ikwzm / udmabuf

User space mappable dma buffer device driver for Linux.
BSD 2-Clause "Simplified" License
539 stars 165 forks source link

> I ran into the same issue on an x86_64 and it was fixed by changing the dma_mask_bit module parameter like so: `insmod udmabuf.ko dma_mask_bit=64 udmabuf0=8388608` #99

Open bipingamiyv opened 1 year ago

bipingamiyv commented 1 year ago
          > I ran into the same issue on an x86_64 and it was fixed by changing the dma_mask_bit module parameter like so: `insmod udmabuf.ko dma_mask_bit=64 udmabuf0=8388608`

I tried the above command, but it fails to create size more than 4MiB. Can you suggest any other alternative?

Originally posted by @bipingamiyv in https://github.com/ikwzm/udmabuf/issues/25#issuecomment-1406385154

ikwzm commented 1 year ago

Thank you for the issue

u-dma-buf uses linux kernel's dma_alloc_coherent() to allocate a buffer. The buffer capacity that can be secured by dma_alloc_coherent() is determined by the architecture, Linux kernel version, build parameters, and boot parameters. It's difficult to answer this question because I don't know what your system looks like. I'm sorry I couldn't help you.