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 1rooxC6G 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08:36:59PM +0300, Leon Romanovsky wrote: > > > > diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h > > > > index 09b99d52fd36..283058bcb5b1 100644 > > > > --- a/include/linux/blk_types.h > > > > +++ b/include/linux/blk_types.h > > > > @@ -387,6 +387,7 @@ enum req_flag_bits { > > > > __REQ_FS_PRIVATE, /* for file system (submitter) use */ > > > > __REQ_ATOMIC, /* for atomic write operations */ > > > > __REQ_P2PDMA, /* contains P2P DMA pages */ > > > > + __REQ_MMIO, /* contains MMIO memory */ > > > > /* > > > > * Command specific flags, keep last: > > > > */ > > > > @@ -420,6 +421,7 @@ enum req_flag_bits { > > > > #define REQ_FS_PRIVATE (__force blk_opf_t)(1ULL << __REQ_FS_PRIVATE) > > > > #define REQ_ATOMIC (__force blk_opf_t)(1ULL << __REQ_ATOMIC) > > > > #define REQ_P2PDMA (__force blk_opf_t)(1ULL << __REQ_P2PDMA) > > > > +#define REQ_MMIO (__force blk_opf_t)(1ULL << __REQ_MMIO) > > > > > > Now that my integrity metadata DMA series is staged, I don't think we > > > can use REQ flags like this because data and metadata may have different > > > mapping types. I think we should add a flags field to the dma_iova_state > > > instead. > > > > Before integrity metadata code was merged, the assumption was that request is > > only one type or p2p or host. Is it still holding now? > > I don't think that was ever the case. Metadata is allocated > independently of the data payload, usually by the kernel in > bio_integrity_prep() just before dispatching the request. The bio may > have a p2p data payload, but the integrity metadata is just a kmalloc > buf in that path. Then you should do two dma mapping operations today, that is how the API was built. You shouldn't mix P2P and non P2P within a single operation right now.. Jason