[PATCH 00/10] staging: Clean up ozwpan driver

[PATCH 00/10] staging: Clean up ozwpan driver

[Christoph Jaeger]

This patch set does some cleanup; no functional change.

Christoph Jaeger (10):
  staging: ozwpan: Add module parameter description
  staging: ozwpan: Fix typo in typedef
  staging: ozwpan: Remove unused OZ_MAX_TIMER_POOL_SIZE
  staging: ozwpan: Remove redundant initialization
  staging: ozwpan: Remove dead code
  staging: ozwpan: Simplify app interface
  staging: ozwpan: Use slab cache for oz_urb_link allocation
  staging: ozwpan: Use slab cache for oz_elt_info allocation
  staging: ozwpan: Use slab cache for oz_tx_frame allocation
  staging: ozwpan: Use list helpers

 drivers/staging/ozwpan/ozcdev.c     |  31 ++--
 drivers/staging/ozwpan/ozeltbuf.c   | 131 +++------------
 drivers/staging/ozwpan/ozeltbuf.h   |   7 +-
 drivers/staging/ozwpan/ozhcd.c      | 166 +++++--------------
 drivers/staging/ozwpan/ozmain.c     |   4 +-
 drivers/staging/ozwpan/ozpd.c       | 307 ++++++++++--------------------------
 drivers/staging/ozwpan/ozpd.h       |   9 +-
 drivers/staging/ozwpan/ozproto.c    |  36 +++--
 drivers/staging/ozwpan/ozproto.h    |   8 +-
 drivers/staging/ozwpan/ozprotocol.h |   2 -
 drivers/staging/ozwpan/ozusbsvc.c   |  30 ++--
 drivers/staging/ozwpan/ozusbsvc1.c  |  12 +-
 12 files changed, 223 insertions(+), 520 deletions(-)

-- 
1.9.1

[PATCH 01/10] staging: ozwpan: Add module parameter description

[Christoph Jaeger]

Signed-off-by: Christoph Jaeger <email@christophjaeger.info>
---
 drivers/staging/ozwpan/ozmain.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/staging/ozwpan/ozmain.c b/drivers/staging/ozwpan/ozmain.c
index d1a5b7a..7d6ef4c 100644
--- a/drivers/staging/ozwpan/ozmain.c
+++ b/drivers/staging/ozwpan/ozmain.c
@@ -25,6 +25,9 @@ unsigned int oz_dbg_mask = OZ_DEFAULT_DBG_MASK;
  * netcards. Bindings can be added later using an IOCTL.
  */
 static char *g_net_dev = "";
+module_param(g_net_dev, charp, S_IRUGO);
+MODULE_PARM_DESC(g_net_dev, "The device(s) to bind to; "
+	"'*' means all, '' (empty string; default) means none.");
 
 /*
  * Context: process
@@ -48,7 +51,6 @@ static void __exit ozwpan_exit(void)
 	oz_cdev_deregister();
 }
 
-module_param(g_net_dev, charp, S_IRUGO);
 module_init(ozwpan_init);
 module_exit(ozwpan_exit);
 
-- 
1.9.1

[PATCH 02/10] staging: ozwpan: Fix typo in typedef

[Christoph Jaeger]

Signed-off-by: Christoph Jaeger <email@christophjaeger.info>
---
 drivers/staging/ozwpan/ozproto.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/staging/ozwpan/ozproto.h b/drivers/staging/ozwpan/ozproto.h
index cb38e02..378b737 100644
--- a/drivers/staging/ozwpan/ozproto.h
+++ b/drivers/staging/ozwpan/ozproto.h
@@ -34,7 +34,7 @@ typedef void (*oz_app_term_fn_t)(void);
 typedef int (*oz_app_start_fn_t)(struct oz_pd *pd, int resume);
 typedef void (*oz_app_stop_fn_t)(struct oz_pd *pd, int pause);
 typedef void (*oz_app_rx_fn_t)(struct oz_pd *pd, struct oz_elt *elt);
-typedef int (*oz_app_hearbeat_fn_t)(struct oz_pd *pd);
+typedef int (*oz_app_heartbeat_fn_t)(struct oz_pd *pd);
 typedef void (*oz_app_farewell_fn_t)(struct oz_pd *pd, u8 ep_num,
 			u8 *data, u8 len);
 
@@ -44,7 +44,7 @@ struct oz_app_if {
 	oz_app_start_fn_t	start;
 	oz_app_stop_fn_t	stop;
 	oz_app_rx_fn_t		rx;
-	oz_app_hearbeat_fn_t	heartbeat;
+	oz_app_heartbeat_fn_t	heartbeat;
 	oz_app_farewell_fn_t	farewell;
 	int			app_id;
 };
-- 
1.9.1

Re: [PATCH 02/10] staging: ozwpan: Fix typo in typedef

[Greg KH]

On Mon, Aug 04, 2014 at 02:54:48PM +0200, Christoph Jaeger wrote:
> Signed-off-by: Christoph Jaeger <email@christophjaeger.info>
> ---
>  drivers/staging/ozwpan/ozproto.h | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/staging/ozwpan/ozproto.h b/drivers/staging/ozwpan/ozproto.h
> index cb38e02..378b737 100644
> --- a/drivers/staging/ozwpan/ozproto.h
> +++ b/drivers/staging/ozwpan/ozproto.h
> @@ -34,7 +34,7 @@ typedef void (*oz_app_term_fn_t)(void);
>  typedef int (*oz_app_start_fn_t)(struct oz_pd *pd, int resume);
>  typedef void (*oz_app_stop_fn_t)(struct oz_pd *pd, int pause);
>  typedef void (*oz_app_rx_fn_t)(struct oz_pd *pd, struct oz_elt *elt);
> -typedef int (*oz_app_hearbeat_fn_t)(struct oz_pd *pd);
> +typedef int (*oz_app_heartbeat_fn_t)(struct oz_pd *pd);
>  typedef void (*oz_app_farewell_fn_t)(struct oz_pd *pd, u8 ep_num,
>  			u8 *data, u8 len);
>  
> @@ -44,7 +44,7 @@ struct oz_app_if {
>  	oz_app_start_fn_t	start;
>  	oz_app_stop_fn_t	stop;
>  	oz_app_rx_fn_t		rx;
> -	oz_app_hearbeat_fn_t	heartbeat;
> +	oz_app_heartbeat_fn_t	heartbeat;
>  	oz_app_farewell_fn_t	farewell;
>  	int			app_id;
>  };

As these typedefs are only used in this one structure, there's no real
need for them, you can remove them in a later patch if you want.

thanks,

greg k-h

[PATCH 03/10] staging: ozwpan: Remove unused OZ_MAX_TIMER_POOL_SIZE

[Christoph Jaeger]

OZ_MAX_TIMER_POOL_SIZE is not used anywhere; remove it.

Signed-off-by: Christoph Jaeger <email@christophjaeger.info>
---
 drivers/staging/ozwpan/ozproto.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/drivers/staging/ozwpan/ozproto.c b/drivers/staging/ozwpan/ozproto.c
index 1102055..4aebe16 100644
--- a/drivers/staging/ozwpan/ozproto.c
+++ b/drivers/staging/ozwpan/ozproto.c
@@ -29,8 +29,6 @@
 #define OZ_DO_STOP		1
 #define OZ_DO_SLEEP		2
 
-#define OZ_MAX_TIMER_POOL_SIZE	16
-
 struct oz_binding {
 	struct packet_type ptype;
 	char name[OZ_MAX_BINDING_LEN];
-- 
1.9.1

[PATCH 04/10] staging: ozwpan: Remove redundant initialization

[Christoph Jaeger]

Member 'ops' has already been initialized by calling cdev_init().

Signed-off-by: Christoph Jaeger <email@christophjaeger.info>
---
 drivers/staging/ozwpan/ozcdev.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/drivers/staging/ozwpan/ozcdev.c b/drivers/staging/ozwpan/ozcdev.c
index 10c0a96..f82e12c 100644
--- a/drivers/staging/ozwpan/ozcdev.c
+++ b/drivers/staging/ozwpan/ozcdev.c
@@ -360,7 +360,6 @@ int oz_cdev_register(void)
 	       MAJOR(g_cdev.devnum), MINOR(g_cdev.devnum));
 	cdev_init(&g_cdev.cdev, &oz_fops);
 	g_cdev.cdev.owner = THIS_MODULE;
-	g_cdev.cdev.ops = &oz_fops;
 	spin_lock_init(&g_cdev.lock);
 	init_waitqueue_head(&g_cdev.rdq);
 	err = cdev_add(&g_cdev.cdev, g_cdev.devnum, 1);
-- 
1.9.1

[PATCH 05/10] staging: ozwpan: Remove dead code

[Christoph Jaeger]

No need to return a value from elt_buf_init().

Signed-off-by: Christoph Jaeger <email@christophjaeger.info>
---
 drivers/staging/ozwpan/ozeltbuf.c | 3 +--
 drivers/staging/ozwpan/ozeltbuf.h | 2 +-
 drivers/staging/ozwpan/ozpd.c     | 5 +----
 3 files changed, 3 insertions(+), 7 deletions(-)

diff --git a/drivers/staging/ozwpan/ozeltbuf.c b/drivers/staging/ozwpan/ozeltbuf.c
index bd560c6..f6e6481 100644
--- a/drivers/staging/ozwpan/ozeltbuf.c
+++ b/drivers/staging/ozwpan/ozeltbuf.c
@@ -16,7 +16,7 @@
 /*
  * Context: softirq-serialized
  */
-int oz_elt_buf_init(struct oz_elt_buf *buf)
+void oz_elt_buf_init(struct oz_elt_buf *buf)
 {
 	memset(buf, 0, sizeof(struct oz_elt_buf));
 	INIT_LIST_HEAD(&buf->stream_list);
@@ -24,7 +24,6 @@ int oz_elt_buf_init(struct oz_elt_buf *buf)
 	INIT_LIST_HEAD(&buf->isoc_list);
 	buf->max_free_elts = 32;
 	spin_lock_init(&buf->lock);
-	return 0;
 }
 
 /*
diff --git a/drivers/staging/ozwpan/ozeltbuf.h b/drivers/staging/ozwpan/ozeltbuf.h
index 03c12f5..3846432 100644
--- a/drivers/staging/ozwpan/ozeltbuf.h
+++ b/drivers/staging/ozwpan/ozeltbuf.h
@@ -50,7 +50,7 @@ struct oz_elt_buf {
 	u8 tx_seq_num[OZ_NB_APPS];
 };
 
-int oz_elt_buf_init(struct oz_elt_buf *buf);
+void oz_elt_buf_init(struct oz_elt_buf *buf);
 void oz_elt_buf_term(struct oz_elt_buf *buf);
 struct oz_elt_info *oz_elt_info_alloc(struct oz_elt_buf *buf);
 void oz_elt_info_free(struct oz_elt_buf *buf, struct oz_elt_info *ei);
diff --git a/drivers/staging/ozwpan/ozpd.c b/drivers/staging/ozwpan/ozpd.c
index 10f1b3a..a27c603 100644
--- a/drivers/staging/ozwpan/ozpd.c
+++ b/drivers/staging/ozwpan/ozpd.c
@@ -175,10 +175,7 @@ struct oz_pd *oz_pd_alloc(const u8 *mac_addr)
 		oz_pd_set_state(pd, OZ_PD_S_IDLE);
 		pd->max_tx_size = OZ_MAX_TX_SIZE;
 		ether_addr_copy(pd->mac_addr, mac_addr);
-		if (0 != oz_elt_buf_init(&pd->elt_buff)) {
-			kfree(pd);
-			pd = NULL;
-		}
+		oz_elt_buf_init(&pd->elt_buff);
 		spin_lock_init(&pd->tx_frame_lock);
 		INIT_LIST_HEAD(&pd->tx_queue);
 		INIT_LIST_HEAD(&pd->farewell_list);
-- 
1.9.1

[PATCH 06/10] staging: ozwpan: Simplify app interface

[Christoph Jaeger]

Simplify the somewhat overcomplicated application interface; improves
readability and saves a bunch of lines.

Use designated struct initializers for clarity.

Signed-off-by: Christoph Jaeger <email@christophjaeger.info>
---
 drivers/staging/ozwpan/ozcdev.c     |  30 +++----
 drivers/staging/ozwpan/ozpd.c       | 151 ++++++++++--------------------------
 drivers/staging/ozwpan/ozpd.h       |   4 +-
 drivers/staging/ozwpan/ozproto.c    |   2 +-
 drivers/staging/ozwpan/ozproto.h    |   1 -
 drivers/staging/ozwpan/ozprotocol.h |   2 -
 drivers/staging/ozwpan/ozusbsvc.c   |  30 +++----
 drivers/staging/ozwpan/ozusbsvc1.c  |  12 +--
 8 files changed, 82 insertions(+), 150 deletions(-)

diff --git a/drivers/staging/ozwpan/ozcdev.c b/drivers/staging/ozwpan/ozcdev.c
index f82e12c..c73d396 100644
--- a/drivers/staging/ozwpan/ozcdev.c
+++ b/drivers/staging/ozwpan/ozcdev.c
@@ -49,11 +49,11 @@ static struct oz_serial_ctx *oz_cdev_claim_ctx(struct oz_pd *pd)
 {
 	struct oz_serial_ctx *ctx;
 
-	spin_lock_bh(&pd->app_lock[OZ_APPID_SERIAL-1]);
-	ctx = (struct oz_serial_ctx *)pd->app_ctx[OZ_APPID_SERIAL-1];
+	spin_lock_bh(&pd->app_lock[OZ_APPID_SERIAL]);
+	ctx = (struct oz_serial_ctx *) pd->app_ctx[OZ_APPID_SERIAL];
 	if (ctx)
 		atomic_inc(&ctx->ref_count);
-	spin_unlock_bh(&pd->app_lock[OZ_APPID_SERIAL-1]);
+	spin_unlock_bh(&pd->app_lock[OZ_APPID_SERIAL]);
 	return ctx;
 }
 
