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2012-07-16driver core: fix shutdown races with probe/remove(v3)Ming Lei
Firstly, .shutdown callback may touch a uninitialized hardware if dev->driver is set and .probe is not completed. Secondly, device_shutdown() may dereference a null pointer to cause oops when dev->driver is cleared after it has been checked in device_shutdown(). So just hold device lock and its parent lock(if it has) to fix the races. Cc: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Ming Lei <ming.lei@canonical.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-07-14get rid of kern_path_parent()Al Viro
all callers want the same thing, actually - a kinda-sorta analog of kern_path_create(). I.e. they want parent vfsmount/dentry (with ->i_mutex held, to make sure the child dentry is still their child) + the child dentry. Signed-off-by Al Viro <viro@zeniv.linux.org.uk>
2012-07-12PM / Sleep: Fix build warning in sysfs.c for CONFIG_PM_SLEEP unsetRafael J. Wysocki
The power/async device sysfs attribute is only used if both CONFIG_PM_ADVANCED_DEBUG and CONFIG_PM_SLEEP are set, but the code implementing it doesn't depend on CONFIG_PM_SLEEP. As a result, a build warning appears if CONFIG_PM_ADVANCED_DEBUG is set and CONFIG_PM_SLEEP is not set. Fix it by adding a #ifdef CONFIG_PM_SLEEP around the code in question. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-07-12PM / Domains: Fix build warning for CONFIG_PM_RUNTIME unsetRafael J. Wysocki
The functions genpd_save_dev() and genpd_restore_dev() are not used for CONFIG_PM_RUNTIME unset, so move them under an appropriate #ifdef. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-07-11PM / Domains: Replace plain integer with NULL pointer in domain.c fileSachin Kamat
Fixes the following sparse warning: drivers/base/power/domain.c:1679:55: warning: Using plain integer as NULL pointer Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-07-10PM / Domains: Add missing static storage class specifier in domain.c fileSachin Kamat
Fixes the folloiwng sparse warning: drivers/base/power/domain.c:149:5: warning: symbol '__pm_genpd_poweron' was not declared. Should it be static? Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-07-10PM / cpuidle: System resume hang fix with cpuidlePreeti U Murthy
On certain bios, resume hangs if cpus are allowed to enter idle states during suspend [1]. This was fixed in apci idle driver [2].But intel_idle driver does not have this fix. Thus instead of replicating the fix in both the idle drivers, or in more platform specific idle drivers if needed, the more general cpuidle infrastructure could handle this. A suspend callback in cpuidle_driver could handle this fix. But a cpuidle_driver provides only basic functionalities like platform idle state detection capability and mechanisms to support entry and exit into CPU idle states. All other cpuidle functions are found in the cpuidle generic infrastructure for good reason that all cpuidle drivers, irrepective of their platforms will support these functions. One option therefore would be to register a suspend callback in cpuidle which handles this fix. This could be called through a PM_SUSPEND_PREPARE notifier. But this is too generic a notfier for a driver to handle. Also, ideally the job of cpuidle is not to handle side effects of suspend. It should expose the interfaces which "handle cpuidle 'during' suspend" or any other operation, which the subsystems call during that respective operation. The fix demands that during suspend, no cpus should be allowed to enter deep C-states. The interface cpuidle_uninstall_idle_handler() in cpuidle ensures that. Not just that it also kicks all the cpus which are already in idle out of their idle states which was being done during cpu hotplug through a CPU_DYING_FROZEN callbacks. Now the question arises about when during suspend should cpuidle_uninstall_idle_handler() be called. Since we are dealing with drivers it seems best to call this function during dpm_suspend(). Delaying the call till dpm_suspend_noirq() does no harm, as long as it is before cpu_hotplug_begin() to avoid race conditions with cpu hotpulg operations. In dpm_suspend_noirq(), it would be wise to place this call before suspend_device_irqs() to avoid ugly interactions with the same. Ananlogously, during resume. References: [1] https://bugs.launchpad.net/ubuntu/+source/linux/+bug/674075. [2] http://marc.info/?l=linux-pm&m=133958534231884&w=2 Reported-and-tested-by: Dave Hansen <dave@linux.vnet.ibm.com> Signed-off-by: Preeti U Murthy <preeti@linux.vnet.ibm.com> Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-07-06regmap: Add hook for printk logging for debugging during early initMark Brown
