We only need the special pud_entry walker if PUD-sized hugepages and pte mappings are supported, else the common pagewalk code will take care of the iteration. Not implementing this callback reduced the amount of code compiled for non-x86 platforms, and also fixes compile failures with other architectures when helpers like pud_pfn are not implemented. Signed-off-by: Christoph Hellwig <hch@xxxxxx> Reviewed-by: Jason Gunthorpe <jgg@xxxxxxxxxxxx> --- mm/hmm.c | 29 ++++++++++++++++------------- 1 file changed, 16 insertions(+), 13 deletions(-) diff --git a/mm/hmm.c b/mm/hmm.c index 2083e4db46f5..5e7afe685213 100644 --- a/mm/hmm.c +++ b/mm/hmm.c @@ -455,15 +455,6 @@ static inline uint64_t pmd_to_hmm_pfn_flags(struct hmm_range *range, pmd_t pmd) range->flags[HMM_PFN_VALID]; } -static inline uint64_t pud_to_hmm_pfn_flags(struct hmm_range *range, pud_t pud) -{ - if (!pud_present(pud)) - return 0; - return pud_write(pud) ? range->flags[HMM_PFN_VALID] | - range->flags[HMM_PFN_WRITE] : - range->flags[HMM_PFN_VALID]; -} - static int hmm_vma_handle_pmd(struct mm_walk *walk, unsigned long addr, unsigned long end, @@ -700,10 +691,19 @@ static int hmm_vma_walk_pmd(pmd_t *pmdp, return 0; } -static int hmm_vma_walk_pud(pud_t *pudp, - unsigned long start, - unsigned long end, - struct mm_walk *walk) +#if defined(CONFIG_ARCH_HAS_PTE_DEVMAP) && \ + defined(CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD) +static inline uint64_t pud_to_hmm_pfn_flags(struct hmm_range *range, pud_t pud) +{ + if (!pud_present(pud)) + return 0; + return pud_write(pud) ? range->flags[HMM_PFN_VALID] | + range->flags[HMM_PFN_WRITE] : + range->flags[HMM_PFN_VALID]; +} + +static int hmm_vma_walk_pud(pud_t *pudp, unsigned long start, unsigned long end, + struct mm_walk *walk) { struct hmm_vma_walk *hmm_vma_walk = walk->private; struct hmm_range *range = hmm_vma_walk->range; @@ -765,6 +765,9 @@ static int hmm_vma_walk_pud(pud_t *pudp, return 0; } +#else +#define hmm_vma_walk_pud NULL +#endif static int hmm_vma_walk_hugetlb_entry(pte_t *pte, unsigned long hmask, unsigned long start, unsigned long end, -- 2.20.1