Rework /proc/locks via seq_files and seq_list helpers

Currently /proc/locks is shown with a proc_read function, but its behavior
is rather complex as it has to manually handle current offset and buffer
length.  On the other hand, files that show objects from lists can be
easily reimplemented using the sequential files and the seq_list_XXX()
helpers.

This saves (as usually) 16 lines of code and more than 200 from
the .text section.

[akpm@linux-foundation.org: no externs in C]
[akpm@linux-foundation.org: warning fixes]
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

1 files changed, 10 insertions, 9 deletions

diff --git a/fs/proc/proc_misc.c b/fs/proc/proc_misc.c
index bee251cb87c8..c9d6d5f400ad 100644
--- a/fs/proc/proc_misc.c
+++ b/fs/proc/proc_misc.c
@@ -66,7 +66,6 @@ extern int get_stram_list(char *);
 extern int get_filesystem_list(char *);
 extern int get_exec_domain_list(char *);
 extern int get_dma_list(char *);
-extern int get_locks_status (char *, char **, off_t, int);
 
 static int proc_calc_metrics(char *page, char **start, off_t off,
                                  int count, int *eof, int len)
@@ -617,16 +616,18 @@ static int cmdline_read_proc(char *page, char **start, off_t off,
         return proc_calc_metrics(page, start, off, count, eof, len);
 }
 
-static int locks_read_proc(char *page, char **start, off_t off,
-                                 int count, int *eof, void *data)
+static int locks_open(struct inode *inode, struct file *filp)
 {
-        int len = get_locks_status(page, start, off, count);
-
-        if (len < count)
-                *eof = 1;
-        return len;
+        return seq_open(filp, &locks_seq_operations);
 }
 
+static const struct file_operations proc_locks_operations = {
+        .open           = locks_open,
+        .read           = seq_read,
+        .llseek         = seq_lseek,
+        .release        = seq_release,
+};
+
 static int execdomains_read_proc(char *page, char **start, off_t off,
                                  int count, int *eof, void *data)
 {
@@ -684,7 +685,6 @@ void __init proc_misc_init(void)
 #endif
                 {"filesystems", filesystems_read_proc},
                 {"cmdline",     cmdline_read_proc},
-                {"locks",       locks_read_proc},
                 {"execdomains", execdomains_read_proc},
                 {NULL,}
         };
@@ -702,6 +702,7 @@ void __init proc_misc_init(void)
                         entry->proc_fops = &proc_kmsg_operations;
         }
 #endif
+        create_seq_entry("locks", 0, &proc_locks_operations);
         create_seq_entry("devices", 0, &proc_devinfo_operations);
         create_seq_entry("cpuinfo", 0, &proc_cpuinfo_operations);
 #ifdef CONFIG_BLOCK