@@ -182,8 +182,8 @@ static ssize_t oz_cdev_write(struct file *filp, const char __user *buf,
 	app_hdr->app_id = OZ_APPID_SERIAL;
 	if (copy_from_user(app_hdr+1, buf, count))
 		goto out;
-	spin_lock_bh(&pd->app_lock[OZ_APPID_USB-1]);
-	ctx = (struct oz_serial_ctx *)pd->app_ctx[OZ_APPID_SERIAL-1];
+	spin_lock_bh(&pd->app_lock[OZ_APPID_USB]);
+	ctx = (struct oz_serial_ctx *) pd->app_ctx[OZ_APPID_SERIAL];
 	if (ctx) {
 		app_hdr->elt_seq_num = ctx->tx_seq_num++;
 		if (ctx->tx_seq_num == 0)
@@ -193,7 +193,7 @@ static ssize_t oz_cdev_write(struct file *filp, const char __user *buf,
 			ei = NULL;
 		spin_unlock(&eb->lock);
 	}
-	spin_unlock_bh(&pd->app_lock[OZ_APPID_USB-1]);
+	spin_unlock_bh(&pd->app_lock[OZ_APPID_USB]);
 out:
 	if (ei) {
 		count = 0;
@@ -436,14 +436,14 @@ int oz_cdev_start(struct oz_pd *pd, int resume)
 		return -ENOMEM;
 	atomic_set(&ctx->ref_count, 1);
 	ctx->tx_seq_num = 1;
-	spin_lock_bh(&pd->app_lock[OZ_APPID_SERIAL-1]);
-	old_ctx = pd->app_ctx[OZ_APPID_SERIAL-1];
+	spin_lock_bh(&pd->app_lock[OZ_APPID_SERIAL]);
+	old_ctx = pd->app_ctx[OZ_APPID_SERIAL];
 	if (old_ctx) {
-		spin_unlock_bh(&pd->app_lock[OZ_APPID_SERIAL-1]);
+		spin_unlock_bh(&pd->app_lock[OZ_APPID_SERIAL]);
 		kfree(ctx);
 	} else {
-		pd->app_ctx[OZ_APPID_SERIAL-1] = ctx;
-		spin_unlock_bh(&pd->app_lock[OZ_APPID_SERIAL-1]);
+		pd->app_ctx[OZ_APPID_SERIAL] = ctx;
+		spin_unlock_bh(&pd->app_lock[OZ_APPID_SERIAL]);
 	}
 	spin_lock(&g_cdev.lock);
 	if ((g_cdev.active_pd == NULL) &&
@@ -468,10 +468,10 @@ void oz_cdev_stop(struct oz_pd *pd, int pause)
 		oz_dbg(ON, "Serial service paused\n");
 		return;
 	}
-	spin_lock_bh(&pd->app_lock[OZ_APPID_SERIAL-1]);
-	ctx = (struct oz_serial_ctx *)pd->app_ctx[OZ_APPID_SERIAL-1];
-	pd->app_ctx[OZ_APPID_SERIAL-1] = NULL;
-	spin_unlock_bh(&pd->app_lock[OZ_APPID_SERIAL-1]);
+	spin_lock_bh(&pd->app_lock[OZ_APPID_SERIAL]);
+	ctx = (struct oz_serial_ctx *) pd->app_ctx[OZ_APPID_SERIAL];
+	pd->app_ctx[OZ_APPID_SERIAL] = NULL;
+	spin_unlock_bh(&pd->app_lock[OZ_APPID_SERIAL]);
 	if (ctx)
 		oz_cdev_release_ctx(ctx);
 	spin_lock(&g_cdev.lock);
diff --git a/drivers/staging/ozwpan/ozpd.c b/drivers/staging/ozwpan/ozpd.c
index a27c603..6c4b13f 100644
--- a/drivers/staging/ozwpan/ozpd.c
+++ b/drivers/staging/ozwpan/ozpd.c
@@ -32,11 +32,6 @@ static void oz_retire_frame(struct oz_pd *pd, struct oz_tx_frame *f);
 static void oz_isoc_stream_free(struct oz_isoc_stream *st);
 static int oz_send_next_queued_frame(struct oz_pd *pd, int more_data);
 static void oz_isoc_destructor(struct sk_buff *skb);
-static int oz_def_app_init(void);
-static void oz_def_app_term(void);
-static int oz_def_app_start(struct oz_pd *pd, int resume);
-static void oz_def_app_stop(struct oz_pd *pd, int pause);
-static void oz_def_app_rx(struct oz_pd *pd, struct oz_elt *elt);
 
 /*
  * Counts the uncompleted isoc frames submitted to netcard.
@@ -45,80 +40,25 @@ static atomic_t g_submitted_isoc = ATOMIC_INIT(0);
 
 /* Application handler functions.
  */
-static const struct oz_app_if g_app_if[OZ_APPID_MAX] = {
-	{oz_usb_init,
-	oz_usb_term,
-	oz_usb_start,
-	oz_usb_stop,
-	oz_usb_rx,
-	oz_usb_heartbeat,
-	oz_usb_farewell,
-	OZ_APPID_USB},
-
-	{oz_def_app_init,
-	oz_def_app_term,
-	oz_def_app_start,
-	oz_def_app_stop,
-	oz_def_app_rx,
-	NULL,
-	NULL,
-	OZ_APPID_UNUSED1},
-
-	{oz_def_app_init,
-	oz_def_app_term,
-	oz_def_app_start,
-	oz_def_app_stop,
-	oz_def_app_rx,
-	NULL,
-	NULL,
-	OZ_APPID_UNUSED2},
-
-	{oz_cdev_init,
-	oz_cdev_term,
-	oz_cdev_start,
-	oz_cdev_stop,
-	oz_cdev_rx,
-	NULL,
-	NULL,
-	OZ_APPID_SERIAL},
+static const struct oz_app_if g_app_if[OZ_NB_APPS] = {
+	[OZ_APPID_USB] = {
+		.init      = oz_usb_init,
+		.term      = oz_usb_term,
+		.start     = oz_usb_start,
+		.stop      = oz_usb_stop,
+		.rx        = oz_usb_rx,
+		.heartbeat = oz_usb_heartbeat,
+		.farewell  = oz_usb_farewell,
+	},
+	[OZ_APPID_SERIAL] = {
+		.init      = oz_cdev_init,
+		.term      = oz_cdev_term,
+		.start     = oz_cdev_start,
+		.stop      = oz_cdev_stop,
+		.rx        = oz_cdev_rx,
+	},
 };
 
-/*
- * Context: process
- */
-static int oz_def_app_init(void)
-{
-	return 0;
-}
-
-/*
- * Context: process
- */
-static void oz_def_app_term(void)
-{
-}
-
-/*
- * Context: softirq
- */
-static int oz_def_app_start(struct oz_pd *pd, int resume)
-{
-	return 0;
-}
-
-/*
- * Context: softirq
- */
-static void oz_def_app_stop(struct oz_pd *pd, int pause)
-{
-}
-
-/*
- * Context: softirq
- */
-static void oz_def_app_rx(struct oz_pd *pd, struct oz_elt *elt)
-{
-}
 
 /*
  * Context: softirq or process
@@ -169,7 +109,7 @@ struct oz_pd *oz_pd_alloc(const u8 *mac_addr)
 	if (pd) {
 		int i;
 		atomic_set(&pd->ref_count, 2);
-		for (i = 0; i < OZ_APPID_MAX; i++)
+		for (i = 0; i < OZ_NB_APPS; i++)
 			spin_lock_init(&pd->app_lock[i]);
 		pd->last_rx_pkt_num = 0xffffffff;
 		oz_pd_set_state(pd, OZ_PD_S_IDLE);
@@ -269,23 +209,21 @@ void oz_pd_destroy(struct oz_pd *pd)
  */
 int oz_services_start(struct oz_pd *pd, u16 apps, int resume)
 {
-	const struct oz_app_if *ai;
-	int rc = 0;
+	int i, rc = 0;
 
 	oz_pd_dbg(pd, ON, "%s: (0x%x) resume(%d)\n", __func__, apps, resume);
-	for (ai = g_app_if; ai < &g_app_if[OZ_APPID_MAX]; ai++) {
-		if (apps & (1<<ai->app_id)) {
-			if (ai->start(pd, resume)) {
+	for (i = 0; i < OZ_NB_APPS; i++) {
+		if (g_app_if[i].start && (apps & (1 << i))) {
+			if (g_app_if[i].start(pd, resume)) {
 				rc = -1;
 				oz_pd_dbg(pd, ON,
-					  "Unable to start service %d\n",
-					  ai->app_id);
+					  "Unable to start service %d\n", i);
 				break;
 			}
 			spin_lock_bh(&g_polling_lock);
-			pd->total_apps |= (1<<ai->app_id);
+			pd->total_apps |= (1 << i);
 			if (resume)
-				pd->paused_apps &= ~(1<<ai->app_id);
+				pd->paused_apps &= ~(1 << i);
 			spin_unlock_bh(&g_polling_lock);
 		}
 	}
@@ -297,20 +235,20 @@ int oz_services_start(struct oz_pd *pd, u16 apps, int resume)
  */
 void oz_services_stop(struct oz_pd *pd, u16 apps, int pause)
 {
-	const struct oz_app_if *ai;
+	int i;
 
 	oz_pd_dbg(pd, ON, "%s: (0x%x) pause(%d)\n", __func__, apps, pause);
-	for (ai = g_app_if; ai < &g_app_if[OZ_APPID_MAX]; ai++) {
-		if (apps & (1<<ai->app_id)) {
+	for (i = 0; i < OZ_NB_APPS; i++) {
+		if (g_app_if[i].stop && (apps & (1 << i))) {
 			spin_lock_bh(&g_polling_lock);
 			if (pause) {
-				pd->paused_apps |= (1<<ai->app_id);
+				pd->paused_apps |=  (1 << i);
 			} else {
-				pd->total_apps &= ~(1<<ai->app_id);
-				pd->paused_apps &= ~(1<<ai->app_id);
+				pd->total_apps  &= ~(1 << i);
+				pd->paused_apps &= ~(1 << i);
 			}
 			spin_unlock_bh(&g_polling_lock);
-			ai->stop(pd, pause);
+			g_app_if[i].stop(pd, pause);
 		}
 	}
 }
@@ -320,12 +258,11 @@ void oz_services_stop(struct oz_pd *pd, u16 apps, int pause)
  */
 void oz_pd_heartbeat(struct oz_pd *pd, u16 apps)
 {
-	const struct oz_app_if *ai;
-	int more = 0;
+	int i, more = 0;
 
-	for (ai = g_app_if; ai < &g_app_if[OZ_APPID_MAX]; ai++) {
-		if (ai->heartbeat && (apps & (1<<ai->app_id))) {
-			if (ai->heartbeat(pd))
+	for (i = 0; i < OZ_NB_APPS; i++) {
+		if (g_app_if[i].heartbeat && (apps & (1 << i))) {
+			if (g_app_if[i].heartbeat(pd))
 				more = 1;
 		}
 	}
@@ -957,9 +894,10 @@ void oz_apps_init(void)
 {
 	int i;
 
-	for (i = 0; i < OZ_APPID_MAX; i++)
+	for (i = 0; i < OZ_NB_APPS; i++) {
 		if (g_app_if[i].init)
 			g_app_if[i].init();
+	}
 }
 
 /*
@@ -970,9 +908,10 @@ void oz_apps_term(void)
 	int i;
 
 	/* Terminate all the apps. */
-	for (i = 0; i < OZ_APPID_MAX; i++)
+	for (i = 0; i < OZ_NB_APPS; i++) {
 		if (g_app_if[i].term)
 			g_app_if[i].term();
+	}
 }
 
 /*
@@ -980,12 +919,8 @@ void oz_apps_term(void)
  */
 void oz_handle_app_elt(struct oz_pd *pd, u8 app_id, struct oz_elt *elt)
 {
-	const struct oz_app_if *ai;
-
-	if (app_id == 0 || app_id > OZ_APPID_MAX)
-		return;
-	ai = &g_app_if[app_id-1];
-	ai->rx(pd, elt);
+	if (app_id < OZ_NB_APPS && g_app_if[app_id].rx)
+		g_app_if[app_id].rx(pd, elt);
 }
 
 /*
@@ -994,7 +929,7 @@ void oz_handle_app_elt(struct oz_pd *pd, u8 app_id, struct oz_elt *elt)
 void oz_pd_indicate_farewells(struct oz_pd *pd)
 {
 	struct oz_farewell *f;
-	const struct oz_app_if *ai = &g_app_if[OZ_APPID_USB-1];
+	const struct oz_app_if *ai = &g_app_if[OZ_APPID_USB];
 
 	while (1) {
 		spin_lock_bh(&g_polling_lock);
diff --git a/drivers/staging/ozwpan/ozpd.h b/drivers/staging/ozwpan/ozpd.h
index ad5fe7a..3b3b3ce 100644
--- a/drivers/staging/ozwpan/ozpd.h
+++ b/drivers/staging/ozwpan/ozpd.h
@@ -81,8 +81,8 @@ struct oz_pd {
 	unsigned long	presleep;
 	unsigned long	keep_alive;
 	struct oz_elt_buf elt_buff;
-	void		*app_ctx[OZ_APPID_MAX];
-	spinlock_t	app_lock[OZ_APPID_MAX];
+	void		*app_ctx[OZ_NB_APPS];
+	spinlock_t	app_lock[OZ_NB_APPS];
 	int		max_tx_size;
 	u8		mode;
 	u8		ms_per_isoc;
diff --git a/drivers/staging/ozwpan/ozproto.c b/drivers/staging/ozwpan/ozproto.c
index 4aebe16..549fe7f 100644
--- a/drivers/staging/ozwpan/ozproto.c
+++ b/drivers/staging/ozwpan/ozproto.c
@@ -614,7 +614,7 @@ struct oz_pd *oz_pd_find(const u8 *mac_addr)
  */
 void oz_app_enable(int app_id, int enable)
 {
-	if (app_id <= OZ_APPID_MAX) {
+	if (app_id < OZ_NB_APPS) {
 		spin_lock_bh(&g_polling_lock);
 		if (enable)
 			g_apps |= (1<<app_id);
diff --git a/drivers/staging/ozwpan/ozproto.h b/drivers/staging/ozwpan/ozproto.h
index 378b737..f1d30c4 100644
--- a/drivers/staging/ozwpan/ozproto.h
+++ b/drivers/staging/ozwpan/ozproto.h
@@ -46,7 +46,6 @@ struct oz_app_if {
 	oz_app_rx_fn_t		rx;
 	oz_app_heartbeat_fn_t	heartbeat;
 	oz_app_farewell_fn_t	farewell;
-	int			app_id;
 };
 
