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* [PATCH v2] [media] Use common error handling code in 20 functions
@ 2018-02-19 18:11 SF Markus Elfring
  2018-02-19 18:37 ` Laurent Pinchart
                   ` (2 more replies)
  0 siblings, 3 replies; 10+ messages in thread
From: SF Markus Elfring @ 2018-02-19 18:11 UTC (permalink / raw)
  To: linux-media, Al Viro, Andi Shyti, Andrew Morton, Andrey Utkin,
	Arvind Yadav, Bhumika Goyal, Bjorn Helgaas, Brian Johnson,
	Christoph Böhmwalder, Christophe Jaillet, Colin Ian King,
	Daniele Nicolodi, David Härdeman, Devendra Sharma,
	Gustavo A. R. Silva, Hans Verkuil, Inki Dae, Joe Perches,
	Kees Cook, Laurent Pinchart, Masahiro Yamada,
	Mauro Carvalho Chehab, Max Kellermann, Mike Isely,
	Philippe Ombredanne, Sakari Ailus, Santosh Kumar Singh,
	Satendra Singh Thakur, Sean Young, Seung-Woo Kim, Shyam Saini,
	Thomas Gleixner, Todor Tomov, Wei Yongjun
  Cc: LKML, kernel-janitors

From: Markus Elfring <elfring@users.sourceforge.net>
Date: Mon, 19 Feb 2018 18:50:40 +0100

Adjust jump targets so that a bit of exception handling can be better
reused at the end of these functions.

This issue was partly detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
---

v2:
Hans Verkuil insisted on patch squashing. Thus several changes
were recombined based on source files from Linux next-20180216.

The implementation of the function "tda8261_set_params" was improved
after a notification by Christoph Böhmwalder on 2017-09-26.

 drivers/media/dvb-core/dmxdev.c                    | 16 ++++----
 drivers/media/dvb-frontends/tda1004x.c             | 20 ++++++----
 drivers/media/dvb-frontends/tda8261.c              | 19 ++++++----
 drivers/media/pci/bt8xx/dst.c                      | 19 ++++++----
 drivers/media/pci/bt8xx/dst_ca.c                   | 30 +++++++--------
 drivers/media/pci/cx88/cx88-input.c                | 17 +++++----
 drivers/media/platform/omap3isp/ispvideo.c         | 29 +++++++--------
 .../media/platform/qcom/camss-8x16/camss-csid.c    | 20 +++++-----
 drivers/media/tuners/tuner-xc2028.c                | 30 +++++++--------
 drivers/media/usb/cpia2/cpia2_usb.c                | 13 ++++---
 drivers/media/usb/gspca/gspca.c                    | 17 +++++----
 drivers/media/usb/gspca/sn9c20x.c                  | 17 +++++----
 drivers/media/usb/pvrusb2/pvrusb2-ioread.c         | 10 +++--
 drivers/media/usb/tm6000/tm6000-cards.c            |  7 ++--
 drivers/media/usb/tm6000/tm6000-dvb.c              | 11 ++++--
 drivers/media/usb/tm6000/tm6000-video.c            | 13 ++++---
 drivers/media/usb/ttusb-budget/dvb-ttusb-budget.c  | 13 +++----
 drivers/media/usb/ttusb-dec/ttusb_dec.c            | 43 ++++++++--------------
 drivers/media/usb/uvc/uvc_v4l2.c                   | 13 ++++---
 19 files changed, 180 insertions(+), 177 deletions(-)

diff --git a/drivers/media/dvb-core/dmxdev.c b/drivers/media/dvb-core/dmxdev.c
index 6d53af00190e..6a0411c91195 100644
--- a/drivers/media/dvb-core/dmxdev.c
+++ b/drivers/media/dvb-core/dmxdev.c
@@ -645,18 +645,18 @@ static int dvb_dmxdev_start_feed(struct dmxdev *dmxdev,
 	tsfeed->priv = filter;
 
 	ret = tsfeed->set(tsfeed, feed->pid, ts_type, ts_pes, timeout);
-	if (ret < 0) {
-		dmxdev->demux->release_ts_feed(dmxdev->demux, tsfeed);
-		return ret;
-	}
+	if (ret < 0)
+		goto release_feed;
 
 	ret = tsfeed->start_filtering(tsfeed);
-	if (ret < 0) {
-		dmxdev->demux->release_ts_feed(dmxdev->demux, tsfeed);
-		return ret;
-	}
+	if (ret < 0)
+		goto release_feed;
 
 	return 0;
+
+release_feed:
+	dmxdev->demux->release_ts_feed(dmxdev->demux, tsfeed);
+	return ret;
 }
 
