• Ingo Molnar's avatar
    x86/boot/e820: Move the memblock_find_dma_reserve() function and rename it to... · 4270fd8b
    Ingo Molnar authored
    x86/boot/e820: Move the memblock_find_dma_reserve() function and rename it to memblock_set_dma_reserve()
    
    We introduced memblock_find_dma_reserve() in this commit:
    
       6f2a7536 x86, memblock: Use memblock_memory_size()/memblock_free_memory_size() to get correct dma_reserve
    
    But there's several problems with it:
    
     - The changelog is full of typos and is incomprehensible in general, and
       the comments in the code are not much better either.
    
     - The function was inexplicably placed into e820.c, while it has very
       little connection to the E820 table: when we call
       memblock_find_dma_reserve() then memblock is already set up and we
       are not using the E820 table anymore.
    
     - The function is a wrapper around set_dma_reserve(), but changed the 'set'
       name to 'find' - actively misleading about its primary purpose, which is
       still to set the DMA-reserve value.
    
     - The function is limited to 64-bit systems, but neither the changelog nor
       the comments explain why. The change would appear to be relevant to
       32-bit systems as well, as the ISA DMA zone is the first 16 MB of RAM.
    
    So address some of these problems:
    
     - Move it into arch/x86/mm/init.c, next to the other zone setup related
       functions.
    
     - Clean up the code flow and names of local variables a bit.
    
     - Rename it to memblock_set_dma_reserve()
    
     - Improve the comments.
    
    No change in functionality. Enabling it for 32-bit systems is left
    for a separate patch.
    
    Cc: Alex Thorlton <athorlton@sgi.com>
    Cc: Andy Lutomirski <luto@kernel.org>
    Cc: Borislav Petkov <bp@alien8.de>
    Cc: Brian Gerst <brgerst@gmail.com>
    Cc: Dan Williams <dan.j.williams@intel.com>
    Cc: Denys Vlasenko <dvlasenk@redhat.com>
    Cc: H. Peter Anvin <hpa@zytor.com>
    Cc: Huang, Ying <ying.huang@intel.com>
    Cc: Josh Poimboeuf <jpoimboe@redhat.com>
    Cc: Juergen Gross <jgross@suse.com>
    Cc: Linus Torvalds <torvalds@linux-foundation.org>
    Cc: Paul Jackson <pj@sgi.com>
    Cc: Peter Zijlstra <peterz@infradead.org>
    Cc: Rafael J. Wysocki <rjw@sisk.pl>
    Cc: Tejun Heo <tj@kernel.org>
    Cc: Thomas Gleixner <tglx@linutronix.de>
    Cc: Wei Yang <richard.weiyang@gmail.com>
    Cc: Yinghai Lu <yinghai@kernel.org>
    Cc: linux-kernel@vger.kernel.org
    Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
    4270fd8b
pgtable.h 23.3 KB