Changeset 81122 in vbox for trunk/src/VBox/Devices/VirtIO

Timestamp:

Oct 7, 2019 8:54:00 AM (5 years ago)

Author:

vboxsync

Message:

Storage/DevVirtioSCSI.cpp: Got MSI-X support implemented and a few other small inconsequential tweaks

Location:

trunk/src/VBox/Devices/VirtIO

Files:

• Virtio_1_0.cpp (modified) (16 diffs)
• Virtio_1_0.h (modified) (3 diffs)
• Virtio_1_0_impl.h (modified) (2 diffs)

trunk/src/VBox/Devices/VirtIO/Virtio_1_0.cpp

@@ -366 +366 @@
 
     AssertMsgReturnVoid(DRIVER_OK(pVirtio), ("Guest driver not in ready state.\n"));
-
-    if (pVirtio->uMsixConfig == VIRTIO_MSI_NO_VECTOR)
-    {
-        if (pVirtio->uDriverFeatures & VIRTIO_F_EVENT_IDX)
-        {
-            if (pVirtq->fEventThresholdReached)
-            {
-                virtioRaiseInterrupt(pVirtio, VIRTIO_ISR_VIRTQ_INTERRUPT, fForce);
-                pVirtq->fEventThresholdReached = false;
-                return;
-            }
-            Log6Func(("...skipping interrupt: VIRTIO_F_EVENT_IDX set but threshold not reached\n"));
-        }
-        else
-        {
-            /** If guest driver hasn't suppressed interrupts, interrupt  */
-            if (fForce || !(virtioReadUsedFlags(pVirtio, qIdx) & VIRTQ_AVAIL_F_NO_INTERRUPT))
-            {
-                virtioRaiseInterrupt(pVirtio, VIRTIO_ISR_VIRTQ_INTERRUPT, fForce);
-                return;
-            }
-            Log6Func(("...skipping interrupt. Guest flagged VIRTQ_AVAIL_F_NO_INTERRUPT for queue\n"));
-        }
-    }
-    else
-    {
-        /* TBD, do MSI notification if criteria met */
+    if (pVirtio->uDriverFeatures & VIRTIO_F_EVENT_IDX)
+    {
+        if (pVirtq->fEventThresholdReached)
+        {
+            virtioKick(pVirtio, VIRTIO_ISR_VIRTQ_INTERRUPT, pVirtio->uQueueMsixVector[qIdx], fForce);
+            pVirtq->fEventThresholdReached = false;
+            return;
+        }
+        Log6Func(("...skipping interrupt: VIRTIO_F_EVENT_IDX set but threshold not reached\n"));
+    }
+    else
+    {
+        /** If guest driver hasn't suppressed interrupts, interrupt  */
+        if (fForce || !(virtioReadUsedFlags(pVirtio, qIdx) & VIRTQ_AVAIL_F_NO_INTERRUPT))
+        {
+            virtioKick(pVirtio, VIRTIO_ISR_VIRTQ_INTERRUPT, pVirtio->uQueueMsixVector[qIdx], fForce);
+            return;
+        }
+        Log6Func(("...skipping interrupt. Guest flagged VIRTQ_AVAIL_F_NO_INTERRUPT for queue\n"));
     }
 }
@@ -425 +417 @@
 }
 
-/**
- * Raise interrupt.
+
+/**
+ * Raise interrupt or MSI-X
  *
  * @param   pVirtio         The device state structure.
  * @param   uCause          Interrupt cause bit mask to set in PCI ISR port.
- */
-static int virtioRaiseInterrupt(PVIRTIOSTATE pVirtio, uint8_t uCause, bool fForce)
+ * @param   uVec            MSI-X vector, if enabled
+ * @param   uForce          True of out-of-band
+ */
+static int virtioKick(PVIRTIOSTATE pVirtio, uint8_t uCause, uint16_t uMsixVector, bool fForce)
 {
 
@@ -443 +438 @@
        Log6Func(("reason: device config change\n"));
 
-    pVirtio->uISR |= uCause;
-    PDMDevHlpPCISetIrq(pVirtio->CTX_SUFF(pDevIns), 0, 1);
+    if (!pVirtio->fMsiSupport)
+    {
+        pVirtio->uISR |= uCause;
+        PDMDevHlpPCISetIrq(pVirtio->CTX_SUFF(pDevIns), 0, PDM_IRQ_LEVEL_HIGH);
+    }
+    else if (uMsixVector != VIRTIO_MSI_NO_VECTOR)
+    {
+        Log6Func(("MSI-X enabled, calling PDMDevHlpPCISetIrq with vector: 0x%x\n", uMsixVector));
+        PDMDevHlpPCISetIrq(pVirtio->CTX_SUFF(pDevIns), uMsixVector, 1);
+    }
     return VINF_SUCCESS;
 }
@@ -455 +458 @@
 static void virtioLowerInterrupt(PVIRTIOSTATE pVirtio)
 {
-    PDMDevHlpPCISetIrq(pVirtio->CTX_SUFF(pDevIns), 0, 0);
+    PDMDevHlpPCISetIrq(pVirtio->CTX_SUFF(pDevIns), 0, PDM_IRQ_LEVEL_LOW);
 }
 
