *rp->p_priv->s_stack_guard = STACK_GUARD; } ktsb += ip->stksize; /* point to high end of stack */ rp->p_reg.sp = ktsb; /* this task's initial stack ptr */ hdrindex = 0; /* all use the first a.out header */ } else { hdrindex = 1 + i-NR_TASKS; /* system/user processes */ } /* Architecture-specific way to find out aout header of this * boot process. */ arch_get_aout_headers(hdrindex, &e_hdr); /* Convert addresses to clicks and build process memory map */ text_base = e_hdr.a_syms >> CLICK_SHIFT; text_clicks = (vir_clicks) (CLICK_CEIL(e_hdr.a_text) >> CLICK_SHIFT); data_clicks = (vir_clicks) (CLICK_CEIL(e_hdr.a_data + e_hdr.a_bss) >> CLICK_SHIFT); st_clicks = (vir_clicks) (CLICK_CEIL(e_hdr.a_total) >> CLICK_SHIFT); if (!(e_hdr.a_flags & A_SEP)) { data_clicks = (vir_clicks) (CLICK_CEIL(e_hdr.a_text + e_hdr.a_data + e_hdr.a_bss) >> CLICK_SHIFT); text_clicks = 0; /* common I&D */ } rp->p_memmap[T].mem_phys = text_base; rp->p_memmap[T].mem_len = text_clicks; rp->p_memmap[D].mem_phys = text_base + text_clicks; rp->p_memmap[D].mem_len = data_clicks; rp->p_memmap[S].mem_phys = text_base + text_clicks + st_clicks; rp->p_memmap[S].mem_vir = st_clicks; rp->p_memmap[S].mem_len = 0; /* Set initial register values. The processor status word for tasks * is different from that of other processes because tasks can * access I/O; this is not allowed to less-privileged processes */ rp->p_reg.pc = 0; /* we cannot start anything else */ rp->p_reg.psw = (iskerneln(proc_nr)) ? INIT_TASK_PSW : INIT_PSW; /* Initialize the server stack pointer. Take it down three words * to give crtso.s something to use as "argc", "argv" and "envp". */ if (isusern(proc_nr)) { /* user-space process? */ rp->p_reg.sp = (rp->p_memmap[S].mem_vir + rp->p_memmap[S].mem_len) << CLICK_SHIFT; argsz = 3 * sizeof(reg_t); rp->p_reg.sp -= argsz; phys_memset(rp->p_reg.sp - (rp->p_memmap[S].mem_vir << CLICK_SHIFT) + (rp->p_memmap[S].mem_phys << CLICK_SHIFT), 0, argsz); } /* scheduling functions depend on proc_ptr pointing somewhere. */ if(!get_cpulocal_var(proc_ptr)) get_cpulocal_var(proc_ptr) = rp; /* If this process has its own page table, VM will set the * PT up and manage it. VM will signal the kernel when it has * done this; until then, don't let it run. */ if(ip->flags & PROC_FULLVM) rp->p_rts_flags |= RTS_VMINHIBIT; rp->p_rts_flags |= RTS_PROC_STOP; rp->p_rts_flags &= ~RTS_SLOT_FREE; alloc_segments(rp); DEBUGEXTRA(("done\n")); } #define IPCNAME(n) { \ assert((n) >= 0 && (n) <= IPCNO_HIGHEST); \ assert(!ipc_call_names[n]); \ ipc_call_names[n] = #n; \ } IPCNAME(SEND); IPCNAME(RECEIVE); IPCNAME(SENDREC); IPCNAME(NOTIFY); IPCNAME(SENDNB); IPCNAME(SENDA); /* Architecture-dependent initialization. */ DEBUGEXTRA(("arch_init()... ")); arch_init(); DEBUGEXTRA(("done\n")); /* System and processes initialization */ DEBUGEXTRA(("system_init()... ")); system_init(); DEBUGEXTRA(("done\n")); #ifdef CONFIG_SMP if (config_no_apic) { BOOT_VERBOSE(printf("APIC disabled, disables SMP, using legacy PIC\n")); smp_single_cpu_fallback(); } else if (config_no_smp) { BOOT_VERBOSE(printf("SMP disabled, using legacy PIC\n")); smp_single_cpu_fallback(); } else { smp_init(); /* * if smp_init() returns it means that it failed and we try to finish * single CPU booting */ bsp_finish_booting(); } #else /* * if configured for a single CPU, we are already on the kernel stack which we * are going to use everytime we execute kernel code. We finish booting and we * never return here */ bsp_finish_booting(); #endif NOT_REACHABLE; return 1; } /*===========================================================================* * announce * *===========================================================================*/ PRIVATE void announce(void) { /* Display the MINIX startup banner. */ printf("\nMINIX %s.%s. " #ifdef _VCS_REVISION "(" _VCS_REVISION ")\n" #endif "Copyright 2010, Vrije Universiteit, Amsterdam, The Netherlands\n", OS_RELEASE, OS_VERSION); printf("MINIX is open source software, see http://www.minix3.org\n"); } /*===========================================================================* * prepare_shutdown * *===========================================================================*/ PUBLIC void prepare_shutdown(const int how) { /* This function prepares to shutdown MINIX. */ static timer_t shutdown_timer; /* Continue after 1 second, to give processes a chance to get scheduled to * do shutdown work. Set a watchog timer to call shutdown(). The timer * argument passes the shutdown status. */ printf("MINIX will now be shut down ...\n"); tmr_arg(&shutdown_timer)->ta_int = how; set_timer(&shutdown_timer, get_uptime() + system_hz, minix_shutdown); } /*===========================================================================* * shutdown * *===========================================================================*/ PUBLIC void minix_shutdown(timer_t *tp) { /* This function is called from prepare_shutdown or stop_sequence to bring * down MINIX. How to shutdown is in the argument: RBT_HALT (return to the * monitor), RBT_MONITOR (execute given code), RBT_RESET (hard reset). */ #ifdef CONFIG_SMP /* * FIXME * * we will need to stop timers on all cpus if SMP is enabled and put them in * such a state that we can perform the whole boot process once restarted from * monitor again */ if (ncpus > 1) smp_shutdown_aps(); #endif hw_intr_disable_all(); stop_local_timer(); intr_init(INTS_ORIG, 0); arch_shutdown(tp ? tmr_arg(tp)->ta_int : RBT_PANIC); }