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2015-07-18include, lib: add __printf attributes to several function prototypesNicolas Iooss1-1/+1
Using __printf attributes helps to detect several format string issues at compile time (even though -Wformat-security is currently disabled in Makefile). For example it can detect when formatting a pointer as a number, like the issue fixed in commit a3fa71c40f18 ("wl18xx: show rx_frames_per_rates as an array as it really is"), or when the arguments do not match the format string, c.f. for example commit 5ce1aca81435 ("reiserfs: fix __RASSERT format string"). To prevent similar bugs in the future, add a __printf attribute to every function prototype which needs one in include/linux/ and lib/. These functions were mostly found by using gcc's -Wsuggest-attribute=format flag. Signed-off-by: Nicolas Iooss <nicolas.iooss_linux@m4x.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Felipe Balbi <balbi@ti.com> Cc: Joel Becker <jlbec@evilplan.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-06-11iommu: Introduce iommu_request_dm_for_dev()Joerg Roedel1-0/+6
This function can be called by an IOMMU driver to request that a device's default domain is direct mapped. Signed-off-by: Joerg Roedel <jroedel@suse.de>
2015-06-09iommu: Add function to query the default domain of a groupJoerg Roedel1-0/+1
This will be used to handle unity mappings in the iommu drivers. Signed-off-by: Joerg Roedel <jroedel@suse.de>
2015-06-09iommu: Introduce direct mapped region handlingJoerg Roedel1-0/+31
Add two new functions to the IOMMU-API to allow the IOMMU drivers to export the requirements for direct mapped regions per device. This is useful for exporting the information in Intel VT-d's RMRR entries or AMD-Vi's unity mappings. Signed-off-by: Joerg Roedel <jroedel@suse.de>
2015-06-09iommu: Add iommu_get_domain_for_dev functionJoerg Roedel1-0/+6
This function can be used to request the current domain a device is attached to. Signed-off-by: Joerg Roedel <jroedel@suse.de>
2015-03-31iommu: Remove domain_init and domain_free iommu_opsJoerg Roedel1-3/+0
All drivers have been converted to the new domain_alloc and domain_free iommu-ops. So remove the old ones and get rid of iommu_domain->priv too, as this is no longer needed when the struct iommu_domain is embedded in the private structures of the iommu drivers. Tested-by: Thierry Reding <treding@nvidia.com> Tested-by: Heiko Stuebner <heiko@sntech.de> Reviewed-by: Alex Williamson <alex.williamson@redhat.com> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
2015-03-31iommu: Introduce iommu domain typesJoerg Roedel1-1/+26
This allows to handle domains differently based on their type in the future. An IOMMU driver can implement certain optimizations for DMA-API domains for example. The domain types can be extended later and some of the existing domain attributes can be migrated to become domain flags. Tested-by: Thierry Reding <treding@nvidia.com> Tested-by: Heiko Stuebner <heiko@sntech.de> Reviewed-by: Alex Williamson <alex.williamson@redhat.com> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
2015-03-31iommu: Introduce domain_alloc and domain_free iommu_opsJoerg Roedel1-0/+5
These new call-backs defer the allocation and destruction of 'struct iommu_domain' to the iommu driver. This allows drivers to embed this struct into their private domain structures and to get rid of the domain_init and domain_destroy call-backs when all drivers have been converted. Tested-by: Thierry Reding <treding@nvidia.com> Tested-by: Heiko Stuebner <heiko@sntech.de> Reviewed-by: Alex Williamson <alex.williamson@redhat.com> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
2014-12-17Merge tag 'iommu-config-for-linus' of ↵Linus Torvalds1-0/+8
