25723d6636
The unit.* code is largely obsolete and imposes limits that are no longer needed nowadays. - Capping the maximum allowed soundcards in a given machine. By default, the limit is 512 (snd_max_u() in unit.c), and the maximum possible is 2048 (SND_UNIT_UMAX in unit.h). It can also be tuned through the hw.snd.maxunit loader(8) tunable. Even though these limits are large enough that they should never cause problems, there is no need for this limit to exist in the first place. - Capping the available device/channel types. By default, this is 32 (snd_max_d() in unit.c). However, these types are pre-defined in pcm/sound.h (see SND_DEV_*), so the cap is unnecessary when we know that their number is constant. - Capping the number of channels per-device. By default, the limit 1024 (snd_max_c() in unit.c). This is probably the most problematic of the limits mentioned, because this limit can never be reached, as the maximum is hard-capped at either hw.snd.maxautovchans (16 by default), or SND_MAXHWCHAN and SND_MAXVCHANS. These limtits are encoded in masks (see SND_U_MASK, SND_D_MASK, SND_C_MASK in unit.h) and are used to construct a bitfield of the form [dsp_unit, type, channel_unit] in snd_mkunit() which is assigned to pcm_channel->unit. This patch gets rid of everything unit.*-related and makes a slightly different use of the "unit" field to only contain the channel unit number. The channel type is stored in a new pcm_channel->type field, and the DSP unit number need not be stored at all, since we can fetch it from device_get_unit(pcm_channel->dev). This change has the effect that we no longer need to impose caps on the number of soundcards, device/channel types and per-device channels. As a result the code is noticeably simplified and more readable. Apart from the fact that the hw.snd.maxunit loader(8) tunable is also retired as a side-effect of this patch, sound(4)'s behavior remains the same. Sponsored by: The FreeBSD Foundation MFC after: 1 week Reviewed by: dev_submerge.ch Differential Revision: https://reviews.freebsd.org/D44912 |
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| .cirrus-ci | ||
| .github | ||
| bin | ||
| cddl | ||
| contrib | ||
| crypto | ||
| etc | ||
| gnu | ||
| include | ||
| kerberos5 | ||
| lib | ||
| libexec | ||
| release | ||
| rescue | ||
| sbin | ||
| secure | ||
| share | ||
| stand | ||
| sys | ||
| targets | ||
| tests | ||
| tools | ||
| usr.bin | ||
| usr.sbin | ||
| .arcconfig | ||
| .arclint | ||
| .cirrus.yml | ||
| .clang-format | ||
| .git-blame-ignore-revs | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| CONTRIBUTING.md | ||
| COPYRIGHT | ||
| LOCKS | ||
| MAINTAINERS | ||
| Makefile | ||
| Makefile.inc1 | ||
| Makefile.libcompat | ||
| Makefile.sys.inc | ||
| ObsoleteFiles.inc | ||
| README.md | ||
| RELNOTES | ||
| UPDATING | ||
FreeBSD Source:
This is the top level of the FreeBSD source directory.
FreeBSD is an operating system used to power modern servers, desktops, and embedded platforms. A large community has continually developed it for more than thirty years. Its advanced networking, security, and storage features have made FreeBSD the platform of choice for many of the busiest web sites and most pervasive embedded networking and storage devices.
For copyright information, please see the file COPYRIGHT in this directory. Additional copyright information also exists for some sources in this tree - please see the specific source directories for more information.
The Makefile in this directory supports a number of targets for building components (or all) of the FreeBSD source tree. See build(7), config(8), FreeBSD handbook on building userland, and Handbook for kernels for more information, including setting make(1) variables.
For information on the CPU architectures and platforms supported by FreeBSD, see the FreeBSD website's Platforms page.
Source Roadmap:
| Directory | Description |
|---|---|
| bin | System/user commands. |
| cddl | Various commands and libraries under the Common Development and Distribution License. |
| contrib | Packages contributed by 3rd parties. |
| crypto | Cryptography stuff (see crypto/README). |
| etc | Template files for /etc. |
| gnu | Commands and libraries under the GNU General Public License (GPL) or Lesser General Public License (LGPL). Please see gnu/COPYING and gnu/COPYING.LIB for more information. |
| include | System include files. |
| kerberos5 | Kerberos5 (Heimdal) package. |
| lib | System libraries. |
| libexec | System daemons. |
| release | Release building Makefile & associated tools. |
| rescue | Build system for statically linked /rescue utilities. |
| sbin | System commands. |
| secure | Cryptographic libraries and commands. |
| share | Shared resources. |
| stand | Boot loader sources. |
| sys | Kernel sources (see sys/README.md). |
| targets | Support for experimental DIRDEPS_BUILD |
| tests | Regression tests which can be run by Kyua. See tests/README for additional information. |
| tools | Utilities for regression testing and miscellaneous tasks. |
| usr.bin | User commands. |
| usr.sbin | System administration commands. |
For information on synchronizing your source tree with one or more of the FreeBSD Project's development branches, please see FreeBSD Handbook.