[PATCH -next v1] wireless: ath9k-htc: only load firmware in need

[PATCH -next v1] wireless: ath9k-htc: only load firmware in need

[Ming Lei]

It is not necessary to hold the firmware memory during the whole
driver lifetime, and obviously it does waste memory. Suppose there
are 4 ath9k-htc usb dongles working, kernel has to consume about
4*50KBytes RAM to cache firmware for all dongles. After applying the
patch, kernel only caches one single firmware image in RAM for
all ath9k-htc devices just during system suspend/resume cycle.

When system is ready for loading firmware, ath9k-htc can request
the loading from usersapce. During system resume, ath9k-htc still
can load the firmware which was cached in kernel memory before
system suspend.

Cc: ath9k-devel@lists.ath9k.org
Cc: "Luis R. Rodriguez" <mcgrof@qca.qualcomm.com>
Cc: Jouni Malinen <jouni@qca.qualcomm.com>
Cc: Vasanthakumar Thiagarajan <vthiagar@qca.qualcomm.com>
Cc: Senthil Balasubramanian <senthilb@qca.qualcomm.com>
Cc: "John W. Linville" <linville@tuxdriver.com>
Signed-off-by: Ming Lei <ming.lei@canonical.com>
---
v1:
	fix double free of firmware in failue path of
	ath9k_hif_usb_firmware_cb

This patch(just behaviour instead of build) depends on firmware
cache patch set which has entered -next tree already via driver core
tree.
---
 drivers/net/wireless/ath/ath9k/hif_usb.c |   33 ++++++++++++++++++++----------
 drivers/net/wireless/ath/ath9k/hif_usb.h |    4 +++-
 2 files changed, 25 insertions(+), 12 deletions(-)

diff --git a/drivers/net/wireless/ath/ath9k/hif_usb.c b/drivers/net/wireless/ath/ath9k/hif_usb.c
index aa327ad..ee6e50a 100644
--- a/drivers/net/wireless/ath/ath9k/hif_usb.c
+++ b/drivers/net/wireless/ath/ath9k/hif_usb.c
@@ -973,8 +973,8 @@ static void ath9k_hif_usb_dealloc_urbs(struct hif_device_usb *hif_dev)
 static int ath9k_hif_usb_download_fw(struct hif_device_usb *hif_dev)
 {
 	int transfer, err;
-	const void *data = hif_dev->firmware->data;
-	size_t len = hif_dev->firmware->size;
+	const void *data = hif_dev->fw_data;
+	size_t len = hif_dev->fw_size;
 	u32 addr = AR9271_FIRMWARE;
 	u8 *buf = kzalloc(4096, GFP_KERNEL);
 	u32 firm_offset;
@@ -1017,7 +1017,7 @@ static int ath9k_hif_usb_download_fw(struct hif_device_usb *hif_dev)
 		return -EIO;
 
 	dev_info(&hif_dev->udev->dev, "ath9k_htc: Transferred FW: %s, size: %ld\n",
-		 hif_dev->fw_name, (unsigned long) hif_dev->firmware->size);
+		 hif_dev->fw_name, (unsigned long) hif_dev->fw_size);
 
 	return 0;
 }
@@ -1099,11 +1099,11 @@ static void ath9k_hif_usb_firmware_cb(const struct firmware *fw, void *context)
 
 	hif_dev->htc_handle = ath9k_htc_hw_alloc(hif_dev, &hif_usb,
 						 &hif_dev->udev->dev);
-	if (hif_dev->htc_handle == NULL) {
-		goto err_fw;
-	}
+	if (hif_dev->htc_handle == NULL)
+		goto err_dev_alloc;
 
-	hif_dev->firmware = fw;
+	hif_dev->fw_data = fw->data;
+	hif_dev->fw_size = fw->size;
 
 	/* Proceed with initialization */
 
@@ -1121,6 +1121,8 @@ static void ath9k_hif_usb_firmware_cb(const struct firmware *fw, void *context)
 		goto err_htc_hw_init;
 	}
 
+	release_firmware(fw);
+	hif_dev->flags |= HIF_USB_READY;
 	complete(&hif_dev->fw_done);
 
 	return;
@@ -1129,8 +1131,8 @@ err_htc_hw_init:
 	ath9k_hif_usb_dev_deinit(hif_dev);
 err_dev_init:
 	ath9k_htc_hw_free(hif_dev->htc_handle);
+err_dev_alloc:
 	release_firmware(fw);
-	hif_dev->firmware = NULL;
 err_fw:
 	ath9k_hif_usb_firmware_fail(hif_dev);
 }
@@ -1277,11 +1279,10 @@ static void ath9k_hif_usb_disconnect(struct usb_interface *interface)
 
 	wait_for_completion(&hif_dev->fw_done);
 
-	if (hif_dev->firmware) {
+	if (hif_dev->flags & HIF_USB_READY) {
 		ath9k_htc_hw_deinit(hif_dev->htc_handle, unplugged);
 		ath9k_htc_hw_free(hif_dev->htc_handle);
 		ath9k_hif_usb_dev_deinit(hif_dev);
-		release_firmware(hif_dev->firmware);
 	}
 
 	usb_set_intfdata(interface, NULL);
@@ -1317,13 +1318,23 @@ static int ath9k_hif_usb_resume(struct usb_interface *interface)
 	struct hif_device_usb *hif_dev = usb_get_intfdata(interface);
 	struct htc_target *htc_handle = hif_dev->htc_handle;
 	int ret;
+	const struct firmware *fw;
 
 	ret = ath9k_hif_usb_alloc_urbs(hif_dev);
 	if (ret)
 		return ret;
 
