[PATCH v2] mm: Change return type int to vm_fault_t for fault handlers

From: Souptick Joarder
Date: Sat Jun 02 2018 - 16:02:09 EST

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.

Signed-off-by: Souptick Joarder <jrdr.linux@xxxxxxxxx>
---
v2: Change patch title and fixed sparse warning.

fs/userfaultfd.c | 6 +--
include/linux/huge_mm.h | 10 +++--
include/linux/hugetlb.h | 2 +-
include/linux/mm.h | 14 +++----
include/linux/oom.h | 2 +-
include/linux/swapops.h | 5 ++-
include/linux/userfaultfd_k.h | 5 ++-
kernel/memremap.c | 2 +-
mm/gup.c | 4 +-
mm/huge_memory.c | 25 ++++++------
mm/hugetlb.c | 34 ++++++++--------
mm/internal.h | 2 +-
mm/khugepaged.c | 3 +-
mm/memory.c | 90 ++++++++++++++++++++++---------------------
mm/shmem.c | 17 ++++----
15 files changed, 113 insertions(+), 108 deletions(-)

diff --git a/fs/userfaultfd.c b/fs/userfaultfd.c
index cec550c..bf60c6a 100644
--- a/fs/userfaultfd.c
+++ b/fs/userfaultfd.c
@@ -336,17 +336,15 @@ static inline bool userfaultfd_must_wait(struct userfaultfd_ctx *ctx,
* fatal_signal_pending()s, and the mmap_sem must be released before
* returning it.
*/
-int handle_userfault(struct vm_fault *vmf, unsigned long reason)
+vm_fault_t handle_userfault(struct vm_fault *vmf, unsigned long reason)
{
struct mm_struct *mm = vmf->vma->vm_mm;
struct userfaultfd_ctx *ctx;
struct userfaultfd_wait_queue uwq;
- int ret;
+ vm_fault_t ret = VM_FAULT_SIGBUS;
bool must_wait, return_to_userland;
long blocking_state;

- ret = VM_FAULT_SIGBUS;
-
/*
* We don't do userfault handling for the final child pid update.
*
diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h
index a8a1262..8c4f0a6 100644
--- a/include/linux/huge_mm.h
+++ b/include/linux/huge_mm.h
@@ -3,10 +3,11 @@
#define _LINUX_HUGE_MM_H

#include <linux/sched/coredump.h>
+#include <linux/mm_types.h>

#include <linux/fs.h> /* only for vma_is_dax() */

-extern int do_huge_pmd_anonymous_page(struct vm_fault *vmf);
+extern vm_fault_t do_huge_pmd_anonymous_page(struct vm_fault *vmf);
extern int copy_huge_pmd(struct mm_struct *dst_mm, struct mm_struct *src_mm,
pmd_t *dst_pmd, pmd_t *src_pmd, unsigned long addr,
struct vm_area_struct *vma);
@@ -23,7 +24,7 @@ static inline void huge_pud_set_accessed(struct vm_fault *vmf, pud_t orig_pud)
}
#endif

-extern int do_huge_pmd_wp_page(struct vm_fault *vmf, pmd_t orig_pmd);
+extern vm_fault_t do_huge_pmd_wp_page(struct vm_fault *vmf, pmd_t orig_pmd);
extern struct page *follow_trans_huge_pmd(struct vm_area_struct *vma,
unsigned long addr,
pmd_t *pmd,
@@ -216,7 +217,7 @@ struct page *follow_devmap_pmd(struct vm_area_struct *vma, unsigned long addr,
struct page *follow_devmap_pud(struct vm_area_struct *vma, unsigned long addr,
pud_t *pud, int flags);

-extern int do_huge_pmd_numa_page(struct vm_fault *vmf, pmd_t orig_pmd);
+extern vm_fault_t do_huge_pmd_numa_page(struct vm_fault *vmf, pmd_t orig_pmd);

extern struct page *huge_zero_page;

@@ -321,7 +322,8 @@ static inline spinlock_t *pud_trans_huge_lock(pud_t *pud,
return NULL;
}

