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* cma: make default CMA area size zero for x86Akinobu Mita2014-12-10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | This makes CMA memory area size zero for x86 in default configuration (doesn't change on the other architectures). If default CMA size is zero, DMA_CMA is disabled. It can be enabled by passing cma= to the kernel. This makes less impact on x86. Because there is no mainline driver that requires it for x86, and Peter Hurley reported the performance regression, as this is trying to drive _all_ dma mapping allocations through a _very_ small window. Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Reported-by: Peter Hurley <peter@hurleysoftware.com> Cc: Peter Hurley <peter@hurleysoftware.com> Cc: Chuck Ebbert <cebbert.lkml@gmail.com> Cc: Jean Delvare <jdelvare@suse.de> Acked-by: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Don Dutile <ddutile@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* tiny: rename ENABLE_DEV_COREDUMP to ALLOW_DEV_COREDUMPJohannes Berg2014-11-07
| | | | | | | | | | | | | The ENABLE_DEV_COREDUMP option is misleading as it implies that it gets the framework enabled, this isn't true it just allows it to get enabled if a driver needs it. Rename it to ALLOW_DEV_COREDUMP to better capture its semantics. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org> Acked-by: Aristeu Rozanski <aris@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* tiny: reverse logic for DISABLE_DEV_COREDUMPAristeu Rozanski2014-11-07
| | | | | | | | | | | | | | | | | | It's desirable for allnconfig and tinyconfig targets to result in the least amount of code possible. DISABLE_DEV_COREDUMP exists as a way to switch off DEV_COREDUMP regardless if any drivers select WANT_DEV_COREDUMP. This patch renames the option to ENABLE_DEV_COREDUMP and setting it to 'n' (as in allnconfig or tinyconfig) will effectively disable device coredump. Cc: Josh Triplett <josh@joshtriplett.org> Reviewed-by: Josh Triplett <josh@joshtriplett.org> Signed-off-by: Aristeu Rozanski <arozansk@redhat.com> Reviewed-by: Johannes Berg <johannes@sipsolutions.net> Acked-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* CMA: document cma=0Jean Delvare2014-10-09
| | | | | | | | | | | | | | | It isn't obvious that CMA can be disabled on the kernel's command line, so document it. Signed-off-by: Jean Delvare <jdelvare@suse.de> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Akinobu Mita <akinobu.mita@gmail.com> Cc: Chuck Ebbert <cebbert.lkml@gmail.com> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* device coredump: add new device coredump classJohannes Berg2014-09-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Many devices run firmware and/or complex hardware, and most of that can have bugs. When it misbehaves, however, it is often much harder to debug than software running on the host. Introduce a "device coredump" mechanism to allow dumping internal device/firmware state through a generalized mechanism. As devices are different and information needed can vary accordingly, this doesn't prescribe a file format - it just provides mechanism to get data to be able to capture it in a generalized way (e.g. in distributions.) The dumped data will be readable in sysfs in the virtual device's data file under /sys/class/devcoredump/devcd*/. Writing to it will free the data and remove the device, as does a 5-minute timeout. Note that generalized capturing of such data may result in privacy issues, so users generally need to be involved. In order to allow certain users/system integrators/... to disable the feature at all, introduce a Kconfig option to override the drivers that would like to have the feature. For now, this provides two ways of dumping data: 1) with a vmalloc'ed area, that is then given to the subsystem and freed after retrieval or timeout 2) with a generalized reader/free function method We could/should add more options, e.g. a list of pages, since the vmalloc area is very limited on some architectures. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* CMA: generalize CMA reserved area management functionalityJoonsoo Kim2014-08-06
