[PATCHKIT] 2.5.74 - seq_file conversion of /proc/net/atm

[PATCHKIT] 2.5.74 - seq_file conversion of /proc/net/atm

[Francois Romieu]

  here comes a first cut at the aforementioned subject. It is divided in
height parts for easier review/integration/flamefest:

1 - devices;
2 - utility and common code for vcs (vc/pvc/svc);
3 - pvc;
4 - svc;
5 - vc;
6 - arp;
7 - lec;
8 - final cleanup.

Each part includes a short description. It is possible to build after
1), 5), 6), 7), 8) (and probably more but it hasn't been tested).

Some testing has been done with a couple of uniprocessor systems:
- 1 behaves well with one or two iphase adapters in the same box;
- 3, 4, 5 doesn't crash and it even seems to display the right number
  of vc. More testing to come;
- same comments apply for 6;
- 7 is completely untested. If somebody has typical scripts at hand for
  a back-to-back lane configuration, he will be welcome.

--
Ueimor

[PATCH 1/8] 2.5.74 - seq_file conversion of /proc/net/atm (devices)

[Francois Romieu]

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_devices_seq_{start/stop};
- add a helper CREATE_SEQ_ENTRY() similar to CREATE_ENTRY() (both are removed
  once conversion is done).


 net/atm/proc.c |  111 ++++++++++++++++++++++++++++++++++++++++-----------------
 1 files changed, 79 insertions(+), 32 deletions(-)

diff -puN net/atm/proc.c~atm-proc-seq-devices net/atm/proc.c
--- linux-2.5.74-1.1360.1.1-to-1.1384/net/atm/proc.c~atm-proc-seq-devices	Tue Jul  8 22:05:57 2003
+++ linux-2.5.74-1.1360.1.1-to-1.1384-fr/net/atm/proc.c	Wed Jul  9 01:41:51 2003
@@ -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_
 	.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)
 
 
@@ -303,30 +302,70 @@ lec_info(struct lec_arp_table *entry, ch
 
 #endif
 
-static int atm_devices_info(loff_t pos,char *buf)
+static __inline__ void *dev_get_idx(struct seq_file *seq, loff_t left)
 {
-	struct atm_dev *dev;
 	struct list_head *p;
-	int left;
 
-	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);
-		}
+		if (!--left)
+			break;
 	}
-	spin_unlock(&atm_dev_lock);
-	return 0;
+	return (p != &atm_devs) ? p : NULL;
+}
+
+static void *atm_devices_seq_start(struct seq_file *seq, loff_t *pos)
+{
+ 	spin_lock(&atm_dev_lock);
+	return *pos ? dev_get_idx(seq, *pos) : (void *) 1;
 }
 
+static void atm_devices_seq_stop(struct seq_file *seq, void *v)
+{
+ 	spin_unlock(&atm_dev_lock);
+}
+ 
+static void *atm_devices_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;
+}
+ 
+static int atm_devices_seq_show(struct seq_file *seq, void *v)
+{
+	static char atm_devices_banner[] =
+		"Itf Type    ESI/\"MAC\"addr "
+		"AAL(TX,err,RX,err,drop) ...               [refcnt]\n";
+ 
+	if (v == (void *)1)
+		seq_puts(seq, atm_devices_banner);
+	else {
+		struct atm_dev *dev = list_entry(v, struct atm_dev, dev_list);
+
+		atm_dev_info(seq, dev);
+	}
+ 	return 0;
+}
+ 
+static struct seq_operations atm_devices_seq_ops = {
+	.start	= atm_devices_seq_start,
+	.next	= atm_devices_seq_next,
+	.stop	= atm_devices_seq_stop,
+	.show	= atm_devices_seq_show,
+};
+ 
+static int atm_devices_seq_open(struct inode *inode, struct file *file)
+{
+	return seq_open(file, &atm_devices_seq_ops);
+}
+ 
+static struct file_operations atm_seq_devices_fops = {
+	.open		= atm_devices_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.
  * What is really needed is some lock on the devices. Ditto for ATMARP.
@@ -623,6 +662,14 @@ void atm_proc_dev_deregister(struct atm_
 	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 = &atm_seq_##name##_fops; \
+		name->owner = THIS_MODULE; \
+	} while (0)
 
 #define CREATE_ENTRY(name) \
     name = create_proc_entry(#name,0,atm_proc_root); \
@@ -656,7 +703,7 @@ 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);

_

[PATCH 2/8] 2.5.74 - seq_file conversion of /proc/net/atm (vc helpers)

[Francois Romieu]

Helpers for seq_file conversion of proc/atm/{pvc/svc/vc}:
- struct atm_vc_state keeps
  1) the struct sock from which the current struct atm_vcc is deduced
  2) the family to which must belong the vcc (PF_ATM{SVC/PVC/any})
  3) the availability of clip module
- atm_vc_common_seq_{start/stop} are responsible for vcc_sklist locking
- atm_vc_common_seq_{open/release} take care of get/put for the clip module.


 net/atm/proc.c |  103 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 files changed, 103 insertions(+)

diff -puN net/atm/proc.c~atm-proc-seq-vc-utils net/atm/proc.c
--- linux-2.5.74-1.1360.1.1-to-1.1384/net/atm/proc.c~atm-proc-seq-vc-utils	Wed Jul  9 01:42:55 2003
+++ linux-2.5.74-1.1360.1.1-to-1.1384-fr/net/atm/proc.c	Wed Jul  9 01:42:55 2003
@@ -161,6 +161,109 @@ static void atmarp_info(struct net_devic
 
 #endif
 
+struct atm_vc_state {
+	struct sock *sk;
+	int family;
+	int clip_info;
+};
+
+static inline int compare_family(struct sock *sk, int family)
+{
+	struct atm_vcc *vcc = atm_sk(sk);
+
+	return !family || (vcc->sk->sk_family == family);
+}
+
+/*
+ * Don't know what happens if l < 1
+ */
+static int __atm_vc_common_walk(struct sock **sock, int family, loff_t l)
+{
+	struct sock *sk = *sock;
+
+	if (sk == (void *)1) {
+		sk = hlist_empty(&vcc_sklist) ? NULL : __sk_head(&vcc_sklist);
+		l--;
+	} 
+	for (; sk; sk = sk_next(sk)) {
+		l -= compare_family(sk, family);
+		if (l < 0)
+			goto out;
+	}
+	sk = (void *)1;
+out:
+	*sock = sk;
+	return (l < 0);
+}
+
+static void *atm_vc_common_walk(struct atm_vc_state *state, loff_t l)
+{
+	return __atm_vc_common_walk(&state->sk, state->family, l) ?
+	       state : NULL;
+}
+
+static int atm_vc_common_seq_open(struct inode *inode, struct file *file,
+	int family, struct seq_operations *ops)
+{
+	struct atm_vc_state *state;
+	struct seq_file *seq;
+	int rc = -ENOMEM;
+
+	state = kmalloc(sizeof(*state), GFP_KERNEL);
+	if (!state)
+		goto out;
+
+	rc = seq_open(file, ops);
+	if (rc)
+		goto out_kfree;
+
+	state->family = family;
+	state->clip_info = try_atm_clip_ops();
+
+	seq = file->private_data;
+	seq->private = state;
+out:
+	return rc;
+out_kfree:
+	kfree(state);
+	goto out;
+}
+
+static int atm_vc_common_seq_release(struct inode *inode, struct file *file)
+{
+#if defined(CONFIG_ATM_CLIP) || defined(CONFIG_ATM_CLIP_MODULE)
+	struct seq_file *seq = file->private_data;
+	struct atm_vc_state *state = seq->private;
+
+	if (state->clip_info)
+		module_put(atm_clip_ops->owner);
+#endif
+	return seq_release_private(inode, file);
+}
+
+static void *atm_vc_common_seq_start(struct seq_file *seq, loff_t *pos)
+{
+	struct atm_vc_state *state = seq->private;
+	loff_t left = *pos;
+
+	read_lock(&vcc_sklist_lock);
+	state->sk = (void *)1;
+	return left ? atm_vc_common_walk(state, left) : (void *)1;
+}
+
+static void atm_vc_common_seq_stop(struct seq_file *seq, void *v)
+{
+	read_unlock(&vcc_sklist_lock);
+}
+
+static void *atm_vc_common_seq_next(struct seq_file *seq, void *v, loff_t *pos)
+{
+	struct atm_vc_state *state = seq->private;
+
+	v = atm_vc_common_walk(state, 1);
+	*pos += !!PTR_ERR(v);
+	return v;
+}
 
 static void pvc_info(struct atm_vcc *vcc, char *buf, int clip_info)
 {

_

[PATCH 3/8] 2.5.74 - seq_file conversion of /proc/net/atm (pvc)

