diff options
author | David S. Miller <davem@davemloft.net> | 2009-06-15 03:02:23 -0700 |
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committer | David S. Miller <davem@davemloft.net> | 2009-06-15 03:02:23 -0700 |
commit | 9cbc1cb8cd46ce1f7645b9de249b2ce8460129bb (patch) | |
tree | 8d104ec2a459346b99413b0b77421ca7b9936c1a /arch/sh/mm/mmap.c | |
parent | ca44d6e60f9de26281fda203f58b570e1748c015 (diff) | |
parent | 45e3e1935e2857c54783291107d33323b3ef33c8 (diff) |
Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/torvalds/linux-2.6
Conflicts:
Documentation/feature-removal-schedule.txt
drivers/scsi/fcoe/fcoe.c
net/core/drop_monitor.c
net/core/net-traces.c
Diffstat (limited to 'arch/sh/mm/mmap.c')
-rw-r--r-- | arch/sh/mm/mmap.c | 136 |
1 files changed, 132 insertions, 4 deletions
diff --git a/arch/sh/mm/mmap.c b/arch/sh/mm/mmap.c index 931f4d003fa..1b5fdfb4e0c 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 @@ EXPORT_SYMBOL(shm_align_mask); /* * 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 @@ full_search: 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 */ /* |