FreeBSD

System Configuration

To use the FreeBSD backend you need to be running FreeBSD. xNVMe is likely to work on multiple different versions of FreeBSD, however to ensure compatibility we recommend using a version listed in the Toolchain section.

Device Identification

FreeBSD exposes NVMe devices as files using the following naming schemes:

/dev/nvme{ctrlr_id}

NVMe Controller device node

/dev/nvme{ctrlr_id}ns{ns_id}

NVMe Namespace as device node

/dev/nda{num}

NVMe Namespace as storage device node

/dev/nvd{num}

NVMe Namespace as disk drive

For details see the man-pages for nvme, nda, nvd, pci, disk, and nvmecontrol.

Backend Instrumentation

The backend identifier for the FreeBSD backend is: fbsd. The FreeBSD backend encapsulates the interfaces below. Some of these are mix-ins from the Common-Backend Implementations. For these, links point to descriptions in the CBI section. For the FreeBSD-specific interfaces, descriptions are available in the corresponding subsections.

• Memory Allocators

  • posix`, Use libc malloc()/free() with sysconf() for alignment, add link to CBI

• Asynchronous Interfaces

  • kqueue, Use kqueue based aio for Asynchronous I/O

  • posix, add link to CBI

  • emu, add link to CBI

  • thrpool, add link to CBI

  • nil, add link to CBI

• Synchronous Interfaces

  • nvme, Use FreeBSD NVMe Driver ioctl() for synchronous I/O

  • psync, Use pread()/write() for synchronous I/O

• Admin Interfaces

  • nvme, Use FreeBSD NVMe Driver ioctl() for admin commands

• Device Interfaces

  • fbsd, Use FreeBSD file/dev handles and enumerate NVMe devices