7637de311b
When running a NVMe device that is attached to a addressing challenged PCIe root port that requires bounce buffering, our request sizes can easily overflow the swiotlb bounce buffer size. Limit the maximum I/O size to the limit exposed by the DMA mapping subsystem. Signed-off-by: Christoph Hellwig <hch@lst.de> Reported-by: Atish Patra <Atish.Patra@wdc.com> Tested-by: Atish Patra <Atish.Patra@wdc.com> Reviewed-by: Sagi Grimberg <sagi@grimberg.me>