vsprintf: Make %pGp print the hex value

All existing users of %pGp want the hex value as well as the decoded
flag names.  This looks awkward (passing the same parameter to printf
twice), so move that functionality into the core.  If we want, we
can make that optional with flag arguments to %pGp in the future.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Yafang Shao <laoar.shao@gmail.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20211019142621.2810043-6-willy@infradead.org

6 files changed, 24 insertions, 11 deletions

diff --git a/lib/test_printf.c b/lib/test_printf.c
index d09993fca463..07309c45f327 100644
--- a/lib/test_printf.c
+++ b/lib/test_printf.c
@@ -609,10 +609,14 @@ page_flags_test(int section, int node, int zone, int last_cpupid,
 		char *cmp_buf)
 {
 	unsigned long values[] = {section, node, zone, last_cpupid, kasan_tag};
-	unsigned long size = 0;
+	unsigned long size;
 	bool append = false;
 	int i;
 
+	for (i = 0; i < ARRAY_SIZE(values); i++)
+		flags |= (values[i] & pft[i].mask) << pft[i].shift;
+
+	size = scnprintf(cmp_buf, BUF_SIZE, "%#lx(", flags);
 	if (flags & PAGEFLAGS_MASK) {
 		size += scnprintf(cmp_buf + size, BUF_SIZE - size, "%s", name);
 		append = true;
@@ -625,7 +629,6 @@ page_flags_test(int section, int node, int zone, int last_cpupid,
 		if (append)
 			size += scnprintf(cmp_buf + size, BUF_SIZE - size, "|");
 
-		flags |= (values[i] & pft[i].mask) << pft[i].shift;
 		size += scnprintf(cmp_buf + size, BUF_SIZE - size, "%s=",
 				pft[i].name);
 		size += scnprintf(cmp_buf + size, BUF_SIZE - size, pft[i].fmt,
@@ -633,6 +636,8 @@ page_flags_test(int section, int node, int zone, int last_cpupid,
 		append = true;
 	}
 
+	snprintf(cmp_buf + size, BUF_SIZE - size, ")");
+
 	test(cmp_buf, "%pGp", &flags);
 }
 
diff --git a/lib/vsprintf.c b/lib/vsprintf.c
index d7ad44f2c8f5..214098248610 100644
--- a/lib/vsprintf.c
+++ b/lib/vsprintf.c
@@ -2023,6 +2023,11 @@ char *format_page_flags(char *buf, char *end, unsigned long flags)
 	bool append = false;
 	int i;
 
+	buf = number(buf, end, flags, default_flag_spec);
+	if (buf < end)
+		*buf = '(';
+	buf++;
+
 	/* Page flags from the main area. */
 	if (main_flags) {
 		buf = format_flags(buf, end, main_flags, pageflag_names);
@@ -2051,6 +2056,9 @@ char *format_page_flags(char *buf, char *end, unsigned long flags)
 
 		append = true;
 	}
+	if (buf < end)
+		*buf = ')';
+	buf++;
 
 	return buf;
 }
diff --git a/mm/debug.c b/mm/debug.c
index e73fe0a8ec3d..ca9611784e4b 100644
--- a/mm/debug.c
+++ b/mm/debug.c
@@ -160,7 +160,7 @@ static void __dump_page(struct page *page)
 out_mapping:
 	BUILD_BUG_ON(ARRAY_SIZE(pageflag_names) != __NR_PAGEFLAGS + 1);
 
-	pr_warn("%sflags: %#lx(%pGp)%s\n", type, head->flags, &head->flags,
+	pr_warn("%sflags: %pGp%s\n", type, &head->flags,
 		page_cma ? " CMA" : "");
 	print_hex_dump(KERN_WARNING, "raw: ", DUMP_PREFIX_NONE, 32,
 			sizeof(unsigned long), page,
diff --git a/mm/memory-failure.c b/mm/memory-failure.c
index 54879c339024..58ab5161a8ce 100644
--- a/mm/memory-failure.c
+++ b/mm/memory-failure.c
@@ -2109,14 +2109,14 @@ static int __soft_offline_page(struct page *page)
 			if (!list_empty(&pagelist))
 				putback_movable_pages(&pagelist);
 
-			pr_info("soft offline: %#lx: %s migration failed %d, type %lx (%pGp)\n",
-				pfn, msg_page[huge], ret, page->flags, &page->flags);
+			pr_info("soft offline: %#lx: %s migration failed %d, type %pGp\n",
+				pfn, msg_page[huge], ret, &page->flags);
 			if (ret > 0)
 				ret = -EBUSY;
 		}
 	} else {
-		pr_info("soft offline: %#lx: %s isolation failed, page count %d, type %lx (%pGp)\n",
-			pfn, msg_page[huge], page_count(page), page->flags, &page->flags);
+		pr_info("soft offline: %#lx: %s isolation failed, page count %d, type %pGp\n",
+			pfn, msg_page[huge], page_count(page), &page->flags);
 		ret = -EBUSY;
 	}
 	return ret;
diff --git a/mm/page_owner.c b/mm/page_owner.c
index 62402d22539b..4afc713ca525 100644
--- a/mm/page_owner.c
+++ b/mm/page_owner.c
@@ -351,12 +351,12 @@ print_page_owner(char __user *buf, size_t count, unsigned long pfn,
 	pageblock_mt = get_pageblock_migratetype(page);
 	page_mt  = gfp_migratetype(page_owner->gfp_mask);
 	ret += snprintf(kbuf + ret, count - ret,
-			"PFN %lu type %s Block %lu type %s Flags %#lx(%pGp)\n",
+			"PFN %lu type %s Block %lu type %s Flags %pGp\n",
 			pfn,
 			migratetype_names[page_mt],
 			pfn >> pageblock_order,
 			migratetype_names[pageblock_mt],
-			page->flags, &page->flags);
+			&page->flags);
 
 	if (ret >= count)
 		goto err;
diff --git a/mm/slub.c b/mm/slub.c
index 3d2025f7163b..f7ac28646580 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -763,9 +763,9 @@ void print_tracking(struct kmem_cache *s, void *object)
 
 static void print_page_info(struct page *page)
 {
-	pr_err("Slab 0x%p objects=%u used=%u fp=0x%p flags=%#lx(%pGp)\n",
+	pr_err("Slab 0x%p objects=%u used=%u fp=0x%p flags=%pGp\n",
 	       page, page->objects, page->inuse, page->freelist,
-	       page->flags, &page->flags);
+	       &page->flags);
 
 }