git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc Pull ARM SoC/iommu configuration update from Arnd Bergmann: "The iomm-config branch contains work from Will Deacon, quoting his description: This series adds automatic IOMMU and DMA-mapping configuration for OF-based DMA masters described using the generic IOMMU devicetree bindings. Although there is plenty of future work around splitting up iommu_ops, adding default IOMMU domains and sorting out automatic IOMMU group creation for the platform_bus, this is already useful enough for people to port over their IOMMU drivers and start using the new probing infrastructure (indeed, Marek has patches queued for the Exynos IOMMU). The branch touches core ARM and IOMMU driver files, and the respective maintainers (Russell King and Joerg Roedel) agreed to have the contents merged through the arm-soc tree. The final version was ready just before the merge window, so we ended up delaying it a bit longer than the rest, but we don't expect to see regressions because this is just additional infrastructure that will get used in drivers starting in 3.20 but is unused so far" * tag 'iommu-config-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: iommu: store DT-probed IOMMU data privately arm: dma-mapping: plumb our iommu mapping ops into arch_setup_dma_ops arm: call iommu_init before of_platform_populate dma-mapping: detect and configure IOMMU in of_dma_configure iommu: fix initialization without 'add_device' callback iommu: provide helper function to configure an IOMMU for an of master iommu: add new iommu_ops callback for adding an OF device dma-mapping: replace set_arch_dma_coherent_ops with arch_setup_dma_ops iommu: provide early initialisation hook for IOMMU drivers
2014-12-02Merge branches 'arm/omap', 'arm/msm', 'arm/rockchip', 'arm/renesas', ↵Joerg Roedel1-1/+24
'arm/smmu', 'x86/vt-d', 'x86/amd' and 'core' into next Conflicts: drivers/iommu/arm-smmu.c
2014-12-01iommu: add new iommu_ops callback for adding an OF deviceWill Deacon1-0/+6
This patch adds a new function to the iommu_ops structure to allow an OF device to be added to a specific IOMMU instance using the recently merged generic devicetree binding for IOMMUs. The callback (of_xlate) takes a struct device representing the master and an of_phandle_args representing the IOMMU and the correspondong IDs for the new master. Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Joerg Roedel <jroedel@suse.de> Acked-by: Marek Szyprowski <m.szyprowski@samsung.com> Tested-by: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-12-01iommu: provide early initialisation hook for IOMMU driversWill Deacon1-0/+2
IOMMU drivers must be initialised before any of their upstream devices, otherwise the relevant iommu_ops won't be configured for the bus in question. To solve this, a number of IOMMU drivers use initcalls to initialise the driver before anything has a chance to be probed. Whilst this solves the immediate problem, it leaves the job of probing the IOMMU completely separate from the iommu_ops to configure the IOMMU, which are called on a per-bus basis and require the driver to figure out exactly which instance of the IOMMU is being requested. In particular, the add_device callback simply passes a struct device to the driver, which then has to parse firmware tables or probe buses to identify the relevant IOMMU instance. This patch takes the first step in addressing this problem by adding an early initialisation pass for IOMMU drivers, giving them the ability to store some per-instance data in their iommu_ops structure and store that in their of_node. This can later be used when parsing OF masters to identify the IOMMU instance in question. Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Joerg Roedel <jroedel@suse.de> Acked-by: Marek Szyprowski <m.szyprowski@samsung.com> Tested-by: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-11-14iommu: add capability IOMMU_CAP_NOEXECAntonios Motakis1-0/+1
Some IOMMUs accept an IOMMU_NOEXEC protection flag in addition to IOMMU_READ and IOMMU_WRITE. Expose this as an IOMMU capability. Signed-off-by: Antonios Motakis <a.motakis@virtualopensystems.com> Acked-by: Joerg Roedel <jroedel@suse.de> Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-11-14iommu/arm-smmu: change IOMMU_EXEC to IOMMU_NOEXECAntonios Motakis1-1/+1
