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U2FsdGVkX19hj0RALfRZLIeCMLX6+meeN1fUPw72UqBVff0PeaadCqBBEIO4QUHvh5J+vIo5zakTET4wTOFr8zZwHSIkacXVM7O+FMzbwB5Bsf0lTlpEog65X+jSXcioqfhl1UFVonAlvvV390es8esWAlLjLP0mrDCy7ffe5c+cFcZ8yV5t/fyOOL7DwVlC6e+Vc9/QjhyyGrF0cUG+Uf5CzxDmjYBG6byUQB/OFtAiRvMn/5Eh2u/6P5voKgJe+Zb6FI/shnBD1k0vpXBthkgRLg/zyzE4QRg8aPtOxbdoGSZSo4m1bNlqktQuk9tSg+uqcoM695ZiiRKvfWi1G+xcVLYSHDfRT1mbwab+JkaE8Z6rtx+aniAbquOVqcbLmHSWe7EFITw44mbBG2Xh2Ig/iigWUA0UTl7XQexcVkEgCmVJv0vtYbEWCtgTRT7vFU44ZtbnDgVFBg7miPFZocloMBB+7evQyiyEyeT7FEJhg0Og15tPKcU2KwX9gtxqpajSiuJsOw2KmGIFyB98BUi0z6Ab6W4k4NXzYjeg+MeCZu2Y1yj+MSC5Bo/skGYrzqYGmixUpP3W4CXvnCvDj9posJmiH2uiK70J/kHW57zuYA5aOYjs7Q4oicXdBjh1P6nQW7JYlioFnPUl2pOkql20wFk6w9WNoEWbE8sY+0PZTHeLOtPEklB6VF0t0TkQboCV5qiRiiaGZpodHpimbG09UabyKKqJ3zo/DtHMuZ9b3bjDeuwFJOLVOkWQ4HHNjYnE8V3+w4S/hkDLQ6tSGegJrTE02DuIPz4XiZboYssU/NvtSYjQFNdp+ItGdQFkRnyDuV9mFPi2QFAO+hCjHYCc+lEfhkbexSsYxOXvD8QHDVlOVDWa6zq2Zck2f/GnH2rOkWf/HxAUdvbg2baNjfgmwyz1UkeDOmWfbwxpdwA4TAuv+vLlGqfdhWAcMKJu4jc0t8jl5+Nugq/nbqs tjVrNejA hLgXpWOKTg/cNHK/oST3bulxsElig1sKYsvrWZ460yy7DUMFdDWuSpBHQUp76cyLMw1BSUvmnjrZILzkLMUCb8xaHpmiMJXcwxaljnbc8V1G8L+ZgEdbf6AvtchhuxEVIQx5QymQsv3WpMbWOegXqegVUb+WomjOUqEkLoE1kThAYceFdJvr0wiadHYx8HS5C7r/Bcm/tfk7vMZVfnPzrG9KWjt5HWkgPvlga2ZUQOcRMhdN4s/QtXb/qCsqVlPBvZFgF5BdeM7PisKPptVAGsmmPp3xT+zn13NTwI4R1y2QWV2tLxi01gLRbeGetXlg5zppxRDeb8WYsmTuVRwi+2JYCkwYQEuWElygNotCXRm6i6Lv47FBosSAFsNWsXE2JbmXDxj144oiGWsnbHeq/zGVeqtINog5zOGj7oFlVq+LZWsXLSrdH42gjkQ== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000012, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 1/20/25 6:22 AM, Leon Romanovsky wrote: > On Fri, Jan 17, 2025 at 09:16:52PM +0000, David Howells wrote: >> Hi, >> >> I'd like to propose a discussion of two things: firstly, how might we improve >> iov_iter and, secondly, would it be possible to replace scatterlists. > > <...> > >> Rumour has it that John Hubbard may be working along similar lines, possibly >> just in the area of bio_vecs and ITER_BVEC. I do feel the need to apologize to Leon here, because I've been mostly MIA ever we talked about this at LPC. Perhaps I'll actually be of some use in 2025. :) >> >> >> [*] Second: Can we replace the uses of scatterlist with iov_iter and reduce >> the number of iterator classes we have? > > <...> > > I would say yes to the questions. > > Regarding rumors, I don't know, but Christoph, Jason and I are working towards > this goal. We proposed new DMA API which doesn't need scatterlists and allows > callers to implement their own data-structures. > > See this "[PATCH v6 00/17] Provide a new two step DMA mapping API" series > https://lore.kernel.org/all/cover.1737106761.git.leon@kernel.org > and its block layer followup "[RFC PATCH 0/7] Block and NMMe PCI use of > new DMA mapping API" > https://lore.kernel.org/all/cover.1730037261.git.leon@kernel.org > > Thanks thanks, -- John Hubbard