 int oz_protocol_init(char *devs);
diff --git a/drivers/staging/ozwpan/ozprotocol.h b/drivers/staging/ozwpan/ozprotocol.h
index 9bbb182..4642072 100644
--- a/drivers/staging/ozwpan/ozprotocol.h
+++ b/drivers/staging/ozwpan/ozprotocol.h
@@ -139,8 +139,6 @@ struct oz_app_hdr {
 /* Values for app_id.
  */
 #define OZ_APPID_USB				0x1
-#define OZ_APPID_UNUSED1			0x2
-#define OZ_APPID_UNUSED2			0x3
 #define OZ_APPID_SERIAL				0x4
 #define OZ_APPID_MAX				OZ_APPID_SERIAL
 #define OZ_NB_APPS				(OZ_APPID_MAX+1)
diff --git a/drivers/staging/ozwpan/ozusbsvc.c b/drivers/staging/ozwpan/ozusbsvc.c
index edd44c4..db4a387 100644
--- a/drivers/staging/ozwpan/ozusbsvc.c
+++ b/drivers/staging/ozwpan/ozusbsvc.c
@@ -73,12 +73,12 @@ int oz_usb_start(struct oz_pd *pd, int resume)
 	 * If it does already have one then destroy the one we have just
 	 * created.
 	 */
-	spin_lock_bh(&pd->app_lock[OZ_APPID_USB-1]);
-	old_ctx = pd->app_ctx[OZ_APPID_USB-1];
+	spin_lock_bh(&pd->app_lock[OZ_APPID_USB]);
+	old_ctx = pd->app_ctx[OZ_APPID_USB];
 	if (old_ctx == NULL)
-		pd->app_ctx[OZ_APPID_USB-1] = usb_ctx;
-	oz_usb_get(pd->app_ctx[OZ_APPID_USB-1]);
-	spin_unlock_bh(&pd->app_lock[OZ_APPID_USB-1]);
+		pd->app_ctx[OZ_APPID_USB] = usb_ctx;
+	oz_usb_get(pd->app_ctx[OZ_APPID_USB]);
+	spin_unlock_bh(&pd->app_lock[OZ_APPID_USB]);
 	if (old_ctx) {
 		oz_dbg(ON, "Already have USB context\n");
 		kfree(usb_ctx);
@@ -99,9 +99,9 @@ int oz_usb_start(struct oz_pd *pd, int resume)
 		usb_ctx->hport = oz_hcd_pd_arrived(usb_ctx);
 		if (usb_ctx->hport == NULL) {
 			oz_dbg(ON, "USB hub returned null port\n");
-			spin_lock_bh(&pd->app_lock[OZ_APPID_USB-1]);
-			pd->app_ctx[OZ_APPID_USB-1] = NULL;
-			spin_unlock_bh(&pd->app_lock[OZ_APPID_USB-1]);
+			spin_lock_bh(&pd->app_lock[OZ_APPID_USB]);
+			pd->app_ctx[OZ_APPID_USB] = NULL;
+			spin_unlock_bh(&pd->app_lock[OZ_APPID_USB]);
 			oz_usb_put(usb_ctx);
 			rc = -1;
 		}
@@ -122,10 +122,10 @@ void oz_usb_stop(struct oz_pd *pd, int pause)
 		oz_dbg(ON, "USB service paused\n");
 		return;
 	}
-	spin_lock_bh(&pd->app_lock[OZ_APPID_USB-1]);
-	usb_ctx = (struct oz_usb_ctx *)pd->app_ctx[OZ_APPID_USB-1];
-	pd->app_ctx[OZ_APPID_USB-1] = NULL;
-	spin_unlock_bh(&pd->app_lock[OZ_APPID_USB-1]);
+	spin_lock_bh(&pd->app_lock[OZ_APPID_USB]);
+	usb_ctx = (struct oz_usb_ctx *) pd->app_ctx[OZ_APPID_USB];
+	pd->app_ctx[OZ_APPID_USB] = NULL;
+	spin_unlock_bh(&pd->app_lock[OZ_APPID_USB]);
 	if (usb_ctx) {
 		struct timespec ts, now;
 		getnstimeofday(&ts);
@@ -187,11 +187,11 @@ int oz_usb_heartbeat(struct oz_pd *pd)
 	struct oz_usb_ctx *usb_ctx;
 	int rc = 0;
 
-	spin_lock_bh(&pd->app_lock[OZ_APPID_USB-1]);
-	usb_ctx = (struct oz_usb_ctx *)pd->app_ctx[OZ_APPID_USB-1];
+	spin_lock_bh(&pd->app_lock[OZ_APPID_USB]);
+	usb_ctx = (struct oz_usb_ctx *) pd->app_ctx[OZ_APPID_USB];
 	if (usb_ctx)
 		oz_usb_get(usb_ctx);
-	spin_unlock_bh(&pd->app_lock[OZ_APPID_USB-1]);
+	spin_unlock_bh(&pd->app_lock[OZ_APPID_USB]);
 	if (usb_ctx == NULL)
 		return rc;
 	if (usb_ctx->stopped)
diff --git a/drivers/staging/ozwpan/ozusbsvc1.c b/drivers/staging/ozwpan/ozusbsvc1.c
index f32d014..12bb236 100644
--- a/drivers/staging/ozwpan/ozusbsvc1.c
+++ b/drivers/staging/ozwpan/ozusbsvc1.c
@@ -364,11 +364,11 @@ void oz_usb_rx(struct oz_pd *pd, struct oz_elt *elt)
 	struct oz_usb_hdr *usb_hdr = (struct oz_usb_hdr *)(elt + 1);
 	struct oz_usb_ctx *usb_ctx;
 
-	spin_lock_bh(&pd->app_lock[OZ_APPID_USB-1]);
-	usb_ctx = (struct oz_usb_ctx *)pd->app_ctx[OZ_APPID_USB-1];
+	spin_lock_bh(&pd->app_lock[OZ_APPID_USB]);
+	usb_ctx = (struct oz_usb_ctx *)pd->app_ctx[OZ_APPID_USB];
 	if (usb_ctx)
 		oz_usb_get(usb_ctx);
-	spin_unlock_bh(&pd->app_lock[OZ_APPID_USB-1]);
+	spin_unlock_bh(&pd->app_lock[OZ_APPID_USB]);
 	if (usb_ctx == NULL)
 		return; /* Context has gone so nothing to do. */
 	if (usb_ctx->stopped)
@@ -434,11 +434,11 @@ void oz_usb_farewell(struct oz_pd *pd, u8 ep_num, u8 *data, u8 len)
 {
 	struct oz_usb_ctx *usb_ctx;
 
-	spin_lock_bh(&pd->app_lock[OZ_APPID_USB-1]);
-	usb_ctx = (struct oz_usb_ctx *)pd->app_ctx[OZ_APPID_USB-1];
+	spin_lock_bh(&pd->app_lock[OZ_APPID_USB]);
+	usb_ctx = (struct oz_usb_ctx *)pd->app_ctx[OZ_APPID_USB];
 	if (usb_ctx)
 		oz_usb_get(usb_ctx);
-	spin_unlock_bh(&pd->app_lock[OZ_APPID_USB-1]);
+	spin_unlock_bh(&pd->app_lock[OZ_APPID_USB]);
 	if (usb_ctx == NULL)
 		return; /* Context has gone so nothing to do. */
 	if (!usb_ctx->stopped) {
-- 
1.9.1

Re: [PATCH 06/10] staging: ozwpan: Simplify app interface

[Dan Carpenter]

On Mon, Aug 04, 2014 at 02:54:52PM +0200, Christoph Jaeger wrote:
> Simplify the somewhat overcomplicated application interface; improves
> readability and saves a bunch of lines.
> 
> Use designated struct initializers for clarity.

I was worried this would change the API but it doesn't.  The patch looks
ok.

Reviewed-by: Dan Carpenter <dan.carpenter@oracle.com>

regards,
dan carpenter

[PATCH 07/10] staging: ozwpan: Use slab cache for oz_urb_link allocation

[Christoph Jaeger]

Use a slab cache rather than rolling our own free list.

Signed-off-by: Christoph Jaeger <email@christophjaeger.info>
---
 drivers/staging/ozwpan/ozhcd.c | 70 ++++++++----------------------------------
 1 file changed, 12 insertions(+), 58 deletions(-)

diff --git a/drivers/staging/ozwpan/ozhcd.c b/drivers/staging/ozwpan/ozhcd.c
index 30bd928..3b603c5 100644
--- a/drivers/staging/ozwpan/ozhcd.c
+++ b/drivers/staging/ozwpan/ozhcd.c
@@ -45,10 +45,6 @@
  */
 #define OZ_PLAT_DEV_NAME	"ozwpan"
 
-/* Maximum number of free urb links that can be kept in the pool.
- */
-#define OZ_MAX_LINK_POOL_SIZE	16
-
 /* Get endpoint object from the containing link.
  */
 #define ep_from_link(__e) container_of((__e), struct oz_endpoint, link)
@@ -75,6 +71,8 @@ struct oz_urb_link {
 	unsigned submit_counter;
 };
 
+static struct kmem_cache *oz_urb_link_cache;
+
 /* Holds state information about a USB endpoint.
  */
 #define OZ_EP_BUFFER_SIZE_ISOC  (1024 * 24)
@@ -198,9 +196,6 @@ static struct platform_device *g_plat_dev;
 static struct oz_hcd *g_ozhcd;
 static DEFINE_SPINLOCK(g_hcdlock);	/* Guards g_ozhcd. */
 static const char g_hcd_name[] = "Ozmo WPAN";
-static struct list_head *g_link_pool;
-static int g_link_pool_size;
-static DEFINE_SPINLOCK(g_link_lock);
 static DEFINE_SPINLOCK(g_tasklet_lock);
 static struct tasklet_struct g_urb_process_tasklet;
 static struct tasklet_struct g_urb_cancel_tasklet;
@@ -265,68 +260,22 @@ static int oz_get_port_from_addr(struct oz_hcd *ozhcd, u8 bus_addr)
 }
 
 /*
- * Allocates an urb link, first trying the pool but going to heap if empty.
  * Context: any
  */
 static struct oz_urb_link *oz_alloc_urb_link(void)
 {
-	struct oz_urb_link *urbl = NULL;
-	unsigned long irq_state;
-
-	spin_lock_irqsave(&g_link_lock, irq_state);
-	if (g_link_pool) {
-		urbl = container_of(g_link_pool, struct oz_urb_link, link);
-		g_link_pool = urbl->link.next;
-		--g_link_pool_size;
-	}
-	spin_unlock_irqrestore(&g_link_lock, irq_state);
-	if (urbl == NULL)
-		urbl = kmalloc(sizeof(struct oz_urb_link), GFP_ATOMIC);
-	return urbl;
+	return kmem_cache_alloc(oz_urb_link_cache, GFP_ATOMIC);
 }
 
 /*
- * Frees an urb link by putting it in the pool if there is enough space or
- * deallocating it to heap otherwise.
  * Context: any
  */
 static void oz_free_urb_link(struct oz_urb_link *urbl)
 {
-	if (urbl) {
-		unsigned long irq_state;
-
-		spin_lock_irqsave(&g_link_lock, irq_state);
-		if (g_link_pool_size < OZ_MAX_LINK_POOL_SIZE) {
-			urbl->link.next = g_link_pool;
-			g_link_pool = &urbl->link;
-			urbl = NULL;
-			g_link_pool_size++;
-		}
-		spin_unlock_irqrestore(&g_link_lock, irq_state);
-		kfree(urbl);
-	}
-}
-
-/*
- * Deallocates all the urb links in the pool.
- * Context: unknown
- */
-static void oz_empty_link_pool(void)
-{
-	struct list_head *e;
-	unsigned long irq_state;
+	if (unlikely(!urbl))
+		return;
 
-	spin_lock_irqsave(&g_link_lock, irq_state);
-	e = g_link_pool;
-	g_link_pool = NULL;
-	g_link_pool_size = 0;
-	spin_unlock_irqrestore(&g_link_lock, irq_state);
-	while (e) {
-		struct oz_urb_link *urbl =
-			container_of(e, struct oz_urb_link, link);
-		e = e->next;
-		kfree(urbl);
-	}
+	kmem_cache_free(oz_urb_link_cache, urbl);
 }
 
 /*
@@ -2311,7 +2260,6 @@ static int oz_plat_remove(struct platform_device *dev)
 	oz_dbg(ON, "Removing hcd\n");
 	usb_remove_hcd(hcd);
 	usb_put_hcd(hcd);
-	oz_empty_link_pool();
 	return 0;
 }
 
@@ -2341,6 +2289,11 @@ int oz_hcd_init(void)
 
 	if (usb_disabled())
 		return -ENODEV;
+
+	oz_urb_link_cache = KMEM_CACHE(oz_urb_link, 0);
+	if (unlikely(!oz_urb_link_cache))
+		return -ENOMEM;
+
 	tasklet_init(&g_urb_process_tasklet, oz_urb_process_tasklet, 0);
 	tasklet_init(&g_urb_cancel_tasklet, oz_urb_cancel_tasklet, 0);
 	err = platform_driver_register(&g_oz_plat_drv);
@@ -2380,4 +2333,5 @@ void oz_hcd_term(void)
 	platform_device_unregister(g_plat_dev);
 	platform_driver_unregister(&g_oz_plat_drv);
 	oz_dbg(ON, "Pending urbs:%d\n", atomic_read(&g_pending_urbs));
+	kmem_cache_destroy(oz_urb_link_cache);
 }
-- 
1.9.1

Re: [PATCH 07/10] staging: ozwpan: Use slab cache for oz_urb_link allocation

[Dan Carpenter]

On Mon, Aug 04, 2014 at 02:54:53PM +0200, Christoph Jaeger wrote:
> @@ -2341,6 +2289,11 @@ int oz_hcd_init(void)
>  
>  	if (usb_disabled())
>  		return -ENODEV;
> +
> +	oz_urb_link_cache = KMEM_CACHE(oz_urb_link, 0);
> +	if (unlikely(!oz_urb_link_cache))
> +		return -ENOMEM;

Don't put unlikely() calls in driver code.  It just makes it messy for
no reason.  "Oooo!  I can modprobe/rmmod this driver 1000000 times in a
row and it speeds it up .0003 seconds because I added an unlikely tag!"

regards,
dan carpenter

[PATCH 07/10 v2] staging: ozwpan: Use slab cache for oz_urb_link allocation

[Christoph Jaeger]

Use a slab cache rather than rolling our own free list.

