exfat: Expand exfat_err() and co directly to pr_*() macro

Currently the error and info messages handled by exfat_err() and co
are tossed to exfat_msg() function that does nothing but passes the
strings with printk() invocation.  Not only that this is more overhead
by the indirect calls, but also this makes harder to extend for the
debug print usage; because of the direct printk() call, you cannot
make it for dynamic debug or without debug like the standard helpers
such as pr_debug() or dev_dbg().

For addressing the problem, this patch replaces exfat_*() macro to
expand to pr_*() directly.  Along with it, add the new exfat_debug()
macro that is expanded to pr_debug() (which output can be gracefully
suppressed via dyndbg).
Reviewed-by: Petr Vorel <pvorel@suse.cz>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>

fs/exfat/exfat_fs.h

@@ -509,14 +509,16 @@ void __exfat_fs_error(struct super_block *sb, int report, const char *fmt, ...)
 #define exfat_fs_error_ratelimit(sb, fmt, args...) \
 		__exfat_fs_error(sb, __ratelimit(&EXFAT_SB(sb)->ratelimit), \
 		fmt, ## args)
-void exfat_msg(struct super_block *sb, const char *lv, const char *fmt, ...)
-		__printf(3, 4) __cold;
+
+/* expand to pr_*() with prefix */
 #define exfat_err(sb, fmt, ...)						\
-	exfat_msg(sb, KERN_ERR, fmt, ##__VA_ARGS__)
+	pr_err("exFAT-fs (%s): " fmt "\n", (sb)->s_id, ##__VA_ARGS__)
 #define exfat_warn(sb, fmt, ...)					\
-	exfat_msg(sb, KERN_WARNING, fmt, ##__VA_ARGS__)
+	pr_warn("exFAT-fs (%s): " fmt "\n", (sb)->s_id, ##__VA_ARGS__)
 #define exfat_info(sb, fmt, ...)					\
-	exfat_msg(sb, KERN_INFO, fmt, ##__VA_ARGS__)
+	pr_info("exFAT-fs (%s): " fmt "\n", (sb)->s_id, ##__VA_ARGS__)
+#define exfat_debug(sb, fmt, ...)					\
+	pr_debug("exFAT-fs (%s): " fmt "\n", (sb)->s_id, ##__VA_ARGS__)
 
 void exfat_get_entry_time(struct exfat_sb_info *sbi, struct timespec64 *ts,
 		u8 tz, __le16 time, __le16 date, u8 time_cs);

fs/exfat/misc.c

@@ -46,23 +46,6 @@ void __exfat_fs_error(struct super_block *sb, int report, const char *fmt, ...)
 	}
 }
 
-/*
- * exfat_msg() - print preformated EXFAT specific messages.
- * All logs except what uses exfat_fs_error() should be written by exfat_msg()
- */
-void exfat_msg(struct super_block *sb, const char *level, const char *fmt, ...)
-{
-	struct va_format vaf;
-	va_list args;
-
-	va_start(args, fmt);
-	vaf.fmt = fmt;
-	vaf.va = &args;
-	/* level means KERN_ pacility level */
-	printk("%sexFAT-fs (%s): %pV\n", level, sb->s_id, &vaf);
-	va_end(args);
-}
-
 #define SECS_PER_MIN    (60)
 #define TIMEZONE_SEC(x)	((x) * 15 * SECS_PER_MIN)