linux/drivers/pci
Ram Pai c8adf9a3e8 PCI: pre-allocate additional resources to devices only after successful allocation of essential resources.
Linux tries to pre-allocate minimal resources to hotplug bridges. This
works fine as long as there are enough resources  to satisfy all other
genuine resource requirements. However if enough resources are not
available to satisfy any of these nice-to-have pre-allocations, the
resource-allocator reports errors and returns failure.

This patch distinguishes between must-have resource from nice-to-have
resource.  Any failure to allocate nice-to-have resources are ignored.

This behavior can be particularly useful to trigger automatic
reallocation when the OS discovers genuine allocation-conflicts or
genuine unallocated-requests caused by buggy allocation behavior of the
native BIOS/uEFI.

https://bugzilla.kernel.org/show_bug.cgi?id=15960 captures the
movitation behind the patch. This patch is verified to resolve the above
bug.

    changelog v2:  o  fixed a bug where pci_assign_resource() was called on a
    		  resource of zero resource size.

    changelog v3:  addressed Bjorn's comment
    	       o  "Please don't indent and right-justify the changelog".
    	       o  removed add_size from struct resource.  The additional
    		  size is now tracked using a linked list.

    changelog v4:  o moved freeing up of elements in head list from
    		assign_requested_resources_sorted() to
    		__assign_resources_sorted().
    	       o removed a wrong reference to 'add_size' in
    			pbus_size_mem().
    	       o some code optimizations in adjust_resources_sorted()
    			and assign_requested_resources_sorted()

    changelog v5:  o moved freeing up of elements in head list from
    		assign_requested_resources_sorted() to
    		__assign_resources_sorted().
    	       o removed a wrong reference to 'add_size' in
    			pbus_size_mem().
    	       o some code optimizations in adjust_resources_sorted()
    			and assign_requested_resources_sorted()

    changelog v5:  o factored out common code and made them into
		separate independent patches
    	       o added comments in kdoc format
	       o added a BUG_ON in pci_assign_unassigned_resources()
		 to catch for memory leak.

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2011-03-04 10:46:47 -08:00
..
hotplug PCI hotplug: acpiphp: set current_state to D0 in register_slot 2011-03-04 10:42:22 -08:00
pcie PCI: aer-inject: Override PCIe AER Mask Registers 2011-03-04 10:41:02 -08:00
.gitignore
Kconfig PCI: Export ACPI _DSM provided firmware instance number and string name to sysfs 2011-03-04 10:41:56 -08:00
Makefile PCI: Export ACPI _DSM provided firmware instance number and string name to sysfs 2011-03-04 10:41:56 -08:00
access.c PCI: output FW warning in pci_read/write_vpd 2010-05-18 15:00:25 -07:00
bus.c Revert "PCI: allocate bus resources from the top down" 2010-12-17 10:00:54 -08:00
dmar.c x86, vt-d: Handle previous faults after enabling fault handling 2010-12-13 16:53:57 -08:00
hotplug-pci.c
hotplug.c
htirq.c ht: Convert to new irq_chip functions 2010-10-12 16:53:37 +02:00
intel-iommu.c Merge git://git.infradead.org/iommu-2.6 2010-09-27 12:25:10 -07:00
intr_remapping.c x86: Speed up the irq_remapped check in hot pathes 2010-10-12 16:53:42 +02:00
intr_remapping.h intr-remap: generic support for remapping HPET MSIs 2009-08-27 23:33:20 +02:00
ioapic.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
iov.c PCI: fix pci_resource_alignment prototype 2010-09-09 13:41:25 -07:00
iova.c intel-iommu: Remove superfluous iova_alloc_lock from IOVA code 2009-07-15 08:17:02 +01:00
irq.c PCI: struct device - replace bus_id with dev_name(), dev_set_name() 2009-01-07 11:12:23 -08:00
msi.c PCI: Add mask bit definition for MSI-X table 2010-12-23 12:53:08 -08:00
msi.h PCI: MSI: Move MSI-X entry definition to pci_regs.h 2010-12-23 12:53:07 -08:00
pci-acpi.c PCI/PM: Report wakeup events before resuming devices 2011-01-14 08:55:43 -08:00
pci-driver.c PCI: fix __pci_device_probe kernel-doc warning 2010-12-23 12:53:09 -08:00
pci-label.c PCI: Export ACPI _DSM provided firmware instance number and string name to sysfs 2011-03-04 10:41:56 -08:00
pci-stub.c PCI: pci-stub: ignore zero-length id parameters 2010-12-23 12:53:52 -08:00
pci-sysfs.c PCI: sysfs: Fix failure path for addition of "vpd" attribute 2011-02-08 10:02:46 -08:00
pci.c PCI/PM: Report wakeup events before resuming devices 2011-01-14 08:55:43 -08:00
pci.h PCI: Export ACPI _DSM provided firmware instance number and string name to sysfs 2011-03-04 10:41:56 -08:00
probe.c PCI: Avoid potential NULL pointer dereference in pci_scan_bridge 2011-02-08 13:08:05 -08:00
proc.c BKL: remove extraneous #include <smp_lock.h> 2010-11-17 08:59:32 -08:00
quirks.c PCI: do not create quirk I/O regions below PCIBIOS_MIN_IO for ICH 2011-03-04 10:42:32 -08:00
remove.c PCI: eliminate redundant pci_stop_dev() call from pci_destroy_dev() 2009-06-11 12:04:19 -07:00
rom.c PCI: fix rom.c kernel-doc warning 2009-02-13 12:01:56 -08:00
search.c PCI: use for_each_pci_dev() 2010-07-30 09:47:22 -07:00
setup-bus.c PCI: pre-allocate additional resources to devices only after successful allocation of essential resources. 2011-03-04 10:46:47 -08:00
setup-irq.c PCI: use for_each_pci_dev() 2010-07-30 09:47:22 -07:00
setup-res.c PCI: fix message typo 2010-10-17 20:03:05 -07:00
slot.c PCI: bus speed strings should be const 2010-08-31 15:28:00 -07:00
syscall.c headers: smp_lock.h redux 2009-07-12 12:22:34 -07:00
vpd.c pci: Add helper to search for VPD keywords 2010-02-28 00:43:33 -08:00
xen-pcifront.c xen-pcifront: fix PCI reference leak 2010-11-08 11:41:15 -05:00