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, there are two users on CMA functionality, one is the DMA subsystem and the other is the KVM on powerpc. They have their own code to manage CMA reserved area even if they looks really similar. From my guess, it is caused by some needs on bitmap management. KVM side wants to maintain bitmap not for 1 page, but for more size. Eventually it use bitmap where one bit represents 64 pages. When I implement CMA related patches, I should change those two places to apply my change and it seem to be painful to me. I want to change this situation and reduce future code management overhead through this patch. This change could also help developer who want to use CMA in their new feature development, since they can use CMA easily without copying & pasting this reserved area management code. In previous patches, we have prepared some features to generalize CMA reserved area management and now it's time to do it. This patch moves core functions to mm/cma.c and change DMA APIs to use these functions. There is no functional change in DMA APIs. Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Acked-by: Michal Nazarewicz <mina86@mina86.com> Acked-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Acked-by: Minchan Kim <minchan@kernel.org> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Cc: Alexander Graf <agraf@suse.de> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Cc: Gleb Natapov <gleb@kernel.org> Acked-by: Marek Szyprowski <m.szyprowski@samsung.com> Tested-by: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* firmware loader: allow disabling of udev as firmware loaderTakashi Iwai2014-07-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [The patch was originally proposed by Tom Gundersen, and rewritten afterwards by me; most of changelogs below borrowed from Tom's original patch -- tiwai] Currently (at least) the dell-rbu driver selects FW_LOADER_USER_HELPER, which means that distros can't really stop loading firmware through udev without breaking other users (though some have). Ideally we would remove/disable the udev firmware helper in both the kernel and in udev, but if we were to disable it in udev and not the kernel, the result would be (seemingly) hung kernels as no one would be around to cancel firmware requests. This patch allows udev firmware loading to be disabled while still allowing non-udev firmware loading, as done by the dell-rbu driver, to continue working. This is achieved by only using the fallback mechanism when the uevent is suppressed. The patch renames the user-selectable Kconfig from FW_LOADER_USER_HELPER to FW_LOADER_USER_HELPER_FALLBACK, and the former is reverse-selected by the latter or the drivers that need userhelper like dell-rbu. Also, the "default y" is removed together with this change, since it's been deprecated in udev upstream, thus rather better to disable it nowadays. Tested with FW_LOADER_USER_HELPER=n LATTICE_ECP3_CONFIG=y DELL_RBU=y and udev without the firmware loading support, but I don't have the hardware to test the lattice/dell drivers, so additional testing would be appreciated. Reviewed-by: Tom Gundersen <teg@jklm.no> Cc: Ming Lei <ming.lei@canonical.com> Cc: Abhay Salunke <Abhay_Salunke@dell.com> Cc: Stefan Roese <sr@denx.de> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Kay Sievers <kay@vrfy.org> Tested-by: Balaji Singh <B_B_Singh@DELL.com> Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* fence: dma-buf cross-device synchronization (v18)Maarten Lankhorst2014-07-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A fence can be attached to a buffer which is being filled or consumed by hw, to allow userspace to pass the buffer without waiting to another device. For example, userspace can call page_flip ioctl to display the next frame of graphics after kicking the GPU but while the GPU is still rendering. The display device sharing the buffer with the GPU would attach a callback to get notified when the GPU's rendering-complete IRQ fires, to update the scan-out address of the display, without having to wake up userspace. A driver must allocate a fence context for each execution ring that can run in parallel. The function for this takes an argument with how many contexts to allocate: + fence_context_alloc() A fence is transient, one-shot deal. It is allocated and attached to one or more dma-buf's. When the one that attached it is done, with the pending operation, it can signal the fence: + fence_signal() To have a rough approximation whether a fence is fired, call: + fence_is_signaled() The dma-buf-mgr handles tracking, and waiting on, the fences associated with a dma-buf. The one pending on the fence can add an async callback: + fence_add_callback() The callback can optionally be cancelled with: + fence_remove_callback() To wait synchronously, optionally with a timeout: + fence_wait() + fence_wait_timeout() When emitting a fence, call: + trace_fence_emit() To annotate that a fence is blocking on another fence, call: + trace_fence_annotate_wait_on(fence, on_fence) A default software-only implementation is provided, which can be used by drivers attaching a fence to a buffer