proc_fops: convert drivers/isdn/ to seq_file

Convert code away from ->read_proc/->write_proc interfaces.  Switch to
proc_create()/proc_create_data() which make addition of proc entries
reliable wrt NULL ->proc_fops, NULL ->data and so on.

Problem with ->read_proc et al is described here commit
786d7e1612f0b0adb6046f19b906609e4fe8b1ba "Fix rmmod/read/write races in
/proc entries"

[akpm@linux-foundation.org: CONFIG_PROC_FS=n build fix]
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Tilman Schmidt <tilman@imap.cc>
Signed-off-by: Karsten Keil <keil@b1-systems.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 24 insertions, 16 deletions

diff --git a/drivers/isdn/hardware/eicon/capimain.c b/drivers/isdn/hardware/eicon/capimain.c
index 98fcdfc7ca55..0f073cd73763 100644
--- a/drivers/isdn/hardware/eicon/capimain.c
+++ b/drivers/isdn/hardware/eicon/capimain.c
@@ -13,6 +13,7 @@
 #include <linux/module.h>
 #include <linux/init.h>
 #include <asm/uaccess.h>
+#include <linux/seq_file.h>
 #include <linux/skbuff.h>
 
 #include "os_capi.h"
@@ -75,25 +76,32 @@ void diva_os_free_message_buffer(diva_os_message_buffer_s * dmb)
 /*
  * proc function for controller info
  */
-static int diva_ctl_read_proc(char *page, char **start, off_t off,
-			      int count, int *eof, struct capi_ctr *ctrl)
+static int diva_ctl_proc_show(struct seq_file *m, void *v)
 {
+	struct capi_ctr *ctrl = m->private;
 	diva_card *card = (diva_card *) ctrl->driverdata;
-	int len = 0;
-
-	len += sprintf(page + len, "%s\n", ctrl->name);
-	len += sprintf(page + len, "Serial No. : %s\n", ctrl->serial);
-	len += sprintf(page + len, "Id         : %d\n", card->Id);
-	len += sprintf(page + len, "Channels   : %d\n", card->d.channels);
-
-	if (off + count >= len)
-		*eof = 1;
-	if (len < off)
-		return 0;
-	*start = page + off;
-	return ((count < len - off) ? count : len - off);
+
+	seq_printf(m, "%s\n", ctrl->name);
+	seq_printf(m, "Serial No. : %s\n", ctrl->serial);
+	seq_printf(m, "Id         : %d\n", card->Id);
+	seq_printf(m, "Channels   : %d\n", card->d.channels);
+
+	return 0;
+}
+
+static int diva_ctl_proc_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, diva_ctl_proc_show, NULL);
 }
 
+static const struct file_operations diva_ctl_proc_fops = {
+	.owner		= THIS_MODULE,
+	.open		= diva_ctl_proc_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= single_release,
+};
+
 /*
  * set additional os settings in capi_ctr struct
  */
@@ -102,7 +110,7 @@ void diva_os_set_controller_struct(struct capi_ctr *ctrl)
 	ctrl->driver_name = DRIVERLNAME;
 	ctrl->load_firmware = NULL;
 	ctrl->reset_ctr = NULL;
-	ctrl->ctr_read_proc = diva_ctl_read_proc;
+	ctrl->proc_fops = &diva_ctl_proc_fops;
 	ctrl->owner = THIS_MODULE;
 }