muxDevLoad是用来加载一个网络设备的，muxDevLoad成功执行后，我们就可以在shell里调用ifconfig命令来察看load的网卡设备了。
先看一下函数的调用流程，最后大概分析一下muxDevLoad的功能。
1726 /******************************************************************************
1727 *
1728 * usrNetInit - network intialization routine called from usrConfig.c
1729 *
1730 */
1731 STATUS usrNetInit
1732 (
1733 char *bootString
1734 )
1735 {
1736 #ifdef INCLUDE_BOOT_LINE_INIT
1737 usrBootLineParse(NULL);
1738 #endif /* INCLUDE_BOOT_LINE_INIT */
1739 networkinit ();
1740 return (OK);
1741 }
该函数位于"vxworks-6.8/target/src/config/usrNetwork.c"， 调用netWorkInit（）来初始化整个网络模块。
netWorkInit()
------->usrNetEndLibInit() : "vxworks-6.8/target/src/config/usrNetwork.c"
-------->vxbDevMethodRun((UINT32)&muxDevConnect_desc, NULL); "vxworks-6.8/target/src/config/usrNetwork.c"
通过上述函数流程，可以看到vxbDevMethodRun遍历所有的注册设备，对每个设备调用muxDevConnect_desc函数，看看muxDevConnect_desc函数是哪儿定义的。
下面这段代码是从驱动：vxworks-6.8/target/src/hwif/end/an983VxbEnd.c 摘出来的。
141 LOCAL struct vxbDeviceMethod anMethods[] =
142 {
143 DEVMETHOD(miiRead, anPhyRead),
144 DEVMETHOD(miiWrite, anPhyWrite),
145 DEVMETHOD(miiMediaUpdate, anLinkUpdate),
146 DEVMETHOD(muxDevConnect, anMuxConnect),
147 DEVMETHOD(vxbDrvUnlink, anInstUnlink),
148 { 0, 0 }
149 };
anMethods是一个vxbDeviceMethod结构体数组，struct vxbDeviceMethod结构体定义如下：
266 /*
267 * An alternative method for bus controllers to provide the
268 * methods used by downstream devices. This structure is
269 * provided so that the controller can provide a null-terminated
270 * list of method/handler pairs.
271 *
272 * When a driver fetches the access methods, the standard methods
273 * are used first. If the method is not one of the standard
274 * methods (specified in the vxbAccessList structure), or if the
275 * method specified is NULL in the controller‘s standard methods,
276 * then the vxbAccessMethodsGet() routine searches through any
277 * methods listed in the pMethods field of the vxbAccessList
278 * structure.
279 *
280 * In addition, this structure is used by all devices to provide
281 * services to OS modules such as power management.
282 */
283
284 struct vxbDeviceMethod
285 {
286 UINT32 devMethodId;
287 FUNCPTR handler;
288 };
宏DEVMETHOD的定义如下：
171 /* method related macros, for driver use and method caller use */
172
173 #define DEVMETHOD(NAME, FUNC) { (UINT32)&NAME##_desc, (FUNCPTR) FUNC }
174 #define DEVMETHOD_END { 0, NULL }
175 #define METHOD_DECL(NAME) IMPORT char NAME##_desc[];
176 #define DEVMETHOD_DEF(METHOD, STRING) char METHOD##_desc[]=STRING;
177 #define DEVMETHOD_CALL(METHOD) ((UINT32)(&METHOD##_desc[0]))
从vxbDeviceMethod结构体可以看出，能通过vxbDevMethodRun函数调用的函数必须有一个函数ID，DEVMETHOD可以帮助生成vxDeviceMethod实例。
到这一步，已经可以调到一个具体驱动的muxDevConnect函数了，下面分析一个具体驱动的muxDevConnect函数。还是以an983VxbEnd.c为例，代码如下：
855 /*****************************************************************************
856 *
857 * anMuxConnect - muxConnect method handler
858 *
859 * This function handles muxConnect() events, which may be triggered
860 * manually or (more likely) by the bootstrap code. Most VxBus
861 * initialization occurs before the MUX has been fully initialized,
862 * so the usual muxDevLoad()/muxDevStart() sequence must be defered
863 * until the networking subsystem is ready. This routine will ultimately
864 * trigger a call to anEndLoad() to create the END interface instance.