Signed-off-by: Christoph Jaeger <email@christophjaeger.info>
---
v2: Don't use likely()/unlikely().

 drivers/staging/ozwpan/ozhcd.c | 70 ++++++++----------------------------------
 1 file changed, 12 insertions(+), 58 deletions(-)

diff --git a/drivers/staging/ozwpan/ozhcd.c b/drivers/staging/ozwpan/ozhcd.c
index 30bd928..1142f57 100644
--- a/drivers/staging/ozwpan/ozhcd.c
+++ b/drivers/staging/ozwpan/ozhcd.c
@@ -45,10 +45,6 @@
  */
 #define OZ_PLAT_DEV_NAME	"ozwpan"
 
-/* Maximum number of free urb links that can be kept in the pool.
- */
-#define OZ_MAX_LINK_POOL_SIZE	16
-
 /* Get endpoint object from the containing link.
  */
 #define ep_from_link(__e) container_of((__e), struct oz_endpoint, link)
@@ -75,6 +71,8 @@ struct oz_urb_link {
 	unsigned submit_counter;
 };
 
+static struct kmem_cache *oz_urb_link_cache;
+
 /* Holds state information about a USB endpoint.
  */
 #define OZ_EP_BUFFER_SIZE_ISOC  (1024 * 24)
@@ -198,9 +196,6 @@ static struct platform_device *g_plat_dev;
 static struct oz_hcd *g_ozhcd;
 static DEFINE_SPINLOCK(g_hcdlock);	/* Guards g_ozhcd. */
 static const char g_hcd_name[] = "Ozmo WPAN";
-static struct list_head *g_link_pool;
-static int g_link_pool_size;
-static DEFINE_SPINLOCK(g_link_lock);
 static DEFINE_SPINLOCK(g_tasklet_lock);
 static struct tasklet_struct g_urb_process_tasklet;
 static struct tasklet_struct g_urb_cancel_tasklet;
@@ -265,68 +260,22 @@ static int oz_get_port_from_addr(struct oz_hcd *ozhcd, u8 bus_addr)
 }
 
 /*
- * Allocates an urb link, first trying the pool but going to heap if empty.
  * Context: any
  */
 static struct oz_urb_link *oz_alloc_urb_link(void)
 {
-	struct oz_urb_link *urbl = NULL;
-	unsigned long irq_state;
-
-	spin_lock_irqsave(&g_link_lock, irq_state);
-	if (g_link_pool) {
-		urbl = container_of(g_link_pool, struct oz_urb_link, link);
-		g_link_pool = urbl->link.next;
-		--g_link_pool_size;
-	}
-	spin_unlock_irqrestore(&g_link_lock, irq_state);
-	if (urbl == NULL)
-		urbl = kmalloc(sizeof(struct oz_urb_link), GFP_ATOMIC);
-	return urbl;
+	return kmem_cache_alloc(oz_urb_link_cache, GFP_ATOMIC);
 }
 
 /*
- * Frees an urb link by putting it in the pool if there is enough space or
- * deallocating it to heap otherwise.
  * Context: any
  */
 static void oz_free_urb_link(struct oz_urb_link *urbl)
 {
-	if (urbl) {
-		unsigned long irq_state;
-
-		spin_lock_irqsave(&g_link_lock, irq_state);
-		if (g_link_pool_size < OZ_MAX_LINK_POOL_SIZE) {
-			urbl->link.next = g_link_pool;
-			g_link_pool = &urbl->link;
-			urbl = NULL;
-			g_link_pool_size++;
-		}
-		spin_unlock_irqrestore(&g_link_lock, irq_state);
-		kfree(urbl);
-	}
-}
-
-/*
- * Deallocates all the urb links in the pool.
- * Context: unknown
- */
-static void oz_empty_link_pool(void)
-{
-	struct list_head *e;
-	unsigned long irq_state;
+	if (!urbl)
+		return;
 
-	spin_lock_irqsave(&g_link_lock, irq_state);
-	e = g_link_pool;
-	g_link_pool = NULL;
-	g_link_pool_size = 0;
-	spin_unlock_irqrestore(&g_link_lock, irq_state);
-	while (e) {
-		struct oz_urb_link *urbl =
-			container_of(e, struct oz_urb_link, link);
-		e = e->next;
-		kfree(urbl);
-	}
+	kmem_cache_free(oz_urb_link_cache, urbl);
 }
 
 /*
@@ -2311,7 +2260,6 @@ static int oz_plat_remove(struct platform_device *dev)
 	oz_dbg(ON, "Removing hcd\n");
 	usb_remove_hcd(hcd);
 	usb_put_hcd(hcd);
-	oz_empty_link_pool();
 	return 0;
 }
 
@@ -2341,6 +2289,11 @@ int oz_hcd_init(void)
 
 	if (usb_disabled())
 		return -ENODEV;
+
+	oz_urb_link_cache = KMEM_CACHE(oz_urb_link, 0);
+	if (!oz_urb_link_cache)
+		return -ENOMEM;
+
 	tasklet_init(&g_urb_process_tasklet, oz_urb_process_tasklet, 0);
 	tasklet_init(&g_urb_cancel_tasklet, oz_urb_cancel_tasklet, 0);
 	err = platform_driver_register(&g_oz_plat_drv);
@@ -2380,4 +2333,5 @@ void oz_hcd_term(void)
 	platform_device_unregister(g_plat_dev);
 	platform_driver_unregister(&g_oz_plat_drv);
 	oz_dbg(ON, "Pending urbs:%d\n", atomic_read(&g_pending_urbs));
+	kmem_cache_destroy(oz_urb_link_cache);
 }
-- 
1.9.1

[PATCH 08/10] staging: ozwpan: Use slab cache for oz_elt_info allocation

[Christoph Jaeger]

Use a slab cache rather than rolling our own free list.

Signed-off-by: Christoph Jaeger <email@christophjaeger.info>
---
 drivers/staging/ozwpan/ozeltbuf.c | 70 +++------------------------------------
 drivers/staging/ozwpan/ozeltbuf.h |  5 ---
 drivers/staging/ozwpan/ozpd.c     |  2 --
 drivers/staging/ozwpan/ozpd.h     |  2 ++
 drivers/staging/ozwpan/ozproto.c  |  9 +++++
 drivers/staging/ozwpan/ozproto.h  |  2 ++
 6 files changed, 17 insertions(+), 73 deletions(-)

diff --git a/drivers/staging/ozwpan/ozeltbuf.c b/drivers/staging/ozwpan/ozeltbuf.c
index f6e6481..81580cb 100644
--- a/drivers/staging/ozwpan/ozeltbuf.c
+++ b/drivers/staging/ozwpan/ozeltbuf.c
@@ -10,9 +10,6 @@
 #include "ozeltbuf.h"
 #include "ozpd.h"
 
-#define OZ_ELT_INFO_MAGIC_USED	0x35791057
-#define OZ_ELT_INFO_MAGIC_FREE	0x78940102
-
 /*
  * Context: softirq-serialized
  */
@@ -22,7 +19,6 @@ void oz_elt_buf_init(struct oz_elt_buf *buf)
 	INIT_LIST_HEAD(&buf->stream_list);
 	INIT_LIST_HEAD(&buf->order_list);
 	INIT_LIST_HEAD(&buf->isoc_list);
-	buf->max_free_elts = 32;
 	spin_lock_init(&buf->lock);
 }
 
@@ -49,14 +45,6 @@ void oz_elt_buf_term(struct oz_elt_buf *buf)
 			kfree(ei);
 		}
 	}
-	/* Free any elelment in the pool. */
-	while (buf->elt_pool) {
-		struct oz_elt_info *ei =
-			container_of(buf->elt_pool, struct oz_elt_info, link);
-		buf->elt_pool = buf->elt_pool->next;
-		kfree(ei);
-	}
-	buf->free_elts = 0;
 }
 
 /*
@@ -66,27 +54,8 @@ struct oz_elt_info *oz_elt_info_alloc(struct oz_elt_buf *buf)
 {
 	struct oz_elt_info *ei;
 
-	spin_lock_bh(&buf->lock);
-	if (buf->free_elts && buf->elt_pool) {
-		ei = container_of(buf->elt_pool, struct oz_elt_info, link);
-		buf->elt_pool = ei->link.next;
-		buf->free_elts--;
-		spin_unlock_bh(&buf->lock);
-		if (ei->magic != OZ_ELT_INFO_MAGIC_FREE) {
-			oz_dbg(ON, "%s: ei with bad magic: 0x%x\n",
-			       __func__, ei->magic);
-		}
-	} else {
-		spin_unlock_bh(&buf->lock);
-		ei = kmalloc(sizeof(struct oz_elt_info), GFP_ATOMIC);
-	}
-	if (ei) {
-		ei->flags = 0;
-		ei->app_id = 0;
-		ei->callback = NULL;
-		ei->context = 0;
-		ei->stream = NULL;
-		ei->magic = OZ_ELT_INFO_MAGIC_USED;
+	ei = kmem_cache_zalloc(oz_elt_info_cache, GFP_ATOMIC);
+	if (likely(ei)) {
 		INIT_LIST_HEAD(&ei->link);
 		INIT_LIST_HEAD(&ei->link_order);
 	}
@@ -99,17 +68,8 @@ struct oz_elt_info *oz_elt_info_alloc(struct oz_elt_buf *buf)
  */
 void oz_elt_info_free(struct oz_elt_buf *buf, struct oz_elt_info *ei)
 {
-	if (ei) {
-		if (ei->magic == OZ_ELT_INFO_MAGIC_USED) {
-			buf->free_elts++;
-			ei->link.next = buf->elt_pool;
-			buf->elt_pool = &ei->link;
-			ei->magic = OZ_ELT_INFO_MAGIC_FREE;
-		} else {
-			oz_dbg(ON, "%s: bad magic ei: %p magic: 0x%x\n",
-			       __func__, ei, ei->magic);
-		}
-	}
+	if (likely(ei))
+		kmem_cache_free(oz_elt_info_cache, ei);
 }
 
 /*------------------------------------------------------------------------------
@@ -313,25 +273,3 @@ int oz_are_elts_available(struct oz_elt_buf *buf)
 {
 	return buf->order_list.next != &buf->order_list;
 }
-
-void oz_trim_elt_pool(struct oz_elt_buf *buf)
-{
-	struct list_head *free = NULL;
-	struct list_head *e;
-
-	spin_lock_bh(&buf->lock);
-	while (buf->free_elts > buf->max_free_elts) {
-		e = buf->elt_pool;
-		buf->elt_pool = e->next;
-		e->next = free;
-		free = e;
-		buf->free_elts--;
-	}
-	spin_unlock_bh(&buf->lock);
-	while (free) {
-		struct oz_elt_info *ei =
-			container_of(free, struct oz_elt_info, link);
-		free = free->next;
-		kfree(ei);
-	}
-}
diff --git a/drivers/staging/ozwpan/ozeltbuf.h b/drivers/staging/ozwpan/ozeltbuf.h
index 3846432..f09f5fe 100644
--- a/drivers/staging/ozwpan/ozeltbuf.h
+++ b/drivers/staging/ozwpan/ozeltbuf.h
@@ -34,7 +34,6 @@ struct oz_elt_info {
 	struct oz_elt_stream *stream;
 	u8 data[sizeof(struct oz_elt) + OZ_MAX_ELT_PAYLOAD];
 	int length;
-	unsigned magic;
 };
 /* Flags values */
 #define OZ_EI_F_MARKED		0x1
@@ -44,9 +43,6 @@ struct oz_elt_buf {
 	struct list_head stream_list;
 	struct list_head order_list;
 	struct list_head isoc_list;
-	struct list_head *elt_pool;
-	int free_elts;
-	int max_free_elts;
 	u8 tx_seq_num[OZ_NB_APPS];
 };
 
@@ -64,7 +60,6 @@ int oz_queue_elt_info(struct oz_elt_buf *buf, u8 isoc, u8 id,
 int oz_select_elts_for_tx(struct oz_elt_buf *buf, u8 isoc, unsigned *len,
 		unsigned max_len, struct list_head *list);
 int oz_are_elts_available(struct oz_elt_buf *buf);
-void oz_trim_elt_pool(struct oz_elt_buf *buf);
 
 #endif /* _OZELTBUF_H */
 
diff --git a/drivers/staging/ozwpan/ozpd.c b/drivers/staging/ozwpan/ozpd.c
index 6c4b13f..c6fddb8 100644
--- a/drivers/staging/ozwpan/ozpd.c
+++ b/drivers/staging/ozwpan/ozpd.c
@@ -504,8 +504,6 @@ static void oz_retire_frame(struct oz_pd *pd, struct oz_tx_frame *f)
 		spin_unlock_bh(&pd->elt_buff.lock);
 	}
 	oz_tx_frame_free(pd, f);
-	if (pd->elt_buff.free_elts > pd->elt_buff.max_free_elts)
-		oz_trim_elt_pool(&pd->elt_buff);
 }
 
 /*
diff --git a/drivers/staging/ozwpan/ozpd.h b/drivers/staging/ozwpan/ozpd.h
index 3b3b3ce..43a26ea 100644
--- a/drivers/staging/ozwpan/ozpd.h
+++ b/drivers/staging/ozwpan/ozpd.h
@@ -130,4 +130,6 @@ void oz_handle_app_elt(struct oz_pd *pd, u8 app_id, struct oz_elt *elt);
 void oz_apps_init(void);
 void oz_apps_term(void);
 
+extern struct kmem_cache *oz_elt_info_cache;
+
 #endif /* Sentry */
diff --git a/drivers/staging/ozwpan/ozproto.c b/drivers/staging/ozwpan/ozproto.c
index 549fe7f..00d245b 100644
--- a/drivers/staging/ozwpan/ozproto.c
+++ b/drivers/staging/ozwpan/ozproto.c
@@ -11,6 +11,7 @@
 #include <linux/etherdevice.h>
 #include <linux/errno.h>
 #include <linux/ieee80211.h>
+#include <linux/slab.h>
 #include "ozdbg.h"
 #include "ozprotocol.h"
 #include "ozeltbuf.h"
@@ -51,6 +52,8 @@ static u8 g_session_id;
 static u16 g_apps = 0x1;
 static int g_processing_rx;
 
+struct kmem_cache *oz_elt_info_cache;
+
 /*
  * Context: softirq-serialized
  */
@@ -479,6 +482,8 @@ void oz_protocol_term(void)
 	}
 	spin_unlock_bh(&g_polling_lock);
 	oz_dbg(ON, "Protocol stopped\n");
+
+	kmem_cache_destroy(oz_elt_info_cache);
 }
 
 /*
@@ -762,6 +767,10 @@ static char *oz_get_next_device_name(char *s, char *dname, int max_size)
  */
 int oz_protocol_init(char *devs)
 {
+	oz_elt_info_cache = KMEM_CACHE(oz_elt_info, 0);
+	if (unlikely(!oz_elt_info_cache))
+		return -ENOMEM;
+
 	skb_queue_head_init(&g_rx_queue);
 	if (devs[0] == '*') {
 		oz_binding_add(NULL);
diff --git a/drivers/staging/ozwpan/ozproto.h b/drivers/staging/ozwpan/ozproto.h
index f1d30c4..b0f7459 100644
--- a/drivers/staging/ozwpan/ozproto.h
+++ b/drivers/staging/ozwpan/ozproto.h
@@ -65,4 +65,6 @@ enum hrtimer_restart oz_pd_timeout_event(struct hrtimer *timer);
 int oz_get_pd_status_list(char *pd_list, int max_count);
 int oz_get_binding_list(char *buf, int max_if);
 
+extern struct kmem_cache *oz_elt_info_cache;
+
 #endif /* _OZPROTO_H */
-- 
1.9.1

[PATCH 08/10 v2] staging: ozwpan: Use slab cache for oz_elt_info allocation

[Christoph Jaeger]

Use a slab cache rather than rolling our own free list.

