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 3f5cd06af104..6f0ae32906bf 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);