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* ALSA: pcm: Avoid reference to status->stateTakashi Iwai2022-09-271-8/+8
| | | | | | | | | | | | | | | | | | | | | | | In the PCM core and driver code, there are lots place referring to the current PCM state via runtime->status->state. This patch introduced a local PCM state in runtime itself and replaces those references with runtime->state. It has improvements in two aspects: - The reduction of a indirect access leads to more code optimization - It avoids a possible (unexpected) modification of the state via mmap of the status record The status->state is updated together with runtime->state, so that user-space can still read the current state via mmap like before, too. This patch touches only the ALSA core code. The changes in each driver will follow in later patches. Reviewed-by: Jaroslav Kysela <perex@perex.cz> Link: https://lore.kernel.org/r/20220926135558.26580-2-tiwai@suse.de Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: pcm: Use deferred fasync helperTakashi Iwai2022-07-291-1/+1
| | | | | | | | | | | For avoiding the potential deadlock via kill_fasync() call, use the new fasync helpers to defer the invocation from timer API. Note that it's merely a workaround. Reported-by: syzbot+8285e973a41b5aa68902@syzkaller.appspotmail.com Reported-by: syzbot+669c9abf11a6a011dd09@syzkaller.appspotmail.com Link: https://lore.kernel.org/r/20220728125945.29533-4-tiwai@suse.de Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: pcm: Fix potential AB/BA lock with buffer_mutex and mmap_lockTakashi Iwai2022-03-301-4/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | syzbot caught a potential deadlock between the PCM runtime->buffer_mutex and the mm->mmap_lock. It was brought by the recent fix to cover the racy read/write and other ioctls, and in that commit, I overlooked a (hopefully only) corner case that may take the revert lock, namely, the OSS mmap. The OSS mmap operation exceptionally allows to re-configure the parameters inside the OSS mmap syscall, where mm->mmap_mutex is already held. Meanwhile, the copy_from/to_user calls at read/write operations also take the mm->mmap_lock internally, hence it may lead to a AB/BA deadlock. A similar problem was already seen in the past and we fixed it with a refcount (in commit b248371628aa). The former fix covered only the call paths with OSS read/write and OSS ioctls, while we need to cover the concurrent access via both ALSA and OSS APIs now. This patch addresses the problem above by replacing the buffer_mutex lock in the read/write operations with a refcount similar as we've used for OSS. The new field, runtime->buffer_accessing, keeps the number of concurrent read/write operations. Unlike the former buffer_mutex protection, this protects only around the copy_from/to_user() calls; the other codes are basically protected by the PCM stream lock. The refcount can be a negative, meaning blocked by the ioctls. If a negative value is seen, the read/write aborts with -EBUSY. In the ioctl side, OTOH, they check this refcount, too, and set to a negative value for blocking unless it's already being accessed. Reported-by: syzbot+6e5c88838328e99c7e1c@syzkaller.appspotmail.com Fixes: dca947d4d26d ("ALSA: pcm: Fix races among concurrent read/write and buffer changes") Cc: <stable@vger.kernel.org> Link: https://lore.kernel.org/r/000000000000381a0d05db622a81@google.com Link: https://lore.kernel.org/r/20220330120903.4738-1-tiwai@suse.de Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: pcm: Fix races among concurrent read/write and buffer changesTakashi Iwai2022-03-221-0/+4
| | | | | | | | | | | | | | | | | | | In the current PCM design, the read/write syscalls (as well as the equivalent ioctls) are allowed before the PCM stream is running, that is, at PCM PREPARED state. Meanwhile, we also allow to re-issue hw_params and hw_free ioctl calls at the PREPARED state that may change or free the buffers, too. The problem is that there is no protection against those mix-ups. This patch applies the previously introduced runtime->buffer_mutex to the read/write operations so that the concurrent hw_params or hw_free call can no longer interfere during the operation. The mutex is unlocked before scheduling, so we don't take it too long. Cc: <stable@vger.kernel.org> Reviewed-by: Jaroslav Kysela <perex@perex.cz> Link: https://lore.kernel.org/r/20220322170720.3529-3-tiwai@suse.de Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: pcm: introduce INFO_NO_REWINDS flagPierre-Louis Bossart2021-11-241-0/+14
| | | | | | | | | | | | | | | | | | | | | When the hardware can only deal with a monotonically increasing appl_ptr, this flag can be set. In case the application requests a rewind, be it with a snd_pcm_rewind() or with a direct change of a mmap'ed pointer followed by a SNDRV_PCM_IOCTL_SYNC_PTR, this patch checks if a rewind occurred and returns an error. Credits to Takashi Iwai for identifying the path with SYNC_PTR and suggesting the pointer checks. Suggested-by: Takashi Iwai <tiwai@suse.de> Reviewed-by: Takashi Iwai <tiwai@suse.de> Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com> Reviewed-by: Kai Vehmanen <kai.vehmanen@linux.intel.com> Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> Link: https://lore.kernel.org/r/20211119230852.206310-3-pierre-louis.bossart@linux.intel.com Signed-off-by: Mark Brown <broonie@kernel.org>
* ALSA: pcm: unconditionally check if appl_ptr is in 0..boundary rangePierre-Louis Bossart2021-11-241-0/+3
| | | | | | | | | | | | | | In some cases, the appl_ptr passed by userspace is not checked before being used. This patch adds an unconditional check and returns an error code should the appl_ptr exceed the ALSA 'boundary'. Suggested-by: Takashi Iwai <tiwai@suse.de> Reviewed-by: Takashi Iwai <tiwai@suse.de> Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com> Reviewed-by: Kai Vehmanen <kai.vehmanen@linux.intel.com> Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> Link: https://lore.kernel.org/r/20211119230852.206310-2-pierre-louis.bossart@linux.intel.com Signed-off-by: Mark Brown <broonie@kernel.org>
* ALSA: memalloc: Support for non-contiguous page allocationTakashi Iwai2021-10-181-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch adds the support for allocation of non-contiguous DMA pages in the common memalloc helper. It's another SG-buffer type, but unlike the existing one, this is directional and requires the explicit sync / invalidation of dirty pages on non-coherent architectures. For this enhancement, the following points are changed: - snd_dma_device stores the DMA direction. - snd_dma_device stores need_sync flag indicating whether the explicit sync is required or not. - A new variant of helper functions, snd_dma_alloc_dir_pages() and *_all() are introduced; the old snd_dma_alloc_pages() and *_all() kept as just wrappers with DMA_BIDIRECTIONAL. - A new helper snd_dma_buffer_sync() is introduced; this gets called in the appropriate places. - A new allocation type, SNDRV_DMA_TYPE_NONCONTIG, is introduced. When the driver allocates pages with this new type, and it may require the SNDRV_PCM_INFO_EXPLICIT_SYNC flag set to the PCM hardware.info for taking the full control of PCM