[Francois Romieu]

seq_file support for /proc/net/atm/pvc:
- pvc_info(): seq_printf/seq_putc replaces sprintf;
- atm_pvc_info() removal;
- the vc helpers (atm_vc_common_seq_xxx) do the remaining work.


 net/atm/proc.c |   81 +++++++++++++++++++++++----------------------------------
 1 files changed, 34 insertions(+), 47 deletions(-)

diff -puN net/atm/proc.c~atm-proc-seq-pvc-conversion net/atm/proc.c
--- linux-2.5.74-1.1360.1.1-to-1.1384/net/atm/proc.c~atm-proc-seq-pvc-conversion	Wed Jul  9 01:42:58 2003
+++ linux-2.5.74-1.1360.1.1-to-1.1384-fr/net/atm/proc.c	Wed Jul  9 01:42:58 2003
@@ -265,7 +265,7 @@ static void *atm_vc_common_seq_next(stru
 	return v;
 }
 
-static void pvc_info(struct atm_vcc *vcc, char *buf, int clip_info)
+static void pvc_info(struct seq_file *seq, struct atm_vcc *vcc, int clip_info)
 {
 	static const char *class_name[] = { "off","UBR","CBR","VBR","ABR" };
 	static const char *aal_name[] = {
@@ -273,9 +273,8 @@ static void pvc_info(struct atm_vcc *vcc
 		"???",	"5",	"???",	"???",	/*  4- 7 */
 		"???",	"???",	"???",	"???",	/*  8-11 */
 		"???",	"0",	"???",	"???"};	/* 12-15 */
-	int off;
 
-	off = sprintf(buf,"%3d %3d %5d %-3s %7d %-5s %7d %-6s",
+	seq_printf(seq, "%3d %3d %5d %-3s %7d %-5s %7d %-6s",
 	    vcc->dev->number,vcc->vpi,vcc->vci,
 	    vcc->qos.aal >= sizeof(aal_name)/sizeof(aal_name[0]) ? "err" :
 	    aal_name[vcc->qos.aal],vcc->qos.rxtp.min_pcr,
@@ -287,18 +286,14 @@ static void pvc_info(struct atm_vcc *vcc
 		struct net_device *dev;
 
 		dev = clip_vcc->entry ? clip_vcc->entry->neigh->dev : NULL;
-		off += sprintf(buf+off,"CLIP, Itf:%s, Encap:",
+		seq_printf(seq, "CLIP, Itf:%s, Encap:",
 		    dev ? dev->name : "none?");
-		if (clip_vcc->encap)
-			off += sprintf(buf+off,"LLC/SNAP");
-		else
-			off += sprintf(buf+off,"None");
+		seq_printf(seq, "%s", clip_vcc->encap ? "LLC/SNAP" : "None");
 	}
 #endif
-	strcpy(buf+off,"\n");
+	seq_putc(seq, '\n');
 }
 
-
 static const char *vcc_state(struct atm_vcc *vcc)
 {
 	static const char *map[] = { ATM_VS2TXT_MAP };
@@ -469,48 +464,40 @@ static struct file_operations atm_seq_de
 	.release	= seq_release,
 };
 
-/*
- * FIXME: it isn't safe to walk the VCC list without turning off interrupts.
- * What is really needed is some lock on the devices. Ditto for ATMARP.
- */
-
-static int atm_pvc_info(loff_t pos,char *buf)
+static int atm_pvc_seq_show(struct seq_file *seq, void *v)
 {
-	struct hlist_node *node;
-	struct sock *s;
-	struct atm_vcc *vcc;
-	int left, clip_info = 0;
+	static char atm_pvc_banner[] = 
+		"Itf VPI VCI   AAL RX(PCR,Class) TX(PCR,Class)\n";
 
-	if (!pos) {
-		return sprintf(buf,"Itf VPI VCI   AAL RX(PCR,Class) "
-		    "TX(PCR,Class)\n");
-	}
-	left = pos-1;
-#if defined(CONFIG_ATM_CLIP) || defined(CONFIG_ATM_CLIP_MODULE)
-	if (try_atm_clip_ops())
-		clip_info = 1;
-#endif
-	read_lock(&vcc_sklist_lock);
-	sk_for_each(s, node, &vcc_sklist) {
-		vcc = atm_sk(s);
-		if (vcc->sk->sk_family == PF_ATMPVC && vcc->dev && !left--) {
-			pvc_info(vcc,buf,clip_info);
-			read_unlock(&vcc_sklist_lock);
-#if defined(CONFIG_ATM_CLIP) || defined(CONFIG_ATM_CLIP_MODULE)
-			if (clip_info)
-				module_put(atm_clip_ops->owner);
-#endif
-			return strlen(buf);
-		}
+	if (v == (void *)1)
+		seq_puts(seq, atm_pvc_banner);
+	else {
+		struct atm_vc_state *state = seq->private;
+		struct atm_vcc *vcc = atm_sk(state->sk);
+
+		pvc_info(seq, vcc, state->clip_info);
 	}
-	read_unlock(&vcc_sklist_lock);
-#if defined(CONFIG_ATM_CLIP) || defined(CONFIG_ATM_CLIP_MODULE)
-	if (clip_info)
-		module_put(atm_clip_ops->owner);
-#endif
 	return 0;
 }
 
+static struct seq_operations atm_pvc_seq_ops = {
+	.start	= atm_vc_common_seq_start,
+	.next	= atm_vc_common_seq_next,
+	.stop	= atm_vc_common_seq_stop,
+	.show	= atm_pvc_seq_show,
+};
+
+static int atm_pvc_seq_open(struct inode *inode, struct file *file)
+{
+	return atm_vc_common_seq_open(inode, file, PF_ATMPVC, &atm_pvc_seq_ops);
+}
+
+static struct file_operations atm_seq_pvc_fops = {
+	.open		= atm_pvc_seq_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= atm_vc_common_seq_release,
+};
 
 static int atm_vc_info(loff_t pos,char *buf)
 {
@@ -807,7 +794,7 @@ int __init atm_proc_init(void)
 	if (!atm_proc_root)
 		return -ENOMEM;
 	CREATE_SEQ_ENTRY(devices);
-	CREATE_ENTRY(pvc);
+	CREATE_SEQ_ENTRY(pvc);
 	CREATE_ENTRY(svc);
 	CREATE_ENTRY(vc);
 #if defined(CONFIG_ATM_CLIP) || defined(CONFIG_ATM_CLIP_MODULE)

_

[PATCH 4/8] 2.5.74 - seq_file conversion of /proc/net/atm (svc)

[Francois Romieu]

seq_file support for /proc/net/atm/svc:

Same comments as pvc. Just s/p/s/


 net/atm/proc.c |   81 ++++++++++++++++++++++++++++++---------------------------
 1 files changed, 44 insertions(+), 37 deletions(-)

diff -puN net/atm/proc.c~atm-proc-seq-svc-conversion net/atm/proc.c
--- linux-2.5.74-1.1360.1.1-to-1.1384/net/atm/proc.c~atm-proc-seq-svc-conversion	Wed Jul  9 01:42:59 2003
+++ linux-2.5.74-1.1360.1.1-to-1.1384-fr/net/atm/proc.c	Wed Jul  9 01:42:59 2003
@@ -326,29 +326,26 @@ static void vc_info(struct atm_vcc *vcc,
 	    atomic_read(&vcc->sk->sk_rmem_alloc), vcc->sk->sk_rcvbuf);
 }
 
