block uses ISA_DMA_THRESHOLD for BLK_BOUNCE_ISA. Only SCSI uses ISA_DMA_THRESHOLD for ancient drivers with non-zero unchecked_isa_dma. Nowadays drivers (and subsystems) use dma_mask properly instead of ISA_DMA_THRESHOLD. Documentation/scsi/scsi_mid_low_api.txt says: unchecked_isa_dma - 1=>only use bottom 16 MB of ram (ISA DMA addressing restriction), 0=>can use full 32 bit (or better) DMA address space So block simply uses DMA_BIT_MASK(24) for BLK_BOUNCE_ISA for SCSI. Signed-off-by: FUJITA Tomonori <fujita.tomonori@xxxxxxxxxxxxx> --- include/linux/blkdev.h | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 8b7f5e0..f95bdd1 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -709,7 +709,7 @@ extern unsigned long blk_max_low_pfn, blk_max_pfn; #define BLK_BOUNCE_HIGH -1ULL #endif #define BLK_BOUNCE_ANY (-1ULL) -#define BLK_BOUNCE_ISA (ISA_DMA_THRESHOLD) +#define BLK_BOUNCE_ISA (DMA_BIT_MASK(24)) /* * default timeout for SG_IO if none specified -- 1.6.5 -- To unsubscribe from this list: send the line "unsubscribe linux-arch" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html