applptr and hwptr changes (that implies disabling the mmap of control/status data). When the buffer allocation is managed by snd_pcm_set_managed_buffer(), this flag is automatically set depending on the result of dma_need_sync() internally. Otherwise, if the buffer is managed manually, the driver has to set the flag explicitly, too. The explicit sync between CPU and device for non-coherent memory is performed at the points before and after read/write transfer as well as the applptr/hwptr syncptr ioctl. In the case of mmap mode, user-space is supposed to call the syncptr ioctl with the hwptr flag to update and fetch the status at first; this corresponds to CPU-sync. Then user-space advances the applptr via syncptr ioctl again with applptr flag, and this corresponds to the device sync with flushing. Other than the DMA direction and the explicit sync, the usage of this new buffer type is almost equivalent with the existing SNDRV_DMA_TYPE_DEV_SG; you can get the page and the address via snd_sgbuf_get_page() and snd_sgbuf_get_addr(), also calculate the continuous pages via snd_sgbuf_get_chunk_size(). For those SG-page handling, the non-contig type shares the same ops with the vmalloc handler. As we do always vmap the SG pages at first, the actual address can be deduced from the vmapped address easily without iterating the SG-list. Link: https://lore.kernel.org/r/20211017074859.24112-2-tiwai@suse.de Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: pcm: fix divide error in snd_pcm_lib_ioctlZubin Mithra2021-08-271-1/+1
| | | | | | | | | | | | | Syzkaller reported a divide error in snd_pcm_lib_ioctl. fifo_size is of type snd_pcm_uframes_t(unsigned long). If frame_size is 0x100000000, the error occurs. Fixes: a9960e6a293e ("ALSA: pcm: fix fifo_size frame calculation") Signed-off-by: Zubin Mithra <zsm@chromium.org> Reviewed-by: Guenter Roeck <groeck@chromium.org> Cc: <stable@vger.kernel.org> Link: https://lore.kernel.org/r/20210827153735.789452-1-zsm@chromium.org Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: pcm: add snd_pcm_period_elapsed() variant without acquiring lock of ↵Takashi Sakamoto2021-06-101-15/+49
| | | | | | | | | | | | | | | | | | | | | | | PCM substream Current implementation of ALSA PCM core has a kernel API, snd_pcm_period_elapsed(), for drivers to queue event to awaken processes from waiting for available frames. The function voluntarily acquires lock of PCM substream, therefore it is not called in process context for any PCM operation since the lock is already acquired. It is convenient for packet-oriented driver, at least for drivers to audio and music unit in IEEE 1394 bus. The drivers are allowed by Linux FireWire subsystem to process isochronous packets queued till recent isochronous cycle in process context in any time. This commit adds snd_pcm_period_elapsed() variant, snd_pcm_period_elapsed_without_lock(), for drivers to queue the event in the process context. Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> Link: https://lore.kernel.org/r/20210610031733.56297-2-o-takashi@sakamocchi.jp Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: pcm: use krealloc_array()Bartosz Golaszewski2020-12-151-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Use the helper that checks for overflows internally instead of manually calculating the size of the new array. Link: https://lkml.kernel.org/r/20201109110654.12547-4-brgl@bgdev.pl Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com> Reviewed-by: Takashi Iwai <tiwai@suse.de> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Borislav Petkov <bp@suse.de> Cc: Christian Knig <christian.koenig@amd.com> Cc: Christoph Lameter <cl@linux.com> Cc: Daniel Vetter <daniel@ffwll.ch> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: David Airlie <airlied@linux.ie> Cc: David Rientjes <rientjes@google.com> Cc: Gustavo Padovan <gustavo@padovan.org> Cc: James Morse <james.morse@arm.com> Cc: Jaroslav Kysela <perex@perex.cz> Cc: Jason Wang <jasowang@redhat.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Linus Walleij <linus.walleij@linaro.org> Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Cc: Mauro Carvalho Chehab <mchehab@kernel.org> Cc: Maxime Ripard <mripard@kernel.org> Cc: "Michael S . Tsirkin" <mst@redhat.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Robert Richter <rric@kernel.org> Cc: Sumit Semwal <sumit.semwal@linaro.org> Cc: Takashi Iwai <tiwai@suse.com> Cc: Thomas Zimmermann <tzimmermann@suse.de> Cc: Tony Luck <tony.luck@intel.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* ALSA: fix kernel-doc markupsMauro Carvalho Chehab2020-10-261-1/+1
| | | | | | | | | | | | | | | | Kernel-doc markups should use this format: identifier - description There is a common comment marked, instead, with kernel-doc notation. Some identifiers have different names between their prototypes and the kernel-doc markup. Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Acked-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/535182d6f55d7a7de293dda9676df68f5f60afc6.1603469755.git.mchehab+huawei@kernel.org Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: pcm: fix incorrect hw_base increaseBrent Lu2020-05-181-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There is a corner case that ALSA keeps increasing the hw_ptr but DMA already stop working/updating the position for a long time. In following log we can see the position returned from DMA driver does not move at all but the hw_ptr got increased at some point of time so snd_pcm_avail() will return a large number which seems to be a buffer underrun event from user space program point of view. The program thinks there is space in the buffer and fill more data. [ 418.510086] sound pcmC0D5p: pos 96 hw_ptr 96 appl_ptr 4096 avail 12368 [ 418.510149] sound pcmC0D5p: pos 96 hw_ptr 96 appl_ptr 6910 avail 9554 ... [ 418.681052] sound pcmC0D5p: pos 96 hw_ptr 96 appl_ptr 15102 avail 1362 [ 418.681130] sound pcmC0D5p: pos 96 hw_ptr 96 appl_ptr 16464 avail 0 [ 418.726515] sound pcmC0D5p: pos 96 hw_ptr 16464 appl_ptr 16464 avail 16368 This is because the hw_base will be increased by runtime->buffer_size frames unconditionally if the hw_ptr is not updated for over half of buffer time. As the hw_base increases, so does the hw_ptr increased by the same number. The avail value returned from snd_pcm_avail() could exceed the limit (buffer_size) easily becase the hw_ptr itself got increased by same buffer_size samples when the corner case happens. In following log, the buffer_size is 16368 samples but the avail is 21810 samples so CRAS server complains about it. [ 418.851755] sound pcmC0D5p: pos 96 hw_ptr 16464 appl_ptr 27390 avail 5442 [ 418.926491] sound pcmC0D5p: pos 96 hw_ptr 32832 appl_ptr 27390 avail 21810 cras_server[1907]: pcm_avail returned frames larger than buf_size: sof-glkda7219max: :0,5: 21810 > 16368 By updating runtime->hw_ptr_jiffies each time the HWSYNC is called, the hw_base will keep the same when buffer stall happens at long as the interval between each HWSYNC call is shorter than half of buffer time. Following is a log captured by a patched kernel. The hw_base/hw_ptr value is fixed in this corner case and user space program should be aware of the buffer stall and handle it. [ 293.525543] sound pcmC0D5p: pos 96 hw_ptr 96 appl_ptr 4096 avail 12368 [ 293.525606] sound pcmC0D5p: pos 96 hw_ptr 96 appl_ptr 6880 avail 9584 [ 293.525975] sound pcmC0D5p: pos 96 hw_ptr 96 appl_ptr 10976 avail 5488 [ 293.611178] sound pcmC0D5p: pos 96 hw_ptr 96 appl_ptr 15072 avail 1392 [ 293.696429] sound pcmC0D5p: pos 96 hw_ptr 96 appl_ptr 16464 avail 0 ... [ 381.139517] sound pcmC0D5p: pos 96 hw_ptr 96 appl_ptr 16464 avail 0 Signed-off-by: Brent Lu <brent.lu@intel.com> Reviewed-by: Jaroslav Kysela <perex@perex.cz> Cc: <stable@vger.kernel.org> Link: https://lore.kernel.org/r/1589776238-23877-1-git-send-email-brent.lu@intel.com Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: pcm: More constificationsTakashi Iwai2020-01-051-1/+1
