Constructs like 'var & (PAGE_SIZE - 1)' or 'var & ~PAGE_MASK' can be
replaced by the offset_in_page() macro instead of open-coding it.
Add a coccinelle semantic patch to ease detection and conversion of these.
This unfortunately doesn't account for the case when we want PAGE_ALIGNED()
instead of offset_in_page() yet.
Cc: Julia Lawall <julia.law...@lip6.fr>
Signed-off-by: Johannes Thumshirn <jthumsh...@suse.de>
---
scripts/coccinelle/api/offset_in_page.cocci | 81 +++++++++++++++++++++++++++++
1 file changed, 81 insertions(+)
create mode 100644 scripts/coccinelle/api/offset_in_page.cocci
diff --git a/scripts/coccinelle/api/offset_in_page.cocci
b/scripts/coccinelle/api/offset_in_page.cocci
new file mode 100644
index 000000000000..ea5b3a8e0390
--- /dev/null
+++ b/scripts/coccinelle/api/offset_in_page.cocci
@@ -0,0 +1,81 @@
+// SPDX-License-Identifier: GPL-2.0
+///
+/// Use offset_in_page macro on address instead of explicit computation.
+///
+// Confidence: High
+// Keywords: offset_in_page
+// Comment: Based on vma_pages.cocci
+
+virtual context
+virtual patch
+virtual org
+virtual report
+
+
+//----------------------------------------------------------
+// For context mode
+//----------------------------------------------------------
+
+@r_context depends on context && !patch && !org && !report@
+expression E;
+@@
+
+(
+* E & ~PAGE_MASK
+|
+* E & (PAGE_SIZE - 1)
+)
+
+
+//----------------------------------------------------------
+// For patch mode
+//----------------------------------------------------------
+
+@r_patch depends on !context && patch && !org && !report@
+expression E;
+type T;
+@@
+
+(
+- E & ~PAGE_MASK
++ offset_in_page(E)
+|
+- E & (PAGE_SIZE - 1)
++ offset_in_page(E)
+|
+- E & ((T)PAGE_SIZE - 1)
++ offset_in_page(E)
+)
+
+//----------------------------------------------------------
+// For org mode
+//----------------------------------------------------------
+
+@r_org depends on !context && !patch && (org || report)@
+expression E;
+position p;
+@@
+
+ (
+ * E@p & ~PAGE_MASK
+ |
+ * E@p & (PAGE_SIZE - 1)
+ )
+
+@script:python depends on report@
+p << r_org.p;
+x << r_org.E;
+@@
+
+msg="WARNING: Consider using offset_in_page helper on %s" % (x)
+coccilib.report.print_report(p[0], msg)
+
+@script:python depends on org@
+p << r_org.p;
+x << r_org.E;
+@@
+
+msg="WARNING: Consider using offset_in_page helper on %s" % (x)
+msg_safe=msg.replace("[","@(").replace("]",")")
+coccilib.org.print_todo(p[0], msg_safe)
+
--
2.16.4
