From de3ffa301142bf8802a7b0de17f9985acde5c223 Mon Sep 17 00:00:00 2001 From: Jon Derrick Date: Tue, 25 Sep 2018 12:39:06 -0600 Subject: PCI: Equalize hotplug memory and io for occupied and empty slots Currently, a hotplug bridge will be given hpmemsize additional memory and hpiosize additional io if available, in order to satisfy any future hotplug allocation requirements. These calculations don't consider the current memory/io size of the hotplug bridge/slot, so hotplug bridges/slots which have downstream devices will be allocated their current allocation in addition to the hpmemsize value. This makes for possibly undesirable results with a mix of unoccupied and occupied slots (ex, with hpmemsize=2M): 02:03.0 PCI bridge: <-- Occupied Memory behind bridge: d6200000-d64fffff [size=3M] 02:04.0 PCI bridge: <-- Unoccupied Memory behind bridge: d6500000-d66fffff [size=2M] This change considers the current allocation size when using the hpmemsize/hpiosize parameters to make the reservations predictable for the mix of unoccupied and occupied slots: 02:03.0 PCI bridge: <-- Occupied Memory behind bridge: d6200000-d63fffff [size=2M] 02:04.0 PCI bridge: <-- Unoccupied Memory behind bridge: d6400000-d65fffff [size=2M] Signed-off-by: Jon Derrick Signed-off-by: Bjorn Helgaas --- drivers/pci/setup-bus.c | 28 +++++++++++++++------------- 1 file changed, 15 insertions(+), 13 deletions(-) (limited to 'drivers/pci/setup-bus.c') diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c index 79b1824e83b4..ed960436df5e 100644 --- a/drivers/pci/setup-bus.c +++ b/drivers/pci/setup-bus.c @@ -811,6 +811,8 @@ static struct resource *find_free_bus_resource(struct pci_bus *bus, static resource_size_t calculate_iosize(resource_size_t size, resource_size_t min_size, resource_size_t size1, + resource_size_t add_size, + resource_size_t children_add_size, resource_size_t old_size, resource_size_t align) { @@ -823,15 +825,18 @@ static resource_size_t calculate_iosize(resource_size_t size, #if defined(CONFIG_ISA) || defined(CONFIG_EISA) size = (size & 0xff) + ((size & ~0xffUL) << 2); #endif - size = ALIGN(size + size1, align); + size = size + size1; if (size < old_size) size = old_size; + + size = ALIGN(max(size, add_size) + children_add_size, align); return size; } static resource_size_t calculate_memsize(resource_size_t size, resource_size_t min_size, - resource_size_t size1, + resource_size_t add_size, + resource_size_t children_add_size, resource_size_t old_size, resource_size_t align) { @@ -841,7 +846,8 @@ static resource_size_t calculate_memsize(resource_size_t size, old_size = 0; if (size < old_size) size = old_size; - size = ALIGN(size + size1, align); + + size = ALIGN(max(size, add_size) + children_add_size, align); return size; } @@ -930,12 +936,10 @@ static void pbus_size_io(struct pci_bus *bus, resource_size_t min_size, } } - size0 = calculate_iosize(size, min_size, size1, + size0 = calculate_iosize(size, min_size, size1, 0, 0, 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, + size1 = (!realloc_head || (realloc_head && !add_size && !children_add_size)) ? size0 : + calculate_iosize(size, min_size, size1, add_size, children_add_size, resource_size(b_res), min_align); if (!size0 && !size1) { if (b_res->start || b_res->end) @@ -1079,12 +1083,10 @@ static int pbus_size_mem(struct pci_bus *bus, unsigned long mask, min_align = calculate_mem_align(aligns, max_order); min_align = max(min_align, window_alignment(bus, b_res->flags)); - size0 = calculate_memsize(size, min_size, 0, resource_size(b_res), min_align); + size0 = calculate_memsize(size, min_size, 0, 0, resource_size(b_res), min_align); add_align = max(min_align, add_align); - if (children_add_size > add_size) - add_size = children_add_size; - size1 = (!realloc_head || (realloc_head && !add_size)) ? size0 : - calculate_memsize(size, min_size, add_size, + size1 = (!realloc_head || (realloc_head && !add_size && !children_add_size)) ? size0 : + calculate_memsize(size, min_size, add_size, children_add_size, resource_size(b_res), add_align); if (!size0 && !size1) { if (b_res->start || b_res->end) -- cgit v1.2.3