diff options
| author | Daniel Vetter <daniel.vetter@ffwll.ch> | 2017-02-01 09:06:26 +0100 |
|---|---|---|
| committer | Daniel Vetter <daniel.vetter@ffwll.ch> | 2017-02-01 09:06:26 +0100 |
| commit | 45bf86e7731606a475b7f989486de23b0784bfe7 (patch) | |
| tree | dac8a776783d6322bedf346060fb6000251c8b40 /mm/memory.c | |
| parent | 059c7a5a748d4e7481d8b1b4cf0e182cb81496ad (diff) | |
| parent | 18566acac18f5784347bc5fe636a26897d1c963b (diff) | |
Merge remote-tracking branch 'airlied/drm-next' into drm-misc-next
Backmerge to resync and also so that Ville can apply a cleanup patch
from Takashi.
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Diffstat (limited to 'mm/memory.c')
| -rw-r--r-- | mm/memory.c | 41 |
1 files changed, 32 insertions, 9 deletions
diff --git a/mm/memory.c b/mm/memory.c index 9f2c15cdb32c..6bf2b471e30c 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -3772,8 +3772,8 @@ int __pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long address) } #endif /* __PAGETABLE_PMD_FOLDED */ -static int __follow_pte(struct mm_struct *mm, unsigned long address, - pte_t **ptepp, spinlock_t **ptlp) +static int __follow_pte_pmd(struct mm_struct *mm, unsigned long address, + pte_t **ptepp, pmd_t **pmdpp, spinlock_t **ptlp) { pgd_t *pgd; pud_t *pud; @@ -3790,11 +3790,20 @@ static int __follow_pte(struct mm_struct *mm, unsigned long address, pmd = pmd_offset(pud, address); VM_BUG_ON(pmd_trans_huge(*pmd)); - if (pmd_none(*pmd) || unlikely(pmd_bad(*pmd))) - goto out; - /* We cannot handle huge page PFN maps. Luckily they don't exist. */ - if (pmd_huge(*pmd)) + if (pmd_huge(*pmd)) { + if (!pmdpp) + goto out; + + *ptlp = pmd_lock(mm, pmd); + if (pmd_huge(*pmd)) { + *pmdpp = pmd; + return 0; + } + spin_unlock(*ptlp); + } + + if (pmd_none(*pmd) || unlikely(pmd_bad(*pmd))) goto out; ptep = pte_offset_map_lock(mm, pmd, address, ptlp); @@ -3810,16 +3819,30 @@ out: return -EINVAL; } -int follow_pte(struct mm_struct *mm, unsigned long address, pte_t **ptepp, - spinlock_t **ptlp) +static inline int follow_pte(struct mm_struct *mm, unsigned long address, + pte_t **ptepp, spinlock_t **ptlp) +{ + int res; + + /* (void) is needed to make gcc happy */ + (void) __cond_lock(*ptlp, + !(res = __follow_pte_pmd(mm, address, ptepp, NULL, + ptlp))); + return res; +} + +int follow_pte_pmd(struct mm_struct *mm, unsigned long address, + pte_t **ptepp, pmd_t **pmdpp, spinlock_t **ptlp) { int res; /* (void) is needed to make gcc happy */ (void) __cond_lock(*ptlp, - !(res = __follow_pte(mm, address, ptepp, ptlp))); + !(res = __follow_pte_pmd(mm, address, ptepp, pmdpp, + ptlp))); return res; } +EXPORT_SYMBOL(follow_pte_pmd); /** * follow_pfn - look up PFN at a user virtual address |