 static int dvb_dmxdev_filter_start(struct dmxdev_filter *filter)
diff --git a/drivers/media/dvb-frontends/tda1004x.c b/drivers/media/dvb-frontends/tda1004x.c
index 58e3beff5adc..85ca111fc8c4 100644
--- a/drivers/media/dvb-frontends/tda1004x.c
+++ b/drivers/media/dvb-frontends/tda1004x.c
@@ -1299,20 +1299,22 @@ struct dvb_frontend* tda10045_attach(const struct tda1004x_config* config,
 	id = tda1004x_read_byte(state, TDA1004X_CHIPID);
 	if (id < 0) {
 		printk(KERN_ERR "tda10045: chip is not answering. Giving up.\n");
-		kfree(state);
-		return NULL;
+		goto free_state;
 	}
 
 	if (id != 0x25) {
 		printk(KERN_ERR "Invalid tda1004x ID = 0x%02x. Can't proceed\n", id);
-		kfree(state);
-		return NULL;
+		goto free_state;
 	}
 
 	/* create dvb_frontend */
 	memcpy(&state->frontend.ops, &tda10045_ops, sizeof(struct dvb_frontend_ops));
 	state->frontend.demodulator_priv = state;
 	return &state->frontend;
+
+free_state:
+	kfree(state);
+	return NULL;
 }
 
 static const struct dvb_frontend_ops tda10046_ops = {
@@ -1369,19 +1371,21 @@ struct dvb_frontend* tda10046_attach(const struct tda1004x_config* config,
 	id = tda1004x_read_byte(state, TDA1004X_CHIPID);
 	if (id < 0) {
 		printk(KERN_ERR "tda10046: chip is not answering. Giving up.\n");
-		kfree(state);
-		return NULL;
+		goto free_state;
 	}
 	if (id != 0x46) {
 		printk(KERN_ERR "Invalid tda1004x ID = 0x%02x. Can't proceed\n", id);
-		kfree(state);
-		return NULL;
+		goto free_state;
 	}
 
 	/* create dvb_frontend */
 	memcpy(&state->frontend.ops, &tda10046_ops, sizeof(struct dvb_frontend_ops));
 	state->frontend.demodulator_priv = state;
 	return &state->frontend;
+
+free_state:
+	kfree(state);
+	return NULL;
 }
 
 module_param(debug, int, 0644);
diff --git a/drivers/media/dvb-frontends/tda8261.c b/drivers/media/dvb-frontends/tda8261.c
index f72a54e7eb23..7b9a29939b74 100644
--- a/drivers/media/dvb-frontends/tda8261.c
+++ b/drivers/media/dvb-frontends/tda8261.c
@@ -129,18 +129,17 @@ static int tda8261_set_params(struct dvb_frontend *fe)
 
 	/* Set params */
 	err = tda8261_write(state, buf);
-	if (err < 0) {
-		pr_err("%s: I/O Error\n", __func__);
-		return err;
-	}
+	if (err < 0)
+		goto report_failure;
+
 	/* sleep for some time */
 	pr_debug("%s: Waiting to Phase LOCK\n", __func__);
 	msleep(20);
 	/* check status */
-	if ((err = tda8261_get_status(fe, &status)) < 0) {
-		pr_err("%s: I/O Error\n", __func__);
-		return err;
-	}
+	err = tda8261_get_status(fe, &status);
+	if (err < 0)
+		goto report_failure;
+
 	if (status == 1) {
 		pr_debug("%s: Tuner Phase locked: status=%d\n", __func__,
 			 status);
@@ -150,6 +149,10 @@ static int tda8261_set_params(struct dvb_frontend *fe)
 	}
 
 	return 0;
+
+report_failure:
+	pr_err("%s: I/O Error\n", __func__);
+	return err;
 }
 
 static void tda8261_release(struct dvb_frontend *fe)
diff --git a/drivers/media/pci/bt8xx/dst.c b/drivers/media/pci/bt8xx/dst.c
index 4f0bba9e4c48..7014cb6a0ad6 100644
--- a/drivers/media/pci/bt8xx/dst.c
+++ b/drivers/media/pci/bt8xx/dst.c
@@ -134,17 +134,20 @@ EXPORT_SYMBOL(rdc_reset_state);
 static int rdc_8820_reset(struct dst_state *state)
 {
 	dprintk(3, "Resetting DST\n");
-	if (dst_gpio_outb(state, RDC_8820_RESET, RDC_8820_RESET, 0, NO_DELAY) < 0) {
-		pr_err("dst_gpio_outb ERROR !\n");
-		return -1;
-	}
+	if (dst_gpio_outb(state, RDC_8820_RESET, RDC_8820_RESET, 0, NO_DELAY)
+	    < 0)
+		goto report_failure;
+
 	udelay(1000);
-	if (dst_gpio_outb(state, RDC_8820_RESET, RDC_8820_RESET, RDC_8820_RESET, DELAY) < 0) {
-		pr_err("dst_gpio_outb ERROR !\n");
-		return -1;
-	}
+	if (dst_gpio_outb(state, RDC_8820_RESET, RDC_8820_RESET,
+			  RDC_8820_RESET, DELAY) < 0)
+		goto report_failure;
 
