minix/kernel/proc.h

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#ifndef PROC_H
#define PROC_H
/* Here is the declaration of the process table. It contains all process
* data, including registers, flags, scheduling priority, memory map,
* accounting, message passing (IPC) information, and so on.
*
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* Many assembly code routines reference fields in it. The offsets to these
* fields are defined in the assembler include file sconst.h. When changing
* struct proc, be sure to change sconst.h to match.
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*/
#include <minix/com.h>
#include "const.h"
#include "priv.h"
Mostly bugfixes of bugs triggered by the test set. bugfixes: SYSTEM: . removed rc->p_priv->s_flags = 0; for the priv struct shared by all user processes in get_priv(). this should only be done once. doing a SYS_PRIV_USER in sys_privctl() caused the flags of all user processes to be reset, so they were no longer PREEMPTIBLE. this happened when RS executed a policy script. (this broke test1 in the test set) VFS/MFS: . chown can change the mode of a file, and chmod arguments are only part of the full file mode so the full filemode is slightly magic. changed these calls so that the final modes are returned to VFS, so that the vnode can be kept up-to-date. (this broke test11 in the test set) MFS: . lookup() checked for sizeof(string) instead of sizeof(user_path), truncating long path names (caught by test 23) . truncate functions neglected to update ctime (this broke test16) VFS: . corner case of an empty filename lookup caused fields of a request not to be filled in in the lookup functions, not making it clear that the lookup had failed, causing messages to garbage processes, causing strange failures. (caught by test 30) . trust v_size in vnode when doing reads or writes on non-special files, truncating i/o where necessary; this is necessary for pipes, as MFS can't tell when a pipe has been truncated without it being told explicitly each time. when the last reader/writer on a pipe closes, tell FS about the new size using truncate_vn(). (this broke test 25, among others) . permission check for chdir() had disappeared; added a forbidden() call (caught by test 23) new code, shouldn't change anything: . introduced RTS_SET, RTS_UNSET, and RTS_ISSET macro's, and their LOCK variants. These macros set and clear the p_rts_flags field, causing a lot of duplicated logic like old_flags = rp->p_rts_flags; /* save value of the flags */ rp->p_rts_flags &= ~NO_PRIV; if (old_flags != 0 && rp->p_rts_flags == 0) lock_enqueue(rp); to change into the simpler RTS_LOCK_UNSET(rp, NO_PRIV); so the macros take care of calling dequeue() and enqueue() (or lock_*()), as the case may be). This makes the code a bit more readable and a bit less fragile. . removed return code from do_clocktick in CLOCK as it currently never replies . removed some debug code from VFS . fixed grant debug message in device.c preemptive checks, tests, changes: . added return code checks of receive() to SYSTEM and CLOCK . O_TRUNC should never arrive at MFS (added sanity check and removed O_TRUNC code) . user_path declared with PATH_MAX+1 to let it be null-terminated . checks in MFS to see if strings passed by VFS are null-terminated IS: . static irq name table thrown out
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struct proc {
struct stackframe_s p_reg; /* process' registers saved in stack frame */
Split of architecture-dependent and -independent functions for i386, mainly in the kernel and headers. This split based on work by Ingmar Alting <iaalting@cs.vu.nl> done for his Minix PowerPC architecture port. . kernel does not program the interrupt controller directly, do any other architecture-dependent operations, or contain assembly any more, but uses architecture-dependent functions in arch/$(ARCH)/. . architecture-dependent constants and types defined in arch/$(ARCH)/include. . <ibm/portio.h> moved to <minix/portio.h>, as they have become, for now, architecture-independent functions. . int86, sdevio, readbios, and iopenable are now i386-specific kernel calls and live in arch/i386/do_* now. . i386 arch now supports even less 86 code; e.g. mpx86.s and klib86.s have gone, and 'machine.protected' is gone (and always taken to be 1 in i386). If 86 support is to return, it should be a new architecture. . prototypes for the architecture-dependent functions defined in kernel/arch/$(ARCH)/*.c but used in kernel/ are in kernel/proto.h . /etc/make.conf included in makefiles and shell scripts that need to know the building architecture; it defines ARCH=<arch>, currently only i386. . some basic per-architecture build support outside of the kernel (lib) . in clock.c, only dequeue a process if it was ready . fixes for new include files files deleted: . mpx/klib.s - only for choosing between mpx/klib86 and -386 . klib86.s - only for 86 i386-specific files files moved (or arch-dependent stuff moved) to arch/i386/: . mpx386.s (entry point) . klib386.s . sconst.h . exception.c . protect.c . protect.h . i8269.c