865 *
866 * RETURNS: N/A
867 *
868 * ERRNO: N/A
869 */
870
871 LOCAL void anMuxConnect
872 (
873 VXB_DEVICE_ID pDev,
874 void * unused
875 )
876 {
877 AN_DRV_CTRL *pDrvCtrl;
878
879 /*
880 * Attach our ISR. For PCI, the index value is always
881 * 0, since the PCI bus controller dynamically sets
882 * up interrupts for us.
883 */
884
885 vxbIntConnect (pDev, 0, anEndInt, pDev->pDrvCtrl);
886
887 pDrvCtrl = pDev->pDrvCtrl;
888
889 /* Save the cookie. */
890
891 pDrvCtrl->anMuxDevCookie = muxDevLoad (pDev->unitNumber,
892 anEndLoad, "", TRUE, pDev);
893
894 if (pDrvCtrl->anMuxDevCookie != NULL)
895 muxDevStart (pDrvCtrl->anMuxDevCookie);
896
897 if (_func_m2PollStatsIfPoll != NULL)
898 endPollStatsInit (pDrvCtrl->anMuxDevCookie,
899 _func_m2PollStatsIfPoll);
900
901 return;
902 }
anMuxConnect首先注册中断，紧接着调用muxDevLoad函数完成网络设备的加载，传入的参数分别为设备的单元号，当同种设备有多个实例时，可以通过pDev->unitNumber区分开来。第二个参数是驱动实现的endLoad函数。最后一个是pDev指向当前网卡的设备实例指针。这三个参数比较重要。下面给出完整的muxDevLoad函数代码，从中可以看出muxDevLoad分两次调用anEndLoad函数，最终完成设备注册，通过muxDevLoad代码，可以更清楚的看到网卡实例的结构体在内核中是如何存放的。
503 /******************************************************************************
504 *
505 * muxDevLoad - load a driver into the MUX
506 *
507 * The muxDevLoad() routine loads a network driver into the MUX. Internally,
508 * this routine calls the specified <endLoad> routine to initialize the
509 * software state of the device. After the device is initialized,
510 * muxDevStart() must be called to start the device.
511 * .IP <unit> 15
512 * Expects the unit number of the device.
513 * .IP <endLoad>
514 * Expects a pointer to the network driver‘s endLoad() or nptLoad() entry
515 * point.
516 * .IP <pInitString>
517 * Expects a pointer to an initialization string, typically a colon-delimited
518 * list of options. The muxDevLoad() routine passes this along blindly to
519 * the <endLoad> function.
520 * .IP <loaning>
521 * Currently unused. Expects a boolean value that tells the MUX whether the
522 * driver supports buffer loaning on this device. If the low-level device
523 * cannot support buffer loaning, passing in TRUE has no effect.
524 * .IP <pBSP>
525 * This argument is passed blindly to the driver, which may or may not use it.
526 * It is provided so that the BSP can pass in tables of functions that the
527 * driver can use but that are specific to the particular BSP on which
528 * it runs.
529 *
530 * RETURNS: A cookie representing the new device, or NULL if an error occurred.
531 *
532 * ERRNO: S_muxLib_LOAD_FAILED
533 */
534 535 DEV_COOKIE muxDevLoad
536 (
537 int unit, /* unit number of device */
538 END_OBJ * (*endLoad) (char*, void*), /* load function of the driver */
539 char * pInitString, /* init string for this driver */
540 BOOL loaning, /* we loan buffers */
541 void * pBSP /* for BSP group */
542 )
543 {
544 END_OBJ * pNew = NULL;
545 END_TBL_ROW * pNode = NULL;
546 NODE * enode;
547 DEV_OBJ dev;
548 char initString [END_INIT_STR_MAX];
549 int endStyle;
550 MUX_END_STYLE_INFO * style;
551 int j;
552
553 bzero (initString, END_INIT_STR_MAX);
554
555 /* Create a fake END placeholder, mark it as invalid */
556
557 bzero ((caddr_t)&dev, sizeof (dev));
558 dev.unit = unit;
559 dev.muxFlags = MUX_END_FLAG_LOADING;
560 dev.refs = 1;
561
562 if (snprintf (initString, END_INIT_STR_MAX,
563 "%d:%s", unit, pInitString) >= END_INIT_STR_MAX)
564 goto muxDevLoad_errout;
565
566 /*
567 * Loading a device is a two pass algorithm.
