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2014-11-06PCI: Allow numa_node override via sysfsPrarit Bhargava
NUMA systems with ACPI normally describe the physical topology via _PXM methods. But many BIOSes don't implement _PXM, which leaves the kernel with no way to discover the device topology, which reduces performance because we can't put memory and processes close to the device. The NUMA node of a PCI device is already exported in the sysfs "numa_node" file. Make that file writable so users can workaround the lack of _PXM methods in the BIOS. For example: echo 3 > /sys/devices/pci0000:ff/0000:03:1f.3/numa_node sets the node for PCI device 0000:03:1f.3. Writing the file emits a FW_BUG warning to encourage users to request firmware updates. It also taints the kernel with TAINT_FIRMWARE_WORKAROUND because overriding the node incorrectly can cause performance issues. [bhelgaas: changelog, documentation text] Signed-off-by: Prarit Bhargava <prarit@redhat.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> CC: Myron Stowe <mstowe@redhat.com> CC: Alexander Ducyk <alexander.h.duyck@redhat.com> CC: Jiang Liu <jiang.liu@linux.intel.com>
2014-10-01PCI/MSI: Add "msi_bus" sysfs MSI/MSI-X control for endpointsYijing Wang
The "msi_bus" sysfs file for bridges sets a bus flag to allow or disallow future driver requests for MSI or MSI-X. Previously, the sysfs file existed for endpoints but did nothing. Add "msi_bus" support for endpoints, so an administrator can prevent the use of MSI and MSI-X for individual devices. Note that as for bridges, these changes only affect future driver requests for MSI or MSI-X, so drivers may need to be reloaded. Add documentation for the "msi_bus" sysfs file. [bhelgaas: changelog, comments, add "subordinate", add endpoint printk, rework bus_flags setting, make bus_flags printk unconditional] Signed-off-by: Yijing Wang <wangyijing@huawei.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2014-05-28Merge branches 'pci/hotplug', 'pci/pci_is_bridge' and 'pci/virtualization' ↵Bjorn Helgaas
into next * pci/hotplug: PCI: cpqphp: Fix possible null pointer dereference NVMe: Implement PCIe reset notification callback PCI: Notify driver before and after device reset * pci/pci_is_bridge: pcmcia: Use pci_is_bridge() to simplify code PCI: pciehp: Use pci_is_bridge() to simplify code PCI: acpiphp: Use pci_is_bridge() to simplify code PCI: cpcihp: Use pci_is_bridge() to simplify code PCI: shpchp: Use pci_is_bridge() to simplify code PCI: rpaphp: Use pci_is_bridge() to simplify code sparc/PCI: Use pci_is_bridge() to simplify code powerpc/PCI: Use pci_is_bridge() to simplify code ia64/PCI: Use pci_is_bridge() to simplify code x86/PCI: Use pci_is_bridge() to simplify code PCI: Use pci_is_bridge() to simplify code PCI: Add new pci_is_bridge() interface PCI: Rename pci_is_bridge() to pci_has_subordinate() * pci/virtualization: PCI: Introduce new device binding path using pci_dev.driver_override Conflicts: drivers/pci/pci-sysfs.c
2014-05-28PCI: Introduce new device binding path using pci_dev.driver_overrideAlex Williamson
The driver_override field allows us to specify the driver for a device rather than relying on the driver to provide a positive match of the device. This shortcuts the existing process of looking up the vendor and device ID, adding them to the driver new_id, binding the device, then removing the ID, but it also provides a couple advantages. First, the above existing process allows the driver to bind to any device matching the new_id for the window where it's enabled. This is often not desired, such as the case of trying to bind a single device to a meta driver like pci-stub or vfio-pci. Using driver_override we can do this deterministically using: echo pci-stub > /sys/bus/pci/devices/0000:03:00.0/driver_override echo 0000:03:00.0 > /sys/bus/pci/devices/0000:03:00.0/driver/unbind echo 0000:03:00.0 > /sys/bus/pci/drivers_probe Previously we could not invoke drivers_probe after adding a device to new_id for a driver as we get non-deterministic behavior whether the driver we intend or the standard driver will claim the device. Now it becomes a deterministic process, only the driver matching driver_override will probe the device. To return the device to the standard driver, we simply clear the driver_override and reprobe the device: echo > /sys/bus/pci/devices/0000:03:00.0/driver_override echo 0000:03:00.0 > /sys/bus/pci/devices/0000:03:00.0/driver/unbind echo 0000:03:00.0 > /sys/bus/pci/drivers_probe Another advantage to this approach is that we can specify a driver override to force a specific binding or prevent any binding. For instance when an IOMMU group is exposed to userspace through VFIO we require that all devices within that group are owned by VFIO. However, devices can be hot-added into an IOMMU group, in which case we want to prevent the device from binding to any driver (override driver = "none") or perhaps have it automatically bind to vfio-pci. With driver_override it's a simple matter for this field to be set internally when the device is first discovered to prevent driver matches. Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Reviewed-by: Alexander Graf <agraf@suse.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-04-25PCI: Update my email addressBen Hutchings
Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2013-12-19PCI/MSI: Export MSI mode using attributes, not kobjectsGreg Kroah-Hartman
The PCI MSI sysfs code is a mess with kobjects for things that don't really need to be kobjects. This patch creates attributes dynamically for the MSI interrupts instead of using kobjects. Note, this removes a directory from sysfs. Old MSI kobjects: pci_device └── msi_irqs    └── 40    └── mode New MSI attributes: pci_device └── msi_irqs    └── 40 As there was only one file "mode" with the kobject model, the interrupt number is now a file that returns the "mode" of the interrupt (msi vs. msix). Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Acked-by: Neil Horman <nhorman@tuxdriver.com>
2013-06-03Finally eradicate CONFIG_HOTPLUGStephen Rothwell
Ever since commit 45f035ab9b8f ("CONFIG_HOTPLUG should be always on"), it has been basically impossible to build a kernel with CONFIG_HOTPLUG turned off. Remove all the remaining references to it. Cc: Russell King <linux@arm.linux.org.uk> Cc: Doug Thompson <dougthompson@xmission.com> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Pavel Machek <pavel@ucw.cz> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Acked-by: Mauro Carvalho Chehab <mchehab@redhat.com> Acked-by: Hans Verkuil <hans.verkuil@cisco.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-28PCI: SRIOV control and status via sysfs (documentation)Donald Dutile
Add documentation of new sysfs files and new pci_driver SRIOV configuration interface. [bhelgaas: changelog] Signed-off: Donald Dutile <ddutile@redhat.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2012-08-21PCI/PM: Add ABI document for sysfs file d3cold_allowedHuang Ying
This patch adds ABI document for the following sysfs file: /sys/bus/pci/devices/.../d3cold_allowed Signed-off-by: Huang Ying <ying.huang@intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Acked-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-12-05PCI/sysfs: add per pci device msi[x] irq listing (v5)Neil Horman
This patch adds a per-pci-device subdirectory in sysfs called: /sys/bus/pci/devices/<device>/msi_irqs This sub-directory exports the set of msi vectors allocated by a given pci device, by creating a numbered sub-directory for each vector beneath msi_irqs. For each vector various attributes can be exported. Currently the only attribute is called mode, which tracks the operational mode of that vector (msi vs. msix) Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2011-05-21PCI: add rescan to /sys/.../pci_bus/.../Yinghai Lu
After remove the device from /sys, we have to rescan all or find out the bridge and access /sys../device/rescan there. this patch add /sys/.../pci_bus/.../rescan. So user can rescan more easy. that is more clean and easy to understand. like after remove 0000:c4:00.0, you can rescan 0000:c4 directly. -v2: According to Jesse, use function instead of exposing attr, so could hide #ifdef in header file. also add code to remove rescan file in remove path. -v3: GregKH pointed out that we should use dev_attrs to avoid racing. So add pcibus_attrs and make it to be member of pcibus_attrs. -v4: Change name to pcibus_dev_attrs according to GregKH Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2011-03-04PCI: Export ACPI _DSM provided firmware instance number and string name to sysfsNarendra_K@Dell.com
This patch exports ACPI _DSM (Device Specific Method) provided firmware instance number and string name of PCI devices as defined by 'PCI Firmware Specification Revision 3.1' section 4.6.7.( DSM for Naming a PCI or PCI Express Device Under Operating Systems) to sysfs. New files created are: /sys/bus/pci/devices/.../label which contains the firmware name for the device in question, and /sys/bus/pci/devices/.../acpi_index which contains the firmware device type instance for the given device. cat /sys/devices/pci0000:00/0000:00:01.0/0000:01:00.0/acpi_index 1 cat /sys/devices/pci0000:00/0000:00:01.0/0000:01:00.0/label Embedded Broadcom 5709C NIC 1 cat /sys/devices/pci0000:00/0000:00:01.0/0000:01:00.1/acpi_index 2 cat /sys/devices/pci0000:00/0000:00:01.0/0000:01:00.1/label Embedded Broadcom 5709C NIC 2 The ACPI _DSM provided firmware 'instance number' and 'string name' will be given priority if the firmware also provides 'SMBIOS type 41 device type instance and string'. Signed-off-by: Matthew Garrett <mjg@redhat.com> Signed-off-by: Jordan Hargrave <jordan_hargrave@dell.com> Signed-off-by: Narendra K <narendra_k@dell.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2010-07-30PCI: export SMBIOS provided firmware instance and label to sysfsNarendra K
This patch exports SMBIOS provided firmware instance and label of onboard PCI devices to sysfs. New files are: /sys/bus/pci/devices/.../label which contains the firmware name for the device in question, and /sys/bus/pci/devices/.../index which contains the firmware device type instance for the given device. Signed-off-by: Jordan Hargrave <jordan_hargrave@dell.com> Signed-off-by: Narendra K <narendra_k@dell.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2010-06-11Revert "PCI: create function symlinks in /sys/bus/pci/slots/N/"Jesse Barnes
