linux/drivers/pci
Chris Wright 6faf17f6f1 PCI SR-IOV: correct broken resource alignment calculations
An SR-IOV capable device includes an SR-IOV PCIe capability which
describes the Virtual Function (VF) BAR requirements.  A typical SR-IOV
device can support multiple VFs whose BARs must be in a contiguous region,
effectively an array of VF BARs.  The BAR reports the size requirement
for a single VF.  We calculate the full range needed by simply multiplying
the VF BAR size with the number of possible VFs and create a resource
spanning the full range.

This all seems sane enough except it artificially inflates the alignment
requirement for the VF BAR.  The VF BAR need only be aligned to the size
of a single BAR not the contiguous range of VF BARs.  This can cause us
to fail to allocate resources for the BAR despite the fact that we
actually have enough space.

This patch adds a thin PCI specific layer over the generic
resource_alignment() function which is aware of the special nature of
VF BARs and does sorting and allocation based on the smaller alignment
requirement.

I recognize that while resource_alignment is generic, it's basically a
PCI helper.  An alternative to this patch is to add PCI VF BAR specific
information to struct resource.  I opted for the extra layer rather than
adding such PCI specific information to struct resource.  This does
have the slight downside that we don't cache the BAR size and re-read
for each alignment query (happens a small handful of times during boot
for each VF BAR).

Signed-off-by: Chris Wright <chrisw@sous-sol.org>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matthew Wilcox <matthew@wil.cx>
Cc: Yu Zhao <yu.zhao@intel.com>
Cc: stable@kernel.org
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-08-30 08:37:25 -07:00
..
hotplug PCI hotplug: SGI hotplug: do not use hotplug_slot_attr 2009-08-07 10:36:27 -07:00
pcie PCI ECRC: Remove unnecessary semicolons 2009-06-29 12:10:35 -07:00
.gitignore
access.c PCI: Add pci_bus_set_ops 2009-06-16 14:29:33 -07:00
bus.c PCI AER: support Multiple Error Received and no error source id 2009-06-16 14:30:13 -07:00
dmar.c VT-d: add device IOTLB invalidation support 2009-05-18 14:45:13 +01:00
hotplug-pci.c PCI: fix section mismatch warning in pci_scan_child_bus 2008-03-04 15:07:03 -08:00
hotplug.c Driver core: change add_uevent_var to use a struct 2007-10-12 14:51:01 -07:00
htirq.c Merge branch 'x86/apic' into irq/numa 2009-05-12 12:17:36 +02:00
intel-iommu.c intel-iommu: Fix enabling snooping feature by mistake 2009-08-06 11:35:50 +01:00
intr_remapping.c Intel-IOMMU, intr-remap: source-id checking 2009-06-23 22:09:17 +01:00
intr_remapping.h Intel-IOMMU, intr-remap: source-id checking 2009-06-23 22:09:17 +01:00
iov.c PCI SR-IOV: correct broken resource alignment calculations 2009-08-30 08:37:25 -07:00
iova.c Fix iommu address space allocation 2009-07-01 11:19:29 -07:00
irq.c PCI: struct device - replace bus_id with dev_name(), dev_set_name() 2009-01-07 11:12:23 -08:00
Kconfig PCI: initialize and release SR-IOV capability 2009-03-20 10:48:22 -07:00
Makefile Merge branch 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6 2009-06-22 11:59:51 -07:00
msi.c PCI MSI: Fix restoration of MSI/MSI-X mask states in suspend/resume 2009-06-29 12:18:13 -07:00
msi.h PCI MSI: shorten PCI_MSIX_ENTRY_* symbol names 2009-06-29 12:15:19 -07:00
pci-acpi.c Merge branch 'linus' into release 2009-04-05 02:14:15 -04:00
pci-driver.c PCI: check saved state before restore 2009-08-20 09:08:45 -07:00
pci-stub.c PCI: pci-stub module to reserve pci device 2009-01-07 11:12:38 -08:00
pci-sysfs.c docbooks: add/fix PCI kernel-doc 2009-04-22 14:49:33 -07:00
pci.c PCI: check saved state before restore 2009-08-20 09:08:45 -07:00
pci.h PCI SR-IOV: correct broken resource alignment calculations 2009-08-30 08:37:25 -07:00
probe.c PCI: use pci_is_root_bus() in pci_read_bridge_bases() 2009-06-16 14:29:31 -07:00
proc.c PCI: define PCI resource names in an 'enum' 2009-01-07 11:13:01 -08:00
quirks.c PCI: More PATA quirks for not entering D3 2009-06-29 12:14:04 -07:00
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 pci_is_root_bus() in pci_find_upstream_pcie_bridge() 2009-06-16 14:29:30 -07:00
setup-bus.c PCI SR-IOV: correct broken resource alignment calculations 2009-08-30 08:37:25 -07:00
setup-irq.c PCI: use dev_printk when possible 2008-06-25 16:05:13 -07:00
setup-res.c PCI SR-IOV: correct broken resource alignment calculations 2009-08-30 08:37:25 -07:00
slot.c PCI: fix kernel-doc warnings 2009-06-29 12:13:56 -07:00
syscall.c headers: smp_lock.h redux 2009-07-12 12:22:34 -07:00