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2018-12-19stm class: Fix a module refcount leak in policy creation error pathAlexander Shishkin1-5/+7
Commit c7fd62bc69d0 ("stm class: Introduce framing protocol drivers") adds a bug into the error path of policy creation, that would do a module_put() on a wrong module, if one tried to create a policy for an stm device which already has a policy, using a different protocol. IOW, | mkdir /config/stp-policy/dummy_stm.0:p_basic.test | mkdir /config/stp-policy/dummy_stm.0:p_sys-t.test # puts "p_basic" | mkdir /config/stp-policy/dummy_stm.0:p_sys-t.test # "p_basic" -> -1 throws: | general protection fault: 0000 [#1] SMP PTI | CPU: 3 PID: 2887 Comm: mkdir | RIP: 0010:module_put.part.31+0xe/0x90 | Call Trace: | module_put+0x13/0x20 | stm_put_protocol+0x11/0x20 [stm_core] | stp_policy_make+0xf1/0x210 [stm_core] | ? __kmalloc+0x183/0x220 | ? configfs_mkdir+0x10d/0x4c0 | configfs_mkdir+0x169/0x4c0 | vfs_mkdir+0x108/0x1c0 | do_mkdirat+0xe8/0x110 | __x64_sys_mkdir+0x1b/0x20 | do_syscall_64+0x5a/0x140 | entry_SYSCALL_64_after_hwframe+0x44/0xa9 Correct this sad mistake by calling calling 'put' on the correct reference, which happens to match another error path in the same function, so we consolidate the two at the same time. Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Fixes: c7fd62bc69d0 ("stm class: Introduce framing protocol drivers") Reported-by: Ammy Yi <ammy.yi@intel.com> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-11stm class: Use memcat_p()Alexander Shishkin1-28/+1
Instead of a local copy, use the memcat_p() helper to merge policy node attributes. Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Tested-by: Mathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-11stm class: heartbeat: Fix whitespaceAlexander Shishkin1-1/+1
Fix whitespace in the code for better readability, no functional changes. Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Tested-by: Mathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-11stm class: p_sys-t: Add support for CLOCKSYNC packetsAlexander Shishkin1-0/+80
This adds support for CLOCKSYNC SyS-T packets, that establish correlation between the transport clock (STP timestamps) and SyS-T timestamps. These packets are sent periodically to allow the decoder to keep both time sources in sync. Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Tested-by: Mathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-11stm class: Add MIPI SyS-T protocol supportAlexander Shishkin3-0/+318
This adds support for MIPI SyS-T protocol as specified in an open standard [1]. In addition to marking message boundaries, it also supports tagging messages with the source UUID, to provide better distinction between trace sources, including payload length and timestamp in the message's metadata. This driver adds attributes to STP policy nodes to control/configure these metadata features. [1] https://www.mipi.org/specifications/sys-t Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Tested-by: Mathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-11stm class: Switch over to the protocol driverAlexander Shishkin2-16/+21
Now that the default framing protocol is factored out into its own driver, switch over to using the driver for writing data. To that end, make the policy code require a valid protocol name (or absence thereof, which is equivalent to "p_basic"). Also, to make transition easier, make stm class request "p_basic" module at initialization time. Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Tested-by: Mathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-11stm class: Factor out default framing protocolAlexander Shishkin3-0/+67
The STP framing pattern that the stm class implicitly applies to the data payload is, in fact, a protocol. This patch moves the relevant code out of the stm core into its own driver module. Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Tested-by: Mathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-11stm class: Add a helper for writing data packetsAlexander Shishkin2-13/+41
