From 013220b686022a2e4ddb6a3d50af467275d25070 Mon Sep 17 00:00:00 2001
From: Kunkun Jiang <jiangkunkun@huawei.com>
Date: Fri, 18 Nov 2022 15:22:37 +0800
Subject: [PATCH 18/36] Revert "vfio/pci: Implement the DMA fault handler"

This reverts commit d33cc7eccb68c6a1488804c94ff5c1197ee0fc6e.

Signed-off-by: Kunkun Jiang <jiangkunkun@huawei.com>
---
 hw/vfio/pci.c | 50 --------------------------------------------------
 hw/vfio/pci.h |  1 -
 2 files changed, 51 deletions(-)

diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
index c54e62fe8f..76bc9d3506 100644
--- a/hw/vfio/pci.c
+++ b/hw/vfio/pci.c
@@ -2953,60 +2953,10 @@ static PCIPASIDOps vfio_pci_pasid_ops = {
 static void vfio_dma_fault_notifier_handler(void *opaque)
 {
     VFIOPCIExtIRQ *ext_irq = opaque;
-    VFIOPCIDevice *vdev = ext_irq->vdev;
-    PCIDevice *pdev = &vdev->pdev;
-    AddressSpace *as = pci_device_iommu_address_space(pdev);
-    IOMMUMemoryRegion *iommu_mr = IOMMU_MEMORY_REGION(as->root);
-    struct vfio_region_dma_fault header;
-    struct iommu_fault *queue;
-    char *queue_buffer = NULL;
-    ssize_t bytes;
 
     if (!event_notifier_test_and_clear(&ext_irq->notifier)) {
         return;
     }
-
-    bytes = pread(vdev->vbasedev.fd, &header, sizeof(header),
-                  vdev->dma_fault_region.fd_offset);
-    if (bytes != sizeof(header)) {
-        error_report("%s unable to read the fault region header (0x%lx)",
-                     __func__, bytes);
-        return;
-    }
-
-    /* Normally the fault queue is mmapped */
-    queue = (struct iommu_fault *)vdev->dma_fault_region.mmaps[0].mmap;
-    if (!queue) {
-        size_t queue_size = header.nb_entries * header.entry_size;
-
-        error_report("%s: fault queue not mmapped: slower fault handling",
-                     vdev->vbasedev.name);
-
-        queue_buffer = g_malloc(queue_size);
-        bytes =  pread(vdev->vbasedev.fd, queue_buffer, queue_size,
-                       vdev->dma_fault_region.fd_offset + header.offset);
-        if (bytes != queue_size) {
-            error_report("%s unable to read the fault queue (0x%lx)",
-                         __func__, bytes);
-            return;
-        }
-
-        queue = (struct iommu_fault *)queue_buffer;
-    }
-
-    while (vdev->fault_tail_index != header.head) {
-        memory_region_inject_faults(iommu_mr, 1,
-                                    &queue[vdev->fault_tail_index]);
-        vdev->fault_tail_index =
-            (vdev->fault_tail_index + 1) % header.nb_entries;
-    }
-    bytes = pwrite(vdev->vbasedev.fd, &vdev->fault_tail_index, 4,
-                   vdev->dma_fault_region.fd_offset);
-    if (bytes != 4) {
-        error_report("%s unable to write the fault region tail index (0x%lx)",
-                     __func__, bytes);
-    }
-    g_free(queue_buffer);
 }
 
 static int vfio_register_ext_irq_handler(VFIOPCIDevice *vdev,
diff --git a/hw/vfio/pci.h b/hw/vfio/pci.h
index 03ac8919ef..eef91065f1 100644
--- a/hw/vfio/pci.h
+++ b/hw/vfio/pci.h
@@ -146,7 +146,6 @@ struct VFIOPCIDevice {
     EventNotifier req_notifier;
     VFIOPCIExtIRQ *ext_irqs;
     VFIORegion dma_fault_region;
-    uint32_t fault_tail_index;
     int (*resetfn)(struct VFIOPCIDevice *);
     uint32_t vendor_id;
     uint32_t device_id;
-- 
2.27.0