681 lines
		
	
	
		
			25 KiB
		
	
	
	
		
			C
		
	
	
		
			Executable File
		
	
	
	
	
			
		
		
	
	
			681 lines
		
	
	
		
			25 KiB
		
	
	
	
		
			C
		
	
	
		
			Executable File
		
	
	
	
	
/* This task handles the interface between the kernel and user-level servers.
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 * System services can be accessed by doing a system call. System calls are 
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 * transformed into request messages, which are handled by this task. By 
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 * convention, a sys_call() is transformed in a SYS_CALL request message that
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 * is handled in a function named do_call(). 
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 *
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 * A private call vector is used to map all system calls to the functions that
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 * handle them. The actual handler functions are contained in separate files
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 * to keep this file clean. The call vector is used in the system task's main
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 * loop to handle all incoming requests.  
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 *
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 * In addition to the main sys_task() entry point, which starts the main loop,
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 * there are several other minor entry points:
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 *   get_priv:		assign privilege structure to user or system process
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 *   set_sendto_bit:	allow a process to send messages to a new target
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 *   unset_sendto_bit:	disallow a process from sending messages to a target
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 *   send_sig:		send a signal directly to a system process
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 *   cause_sig:		take action to cause a signal to occur via PM
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 *   umap_bios:		map virtual address in BIOS_SEG to physical 
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 *   get_randomness:	accumulate randomness in a buffer
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 *   clear_endpoint:	remove a process' ability to send and receive messages
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 *
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 * Changes:
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 *   Aug 04, 2005   check if system call is allowed  (Jorrit N. Herder)
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 *   Jul 20, 2005   send signal to services with message  (Jorrit N. Herder) 
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 *   Jan 15, 2005   new, generalized virtual copy function  (Jorrit N. Herder)
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 *   Oct 10, 2004   dispatch system calls from call vector  (Jorrit N. Herder)
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 *   Sep 30, 2004   source code documentation updated  (Jorrit N. Herder)
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 */
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#include "debug.h"
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#include "kernel.h"
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#include "system.h"
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#include "proc.h"
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#include "vm.h"
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#include <stdlib.h>
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#include <signal.h>
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#include <unistd.h>
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#include <string.h>
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#include <sys/sigcontext.h>
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#include <minix/endpoint.h>
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#include <minix/safecopies.h>
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#include <minix/u64.h>
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#include <sys/vm_i386.h>
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/* Declaration of the call vector that defines the mapping of system calls 
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 * to handler functions. The vector is initialized in sys_init() with map(), 
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 * which makes sure the system call numbers are ok. No space is allocated, 
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 * because the dummy is declared extern. If an illegal call is given, the 
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 * array size will be negative and this won't compile. 
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 */
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PUBLIC int (*call_vec[NR_SYS_CALLS])(message *m_ptr);
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char *callnames[NR_SYS_CALLS];
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#define map(call_nr, handler) \
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    {extern int dummy[NR_SYS_CALLS>(unsigned)(call_nr-KERNEL_CALL) ? 1:-1];} \
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    callnames[(call_nr-KERNEL_CALL)] = #call_nr;	\
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    call_vec[(call_nr-KERNEL_CALL)] = (handler)  
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FORWARD _PROTOTYPE( void initialize, (void));
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FORWARD _PROTOTYPE( void softnotify_check, (void));
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FORWARD _PROTOTYPE( struct proc *vmrestart_check, (message *));
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/*===========================================================================*
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 *				sys_task				     *
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 *===========================================================================*/
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PUBLIC void sys_task()
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{
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/* Main entry point of sys_task.  Get the message and dispatch on type. */
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  static message m;
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  register int result;
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  register struct proc *caller_ptr;
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  int s;
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  int call_nr;
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  int n = 0;
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  /* Initialize the system task. */
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  initialize();