| | | | | | | | | | Apply const prefix to more possible places: the string tables for PCM format and co, the table for the PCM type helpers, etc. Just for minor optimization and no functional changes. Link: https://lore.kernel.org/r/20200105144823.29547-6-tiwai@suse.de Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: control: Add verification for kctl accessesTakashi Iwai2020-01-041-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The current implementation of ALSA control API fully relies on the callbacks of each driver, and there is no verification of the values passed via API. This patch is an attempt to improve the situation slightly by adding the validation code for the values stored via info and get callbacks. The patch adds a new kconfig, CONFIG_SND_CTL_VALIDATION. It depends on CONFIG_SND_DEBUG and off as default since the validation would require a slight overhead including the additional call of info callback at each get callback invocation. When this config is enabled, the values stored by each info callback invocation are verified, namely: - Whether the info type is valid - Whether the number of enum items is non-zero - Whether the given info count is within the allowed boundary Similarly, the values stored at each get callback are verified as well: - Whether the values are within the given range - Whether the values are aligned with the given step - Whether any further changes are seen in the data array over the given info count The last point helps identifying a possibly invalid data type access, typically a case where the info callback declares the type being SNDRV_CTL_ELEM_TYPE_ENUMERATED while the get/put callbacks store the values in value.integer.value[] array. When a validation fails, the ALSA core logs an error message including the device and the control ID, and the API call also returns an error. So, with the new validation turned on, the driver behavior difference may be visible on user-space, too -- it's intentional, though, so that we can catch an error more clearly. The patch also introduces a new ctl access type, SNDRV_CTL_ELEM_ACCESS_SKIP_CHECK. A driver may pass this flag with other access bits to indicate that the ctl element won't be verified. It's useful when a driver code is specially written to access the data greater than info->count size by some reason. For example, this flag is actually set now in HD-audio HDMI codec driver which needs to clear the data array in the case of the disconnected monitor. Also, the PCM channel-map helper code is slightly modified to avoid the false-positive hit by this validation code, too. Link: https://lore.kernel.org/r/20200104083556.27789-1-tiwai@suse.de Signed-off-by: Takashi Iwai <tiwai@suse.de>
* Merge tag 'y2038-alsa-v8-signed' of ↵Takashi Iwai2019-12-171-14/+24
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org:/pub/scm/linux/kernel/git/arnd/playground into for-next ALSA: Fix year 2038 issue for sound subsystem This is a series I worked on with Baolin in 2017 and 2018, but we never quite managed to finish up the last pieces. During the ALSA developer meetup at ELC-E 2018 in Edinburgh, a decision was made to go with this approach for keeping best compatibility with existing source code, and then I failed to follow up by resending the patches. Now I have patches for all remaining time_t uses in the kernel, so it's absolutely time to revisit them. I have done more review of the patches myself and found a couple of minor issues that I have fixed up, otherwise the series is still the same as before. Conceptually, the idea of these patches is: - 64-bit applications should see no changes at all, neither compile-time nor run-time. - 32-bit code compiled with a 64-bit time_t currently does not work with ALSA, and requires kernel changes and/or sound/asound.h changes - Most 32-bit code using these interfaces will work correctly on a modified kernel, with or without the uapi header changes. - 32-bit code using SNDRV_TIMER_IOCTL_TREAD requires the updated header file for 64-bit time_t support - 32-bit i386 user space with 64-bit time_t is broken for SNDRV_PCM_IOCTL_STATUS, SNDRV_RAWMIDI_IOCTL_STATUS and SNDRV_PCM_IOCTL_SYNC_PTR because of i386 alignment. This is also addressed by the updated uapi header. - PCM mmap is currently supported on native x86 kernels (both 32-bit and 64-bit) but not for compat mode. This series breaks the 32-bit native mmap support for 32-bit time_t, but instead allows it for 64-bit time_t on both native and compat kernels. This seems to be the best trade-off, as mmap support is optional already, and most 32-bit code runs in compat mode anyway. - I've tried to avoid breaking compilation of 32-bit code as much as possible. Anything that does break however is likely code that is already broken on 64-bit time_t and needs source changes to fix them. [1] https://git.kernel.org/pub/scm/linux/kernel/git/arnd/playground.git y2038-alsa-v8 [2] https://lore.kernel.org/lkml/CAK8P3a2Os66+iwQYf97qh05W2JP8rmWao8zmKoHiXqVHvyYAJA@mail.gmail.com/T/#m6519cb07cfda08adf1dedea6596bb98892b4d5dc Signed-off-by: Arnd Bergmann <arnd@arndb.de> Changes since v7: (Arnd): - Fix a typo found by Ben Hutchings Changes since v6: (Arnd): - Add a patch to update the API versions - Hide a timespec reference in #ifndef __KERNEL__ to remove the last reference to time_t - Use a more readable way to do padding and describe it in the changelog - Rebase to linux-5.5-rc1, changing include/sound/soc-component.h and sound/drivers/aloop.c as needed. Changes since v5 (Arnd): - Rebased to linux-5.4-rc4 - Updated to completely remove timespec and time_t references from alsa - found and fixed a few bugs Changes since v4 (Baolin): - Add patch 5 to change trigger_tstamp member of struct snd_pcm_runtime. - Add patch 8 to change internal timespec. - Add more explanation in commit message. - Use ktime_get_real_ts64() in patch 6. - Split common code out into a separate function in patch 6. - Fix tu->tread bug in patch 6 and remove #if __BITS_PER_LONG == 64 macro. Changes since v3: - Move struct snd_pcm_status32 to pcm.h file. - Modify comments and commit message. - Add new patch2 ~ patch6. Changes since v2: - Renamed all structures to make clear. - Remove CONFIG_X86_X32 macro and introduced new compat_snd_pcm_status64_x86_32. Changes since v1: - Add one macro for struct snd_pcm_status_32 which only active in 32bits kernel. - Convert pcm_compat.c to use struct snd_pcm_status_64. - Convert pcm_native.c to use struct snd_pcm_status_64.
