6482c22ec0
This patch changes the mem_pool implementation to track the last two allocations (instead of just the last) and allow them both to be freed if the mem_pool_free() calls come in in reverse order. This is intended as a specific optimization for the CBFS cache case when a compressed file is mapped on a platform that doesn't natively support memory-mapping flash. In this case, cbfs_map() (chaining through to _cbfs_alloc() with allocator == NULL) will call mem_pool_alloc(&cbfs_cache) to allocate space for the uncompressed file data. It will then call cbfs_load_and_decompress() to fill that allocation, which will notice the compression and in turn call rdev_mmap_full() to map the compressed data (which on platforms without memory-mapped flash usually results in a second call to mem_pool_alloc(&cbfs_cache)). It then runs the decompression algorithm and calls rdev_munmap() on the compressed data buffer (the latter one in the allocation sequence), leading to a mem_pool_free(). The remaining buffer with the uncompressed data is returned out of cbfs_map() to the caller, which should eventually call cbfs_unmap() to mem_pool_free() that as well. This patch allows this simple case to succeed without leaking any permanent allocations on the cache. (More complicated cases where the caller maps other files before cbfs_unmap()ing the first one may still lead to leaks, but those are very rare in practice.) Signed-off-by: Julius Werner <jwerner@chromium.org> Change-Id: Ic5c4c56a8482752ed65e10cf35565f9b2d3e4b17 Reviewed-on: https://review.coreboot.org/c/coreboot/+/52087 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Aaron Durbin <adurbin@chromium.org> |
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| 3rdparty | ||
| configs | ||
| Documentation | ||
| LICENSES | ||
| payloads | ||
| src | ||
| tests | ||
| util | ||
| .checkpatch.conf | ||
| .clang-format | ||
| .editorconfig | ||
| .gitignore | ||
| .gitmodules | ||
| .gitreview | ||
| AUTHORS | ||
| COPYING | ||
| gnat.adc | ||
| MAINTAINERS | ||
| Makefile | ||
| Makefile.inc | ||
| README.md | ||
| toolchain.inc | ||
coreboot README
coreboot is a Free Software project aimed at replacing the proprietary BIOS (firmware) found in most computers. coreboot performs a little bit of hardware initialization and then executes additional boot logic, called a payload.
With the separation of hardware initialization and later boot logic, coreboot can scale from specialized applications that run directly firmware, run operating systems in flash, load custom bootloaders, or implement firmware standards, like PC BIOS services or UEFI. This allows for systems to only include the features necessary in the target application, reducing the amount of code and flash space required.
coreboot was formerly known as LinuxBIOS.
Payloads
After the basic initialization of the hardware has been performed, any desired "payload" can be started by coreboot.
See https://www.coreboot.org/Payloads for a list of supported payloads.
Supported Hardware
coreboot supports a wide range of chipsets, devices, and mainboards.
For details please consult:
Build Requirements
- make
- gcc / g++
Because Linux distribution compilers tend to use lots of patches. coreboot
does lots of "unusual" things in its build system, some of which break due
to those patches, sometimes by gcc aborting, sometimes - and that's worse -
by generating broken object code.
Two options: use our toolchain (eg. make crosstools-i386) or enable the
ANY_TOOLCHAINKconfig option if you're feeling lucky (no support in this case). - iasl (for targets with ACPI support)
- pkg-config
- libssl-dev (openssl)
Optional:
- doxygen (for generating/viewing documentation)
- gdb (for better debugging facilities on some targets)
- ncurses (for
make menuconfigandmake nconfig) - flex and bison (for regenerating parsers)
Building coreboot
Please consult https://www.coreboot.org/Build_HOWTO for details.
Testing coreboot Without Modifying Your Hardware
If you want to test coreboot without any risks before you really decide to use it on your hardware, you can use the QEMU system emulator to run coreboot virtually in QEMU.
Please see https://www.coreboot.org/QEMU for details.
Website and Mailing List
Further details on the project, a FAQ, many HOWTOs, news, development guidelines and more can be found on the coreboot website:
You can contact us directly on the coreboot mailing list:
https://www.coreboot.org/Mailinglist
Copyright and License
The copyright on coreboot is owned by quite a large number of individual developers and companies. Please check the individual source files for details.
coreboot is licensed under the terms of the GNU General Public License (GPL). Some files are licensed under the "GPL (version 2, or any later version)", and some files are licensed under the "GPL, version 2". For some parts, which were derived from other projects, other (GPL-compatible) licenses may apply. Please check the individual source files for details.
This makes the resulting coreboot images licensed under the GPL, version 2.