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  while (TRUE) {
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      struct proc *restarting;
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      restarting = vmrestart_check(&m);
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      softnotify_check();
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	if(softnotify)
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		minix_panic("softnotify non-NULL before receive (1)", NO_NUM);
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      if(!restarting) {
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        int r;
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	/* Get work. Block and wait until a request message arrives. */
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	if(softnotify)
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		minix_panic("softnotify non-NULL before receive (2)", NO_NUM);
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	if((r=receive(ANY, &m)) != OK)
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		minix_panic("receive() failed", r);
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	if(m.m_source == SYSTEM)
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		continue;
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	if(softnotify)
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		minix_panic("softnotify non-NULL after receive", NO_NUM);
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      }
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      sys_call_code = (unsigned) m.m_type;
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      call_nr = sys_call_code - KERNEL_CALL;	
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      who_e = m.m_source;
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      okendpt(who_e, &who_p);
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      caller_ptr = proc_addr(who_p);
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	if (caller_ptr->p_endpoint == ipc_stats_target)
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		sys_stats.total= add64u(sys_stats.total, 1);
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      /* See if the caller made a valid request and try to handle it. */
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      if (call_nr < 0 || call_nr >= NR_SYS_CALLS) {	/* check call number */
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#if DEBUG_ENABLE_IPC_WARNINGS
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	  kprintf("SYSTEM: illegal request %d from %d.\n",
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		call_nr,m.m_source);
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#endif
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	if (caller_ptr->p_endpoint == ipc_stats_target)
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		sys_stats.bad_req++;
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	  result = EBADREQUEST;			/* illegal message type */
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      } 
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      else if (!GET_BIT(priv(caller_ptr)->s_k_call_mask, call_nr)) {
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#if DEBUG_ENABLE_IPC_WARNINGS
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	static int curr= 0, limit= 100, extra= 20;
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	if (curr < limit+extra)
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	{
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		kprintf("SYSTEM: request %d from %d denied.\n",
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			call_nr, m.m_source);
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	} else if (curr == limit+extra)
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	{
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		kprintf("sys_task: no debug output for a while\n");
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	}
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	else if (curr == 2*limit-1)
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		limit *= 2;
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	curr++;
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#endif
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	if (caller_ptr->p_endpoint == ipc_stats_target)
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		sys_stats.not_allowed++;
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	  result = ECALLDENIED;			/* illegal message type */
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      }
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      else {
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          result = (*call_vec[call_nr])(&m); /* handle the system call */
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      }
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      if(result == VMSUSPEND) {
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	/* Special case: message has to be saved for handling
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	 * until VM tells us it's allowed. VM has been notified
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	 * and we must wait for its reply to restart the call.
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	 */
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	memcpy(&caller_ptr->p_vmrequest.saved.reqmsg, &m, sizeof(m));
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	caller_ptr->p_vmrequest.type = VMSTYPE_SYS_MESSAGE;
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      } else if (result != EDONTREPLY) {
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	/* Send a reply, unless inhibited by a handler function.
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	 * Use the kernel function lock_send() to prevent a system
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	 * call trap.
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	 */
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		if(restarting)
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			RTS_LOCK_UNSET(restarting, VMREQUEST);
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		m.m_type = result;		/* report status of call */
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		if(WILLRECEIVE(caller_ptr, SYSTEM)) {
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		  if (OK != (s=lock_send(m.m_source, &m))) {
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			kprintf("SYSTEM, reply to %d failed: %d\n",
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			m.m_source, s);
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		  }
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		} else {
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			kprintf("SYSTEM: not replying to %d; not ready\n", 
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				caller_ptr->p_endpoint);
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		}
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	}
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  }
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}
