diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2008-12-28 11:39:19 -0800 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2008-12-28 11:39:19 -0800 |
commit | 81d6e59dabb1ae0c782e9eb7e3d88f699d25b314 (patch) | |
tree | 532afd14c119f1c95206ef0d23db9c4c26a0aa34 /arch/sh/mm/mmap.c | |
parent | 4a6908a3a050aacc9c3a2f36b276b46c0629ad91 (diff) | |
parent | 59de580af1c2fd671b0cb27c41ff958859ae5288 (diff) |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6: (132 commits)
sh: oprofile: Fix up the module build.
sh: add UIO support for JPU on SH7722.
serial: sh-sci: Fix up port pinmux for SH7366.
sh: mach-rsk: Use uImage generation by default for rsk7201/7203.
sh: mach-sh03: Fix up pata_platform build breakage.
sh: enable deferred io LCDC on Migo-R
video: sh_mobile_lcdcfb deferred io support
video: deferred io with physically contiguous memory
video: deferred io cleanup
video: fix deferred io fsync()
sh: add LCDC interrupt configuration to AP325 and Migo-R
sh_mobile_lcdc: use FB_SYS helpers instead of FB_CFB
sh: split coherent pages
sh: dma: Kill off ISA DMA wrapper.
sh: Conditionalize the code dumper on CONFIG_DUMP_CODE.
sh: Kill off the unused SH_ALPHANUMERIC debug option.
sh: Enable skipping of bss on debug platforms for sh32 also.
doc: Update sh cpufreq documentation.
sh: mrshpc_setup_windows() needs to be inline.
serial: sh-sci: sci_poll_get_char() is only used by CONFIG_CONSOLE_POLL.
...
Diffstat (limited to 'arch/sh/mm/mmap.c')
-rw-r--r-- | arch/sh/mm/mmap.c | 94 |
1 files changed, 94 insertions, 0 deletions
diff --git a/arch/sh/mm/mmap.c b/arch/sh/mm/mmap.c index 8837d511710..931f4d003fa 100644 --- a/arch/sh/mm/mmap.c +++ b/arch/sh/mm/mmap.c @@ -9,7 +9,101 @@ */ #include <linux/io.h> #include <linux/mm.h> +#include <linux/mman.h> +#include <linux/module.h> #include <asm/page.h> +#include <asm/processor.h> + +#ifdef CONFIG_MMU +unsigned long shm_align_mask = PAGE_SIZE - 1; /* Sane caches */ +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)) + +unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, + unsigned long len, unsigned long pgoff, unsigned long flags) +{ + struct mm_struct *mm = current->mm; + struct vm_area_struct *vma; + unsigned long start_addr; + 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 & 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; + + 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; + } + + if (len > mm->cached_hole_size) { + start_addr = addr = mm->free_area_cache; + } else { + mm->cached_hole_size = 0; + start_addr = addr = TASK_UNMAPPED_BASE; + } + +full_search: + if (do_colour_align) + addr = COLOUR_ALIGN(addr, pgoff); + else + addr = PAGE_ALIGN(mm->free_area_cache); + + for (vma = find_vma(mm, addr); ; vma = vma->vm_next) { + /* At this point: (!vma || addr < vma->vm_end). */ + if (unlikely(TASK_SIZE - len < addr)) { + /* + * Start a new search - just in case we missed + * some holes. + */ + if (start_addr != TASK_UNMAPPED_BASE) { + start_addr = addr = TASK_UNMAPPED_BASE; + mm->cached_hole_size = 0; + goto full_search; + } + return -ENOMEM; + } + if (likely(!vma || addr + len <= vma->vm_start)) { + /* + * Remember the place where we stopped the search: + */ + mm->free_area_cache = addr + len; + return addr; + } + if (addr + mm->cached_hole_size < vma->vm_start) + mm->cached_hole_size = vma->vm_start - addr; + + addr = vma->vm_end; + if (do_colour_align) + addr = COLOUR_ALIGN(addr, pgoff); + } +} +#endif /* CONFIG_MMU */ /* * You really shouldn't be using read() or write() on /dev/mem. This |