Annotation of coherent/b/STREAMS/conf/streams/src/ddi_data.c, revision 1.1

1.1     ! root        1: #define        _DDI_DKI        1
        !             2: #define        _DDI_DKI_IMPL   1
        !             3: #define        _SYSV4          1
        !             4: 
        !             5: /*
        !             6:  * Definition for the DDI/DKI linkable version of ddi_proc ()
        !             7:  */
        !             8: 
        !             9: /*
        !            10:  *-IMPORTS:
        !            11:  *     <common/ccompat.h>
        !            12:  *             __USE_PROTO__
        !            13:  *             __ARGS ()
        !            14:  *     <kernel/x86lock.h>
        !            15:  *             ATOMIC_STORE_UCHAR ()
        !            16:  *     <kernel/ddi_lock.h>
        !            17:  *             INTERNAL_LOCK
        !            18:  *             poll_global_hierarchy
        !            19:  *             poll_global_priority
        !            20:  *             defer_hierarchy
        !            21:  *             defer_priority
        !            22:  *             proc_global_hierarchy
        !            23:  *             proc_global_priority
        !            24:  *     <sys/types.h>
        !            25:  *             inb ()
        !            26:  *             outb ()
        !            27:  *     <sys/ksynch.h>
        !            28:  *             lkinfo_t
        !            29:  *             LOCK_ALLOC ()
        !            30:  *     <sys/kmem.h>
        !            31:  *             KM_NOSLEEP
        !            32:  *             kmem_alloc ()
        !            33:  *     <stddef.h>
        !            34:  *             NULL
        !            35:  *     <string.h>
        !            36:  *             memset ()
        !            37:  */
        !            38: 
        !            39: #include <common/ccompat.h>
        !            40: #include <kernel/x86lock.h>
        !            41: #include <kernel/ddi_lock.h>
        !            42: #include <sys/types.h>
        !            43: #include <sys/ksynch.h>
        !            44: #include <sys/kmem.h>
        !            45: #include <stddef.h>
        !            46: #include <string.h>
        !            47: 
        !            48: #include <kernel/ddi_base.h>
        !            49: #include <kernel/ddi_proc.h>
        !            50: #include <kernel/ddi_cpu.h>
        !            51: #include <kernel/ddi_glob.h>
        !            52: 
        !            53: 
        !            54: /*
        !            55:  * Here we have the actal static data declarations for the uniprocessor
        !            56:  * implementation of the DDI/DKI per-CPU data. Note that under a "real"
        !            57:  * system, the dynamic area would be the space left over by the fixed data up
        !            58:  * to the size of a page, because that seems the best (read fastest and most
        !            59:  * secure) way of doing it (by mapping each processor's private data into the
        !            60:  * same address across all processors). Of course, it's questionable whether
        !            61:  * any drivers *will* actually use the binary-compatible function-versions of
        !            62:  * the accessors, but that's not our problem.
        !            63:  *
        !            64:  * Don't forget that if we *do* use the paging system for per-CPU data that
        !            65:  * those pages will have to be mapped somewhere else as well, because there is
        !            66:  * data like the deferred function table that the world may want controlled
        !            67:  * access to.
        !            68:  */
        !            69: 
        !            70: dcdata_t       __ddi_cpu_data [1];
        !            71: dgdata_t       __ddi_global_data;
        !            72: __LOCAL__ char ddi_cpu_dynarea [512];
        !            73: 
        !            74: 
        !            75: /*
        !            76:  * Lock information structures.
        !            77:  */
        !            78: 
        !            79: __LOCAL__ lkinfo_t poll_global_lkinfo = {
        !            80:        "polling global lock", INTERNAL_LOCK
        !            81: };
        !            82: 
        !            83: __LOCAL__ lkinfo_t defer_lkinfo = {
        !            84:        "defer write lock", INTERNAL_LOCK
        !            85: };
        !            86: 
        !            87: __LOCAL__ lkinfo_t proc_global_lkinfo = {
        !            88:        "process global lock", INTERNAL_LOCK
        !            89: };
        !            90: 
        !            91: 
        !            92: /*
        !            93:  *-STATUS:
        !            94:  *     Local DDI/DKI extension
        !            95:  *
        !            96:  *-NAME:
        !            97:  *     ddi_base_data           Get per-process DDI/DKI base data.