Exposing the XN flag of the SMMU driver as IOMMU_NOEXEC instead of IOMMU_EXEC makes it enforceable, since for IOMMUs that don't support the XN flag pages will always be executable. Signed-off-by: Antonios Motakis <a.motakis@virtualopensystems.com> Acked-by: Joerg Roedel <jroedel@suse.de> Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-11-04iommu: Add iommu_map_sg() functionOlav Haugan1-0/+22
Mapping and unmapping are more often than not in the critical path. map_sg allows IOMMU driver implementations to optimize the process of mapping buffers into the IOMMU page tables. Instead of mapping a buffer one page at a time and requiring potentially expensive TLB operations for each page, this function allows the driver to map all pages in one go and defer TLB maintenance until after all pages have been mapped. Additionally, the mapping operation would be faster in general since clients does not have to keep calling map API over and over again for each physically contiguous chunk of memory that needs to be mapped to a virtually contiguous region. Signed-off-by: Olav Haugan <ohaugan@codeaurora.org> Signed-off-by: Joerg Roedel <jroedel@suse.de>
2014-10-15Merge tag 'iommu-updates-v3.18' of ↵Linus Torvalds1-13/+12
git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu Pull IOMMU updates from Joerg Roedel: "This pull-request includes: - change in the IOMMU-API to convert the former iommu_domain_capable function to just iommu_capable - various fixes in handling RMRR ranges for the VT-d driver (one fix requires a device driver core change which was acked by Greg KH) - the AMD IOMMU driver now assigns and deassigns complete alias groups to fix issues with devices using the wrong PCI request-id - MMU-401 support for the ARM SMMU driver - multi-master IOMMU group support for the ARM SMMU driver - various other small fixes all over the place" * tag 'iommu-updates-v3.18' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (41 commits) iommu/vt-d: Work around broken RMRR firmware entries iommu/vt-d: Store bus information in RMRR PCI device path iommu/vt-d: Only remove domain when device is removed driver core: Add BUS_NOTIFY_REMOVED_DEVICE event iommu/amd: Fix devid mapping for ivrs_ioapic override iommu/irq_remapping: Fix the regression of hpet irq remapping iommu: Fix bus notifier breakage iommu/amd: Split init_iommu_group() from iommu_init_device() iommu: Rework iommu_group_get_for_pci_dev() iommu: Make of_device_id array const amd_iommu: do not dereference a NULL pointer address. iommu/omap: Remove omap_iommu unused owner field iommu: Remove iommu_domain_has_cap() API function IB/usnic: Convert to use new iommu_capable() API function vfio: Convert to use new iommu_capable() API function kvm: iommu: Convert to use new iommu_capable() API function iommu/tegra: Convert to iommu_capable() API function iommu/msm: Convert to iommu_capable() API function iommu/vt-d: Convert to iommu_capable() API function iommu/fsl: Convert to iommu_capable() API function ...
2014-09-29iommu: introduce domain attribute for nesting IOMMUsWill Deacon1-0/+1
Some IOMMUs, such as the ARM SMMU, support two stages of translation. The idea behind such a scheme is to allow a guest operating system to use the IOMMU for DMA mappings in the first stage of translation, with the hypervisor then installing mappings in the second stage to provide isolation of the DMA to the physical range assigned to that virtual machine. In order to allow IOMMU domains to be used for second-stage translation, this patch adds a new iommu_attr (IOMMU_ATTR_NESTING) for setting second-stage domains prior to device attach. The attribute can also be queried to see if a domain is actually making use of nesting. Acked-by: Joerg Roedel <jroedel@suse.de> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2014-09-25iommu: Remove iommu_domain_has_cap() API functionJoerg Roedel1-11/+0
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2014-09-25iommu: Introduce iommu_capable API functionJoerg Roedel1-0/+7
This function will replace the current iommu_domain_has_cap function and clean up the interface while at it. Signed-off-by: Joerg Roedel <jroedel@suse.de>
2014-09-25iommu: Convert iommu-caps from define to enumJoerg Roedel1-4/+7
Allow compile-time type-checking. Signed-off-by: Joerg Roedel <jroedel@suse.de>