Signed-off-by: Christoph Jaeger <email@christophjaeger.info>
---
v2: Don't use likely()/unlikely().

 drivers/staging/ozwpan/ozeltbuf.c | 68 ++-------------------------------------
 drivers/staging/ozwpan/ozeltbuf.h |  5 ---
 drivers/staging/ozwpan/ozpd.c     |  2 --
 drivers/staging/ozwpan/ozpd.h     |  2 ++
 drivers/staging/ozwpan/ozproto.c  |  9 ++++++
 drivers/staging/ozwpan/ozproto.h  |  2 ++
 6 files changed, 16 insertions(+), 72 deletions(-)

diff --git a/drivers/staging/ozwpan/ozeltbuf.c b/drivers/staging/ozwpan/ozeltbuf.c
index f6e6481..389ab1a 100644
--- a/drivers/staging/ozwpan/ozeltbuf.c
+++ b/drivers/staging/ozwpan/ozeltbuf.c
@@ -10,9 +10,6 @@
 #include "ozeltbuf.h"
 #include "ozpd.h"
 
-#define OZ_ELT_INFO_MAGIC_USED	0x35791057
-#define OZ_ELT_INFO_MAGIC_FREE	0x78940102
-
 /*
  * Context: softirq-serialized
  */
@@ -22,7 +19,6 @@ void oz_elt_buf_init(struct oz_elt_buf *buf)
 	INIT_LIST_HEAD(&buf->stream_list);
 	INIT_LIST_HEAD(&buf->order_list);
 	INIT_LIST_HEAD(&buf->isoc_list);
-	buf->max_free_elts = 32;
 	spin_lock_init(&buf->lock);
 }
 
@@ -49,14 +45,6 @@ void oz_elt_buf_term(struct oz_elt_buf *buf)
 			kfree(ei);
 		}
 	}
-	/* Free any elelment in the pool. */
-	while (buf->elt_pool) {
-		struct oz_elt_info *ei =
-			container_of(buf->elt_pool, struct oz_elt_info, link);
-		buf->elt_pool = buf->elt_pool->next;
-		kfree(ei);
-	}
-	buf->free_elts = 0;
 }
 
 /*
@@ -66,27 +54,8 @@ struct oz_elt_info *oz_elt_info_alloc(struct oz_elt_buf *buf)
 {
 	struct oz_elt_info *ei;
 
-	spin_lock_bh(&buf->lock);
-	if (buf->free_elts && buf->elt_pool) {
-		ei = container_of(buf->elt_pool, struct oz_elt_info, link);
-		buf->elt_pool = ei->link.next;
-		buf->free_elts--;
-		spin_unlock_bh(&buf->lock);
-		if (ei->magic != OZ_ELT_INFO_MAGIC_FREE) {
-			oz_dbg(ON, "%s: ei with bad magic: 0x%x\n",
-			       __func__, ei->magic);
-		}
-	} else {
-		spin_unlock_bh(&buf->lock);
-		ei = kmalloc(sizeof(struct oz_elt_info), GFP_ATOMIC);
-	}
+	ei = kmem_cache_zalloc(oz_elt_info_cache, GFP_ATOMIC);
 	if (ei) {
-		ei->flags = 0;
-		ei->app_id = 0;
-		ei->callback = NULL;
-		ei->context = 0;
-		ei->stream = NULL;
-		ei->magic = OZ_ELT_INFO_MAGIC_USED;
 		INIT_LIST_HEAD(&ei->link);
 		INIT_LIST_HEAD(&ei->link_order);
 	}
@@ -99,17 +68,8 @@ struct oz_elt_info *oz_elt_info_alloc(struct oz_elt_buf *buf)
  */
 void oz_elt_info_free(struct oz_elt_buf *buf, struct oz_elt_info *ei)
 {
-	if (ei) {
-		if (ei->magic == OZ_ELT_INFO_MAGIC_USED) {
-			buf->free_elts++;
-			ei->link.next = buf->elt_pool;
-			buf->elt_pool = &ei->link;
-			ei->magic = OZ_ELT_INFO_MAGIC_FREE;
-		} else {
-			oz_dbg(ON, "%s: bad magic ei: %p magic: 0x%x\n",
-			       __func__, ei, ei->magic);
-		}
-	}
+	if (ei)
+		kmem_cache_free(oz_elt_info_cache, ei);
 }
 
 /*------------------------------------------------------------------------------
@@ -313,25 +273,3 @@ int oz_are_elts_available(struct oz_elt_buf *buf)
 {
 	return buf->order_list.next != &buf->order_list;
 }
-
-void oz_trim_elt_pool(struct oz_elt_buf *buf)
-{
-	struct list_head *free = NULL;
-	struct list_head *e;
-
-	spin_lock_bh(&buf->lock);
-	while (buf->free_elts > buf->max_free_elts) {
-		e = buf->elt_pool;
-		buf->elt_pool = e->next;
-		e->next = free;
-		free = e;
-		buf->free_elts--;
-	}
-	spin_unlock_bh(&buf->lock);
-	while (free) {
-		struct oz_elt_info *ei =
-			container_of(free, struct oz_elt_info, link);
-		free = free->next;
-		kfree(ei);
-	}
-}
diff --git a/drivers/staging/ozwpan/ozeltbuf.h b/drivers/staging/ozwpan/ozeltbuf.h
index 3846432..f09f5fe 100644
--- a/drivers/staging/ozwpan/ozeltbuf.h
+++ b/drivers/staging/ozwpan/ozeltbuf.h
@@ -34,7 +34,6 @@ struct oz_elt_info {
 	struct oz_elt_stream *stream;
 	u8 data[sizeof(struct oz_elt) + OZ_MAX_ELT_PAYLOAD];
 	int length;
-	unsigned magic;
 };
 /* Flags values */
 #define OZ_EI_F_MARKED		0x1
@@ -44,9 +43,6 @@ struct oz_elt_buf {
 	struct list_head stream_list;
 	struct list_head order_list;
 	struct list_head isoc_list;
-	struct list_head *elt_pool;
-	int free_elts;
-	int max_free_elts;
 	u8 tx_seq_num[OZ_NB_APPS];
 };
 
@@ -64,7 +60,6 @@ int oz_queue_elt_info(struct oz_elt_buf *buf, u8 isoc, u8 id,
 int oz_select_elts_for_tx(struct oz_elt_buf *buf, u8 isoc, unsigned *len,
 		unsigned max_len, struct list_head *list);
 int oz_are_elts_available(struct oz_elt_buf *buf);
-void oz_trim_elt_pool(struct oz_elt_buf *buf);
 
 #endif /* _OZELTBUF_H */
 
diff --git a/drivers/staging/ozwpan/ozpd.c b/drivers/staging/ozwpan/ozpd.c
index 6c4b13f..c6fddb8 100644
--- a/drivers/staging/ozwpan/ozpd.c
+++ b/drivers/staging/ozwpan/ozpd.c
@@ -504,8 +504,6 @@ static void oz_retire_frame(struct oz_pd *pd, struct oz_tx_frame *f)
 		spin_unlock_bh(&pd->elt_buff.lock);
 	}
 	oz_tx_frame_free(pd, f);
-	if (pd->elt_buff.free_elts > pd->elt_buff.max_free_elts)
-		oz_trim_elt_pool(&pd->elt_buff);
 }
 
 /*
diff --git a/drivers/staging/ozwpan/ozpd.h b/drivers/staging/ozwpan/ozpd.h
index 3b3b3ce..43a26ea 100644
--- a/drivers/staging/ozwpan/ozpd.h
+++ b/drivers/staging/ozwpan/ozpd.h
@@ -130,4 +130,6 @@ void oz_handle_app_elt(struct oz_pd *pd, u8 app_id, struct oz_elt *elt);
 void oz_apps_init(void);
 void oz_apps_term(void);
 
+extern struct kmem_cache *oz_elt_info_cache;
+
 #endif /* Sentry */
diff --git a/drivers/staging/ozwpan/ozproto.c b/drivers/staging/ozwpan/ozproto.c
index 549fe7f..b592e96 100644
--- a/drivers/staging/ozwpan/ozproto.c
+++ b/drivers/staging/ozwpan/ozproto.c
@@ -11,6 +11,7 @@
 #include <linux/etherdevice.h>
 #include <linux/errno.h>
 #include <linux/ieee80211.h>
+#include <linux/slab.h>
 #include "ozdbg.h"
 #include "ozprotocol.h"
 #include "ozeltbuf.h"
@@ -51,6 +52,8 @@ static u8 g_session_id;
 static u16 g_apps = 0x1;
 static int g_processing_rx;
 
+struct kmem_cache *oz_elt_info_cache;
+
 /*
  * Context: softirq-serialized
  */
@@ -479,6 +482,8 @@ void oz_protocol_term(void)
 	}
 	spin_unlock_bh(&g_polling_lock);
 	oz_dbg(ON, "Protocol stopped\n");
+
+	kmem_cache_destroy(oz_elt_info_cache);
 }
 
 /*
@@ -762,6 +767,10 @@ static char *oz_get_next_device_name(char *s, char *dname, int max_size)
  */
 int oz_protocol_init(char *devs)
 {
+	oz_elt_info_cache = KMEM_CACHE(oz_elt_info, 0);
+	if (!oz_elt_info_cache)
+		return -ENOMEM;
+
 	skb_queue_head_init(&g_rx_queue);
 	if (devs[0] == '*') {
 		oz_binding_add(NULL);
diff --git a/drivers/staging/ozwpan/ozproto.h b/drivers/staging/ozwpan/ozproto.h
index f1d30c4..b0f7459 100644
--- a/drivers/staging/ozwpan/ozproto.h
+++ b/drivers/staging/ozwpan/ozproto.h
@@ -65,4 +65,6 @@ enum hrtimer_restart oz_pd_timeout_event(struct hrtimer *timer);
 int oz_get_pd_status_list(char *pd_list, int max_count);
 int oz_get_binding_list(char *buf, int max_if);
 
+extern struct kmem_cache *oz_elt_info_cache;
+
 #endif /* _OZPROTO_H */
-- 
1.9.1

[PATCH 09/10] staging: ozwpan: Use slab cache for oz_tx_frame allocation

[Christoph Jaeger]

Use a slab cache rather than rolling our own free list.

Signed-off-by: Christoph Jaeger <email@christophjaeger.info>
---
 drivers/staging/ozwpan/ozpd.c    | 43 +++++++---------------------------------
 drivers/staging/ozwpan/ozpd.h    |  3 +--
 drivers/staging/ozwpan/ozproto.c |  8 ++++++++
 drivers/staging/ozwpan/ozproto.h |  1 +
 4 files changed, 17 insertions(+), 38 deletions(-)

diff --git a/drivers/staging/ozwpan/ozpd.c b/drivers/staging/ozwpan/ozpd.c
index c6fddb8..8048ea3 100644
--- a/drivers/staging/ozwpan/ozpd.c
+++ b/drivers/staging/ozwpan/ozpd.c
@@ -21,8 +21,6 @@
 #include <linux/uaccess.h>
 #include <net/psnap.h>
 
-#define OZ_MAX_TX_POOL_SIZE	6
-
 static struct oz_tx_frame *oz_tx_frame_alloc(struct oz_pd *pd);
 static void oz_tx_frame_free(struct oz_pd *pd, struct oz_tx_frame *f);
 static void oz_tx_isoc_free(struct oz_pd *pd, struct oz_tx_frame *f);
@@ -177,13 +175,6 @@ static void oz_pd_free(struct work_struct *work)
 		e = e->next;
 		kfree(fwell);
 	}
-	/* Deallocate all frames in tx pool.
-	 */
-	while (pd->tx_pool) {
-		e = pd->tx_pool;
-		pd->tx_pool = e->next;
-		kfree(container_of(e, struct oz_tx_frame, link));
-	}
 	if (pd->net_dev)
 		dev_put(pd->net_dev);
 	kfree(pd);
@@ -333,18 +324,10 @@ int oz_pd_sleep(struct oz_pd *pd)
  */
 static struct oz_tx_frame *oz_tx_frame_alloc(struct oz_pd *pd)
 {
-	struct oz_tx_frame *f = NULL;
+	struct oz_tx_frame *f;
 
