Posts

How Linux DRM shares buffers between processes and devices with PRIME and dma-buf: handle to fd export, fd to handle import, the dma_buf_ops table, and a dumb buffer plus PRIME example.

How Linux DRM manages GPU buffers with GEM: drm_gem_object, per-file handles, dumb buffer creation and the mmap fake offset path with page faults in Linux v6.19.

The code path of open() and ioctl() in Linux DRM v6.19: drm_stub_open, drm_file_alloc, drm_ioctl dispatch and permission checks, plus a libdrm probe example.

How Linux DRM comes up: drm_core_init registers major number 226, and a driver such as vkms creates its /dev/dri nodes through drm_dev_init and drm_dev_register in Linux v6.19.

An overview of the Linux Direct Rendering Manager (DRM): why it exists, the user and kernel stack, the /dev/dri device nodes, and the core structures drm_driver, drm_device and drm_file in Linux v6.19.

Understanding and using the $RANDOM internal variable in Bash, including its open-source implementation