mm: Change return type int to vm_fault_t for fault handlers
Use new return type vm_fault_t for fault handler. For now, this is just
documenting that the function returns a VM_FAULT value rather than an
errno. Once all instances are converted, vm_fault_t will become a
distinct type.
Ref-> commit 1c8f422059ae ("mm: change return type to vm_fault_t")
The aim is to change the return type of finish_fault() and
handle_mm_fault() to vm_fault_t type. As part of that clean up return
type of all other recursively called functions have been changed to
vm_fault_t type.
The places from where handle_mm_fault() is getting invoked will be
change to vm_fault_t type but in a separate patch.
vmf_error() is the newly introduce inline function in 4.17-rc6.
[akpm@linux-foundation.org: don't shadow outer local `ret' in __do_huge_pmd_anonymous_page()]
Link: http://lkml.kernel.org/r/20180604171727.GA20279@jordon-HP-15-Notebook-PC
Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>
Reviewed-by: Matthew Wilcox <mawilcox@microsoft.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 9f1c853..3c21775 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -3501,14 +3501,15 @@ static void unmap_ref_private(struct mm_struct *mm, struct vm_area_struct *vma,
* cannot race with other handlers or page migration.
* Keep the pte_same checks anyway to make transition from the mutex easier.
*/
-static int hugetlb_cow(struct mm_struct *mm, struct vm_area_struct *vma,
+static vm_fault_t hugetlb_cow(struct mm_struct *mm, struct vm_area_struct *vma,
unsigned long address, pte_t *ptep,
struct page *pagecache_page, spinlock_t *ptl)
{
pte_t pte;
struct hstate *h = hstate_vma(vma);
struct page *old_page, *new_page;
- int ret = 0, outside_reserve = 0;
+ int outside_reserve = 0;
+ vm_fault_t ret = 0;
unsigned long mmun_start; /* For mmu_notifiers */
unsigned long mmun_end; /* For mmu_notifiers */
unsigned long haddr = address & huge_page_mask(h);
@@ -3572,8 +3573,7 @@ static int hugetlb_cow(struct mm_struct *mm, struct vm_area_struct *vma,
return 0;
}
- ret = (PTR_ERR(new_page) == -ENOMEM) ?
- VM_FAULT_OOM : VM_FAULT_SIGBUS;
+ ret = vmf_error(PTR_ERR(new_page));
goto out_release_old;
}
@@ -3676,12 +3676,13 @@ int huge_add_to_page_cache(struct page *page, struct address_space *mapping,
return 0;
}
-static int hugetlb_no_page(struct mm_struct *mm, struct vm_area_struct *vma,
- struct address_space *mapping, pgoff_t idx,
- unsigned long address, pte_t *ptep, unsigned int flags)
+static vm_fault_t hugetlb_no_page(struct mm_struct *mm,
+ struct vm_area_struct *vma,
+ struct address_space *mapping, pgoff_t idx,
+ unsigned long address, pte_t *ptep, unsigned int flags)
{
struct hstate *h = hstate_vma(vma);
- int ret = VM_FAULT_SIGBUS;
+ vm_fault_t ret = VM_FAULT_SIGBUS;
int anon_rmap = 0;
unsigned long size;
struct page *page;
@@ -3744,11 +3745,7 @@ static int hugetlb_no_page(struct mm_struct *mm, struct vm_area_struct *vma,
page = alloc_huge_page(vma, haddr, 0);
if (IS_ERR(page)) {
- ret = PTR_ERR(page);
- if (ret == -ENOMEM)
- ret = VM_FAULT_OOM;
- else
- ret = VM_FAULT_SIGBUS;
+ ret = vmf_error(PTR_ERR(page));
goto out;
}
clear_huge_page(page, address, pages_per_huge_page(h));
@@ -3872,12 +3869,12 @@ u32 hugetlb_fault_mutex_hash(struct hstate *h, struct mm_struct *mm,
}
#endif
-int hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma,
+vm_fault_t hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma,
unsigned long address, unsigned int flags)
{
pte_t *ptep, entry;
spinlock_t *ptl;
- int ret;
+ vm_fault_t ret;
u32 hash;
pgoff_t idx;
struct page *page = NULL;
@@ -4207,7 +4204,7 @@ long follow_hugetlb_page(struct mm_struct *mm, struct vm_area_struct *vma,
if (absent || is_swap_pte(huge_ptep_get(pte)) ||
((flags & FOLL_WRITE) &&
!huge_pte_write(huge_ptep_get(pte)))) {
- int ret;
+ vm_fault_t ret;
unsigned int fault_flags = 0;
if (pte)