Sometimes for failures during very early init the trace infrastructure isn't available early enough to be used. For this sort of problem defining LOG_DEVICE will add printks for basic register I/O on a specific device, allowing trace to be extracted when the trace system doesn't come up early enough to work with. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-07-05PM / Domains: Allow device callbacks to be added at any timeRafael J. Wysocki
Make it possible to modify device callbacks used by the generic PM domains core code at any time, not only after the device has been added to a domain. This will allow device drivers to provide their own device PM domain callbacks even if they are registered before adding the devices to PM domains. For this purpose, use the observation that the struct generic_pm_domain_data object containing the relevant callback pointers may be allocated by pm_genpd_add_callbacks() and the callbacks may be set before __pm_genpd_add_device() is run for the given device. This object will then be used by __pm_genpd_add_device(), but it has to be protected from premature removal by reference counting. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-07-05PM / Domains: Add device domain data reference counterRafael J. Wysocki
Add a mechanism for counting references to the struct generic_pm_domain_data object pointed to by dev->power.subsys_data->domain_data if the device in question belongs to a generic PM domain. This change is necessary for a subsequent patch making it possible to allocate that object from within pm_genpd_add_callbacks(), so that drivers can attach their PM domain device callbacks to devices before those devices are added to PM domains. This patch has been tested on the SH7372 Mackerel board. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-07-05Merge v3.5-rc5 into driver-core-nextGreg Kroah-Hartman
This picks up the big printk fixes, and resolves a merge issue with: drivers/extcon/extcon_gpio.c Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-07-03PM / Domains: Add preliminary support for cpuidle, v2Rafael J. Wysocki
On some systems there are CPU cores located in the same power domains as I/O devices. Then, power can only be removed from the domain if all I/O devices in it are not in use and the CPU core is idle. Add preliminary support for that to the generic PM domains framework. First, the platform is expected to provide a cpuidle driver with one extra state designated for use with the generic PM domains code. This state should be initially disabled and its exit_latency value should be set to whatever time is needed to bring up the CPU core itself after restoring power to it, not including the domain's power on latency. Its .enter() callback should point to a procedure that will remove power from the domain containing the CPU core at the end of the CPU power transition. The remaining characteristics of the extra cpuidle state, referred to as the "domain" cpuidle state below, (e.g. power usage, target residency) should be populated in accordance with the properties of the hardware. Next, the platform should execute genpd_attach_cpuidle() on the PM domain containing the CPU core. That will cause the generic PM domains framework to treat that domain in a special way such that: * When all devices in the domain have been suspended and it is about to be turned off, the states of the devices will be saved, but power will not be removed from the domain. Instead, the "domain" cpuidle state will be enabled so that power can be removed from the domain when the CPU core is idle and the state has been chosen as the target by the cpuidle governor. * When the first I/O device in the domain is resumed and __pm_genpd_poweron(() is called for the first time after power has been removed from the domain, the "domain" cpuidle state will be disabled to avoid subsequent surprise power removals via cpuidle. The effective exit_latency value of the "domain" cpuidle state depends on the time needed to bring up the CPU core itself after restoring power to it as well as on the power on latency of the domain containing the CPU core. Thus the "domain" cpuidle state's exit_latency has to be recomputed every time the domain's power on latency is updated, which may happen every time power is restored to the domain, if the measured power on latency is greater than the latency stored in the corresponding generic_pm_domain structure. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Reviewed-by: Kevin Hilman <khilman@ti.com>
2012-07-01PM / Domains: Do not stop devices after restoring their statesRafael J. Wysocki