        !            98:  *
        !            99:  *-SYNOPSIS:
        !           100:  *     #include <kernel/ddi_base.h>
        !           101:  *
        !           102:  *     dbdata_t * ddi_base_data (void);
        !           103:  *
        !           104:  *-DESCRIPTION:
        !           105:  *     This function returns a base pointer to a table of information that
        !           106:  *     the DDI/DKI needs to associate with a process but will not need to
        !           107:  *     access outside that process context.
        !           108:  *
        !           109:  *-RETURN VALUE:
        !           110:  *     The base address of a per-process DDI/DKI data table entry. The
        !           111:  *     value returned may be considered "constant" and memoized within a
        !           112:  *     context provided that no rescheduling may occur.
        !           113:  *
        !           114:  *-LEVEL:
        !           115:  *     Base only.
        !           116:  *
        !           117:  *-NOTES:
        !           118:  *     This function does not sleep.
        !           119:  */
        !           120: 
        !           121: 
        !           122: #if    __USE_PROTO__
        !           123: dbdata_t * (ddi_base_data) (void)
        !           124: #else
        !           125: dbdata_t *
        !           126: ddi_base_data __ARGS (())
        !           127: #endif
        !           128: {
        !           129:        ASSERT_BASE_LEVEL ();
        !           130: 
        !           131:        return ddi_base_data ();
        !           132: }
        !           133: 
        !           134: 
        !           135: /*
        !           136:  *-STATUS:
        !           137:  *     Local DDI/DKI extension
        !           138:  *
        !           139:  *-NAME:
        !           140:  *     ddi_proc_data           Get per-process DDI/DKI global data.
        !           141:  *
        !           142:  *-SYNOPSIS:
        !           143:  *     #include <kernel/ddi_proc.h>
        !           144:  *
        !           145:  *     dpdata_t * ddi_proc_data (void);
        !           146:  *
        !           147:  *-DESCRIPTION:
        !           148:  *     This function returns a base pointer to a table of information that
        !           149:  *     the DDI/DKI needs to associate with a process but may need to access
        !           150:  *     outside the process context.
        !           151:  *
        !           152:  *-RETURN VALUE:
        !           153:  *     The base address of a per-process DDI/DKI data table entry. The
        !           154:  *     value returned may be considered "constant" and memoized within a
        !           155:  *     context provided that no rescheduling may occur.
        !           156:  *
        !           157:  *-LEVEL:
        !           158:  *     Base or interrupt.
        !           159:  *
        !           160:  *-NOTES:
        !           161:  *     This function does not sleep.
        !           162:  */
        !           163: 
        !           164: 
        !           165: #if    __USE_PROTO__
        !           166: dpdata_t * (ddi_proc_data) (void)
        !           167: #else
        !           168: dpdata_t *
        !           169: ddi_proc_data __ARGS (())
        !           170: #endif
        !           171: {
        !           172:        return ddi_proc_data ();
        !           173: }
        !           174: 
        !           175: 
        !           176: /*
        !           177:  *-STATUS:
        !           178:  *     Local DDI/DKI extension
        !           179:  *
        !           180:  *-NAME:
        !           181:  *     ddi_cpu_data            Get per-CPU DDI/DKI global data.
        !           182:  *
        !           183:  *-SYNOPSIS:
        !           184:  *     #include <kernel/ddi_cpu.h>
        !           185:  *
        !           186:  *     dcdata_t * ddi_cpu_data (void);
        !           187:  *
        !           188:  *-DESCRIPTION:
        !           189:  *     This function returns a base pointer to a table of information that
        !           190:  *     can be considered per-CPU DDI/DKI static data. The value returned
        !           191:  *     may be considered "constant" and memoized within a context provided
        !           192:  *     that no rescheduling could occur.
        !           193:  *
        !           194:  *-RETURN VALUE:
        !           195:  *     The base address of a per-CPU DDI/DKI data table entry.
        !           196:  *
        !           197:  *-LEVEL:
        !           198:  *     Base or interrupt.
        !           199:  *
        !           200:  *-NOTES:
        !           201:  *     This function does not sleep.
