How gregkh/linux works
Linux is the operating-system kernel: it exposes services to userspace, coordinates hardware, and provides shared frameworks used by device drivers. The supplied files show representative architecture support, asynchronous DMA and crypto, SPI, USB mass storage, IIO buffering, and graphics/display pipelines. The principal visible flow is a kernel client requesting asynchronous device work through a framework and receiving completion; other files show syscall entry and hardware-specific control. The excerpts are partial, so links between broader kernel subsystems are omitted where their callers are not evidenced.
Main entry points: dmaengine.c DMAengine framework · guarded_storage.c Guarded storage syscall · crypto_engine.c Crypto engine queue · industrialio-buffer-dmaengine.c IIO DMA buffer
Components 17
Architecture support
- Guarded storage syscall
arch/s390/kernel/guarded_storage.c - Alpha platform support
arch/alpha/kernel/setup.c - ARC platform support
arch/arc/kernel/setup.c - ARM platform support
arch/arm/kernel/setup.c
Kernel frameworks
- DMAengine framework
drivers/dma/dmaengine.c - Crypto engine queue
crypto/crypto_engine.c - IIO DMA buffer
drivers/iio/buffer/industrialio-buffer-dmaengine.c
Device drivers
- AMD CCP DMA
drivers/crypto/ccp/ccp-dmaengine.c - AMD passthrough DMA
drivers/dma/amd/ptdma/ptdma-dmaengine.c - AXI SPI controller
drivers/spi/spi-axi-spi-engine.c - USB mass storage
drivers/usb/gadget/function/f_mass_storage.c - APU board GPIO
drivers/platform/x86/pcengines-apuv2.c
Graphics and display
- Intel i915 engines
drivers/gpu/drm/i915/gt/intel_engine_cs.c - Intel Xe engines
drivers/gpu/drm/xe/xe_hw_engine.c - Komeda display pipeline
drivers/gpu/drm/arm/display/komeda/komeda_pipeline_state.c
Other components
- Userspace process
- Hardware devices
Connections 12
- Userspace process → Guarded storage syscall: invokes syscall
- Guarded storage syscall → Hardware devices: programs controls
- IIO DMA buffer → DMAengine framework: requests transfers
- AMD CCP DMA → DMAengine framework: registers channels
- AMD passthrough DMA → DMAengine framework: registers channels
- AXI SPI controller → Hardware devices: programs controller
- USB mass storage → Hardware devices: serves USB requests
- Intel i915 engines → Hardware devices: controls engines
- Intel Xe engines → Hardware devices: programs engines
- Komeda display pipeline → Hardware devices: updates components
- APU board GPIO → Hardware devices: configures GPIO
- Crypto engine queue → Hardware devices: queues engine work