2014-07-08iommu: Fix IOMMU sysfs stubsAlex Williamson1-6/+7
0-day kernel build testing reports: arch/x86/kvm/x86.o: In function `iommu_device_destroy': >> (.text+0x7a0a): multiple definition of `iommu_device_destroy' arch/x86/kvm/../../../virt/kvm/vfio.o:vfio.c:(.text+0x490): first defined here arch/x86/kvm/x86.o: In function `iommu_device_link': >> (.text+0x7a15): multiple definition of `iommu_device_link' arch/x86/kvm/../../../virt/kvm/vfio.o:vfio.c:(.text+0x49b): first defined here arch/x86/kvm/x86.o: In function `iommu_device_unlink': >> (.text+0x7a25): multiple definition of `iommu_device_unlink' arch/x86/kvm/../../../virt/kvm/vfio.o:vfio.c:(.text+0x4ab): first defined here arch/x86/kvm/x86.o: In function `iommu_device_create': >> (.text+0x79f8): multiple definition of `iommu_device_create' arch/x86/kvm/../../../virt/kvm/vfio.o:vfio.c:(.text+0x47e): first defined here These are due to failing to define the stubs as static inline. Fix. Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
2014-07-07iommu: Constify struct iommu_opsThierry Reding1-2/+2
This structure is read-only data and should never be modified. Signed-off-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Joerg Roedel <jroedel@suse.de>
2014-07-04iommu: Add sysfs support for IOMMUsAlex Williamson1-0/+26
IOMMUs currently have no common representation to userspace, most seem to have no representation at all aside from a few printks on bootup. There are however features of IOMMUs that are useful to know about. For instance the IOMMU might support superpages, making use of processor large/huge pages more important in a device assignment scenario. It's also useful to create cross links between devices and IOMMU hardware units, so that users might be able to load balance their devices to avoid thrashing a single hardware unit. This patch adds a device create and destroy interface as well as device linking, making it very lightweight for an IOMMU driver to add basic support. IOMMU drivers can provide additional attributes automatically by using an attribute_group. The attributes exposed are expected to be relatively device specific, the means to retrieve them certainly are, so there are currently no common attributes for the new class created here. Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
2014-07-04iommu/core: Create central IOMMU group lookup/creation interfaceAlex Williamson1-0/+1
Currently each IOMMU driver that supports IOMMU groups has its own code for discovering the base device used in grouping. This code is generally not specific to the IOMMU hardware, but to the bus of the devices managed by the IOMMU. We can therefore create a common interface for supporting devices on different buses. Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
2014-01-09Merge branches 'arm/smmu', 'core', 'x86/vt-d', 'arm/shmobile', 'x86/amd', ↵Joerg Roedel1-2/+7
'ppc/pamu', 'iommu/fixes' and 'arm/msm' into next
2014-01-07iommu: Rename domain_has_cap to iommu_domain_has_capUpinder Malhi (umalhi)1-2/+2
domain_has_cap is a misnomer bc the func name should be the same for CONFIG_IOMMU_API and !CONFIG_IOMMU_API. Signed-off-by: Upinder Malhi <umalhi@cisco.com> Signed-off-by: Joerg Roedel <joro@8bytes.org>
2013-12-30iommu: Add empty stub for iommu_group_get_by_id()Alexey Kardashevskiy1-0/+5
Almost every function in include/linux/iommu.h has an empty stub but the iommu_group_get_by_id() did not get one by mistake. This adds an empty stub for iommu_group_get_by_id() for IOMMU_API disabled config. Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Signed-off-by: Joerg Roedel <joro@8bytes.org>
2013-12-16iommu: add IOMMU_EXEC flag for safely allowing XN mappingsWill Deacon1-3/+4
Whilst most IOMMU mappings should probably be non-executable, there may be cases (HSA?) where executable mappings are required. This patch introduces a new mapping flag, IOMMU_EXEC, to indicate that the mapping should be mapped as executable. Signed-off-by: Will Deacon <will.deacon@arm.com>
2013-09-25iommu: Change iommu driver to call io_page_fault trace eventShuah Khan1-0/+2
