sh: Handle shm_align_mask also for HAVE_ARCH_UNMAPPED_AREA_TOPDOWN.
Presently shm_align_mask is only looked at for the bottom up case, but we
still want this for proper colouring constraints in the topdown case.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
diff --git a/arch/sh/include/asm/cacheflush.h b/arch/sh/include/asm/cacheflush.h
index 09acbc3..4c5462d 100644
--- a/arch/sh/include/asm/cacheflush.h
+++ b/arch/sh/include/asm/cacheflush.h
@@ -75,7 +75,5 @@
#define flush_cache_vmap(start, end) flush_cache_all()
#define flush_cache_vunmap(start, end) flush_cache_all()
-#define HAVE_ARCH_UNMAPPED_AREA
-
#endif /* __KERNEL__ */
#endif /* __ASM_SH_CACHEFLUSH_H */
diff --git a/arch/sh/include/asm/pgtable.h b/arch/sh/include/asm/pgtable.h
index b517ae0..2a011b1 100644
--- a/arch/sh/include/asm/pgtable.h
+++ b/arch/sh/include/asm/pgtable.h
@@ -154,6 +154,10 @@
#define kmap_coherent_init() do { } while (0)
#endif
+/* arch/sh/mm/mmap.c */
+#define HAVE_ARCH_UNMAPPED_AREA
+#define HAVE_ARCH_UNMAPPED_AREA_TOPDOWN
+
#include <asm-generic/pgtable.h>
#endif /* __ASM_SH_PGTABLE_H */
diff --git a/arch/sh/mm/mmap.c b/arch/sh/mm/mmap.c
index 931f4d0..1b5fdfb 100644
--- a/arch/sh/mm/mmap.c
+++ b/arch/sh/mm/mmap.c
@@ -1,7 +1,7 @@
/*
* arch/sh/mm/mmap.c
*
- * Copyright (C) 2008 Paul Mundt
+ * Copyright (C) 2008 - 2009 Paul Mundt
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
@@ -21,9 +21,26 @@
/*
* To avoid cache aliases, we map the shared page with same color.
*/
-#define COLOUR_ALIGN(addr, pgoff) \
- ((((addr) + shm_align_mask) & ~shm_align_mask) + \
- (((pgoff) << PAGE_SHIFT) & shm_align_mask))
+static inline unsigned long COLOUR_ALIGN(unsigned long addr,
+ unsigned long pgoff)
+{
+ unsigned long base = (addr + shm_align_mask) & ~shm_align_mask;
+ unsigned long off = (pgoff << PAGE_SHIFT) & shm_align_mask;
+
+ return base + off;
+}
+
+static inline unsigned long COLOUR_ALIGN_DOWN(unsigned long addr,
+ unsigned long pgoff)
+{
+ unsigned long base = addr & ~shm_align_mask;
+ unsigned long off = (pgoff << PAGE_SHIFT) & shm_align_mask;
+
+ if (base + off <= addr)
+ return base + off;
+
+ return base - off;
+}
unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr,
unsigned long len, unsigned long pgoff, unsigned long flags)
@@ -103,6 +120,117 @@
addr = COLOUR_ALIGN(addr, pgoff);
}
}
+
+unsigned long
+arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0,
+ const unsigned long len, const unsigned long pgoff,
+ const unsigned long flags)
+{
+ struct vm_area_struct *vma;
+ struct mm_struct *mm = current->mm;
+ unsigned long addr = addr0;
+ int do_colour_align;
+
+ if (flags & MAP_FIXED) {
+ /* We do not accept a shared mapping if it would violate
+ * cache aliasing constraints.
+ */
+ if ((flags & MAP_SHARED) &&
+ ((addr - (pgoff << PAGE_SHIFT)) & shm_align_mask))
+ return -EINVAL;
+ return addr;
+ }
+
+ if (unlikely(len > TASK_SIZE))
+ return -ENOMEM;
+
+ do_colour_align = 0;
+ if (filp || (flags & MAP_SHARED))
+ do_colour_align = 1;
+
+ /* requesting a specific address */
+ if (addr) {
+ if (do_colour_align)
+ addr = COLOUR_ALIGN(addr, pgoff);
+ else
+ addr = PAGE_ALIGN(addr);
+
+ vma = find_vma(mm, addr);
+ if (TASK_SIZE - len >= addr &&
+ (!vma || addr + len <= vma->vm_start))
+ return addr;
+ }
+
+ /* check if free_area_cache is useful for us */
+ if (len <= mm->cached_hole_size) {
+ mm->cached_hole_size = 0;
+ mm->free_area_cache = mm->mmap_base;
+ }
+
+ /* either no address requested or can't fit in requested address hole */
+ addr = mm->free_area_cache;
+ if (do_colour_align) {
+ unsigned long base = COLOUR_ALIGN_DOWN(addr-len, pgoff);
+
+ addr = base + len;
+ }
+
+ /* make sure it can fit in the remaining address space */
+ if (likely(addr > len)) {
+ vma = find_vma(mm, addr-len);
+ if (!vma || addr <= vma->vm_start) {
+ /* remember the address as a hint for next time */
+ return (mm->free_area_cache = addr-len);
+ }
+ }
+
+ if (unlikely(mm->mmap_base < len))
+ goto bottomup;
+
+ addr = mm->mmap_base-len;
+ if (do_colour_align)
+ addr = COLOUR_ALIGN_DOWN(addr, pgoff);
+
+ do {
+ /*
+ * Lookup failure means no vma is above this address,
+ * else if new region fits below vma->vm_start,
+ * return with success:
+ */
+ vma = find_vma(mm, addr);
+ if (likely(!vma || addr+len <= vma->vm_start)) {
+ /* remember the address as a hint for next time */
+ return (mm->free_area_cache = addr);
+ }
+
+ /* remember the largest hole we saw so far */
+ if (addr + mm->cached_hole_size < vma->vm_start)
+ mm->cached_hole_size = vma->vm_start - addr;
+
+ /* try just below the current vma->vm_start */
+ addr = vma->vm_start-len;
+ if (do_colour_align)
+ addr = COLOUR_ALIGN_DOWN(addr, pgoff);
+ } while (likely(len < vma->vm_start));
+
+bottomup:
+ /*
+ * A failed mmap() very likely causes application failure,
+ * so fall back to the bottom-up function here. This scenario
+ * can happen with large stack limits and large mmap()
+ * allocations.
+ */
+ mm->cached_hole_size = ~0UL;
+ mm->free_area_cache = TASK_UNMAPPED_BASE;
+ addr = arch_get_unmapped_area(filp, addr0, len, pgoff, flags);
+ /*
+ * Restore the topdown base:
+ */
+ mm->free_area_cache = mm->mmap_base;
+ mm->cached_hole_size = ~0UL;
+
+ return addr;
+}
#endif /* CONFIG_MMU */
/*