As the last-standing user of PCM vmalloc buffer helper API took its
own buffer management, we can finally drop those API functions, which
were leftover after reorganization of ALSA memalloc code.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: https://patch.msgid.link/20240807152725.18948-3-tiwai@suse.de
We can simplify the code gracefully with new guard() macro and co for
automatic cleanup of locks.
Only the code refactoring, and no functional changes.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: https://lore.kernel.org/r/20240227085306.9764-22-tiwai@suse.de
The PCM memory allocation helpers have a sanity check against too many
buffer allocations. However, the check is performed without a proper
lock and the allocation isn't serialized; this allows user to allocate
more memories than predefined max size.
Practically seen, this isn't really a big problem, as it's more or
less some "soft limit" as a sanity check, and it's not possible to
allocate unlimitedly. But it's still better to address this for more
consistent behavior.
The patch covers the size check in do_alloc_pages() with the
card->memory_mutex, and increases the allocated size there for
preventing the further overflow. When the actual allocation fails,
the size is decreased accordingly.
Reported-by: BassCheck <bass@buaa.edu.cn>
Reported-by: Tuo Li <islituo@gmail.com>
Link: https://lore.kernel.org/r/CADm8Tek6t0WedK+3Y6rbE5YEt19tML8BUL45N2ji4ZAz1KcN_A@mail.gmail.com
Reviewed-by: Jaroslav Kysela <perex@perex.cz>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20230703112430.30634-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Each kernel doc comment expects the definition of the return value in
a proper format. This patch adds or fixes the missing entries for PCM
API.
Link: https://lore.kernel.org/r/20220713104759.4365-3-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Pointer substream is being dereferenced on the assignment of pointer card
before substream is being null checked with the macro PCM_RUNTIME_CHECK.
Although PCM_RUNTIME_CHECK calls BUG_ON, it still is useful to perform the
the pointer check before card is assigned.
Fixes: d4cfb30fce ("ALSA: pcm: Set per-card upper limit of PCM buffer allocations")
Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Link: https://lore.kernel.org/r/20220424205945.1372247-1-colin.i.king@gmail.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
We have no protection against concurrent PCM buffer preallocation
changes via proc files, and it may potentially lead to UAF or some
weird problem. This patch applies the PCM open_mutex to the proc
write operation for avoiding the racy proc writes and the PCM stream
open (and further operations).
Cc: <stable@vger.kernel.org>
Reviewed-by: Jaroslav Kysela <perex@perex.cz>
Link: https://lore.kernel.org/r/20220322170720.3529-5-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
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>
A few drivers want to have rather the exact buffer preallocation at
the driver probe time and keep using it for the whole operations
without allowing dynamic buffer allocation. For satisfying the
demands, this patch extends the managed buffer allocation API
slightly.
Namely, when 0 is passed to max argument of the allocation helper
functions snd_pcm_set_managed_buffer*(), it treats as if the fixed
size allocation of the given size. If the pre-allocation fails in
this mode, the function returns now -ENOMEM. Otherwise, i.e. max
argument is non-zero, the function never returns -ENOMEM but tries to
fall back to the smaller chunks and allows the dynamic allocation
later -- which is still the default behavior until now.
For more intuitive use, also two new helpers are added for handling
the fixed size buffer allocation, too: snd_pcm_set_fixed_buffer() and
snd_pcm_set_fixed_buffer_all().
Acked-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20210802072815.13551-4-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
This patch introduces the ops table to each memory allocation type
(SNDRV_DMA_TYPE_XXX) and abstract the handling for the better code
management. Then we get separate the page allocation, release and
other tasks for each type, especially for the SG buffer.
Each buffer type has now callbacks in the struct snd_malloc_ops, and
the common helper functions call those ops accordingly. The former
inline code that is specific to SG-buffer is moved into the local
sgbuf.c, and we can simplify the PCM code without details of memory
handling.