While resuming a device belonging to a PM domain, pm_genpd_runtime_resume() calls __pm_genpd_restore_device() to restore its state, if necessary. The latter starts the device, using genpd_start_dev(), restores its state, using genpd_restore_dev(), and then stops it, using genpd_stop_dev(). However, this last operation is not necessary, because the device is supposed to be operational after pm_genpd_runtime_resume() has returned and because of it pm_genpd_runtime_resume() has to call genpd_start_dev() once again for the "restored" device, which is inefficient. To make things more efficient, remove the call to genpd_stop_dev() from __pm_genpd_restore_device() and the direct call to genpd_start_dev() from pm_genpd_runtime_resume(). [Of course, genpd_start_dev() still has to be called by it for devices with the power.irq_safe flag set, because __pm_genpd_restore_device() is not executed for them.] This change has been tested on the SH7372 Mackerel board. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-07-01PM / Domains: Use subsystem runtime suspend/resume callbacks by defaultRafael J. Wysocki
Currently, the default "save state" and "restore state" routines for generic PM domains, pm_genpd_default_save_state() and pm_genpd_default_restore_state(), respectively, only use runtime PM callbacks provided by device drivers, but in general those callbacks need not provide the entire necessary functionality. Namely, in general it may be necessary to execute subsystem (i.e. device type, device class or bus type) callbacks that will carry out all of the necessary operations. For this reason, modify pm_genpd_default_save_state() and pm_genpd_default_restore_state() to execute subsystem callbacks, if they are provided, and fall back to driver callbacks otherwise. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-07-01PM / Sleep: Separate printing suspend times from initcall_debugRafael J. Wysocki
Change the behavior of the newly introduced /sys/power/pm_print_times attribute so that its initial value depends on initcall_debug, but setting it to 0 will cause device suspend/resume times not to be printed, even if initcall_debug has been set. This way, the people who use initcall_debug for reasons other than PM debugging will be able to switch the suspend/resume times printing off, if need be. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-07-01PM / Sleep: add knob for printing device resume timesSameer Nanda
Added a new knob called /sys/power/pm_print_times. Setting it to 1 enables printing of time taken by devices to suspend and resume. Setting it to 0 disables this printing (unless overridden by initcall_debug kernel command line option). Signed-off-by: Sameer Nanda <snanda@chromium.org> Acked-by: Greg KH <gregkh@linuxfoundation.org> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-06-24PM / Sleep: Prevent waiting forever on asynchronous suspend after abortMandeep Singh Baines
__device_suspend() must always send a completion. Otherwise, parent devices will wait forever. Commit 1e2ef05b, "PM: Limit race conditions between runtime PM and system sleep (v2)", introduced a regression by short-circuiting the complete_all() for certain error cases. This patch fixes the bug by always signalling a completion. Addresses http://crosbug.com/31972 Tested by injecting an abort. Signed-off-by: Mandeep Singh Baines <msb@chromium.org> Cc: stable@vger.kernel.org Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-06-20Merge tag 'driver-core-3.5-rc4' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core and printk fixes from Greg Kroah-Hartman: "Here are some fixes for 3.5-rc4 that resolve the kmsg problems that people have reported showing up after the printk and kmsg changes went into 3.5-rc1. There are also a smattering of other tiny fixes for the extcon and hyper-v drivers that people have reported. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>" * tag 'driver-core-3.5-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: extcon: max8997: Add missing kfree for info->edev in max8997_muic_remove() extcon: Set platform drvdata in gpio_extcon_probe() and fix irq leak extcon: Fix wrong index in max8997_extcon_cable[] kmsg - kmsg_dump() fix CONFIG_PRINTK=n compilation printk: return -EINVAL if the message len is bigger than the buf size printk: use mutex lock to stop syslog_seq from going wild kmsg - kmsg_dump() use iterator to receive log buffer content vme: change maintainer e-mail address Extcon: Don't try to create duplicate link names driver core: fixup reversed deferred probe order printk: Fix alignment of buf causing crash on ARM EABI Tools: hv: verify origin of netlink connector message
2012-06-19regmap: Fix work_buf switching for page update during virtual range access.Krystian Garbaciak
After page update, orginal work_buf has to be restored regardless of the result. Signed-off-by: Krystian Garbaciak <krystian.garbaciak@diasemi.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-06-17regmap: Add support for register indirect addressing.Krystian Garbaciak