-static inline int do_huge_pmd_numa_page(struct vm_fault *vmf, pmd_t orig_pmd)
+static inline vm_fault_t do_huge_pmd_numa_page(struct vm_fault *vmf,
+ pmd_t orig_pmd)
{
return 0;
}
diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
index 36fa6a2..c779b2f 100644
--- a/include/linux/hugetlb.h
+++ b/include/linux/hugetlb.h
@@ -105,7 +105,7 @@ void __unmap_hugepage_range(struct mmu_gather *tlb, struct vm_area_struct *vma,
int hugetlb_report_node_meminfo(int, char *);
void hugetlb_show_meminfo(void);
unsigned long hugetlb_total_pages(void);
-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);
int hugetlb_mcopy_atomic_pte(struct mm_struct *dst_mm, pte_t *dst_pte,
struct vm_area_struct *dst_vma,
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 02a616e..2971bff 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -694,10 +694,10 @@ static inline pte_t maybe_mkwrite(pte_t pte, struct vm_area_struct *vma)
return pte;
}

-int alloc_set_pte(struct vm_fault *vmf, struct mem_cgroup *memcg,
+vm_fault_t alloc_set_pte(struct vm_fault *vmf, struct mem_cgroup *memcg,
struct page *page);
-int finish_fault(struct vm_fault *vmf);
-int finish_mkwrite_fault(struct vm_fault *vmf);
+vm_fault_t finish_fault(struct vm_fault *vmf);
+vm_fault_t finish_mkwrite_fault(struct vm_fault *vmf);
#endif

/*
@@ -1343,8 +1343,8 @@ int generic_access_phys(struct vm_area_struct *vma, unsigned long addr,
int invalidate_inode_page(struct page *page);

#ifdef CONFIG_MMU
-extern int handle_mm_fault(struct vm_area_struct *vma, unsigned long address,
- unsigned int flags);
+extern vm_fault_t handle_mm_fault(struct vm_area_struct *vma,
+ unsigned long address, unsigned int flags);
extern int fixup_user_fault(struct task_struct *tsk, struct mm_struct *mm,
unsigned long address, unsigned int fault_flags,
bool *unlocked);
@@ -1353,7 +1353,7 @@ void unmap_mapping_pages(struct address_space *mapping,
void unmap_mapping_range(struct address_space *mapping,
loff_t const holebegin, loff_t const holelen, int even_cows);
#else
-static inline int handle_mm_fault(struct vm_area_struct *vma,
+static inline vm_fault_t handle_mm_fault(struct vm_area_struct *vma,
unsigned long address, unsigned int flags)
{
/* should never happen if there's no MMU */
@@ -2501,7 +2501,7 @@ static inline struct page *follow_page(struct vm_area_struct *vma,
#define FOLL_COW 0x4000 /* internal GUP flag */
#define FOLL_ANON 0x8000 /* don't do file mappings */

-static inline int vm_fault_to_errno(int vm_fault, int foll_flags)
+static inline int vm_fault_to_errno(vm_fault_t vm_fault, int foll_flags)
{
if (vm_fault & VM_FAULT_OOM)
return -ENOMEM;
diff --git a/include/linux/oom.h b/include/linux/oom.h
index 6adac11..9d30c15 100644
--- a/include/linux/oom.h
+++ b/include/linux/oom.h
@@ -88,7 +88,7 @@ static inline bool mm_is_oom_victim(struct mm_struct *mm)
*
* Return 0 when the PF is safe VM_FAULT_SIGBUS otherwise.
*/
-static inline int check_stable_address_space(struct mm_struct *mm)
+static inline vm_fault_t check_stable_address_space(struct mm_struct *mm)
{
if (unlikely(test_bit(MMF_UNSTABLE, &mm->flags)))
return VM_FAULT_SIGBUS;
diff --git a/include/linux/swapops.h b/include/linux/swapops.h
index 1d3877c..9bc8ddb 100644
--- a/include/linux/swapops.h
+++ b/include/linux/swapops.h
@@ -4,6 +4,7 @@

#include <linux/radix-tree.h>
#include <linux/bug.h>
+#include <linux/mm_types.h>

/*
* swapcache pages are stored in the swapper_space radix tree. We want to
@@ -134,7 +135,7 @@ static inline struct page *device_private_entry_to_page(swp_entry_t entry)
return pfn_to_page(swp_offset(entry));
}

-int device_private_entry_fault(struct vm_area_struct *vma,
+vm_fault_t device_private_entry_fault(struct vm_area_struct *vma,
unsigned long addr,
swp_entry_t entry,
unsigned int flags,
@@ -169,7 +170,7 @@ static inline struct page *device_private_entry_to_page(swp_entry_t entry)
return NULL;
}