Link: https://lore.kernel.org/r/20210609162551.7842-4-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Building with 'make W=1' shows some warnings about empty function-style
macros:
sound/core/pcm_memory.c: In function 'preallocate_pages':
sound/core/pcm_memory.c:236:49: error: suggest braces around empty body in an 'if' statement [-Werror=empty-body]
236 | preallocate_info_init(substream);
sound/core/seq_device.c: In function 'snd_seq_device_dev_register':
sound/core/seq_device.c:163:41: error: suggest braces around empty body in an 'if' statement [-Werror=empty-body]
163 | queue_autoload_drivers();
Change them to empty inline functions, which are more robust here.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20210322103128.547199-1-arnd@kernel.org
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Add debug prints after calls of do_alloc_pages. One simplification would
be to move print into do_alloc_pages, however it would cause spam in
logs, as preallocate_pcm_pages loops over do_alloc_pages trying lower
values in case of failures.
Reviewed-by: Cezary Rojewski <cezary.rojewski@intel.com>
Signed-off-by: Amadeusz Sławiński <amadeuszx.slawinski@linux.intel.com>
Link: https://lore.kernel.org/r/20210318160618.2504068-2-amadeuszx.slawinski@linux.intel.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
There are a few places doing the same loop iterating all PCM
substreams belonging to the PCM object. Introduce a local helper
macro, for_each_pcm_substream(), to simplify the code.
Link: https://lore.kernel.org/r/20210206203656.15959-5-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Since commit d4cfb30fce ("ALSA: pcm: Set per-card upper limit of PCM
buffer allocations") snd_pcm_lib_preallocate_dma_free() is a single line
function that has one caller, which is another single line function.
Clean this up a bit and remove snd_pcm_lib_preallocate_dma_free() and
directly call do_free_pages() from snd_pcm_lib_preallocate_free(). This is
a bit less boilerplate.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Link: https://lore.kernel.org/r/20201218153400.18394-1-lars@metafoo.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Fix cppcheck warnings:
sound/core/pcm_memory.c:380:26: warning: Either the condition
'!substream' is redundant or there is possible null pointer
dereference: substream. [nullPointerRedundantCheck]
struct snd_card *card = substream->pcm->card;
^
sound/core/pcm_memory.c:384:6: note: Assuming that condition
'!substream' is not redundant
if (PCM_RUNTIME_CHECK(substream))
^
sound/core/pcm_memory.c:380:26: note: Null pointer dereference
struct snd_card *card = substream->pcm->card;
^
sound/core/pcm_memory.c:433:26: warning: Either the condition
'!substream' is redundant or there is possible null pointer
dereference: substream. [nullPointerRedundantCheck]
struct snd_card *card = substream->pcm->card;
^
sound/core/pcm_memory.c:436:6: note: Assuming that condition
'!substream' is not redundant
if (PCM_RUNTIME_CHECK(substream))
^
sound/core/pcm_memory.c:433:26: note: Null pointer dereference
struct snd_card *card = substream->pcm->card;
^
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20200902212133.30964-4-pierre-louis.bossart@linux.intel.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
This reverts commit 3ad796cbc3 ("ALSA: pcm: Use SG-buffer only when
direct DMA is available") also the modification commit 467fd0e82b
("ALSA: pcm: Fix build error on m68k and others").
Poking the DMA internal helper is a layer violation, so we should
avoid that. Meanwhile the actual bug has been addressed by the
Kconfig fix in commit dbed452a07 ("dma-pool: decouple DMA_REMAP from
DMA_COHERENT_POOL"), so we can live without this hack.
Link: https://lore.kernel.org/r/20200717064130.22957-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
The commit 3ad796cbc3 ("ALSA: pcm: Use SG-buffer only when direct
DMA is available") introduced a check of the DMA type and this caused
a build error on m68k (and possibly some others) due to the lack of
dma_is_direct() definition. Since the check is needed only for
CONFIG_SND_DMA_SGBUF enablement (i.e. solely x86), use #ifdef instead
of IS_ENABLED() for avoiding such a build error.
Fixes: 3ad796cbc3 ("ALSA: pcm: Use SG-buffer only when direct DMA is available")
Reported-by: kernel test robot <lkp@intel.com>
Link: https://lore.kernel.org/r/20200707111225.26826-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
The DMA-coherent SG-buffer is tricky to use, as it does need the
mapping. It used to work stably on x86 over years (and that's why we
had enabled SG-buffer on solely x86) with the default mmap handler and
vmap(), but our luck seems no forever success. The chance of breakage
is high when the special DMA handling is introduced in the arch side.
