minix/servers/pm/mproc.h
David van Moolenbroek b423d7b477 Merge of David's ptrace branch. Summary:
o Support for ptrace T_ATTACH/T_DETACH and T_SYSCALL
o PM signal handling logic should now work properly, even with debuggers
  being present
o Asynchronous PM/VFS protocol, full IPC support for senda(), and
  AMF_NOREPLY senda() flag

DETAILS

Process stop and delay call handling of PM:
o Added sys_runctl() kernel call with sys_stop() and sys_resume()
  aliases, for PM to stop and resume a process
o Added exception for sending/syscall-traced processes to sys_runctl(),
  and matching SIGKREADY pseudo-signal to PM
o Fixed PM signal logic to deal with requests from a process after
  stopping it (so-called "delay calls"), using the SIGKREADY facility
o Fixed various PM panics due to race conditions with delay calls versus
  VFS calls
o Removed special PRIO_STOP priority value
o Added SYS_LOCK RTS kernel flag, to stop an individual process from
  running while modifying its process structure

Signal and debugger handling in PM:
o Fixed debugger signals being dropped if a second signal arrives when
  the debugger has not retrieved the first one
o Fixed debugger signals being sent to the debugger more than once
o Fixed debugger signals unpausing process in VFS; removed PM_UNPAUSE_TR
  protocol message
o Detached debugger signals from general signal logic and from being
  blocked on VFS calls, meaning that even VFS can now be traced
o Fixed debugger being unable to receive more than one pending signal in
  one process stop
o Fixed signal delivery being delayed needlessly when multiple signals
  are pending
o Fixed wait test for tracer, which was returning for children that were
  not waited for
o Removed second parallel pending call from PM to VFS for any process
o Fixed process becoming runnable between exec() and debugger trap
o Added support for notifying the debugger before the parent when a
  debugged child exits
o Fixed debugger death causing child to remain stopped forever
o Fixed consistently incorrect use of _NSIG

Extensions to ptrace():
o Added T_ATTACH and T_DETACH ptrace request, to attach and detach a
  debugger to and from a process
o Added T_SYSCALL ptrace request, to trace system calls
o Added T_SETOPT ptrace request, to set trace options
o Added TO_TRACEFORK trace option, to attach automatically to children
  of a traced process
o Added TO_ALTEXEC trace option, to send SIGSTOP instead of SIGTRAP upon
  a successful exec() of the tracee
o Extended T_GETUSER ptrace support to allow retrieving a process's priv
  structure
o Removed T_STOP ptrace request again, as it does not help implementing
  debuggers properly
o Added MINIX3-specific ptrace test (test42)
o Added proper manual page for ptrace(2)

Asynchronous PM/VFS interface:
o Fixed asynchronous messages not being checked when receive() is called
  with an endpoint other than ANY
o Added AMF_NOREPLY senda() flag, preventing such messages from
  satisfying the receive part of a sendrec()
o Added asynsend3() that takes optional flags; asynsend() is now a
  #define passing in 0 as third parameter
o Made PM/VFS protocol asynchronous; reintroduced tell_fs()
o Made PM_BASE request/reply number range unique
o Hacked in a horrible temporary workaround into RS to deal with newly
  revealed RS-PM-VFS race condition triangle until VFS is asynchronous

System signal handling:
o Fixed shutdown logic of device drivers; removed old SIGKSTOP signal
o Removed is-superuser check from PM's do_procstat() (aka getsigset())
o Added sigset macros to allow system processes to deal with the full
  signal set, rather than just the POSIX subset

Miscellaneous PM fixes:
o Split do_getset into do_get and do_set, merging common code and making
  structure clearer
o Fixed setpriority() being able to put to sleep processes using an
  invalid parameter, or revive zombie processes
o Made find_proc() global; removed obsolete proc_from_pid()
o Cleanup here and there

Also included:
o Fixed false-positive boot order kernel warning
o Removed last traces of old NOTIFY_FROM code

THINGS OF POSSIBLE INTEREST

o It should now be possible to run PM at any priority, even lower than
  user processes
o No assumptions are made about communication speed between PM and VFS,
  although communication must be FIFO
o A debugger will now receive incoming debuggee signals at kill time
  only; the process may not yet be fully stopped
o A first step has been made towards making the SYSTEM task preemptible
2009-09-30 09:57:22 +00:00

