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path: root/drivers/uio/uio_pci_generic.c
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2019-01-31uio/uio_pci_generic: Disable bus-mastering on releaseVenkatesh Srinivas
Userspace code using uio_pci_generic may enable bus-mastering by directly manipulating a PCI device's command register. If a userspace program enables bus-mastering but exits/crashes uncleanly, bus- mastering will still be enabled and stale DMA addresses may be programmed and live in the device. Disable bus-mastering unconditionally on last close of a UIO PCI fd to avoid this. If the device did not have bus-mastering enabled, pci_clear_master() is a no-op. Signed-off-by: Venkatesh Srinivas <venkateshs@google.com> Reviewed-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Catherine Sullivan <csully@google.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-21uio: add SPDX license tagsStephen Hemminger
For those without any license text present or short reference to GPL, add SPDX tag. Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18uio/uio_pci_generic: don't fail probe if pdev->irq == NULLJim Harris
Some userspace drivers and frameworks only poll and do not require interrupts to be available and enabled on the PCI device. So remove the requirement that an IRQ is assigned. If an IRQ is not assigned and a userspace driver tries to read()/write(), the generic uio framework will just return -EIO. This allows binding uio_pci_generic to devices which cannot get an IRQ assigned, such as an NVMe controller behind Intel Volume Management Device (VMD), since VMD does not support INTx interrupts. Signed-off-by: Jim Harris <james.r.harris@intel.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-01-12uio/uio_pci_generic: don't return zero on failure path in probe()Alexey Khoroshilov
If uio_register_device() fails in probe(), it breaks off initialization, deallocates all resources, but returns zero. The patch adds proper error code propagation. Found by Linux Driver Verification project (linuxtesting.org). Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru> Acked-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-05-21uio/uio_pci_generic: Use module_pci_driver to register driverPeter Huewe
Removing some boilerplate by using module_pci_driver instead of calling register and unregister in the otherwise empty init/exit functions. It removes a pr_info showing some details about the driver, but these infos can also be retrieved by using modinfo. The name of the pci_driver struct had to be changed in order to prevent a build failure. Signed-off-by: Peter Huewe <peterhuewe@gmx.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-21uio: remove use of __devinitBill Pemberton
CONFIG_HOTPLUG is going away as an option so __devinit is no longer needed. Signed-off-by: Bill Pemberton <wfp5p@virginia.edu> Cc: "Hans J. Koch" <hjk@hansjkoch.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-01-06uio: Convert uio_generic_pci to new intx masking APIJan Kiszka
The new PCI API provides both generic probing for 2.3 masking support and check&mask in the interrupt handler. 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>
2012-01-06PCI: Rework config space blocking servicesJan Kiszka
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>
2011-08-22uio: uio_pci_generic: Remove useless spin_lockHans J. Koch
The spin_lock in uio_pci_generic.c is only used in the interrupt handler, which cannot be executed twice at the same time. That makes the lock rather pointless. This patch removes it. Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Chris Wright <chrisw@redhat.com> Cc: Jesse Barnes <jbarnes@virtuousgeek.org> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Anthony Foiani <anthony.foiani@gmail.com> Reported-by: Anthony Foiani <anthony.foiani@gmail.com> Reported-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Hans J. Koch <hjk@hansjkoch.de> Acked-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-10-22uio: do not use PCI resources before pci_enable_device()Kulikov Vasiliy
IRQ and resource[] may not have correct values until after PCI hotplug setup occurs at pci_enable_device() time. The semantic match that finds this problem is as follows: // <smpl> @@ identifier x; identifier request ~= "pci_request.*|pci_resource.*"; @@ ( * x->irq | * x->resource | * request(x, ...) ) ... *pci_enable_device(x) // </smpl> Signed-off-by: Kulikov Vasiliy <segooon@gmail.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Hans J. Koch <hjk@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-03-30include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo
implicit slab.h inclusion from percpu.h 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>
2009-09-15uio: add generic driver for PCI 2.3 devicesMichael S. Tsirkin
This adds a generic uio driver that can bind to any PCI device. First user will be virtualization where a qemu userspace process needs to give guest OS access to the device. Interrupts are handled using the Interrupt Disable bit in the PCI command register and Interrupt Status bit in the PCI status register. All devices compliant to PCI 2.3 (circa 2002) and all compliant PCI Express devices should support these bits. Driver detects this support, and won't bind to devices which do not support the Interrupt Disable Bit in the command register. It's expected that more features of interest to virtualization will be added to this driver in the future. Possibilities are: mmap for device resources, MSI/MSI-X, eventfd (to interface with kvm), iommu. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Chris Wright <chrisw@redhat.com> Signed-off-by: Hans J. Koch <hjk@linutronix.de> Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>