proc: switch /proc/cmdline to seq_file

and move it to fs/proc/cmdline.c while I'm at it.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>

1 files changed, 29 insertions, 0 deletions

diff --git a/fs/proc/cmdline.c b/fs/proc/cmdline.c
new file mode 100644
index 000000000000..82676e3fcd1d
--- /dev/null
+++ b/fs/proc/cmdline.c
@@ -0,0 +1,29 @@
+#include <linux/fs.h>
+#include <linux/init.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+
+static int cmdline_proc_show(struct seq_file *m, void *v)
+{
+        seq_printf(m, "%s\n", saved_command_line);
+        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);
+        return 0;
+}
+module_init(proc_cmdline_init);