-static inline int device_private_entry_fault(struct vm_area_struct *vma,
+static inline vm_fault_t device_private_entry_fault(struct vm_area_struct *vma,
unsigned long addr,
swp_entry_t entry,
unsigned int flags,
diff --git a/include/linux/userfaultfd_k.h b/include/linux/userfaultfd_k.h
index f2f3b68..1f36c80 100644
--- a/include/linux/userfaultfd_k.h
+++ b/include/linux/userfaultfd_k.h
@@ -28,7 +28,7 @@
#define UFFD_SHARED_FCNTL_FLAGS (O_CLOEXEC | O_NONBLOCK)
#define UFFD_FLAGS_SET (EFD_SHARED_FCNTL_FLAGS)

-extern int handle_userfault(struct vm_fault *vmf, unsigned long reason);
+extern vm_fault_t handle_userfault(struct vm_fault *vmf, unsigned long reason);

extern ssize_t mcopy_atomic(struct mm_struct *dst_mm, unsigned long dst_start,
unsigned long src_start, unsigned long len);
@@ -75,7 +75,8 @@ extern void userfaultfd_unmap_complete(struct mm_struct *mm,
#else /* CONFIG_USERFAULTFD */

/* mm helpers */
-static inline int handle_userfault(struct vm_fault *vmf, unsigned long reason)
+static inline vm_fault_t handle_userfault(struct vm_fault *vmf,
+ unsigned long reason)
{
return VM_FAULT_SIGBUS;
}
diff --git a/kernel/memremap.c b/kernel/memremap.c
index 895e6b7..d148d09 100644
--- a/kernel/memremap.c
+++ b/kernel/memremap.c
@@ -214,7 +214,7 @@ static unsigned long order_at(struct resource *res, unsigned long pgoff)
pgoff += 1UL << order, order = order_at((res), pgoff))

#if IS_ENABLED(CONFIG_DEVICE_PRIVATE)
-int device_private_entry_fault(struct vm_area_struct *vma,
+vm_fault_t device_private_entry_fault(struct vm_area_struct *vma,
unsigned long addr,
swp_entry_t entry,
unsigned int flags,
diff --git a/mm/gup.c b/mm/gup.c
index 541904a..e3a957e 100644
--- a/mm/gup.c
+++ b/mm/gup.c
@@ -481,7 +481,7 @@ static int faultin_page(struct task_struct *tsk, struct vm_area_struct *vma,
unsigned long address, unsigned int *flags, int *nonblocking)
{
unsigned int fault_flags = 0;
- int ret;
+ vm_fault_t ret;

/* mlock all present pages, but do not fault in new pages */
if ((*flags & (FOLL_POPULATE | FOLL_MLOCK)) == FOLL_MLOCK)
@@ -802,7 +802,7 @@ int fixup_user_fault(struct task_struct *tsk, struct mm_struct *mm,
bool *unlocked)
{
struct vm_area_struct *vma;
- int ret, major = 0;
+ vm_fault_t ret, major = 0;

if (unlocked)
fault_flags |= FAULT_FLAG_ALLOW_RETRY;
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index a3a1815..82dc477 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -544,14 +544,14 @@ unsigned long thp_get_unmapped_area(struct file *filp, unsigned long addr,
}
EXPORT_SYMBOL_GPL(thp_get_unmapped_area);

-static int __do_huge_pmd_anonymous_page(struct vm_fault *vmf, struct page *page,
- gfp_t gfp)
+static vm_fault_t __do_huge_pmd_anonymous_page(struct vm_fault *vmf,
+ struct page *page, gfp_t gfp)
{
struct vm_area_struct *vma = vmf->vma;
struct mem_cgroup *memcg;
pgtable_t pgtable;
unsigned long haddr = vmf->address & HPAGE_PMD_MASK;
- int ret = 0;
+ vm_fault_t ret = 0;

VM_BUG_ON_PAGE(!PageCompound(page), page);

@@ -587,7 +587,7 @@ static int __do_huge_pmd_anonymous_page(struct vm_fault *vmf, struct page *page,

/* Deliver the page fault to userland */
if (userfaultfd_missing(vma)) {
- int ret;
+ vm_fault_t ret;

spin_unlock(vmf->ptl);
mem_cgroup_cancel_charge(page, memcg, true);
@@ -666,7 +666,7 @@ static bool set_huge_zero_page(pgtable_t pgtable, struct mm_struct *mm,
return true;
}