568 *
569 * This is Pass 1.
570 *
571 * In the first pass we ask the device what its name is.
572 * The END must respect the name length limits of dev.name,
573 * END_NAME_MAX = 16 characters, including terminating NUL.
574 * Actually, the network stack imposes tighter limits in
575 * interface ioctls, for which the name (including unit number &
576 * terminating NUL) must fit in 16 bytes.
577 */
578
579 if (endLoad (dev.name, NULL) != 0)
580 goto muxDevLoad_errout;
581
582 /*
583 * Now we verify that the device hasn‘t already been loaded, and
584 * to protect against concurrent loads of the same device, we
585 * put a temporary placeholder for the END into the MUX list.
586 *
587 * We use the temporary placeholder rather than holding muxLock
588 * across the END operations since we prefer not to establish
589 * any mutex ordering between muxLock and any semaphores taken
590 * by endLoad() or the device ioctl routine.
591 */
592
593 if (semTake (muxLock, WAIT_FOREVER) != OK)
594 return NULL;
595
596 /*
597 * Consider replacing this data structure with a hash table.
598 * Consider sorting so that an iterator could be defined that
599 * traversed through the lists in a well-defined order.
600 * Consider interface indexes managed by the MUX (& consistent
601 * with the ipnet & other stacks).
602 */
603
604 for (pNode = (END_TBL_ROW *)lstFirst(&endList); pNode != NULL;
605 pNode = (END_TBL_ROW *)lstNext(&pNode->node))
606 {
607 if (strcmp (pNode->name, dev.name) == 0)
608 break;
609 }
610
611 if (pNode != NULL) /* there‘s already a row for this driver */
612 {
613 /*
614 * pNew is used temporarily here. We do not create a new END object
615 * till later.
616 */
617
618 for (enode = lstFirst(&pNode->units); enode != NULL;
619 enode = lstNext(enode))
620 {
621 pNew = member_to_object (enode, END_OBJ, devObject.node);
622 if (pNew->devObject.unit == unit)
623 {
624 if (_func_logMsg)
625 _func_logMsg ("muxDevLoad: %s%d already loaded!\n",
626 dev.name, unit);
627
628 semGive (muxLock);
629 goto muxDevLoad_errout;
630 }
631 }
632 }
633 else /* There is no row yet for this device; add one. */
634 {
635 /* MEM */
636 pNode = malloc (sizeof(END_TBL_ROW));
637 if (pNode == NULL)
638 {
639 semGive (muxLock);
640 return NULL;
641 }
642
643 bzero ((char *)pNode, sizeof(END_TBL_ROW));
644 strncpy (pNode->name, dev.name, END_NAME_MAX - 1);
645 pNode->name [END_NAME_MAX - 1] = EOS;
646 lstAdd (&endList, &pNode->node);
647 }
648
649 /*
650 * Add placeholder to list before unlocking, to protect against
651 * concurrent loads of the same device.
652 */
653
654 lstAdd (&pNode->units, &dev.node);
655
656 taskSafe (); /* stay delete-safe after unlocking */
657
658 semGive (muxLock);
659
660 /*
661 * This is Pass 2.
662 *
663 * Now that we can determine a unique number we assign that number to
664 * the device and actually load it.
