[RFC][PATCH 03/10] x86/mm/cpa: Add __cpa_addr() helper

From: Peter Zijlstra
Date: Mon Dec 03 2018 - 12:15:18 EST


The code to compute the virtual address of a cpa_data is duplicated;
introduce a helper before more copies happen.

Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
---
arch/x86/mm/pageattr.c | 38 +++++++++++++++++++-------------------
1 file changed, 19 insertions(+), 19 deletions(-)

--- a/arch/x86/mm/pageattr.c
+++ b/arch/x86/mm/pageattr.c
@@ -228,6 +228,23 @@ static bool __cpa_pfn_in_highmap(unsigne

#endif

+static unsigned long __cpa_addr(struct cpa_data *cpa, int idx)
+{
+ if (cpa->flags & CPA_PAGES_ARRAY) {
+ struct page *page = cpa->pages[idx];
+
+ if (unlikely(PageHighMem(page)))
+ return 0;
+
+ return (unsigned long)page_address(page);
+ }
+
+ if (cpa->flags & CPA_ARRAY)
+ return cpa->vaddr[idx];
+
+ return *cpa->vaddr;
+}
+
/*
* Flushing functions
*/
@@ -1468,15 +1485,7 @@ static int __change_page_attr(struct cpa
unsigned int level;
pte_t *kpte, old_pte;

- if (cpa->flags & CPA_PAGES_ARRAY) {
- struct page *page = cpa->pages[cpa->curpage];
- if (unlikely(PageHighMem(page)))
- return 0;
- address = (unsigned long)page_address(page);
- } else if (cpa->flags & CPA_ARRAY)
- address = cpa->vaddr[cpa->curpage];
- else
- address = *cpa->vaddr;
+ address = __cpa_addr(cpa, cpa->curpage);
repeat:
kpte = _lookup_address_cpa(cpa, address, &level);
if (!kpte)
@@ -1557,16 +1566,7 @@ static int cpa_process_alias(struct cpa_
* No need to redo, when the primary call touched the direct
* mapping already:
*/
- if (cpa->flags & CPA_PAGES_ARRAY) {
- struct page *page = cpa->pages[cpa->curpage];
- if (unlikely(PageHighMem(page)))
- return 0;
- vaddr = (unsigned long)page_address(page);
- } else if (cpa->flags & CPA_ARRAY)
- vaddr = cpa->vaddr[cpa->curpage];
- else
- vaddr = *cpa->vaddr;
-
+ vaddr = __cpa_addr(cpa, cpa->curpage);
if (!(within(vaddr, PAGE_OFFSET,
PAGE_OFFSET + (max_pfn_mapped << PAGE_SHIFT)))) {