hi
i am try to set aside some memory so i can do some dma
so i put this in the kernel 2.3.38 init/main.c
dma.BufferKernAdd = vmalloc( dma.BufferSize ) ;
dma.BufferPhysAdd = virt_to_phys(dma.BufferKernAdd) ;
and then filled the space with nnnnnnnnn
so i got the memory fine and then in my user program
i use mmap
( NULL , dma.BufferSize , PROT_READ | PROT_WRITE , MAP_SHARED,
/dev/mem , dma.BufferPhysAdd ) ;
this worked ok but i can not read the mem
so can some one please help me on this and also
Thank you
David <sector2@ihug.co.nz>
what if i used change_protection(....) can this let the memory be readed
from user space (i just dont know the pgprot flags)
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