| * ALSA: add new 32-bit layout for snd_pcm_mmap_status/controlArnd Bergmann2019-12-131-4/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The snd_pcm_mmap_status and snd_pcm_mmap_control interfaces are one of the trickiest areas to get right when moving to 64-bit time_t in user space. The snd_pcm_mmap_status structure layout is incompatible with user space that uses a 64-bit time_t, so we need a new layout for it. Since the SNDRV_PCM_IOCTL_SYNC_PTR ioctl combines it with snd_pcm_mmap_control into snd_pcm_sync_ptr, we need to change those two as well. Both structures are also exported via an mmap() operation on certain architectures, and this suffers from incompatibility between 32-bit and 64-bit user space. As we have to change both structures anyway, this is a good opportunity to fix the mmap() problem as well, so let's standardize on the existing 64-bit layout of the structure where possible. The downside is that we lose mmap() support for existing 32-bit x86 and powerpc applications, adding that would introduce very noticeable runtime overhead and complexity. My assumption here is that not too many people will miss the removed feature, given that: - Almost all x86 and powerpc users these days are on 64-bit kernels, the majority of today's 32-bit users are on architectures that never supported mmap (ARM, MIPS, ...). - It never worked in compat mode (it was intentionally disabled there) - The application already needs to work with a fallback to SNDRV_PCM_IOCTL_SYNC_PTR, which will keep working with both the old and new structure layout. Both the ioctl() and mmap() based interfaces are changed at the same time, as they are based on the same structures. Unlike other interfaces, we change the uapi header to export both the traditional structure and a version that is portable between 32-bit and 64-bit user space code and that corresponds to the existing 64-bit layout. We further check the __USE_TIME_BITS64 macro that will be defined by future C library versions whenever we use the new time_t definition, so any existing user space source code will not see any changes until it gets rebuilt against a new C library. However, the new structures are all visible in addition to the old ones, allowing applications to explicitly request the new structures. In order to detect the difference between the old snd_pcm_mmap_status and the new __snd_pcm_mmap_status64 structure from the ioctl command number, we rely on one quirk in the structure definition: snd_pcm_mmap_status must be aligned to alignof(time_t), which leads the compiler to insert four bytes of padding in struct snd_pcm_sync_ptr after 'flags' and a corresponding change in the size of snd_pcm_sync_ptr itself. On x86-32 (and only there), the compiler doesn't use 64-bit alignment in structure, so I'm adding an explicit pad in the structure that has no effect on the existing 64-bit architectures but ensures that the layout matches for x86. The snd_pcm_uframes_t type compatibility requires another hack: we can't easily make that 64 bit wide, so I leave the type as 'unsigned long', but add padding before and after it, to ensure that the data is properly aligned to the respective 64-bit field in the in-kernel structure. For the SNDRV_PCM_MMAP_OFFSET_STATUS/CONTROL constants that are used as the virtual file offset in the mmap() function, we also have to introduce new constants that depend on hte __USE_TIME_BITS64 macro: The existing macros are renamed to SNDRV_PCM_MMAP_OFFSET_STATUS_OLD and SNDRV_PCM_MMAP_OFFSET_CONTROL_OLD, they continue to work fine on 64-bit architectures, but stop working on native 32-bit user space. The replacement _NEW constants are now used by default for user space built with __USE_TIME_BITS64, those now work on all new kernels for x86, ppc and alpha (32 and 64 bit, native and compat). It might be a good idea for a future alsa-lib to support both the _OLD and _NEW macros and use the corresponding structures directly. Unmodified alsa-lib source code will retain the current behavior, so it will no longer be able to use mmap() for the status/control structures on 32-bit systems, until either the C library gets updated to 64-bit time_t or alsa-lib gets updated to support both mmap() layouts. Co-developed-with: Baolin Wang <baolin.wang@linaro.org> Signed-off-by: Baolin Wang <baolin.wang@linaro.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
| * ALSA: Replace timespec with timespec64Baolin Wang2019-12-111-14/+22
| | | | | | | | | | | | | | | | | | | | | | | | Since timespec is not year 2038 safe on 32bit system, and we need to convert all timespec variables to timespec64 type for sound subsystem. This patch is used to do preparation for following patches, that will convert all structures defined in uapi/sound/asound.h to use 64-bit time_t. Signed-off-by: Baolin Wang <baolin.wang@linaro.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
* | ALSA: control: remove useless assignment in .info callback of PCM chmap elementTakashi Sakamoto2019-12-141-1/+0
|/ | | | | | | | | | | | | | Control elements for PCM chmap return information to userspace abount the maximum number of available PCM channels as the number of values in the element. In current implementation the number is once initialized to zero, then assigned to. This is useless and this commit fixes it. Fixes: 2d3391ec0ecc ("ALSA: PCM: channel mapping API implementation") Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> Link: https://lore.kernel.org/r/20191214131351.28950-1-o-takashi@sakamocchi.jp Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: pcm: Fix stream lock usage in snd_pcm_period_elapsed()paulhsia2019-11-131-2/+6
| | | | | | | | | | If the nullity check for `substream->runtime` is outside of the lock region, it is possible to have a null runtime in the critical section if snd_pcm_detach_substream is called right before the lock. Signed-off-by: paulhsia <paulhsia@chromium.org> Link: https://lore.kernel.org/r/20191112171715.128727-2-paulhsia@chromium.org Signed-off-by: Takashi Iwai <tiwai@suse.de>
* treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156Thomas Gleixner2019-05-301-16/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not write to the free software foundation inc 59 temple place suite 330 boston ma 02111 1307 usa extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 1334 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Richard Fontana <rfontana@redhat.com> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070033.113240726@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ALSA: pcm: Comment why read blocks when PCM is not runningRicardo Biehl Pasquali2019-02-131-0/+4
| | | | | | | | | | | | This avoids bringing back the problem introduced by 62ba568f7aef ("ALSA: pcm: Return 0 when size < start_threshold in capture") and fixed in 00a399cad1a0 ("ALSA: pcm: Revert capture stream behavior change in blocking mode"), which prevented the user from starting capture from another thread. Signed-off-by: Ricardo Biehl Pasquali <pasqualirb@gmail.com> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* Merge branch 'for-linus' into for-nextTakashi Iwai2019-02-131-16/+4