Add a helper to write a sequence of bytes as STP data packets. This is used by protocol drivers to output their metadata, as well as the actual data payload. Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Tested-by: Mathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-11stm class: Introduce framing protocol driversAlexander Shishkin3-18/+318
At the moment, the stm class applies a certain STP framing pattern to the data as it is written to the underlying STM device. In order to allow different framing patterns (aka protocols), this patch introduces the concept of STP protocol drivers, defines data structures and APIs for the protocol drivers to use. Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Tested-by: Mathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-11stm class: Clean up stp_configfs_initAlexander Shishkin1-5/+1
Minor code shortening, no functional changes. Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Tested-by: Mathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-11stm class: Clarify configfs root type/operations namesAlexander Shishkin1-6/+6
The current naming of stp-policy root type and group ops is confusing, rename them for better readability. Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Tested-by: Mathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-11stm class: Rework policy node fallbackAlexander Shishkin3-44/+55
Currently, if no matching policy node can be found for a trace source, we'll try to use "default" policy node, then, if that doesn't exist, we'll pick the first node, in order of creation. If that also fails, we'll allocate M/C range from the beginning of the device's M/C range. This makes it difficult to know which node (if any) was used in any particular case. In order to make things more deterministic, the new order is as follows: * if they supply ID string, use that and nothing else, * if they are a task, use their task name (comm), * use "default", if it exists, * return failure, to let them know there is no suitable rule. This should provide enough convenience with the "default" catch-all node, while not leaving *everything* to chance. As a side effect, this relaxes the requirement of using ioctl() for identification with the possibility of using task names as policy nodes. Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Tested-by: Mathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-06-05Merge tag 'char-misc-4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-miscLinus Torvalds1-9/+1
Pull char/misc driver updates from Greg KH: "Here is the "big" char and misc driver patches for 4.18-rc1. It's not a lot of stuff here, but there are some highlights: - coreboot driver updates - soundwire driver updates - android binder updates - fpga big sync, mostly documentation - lots of minor driver updates All of these have been in linux-next for a while with no reported issues" * tag 'char-misc-4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (81 commits) vmw_balloon: fixing double free when batching mode is off MAINTAINERS: Add driver-api/fpga path fpga: clarify that unregister functions also free documentation: fpga: move fpga-region.txt to driver-api documentation: fpga: add bridge document to driver-api documentation: fpga: move fpga-mgr.txt to driver-api Documentation: fpga: move fpga overview to driver-api fpga: region: kernel-doc fixes fpga: bridge: kernel-doc fixes fpga: mgr: kernel-doc fixes fpga: use SPDX fpga: region: change api, add fpga_region_create/free fpga: bridge: change api, don't use drvdata fpga: manager: change api, don't use drvdata fpga: region: don't use drvdata in common fpga code Drivers: hv: vmbus: Removed an unnecessary cast from void * ver_linux: Drop redundant calls to system() to test if file is readable ver_linux: Move stderr redirection from function parameter to function body misc: IBM Virtual Management Channel Driver (VMC) rpmsg: Correct support for MODULE_DEVICE_TABLE() ...