-
-static void svc_info(struct atm_vcc *vcc,char *buf)
+static void svc_info(struct seq_file *seq, struct atm_vcc *vcc)
 {
-	char *here;
-	int i;
-
 	if (!vcc->dev)
-		sprintf(buf,sizeof(void *) == 4 ? "N/A@%p%10s" : "N/A@%p%2s",
-		    vcc,"");
-	else sprintf(buf,"%3d %3d %5d         ",vcc->dev->number,vcc->vpi,
-		    vcc->vci);
-	here = strchr(buf,0);
-	here += sprintf(here,"%-10s ",vcc_state(vcc));
-	here += sprintf(here,"%s%s",vcc->remote.sas_addr.pub,
+		seq_printf(seq, sizeof(void *) == 4 ?
+			   "N/A@%p%10s" : "N/A@%p%2s", vcc, "");
+	else
+		seq_printf(seq, "%3d %3d %5d         ",
+			   vcc->dev->number, vcc->vpi, vcc->vci);
+	seq_printf(seq, "%-10s ", vcc_state(vcc));
+	seq_printf(seq, "%s%s", vcc->remote.sas_addr.pub,
 	    *vcc->remote.sas_addr.pub && *vcc->remote.sas_addr.prv ? "+" : "");
-	if (*vcc->remote.sas_addr.prv)
+	if (*vcc->remote.sas_addr.prv) {
+		int i;
+
 		for (i = 0; i < ATM_ESA_LEN; i++)
-			here += sprintf(here,"%02x",
-			    vcc->remote.sas_addr.prv[i]);
-	strcat(here,"\n");
+			seq_printf(seq, "%02x", vcc->remote.sas_addr.prv[i]);
+	}
+	seq_putc(seq, '\n');
 }
 
-
 #if defined(CONFIG_ATM_LANE) || defined(CONFIG_ATM_LANE_MODULE)
 
 static char*
@@ -525,31 +522,41 @@ static int atm_vc_info(loff_t pos,char *
 	return 0;
 }
 
-
-static int atm_svc_info(loff_t pos,char *buf)
+static int atm_svc_seq_show(struct seq_file *seq, void *v)
 {
-	struct hlist_node *node;
-	struct sock *s;
-	struct atm_vcc *vcc;
-	int left;
+	static char atm_svc_banner[] = 
+		"Itf VPI VCI           State      Remote\n";
 
-	if (!pos)
-		return sprintf(buf,"Itf VPI VCI           State      Remote\n");
-	left = pos-1;
-	read_lock(&vcc_sklist_lock);
-	sk_for_each(s, node, &vcc_sklist) {
-		vcc = atm_sk(s);
-		if (vcc->sk->sk_family == PF_ATMSVC && !left--) {
-			svc_info(vcc,buf);
-			read_unlock(&vcc_sklist_lock);
-			return strlen(buf);
-		}
-	}
-	read_unlock(&vcc_sklist_lock);
+	if (v == (void *)1)
+		seq_puts(seq, atm_svc_banner);
+	else {
+		struct atm_vc_state *state = seq->private;
+		struct atm_vcc *vcc = atm_sk(state->sk);
 
+		svc_info(seq, vcc);
+	}
 	return 0;
 }
 
+static struct seq_operations atm_svc_seq_ops = {
+	.start	= atm_vc_common_seq_start,
+	.next	= atm_vc_common_seq_next,
+	.stop	= atm_vc_common_seq_stop,
+	.show	= atm_svc_seq_show,
+};
+
+static int atm_svc_seq_open(struct inode *inode, struct file *file)
+{
+	return atm_vc_common_seq_open(inode, file, PF_ATMSVC, &atm_svc_seq_ops);
+}
+
+static struct file_operations atm_seq_svc_fops = {
+	.open		= atm_svc_seq_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= atm_vc_common_seq_release,
+};
+
 #if defined(CONFIG_ATM_CLIP) || defined(CONFIG_ATM_CLIP_MODULE)
 static int atm_arp_info(loff_t pos,char *buf)
 {
@@ -795,7 +802,7 @@ int __init atm_proc_init(void)
 		return -ENOMEM;
 	CREATE_SEQ_ENTRY(devices);
 	CREATE_SEQ_ENTRY(pvc);
-	CREATE_ENTRY(svc);
+	CREATE_SEQ_ENTRY(svc);
 	CREATE_ENTRY(vc);
 #if defined(CONFIG_ATM_CLIP) || defined(CONFIG_ATM_CLIP_MODULE)
 	CREATE_ENTRY(arp);

_

[PATCH 5/8] 2.5.74 - seq_file conversion of /proc/net/atm (vc)

[Francois Romieu]

seq_file support for /proc/net/atm/vc:

Same comments as for pvc and svc.


 net/atm/proc.c |   80 ++++++++++++++++++++++++++++++---------------------------
 1 files changed, 43 insertions(+), 37 deletions(-)

diff -puN net/atm/proc.c~atm-proc-seq-vc-conversion net/atm/proc.c
--- linux-2.5.74-1.1360.1.1-to-1.1384/net/atm/proc.c~atm-proc-seq-vc-conversion	Wed Jul  9 01:43:00 2003
+++ linux-2.5.74-1.1360.1.1-to-1.1384-fr/net/atm/proc.c	Wed Jul  9 01:43:00 2003
@@ -301,29 +301,27 @@ static const char *vcc_state(struct atm_
 	return map[ATM_VF2VS(vcc->flags)];
 }
 
-
-static void vc_info(struct atm_vcc *vcc,char *buf)
+static void vc_info(struct seq_file *seq, struct atm_vcc *vcc)
 {
-	char *here;
-
-	here = buf+sprintf(buf,"%p ",vcc);
-	if (!vcc->dev) here += sprintf(here,"Unassigned    ");
-	else here += sprintf(here,"%3d %3d %5d ",vcc->dev->number,vcc->vpi,
-		    vcc->vci);
+	seq_printf(seq, "%p ", vcc);
+	if (!vcc->dev)
+		seq_printf(seq, "Unassigned    ");
+	else 
+		seq_printf(seq, "%3d %3d %5d ", vcc->dev->number, vcc->vpi,
+			vcc->vci);
 	switch (vcc->sk->sk_family) {
 		case AF_ATMPVC:
-			here += sprintf(here,"PVC");
+			seq_printf(seq, "PVC");
 			break;
 		case AF_ATMSVC:
-			here += sprintf(here,"SVC");
+			seq_printf(seq, "SVC");
 			break;
 		default:
-			here += sprintf(here, "%3d", vcc->sk->sk_family);
+			seq_printf(seq, "%3d", vcc->sk->sk_family);
 	}
-	here += sprintf(here," %04lx  %5d %7d/%7d %7d/%7d\n",vcc->flags,
-	    vcc->reply,
-	    atomic_read(&vcc->sk->sk_wmem_alloc), vcc->sk->sk_sndbuf,
-	    atomic_read(&vcc->sk->sk_rmem_alloc), vcc->sk->sk_rcvbuf);
+	seq_printf(seq, " %04lx  %5d %7d/%7d %7d/%7d\n", vcc->flags, vcc->reply,
+		atomic_read(&vcc->sk->sk_wmem_alloc),vcc->sk->sk_sndbuf,
+		atomic_read(&vcc->sk->sk_rmem_alloc),vcc->sk->sk_rcvbuf);
 }
 
 static void svc_info(struct seq_file *seq, struct atm_vcc *vcc)
@@ -496,32 +494,33 @@ static struct file_operations atm_seq_pv
 	.release	= atm_vc_common_seq_release,
 };
 