|\ | | | | | | Signed-off-by: Takashi Iwai <tiwai@suse.de>
| * ALSA: pcm: Revert capture stream behavior change in blocking modeTakashi Iwai2019-02-081-16/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In the commit 62ba568f7aef ("ALSA: pcm: Return 0 when size < start_threshold in capture"), we changed the behavior of __snd_pcm_lib_xfer() to return immediately with 0 when a capture stream has a high start_threshold. This was intended to be a correction of the behavior consistency and looked harmless, but this was the culprit of the recent breakage reported by syzkaller, which was fixed by the commit e190161f96b8 ("ALSA: pcm: Fix tight loop of OSS capture stream"). At the time for the OSS fix, I didn't touch the behavior for ALSA native API, as assuming that this behavior actually is good. But this turned out to be also broken actually for a similar deployment, e.g. one thread goes to a write loop in blocking mode while another thread controls the start/stop of the stream manually. Overall, the original commit is harmful, and it brings less merit to keep that behavior. Let's revert it. Fixes: 62ba568f7aef ("ALSA: pcm: Return 0 when size < start_threshold in capture") Fixes: e190161f96b8 ("ALSA: pcm: Fix tight loop of OSS capture stream") Cc: <stable@vger.kernel.org> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* | Merge branch 'for-linus' into for-nextTakashi Iwai2019-01-291-1/+8
|\| | | | | | | | | | | Pull 5.0 branch for further development of USB-audio quirks Signed-off-by: Takashi Iwai <tiwai@suse.de>
| * ALSA: pcm: Fix tight loop of OSS capture streamTakashi Iwai2019-01-251-1/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When the trigger=off is passed for a PCM OSS stream, it sets the start_threshold of the given substream to the boundary size, so that it won't be automatically started. This can be problematic for a capture stream, unfortunately, as detected by syzkaller. The scenario is like the following: - In __snd_pcm_lib_xfer() that is invoked from snd_pcm_oss_read() loop, we have a check whether the stream was already started or the stream can be auto-started. - The function at this check returns 0 with trigger=off since we explicitly disable the auto-start. - The loop continues and repeats calling __snd_pcm_lib_xfer() tightly, which may lead to an RCU stall. This patch fixes the bug by simply allowing the wait for non-started stream in the case of OSS capture. For native usages, it's supposed to be done by the caller side (which is user-space), hence it returns zero like before. (In theory, __snd_pcm_lib_xfer() could wait even for the native API usage cases, too; but I'd like to stay in a safer side for not breaking the existing stuff for now.) Reported-by: syzbot+fbe0496f92a0ce7b786c@syzkaller.appspotmail.com Cc: <stable@vger.kernel.org> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* | ALSA: pcm: Use the common error path in __snd_pcm_lib_xfer()Takashi Iwai2019-01-251-3/+2
|/ | | | | | | | | An open-coded error path in __snd_pcm_lib_xfer() can be replaced with the simple goto to the common error path. This also makes the error handling more consistent, i.e. when some samples have been already processed, return that size instead of the error code. Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: pcm: Update hardware pointer before start captureRicardo Biehl Pasquali2018-09-101-3/+5
| | | | | | | | | This ensures the transfer loop won't waste a run to read the few frames (if any) between start and hw_ptr update. It will wait for the next interrupt with wait_for_avail(). Signed-off-by: Ricardo Biehl Pasquali <pasqualirb@gmail.com> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: pcm: Return 0 when size < start_threshold in captureRicardo Biehl Pasquali2018-08-271-4/+9
| | | | | | | | | In __snd_pcm_lib_xfer(), when capture, if state is PREPARED and size is less than start_threshold nothing can be done. As there is no error, 0 is returned. Signed-off-by: Ricardo Biehl Pasquali <pasqualirb@gmail.com> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: pcm: Fix snd_interval_refine first/last with open min/maxTimo Wischer2018-07-111-4/+10
| | | | | | | | | | | | | | | | Without this commit the following intervals [x y), (x y) were be replaced to (y-1 y) by snd_interval_refine_last(). This was also done if y-1 is part of the previous interval. With this changes it will be replaced with [y-1 y) in case of y-1 is part of the previous interval. A similar behavior will be used for snd_interval_refine_first(). This commit adapts the changes for alsa-lib of commit 9bb985c ("pcm: snd_interval_refine_first/last: exclude value only if also excluded before") Signed-off-by: Timo Wischer <twischer@de.adit-jv.com> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: pcm: Allow drivers to set R/W wait time.Liam Girdwood2018-07-061-5/+12
| | | | | | | | | | | | Currently ALSA core blocks userspace for about 10 seconds for PCM R/W IO. This needs to be configurable for modern hardware like DSPs where no pointer update in milliseconds can indicate terminal DSP errors. Add a substream variable to set the wait time in ms. This allows userspace and drivers to recover more quickly from terminal DSP errors. Signed-off-by: Liam Girdwood <liam.r.girdwood@linux.intel.com> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: pcm: trace XRUN event at injection, tooTakashi Iwai2018-07-041-3/+4
| | | | | | | | | | | | The PCM xrun injection triggers directly snd_pcm_stop() without the standard xrun handler, hence it's not recorded on the event buffer. Ditto for snd_pcm_stop_xrun() call and SNDRV_PCM_IOCTL_XRUN ioctl. They are inconvenient from the debugging POV. Let's make them to trigger XRUN via the standard helper more consistently. Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: pcm: Clean up with snd_pcm_avail() and snd_pcm_hw_avail() helpersTakashi Iwai2018-04-171-12/+3
| | | | | | | | | | | | | Introduce two new direction-neutral helpers to calculate the avail and hw_avail values, and clean up the code with them. The two separated forward and rewind functions are gathered to the unified functions. No functional change but only code reductions. Reviewed-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: pcm: Use krealloc() for resizing the rules arrayTakashi Iwai2018-03-131-6/+2
| | | | | | | | Just a minor simplification. Change from kcalloc() shouldn't matter as each array element is fully initialized. Reviewed-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* Merge branch 'for-linus' into for-nextTakashi Iwai2018-01-151-1/+0
|\ | | | | | | | | | | | | Back-merge to the development branch for further fixes of sequencer stuff. Signed-off-by: Takashi Iwai <tiwai@suse.de>
| * ALSA: pcm: Remove yet superfluous WARN_ON()Takashi Iwai2018-01-111-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | muldiv32() contains a snd_BUG_ON() (which is morphed as WARN_ON() with debug option) for checking the case of 0 / 0. This would be helpful if this happens only as a logical error; however, since the hw refine is performed with any data set provided by user, the inconsistent values that can trigger such a condition might be passed easily. Actually, syzbot caught this by passing some zero'ed old hw_params ioctl. So, having snd_BUG_ON() there is simply superfluous and rather harmful to give unnecessary confusions. Let's get rid of it. Reported-by: syzbot+7e6ee55011deeebce15d@syzkaller.appspotmail.com Cc: <stable@vger.kernel.org> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* | Merge branch 'for-linus' into for-nextTakashi Iwai2018-01-091-2/+2