Devices with register paging or indirectly accessed registers can configure register mapping to map those on virtual address range. During access to virtually mapped register range, indirect addressing is processed automatically, in following steps: 1. selector for page or indirect register is updated (when needed); 2. register in data window is accessed. Configuration should provide minimum and maximum register for virtual range, details of selector field for page selection, minimum and maximum register of data window for indirect access. Virtual range registers are managed by cache as well as direct access registers. In order to make indirect access more efficient, selector register should be declared as non-volatile, if possible. struct regmap_config is extended with the following: struct regmap_range_cfg *ranges; unsigned int n_ranges; [Also reordered debugfs init to later on since the cleanup code was conflicting with the new cleanup code for ranges anyway -- broonie] Signed-off-by: Krystian Garbaciak <krystian.garbaciak@diasemi.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-06-17regmap: Move lock out from internal function _regmap_update_bits().Krystian Garbaciak
Locks are moved to regmap_update_bits(), which allows to reenter internal function _regmap_update_bits() from inside of regmap read/write routines. Signed-off-by: Krystian Garbaciak <krystian.garbaciak@diasemi.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-06-14driver core: fix some kernel-doc warnings in dma*.cRandy Dunlap
Fix kernel-doc warnings in drivers/base/dma*.c: Warning(drivers/base/dma-buf.c:498): No description found for parameter 'vaddr' Warning(drivers/base/dma-coherent.c:199): No description found for parameter 'ret' Signed-off-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-13device-core: Ensure drvdata = NULL when no driver is boundHans de Goede
1) drvdata is for a driver to store a pointer to driver specific data 2) If no driver is bound, there is no driver specific data associated with the device 3) Thus logically drvdata should be NULL if no driver is bound. But many drivers don't clear drvdata on device_release, or set drvdata early on in probe and leave it set on probe error. Both of which results in a dangling pointer in drvdata. This patch enforce for drvdata to be NULL after device_release or on probe failure. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-13driver core: fixup reversed deferred probe orderKuninori Morimoto
If driver requests probe deferral, it will be added to deferred_probe_pending_list by driver_deferred_probe_add(), but, it used list_add(). Because of that, deferred probe will be run as reversed order. This patch uses list_add_tail(), and solved this issue. Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-13regmap: mmio: Staticize regmap_mmio_gen_context()Axel Lin
regmap_mmio_gen_context() is only used in regmap-mmio.c. Thus make it static. Signed-off-by: Axel Lin <axel.lin@gmail.com> Acked-by: Stephen Warren <swarren@wwwdotorg.org> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-06-11driver core: always handle dpm_orderRabin Vincent
If !dev->class, device_move() does not respect the dpm_order. Fix it to do so. Acked-by: Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by: Rabin Vincent <rabin.vincent@stericsson.com> Reviewed-by: Srinidhi Kasagar <srinidhi.kasagar@stericsson.com> [Fixed a small dangling label compile warning] Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-08regmap: Export regmap_reinit_cache()Mark Brown
It's supposed to be there for drivers. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-06-05regmap: Implement support for wake IRQsMark Brown
Allow chips to provide a bank of registers for controlling the wake state in a similar fashion to the masks and propagate the wake count to the parent interrupt controller. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-06-05regmap: Don't try to map non-existant IRQsMark Brown
If the driver supplied an empty entry in the array of IRQs then return an error rather than trying to do the mapping. This is intended for use with handling chip variants and similar situations. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-06-03regmap: Constify regmap_irq_chipMark Brown
We should never be modifying it and it lets drivers declare it const. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-06-03regmap: Fix the size calculation for map->format.buf_sizeFabio Estevam
The word to be transmitted/received via regmap is composed by the following parts: config->reg_bits config->val_bits config->pad_bits ,so the total size should be calculated by summing up the number of bits of each element and using a DIV_ROUND_UP to return the number of bytes. Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-06-03regmap: clean up debugfs if regmap_init failsStephen Warren
If debugfs isn't cleaned up, stale files will be left in the filesystem which will cause an OOPS when accessed the first time, and hang the accessing application when accessed again, presumably due to some lock being left held. Signed-off-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-06-03regmap: mmio: request native endian formattingStephen Warren