-static int atm_vc_info(loff_t pos,char *buf)
+static int atm_vc_seq_show(struct seq_file *seq, void *v)
 {
-	struct atm_vcc *vcc;
-	struct hlist_node *node;
-	struct sock *s;
-	int left;
-
-	if (!pos)
-		return sprintf(buf,sizeof(void *) == 4 ? "%-8s%s" : "%-16s%s",
-		    "Address"," Itf VPI VCI   Fam Flags Reply Send buffer"
-		    "     Recv buffer\n");
-	left = pos-1;
-	read_lock(&vcc_sklist_lock);
-	sk_for_each(s, node, &vcc_sklist) {
-		vcc = atm_sk(s);
-		if (!left--) {
-			vc_info(vcc,buf);
-			read_unlock(&vcc_sklist_lock);
-			return strlen(buf);
-		}
-	}
-	read_unlock(&vcc_sklist_lock);
+	if (v == (void *)1) {
+		seq_printf(seq, sizeof(void *) == 4 ? "%-8s%s" : "%-16s%s",
+			"Address ", "Itf VPI VCI   Fam Flags Reply "
+			"Send buffer     Recv buffer\n");
+	} else {
+		struct atm_vc_state *state = seq->private;
+		struct atm_vcc *vcc = atm_sk(state->sk);
 
+		vc_info(seq, vcc);
+	}
 	return 0;
 }
 
+static struct seq_operations atm_vc_seq_ops = {
+	.start	= atm_vc_common_seq_start,
+	.next	= atm_vc_common_seq_next,
+	.stop	= atm_vc_common_seq_stop,
+	.show	= atm_vc_seq_show,
+};
+
+static int atm_vc_seq_open(struct inode *inode, struct file *file)
+{
+	return atm_vc_common_seq_open(inode, file, 0, &atm_vc_seq_ops);
+}
+
 static int atm_svc_seq_show(struct seq_file *seq, void *v)
 {
 	static char atm_svc_banner[] = 
@@ -538,6 +537,13 @@ static int atm_svc_seq_show(struct seq_f
 	return 0;
 }
 
+static struct file_operations atm_seq_vc_fops = {
+	.open		= atm_vc_seq_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= atm_vc_common_seq_release,
+};
+
 static struct seq_operations atm_svc_seq_ops = {
 	.start	= atm_vc_common_seq_start,
 	.next	= atm_vc_common_seq_next,
@@ -803,7 +809,7 @@ int __init atm_proc_init(void)
 	CREATE_SEQ_ENTRY(devices);
 	CREATE_SEQ_ENTRY(pvc);
 	CREATE_SEQ_ENTRY(svc);
-	CREATE_ENTRY(vc);
+	CREATE_SEQ_ENTRY(vc);
 #if defined(CONFIG_ATM_CLIP) || defined(CONFIG_ATM_CLIP_MODULE)
 	CREATE_ENTRY(arp);
 #endif

_

seq_file and proc_dir_entry data (was Re: [PATCH 5/8] 2.5.74 - seq_file conversion of /proc/net/atm (vc))

[Ed L Cashin]

On creating a proc entry, it's possible to set the data field to an
arbitrary pointer value.  Later, that pointer value can be used in
callbacks to do interesting things, like access persistent data
associated with the proc file.

I had to rewrite seq_read so that when it calls the start operation it
passes a pointer to a struct (not an loff_t) with iterator info and
also a pointer to the proc_dir_entry data field.

Would it be possible to modify seq_file to give easier access to the
data field of proc_dir_entry, or is seq_file too general for that to
be practical?

-- 
--Ed L Cashin            |   PGP public key:
  ecashin@uga.edu        |   http://noserose.net/e/pgp/

[PATCH 6/8] 2.5.74 - seq_file conversion of /proc/net/atm (arp)

[Francois Romieu]

seq_file support for /proc/net/atm/arp:
- svc_addr/atmarp_info(): seq_printf/seq_putc replace sprintf and friends;
- atm_arp_getidx/atm_arp_vc_walk() take care of the usual seq_file cursor
  positionning: they both return NULL until the cursor has reached its
  position. struct atm_arp_state is updated accordingly;
- atm_arp_seq_{stop/start} are responsible for clip_tbl_hook (un)locking;
- module refcounting is done in atm_arp_seq_open()/atm_arp_seq_release();
- atm_lec_info() is removed.


 net/atm/proc.c |  269 +++++++++++++++++++++++++++++++++++++++------------------
 1 files changed, 185 insertions(+), 84 deletions(-)

diff -puN net/atm/proc.c~atm-proc-seq-arp-conversion net/atm/proc.c
--- linux-2.5.74-1.1360.1.1-to-1.1384/net/atm/proc.c~atm-proc-seq-arp-conversion	Wed Jul  9 01:43:02 2003
+++ linux-2.5.74-1.1360.1.1-to-1.1384-fr/net/atm/proc.c	Wed Jul  9 01:43:02 2003
@@ -91,75 +91,67 @@ static void atm_dev_info(struct seq_file
 
 #if defined(CONFIG_ATM_CLIP) || defined(CONFIG_ATM_CLIP_MODULE)
 
-
-static int svc_addr(char *buf,struct sockaddr_atmsvc *addr)
+static void svc_addr(struct seq_file *seq, struct sockaddr_atmsvc *addr)
 {
 	static int code[] = { 1,2,10,6,1,0 };
 	static int e164[] = { 1,8,4,6,1,0 };
-	int *fields;
-	int len,i,j,pos;
 
-	len = 0;
 	if (*addr->sas_addr.pub) {
-		strcpy(buf,addr->sas_addr.pub);
-		len = strlen(addr->sas_addr.pub);
-		buf += len;
-		if (*addr->sas_addr.prv) {
-			*buf++ = '+';
-			len++;
-		}
+		seq_printf(seq, "%s", addr->sas_addr.pub);
+		if (*addr->sas_addr.prv)
+			seq_putc(seq, '+');
+	} else if (!*addr->sas_addr.prv) {
+		seq_printf(seq, "%s", "(none)");
+		return;
 	}
-	else if (!*addr->sas_addr.prv) {
-			strcpy(buf,"(none)");
-			return strlen(buf);
-		}
 	if (*addr->sas_addr.prv) {
-		len += 44;
-		pos = 0;
-		fields = *addr->sas_addr.prv == ATM_AFI_E164 ? e164 : code;
+		unsigned char *prv = addr->sas_addr.prv;
+		int *fields;
+		int i, j;
+
+		fields = *prv == ATM_AFI_E164 ? e164 : code;
 		for (i = 0; fields[i]; i++) {
-			for (j = fields[i]; j; j--) {
-				sprintf(buf,"%02X",addr->sas_addr.prv[pos++]);
-				buf += 2;
-			}
-			if (fields[i+1]) *buf++ = '.';
+			for (j = fields[i]; j; j--)
+				seq_printf(seq, "%02X", *prv++);
+			if (fields[i+1])
+				seq_putc(seq, '.');
 		}
 	}
-	return len;
 }
 
-
-static void atmarp_info(struct net_device *dev,struct atmarp_entry *entry,
-    struct clip_vcc *clip_vcc,char *buf)
+static void atmarp_info(struct seq_file *seq, struct net_device *dev,
+			struct atmarp_entry *entry, struct clip_vcc *clip_vcc)
 {
-	unsigned char *ip;
-	int svc,off,ip_len;
+	char buf[17];
+	int svc, off;
 
