660cd44659
[WHY] 1. Drivers using DRM_GEM_SHADOW_PLANE_HELPER_FUNCS and DRM_GEM_SHMEM_DRIVER_OPS (e.g., udl, ast) do not require sg_table import. They only need dma_buf_vmap() to access the shared buffer's kernel virtual address. 2. On certain Aspeed-based boards, a dma_mask of 0xffff_ffff may trigger SWIOTLB during dmabuf import. However, IO_TLB_SEGSIZE restricts the maximum DMA streaming mapping memory, resulting in errors like: ast 0000:07:00.0: swiotlb buffer is full (sz: 3145728 bytes), total 32768 (slots), used 0 (slots) [HOW] Provide a gem_prime_import implementation without sg_table mapping to avoid issues (e.g., "swiotlb buffer is full"). Drivers that do not require sg_table can adopt this. Signed-off-by: Shixiong Ou <oushixiong@kylinos.cn> Acked-by: Thomas Zimmermann <tzimmermann@suse.de> Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> Link: https://lore.kernel.org/r/20250522070714.439824-1-oushixiong1025@163.com |
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| Documentation | ||
| LICENSES | ||
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| io_uring | ||
| ipc | ||
| kernel | ||
| lib | ||
| mm | ||
| net | ||
| rust | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .clippy.toml | ||
| .cocciconfig | ||
| .editorconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| .rustfmt.toml | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
README
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the reStructuredText markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.