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path: root/include/asm-powerpc/pgtable-64k.h
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2007-05-09[POWERPC] Add ability to 4K kernel to hash in 64K pagesBenjamin Herrenschmidt
This adds the ability for a kernel compiled with 4K page size to have special slices containing 64K pages and hash the right type of hash PTEs. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-05-02[POWERPC] Remove arch/powerpc's dependence on asm-ppc/pg{alloc,table}.hDavid Gibson
Currently, all 32-bit powerpc platforms use asm-ppc/pgtable.h and asm-ppc/pgalloc.h, even when otherwise compiled with ARCH=powerpc. Those asm-ppc files are a fairly nasty tangle of #ifdefs including a bunch of things which shouldn't be necessary any more in arch/powerpc. Cleaning up that mess is going to take a while, but this patch is a first step. It separates the asm-powerpc/pg{alloc,table}.h into 64 bit and 32 bit versions in asm-powerpc, which the basic .h files in asm-powerpc select based on config. We make a few tiny tweaks to the innards of the files along the way, making the outermost ifdefs (double-inclusion protection and __KERNEL__) a little cleaner, and #including asm-generic/pgtable.h from the top-level asm-powerpc/pgtable.h (since both the old 32-bit and 64-bit versions ended with such an #include). Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-04-13[POWERPC] Allow drivers to map individual 4k pages to userspacePaul Mackerras
Some drivers have resources that they want to be able to map into userspace that are 4k in size. On a kernel configured with 64k pages we currently end up mapping the 4k we want plus another 60k of physical address space, which could contain anything. This can introduce security problems, for example in the case of an infiniband adaptor where the other 60k could contain registers that some other program is using for its communications. This patch adds a new function, remap_4k_pfn, which drivers can use to map a single 4k page to userspace regardless of whether the kernel is using a 4k or a 64k page size. Like remap_pfn_range, it would typically be called in a driver's mmap function. It only maps a single 4k page, which on a 64k page kernel appears replicated 16 times throughout a 64k page. On a 4k page kernel it reduces to a call to remap_pfn_range. The way this works on a 64k kernel is that a new bit, _PAGE_4K_PFN, gets set on the linux PTE. This alters the way that __hash_page_4K computes the real address to put in the HPTE. The RPN field of the linux PTE becomes the 4k RPN directly rather than being interpreted as a 64k RPN. Since the RPN field is 32 bits, this means that physical addresses being mapped with remap_4k_pfn have to be below 2^44, i.e. 0x100000000000. The patch also factors out the code in arch/powerpc/mm/hash_utils_64.c that deals with demoting a process to use 4k pages into one function that gets called in the various different places where we need to do that. There were some discrepancies between exactly what was done in the various places, such as a call to spu_flush_all_slbs in one case but not in others. Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-06-15powerpc: Use 64k pages without needing cache-inhibited large pagesPaul Mackerras
Some POWER5+ machines can do 64k hardware pages for normal memory but not for cache-inhibited pages. This patch lets us use 64k hardware pages for most user processes on such machines (assuming the kernel has been configured with CONFIG_PPC_64K_PAGES=y). User processes start out using 64k pages and get switched to 4k pages if they use any non-cacheable mappings. With this, we use 64k pages for the vmalloc region and 4k pages for the imalloc region. If anything creates a non-cacheable mapping in the vmalloc region, the vmalloc region will get switched to 4k pages. I don't know of any driver other than the DRM that would do this, though, and these machines don't have AGP. When a region gets switched from 64k pages to 4k pages, we do not have to clear out all the 64k HPTEs from the hash table immediately. We use the _PAGE_COMBO bit in the Linux PTE to indicate whether the page was hashed in as a 64k page or a set of 4k pages. If hash_page is trying to insert a 4k page for a Linux PTE and it sees that it has already been inserted as a 64k page, it first invalidates the 64k HPTE before inserting the 4k HPTE. The hash invalidation routines also use the _PAGE_COMBO bit, to determine whether to look for a 64k HPTE or a set of 4k HPTEs to remove. With those two changes, we can tolerate a mix of 4k and 64k HPTEs in the hash table, and they will all get removed when the address space is torn down. Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-01-09[PATCH] powerpc: sanitize header files for user space includesArnd Bergmann
include/asm-ppc/ had #ifdef __KERNEL__ in all header files that are not meant for use by user space, include/asm-powerpc does not have this yet. This patch gets us a lot closer there. There are a few cases where I was not sure, so I left them out. I have verified that no CONFIG_* symbols are used outside of __KERNEL__ any more and that there are no obvious compile errors when including any of the headers in user space libraries. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-11-19powerpc: Trivially merge several headers from asm-ppc64 to asm-powerpcPaul Mackerras
For these, I have just done the lame-o merge where the file ends up looking like: #ifndef CONFIG_PPC64 #include <asm-ppc/foo.h> #else ... contents from asm-ppc64/foo.h #endif so nothing has changed, really, except that we reduce include/asm-ppc64 a bit more. Signed-off-by: Paul Mackerras <paulus@samba.org>