proc: introduce proc_create_single{,_data}

Variants of proc_create{,_data} that directly take a seq_file show
callback and drastically reduces the boilerplate code in the callers.

All trivial callers converted over.

Signed-off-by: Christoph Hellwig <hch@lst.de>

16 files changed, 55 insertions, 191 deletions

diff --git a/fs/cifs/cifs_debug.c b/fs/cifs/cifs_debug.c
index 9d69ea433330..4bc4a7ac61d9 100644
--- a/fs/cifs/cifs_debug.c
+++ b/fs/cifs/cifs_debug.c
@@ -314,18 +314,6 @@ skip_rdma:
 	return 0;
 }
 
-static int cifs_debug_data_proc_open(struct inode *inode, struct file *file)
-{
-	return single_open(file, cifs_debug_data_proc_show, NULL);
-}
-
-static const struct file_operations cifs_debug_data_proc_fops = {
-	.open		= cifs_debug_data_proc_open,
-	.read		= seq_read,
-	.llseek		= seq_lseek,
-	.release	= single_release,
-};
-
 #ifdef CONFIG_CIFS_STATS
 static ssize_t cifs_stats_proc_write(struct file *file,
 		const char __user *buffer, size_t count, loff_t *ppos)
@@ -497,7 +485,8 @@ cifs_proc_init(void)
 	if (proc_fs_cifs == NULL)
 		return;
 
-	proc_create("DebugData", 0, proc_fs_cifs, &cifs_debug_data_proc_fops);
+	proc_create_single("DebugData", 0, proc_fs_cifs,
+			cifs_debug_data_proc_show);
 
 #ifdef CONFIG_CIFS_STATS
 	proc_create("Stats", 0, proc_fs_cifs, &cifs_stats_proc_fops);
diff --git a/fs/f2fs/sysfs.c b/fs/f2fs/sysfs.c
index f33a56d6e6dd..4b47ca6296a7 100644
--- a/fs/f2fs/sysfs.c
+++ b/fs/f2fs/sysfs.c
@@ -572,23 +572,6 @@ static int iostat_info_seq_show(struct seq_file *seq, void *offset)
 	return 0;
 }
 
-#define F2FS_PROC_FILE_DEF(_name)					\
-static int _name##_open_fs(struct inode *inode, struct file *file)	\
-{									\
-	return single_open(file, _name##_seq_show, PDE_DATA(inode));	\
-}									\
-									\
-static const struct file_operations f2fs_seq_##_name##_fops = {		\
-	.open = _name##_open_fs,					\
-	.read = seq_read,						\
-	.llseek = seq_lseek,						\
-	.release = single_release,					\
-};
-
-F2FS_PROC_FILE_DEF(segment_info);
-F2FS_PROC_FILE_DEF(segment_bits);
-F2FS_PROC_FILE_DEF(iostat_info);
-
 int __init f2fs_init_sysfs(void)
 {
 	int ret;
@@ -632,12 +615,12 @@ int f2fs_register_sysfs(struct f2fs_sb_info *sbi)
 		sbi->s_proc = proc_mkdir(sb->s_id, f2fs_proc_root);
 
 	if (sbi->s_proc) {
-		proc_create_data("segment_info", S_IRUGO, sbi->s_proc,
-				 &f2fs_seq_segment_info_fops, sb);
-		proc_create_data("segment_bits", S_IRUGO, sbi->s_proc,
-				 &f2fs_seq_segment_bits_fops, sb);
-		proc_create_data("iostat_info", S_IRUGO, sbi->s_proc,
-				&f2fs_seq_iostat_info_fops, sb);
+		proc_create_single_data("segment_info", S_IRUGO, sbi->s_proc,
+				segment_info_seq_show, sb);
+		proc_create_single_data("segment_bits", S_IRUGO, sbi->s_proc,
+				segment_bits_seq_show, sb);
+		proc_create_single_data("iostat_info", S_IRUGO, sbi->s_proc,
+				iostat_info_seq_show, sb);
 	}
 	return 0;
 }
diff --git a/fs/filesystems.c b/fs/filesystems.c
index f2728a4a03a1..b03f57b1105b 100644
--- a/fs/filesystems.c
+++ b/fs/filesystems.c
@@ -238,21 +238,9 @@ static int filesystems_proc_show(struct seq_file *m, void *v)
 	return 0;
 }
 