2018-05-26hwtracing: stm: fix build error on some archesGreg Kroah-Hartman1-0/+1
Commit b5e2ced9bf81 ("stm class: Use vmalloc for the master map") caused a build error on some arches as vmalloc.h was not explicitly included. Fix that by adding it to the list of includes. Fixes: b5e2ced9bf81 ("stm class: Use vmalloc for the master map") Reported-by: kbuild test robot <lkp@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-25stm class: Use vmalloc for the master mapAlexander Shishkin1-3/+3
Fengguang is running into a warning from the buddy allocator: > swapper/0: page allocation failure: order:9, mode:0x14040c0(GFP_KERNEL|__GFP_COMP), nodemask=(null) > CPU: 1 PID: 1 Comm: swapper/0 Not tainted 4.17.0-rc1 #262 > Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014 > Call Trace: ... > __kmalloc+0x14b/0x180: ____cache_alloc at mm/slab.c:3127 > stm_register_device+0xf3/0x5c0: stm_register_device at drivers/hwtracing/stm/core.c:695 ... Which is basically a result of the stm class trying to allocate ~512kB for the dummy_stm with its default parameters. There's no reason, however, for it not to be vmalloc()ed instead, which is what this patch does. Reported-by: Fengguang Wu <fengguang.wu@intel.com> Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> CC: stable@vger.kernel.org # v4.4+ Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-14coresight: Moving framework and drivers to SPDX identifierMathieu Poirier1-9/+1
Moving all kernel side CoreSight framework and drivers to SPDX identifier. Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-28stm class: Make dummy's master/channel ranges configurableAlexander Shishkin1-3/+21
To allow for more flexible testing of the stm class, make it possible to specify the ranges of masters and channels that the dummy_stm devices cover. This is done via module parameters. Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
2018-03-28stm class: Add SPDX GPL-2.0 header to replace GPLv2 boilerplateAlexander Shishkin6-54/+6
This adds SPDX GPL-2.0 header to to stm core files and removes the GPLv2 boilerplate text. Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
2017-12-04tracing: Pass export pointer as argument to ->write()Felipe Balbi1-2/+4
By passing an export descriptor to the write function, users don't need to keep a global static pointer and can rely on container_of() to fetch their own structure. Link: http://lkml.kernel.org/r/20170602102025.5140-1-felipe.balbi@linux.intel.com Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Reviewed-by: Chunyan Zhang <zhang.chunyan@linaro.org> Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-11-14Merge tag 'configfs-for-4.15' of git://git.infradead.org/users/hch/configfsLinus Torvalds1-5/+5
Pull configfs updates from Christoph Hellwig: "A couple of configfs cleanups: - proper use of the bool type (Thomas Meyer) - constification of struct config_item_type (Bhumika Goyal)" * tag 'configfs-for-4.15' of git://git.infradead.org/users/hch/configfs: RDMA/cma: make config_item_type const stm class: make config_item_type const ACPI: configfs: make config_item_type const nvmet: make config_item_type const usb: gadget: configfs: make config_item_type const PCI: endpoint: make config_item_type const iio: make function argument and some structures const usb: gadget: make config_item_type structures const dlm: make config_item_type const netconsole: make config_item_type const nullb: make config_item_type const ocfs2/cluster: make config_item_type const target: make config_item_type const configfs: make ci_type field, some pointers and function arguments const configfs: make config_item_type const configfs: Fix bool initialization/comparison
2017-11-02License cleanup: add SPDX GPL-2.0 license identifier to files with no licenseGreg Kroah-Hartman1-0/+1
Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-10-19stm class: make config_item_type constBhumika Goyal1-5/+5
Make config_item_type structures const as they are either passed to a function having the argument as const or used inside a if statement or stored in the const "ci_type" field of a config_item structure. Done using Coccinelle. Signed-off-by: Bhumika Goyal <bhumirks@gmail.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-09-22stm class: Fix a use-after-freeAlexander Shishkin1-1/+1
For reasons unknown, the stm_source removal path uses device_destroy() to kill the underlying device object. Because device_destroy() uses devt to look for the device to destroy and the fact that stm_source devices don't have one (or all have the same one), it just picks the first device in the class, which may well be the wrong one. That is, loading stm_console and stm_heartbeat and then removing both will die in dereferencing a freed object. Since this should have been device_unregister() in the first place, use it instead of device_destroy(). Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Fixes: 7bd1d4093c2 ("stm class: Introduce an abstraction for System Trace Module devices") Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-25stm: Potential read overflow in stm_char_policy_set_ioctl()Dan Carpenter1-1/+1
