[PATCH v10 3/7] PCI: reserve bus range for SR-IOV device

Yu Zhao
2009-02-20T06:55:16Z

Signed-off-by: Yu Zhao <yu.zhao@intel.com>
---
drivers/pci/iov.c | 34 ++++++++++++++++++++++++++++++++++
drivers/pci/pci.h | 5 +++++
drivers/pci/probe.c | 3 +++
3 files changed, 42 insertions(+), 0 deletions(-)

diff --git a/drivers/pci/iov.c b/drivers/pci/iov.c
index 3bca8f8..0b80437 100644
--- a/drivers/pci/iov.c
+++ b/drivers/pci/iov.c
@@ -14,6 +14,16 @@
#include "pci.h"

+static inline void virtfn_bdf(struct pci_dev *dev, int id, u8 *busnr, u8 *devfn)
+{
+ u16 bdf;
+
+ bdf = (dev->bus->number << 8) + dev->devfn +
+ dev->sriov->offset + dev->sriov->stride * id;
+ *busnr = bdf >> 8;
+ *devfn = bdf & 0xff;
+}
+
static int sriov_init(struct pci_dev *dev, int pos)
{
int i;
@@ -208,3 +218,27 @@ void pci_restore_iov_state(struct pci_dev *dev)
if (dev->sriov)
sriov_restore_state(dev);
}
+
+/**
+ * pci_iov_bus_range - find bus range used by Virtual Function
+ * @bus: the PCI bus
+ *
+ * Returns max number of buses (exclude current one) used by Virtual
+ * Functions.
+ */
+int pci_iov_bus_range(struct pci_bus *bus)
+{
+ int max = 0;
+ u8 busnr, devfn;
+ struct pci_dev *dev;
+
+ list_for_each_entry(dev, &bus->devices, bus_list) {
+ if (!dev->sriov)
+ continue;
+ virtfn_bdf(dev, dev->sriov->total - 1, &busnr, &devfn);
+ if (busnr > max)
+ max = busnr;
+ }
+
+ return max ? max - bus->number : 0;
+}
diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index b24c9e2..2cf32f5 100644
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -217,6 +217,7 @@ extern void pci_iov_release(struct pci_dev *dev);
extern int pci_iov_resource_bar(struct pci_dev *dev, int resno,
enum pci_bar_type *type);
extern void pci_restore_iov_state(struct pci_dev *dev);
+extern int pci_iov_bus_range(struct pci_bus *bus);
#else
static inline int pci_iov_init(struct pci_dev *dev)
{
@@ -234,6 +235,10 @@ static inline int pci_iov_resource_bar(struct pci_dev *dev, int resno,
static inline void pci_restore_iov_state(struct pci_dev *dev)
{
}
+static inline int pci_iov_bus_range(struct pci_bus *bus)
+{
+ return 0;
+}
#endif /* CONFIG_PCI_IOV */

#endif /* DRIVERS_PCI_H */
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 03b6f29..4c8abd0 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -1078,6 +1078,9 @@ unsigned int __devinit pci_scan_child_bus(struct pci_bus *bus)
for (devfn = 0; devfn < 0x100; devfn += 8)
pci_scan_slot(bus, devfn);

+ /* Reserve buses for SR-IOV capability. */
+ max += pci_iov_bus_range(bus);
+
/*
* After performing arch-dependent fixup of the bus, look behind
* all PCI-to-PCI bridges on this bus.
--
1.6.1