 	svc = !clip_vcc || clip_vcc->vcc->sk->sk_family == AF_ATMSVC;
-	off = sprintf(buf,"%-6s%-4s%-4s%5ld ",dev->name,svc ? "SVC" : "PVC",
+	seq_printf(seq, "%-6s%-4s%-4s%5ld ", dev->name, svc ? "SVC" : "PVC",
 	    !clip_vcc || clip_vcc->encap ? "LLC" : "NULL",
-	    (jiffies-(clip_vcc ? clip_vcc->last_use : entry->neigh->used))/
-	    HZ);
-	ip = (unsigned char *) &entry->ip;
-	ip_len = sprintf(buf+off,"%d.%d.%d.%d",ip[0],ip[1],ip[2],ip[3]);
-	off += ip_len;
-	while (ip_len++ < 16) buf[off++] = ' ';
-	if (!clip_vcc)
+	    (jiffies-(clip_vcc ? clip_vcc->last_use : entry->neigh->used))/HZ);
+
+	off = snprintf(buf, sizeof(buf) - 1, "%d.%d.%d.%d", NIPQUAD(entry->ip));
+	while (off < 16)
+		buf[off++] = ' ';
+	buf[off] = '\0';
+	seq_printf(seq, "%s", buf);
+
+	if (!clip_vcc) {
 		if (time_before(jiffies, entry->expires))
-			strcpy(buf+off,"(resolving)\n");
-		else sprintf(buf+off,"(expired, ref %d)\n",
-			    atomic_read(&entry->neigh->refcnt));
-	else if (!svc)
-			sprintf(buf+off,"%d.%d.%d\n",clip_vcc->vcc->dev->number,
-			    clip_vcc->vcc->vpi,clip_vcc->vcc->vci);
-		else {
-			off += svc_addr(buf+off,&clip_vcc->vcc->remote);
-			strcpy(buf+off,"\n");
-		}
+			seq_printf(seq, "(resolving)\n");
+		else
+			seq_printf(seq, "(expired, ref %d)\n",
+				   atomic_read(&entry->neigh->refcnt));
+	} else if (!svc) {
+		seq_printf(seq, "%d.%d.%d\n", clip_vcc->vcc->dev->number,
+			   clip_vcc->vcc->vpi, clip_vcc->vcc->vci);
+	} else {
+		svc_addr(seq, &clip_vcc->vcc->remote);
+		seq_putc(seq, '\n');
+	}
 }
 
-
-#endif
+#endif /* CONFIG_ATM_CLIP */
 
 struct atm_vc_state {
 	struct sock *sk;
@@ -564,45 +556,154 @@ static struct file_operations atm_seq_sv
 };
 
 #if defined(CONFIG_ATM_CLIP) || defined(CONFIG_ATM_CLIP_MODULE)
-static int atm_arp_info(loff_t pos,char *buf)
+
+struct atm_arp_state {
+	int bucket;
+  	struct neighbour *n;
+	struct clip_vcc *vcc;
+};
+  
+static void *atm_arp_vc_walk(struct atm_arp_state *state,
+			     struct atmarp_entry *e, loff_t *l)
+{
+	struct clip_vcc *vcc = state->vcc;
+
+	if (!vcc)
+		vcc = e->vccs;
+	if (vcc == (void *)1) {
+		vcc = e->vccs;
+		--*l;
+  	}
+	for (; vcc; vcc = vcc->next) {
+		if (--*l < 0)
+			break;
+	}
+	state->vcc = vcc;
+	return (*l < 0) ? state : NULL;
+}
+  
+static void *atm_arp_get_idx(struct atm_arp_state *state, loff_t l)
 {
-	struct neighbour *n;
-	int i,count;
+	void *v = NULL;
 
-	if (!pos) {
-		return sprintf(buf,"IPitf TypeEncp Idle IP address      "
-		    "ATM address\n");
+	for (; state->bucket <= NEIGH_HASHMASK; state->bucket++) {
+		for (; state->n; state->n = state->n->next) {
+			v = atm_arp_vc_walk(state, NEIGH2ENTRY(state->n), &l);
+			if (v)
+				goto done;
+  		}
+		state->n = clip_tbl_hook->hash_buckets[state->bucket + 1];
 	}
-	if (!try_atm_clip_ops())
-		return 0;
-	count = pos;
+done:
+	return v;
+}
+
+static void *atm_arp_seq_start(struct seq_file *seq, loff_t *pos)
+{
+	struct atm_arp_state *state = seq->private;
+	void *ret = (void *)1;
+
+	if (!clip_tbl_hook) {
+		state->bucket = -1;
+		goto out;
+	}
+
 	read_lock_bh(&clip_tbl_hook->lock);
-	for (i = 0; i <= NEIGH_HASHMASK; i++)
-		for (n = clip_tbl_hook->hash_buckets[i]; n; n = n->next) {
-			struct atmarp_entry *entry = NEIGH2ENTRY(n);
-			struct clip_vcc *vcc;
-
-			if (!entry->vccs) {
-				if (--count) continue;
-				atmarp_info(n->dev,entry,NULL,buf);
-				read_unlock_bh(&clip_tbl_hook->lock);
-				module_put(atm_clip_ops->owner);
-				return strlen(buf);
-			}
-			for (vcc = entry->vccs; vcc;
-			    vcc = vcc->next) {
-				if (--count) continue;
-				atmarp_info(n->dev,entry,vcc,buf);
-				read_unlock_bh(&clip_tbl_hook->lock);
-				module_put(atm_clip_ops->owner);
-				return strlen(buf);
-			}
-		}
-	read_unlock_bh(&clip_tbl_hook->lock);
+	state->bucket = 0;
+	state->n = clip_tbl_hook->hash_buckets[0];
+	state->vcc = (void *)1;
+	if (*pos)
+		ret = atm_arp_get_idx(state, *pos);
+out:
+	return ret;
+}
+
+static void atm_arp_seq_stop(struct seq_file *seq, void *v)
+{
+	struct atm_arp_state *state = seq->private;
+
+	if (state->bucket != -1)
+		read_unlock_bh(&clip_tbl_hook->lock);
+}
+
+static void *atm_arp_seq_next(struct seq_file *seq, void *v, loff_t *pos)
+{
+	struct atm_arp_state *state = seq->private;
+
+	v = atm_arp_get_idx(state, 1);
+	*pos += !!PTR_ERR(v);
+	return v;
+}
+
+static int atm_arp_seq_show(struct seq_file *seq, void *v)
+{
+	static char atm_arp_banner[] = 
+		"IPitf TypeEncp Idle IP address      ATM address\n";
+
+	if (v == (void *)1)
+		seq_puts(seq, atm_arp_banner);
+	else {
+		struct atm_arp_state *state = seq->private;
+		struct neighbour *n = state->n;	
+		struct clip_vcc *vcc = state->vcc;
+
+		atmarp_info(seq, n->dev, NEIGH2ENTRY(n), vcc);
+	}
+  	return 0;
+}
+
+static struct seq_operations atm_arp_seq_ops = {
+	.start	= atm_arp_seq_start,
+	.next	= atm_arp_seq_next,
+	.stop	= atm_arp_seq_stop,
+	.show	= atm_arp_seq_show,
+};
+
+static int atm_arp_seq_open(struct inode *inode, struct file *file)
+{
+	struct atm_arp_state *state;
+	struct seq_file *seq;
+	int rc = -EAGAIN;
+
+	if (!try_atm_clip_ops())
+		goto out;
+
+	state = kmalloc(sizeof(*state), GFP_KERNEL);
+	if (!state) {
+		rc = -ENOMEM;
+		goto out_put;
+	}
+
+	rc = seq_open(file, &atm_arp_seq_ops);
+	if (rc)
+		goto out_kfree;
+
+	seq = file->private_data;
+	seq->private = state;
+out:
+	return rc;
+
+out_put:
 	module_put(atm_clip_ops->owner);
-	return 0;
+out_kfree:
+	kfree(state);
+	goto out;
 }
-#endif
+
+static int atm_arp_seq_release(struct inode *inode, struct file *file)
+{
+	module_put(atm_clip_ops->owner);
+	return seq_release_private(inode, file);
+}
+
+static struct file_operations atm_seq_arp_fops = {
+	.open		= atm_arp_seq_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= atm_arp_seq_release,
+};
+
+#endif /* CONFIG_ATM_CLIP */
 
 #if defined(CONFIG_ATM_LANE) || defined(CONFIG_ATM_LANE_MODULE)
 static int atm_lec_info(loff_t pos,char *buf)
@@ -811,7 +912,7 @@ int __init atm_proc_init(void)
 	CREATE_SEQ_ENTRY(svc);
 	CREATE_SEQ_ENTRY(vc);
 #if defined(CONFIG_ATM_CLIP) || defined(CONFIG_ATM_CLIP_MODULE)
-	CREATE_ENTRY(arp);
+	CREATE_SEQ_ENTRY(arp);
 #endif
 #if defined(CONFIG_ATM_LANE) || defined(CONFIG_ATM_LANE_MODULE)
 	CREATE_ENTRY(lec);