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struct segframe p_seg; /* segment descriptors */
proc_nr_t p_nr; /* number of this process (for fast access) */
struct priv *p_priv; /* system privileges structure */
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short p_rts_flags; /* process is runnable only if zero */
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short p_misc_flags; /* flags that do not suspend the process */
char p_priority; /* current scheduling priority */
char p_max_priority; /* maximum scheduling priority */
char p_ticks_left; /* number of scheduling ticks left */
char p_quantum_size; /* quantum size in ticks */
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struct mem_map p_memmap[NR_LOCAL_SEGS]; /* memory map (T, D, S) */
clock_t p_user_time; /* user time in ticks */
clock_t p_sys_time; /* sys time in ticks */
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struct proc *p_nextready; /* pointer to next ready process */
struct proc *p_caller_q; /* head of list of procs wishing to send */
struct proc *p_q_link; /* link to next proc wishing to send */
message *p_messbuf; /* pointer to passed message buffer */
'proc number' is process slot, 'endpoint' are generation-aware process instance numbers, encoded and decoded using macros in <minix/endpoint.h>. proc number -> endpoint migration . proc_nr in the interrupt hook is now an endpoint, proc_nr_e. . m_source for messages and notifies is now an endpoint, instead of proc number. . isokendpt() converts an endpoint to a process number, returns success (but fails if the process number is out of range, the process slot is not a living process, or the given endpoint number does not match the endpoint number in the process slot, indicating an old process). . okendpt() is the same as isokendpt(), but panic()s if the conversion fails. This is mainly used for decoding message.m_source endpoints, and other endpoint numbers in kernel data structures, which should always be correct. . if DEBUG_ENABLE_IPC_WARNINGS is enabled, isokendpt() and okendpt() get passed the __FILE__ and __LINE__ of the calling lines, and print messages about what is wrong with the endpoint number (out of range proc, empty proc, or inconsistent endpoint number), with the caller, making finding where the conversion failed easy without having to include code for every call to print where things went wrong. Sometimes this is harmless (wrong arg to a kernel call), sometimes it's a fatal internal inconsistency (bogus m_source). . some process table fields have been appended an _e to indicate it's become and endpoint. . process endpoint is stored in p_endpoint, without generation number. it turns out the kernel never needs the generation number, except when fork()ing, so it's decoded then. . kernel calls all take endpoints as arguments, not proc numbers. the one exception is sys_fork(), which needs to know in which slot to put the child.
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int p_getfrom_e; /* from whom does process want to receive? */
int p_sendto_e; /* to whom does process want to send? */
sigset_t p_pending; /* bit map for pending kernel signals */
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char p_name[P_NAME_LEN]; /* name of the process, including \0 */
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endpoint_t p_endpoint; /* endpoint number, generation-aware */
'proc number' is process slot, 'endpoint' are generation-aware process instance numbers, encoded and decoded using macros in <minix/endpoint.h>. proc number -> endpoint migration . proc_nr in the interrupt hook is now an endpoint, proc_nr_e. . m_source for messages and notifies is now an endpoint, instead of proc number. . isokendpt() converts an endpoint to a process number, returns success (but fails if the process number is out of range, the process slot is not a living process, or the given endpoint number does not match the endpoint number in the process slot, indicating an old process). . okendpt() is the same as isokendpt(), but panic()s if the conversion fails. This is mainly used for decoding message.m_source endpoints, and other endpoint numbers in kernel data structures, which should always be correct. . if DEBUG_ENABLE_IPC_WARNINGS is enabled, isokendpt() and okendpt() get passed the __FILE__ and __LINE__ of the calling lines, and print messages about what is wrong with the endpoint number (out of range proc, empty proc, or inconsistent endpoint number), with the caller, making finding where the conversion failed easy without having to include code for every call to print where things went wrong. Sometimes this is harmless (wrong arg to a kernel call), sometimes it's a fatal internal inconsistency (bogus m_source). . some process table fields have been appended an _e to indicate it's become and endpoint. . process endpoint is stored in p_endpoint, without generation number. it turns out the kernel never needs the generation number, except when fork()ing, so it's decoded then. . kernel calls all take endpoints as arguments, not proc numbers. the one exception is sys_fork(), which needs to know in which slot to put the child.
