diff options
Diffstat (limited to 'mm')
| -rw-r--r-- | mm/mmap.c | 29 | ||||
| -rw-r--r-- | mm/nommu.c | 11 |
2 files changed, 40 insertions, 0 deletions
diff --git a/mm/mmap.c b/mm/mmap.c index 0baa2ca5b0bf..699af34c3573 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -2062,6 +2062,35 @@ get_unmapped_area(struct file *file, unsigned long addr, unsigned long len, EXPORT_SYMBOL(get_unmapped_area); /** + * find_vma_intersection() - Look up the first VMA which intersects the interval + * @mm: The process address space. + * @start_addr: The inclusive start user address. + * @end_addr: The exclusive end user address. + * + * Returns: The first VMA within the provided range, %NULL otherwise. Assumes + * start_addr < end_addr. + */ +struct vm_area_struct *find_vma_intersection(struct mm_struct *mm, + unsigned long start_addr, + unsigned long end_addr) +{ + struct vm_area_struct *vma; + unsigned long index = start_addr; + + mmap_assert_locked(mm); + /* Check the cache first. */ + vma = vmacache_find(mm, start_addr); + if (likely(vma)) + return vma; + + vma = mt_find(&mm->mm_mt, &index, end_addr - 1); + if (vma) + vmacache_update(start_addr, vma); + return vma; +} +EXPORT_SYMBOL(find_vma_intersection); + +/** * find_vma() - Find the VMA for a given address, or the next VMA. * @mm: The mm_struct to check * @addr: The address diff --git a/mm/nommu.c b/mm/nommu.c index 321c7e6718a8..2702790d05d3 100644 --- a/mm/nommu.c +++ b/mm/nommu.c @@ -642,6 +642,17 @@ static void delete_vma(struct mm_struct *mm, struct vm_area_struct *vma) vm_area_free(vma); } +struct vm_area_struct *find_vma_intersection(struct mm_struct *mm, + unsigned long start_addr, + unsigned long end_addr) +{ + unsigned long index = start_addr; + + mmap_assert_locked(mm); + return mt_find(&mm->mm_mt, &index, end_addr - 1); +} +EXPORT_SYMBOL(find_vma_intersection); + /* * look up the first VMA in which addr resides, NULL if none * - should be called with mm->mmap_lock at least held readlocked |