when they have no other means for hw sync. But a memory backed fence is also envisioned, because it is common that GPU's can write to, or poll on some memory location for synchronization. For example: fence = custom_get_fence(...); if ((seqno_fence = to_seqno_fence(fence)) != NULL) { dma_buf *fence_buf = seqno_fence->sync_buf; get_dma_buf(fence_buf); ... tell the hw the memory location to wait ... custom_wait_on(fence_buf, seqno_fence->seqno_ofs, fence->seqno); } else { /* fall-back to sw sync * / fence_add_callback(fence, my_cb); } On SoC platforms, if some other hw mechanism is provided for synchronizing between IP blocks, it could be supported as an alternate implementation with it's own fence ops in a similar way. enable_signaling callback is used to provide sw signaling in case a cpu waiter is requested or no compatible hardware signaling could be used. The intention is to provide a userspace interface (presumably via eventfd) later, to be used in conjunction with dma-buf's mmap support for sw access to buffers (or for userspace apps that would prefer to do their own synchronization). v1: Original v2: After discussion w/ danvet and mlankhorst on #dri-devel, we decided that dma-fence didn't need to care about the sw->hw signaling path (it can be handled same as sw->sw case), and therefore the fence->ops can be simplified and more handled in the core. So remove the signal, add_callback, cancel_callback, and wait ops, and replace with a simple enable_signaling() op which can be used to inform a fence supporting hw->hw signaling that one or more devices which do not support hw signaling are waiting (and therefore it should enable an irq or do whatever is necessary in order that the CPU is notified when the fence is passed). v3: Fix locking fail in attach_fence() and get_fence() v4: Remove tie-in w/ dma-buf.. after discussion w/ danvet and mlankorst we decided that we need to be able to attach one fence to N dma-buf's, so using the list_head in dma-fence struct would be problematic. v5: [ Maarten Lankhorst ] Updated for dma-bikeshed-fence and dma-buf-manager. v6: [ Maarten Lankhorst ] I removed dma_fence_cancel_callback and some comments about checking if fence fired or not. This is broken by design. waitqueue_active during destruction is now fatal, since the signaller should be holding a reference in enable_signalling until it signalled the fence. Pass the original dma_fence_cb along, and call __remove_wait in the dma_fence_callback handler, so that no cleanup needs to be performed. v7: [ Maarten Lankhorst ] Set cb->func and only enable sw signaling if fence wasn't signaled yet, for example for hardware fences that may choose to signal blindly. v8: [ Maarten Lankhorst ] Tons of tiny fixes, moved __dma_fence_init to header and fixed include mess. dma-fence.h now includes dma-buf.h All members are now initialized, so kmalloc can be used for allocating a dma-fence. More documentation added. v9: Change compiler bitfields to flags, change return type of enable_signaling to bool. Rework dma_fence_wait. Added dma_fence_is_signaled and dma_fence_wait_timeout. s/dma// and change exports to non GPL. Added fence_is_signaled and fence_enable_sw_signaling calls, add ability to override default wait operation. v10: remove event_queue, use a custom list, export try_to_wake_up from scheduler. Remove fence lock and use a global spinlock instead, this should hopefully remove all the locking headaches I was having on trying to implement this. enable_signaling is called with this lock held. v11: Use atomic ops for flags, lifting the need for some spin_lock_irqsaves. However I kept the guarantee that after fence_signal returns, it is guaranteed that enable_signaling has either been called to completion, or will not be called any more. Add contexts and seqno to base fence implementation. This allows you to wait for less fences, by testing for seqno + signaled, and then only wait on the later fence. Add FENCE_TRACE, FENCE_WARN, and FENCE_ERR. This makes debugging easier. An CONFIG_DEBUG_FENCE will be added to turn off the FENCE_TRACE spam, and another runtime option can turn it off at runtime. v12: Add CONFIG_FENCE_TRACE. Add missing documentation for the fence->context and fence->seqno members. v13: Fixup CONFIG_FENCE_TRACE kconfig description. Move fence_context_alloc to fence. Simplify fence_later. Kill priv member to fence_cb. v14: Remove priv argument from fence_add_callback, oops! v15: Remove priv from documentation. Explicitly include linux/atomic.h. v16: Add trace events. Import changes required by android syncpoints. v17: Use wake_up_state instead of try_to_wake_up. (Colin Cross) Fix up commit description for seqno_fence. (Rob Clark) v18: Rename release_fence to fence_release. Move to drivers/dma-buf/. Rename __fence_is_signaled and __fence_signal to *_locked. Rename __fence_init to fence_init. Make fence_default_wait return a signed long, and fix wait ops too. Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com> #use smp_mb__before_atomic() Acked-by: Sumit Semwal <sumit.semwal@linaro.org> Acked-by: Daniel Vetter <daniel@ffwll.ch> Reviewed-by: Rob Clark <robdclark@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* cma: increase CMA_ALIGNMENT upper limit to 12Marc Carino2014-06-04