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/*===========================================================================*
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 *				initialize				     *
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 *===========================================================================*/
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PRIVATE void initialize(void)
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{
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  register struct priv *sp;
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  int i;
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  /* Initialize IRQ handler hooks. Mark all hooks available. */
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  for (i=0; i<NR_IRQ_HOOKS; i++) {
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      irq_hooks[i].proc_nr_e = NONE;
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  }
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  /* Initialize all alarm timers for all processes. */
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  for (sp=BEG_PRIV_ADDR; sp < END_PRIV_ADDR; sp++) {
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    tmr_inittimer(&(sp->s_alarm_timer));
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  }
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  /* Initialize the call vector to a safe default handler. Some system calls 
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   * may be disabled or nonexistant. Then explicitely map known calls to their
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   * handler functions. This is done with a macro that gives a compile error
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   * if an illegal call number is used. The ordering is not important here.
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   */
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  for (i=0; i<NR_SYS_CALLS; i++) {
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      call_vec[i] = do_unused;
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      callnames[i] = "unused";
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  }
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  /* Process management. */
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  map(SYS_FORK, do_fork); 		/* a process forked a new process */
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  map(SYS_EXEC, do_exec);		/* update process after execute */
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  map(SYS_EXIT, do_exit);		/* clean up after process exit */
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  map(SYS_NICE, do_nice);		/* set scheduling priority */
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  map(SYS_PRIVCTL, do_privctl);		/* system privileges control */
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  map(SYS_TRACE, do_trace);		/* request a trace operation */
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  map(SYS_SETGRANT, do_setgrant);	/* get/set own parameters */
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  /* Signal handling. */
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  map(SYS_KILL, do_kill); 		/* cause a process to be signaled */
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  map(SYS_GETKSIG, do_getksig);		/* PM checks for pending signals */
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  map(SYS_ENDKSIG, do_endksig);		/* PM finished processing signal */
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  map(SYS_SIGSEND, do_sigsend);		/* start POSIX-style signal */
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  map(SYS_SIGRETURN, do_sigreturn);	/* return from POSIX-style signal */
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  /* Device I/O. */
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  map(SYS_IRQCTL, do_irqctl);  		/* interrupt control operations */ 
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  map(SYS_DEVIO, do_devio);   		/* inb, inw, inl, outb, outw, outl */ 
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  map(SYS_VDEVIO, do_vdevio);  		/* vector with devio requests */ 
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  /* Memory management. */
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  map(SYS_NEWMAP, do_newmap);		/* set up a process memory map */
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  map(SYS_SEGCTL, do_segctl);		/* add segment and get selector */
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  map(SYS_MEMSET, do_memset);		/* write char to memory area */
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  map(SYS_VM_SETBUF, do_vm_setbuf); 	/* PM passes buffer for page tables */
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  map(SYS_VMCTL, do_vmctl);		/* various VM process settings */
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  /* Copying. */
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  map(SYS_UMAP, do_umap);		/* map virtual to physical address */
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  map(SYS_VIRCOPY, do_vircopy); 	/* use pure virtual addressing */
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  map(SYS_PHYSCOPY, do_copy);	 	/* use physical addressing */
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  map(SYS_VIRVCOPY, do_virvcopy);	/* vector with copy requests */
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  map(SYS_PHYSVCOPY, do_vcopy);		/* vector with copy requests */
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  map(SYS_SAFECOPYFROM, do_safecopy);	/* copy with pre-granted permission */
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  map(SYS_SAFECOPYTO, do_safecopy);	/* copy with pre-granted permission */
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  map(SYS_VSAFECOPY, do_vsafecopy);	/* vectored safecopy */
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  /* Clock functionality. */
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  map(SYS_TIMES, do_times);		/* get uptime and process times */
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  map(SYS_SETALARM, do_setalarm);	/* schedule a synchronous alarm */
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  map(SYS_STIME, do_stime);		/* set the boottime */
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  map(SYS_VTIMER, do_vtimer);		/* set or retrieve a virtual timer */
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  /* System control. */
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  map(SYS_ABORT, do_abort);		/* abort MINIX */
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  map(SYS_GETINFO, do_getinfo); 	/* request system information */ 
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  map(SYS_SYSCTL, do_sysctl); 		/* misc system manipulation */ 
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  /* Profiling. */
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  map(SYS_SPROF, do_sprofile);         /* start/stop statistical profiling */
