ext4: Combine proc file handling into a single set of functions

Previously mballoc created a separate set of functions for each proc
file.  This combines the tunables into a single set of functions which
gets used for all of the per-superblock proc files, saving
approximately 2k of compiled object code.
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

fs/ext4/ext4.h

@@ -957,6 +957,22 @@ void ext4_get_group_no_and_offset(struct super_block *sb, ext4_fsblk_t blocknr,
 
 extern struct proc_dir_entry *ext4_proc_root;
 
+#ifdef CONFIG_PROC_FS
+extern const struct file_operations ext4_ui_proc_fops;
+
+#define	EXT4_PROC_HANDLER(name, var)					\
+do {									\
+	proc = proc_create_data(name, mode, sbi->s_proc,		\
+				&ext4_ui_proc_fops, &sbi->s_##var);	\
+	if (proc == NULL) {						\
+		printk(KERN_ERR "EXT4-fs: can't create %s\n", name);	\
+		goto err_out;						\
+	}								\
+} while (0)
+#else
+#define EXT4_PROC_HANDLER(name, var)
+#endif
+
 /*
  * Function prototypes
  */

fs/ext4/ext4_sb.h

@@ -108,12 +108,12 @@ struct ext4_sb_info {
 
 	/* tunables */
 	unsigned long s_stripe;
-	unsigned long s_mb_stream_request;
-	unsigned long s_mb_max_to_scan;
-	unsigned long s_mb_min_to_scan;
-	unsigned long s_mb_stats;
-	unsigned long s_mb_order2_reqs;
-	unsigned long s_mb_group_prealloc;
+	unsigned int s_mb_stream_request;
+	unsigned int s_mb_max_to_scan;
+	unsigned int s_mb_min_to_scan;
+	unsigned int s_mb_stats;
+	unsigned int s_mb_order2_reqs;
+	unsigned int s_mb_group_prealloc;
 	/* where last allocation was done - for stream allocation */
 	unsigned long s_mb_last_group;
 	unsigned long s_mb_last_start;

fs/ext4/mballoc.c

@@ -2721,63 +2721,6 @@ ext4_mb_free_committed_blocks(struct super_block *sb)
 #define EXT4_MB_STREAM_REQ		"stream_req"
 #define EXT4_MB_GROUP_PREALLOC		"group_prealloc"
 
-#define MB_PROC_FOPS(name)					\
-static int ext4_mb_##name##_proc_show(struct seq_file *m, void *v)	\
-{								\
-	struct ext4_sb_info *sbi = m->private;			\
-								\
-	seq_printf(m, "%ld\n", sbi->s_mb_##name);		\
-	return 0;						\
-}								\
-								\
-static int ext4_mb_##name##_proc_open(struct inode *inode, struct file *file)\
-{								\
-	return single_open(file, ext4_mb_##name##_proc_show, PDE(inode)->data);\
-}								\
-								\
-static ssize_t ext4_mb_##name##_proc_write(struct file *file,	\
-		const char __user *buf, size_t cnt, loff_t *ppos)	\
-{								\
-	struct ext4_sb_info *sbi = PDE(file->f_path.dentry->d_inode)->data;\
-	char str[32];						\
-	long value;						\
-	if (cnt >= sizeof(str))					\
-		return -EINVAL;					\
-	if (copy_from_user(str, buf, cnt))			\
-		return -EFAULT;					\
-	value = simple_strtol(str, NULL, 0);			\
-	if (value <= 0)						\
-		return -ERANGE;					\
-	sbi->s_mb_##name = value;				\
-	return cnt;						\
-}								\
-								\
-static const struct file_operations ext4_mb_##name##_proc_fops = {	\
-	.owner		= THIS_MODULE,				\
-	.open		= ext4_mb_##name##_proc_open,		\
-	.read		= seq_read,				\
-	.llseek		= seq_lseek,				\
-	.release	= single_release,			\
-	.write		= ext4_mb_##name##_proc_write,		\
-};
-
-MB_PROC_FOPS(stats);
-MB_PROC_FOPS(max_to_scan);
-MB_PROC_FOPS(min_to_scan);
-MB_PROC_FOPS(order2_reqs);
-MB_PROC_FOPS(stream_request);
-MB_PROC_FOPS(group_prealloc);
-
-#define	MB_PROC_HANDLER(name, var)					\
-do {									\
-	proc = proc_create_data(name, mode, sbi->s_proc,		\
-				&ext4_mb_##var##_proc_fops, sbi);	\
-	if (proc == NULL) {						\
-		printk(KERN_ERR "EXT4-fs: can't to create %s\n", name);	\
-		goto err_out;						\
-	}								\
-} while (0)
-
 static int ext4_mb_init_per_dev_proc(struct super_block *sb)
 {
 	mode_t mode = S_IFREG | S_IRUGO | S_IWUSR;
@@ -2787,12 +2730,12 @@ static int ext4_mb_init_per_dev_proc(struct super_block *sb)
 	if (sbi->s_proc == NULL)
 		return -EINVAL;
 