| | | | | | | | | | | | Some systems require a larger maximum PAGE_SIZE order for CMA allocations. To accommodate such systems, increase the upper-bound of the CMA_ALIGNMENT range to 12 (which ends up being 16MB on systems with 4K pages). Signed-off-by: Marc Carino <marc.ceeeee@gmail.com> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* kobject: Make support for uevent_helper optional.Michael Marineau2014-04-25
| | | | | | | | | Support for uevent_helper, aka hotplug, is not required on many systems these days but it can still be enabled via sysfs or sysctl. Reported-by: Darren Shepherd <darren.s.shepherd@gmail.com> Signed-off-by: Michael Marineau <mike@marineau.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* x86: align x86 arch with generic CPU modalias handlingArd Biesheuvel2014-02-18
| | | | | | | | | | | | | | The x86 CPU feature modalias handling existed before it was reimplemented generically. This patch aligns the x86 handling so that it (a) reuses some more code that is now generic; (b) uses the generic format for the modalias module metadata entry, i.e., it now uses 'cpu:type:x86,venVVVVfamFFFFmodMMMM:feature:,XXXX,YYYY' instead of the 'x86cpu:vendor:VVVV:family:FFFF:model:MMMM:feature:,XXXX,YYYY' that was used before. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Acked-by: H. Peter Anvin <hpa@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* cpu: add generic support for CPU feature based module autoloadingArd Biesheuvel2014-02-18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch adds support for advertising optional CPU features over udev using the modalias, and for declaring compatibility with/dependency upon such a feature in a module. The mapping between feature numbers and actual features should be provided by the architecture in a file called <asm/cpufeature.h> which exports the following functions/macros: - cpu_feature(FEAT), a preprocessor macro that maps token FEAT to a numeric index; - bool cpu_have_feature(n), returning whether this CPU has support for feature #n; - MAX_CPU_FEATURES, an upper bound for 'n' in the previous function. The feature can then be enabled by setting CONFIG_GENERIC_CPU_AUTOPROBE for the architecture. For instance, a module that registers its module init function using module_cpu_feature_match(FEAT_X, module_init_function) will be probed automatically when the CPU's support for the 'FEAT_X' feature is advertised over udev, and will only allow the module to be loaded by hand if the 'FEAT_X' feature is supported. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* drivers: fix typo in DEVTMPFS_MOUNT Kconfig help textEmilio López2013-12-19
| | | | | | | rootfs was missing its f. Signed-off-by: Emilio López <emilio@elopez.com.ar> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
* Merge remote-tracking branch 'cmadma/for-v3.12-cma-dma' into kvm-ppc-nextAlexander Graf2013-07-08
|\ | | | | | | Add prerequisite patch for CMA RMA allocation patches
| * mm/cma: Move dma contiguous changes into a seperate configAneesh Kumar K.V2013-07-02
| | | | | | | | | | | | | | | | | | | | | | | | We want to use CMA for allocating hash page table and real mode area for PPC64. Hence move DMA contiguous related changes into a seperate config so that ppc64 can enable CMA without requiring DMA contiguous. Acked-by: Michal Nazarewicz <mina86@mina86.com> Acked-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> [removed defconfig changes] Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
* | Finally eradicate CONFIG_HOTPLUGStephen Rothwell2013-06-03
|/ | | | | | | | | | | | | | | | | | | 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>
* firmware: Make user-mode helper optionalTakashi Iwai2013-02-03
| | | | | | | | | | | | This patch adds a new kconfig, CONFIG_FW_LOADER_USER_HELPER, and guards the user-helper codes in firmware_class.c with ifdefs. Yeah, yeah, there are lots of ifdefs in this patch. The further clean-up with code shuffling follows in the next. Acked-by: Ming Lei <ming.lei@canonical.com> Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Merge 3.7-rc3 into driver-core-nextGreg Kroah-Hartman2012-10-29