_

[PATCH 7/8] 2.5.74 - seq_file conversion of /proc/net/atm (lec)

[Francois Romieu]

seq_file support for /proc/net/atm/lec:
- lec_info(): seq_printf/seq_putc replaces sprintf;
- traversal of the lec structure needs to walk:
  -> the lec interfaces
     -> the tables of arp tables(lec_arp_tables);
        -> the arp tables themselves
     -> the misc tables (lec_arp_empty_ones/lec_no_forward/mcast_fwds)

  Sum up of the call tree:
  atm_lec_seq_start()/atm_lec_seq_next()
  -> atm_lec_get_idx()
     -> atm_lec_itf_walk() (responsible for dev_lec/dev_put handling)
        -> atm_lec_priv_walk() (responsible for lec_priv locking)
           -> atm_lec_arp_walk()
              -> atm_lec_tbl_walk()
           -> atm_lec_misc_walk()
              -> atm_lec_tbl_walk()

  Each of the dedicated functions follows the same convention: return NULL
  as long as the seq_file cursor hasn't been digested (i.e. until < 0).
  Locking is only done when an entry (i.e. a lec_arp_table) is referenced.
  atm_lec_seq_stop()/atm_lec_itf_walk()/atm_lec_priv_walk() are responsible
  for getting this point right.
- module refcounting is done in atm_lec_seq_open()/atm_lec_seq_release();
- atm_lec_info() is removed.


 net/atm/proc.c |  339 +++++++++++++++++++++++++++++++++++++++------------------
 1 files changed, 233 insertions(+), 106 deletions(-)

diff -puN net/atm/proc.c~atm-proc-seq-lec-conversion net/atm/proc.c
--- linux-2.5.74-1.1360.1.1-to-1.1384/net/atm/proc.c~atm-proc-seq-lec-conversion	Wed Jul  9 01:43:10 2003
+++ linux-2.5.74-1.1360.1.1-to-1.1384-fr/net/atm/proc.c	Wed Jul  9 01:43:10 2003
@@ -338,54 +338,45 @@ static void svc_info(struct seq_file *se
 
 #if defined(CONFIG_ATM_LANE) || defined(CONFIG_ATM_LANE_MODULE)
 
-static char*
-lec_arp_get_status_string(unsigned char status)
+static char* lec_arp_get_status_string(unsigned char status)
 {
-  switch(status) {
-  case ESI_UNKNOWN:
-    return "ESI_UNKNOWN       ";
-  case ESI_ARP_PENDING:
-    return "ESI_ARP_PENDING   ";
-  case ESI_VC_PENDING:
-    return "ESI_VC_PENDING    ";
-  case ESI_FLUSH_PENDING:
-    return "ESI_FLUSH_PENDING ";
-  case ESI_FORWARD_DIRECT:
-    return "ESI_FORWARD_DIRECT";
-  default:
-    return "<Unknown>         ";
-  }
-}
-
-static void 
-lec_info(struct lec_arp_table *entry, char *buf)
-{
-        int j, offset=0;
-
-        for(j=0;j<ETH_ALEN;j++) {
-                offset+=sprintf(buf+offset,"%2.2x",0xff&entry->mac_addr[j]);
+	static char *lec_arp_status_string[] = {
+		"ESI_UNKNOWN       ",
+		"ESI_ARP_PENDING   ",
+		"ESI_VC_PENDING    ",
+		"ESI_FLUSH_PENDING ",
+		"ESI_FORWARD_DIRECT",
+		"<Unknown>         "
+	};
+
+	if (status > ESI_FORWARD_DIRECT - 1)
+		status = ESI_FORWARD_DIRECT;
+	return lec_arp_status_string[status - ESI_UNKNOWN];
+}
+
+static void lec_info(struct seq_file *seq, struct lec_arp_table *entry)
+{
+	int i;
+
+	for (i = 0; i < ETH_ALEN; i++)
+		seq_printf(seq, "%2.2x", entry->mac_addr[i] & 0xff);
+	seq_printf(seq, " ");
+	for (i = 0; i < ATM_ESA_LEN; i++)
+		seq_printf(seq, "%2.2x", entry->atm_addr[i] & 0xff);
+	seq_printf(seq, " %s %4.4x", lec_arp_get_status_string(entry->status),
+		   entry->flags & 0xffff);
+	if (entry->vcc)
+		seq_printf(seq, "%3d %3d ", entry->vcc->vpi, entry->vcc->vci);
+	else
+	        seq_printf(seq, "        ");
+	if (entry->recv_vcc) {
+		seq_printf(seq, "     %3d %3d", entry->recv_vcc->vpi,
+			   entry->recv_vcc->vci);
         }
-        offset+=sprintf(buf+offset, " ");
-        for(j=0;j<ATM_ESA_LEN;j++) {
-                offset+=sprintf(buf+offset,"%2.2x",0xff&entry->atm_addr[j]);
-        }
-        offset+=sprintf(buf+offset, " %s %4.4x",
-                        lec_arp_get_status_string(entry->status),
-                        entry->flags&0xffff);
-        if (entry->vcc) {
-                offset+=sprintf(buf+offset, "%3d %3d ", entry->vcc->vpi, 
-                                entry->vcc->vci);                
-        } else
-                offset+=sprintf(buf+offset, "        ");
-        if (entry->recv_vcc) {
-                offset+=sprintf(buf+offset, "     %3d %3d", 
-                                entry->recv_vcc->vpi, entry->recv_vcc->vci);
-        }
-
-        sprintf(buf+offset,"\n");
+        seq_putc(seq, '\n');
 }
 
-#endif
+#endif /* CONFIG_ATM_LANE */
 
 static __inline__ void *dev_get_idx(struct seq_file *seq, loff_t left)
 {
@@ -706,78 +697,214 @@ static struct file_operations atm_seq_ar
 #endif /* CONFIG_ATM_CLIP */
 
 #if defined(CONFIG_ATM_LANE) || defined(CONFIG_ATM_LANE_MODULE)
-static int atm_lec_info(loff_t pos,char *buf)
-{
+
+struct atm_lec_state {
 	unsigned long flags;
-	struct lec_priv *priv;
+	struct lec_priv *locked;
 	struct lec_arp_table *entry;
-	int i, count, d, e;
 	struct net_device *dev;
+	int itf;
+	union {
+		int arp_table;
+		int misc_table;
+	} u;
+};
+
+static void *atm_lec_tbl_walk(struct atm_lec_state *state,
+			      struct lec_arp_table *tbl, loff_t *l)
+{
+	struct lec_arp_table *e = state->entry;
+
+	if (!e)
+		e = tbl;
+	if (e == (void *)1) {
+		e = tbl;
+		--*l;
+	}
+	for (; e; e = e->next) {
+		if (--*l < 0)
+			break;
+	}
+	state->entry = e;
+	return e;
+}
+
+static void *atm_lec_arp_walk(struct atm_lec_state *state, loff_t *l,
+			      struct lec_priv *priv)
+{
+	void *v = state;
+	int p;
 
-	if (!pos) {
-		return sprintf(buf,"Itf  MAC          ATM destination"
-		    "                          Status            Flags "
-		    "VPI/VCI Recv VPI/VCI\n");
+	for (p = state->u.arp_table; p < LEC_ARP_TABLE_SIZE; p++) {
+		v = atm_lec_tbl_walk(state, priv->lec_arp_tables[p], l);
+		if (v)
+			break;
 	}
-	if (!try_atm_lane_ops())
-		return 0; /* the lane module is not there yet */
+	state->u.arp_table = v ? p : 0;
+	return v;
+}
 