|\| | | | | | | | | | | Back-merge to continue fixing the OSS emulation code. Signed-off-by: Takashi Iwai <tiwai@suse.de>
| * ALSA: pcm: Remove incorrect snd_BUG_ON() usagesTakashi Iwai2018-01-021-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | syzkaller triggered kernel warnings through PCM OSS emulation at closing a stream: WARNING: CPU: 0 PID: 3502 at sound/core/pcm_lib.c:1635 snd_pcm_hw_param_first+0x289/0x690 sound/core/pcm_lib.c:1635 Call Trace: .... snd_pcm_hw_param_near.constprop.27+0x78d/0x9a0 sound/core/oss/pcm_oss.c:457 snd_pcm_oss_change_params+0x17d3/0x3720 sound/core/oss/pcm_oss.c:969 snd_pcm_oss_make_ready+0xaa/0x130 sound/core/oss/pcm_oss.c:1128 snd_pcm_oss_sync+0x257/0x830 sound/core/oss/pcm_oss.c:1638 snd_pcm_oss_release+0x20b/0x280 sound/core/oss/pcm_oss.c:2431 __fput+0x327/0x7e0 fs/file_table.c:210 .... This happens while it tries to open and set up the aloop device concurrently. The warning above (invoked from snd_BUG_ON() macro) is to detect the unexpected logical error where snd_pcm_hw_refine() call shouldn't fail. The theory is true for the case where the hw_params config rules are static. But for an aloop device, the hw_params rule condition does vary dynamically depending on the connected target; when another device is opened and changes the parameters, the device connected in another side is also affected, and it caused the error from snd_pcm_hw_refine(). That is, the simplest "solution" for this is to remove the incorrect assumption of static rules, and treat such an error as a normal error path. As there are a couple of other places using snd_BUG_ON() incorrectly, this patch removes these spurious snd_BUG_ON() calls. Reported-by: syzbot+6f11c7e2a1b91d466432@syzkaller.appspotmail.com Cc: <stable@vger.kernel.org> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* | ALSA: pcm: Set config update bits only when really changedTakashi Iwai2018-01-021-2/+2
|/ | | | | | | | | | | | | The PCM config space refine codes touch the parameter rmask and cmask bits when the given config parameter is changed. But in most places it checks only whether the changed value is non-zero or not, and they don't consider whether a negative error value is returned. This will lead to the incorrect update bits set upon the error path. Fix the codes to check properly the return code whether it's really updated or an error. Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: pcm: update tstamp only if audio_tstamp changedHenrik Eriksson2017-11-211-2/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 3179f6200188 ("ALSA: core: add .get_time_info") had a side effect of changing the behaviour of the PCM runtime tstamp. Prior to this change tstamp was not updated by snd_pcm_update_hw_ptr0() unless the hw_ptr had moved, after this change tstamp was always updated. For an application using alsa-lib, doing snd_pcm_readi() followed by snd_pcm_status() to estimate the age of the read samples by subtracting status->avail * [sample rate] from status->tstamp this change degraded the accuracy of the estimate on devices where the pcm hw does not provide a granular hw_ptr, e.g., devices using soc-generic-dmaengine-pcm.c and a dma-engine with residue_granularity DMA_RESIDUE_GRANULARITY_DESCRIPTOR. The accuracy of the estimate depended on the latency between the PCM hw completing a period and the driver called snd_pcm_period_elapsed() to notify ALSA core, typically determined by interrupt handling latency. After the change the accuracy of the estimate depended on the latency between the PCM hw completing a period and the application calling snd_pcm_status(), determined by the scheduling of the application process. The maximum error of the estimate is one period length in both cases, but the error average and variance is smaller when it depends on interrupt latency. Instead of always updating tstamp, update it only if audio_tstamp changed. Fixes: 3179f6200188 ("ALSA: core: add .get_time_info") Suggested-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> Signed-off-by: Henrik Eriksson <henrik.eriksson@axis.com> Cc: <stable@vger.kernel.org> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* Merge tag 'sound-4.13-rc1' of ↵Linus Torvalds2017-07-061-415/+253
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound Pull sound updates from Takashi Iwai: "This development cycle resulted in a fair amount of changes in both core and driver sides. The most significant change in ALSA core is about PCM. Also the support of of-graph card and the new DAPM widget for DSP are noteworthy changes in ASoC core. And there're lots of small changes splat over the tree, as you can see in diffstat. Below are a few highlights: ALSA core: - Removal of set_fs() hackery from PCM core stuff, and the code reorganization / optimization thereafter - Improved support of PCM ack ops, and a new ABI for improved control/status mmap handling - Lots of constifications in various codes ASoC core: - The support of of-graph card, which may work as a better generic device for a replacement of simple-card - New widget types intended mainly for use with DSPs ASoC drivers: - New drivers for Allwinner V3s SoCs - Ensonic ES8316 codec support - More Intel SKL and KBL works - More device support for Intel SST Atom (mostly for cheap tablets and 2-in-1 devices) - Support for Rockchip PDM controllers - Support for STM32 I2S and S/PDIF controllers - Support for ZTE AUD96P22 codecs HD-audio: - Support of new Realtek codecs (ALC215/ALC285/ALC289), more quirks for HP and Dell machines - A few more fixes for i915 component binding" * tag 'sound-4.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound: (418 commits) ALSA: hda - Fix unbalance of i915 module refcount ASoC: Intel: Skylake: Remove driver debugfs exit ASoC: Intel: Skylake: explicitly add the headers sst-dsp.h ALSA: hda/realtek - Remove GPIO_MASK ALSA: hda/realtek - Fix typo of pincfg for Dell quirk ALSA: pcm: add a documentation for tracepoints ALSA: atmel: ac97c: fix error return code in atmel_ac97c_probe() ALSA: x86: fix error return code in hdmi_lpe_audio_probe() ASoC: Intel: Skylake: Add support to read firmware registers ASoC: Intel: Skylake: Add sram address to sst_addr structure ASoC: Intel: Skylake: Debugfs facility to dump module config ASoC: Intel: Skylake: Add debugfs support ASoC: fix semicolon.cocci warnings ASoC: rt5645: Add quirk override by module option ASoC: rsnd: make arrays path and cmd_case static const ASoC: audio-graph-card: add widgets and routing for external amplifier support ASoC: audio-graph-card: update bindings for amplifier support ASoC: rt5665: calibration should be done before jack detection ASoC: rsnd: constify dev_pm_ops structures. ASoC: nau8825: change crosstalk-bypass property to bool type ...