-static int filesystems_proc_open(struct inode *inode, struct file *file)
-{
-	return single_open(file, filesystems_proc_show, NULL);
-}
-
-static const struct file_operations filesystems_proc_fops = {
-	.open		= filesystems_proc_open,
-	.read		= seq_read,
-	.llseek		= seq_lseek,
-	.release	= single_release,
-};
-
 static int __init proc_filesystems_init(void)
 {
-	proc_create("filesystems", 0, NULL, &filesystems_proc_fops);
+	proc_create_single("filesystems", 0, NULL, filesystems_proc_show);
 	return 0;
 }
 module_init(proc_filesystems_init);
diff --git a/fs/fscache/internal.h b/fs/fscache/internal.h
index 53cfd0b34c38..f83328a7f048 100644
--- a/fs/fscache/internal.h
+++ b/fs/fscache/internal.h
@@ -295,7 +295,7 @@ static inline void fscache_stat_d(atomic_t *stat)
 
 #define __fscache_stat(stat) (stat)
 
-extern const struct file_operations fscache_stats_fops;
+int fscache_stats_show(struct seq_file *m, void *v);
 #else
 
 #define __fscache_stat(stat) (NULL)
diff --git a/fs/fscache/proc.c b/fs/fscache/proc.c
index 459df553ea09..49a8c90414bc 100644
--- a/fs/fscache/proc.c
+++ b/fs/fscache/proc.c
@@ -26,8 +26,8 @@ int __init fscache_proc_init(void)
 		goto error_dir;
 
 #ifdef CONFIG_FSCACHE_STATS
-	if (!proc_create("fs/fscache/stats", S_IFREG | 0444, NULL,
-			 &fscache_stats_fops))
+	if (!proc_create_single("fs/fscache/stats", S_IFREG | 0444, NULL,
+			fscache_stats_show))
 		goto error_stats;
 #endif
 
diff --git a/fs/fscache/stats.c b/fs/fscache/stats.c
index fcc8c2f2690e..00564a1dfd76 100644
--- a/fs/fscache/stats.c
+++ b/fs/fscache/stats.c
@@ -138,7 +138,7 @@ atomic_t fscache_n_cache_culled_objects;
 /*
  * display the general statistics
  */
-static int fscache_stats_show(struct seq_file *m, void *v)
+int fscache_stats_show(struct seq_file *m, void *v)
 {
 	seq_puts(m, "FS-Cache statistics\n");
 
@@ -284,18 +284,3 @@ static int fscache_stats_show(struct seq_file *m, void *v)
 		   atomic_read(&fscache_n_cache_culled_objects));
 	return 0;
 }
-
-/*
- * open "/proc/fs/fscache/stats" allowing provision of a statistical summary
- */
-static int fscache_stats_open(struct inode *inode, struct file *file)
-{
-	return single_open(file, fscache_stats_show, NULL);
-}
-
-const struct file_operations fscache_stats_fops = {
-	.open		= fscache_stats_open,
-	.read		= seq_read,
-	.llseek		= seq_lseek,
-	.release        = single_release,
-};
diff --git a/fs/proc/cmdline.c b/fs/proc/cmdline.c
index 8233e7af9389..fa762c5fbcb2 100644
--- a/fs/proc/cmdline.c
+++ b/fs/proc/cmdline.c
@@ -11,21 +11,9 @@ static int cmdline_proc_show(struct seq_file *m, void *v)
 	return 0;
 }
 
-static int cmdline_proc_open(struct inode *inode, struct file *file)
-{
-	return single_open(file, cmdline_proc_show, NULL);
-}
-
-static const struct file_operations cmdline_proc_fops = {
-	.open		= cmdline_proc_open,
-	.read		= seq_read,
-	.llseek		= seq_lseek,
-	.release	= single_release,
-};
-
 static int __init proc_cmdline_init(void)
 {
-	proc_create("cmdline", 0, NULL, &cmdline_proc_fops);
+	proc_create_single("cmdline", 0, NULL, cmdline_proc_show);
 	return 0;
 }
 fs_initcall(proc_cmdline_init);
diff --git a/fs/proc/generic.c b/fs/proc/generic.c
index f87cb0053387..02bb1914f5f7 100644
--- a/fs/proc/generic.c
+++ b/fs/proc/generic.c
@@ -588,6 +588,35 @@ struct proc_dir_entry *proc_create_seq_private(const char *name, umode_t mode,
 }
 EXPORT_SYMBOL(proc_create_seq_private);
 
