Re: [PATCH v5 3/6] dma: swiotlb: Centralize minimal pool sizing
From: Catalin Marinas <catalin.marinas@arm.com>
Date: 2026-09-21 12:52:38
Also in:
linux-iommu, linux-mips, linux-riscv, linux-s390, linuxppc-dev, lkml, loongarch
On Mon, Sep 21, 2026 at 12:06:25PM +0530, Aneesh Kumar K.V (Arm) wrote:
A default SWIOTLB pool used only for unaligned kmalloc bouncing can be smaller than one required for limited DMA addressing. Arm64 and RISC-V currently implement this sizing independently, using 1 MiB of SWIOTLB space per GiB of RAM. The SWIOTLB core now identifies this case with SWIOTLB_POOL_MINIMAL. Size that policy in swiotlb_adjust_pool_size() and remove the architecture-specific adjustments. Explicit swiotlb= sizing remains unchanged because swiotlb_adjust_size() preserves a user-configured size. Signed-off-by: Aneesh Kumar K.V (Arm) <aneesh.kumar@kernel.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>