On Mon, Apr 07, 2025 at 02:46:32PM +0100, Keith Busch wrote: > > > - Is is possible to have segments not even aligned to SECTOR_SIZE? > > > > No. > > O_DIRECT only requires each user iovec be a multiple of the logical > block size with the address aligned to the dma_alignment. If the > dma_alignment is smaller than the logical block size, then this could > create bvec segments that are smaller. For nvme where we have 4-byte > dma alignment, you could have the first segment be the last 4 bytes of a > page, then the remaing 508 bytes from a different page in the next > segment. Oh, right - with a smaller dma alignment this can actually happen.