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#if DEBUG_SCHED_CHECK
int p_ready, p_found;
#endif
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};
/* Bits for the runtime flags. A process is runnable iff p_rts_flags == 0. */
#define SLOT_FREE 0x01 /* process slot is free */
#define NO_PRIORITY 0x02 /* process has been stopped */
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#define SENDING 0x04 /* process blocked trying to send */
#define RECEIVING 0x08 /* process blocked trying to receive */
#define SIGNALED 0x10 /* set when new kernel signal arrives */
#define SIG_PENDING 0x20 /* unready while signal being processed */
#define P_STOP 0x40 /* set when process is being traced */
#define NO_PRIV 0x80 /* keep forked system process from running */
#define NO_ENDPOINT 0x100 /* process cannot send or receive messages */
Mostly bugfixes of bugs triggered by the test set. bugfixes: SYSTEM: . removed rc->p_priv->s_flags = 0; for the priv struct shared by all user processes in get_priv(). this should only be done once. doing a SYS_PRIV_USER in sys_privctl() caused the flags of all user processes to be reset, so they were no longer PREEMPTIBLE. this happened when RS executed a policy script. (this broke test1 in the test set) VFS/MFS: . chown can change the mode of a file, and chmod arguments are only part of the full file mode so the full filemode is slightly magic. changed these calls so that the final modes are returned to VFS, so that the vnode can be kept up-to-date. (this broke test11 in the test set) MFS: . lookup() checked for sizeof(string) instead of sizeof(user_path), truncating long path names (caught by test 23) . truncate functions neglected to update ctime (this broke test16) VFS: . corner case of an empty filename lookup caused fields of a request not to be filled in in the lookup functions, not making it clear that the lookup had failed, causing messages to garbage processes, causing strange failures. (caught by test 30) . trust v_size in vnode when doing reads or writes on non-special files, truncating i/o where necessary; this is necessary for pipes, as MFS can't tell when a pipe has been truncated without it being told explicitly each time. when the last reader/writer on a pipe closes, tell FS about the new size using truncate_vn(). (this broke test 25, among others) . permission check for chdir() had disappeared; added a forbidden() call (caught by test 23) new code, shouldn't change anything: . introduced RTS_SET, RTS_UNSET, and RTS_ISSET macro's, and their LOCK variants. These macros set and clear the p_rts_flags field, causing a lot of duplicated logic like old_flags = rp->p_rts_flags; /* save value of the flags */ rp->p_rts_flags &= ~NO_PRIV; if (old_flags != 0 && rp->p_rts_flags == 0) lock_enqueue(rp); to change into the simpler RTS_LOCK_UNSET(rp, NO_PRIV); so the macros take care of calling dequeue() and enqueue() (or lock_*()), as the case may be). This makes the code a bit more readable and a bit less fragile. . removed return code from do_clocktick in CLOCK as it currently never replies . removed some debug code from VFS . fixed grant debug message in device.c preemptive checks, tests, changes: . added return code checks of receive() to SYSTEM and CLOCK . O_TRUNC should never arrive at MFS (added sanity check and removed O_TRUNC code) . user_path declared with PATH_MAX+1 to let it be null-terminated . checks in MFS to see if strings passed by VFS are null-terminated IS: . static irq name table thrown out
