summaryrefslogtreecommitdiff
path: root/arch/arm/xen
AgeCommit message (Collapse)Author
2015-12-21xen/arm: set the system time in Xen via the XENPF_settime64 hypercallStefano Stabellini
If Linux is running as dom0, call XENPF_settime64 to update the system time in Xen on pvclock_gtod notifications. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Acked-by: Arnd Bergmann <arnd@arndb.de>
2015-12-21xen/arm: introduce xen_read_wallclockStefano Stabellini
Read the wallclock from the shared info page at boot time. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Acked-by: Arnd Bergmann <arnd@arndb.de>
2015-12-21xen/arm: introduce HYPERVISOR_platform_op on arm and arm64Stefano Stabellini
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
2015-12-21xen/arm: account for stolen ticksStefano Stabellini
Register the runstate_memory_area with the hypervisor. Use pv_time_ops.steal_clock to account for stolen ticks. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
2015-11-07mm, page_alloc: distinguish between being unable to sleep, unwilling to ↵Mel Gorman
sleep and avoiding waking kswapd __GFP_WAIT has been used to identify atomic context in callers that hold spinlocks or are in interrupts. They are expected to be high priority and have access one of two watermarks lower than "min" which can be referred to as the "atomic reserve". __GFP_HIGH users get access to the first lower watermark and can be called the "high priority reserve". Over time, callers had a requirement to not block when fallback options were available. Some have abused __GFP_WAIT leading to a situation where an optimisitic allocation with a fallback option can access atomic reserves. This patch uses __GFP_ATOMIC to identify callers that are truely atomic, cannot sleep and have no alternative. High priority users continue to use __GFP_HIGH. __GFP_DIRECT_RECLAIM identifies callers that can sleep and are willing to enter direct reclaim. __GFP_KSWAPD_RECLAIM to identify callers that want to wake kswapd for background reclaim. __GFP_WAIT is redefined as a caller that is willing to enter direct reclaim and wake kswapd for background reclaim. This patch then converts a number of sites o __GFP_ATOMIC is used by callers that are high priority and have memory pools for those requests. GFP_ATOMIC uses this flag. o Callers that have a limited mempool to guarantee forward progress clear __GFP_DIRECT_RECLAIM but keep __GFP_KSWAPD_RECLAIM. bio allocations fall into this category where kswapd will still be woken but atomic reserves are not used as there is a one-entry mempool to guarantee progress. o Callers that are checking if they are non-blocking should use the helper gfpflags_allow_blocking() where possible. This is because checking for __GFP_WAIT as was done historically now can trigger false positives. Some exceptions like dm-crypt.c exist where the code intent is clearer if __GFP_DIRECT_RECLAIM is used instead of the helper due to flag manipulations. o Callers that built their own GFP flags instead of starting with GFP_KERNEL and friends now also need to specify __GFP_KSWAPD_RECLAIM. The first key hazard to watch out for is callers that removed __GFP_WAIT and was depending on access to atomic reserves for inconspicuous reasons. In some cases it may be appropriate for them to use __GFP_HIGH. The second key hazard is callers that assembled their own combination of GFP flags instead of starting with something like GFP_KERNEL. They may now wish to specify __GFP_KSWAPD_RECLAIM. It's almost certainly harmless if it's missed in most cases as other activity will wake kswapd. Signed-off-by: Mel Gorman <mgorman@techsingularity.net> Acked-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Christoph Lameter <cl@linux.com> Cc: David Rientjes <rientjes@google.com> Cc: Vitaly Wool <vitalywool@gmail.com> Cc: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-10-23xen/arm: don't try to re-register vcpu_info on cpu_hotplug.Stefano Stabellini
Call disable_percpu_irq on CPU_DYING and enable_percpu_irq when the cpu is coming up. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Reviewed-by: Julien Grall <julien.grall@citrix.com>
2015-10-23xen/arm: correct comment in enlighten.cJuergen Gross
Correct a comment in arch/arm/xen/enlighten.c referencing a wrong source file. Signed-off-by: Juergen Gross <jgross@suse.com> Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-10-23xen/swiotlb: Add support for 64KB page granularityJulien Grall