78 lines
3.7 KiB
C

/* This table has one slot per process. It contains all the process management
* information for each process. Among other things, it defines the text, data
* and stack segments, uids and gids, and various flags. The kernel and file
* systems have tables that are also indexed by process, with the contents
* of corresponding slots referring to the same process in all three.
*/
#include <timers.h>
#include <signal.h>
/* Needs to be included here, for 'ps' etc */
#include "const.h"
EXTERN struct mproc {
char mp_exitstatus; /* storage for status when process exits */
char mp_sigstatus; /* storage for signal # for killed procs */
pid_t mp_pid; /* process id */
endpoint_t mp_endpoint; /* kernel endpoint id */
pid_t mp_procgrp; /* pid of process group (used for signals) */
pid_t mp_wpid; /* pid this process is waiting for */
int mp_parent; /* index of parent process */
int mp_tracer; /* index of tracer process, or NO_TRACER */
/* Child user and system times. Accounting done on child exit. */
clock_t mp_child_utime; /* cumulative user time of children */
clock_t mp_child_stime; /* cumulative sys time of children */
/* Real and effective uids and gids. */
uid_t mp_realuid; /* process' real uid */
uid_t mp_effuid; /* process' effective uid */
gid_t mp_realgid; /* process' real gid */
gid_t mp_effgid; /* process' effective gid */
/* Signal handling information. */
sigset_t mp_ignore; /* 1 means ignore the signal, 0 means don't */
sigset_t mp_catch; /* 1 means catch the signal, 0 means don't */
sigset_t mp_sig2mess; /* 1 means transform into notify message */
sigset_t mp_sigmask; /* signals to be blocked */
sigset_t mp_sigmask2; /* saved copy of mp_sigmask */
sigset_t mp_sigpending; /* pending signals to be handled */
sigset_t mp_sigtrace; /* signals to hand to tracer first */
struct sigaction mp_sigact[_NSIG]; /* as in sigaction(2) */
vir_bytes mp_sigreturn; /* address of C library __sigreturn function */
struct timer mp_timer; /* watchdog timer for alarm(2), setitimer(2) */
clock_t mp_interval[NR_ITIMERS]; /* setitimer(2) repetition intervals */
unsigned mp_flags; /* flag bits */
unsigned mp_trace_flags; /* trace options */
vir_bytes mp_procargs; /* ptr to proc's initial stack arguments */
message mp_reply; /* reply message to be sent to one */
/* Scheduling priority. */
signed int mp_nice; /* nice is PRIO_MIN..PRIO_MAX, standard 0. */
char mp_name[PROC_NAME_LEN]; /* process name */
} mproc[NR_PROCS];
/* Flag values */
#define IN_USE 0x00001 /* set when 'mproc' slot in use */
#define WAITING 0x00002 /* set by WAIT system call */
#define ZOMBIE 0x00004 /* waiting for parent to issue WAIT call */
#define PAUSED 0x00008 /* set by PAUSE system call */
#define ALARM_ON 0x00010 /* set when SIGALRM timer started */
#define EXITING 0x00020 /* set by EXIT, process is now exiting */
#define TOLD_PARENT 0x00040 /* parent wait() completed, ZOMBIE off */
#define STOPPED 0x00080 /* set if process stopped for tracing */
#define SIGSUSPENDED 0x00100 /* set by SIGSUSPEND system call */
#define REPLY 0x00200 /* set if a reply message is pending */
#define FS_CALL 0x00400 /* set if waiting for FS (normal calls) */
#define PM_SIG_PENDING 0x00800 /* process got a signal while waiting for FS */
#define UNPAUSED 0x01000 /* process is not in a blocking call */
#define PRIV_PROC 0x02000 /* system process, special privileges */
#define PARTIAL_EXEC 0x04000 /* process got a new map but no content */
#define TRACE_EXIT 0x08000 /* tracer is forcing this process to exit */
#define TRACE_ZOMBIE 0x10000 /* waiting for tracer to issue WAIT call */
#define DELAY_CALL 0x20000 /* waiting for call before sending signal */
#define NIL_MPROC ((struct mproc *) 0)