This will avoid the regmap core converting all addresses and values into big endian, only for the mmio bus driver to have to convert them back to native endian. Signed-off-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-06-03regmap: allow busses to request formatting with specific endiannessStephen Warren
Add a field to struct regmap_bus that allows bus drivers to request that register addresses and values be formatted with a specific endianness. The default endianness is unchanged from current operation: Big. Implement native endian formatting/parsing for 16- and 32-bit values. This will be enough to support regmap-mmio.c. Signed-off-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-06-01Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs changes from Al Viro. "A lot of misc stuff. The obvious groups: * Miklos' atomic_open series; kills the damn abuse of ->d_revalidate() by NFS, which was the major stumbling block for all work in that area. * ripping security_file_mmap() and dealing with deadlocks in the area; sanitizing the neighborhood of vm_mmap()/vm_munmap() in general. * ->encode_fh() switched to saner API; insane fake dentry in mm/cleancache.c gone. * assorted annotations in fs (endianness, __user) * parts of Artem's ->s_dirty work (jff2 and reiserfs parts) * ->update_time() work from Josef. * other bits and pieces all over the place. Normally it would've been in two or three pull requests, but signal.git stuff had eaten a lot of time during this cycle ;-/" Fix up trivial conflicts in Documentation/filesystems/vfs.txt (the 'truncate_range' inode method was removed by the VM changes, the VFS update adds an 'update_time()' method), and in fs/btrfs/ulist.[ch] (due to sparse fix added twice, with other changes nearby). * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (95 commits) nfs: don't open in ->d_revalidate vfs: retry last component if opening stale dentry vfs: nameidata_to_filp(): don't throw away file on error vfs: nameidata_to_filp(): inline __dentry_open() vfs: do_dentry_open(): don't put filp vfs: split __dentry_open() vfs: do_last() common post lookup vfs: do_last(): add audit_inode before open vfs: do_last(): only return EISDIR for O_CREAT vfs: do_last(): check LOOKUP_DIRECTORY vfs: do_last(): make ENOENT exit RCU safe vfs: make follow_link check RCU safe vfs: do_last(): use inode variable vfs: do_last(): inline walk_component() vfs: do_last(): make exit RCU safe vfs: split do_lookup() Btrfs: move over to use ->update_time fs: introduce inode operation ->update_time reiserfs: get rid of resierfs_sync_super reiserfs: mark the superblock as dirty a bit later ...
2012-05-30i2c: Split I2C_M_NOSTART support out of I2C_FUNC_PROTOCOL_MANGLINGMark Brown
Since there are uses for I2C_M_NOSTART which are much more sensible and standard than most of the protocol mangling functionality (the main one being gather writes to devices where something like a register address needs to be inserted before a block of data) create a new I2C_FUNC_NOSTART for this feature and update all the users to use it. Also strengthen the disrecommendation of the protocol mangling while we're at it. In the case of regmap-i2c we remove the requirement for mangling as I2C_M_NOSTART is the only mangling feature which is being used. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Acked-by: Wolfram Sang <w.sang@pengutronix.de> Signed-off-by: Jean Delvare <khali@linux-fr.org>
2012-05-29mode_t whack-a-mole: ->is_visible() returns umode_t...Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-05-29mm: fix off-by-one bug in print_nodes_state()Ryota Ozaki
/sys/devices/system/node/{online,possible} outputs a garbage byte because print_nodes_state() returns content size + 1. To fix the bug, the patch changes the use of cpuset_sprintf_cpulist to follow the use at other places, which is clearer and safer. This bug was introduced in v2.6.24 (commit bde631a51876: "mm: add node states sysfs class attributeS"). Signed-off-by: Ryota Ozaki <ozaki.ryota@gmail.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-25Merge tag 'tag-for-linus-3.5' of ↵Linus Torvalds
git://git.linaro.org/people/sumitsemwal/linux-dma-buf Pull dma-buf updates from Sumit Semwal: "Here's the first signed-tag pull request for dma-buf framework. It includes the following key items: - mmap support - vmap support - related documentation updates These are needed by various drivers to allow mmap/vmap of dma-buf shared buffers. Dave Airlie has some prime patches dependent on the vmap pull as well." * tag 'tag-for-linus-3.5' of git://git.linaro.org/people/sumitsemwal/linux-dma-buf: dma-buf: add initial vmap documentation dma-buf: minor documentation fixes. dma-buf: add vmap interface dma-buf: mmap support
2012-05-25Merge branch 'for-linus' of ↵Linus Torvalds