Change iommu driver call io_page_fault trace event. This iommu_error class event can be enabled to trigger when an iommu error occurs. Trace information includes driver name, device name, iova, and flags. Testing: Added trace calls to iommu_prepare_identity_map() for testing some of the conditions that are hard to trigger. Here is the trace from the testing: swapper/0-1 [003] .... 2.003774: io_page_fault: IOMMU:pci 0000:00:02.0 iova=0x00000000cb800000 flags=0x0002 swapper/0-1 [003] .... 2.004098: io_page_fault: IOMMU:pci 0000:00:1d.0 iova=0x00000000cadc6000 flags=0x0002 swapper/0-1 [003] .... 2.004115: io_page_fault: IOMMU:pci 0000:00:1a.0 iova=0x00000000cadc6000 flags=0x0002 swapper/0-1 [003] .... 2.004129: io_page_fault: IOMMU:pci 0000:00:1f.0 iova=0x0000000000000000 flags=0x0002 Signed-off-by: Shuah Khan <shuah.kh@samsung.com> Signed-off-by: Joerg Roedel <joro@8bytes.org>
2013-08-14iommu/fsl: Add additional iommu attributes required by the PAMU driver.Varun Sethi1-0/+16
Added the following domain attributes for the FSL PAMU driver: 1. Added new iommu stash attribute, which allows setting of the LIODN specific stash id parameter through IOMMU API. 2. Added an attribute for enabling/disabling DMA to a particular memory window. 3. Added domain attribute to check for PAMUV1 specific constraints. Signed-off-by: Varun Sethi <Varun.Sethi@freescale.com> Signed-off-by: Joerg Roedel <joro@8bytes.org>
2013-05-02Merge branches 'iommu/fixes', 'x86/vt-d', 'x86/amd', 'ppc/pamu', 'core' and ↵Joerg Roedel1-9/+9
'arm/tegra' into next
2013-04-24iommu: Add a function to find an iommu group by idAlexey Kardashevskiy1-0/+1
As IOMMU groups are exposed to the user space by their numbers, the user space can use them in various kernel APIs so the kernel might need an API to find a group by its ID. As an example, QEMU VFIO on PPC64 platform needs it to associate a logical bus number (LIOBN) with a specific IOMMU group in order to support in-kernel handling of DMA map/unmap requests. The patch adds the iommu_group_get_by_id(id) function which performs such search. v2: fixed reference counting. Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Acked-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Joerg Roedel <joro@8bytes.org>
2013-04-19iommu: Include linux/err.hWang YanQing1-0/+1
The linux/iommu.h header uses ERR_PTR defined in linux/err.h but doesn't include it. Cc:joro@8bytes.org Reviewed-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Wang YanQing <udknight@gmail.com> Signed-off-by: Joerg Roedel <joro@8bytes.org>
2013-04-02iommu/fsl: Add the window permission flag as a parameter to ↵Varun Sethi1-3/+4
iommu_window_enable API. Each iommu window can have access permissions associated with it. Extended the window_enable API to incorporate window access permissions. In case of PAMU each window can have its specific set of permissions. Signed-off-by: Varun Sethi <Varun.Sethi@freescale.com> Signed-off-by: Joerg Roedel <joro@8bytes.org>
2013-04-02iommu/fsl: Make iova dma_addr_t in the iommu_iova_to_phys API.Varun Sethi1-6/+3
This is required in case of PAMU, as it can support a window size of up to 64G (even on 32bit). Signed-off-by: Varun Sethi <Varun.Sethi@freescale.com> Signed-off-by: Joerg Roedel <joro@8bytes.org>
2013-02-06iommu: Add DOMAIN_ATTR_WINDOWS domain attributeJoerg Roedel1-0/+5
This attribute can be used to set and get the number of subwindows on IOMMUs that are window-based. Signed-off-by: Joerg Roedel <joro@8bytes.org>
2013-02-06iommu: Add domain window handling functionsJoerg Roedel1-0/+22
Add the iommu_domain_window_enable() and iommu_domain_window_disable() functions to the IOMMU-API. These functions will be used to setup domains that are based on subwindows and not on paging. Signed-off-by: Joerg Roedel <joro@8bytes.org>
2013-02-06iommu: Implement DOMAIN_ATTR_PAGING attributeJoerg Roedel1-0/+1
This attribute of a domain can be queried to find out if the domain supports setting up page-tables using the iommu_map() and iommu_unmap() functions. Signed-off-by: Joerg Roedel <joro@8bytes.org>
2013-02-06iommu: Make sure DOMAIN_ATTR_MAX is really the maximumJoerg Roedel1-1/+1
