[ATM]: seq_file for /proc/net/atm (devices) [1/8] (from romieu@fr.zoreil.com)

seq_file conversion for proc/atm/devices:
- code inspired from seq_file use in net/core/dev.c;
- atm_dev_lock taken/released in atm_dev_seq_{start/stop};
- add a helper CREATE_SEQ_ENTRY() similar to CREATE_ENTRY() (both are removed
  once conversion is done).
- atm_dev_seq_{start/stop/next} done in net/atm/resource.[ch] to ease
  future handling of atm_devs and locking structure (per Chas suggestion)

diff --git a/net/atm/proc.c b/net/atm/proc.c
index d493ab2cd4203a244d8d91dc745a8cab57c546e1..37a7b5de89f890e6c6bdb0d1f6614da93f561b9b 100644 (file)
--- a/net/atm/proc.c
+++ b/net/atm/proc.c
@@ -24,6 +24,7 @@
 #include <linux/fs.h>
 #include <linux/stat.h>
 #include <linux/proc_fs.h>
+#include <linux/seq_file.h>
 #include <linux/errno.h>
 #include <linux/atm.h>
 #include <linux/atmdev.h>
@@ -64,32 +65,30 @@ static struct file_operations proc_spec_atm_operations = {
        .read =         proc_spec_atm_read,
 };
 
-static void add_stats(char *buf,const char *aal,
+static void add_stats(struct seq_file *seq, const char *aal,
   const struct k_atm_aal_stats *stats)
 {
-       sprintf(strchr(buf,0),"%s ( %d %d %d %d %d )",aal,
+       seq_printf(seq, "%s ( %d %d %d %d %d )", aal,
            atomic_read(&stats->tx),atomic_read(&stats->tx_err),
            atomic_read(&stats->rx),atomic_read(&stats->rx_err),
            atomic_read(&stats->rx_drop));
 }
 
-
-static void atm_dev_info(const struct atm_dev *dev,char *buf)
+static void atm_dev_info(struct seq_file *seq, const struct atm_dev *dev)
 {
-       int off,i;
+       int i;
 
-       off = sprintf(buf,"%3d %-8s",dev->number,dev->type);
+       seq_printf(seq, "%3d %-8s", dev->number, dev->type);
        for (i = 0; i < ESI_LEN; i++)
-               off += sprintf(buf+off,"%02x",dev->esi[i]);
-       strcat(buf,"  ");
-       add_stats(buf,"0",&dev->stats.aal0);
-       strcat(buf,"  ");
-       add_stats(buf,"5",&dev->stats.aal5);
-       sprintf(strchr(buf,0), "\t[%d]", atomic_read(&dev->refcnt));
-       strcat(buf,"\n");
+               seq_printf(seq, "%02x", dev->esi[i]);
+       seq_puts(seq, "  ");
+       add_stats(seq, "0", &dev->stats.aal0);
+       seq_puts(seq, "  ");
+       add_stats(seq, "5", &dev->stats.aal5);
+       seq_printf(seq, "\t[%d]", atomic_read(&dev->refcnt));
+       seq_putc(seq, '\n');
 }
 
-
 #if defined(CONFIG_ATM_CLIP) || defined(CONFIG_ATM_CLIP_MODULE)
 
 
@@ -303,29 +302,40 @@ lec_info(struct lec_arp_table *entry, char *buf)
 
 #endif
 
-static int atm_devices_info(loff_t pos,char *buf)
+static int atm_dev_seq_show(struct seq_file *seq, void *v)
 {
-       struct atm_dev *dev;
-       struct list_head *p;
-       int left;
+       static char atm_dev_banner[] =
+               "Itf Type    ESI/\"MAC\"addr "
+               "AAL(TX,err,RX,err,drop) ...               [refcnt]\n";
+ 
+       if (v == (void *)1)
+               seq_puts(seq, atm_dev_banner);
+       else {
+               struct atm_dev *dev = list_entry(v, struct atm_dev, dev_list);
 