-	spin_lock_bh(&pd->tx_frame_lock);
-	if (pd->tx_pool) {
-		f = container_of(pd->tx_pool, struct oz_tx_frame, link);
-		pd->tx_pool = pd->tx_pool->next;
-		pd->tx_pool_count--;
-	}
-	spin_unlock_bh(&pd->tx_frame_lock);
-	if (f == NULL)
-		f = kmalloc(sizeof(struct oz_tx_frame), GFP_ATOMIC);
-	if (f) {
+	f = kmem_cache_alloc(oz_tx_frame_cache, GFP_ATOMIC);
+	if (likely(f)) {
 		f->total_size = sizeof(struct oz_hdr);
 		INIT_LIST_HEAD(&f->link);
 		INIT_LIST_HEAD(&f->elt_list);
@@ -359,13 +342,9 @@ static void oz_tx_isoc_free(struct oz_pd *pd, struct oz_tx_frame *f)
 {
 	pd->nb_queued_isoc_frames--;
 	list_del_init(&f->link);
-	if (pd->tx_pool_count < OZ_MAX_TX_POOL_SIZE) {
-		f->link.next = pd->tx_pool;
-		pd->tx_pool = &f->link;
-		pd->tx_pool_count++;
-	} else {
-		kfree(f);
-	}
+
+	kmem_cache_free(oz_tx_frame_cache, f);
+
 	oz_dbg(TX_FRAMES, "Releasing ISOC Frame isoc_nb= %d\n",
 	       pd->nb_queued_isoc_frames);
 }
@@ -375,15 +354,7 @@ static void oz_tx_isoc_free(struct oz_pd *pd, struct oz_tx_frame *f)
  */
 static void oz_tx_frame_free(struct oz_pd *pd, struct oz_tx_frame *f)
 {
-	spin_lock_bh(&pd->tx_frame_lock);
-	if (pd->tx_pool_count < OZ_MAX_TX_POOL_SIZE) {
-		f->link.next = pd->tx_pool;
-		pd->tx_pool = &f->link;
-		pd->tx_pool_count++;
-		f = NULL;
-	}
-	spin_unlock_bh(&pd->tx_frame_lock);
-	kfree(f);
+	kmem_cache_free(oz_tx_frame_cache, f);
 }
 
 /*
diff --git a/drivers/staging/ozwpan/ozpd.h b/drivers/staging/ozwpan/ozpd.h
index 43a26ea..212fab0 100644
--- a/drivers/staging/ozwpan/ozpd.h
+++ b/drivers/staging/ozwpan/ozpd.h
@@ -90,8 +90,6 @@ struct oz_pd {
 	unsigned	max_stream_buffering;
 	int		nb_queued_frames;
 	int		nb_queued_isoc_frames;
-	struct list_head *tx_pool;
-	int		tx_pool_count;
 	spinlock_t	tx_frame_lock;
 	struct list_head *last_sent_frame;
 	struct list_head tx_queue;
@@ -131,5 +129,6 @@ void oz_apps_init(void);
 void oz_apps_term(void);
 
 extern struct kmem_cache *oz_elt_info_cache;
+extern struct kmem_cache *oz_tx_frame_cache;
 
 #endif /* Sentry */
diff --git a/drivers/staging/ozwpan/ozproto.c b/drivers/staging/ozwpan/ozproto.c
index 00d245b..c1fb442 100644
--- a/drivers/staging/ozwpan/ozproto.c
+++ b/drivers/staging/ozwpan/ozproto.c
@@ -53,6 +53,7 @@ static u16 g_apps = 0x1;
 static int g_processing_rx;
 
 struct kmem_cache *oz_elt_info_cache;
+struct kmem_cache *oz_tx_frame_cache;
 
 /*
  * Context: softirq-serialized
@@ -483,6 +484,7 @@ void oz_protocol_term(void)
 	spin_unlock_bh(&g_polling_lock);
 	oz_dbg(ON, "Protocol stopped\n");
 
+	kmem_cache_destroy(oz_tx_frame_cache);
 	kmem_cache_destroy(oz_elt_info_cache);
 }
 
@@ -771,6 +773,12 @@ int oz_protocol_init(char *devs)
 	if (unlikely(!oz_elt_info_cache))
 		return -ENOMEM;
 
+	oz_tx_frame_cache = KMEM_CACHE(oz_tx_frame, 0);
+	if (unlikely(!oz_tx_frame_cache)) {
+		kmem_cache_destroy(oz_elt_info_cache);
+		return -ENOMEM;
+	}
+
 	skb_queue_head_init(&g_rx_queue);
 	if (devs[0] == '*') {
 		oz_binding_add(NULL);
diff --git a/drivers/staging/ozwpan/ozproto.h b/drivers/staging/ozwpan/ozproto.h
index b0f7459..73cc69b 100644
--- a/drivers/staging/ozwpan/ozproto.h
+++ b/drivers/staging/ozwpan/ozproto.h
@@ -66,5 +66,6 @@ int oz_get_pd_status_list(char *pd_list, int max_count);
 int oz_get_binding_list(char *buf, int max_if);
 
 extern struct kmem_cache *oz_elt_info_cache;
+extern struct kmem_cache *oz_tx_frame_cache;
 
 #endif /* _OZPROTO_H */
-- 
1.9.1

[PATCH 09/10 v2] staging: ozwpan: Use slab cache for oz_tx_frame allocation

[Christoph Jaeger]

Use a slab cache rather than rolling our own free list.

Signed-off-by: Christoph Jaeger <email@christophjaeger.info>
---
v2: Don't use likely()/unlikely().

 drivers/staging/ozwpan/ozpd.c    | 41 ++++++----------------------------------
 drivers/staging/ozwpan/ozpd.h    |  3 +--
 drivers/staging/ozwpan/ozproto.c |  8 ++++++++
 drivers/staging/ozwpan/ozproto.h |  1 +
 4 files changed, 16 insertions(+), 37 deletions(-)

diff --git a/drivers/staging/ozwpan/ozpd.c b/drivers/staging/ozwpan/ozpd.c
index c6fddb8..e849d8a 100644
--- a/drivers/staging/ozwpan/ozpd.c
+++ b/drivers/staging/ozwpan/ozpd.c
@@ -21,8 +21,6 @@
 #include <linux/uaccess.h>
 #include <net/psnap.h>
 
-#define OZ_MAX_TX_POOL_SIZE	6
-
 static struct oz_tx_frame *oz_tx_frame_alloc(struct oz_pd *pd);
 static void oz_tx_frame_free(struct oz_pd *pd, struct oz_tx_frame *f);
 static void oz_tx_isoc_free(struct oz_pd *pd, struct oz_tx_frame *f);
@@ -177,13 +175,6 @@ static void oz_pd_free(struct work_struct *work)
 		e = e->next;
 		kfree(fwell);
 	}
-	/* Deallocate all frames in tx pool.
-	 */
-	while (pd->tx_pool) {
-		e = pd->tx_pool;
-		pd->tx_pool = e->next;
-		kfree(container_of(e, struct oz_tx_frame, link));
-	}
 	if (pd->net_dev)
 		dev_put(pd->net_dev);
 	kfree(pd);
@@ -333,17 +324,9 @@ int oz_pd_sleep(struct oz_pd *pd)
  */
 static struct oz_tx_frame *oz_tx_frame_alloc(struct oz_pd *pd)
 {
-	struct oz_tx_frame *f = NULL;
+	struct oz_tx_frame *f;
 
-	spin_lock_bh(&pd->tx_frame_lock);
-	if (pd->tx_pool) {
-		f = container_of(pd->tx_pool, struct oz_tx_frame, link);
-		pd->tx_pool = pd->tx_pool->next;
-		pd->tx_pool_count--;
-	}
-	spin_unlock_bh(&pd->tx_frame_lock);
-	if (f == NULL)
-		f = kmalloc(sizeof(struct oz_tx_frame), GFP_ATOMIC);
+	f = kmem_cache_alloc(oz_tx_frame_cache, GFP_ATOMIC);
 	if (f) {
 		f->total_size = sizeof(struct oz_hdr);
 		INIT_LIST_HEAD(&f->link);
@@ -359,13 +342,9 @@ static void oz_tx_isoc_free(struct oz_pd *pd, struct oz_tx_frame *f)
 {
 	pd->nb_queued_isoc_frames--;
 	list_del_init(&f->link);
-	if (pd->tx_pool_count < OZ_MAX_TX_POOL_SIZE) {
-		f->link.next = pd->tx_pool;
-		pd->tx_pool = &f->link;
-		pd->tx_pool_count++;
-	} else {
-		kfree(f);
-	}
+
+	kmem_cache_free(oz_tx_frame_cache, f);
+
 	oz_dbg(TX_FRAMES, "Releasing ISOC Frame isoc_nb= %d\n",
 	       pd->nb_queued_isoc_frames);
 }
@@ -375,15 +354,7 @@ static void oz_tx_isoc_free(struct oz_pd *pd, struct oz_tx_frame *f)
  */
 static void oz_tx_frame_free(struct oz_pd *pd, struct oz_tx_frame *f)
 {
-	spin_lock_bh(&pd->tx_frame_lock);
-	if (pd->tx_pool_count < OZ_MAX_TX_POOL_SIZE) {
-		f->link.next = pd->tx_pool;
-		pd->tx_pool = &f->link;
-		pd->tx_pool_count++;
-		f = NULL;
-	}
-	spin_unlock_bh(&pd->tx_frame_lock);
-	kfree(f);
+	kmem_cache_free(oz_tx_frame_cache, f);
 }
 
 /*
diff --git a/drivers/staging/ozwpan/ozpd.h b/drivers/staging/ozwpan/ozpd.h
index 43a26ea..212fab0 100644
--- a/drivers/staging/ozwpan/ozpd.h
+++ b/drivers/staging/ozwpan/ozpd.h
@@ -90,8 +90,6 @@ struct oz_pd {
 	unsigned	max_stream_buffering;
 	int		nb_queued_frames;
 	int		nb_queued_isoc_frames;
-	struct list_head *tx_pool;
-	int		tx_pool_count;
 	spinlock_t	tx_frame_lock;
 	struct list_head *last_sent_frame;
 	struct list_head tx_queue;
@@ -131,5 +129,6 @@ void oz_apps_init(void);
 void oz_apps_term(void);
 
 extern struct kmem_cache *oz_elt_info_cache;
+extern struct kmem_cache *oz_tx_frame_cache;
 
 #endif /* Sentry */
diff --git a/drivers/staging/ozwpan/ozproto.c b/drivers/staging/ozwpan/ozproto.c
index b592e96..db6ef99 100644
--- a/drivers/staging/ozwpan/ozproto.c
+++ b/drivers/staging/ozwpan/ozproto.c
@@ -53,6 +53,7 @@ static u16 g_apps = 0x1;
 static int g_processing_rx;
 
 struct kmem_cache *oz_elt_info_cache;
+struct kmem_cache *oz_tx_frame_cache;
 
 /*
  * Context: softirq-serialized
@@ -483,6 +484,7 @@ void oz_protocol_term(void)
 	spin_unlock_bh(&g_polling_lock);
 	oz_dbg(ON, "Protocol stopped\n");
 
+	kmem_cache_destroy(oz_tx_frame_cache);
 	kmem_cache_destroy(oz_elt_info_cache);
 }
 
@@ -771,6 +773,12 @@ int oz_protocol_init(char *devs)
 	if (!oz_elt_info_cache)
 		return -ENOMEM;
 
+	oz_tx_frame_cache = KMEM_CACHE(oz_tx_frame, 0);
+	if (!oz_tx_frame_cache) {
+		kmem_cache_destroy(oz_elt_info_cache);
+		return -ENOMEM;
+	}
+
 	skb_queue_head_init(&g_rx_queue);
 	if (devs[0] == '*') {
 		oz_binding_add(NULL);
diff --git a/drivers/staging/ozwpan/ozproto.h b/drivers/staging/ozwpan/ozproto.h
index b0f7459..73cc69b 100644
--- a/drivers/staging/ozwpan/ozproto.h
+++ b/drivers/staging/ozwpan/ozproto.h
@@ -66,5 +66,6 @@ int oz_get_pd_status_list(char *pd_list, int max_count);
 int oz_get_binding_list(char *buf, int max_if);
 
 extern struct kmem_cache *oz_elt_info_cache;
+extern struct kmem_cache *oz_tx_frame_cache;
 
 #endif /* _OZPROTO_H */
-- 
1.9.1

[PATCH 10/10] staging: ozwpan: Use list helpers

[Christoph Jaeger]

Make use of the various list helper functions to improve readability.

Signed-off-by: Christoph Jaeger <email@christophjaeger.info>
---
 drivers/staging/ozwpan/ozeltbuf.c |  60 +++++++--------------
 drivers/staging/ozwpan/ozhcd.c    |  96 +++++++++++-----------------------
 drivers/staging/ozwpan/ozpd.c     | 106 ++++++++++++--------------------------
 drivers/staging/ozwpan/ozproto.c  |  15 ++----
 4 files changed, 88 insertions(+), 189 deletions(-)

diff --git a/drivers/staging/ozwpan/ozeltbuf.c b/drivers/staging/ozwpan/ozeltbuf.c
index 81580cb..64d9fab 100644
--- a/drivers/staging/ozwpan/ozeltbuf.c
+++ b/drivers/staging/ozwpan/ozeltbuf.c
@@ -27,24 +27,12 @@ void oz_elt_buf_init(struct oz_elt_buf *buf)
  */
 void oz_elt_buf_term(struct oz_elt_buf *buf)
 {
-	struct list_head *e;
-	int i;
+	struct oz_elt_info *ei, *n;
 
-	/* Free any elements in the order or isoc lists. */
-	for (i = 0; i < 2; i++) {
-		struct list_head *list;
-		if (i)
-			list = &buf->order_list;
-		else
-			list = &buf->isoc_list;
-		e = list->next;
-		while (e != list) {
-			struct oz_elt_info *ei =
-				container_of(e, struct oz_elt_info, link_order);
-			e = e->next;
-			kfree(ei);
-		}
-	}
+	list_for_each_entry_safe(ei, n, &buf->isoc_list, link_order)
+		kfree(ei);
+	list_for_each_entry_safe(ei, n, &buf->order_list, link_order)
+		kfree(ei);
 }
 
 /*
@@ -77,16 +65,11 @@ void oz_elt_info_free(struct oz_elt_buf *buf, struct oz_elt_info *ei)
  */
 void oz_elt_info_free_chain(struct oz_elt_buf *buf, struct list_head *list)
 {
-	struct list_head *e;
+	struct oz_elt_info *ei, *n;
 
-	e = list->next;
 	spin_lock_bh(&buf->lock);
-	while (e != list) {
-		struct oz_elt_info *ei;
-		ei = container_of(e, struct oz_elt_info, link);
-		e = e->next;
+	list_for_each_entry_safe(ei, n, list->next, link)
 		oz_elt_info_free(buf, ei);
-	}
 	spin_unlock_bh(&buf->lock);
 }
 
