Logan, > +/* > + * bit 2 is the third free bit in the page_link on 64bit systems which > + * is used by dma_unmap_sg() to determine if the dma_address is a PCI > + * bus address when doing P2PDMA. > + * Note: CONFIG_PCI_P2PDMA depends on CONFIG_64BIT because of this. > + */ > + > +#ifdef CONFIG_PCI_P2PDMA > +#define SG_DMA_PCI_P2PDMA 0x04UL > +#else > +#define SG_DMA_PCI_P2PDMA 0x00UL > +#endif > + > +#define SG_PAGE_LINK_MASK (SG_CHAIN | SG_END | SG_DMA_PCI_P2PDMA) > + You are doing two things in one patch :- 1. Introducing a new macro to replace the current macros. 2. Adding a new member to those macros. shouldn't this be split into two patches where you introduce a macro SG_PAGE_LINK_MASK (SG_CHAIN | SG_END) in prep patch and update the SF_PAGE_LINK_MASK with SG_DMA_PCI_P2PDMA with related code? OR Is there a reason why it is not split ? -ck
