Re: [PATCH v2 09/20] vfio/pci: Make vfio_pci_relocate_msix() and vfio_msix_early_setup() return a bool

[Cédric Le Goater]

On 5/22/24 06:40, Zhenzhong Duan wrote:

Since vfio_pci_relocate_msix() and vfio_msix_early_setup() takes
an 'Error **' argument, best practices suggest to return a bool.
See the qapi/error.h Rules section.

By this chance, pass errp directly to vfio_msix_early_setup() to avoid
calling error_propagate().

Signed-off-by: Zhenzhong Duan <zhenzhong.d...@intel.com>

Reviewed-by: Cédric Le Goater <c...@redhat.com>

Thanks,

C.

---
  hw/vfio/pci.c | 33 ++++++++++++++++-----------------
  1 file changed, 16 insertions(+), 17 deletions(-)

diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
index 12fb534d79..4fb5fd0c9f 100644
--- a/hw/vfio/pci.c
+++ b/hw/vfio/pci.c
@@ -1450,13 +1450,13 @@ static void vfio_pci_fixup_msix_region(VFIOPCIDevice 
*vdev)
      }
  }

-static void vfio_pci_relocate_msix(VFIOPCIDevice *vdev, Error **errp)

+static bool vfio_pci_relocate_msix(VFIOPCIDevice *vdev, Error **errp)
  {
      int target_bar = -1;
      size_t msix_sz;

if (!vdev->msix || vdev->msix_relo == OFF_AUTOPCIBAR_OFF) {

-        return;
+        return true;
      }

/* The actual minimum size of MSI-X structures */

@@ -1479,7 +1479,7 @@ static void vfio_pci_relocate_msix(VFIOPCIDevice *vdev, 
Error **errp)
          if (target_bar < 0) {
              error_setg(errp, "No automatic MSI-X relocation available for "
                         "device %04x:%04x", vdev->vendor_id, vdev->device_id);
-            return;
+            return false;
          }
      } else {
          target_bar = (int)(vdev->msix_relo - OFF_AUTOPCIBAR_BAR0);
@@ -1489,7 +1489,7 @@ static void vfio_pci_relocate_msix(VFIOPCIDevice *vdev, 
Error **errp)
      if (vdev->bars[target_bar].ioport) {
          error_setg(errp, "Invalid MSI-X relocation BAR %d, "
                     "I/O port BAR", target_bar);
-        return;
+        return false;
      }

/* Cannot use a BAR in the "shadow" of a 64-bit BAR */

@@ -1497,7 +1497,7 @@ static void vfio_pci_relocate_msix(VFIOPCIDevice *vdev, 
Error **errp)
           target_bar > 0 && vdev->bars[target_bar - 1].mem64) {
          error_setg(errp, "Invalid MSI-X relocation BAR %d, "
                     "consumed by 64-bit BAR %d", target_bar, target_bar - 1);
-        return;
+        return false;
      }

/* 2GB max size for 32-bit BARs, cannot double if already > 1G */

@@ -1505,7 +1505,7 @@ static void vfio_pci_relocate_msix(VFIOPCIDevice *vdev, 
Error **errp)
          !vdev->bars[target_bar].mem64) {
          error_setg(errp, "Invalid MSI-X relocation BAR %d, "
                     "no space to extend 32-bit BAR", target_bar);
-        return;
+        return false;
      }

/*

@@ -1540,6 +1540,7 @@ static void vfio_pci_relocate_msix(VFIOPCIDevice *vdev, 
Error **errp)

trace_vfio_msix_relo(vdev->vbasedev.name,

                           vdev->msix->table_bar, vdev->msix->table_offset);
+    return true;
  }

/*

@@ -1550,7 +1551,7 @@ static void vfio_pci_relocate_msix(VFIOPCIDevice *vdev, 
Error **errp)
   * need to first look for where the MSI-X table lives.  So we
   * unfortunately split MSI-X setup across two functions.
   */
-static void vfio_msix_early_setup(VFIOPCIDevice *vdev, Error **errp)
+static bool vfio_msix_early_setup(VFIOPCIDevice *vdev, Error **errp)
  {
      uint8_t pos;
      uint16_t ctrl;
@@ -1562,25 +1563,25 @@ static void vfio_msix_early_setup(VFIOPCIDevice *vdev, 
Error **errp)

pos = pci_find_capability(&vdev->pdev, PCI_CAP_ID_MSIX);

      if (!pos) {
-        return;
+        return true;
      }

if (pread(fd, &ctrl, sizeof(ctrl),

                vdev->config_offset + pos + PCI_MSIX_FLAGS) != sizeof(ctrl)) {
          error_setg_errno(errp, errno, "failed to read PCI MSIX FLAGS");
-        return;
+        return false;
      }

if (pread(fd, &table, sizeof(table),

                vdev->config_offset + pos + PCI_MSIX_TABLE) != sizeof(table)) {
          error_setg_errno(errp, errno, "failed to read PCI MSIX TABLE");
-        return;
+        return false;
      }

if (pread(fd, &pba, sizeof(pba),

                vdev->config_offset + pos + PCI_MSIX_PBA) != sizeof(pba)) {
          error_setg_errno(errp, errno, "failed to read PCI MSIX PBA");
-        return;
+        return false;
      }

ctrl = le16_to_cpu(ctrl);

@@ -1598,7 +1599,7 @@ static void vfio_msix_early_setup(VFIOPCIDevice *vdev, 
Error **errp)
      if (ret < 0) {
          error_setg_errno(errp, -ret, "failed to get MSI-X irq info");
          g_free(msix);
-        return;
+        return false;
      }

msix->noresize = !!(irq_info.flags & VFIO_IRQ_INFO_NORESIZE);

@@ -1630,7 +1631,7 @@ static void vfio_msix_early_setup(VFIOPCIDevice *vdev, 
Error **errp)
              error_setg(errp, "hardware reports invalid configuration, "
                         "MSIX PBA outside of specified BAR");
              g_free(msix);
-            return;
+            return false;
          }
      }

@@ -1641,7 +1642,7 @@ static void vfio_msix_early_setup(VFIOPCIDevice *vdev, Error **errp) vfio_pci_fixup_msix_region(vdev); - vfio_pci_relocate_msix(vdev, errp);

+    return vfio_pci_relocate_msix(vdev, errp);
  }

static int vfio_msix_setup(VFIOPCIDevice *vdev, int pos, Error **errp)

@@ -3130,9 +3131,7 @@ static void vfio_realize(PCIDevice *pdev, Error **errp)

vfio_bars_prepare(vdev); - vfio_msix_early_setup(vdev, &err);

-    if (err) {
-        error_propagate(errp, err);
+    if (!vfio_msix_early_setup(vdev, errp)) {
          goto error;
      }