@@ -111,14 +94,13 @@ int oz_elt_stream_create(struct oz_elt_buf *buf, u8 id, int max_buf_count)
 
 int oz_elt_stream_delete(struct oz_elt_buf *buf, u8 id)
 {
-	struct list_head *e;
+	struct list_head *e, *n;
 	struct oz_elt_stream *st = NULL;
 
 	oz_dbg(ON, "%s: (0x%x)\n", __func__, id);
 	spin_lock_bh(&buf->lock);
-	e = buf->stream_list.next;
-	while (e != &buf->stream_list) {
-		st = container_of(e, struct oz_elt_stream, link);
+	list_for_each(e, &buf->stream_list) {
+		st = list_entry(e, struct oz_elt_stream, link);
 		if (st->id == id) {
 			list_del(e);
 			break;
@@ -129,11 +111,9 @@ int oz_elt_stream_delete(struct oz_elt_buf *buf, u8 id)
 		spin_unlock_bh(&buf->lock);
 		return -1;
 	}
-	e = st->elt_list.next;
-	while (e != &st->elt_list) {
+	list_for_each_safe(e, n, &st->elt_list) {
 		struct oz_elt_info *ei =
-			container_of(e, struct oz_elt_info, link);
-		e = e->next;
+			list_entry(e, struct oz_elt_info, link);
 		list_del_init(&ei->link);
 		list_del_init(&ei->link_order);
 		st->buf_count -= ei->length;
@@ -173,7 +153,7 @@ int oz_queue_elt_info(struct oz_elt_buf *buf, u8 isoc, u8 id,
 
 	if (id) {
 		list_for_each(e, &buf->stream_list) {
-			st = container_of(e, struct oz_elt_stream, link);
+			st = list_entry(e, struct oz_elt_stream, link);
 			if (st->id == id)
 				break;
 		}
@@ -228,22 +208,18 @@ int oz_select_elts_for_tx(struct oz_elt_buf *buf, u8 isoc, unsigned *len,
 		unsigned max_len, struct list_head *list)
 {
 	int count = 0;
-	struct list_head *e;
 	struct list_head *el;
-	struct oz_elt_info *ei;
+	struct oz_elt_info *ei, *n;
 
 	spin_lock_bh(&buf->lock);
 	if (isoc)
 		el = &buf->isoc_list;
 	else
 		el = &buf->order_list;
-	e = el->next;
-	while (e != el) {
-		struct oz_app_hdr *app_hdr;
-		ei = container_of(e, struct oz_elt_info, link_order);
-		e = e->next;
+
+	list_for_each_entry_safe(ei, n, el, link_order) {
 		if ((*len + ei->length) <= max_len) {
-			app_hdr = (struct oz_app_hdr *)
+			struct oz_app_hdr *app_hdr = (struct oz_app_hdr *)
 				&ei->data[sizeof(struct oz_elt)];
 			app_hdr->elt_seq_num = buf->tx_seq_num[ei->app_id]++;
 			if (buf->tx_seq_num[ei->app_id] == 0)
@@ -271,5 +247,5 @@ int oz_select_elts_for_tx(struct oz_elt_buf *buf, u8 isoc, unsigned *len,
 
 int oz_are_elts_available(struct oz_elt_buf *buf)
 {
-	return buf->order_list.next != &buf->order_list;
+	return !list_empty(&buf->order_list);
 }
diff --git a/drivers/staging/ozwpan/ozhcd.c b/drivers/staging/ozwpan/ozhcd.c
index 3b603c5..0f7fa69 100644
--- a/drivers/staging/ozwpan/ozhcd.c
+++ b/drivers/staging/ozwpan/ozhcd.c
@@ -45,10 +45,6 @@
  */
 #define OZ_PLAT_DEV_NAME	"ozwpan"
 
-/* Get endpoint object from the containing link.
- */
-#define ep_from_link(__e) container_of((__e), struct oz_endpoint, link)
-
 /*EP0 timeout before ep0 request is again added to TX queue. (13*8 = 98mSec)
  */
 #define EP0_TIMEOUT_COUNTER 13
@@ -308,12 +304,10 @@ static struct oz_urb_link *oz_uncancel_urb(struct oz_hcd *ozhcd,
 		struct urb *urb)
 {
 	struct oz_urb_link *urbl;
-	struct list_head *e;
 
-	list_for_each(e, &ozhcd->urb_cancel_list) {
-		urbl = container_of(e, struct oz_urb_link, link);
+	list_for_each_entry(urbl, &ozhcd->urb_cancel_list, link) {
 		if (urb == urbl->urb) {
-			list_del_init(e);
+			list_del_init(&urbl->link);
 			return urbl;
 		}
 	}
@@ -372,10 +366,9 @@ static void oz_complete_urb(struct usb_hcd *hcd, struct urb *urb,
 static void oz_ep_free(struct oz_port *port, struct oz_endpoint *ep)
 {
 	if (port) {
-		struct list_head list;
+		LIST_HEAD(list);
 		struct oz_hcd *ozhcd = port->ozhcd;
 
-		INIT_LIST_HEAD(&list);
 		if (ep->flags & OZ_F_EP_HAVE_STREAM)
 			oz_usb_stream_delete(port->hpd, ep->ep_num);
 		/* Transfer URBs to the orphanage while we hold the lock. */
@@ -521,7 +514,7 @@ static int oz_dequeue_ep_urb(struct oz_port *port, u8 ep_addr, int in_dir,
 		struct list_head *e;
 
 		list_for_each(e, &ep->urb_list) {
-			urbl = container_of(e, struct oz_urb_link, link);
+			urbl = list_entry(e, struct oz_urb_link, link);
 			if (urbl->urb == urb) {
 				list_del_init(e);
 				break;
@@ -553,7 +546,7 @@ static struct urb *oz_find_urb_by_id(struct oz_port *port, int ep_ix,
 		struct list_head *e;
 
 		list_for_each(e, &ep->urb_list) {
-			urbl = container_of(e, struct oz_urb_link, link);
+			urbl = list_entry(e, struct oz_urb_link, link);
 			if (urbl->req_id == req_id) {
 				urb = urbl->urb;
 				list_del_init(e);
@@ -1046,21 +1039,17 @@ int oz_hcd_heartbeat(void *hport)
 	int rc = 0;
 	struct oz_port *port = (struct oz_port *)hport;
 	struct oz_hcd *ozhcd = port->ozhcd;
-	struct oz_urb_link *urbl;
-	struct list_head xfr_list;
-	struct list_head *e;
-	struct list_head *n;
+	struct oz_urb_link *urbl, *n;
+	LIST_HEAD(xfr_list);
 	struct urb *urb;
 	struct oz_endpoint *ep;
 	struct timespec ts, delta;
 
 	getrawmonotonic(&ts);
-	INIT_LIST_HEAD(&xfr_list);
 	/* Check the OUT isoc endpoints to see if any URB data can be sent.
 	 */
 	spin_lock_bh(&ozhcd->hcd_lock);
-	list_for_each(e, &port->isoc_out_ep) {
-		ep = ep_from_link(e);
+	list_for_each_entry(ep, &port->isoc_out_ep, link) {
 		if (ep->credit < 0)
 			continue;
 		delta = timespec_sub(ts, ep->timestamp);
@@ -1083,10 +1072,9 @@ int oz_hcd_heartbeat(void *hport)
 	spin_unlock_bh(&ozhcd->hcd_lock);
 	/* Send to PD and complete URBs.
 	 */
-	list_for_each_safe(e, n, &xfr_list) {
-		urbl = container_of(e, struct oz_urb_link, link);
+	list_for_each_entry_safe(urbl, n, &xfr_list, link) {
 		urb = urbl->urb;
-		list_del_init(e);
+		list_del_init(&urbl->link);
 		urb->error_count = 0;
 		urb->start_frame = oz_usb_get_frame_number();
 		oz_usb_send_isoc(port->hpd, urbl->ep_num, urb);
@@ -1096,9 +1084,7 @@ int oz_hcd_heartbeat(void *hport)
 	/* Check the IN isoc endpoints to see if any URBs can be completed.
 	 */
 	spin_lock_bh(&ozhcd->hcd_lock);
-	list_for_each(e, &port->isoc_in_ep) {
-		struct oz_endpoint *ep = ep_from_link(e);
-
+	list_for_each_entry(ep, &port->isoc_in_ep, link) {
 		if (ep->flags & OZ_F_EP_BUFFERING) {
 			if (ep->buffered_units >= OZ_IN_BUFFERING_UNITS) {
 				ep->flags &= ~OZ_F_EP_BUFFERING;
@@ -1111,10 +1097,7 @@ int oz_hcd_heartbeat(void *hport)
 		delta = timespec_sub(ts, ep->timestamp);
 		ep->credit += div_u64(timespec_to_ns(&delta), NSEC_PER_MSEC);
 		ep->timestamp = ts;
-		while (!list_empty(&ep->urb_list)) {
-			struct oz_urb_link *urbl =
-				list_first_entry(&ep->urb_list,
-					struct oz_urb_link, link);
+		list_for_each_entry_safe(urbl, n, &ep->urb_list, link) {
 			struct urb *urb = urbl->urb;
 			int len = 0;
 			int copy_len;
@@ -1161,10 +1144,9 @@ int oz_hcd_heartbeat(void *hport)
 	spin_unlock_bh(&ozhcd->hcd_lock);
 	/* Complete the filled URBs.
 	 */
-	list_for_each_safe(e, n, &xfr_list) {
-		urbl = container_of(e, struct oz_urb_link, link);
+	list_for_each_entry_safe(urbl, n, &xfr_list, link) {
 		urb = urbl->urb;
-		list_del_init(e);
+		list_del_init(&urbl->link);
 		oz_free_urb_link(urbl);
 		oz_complete_urb(port->ozhcd->hcd, urb, 0);
 	}
@@ -1173,15 +1155,11 @@ int oz_hcd_heartbeat(void *hport)
 	 */
 	ep = port->out_ep[0];
 	if (ep) {
-		struct list_head *e;
-		struct list_head *n;
-
 		spin_lock_bh(&ozhcd->hcd_lock);
-		list_for_each_safe(e, n, &ep->urb_list) {
-			urbl = container_of(e, struct oz_urb_link, link);
+		list_for_each_entry_safe(urbl, n, &ep->urb_list, link) {
 			if (urbl->submit_counter > EP0_TIMEOUT_COUNTER) {
 				oz_dbg(ON, "Request 0x%p timeout\n", urbl->urb);
-				list_move_tail(e, &xfr_list);
+				list_move_tail(&urbl->link, &xfr_list);
 				urbl->submit_counter = 0;
 			} else {
 				urbl->submit_counter++;
@@ -1190,10 +1168,7 @@ int oz_hcd_heartbeat(void *hport)
 		if (!list_empty(&ep->urb_list))
 			rc = 1;
 		spin_unlock_bh(&ozhcd->hcd_lock);
-		e = xfr_list.next;
-		while (e != &xfr_list) {
-			urbl = container_of(e, struct oz_urb_link, link);
-			e = e->next;
+		list_for_each_entry_safe(urbl, n, &xfr_list, link) {
 			oz_dbg(ON, "Resending request to PD\n");
 			oz_process_ep0_urb(ozhcd, urbl->urb, GFP_ATOMIC);
 			oz_free_urb_link(urbl);
@@ -1292,12 +1267,12 @@ static void oz_clean_endpoints_for_interface(struct usb_hcd *hcd,
 	struct oz_hcd *ozhcd = port->ozhcd;
 	unsigned mask;
 	int i;
-	struct list_head ep_list;
+	LIST_HEAD(ep_list);
+	struct oz_endpoint *ep, *n;
 
 	oz_dbg(ON, "Deleting endpoints for interface %d\n", if_ix);
 	if (if_ix >= port->num_iface)
 		return;
-	INIT_LIST_HEAD(&ep_list);
 	spin_lock_bh(&ozhcd->hcd_lock);
 	mask = port->iface[if_ix].ep_mask;
 	port->iface[if_ix].ep_mask = 0;
@@ -1321,9 +1296,7 @@ static void oz_clean_endpoints_for_interface(struct usb_hcd *hcd,
 		}
 	}
 	spin_unlock_bh(&ozhcd->hcd_lock);
-	while (!list_empty(&ep_list)) {
-		struct oz_endpoint *ep =
-			list_first_entry(&ep_list, struct oz_endpoint, link);
+	list_for_each_entry_safe(ep, n, &ep_list, link) {
 		list_del_init(&ep->link);
 		oz_ep_free(port, ep);
 	}
@@ -1594,6 +1567,7 @@ static void oz_urb_process_tasklet(unsigned long unused)
 	unsigned long irq_state;
 	struct urb *urb;
 	struct oz_hcd *ozhcd = oz_hcd_claim();
+	struct oz_urb_link *urbl, *n;
 	int rc = 0;
 
 	if (ozhcd == NULL)
@@ -1603,10 +1577,7 @@ static void oz_urb_process_tasklet(unsigned long unused)
 	 * appropriately while removing urbs.
 	 */
 	spin_lock_irqsave(&g_tasklet_lock, irq_state);
-	while (!list_empty(&ozhcd->urb_pending_list)) {
-		struct oz_urb_link *urbl =
-			list_first_entry(&ozhcd->urb_pending_list,
-				struct oz_urb_link, link);
+	list_for_each_entry_safe(urbl, n, &ozhcd->urb_pending_list, link) {
 		list_del_init(&urbl->link);
 		spin_unlock_irqrestore(&g_tasklet_lock, irq_state);
 		urb = urbl->urb;
@@ -1651,7 +1622,7 @@ static void oz_urb_cancel(struct oz_port *port, u8 ep_num, struct urb *urb)
 	 */
 	spin_lock_irqsave(&g_tasklet_lock, irq_state);
 	list_for_each(e, &ozhcd->urb_cancel_list) {
-		urbl = container_of(e, struct oz_urb_link, link);
+		urbl = list_entry(e, struct oz_urb_link, link);
 		if (urb == urbl->urb) {
 			list_del_init(e);
 			spin_unlock_irqrestore(&g_tasklet_lock, irq_state);
@@ -1665,7 +1636,7 @@ static void oz_urb_cancel(struct oz_port *port, u8 ep_num, struct urb *urb)
 	 */
 	spin_lock_irqsave(&ozhcd->hcd_lock, irq_state);
 	list_for_each(e, &ozhcd->orphanage) {
-		urbl = container_of(e, struct oz_urb_link, link);
+		urbl = list_entry(e, struct oz_urb_link, link);
 		if (urbl->urb == urb) {
 			list_del(e);
 			oz_dbg(ON, "Found urb in orphanage\n");
@@ -1695,15 +1666,13 @@ static void oz_urb_cancel_tasklet(unsigned long unused)
 {
 	unsigned long irq_state;
 	struct urb *urb;
+	struct oz_urb_link *urbl, *n;
 	struct oz_hcd *ozhcd = oz_hcd_claim();
 
 	if (ozhcd == NULL)
 		return;
 	spin_lock_irqsave(&g_tasklet_lock, irq_state);
-	while (!list_empty(&ozhcd->urb_cancel_list)) {
-		struct oz_urb_link *urbl =
-			list_first_entry(&ozhcd->urb_cancel_list,
-				struct oz_urb_link, link);
+	list_for_each_entry_safe(urbl, n, &ozhcd->urb_cancel_list, link) {
 		list_del_init(&urbl->link);
 		spin_unlock_irqrestore(&g_tasklet_lock, irq_state);
 		urb = urbl->urb;
@@ -1722,11 +1691,9 @@ static void oz_urb_cancel_tasklet(unsigned long unused)
 static void oz_hcd_clear_orphanage(struct oz_hcd *ozhcd, int status)
 {
 	if (ozhcd) {
-		struct oz_urb_link *urbl;
+		struct oz_urb_link *urbl, *n;
 
