diff options
Diffstat (limited to 'mm/mmap.c')
| -rw-r--r-- | mm/mmap.c | 51 |
1 files changed, 27 insertions, 24 deletions
diff --git a/mm/mmap.c b/mm/mmap.c index 6f3766b5780..a7bf6a31c9f 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -451,9 +451,8 @@ static void vma_link(struct mm_struct *mm, struct vm_area_struct *vma, } /* - * Helper for vma_adjust in the split_vma insert case: - * insert vm structure into list and rbtree and anon_vma, - * but it has already been inserted into prio_tree earlier. + * Helper for vma_adjust() in the split_vma insert case: insert a vma into the + * mm's list and rbtree. It has already been inserted into the prio_tree. */ static void __insert_vm_struct(struct mm_struct *mm, struct vm_area_struct *vma) { @@ -1112,9 +1111,9 @@ SYSCALL_DEFINE6(mmap_pgoff, unsigned long, addr, unsigned long, len, * A dummy user value is used because we are not locking * memory so no accounting is necessary */ - len = ALIGN(len, huge_page_size(&default_hstate)); - file = hugetlb_file_setup(HUGETLB_ANON_FILE, len, VM_NORESERVE, - &user, HUGETLB_ANONHUGE_INODE); + file = hugetlb_file_setup(HUGETLB_ANON_FILE, addr, len, + VM_NORESERVE, &user, + HUGETLB_ANONHUGE_INODE); if (IS_ERR(file)) return PTR_ERR(file); } @@ -1439,10 +1438,8 @@ void arch_unmap_area(struct mm_struct *mm, unsigned long addr) /* * Is this a new hole at the lowest possible address? */ - if (addr >= TASK_UNMAPPED_BASE && addr < mm->free_area_cache) { + if (addr >= TASK_UNMAPPED_BASE && addr < mm->free_area_cache) mm->free_area_cache = addr; - mm->cached_hole_size = ~0UL; - } } /* @@ -1457,7 +1454,7 @@ arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0, { struct vm_area_struct *vma; struct mm_struct *mm = current->mm; - unsigned long addr = addr0; + unsigned long addr = addr0, start_addr; /* requested length too big for entire address space */ if (len > TASK_SIZE) @@ -1481,22 +1478,14 @@ arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0, mm->free_area_cache = mm->mmap_base; } +try_again: /* either no address requested or can't fit in requested address hole */ - addr = mm->free_area_cache; - - /* make sure it can fit in the remaining address space */ - if (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 (mm->mmap_base < len) - goto bottomup; + start_addr = addr = mm->free_area_cache; - addr = mm->mmap_base-len; + if (addr < len) + goto fail; + addr -= len; do { /* * Lookup failure means no vma is above this address, @@ -1516,7 +1505,21 @@ arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0, addr = vma->vm_start-len; } while (len < vma->vm_start); -bottomup: +fail: + /* + * if hint left us with no space for the requested + * mapping then try again: + * + * Note: this is different with the case of bottomup + * which does the fully line-search, but we use find_vma + * here that causes some holes skipped. + */ + if (start_addr != mm->mmap_base) { + mm->free_area_cache = mm->mmap_base; + mm->cached_hole_size = 0; + goto try_again; + } + /* * A failed mmap() very likely causes application failure, * so fall back to the bottom-up function here. This scenario |