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authorSouptick Joarder <jrdr.linux@gmail.com>2018-08-23 17:01:36 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2018-08-23 18:48:44 -0700
commit2b7403035459c75e193c6b04a293e518a4212de0 (patch)
treed553df6f3c3cac0ae3a3de3a1fcc9f2729d01ea8 /mm/memory.c
parenta99237afc12ba697159ca313525dc390737dd52f (diff)
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>
Diffstat (limited to 'mm/memory.c')
-rw-r--r--mm/memory.c90
1 files changed, 46 insertions, 44 deletions
diff --git a/mm/memory.c b/mm/memory.c
index 19f47d7b9b86..42ebdc33268e 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -2384,9 +2384,9 @@ 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;
@@ -2490,7 +2490,7 @@ 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;
@@ -2638,7 +2638,7 @@ oom:
* 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,
@@ -2659,12 +2659,12 @@ 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;
@@ -2677,7 +2677,7 @@ 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;
@@ -2685,7 +2685,7 @@ 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);
@@ -2728,7 +2728,7 @@ 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;
@@ -2904,7 +2904,7 @@ EXPORT_SYMBOL(unmap_mapping_range);
* 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;
@@ -2913,7 +2913,7 @@ 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;
@@ -3124,12 +3124,12 @@ out_release:
* 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 ? */
@@ -3239,10 +3239,10 @@ oom:
* 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 |
@@ -3276,7 +3276,7 @@ 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;
@@ -3352,13 +3352,14 @@ 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;
@@ -3408,7 +3409,7 @@ out:
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;
@@ -3429,13 +3430,13 @@ 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)) {
@@ -3494,10 +3495,10 @@ 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) &&
@@ -3583,12 +3584,13 @@ late_initcall(fault_around_debugfs);
* (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;
@@ -3638,10 +3640,10 @@ out:
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
@@ -3665,10 +3667,10 @@ 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;
@@ -3704,10 +3706,10 @@ uncharge_out:
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)))
@@ -3745,10 +3747,10 @@ 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)
@@ -3783,7 +3785,7 @@ 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;
@@ -3873,7 +3875,7 @@ out:
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);
@@ -3883,7 +3885,7 @@ 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);
@@ -3902,7 +3904,7 @@ 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 */
@@ -3914,7 +3916,7 @@ 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 */
@@ -3941,7 +3943,7 @@ 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;
@@ -4029,8 +4031,8 @@ unlock:
* 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,
@@ -4043,7 +4045,7 @@ 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);
@@ -4118,10 +4120,10 @@ 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);