Swiotlb is used on ARM64 to support DMA on platform where devices are not protected by an SMMU. Furthermore it's only enabled for DOM0. While Xen is always using 4KB page granularity in the stage-2 page table, Linux ARM64 may either use 4KB or 64KB. This means that a Linux page can be spanned accross multiple Xen page. The Swiotlb code has to validate that the buffer used for DMA is physically contiguous in the memory. As a Linux page can't be shared between local memory and foreign page by design (the balloon code always removing entirely a Linux page), the changes in the code are very minimal because we only need to check the first Xen PFN. Note that it may be possible to optimize the function check_page_physically_contiguous to avoid looping over every Xen PFN for local memory. Although I will let this optimization for a follow-up. Signed-off-by: Julien Grall <julien.grall@citrix.com> Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-10-23xen/swiotlb: Pass addresses rather than frame numbers to xen_arch_need_swiotlbJulien Grall
With 64KB page granularity support, the frame number will be different. It will be easier to modify the behavior in a single place rather than in each caller. Signed-off-by: Julien Grall <julien.grall@citrix.com> Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-10-23arm/xen: Add support for 64KB page granularityJulien Grall
The hypercall interface is always using 4KB page granularity. This is requiring to use xen page definition macro when we deal with hypercall. Note that pfn_to_gfn is working with a Xen pfn (i.e 4KB). We may want to rename pfn_gfn to make this explicit. We also allocate a 64KB page for the shared page even though only the first 4KB is used. I don't think this is really important for now as it helps to have the pointer 4KB aligned (XENMEM_add_to_physmap is taking a Xen PFN). Signed-off-by: Julien Grall <julien.grall@citrix.com> Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-10-23xen/grant-table: Make it running on 64KB granularityJulien Grall
The Xen interface is using 4KB page granularity. This means that each grant is 4KB. The current implementation allocates a Linux page per grant. On Linux using 64KB page granularity, only the first 4KB of the page will be used. We could decrease the memory wasted by sharing the page with multiple grant. It will require some care with the {Set,Clear}ForeignPage macro. Note that no changes has been made in the x86 code because both Linux and Xen will only use 4KB page granularity. Signed-off-by: Julien Grall <julien.grall@citrix.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com> Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-09-14Merge branch 'fixes' of git://ftp.arm.linux.org.uk/~rmk/linux-armLinus Torvalds
Pull ARM fixes from Russell King: "A number of fixes for the merge window, fixing a number of cases missed when testing the uaccess code, particularly cases which only show up with certain compiler versions" * 'fixes' of git://ftp.arm.linux.org.uk/~rmk/linux-arm: ARM: 8431/1: fix alignement of __bug_table section entries arm/xen: Enable user access to the kernel before issuing a privcmd call ARM: domains: add memory dependencies to get_domain/set_domain ARM: domains: thread_info.h no longer needs asm/domains.h ARM: uaccess: fix undefined instruction on ARMv7M/noMMU ARM: uaccess: remove unneeded uaccess_save_and_disable macro ARM: swpan: fix nwfpe for uaccess changes ARM: 8429/1: disable GCC SRA optimization
2015-09-11arm/xen: Enable user access to the kernel before issuing a privcmd callJulien Grall
When Xen is copying data to/from the guest it will check if the kernel has the right to do the access. If not, the hypercall will return an error. After the commit a5e090acbf545c0a3b04080f8a488b17ec41fe02 "ARM: software-based privileged-no-access support", the kernel can't access any longer the user space by default. This will result to fail on every hypercall made by the userspace (i.e via privcmd). We have to enable the userspace access and then restore the correct permission every time the privcmd is used to made an hypercall. I didn't find generic helpers to do a these operations, so the change is only arm32 specific. Reported-by: Riku Voipio <riku.voipio@linaro.org> Signed-off-by: Julien Grall <julien.grall@citrix.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-09-08xen/privcmd: Further s/MFN/GFN/ clean-upJulien Grall
