spdk-rs crate

spdk-rs crate provides a higher-level bindings and wrappers around SPDK library to enable building safer SPDK-based Rust applications.

Getting SPDK library

Read about SPDK here: https://spdk.io/.

spdk-rs crate requires SPDK library to exist on the system. spdk-rs supports both linking to an SPDK library installed system-wide, or to SPDK libraries and headers located in the SPDK build directory.

spdk-rs uses SPDK_PATH environment variable to locate SPDK. If it is not set, spdk-rs tries to find SPDK in spdk-rs/spdk directory.

In order to get SPDK on the system, one can either use the Nix scripts provided by Mayastor, or build SPDK manually. Installing SPDK via system's package managers like apt is not fully supported. It may, or may not work.

Currently, spdk-rs can only link to SPDK built as static libraries.

About linking SPDK applications: https://spdk.io/doc/pkgconfig.html.

Using Nix scripts provided by Mayastor

Enter the Nix shell provided by Mayastor:

nix-shell

When you do it for the first time, it would require some time to Nix to build SPDK and all required dependencies, and configure the environment to use them.

Now, build spdk-rs with Cargo:

cd spdk-rs
cargo build

Building SPDK manually

When making changes (or debugging) SPDK, it is often more convenient to have a local checkout of SPDK rather than dealing with packages.

In order to have all other dependencies (except SPDK) properly installed, start Mayastor Nix shell with SPDK package disabled:

nix-shell --arg nospdk true

Alternatively, it is possible to install all the dependencies required by SPDK manually. These steps are not covered in this manual.

Now, clone and checkout a supported version of SPDK:

mkdir ${your_spdk_dir}
cd ${your_spdk_dir}
git checkout vYY.mm.x-mayastor
git submodule update --init --recursive

Configure and build it:

./configure --enable-debug --target-arch=nehalem --without-shared \
    --without-isal --with-crypto --with-uring --disable-unit-tests \
    --disable-tests --with-fio=$(which fio | sed s';bin/fio;include;')
make

---

NOTE

Currently, SPDK's make install script does not make an installation sutiable to be used with spdk-rs. That is, trying to configure (via DESTDIR) and install SPDK in other directory using Makefile is not supported.

---

After build, SPDK can be used to build spdk-rs. Either set SPDK_PATH, or create a symlink in spdk-rs directory to point to your SPDK.

export SPDK_PATH=${your_spdk_dir}

or

cd ${workspace}/spdk-rs
ln -s ${your_spdk_dir} ./spdk

Alternatively, one can clone SPDK inside spdk-rs and use the proivided build_spdk.sh script to build it.

Cleaning SPDK build

To clean up the SPDK directory and reset to the initial state:

mkdir ${your_spdk_dir}
make clean
git clean -fdx ./
git submodule foreach --recursive git clean -xfd
git submodule update

Revert to Nix SPDK

To go back to SPDK library installed by Nix, exit the nospdk Nix shell and start it again with:

nix-shell

SPDK_PATH variable takes precedence over SPDK found in spdk-rs/spdk, so no need to remove or rename it.