        !           202:  */
        !           203: 
        !           204: #if    __USE_PROTO__
        !           205: dcdata_t * (ddi_cpu_data) (void)
        !           206: #else
        !           207: dcdata_t *
        !           208: ddi_cpu_data __ARGS (())
        !           209: #endif
        !           210: {
        !           211:        return ddi_cpu_data ();
        !           212: }
        !           213: 
        !           214: 
        !           215: /*
        !           216:  *-STATUS:
        !           217:  *     Local DDI/DKI extension
        !           218:  *
        !           219:  *-NAME:
        !           220:  *     ddi_global_data         Get DDI/DKI global data.
        !           221:  *
        !           222:  *-SYNOPSIS:
        !           223:  *     #include <kernel/ddi_glob.h>
        !           224:  *
        !           225:  *     dgdata_t * ddi_global_data (void);
        !           226:  *
        !           227:  *-DESCRIPTION:
        !           228:  *     This function returns a base pointer to a table of information that
        !           229:  *     represents the global state of the DDI/DKI subsystem, with the
        !           230:  *     possible exception of the STREAMS global state.
        !           231:  *
        !           232:  *-RETURN VALUE:
        !           233:  *     The base address of the global DDI/DKI data table. The value returned
        !           234:  *     may be considered "constant" and memoized within a context provided
        !           235:  *     that no rescheduling may occur.
        !           236:  *
        !           237:  *-LEVEL:
        !           238:  *     Base or interrupt.
        !           239:  *
        !           240:  *-NOTES:
        !           241:  *     This function does not sleep.
        !           242:  */
        !           243: 
        !           244: 
        !           245: #if    __USE_PROTO__
        !           246: dgdata_t * (ddi_global_data) (void)
        !           247: #else
        !           248: dgdata_t *
        !           249: ddi_global_data __ARGS (())
        !           250: #endif
        !           251: {
        !           252:        return ddi_global_data ();
        !           253: }
        !           254: 
        !           255: 
        !           256: /*
        !           257:  *-STATUS:
        !           258:  *     For the Implementors only.
        !           259:  *
        !           260:  *-NAME:
        !           261:  *     ddi_cpu_id      Determine the current CPU id.
        !           262:  *
        !           263:  *-SYNOPSIS:
        !           264:  *     #include <kernel/ddi_cpu.h>
        !           265:  *
        !           266:  *     processorid_t ddi_cpu_id (void);
        !           267:  *
        !           268:  *-DESCRIPTION:
        !           269:  *     ddi_cpu_id () allows DDI/DKI code a way of accessing the current CPU
        !           270:  *     id for passing to functions such as dtimeout () or defer_int_cpu ().
        !           271:  *
        !           272:  *-RETURN VALUE:
        !           273:  *     The id code of the CPU that the caller is executing on.
        !           274:  *
        !           275:  *-LEVEL:
        !           276:  *     Base or interrupt.
        !           277:  *
        !           278:  *-NOTES:
        !           279:  *     Does not sleep.
        !           280:  */
        !           281: 
        !           282: #if    __USE_PROTO__
        !           283: processorid_t (ddi_cpu_id) (void)
        !           284: #else
        !           285: processorid_t
        !           286: ddi_cpu_id __ARGS (())
        !           287: #endif
        !           288: {
        !           289:        return ddi_cpu_data ()->dc_cpuid;
        !           290: }
        !           291: 
        !           292: 
        !           293: /*
        !           294:  *-STATUS:
        !           295:  *     For the Implementors only.
        !           296:  *
        !           297:  *-NAME:
        !           298:  *     ddi_cpu_alloc   Dynamically allocates per-CPU data.
        !           299:  *
        !           300:  *-SYNOPSIS:
        !           301:  *     #include <kernel/ddi_cpu.h>
        !           302:  *
        !           303:  *     void * ddi_cpu_alloc (size_t size);
        !           304:  *
        !           305:  *-ARGUMENTS:
        !           306:  *     size            The size in bytes to allocate. This value will always
        !           307:  *                     be rounded up to the size of an integer to ensure the
        !           308:  *                     alignment of the returned space. A value of 0 is not
        !           309:  *                     legal and will result in the function returning NULL.