The privcmd code is mixing the usage of GFN and MFN within the same functions which make the code difficult to understand when you only work with auto-translated guests. The privcmd driver is only dealing with GFN so replace all the mention of MFN into GFN. The ioctl structure used to map foreign change has been left unchanged given that the userspace is using it. Nonetheless, add a comment to explain the expected value within the "mfn" field. Signed-off-by: Julien Grall <julien.grall@citrix.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-09-08xen: Make clear that swiotlb and biomerge are dealing with DMA addressJulien Grall
The swiotlb is required when programming a DMA address on ARM when a device is not protected by an IOMMU. In this case, the DMA address should always be equal to the machine address. For DOM0 memory, Xen ensure it by have an identity mapping between the guest address and host address. However, when mapping a foreign grant reference, the 1:1 model doesn't work. For ARM guest, most of the callers of pfn_to_mfn expects to get a GFN (Guest Frame Number), i.e a PFN (Page Frame Number) from the Linux point of view given that all ARM guest are auto-translated. Even though the name pfn_to_mfn is misleading, we need to ensure that those caller get a GFN and not by mistake a MFN. In pratical, I haven't seen error related to this but we should fix it for the sake of correctness. In order to fix the implementation of pfn_to_mfn on ARM in a follow-up patch, we have to introduce new helpers to return the DMA from a PFN and the invert. On x86, the new helpers will be an alias of pfn_to_mfn and mfn_to_pfn. The helpers will be used in swiotlb and xen_biovec_phys_mergeable. This is necessary in the latter because we have to ensure that the biovec code will not try to merge a biovec using foreign page and another using Linux memory. Lastly, the helper mfn_to_local_pfn has been renamed to bfn_to_local_pfn given that the only usage was in swiotlb. Signed-off-by: Julien Grall <julien.grall@citrix.com> Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-08-20arm/xen: Drop the definition of xen_pci_platform_unplugJulien Grall
The commit 6f6c15ef912465b3aaafe709f39bd6026a8b3e72 "xen/pvhvm: Remove the xen_platform_pci int." makes the x86 version of xen_pci_platform_unplug static. Therefore we don't need anymore to define a dummy xen_pci_platform_unplug for ARM. Signed-off-by: Julien Grall <julien.grall@citrix.com> Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
2015-08-20xen/events: Support event channel rebind on ARMJulien Grall
Currently, the event channel rebind code is gated with the presence of the vector callback. The virtual interrupt controller on ARM has the concept of per-CPU interrupt (PPI) which allow us to support per-VCPU event channel. Therefore there is no need of vector callback for ARM. Xen is already using a free PPI to notify the guest VCPU of an event. Furthermore, the xen code initialization in Linux (see arch/arm/xen/enlighten.c) is requesting correctly a per-CPU IRQ. Introduce new helper xen_support_evtchn_rebind to allow architecture decide whether rebind an event is support or not. It will always return true on ARM and keep the same behavior on x86. This is also allow us to drop the usage of xen_have_vector_callback entirely in the ARM code. Signed-off-by: Julien Grall <julien.grall@citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-06-17xen: Include xen/page.h rather than asm/xen/page.hJulien Grall
Using xen/page.h will be necessary later for using common xen page helpers. As xen/page.h already include asm/xen/page.h, always use the later. Signed-off-by: Julien Grall <julien.grall@citrix.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com> Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Cc: Ian Campbell <ian.campbell@citrix.com> Cc: Wei Liu <wei.liu2@citrix.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: netdev@vger.kernel.org Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-05-28xen/arm: allow console=hvc0 to be omitted for guestsArd Biesheuvel