Move it to the end of the list. Signed-off-by: Joerg Roedel <joro@8bytes.org>
2012-09-25iommu: static inline iommu group stub functionsAlex Williamson1-18/+24
Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2012-08-03iommu: Add missing forward declaration in include fileJoerg Roedel1-0/+1
The 'struct notifier_block' is not used in linux/iommu.h but not declared anywhere. Add a forward declaration for it. Reported-by: Thierry Reding <thierry.reding@avionic-design.de> Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2012-08-03iommu: Include linux/types.hThierry Reding1-0/+1
The linux/iommu.h header uses types defined in linux/types.h but doesn't include it. Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de> Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2012-07-23Merge branches 'iommu/fixes', 'x86/amd', 'groups', 'arm/tegra' and ↵Joerg Roedel1-3/+137
'api/domain-attr' into next Conflicts: drivers/iommu/iommu.c include/linux/iommu.h
2012-07-11iommu/amd: Implement DOMAIN_ATTR_GEOMETRY attributeJoerg Roedel1-0/+8
Implement the attribute itself and add the code for the AMD IOMMU driver. Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2012-07-11iommu: Add domain-attribute handlersJoerg Roedel1-1/+27
This patch introduces an extension to the iommu-api to get and set attributes for an iommu_domain. Two functions are introduced for this: * iommu_domain_get_attr() * iommu_domain_set_attr() These functions will be used to make the iommu-api suitable for GART-like IOMMUs and to implement hardware-specifc api-extensions. Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2012-06-25iommu: IOMMU GroupsAlex Williamson1-3/+101
IOMMU device groups are currently a rather vague associative notion with assembly required by the user or user level driver provider to do anything useful. This patch intends to grow the IOMMU group concept into something a bit more consumable. To do this, we first create an object representing the group, struct iommu_group. This structure is allocated (iommu_group_alloc) and filled (iommu_group_add_device) by the iommu driver. The iommu driver is free to add devices to the group using it's own set of policies. This allows inclusion of devices based on physical hardware or topology limitations of the platform, as well as soft requirements, such as multi-function trust levels or peer-to-peer protection of the interconnects. Each device may only belong to a single iommu group, which is linked from struct device.iommu_group. IOMMU groups are maintained using kobject reference counting, allowing for automatic removal of empty, unreferenced groups. It is the responsibility of the iommu driver to remove devices from the group (iommu_group_remove_device). IOMMU groups also include a userspace representation in sysfs under /sys/kernel/iommu_groups. When allocated, each group is given a dynamically assign ID (int). The ID is managed by the core IOMMU group code to support multiple heterogeneous iommu drivers, which could potentially collide in group naming/numbering. This also keeps group IDs to small, easily managed values. A directory is created under /sys/kernel/iommu_groups for each group. A further subdirectory named "devices" contains links to each device within the group. The iommu_group file in the device's sysfs directory, which formerly contained a group number when read, is now a link to the iommu group. Example: $ ls -l /sys/kernel/iommu_groups/26/devices/ total 0 lrwxrwxrwx. 1 root root 0 Apr 17 12:57 0000:00:1e.0 -> ../../../../devices/pci0000:00/0000:00:1e.0 lrwxrwxrwx. 1 root root 0 Apr 17 12:57 0000:06:0d.0 -> ../../../../devices/pci0000:00/0000:00:1e.0/0000:06:0d.0 lrwxrwxrwx. 