PCI: add a PCI resource reallocation config option
Add a new config option, PCI_REALLOC_ENABLE_AUTO, which will
automatically try to re-allocate PCI resources if PCI_IOV support is
enabled and the SR-IOV resources are unassigned. Behavior can still be
controlled using the pci=realloc= parameter.
-v2: According to Jesse, adding one CONFIG option for distribution to
disable it or enable it.
-v3: update Kconfig text (jbarnes)
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
index e21e1c23..c9214a1 100644
--- a/drivers/pci/setup-bus.c
+++ b/drivers/pci/setup-bus.c
@@ -1294,6 +1294,31 @@
return pci_realloc_enable >= user_enabled;
}
+static void __init pci_realloc_detect(void)
+{
+#if defined(CONFIG_PCI_IOV) && defined(CONFIG_PCI_REALLOC_ENABLE_AUTO)
+ struct pci_dev *dev = NULL;
+
+ if (pci_realloc_enable != undefined)
+ return;
+
+ for_each_pci_dev(dev) {
+ int i;
+
+ for (i = PCI_IOV_RESOURCES; i <= PCI_IOV_RESOURCE_END; i++) {
+ struct resource *r = &dev->resource[i];
+
+ /* Not assigned, or rejected by kernel ? */
+ if (r->flags && !r->start) {
+ pci_realloc_enable = auto_enabled;
+
+ return;
+ }
+ }
+ }
+#endif
+}
+
/*
* first try will not touch pci bridge res
* second and later try will clear small leaf bridge res
@@ -1315,6 +1340,7 @@
int pci_try_num = 1;
/* don't realloc if asked to do so */
+ pci_realloc_detect();
if (pci_realloc_enabled()) {
int max_depth = pci_get_max_depth();
@@ -1349,6 +1375,8 @@
if (tried_times >= pci_try_num) {
if (pci_realloc_enable == undefined)
printk(KERN_INFO "Some PCI device resources are unassigned, try booting with pci=realloc\n");
+ else if (pci_realloc_enable == auto_enabled)
+ printk(KERN_INFO "Automatically enabled pci realloc, if you have problem, try booting with pci=realloc=off\n");
free_list(&fail_head);
goto enable_and_dump;