| * ALSA: pcm: Fix possible inconsistent appl_ptr update via mmapTakashi Iwai2017-06-201-6/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The ALSA PCM core refers to the appl_ptr value stored on the mmapped page that is shared between kernel and user-space. Although the reference is performed in the PCM stream lock, it doesn't guarantee the atomic access when the value gets updated concurrently from the user-space on another CPU. In most of codes, this is no big problem, but still there are a few places that may result in slight inconsistencies because they access runtime->control->appl_ptr multiple times; that is, the second read might be a different value from the first value. It can be even backward or jumping, as we have no control for it. Hence, the calculation may give an unexpected value. Luckily, there is no security vulnerability by that, as far as I've checked. But still we should address it. This patch tries to reduce such possible cases. The fix is simple -- we just read once, store it to a local variable and use it for the rest calculations. The READ_ONCE() macro is used for it in order to avoid the ill-effect by possible compiler optimizations. Reviewed-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> Signed-off-by: Takashi Iwai <tiwai@suse.de>
| * Merge branch 'for-linus' into for-nextTakashi Iwai2017-06-201-2/+2
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| * | ALSA: pcm: Follow standard EXPORT_SYMBOL() declarationsTakashi Iwai2017-06-161-21/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | Just a tidy up to follow the standard EXPORT_SYMBOL*() declarations in order to improve grep-ability. - Remove superfluous blank line before EXPORT_SYMBOL*() lines Signed-off-by: Takashi Iwai <tiwai@suse.de>
| * | ALSA: pcm: remove SNDRV_PCM_IOCTL1_INFO internal commandTakashi Sakamoto2017-06-141-2/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Drivers can implement 'struct snd_pcm_ops.ioctl' to handle some requests from ALSA PCM core. These requests are internal purpose in kernel land. Usually common set of operations are used for it. SNDRV_PCM_IOCTL1_INFO is one of the requests. According to code comment, it has been obsoleted in the old days. We can see old releases in ftp.alsa-project.org. The command was firstly introduced in v0.5.0 release as SND_PCM_IOCTL1_INFO, to allow drivers to fill data of 'struct snd_pcm_channel_info' type. In v0.9.0 release, this was obsoleted by the other commands for ioctl(2) such as SNDRV_PCM_IOCTL_CHANNEL_INFO. This commit removes the long-abandoned command, bye. Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> Signed-off-by: Takashi Iwai <tiwai@suse.de>
| * | ALSA: pcm: Skip ack callback without actual appl_ptr updateTakashi Iwai2017-06-141-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We call ack callback whenever appl_ptr gets updated via pcm_lib_apply_appl_ptr(). There are various code paths to call this function. A part of them are for read/write/forward/rewind, where the appl_ptr is always changed and thus the call of ack is mandatory. OTOH, another part of code paths are from the explicit user call, e.g. via SYNC_PTR ioctl. There, we may receive the same appl_ptr value, and in such a case, calling ack is obviously superfluous. This patch adds the check of the given appl_ptr value, and returns immediately if it's no real update. Reviewed-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> Signed-off-by: Takashi Iwai <tiwai@suse.de>
| * | ALSA: pcm: add 'applptr' event of tracepointTakashi Sakamoto2017-06-121-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In design of ALSA PCM core, status and control data for runtime of ALSA PCM substream are shared between kernel/user spaces by page frame mapping with read-only attribute. Both of hardware-side and application-side position on PCM buffer are maintained as a part of the status data. In a view of ALSA PCM application, these two positions can be updated by executing ioctl(2) with some commands. There's an event of tracepoint for hardware-side position; 'hwptr'. On the other hand, no events for application-side position. This commit adds a new event for this purpose; 'applptr'. When the application-side position is changed in kernel space, this event is probed with useful information for developers. I note that the event is not probed for all of ALSA PCM applications, When applications are written by read/write programming scenario, the event is surely probed. The applications execute ioctl(2) with SNDRV_PCM_IOCTL_[READ|WRITE][N/I]_FRAMES to read/write any PCM frame, then ALSA PCM core updates the application-side position in kernel land. However, when applications are written by mmap programming scenario, if maintaining the application side position in kernel space accurately, applications should voluntarily execute ioctl(2) with SNDRV_PCM_IOCTL_SYNC_PTR to commit the number of handled PCM frames. If not voluntarily, the application-side position is not changed, thus the added event is not probed. There's a loophole, using architectures to which ALSA PCM core judges non cache coherent. In this case, the status and control data is not mapped into processe's VMA for any applications. Userland library, alsa-lib, is programmed for this case. It executes ioctl(2) with SNDRV_PCM_IOCTL_SYNC_PTR command every time to requiring the status and control data. ARM is such an architecture. Below is an example with serial sound interface (ssi) on i.mx6 quad core SoC. I use v4.1 kernel released by fsl-community with patches from VIA Tech. Inc. for VAB820, and my backport patches for relevant features for this patchset. I use Ubuntu 17.04 from ports.ubuntu.com as user land for armhf architecture. $ aplay -v -M -D hw:imx6vab820sgtl5,0 /dev/urandom -f S16_LE -r 48000 --period-size=128 --buffer-size=256 Playing raw data '/dev/urandom' : Signed 16 bit Little Endian, Rate 48000 Hz, Mono Hardware PCM card 0 'imx6-vab820-sgtl5000' device 0 subdevice 0 Its setup is: stream : PLAYBACK access : MMAP_INTERLEAVED format : S16_LE subformat : STD channels : 1 rate : 48000 exact rate : 48000 (48000/1) msbits : 16 buffer_size : 256 period_size : 128 period_time : 2666 tstamp_mode : NONE tstamp_type : MONOTONIC period_step : 1 avail_min : 128 period_event : 0 start_threshold : 256 stop_threshold : 256 silence_threshold: 0 silence_size : 0 boundary : 1073741824 appl_ptr : 0 hw_ptr : 0 mmap_area[0] = 0x76f98000,0,16 (16) $ trace-cmd record -e snd_pcm:hwptr -e snd_pcm:applptr $ trace-cmd report ... 