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  map(SYS_CPROF, do_cprofile);         /* get/reset call profiling data */
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  map(SYS_PROFBUF, do_profbuf);        /* announce locations to kernel */
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  /* i386-specific. */
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#if _MINIX_CHIP == _CHIP_INTEL
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  map(SYS_INT86, do_int86);  		/* real-mode BIOS calls */ 
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  map(SYS_READBIOS, do_readbios);	/* read from BIOS locations */
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  map(SYS_IOPENABLE, do_iopenable); 	/* Enable I/O */
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  map(SYS_SDEVIO, do_sdevio);		/* phys_insb, _insw, _outsb, _outsw */
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  map(SYS_MAPDMA, do_mapdma);		
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#endif
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}
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/*===========================================================================*
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 *				get_priv				     *
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 *===========================================================================*/
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PUBLIC int get_priv(rc, proc_type)
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register struct proc *rc;		/* new (child) process pointer */
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int proc_type;				/* system or user process flag */
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{
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/* Get a privilege structure. All user processes share the same privilege 
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 * structure. System processes get their own privilege structure. 
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 */
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  register struct priv *sp;			/* privilege structure */
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  if (proc_type == SYS_PROC) {			/* find a new slot */
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      for (sp = BEG_PRIV_ADDR; sp < END_PRIV_ADDR; ++sp) 
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          if (sp->s_proc_nr == NONE && sp->s_id != USER_PRIV_ID) break;	
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      if (sp >= END_PRIV_ADDR) return(ENOSPC);
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      rc->p_priv = sp;				/* assign new slot */
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      rc->p_priv->s_proc_nr = proc_nr(rc);	/* set association */
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      rc->p_priv->s_flags = SYS_PROC;		/* mark as privileged */
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      /* Clear some fields */
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      sp->s_asyntab= -1;	
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      sp->s_asynsize= 0;
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  } else {
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      rc->p_priv = &priv[USER_PRIV_ID];		/* use shared slot */
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      rc->p_priv->s_proc_nr = INIT_PROC_NR;	/* set association */
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      /* s_flags of this shared structure are to be once at system startup. */
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  }
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  return(OK);
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}
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/*===========================================================================*
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 *				set_sendto_bit				     *
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 *===========================================================================*/
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PUBLIC void set_sendto_bit(struct proc *rp, int id)
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{
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/* Allow a process to send messages to the process(es) associated with the
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 * system privilege structure with the given ID. 
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 */
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  struct proc *rrp;			/* receiver process */
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  /* Disallow the process from sending to a system privilege structure with no
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   * associated process, and disallow the process from sending to itself.
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   */
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  if (id_to_nr(id) == NONE || priv_id(rp) == id)
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	return;
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  set_sys_bit(priv(rp)->s_ipc_to, id);
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  /* The process that this process can now send to, must be able to reply.
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   * Therefore, its send mask should be updated as well.
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   */
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  rrp = proc_addr(id_to_nr(id));
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  if (!iskernelp(rrp))
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	set_sys_bit(priv(rrp)->s_ipc_to, priv_id(rp));
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}
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/*===========================================================================*
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 *				unset_sendto_bit			     *
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 *===========================================================================*/
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PUBLIC void unset_sendto_bit(struct proc *rp, int id)
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{
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/* Prevent a process from sending to another process. Retain the send mask
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 * symmetry by also unsetting the bit for the other direction.
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 */
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  unset_sys_bit(priv(rp)->s_ipc_to, id);
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  unset_sys_bit(priv_addr(id)->s_ipc_to, priv_id(rp));
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}
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/*===========================================================================*
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 *				send_sig				     *
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 *===========================================================================*/
