drivers/dma/ioat · keep-annotate

Intel I/OAT DMA engines on Xeon server chipsets

Intel's I/O Acceleration Technology (I/OAT) is a DMA copy engine built into Xeon server chipsets from the mid-2000s through the Ice Lake generation, used to offload memory-to-memory copies (notably for the network stack and RAID) from the CPU. It covers I/OAT versions 3 through 3.4 found in enterprise servers shipped roughly 2007 to 2021.

keep-annotate conf=0.77 last_sold=2021 deploy=medium replacement=idxd subsystem=dma category=bus-other

77%

recommendation

Worth keeping but document its niche because the hardware is legacy Xeon silicon (PCI IDs stop at Ice Lake-class parts, with no new chips shipping since around 2021) and Intel's newer accelerators have moved to the separate idxd driver. MAINTAINERS lists the area as "Odd fixes" but the tree still saw roughly 21 substantive commits from 16 contributors over the last five years, so it is clearly maintained for the large installed base of Xeon servers still in production.

repository signals

9 files

4,681 source lines

26 commits, 5y

+80 / −93 lines added / removed, 5y

21 authors, 5y

monthly commits · 2021-04-21 → 2026-04-21 · 26 total · active in 15/61 months

sources

git.kernel.org
The driver identifies itself as the Intel I/OAT DMA Linux driver and its PCI ID table tops out at Intel IOAT ICX, indicating support is tied to older Xeon generations rather than current accelerator blocks.
git.kernel.org
`CONFIG_INTEL_IOATDMA` is described as support for the Intel I/OAT DMA engine in recent Intel Xeon chipsets, while the same Kconfig also exposes `CONFIG_INTEL_IDXD` for newer Intel Data Accelerators, making `idxd` the natural successor for new deployments.
git.kernel.org
The async transfers/transforms IOAT area is still listed in MAINTAINERS but marked `Odd fixes`, which fits a legacy-but-not-abandoned support posture.

codex reasoning notes (technical)

`exec_command` inspection of local tree files showed IOAT-specific PCI IDs through ICX and Kconfig/MAINTAINERS status; URLs are canonical-recall kernel.org mirrors of those inspected files. `lore_file_timeline` on `drivers/dma/ioat/` returned no matches (directory-prefix blind spot likely), and follow-up lore queries timed out, so upstream-activity judgment falls back to the user-provided stats: 21 substantive commits in 5y, 16 authors, last substantive touch 2025-08-27. That is too active for deprecate/remove, but the hardware family is clearly legacy server silicon, so keep the driver with an annotation that it mainly serves installed-base Xeon systems while new Intel acceleration has moved to `idxd`.