Use vm_fault structure to pass cow_page, page, and entry in and out of
the function. That reduces number of __do_fault() arguments from 4 to 1.
Signed-off-by: Jan Kara <j...@suse.cz>
---
mm/memory.c | 53 +++++++++++++++++++++++------------------------------
1 file changed, 23 insertions(+), 30 deletions(-)
diff --git a/mm/memory.c b/mm/memory.c
index b7f1f535e079..ba7760fb7db2 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -2844,26 +2844,22 @@ 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, struct page *cow_page,
- struct page **page, void **entry)
+static int __do_fault(struct vm_fault *vmf)
{
struct vm_area_struct *vma = vmf->vma;
int ret;
- vmf->cow_page = cow_page;
-
ret = vma->vm_ops->fault(vma, vmf);
if (unlikely(ret & (VM_FAULT_ERROR | VM_FAULT_NOPAGE | VM_FAULT_RETRY)))
return ret;
- if (ret & VM_FAULT_DAX_LOCKED) {
- *entry = vmf->entry;
+ if (ret & VM_FAULT_DAX_LOCKED)
return ret;
- }
if (unlikely(PageHWPoison(vmf->page))) {
if (ret & VM_FAULT_LOCKED)
unlock_page(vmf->page);
put_page(vmf->page);
+ vmf->page = NULL;
return VM_FAULT_HWPOISON;
}
@@ -2872,7 +2868,6 @@ static int __do_fault(struct vm_fault *vmf, struct page
*cow_page,
else
VM_BUG_ON_PAGE(!PageLocked(vmf->page), vmf->page);
- *page = vmf->page;
return ret;
}
@@ -3169,7 +3164,6 @@ out:
static int do_read_fault(struct vm_fault *vmf)
{
struct vm_area_struct *vma = vmf->vma;
- struct page *fault_page;
int ret = 0;
/*
@@ -3183,24 +3177,23 @@ static int do_read_fault(struct vm_fault *vmf)
return ret;
}
- ret = __do_fault(vmf, NULL, &fault_page, NULL);
+ ret = __do_fault(vmf);
if (unlikely(ret & (VM_FAULT_ERROR | VM_FAULT_NOPAGE | VM_FAULT_RETRY)))
return ret;
- ret |= alloc_set_pte(vmf, NULL, fault_page);
+ ret |= alloc_set_pte(vmf, NULL, vmf->page);
if (vmf->pte)
pte_unmap_unlock(vmf->pte, vmf->ptl);
- unlock_page(fault_page);
+ unlock_page(vmf->page);
if (unlikely(ret & (VM_FAULT_ERROR | VM_FAULT_NOPAGE | VM_FAULT_RETRY)))
- put_page(fault_page);
+ put_page(vmf->page);
return ret;
}
static int do_cow_fault(struct vm_fault *vmf)
{
struct vm_area_struct *vma = vmf->vma;
- struct page *fault_page, *new_page;
- void *fault_entry;
+ struct page *new_page;
struct mem_cgroup *memcg;
int ret;
@@ -3217,20 +3210,21 @@ static int do_cow_fault(struct vm_fault *vmf)
return VM_FAULT_OOM;
}
- ret = __do_fault(vmf, new_page, &fault_page, &fault_entry);
+ vmf->cow_page = new_page;
+ ret = __do_fault(vmf);
if (unlikely(ret & (VM_FAULT_ERROR | VM_FAULT_NOPAGE | VM_FAULT_RETRY)))
goto uncharge_out;
if (!(ret & VM_FAULT_DAX_LOCKED))
- copy_user_highpage(new_page, fault_page, vmf->address, vma);
+ copy_user_highpage(new_page, vmf->page, vmf->address, vma);
__SetPageUptodate(new_page);
ret |= alloc_set_pte(vmf, memcg, new_page);
if (vmf->pte)
pte_unmap_unlock(vmf->pte, vmf->ptl);
if (!(ret & VM_FAULT_DAX_LOCKED)) {
- unlock_page(fault_page);
- put_page(fault_page);
+ unlock_page(vmf->page);
+ put_page(vmf->page);
} else {
dax_unlock_mapping_entry(vma->vm_file->f_mapping, vmf->pgoff);
}
@@ -3246,12 +3240,11 @@ uncharge_out:
static int do_shared_fault(struct vm_fault *vmf)
{
struct vm_area_struct *vma = vmf->vma;
- struct page *fault_page;
struct address_space *mapping;
int dirtied = 0;
int ret, tmp;
- ret = __do_fault(vmf, NULL, &fault_page, NULL);
+ ret = __do_fault(vmf);
if (unlikely(ret & (VM_FAULT_ERROR | VM_FAULT_NOPAGE | VM_FAULT_RETRY)))
return ret;
@@ -3260,26 +3253,26 @@ static int do_shared_fault(struct vm_fault *vmf)
* about to become writable
*/
if (vma->vm_ops->page_mkwrite) {
- unlock_page(fault_page);
- tmp = do_page_mkwrite(vma, fault_page, vmf->address);
+ unlock_page(vmf->page);
+ tmp = do_page_mkwrite(vma, vmf->page, vmf->address);
if (unlikely(!tmp ||
(tmp & (VM_FAULT_ERROR | VM_FAULT_NOPAGE)))) {
- put_page(fault_page);
+ put_page(vmf->page);
return tmp;
}
}
- ret |= alloc_set_pte(vmf, NULL, fault_page);
+ ret |= alloc_set_pte(vmf, NULL, vmf->page);
if (vmf->pte)
pte_unmap_unlock(vmf->pte, vmf->ptl);
if (unlikely(ret & (VM_FAULT_ERROR | VM_FAULT_NOPAGE |
VM_FAULT_RETRY))) {
- unlock_page(fault_page);
- put_page(fault_page);
+ unlock_page(vmf->page);
+ put_page(vmf->page);
return ret;
}
- if (set_page_dirty(fault_page))
+ if (set_page_dirty(vmf->page))
dirtied = 1;
/*
* Take a local copy of the address_space - page.mapping may be zeroed
@@ -3287,8 +3280,8 @@ static int do_shared_fault(struct vm_fault *vmf)
* pinned by vma->vm_file's reference. We rely on unlock_page()'s
* release semantics to prevent the compiler from undoing this copying.
*/
- mapping = page_rmapping(fault_page);
- unlock_page(fault_page);
+ mapping = page_rmapping(vmf->page);
+ unlock_page(vmf->page);
if ((dirtied || vma->vm_ops->page_mkwrite) && mapping) {
/*
* Some device drivers do not set page.mapping but still
--
2.6.6
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