-	MB_PROC_HANDLER(EXT4_MB_STATS_NAME, stats);
-	MB_PROC_HANDLER(EXT4_MB_MAX_TO_SCAN_NAME, max_to_scan);
-	MB_PROC_HANDLER(EXT4_MB_MIN_TO_SCAN_NAME, min_to_scan);
-	MB_PROC_HANDLER(EXT4_MB_ORDER2_REQ, order2_reqs);
-	MB_PROC_HANDLER(EXT4_MB_STREAM_REQ, stream_request);
-	MB_PROC_HANDLER(EXT4_MB_GROUP_PREALLOC, group_prealloc);
+	EXT4_PROC_HANDLER(EXT4_MB_STATS_NAME, mb_stats);
+	EXT4_PROC_HANDLER(EXT4_MB_MAX_TO_SCAN_NAME, mb_max_to_scan);
+	EXT4_PROC_HANDLER(EXT4_MB_MIN_TO_SCAN_NAME, mb_min_to_scan);
+	EXT4_PROC_HANDLER(EXT4_MB_ORDER2_REQ, mb_order2_reqs);
+	EXT4_PROC_HANDLER(EXT4_MB_STREAM_REQ, mb_stream_request);
+	EXT4_PROC_HANDLER(EXT4_MB_GROUP_PREALLOC, mb_group_prealloc);
 	return 0;
 
 err_out:

fs/ext4/super.c

@@ -3541,6 +3541,48 @@ static int ext4_get_sb(struct file_system_type *fs_type,
 	return get_sb_bdev(fs_type, flags, dev_name, data, ext4_fill_super, mnt);
 }
 
+#ifdef CONFIG_PROC_FS
+static int ext4_ui_proc_show(struct seq_file *m, void *v)
+{
+	unsigned int *p = m->private;
+
+	seq_printf(m, "%u\n", *p);
+	return 0;
+}
+
+static int ext4_ui_proc_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, ext4_ui_proc_show, PDE(inode)->data);
+}
+
+static ssize_t ext4_ui_proc_write(struct file *file, const char __user *buf,
+			       size_t cnt, loff_t *ppos)
+{
+	unsigned int *p = PDE(file->f_path.dentry->d_inode)->data;
+	char str[32];
+	unsigned long value;
+
+	if (cnt >= sizeof(str))
+		return -EINVAL;
+	if (copy_from_user(str, buf, cnt))
+		return -EFAULT;
+	value = simple_strtol(str, NULL, 0);
+	if (value < 0)
+		return -ERANGE;
+	*p = value;
+	return cnt;
+}
+
+const struct file_operations ext4_ui_proc_fops = {
+	.owner		= THIS_MODULE,
+	.open		= ext4_ui_proc_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= single_release,
+	.write		= ext4_ui_proc_write,
+};
+#endif
+
 static struct file_system_type ext4dev_fs_type = {
 	.owner		= THIS_MODULE,
 	.name		= "ext4dev",