-int do_huge_pmd_anonymous_page(struct vm_fault *vmf)
+vm_fault_t do_huge_pmd_anonymous_page(struct vm_fault *vmf)
{
struct vm_area_struct *vma = vmf->vma;
gfp_t gfp;
@@ -685,7 +685,7 @@ int do_huge_pmd_anonymous_page(struct vm_fault *vmf)
pgtable_t pgtable;
struct page *zero_page;
bool set;
- int ret;
+ vm_fault_t ret;
pgtable = pte_alloc_one(vma->vm_mm, haddr);
if (unlikely(!pgtable))
return VM_FAULT_OOM;
@@ -1121,15 +1121,16 @@ void huge_pmd_set_accessed(struct vm_fault *vmf, pmd_t orig_pmd)
spin_unlock(vmf->ptl);
}

-static int do_huge_pmd_wp_page_fallback(struct vm_fault *vmf, pmd_t orig_pmd,
- struct page *page)
+static vm_fault_t do_huge_pmd_wp_page_fallback(struct vm_fault *vmf,
+ pmd_t orig_pmd, struct page *page)
{
struct vm_area_struct *vma = vmf->vma;
unsigned long haddr = vmf->address & HPAGE_PMD_MASK;
struct mem_cgroup *memcg;
pgtable_t pgtable;
pmd_t _pmd;
- int ret = 0, i;
+ int i;
+ vm_fault_t ret = 0;
struct page **pages;
unsigned long mmun_start; /* For mmu_notifiers */
unsigned long mmun_end; /* For mmu_notifiers */
@@ -1239,7 +1240,7 @@ static int do_huge_pmd_wp_page_fallback(struct vm_fault *vmf, pmd_t orig_pmd,
goto out;
}

-int do_huge_pmd_wp_page(struct vm_fault *vmf, pmd_t orig_pmd)
+vm_fault_t do_huge_pmd_wp_page(struct vm_fault *vmf, pmd_t orig_pmd)
{
struct vm_area_struct *vma = vmf->vma;
struct page *page = NULL, *new_page;
@@ -1248,7 +1249,7 @@ int do_huge_pmd_wp_page(struct vm_fault *vmf, pmd_t orig_pmd)
unsigned long mmun_start; /* For mmu_notifiers */
unsigned long mmun_end; /* For mmu_notifiers */
gfp_t huge_gfp; /* for allocation and charge */
- int ret = 0;
+ vm_fault_t ret = 0;

vmf->ptl = pmd_lockptr(vma->vm_mm, vmf->pmd);
VM_BUG_ON_VMA(!vma->anon_vma, vma);
@@ -1459,7 +1460,7 @@ struct page *follow_trans_huge_pmd(struct vm_area_struct *vma,
}

/* NUMA hinting page fault entry point for trans huge pmds */
-int do_huge_pmd_numa_page(struct vm_fault *vmf, pmd_t pmd)
+vm_fault_t do_huge_pmd_numa_page(struct vm_fault *vmf, pmd_t pmd)
{
struct vm_area_struct *vma = vmf->vma;
struct anon_vma *anon_vma = NULL;
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 2186791..672e74c 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -3499,14 +3499,15 @@ 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 */

@@ -3570,9 +3571,8 @@ 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;
- goto out_release_old;
+ ret = vmf_error(PTR_ERR(new_page));
+ goto out_release_old;
}

/*
@@ -3675,13 +3675,14 @@ 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;
- int anon_rmap = 0;
+ vm_fault_t ret = VM_FAULT_SIGBUS;
+ int anon_rmap = 0, err;
unsigned long size;
struct page *page;
pte_t new_pte;
@@ -3742,11 +3743,8 @@ static int hugetlb_no_page(struct mm_struct *mm, struct vm_area_struct *vma,

page = alloc_huge_page(vma, address, 0);
if (IS_ERR(page)) {
- ret = PTR_ERR(page);
- if (ret == -ENOMEM)
- ret = VM_FAULT_OOM;
- else
- ret = VM_FAULT_SIGBUS;
+ err = PTR_ERR(page);
+ ret = vmf_error(err);
goto out;
}
clear_huge_page(page, address, pages_per_huge_page(h));
@@ -3870,12 +3868,12 @@ 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;
@@ -4206,7 +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)
diff --git a/mm/internal.h b/mm/internal.h
index 502d141..4044456 100644
--- a/mm/internal.h
+++ b/mm/internal.h
@@ -38,7 +38,7 @@

void page_writeback_init(void);

