mm/hmm: cleanup the hmm_vma_handle_pmd stub

Stub out the whole function when CONFIG_TRANSPARENT_HUGEPAGE is not set to
make the function easier to read.

Link: https://lore.kernel.org/r/20190806160554.14046-12-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

diff --git a/mm/hmm.c b/mm/hmm.c
index fb13064..900cb48 100644 (file)
--- a/mm/hmm.c
+++ b/mm/hmm.c
@@ -456,13 +456,10 @@ static inline uint64_t pmd_to_hmm_pfn_flags(struct hmm_range *range, pmd_t pmd)
                                range->flags[HMM_PFN_VALID];
 }
 
-static int hmm_vma_handle_pmd(struct mm_walk *walk,
-                             unsigned long addr,
-                             unsigned long end,
-                             uint64_t *pfns,
-                             pmd_t pmd)
-{
 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
+static int hmm_vma_handle_pmd(struct mm_walk *walk, unsigned long addr,
+               unsigned long end, uint64_t *pfns, pmd_t pmd)
+{
        struct hmm_vma_walk *hmm_vma_walk = walk->private;
        struct hmm_range *range = hmm_vma_walk->range;
        unsigned long pfn, npages, i;
@@ -493,11 +490,12 @@ static int hmm_vma_handle_pmd(struct mm_walk *walk,
        }
        hmm_vma_walk->last = end;
        return 0;
-#else
-       /* If THP is not enabled then we should never reach this code ! */
-       return -EINVAL;
-#endif
 }
+#else /* CONFIG_TRANSPARENT_HUGEPAGE */
+/* stub to allow the code below to compile */
+int hmm_vma_handle_pmd(struct mm_walk *walk, unsigned long addr,
+               unsigned long end, uint64_t *pfns, pmd_t pmd);
+#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
 
 static inline uint64_t pte_to_hmm_pfn_flags(struct hmm_range *range, pte_t pte)
 {