-       if (!pos) {
-               return sprintf(buf,"Itf Type    ESI/\"MAC\"addr "
-                   "AAL(TX,err,RX,err,drop) ...               [refcnt]\n");
-       }
-       left = pos-1;
-       spin_lock(&atm_dev_lock);
-       list_for_each(p, &atm_devs) {
-               dev = list_entry(p, struct atm_dev, dev_list);
-               if (left-- == 0) {
-                       atm_dev_info(dev,buf);
-                       spin_unlock(&atm_dev_lock);
-                       return strlen(buf);
-               }
+               atm_dev_info(seq, dev);
        }
-       spin_unlock(&atm_dev_lock);
-       return 0;
+       return 0;
 }
+ 
+static struct seq_operations atm_dev_seq_ops = {
+       .start  = atm_dev_seq_start,
+       .next   = atm_dev_seq_next,
+       .stop   = atm_dev_seq_stop,
+       .show   = atm_dev_seq_show,
+};
+ 
+static int atm_dev_seq_open(struct inode *inode, struct file *file)
+{
+       return seq_open(file, &atm_dev_seq_ops);
+}
+ 
+static struct file_operations devices_seq_fops = {
+       .open           = atm_dev_seq_open,
+       .read           = seq_read,
+       .llseek         = seq_lseek,
+       .release        = seq_release,
+};
 
 /*
  * FIXME: it isn't safe to walk the VCC list without turning off interrupts.
@@ -630,6 +640,14 @@ void atm_proc_dev_deregister(struct atm_dev *dev)
        kfree(dev->proc_name);
 }
 
+#define CREATE_SEQ_ENTRY(name) \
+       do { \
+               name = create_proc_entry(#name, S_IRUGO, atm_proc_root); \
+               if (!name) \
+                       goto cleanup; \
+               name->proc_fops = & name##_seq_fops; \
+               name->owner = THIS_MODULE; \
+       } while (0)
 
 #define CREATE_ENTRY(name) \
     name = create_proc_entry(#name,0,atm_proc_root); \
@@ -663,7 +681,7 @@ int __init atm_proc_init(void)
        atm_proc_root = proc_mkdir("net/atm",NULL);
        if (!atm_proc_root)
                return -ENOMEM;
-       CREATE_ENTRY(devices);
+       CREATE_SEQ_ENTRY(devices);
        CREATE_ENTRY(pvc);
        CREATE_ENTRY(svc);
        CREATE_ENTRY(vc);

diff --git a/net/atm/resources.c b/net/atm/resources.c
index 732dde666a5558da473d11ea6eaa3ef45399a792..bbae94bd7f207311b050c02555b105c087b4233d 100644 (file)
--- a/net/atm/resources.c
+++ b/net/atm/resources.c
@@ -395,6 +395,35 @@ done:
        return error;
 }
 
+static __inline__ void *dev_get_idx(loff_t left)
+{
+       struct list_head *p;
+
+       list_for_each(p, &atm_devs) {
+               if (!--left)
+                       break;
+       }
+       return (p != &atm_devs) ? p : NULL;
+}
+
+void *atm_dev_seq_start(struct seq_file *seq, loff_t *pos)
+{
+       spin_lock(&atm_dev_lock);
+       return *pos ? dev_get_idx(*pos) : (void *) 1;
+}
+
+void atm_dev_seq_stop(struct seq_file *seq, void *v)
+{
+       spin_unlock(&atm_dev_lock);
+}
+ 
+void *atm_dev_seq_next(struct seq_file *seq, void *v, loff_t *pos)
+{
+       ++*pos;
+       v = (v == (void *)1) ? atm_devs.next : ((struct list_head *)v)->next;
+       return (v == &atm_devs) ? NULL : v;
+}
+
 
 EXPORT_SYMBOL(atm_dev_register);
 EXPORT_SYMBOL(atm_dev_deregister);

diff --git a/net/atm/resources.h b/net/atm/resources.h
index 1b6bad8db9ccba0c1e292484a8c8d2bdf124f05d..5f69a949eebf4cd21c503593b34011c9d5e4e2d1 100644 (file)
--- a/net/atm/resources.h
+++ b/net/atm/resources.h
@@ -21,6 +21,11 @@ int atm_dev_ioctl(unsigned int cmd, unsigned long arg);
 
 #include <linux/proc_fs.h>
 
+void *atm_dev_seq_start(struct seq_file *seq, loff_t *pos);
+void atm_dev_seq_stop(struct seq_file *seq, void *v);
+void *atm_dev_seq_next(struct seq_file *seq, void *v, loff_t *pos);
+
+
 int atm_proc_dev_register(struct atm_dev *dev);
 void atm_proc_dev_deregister(struct atm_dev *dev);