@@ -466 +469 @@
     pVirtio->uQueueSize[qIdx] = VIRTQ_MAX_SIZE;
     pVirtio->uQueueNotifyOff[qIdx] = qIdx;
-}
-
+
+    pVirtio->uQueueMsixVector[qIdx] = qIdx + 2;
+    if (!pVirtio->fMsiSupport) /* VirtIO 1.0, 4.1.4.3 and 4.1.5.1.2 */
+        pVirtio->uQueueMsixVector[qIdx] = VIRTIO_MSI_NO_VECTOR;
+}
 
 static void virtioResetDevice(PVIRTIOSTATE pVirtio)
@@ -478 +484 @@
     pVirtio->uISR                   = 0;
 
-#ifndef MSIX_SUPPORT
-    /** This is required by VirtIO 1.0 specification, section 4.1.5.1.2 */
-    pVirtio->uMsixConfig = VIRTIO_MSI_NO_VECTOR;
-    for (int i = 0; i < VIRTQ_MAX_CNT; i++)
-        pVirtio->uQueueMsixVector[i] = VIRTIO_MSI_NO_VECTOR;
-#endif
+
+    if (!pVirtio->fMsiSupport)  /* VirtIO 1.0, 4.1.4.3 and 4.1.5.1.2 */
+        pVirtio->uMsixConfig = VIRTIO_MSI_NO_VECTOR;
 
     pVirtio->uNumQueues = VIRTQ_MAX_CNT;
@@ -523 +526 @@
     {
         pVirtio->fGenUpdatePending = true;
-        virtioRaiseInterrupt(pVirtio, VIRTIO_ISR_DEVICE_CONFIG, false /* fForce */);
+        virtioKick(pVirtio, VIRTIO_ISR_DEVICE_CONFIG, pVirtio->uMsixConfig, false /* fForce */);
     }
 }
@@ -529 +532 @@
 /**
  * Invoked by this implementation when guest driver resets the device.
- * The driver itself will not reset until the device has read the status change.
+ * The driver itself will not  until the device has read the status change.
  */
 static void virtioGuestResetted(PVIRTIOSTATE pVirtio)
@@ -1015 +1018 @@
                       VIRTIOHANDLE          *phVirtio,
                       PVIRTIOPCIPARAMS       pPciParams,
-                      const char             *pcszInstance,
+                      const char            *pcszInstance,
                       uint64_t               uDevSpecificFeatures,
                       PFNVIRTIODEVCAPREAD    devCapReadCallback,
@@ -1028 +1031 @@
                       void                  *pDevSpecificCfg)
 {
+
+    extern PDMDEVREG g_DeviceVirtioSCSI;
+
     PVIRTIOSTATE pVirtio = (PVIRTIOSTATE)RTMemAllocZ(sizeof(VIRTIOSTATE));
     if (!pVirtio)
@@ -1034 +1040 @@
         return VERR_NO_MEMORY;
     }
+
+#ifdef VBOX_WITH_MSI_DEVICES
+    pVirtio->fMsiSupport = true;
+#endif
 
     pVirtio->pClientContext = pClientContext;
@@ -1109 +1119 @@
 
     /* Construct & map PCI vendor-specific capabilities for virtio host negotiation with guest driver */
-
-#if 0 && defined(VBOX_WITH_MSI_DEVICES)  /* T.B.D. */
-    uint8_t fMsiSupport = true;
-#else
-    uint8_t fMsiSupport = false;
-#endif
 
     /* The following capability mapped via VirtIO 1.0: struct virtio_pci_cfg_cap (VIRTIO_PCI_CFG_CAP_T)
@@ -1184 +1188 @@
     pCfg->uCapVndr = VIRTIO_PCI_CAP_ID_VENDOR;
     pCfg->uCapLen  = sizeof(VIRTIO_PCI_CFG_CAP_T);
-    pCfg->uCapNext = (fMsiSupport || pVirtio->pDevSpecificCfg) ? CFGADDR2IDX(pCfg) + pCfg->uCapLen : 0;
+    pCfg->uCapNext = (pVirtio->fMsiSupport || pVirtio->pDevSpecificCfg) ? CFGADDR2IDX(pCfg) + pCfg->uCapLen : 0;
     pCfg->uBar     = 0;
     pCfg->uOffset  = 0;
@@ -1199 +1203 @@
         pCfg->uCapVndr = VIRTIO_PCI_CAP_ID_VENDOR;
         pCfg->uCapLen  = sizeof(VIRTIO_PCI_CAP_T);
-        pCfg->uCapNext = fMsiSupport ? CFGADDR2IDX(pCfg) + pCfg->uCapLen : 0;
+        pCfg->uCapNext = pVirtio->fMsiSupport ? CFGADDR2IDX(pCfg) + pCfg->uCapLen : 0;
         pCfg->uBar     = VIRTIO_REGION_PCI_CAP;
         pCfg->uOffset  = pVirtio->pIsrCap->uOffset + pVirtio->pIsrCap->uLength;
@@ -1208 +1212 @@
     }
 