From: Ard Biesheuvel <ard.biesheuvel@linaro.org> This patch registers hvc0 as the preferred console if no console has been specified explicitly on the kernel command line. The purpose is to allow platform agnostic kernels and boot images (such as distro installers) to boot in a Xen/ARM domU without the need to modify the command line by hand. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Reviewed-by: Julien Grall <julien.grall@linaro.org>
2015-05-28arm,arm64/xen: move Xen initialization earlierStefano Stabellini
Currently, Xen is initialized/discovered in an initcall. This doesn't allow us to support earlyprintk or choosing the preferred console when running on Xen. The current function xen_guest_init is now split in 2 parts: - xen_early_init: Check if there is a Xen node in the device tree and setup domain type - xen_guest_init: Retrieve the information from the device node and initialize Xen (grant table, shared page...) The former is called in setup_arch, while the latter is an initcall. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Julien Grall <julien.grall@linaro.org> Acked-by: Ian Campbell <ian.campbell@citrix.com> Acked-by: Will Deacon <will.deacon@arm.com>
2015-05-28arm/xen: Correctly check if the event channel interrupt is presentJulien Grall
The function irq_of_parse_and_map returns 0 when the IRQ is not found. Futhermore, move the check before notifying the user that we are running on Xen. Signed-off-by: Julien Grall <julien.grall@linaro.org> Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Acked-by: Ian Campbell <ian.campbell@citrix.com>
2015-05-18xen/arm: Define xen_arch_suspend()Boris Ostrovsky
Commit 2b953a5e994c ("xen: Suspend ticks on all CPUs during suspend") introduced xen_arch_suspend() routine but did so only for x86, breaking ARM builds. We need to add it to ARM as well. Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Reported-by: Michal Suchanek <hramrach@gmail.com> Tested-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-05-06xen: Add __GFP_DMA flag when xen_swiotlb_init gets free pages on ARMStefano Stabellini
Make sure that xen_swiotlb_init allocates buffers that are DMA capable when at least one memblock is available below 4G. Otherwise we assume that all devices on the SoC can cope with >4G addresses. We do this on ARM and ARM64, where dom0 is mapped 1:1, so pfn == mfn in this case. No functional changes on x86. From: Chen Baozi <baozich@gmail.com> Signed-off-by: Chen Baozi <baozich@gmail.com> Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Tested-by: Chen Baozi <baozich@gmail.com> Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-03-16xen/privcmd: improve performance of MMAPBATCH_V2David Vrabel
Make the IOCTL_PRIVCMD_MMAPBATCH_V2 (and older V1 version) map multiple frames at a time rather than one at a time, despite the pages being non-consecutive GFNs. xen_remap_foreign_mfn_array() is added which maps an array of GFNs (instead of a consecutive range of GFNs). Since per-frame errors are returned in an array, privcmd must set the MMAPBATCH_V1 error bits as part of the "report errors" phase, after all the frames are mapped. Migrate times are significantly improved (when using a PV toolstack domain). For example, for an idle 12 GiB PV guest: Before After real 0m38.179s 0m26.868s user 0m15.096s 0m13.652s sys 0m28.988s 0m18.732s Signed-off-by: David Vrabel <david.vrabel@citrix.com> Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
2015-03-16xen: unify foreign GFN map/unmap for auto-xlated physmap guestsDavid Vrabel
Auto-translated physmap guests (arm, arm64 and x86 PVHVM/PVH) map and unmap foreign GFNs using the same method (updating the physmap). Unify the two arm and x86 implementations into one commont one. Note that on arm and arm64, the correct error code will be returned (instead of always -EFAULT) and map/unmap failure warnings are no longer printed. These changes are required if the foreign domain is paging (-ENOENT failures are expected and must be propagated up to the caller). Signed-off-by: David Vrabel <david.vrabel@citrix.com> Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
2015-01-28xen/grant-table: pre-populate kernel unmap ops for xen_gnttab_unmap_refs()David Vrabel
When unmapping grants, instead of converting the kernel map ops to unmap ops on the fly, pre-populate the set of unmap ops. This allows the grant unmap for the kernel mappings to be trivially batched in the future. Signed-off-by: David Vrabel <david.vrabel@citrix.com> Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
