These new PCI services allow to probe for 2.3-compliant INTx masking
support and then use the feature from PCI interrupt handlers. The
services are properly synchronized with concurrent config space access
via sysfs or on device reset.
This enables generic PCI device drivers like uio_pci_generic or KVM's
device assignment to implement the necessary kernel-side IRQ handling
without any knowledge about device-specific interrupt status and control
registers.
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
pci_block_user_cfg_access was designed for the use case that a single
context, the IPR driver, temporarily delays user space accesses to the
config space via sysfs. This assumption became invalid by the time
pci_dev_reset was added as locking instance. Today, if you run two loops
in parallel that reset the same device via sysfs, you end up with a
kernel BUG as pci_block_user_cfg_access detect the broken assumption.
This reworks the pci_block_user_cfg_access to a sleeping service
pci_cfg_access_lock and an atomic-compatible variant called
pci_cfg_access_trylock. The former not only blocks user space access as
before but also waits if access was already locked. The latter service
just returns false in this case, allowing the caller to resolve the
conflict instead of raising a BUG.
Adaptions of the ipr driver were originally written by Brian King.
Acked-by: Brian King <brking@linux.vnet.ibm.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Callers expect pci_user_{read,write}_config_*() to indicate errors by
returning negative values. Prior to this change, the indicated routines
could return positive error codes (e.g. PCIBIOS_BAD_REGISTER_NUMBER)
which callers would mistakenly interpret as success.
This change converts any non-zero return from the mentioned routines
into unambiguous negative value return codes.
Signed-off-by: Greg Thelen <gthelen@google.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
pci_vpd_pci22_write() calls pci_vpd_pci22_wait() after writing
PCI_VPD_DATA and PCI_VPD_ADDR to wait for the VPD operation to complete.
The result pci_vpd_pci22_wait() was not checked for error.
This change checks for error.
Signed-off-by: Greg Thelen <gthelen@google.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
pci_read/write_vpd() can fail due to a timeout. Usually the command
times out because of firmware issues (incorrect vpd length, etc.) on the
PCI card. Currently, the timeout occurs silently.
Output a message to the user indicating that they should check with
their vendor for new firmware.
Reviewed-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Prarit Bhargava <prarit@redhat.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
pci_lock must be a real spinlock in preempt-rt. Convert it to
raw_spinlock. No change for !RT kernels.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.
percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.
http://userweb.kernel.org/~tj/misc/slabh-sweep.py
The script does the followings.
* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.
* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.
* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.
The conversion was done in the following steps.
1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.
2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.
3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.
4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.
5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.
6. percpu.h was updated not to include slab.h.
7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).
* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig
8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.
Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
pci_bus_set_ops changes pci_ops associated with a pci_bus. This can be
used by debug tools such as PCIE AER error injection to fake some PCI
configuration registers.
Acked-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Add drivers/pci/*.c source files to DocBook/kernel-api.tmpl
and update those pci/*.c source files that need kernel-doc fixes.
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
The VPD on all devices may not be 32K. Unfortunately, there is no
generic way to find the size, so this adds a simple API hook
to reset it.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Change PCI VPD API which was only used by sysfs to something usable
in drivers.
* move iteration over multiple words to the low level
* use conventional types for arguments
* add exportable wrapper
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Accessing the VPD area can take a long time. The existing
VPD access code fails consistently on my hardware. There are comments
in the SysKonnect vendor driver that it can take up to 13ms per word.
Change the access routines to:
* use a mutex rather than spinning with IRQ's disabled and lock held
* have a much longer timeout
* call cond_resched while spinning
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Reviewed-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
For Broadcom 5706, 5708, 5709 rev. A nics, any read beyond the
VPD end tag will hang the device. This problem was initially
observed when a vpd entry was created in sysfs
('/sys/bus/pci/devices/<id>/vpd'). A read to this sysfs entry
will dump 32k of data. Reading a full 32k will cause an access
beyond the VPD end tag causing the device to hang. Once the device
is hung, the bnx2 driver will not be able to reset the device.
We believe that it is legal to read beyond the end tag and
therefore the solution is to limit the read/write length.
A majority of this patch is from Matthew Wilcox who gave code for
reworking the PCI vpd size information. A PCI quirk added for the
Broadcom NIC's to limit the read/write's.
Signed-off-by: Benjamin Li <benli@broadcom.com>
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Vital Product Data (VPD) may be exposed by PCI devices in several
ways. It is generally unsafe to read this information through the
existing interfaces to user-land because of stateful interfaces.
This adds:
- abstract operations for VPD access (struct pci_vpd_ops)
- VPD state information in struct pci_dev (struct pci_vpd)
- an implementation of the VPD access method specified in PCI 2.2
(in access.c)
- a 'vpd' binary file in sysfs directories for PCI devices with VPD
operations defined
It adds a probe for PCI 2.2 VPD in pci_scan_device() and release of
VPD state in pci_release_dev().
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The existing implementation of pci_block_user_cfg_access() was recently
criticised for providing out of date information and for returning errors
on write, which applications won't be expecting.
This reimplementation uses a global wait queue and a bit per device.
I've open-coded prepare_to_wait() / finish_wait() as I could optimise
it significantly by knowing that the pci_lock protected us at all points.
It looked a bit funny to be doing a spin_unlock_irqsave(); schedule(),
so I used spin_lock_irq() for the _user versions of pci_read_config and
pci_write_config. Not carrying a flags pointer around made the code
much less nasty.
Attempts to block an already blocked device hit a BUG() and attempts to
unblock an already unblocked device hit a WARN(). If we need to block
access to a device from userspace, it's because it's unsafe for even
another bit of the kernel to access the device. An attempt to block
a device for a second time means we're about to access the device to
perform some other operation, which could provoke undefined behaviour
from the device.
Signed-off-by: Matthew Wilcox <matthew@wil.cx>
Acked-by: Adam Belay <abelay@novell.com>
Acked-by: Alan Cox <alan@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch contains the following cleanups:
- access.c should #include "pci.h" for getting the prototypes of it's
global functions
- hotplug/shpchp_pci.c: make the needlessly global function
program_fw_provided_values() static
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Some PCI adapters (eg. ipr scsi adapters) have an exposure today in that they
issue BIST to the adapter to reset the card. If, during the time it takes to
complete BIST, userspace attempts to access PCI config space, the host bus
bridge will master abort the access since the ipr adapter does not respond on
the PCI bus for a brief period of time when running BIST. On PPC64 hardware,
this master abort results in the host PCI bridge isolating that PCI device
from the rest of the system, making the device unusable until Linux is
rebooted. This patch is an attempt to close that exposure by introducing some
blocking code in the PCI code. When blocked, writes will be humored and reads
will return the cached value. Ben Herrenschmidt has also mentioned that he
plans to use this in PPC power management.
Signed-off-by: Brian King <brking@us.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
drivers/pci/access.c | 89 ++++++++++++++++++++++++++++++++++++++++++++++++
drivers/pci/pci-sysfs.c | 20 +++++-----
drivers/pci/pci.h | 7 +++
drivers/pci/proc.c | 28 +++++++--------
drivers/pci/syscall.c | 14 +++----
include/linux/pci.h | 7 +++
6 files changed, 134 insertions(+), 31 deletions(-)
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