-    /* Set offset to first capability and enable PCI dev capabilities */
-    PDMPciDevSetCapabilityList(pPciDev, 0x40);
-    PDMPciDevSetStatus(pPciDev,         VBOX_PCI_STATUS_CAP_LIST);
-
-    if (fMsiSupport)
+    if (pVirtio->fMsiSupport)
     {
         PDMMSIREG aMsiReg;
@@ -1218 +1218 @@
         aMsiReg.iMsixCapOffset  = pCfg->uCapNext;
         aMsiReg.iMsixNextOffset = 0;
-        aMsiReg.iMsixBar        = 0;
-        aMsiReg.cMsixVectors    = 1;
+        aMsiReg.iMsixBar        = VIRTIO_REGION_MSIX_CAP;
+        aMsiReg.cMsixVectors    = g_DeviceVirtioSCSI.cMaxMsixVectors;
         rc = PDMDevHlpPCIRegisterMsi(pDevIns, &aMsiReg); /* see MsixR3init() */
-        if (RT_FAILURE (rc))
-            /* The following is moot, we need to flag no MSI-X support */
-            PDMPciDevSetCapabilityList(pPciDev, 0x40);
-    }
+        if (RT_FAILURE(rc))
+        {
+            /* See PDMDevHlp.cpp:pdmR3DevHlp_PCIRegisterMsi */
+            Log(("Failed to configure MSI-X (%Rrc). Reverting to INTx\n"));
+            pVirtio->fMsiSupport = false;
+        }
+        else
+            Log(("Using MSI-X for guest driver notification\n"));
+    }
+    else
+        Log(("MSI-X not available for VBox, using INTx notification\n"));
+
+
+    /* Set offset to first capability and enable PCI dev capabilities */
+    PDMPciDevSetCapabilityList(pPciDev, 0x40);
+    PDMPciDevSetStatus(pPciDev,         VBOX_PCI_STATUS_CAP_LIST);
 
     /* Linux drivers/virtio/virtio_pci_modern.c tries to map at least a page for the

trunk/src/VBox/Devices/VirtIO/Virtio_1_0.h

@@ -39 +39 @@
 #define VIRTIO_NOTIFY_OFFSET_MULTIPLIER     2                    /**< VirtIO Notify Cap. MMIO config param     */
 #define VIRTIO_REGION_PCI_CAP               2                    /**< BAR for VirtIO Cap. MMIO (impl specific) */
+#define VIRTIO_REGION_MSIX_CAP              0                    /**< Bar for MSI-X handling                   */
 
 #define VIRTIO_HEX_DUMP(logLevel, pv, cb, base, title) \
@@ -163 +164 @@
 /**
  * Allocate client context for client to work with VirtIO-provided with queue
- * As a side effect creates a buffer vector a client can get a pointer to
- * with a call to virtioQueueDescChain()
  *
  * @param  hVirtio   - Handle to VirtIO framework
@@ -211 +210 @@
  * The caller passes in a pointer to a scatter-gather buffer of virtual memory segments
  * and a pointer to the descriptor chain context originally derived from the pulled
- * queue entry, and this function will put write the virtual memory s/g buffer into the
+ * queue entry, and this function will write the virtual memory s/g buffer into the
  * guest's physical memory free the descriptor chain. The caller handles the freeing
  * (as needed) of the virtual memory buffer.

trunk/src/VBox/Devices/VirtIO/Virtio_1_0_impl.h

@@ -189 +189 @@
     uint8_t                   uPciCfgDataOff;
     uint8_t                   uISR;                              /**< Interrupt Status Register.                */
+    uint8_t                   fMsiSupport;
 
 } VIRTIOSTATE, *PVIRTIOSTATE;
@@ -520 +521 @@
 static void virtioResetQueue        (PVIRTIOSTATE pVirtio, uint16_t qIdx);
 static void virtioNotifyGuestDriver (PVIRTIOSTATE pVirtio, uint16_t qIdx, bool fForce);
-static int  virtioRaiseInterrupt    (PVIRTIOSTATE pVirtio, uint8_t uCause, bool fForce);
-static void virtioLowerInterrupt    (PVIRTIOSTATE pVirtio);
+static int  virtioKick(PVIRTIOSTATE pVirtio, uint8_t uCause, uint16_t uVec, bool fForce);
 static void virtioQueueNotified     (PVIRTIOSTATE pVirtio, uint16_t qidx, uint16_t uDescIdx);
 static void virtioGuestResetted     (PVIRTIOSTATE pVirtio);