unsafe_ops

unsafe_ops is a low-level utility library designed to provide direct access to hardware and memory operations. It is tailored for developers working on embedded systems, operating systems, and performance-critical applications where low-level control and performance optimization are crucial.

• Instruction Injection
  • Injection of instruction sequence on the host CPU directly and dynamically on runtime.
• Direct Hardware I/O Access
  • Read and write to hardware ports (e.g., port_read8, port_write8).
• Memory Operations
  • Allocate, align, and protect memory regions for specific purposes (e.g., executable memory or read-only memory).
  • Support for cache control operations (e.g., flushing and prefetching).
• Endianness Handling
  • Convert between big-endian and little-endian formats for buffers and individual values.
• Interrupt Handling
  • Simplify device interrupt handling with callbacks and status register manipulation.
• Volatile Operations
  • Atomic read and write operations on volatile memory regions.

Supported Platforms

The unsafe_ops library is designed to be portable across several architectures and platforms, as evidenced by its use of architecture-specific assembly instructions and fallback implementations.

Architectures

• x86 and x86_64 (Intel/AMD)
  • Utilizes mfence, lfence, and sfence instructions for memory barriers.
  • Implements cache operations using the clflush instruction.
• ARM and AArch64
  • Uses dmb instructions for memory barriers (ish, ishld, ishst).
  • Implements cache operations with dc instructions (ivac, cvac, civac).
• RISC-V
  • Supports cache operations with optional ZICBOM extensions (e.g., cbo.inval, cbo.clean, cbo.flush).
  • Provides fallback options using fence instructions (fence.i, fence ow,ow).

Operating Systems

On Linux, unsafe_ops was tested with sysconf for retrieving page size and cache line size. Implementation of DMA functionality is using system headers like sched.h, sys/mman.h, and unistd.h.

Requirements

• Compiler GCC or Clang with support for inline assembly and architecture-specific extensions.
• Hardware A CPU that supports one of the aforementioned architectures.

Notes

1. The library includes fallback implementations using __sync_synchronize() for platforms without specific memory barrier instructions.
2. Cache and memory operations may be hardware-specific and should be used with caution, ensuring compatibility with the target hardware.

Disclaimer

unsafe_ops provides low-level access to system resources and hardware. Misuse of these operations can lead to crashes, data corruption, or hardware damage. Use responsibly and test thoroughly in controlled environments.

License

Copyright (c) 2025 - Nathanne Isip

unsafe_ops is licensed under the GNU General Public License v3. You are free to use, modify, and distribute this library under the terms of the license.