On Wed, 2020-04-22 at 11:57 +0200, Greg Kroah-Hartman wrote:
> From: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
>
> [ Upstream commit 44a52022e7f15cbaab957df1c14f7a4f527ef7cf ]
>
> When EXT2_ATTR_DEBUG is not defined, modify the 2 debug macros
> to use the no_printk() macro instead of <nothing>.
> This fixes gcc warnings when -Wextra is used:
>
> ../fs/ext2/xattr.c:252:42: warning: suggest braces around empty body in an ‘if’ statement [-Wempty-body]
> ../fs/ext2/xattr.c:258:42: warning: suggest braces around empty body in an ‘if’ statement [-Wempty-body]
> ../fs/ext2/xattr.c:330:42: warning: suggest braces around empty body in an ‘if’ statement [-Wempty-body]
> ../fs/ext2/xattr.c:872:45: warning: suggest braces around empty body in an ‘else’ statement [-Wempty-body]
>
> I have verified that the only object code change (with gcc 7.5.0) is
> the reversal of some instructions from 'cmp a,b' to 'cmp b,a'.
It'd be better to use the ext4 style defines:
fs/ext4/xattr.c:# define ea_idebug(inode, fmt, ...) \
fs/ext4/xattr.c- printk(KERN_DEBUG "inode %s:%lu: " fmt "\n", \
fs/ext4/xattr.c- inode->i_sb->s_id, inode->i_ino, ##__VA_ARGS__)
fs/ext4/xattr.c:# define ea_bdebug(bh, fmt, ...) \
fs/ext4/xattr.c- printk(KERN_DEBUG "block %pg:%lu: " fmt "\n", \
fs/ext4/xattr.c- bh->b_bdev, (unsigned long)bh->b_blocknr, ##__VA_ARGS__)
--
fs/ext4/xattr.c:# define ea_idebug(inode, fmt, ...) no_printk(fmt, ##__VA_ARGS__)
fs/ext4/xattr.c:# define ea_bdebug(bh, fmt, ...) no_printk(fmt, ##__VA_ARGS__)
So the output logging won't be split across multiple lines.
> diff --git a/fs/ext2/xattr.c b/fs/ext2/xattr.c
[]
> @@ -55,6 +55,7 @@
>
> #include <linux/buffer_head.h>
> #include <linux/init.h>
> +#include <linux/printk.h>
> #include <linux/slab.h>
> #include <linux/mbcache.h>
> #include <linux/quotaops.h>
> @@ -85,8 +86,8 @@
> printk("\n"); \
> } while (0)
> #else
> -# define ea_idebug(f...)
> -# define ea_bdebug(f...)
> +# define ea_idebug(inode, f...) no_printk(f)
> +# define ea_bdebug(bh, f...) no_printk(f)
> #endif
>
> static int ext2_xattr_set2(struct inode *, struct buffer_head *,
---
fs/ext2/xattr.c | 22 ++++++++--------------
1 file changed, 8 insertions(+), 14 deletions(-)
diff --git a/fs/ext2/xattr.c b/fs/ext2/xattr.c
index 943cc46..7740582 100644
--- a/fs/ext2/xattr.c
+++ b/fs/ext2/xattr.c
@@ -72,21 +72,15 @@
#define IS_LAST_ENTRY(entry) (*(__u32 *)(entry) == 0)
#ifdef EXT2_XATTR_DEBUG
-# define ea_idebug(inode, f...) do { \
- printk(KERN_DEBUG "inode %s:%ld: ", \
- inode->i_sb->s_id, inode->i_ino); \
- printk(f); \
- printk("\n"); \
- } while (0)
-# define ea_bdebug(bh, f...) do { \
- printk(KERN_DEBUG "block %pg:%lu: ", \
- bh->b_bdev, (unsigned long) bh->b_blocknr); \
- printk(f); \
- printk("\n"); \
- } while (0)
+# define ea_idebug(inode, fmt, ...) \
+ printk(KERN_DEBUG "inode %s:%lu: " fmt "\n", \
+ inode->i_sb->s_id, inode->i_ino, ##__VA_ARGS__)
+# define ea_bdebug(bh, fmt, ...) \
+ printk(KERN_DEBUG "block %pg:%lu: " fmt "\n", \
+ bh->b_bdev, (unsigned long)bh->b_blocknr, ##__VA_ARGS__)
#else
-# define ea_idebug(inode, f...) no_printk(f)
-# define ea_bdebug(bh, f...) no_printk(f)
+# define ea_idebug(inode, fmt, ...) no_printk(fmt, ##__VA_ARGS__)
+# define ea_bdebug(bh, fmt, ...) no_printk(fmt, ##__VA_ARGS__)
#endif
static int ext2_xattr_set2(struct inode *, struct buffer_head *,