-int do_swap_page(struct vm_fault *vmf);
+vm_fault_t do_swap_page(struct vm_fault *vmf);

void free_pgtables(struct mmu_gather *tlb, struct vm_area_struct *start_vma,
unsigned long floor, unsigned long ceiling);
diff --git a/mm/khugepaged.c b/mm/khugepaged.c
index d7b2a4b..778fd40 100644
--- a/mm/khugepaged.c
+++ b/mm/khugepaged.c
@@ -880,7 +880,8 @@ static bool __collapse_huge_page_swapin(struct mm_struct *mm,
unsigned long address, pmd_t *pmd,
int referenced)
{
- int swapped_in = 0, ret = 0;
+ int swapped_in = 0;
+ vm_fault_t ret = 0;
struct vm_fault vmf = {
.vma = vma,
.address = address,
diff --git a/mm/memory.c b/mm/memory.c
index 01f5464..cee8245 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -2360,9 +2360,9 @@ static gfp_t __get_fault_gfp_mask(struct vm_area_struct *vma)
*
* We do this without the lock held, so that it can sleep if it needs to.
*/
-static int do_page_mkwrite(struct vm_fault *vmf)
+static vm_fault_t do_page_mkwrite(struct vm_fault *vmf)
{
- int ret;
+ vm_fault_t ret;
struct page *page = vmf->page;
unsigned int old_flags = vmf->flags;

@@ -2466,7 +2466,7 @@ static inline void wp_page_reuse(struct vm_fault *vmf)
* held to the old page, as well as updating the rmap.
* - In any case, unlock the PTL and drop the reference we took to the old page.
*/
-static int wp_page_copy(struct vm_fault *vmf)
+static vm_fault_t wp_page_copy(struct vm_fault *vmf)
{
struct vm_area_struct *vma = vmf->vma;
struct mm_struct *mm = vma->vm_mm;
@@ -2614,7 +2614,7 @@ static int wp_page_copy(struct vm_fault *vmf)
* The function expects the page to be locked or other protection against
* concurrent faults / writeback (such as DAX radix tree locks).
*/
-int finish_mkwrite_fault(struct vm_fault *vmf)
+vm_fault_t finish_mkwrite_fault(struct vm_fault *vmf)
{
WARN_ON_ONCE(!(vmf->vma->vm_flags & VM_SHARED));
vmf->pte = pte_offset_map_lock(vmf->vma->vm_mm, vmf->pmd, vmf->address,
@@ -2635,12 +2635,12 @@ int finish_mkwrite_fault(struct vm_fault *vmf)
* Handle write page faults for VM_MIXEDMAP or VM_PFNMAP for a VM_SHARED
* mapping
*/
-static int wp_pfn_shared(struct vm_fault *vmf)
+static vm_fault_t wp_pfn_shared(struct vm_fault *vmf)
{
struct vm_area_struct *vma = vmf->vma;

if (vma->vm_ops && vma->vm_ops->pfn_mkwrite) {
- int ret;
+ vm_fault_t ret;

pte_unmap_unlock(vmf->pte, vmf->ptl);
vmf->flags |= FAULT_FLAG_MKWRITE;
@@ -2653,7 +2653,7 @@ static int wp_pfn_shared(struct vm_fault *vmf)
return VM_FAULT_WRITE;
}

-static int wp_page_shared(struct vm_fault *vmf)
+static vm_fault_t wp_page_shared(struct vm_fault *vmf)
__releases(vmf->ptl)
{
struct vm_area_struct *vma = vmf->vma;
@@ -2661,7 +2661,7 @@ static int wp_page_shared(struct vm_fault *vmf)
get_page(vmf->page);

if (vma->vm_ops && vma->vm_ops->page_mkwrite) {
- int tmp;
+ vm_fault_t tmp;

pte_unmap_unlock(vmf->pte, vmf->ptl);
tmp = do_page_mkwrite(vmf);
@@ -2704,7 +2704,7 @@ static int wp_page_shared(struct vm_fault *vmf)
* but allow concurrent faults), with pte both mapped and locked.
* We return with mmap_sem still held, but pte unmapped and unlocked.
*/
-static int do_wp_page(struct vm_fault *vmf)
+static vm_fault_t do_wp_page(struct vm_fault *vmf)
__releases(vmf->ptl)
{
struct vm_area_struct *vma = vmf->vma;
@@ -2880,7 +2880,7 @@ void unmap_mapping_range(struct address_space *mapping,
* We return with the mmap_sem locked or unlocked in the same cases
* as does filemap_fault().
*/
-int do_swap_page(struct vm_fault *vmf)
+vm_fault_t do_swap_page(struct vm_fault *vmf)
{
struct vm_area_struct *vma = vmf->vma;
struct page *page = NULL, *swapcache;
@@ -2889,7 +2889,7 @@ int do_swap_page(struct vm_fault *vmf)
pte_t pte;
int locked;
int exclusive = 0;
- int ret = 0;
+ vm_fault_t ret = 0;

