diff options
Diffstat (limited to 'mm/memory.c')
-rw-r--r-- | mm/memory.c | 36 |
1 files changed, 2 insertions, 34 deletions
diff --git a/mm/memory.c b/mm/memory.c index bcd29104f5ea..652370703e41 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -5884,8 +5884,8 @@ int __pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long address) * Only IO mappings and raw PFN mappings are allowed. The mmap semaphore * should be taken for read. * - * KVM uses this function. While it is arguably less bad than ``follow_pfn``, - * it is not a good general-purpose API. + * KVM uses this function. While it is arguably less bad than the historic + * ``follow_pfn``, it is not a good general-purpose API. * * Return: zero on success, -ve otherwise. */ @@ -5927,38 +5927,6 @@ out: } EXPORT_SYMBOL_GPL(follow_pte); -/** - * follow_pfn - look up PFN at a user virtual address - * @vma: memory mapping - * @address: user virtual address - * @pfn: location to store found PFN - * - * Only IO mappings and raw PFN mappings are allowed. - * - * This function does not allow the caller to read the permissions - * of the PTE. Do not use it. - * - * Return: zero and the pfn at @pfn on success, -ve otherwise. - */ -int follow_pfn(struct vm_area_struct *vma, unsigned long address, - unsigned long *pfn) -{ - int ret = -EINVAL; - spinlock_t *ptl; - pte_t *ptep; - - if (!(vma->vm_flags & (VM_IO | VM_PFNMAP))) - return ret; - - ret = follow_pte(vma->vm_mm, address, &ptep, &ptl); - if (ret) - return ret; - *pfn = pte_pfn(ptep_get(ptep)); - pte_unmap_unlock(ptep, ptl); - return 0; -} -EXPORT_SYMBOL(follow_pfn); - #ifdef CONFIG_HAVE_IOREMAP_PROT int follow_phys(struct vm_area_struct *vma, unsigned long address, unsigned int flags, |