[PATCH v2 25/49] PCI: Don't add too much optional size for hotplug bridge io

Yinghai Lu
2015-07-14T22:52:33Z

Same as patch for mmio (PCI: Don't add too much optional size for hotplug
bridge mmio), and this one is addressing io port.

It will compare must+optional with min_sum_size to get smaller
optional size.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
drivers/pci/setup-bus.c | 26 ++++++++++++++++----------
1 file changed, 16 insertions(+), 10 deletions(-)

diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
index 8999ead..de55e07 100644
--- a/drivers/pci/setup-bus.c
+++ b/drivers/pci/setup-bus.c
@@ -1189,7 +1189,6 @@ static resource_size_t window_alignment(struct pci_bus *bus,
*
* @bus : the bus
* @min_size : the minimum io window that must to be allocated
- * @add_size : additional optional io window
* @realloc_head : track the additional io window on this list
*
* Sizing the IO windows of the PCI-PCI bridge is trivial,
@@ -1198,9 +1197,11 @@ static resource_size_t window_alignment(struct pci_bus *bus,
* We must be careful with the ISA aliasing though.
*/
static void pbus_size_io(struct pci_bus *bus, resource_size_t min_size,
- resource_size_t add_size, struct list_head *realloc_head)
+ struct list_head *realloc_head)
{
struct pci_dev *dev;
+ resource_size_t min_sum_size = 0;
+ resource_size_t sum_add_size;
struct resource *b_res = find_free_bus_resource(bus, IORESOURCE_IO,
IORESOURCE_IO);
resource_size_t size = 0, size0 = 0, size1 = 0;
@@ -1210,6 +1211,11 @@ static void pbus_size_io(struct pci_bus *bus, resource_size_t min_size,
if (!b_res)
return;

+ if (realloc_head) {
+ min_sum_size = min_size;
+ min_size = 0;
+ }
+
min_align = window_alignment(bus, IORESOURCE_IO);
list_for_each_entry(dev, &bus->devices, bus_list) {
int i;
@@ -1239,10 +1245,11 @@ static void pbus_size_io(struct pci_bus *bus, resource_size_t min_size,

size0 = calculate_iosize(size, min_size, size1,
resource_size(b_res), min_align);
- if (children_add_size > add_size)
- add_size = children_add_size;
- size1 = (!realloc_head || (realloc_head && !add_size)) ? size0 :
- calculate_iosize(size, min_size, add_size + size1,
+ sum_add_size = children_add_size + size + size1;
+ if (sum_add_size < min_sum_size)
+ sum_add_size = min_sum_size;
+ size1 = !realloc_head ? size0 :
+ calculate_iosize(size, min_size, sum_add_size - size,
resource_size(b_res), min_align);
if (!size0 && !size1) {
if (b_res->start || b_res->end)
@@ -1783,7 +1790,7 @@ void __pci_bus_size_bridges(struct pci_bus *bus, struct list_head *realloc_head)
{
struct pci_dev *dev;
unsigned long mask, prefmask, type2 = 0, type3 = 0;
- resource_size_t min_mem_size = 0, additional_io_size = 0;
+ resource_size_t min_mem_size = 0, min_io_size = 0;
struct resource *b_res;
int ret;

@@ -1816,13 +1823,12 @@ void __pci_bus_size_bridges(struct pci_bus *bus, struct list_head *realloc_head)
case PCI_CLASS_BRIDGE_PCI:
pci_bridge_check_ranges(bus);
if (bus->self->is_hotplug_bridge) {
- additional_io_size = pci_hotplug_io_size;
+ min_io_size = pci_hotplug_io_size;
min_mem_size = pci_hotplug_mem_size;
}
/* Fall through */
default:
- pbus_size_io(bus, realloc_head ? 0 : additional_io_size,
- additional_io_size, realloc_head);
+ pbus_size_io(bus, min_io_size, realloc_head);

/*
* If there's a 64-bit prefetchable MMIO window, compute
--
1.8.4.5