The "size" variable comes from the user so we need to verify that it's large enough to hold an stp_policy_id struct. Fixes: 7bd1d4093c2f ("stm class: Introduce an abstraction for System Trace Module devices") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
2016-12-15Merge tag 'trace-v4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-traceLinus Torvalds5-4/+105
Pull tracing updates from Steven Rostedt: "This release has a few updates: - STM can hook into the function tracer - Function filtering now supports more advance glob matching - Ftrace selftests updates and added tests - Softirq tag in traces now show only softirqs - ARM nop added to non traced locations at compile time - New trace_marker_raw file that allows for binary input - Optimizations to the ring buffer - Removal of kmap in trace_marker - Wakeup and irqsoff tracers now adhere to the set_graph_notrace file - Other various fixes and clean ups" * tag 'trace-v4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (42 commits) selftests: ftrace: Shift down default message verbosity kprobes/trace: Fix kprobe selftest for newer gcc tracing/kprobes: Add a helper method to return number of probe hits tracing/rb: Init the CPU mask on allocation tracing: Use SOFTIRQ_OFFSET for softirq dectection for more accurate results tracing/fgraph: Have wakeup and irqsoff tracers ignore graph functions too fgraph: Handle a case where a tracer ignores set_graph_notrace tracing: Replace kmap with copy_from_user() in trace_marker writing ftrace/x86_32: Set ftrace_stub to weak to prevent gcc from using short jumps to it tracing: Allow benchmark to be enabled at early_initcall() tracing: Have system enable return error if one of the events fail tracing: Do not start benchmark on boot up tracing: Have the reg function allow to fail ring-buffer: Force rb_end_commit() and rb_set_commit_to_write() inline ring-buffer: Froce rb_update_write_stamp() to be inlined ring-buffer: Force inline of hotpath helper functions tracing: Make __buffer_unlock_commit() always_inline tracing: Make tracepoint_printk a static_key ring-buffer: Always inline rb_event_data() ring-buffer: Make rb_reserve_next_event() always inlined ...
2016-11-22stm: Mark the functions of writing STM with notraceChunyan Zhang1-3/+4
If CONFIG_STM_SOURCE_FTRACE is selected, Function trace data can be writen to sink via STM, all functions that related to writing data packets to STM should be marked 'notrace' to avoid being traced by Ftrace, otherwise the program would stall into an endless loop. Link: http://lkml.kernel.org/r/1479715043-6534-7-git-send-email-zhang.chunyan@linaro.org Signed-off-by: Chunyan Zhang <zhang.chunyan@linaro.org> Acked-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-11-22stm dummy: Mark dummy_stm_packet() with notraceChunyan Zhang1-1/+1
If CONFIG_STM_SOURCE_FTRACE is selected, Function trace data can be writen to sink via STM, all functions that related to writing data packets to STM should be marked 'notrace' to avoid being traced by Ftrace, otherwise the program would stall into an endless loop. Link: http://lkml.kernel.org/r/1479715043-6534-6-git-send-email-zhang.chunyan@linaro.org Signed-off-by: Chunyan Zhang <zhang.chunyan@linaro.org> Acked-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-11-22stm class: ftrace: Add ftrace-export-over-stm driverChunyan Zhang3-0/+100
This patch adds a driver that models itself as an stm_source called stm_ftrace. Once the stm device and stm_ftrace have been linked via sysfs, the driver registers itself as a trace_export and everything passed to the interface from Ftrace subsystem will end up in the STM trace engine. Link: http://lkml.kernel.org/r/1479715043-6534-3-git-send-email-zhang.chunyan@linaro.org Signed-off-by: Chunyan Zhang <zhang.chunyan@linaro.org> Acked-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-11-18stm class: Fix device leak in open error pathJohan Hovold1-3/+5
Make sure to drop the reference taken by class_find_device() also on allocation errors in open(). Signed-off-by: Johan Hovold <johan@kernel.org> Fixes: 7bd1d4093c2f ("stm class: Introduce an abstraction for...") Cc: stable@vger.kernel.org # v4.6+ Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
2016-07-01stm class: Add runtime power management handlingAlexander Shishkin1-0/+52