-		while (!list_empty(&ozhcd->orphanage)) {
-			urbl = list_first_entry(&ozhcd->orphanage,
-				struct oz_urb_link, link);
+		list_for_each_entry_safe(urbl, n, &ozhcd->orphanage, link) {
 			list_del(&urbl->link);
 			oz_complete_urb(ozhcd->hcd, urbl->urb, status);
 			oz_free_urb_link(urbl);
@@ -1824,14 +1791,13 @@ static struct oz_urb_link *oz_remove_urb(struct oz_endpoint *ep,
 				struct urb *urb)
 {
 	struct oz_urb_link *urbl;
-	struct list_head *e;
 
 	if (unlikely(ep == NULL))
 		return NULL;
-	list_for_each(e, &ep->urb_list) {
-		urbl = container_of(e, struct oz_urb_link, link);
+
+	list_for_each_entry(urbl, &ep->urb_list, link) {
 		if (urbl->urb == urb) {
-			list_del_init(e);
+			list_del_init(&urbl->link);
 			if (usb_pipeisoc(urb->pipe)) {
 				ep->credit -= urb->number_of_packets;
 				if (ep->credit < 0)
diff --git a/drivers/staging/ozwpan/ozpd.c b/drivers/staging/ozwpan/ozpd.c
index 8048ea3..0dc475e 100644
--- a/drivers/staging/ozwpan/ozpd.c
+++ b/drivers/staging/ozwpan/ozpd.c
@@ -137,10 +137,7 @@ struct oz_pd *oz_pd_alloc(const u8 *mac_addr)
  */
 static void oz_pd_free(struct work_struct *work)
 {
-	struct list_head *e;
-	struct oz_tx_frame *f;
-	struct oz_isoc_stream *st;
-	struct oz_farewell *fwell;
+	struct list_head *e, *n;
 	struct oz_pd *pd;
 
 	oz_pd_dbg(pd, ON, "Destroying PD\n");
@@ -148,33 +145,24 @@ static void oz_pd_free(struct work_struct *work)
 	/*Disable timer tasklets*/
 	tasklet_kill(&pd->heartbeat_tasklet);
 	tasklet_kill(&pd->timeout_tasklet);
-	/* Delete any streams.
-	 */
-	e = pd->stream_list.next;
-	while (e != &pd->stream_list) {
-		st = container_of(e, struct oz_isoc_stream, link);
-		e = e->next;
-		oz_isoc_stream_free(st);
-	}
-	/* Free any queued tx frames.
-	 */
-	e = pd->tx_queue.next;
-	while (e != &pd->tx_queue) {
-		f = container_of(e, struct oz_tx_frame, link);
-		e = e->next;
+
+	/* Free streams, queued tx frames and farewells. */
+
+	list_for_each_safe(e, n, &pd->stream_list)
+		oz_isoc_stream_free(list_entry(e, struct oz_isoc_stream, link));
+
+	list_for_each_safe(e, n, &pd->tx_queue) {
+		struct oz_tx_frame *f = list_entry(e, struct oz_tx_frame, link);
 		if (f->skb != NULL)
 			kfree_skb(f->skb);
 		oz_retire_frame(pd, f);
 	}
+
 	oz_elt_buf_term(&pd->elt_buff);
-	/* Free any farewells.
-	 */
-	e = pd->farewell_list.next;
-	while (e != &pd->farewell_list) {
-		fwell = container_of(e, struct oz_farewell, link);
-		e = e->next;
-		kfree(fwell);
-	}
+
+	list_for_each_safe(e, n, &pd->farewell_list)
+		kfree(list_entry(e, struct oz_farewell, link));
+
 	if (pd->net_dev)
 		dev_put(pd->net_dev);
 	kfree(pd);
@@ -418,7 +406,7 @@ static struct sk_buff *oz_build_frame(struct oz_pd *pd, struct oz_tx_frame *f)
 	struct net_device *dev = pd->net_dev;
 	struct oz_hdr *oz_hdr;
 	struct oz_elt *elt;
-	struct list_head *e;
+	struct oz_elt_info *ei;
 
 	/* Allocate skb with enough space for the lower layers as well
 	 * as the space we need.
@@ -443,9 +431,7 @@ static struct sk_buff *oz_build_frame(struct oz_pd *pd, struct oz_tx_frame *f)
 	/* Copy the elements into the frame body.
 	 */
 	elt = (struct oz_elt *)(oz_hdr+1);
-	for (e = f->elt_list.next; e != &f->elt_list; e = e->next) {
-		struct oz_elt_info *ei;
-		ei = container_of(e, struct oz_elt_info, link);
+	list_for_each_entry(ei, &f->elt_list, link) {
 		memcpy(elt, ei->data, ei->length);
 		elt = oz_next_elt(elt);
 	}
@@ -460,13 +446,9 @@ fail:
  */
 static void oz_retire_frame(struct oz_pd *pd, struct oz_tx_frame *f)
 {
-	struct list_head *e;
-	struct oz_elt_info *ei;
+	struct oz_elt_info *ei, *n;
 
-	e = f->elt_list.next;
-	while (e != &f->elt_list) {
-		ei = container_of(e, struct oz_elt_info, link);
-		e = e->next;
+	list_for_each_entry_safe(ei, n, &f->elt_list, link) {
 		list_del_init(&ei->link);
 		if (ei->callback)
 			ei->callback(pd, ei->context);
@@ -492,7 +474,7 @@ static int oz_send_next_queued_frame(struct oz_pd *pd, int more_data)
 		spin_unlock(&pd->tx_frame_lock);
 		return -1;
 	}
-	f = container_of(e, struct oz_tx_frame, link);
+	f = list_entry(e, struct oz_tx_frame, link);
 
 	if (f->skb != NULL) {
 		skb = f->skb;
@@ -580,15 +562,13 @@ static int oz_send_isoc_frame(struct oz_pd *pd)
 	struct net_device *dev = pd->net_dev;
 	struct oz_hdr *oz_hdr;
 	struct oz_elt *elt;
-	struct list_head *e;
-	struct list_head list;
+	struct oz_elt_info *ei;
+	LIST_HEAD(list);
 	int total_size = sizeof(struct oz_hdr);
 
-	INIT_LIST_HEAD(&list);
-
 	oz_select_elts_for_tx(&pd->elt_buff, 1, &total_size,
 		pd->max_tx_size, &list);
-	if (list.next == &list)
+	if (list_empty(&list))
 		return 0;
 	skb = alloc_skb(total_size + OZ_ALLOCATED_SPACE(dev), GFP_ATOMIC);
 	if (skb == NULL) {
@@ -610,9 +590,7 @@ static int oz_send_isoc_frame(struct oz_pd *pd)
 	oz_hdr->last_pkt_num = pd->trigger_pkt_num & OZ_LAST_PN_MASK;
 	elt = (struct oz_elt *)(oz_hdr+1);
 
-	for (e = list.next; e != &list; e = e->next) {
-		struct oz_elt_info *ei;
-		ei = container_of(e, struct oz_elt_info, link);
+	list_for_each_entry(ei, &list, link) {
 		memcpy(elt, ei->data, ei->length);
 		elt = oz_next_elt(elt);
 	}
@@ -626,41 +604,30 @@ static int oz_send_isoc_frame(struct oz_pd *pd)
  */
 void oz_retire_tx_frames(struct oz_pd *pd, u8 lpn)
 {
-	struct list_head *e;
-	struct oz_tx_frame *f;
-	struct list_head *first = NULL;
-	struct list_head *last = NULL;
+	struct oz_tx_frame *f, *tmp = NULL;
 	u8 diff;
 	u32 pkt_num;
 
+	LIST_HEAD(list);
+
 	spin_lock(&pd->tx_frame_lock);
-	e = pd->tx_queue.next;
-	while (e != &pd->tx_queue) {
-		f = container_of(e, struct oz_tx_frame, link);
+	list_for_each_entry(f, &pd->tx_queue, link) {
 		pkt_num = le32_to_cpu(get_unaligned(&f->hdr.pkt_num));
 		diff = (lpn - (pkt_num & OZ_LAST_PN_MASK)) & OZ_LAST_PN_MASK;
 		if ((diff > OZ_LAST_PN_HALF_CYCLE) || (pkt_num == 0))
 			break;
 		oz_dbg(TX_FRAMES, "Releasing pkt_num= %u, nb= %d\n",
 		       pkt_num, pd->nb_queued_frames);
-		if (first == NULL)
-			first = e;
-		last = e;
-		e = e->next;
+		tmp = f;
 		pd->nb_queued_frames--;
 	}
-	if (first) {
-		last->next->prev = &pd->tx_queue;
-		pd->tx_queue.next = last->next;
-		last->next = NULL;
-	}
+	if (tmp)
+		list_cut_position(&list, &pd->tx_queue, &tmp->link);
 	pd->last_sent_frame = &pd->tx_queue;
 	spin_unlock(&pd->tx_frame_lock);
-	while (first) {
-		f = container_of(first, struct oz_tx_frame, link);
-		first = first->next;
+
+	list_for_each_entry_safe(f, tmp, &list, link)
 		oz_retire_frame(pd, f);
-	}
 }
 
 /*
@@ -669,11 +636,9 @@ void oz_retire_tx_frames(struct oz_pd *pd, u8 lpn)
  */
 static struct oz_isoc_stream *pd_stream_find(struct oz_pd *pd, u8 ep_num)
 {
-	struct list_head *e;
 	struct oz_isoc_stream *st;
 
-	list_for_each(e, &pd->stream_list) {
-		st = container_of(e, struct oz_isoc_stream, link);
+	list_for_each_entry(st, &pd->stream_list, link) {
 		if (st->ep_num == ep_num)
 			return st;
 	}
@@ -810,14 +775,11 @@ int oz_send_isoc_unit(struct oz_pd *pd, u8 ep_num, const u8 *data, int len)
 			struct oz_tx_frame *isoc_unit = NULL;
 			int nb = pd->nb_queued_isoc_frames;
 			if (nb >= pd->isoc_latency) {
-				struct list_head *e;
 				struct oz_tx_frame *f;
 				oz_dbg(TX_FRAMES, "Dropping ISOC Unit nb= %d\n",
 				       nb);
 				spin_lock(&pd->tx_frame_lock);
-				list_for_each(e, &pd->tx_queue) {
-					f = container_of(e, struct oz_tx_frame,
-									link);
+				list_for_each_entry(f, &pd->tx_queue, link) {
 					if (f->skb != NULL) {
 						oz_tx_isoc_free(pd, f);
 						break;
diff --git a/drivers/staging/ozwpan/ozproto.c b/drivers/staging/ozwpan/ozproto.c
index c1fb442..fc010ae 100644
--- a/drivers/staging/ozwpan/ozproto.c
+++ b/drivers/staging/ozwpan/ozproto.c
@@ -185,7 +185,7 @@ static struct oz_pd *oz_connect_req(struct oz_pd *cur_pd, struct oz_elt *elt,
 		getnstimeofday(&pd->last_rx_timestamp);
 		spin_lock_bh(&g_polling_lock);
 		list_for_each(e, &g_pd_list) {
-			pd2 = container_of(e, struct oz_pd, link);
+			pd2 = list_entry(e, struct oz_pd, link);
 			if (ether_addr_equal(pd2->mac_addr, pd_addr)) {
 				free_pd = pd;
 				pd = pd2;
@@ -601,13 +601,11 @@ void oz_pd_request_heartbeat(struct oz_pd *pd)
 struct oz_pd *oz_pd_find(const u8 *mac_addr)
 {
 	struct oz_pd *pd;
-	struct list_head *e;
 
 	spin_lock_bh(&g_polling_lock);
-	list_for_each(e, &g_pd_list) {
-		pd = container_of(e, struct oz_pd, link);
+	list_for_each_entry(pd, &g_pd_list, link) {
 		if (ether_addr_equal(pd->mac_addr, mac_addr)) {
-			atomic_inc(&pd->ref_count);
+			oz_pd_get(pd);
 			spin_unlock_bh(&g_polling_lock);
 			return pd;
 		}
@@ -700,11 +698,10 @@ void oz_binding_add(const char *net_dev)
  */
 static void pd_stop_all_for_device(struct net_device *net_dev)
 {
-	struct list_head h;
+	LIST_HEAD(h);
 	struct oz_pd *pd;
 	struct oz_pd *n;
 
-	INIT_LIST_HEAD(&h);
 	spin_lock_bh(&g_polling_lock);
 	list_for_each_entry_safe(pd, n, &g_pd_list, link) {
 		if (pd->net_dev == net_dev) {
@@ -799,14 +796,12 @@ int oz_protocol_init(char *devs)
 int oz_get_pd_list(struct oz_mac_addr *addr, int max_count)
 {
 	struct oz_pd *pd;
-	struct list_head *e;
 	int count = 0;
 
 	spin_lock_bh(&g_polling_lock);
-	list_for_each(e, &g_pd_list) {
+	list_for_each_entry(pd, &g_pd_list, link) {
 		if (count >= max_count)
 			break;
-		pd = container_of(e, struct oz_pd, link);
 		ether_addr_copy((u8 *)&addr[count++], pd->mac_addr);
 	}
 	spin_unlock_bh(&g_polling_lock);
-- 
1.9.1