        !           310:  *
        !           311:  *-DESCRIPTION:
        !           312:  *     ddi_cpu_alloc () is for use in the DDI/DKI implementation to request
        !           313:  *     per-CPU data in a flexible way. Facilities that require tables of per-
        !           314:  *     CPU data should request it at startup time to allow the table sizes to
        !           315:  *     be flexibly administered and also to avoid polluting the "dcdata_t"
        !           316:  *     structure with information whose size cannot easily be fixed. Using
        !           317:  *     this facility should allow for greater levels of internal binary
        !           318:  *     compatibility by restricting the amount of change the "dcdata_t"
        !           319:  *     structure can undergo between (minor) releases of the operation
        !           320:  *     system.
        !           321:  *
        !           322:  *-RETURN VALUE:
        !           323:  *     On failure, NULL is returned. On success, a pointer to the requested
        !           324:  *     data is returned. The pointer returned will be aligned to the size of
        !           325:  *     an integer on the target machine architecture.
        !           326:  *
        !           327:  *-LEVEL:
        !           328:  *     Base only.
        !           329:  *
        !           330:  *-NOTES:
        !           331:  *     Does not sleep.
        !           332:  */
        !           333: 
        !           334: #if    __USE_PROTO__
        !           335: __VOID__ * (ddi_cpu_alloc) (size_t size)
        !           336: #else
        !           337: __VOID__ *
        !           338: ddi_cpu_alloc __ARGS ((size))
        !           339: size_t         size;
        !           340: #endif
        !           341: {
        !           342:        dcdata_t      * dcdatap = ddi_cpu_data ();
        !           343:        __VOID__      * alloc;
        !           344: 
        !           345:        ASSERT_BASE_LEVEL ();
        !           346: 
        !           347:        size = (size + sizeof (int) - 1) & ~ sizeof (int);
        !           348: 
        !           349:        if (size == 0 || dcdatap->dc_dynalloc + size > dcdatap->dc_dynend)
        !           350:                return NULL;
        !           351: 
        !           352:        alloc = dcdatap->dc_dynalloc;
        !           353:        dcdatap->dc_dynalloc += size;
        !           354: 
        !           355:         memset (alloc, 0, size);
        !           356:        return alloc;
        !           357: }
        !           358: 
        !           359: 
        !           360: /*
        !           361:  *-STATUS:
        !           362:  *     For the Implementors only.
        !           363:  *
        !           364:  *-NAME:
        !           365:  *     ddi_cpu_other           Return per-CPU data for other CPUs
        !           366:  *
        !           367:  *-SYNOPSIS:
        !           368:  *     #include <kernel/ddi_cpu.h>
        !           369:  *
        !           370:  *     dcdata_t * ddi_cpu_ref (processorid_t cpu);
        !           371:  *
        !           372:  *-ARGUMENTS:
        !           373:  *     cpu             ID code for processor whose data needs to be accessed.
        !           374:  *
        !           375:  *-DESCRIPTION:
        !           376:  *     The implementations of DDI/DKI facilities may wish to write into the
        !           377:  *     private data areas of other CPUs. This function provides a way of
        !           378:  *     accessing that information.
        !           379:  *
        !           380:  *     Note that the per-CPU data area provides many conveniences to the
        !           381:  *     implementor, not the least of which is latitude with synchronization,
        !           382:  *     which has a data space cost if not a run-time cost, and also makes
        !           383:  *     many operations considerably simpler. Access by other CPUs to per-CPU
        !           384:  *     data bypasses most of the assumptions that can be conveniently made
        !           385:  *     about access to this area, so users of this function are especially
        !           386:  *     cautioned to use all the appropriate interlock mechanisms when writing
        !           387:  *     data via the pointer this function provides.
        !           388:  *
        !           389:  *     There must be exactly one call to ddi_cpu_unref () for each call to
        !           390:  *     ddi_cpu_ref (). This should be done as soon as possible after the
        !           391:  *     call to ddi_cpu_ref () since on some architectures making this memory
        !           392:  *     shared may have a serious impact on performance.
        !           393:  *
        !           394:  *-RETURN VALUE:
        !           395:  *     NULL is returned if the cpu ID is not valid for the machine
        !           396:  *     configuration. Otherwise, a pointer to the per-process data for the
        !           397:  *     indicated CPU is returned.
        !           398:  *
        !           399:  *-LEVEL:
        !           400:  *     Base or interrupt.
        !           401:  *
        !           402:  *-NOTES:
        !           403:  *     Does not sleep.