Currently, there's no runtime pm in stm class devices, which makes it harder for the underlying hardware drivers to handle their power management. This patch applies the following runtime pm policy to stm class devices, which their parents can rely on for their power management tracking: * device is in use during character device writes, * delayed autosuspend is used to keep it active between adjacent writes, * device is in use while mmio regions are mapped, * device is is use while any stm_source devices are linked to it. Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org> Cc: Chunyan Zhang <zhang.chunyan@linaro.org>
2016-05-03stm class: Support devices that override software assigned mastersAlexander Shishkin1-0/+15
Some STM devices adjust software assigned master numbers depending on the trace source and its runtime state and whatnot. This patch adds a sysfs attribute to inform the trace-side software that master numbers assigned to software sources will not match those in the STP stream, so that, for example, master/channel allocation policy can be adjusted accordingly. Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-08stm class: Remove unnecessary pointer incrementAlexander Shishkin1-1/+1
Readability: a postfix increment is used on a pointer which is not used anywhere afterwards, which may send the reader looking through the function one extra time. Drop the unnecessary increment. Reported-by: Alan Cox <alan.cox@intel.com> Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Reviewed-by: Laurent Fert <laurent.fert@intel.com>
2016-04-08stm class: Fix stm device initialization orderAlexander Shishkin1-8/+9
Currently, stm_register_device() makes the device visible and then proceeds to initializing spinlocks and other properties, which leaves a window when the device can already be opened but is not yet fully operational. Fix this by reversing the initialization order. Reported-by: Alan Cox <alan.cox@intel.com> Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Reviewed-by: Laurent Fert <laurent.fert@intel.com>
2016-04-08stm class: Do not leak the chrdev in error pathAlexander Shishkin1-0/+2
Currently, the error path of stm_register_device() forgets to unregister the chrdev. Fix this. Reported-by: Alan Cox <alan.cox@intel.com> Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Reviewed-by: Laurent Fert <laurent.fert@intel.com>
2016-04-08stm class: Remove a pointless lineAlexander Shishkin1-2/+0
No point in explicitly setting something to zero right after we explicitly checked that it is zero. Fix this. Reported-by: Alan Cox <alan.cox@intel.com> Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Reviewed-by: Laurent Fert <laurent.fert@intel.com>
2016-04-08stm class: stm_heartbeat: Make nr_devs parameter read-onlyAlexander Shishkin1-9/+5
Changing nr_devs after the module has been loaded doesn't actually change anything, so just make it read-only. Reported-by: Alan Cox <alan.cox@intel.com> Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Reviewed-by: Laurent Fert <laurent.fert@intel.com>
2016-04-08stm class: dummy_stm: Make nr_dummies parameter read-onlyAlexander Shishkin1-9/+5
Changing nr_dummies after the module has been loaded doesn't actually change anything, so just make it read-only. Reported-by: Alan Cox <alan.cox@intel.com> Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Reviewed-by: Laurent Fert <laurent.fert@intel.com>
2016-04-08stm class: Fix integer boundary checks for master rangeChunyan Zhang1-2/+1
Master IDs are of unsigned int type, yet in the configfs policy code we're validating user's input against INT_MAX. This is both pointless and misleading as the real limits are imposed by the stm device's [sw_start..sw_end] (which are also limited by the spec to be no larger than 2^16-1). Clean this up by getting rid of the redundant comparisons. Signed-off-by: Chunyan Zhang <zhang.chunyan@linaro.org> Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Reviewed-by: Laurent Fert <laurent.fert@intel.com>
2016-02-20stm class: dummy_stm: Add link callback for fault injectionAlexander Shishkin1-0/+14
STM device's link callback has the power to abort master/channel assignment by returning a negative error code. Use this in dummy stm device to optionally abort assigning certain channel IDs. This is useful as fault injection into the stm class core, for testing purposes. Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-20stm class: Plug stm device's unlink callbackAlexander Shishkin1-4/+19
STM device's unlink callback is never actually called from anywhere in the stm class code. This patch adds calls to stm driver's unlink method after the unlinking has succeeded. Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-20stm class: Fix a race in unlinkingAlexander Shishkin1-12/+42
There is a window in stm_source_link_drop(), during which the source's link may change before locks are acquired. When this happens, it throws a warning, since this is not an expected scenario. This patch handles the race in such a way that if the link appears to have changed by the time we took the locks, it will release them and repeat the whole unlinking procedure from the beginning, unless the other contender beat us to it. Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-20stm class: Fix unbalanced module/device refcountingAlexander Shishkin1-6/+14
