litmus-rt.git/drivers/pci, branch linux-tip

Merge branch 'drivers' of git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile

2010-11-24T22:42:03+00:00

* 'drivers' of git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile:
  pci root complex: support for tile architecture
  drivers/net/tile/: on-chip network drivers for the tile architecture
  MAINTAINERS: add drivers/char/hvc_tile.c as maintained by tile

pci root complex: support for tile architecture

2010-11-24T18:13:49+00:00

This change enables PCI root complex support for TILEPro.  Unlike
TILE-Gx, TILEPro has no support for memory-mapped I/O, so the PCI
support consists of hypervisor upcalls for PIO, DMA, etc.  However,
the performance is fine for the devices we have tested with so far
(1Gb Ethernet, SATA, etc.).

The  header was tweaked to be a little bit more aggressive
about disabling attempts to map/unmap IO port space.  The hacky
 header was rolled into the  header
and the result was simplified.  Both of the latter two headers were
preliminary versions not meant for release before now - oh well.

There is one quirk for our TILEmpower platform, which accidentally
negotiates up to 5GT and needs to be kicked down to 2.5GT.

Signed-off-by: Chris Metcalf

BKL: remove extraneous #include

2010-11-17T16:59:32+00:00

The big kernel lock has been removed from all these files at some point,
leaving only the #include.

Remove this too as a cleanup.

Signed-off-by: Arnd Bergmann 
Signed-off-by: Linus Torvalds

PCI: fix offset check for sysfs mmapped files

2010-11-16T17:15:39+00:00

I just loaded 2.6.37-rc2 on my machines, and I noticed that X no longer starts.
Running an strace of the X server shows that it's doing this:

open("/sys/bus/pci/devices/0000:07:00.0/resource0", O_RDWR) = 10
mmap(NULL, 16777216, PROT_READ|PROT_WRITE, MAP_SHARED, 10, 0) = -1 EINVAL (Invalid argument)

This code seems to be asking for a shared read/write mapping of 16MB worth of
BAR0 starting at file offset 0, and letting the kernel assign a starting
address.  Unfortunately, this -EINVAL causes X not to start.  Looking into
dmesg, there's a complaint like so:

process "Xorg" tried to map 0x01000000 bytes at page 0x00000000 on 0000:07:00.0 BAR 0 (start 0x        96000000, size 0x         1000000)

...with the following code in pci_mmap_fits:

	pci_start = (mmap_api == PCI_MMAP_SYSFS) ?
		pci_resource_start(pdev, resno) >> PAGE_SHIFT : 0;
        if (start >= pci_start && start < pci_start + size &&
                        start + nr <= pci_start + size)

It looks like the logic here is set up such that when the mmap call comes via
sysfs, the check in pci_mmap_fits wants vma->vm_pgoff to be between the
resource's start and end address, and the end of the vma to be no farther than
the end.  However, the sysfs PCI resource files always start at offset zero,
which means that this test always fails for programs that mmap the sysfs files.
Given the comment in the original commit
3b519e4ea618b6943a82931630872907f9ac2c2b, I _think_ the old procfs files
require that the file offset be equal to the resource's base address when
mmapping.

I think what we want here is for pci_start to be 0 when mmap_api ==
PCI_MMAP_PROCFS.  The following patch makes that change, after which the Matrox
and Mach64 X drivers work again.

Acked-by: Martin Wilck 
Signed-off-by: Darrick J. Wong 
Signed-off-by: Jesse Barnes

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6

2010-11-15T22:01:33+00:00

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6:
  PCI: sysfs: fix printk warnings
  PCI: fix pci_bus_alloc_resource() hang, prefer positive decode
  PCI: read current power state at enable time
  PCI: fix size checks for mmap() on /proc/bus/pci files
  x86/PCI: coalesce overlapping host bridge windows
  PCI hotplug: ibmphp: Add check to prevent reading beyond mapped area

PCI: sysfs: fix printk warnings

2010-11-15T17:34:44+00:00

Cast pci_resource_start() and pci_resource_len() to u64 for printk.

drivers/pci/pci-sysfs.c:753: warning: format '%16Lx' expects type 'long long unsigned int', but argument 9 has type 'resource_size_t'
drivers/pci/pci-sysfs.c:753: warning: format '%16Lx' expects type 'long long unsigned int', but argument 10 has type 'resource_size_t'

Signed-off-by: Randy Dunlap 
Signed-off-by: Jesse Barnes

PCI: fix pci_bus_alloc_resource() hang, prefer positive decode

2010-11-12T17:16:08+00:00

When a PCI bus has two resources with the same start/end, e.g.,

    pci_bus 0000:04: resource 2 [mem 0xd0000000-0xd7ffffff pref]
    pci_bus 0000:04: resource 7 [mem 0xd0000000-0xd7ffffff]

the previous pci_bus_find_resource_prev() implementation would alternate
between them forever:

    pci_bus_find_resource_prev(... [mem 0xd0000000-0xd7ffffff pref])
        returns [mem 0xd0000000-0xd7ffffff]
    pci_bus_find_resource_prev(... [mem 0xd0000000-0xd7ffffff])
        returns [mem 0xd0000000-0xd7ffffff pref]
    pci_bus_find_resource_prev(... [mem 0xd0000000-0xd7ffffff pref])
        returns [mem 0xd0000000-0xd7ffffff]
    ...