+static int proc_single_open(struct inode *inode, struct file *file)
+{
+	struct proc_dir_entry *de = PDE(inode);
+
+	return single_open(file, de->single_show, de->data);
+}
+
+static const struct file_operations proc_single_fops = {
+	.open		= proc_single_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= single_release,
+};
+
+struct proc_dir_entry *proc_create_single_data(const char *name, umode_t mode,
+		struct proc_dir_entry *parent,
+		int (*show)(struct seq_file *, void *), void *data)
+{
+	struct proc_dir_entry *p;
+
+	p = proc_create_reg(name, mode, &parent, data);
+	if (!p)
+		return NULL;
+	p->proc_fops = &proc_single_fops;
+	p->single_show = show;
+	return proc_register(parent, p);
+}
+EXPORT_SYMBOL(proc_create_single_data);
+
 void proc_set_size(struct proc_dir_entry *de, loff_t size)
 {
 	de->size = size;
diff --git a/fs/proc/internal.h b/fs/proc/internal.h
index bcfe830ffd59..84c68508a256 100644
--- a/fs/proc/internal.h
+++ b/fs/proc/internal.h
@@ -44,7 +44,10 @@ struct proc_dir_entry {
 	struct completion *pde_unload_completion;
 	const struct inode_operations *proc_iops;
 	const struct file_operations *proc_fops;
-	const struct seq_operations *seq_ops;
+	union {
+		const struct seq_operations *seq_ops;
+		int (*single_show)(struct seq_file *, void *);
+	};
 	void *data;
 	unsigned int state_size;
 	unsigned int low_ino;
diff --git a/fs/proc/loadavg.c b/fs/proc/loadavg.c
index b572cc865b92..d06694757201 100644
--- a/fs/proc/loadavg.c
+++ b/fs/proc/loadavg.c
@@ -28,21 +28,9 @@ static int loadavg_proc_show(struct seq_file *m, void *v)
 	return 0;
 }
 
-static int loadavg_proc_open(struct inode *inode, struct file *file)
-{
-	return single_open(file, loadavg_proc_show, NULL);
-}
-
-static const struct file_operations loadavg_proc_fops = {
-	.open		= loadavg_proc_open,
-	.read		= seq_read,
-	.llseek		= seq_lseek,
-	.release	= single_release,
-};
-
 static int __init proc_loadavg_init(void)
 {
-	proc_create("loadavg", 0, NULL, &loadavg_proc_fops);
+	proc_create_single("loadavg", 0, NULL, loadavg_proc_show);
 	return 0;
 }
 fs_initcall(proc_loadavg_init);
diff --git a/fs/proc/meminfo.c b/fs/proc/meminfo.c
index 65a72ab57471..2fb04846ed11 100644
--- a/fs/proc/meminfo.c
+++ b/fs/proc/meminfo.c
@@ -149,21 +149,9 @@ static int meminfo_proc_show(struct seq_file *m, void *v)
 	return 0;
 }
 
-static int meminfo_proc_open(struct inode *inode, struct file *file)
-{
-	return single_open(file, meminfo_proc_show, NULL);
-}
-
-static const struct file_operations meminfo_proc_fops = {
-	.open		= meminfo_proc_open,
-	.read		= seq_read,
-	.llseek		= seq_lseek,
-	.release	= single_release,
-};
-
 static int __init proc_meminfo_init(void)
 {
-	proc_create("meminfo", 0, NULL, &meminfo_proc_fops);
+	proc_create_single("meminfo", 0, NULL, meminfo_proc_show);
 	return 0;
 }
 fs_initcall(proc_meminfo_init);
diff --git a/fs/proc/softirqs.c b/fs/proc/softirqs.c
index 24072cc06e65..12901dcf57e2 100644
--- a/fs/proc/softirqs.c
+++ b/fs/proc/softirqs.c
@@ -25,21 +25,9 @@ static int show_softirqs(struct seq_file *p, void *v)
 	return 0;
 }
 
-static int softirqs_open(struct inode *inode, struct file *file)
-{
-	return single_open(file, show_softirqs, NULL);
-}
-
-static const struct file_operations proc_softirqs_operations = {
-	.open		= softirqs_open,
-	.read		= seq_read,
-	.llseek		= seq_lseek,
-	.release	= single_release,
-};
-
 static int __init proc_softirqs_init(void)
 {
-	proc_create("softirqs", 0, NULL, &proc_softirqs_operations);
+	proc_create_single("softirqs", 0, NULL, show_softirqs);
 	return 0;
 }
 fs_initcall(proc_softirqs_init);
diff --git a/fs/proc/uptime.c b/fs/proc/uptime.c
index 95a708d83721..3bd12f955867 100644
--- a/fs/proc/uptime.c
+++ b/fs/proc/uptime.c
@@ -30,21 +30,9 @@ static int uptime_proc_show(struct seq_file *m, void *v)
 	return 0;
 }
 
