diff options
| author | Benjamin Herrenschmidt <benh@kernel.crashing.org> | 2008-07-23 21:27:08 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2008-07-24 10:47:15 -0700 |
| commit | a1f242ff460e4b50a045fa237c3c56cce9eabf83 (patch) | |
| tree | 657766b55251042b38967422dc9c3ea893b98747 /arch/powerpc/mm/pgtable_32.c | |
| parent | 7ae8ed5053a39082d224a3f48409e016baca9c16 (diff) | |
powerpc ioremap_prot
This adds ioremap_prot and pte_pgprot() so that one can extract protection
bits from a PTE and use them to ioremap_prot() (in order to support ptrace
of VM_IO | VM_PFNMAP as per Rik's patch).
This moves a couple of flag checks around in the ioremap implementations
of arch/powerpc. There's a side effect of allowing non-cacheable and
non-guarded mappings on ppc32 which before would always have _PAGE_GUARDED
set whenever _PAGE_NO_CACHE is.
(standard ioremap will still set _PAGE_GUARDED, but ioremap_prot will be
capable of setting such a non guarded mapping).
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Rik van Riel <riel@redhat.com>
Cc: Dave Airlie <airlied@linux.ie>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'arch/powerpc/mm/pgtable_32.c')
| -rw-r--r-- | arch/powerpc/mm/pgtable_32.c | 22 |
1 files changed, 16 insertions, 6 deletions
diff --git a/arch/powerpc/mm/pgtable_32.c b/arch/powerpc/mm/pgtable_32.c index c7584072dfc..2001abdb191 100644 --- a/arch/powerpc/mm/pgtable_32.c +++ b/arch/powerpc/mm/pgtable_32.c @@ -145,13 +145,20 @@ void pte_free(struct mm_struct *mm, pgtable_t ptepage) void __iomem * ioremap(phys_addr_t addr, unsigned long size) { - return __ioremap(addr, size, _PAGE_NO_CACHE); + return __ioremap(addr, size, _PAGE_NO_CACHE | _PAGE_GUARDED); } EXPORT_SYMBOL(ioremap); void __iomem * ioremap_flags(phys_addr_t addr, unsigned long size, unsigned long flags) { + /* writeable implies dirty for kernel addresses */ + if (flags & _PAGE_RW) + flags |= _PAGE_DIRTY | _PAGE_HWWRITE; + + /* we don't want to let _PAGE_USER and _PAGE_EXEC leak out */ + flags &= ~(_PAGE_USER | _PAGE_EXEC | _PAGE_HWEXEC); + return __ioremap(addr, size, flags); } EXPORT_SYMBOL(ioremap_flags); @@ -163,6 +170,14 @@ __ioremap(phys_addr_t addr, unsigned long size, unsigned long flags) phys_addr_t p; int err; + /* Make sure we have the base flags */ + if ((flags & _PAGE_PRESENT) == 0) + flags |= _PAGE_KERNEL; + + /* Non-cacheable page cannot be coherent */ + if (flags & _PAGE_NO_CACHE) + flags &= ~_PAGE_COHERENT; + /* * Choose an address to map it to. * Once the vmalloc system is running, we use it. @@ -219,11 +234,6 @@ __ioremap(phys_addr_t addr, unsigned long size, unsigned long flags) v = (ioremap_bot -= size); } - if ((flags & _PAGE_PRESENT) == 0) - flags |= _PAGE_KERNEL; - if (flags & _PAGE_NO_CACHE) - flags |= _PAGE_GUARDED; - /* * Should check if it is a candidate for a BAT mapping */ |