git://git.linaro.org/people/mszyprowski/linux-dma-mapping Pull CMA and ARM DMA-mapping updates from Marek Szyprowski: "These patches contain two major updates for DMA mapping subsystem (mainly for ARM architecture). First one is Contiguous Memory Allocator (CMA) which makes it possible for device drivers to allocate big contiguous chunks of memory after the system has booted. The main difference from the similar frameworks is the fact that CMA allows to transparently reuse the memory region reserved for the big chunk allocation as a system memory, so no memory is wasted when no big chunk is allocated. Once the alloc request is issued, the framework migrates system pages to create space for the required big chunk of physically contiguous memory. For more information one can refer to nice LWN articles: - 'A reworked contiguous memory allocator': http://lwn.net/Articles/447405/ - 'CMA and ARM': http://lwn.net/Articles/450286/ - 'A deep dive into CMA': http://lwn.net/Articles/486301/ - and the following thread with the patches and links to all previous versions: https://lkml.org/lkml/2012/4/3/204 The main client for this new framework is ARM DMA-mapping subsystem. The second part provides a complete redesign in ARM DMA-mapping subsystem. The core implementation has been changed to use common struct dma_map_ops based infrastructure with the recent updates for new dma attributes merged in v3.4-rc2. This allows to use more than one implementation of dma-mapping calls and change/select them on the struct device basis. The first client of this new infractructure is dmabounce implementation which has been completely cut out of the core, common code. The last patch of this redesign update introduces a new, experimental implementation of dma-mapping calls on top of generic IOMMU framework. This lets ARM sub-platform to transparently use IOMMU for DMA-mapping calls if one provides required IOMMU hardware. For more information please refer to the following thread: http://www.spinics.net/lists/arm-kernel/msg175729.html The last patch merges changes from both updates and provides a resolution for the conflicts which cannot be avoided when patches have been applied on the same files (mainly arch/arm/mm/dma-mapping.c)." Acked by Andrew Morton <akpm@linux-foundation.org>: "Yup, this one please. It's had much work, plenty of review and I think even Russell is happy with it." * 'for-linus' of git://git.linaro.org/people/mszyprowski/linux-dma-mapping: (28 commits) ARM: dma-mapping: use PMD size for section unmap cma: fix migration mode ARM: integrate CMA with DMA-mapping subsystem X86: integrate CMA with DMA-mapping subsystem drivers: add Contiguous Memory Allocator mm: trigger page reclaim in alloc_contig_range() to stabilise watermarks mm: extract reclaim code from __alloc_pages_direct_reclaim() mm: Serialize access to min_free_kbytes mm: page_isolation: MIGRATE_CMA isolation functions added mm: mmzone: MIGRATE_CMA migration type added mm: page_alloc: change fallbacks array handling mm: page_alloc: introduce alloc_contig_range() mm: compaction: export some of the functions mm: compaction: introduce isolate_freepages_range() mm: compaction: introduce map_pages() mm: compaction: introduce isolate_migratepages_range() mm: page_alloc: remove trailing whitespace ARM: dma-mapping: add support for IOMMU mapper ARM: dma-mapping: use alloc, mmap, free from dma_ops ARM: dma-mapping: remove redundant code and do the cleanup ... Conflicts: arch/x86/include/asm/dma-mapping.h
2012-05-25dma-buf: minor documentation fixes.Sumit Semwal
Some minor inline documentation fixes for gaps resulting from new patches. Signed-off-by: Sumit Semwal <sumit.semwal@ti.com> Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org>
2012-05-25dma-buf: add vmap interfaceDave Airlie
The main requirement I have for this interface is for scanning out using the USB gpu devices. Since these devices have to read the framebuffer on updates and linearly compress it, using kmaps is a major overhead for every update. v2: fix warn issues pointed out by Sylwester Nawrocki. v3: fix compile !CONFIG_DMA_SHARED_BUFFER and add _GPL for now Signed-off-by: Dave Airlie <airlied@redhat.com> Reviewed-by: Rob Clark <rob.clark@linaro.org> Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org>
2012-05-25dma-buf: mmap supportDaniel Vetter
Compared to Rob Clark's RFC I've ditched the prepare/finish hooks and corresponding ioctls on the dma_buf file. The major reason for that is that many people seem to be under the impression that this is also for synchronization with outstanding asynchronous processsing. I'm pretty massively opposed to this because: - It boils down reinventing a new rather general-purpose userspace synchronization interface. If we look at things like futexes, this is hard to get right. - Furthermore a lot of kernel code has to interact with this synchronization primitive. This smells a look like the dri1 hw_lock, a horror show I prefer not to reinvent. - Even more fun is that multiple different subsystems would interact here, so we have plenty of