        !           404:  *
        !           405:  *     It is as yet uspecified whether recursive calls to ddi_cpu_ref () are
        !           406:  *     permitted.
        !           407:  */
        !           408: 
        !           409: #if    __USE_PROTO__
        !           410: dcdata_t * (ddi_cpu_ref) (processorid_t cpu)
        !           411: #else
        !           412: dcdata_t *
        !           413: ddi_cpu_ref __ARGS ((cpu))
        !           414: processorid_t  cpu;
        !           415: #endif
        !           416: {
        !           417:        /*
        !           418:         * Only one processor, as yet.
        !           419:         */
        !           420: 
        !           421:        return cpu == 0 ? ddi_cpu_data () : NULL;
        !           422: }
        !           423: 
        !           424: 
        !           425: /*
        !           426:  *-STATUS:
        !           427:  *     For the Implementors only.
        !           428:  *
        !           429:  *-NAME:
        !           430:  *     ddi_cpu_other           Return per-CPU data for other CPUs
        !           431:  *
        !           432:  *-SYNOPSIS:
        !           433:  *     #include <kernel/ddi_cpu.h>
        !           434:  *
        !           435:  *     void ddi_cpu_unref (dcdata_t * data);
        !           436:  *
        !           437:  *-ARGUMENTS:
        !           438:  *     data            A pointer to per-CPU data obtained via the
        !           439:  *                     ddi_cpu_ref () function.
        !           440:  *
        !           441:  *-DESCRIPTION:
        !           442:  *     This function is used to release a reference to per-CPU data for some
        !           443:  *     CPU that was obtained by ddi_cpu_ref (). This function may perform
        !           444:  *     various actions to undo any work necessary to ensure that the memory
        !           445:  *     in question can be accessed by the calling CPU, such as unmapping it
        !           446:  *     from the calling CPU's address space to provide maximum protection
        !           447:  *     against accidental damage.
        !           448:  *
        !           449:  *     There must be exactly one call to ddi_cpu_unref () for each call to
        !           450:  *     ddi_cpu_ref ().
        !           451:  *
        !           452:  *-RETURN VALUE:
        !           453:  *     None.
        !           454:  *
        !           455:  *-LEVEL:
        !           456:  *     Base or interrupt.
        !           457:  *
        !           458:  *-NOTES:
        !           459:  *     Does not sleep.
        !           460:  */
        !           461: 
        !           462: #if    __USE_PROTO__
        !           463: void (ddi_cpu_unref) (dcdata_t * data)
        !           464: #else
        !           465: void
        !           466: ddi_cpu_unref __ARGS ((data))
        !           467: dcdata_t      *        data;
        !           468: #endif
        !           469: {
        !           470:        ASSERT (data != NULL && data == ddi_cpu_data ());
        !           471: }
        !           472: 
        !           473: 
        !           474: /*
        !           475:  * Do what we need to do to ensure that the spl... () functions work.
        !           476:  */
        !           477: 
        !           478: #include <sys/inline.h>
        !           479: 
        !           480: __EXTERN_C__
        !           481: #if    __USE_PROTO__
        !           482: int (INTR_INIT) (void)
        !           483: #else
        !           484: int
        !           485: INTR_INIT __ARGS (())
        !           486: #endif
        !           487: {
        !           488:        dcdata_t      * dcdatap;
        !           489: 
        !           490:        /*
        !           491:         * This implementation statically allocates the per-CPU data, since
        !           492:         * deep down we really "know" that we are working on a uniprocessor.
        !           493:         * This also means we don't have to zero-fill anything.
        !           494:         */
        !           495: 
        !           496:        dcdatap = ddi_cpu_data ();
        !           497:        dcdatap->dc_base_mask = (inb (__SPICM__) << 8) | inb (__PICM__);
        !           498: 
        !           499: 
        !           500:        /*
        !           501:         * We start at interrupt level 1 so we can trap attempts to go to
        !           502:         * sleep before we are ready for that.
        !           503:         */
        !           504: 
        !           505:        dcdatap->dc_int_level = 0;
        !           506:        dcdatap->dc_ipl = plbase;
        !           507: 
        !           508: 
        !           509:        /*
        !           510:         * Set up the "dynamic" part of the structures.
