
The old implementation was based on an ancient copy of the FreeBSD busdma code for x86, and did not make a bunch of assumptions that we make basically everywhere else (for instance, that we can request arbitrarily-aligned contiguous physical memory from the VM.) As a consequence, it had a significant amount of code devoted to bounce pages, which are just a waste of resources on x86, and for that matter, probably any other architecture Haiku will ever be ported to. (Even if we do need to run on some system where only a small portion of system memory can be accessed by devices, likely we would reserve that memory for just this occasion anyway.) I was initially under the impression that the bounce-pages code never turned on, but apparently due to the "alignment" check (and also the "Maxmem" check, which was to defined to 32KB...?!) it does indeed activate on a variety of systems, and maybe (in the case of drivers that do not call sync() properly) even is the cause of some of our ported driver breakage. The new implementation is pretty much optimized for Haiku, and shares almost no code or structure with the old one (save for a few functions that really only have one proper implementation.) Tested with ipro1000 and rtl81xx. Regressions are more than possible, so please don't hesitate to file bugs if your network driver now fails to come up (or you get KDLs.)
Haiku
Homepage | Mailing Lists | IRC Channels | Issue Tracker | API docs
Haiku is an open-source operating system that specifically targets personal computing. Inspired by the BeOS, Haiku is fast, simple to use, easy to learn and yet very powerful.
Goals
- Sensible defaults with minimal configuration required.
- Clean, clear, concise code.
- Unified desktop environment.
Trying Haiku
Haiku provides pre-built nightly images and release images. Haiku is compatible with a large variety of hardware, but in case you don't want to "take the plunge" and install Haiku on bare metal, you can install it on a virtual machine (VM) instead. If you've never used a VM before, you can follow one of the "Emulating Haiku" guides.
Compiling Haiku
See ReadMe.Compiling
.
Contributing
Haiku is a meritocratic open source project with a large variety of tasks. Even if you can't write code, you can still help! Haiku needs designers, (technical) writers, translators, testers... Get involved and help out!
Contributing code
If you're submitting a patch to us, please make sure you're following the patch submitting guidelines.
If you're having trouble finding something in the source tree, you can use one of our web-based source code browsers:
- http://xref.plausible.coop/ (OpenGrok, provided by Landon Fuller)
- http://cgit.haiku-os.org/ (cgit, provided by Haiku, Inc.)
Contributing documentation
The main piece of documentation that still needs work are the API docs (found
in the tree at docs/user
). Just find an undocumented class, write
documentation for it, and submit a patch.
Contributing translations
See wiki:i18n.
Contributing software ports
See HaikuPorts.
Contributing to our infrastructure
See Infrastructure.