2007-02-01 18:50:02 +01:00
/* These runtime flags can be tested and manipulated by these macros. */
#define RTS_ISSET(rp, f) (((rp)->p_rts_flags & (f)) == (f))
/* Set flag and dequeue if the process was runnable. */
#define RTS_SET(rp, f) \
do { \
if(!(rp)->p_rts_flags) { dequeue(rp); } \
(rp)->p_rts_flags |= (f); \
} while(0)
/* Clear flag and enqueue if the process was not runnable but is now. */
#define RTS_UNSET(rp, f) \
do { \
int rts; \
rts = (rp)->p_rts_flags; \
(rp)->p_rts_flags &= ~(f); \
if(rts && !(rp)->p_rts_flags) { enqueue(rp); } \
} while(0)
/* Set flag and dequeue if the process was runnable. */
#define RTS_LOCK_SET(rp, f) \
do { \
if(!(rp)->p_rts_flags) { lock_dequeue(rp); } \
(rp)->p_rts_flags |= (f); \
} while(0)
/* Clear flag and enqueue if the process was not runnable but is now. */
#define RTS_LOCK_UNSET(rp, f) \
do { \
int rts; \
rts = (rp)->p_rts_flags; \
(rp)->p_rts_flags &= ~(f); \
if(rts && !(rp)->p_rts_flags) { lock_enqueue(rp); } \
} while(0)
/* Set flags to this value. */
#define RTS_LOCK_SETFLAGS(rp, f) \
do { \
if(!(rp)->p_rts_flags && (f)) { lock_dequeue(rp); } \
(rp)->p_rts_flags = (f); \
} while(0)
/* Misc flags */
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#define REPLY_PENDING 0x01 /* reply to IPC_REQUEST is pending */
#define MF_VM 0x08 /* process uses VM */
/* Scheduling priorities for p_priority. Values must start at zero (highest
* priority) and increment. Priorities of the processes in the boot image
* can be set in table.c. IDLE must have a queue for itself, to prevent low
* priority user processes to run round-robin with IDLE.
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*/
#define NR_SCHED_QUEUES 16 /* MUST equal minimum priority + 1 */
#define TASK_Q 0 /* highest, used for kernel tasks */
#define MAX_USER_Q 0 /* highest priority for user processes */
#define USER_Q 7 /* default (should correspond to nice 0) */
#define MIN_USER_Q 14 /* minimum priority for user processes */
#define IDLE_Q 15 /* lowest, only IDLE process goes here */
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/* Magic process table addresses. */
#define BEG_PROC_ADDR (&proc[0])
#define BEG_USER_ADDR (&proc[NR_TASKS])
#define END_PROC_ADDR (&proc[NR_TASKS + NR_PROCS])
#define NIL_PROC ((struct proc *) 0)
#define NIL_SYS_PROC ((struct proc *) 1)
#define cproc_addr(n) (&(proc + NR_TASKS)[(n)])
#define proc_addr(n) (pproc_addr + NR_TASKS)[(n)]
#define proc_nr(p) ((p)->p_nr)
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#define isokprocn(n) ((unsigned) ((n) + NR_TASKS) < NR_PROCS + NR_TASKS)
#define isemptyn(n) isemptyp(proc_addr(n))
#define isemptyp(p) ((p)->p_rts_flags == SLOT_FREE)
#define iskernelp(p) iskerneln((p)->p_nr)
#define iskerneln(n) ((n) < 0)
#define isuserp(p) isusern((p)->p_nr)
#define isusern(n) ((n) >= 0)
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/* The process table and pointers to process table slots. The pointers allow
* faster access because now a process entry can be found by indexing the
* pproc_addr array, while accessing an element i requires a multiplication
* with sizeof(struct proc) to determine the address.
*/
EXTERN struct proc proc[NR_TASKS + NR_PROCS]; /* process table */
EXTERN struct proc *pproc_addr[NR_TASKS + NR_PROCS];
EXTERN struct proc *rdy_head[NR_SCHED_QUEUES]; /* ptrs to ready list headers */
EXTERN struct proc *rdy_tail[NR_SCHED_QUEUES]; /* ptrs to ready list tails */
#endif /* PROC_H */