Messages in this thread | | | Date | Mon, 26 Jul 1999 19:48:10 -0400 (EDT) | From | Benjamin LaHaise <> | Subject | Re: addresses & kernel modules for PCI drivers |
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On Mon, 26 Jul 1999, Michael Berg wrote:
> The problem is that any memory I allocate for this buffer in the module > is a 32-bit address well above the range of addresses that will fit into > the high 14 bits that I have available. > > Is there a way for the module to obtain a 256KByte chunk of memory that > can be addresses with only 14 bits?
Yeap. __get_free_pages always returns objects aligned to their own size. So just do
addr = __get_free_pages(GFP_KERNEL, 18 - PAGE_SHIFT); /*256KB*/
to get the memory you need. One other thing to consider is that since it is a large contiguous chunk of memory, you should probably allocate it at load time in order to avoid things like open() failing sporadically.
-ben
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