This happened because there was no ordering between two resources with the
same start and end.  A resource that had the same start and end as the
cursor, but was not itself the cursor, was considered to be before the
cursor.

This patch fixes the hang by making a fixed ordering between any two
resources.

In addition, it tries to allocate from positively decoded regions before
using any subtractively decoded resources.  This means we will use a
positive decode region before a subtractive decode one, even if it means
using a smaller address.

Reference: https://bugzilla.kernel.org/show_bug.cgi?id=22062
Reported-by: Borislav Petkov 
Tested-by: Borislav Petkov 
Acked-by: Linus Torvalds 
Signed-off-by: Bjorn Helgaas 
Signed-off-by: Jesse Barnes

PCI: read current power state at enable time

2010-11-11T17:38:14+00:00

When we enable a PCI device, we avoid doing a lot of the initial setup
work if the device's enable count is non-zero.  If we don't fetch the
power state though, we may later fail to set up MSI due to the unknown
status.  So pick it up before we short circuit the rest due to a
pre-existing enable or mismatched enable/disable pair (as happens with
VGA devices, which are special in a special way).

Tested-by: Jesse Brandeburg 
Reported-by: Dave Airlie 
Tested-by: Dave Airlie 
Signed-off-by: Jesse Barnes

PCI: fix size checks for mmap() on /proc/bus/pci files

2010-11-11T17:34:32+00:00

The checks for valid mmaps of PCI resources made through /proc/bus/pci files
that were introduced in 9eff02e2042f96fb2aedd02e032eca1c5333d767 have several
problems:

1. mmap() calls on /proc/bus/pci files are made with real file offsets > 0,
whereas under /sys/bus/pci/devices, the start of the resource corresponds
to offset 0. This may lead to false negatives in pci_mmap_fits(), which
implicitly assumes the /sys/bus/pci/devices layout.

2. The loop in proc_bus_pci_mmap doesn't skip empty resouces. This leads
to false positives, because pci_mmap_fits() doesn't treat empty resources
correctly (the calculated size is 1 << (8*sizeof(resource_size_t)-PAGE_SHIFT)
in this case!).

3. If a user maps resources with BAR > 0, pci_mmap_fits will emit bogus
WARNINGS for the first resources that don't fit until the correct one is found.

On many controllers the first 2-4 BARs are used, and the others are empty.
In this case, an mmap attempt will first fail on the non-empty BARs
(including the "right" BAR because of 1.) and emit bogus WARNINGS because
of 3., and finally succeed on the first empty BAR because of 2.
This is certainly not the intended behaviour.

This patch addresses all 3 issues.
Updated with an enum type for the additional parameter for pci_mmap_fits().

Cc: stable@kernel.org
Signed-off-by: Martin Wilck 
Signed-off-by: Jesse Barnes

PCI hotplug: ibmphp: Add check to prevent reading beyond mapped area

2010-11-11T17:34:31+00:00

While testing various randconfigs with ktest.pl, I hit the following panic:

BUG: unable to handle kernel paging request at f7e54b03
IP: [] ibmphp_access_ebda+0x101/0x19bb

Adding printks, I found that the loop that reads the ebda blocks
can move out of the mapped section.

ibmphp_access_ebda: start=f7e44c00 size=5120 end=f7e46000
ibmphp_access_ebda: io_mem=f7e44d80 offset=384
ibmphp_access_ebda: io_mem=f7e54b03 offset=65283

The start of the iomap was at f7e44c00 and had a size of 5120,
making the end f7e46000. We start with an offset of 0x180 or
384, giving the first read at 0xf7e44d80. Reading that location
yields 65283, which is much bigger than the 5120 that was allocated
and makes the next read at f7e54b03 which is outside the mapped area.

Perhaps this is a bug in the driver, or buggy hardware, but this patch
is more about not crashing my box on start up and just giving a warning
if it detects this error.

This patch at least lets my box boot with just a warning.

Cc: Chandru Siddalingappa 
Signed-off-by: Steven Rostedt 
Signed-off-by: Jesse Barnes