4.19-stable review patch. If anyone has any objections, please let me know.
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From: Jon Derrick jonathan.derrick@intel.com
[ Upstream commit de3ffa301142bf8802a7b0de17f9985acde5c223 ]
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 jonathan.derrick@intel.com Signed-off-by: Bjorn Helgaas bhelgaas@google.com Stable-dep-of: 903534fa7d30 ("PCI: Fix resource double counting on remove & rescan") Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/pci/setup-bus.c | 28 +++++++++++++++------------- 1 file changed, 15 insertions(+), 13 deletions(-)
diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c index 87c8190de622f..7f58360b42b7e 100644 --- a/drivers/pci/setup-bus.c +++ b/drivers/pci/setup-bus.c @@ -774,6 +774,8 @@ 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) { @@ -786,15 +788,18 @@ 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) { @@ -804,7 +809,8 @@ 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; }
@@ -893,12 +899,10 @@ 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) @@ -1042,12 +1046,10 @@ 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)