Messages in this thread | | | Date | Wed, 21 Feb 2001 18:12:34 +0100 | From | Christoph Baumann <> | Subject | Problem with DMA buffer (in 2.2.15) |
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Hello!
I have the following problem. A user process wants to talk to a PCI board via DMA. The first step I did was to resolv the physical addresses of the data in user space. This works fine when writing to the device. But when reading the buffer isn't allocated and the physical addresses are resolved to zero. I fixed this with initializing the buffer. My question is: Is there a faster method to get the kernel to map all the virtual addresses at once and not each by each? This would increase the performance enormously (from 33MB/s to [hopefully] 100MB/s).
Christoph
-- ********************************************************** * Christoph Baumann * * Kirchhoff-Institut für Physik - Uni Heidelberg * * Mail: baumann@kip.uni-heidelberg.de * * Phone: ++49-6221-54-4329 * **********************************************************
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