if (!pte_unmap_same(vma->vm_mm, vmf->pmd, vmf->pte, vmf->orig_pte))
goto out;
@@ -3100,12 +3100,12 @@ int do_swap_page(struct vm_fault *vmf)
* but allow concurrent faults), and pte mapped but not yet locked.
* We return with mmap_sem still held, but pte unmapped and unlocked.
*/
-static int do_anonymous_page(struct vm_fault *vmf)
+static vm_fault_t do_anonymous_page(struct vm_fault *vmf)
{
struct vm_area_struct *vma = vmf->vma;
struct mem_cgroup *memcg;
struct page *page;
- int ret = 0;
+ vm_fault_t ret = 0;
pte_t entry;

/* File mapping without ->vm_ops ? */
@@ -3214,10 +3214,10 @@ static int do_anonymous_page(struct vm_fault *vmf)
* released depending on flags and vma->vm_ops->fault() return value.
* See filemap_fault() and __lock_page_retry().
*/
-static int __do_fault(struct vm_fault *vmf)
+static vm_fault_t __do_fault(struct vm_fault *vmf)
{
struct vm_area_struct *vma = vmf->vma;
- int ret;
+ vm_fault_t ret;

ret = vma->vm_ops->fault(vmf);
if (unlikely(ret & (VM_FAULT_ERROR | VM_FAULT_NOPAGE | VM_FAULT_RETRY |
@@ -3251,7 +3251,7 @@ static int pmd_devmap_trans_unstable(pmd_t *pmd)
return pmd_devmap(*pmd) || pmd_trans_unstable(pmd);
}

-static int pte_alloc_one_map(struct vm_fault *vmf)
+static vm_fault_t pte_alloc_one_map(struct vm_fault *vmf)
{
struct vm_area_struct *vma = vmf->vma;

@@ -3327,13 +3327,14 @@ static void deposit_prealloc_pte(struct vm_fault *vmf)
vmf->prealloc_pte = NULL;
}

-static int do_set_pmd(struct vm_fault *vmf, struct page *page)
+static vm_fault_t do_set_pmd(struct vm_fault *vmf, struct page *page)
{
struct vm_area_struct *vma = vmf->vma;
bool write = vmf->flags & FAULT_FLAG_WRITE;
unsigned long haddr = vmf->address & HPAGE_PMD_MASK;
pmd_t entry;
- int i, ret;
+ int i;
+ vm_fault_t ret;

if (!transhuge_vma_suitable(vma, haddr))
return VM_FAULT_FALLBACK;
@@ -3383,7 +3384,7 @@ static int do_set_pmd(struct vm_fault *vmf, struct page *page)
return ret;
}
#else
-static int do_set_pmd(struct vm_fault *vmf, struct page *page)
+static vm_fault_t do_set_pmd(struct vm_fault *vmf, struct page *page)
{
BUILD_BUG();
return 0;
@@ -3404,13 +3405,13 @@ static int do_set_pmd(struct vm_fault *vmf, struct page *page)
* Target users are page handler itself and implementations of
* vm_ops->map_pages.
*/
-int alloc_set_pte(struct vm_fault *vmf, struct mem_cgroup *memcg,
+vm_fault_t alloc_set_pte(struct vm_fault *vmf, struct mem_cgroup *memcg,
struct page *page)
{
struct vm_area_struct *vma = vmf->vma;
bool write = vmf->flags & FAULT_FLAG_WRITE;
pte_t entry;
- int ret;
+ vm_fault_t ret;

if (pmd_none(*vmf->pmd) && PageTransCompound(page) &&
IS_ENABLED(CONFIG_TRANSPARENT_HUGE_PAGECACHE)) {
@@ -3469,10 +3470,10 @@ int alloc_set_pte(struct vm_fault *vmf, struct mem_cgroup *memcg,
* The function expects the page to be locked and on success it consumes a
* reference of a page being mapped (for the PTE which maps it).
*/
-int finish_fault(struct vm_fault *vmf)
+vm_fault_t finish_fault(struct vm_fault *vmf)
{
struct page *page;
- int ret = 0;
+ vm_fault_t ret = 0;

