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| author | Liam R. Howlett <Liam.Howlett@Oracle.com> | 2020-10-17 16:14:06 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2020-10-18 09:27:09 -0700 |
| commit | 3903b55a6117ee5a8c90108beaf8d921474aa05a (patch) | |
| tree | 4bdc04d5999b35923f276000b8abb60cd919599b /mm | |
| parent | 4dc200cee1950ac3f9b99f0c8d4a750b62958f81 (diff) | |
| download | lwn-3903b55a6117ee5a8c90108beaf8d921474aa05a.tar.gz lwn-3903b55a6117ee5a8c90108beaf8d921474aa05a.zip | |
mm/mmap: add inline vma_next() for readability of mmap code
There are three places that the next vma is required which uses the same
block of code. Replace the block with a function and add comments on what
happens in the case where NULL is encountered.
Signed-off-by: Liam R. Howlett <Liam.Howlett@Oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20200818154707.2515169-1-Liam.Howlett@Oracle.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm')
| -rw-r--r-- | mm/mmap.c | 26 |
1 files changed, 20 insertions, 6 deletions
diff --git a/mm/mmap.c b/mm/mmap.c index ebb92f5515a1..b0b8e9e94220 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -558,6 +558,23 @@ static int find_vma_links(struct mm_struct *mm, unsigned long addr, return 0; } +/* + * vma_next() - Get the next VMA. + * @mm: The mm_struct. + * @vma: The current vma. + * + * If @vma is NULL, return the first vma in the mm. + * + * Returns: The next VMA after @vma. + */ +static inline struct vm_area_struct *vma_next(struct mm_struct *mm, + struct vm_area_struct *vma) +{ + if (!vma) + return mm->mmap; + + return vma->vm_next; +} static unsigned long count_vma_pages_range(struct mm_struct *mm, unsigned long addr, unsigned long end) { @@ -1128,10 +1145,7 @@ struct vm_area_struct *vma_merge(struct mm_struct *mm, if (vm_flags & VM_SPECIAL) return NULL; - if (prev) - next = prev->vm_next; - else - next = mm->mmap; + next = vma_next(mm, prev); area = next; if (area && area->vm_end == end) /* cases 6, 7, 8 */ next = next->vm_next; @@ -2632,7 +2646,7 @@ static void unmap_region(struct mm_struct *mm, struct vm_area_struct *vma, struct vm_area_struct *prev, unsigned long start, unsigned long end) { - struct vm_area_struct *next = prev ? prev->vm_next : mm->mmap; + struct vm_area_struct *next = vma_next(mm, prev); struct mmu_gather tlb; lru_add_drain(); @@ -2831,7 +2845,7 @@ int __do_munmap(struct mm_struct *mm, unsigned long start, size_t len, if (error) return error; } - vma = prev ? prev->vm_next : mm->mmap; + vma = vma_next(mm, prev); if (unlikely(uf)) { /* |