2015-01-20arm64: Relax licensing of arm64 Xen DMA operationsChuck Tuffli
With Xen configured into the arm64 kernel, any driver allocating DMA'able memory for PCI operations, must be GPL compatible, regardless of its interaction with Xen. This patch relaxes the GPL requirement of xen_dma_ops and its dependencies to allow open source drivers to be compiled for the arm64 architecture. Signed-off-by: Chuck Tuffli <chuck.tuffli@emulex.com>
2014-12-04xen/arm: introduce GNTTABOP_cache_flushStefano Stabellini
Introduce support for new hypercall GNTTABOP_cache_flush. Use it to perform cache flashing on pages used for dma when necessary. If GNTTABOP_cache_flush is supported by the hypervisor, we don't need to bounce dma map operations that involve foreign grants and non-coherent devices. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Ian Campbell <ian.campbell@citrix.com>
2014-12-04xen/arm/arm64: introduce xen_arch_need_swiotlbStefano Stabellini
Introduce an arch specific function to find out whether a particular dma mapping operation needs to bounce on the swiotlb buffer. On ARM and ARM64, if the page involved is a foreign page and the device is not coherent, we need to bounce because at unmap time we cannot execute any required cache maintenance operations (we don't know how to find the pfn from the mfn). No change of behaviour for x86. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Ian Campbell <ian.campbell@citrix.com> Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2014-12-04xen/arm/arm64: merge xen/mm32.c into xen/mm.cStefano Stabellini
Merge xen/mm32.c into xen/mm.c. As a consequence the code gets compiled on arm64 too. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
2014-12-04xen/arm: use hypercall to flush caches in map_pageStefano Stabellini
In xen_dma_map_page, if the page is a local page, call the native map_page dma_ops. If the page is foreign, call __xen_dma_map_page that issues any required cache maintenane operations via hypercall. The reason for doing this is that the native dma_ops map_page could allocate buffers than need to be freed. If the page is foreign we don't call the native unmap_page dma_ops function, resulting in a memory leak. Suggested-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
2014-12-04xen/arm: use is_device_dma_coherentStefano Stabellini
Use is_device_dma_coherent to check whether we need to issue cache maintenance operations rather than checking on the existence of a particular dma_ops function for the device. This is correct because coherent devices don't need cache maintenance operations - arm_coherent_dma_ops does not set the hooks that we were previously checking for existance. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Ian Campbell <ian.campbell@citrix.com>
2014-12-04xen/arm: if(pfn_valid(pfn)) call native dma_opsStefano Stabellini
Remove code duplication in mm32.c by calling the native dma_ops if the page is a local page (not a foreign page). Use a simple pfn_valid(pfn) check to figure out if the page is local, exploiting the fact that dom0 is mapped 1:1, therefore pfn_valid always returns false when called on a foreign mfn. Suggested-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
2014-12-04xen/arm: remove outer_*_range callStefano Stabellini
Dom0 is not actually capable of issuing outer_inv_range or outer_clean_range calls. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Acked-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
2014-12-04xen/arm: remove handling of XENFEAT_grant_map_identityStefano Stabellini
The feature has been removed from Xen. Also Linux cannot use it on ARM32 without CONFIG_ARM_LPAE. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Acked-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
2014-09-11xen/arm: remove mach_to_phys rbtreeStefano Stabellini
Remove the rbtree used to keep track of machine to physical mappings: the frontend can grant the same page multiple times, leading to errors inserting or removing entries from the mach_to_phys tree. Linux only needed to know the physical address corresponding to a given machine address in swiotlb-xen. Now that swiotlb-xen can call the xen_dma_* functions passing the machine address directly, we can remove it. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Tested-by: Denis Schneider <v1ne2go@gmail.com>
