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>

3 files changed, 30 insertions, 10 deletions

diff --git a/fs/proc/Makefile b/fs/proc/Makefile
index 97985c848ac3..48f9f0f121b0 100644
--- a/fs/proc/Makefile
+++ b/fs/proc/Makefile
@@ -9,6 +9,7 @@ proc-$(CONFIG_MMU)	:= mmu.o task_mmu.o
 
 proc-y       += inode.o root.o base.o generic.o array.o \
                 proc_tty.o proc_misc.o
+proc-y  += cmdline.o
 proc-y  += loadavg.o
 proc-y  += meminfo.o
 proc-y  += uptime.o
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);
diff --git a/fs/proc/proc_misc.c b/fs/proc/proc_misc.c
index 9fa20f157cf3..15257d4b1b91 100644
--- a/fs/proc/proc_misc.c
+++ b/fs/proc/proc_misc.c
@@ -472,15 +472,6 @@ static const struct file_operations proc_interrupts_operations = {
         .release        = seq_release,
 };
 
-static int cmdline_read_proc(char *page, char **start, off_t off,
-                                 int count, int *eof, void *data)
-{
-        int len;
-
-        len = sprintf(page, "%s\n", saved_command_line);
-        return proc_calc_metrics(page, start, off, count, eof, len);
-}
-
 #ifdef CONFIG_FILE_LOCKING
 static int locks_open(struct inode *inode, struct file *filp)
 {
@@ -641,7 +632,6 @@ void __init proc_misc_init(void)
                 char *name;
                 int (*read_proc)(char*,char**,off_t,int,int*,void*);
         } *p, simple_ones[] = {
-                {"cmdline",     cmdline_read_proc},
                 {"execdomains", execdomains_read_proc},
                 {NULL,}
         };