/* Did we COW the page? */
if ((vmf->flags & FAULT_FLAG_WRITE) &&
@@ -3558,12 +3559,13 @@ static int __init fault_around_debugfs(void)
* (and therefore to page order). This way it's easier to guarantee
* that we don't cross page table boundaries.
*/
-static int do_fault_around(struct vm_fault *vmf)
+static vm_fault_t do_fault_around(struct vm_fault *vmf)
{
unsigned long address = vmf->address, nr_pages, mask;
pgoff_t start_pgoff = vmf->pgoff;
pgoff_t end_pgoff;
- int off, ret = 0;
+ int off;
+ vm_fault_t ret = 0;

nr_pages = READ_ONCE(fault_around_bytes) >> PAGE_SHIFT;
mask = ~(nr_pages * PAGE_SIZE - 1) & PAGE_MASK;
@@ -3613,10 +3615,10 @@ static int do_fault_around(struct vm_fault *vmf)
return ret;
}

-static int do_read_fault(struct vm_fault *vmf)
+static vm_fault_t do_read_fault(struct vm_fault *vmf)
{
struct vm_area_struct *vma = vmf->vma;
- int ret = 0;
+ vm_fault_t ret = 0;

/*
* Let's call ->map_pages() first and use ->fault() as fallback
@@ -3640,10 +3642,10 @@ static int do_read_fault(struct vm_fault *vmf)
return ret;
}

-static int do_cow_fault(struct vm_fault *vmf)
+static vm_fault_t do_cow_fault(struct vm_fault *vmf)
{
struct vm_area_struct *vma = vmf->vma;
- int ret;
+ vm_fault_t ret;

if (unlikely(anon_vma_prepare(vma)))
return VM_FAULT_OOM;
@@ -3679,10 +3681,10 @@ static int do_cow_fault(struct vm_fault *vmf)
return ret;
}

-static int do_shared_fault(struct vm_fault *vmf)
+static vm_fault_t do_shared_fault(struct vm_fault *vmf)
{
struct vm_area_struct *vma = vmf->vma;
- int ret, tmp;
+ vm_fault_t ret, tmp;

ret = __do_fault(vmf);
if (unlikely(ret & (VM_FAULT_ERROR | VM_FAULT_NOPAGE | VM_FAULT_RETRY)))
@@ -3720,10 +3722,10 @@ static int do_shared_fault(struct vm_fault *vmf)
* The mmap_sem may have been released depending on flags and our
* return value. See filemap_fault() and __lock_page_or_retry().
*/
-static int do_fault(struct vm_fault *vmf)
+static vm_fault_t do_fault(struct vm_fault *vmf)
{
struct vm_area_struct *vma = vmf->vma;
- int ret;
+ vm_fault_t ret;

/* The VMA was not fully populated on mmap() or missing VM_DONTEXPAND */
if (!vma->vm_ops->fault)
@@ -3758,7 +3760,7 @@ static int numa_migrate_prep(struct page *page, struct vm_area_struct *vma,
return mpol_misplaced(page, vma, addr);
}

-static int do_numa_page(struct vm_fault *vmf)
+static vm_fault_t do_numa_page(struct vm_fault *vmf)
{
struct vm_area_struct *vma = vmf->vma;
struct page *page = NULL;
@@ -3848,7 +3850,7 @@ static int do_numa_page(struct vm_fault *vmf)
return 0;
}

-static inline int create_huge_pmd(struct vm_fault *vmf)
+static inline vm_fault_t create_huge_pmd(struct vm_fault *vmf)
{
if (vma_is_anonymous(vmf->vma))
return do_huge_pmd_anonymous_page(vmf);
@@ -3858,7 +3860,7 @@ static inline int create_huge_pmd(struct vm_fault *vmf)
}

/* `inline' is required to avoid gcc 4.1.2 build error */
-static inline int wp_huge_pmd(struct vm_fault *vmf, pmd_t orig_pmd)
+static inline vm_fault_t wp_huge_pmd(struct vm_fault *vmf, pmd_t orig_pmd)
{
if (vma_is_anonymous(vmf->vma))
return do_huge_pmd_wp_page(vmf, orig_pmd);
@@ -3877,7 +3879,7 @@ static inline bool vma_is_accessible(struct vm_area_struct *vma)
return vma->vm_flags & (VM_READ | VM_EXEC | VM_WRITE);
}

-static int create_huge_pud(struct vm_fault *vmf)
+static vm_fault_t create_huge_pud(struct vm_fault *vmf)
{
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
/* No support for anonymous transparent PUD pages yet */
@@ -3889,7 +3891,7 @@ static int create_huge_pud(struct vm_fault *vmf)
return VM_FAULT_FALLBACK;
}