opportunities to create funny deadlock scenarios. I think synchronization is a wholesale different problem from data sharing and should be tackled as an orthogonal problem. Now we could demand that prepare/finish may only ensure cache coherency (as Rob intended), but that runs up into the next problem: We not only need mmap support to facilitate sw-only processing nodes in a pipeline (without jumping through hoops by importing the dma_buf into some sw-access only importer), which allows for a nicer ION->dma-buf upgrade path for existing Android userspace. We also need mmap support for existing importing subsystems to support existing userspace libraries. And a loot of these subsystems are expected to export coherent userspace mappings. So prepare/finish can only ever be optional and the exporter /needs/ to support coherent mappings. Given that mmap access is always somewhat fallback-y in nature I've decided to drop this optimization, instead of just making it optional. If we demonstrate a clear need for this, supported by benchmark results, we can always add it in again later as an optional extension. Other differences compared to Rob's RFC is the above mentioned support for mapping a dma-buf through facilities provided by the importer. Which results in mmap support no longer being optional. Note that this dma-buf mmap patch does _not_ support every possible insanity an existing subsystem could pull of with mmap: Because it does not allow to intercept pagefaults and shoot down ptes importing subsystems can't add some magic of their own at these points (e.g. to automatically synchronize with outstanding rendering or set up some special resources). I've done a cursory read through a few mmap implementions of various subsytems and I'm hopeful that we can avoid this (and the complexity it'd bring with it). Additonally I've extended the documentation a bit to explain the hows and whys of this mmap extension. In case we ever want to add support for explicitly cache maneged userspace mmap with a prepare/finish ioctl pair, we could specify that userspace needs to mmap a different part of the dma_buf, e.g. the range starting at dma_buf->size up to dma_buf->size*2. This works because the size of a dma_buf is invariant over it's lifetime. The exporter would obviously need to fall back to coherent mappings for both ranges if a legacy clients maps the coherent range and the architecture cannot suppor conflicting caching policies. Also, this would obviously be optional and userspace needs to be able to fall back to coherent mappings. v2: - Spelling fixes from Rob Clark. - Compile fix for !DMA_BUF from Rob Clark. - Extend commit message to explain how explicitly cache managed mmap support could be added later. - Extend the documentation with implementations notes for exporters that need to manually fake coherency. v3: - dma_buf pointer initialization goof-up noticed by Rebecca Schultz Zavin. Cc: Rob Clark <rob.clark@linaro.org> Cc: Rebecca Schultz Zavin <rebecca@android.com> Acked-by: Rob Clark <rob.clark@linaro.org> Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org>
2012-05-23Merge tag 'pm-for-3.5' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull power management updates from Rafael Wysocki: - Implementation of opportunistic suspend (autosleep) and user space interface for manipulating wakeup sources. - Hibernate updates from Bojan Smojver and Minho Ban. - Updates of the runtime PM core and generic PM domains framework related to PM QoS. - Assorted fixes. * tag 'pm-for-3.5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (25 commits) epoll: Fix user space breakage related to EPOLLWAKEUP PM / Domains: Make it possible to add devices to inactive domains PM / Hibernate: Use get_gendisk to verify partition if resume_file is integer format PM / Domains: Fix computation of maximum domain off time PM / Domains: Fix link checking when add subdomain PM / Sleep: User space wakeup sources garbage collector Kconfig option PM / Sleep: Make the limit of user space wakeup sources configurable PM / Documentation: suspend-and-cpuhotplug.txt: Fix typo PM / Domains: Cache device stop and domain power off governor results, v3 PM / Domains: Make device removal more straightforward PM / Sleep: Fix a mistake in a conditional in autosleep_store() epoll: Add a flag, EPOLLWAKEUP, to prevent suspend while epoll events are ready PM / QoS: Create device constraints objects on notifier registration PM / Runtime: Remove device fields related to suspend time, v2 PM / Domains: Rework default domain power off governor function, v2 PM / Domains: Rework default device stop governor function, v2 PM / Sleep: Add user space interface for manipulating wakeup sources, v3 PM / Sleep: Add "prevent autosleep time" statistics to wakeup sources PM / Sleep: Implement opportunistic sleep, v2 PM / Sleep: Add wakeup_source_activate and wakeup_source_deactivate tracepoints ...