-	count = pos;
-	for(d = 0; d < MAX_LEC_ITF; d++) {
-		dev = atm_lane_ops->get_lec(d);
-		if (!dev || !(priv = (struct lec_priv *) dev->priv))
-			continue;
-		spin_lock_irqsave(&priv->lec_arp_lock, flags);
-		for(i = 0; i < LEC_ARP_TABLE_SIZE; i++) {
-			for(entry = priv->lec_arp_tables[i]; entry; entry = entry->next) {
-				if (--count)
-					continue;
-				e = sprintf(buf,"%s ", dev->name);
-				lec_info(entry, buf+e);
-				spin_unlock_irqrestore(&priv->lec_arp_lock, flags);
-				dev_put(dev);
-				module_put(atm_lane_ops->owner);
-				return strlen(buf);
-			}
-		}
-		for(entry = priv->lec_arp_empty_ones; entry; entry = entry->next) {
-			if (--count)
-				continue;
-			e = sprintf(buf,"%s ", dev->name);
-			lec_info(entry, buf+e);
-			spin_unlock_irqrestore(&priv->lec_arp_lock, flags);
-			dev_put(dev);
-			module_put(atm_lane_ops->owner);
-			return strlen(buf);
-		}
-		for(entry = priv->lec_no_forward; entry; entry=entry->next) {
-			if (--count)
-				continue;
-			e = sprintf(buf,"%s ", dev->name);
-			lec_info(entry, buf+e);
-			spin_unlock_irqrestore(&priv->lec_arp_lock, flags);
-			dev_put(dev);
-			module_put(atm_lane_ops->owner);
-			return strlen(buf);
-		}
-		for(entry = priv->mcast_fwds; entry; entry = entry->next) {
-			if (--count)
-				continue;
-			e = sprintf(buf,"%s ", dev->name);
-			lec_info(entry, buf+e);
-			spin_unlock_irqrestore(&priv->lec_arp_lock, flags);
-			dev_put(dev);
-			module_put(atm_lane_ops->owner);
-			return strlen(buf);
-		}
-		spin_unlock_irqrestore(&priv->lec_arp_lock, flags);
+static void *atm_lec_misc_walk(struct atm_lec_state *state, loff_t *l,
+			       struct lec_priv *priv)
+{
+	struct lec_arp_table *lec_misc_tables[] = {
+		priv->lec_arp_empty_ones,
+		priv->lec_no_forward,
+		priv->mcast_fwds
+	};
+	void *v = state;
+	int q;
+
+	for (q = state->u.misc_table; q < ARRAY_SIZE(lec_misc_tables); q++) {
+		v = atm_lec_tbl_walk(state, lec_misc_tables[q], l);
+		if (v)
+			break;
+	}
+	state->u.misc_table = v ? q : 0;
+	return v;
+}
+
+static void *atm_lec_priv_walk(struct atm_lec_state *state, loff_t *l,
+			       struct lec_priv *priv)
+{
+	if (!state->locked) {
+		state->locked = priv;
+		spin_lock_irqsave(&priv->lec_arp_lock, state->flags);
+	}
+	if (!atm_lec_arp_walk(state, l, priv) &&
+	    !atm_lec_misc_walk(state, l, priv)) {
+		spin_unlock_irqrestore(&priv->lec_arp_lock, state->flags);
+		state->locked = NULL;
+	}
+	return state->locked;
+}
+
+static void *atm_lec_itf_walk(struct atm_lec_state *state, loff_t *l)
+{
+	struct net_device *dev;
+	void *v;
+
+	dev = state->dev ? state->dev : atm_lane_ops->get_lec(state->itf);
+	v = (dev && dev->priv) ? atm_lec_priv_walk(state, l, dev->priv) : NULL;
+	if (!v && dev) {
 		dev_put(dev);
+		dev = NULL;
+	}
+	state->dev = dev;
+	return v;
+}
+
+static void *atm_lec_get_idx(struct atm_lec_state *state, loff_t l)
+{
+	void *v = NULL;
+
+	for (; state->itf < MAX_LEC_ITF; state->itf++) {
+		v = atm_lec_itf_walk(state, &l);
+		if (v)
+			break;
+	}
+	return v; 
+}
+
+static void *atm_lec_seq_start(struct seq_file *seq, loff_t *pos)
+{
+	struct atm_lec_state *state = seq->private;
+
+	state->itf = 0;
+	state->dev = NULL;
+	state->locked = NULL;
+	state->u.arp_table = 0;
+	state->entry = (void *)1;
+
+	return *pos ? atm_lec_get_idx(state, *pos) : (void*)1;
+}
+
+static void atm_lec_seq_stop(struct seq_file *seq, void *v)
+{
+	struct atm_lec_state *state = seq->private;
+
+	if (state->dev) {
+		spin_unlock_irqrestore(&state->locked->lec_arp_lock,
+				       state->flags);
+		dev_put(state->dev);
+	}
+}
+
+static void *atm_lec_seq_next(struct seq_file *seq, void *v, loff_t *pos)
+{
+	struct atm_lec_state *state = seq->private;
+
+	v = atm_lec_get_idx(state, 1);
+	*pos += !!PTR_ERR(v);
+	return v;
+}
+
+static int atm_lec_seq_show(struct seq_file *seq, void *v)
+{
+	static char atm_lec_banner[] = "Itf  MAC          ATM destination" 
+		"                          Status            Flags "
+		"VPI/VCI Recv VPI/VCI\n";
+
+	if (v == (void *)1)
+		seq_puts(seq, atm_lec_banner);
+	else {
+		struct atm_lec_state *state = seq->private;
+		struct net_device *dev = state->dev; 
+
+		seq_printf(seq, "%s ", dev->name);
+		lec_info(seq, state->entry);
 	}
-	module_put(atm_lane_ops->owner);
 	return 0;
 }
-#endif
 
+static struct seq_operations atm_lec_seq_ops = {
+	.start	= atm_lec_seq_start,
+	.next	= atm_lec_seq_next,
+	.stop	= atm_lec_seq_stop,
+	.show	= atm_lec_seq_show,
+};
+
+static int atm_lec_seq_open(struct inode *inode, struct file *file)
+{
+	struct atm_lec_state *state;
+	struct seq_file *seq;
+	int rc = -EAGAIN;
+
+	if (!try_atm_lane_ops())
+		goto out;
+
+	state = kmalloc(sizeof(*state), GFP_KERNEL);
+	if (!state) {
+		rc = -ENOMEM;
+		goto out;
+	}
+
+	rc = seq_open(file, &atm_lec_seq_ops);
+	if (rc)
+		goto out_kfree;
+	seq = file->private_data;
+	seq->private = state;
+out:
+	return rc;
+out_kfree:
+	kfree(state);
+	goto out;
+}
+
+static int atm_lec_seq_release(struct inode *inode, struct file *file)
+{
+	module_put(atm_lane_ops->owner);
+	return seq_release_private(inode, file);
+}
+
+static struct file_operations atm_seq_lec_fops = {
+	.open		= atm_lec_seq_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= atm_lec_seq_release,
+};
+
+#endif /* CONFIG_ATM_LANE */
 
 static ssize_t proc_dev_atm_read(struct file *file,char *buf,size_t count,
     loff_t *pos)
@@ -915,7 +1042,7 @@ int __init atm_proc_init(void)
 	CREATE_SEQ_ENTRY(arp);
 #endif
 #if defined(CONFIG_ATM_LANE) || defined(CONFIG_ATM_LANE_MODULE)
-	CREATE_ENTRY(lec);
+	CREATE_SEQ_ENTRY(lec);
 #endif
 	return 0;
 

_

[PATCH 8/8] 2.5.74 - seq_file conversion of /proc/net/atm (cleanup)

[Francois Romieu]

- introduction of the struct array 'atm_proc_ents':
  - removal of code duplication in atm_proc_cleanup();
  - removal of code duplication in atm_proc_init();
  - removal of the macros CREATE_SEQ_ENTRY() and CREATE_ENTRY();
- credits/responsibility for the mess at the top of the file.