2014-09-11xen/arm: reimplement xen_dma_unmap_page & friendsStefano Stabellini
xen_dma_unmap_page, xen_dma_sync_single_for_cpu and xen_dma_sync_single_for_device are currently implemented by calling into the corresponding generic ARM implementation of these functions. In order to do this, firstly the dma_addr_t handle, that on Xen is a machine address, needs to be translated into a physical address. The operation is expensive and inaccurate, given that a single machine address can correspond to multiple physical addresses in one domain, because the same page can be granted multiple times by the frontend. To avoid this problem, we introduce a Xen specific implementation of xen_dma_unmap_page, xen_dma_sync_single_for_cpu and xen_dma_sync_single_for_device, that can operate on machine addresses directly. The new implementation relies on the fact that the hypervisor creates a second p2m mapping of any grant pages at physical address == machine address of the page for dom0. Therefore we can access memory at physical address == dma_addr_r handle and perform the cache flushing there. Some cache maintenance operations require a virtual address. Instead of using ioremap_cache, that is not safe in interrupt context, we allocate a per-cpu PAGE_KERNEL scratch page and we manually update the pte for it. arm64 doesn't need cache maintenance operations on unmap for now. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Tested-by: Denis Schneider <v1ne2go@gmail.com>
2014-09-11xen/arm: introduce XENFEAT_grant_map_identityStefano Stabellini
The flag tells us that the hypervisor maps a grant page to guest physical address == machine address of the page in addition to the normal grant mapping address. It is needed to properly issue cache maintenance operation at the completion of a DMA operation involving a foreign grant. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Tested-by: Denis Schneider <v1ne2go@gmail.com>
2014-08-11arm/xen: remove duplicate arch_gnttab_init() functionDavid Vrabel
This was introduced in commit e306e3be1cbe (Merge tag 'stable/for-linus-3.17-rc0-tag'). Signed-off-by: David Vrabel <david.vrabel@citrix.com> Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
2014-08-07Merge tag 'stable/for-linus-3.17-rc0-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull Xen updates from David Vrabel: - remove unused V2 grant table support - note that Konrad is xen-blkkback/front maintainer - add 'xen_nopv' option to disable PV extentions for x86 HVM guests - misc minor cleanups * tag 'stable/for-linus-3.17-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: xen-pciback: Document the 'quirks' sysfs file xen/pciback: Fix error return code in xen_pcibk_attach() xen/events: drop negativity check of unsigned parameter xen/setup: Remove Identity Map Debug Message xen/events/fifo: remove a unecessary use of BM() xen/events/fifo: ensure all bitops are properly aligned even on x86 xen/events/fifo: reset control block and local HEADs on resume xen/arm: use BUG_ON xen/grant-table: remove support for V2 tables x86/xen: safely map and unmap grant frames when in atomic context MAINTAINERS: Make me the Xen block subsystem (front and back) maintainer xen: Introduce 'xen_nopv' to disable PV extensions for HVM guests.
2014-08-05Merge branch 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-armLinus Torvalds
Pull ARM updates from Russell King: "Included in this update: - perf updates from Will Deacon: The main changes are callchain stability fixes from Jean Pihet and event mapping and PMU name rework from Mark Rutland The latter is preparatory work for enabling some code re-use with arm64 in the future. - updates for nommu from Uwe Kleine-König: Two different fixes for the same problem making some ARM nommu configurations not boot since 3.6-rc1. The problem is that user_addr_max returned the biggest available RAM address which makes some copy_from_user variants fail to read from XIP memory. - deprecate legacy OMAP DMA API, in preparation for it's removal. The popular drivers have been converted over, leaving a very small number of rarely used drivers, which hopefully can be converted during the next cycle with a bit more visibility (and hopefully people popping out of the woodwork to help test) - more tweaks for BE systems, particularly with the kernel image format. In