-static int uptime_proc_open(struct inode *inode, struct file *file)
-{
-	return single_open(file, uptime_proc_show, NULL);
-}
-
-static const struct file_operations uptime_proc_fops = {
-	.open		= uptime_proc_open,
-	.read		= seq_read,
-	.llseek		= seq_lseek,
-	.release	= single_release,
-};
-
 static int __init proc_uptime_init(void)
 {
-	proc_create("uptime", 0, NULL, &uptime_proc_fops);
+	proc_create_single("uptime", 0, NULL, uptime_proc_show);
 	return 0;
 }
 fs_initcall(proc_uptime_init);
diff --git a/fs/proc/version.c b/fs/proc/version.c
index 94901e8e700d..b449f186577f 100644
--- a/fs/proc/version.c
+++ b/fs/proc/version.c
@@ -15,21 +15,9 @@ static int version_proc_show(struct seq_file *m, void *v)
 	return 0;
 }
 
-static int version_proc_open(struct inode *inode, struct file *file)
-{
-	return single_open(file, version_proc_show, NULL);
-}
-
-static const struct file_operations version_proc_fops = {
-	.open		= version_proc_open,
-	.read		= seq_read,
-	.llseek		= seq_lseek,
-	.release	= single_release,
-};
-
 static int __init proc_version_init(void)
 {
-	proc_create("version", 0, NULL, &version_proc_fops);
+	proc_create_single("version", 0, NULL, version_proc_show);
 	return 0;
 }
 fs_initcall(proc_version_init);
diff --git a/fs/reiserfs/procfs.c b/fs/reiserfs/procfs.c
index fe999157dd97..e39b3910d24d 100644
--- a/fs/reiserfs/procfs.c
+++ b/fs/reiserfs/procfs.c
@@ -389,27 +389,13 @@ static int show_journal(struct seq_file *m, void *unused)
 	return 0;
 }
 
-static int r_open(struct inode *inode, struct file *file)
-{
-	return single_open(file, PDE_DATA(inode), 
-				proc_get_parent_data(inode));
-}
-
-static const struct file_operations r_file_operations = {
-	.open = r_open,
-	.read = seq_read,
-	.llseek = seq_lseek,
-	.release = single_release,
-};
-
 static struct proc_dir_entry *proc_info_root = NULL;
 static const char proc_info_root_name[] = "fs/reiserfs";
 
 static void add_file(struct super_block *sb, char *name,
 		     int (*func) (struct seq_file *, void *))
 {
-	proc_create_data(name, 0, REISERFS_SB(sb)->procdir,
-			 &r_file_operations, func);
+	proc_create_single_data(name, 0, REISERFS_SB(sb)->procdir, func, sb);
 }
 
 int reiserfs_proc_info_init(struct super_block *sb)
diff --git a/fs/xfs/xfs_stats.c b/fs/xfs/xfs_stats.c
index 056e12b421eb..04762a72e344 100644
--- a/fs/xfs/xfs_stats.c
+++ b/fs/xfs/xfs_stats.c
@@ -124,18 +124,6 @@ static int xqm_proc_show(struct seq_file *m, void *v)
 	return 0;
 }
 
-static int xqm_proc_open(struct inode *inode, struct file *file)
-{
-	return single_open(file, xqm_proc_show, NULL);
-}
-
-static const struct file_operations xqm_proc_fops = {
-	.open		= xqm_proc_open,
-	.read		= seq_read,
-	.llseek		= seq_lseek,
-	.release	= single_release,
-};
-
 /* legacy quota stats interface no 2 */
 static int xqmstat_proc_show(struct seq_file *m, void *v)
 {
@@ -147,19 +135,6 @@ static int xqmstat_proc_show(struct seq_file *m, void *v)
 	seq_putc(m, '\n');
 	return 0;
 }
-
-static int xqmstat_proc_open(struct inode *inode, struct file *file)
-{
-	return single_open(file, xqmstat_proc_show, NULL);
-}
-
-static const struct file_operations xqmstat_proc_fops = {
-	.owner		= THIS_MODULE,
-	.open		= xqmstat_proc_open,
-	.read		= seq_read,
-	.llseek		= seq_lseek,
-	.release	= single_release,
-};
 #endif /* CONFIG_XFS_QUOTA */
 
 #ifdef CONFIG_PROC_FS
@@ -174,11 +149,9 @@ xfs_init_procfs(void)
 		goto out;
 
 #ifdef CONFIG_XFS_QUOTA
-	if (!proc_create("fs/xfs/xqmstat", 0, NULL,
-			 &xqmstat_proc_fops))
+	if (!proc_create_single("fs/xfs/xqmstat", 0, NULL, xqmstat_proc_show))
 		goto out;
-	if (!proc_create("fs/xfs/xqm", 0, NULL,
-			 &xqm_proc_fops))
+	if (!proc_create_single("fs/xfs/xqm", 0, NULL, xqm_proc_show))
 		goto out;
 #endif
 	return 0;