Kernel provides the guidance of dynamic MSI-X allocation support of
passthrough device, by clearing the VFIO_IRQ_INFO_NORESIZE flag to
guide user space.
Fetch the flags from host to determine if dynamic MSI-X allocation is
supported.
Originally-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Jing Liu <jing2.liu@intel.com>
---
Changes since RFC v1:
- Filter the dynamic MSI-X allocation flag and store as a bool type.
(Alex)
- Move the detection to vfio_msix_early_setup(). (Alex)
- Report error of getting irq info and remove the trace of failure
case. (Alex, Cédric)
---
hw/vfio/pci.c | 15 +++++++++++++--
hw/vfio/pci.h | 1 +
hw/vfio/trace-events | 2 +-
3 files changed, 15 insertions(+), 3 deletions(-)
diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
index a205c6b1130f..8a3b34f3c196 100644
--- a/hw/vfio/pci.c
+++ b/hw/vfio/pci.c
@@ -1493,7 +1493,9 @@ static void vfio_msix_early_setup(VFIOPCIDevice *vdev,
Error **errp)
uint8_t pos;
uint16_t ctrl;
uint32_t table, pba;
- int fd = vdev->vbasedev.fd;
+ int ret, fd = vdev->vbasedev.fd;
+ struct vfio_irq_info irq_info = { .argsz = sizeof(irq_info),
+ .index = VFIO_PCI_MSIX_IRQ_INDEX };
VFIOMSIXInfo *msix;
pos = pci_find_capability(&vdev->pdev, PCI_CAP_ID_MSIX);
@@ -1530,6 +1532,14 @@ static void vfio_msix_early_setup(VFIOPCIDevice *vdev,
Error **errp)
msix->pba_offset = pba & ~PCI_MSIX_FLAGS_BIRMASK;
msix->entries = (ctrl & PCI_MSIX_FLAGS_QSIZE) + 1;
+ ret = ioctl(vdev->vbasedev.fd, VFIO_DEVICE_GET_IRQ_INFO, &irq_info);
+ if (ret < 0) {
+ error_setg_errno(errp, -ret, "failed to get MSI-X irq info");
+ return;
+ }
+
+ msix->noresize = !!(irq_info.flags & VFIO_IRQ_INFO_NORESIZE);
+
/*
* Test the size of the pba_offset variable and catch if it extends
outside
* of the specified BAR. If it is the case, we need to apply a hardware
@@ -1562,7 +1572,8 @@ static void vfio_msix_early_setup(VFIOPCIDevice *vdev,
Error **errp)
}
trace_vfio_msix_early_setup(vdev->vbasedev.name, pos, msix->table_bar,
- msix->table_offset, msix->entries);
+ msix->table_offset, msix->entries,
+ msix->noresize);
vdev->msix = msix;
vfio_pci_fixup_msix_region(vdev);
diff --git a/hw/vfio/pci.h b/hw/vfio/pci.h
index a2771b9ff3cc..0717574d79e9 100644
--- a/hw/vfio/pci.h
+++ b/hw/vfio/pci.h
@@ -113,6 +113,7 @@ typedef struct VFIOMSIXInfo {
uint32_t table_offset;
uint32_t pba_offset;
unsigned long *pending;
+ bool noresize;
} VFIOMSIXInfo;
#define TYPE_VFIO_PCI "vfio-pci"
diff --git a/hw/vfio/trace-events b/hw/vfio/trace-events
index ee7509e68e4f..6de5d9ba8e46 100644
--- a/hw/vfio/trace-events
+++ b/hw/vfio/trace-events
@@ -27,7 +27,7 @@ vfio_vga_read(uint64_t addr, int size, uint64_t data) "
(0x%"PRIx64", %d) = 0x%"
vfio_pci_read_config(const char *name, int addr, int len, int val) " (%s, @0x%x,
len=0x%x) 0x%x"
vfio_pci_write_config(const char *name, int addr, int val, int len) " (%s, @0x%x,
0x%x, len=0x%x)"
vfio_msi_setup(const char *name, int pos) "%s PCI MSI CAP @0x%x"
-vfio_msix_early_setup(const char *name, int pos, int table_bar, int offset, int entries)
"%s PCI MSI-X CAP @0x%x, BAR %d, offset 0x%x, entries %d"
+vfio_msix_early_setup(const char *name, int pos, int table_bar, int offset, int entries,
bool noresize) "%s PCI MSI-X CAP @0x%x, BAR %d, offset 0x%x, entries %d, noresize
%d"
vfio_check_pcie_flr(const char *name) "%s Supports FLR via PCIe cap"
vfio_check_pm_reset(const char *name) "%s Supports PM reset"
vfio_check_af_flr(const char *name) "%s Supports FLR via AF cap"