2012-05-23Merge tag 'regmap-domain-deps' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap Pull a regmap kconfig dependency fix from Mark Brown: "Fix the dependency on IRQ_DOMAIN for REGMAP_IRQ in the core Fixes a missing select from the Palmas driver a bit more throoughly." * tag 'regmap-domain-deps' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap: regmap: Use select .. if to get IRQ_DOMAIN enabled
2012-05-23regmap: Use select .. if to get IRQ_DOMAIN enabledMark Brown
Ensure that we can't get randconfig breakage by doing the IRQ_DOMAIN select automatically. Don't just do the select from REGMAP_IRQ to ensure that the select actually gets noticed. Reported-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-05-22Merge branch 'sched-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler changes from Ingo Molnar: "The biggest change is the cleanup/simplification of the load-balancer: instead of the current practice of architectures twiddling scheduler internal data structures and providing the scheduler domains in colorfully inconsistent ways, we now have generic scheduler code in kernel/sched/core.c:sched_init_numa() that looks at the architecture's node_distance() parameters and (while not fully trusting it) deducts a NUMA topology from it. This inevitably changes balancing behavior - hopefully for the better. There are various smaller optimizations, cleanups and fixlets as well" * 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched: Taint kernel with TAINT_WARN after sleep-in-atomic bug sched: Remove stale power aware scheduling remnants and dysfunctional knobs sched/debug: Fix printing large integers on 32-bit platforms sched/fair: Improve the ->group_imb logic sched/nohz: Fix rq->cpu_load[] calculations sched/numa: Don't scale the imbalance sched/fair: Revert sched-domain iteration breakage sched/x86: Rewrite set_cpu_sibling_map() sched/numa: Fix the new NUMA topology bits sched/numa: Rewrite the CONFIG_NUMA sched domain support sched/fair: Propagate 'struct lb_env' usage into find_busiest_group sched/fair: Add some serialization to the sched_domain load-balance walk sched/fair: Let minimally loaded cpu balance the group sched: Change rq->nr_running to unsigned int x86/numa: Check for nonsensical topologies on real hw as well x86/numa: Hard partition cpu topology masks on node boundaries x86/numa: Allow specifying node_distance() for numa=fake x86/sched: Make mwait_usable() heed to "idle=" kernel parameters properly sched: Update documentation and comments sched_rt: Avoid unnecessary dequeue and enqueue of pushable tasks in set_cpus_allowed_rt()
2012-05-22Merge tag 'driver-core-3.5-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core updates from Greg Kroah-Hartman: "Here's the driver core, and other driver subsystems, pull request for the 3.5-rc1 merge window. Outside of a few minor driver core changes, we ended up with the following different subsystem and core changes as well, due to interdependancies on the driver core: - hyperv driver updates - drivers/memory being created and some drivers moved into it - extcon driver subsystem created out of the old Android staging switch driver code - dynamic debug updates - printk rework, and /dev/kmsg changes All of this has been tested in the linux-next releases for a few weeks with no reported problems. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>" Fix up conflicts in drivers/extcon/extcon-max8997.c where git noticed that a patch to the deleted drivers/misc/max8997-muic.c driver needs to be applied to this one. * tag 'driver-core-3.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (90 commits) uio_pdrv_genirq: get irq through platform resource if not set otherwise memory: tegra{20,30}-mc: Remove empty *_remove() printk() - isolate KERN_CONT users from ordinary complete lines sysfs: get rid of some lockdep false positives Drivers: hv: util: Properly handle version negotiations. Drivers: hv: Get rid of an unnecessary check in vmbus_prep_negotiate_resp() memory: tegra{20,30}-mc: Use dev_err_ratelimited() driver core: Add dev_*_ratelimited() family Driver Core: don't oops with unregistered driver in driver_find_device() printk() - restore prefix/timestamp printing for multi-newline strings printk: add stub for prepend_timestamp() ARM: tegra30: Make MC optional in Kconfig ARM: tegra20: Make MC optional in Kconfig ARM: tegra30: MC: Remove unnecessary BUG*() ARM: tegra20: MC: Remove unnecessary BUG*() printk: correctly align __log_buf ARM: tegra30: Add Tegra Memory Controller(MC) driver ARM: tegra20: Add Tegra Memory Controller(MC) driver printk() - restore timestamp printing at console output printk() - do not merge continuation lines of different threads ...
2012-05-22Merge branch 'for-next-arm-dma' into for-linusMarek Szyprowski
Conflicts: arch/arm/Kconfig arch/arm/mm/dma-mapping.c Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
2012-05-21drivers: add Contiguous Memory AllocatorMarek Szyprowski
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>