|\ | | | | | | | | | | | | This pulls in the various driver core changes that were in 3.7-rc3 into the driver-core-next branch. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * drivers: cma: Fix wrong CMA selected region size default valueLaurent Pinchart2012-10-23
| | | | | | | | | | | | | | | | | | Kconfig lists CMA_SIZE_SEL_ABSOLUTE as the default value fo the CMA selected region size, but that option isn't available in the defined choices. Set the default to CMA_SIZE_SEL_MBYTES instead. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
* | drivers/base: remove CONFIG_EXPERIMENTALKees Cook2012-10-25
|/ | | | | | | | | | This config item has not carried much meaning for a while now and is almost always enabled by default. As agreed during the Linux kernel summit, remove it. CC: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* mm: factor out memory isolate functionsMinchan Kim2012-07-31
| | | | | | | | | | | | | | | | | | mm/page_alloc.c has some memory isolation functions but they are used only when we enable CONFIG_{CMA|MEMORY_HOTPLUG|MEMORY_FAILURE}. So let's make it configurable by new CONFIG_MEMORY_ISOLATION so that it can reduce binary size and we can check it simple by CONFIG_MEMORY_ISOLATION, not if defined CONFIG_{CMA|MEMORY_HOTPLUG|MEMORY_FAILURE}. Signed-off-by: Minchan Kim <minchan@kernel.org> Cc: Andi Kleen <andi@firstfloor.org> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Michal Hocko <mhocko@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* drivers: add Contiguous Memory AllocatorMarek Szyprowski2012-05-21
| | | | | | | | | | | | | | | | | | | | | | | | | | The Contiguous Memory Allocator is a set of helper functions for DMA mapping framework that improves allocations of contiguous memory chunks. CMA grabs memory on system boot, marks it with MIGRATE_CMA migrate type and gives back to the system. Kernel is allowed to allocate only movable pages within CMA's managed memory so that it can be used for example for page cache when DMA mapping do not use it. On dma_alloc_from_contiguous() request such pages are migrated out of CMA area to free required contiguous block and fulfill the request. This allows to allocate large contiguous chunks of memory at any time assuming that there is enough free memory available in the system. This code is heavily based on earlier works by Michal Nazarewicz. Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com> Signed-off-by: Michal Nazarewicz <mina86@mina86.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Tested-by: Rob Clark <rob.clark@linaro.org> Tested-by: Ohad Ben-Cohen <ohad@wizery.com> Tested-by: Benjamin Gaignard <benjamin.gaignard@linaro.org> Tested-by: Robert Nelson <robertcnelson@gmail.com> Tested-by: Barry Song <Baohua.Song@csr.com>
* drivers/base: add bus for System-on-Chip devicesLee Jones2012-02-10
| | | | | | | | | | | | | | | | Traditionally, any System-on-Chip based platform creates a flat list of platform_devices directly under /sys/devices/platform. In order to give these some better structure, this introduces a new bus type for soc_devices that are registered with the new soc_device_register() function. All devices that are on the same chip should then be registered as child devices of the soc device. The soc bus also exports a few standardised device attributes which allow user space to query the specific type of soc. Signed-off-by: Lee Jones <lee.jones@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* dma-buf: drop option text so users don't select it.Dave Airlie2012-01-13
| | | | | | This is going to be used by other subsystems so they should select it. Signed-off-by: Dave Airlie <airlied@redhat.com>
* cpu: Register a generic CPU device on architectures that currently do notBen Hutchings2012-01-11
| | | | | | | | | | | | | frv, h8300, m68k, microblaze, openrisc, score, um and xtensa currently do not register a CPU device. Add the config option GENERIC_CPU_DEVICES which causes a generic CPU device to be registered for each present CPU, and make all these architectures select it. Richard Weinberger <richard@nod.at> covered UML and suggested using per_cpu. Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* dma-buf: mark EXPERIMENTAL for 1st release.Sumit Semwal2012-01-06
| | | | | | | | | | Mark dma-buf buffer sharing API as EXPERIMENTAL for first release. We will remove this in later versions, once it gets smoothed out and has more users. Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org> Signed-off-by: Sumit Semwal <sumit.semwal@ti.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
* dma-buf: Introduce dma buf