-static int wp_huge_pud(struct vm_fault *vmf, pud_t orig_pud)
+static vm_fault_t wp_huge_pud(struct vm_fault *vmf, pud_t orig_pud)
{
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
/* No support for anonymous transparent PUD pages yet */
@@ -3916,7 +3918,7 @@ static int wp_huge_pud(struct vm_fault *vmf, pud_t orig_pud)
* The mmap_sem may have been released depending on flags and our return value.
* See filemap_fault() and __lock_page_or_retry().
*/
-static int handle_pte_fault(struct vm_fault *vmf)
+static vm_fault_t handle_pte_fault(struct vm_fault *vmf)
{
pte_t entry;

@@ -4004,8 +4006,8 @@ static int handle_pte_fault(struct vm_fault *vmf)
* The mmap_sem may have been released depending on flags and our
* return value. See filemap_fault() and __lock_page_or_retry().
*/
-static int __handle_mm_fault(struct vm_area_struct *vma, unsigned long address,
- unsigned int flags)
+static vm_fault_t __handle_mm_fault(struct vm_area_struct *vma,
+ unsigned long address, unsigned int flags)
{
struct vm_fault vmf = {
.vma = vma,
@@ -4018,7 +4020,7 @@ static int __handle_mm_fault(struct vm_area_struct *vma, unsigned long address,
struct mm_struct *mm = vma->vm_mm;
pgd_t *pgd;
p4d_t *p4d;
- int ret;
+ vm_fault_t ret;

pgd = pgd_offset(mm, address);
p4d = p4d_alloc(mm, pgd, address);
@@ -4093,10 +4095,10 @@ static int __handle_mm_fault(struct vm_area_struct *vma, unsigned long address,
* The mmap_sem may have been released depending on flags and our
* return value. See filemap_fault() and __lock_page_or_retry().
*/
-int handle_mm_fault(struct vm_area_struct *vma, unsigned long address,
+vm_fault_t handle_mm_fault(struct vm_area_struct *vma, unsigned long address,
unsigned int flags)
{
- int ret;
+ vm_fault_t ret;

__set_current_state(TASK_RUNNING);

diff --git a/mm/shmem.c b/mm/shmem.c
index 9d6c7e5..af05c35 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -123,7 +123,7 @@ static int shmem_replace_page(struct page **pagep, gfp_t gfp,
static int shmem_getpage_gfp(struct inode *inode, pgoff_t index,
struct page **pagep, enum sgp_type sgp,
gfp_t gfp, struct vm_area_struct *vma,
- struct vm_fault *vmf, int *fault_type);
+ struct vm_fault *vmf, vm_fault_t *fault_type);

int shmem_getpage(struct inode *inode, pgoff_t index,
struct page **pagep, enum sgp_type sgp)
@@ -1604,7 +1604,8 @@ static int shmem_replace_page(struct page **pagep, gfp_t gfp,
*/
static int shmem_getpage_gfp(struct inode *inode, pgoff_t index,
struct page **pagep, enum sgp_type sgp, gfp_t gfp,
- struct vm_area_struct *vma, struct vm_fault *vmf, int *fault_type)
+ struct vm_area_struct *vma, struct vm_fault *vmf,
+ vm_fault_t *fault_type)
{
struct address_space *mapping = inode->i_mapping;
struct shmem_inode_info *info = SHMEM_I(inode);
@@ -1931,14 +1932,14 @@ static int synchronous_wake_function(wait_queue_entry_t *wait, unsigned mode, in
return ret;
}

-static int shmem_fault(struct vm_fault *vmf)
+static vm_fault_t shmem_fault(struct vm_fault *vmf)
{
struct vm_area_struct *vma = vmf->vma;
struct inode *inode = file_inode(vma->vm_file);
gfp_t gfp = mapping_gfp_mask(inode->i_mapping);
enum sgp_type sgp;
- int error;
- int ret = VM_FAULT_LOCKED;
+ int err;
+ vm_fault_t ret = VM_FAULT_LOCKED;

/*
* Trinity finds that probing a hole which tmpfs is punching can
@@ -2006,10 +2007,10 @@ static int shmem_fault(struct vm_fault *vmf)
else if (vma->vm_flags & VM_HUGEPAGE)
sgp = SGP_HUGE;

- error = shmem_getpage_gfp(inode, vmf->pgoff, &vmf->page, sgp,
+ err = shmem_getpage_gfp(inode, vmf->pgoff, &vmf->page, sgp,
gfp, vma, vmf, &ret);
- if (error)
- return ((error == -ENOMEM) ? VM_FAULT_OOM : VM_FAULT_SIGBUS);
+ if (err)
+ ret = vmf_error(err);
return ret;
}

--
1.9.1