665 */
666
667 pNew = (END_OBJ *)endLoad ( (char *)initString, pBSP);
668
669 if (pNew == NULL)
670 goto muxLoadErr;
671
672 if (pNew->pFuncTable == NULL || pNew->pFuncTable->ioctl == NULL)
673 goto muxLoadErr;
674
675 /* should this be done by END_OBJ_INIT() ? */
676
677 pNew->devObject.dummyBinding = pNew;
678 pNew->devObject.refs = 1;
679 pNew->devObject.muxFlags = 0;
680
681 pNew->unloadInfo = NULL;
682
683 /*
684 * There used to be stuff here to decide whether to set the
685 * END_MIB_2233 flag in pNew->flags here; that‘s obsolete in
686 * more ways than one. Removed it. (TODO: What to do instead?)
687 */
688
689 /*
690 * Determine if driver uses END or NPT interface. Default is END.
691 * END_STYLE_END2 (ipnet-native) drivers must support EIOCGSTYLE.
692 */
693
694 endStyle = END_STYLE_END;
695
696 if (pNew->pFuncTable->ioctl (pNew, EIOCGSTYLE,
697 (caddr_t) &endStyle) != OK &&
698 pNew->pFuncTable->ioctl (pNew, EIOCGNPT, NULL) == OK)
699 {
700 endStyle = END_STYLE_NPT;
701 }
702
703 pNew->endStyle = endStyle;
704
705 /*
706 * Set the native send routine and argument.
707 *
708 * TODO: may need a send wrapper to collect statistics for
709 * ENDs that don‘t set the END_MIB_2233 flag. See the old
710 * _muxTkSendEnd() and _muxTkSendNpt().
711 *
712 * Actually, endM2Init() sets END_MIB_2233 in each END
713 * depending on whether RFC 2233 support is included in
714 * the image (pMibRtn != NULL); that‘s independent of
715 * the driver. A few older drivers that don‘t call
716 * endM2Init() might set END_MIB_2233 themselves.
717 */
718 pNew->send[endStyle].func = pNew->pFuncTable->send;
719 pNew->send[endStyle].arg = pNew;
720
721 pNew->pollSend[endStyle].func = pNew->pFuncTable->pollSend;
722 pNew->pollSend[endStyle].arg = pNew;
723
724 pNew->pollRecv[endStyle].func = pNew->pFuncTable->pollRcv;
725 pNew->pollRecv[endStyle].arg = pNew;
726
727 style = &muxEndStyles[endStyle];
728
729 if ((pNew->receiveRtn = style->rxRtn) == NULL)
730 {
731 if (_func_logMsg)
732 _func_logMsg ("No support for end style %d, required by %s%n\n",
733 endStyle, pNew->devObject.name, unit);
734 }
735 pNew->rxArg = pNew; /* do we need rxArg? */
736
737 /*
738 * Install wrapper send, polled send, and polled receive
739 * functions for different supported styles
740 */
741 for (j = 0; j < NUM_END_STYLES; ++j)
742 {
743 if (j == endStyle) /* skip the native style */
744 continue;
745
746 if (style->sendWrappers[j] == NULL)
747 continue;
748
749 pNew->send[j].func = style->sendWrappers[j];
750 pNew->send[j].arg = pNew;
751 pNew->pollSend[j].func = style->pollSendWrappers[j];
752 pNew->pollSend[j].arg = pNew;
753 pNew->pollRecv[j].func = style->pollReceiveWrappers[j];
754 pNew->pollRecv[j].arg = pNew;
755 }
756
757 semTake (muxLock, WAIT_FOREVER);
758
759 taskUnsafe (); /* remove extra deletion safety count */
760
761 /* remove placeholder */
762
763 lstDelete (&pNode->units, &dev.node);
764
765 lstAdd (&pNode->units, &pNew->devObject.node);
766
767 semGive (muxLock);
768
769 return (pNew);
770
771 muxLoadErr:
772 semTake (muxLock, WAIT_FOREVER);
773
774 taskUnsafe (); /* remove extra deletion safety count */
775
776 /* remove placeholder */
777
778 lstDelete (&pNode->units, &dev.node);
779
780 if (lstCount (&pNode->units) == 0)
781 {
782 lstDelete (&endList, &pNode->node);
783 free (pNode);
784 }
785
786 semGive (muxLock);
787
788 muxDevLoad_errout:
789 errnoSet (S_muxLib_LOAD_FAILED);
790 return (NULL);
791 }
//TODO：以后再加详细注释
下面是具体驱动的andLoad函数实现：
1080 /*****************************************************************************
1081 *
1082 * anEndLoad - END driver entry point
1083 *
1084 * This routine initializes the END interface instance associated
1085 * with this device. In traditional END drivers, this function is
1086 * the only public interface, and it‘s typically invoked by a BSP
1087 * driver configuration stub. With VxBus, the BSP stub code is no
1088 * longer needed, and this function is now invoked automatically
1089 * whenever this driver‘s muxConnect() method is called.