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PUBLIC void send_sig(int proc_nr, int sig_nr)
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{
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/* Notify a system process about a signal. This is straightforward. Simply
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 * set the signal that is to be delivered in the pending signals map and 
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 * send a notification with source SYSTEM.
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 */ 
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  register struct proc *rp;
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  static int n;
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  if(!isokprocn(proc_nr) || isemptyn(proc_nr))
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	minix_panic("send_sig to empty process", proc_nr);
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  rp = proc_addr(proc_nr);
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  sigaddset(&priv(rp)->s_sig_pending, sig_nr);
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  soft_notify(rp->p_endpoint); 
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}
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/*===========================================================================*
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 *				cause_sig				     *
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 *===========================================================================*/
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PUBLIC void cause_sig(proc_nr, sig_nr)
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int proc_nr;			/* process to be signalled */
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int sig_nr;			/* signal to be sent, 1 to _NSIG */
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{
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/* A system process wants to send a signal to a process.  Examples are:
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 *  - HARDWARE wanting to cause a SIGSEGV after a CPU exception
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 *  - TTY wanting to cause SIGINT upon getting a DEL
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 *  - FS wanting to cause SIGPIPE for a broken pipe 
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 * Signals are handled by sending a message to PM.  This function handles the 
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 * signals and makes sure the PM gets them by sending a notification. The 
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 * process being signaled is blocked while PM has not finished all signals 
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 * for it. 
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 * Race conditions between calls to this function and the system calls that
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 * process pending kernel signals cannot exist. Signal related functions are
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 * only called when a user process causes a CPU exception and from the kernel 
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 * process level, which runs to completion.
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 */
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  register struct proc *rp;
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  if (proc_nr == PM_PROC_NR)
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	minix_panic("cause_sig: PM gets signal", NO_NUM);
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  /* Check if the signal is already pending. Process it otherwise. */
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  rp = proc_addr(proc_nr);
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  if (! sigismember(&rp->p_pending, sig_nr)) {
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      sigaddset(&rp->p_pending, sig_nr);
 | 
						|
      if (! (RTS_ISSET(rp, SIGNALED))) {		/* other pending */
 | 
						|
	  RTS_LOCK_SET(rp, SIGNALED | SIG_PENDING);
 | 
						|
          send_sig(PM_PROC_NR, SIGKSIG);
 | 
						|
      }
 | 
						|
  }
 | 
						|
}
 | 
						|
 | 
						|
#if _MINIX_CHIP == _CHIP_INTEL
 | 
						|
 | 
						|
/*===========================================================================*
 | 
						|
 *				umap_bios				     *
 | 
						|
 *===========================================================================*/
 | 
						|
PUBLIC phys_bytes umap_bios(vir_addr, bytes)
 | 
						|
vir_bytes vir_addr;		/* virtual address in BIOS segment */
 | 
						|
vir_bytes bytes;		/* # of bytes to be copied */
 | 
						|
{
 | 
						|
/* Calculate the physical memory address at the BIOS. Note: currently, BIOS
 | 
						|
 * address zero (the first BIOS interrupt vector) is not considered as an 
 | 
						|
 * error here, but since the physical address will be zero as well, the 
 | 
						|
 * calling function will think an error occurred. This is not a problem,
 | 
						|
 * since no one uses the first BIOS interrupt vector.  
 | 
						|
 */
 | 
						|
 | 
						|
  /* Check all acceptable ranges. */
 | 
						|
  if (vir_addr >= BIOS_MEM_BEGIN && vir_addr + bytes <= BIOS_MEM_END)
 | 
						|
  	return (phys_bytes) vir_addr;
 | 
						|
  else if (vir_addr >= BASE_MEM_TOP && vir_addr + bytes <= UPPER_MEM_END)
 | 
						|
  	return (phys_bytes) vir_addr;
 | 
						|
 | 
						|
  kprintf("Warning, error in umap_bios, virtual address 0x%x\n", vir_addr);
 | 
						|
  return 0;
 | 
						|
}
 | 
						|
#endif
 | 
						|
 | 
						|
/*===========================================================================*
 | 
						|
 *                              umap_grant                                   *
 | 
						|
 *===========================================================================*/
 | 
						|
PUBLIC phys_bytes umap_grant(rp, grant, bytes)
 | 
						|
struct proc *rp;                /* pointer to proc table entry for process */
 | 
						|
cp_grant_id_t grant;            /* grant no. */
 | 
						|
vir_bytes bytes;                /* size */
 | 
						|
{
 | 
						|
        int proc_nr;
 | 
						|
        vir_bytes offset, ret;
 | 
						|
        endpoint_t granter;
 | 
						|
 | 
						|
        /* See if the grant in that process is sensible, and 
 | 
						|
         * find out the virtual address and (optionally) new
 | 
						|
         * process for that address.
 | 
						|
         *
 | 
						|
         * Then convert that process to a slot number.
 | 
						|
         */
 | 
						|
        if(verify_grant(rp->p_endpoint, ANY, grant, bytes, 0, 0,
 | 
						|
                &offset, &granter) != OK) {
 | 
						|
		kprintf("SYSTEM: umap_grant: verify_grant failed\n");
 | 
						|
                return 0;
 | 
						|
        }
 | 
						|
 | 
						|
        if(!isokendpt(granter, &proc_nr)) {
 | 
						|
		kprintf("SYSTEM: umap_grant: isokendpt failed\n");
 | 
						|
                return 0;
 | 
						|
        }
 | 
						|
 