60.208495: applptr: pcmC0D0p/sub0: prev=1792, curr=1792, avail=0, period=128, buf=256 60.208633: applptr: pcmC0D0p/sub0: prev=1792, curr=1792, avail=0, period=128, buf=256 60.210022: hwptr: pcmC0D0p/sub0: IRQ: pos=128, old=1536, base=1536, period=128, buf=256 60.210202: applptr: pcmC0D0p/sub0: prev=1792, curr=1792, avail=128, period=128, buf=256 60.210344: hwptr: pcmC0D0p/sub0: POS: pos=128, old=1664, base=1536, period=128, buf=256 60.210348: applptr: pcmC0D0p/sub0: prev=1792, curr=1792, avail=128, period=128, buf=256 60.210486: applptr: pcmC0D0p/sub0: prev=1792, curr=1792, avail=128, period=128, buf=256 60.210626: applptr: pcmC0D0p/sub0: prev=1792, curr=1920, avail=0, period=128, buf=256 60.211002: applptr: pcmC0D0p/sub0: prev=1920, curr=1920, avail=0, period=128, buf=256 60.211142: hwptr: pcmC0D0p/sub0: POS: pos=128, old=1664, base=1536, period=128, buf=256 60.211146: applptr: pcmC0D0p/sub0: prev=1920, curr=1920, avail=0, period=128, buf=256 60.211287: applptr: pcmC0D0p/sub0: prev=1920, curr=1920, avail=0, period=128, buf=256 60.212690: hwptr: pcmC0D0p/sub0: IRQ: pos=0, old=1664, base=1536, period=128, buf=256 60.212866: applptr: pcmC0D0p/sub0: prev=1920, curr=1920, avail=128, period=128, buf=256 60.212999: hwptr: pcmC0D0p/sub0: POS: pos=0, old=1792, base=1792, period=128, buf=256 60.213003: applptr: pcmC0D0p/sub0: prev=1920, curr=1920, avail=128, period=128, buf=256 60.213135: applptr: pcmC0D0p/sub0: prev=1920, curr=1920, avail=128, period=128, buf=256 60.213276: applptr: pcmC0D0p/sub0: prev=1920, curr=2048, avail=0, period=128, buf=256 60.213654: applptr: pcmC0D0p/sub0: prev=2048, curr=2048, avail=0, period=128, buf=256 60.213796: hwptr: pcmC0D0p/sub0: POS: pos=0, old=1792, base=1792, period=128, buf=256 60.213800: applptr: pcmC0D0p/sub0: prev=2048, curr=2048, avail=0, period=128, buf=256 60.213937: applptr: pcmC0D0p/sub0: prev=2048, curr=2048, avail=0, period=128, buf=256 60.215356: hwptr: pcmC0D0p/sub0: IRQ: pos=128, old=1792, base=1792, period=128, buf=256 60.215542: applptr: pcmC0D0p/sub0: prev=2048, curr=2048, avail=128, period=128, buf=256 60.215679: hwptr: pcmC0D0p/sub0: POS: pos=128, old=1920, base=1792, period=128, buf=256 60.215683: applptr: pcmC0D0p/sub0: prev=2048, curr=2048, avail=128, period=128, buf=256 60.215813: applptr: pcmC0D0p/sub0: prev=2048, curr=2048, avail=128, period=128, buf=256 60.215947: applptr: pcmC0D0p/sub0: prev=2048, curr=2176, avail=0, period=128, buf=256 ... We can surely see 'applptr' event is probed even if the application run for mmap programming scenario ('-M' option and 'hw' plugin). Below is a result of strace: 02:44:15.886382 ioctl(4, SNDRV_PCM_IOCTL_SYNC_PTR, 0x56a32b30) = 0 02:44:15.887203 poll([{fd=4, events=POLLOUT|POLLERR|POLLNVAL}], 1, -1) = 1 ([{fd=4, revents=POLLOUT}]) 02:44:15.887471 ioctl(4, SNDRV_PCM_IOCTL_SYNC_PTR, 0x56a32b30) = 0 02:44:15.887637 ioctl(4, SNDRV_PCM_IOCTL_SYNC_PTR, 0x56a32b30) = 0 02:44:15.887805 ioctl(4, SNDRV_PCM_IOCTL_SYNC_PTR, 0x56a32b30) = 0 02:44:15.887969 ioctl(4, SNDRV_PCM_IOCTL_SYNC_PTR, 0x56a32b30) = 0 02:44:15.888132 read(3, "..."..., 256) = 256 02:44:15.889040 ioctl(4, SNDRV_PCM_IOCTL_SYNC_PTR, 0x56a32b30) = 0 02:44:15.889221 ioctl(4, SNDRV_PCM_IOCTL_SYNC_PTR, 0x56a32b30) = 0 02:44:15.889431 ioctl(4, SNDRV_PCM_IOCTL_SYNC_PTR, 0x56a32b30) = 0 02:44:15.889606 poll([{fd=4, events=POLLOUT|POLLERR|POLLNVAL}], 1, -1) = 1 ([{fd=4, revents=POLLOUT}]) 02:44:15.889833 ioctl(4, SNDRV_PCM_IOCTL_SYNC_PTR, 0x56a32b30) = 0 02:44:15.889998 ioctl(4, SNDRV_PCM_IOCTL_SYNC_PTR, 0x56a32b30) = 0 02:44:15.890164 ioctl(4, SNDRV_PCM_IOCTL_SYNC_PTR, 0x56a32b30) = 0 02:44:15.891048 ioctl(4, SNDRV_PCM_IOCTL_SYNC_PTR, 0x56a32b30) = 0 02:44:15.891228 read(3, "..."..., 256) = 256 02:44:15.891497 ioctl(4, SNDRV_PCM_IOCTL_SYNC_PTR, 0x56a32b30) = 0 02:44:15.891661 ioctl(4, SNDRV_PCM_IOCTL_SYNC_PTR, 0x56a32b30) = 0 02:44:15.891829 ioctl(4, SNDRV_PCM_IOCTL_SYNC_PTR, 0x56a32b30) = 0 02:44:15.891991 poll([{fd=4, events=POLLOUT|POLLERR|POLLNVAL}], 1, -1) = 1 ([{fd=4, revents=POLLOUT}]) 02:44:15.893007 ioctl(4, SNDRV_PCM_IOCTL_SYNC_PTR, 0x56a32b30) = 0 We can see 7 calls of ioctl(2) with SNDRV_PCM_IOCTL_SYNC_PTR per loop with call of poll(2). 128 PCM frames are transferred per loop of one poll(2), because the PCM substream is configured with S16_LE format and 1 channel (2 byte * 1 * 128 = 256 bytes). This equals to the size of period of PCM buffer. Comparing to the probed data, one of the 7 calls of ioctl(2) is actually used to commit the number of copied PCM frames to kernel space. The other calls are just used to check runtime status of PCM substream; e.g. XRUN. The tracepoint event is useful to investigate this case. I note that below modules are related to the above sample. * snd-soc-dummy.ko * snd-soc-imx-sgtl5000.ko * snd-soc-fsl-ssi.ko * snd-soc-imx-pcm-dma.ko * snd-soc-sgtl5000.ko My additional note is lock acquisition. The event is probed under acquiring PCM stream lock. This means that calculation in the event is free from any hardware events. Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> Signed-off-by: Takashi Iwai <tiwai@suse.de>
| * | ALSA: pcm: unify codes to operate application-side position on PCM bufferTakashi Sakamoto2017-06-121-3/+24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In a series of recent work, ALSA PCM core got some arrangements to handle application-side position on PCM buffer. However, relevant codes still disperse to two translation units This commit unifies these codes into a helper function. Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> Signed-off-by: Takashi Iwai <tiwai@suse.de>
| * | ALSA: pcm: localize snd_pcm_hw_params_choose()Takashi Sakamoto2017-06-091-40/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As of v4.12, snd_pcm_hw_params_choose() is just called in a process context of ioctl(2) with SNDRV_PCM_IOCTL_HW_PARAMS. The function locates in a different file, which has no tracepoints. This commit moves the function to a file with the tracepoints for later commit. Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> Signed-off-by: Takashi Iwai <tiwai@suse.de>
| * | ALSA: pcm: Direct in-kernel read/write supportTakashi Iwai2017-06-021-1/+25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Now all materials are ready, let's allow the direct in-kernel read/write, i.e. a kernel-space buffer is passed for read or write, instead of the normal user-space buffer. This feature is used by OSS layer and UAC1 driver, for example. The __snd_pcm_lib_xfer() takes in_kernel argument that indicates the in-kernel buffer copy. When this flag is set, another transfer code is used. It's either via copy_kernel PCM ops or the normal memcpy(), depending on the driver setup. As external API, snd_pcm_kernel_read(), *_write() and other variants are provided. That's all. This support is really simple because of the code refactoring until now. Reviewed-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> Signed-off-by: Takashi Iwai <tiwai@suse.de>
| * | ALSA: pcm: Simplify snd_pcm_playback_silence()Takashi Iwai2017-06-021-30/+20
| | | | | | | | | | | | | | | | | | | | | Use the existing silence helper codes for simplification. Reviewed-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> Signed-off-by: Takashi Iwai <tiwai@suse.de>
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