STM code takes references to the stm device and its module for the duration of the character device's existence or the stm_source link. Dropping these references is not well balanced everywhere, which may lead to leaks. This patch balances the acquisition and releasing of these two references and annotates each site so that it's easier to verify correctness by reading the code. Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-20stm class: Guard output assignment against concurrencyAlexander Shishkin2-0/+18
It is possible to concurrently assign the same output (a character device writer or an stm_source device) to different stm devices, which sets off a strategically placed warning in stm_output_assign(). To avoid this, use a spinlock to serialize (un)assignments between outputs and stm devices. Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-20stm class: Fix unlocking braino in the error pathAlexander Shishkin1-4/+3
If an illegal attempt is made to unlink stm source device from an stm device, the stm device's link spinlock mistakenly remains locked. While this really shouldn't happen (there's a warning in place), the locking should remain in order so that we can still recover from this situation if it indeed does happen. This patch unifies the unlocking in the exit path of __stm_source_link_drop() to fix this. Reported-by: Laurent Fert <laurent.fert@intel.com> Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-20stm class: Add heartbeat stm source deviceAlexander Shishkin3-0/+143
Heartbeat stm source may have multiple instances (for connecting to different stm devices). Each instance will send a periodic test message over its stm device when it is linked. This can be used for testing stm class framework, stm device drivers or as a heartbeat over the stm link. Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-20stm class: dummy_stm: Create multiple devicesAlexander Shishkin1-9/+48
STM framework should be able to handle multiple STM devices at a time, each one with its own master allocation policy. This patch changes dummy_stm driver to create multiple STM sinks to help testing the framework. Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-20stm class: Support devices with multiple instancesAlexander Shishkin1-3/+4
By convention, the name of the stm policy directory in configfs consists of the device name to which it applies and the actual policy name, separated by a dot. Now, some devices already have dots in their names that separate name of the actual device from its instance identifier. Such devices will result in two (or more, who can tell) dots in the policy directory name. Existing policy code, however, will treat the first dot as the one that separates device name from policy name, therefore failing the above case. This patch makes the last dot in the directory name be the separator, thus prohibiting dots from being used in policy names. Suggested-by: Chunyan Zhang <zhang.chunyan@linaro.org> Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-20stm class: Use driver's packet callback return valueAlexander Shishkin1-7/+12
STM drivers provide a callback to generate/send individual STP packets; it also tells the stm core how many bytes of payload it has consumed. However, we would also need to use the negative space of this return value to communicate errors that occur during the packet generation, in which case the stm core will have to take appropriate action. For now, we need to account for the possibility that the stm driver may not support certain combinations of packet type/flags, in which case it is expected to signal an error. Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-20stm class: Fix master deallocation in device unregisteringChunyan Zhang1-1/+1
The device unregister path uses wrong master index range when it tries to free the allocated masters, it should, as does the rest of the stm class code, use real master IDs. This patch fixes the device unregister path to use real master IDs to avoid memory leaks after unloading the stm driver. Signed-off-by: Chunyan Zhang <zhang.chunyan@linaro.org> [alexander.shishkin@intel.com: re-wrote the commit message] Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-20stm class: Use a signed return type for stm_find_master_chanLucas Tanure1-2/+2
The return type "unsigned int" was used by the stm_find_master_chan function despite of the aspect that it will eventually return a negative error code. Done with the help of Coccinelle. Signed-off-by: Lucas Tanure <tanure@linux.com> Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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