connection with this, I've cleaned up the way we generate the linker script for the decompressor. - removal of hard-coded assumptions of the kernel stack size, making everywhere depend on the value of THREAD_SIZE_ORDER. - MCPM updates from Nicolas Pitre. - Make it easier for proper CPU part number checks (which should always include the vendor field). - Assembly code optimisation - use the "bx" instruction when returning from a function on ARMv6+ rather than "mov pc, reg". - Save the last kernel misaligned fault location and report it via the procfs alignment file. - Clean up the way we create the initial stack frame, which is a repeated pattern in several different locations. - Support for 8-byte get_user(), needed for some DRM implementations. - mcs locking from Will Deacon. - Save and restore a few more Cortex-A9 registers (for errata workarounds) - Fix various aspects of the SWP emulation, and the ELF hwcap for the SWP instruction. - Update LPAE logic for pte_write and pmd_write to make it more correct. - Support for Broadcom Brahma15 CPU cores. - ARM assembly crypto updates from Ard Biesheuvel" * 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm: (53 commits) ARM: add comments to the early page table remap code ARM: 8122/1: smp_scu: enable SCU standby support ARM: 8121/1: smp_scu: use macro for SCU enable bit ARM: 8120/1: crypto: sha512: add ARM NEON implementation ARM: 8119/1: crypto: sha1: add ARM NEON implementation ARM: 8118/1: crypto: sha1/make use of common SHA-1 structures ARM: 8113/1: remove remaining definitions of PLAT_PHYS_OFFSET from <mach/memory.h> ARM: 8111/1: Enable erratum 798181 for Broadcom Brahma-B15 ARM: 8110/1: do CPU-specific init for Broadcom Brahma15 cores ARM: 8109/1: mm: Modify pte_write and pmd_write logic for LPAE ARM: 8108/1: mm: Introduce {pte,pmd}_isset and {pte,pmd}_isclear ARM: hwcap: disable HWCAP_SWP if the CPU advertises it has exclusives ARM: SWP emulation: only initialise on ARMv7 CPUs ARM: SWP emulation: always enable when SMP is enabled ARM: 8103/1: save/restore Cortex-A9 CP15 registers on suspend/resume ARM: 8098/1: mcs lock: implement wfe-based polling for MCS locking ARM: 8091/2: add get_user() support for 8 byte types ARM: 8097/1: unistd.h: relocate comments back to place ARM: 8096/1: Describe required sort order for textofs-y (TEXT_OFFSET) ARM: 8090/1: add revision info for PL310 errata 588369 and 727915 ...
2014-07-30x86/xen: safely map and unmap grant frames when in atomic contextDavid Vrabel
arch_gnttab_map_frames() and arch_gnttab_unmap_frames() are called in atomic context but were calling alloc_vm_area() which might sleep. Also, if a driver attempts to allocate a grant ref from an interrupt and the table needs expanding, then the CPU may already by in lazy MMU mode and apply_to_page_range() will BUG when it tries to re-enable lazy MMU mode. These two functions are only used in PV guests. Introduce arch_gnttab_init() to allocates the virtual address space in advance. Avoid the use of apply_to_page_range() by using saving and using the array of PTE addresses from the alloc_vm_area() call (which ensures that the required page tables are pre-allocated). Signed-off-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2014-07-25xen/arm: use BUG_ONHimangi Saraogi
Use BUG_ON(x) rather than if(x) BUG(); The semantic patch that fixes this problem is as follows: // <smpl> @@ identifier x; @@ -if (x) BUG(); +BUG_ON(x); // </smpl> Signed-off-by: Himangi Saraogi <himangi774@gmail.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
2014-07-18ARM: convert all "mov.* pc, reg" to "bx reg" for ARMv6+Russell King
ARMv6 and greater introduced a new instruction ("bx") which can be used to return from function calls. Recent CPUs perform better when the "bx lr" instruction is used rather than the "mov pc, lr" instruction, and this sequence is strongly recommended to be used by the ARM architecture manual (section A.4.1.1). We provide a new macro "ret" with all its variants for the condition code which will resolve to the appropriate instruction. Rather than doing this piecemeal, and miss some instances, change all the "mov pc" instances to use the new macro, with the exception of the "movs" instruction and the kprobes code. This allows us to detect the "mov pc, lr" case and fix it up - and also gives us the possibility of deploying this for