This reverts commit 75568f8094eb0333e9c2109b23cbc8b82d318a3c. Since they're just a convenience anyway, remove these symlinks since they're causing duplicate filename errors in the wild. Acked-by: Alex Chiang <achiang@canonical.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2010-05-11PCI: create function symlinks in /sys/bus/pci/slots/N/Alex Chiang
Create convenience symlinks in sysfs, linking slots to device functions, and vice versa. These links make it easier for users to figure out which devices actually live in what slots. For example: sapphire:/sys/bus/pci/slots # ls 1 10 2 3 4 5 6 7 8 9 sapphire:/sys/bus/pci/slots # ls -l 3 total 0 -r--r--r-- 1 root root 65536 Aug 18 14:10 address lrwxrwxrwx 1 root root 0 Aug 18 14:10 function0 -> ../../../../devices/pci0000:23/0000:23:01.0 lrwxrwxrwx 1 root root 0 Aug 18 14:10 function1 -> ../../../../devices/pci0000:23/0000:23:01.1 sapphire:/sys/bus/pci/slots # ls -l 3/function0/slot lrwxrwxrwx 1 root root 0 Aug 18 14:13 3/function0/slot -> ../../../bus/pci/slots/3 The original form of this patch was written by Matthew Wilcox, and was enhanced to include links from the sysfs slots/ directory pointing back at the device functions. Cc: willy@linux.intel.com Signed-off-by: Alex Chiang <achiang@hp.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-09-09PCI: expose function reset capability in sysfsMichael S. Tsirkin
Some devices allow an individual function to be reset without affecting other functions in the same device: that's what pci_reset_function does. For devices that have this support, expose reset attribite in sysfs. This is useful e.g. for virtualization, where a qemu userspace process wants to reset the device when the guest is reset, to emulate machine reboot as closely as possible. Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-06-16PCI hotplug: create symlink to hotplug driver moduleKenji Kaneshige
Create symbolic link to hotplug driver module in the PCI slot directory (/sys/bus/pci/slots/<SLOT#>). In the past, we need to load hotplug drivers one by one to identify the hotplug driver that handles the slot, and it was very inconvenient especially for trouble shooting. With this change, we can easily identify the hotplug driver. Signed-off-by: Taku Izumi <izumi.taku@jp.fujitsu.com> Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com> Reviewed-by: Alex Chiang <achiang@hp.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-03-20PCI: Introduce /sys/bus/pci/devices/.../rescanAlex Chiang
This interface allows the user to force a rescan of the device's parent bus and all subordinate buses, and rediscover devices removed earlier from this part of the device tree. Cc: Trent Piepho <xyzzy@speakeasy.org> Signed-off-by: Alex Chiang <achiang@hp.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-03-20PCI: Introduce /sys/bus/pci/devices/.../removeAlex Chiang
This patch adds an attribute named "remove" to a PCI device's sysfs directory. Writing a non-zero value to this attribute will remove the PCI device and any children of it. Trent Piepho wrote the original implementation and documentation. Thanks to Vegard Nossum for testing under kmemcheck and finding locking issues with the sysfs interface. Cc: Trent Piepho <xyzzy@speakeasy.org> Tested-by: Vegard Nossum <vegard.nossum@gmail.com> Signed-off-by: Alex Chiang <achiang@hp.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-03-20PCI: Introduce /sys/bus/pci/rescanAlex Chiang
This interface allows the user to force a rescan of all PCI buses in system, and rediscover devices that have been removed earlier. pci_bus_attrs implementation from Trent Piepho. Thanks to Vegard Nossum for discovering locking issues with the sysfs interface. Cc: Trent Piepho <xyzzy@speakeasy.org> Signed-off-by: Alex Chiang <achiang@hp.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-03-20PCI: document SR-IOV sysfs entriesYu Zhao
Reviewed-by: Randy Dunlap <rdunlap@xenotime.net> Reviewed-by: Matthew Wilcox <willy@linux.intel.com> Signed-off-by: Yu Zhao <yu.zhao@intel.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-03-20PCI: add remove_id sysfs entryChris Wright
This adds a remove_id sysfs entry to allow users of new_id to later remove the added dynid. One use case is management tools that want to dynamically bind/unbind devices to pci-stub driver while devices are assigned to KVM guests. Rather than having to track which driver was originally bound to the driver, a mangement tool can simply: Guest uses device Signed-off-by: Chris Wright <chrisw@sous-sol.org> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-02-24PCI: add some sysfs ABI docsChris Wright
Add sysfs ABI docs for driver entries bind, unbind and new_id. These entries are pretty old, from 2.6.0 onwards AFAIK, so this documents current behaviour. Signed-off-by: Chris Wright <chrisw@sous-sol.org> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Jesse Barnes <jbarnes@hobbes.lan>
2008-04-20PCI: Expose PCI VPD through sysfsBen Hutchings
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>