1 root root 0 Apr 17 12:57 0000:06:0d.1 -> ../../../../devices/pci0000:00/0000:00:1e.0/0000:06:0d.1 $ ls -l /sys/kernel/iommu_groups/26/devices/*/iommu_group [truncating perms/owner/timestamp] /sys/kernel/iommu_groups/26/devices/0000:00:1e.0/iommu_group -> ../../../kernel/iommu_groups/26 /sys/kernel/iommu_groups/26/devices/0000:06:0d.0/iommu_group -> ../../../../kernel/iommu_groups/26 /sys/kernel/iommu_groups/26/devices/0000:06:0d.1/iommu_group -> ../../../../kernel/iommu_groups/26 Groups also include several exported functions for use by user level driver providers, for example VFIO. These include: iommu_group_get(): Acquires a reference to a group from a device iommu_group_put(): Releases reference iommu_group_for_each_dev(): Iterates over group devices using callback iommu_group_[un]register_notifier(): Allows notification of device add and remove operations relevant to the group iommu_group_id(): Return the group number This patch also extends the IOMMU API to allow attaching groups to domains. This is currently a simple wrapper for iterating through devices within a group, but it's expected that the IOMMU API may eventually make groups a more integral part of domains. Groups intentionally do not try to manage group ownership. A user level driver provider must independently acquire ownership for each device within a group before making use of the group as a whole. This may change in the future if group usage becomes more pervasive across both DMA and IOMMU ops. Groups intentionally do not provide a mechanism for driver locking or otherwise manipulating driver matching/probing of devices within the group. Such interfaces are generic to devices and beyond the scope of IOMMU groups. If implemented, user level providers have ready access via iommu_group_for_each_dev and group notifiers. iommu_device_group() is removed here as it has no users. The replacement is: group = iommu_group_get(dev); id = iommu_group_id(group); iommu_group_put(group); AMD-Vi & Intel VT-d support re-added in following patches. Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2012-05-22iommu/core: pass a user-provided token to fault handlersOhad Ben-Cohen1-4/+6
Sometimes a single IOMMU user may have to deal with several different IOMMU devices (e.g. remoteproc). When an IOMMU fault happens, such users have to regain their context in order to deal with the fault. Users can't use the private fields of neither the iommu_domain nor the IOMMU device, because those are already used by the IOMMU core and low level driver (respectively). This patch just simply allows users to pass a private token (most notably their own context pointer) to iommu_set_fault_handler(), and then makes sure it is provided back to the users whenever an IOMMU fault happens. The patch also adopts remoteproc to the new fault handling interface, but the real functionality using this (recovery of remote processors) will only be added later in a subsequent patch set. Cc: Fernando Guzman Lugo <fernando.lugo@ti.com> Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com> Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2012-01-09Merge branches 'iommu/page-sizes' and 'iommu/group-id' into nextJoerg Roedel1-0/+7
Conflicts: drivers/iommu/amd_iommu.c drivers/iommu/intel-iommu.c include/linux/iommu.h
2011-11-15iommu: Fix compile error with !IOMMU_APIJoerg Roedel1-1/+1
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2011-11-15iommu: Add iommu_device_group callback and iommu_group sysfs entryAlex Williamson1-0/+7
An IOMMU group is a set of devices for which the IOMMU cannot distinguish transactions. For PCI devices, a group often occurs when a PCI bridge is involved. Transactions from any device behind the bridge appear to be sourced from the bridge itself. We leave it to the IOMMU driver to define the grouping restraints for their platform. Using this new interface, the group for a device can be retrieved using the iommu_device_group() callback. Users will compare the value returned against the value returned for other devices to determine whether they are part of the same group. Devices with no group are not translated by the IOMMU. There should be no expectations about the group numbers as they may be arbitrarily assigned by the IOMMU driver and may not be persistent across boots. We also provide a sysfs interface to the group numbers here so that userspace can understand IOMMU dependencies between devices for managing safe, userspace drivers. [Some code changes by Joerg Roedel <joerg.roedel@amd.com>] Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>