@@ -46,6 +46,30 @@ static inline void pci_iov_set_numvfs(struct pci_dev *dev, int nr_virtfn)
pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_STRIDE, &iov->stride);
}
+/**
+ * Per SRIOV SPEC section 3.3.10 and 3.3.11, VF Stride and VF offset may
+ * change when NumVFs changes. Which will affect the bus range for VFs.
+ *
+ * This function iterate on all valide NumVFs and calculate the maximum bus
+ * range for VFs.
+ */
+static inline void pci_iov_max_bus_range(struct pci_dev *dev)
+{
+ struct pci_sriov *iov = dev->sriov;
+ int total = iov->total_VFs;
+ u8 max = 0;
+ u8 busnr;
+
+ for ( ; total >= 0; total--) {
+ pci_iov_set_numvfs(dev, total);
+ busnr = virtfn_bus(dev, iov->total_VFs - 1);
+ if (busnr > max)
+ max = busnr;
+ }
+
+ iov->max_bus_range = max;
+}
+
static struct pci_bus *virtfn_add_bus(struct pci_bus *bus, int busnr)
{
struct pci_bus *child;
@@ -415,6 +439,7 @@ found:
dev->sriov = iov;
dev->is_physfn = 1;
+ pci_iov_max_bus_range(dev);
return 0;
@@ -550,15 +575,13 @@ void pci_restore_iov_state(struct pci_dev *dev)
int pci_iov_bus_range(struct pci_bus *bus)
{
int max = 0;
- u8 busnr;
struct pci_dev *dev;
list_for_each_entry(dev, &bus->devices, bus_list) {
if (!dev->is_physfn)
continue;
- busnr = virtfn_bus(dev, dev->sriov->total_VFs - 1);
- if (busnr > max)
- max = busnr;
+ if (dev->sriov->max_bus_range > max)
+ max = dev->sriov->max_bus_range;
}
return max ? max - bus->number : 0;
@@ -236,6 +236,7 @@ struct pci_sriov {
u16 stride; /* following VF stride */
u32 pgsz; /* page size for BAR alignment */
u8 link; /* Function Dependency Link */
+ u8 max_bus_range; /* Maximum bus range a VF could sit*/
u16 driver_max_VFs; /* max num VFs driver supports */
struct pci_dev *dev; /* lowest numbered PF */
struct pci_dev *self; /* this PF */
Per SRIOV SPEC section 3.3.10 and 3.3.11, VF Stride and VF Offset may change when NumVFs changes. This will affect the bus range for VFs. This patch iterates on each possible NumVFs and calculate the maximum bus range for VFs. Signed-off-by: Wei Yang <weiyang@linux.vnet.ibm.com> --- drivers/pci/iov.c | 31 +++++++++++++++++++++++++++---- drivers/pci/pci.h | 1 + 2 files changed, 28 insertions(+), 4 deletions(-)