        !           511:         */
        !           512: 
        !           513:        dcdatap->dc_dynalloc = ddi_cpu_dynarea;
        !           514:        dcdatap->dc_dynend = ddi_cpu_dynarea + sizeof (ddi_cpu_dynarea);
        !           515: 
        !           516: 
        !           517:        /*
        !           518:         * Carve off some of the "dynamic" space for the heirarchy-test stuff.
        !           519:         * This is done with the dynamic stuff because it seems like a really
        !           520:         * bad idea putting a table in space we want to form the basis of an
        !           521:         * internal binary standard (even though this is a very well-defined
        !           522:         * array).
        !           523:         */
        !           524: 
        !           525:        dcdatap->dc_hierarchy_cnt = (__lkhier_t *)
        !           526:                ddi_cpu_alloc (sizeof (__lkhier_t) *
        !           527:                               (__MAX_HIERARCHY__ - __MIN_HIERARCHY__ + 1));
        !           528: 
        !           529:        return dcdatap->dc_hierarchy_cnt == NULL;
        !           530: }
        !           531: 
        !           532: 
        !           533: /*
        !           534:  * Set up one of the deferred-function tables.
        !           535:  */
        !           536: 
        !           537: #if    __USE_PROTO__
        !           538: __LOCAL__ int (DEFER_INIT) (defer_t * deferp, int local, int max)
        !           539: #else
        !           540: __LOCAL__ int
        !           541: DEFER_INIT __ARGS ((deferp, local, max))
        !           542: defer_t              * deferp;
        !           543: int            local;
        !           544: int            max;
        !           545: #endif
        !           546: {
        !           547:        deferp->df_tab = (__deffuncp_t *) (local == 0 ?
        !           548:                kmem_alloc (sizeof (__deffuncp_t) * max, KM_NOSLEEP) :
        !           549:                ddi_cpu_alloc (sizeof (__deffuncp_t) * max));
        !           550: 
        !           551:        deferp->df_wlock = LOCK_ALLOC (defer_hierarchy, defer_priority,
        !           552:                                       & defer_lkinfo, KM_NOSLEEP);
        !           553: 
        !           554:        if (deferp->df_tab == NULL || deferp->df_wlock == NULL)
        !           555:                return 1;
        !           556: 
        !           557:        ATOMIC_STORE_UCHAR (deferp->df_max, max);
        !           558:        return 0;
        !           559: }
        !           560: 
        !           561: 
        !           562: /*
        !           563:  * Set up the global and per-CPU DDI/DKI data, locks and other whatnot.
        !           564:  */
        !           565: 
        !           566: __EXTERN_C__
        !           567: #if    __USE_PROTO__
        !           568: int (DDI_GLOB_INIT) (void)
        !           569: #else
        !           570: int
        !           571: DDI_GLOB_INIT __ARGS (())
        !           572: #endif
        !           573: {
        !           574:        dgdata_t      * dgdatap = ddi_global_data ();
        !           575:        dcdata_t      * dcdatap = ddi_cpu_data ();
        !           576: 
        !           577:        /*
        !           578:         * Set up the global data table. We assume here that our global data
        !           579:         * is zeroed by default.
        !           580:         */
        !           581: 
        !           582:        if (DEFER_INIT (& dgdatap->dg_defint, 0, 25) != 0 ||
        !           583:            DEFER_INIT (& dgdatap->dg_defproc, 0, 25) != 0 ||
        !           584:            DEFER_INIT (& dcdatap->dc_defint, 1, 25) != 0 ||
        !           585:            DEFER_INIT (& dcdatap->dc_defproc, 1, 25) != 0)
        !           586:                return 1;
        !           587: 
        !           588:        dgdatap->dg_polllock = LOCK_ALLOC (poll_global_hierarchy,
        !           589:                                           poll_global_priority,
        !           590:                                           & poll_global_lkinfo, KM_NOSLEEP);
        !           591: 
        !           592:        dgdatap->dg_proclock = LOCK_ALLOC (proc_global_hierarchy,
        !           593:                                           proc_global_priority,
        !           594:                                           & proc_global_lkinfo, KM_NOSLEEP);
        !           595: 
        !           596:        if (dgdatap->dg_polllock == NULL || dgdatap->dg_proclock == NULL)
        !           597:                return 1;
        !           598: 
        !           599:        return 0;
        !           600: }

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