FROMLIST: mm: introduce __vm_normal_page()

When dealing with the speculative fault path we should use the VMA's field
cached value stored in the vm_fault structure.

Currently vm_normal_page() is using the pointer to the VMA to fetch the
vm_flags value. This patch provides a new __vm_normal_page() which is
receiving the vm_flags flags value as parameter.

Note: The speculative path is turned on for architecture providing support
for special PTE flag. So only the first block of vm_normal_page is used
during the speculative path.

Change-Id: I0f2c4ab1212fbca449bdf6e7993dafa0d41044bc
Signed-off-by: Laurent Dufour <ldufour@linux.vnet.ibm.com>
Link: https://lore.kernel.org/lkml/1523975611-15978-16-git-send-email-ldufour@linux.vnet.ibm.com/
Bug: 161210518
Signed-off-by: Vinayak Menon <vinmenon@codeaurora.org>
Signed-off-by: Charan Teja Reddy <charante@codeaurora.org>
This commit is contained in:
Laurent Dufour 2018-04-17 16:33:21 +02:00 committed by Suren Baghdasaryan
parent cbff8f3907
commit 10a5eb6be8
2 changed files with 23 additions and 11 deletions

View File

@ -1669,8 +1669,14 @@ struct zap_details {
pgoff_t last_index; /* Highest page->index to unmap */
};
struct page *vm_normal_page(struct vm_area_struct *vma, unsigned long addr,
pte_t pte);
struct page *_vm_normal_page(struct vm_area_struct *vma, unsigned long addr,
pte_t pte, unsigned long vma_flags);
static inline struct page *vm_normal_page(struct vm_area_struct *vma,
unsigned long addr, pte_t pte)
{
return _vm_normal_page(vma, addr, pte, vma->vm_flags);
}
struct page *vm_normal_page_pmd(struct vm_area_struct *vma, unsigned long addr,
pmd_t pmd);

View File

@ -568,7 +568,8 @@ static void print_bad_pte(struct vm_area_struct *vma, unsigned long addr,
}
/*
* vm_normal_page -- This function gets the "struct page" associated with a pte.
* __vm_normal_page -- This function gets the "struct page" associated with
* a pte.
*
* "Special" mappings do not wish to be associated with a "struct page" (either
* it doesn't exist, or it exists but they don't want to touch it). In this
@ -609,8 +610,8 @@ static void print_bad_pte(struct vm_area_struct *vma, unsigned long addr,
* PFNMAP mappings in order to support COWable mappings.
*
*/
struct page *vm_normal_page(struct vm_area_struct *vma, unsigned long addr,
pte_t pte)
struct page *_vm_normal_page(struct vm_area_struct *vma, unsigned long addr,
pte_t pte, unsigned long vma_flags)
{
unsigned long pfn = pte_pfn(pte);
@ -619,7 +620,7 @@ struct page *vm_normal_page(struct vm_area_struct *vma, unsigned long addr,
goto check_pfn;
if (vma->vm_ops && vma->vm_ops->find_special_page)
return vma->vm_ops->find_special_page(vma, addr);
if (vma->vm_flags & (VM_PFNMAP | VM_MIXEDMAP))
if (vma_flags & (VM_PFNMAP | VM_MIXEDMAP))
return NULL;
if (is_zero_pfn(pfn))
return NULL;
@ -631,9 +632,13 @@ struct page *vm_normal_page(struct vm_area_struct *vma, unsigned long addr,
}
/* !CONFIG_ARCH_HAS_PTE_SPECIAL case follows: */
/*
* This part should never get called when CONFIG_SPECULATIVE_PAGE_FAULT
* is set. This is mainly because we can't rely on vm_start.
*/
if (unlikely(vma->vm_flags & (VM_PFNMAP|VM_MIXEDMAP))) {
if (vma->vm_flags & VM_MIXEDMAP) {
if (unlikely(vma_flags & (VM_PFNMAP|VM_MIXEDMAP))) {
if (vma_flags & VM_MIXEDMAP) {
if (!pfn_valid(pfn))
return NULL;
goto out;
@ -642,7 +647,7 @@ struct page *vm_normal_page(struct vm_area_struct *vma, unsigned long addr,
off = (addr - vma->vm_start) >> PAGE_SHIFT;
if (pfn == vma->vm_pgoff + off)
return NULL;
if (!is_cow_mapping(vma->vm_flags))
if (!is_cow_mapping(vma_flags))
return NULL;
}
}
@ -3137,7 +3142,8 @@ static vm_fault_t do_wp_page(struct vm_fault *vmf)
return handle_userfault(vmf, VM_UFFD_WP);
}
vmf->page = vm_normal_page(vma, vmf->address, vmf->orig_pte);
vmf->page = _vm_normal_page(vma, vmf->address, vmf->orig_pte,
vmf->vma_flags);
if (!vmf->page) {
/*
* VM_MIXEDMAP !pfn_valid() case, or VM_SOFTDIRTY clear on a
@ -4279,7 +4285,7 @@ static vm_fault_t do_numa_page(struct vm_fault *vmf)
ptep_modify_prot_commit(vma, vmf->address, vmf->pte, old_pte, pte);
update_mmu_cache(vma, vmf->address, vmf->pte);
page = vm_normal_page(vma, vmf->address, pte);
page = _vm_normal_page(vma, vmf->address, pte, vmf->vma_flags);
if (!page) {
pte_unmap_unlock(vmf->pte, vmf->ptl);
return 0;