 | 
						|
        /* Do the mapping from virtual to physical. */
 | 
						|
        ret = umap_virtual(proc_addr(proc_nr), D, offset, bytes);
 | 
						|
	if(!ret) {
 | 
						|
		kprintf("SYSTEM:umap_grant:umap_virtual failed; grant %s:%d -> %s: vir 0x%lx\n",
 | 
						|
			rp->p_name, grant, 
 | 
						|
			proc_addr(proc_nr)->p_name, offset);
 | 
						|
	}
 | 
						|
	return ret;
 | 
						|
}
 | 
						|
 | 
						|
/*===========================================================================*
 | 
						|
 *			         clear_endpoint				     *
 | 
						|
 *===========================================================================*/
 | 
						|
PUBLIC void clear_endpoint(rc)
 | 
						|
register struct proc *rc;		/* slot of process to clean up */
 | 
						|
{
 | 
						|
  register struct proc *rp;		/* iterate over process table */
 | 
						|
  register struct proc **xpp;		/* iterate over caller queue */
 | 
						|
  struct proc *np;
 | 
						|
 | 
						|
  if(isemptyp(rc)) minix_panic("clear_proc: empty process", rc->p_endpoint);
 | 
						|
 | 
						|
  if(rc->p_endpoint == PM_PROC_NR || rc->p_endpoint == VFS_PROC_NR) {
 | 
						|
	/* This test is great for debugging system processes dying,
 | 
						|
	 * but as this happens normally on reboot, not good permanent code.
 | 
						|
	 */
 | 
						|
	kprintf("process %s / %d died; stack: ", rc->p_name, rc->p_endpoint);
 | 
						|
	proc_stacktrace(rc);
 | 
						|
	kprintf("kernel trace: ");
 | 
						|
	util_stacktrace();
 | 
						|
	minix_panic("clear_proc: system process died", rc->p_endpoint);
 | 
						|
  }
 | 
						|
 | 
						|
  /* Make sure that the exiting process is no longer scheduled. */
 | 
						|
  RTS_LOCK_SET(rc, NO_ENDPOINT);
 | 
						|
  if (priv(rc)->s_flags & SYS_PROC)
 | 
						|
  {
 | 
						|
	if (priv(rc)->s_asynsize) {
 | 
						|
		kprintf("clear_endpoint: clearing s_asynsize of %s / %d\n",
 | 
						|
			rc->p_name, rc->p_endpoint);
 | 
						|
		proc_stacktrace(rc);
 | 
						|
	}
 | 
						|
	priv(rc)->s_asynsize= 0;
 | 
						|
  }
 | 
						|
 | 
						|
  /* If the process happens to be queued trying to send a
 | 
						|
   * message, then it must be removed from the message queues.
 | 
						|
   */
 | 
						|
  if (RTS_ISSET(rc, SENDING)) {
 | 
						|
      int target_proc;
 | 
						|
 | 
						|
      okendpt(rc->p_sendto_e, &target_proc);
 | 
						|
      xpp = &proc_addr(target_proc)->p_caller_q; /* destination's queue */
 | 
						|
      while (*xpp != NIL_PROC) {		/* check entire queue */
 | 
						|
          if (*xpp == rc) {			/* process is on the queue */
 | 
						|
              *xpp = (*xpp)->p_q_link;		/* replace by next process */
 | 
						|
#if DEBUG_ENABLE_IPC_WARNINGS
 | 
						|
	      kprintf("endpoint %d / %s removed from queue at %d\n",
 | 
						|
	          rc->p_endpoint, rc->p_name, rc->p_sendto_e);
 | 
						|
#endif
 | 
						|
              break;				/* can only be queued once */
 | 
						|
          }