 net/atm/proc.c |  156 +++++++++++++++++++++------------------------------------
 1 files changed, 58 insertions(+), 98 deletions(-)

diff -puN net/atm/proc.c~atm-proc-seq-post-conversion-removal net/atm/proc.c
--- linux-2.5.74-1.1360.1.1-to-1.1384/net/atm/proc.c~atm-proc-seq-post-conversion-removal	Wed Jul  9 01:43:11 2003
+++ linux-2.5.74-1.1360.1.1-to-1.1384-fr/net/atm/proc.c	Wed Jul  9 01:43:11 2003
@@ -1,21 +1,13 @@
-/* net/atm/proc.c - ATM /proc interface */
-
-/* Written 1995-2000 by Werner Almesberger, EPFL LRC/ICA */
-
-/*
- * The mechanism used here isn't designed for speed but rather for convenience
- * of implementation. We only return one entry per read system call, so we can
- * be reasonably sure not to overrun the page and race conditions may lead to
- * the addition or omission of some lines but never to any corruption of a
- * line's internal structure.
+/* net/atm/proc.c - ATM /proc interface
+ *
+ * Written 1995-2000 by Werner Almesberger, EPFL LRC/ICA
  *
- * Making the whole thing slightly more efficient is left as an exercise to the
- * reader. (Suggestions: wrapper which loops to get several entries per system
- * call; or make --left slightly more clever to avoid O(n^2) characteristics.)
- * I find it fast enough on my unloaded 266 MHz Pentium 2 :-)
+ * seq_file api usage by romieu@fr.zoreil.com
+ *
+ * Evaluating the efficiency of the whole thing if left as an exercise to
+ * the reader.
  */
 
-
 #include <linux/config.h>
 #include <linux/module.h> /* for EXPORT_SYMBOL */
 #include <linux/string.h>
@@ -52,19 +44,12 @@
 
 static ssize_t proc_dev_atm_read(struct file *file,char *buf,size_t count,
     loff_t *pos);
-static ssize_t proc_spec_atm_read(struct file *file,char *buf,size_t count,
-    loff_t *pos);
 
 static struct file_operations proc_dev_atm_operations = {
 	.owner =	THIS_MODULE,
 	.read =		proc_dev_atm_read,
 };
 
-static struct file_operations proc_spec_atm_operations = {
-	.owner =	THIS_MODULE,
-	.read =		proc_spec_atm_read,
-};
-
 static void add_stats(struct seq_file *seq, const char *aal,
   const struct k_atm_aal_stats *stats)
 {
@@ -931,33 +916,9 @@ static ssize_t proc_dev_atm_read(struct 
 	return length;
 }
 
-
-static ssize_t proc_spec_atm_read(struct file *file,char *buf,size_t count,
-    loff_t *pos)
-{
-	unsigned long page;
-	int length;
-	int (*info)(loff_t,char *);
-	info = PDE(file->f_dentry->d_inode)->data;
-
-	if (count == 0) return 0;
-	page = get_zeroed_page(GFP_KERNEL);
-	if (!page) return -ENOMEM;
-	length = (*info)(*pos,(char *) page);
-	if (length > count) length = -EINVAL;
-	if (length >= 0) {
-		if (copy_to_user(buf,(char *) page,length)) length = -EFAULT;
-		(*pos)++;
-	}
-	free_page(page);
-	return length;
-}
-
-
 struct proc_dir_entry *atm_proc_root;
 EXPORT_SYMBOL(atm_proc_root);
 
-
 int atm_proc_dev_register(struct atm_dev *dev)
 {
 	int digits,num;
@@ -986,72 +947,71 @@ fail1:
 	return error;
 }
 
-
 void atm_proc_dev_deregister(struct atm_dev *dev)
 {
 	remove_proc_entry(dev->proc_name, atm_proc_root);
 	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 = &atm_seq_##name##_fops; \
-		name->owner = THIS_MODULE; \
-	} while (0)
-
-#define CREATE_ENTRY(name) \
-    name = create_proc_entry(#name,0,atm_proc_root); \
-    if (!name) goto cleanup; \
-    name->data = atm_##name##_info; \
-    name->proc_fops = &proc_spec_atm_operations; \
-    name->owner = THIS_MODULE
-
-static struct proc_dir_entry *devices = NULL, *pvc = NULL,
-		*svc = NULL, *arp = NULL, *lec = NULL, *vc = NULL;
-
-static void atm_proc_cleanup(void)
-{
-	if (devices)
-		remove_proc_entry("devices",atm_proc_root);
-	if (pvc)
-		remove_proc_entry("pvc",atm_proc_root);
-	if (svc)
-		remove_proc_entry("svc",atm_proc_root);
-	if (arp)
-		remove_proc_entry("arp",atm_proc_root);
-	if (lec)
-		remove_proc_entry("lec",atm_proc_root);
-	if (vc)
-		remove_proc_entry("vc",atm_proc_root);
-	remove_proc_entry("net/atm",NULL);
+static struct atm_proc_entry {
+	char *name;
+	struct file_operations *proc_fops;
+	struct proc_dir_entry *dirent;
+} atm_proc_ents[] = {
+	{ .name = "devices",	.proc_fops = &atm_seq_devices_fops },
+	{ .name = "pvc",	.proc_fops = &atm_seq_pvc_fops },
+	{ .name = "svc",	.proc_fops = &atm_seq_svc_fops },
+	{ .name = "vc",		.proc_fops = &atm_seq_vc_fops },
+#if defined(CONFIG_ATM_CLIP) || defined(CONFIG_ATM_CLIP_MODULE)
+	{ .name = "arp",	.proc_fops = &atm_seq_arp_fops },
+#endif
+#if defined(CONFIG_ATM_LANE) || defined(CONFIG_ATM_LANE_MODULE)
+	{ .name = "lec",	.proc_fops = &atm_seq_lec_fops },
+#endif
+	{ .name = NULL,		.proc_fops = NULL }
+};
+
+static void atm_proc_dirs_remove(void)
+{
+	static struct atm_proc_entry *e;
+
+	for (e = atm_proc_ents; e->name; e++) {
+		if (e->dirent) 
+			remove_proc_entry(e->name, atm_proc_root);
+	}
+	remove_proc_entry("net/atm", NULL);
 }
 
 int __init atm_proc_init(void)
 {
+	static struct atm_proc_entry *e;
+	int ret;
+
 	atm_proc_root = proc_mkdir("net/atm",NULL);
 	if (!atm_proc_root)
-		return -ENOMEM;
-	CREATE_SEQ_ENTRY(devices);
-	CREATE_SEQ_ENTRY(pvc);
-	CREATE_SEQ_ENTRY(svc);
-	CREATE_SEQ_ENTRY(vc);
-#if defined(CONFIG_ATM_CLIP) || defined(CONFIG_ATM_CLIP_MODULE)
-	CREATE_SEQ_ENTRY(arp);
-#endif
-#if defined(CONFIG_ATM_LANE) || defined(CONFIG_ATM_LANE_MODULE)
-	CREATE_SEQ_ENTRY(lec);
-#endif
-	return 0;
+		goto err_out;
+	for (e = atm_proc_ents; e->name; e++) {
+		struct proc_dir_entry *dirent;
+
+		dirent = create_proc_entry(e->name, S_IRUGO, atm_proc_root);
+		if (!dirent)
+			goto err_out_remove;
+		dirent->proc_fops = e->proc_fops;
+		dirent->owner = THIS_MODULE;
+		e->dirent = dirent;
+	}
+	ret = 0;
+out:
+	return ret;
 
-cleanup:
-	atm_proc_cleanup();
-	return -ENOMEM;
+err_out_remove:
+	atm_proc_dirs_remove();
+err_out:
+	ret = -ENOMEM;
+	goto out;
 }
 
-void atm_proc_exit(void)
+void __exit atm_proc_exit(void)
 {
-	atm_proc_cleanup();
+	atm_proc_dirs_remove();
 }

_

Re: [PATCHKIT] 2.5.74 - seq_file conversion of /proc/net/atm

[David S. Miller]

Chas, will you merge this stuff to me?  It looks fine as far
as I can tell.

Re: [PATCHKIT] 2.5.74 - seq_file conversion of /proc/net/atm

[chas williams]

In message <20030709.224926.26511362.davem@redhat.com>,"David S. Miller" writes:
>Chas, will you merge this stuff to me?  It looks fine as far
>as I can tell.

i will.  i wanted to test some of the bits that werent
well tested but didnt have time yesterday.