[PATCH v3 5/9] xen/tmem: Use xen_page_to_gfn rather than pfn_to_gfn

[Julien Grall <julien.grall@citrix.com>]

All the caller of xen_tmem_{get,put}_page have a struct page * in hand
and call pfn_to_gfn for the only benefits of these 2 functions.

Rather than passing the pfn in parameter, pass directly the page and use
directly xen_page_to_gfn.

Signed-off-by: Julien Grall <julien.grall@citrix.com>
Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>

---
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: David Vrabel <david.vrabel@citrix.com>

    Changes in v3:
        - Add Stefano's reviewed-by
        - page_to_gfn has been renamed to xen_page_to_gfn
---
 drivers/xen/tmem.c | 21 +++++++--------------
 1 file changed, 7 insertions(+), 14 deletions(-)

diff --git a/drivers/xen/tmem.c b/drivers/xen/tmem.c
index 28c97ff..b0c895e 100644
--- a/drivers/xen/tmem.c
+++ b/drivers/xen/tmem.c
@@ -129,21 +129,17 @@ static int xen_tmem_new_pool(struct tmem_pool_uuid uuid,
 /* xen generic tmem ops */
 
 static int xen_tmem_put_page(u32 pool_id, struct tmem_oid oid,
-			     u32 index, unsigned long pfn)
+			     u32 index, struct page *page)
 {
-	unsigned long gmfn = pfn_to_gfn(pfn);
-
 	return xen_tmem_op(TMEM_PUT_PAGE, pool_id, oid, index,
-		gmfn, 0, 0, 0);
+			   xen_page_to_gfn(page), 0, 0, 0);
 }
 
 static int xen_tmem_get_page(u32 pool_id, struct tmem_oid oid,
-			     u32 index, unsigned long pfn)
+			     u32 index, struct page *page)
 {
-	unsigned long gmfn = pfn_to_gfn(pfn);
-
 	return xen_tmem_op(TMEM_GET_PAGE, pool_id, oid, index,
-		gmfn, 0, 0, 0);
+			   xen_page_to_gfn(page), 0, 0, 0);
 }
 
 static int xen_tmem_flush_page(u32 pool_id, struct tmem_oid oid, u32 index)
@@ -173,14 +169,13 @@ static void tmem_cleancache_put_page(int pool, struct cleancache_filekey key,
 {
 	u32 ind = (u32) index;
 	struct tmem_oid oid = *(struct tmem_oid *)&key;
-	unsigned long pfn = page_to_pfn(page);
 
 	if (pool < 0)
 		return;
 	if (ind != index)
 		return;
 	mb(); /* ensure page is quiescent; tmem may address it with an alias */
-	(void)xen_tmem_put_page((u32)pool, oid, ind, pfn);
+	(void)xen_tmem_put_page((u32)pool, oid, ind, page);
 }
 
 static int tmem_cleancache_get_page(int pool, struct cleancache_filekey key,
@@ -287,7 +282,6 @@ static int tmem_frontswap_store(unsigned type, pgoff_t offset,
 {
 	u64 ind64 = (u64)offset;
 	u32 ind = (u32)offset;
-	unsigned long pfn = page_to_pfn(page);
 	int pool = tmem_frontswap_poolid;
 	int ret;
 
@@ -296,7 +290,7 @@ static int tmem_frontswap_store(unsigned type, pgoff_t offset,
 	if (ind64 != ind)
 		return -1;
 	mb(); /* ensure page is quiescent; tmem may address it with an alias */
-	ret = xen_tmem_put_page(pool, oswiz(type, ind), iswiz(ind), pfn);
+	ret = xen_tmem_put_page(pool, oswiz(type, ind), iswiz(ind), page);
 	/* translate Xen tmem return values to linux semantics */
 	if (ret == 1)
 		return 0;
@@ -313,7 +307,6 @@ static int tmem_frontswap_load(unsigned type, pgoff_t offset,
 {
 	u64 ind64 = (u64)offset;
 	u32 ind = (u32)offset;
-	unsigned long pfn = page_to_pfn(page);
 	int pool = tmem_frontswap_poolid;
 	int ret;
 
@@ -321,7 +314,7 @@ static int tmem_frontswap_load(unsigned type, pgoff_t offset,
 		return -1;
 	if (ind64 != ind)
 		return -1;
-	ret = xen_tmem_get_page(pool, oswiz(type, ind), iswiz(ind), pfn);
+	ret = xen_tmem_get_page(pool, oswiz(type, ind), iswiz(ind), page);
 	/* translate Xen tmem return values to linux semantics */
 	if (ret == 1)
 		return 0;
-- 
2.1.4