In this patch, we change the buffer allocation to use the SG-buffer
only when the device in question is with the direct DMA. It's a bit
hackish, but it's currently the only condition that may work (more or
less) reliably with the default mmap and vmap() for mapping the pages
that are deduced via virt_to_page().
In theory, we can apply the similar hack in the sound/core memory
allocation helper, too; but it's used by SOF for allocating SG pages
without re-mapping via vmap() or mmap, and it's fine to use it in that
way, so let's keep it and adds the workaround in PCM side.
Link: https://lore.kernel.org/r/20200615160045.2703-5-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Currently, the available buffer allocation size for a PCM stream
depends on the preallocated size; when a buffer has been preallocated,
the max buffer size is set to that size, so that application won't
re-allocate too much memory. OTOH, when no preallocation is done,
each substream may allocate arbitrary size of buffers as long as
snd_pcm_hardware.buffer_bytes_max allows -- which can be quite high,
HD-audio sets 1GB there.
It means that the system may consume a high amount of pages for PCM
buffers, and they are pinned and never swapped out. This can lead to
OOM easily.
For avoiding such a situation, this patch adds the upper limit per
card. Each snd_pcm_lib_malloc_pages() and _free_pages() calls are
tracked and it will return an error if the total amount of buffers
goes over the defined upper limit. The default value is set to 32MB,
which should be really large enough for usual operations.
If larger buffers are needed for any specific usage, it can be
adjusted (also dynamically) via snd_pcm.max_alloc_per_card option.
Setting zero there means no chceck is performed, and again, unlimited
amount of buffers are allowed.
Link: https://lore.kernel.org/r/20200120124423.11862-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
This patch adds the support for the feature to automatically allocate
and free PCM buffers, so called "managed buffer allocation" mode.
It's set up via new PCM helpers, snd_pcm_set_managed_buffer() and
snd_pcm_set_managed_buffer_all(), both of which correspond to the
existing preallocator helpers, snd_pcm_lib_preallocate_pages() and
snd_pcm_lib_preallocate_pages_for_all(). When the new helper is used,
it not only performs the pre-allocation of buffers, but also it
manages to call snd_pcm_lib_malloc_pages() before the PCM hw_params
ops and snd_lib_pcm_free() after the PCM hw_free ops inside PCM core,
respectively. This allows drivers to drop the explicit calls of the
memory allocation / release functions, and it will be a good amount of
code reduction in the end of this patch series.
When the PCM substream is set to the managed buffer allocation mode,
the managed_buffer_alloc flag is set in the substream object. Since
some drivers want to know when a buffer is newly allocated or
re-allocated at hw_params callback (e.g. want to set up the additional
stuff for the given buffer only at allocation time), now PCM core
turns on buffer_changed flag when the buffer has changed.
The standard conversions to use the new API will be straightforward:
- Replace snd_pcm_lib_preallocate*() calls with the corresponding
snd_pcm_set_managed_buffer*(); the arguments should be unchanged
- Drop superfluous snd_pcm_lib_malloc() and snd_pcm_lib_free() calls;
the check of snd_pcm_lib_malloc() returns should be replaced with
the check of runtime->buffer_changed flag.
- If hw_params or hw_free becomes empty, drop them from PCM ops
Link: https://lore.kernel.org/r/20191117085308.23915-2-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
The helper is no longer referred after the recent code refactoring.
Drop the export for saving some bits and future misuse.
Acked-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20191108094641.20086-9-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
It makes little sense to create prealloc proc files for streams that
have the zero max size, which is a typical case for vmalloc buffers.
Skip the proc file creations to save resources in such a case.
Link: https://lore.kernel.org/r/20191105191007.18150-3-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Warn if snd_pcm_lib_preallocate_pages*() is applied to the stream that
has already the preallocated buffers and skip the allocation. It's a
clearly a driver bug.
Link: https://lore.kernel.org/r/20191105191007.18150-2-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
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>
Now all callers no longer check the return value from
snd_pcm_lib_preallocate_pages() and co, let's make them to return
void, so that any new code won't fall into the same pitfall.
Reviewed-by: Jaroslav Kysela <perex@perex.cz>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
The calls of snd_info_register() are superfluous and should be avoided
at the procfs creation time. They are called at the end of the whole
initialization via snd_card_register(). This patch drops such
superfluous calls, as well as cleaning up the calls of substream proc
entries with a common helper.
