On 12/06/2025 07.02, Christoph Hellwig wrote: > On Wed, Jun 11, 2025 at 02:15:10PM +0200, Daniel Gomez wrote: >>> #define NVME_MAX_SEGS \ >>> - min(NVME_CTRL_PAGE_SIZE / sizeof(struct nvme_sgl_desc), \ >>> - (PAGE_SIZE / sizeof(struct scatterlist))) >>> + (NVME_CTRL_PAGE_SIZE / sizeof(struct nvme_sgl_desc)) >> >> The 8 MiB max transfer size is only reachable if host segments are at least 32k. >> But I think this limitation is only on the SGL side, right? > > Yes, PRPs don't really have the concept of segments to start with. SGLs don't have the same MPS limitation we have in PRPs. So I think the correct calculation for NVME_MAX_SEGS is PAGE_SIZE / sizeof(struct nvme_sgl_desc).
