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, 36 insertions, 39 deletions

diff --git a/drivers/isdn/gigaset/capi.c b/drivers/isdn/gigaset/capi.c
index 3f5cd06af10..6f0ae32906b 100644
--- a/drivers/isdn/gigaset/capi.c
+++ b/drivers/isdn/gigaset/capi.c
@@ -13,6 +13,8 @@
 
 #include "gigaset.h"
 #include <linux/ctype.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
 #include <linux/isdn/capilli.h>
 #include <linux/isdn/capicmd.h>
 #include <linux/isdn/capiutil.h>
@@ -2106,35 +2108,22 @@ static char *gigaset_procinfo(struct capi_ctr *ctr)
 	return ctr->name;	/* ToDo: more? */
 }
 
-/**
- * gigaset_ctr_read_proc() - build controller proc file entry
- * @page:	buffer of PAGE_SIZE bytes for receiving the entry.
- * @start:	unused.
- * @off:	unused.
- * @count:	unused.
- * @eof:	unused.
- * @ctr:	controller descriptor structure.
- *
- * Return value: length of generated entry
- */
-static int gigaset_ctr_read_proc(char *page, char **start, off_t off,
-			  int count, int *eof, struct capi_ctr *ctr)
+static int gigaset_proc_show(struct seq_file *m, void *v)
 {
+	struct capi_ctr *ctr = m->private;
 	struct cardstate *cs = ctr->driverdata;
 	char *s;
 	int i;
-	int len = 0;
-	len += sprintf(page+len, "%-16s %s\n", "name", ctr->name);
-	len += sprintf(page+len, "%-16s %s %s\n", "dev",
+
+	seq_printf(m, "%-16s %s\n", "name", ctr->name);
+	seq_printf(m, "%-16s %s %s\n", "dev",
 			dev_driver_string(cs->dev), dev_name(cs->dev));
-	len += sprintf(page+len, "%-16s %d\n", "id", cs->myid);
+	seq_printf(m, "%-16s %d\n", "id", cs->myid);
 	if (cs->gotfwver)
-		len += sprintf(page+len, "%-16s %d.%d.%d.%d\n", "firmware",
+		seq_printf(m, "%-16s %d.%d.%d.%d\n", "firmware",
 			cs->fwver[0], cs->fwver[1], cs->fwver[2], cs->fwver[3]);
-	len += sprintf(page+len, "%-16s %d\n", "channels",
-			cs->channels);
-	len += sprintf(page+len, "%-16s %s\n", "onechannel",
-			cs->onechannel ? "yes" : "no");
+	seq_printf(m, "%-16s %d\n", "channels", cs->channels);
+	seq_printf(m, "%-16s %s\n", "onechannel", cs->onechannel ? "yes" : "no");
 
 	switch (cs->mode) {
 	case M_UNKNOWN:
@@ -2152,7 +2141,7 @@ static int gigaset_ctr_read_proc(char *page, char **start, off_t off,
 	default:
 		s = "??";
 	}
-	len += sprintf(page+len, "%-16s %s\n", "mode", s);
+	seq_printf(m, "%-16s %s\n", "mode", s);
 
 	switch (cs->mstate) {
 	case MS_UNINITIALIZED:
@@ -2176,25 +2165,21 @@ static int gigaset_ctr_read_proc(char *page, char **start, off_t off,
 	default:
 		s = "??";
 	}
-	len += sprintf(page+len, "%-16s %s\n", "mstate", s);
+	seq_printf(m, "%-16s %s\n", "mstate", s);
 
-	len += sprintf(page+len, "%-16s %s\n", "running",
-			cs->running ? "yes" : "no");
-	len += sprintf(page+len, "%-16s %s\n", "connected",
-			cs->connected ? "yes" : "no");
-	len += sprintf(page+len, "%-16s %s\n", "isdn_up",
-			cs->isdn_up ? "yes" : "no");
-	len += sprintf(page+len, "%-16s %s\n", "cidmode",
-			cs->cidmode ? "yes" : "no");
+	seq_printf(m, "%-16s %s\n", "running", cs->running ? "yes" : "no");
+	seq_printf(m, "%-16s %s\n", "connected", cs->connected ? "yes" : "no");
+	seq_printf(m, "%-16s %s\n", "isdn_up", cs->isdn_up ? "yes" : "no");
+	seq_printf(m, "%-16s %s\n", "cidmode", cs->cidmode ? "yes" : "no");
 
 	for (i = 0; i < cs->channels; i++) {
-		len += sprintf(page+len, "[%d]%-13s %d\n", i, "corrupted",
+		seq_printf(m, "[%d]%-13s %d\n", i, "corrupted",
 				cs->bcs[i].corrupted);
-		len += sprintf(page+len, "[%d]%-13s %d\n", i, "trans_down",
+		seq_printf(m, "[%d]%-13s %d\n", i, "trans_down",
 				cs->bcs[i].trans_down);
-		len += sprintf(page+len, "[%d]%-13s %d\n", i, "trans_up",
+		seq_printf(m, "[%d]%-13s %d\n", i, "trans_up",
 				cs->bcs[i].trans_up);
-		len += sprintf(page+len, "[%d]%-13s %d\n", i, "chstate",
+		seq_printf(m, "[%d]%-13s %d\n", i, "chstate",
 				cs->bcs[i].chstate);
 		switch (cs->bcs[i].proto2) {
 		case L2_BITSYNC:
@@ -2209,11 +2194,23 @@ static int gigaset_ctr_read_proc(char *page, char **start, off_t off,
 		default:
 			s = "??";
 		}
-		len += sprintf(page+len, "[%d]%-13s %s\n", i, "proto2", s);
+		seq_printf(m, "[%d]%-13s %s\n", i, "proto2", s);
 	}
-	return len;
+	return 0;
 }
 
+static int gigaset_proc_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, gigaset_proc_show, PDE(inode)->data);
+}
+
+static const struct file_operations gigaset_proc_fops = {
+	.owner		= THIS_MODULE,
+	.open		= gigaset_proc_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= single_release,
+};
 
 static struct capi_driver capi_driver_gigaset = {
 	.name		= "gigaset",
@@ -2256,7 +2253,7 @@ int gigaset_isdn_register(struct cardstate *cs, const char *isdnid)
 	iif->ctr.release_appl  = gigaset_release_appl;
 	iif->ctr.send_message  = gigaset_send_message;
 	iif->ctr.procinfo      = gigaset_procinfo;
-	iif->ctr.ctr_read_proc = gigaset_ctr_read_proc;
+	iif->ctr.proc_fops = &gigaset_proc_fops;
 	INIT_LIST_HEAD(&iif->appls);
 	skb_queue_head_init(&iif->sendqueue);
 	atomic_set(&iif->sendqlen, 0);