1090 *
1091 * For older END drivers, the load string would contain various
1092 * configuration parameters, but with VxBus this use is deprecated.
1093 * The load string should just be an empty string. The second
1094 * argument should be a pointer to the VxBus device instance
1095 * associated with this device. Like older END drivers, this routine
1096 * will still return the device name if the init string is empty,
1097 * since this behavior is still expected by the MUX. The MUX will
1098 * invoke this function twice: once to obtain the device name,
1099 * and then again to create the actual END_OBJ instance.
1100 *
1101 * When this function is called the second time, it will initialize
1102 * the END object, perform MIB2 setup, allocate a buffer pool, and
1103 * initialize the supported END capabilities. The only special
1104 * capability we support is VLAN_MTU, since we can receive slightly
1105 * larger than normal frames.
1106 *
1107 * RETURNS: An END object pointer, or NULL on error, or 0 and the name
1108 * of the device if the <loadStr> was empty.
1109 *
1110 * ERRNO: N/A
1111 */
1112
1113 LOCAL END_OBJ *anEndLoad
1114 (
1115 char * loadStr,
1116 void * pArg
1117 )
1118 {
1119 AN_DRV_CTRL *pDrvCtrl;
1120 VXB_DEVICE_ID pDev;
1121
1122 /* Make the MUX happy. */
1123
1124 if (loadStr == NULL)
1125 return NULL;
1126
1127 if (loadStr[0] == 0)
1128 {
1129 bcopy (AN_NAME, loadStr, sizeof(AN_NAME));
1130 return NULL;
1131 }
1132
1133 pDev = pArg;
1134 pDrvCtrl = pDev->pDrvCtrl;
1135
1136 if (END_OBJ_INIT (&pDrvCtrl->anEndObj, NULL, pDev->pName,
1137 pDev->unitNumber, &anNetFuncs,
1138 "Infineon AN983 VxBus END Driver") == ERROR)
1139 {
1140 logMsg("%s%d: END_OBJ_INIT failed\n", (int)AN_NAME,
1141 pDev->unitNumber, 0, 0, 0, 0);
1142 return (NULL);
1143 }
1144
1145 endM2Init (&pDrvCtrl->anEndObj, M2_ifType_ethernet_csmacd,
1146 pDrvCtrl->anAddr, ETHER_ADDR_LEN, ETHERMTU, 100000000,
1147 IFF_NOTRAILERS | IFF_SIMPLEX | IFF_MULTICAST | IFF_BROADCAST);
1148
1149 /* Allocate a buffer pool */
1150
1151 if (endPoolCreate (256, &pDrvCtrl->anEndObj.pNetPool) == ERROR)
1152 {
1153 logMsg("%s%d: pool creation failed\n", (int)AN_NAME,
1154 pDev->unitNumber, 0, 0, 0, 0);
1155 return (NULL);
1156 }
1157
1158 pDrvCtrl->anPollBuf = netTupleGet(pDrvCtrl->anEndObj.pNetPool,
1159 AN_CLSIZE, M_DONTWAIT, MT_DATA, 0);
1160
1161 /* Set up capabilities. */
1162
1163 pDrvCtrl->anCaps.cap_available = IFCAP_VLAN_MTU;
1164 pDrvCtrl->anCaps.cap_enabled = IFCAP_VLAN_MTU;
1165
1166 return (&pDrvCtrl->anEndObj);
1167 }
时间： 2024-08-03 15:02:12