 | 
						|
          xpp = &(*xpp)->p_q_link;		/* proceed to next queued */
 | 
						|
      }
 | 
						|
      rc->p_rts_flags &= ~SENDING;
 | 
						|
  }
 | 
						|
  rc->p_rts_flags &= ~RECEIVING;
 | 
						|
 | 
						|
  /* Likewise, if another process was sending or receive a message to or from 
 | 
						|
   * the exiting process, it must be alerted that process no longer is alive.
 | 
						|
   * Check all processes. 
 | 
						|
   */
 | 
						|
  for (rp = BEG_PROC_ADDR; rp < END_PROC_ADDR; rp++) {
 | 
						|
      if(isemptyp(rp))
 | 
						|
	continue;
 | 
						|
 | 
						|
      /* Unset pending notification bits. */
 | 
						|
      unset_sys_bit(priv(rp)->s_notify_pending, priv(rc)->s_id);
 | 
						|
 | 
						|
      /* Check if process is receiving from exiting process. */
 | 
						|
      if (RTS_ISSET(rp, RECEIVING) && rp->p_getfrom_e == rc->p_endpoint) {
 | 
						|
          rp->p_reg.retreg = ESRCDIED;		/* report source died */
 | 
						|
	  RTS_LOCK_UNSET(rp, RECEIVING);	/* no longer receiving */
 | 
						|
#if DEBUG_ENABLE_IPC_WARNINGS
 | 
						|
	  kprintf("endpoint %d / %s receiving from dead src ep %d / %s\n",
 | 
						|
		rp->p_endpoint, rp->p_name, rc->p_endpoint, rc->p_name);
 | 
						|
#endif
 | 
						|
      } 
 | 
						|
      if (RTS_ISSET(rp, SENDING) &&
 | 
						|
	  rp->p_sendto_e == rc->p_endpoint) {
 | 
						|
          rp->p_reg.retreg = EDSTDIED;		/* report destination died */
 | 
						|
	  RTS_LOCK_UNSET(rp, SENDING);
 | 
						|
#if DEBUG_ENABLE_IPC_WARNINGS
 | 
						|
	  kprintf("endpoint %d / %s send to dying dst ep %d (%s)\n",
 | 
						|
		rp->p_endpoint, rp->p_name, rc->p_endpoint, rc->p_name);
 | 
						|
#endif
 | 
						|
      } 
 | 
						|
  }
 | 
						|
 | 
						|
  /* No pending soft notifies. */
 | 
						|
  for(np = softnotify; np; np = np->next_soft_notify) {
 | 
						|
    if(np == rc) {
 | 
						|
	minix_panic("dying proc was on next_soft_notify", np->p_endpoint);
 | 
						|
    }
 | 
						|
  }
 | 
						|
}
 | 
						|
 | 
						|
/*===========================================================================*
 | 
						|
 *                              umap_verify_grant                            *
 | 
						|
 *===========================================================================*/
 | 
						|
PUBLIC phys_bytes umap_verify_grant(rp, grantee, grant, offset, bytes, access)
 | 
						|
struct proc *rp;                /* pointer to proc table entry for process */
 | 
						|
endpoint_t grantee;             /* who wants to do this */ 
 | 
						|
cp_grant_id_t grant;            /* grant no. */
 | 
						|
vir_bytes offset;               /* offset into grant */
 | 
						|
vir_bytes bytes;                /* size */
 | 
						|
int access;                     /* does grantee want to CPF_READ or _WRITE? */
 | 
						|
{  
 | 
						|
        int proc_nr;
 | 
						|
        vir_bytes v_offset;
 | 
						|
        endpoint_t granter;
 | 
						|
    
