[PATCH 6/9] pci: don't shrink bridge resources

From: Yinghai Lu
Date: Wed Nov 25 2009 - 15:01:08 EST



when we are clearing leaf bridge resource and try to get big one, we could shrink the bridge if
there is no resource under it.

let check with old resource size and make sure we are trying to get big one.

Signed-off-by: Yinghai Lu <yinghai@xxxxxxxxxx>

---
drivers/pci/setup-bus.c | 22 ++++++++++++----------
1 file changed, 12 insertions(+), 10 deletions(-)

Index: linux-2.6/drivers/pci/setup-bus.c
===================================================================
--- linux-2.6.orig/drivers/pci/setup-bus.c
+++ linux-2.6/drivers/pci/setup-bus.c
@@ -390,7 +390,7 @@ static void pbus_size_io(struct pci_bus
{
struct pci_dev *dev;
struct resource *b_res = find_free_bus_resource(bus, IORESOURCE_IO);
- unsigned long size = 0, size1 = 0;
+ unsigned long size = 0, size1 = 0, old_size;

if (!b_res)
return;
@@ -415,17 +415,18 @@ static void pbus_size_io(struct pci_bus
}
if (size < min_size)
size = min_size;
+ old_size = resource_size(b_res);
+ if (old_size == 1)
+ old_size = 0;
/* To be fixed in 2.5: we should have sort of HAVE_ISA
flag in the struct pci_bus. */
#if defined(CONFIG_ISA) || defined(CONFIG_EISA)
size = (size & 0xff) + ((size & ~0xffUL) << 2);
#endif
size = ALIGN(size + size1, 4096);
+ if (size < old_size)
+ size = old_size;
if (!size) {
- if (b_res->start || b_res->end)
- dev_info(&bus->self->dev, "disabling bridge window "
- "%pR to [bus %02x-%02x] (unused)\n", b_res,
- bus->secondary, bus->subordinate);
b_res->flags = 0;
return;
}
@@ -441,7 +442,7 @@ static int pbus_size_mem(struct pci_bus
unsigned long type, resource_size_t min_size)
{
struct pci_dev *dev;
- resource_size_t min_align, align, size;
+ resource_size_t min_align, align, size, old_size;
resource_size_t aligns[12]; /* Alignments from 1Mb to 2Gb */
int order, max_order;
struct resource *b_res = find_free_bus_resource(bus, type);
@@ -491,6 +492,11 @@ static int pbus_size_mem(struct pci_bus
}
if (size < min_size)
size = min_size;
+ old_size = resource_size(b_res);
+ if (old_size == 1)
+ old_size = 0;
+ if (size < old_size)
+ size = old_size;

align = 0;
min_align = 0;
@@ -507,10 +513,6 @@ static int pbus_size_mem(struct pci_bus
}
size = ALIGN(size, min_align);
if (!size) {
- if (b_res->start || b_res->end)
- dev_info(&bus->self->dev, "disabling bridge window "
- "%pR to [bus %02x-%02x] (unused)\n", b_res,
- bus->secondary, bus->subordinate);
b_res->flags = 0;
return 1;
}

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/