-	if (hif_dev->firmware) {
+	if (hif_dev->flags & HIF_USB_READY) {
+		/* request cached firmware during suspend/resume cycle */
+		ret = request_firmware(&fw, hif_dev->fw_name,
+				       &hif_dev->udev->dev);
+		if (ret)
+			goto fail_resume;
+
+		hif_dev->fw_data = fw->data;
+		hif_dev->fw_size = fw->size;
 		ret = ath9k_hif_usb_download_fw(hif_dev);
+		release_firmware(fw);
 		if (ret)
 			goto fail_resume;
 	} else {
diff --git a/drivers/net/wireless/ath/ath9k/hif_usb.h b/drivers/net/wireless/ath/ath9k/hif_usb.h
index 487ff65..51496e7 100644
--- a/drivers/net/wireless/ath/ath9k/hif_usb.h
+++ b/drivers/net/wireless/ath/ath9k/hif_usb.h
@@ -85,12 +85,14 @@ struct cmd_buf {
 };
 
 #define HIF_USB_START BIT(0)
+#define HIF_USB_READY BIT(1)
 
 struct hif_device_usb {
 	struct usb_device *udev;
 	struct usb_interface *interface;
 	const struct usb_device_id *usb_device_id;
-	const struct firmware *firmware;
+	const void *fw_data;
+	size_t fw_size;
 	struct completion fw_done;
 	struct htc_target *htc_handle;
 	struct hif_usb_tx tx;
-- 
1.7.9.5

Re: [PATCH -next v1] wireless: ath9k-htc: only load firmware in need

[Ming Lei]

On Tue, Aug 21, 2012 at 4:04 PM, Ming Lei <ming.lei-Z7WLFzj8eWMS+FvcfC7Uqw@public.gmane.org> wrote:
> It is not necessary to hold the firmware memory during the whole
> driver lifetime, and obviously it does waste memory. Suppose there
> are 4 ath9k-htc usb dongles working, kernel has to consume about
> 4*50KBytes RAM to cache firmware for all dongles. After applying the
> patch, kernel only caches one single firmware image in RAM for
> all ath9k-htc devices just during system suspend/resume cycle.
>
> When system is ready for loading firmware, ath9k-htc can request
> the loading from usersapce. During system resume, ath9k-htc still
> can load the firmware which was cached in kernel memory before
> system suspend.
>
> Cc: ath9k-devel-xDcbHBWguxHbcTqmT+pZeQ@public.gmane.org
> Cc: "Luis R. Rodriguez" <mcgrof-A+ZNKFmMK5xy9aJCnZT0Uw@public.gmane.org>
> Cc: Jouni Malinen <jouni-A+ZNKFmMK5xy9aJCnZT0Uw@public.gmane.org>
> Cc: Vasanthakumar Thiagarajan <vthiagar-A+ZNKFmMK5xy9aJCnZT0Uw@public.gmane.org>
> Cc: Senthil Balasubramanian <senthilb-A+ZNKFmMK5xy9aJCnZT0Uw@public.gmane.org>
> Cc: "John W. Linville" <linville-2XuSBdqkA4R54TAoqtyWWQ@public.gmane.org>
> Signed-off-by: Ming Lei <ming.lei-Z7WLFzj8eWMS+FvcfC7Uqw@public.gmane.org>
> ---
> v1:
>         fix double free of firmware in failue path of
>         ath9k_hif_usb_firmware_cb

Gentle ping, :-)


Thanks,
--
Ming Lei
--
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Re: [PATCH -next v1] wireless: ath9k-htc: only load firmware in need

[Mohammed Shafi]

Hi,

On Sat, Sep 1, 2012 at 10:41 AM, Ming Lei <ming.lei@canonical.com> wrote:
> On Tue, Aug 21, 2012 at 4:04 PM, Ming Lei <ming.lei@canonical.com> wrote:
>> It is not necessary to hold the firmware memory during the whole
>> driver lifetime, and obviously it does waste memory. Suppose there
>> are 4 ath9k-htc usb dongles working, kernel has to consume about
>> 4*50KBytes RAM to cache firmware for all dongles. After applying the
>> patch, kernel only caches one single firmware image in RAM for
>> all ath9k-htc devices just during system suspend/resume cycle.
>>
>> When system is ready for loading firmware, ath9k-htc can request
>> the loading from usersapce. During system resume, ath9k-htc still
>> can load the firmware which was cached in kernel memory before
>> system suspend.
>>
>> Cc: ath9k-devel@lists.ath9k.org
>> Cc: "Luis R. Rodriguez" <mcgrof@qca.qualcomm.com>
>> Cc: Jouni Malinen <jouni@qca.qualcomm.com>
>> Cc: Vasanthakumar Thiagarajan <vthiagar@qca.qualcomm.com>
>> Cc: Senthil Balasubramanian <senthilb@qca.qualcomm.com>
>> Cc: "John W. Linville" <linville@tuxdriver.com>
>> Signed-off-by: Ming Lei <ming.lei@canonical.com>
>> ---
>> v1:
>>         fix double free of firmware in failue path of
>>         ath9k_hif_usb_firmware_cb
>
> Gentle ping, :-)

this patch is now in wireless-testing :-)

>
>
> Thanks,
> --
> Ming Lei
> --
> To unsubscribe from this list: send the line "unsubscribe linux-wireless" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html



-- 
thanks,
shafi