 | 
						|
        /* See if the grant in that process is sensible, and
 | 
						|
         * find out the virtual address and (optionally) new
 | 
						|
         * process for that address. 
 | 
						|
         *
 | 
						|
         * Then convert that process to a slot number.
 | 
						|
         */
 | 
						|
        if(verify_grant(rp->p_endpoint, grantee, grant, bytes, access, offset, 
 | 
						|
                &v_offset, &granter) != OK
 | 
						|
           || !isokendpt(granter, &proc_nr)) {
 | 
						|
                return 0;
 | 
						|
        }
 | 
						|
  
 | 
						|
        /* Do the mapping from virtual to physical. */
 | 
						|
        return umap_virtual(proc_addr(proc_nr), D, v_offset, bytes);
 | 
						|
} 
 | 
						|
 | 
						|
/*===========================================================================*
 | 
						|
 *                              softnotify_check                            *
 | 
						|
 *===========================================================================*/
 | 
						|
PRIVATE void softnotify_check(void)
 | 
						|
{  
 | 
						|
	struct proc *np, *nextnp;
 | 
						|
 | 
						|
	if(!softnotify) 
 | 
						|
		return;
 | 
						|
 | 
						|
	for(np = softnotify; np; np = nextnp) {
 | 
						|
		if(!np->p_softnotified)
 | 
						|
			minix_panic("softnotify but no p_softnotified", NO_NUM);
 | 
						|
		lock_notify(SYSTEM, np->p_endpoint);
 | 
						|
		nextnp = np->next_soft_notify;
 | 
						|
		np->next_soft_notify = NULL;
 | 
						|
		np->p_softnotified = 0;
 | 
						|
	}
 | 
						|
 | 
						|
	softnotify = NULL;
 | 
						|
}
 | 
						|
 | 
						|
/*===========================================================================*
 | 
						|
 *                              vmrestart_check                            *
 | 
						|
 *===========================================================================*/
 | 
						|
PRIVATE struct proc *vmrestart_check(message *m)
 | 
						|
{
 | 
						|
	int type, r;
 | 
						|
	struct proc *restarting;
 | 
						|
 | 
						|
      /* Anyone waiting to be vm-restarted? */
 | 
						|
 | 
						|
	if(!(restarting = vmrestart))
 | 
						|
		return NULL;
 | 
						|
 | 
						|
	if(restarting->p_rts_flags & SLOT_FREE)
 | 
						|
	   minix_panic("SYSTEM: VMREQUEST set for empty process", NO_NUM);
 | 
						|
 | 
						|
	type = restarting->p_vmrequest.type;
 | 
						|
	restarting->p_vmrequest.type = VMSTYPE_SYS_NONE;
 | 
						|
	vmrestart = restarting->p_vmrequest.nextrestart;
 | 
						|
 | 
						|
	if(!RTS_ISSET(restarting, VMREQUEST))
 | 
						|
	   minix_panic("SYSTEM: VMREQUEST not set for process on vmrestart queue",
 | 
						|
		restarting->p_endpoint);
 | 
						|
 | 
						|
	switch(type) {
 | 
						|
		case VMSTYPE_SYS_MESSAGE:
 | 
						|
			memcpy(m, &restarting->p_vmrequest.saved.reqmsg, sizeof(*m));
 | 
						|
			if(m->m_source != restarting->p_endpoint)
 | 
						|
			   minix_panic("SYSTEM: vmrestart source doesn't match",
 | 
						|
				NO_NUM);
 | 
						|
			/* Original caller could've disappeared in the meantime. */
 | 
						|
		        if(!isokendpt(m->m_source, &who_p)) {
 | 
						|
				kprintf("SYSTEM: ignoring call %d from dead %d\n",
 | 
						|
					m->m_type, m->m_source);
 | 
						|
				return NULL;
 | 
						|
			}
 | 
						|
			{ int i;
 | 
						|
				i = m->m_type - KERNEL_CALL;
 | 
						|
				if(i >= 0 && i < NR_SYS_CALLS) {
 | 
						|
#if 0
 | 
						|
					kprintf("SYSTEM: restart %s from %d\n",
 | 
						|
					callnames[i], m->m_source);
 | 
						|
#endif
 | 
						|
				} else {
 | 
						|
	   				minix_panic("call number out of range", i);
 | 
						|
				}
 | 
						|
			}
 | 
						|
			return restarting;
 | 
						|
		case VMSTYPE_SYS_CALL:
 | 
						|
			kprintf("SYSTEM: restart sys_call\n");
 | 
						|
			/* Restarting a kernel trap. */
 | 
						|
			sys_call_restart(restarting);
 | 
						|
 | 
						|
			/* Handled; restart system loop. */
 | 
						|
			return NULL;
 | 
						|
		case VMSTYPE_MSGCOPY:
 | 
						|
			/* Do delayed message copy. */
 | 
						|
			if((r=data_copy(SYSTEM,
 | 
						|
				(vir_bytes) &restarting->p_vmrequest.saved.msgcopy.msgbuf,
 | 
						|
				restarting->p_vmrequest.saved.msgcopy.dst->p_endpoint,
 | 
						|
				(vir_bytes) restarting->p_vmrequest.saved.msgcopy.dst_v,
 | 
						|
				sizeof(message))) != OK) {
 | 
						|
	   			minix_panic("SYSTEM: delayed msgcopy failed", r);
 | 
						|
			}
 | 
						|
			RTS_LOCK_UNSET(restarting, VMREQUEST);
 | 
						|
 | 
						|
			/* Handled; restart system loop. */
 | 
						|
			return NULL;
 | 
						|
		default:
 | 
						|
	   		minix_panic("strange restart type", type);
 | 
						|
	}
 | 
						|
	minix_panic("fell out of switch", NO_NUM);
 | 
						|
}
 |