Messages in this thread | | | From | "H. Peter Anvin" <> | Subject | Re: File copy system call proposal | Date | 7 Dec 2001 20:00:07 -0800 |
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Followup to: <1007782956.355.2.camel@quinn.rcn.nmt.edu> By author: Quinn Harris <quinn@nmt.edu> In newsgroup: linux.dev.kernel > > All kernel copy: > Commands like cp and install open the source and destination file using > the open sys call. The data from the source is copied to the > destination by repeatedly calling the read then write sys calls. This > process involves copying the data in the file from kernel memory space > to the user memory space and back again. Note that all this copying is > done by the kernel upon calling read or write. I would expect if this > can be moved completely into the kernel no memory copy operations would > be performed by the processor by using hardware DMA. >
mmap(source file); write(target file, mmap region);
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