Reviewed-by: Jaroslav Kysela <perex@perex.cz>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
The proc files are recursively freed by calling with the root
snd_info_entry object, so we don't have to keep each object for
releasing one by one. Move the release of the PCM stream proc root at
the beginning, so that we can remove the redundant code and resource.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Convert the S_<FOO> symbolic permissions to their octal equivalents as
using octal and not symbolic permissions is preferred by many as more
readable.
see: https://lkml.org/lkml/2016/8/2/1945
Done with automated conversion via:
$ ./scripts/checkpatch.pl -f --types=SYMBOLIC_PERMS --fix-inplace <files...>
Miscellanea:
o Wrapped one multi-line call to a single line
Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
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>
The failures of buffer preallocations at driver initializations aren't
critical but it's still helpful to inform, so that user can know that
something doesn't work as expected.
For example, the recent page allocator change triggered regressions,
but developers didn't notice until recently because the driver didn't
complain.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Nowadays we have CMA for obtaining the contiguous memory pages
efficiently. Let's kill the old kludge for reserving the memory pages
for large buffers. It was rarely useful (only for preserving pages
among module reloading or a little help by an early boot scripting),
used only by a couple of drivers, and yet it gives too much ugliness
than its benefit.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
script/kernel-doc reports the following type of warnings (when run in verbose
mode):
Warning(sound/core/init.c:152): No description found for return value of
'snd_card_create'
To fix that:
- add missing descriptions of function return values
- use "Return:" sections to describe those return values
Along the way:
- complete some descriptions
- fix some typos
Signed-off-by: Yacine Belkadi <yacine.belkadi.1@gmail.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Passing struct snd_dma_buffer pointer instead, so that they work no
matter whether real SG buffer is used or not.
This is a preliminary work for the HD-audio DSP loader code.
Signed-off-by: Ian Minett <ian_minett@creativelabs.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
These aren't modules, but they do make use of these macros, so
they will need export.h to get that definition. Previously,
they got it via the implicit module.h inclusion.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.
percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.
http://userweb.kernel.org/~tj/misc/slabh-sweep.py
The script does the followings.
* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.
* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.
* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.
The conversion was done in the following steps.
1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.
2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.
3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.
4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.
5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.
6. percpu.h was updated not to include slab.h.
7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).
* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig
8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.
Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
There are now five copies of the code to allocate a PCM buffer using
vmalloc(). Add a sixth in the core so that the others can be removed.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Using SG-buffers with dma_alloc_coherent() is often very inefficient
on non-coherent architectures because a tracking record could be
allocated in addition for each dma_alloc_coherent() call.
Instead, simply disable SG-buffers but just allocate normal continuous
buffers on non-supported (currently all but x86) architectures.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Most hardwares have limited buffer-descriptor table length. This
also restricts the max buffer size of the sound driver.
For example, snd-hda-intel has 1MB buffer size limit, and this is
because it can have at most 256 BDL entries. For supporting larger
buffers, we need to allocate larger pages even for sg-buffers.
This patch changes the sgbuf allocation code to try to allocate
larger pages first. At each head of the allocated pages, the
number of allocated pages is stored in the lowest bits of the
corresponding entry of the table addr field. This change isn't
visible as long as the driver uses snd_sgbuf_get_addr() helper.
Also, the patch adds a new function, snd_pcm_sgbuf_get_chunk_size().
This returns the size of the chunk on continuous pages starting at
the given position offset. If the chunk reaches to a non-continuous
page, it returns the size to the boundary.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@perex.cz>
Kill snd_assert() in sound/core/*, either removed or replaced with
if () with snd_BUG_ON().
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@perex.cz>
This header file exists only for some hacks to adapt alsa-driver
tree. It's useless for building in the kernel. Let's move a few
lines in it to sound/core.h and remove it.
With this patch, sound/driver.h isn't removed but has just a single
compile warning to include it. This should be really killed in
future.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@perex.cz>
- Add the linked list to each proc entry to enable a single-shot
disconnection (unregister)
- Deprecate snd_info_unregister(), use snd_info_free_entry()
- Removed NULL checks of snd_info_free_entry()
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@suse.cz>
