diff options
| -rw-r--r-- | drivers/pci/bus.c | 53 |
1 files changed, 48 insertions, 5 deletions
diff --git a/drivers/pci/bus.c b/drivers/pci/bus.c index 7f0af0e9b82..172bf26e068 100644 --- a/drivers/pci/bus.c +++ b/drivers/pci/bus.c @@ -64,6 +64,49 @@ void pci_bus_remove_resources(struct pci_bus *bus) } } +/* + * Find the highest-address bus resource below the cursor "res". If the + * cursor is NULL, return the highest resource. + */ +static struct resource *pci_bus_find_resource_prev(struct pci_bus *bus, + unsigned int type, + struct resource *res) +{ + struct resource *r, *prev = NULL; + int i; + + pci_bus_for_each_resource(bus, r, i) { + if (!r) + continue; + + if ((r->flags & IORESOURCE_TYPE_BITS) != type) + continue; + + /* If this resource is at or past the cursor, skip it */ + if (res) { + if (r == res) + continue; + if (r->end > res->end) + continue; + if (r->end == res->end && r->start > res->start) + continue; + } + + if (!prev) + prev = r; + + /* + * A small resource is higher than a large one that ends at + * the same address. + */ + if (r->end > prev->end || + (r->end == prev->end && r->start > prev->start)) + prev = r; + } + + return prev; +} + /** * pci_bus_alloc_resource - allocate a resource from a parent bus * @bus: PCI bus @@ -89,9 +132,10 @@ pci_bus_alloc_resource(struct pci_bus *bus, struct resource *res, resource_size_t), void *alignf_data) { - int i, ret = -ENOMEM; + int ret = -ENOMEM; struct resource *r; resource_size_t max = -1; + unsigned int type = res->flags & IORESOURCE_TYPE_BITS; type_mask |= IORESOURCE_IO | IORESOURCE_MEM; @@ -99,10 +143,9 @@ pci_bus_alloc_resource(struct pci_bus *bus, struct resource *res, if (!(res->flags & IORESOURCE_MEM_64)) max = PCIBIOS_MAX_MEM_32; - pci_bus_for_each_resource(bus, r, i) { - if (!r) - continue; - + /* Look for space at highest addresses first */ + r = pci_bus_find_resource_prev(bus, type, NULL); + for ( ; r; r = pci_bus_find_resource_prev(bus, type, r)) { /* type_mask must match */ if ((res->flags ^ r->flags) & type_mask) continue; |