diff options
| -rw-r--r-- | include/linux/mm.h | 2 | ||||
| -rw-r--r-- | mm/memory.c | 86 |
2 files changed, 62 insertions, 26 deletions
diff --git a/include/linux/mm.h b/include/linux/mm.h index ba86ddaa2bb8..bc0ad24cf8c0 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -1152,6 +1152,8 @@ int remap_pfn_range(struct vm_area_struct *, unsigned long addr, int vm_insert_page(struct vm_area_struct *, unsigned long addr, struct page *); int vm_insert_pfn(struct vm_area_struct *vma, unsigned long addr, unsigned long pfn); +int vm_insert_mixed(struct vm_area_struct *vma, unsigned long addr, + unsigned long pfn); struct page *follow_page(struct vm_area_struct *, unsigned long address, unsigned int foll_flags); diff --git a/mm/memory.c b/mm/memory.c index c5e88bcd8ec3..bbab1e37055e 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -1176,8 +1176,10 @@ pte_t *get_locked_pte(struct mm_struct *mm, unsigned long addr, * old drivers should use this, and they needed to mark their * pages reserved for the old functions anyway. */ -static int insert_page(struct mm_struct *mm, unsigned long addr, struct page *page, pgprot_t prot) +static int insert_page(struct vm_area_struct *vma, unsigned long addr, + struct page *page, pgprot_t prot) { + struct mm_struct *mm = vma->vm_mm; int retval; pte_t *pte; spinlock_t *ptl; @@ -1237,17 +1239,46 @@ out: * * The page does not need to be reserved. */ -int vm_insert_page(struct vm_area_struct *vma, unsigned long addr, struct page *page) +int vm_insert_page(struct vm_area_struct *vma, unsigned long addr, + struct page *page) { if (addr < vma->vm_start || addr >= vma->vm_end) return -EFAULT; if (!page_count(page)) return -EINVAL; vma->vm_flags |= VM_INSERTPAGE; - return insert_page(vma->vm_mm, addr, page, vma->vm_page_prot); + return insert_page(vma, addr, page, vma->vm_page_prot); } EXPORT_SYMBOL(vm_insert_page); +static int insert_pfn(struct vm_area_struct *vma, unsigned long addr, + unsigned long pfn, pgprot_t prot) +{ + struct mm_struct *mm = vma->vm_mm; + int retval; + pte_t *pte, entry; + spinlock_t *ptl; + + retval = -ENOMEM; + pte = get_locked_pte(mm, addr, &ptl); + if (!pte) + goto out; + retval = -EBUSY; + if (!pte_none(*pte)) + goto out_unlock; + + /* Ok, finally just insert the thing.. */ + entry = pte_mkspecial(pfn_pte(pfn, prot)); + set_pte_at(mm, addr, pte, entry); + update_mmu_cache(vma, addr, entry); /* XXX: why not for insert_page? */ + + retval = 0; +out_unlock: + pte_unmap_unlock(pte, ptl); +out: + return retval; +} + /** * vm_insert_pfn - insert single pfn into user vma * @vma: user vma to map to @@ -1261,13 +1292,8 @@ EXPORT_SYMBOL(vm_insert_page); * in that case the handler should return NULL. */ int vm_insert_pfn(struct vm_area_struct *vma, unsigned long addr, - unsigned long pfn) + unsigned long pfn) { - struct mm_struct *mm = vma->vm_mm; - int retval; - pte_t *pte, entry; - spinlock_t *ptl; - /* * Technically, architectures with pte_special can avoid all these * restrictions (same for remap_pfn_range). However we would like @@ -1280,27 +1306,35 @@ int vm_insert_pfn(struct vm_area_struct *vma, unsigned long addr, BUG_ON((vma->vm_flags & VM_PFNMAP) && is_cow_mapping(vma->vm_flags)); BUG_ON((vma->vm_flags & VM_MIXEDMAP) && pfn_valid(pfn)); - retval = -ENOMEM; - pte = get_locked_pte(mm, addr, &ptl); - if (!pte) - goto out; - retval = -EBUSY; - if (!pte_none(*pte)) - goto out_unlock; + if (addr < vma->vm_start || addr >= vma->vm_end) + return -EFAULT; + return insert_pfn(vma, addr, pfn, vma->vm_page_prot); +} +EXPORT_SYMBOL(vm_insert_pfn); - /* Ok, finally just insert the thing.. */ - entry = pte_mkspecial(pfn_pte(pfn, vma->vm_page_prot)); - set_pte_at(mm, addr, pte, entry); - update_mmu_cache(vma, addr, entry); +int vm_insert_mixed(struct vm_area_struct *vma, unsigned long addr, + unsigned long pfn) +{ + BUG_ON(!(vma->vm_flags & VM_MIXEDMAP)); - retval = 0; -out_unlock: - pte_unmap_unlock(pte, ptl); + if (addr < vma->vm_start || addr >= vma->vm_end) + return -EFAULT; -out: - return retval; + /* + * If we don't have pte special, then we have to use the pfn_valid() + * based VM_MIXEDMAP scheme (see vm_normal_page), and thus we *must* + * refcount the page if pfn_valid is true (hence insert_page rather + * than insert_pfn). + */ + if (!HAVE_PTE_SPECIAL && pfn_valid(pfn)) { + struct page *page; + + page = pfn_to_page(pfn); + return insert_page(vma, addr, page, vma->vm_page_prot); + } + return insert_pfn(vma, addr, pfn, vma->vm_page_prot); } -EXPORT_SYMBOL(vm_insert_pfn); +EXPORT_SYMBOL(vm_insert_mixed); /* * maps a range of physical memory into the requested pages. the old |