other registers depending on the CPU selection. Reported-by: Will Deacon <will.deacon@arm.com> Tested-by: Stephen Warren <swarren@nvidia.com> # Tegra Jetson TK1 Tested-by: Robert Jarzmik <robert.jarzmik@free.fr> # mioa701_bootresume.S Tested-by: Andrew Lunn <andrew@lunn.ch> # Kirkwood Tested-by: Shawn Guo <shawn.guo@freescale.com> Tested-by: Tony Lindgren <tony@atomide.com> # OMAPs Tested-by: Gregory CLEMENT <gregory.clement@free-electrons.com> # Armada XP, 375, 385 Acked-by: Sekhar Nori <nsekhar@ti.com> # DaVinci Acked-by: Christoffer Dall <christoffer.dall@linaro.org> # kvm/hyp Acked-by: Haojian Zhuang <haojian.zhuang@gmail.com> # PXA3xx Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> # Xen Tested-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> # ARMv7M Tested-by: Simon Horman <horms+renesas@verge.net.au> # Shmobile Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-07-14xen/grant-table: remove support for V2 tablesDavid Vrabel
Since 11c7ff17c9b6dbf3a4e4f36be30ad531a6cf0ec9 (xen/grant-table: Force to use v1 of grants.) the code for V2 grant tables is not used. Signed-off-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2014-07-14x86/xen: safely map and unmap grant frames when in atomic contextDavid Vrabel
arch_gnttab_map_frames() and arch_gnttab_unmap_frames() are called in atomic context but were calling alloc_vm_area() which might sleep. Also, if a driver attempts to allocate a grant ref from an interrupt and the table needs expanding, then the CPU may already by in lazy MMU mode and apply_to_page_range() will BUG when it tries to re-enable lazy MMU mode. These two functions are only used in PV guests. Introduce arch_gnttab_init() to allocates the virtual address space in advance. Avoid the use of apply_to_page_range() by using saving and using the array of PTE addresses from the alloc_vm_area() call. N.B. 'alloc_vm_area' pre-allocates the pagetable so there is no need to worry about having to do a PGD/PUD/PMD walk (like apply_to_page_range does) and we can instead do set_pte. Signed-off-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> ---- [v2: Add comment about alloc_vm_area] [v3: Fix compile error found by 0-day bot]
2014-05-12arm,arm64/xen: introduce HYPERVISOR_suspend()Stefano Stabellini
Introduce HYPERVISOR_suspend() and a few additional empty stubs for Xen arch specific functions called by drivers/xen/manage.c. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2014-05-09arm: xen: export HYPERVISOR_multicall to modules.Ian Campbell
"arm: xen: implement multicall hypercall support." forgot to do this. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
2014-04-24arm: xen: implement multicall hypercall support.Ian Campbell
As part of this make the usual change to xen_ulong_t in place of unsigned long. This change has no impact on x86. The Linux definition of struct multicall_entry.result differs from the Xen definition, I think for good reasons, and used a long rather than an unsigned long. Therefore introduce a xen_long_t, which is a long on x86 architectures and a signed 64-bit integer on ARM. Use uint32_t nr_calls on x86 for consistency with the ARM definition. Build tested on amd64 and i386 builds. Runtime tested on ARM. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2014-03-18xen/grant-table: Refactor gnttab_[un]map_refs to avoid m2p_overrideZoltan Kiss
The grant mapping API does m2p_override unnecessarily: only gntdev needs it, for blkback and future netback patches it just cause a lock contention, as those pages never go to userspace. Therefore this series does the following: - the bulk of the original function (everything after the mapping hypercall) is moved to arch-dependent set/clear_foreign_p2m_mapping - the "if (xen_feature(XENFEAT_auto_translated_physmap))" branch goes to ARM - therefore the ARM function could be much smaller, the m2p_override stubs could be also removed - on x86 the set_phys_to_machine calls were moved up to this new funcion from m2p_override functions - and m2p_override functions are only called when there is a kmap_ops param It also removes a stray space from arch/x86/include/asm/xen/page.h. Signed-off-by: Zoltan Kiss <zoltan.kiss@citrix.com> Suggested-by: Anthony Liguori <aliguori@amazon.com> Suggested-by: David Vrabel <david.vrabel@citrix.com> Suggested-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>