 	return 0;
+
+report_failure:
+	pr_err("dst_gpio_outb ERROR !\n");
+	return -1;
 }
 
 static int dst_pio_enable(struct dst_state *state)
diff --git a/drivers/media/pci/bt8xx/dst_ca.c b/drivers/media/pci/bt8xx/dst_ca.c
index 0a7623c0fc8e..26e05a8457e6 100644
--- a/drivers/media/pci/bt8xx/dst_ca.c
+++ b/drivers/media/pci/bt8xx/dst_ca.c
@@ -83,33 +83,33 @@ static int dst_ci_command(struct dst_state* state, u8 * data, u8 *ca_string, u8
 
 	if (write_dst(state, data, len)) {
 		dprintk(verbose, DST_CA_INFO, 1, " Write not successful, trying to recover");
-		dst_error_recovery(state);
-		goto error;
+		goto error_recovery;
 	}
 	if ((dst_pio_disable(state)) < 0) {
 		dprintk(verbose, DST_CA_ERROR, 1, " DST PIO disable failed.");
-		goto error;
-	}
-	if (read_dst(state, &reply, GET_ACK) < 0) {
-		dprintk(verbose, DST_CA_INFO, 1, " Read not successful, trying to recover");
-		dst_error_recovery(state);
-		goto error;
+		goto unlock;
 	}
+	if (read_dst(state, &reply, GET_ACK) < 0)
+		goto report_read_failure;
+
 	if (read) {
 		if (! dst_wait_dst_ready(state, LONG_DELAY)) {
 			dprintk(verbose, DST_CA_NOTICE, 1, " 8820 not ready");
-			goto error;
-		}
-		if (read_dst(state, ca_string, 128) < 0) {	/*	Try to make this dynamic	*/
-			dprintk(verbose, DST_CA_INFO, 1, " Read not successful, trying to recover");
-			dst_error_recovery(state);
-			goto error;
+			goto unlock;
 		}
+		/* Try to make this dynamic */
+		if (read_dst(state, ca_string, 128) < 0)
+			goto report_read_failure;
 	}
 	mutex_unlock(&state->dst_mutex);
 	return 0;
 
-error:
+report_read_failure:
+	dprintk(verbose, DST_CA_INFO, 1,
+		" Read not successful, trying to recover");
+error_recovery:
+	dst_error_recovery(state);
+unlock:
 	mutex_unlock(&state->dst_mutex);
 	return -EIO;
 }
diff --git a/drivers/media/pci/cx88/cx88-input.c b/drivers/media/pci/cx88/cx88-input.c
index 4e9953e61a12..c972efcd6bb6 100644
--- a/drivers/media/pci/cx88/cx88-input.c
+++ b/drivers/media/pci/cx88/cx88-input.c
@@ -566,20 +566,17 @@ static int get_key_pvr2000(struct IR_i2c *ir, enum rc_proto *protocol,
 
 	/* poll IR chip */
 	flags = i2c_smbus_read_byte_data(ir->c, 0x10);
-	if (flags < 0) {
-		dprintk("read error\n");
-		return 0;
-	}
+	if (flags < 0)
+		goto report_read_failure;
+
 	/* key pressed ? */
 	if (0 == (flags & 0x80))
 		return 0;
 
 	/* read actual key code */
 	code = i2c_smbus_read_byte_data(ir->c, 0x00);
-	if (code < 0) {
-		dprintk("read error\n");
-		return 0;
-	}
+	if (code < 0)
+		goto report_read_failure;
 
 	dprintk("IR Key/Flags: (0x%02x/0x%02x)\n",
 		code & 0xff, flags & 0xff);
@@ -588,6 +585,10 @@ static int get_key_pvr2000(struct IR_i2c *ir, enum rc_proto *protocol,
 	*scancode = code & 0xff;
 	*toggle = 0;
 	return 1;
+
+report_read_failure:
+	dprintk("read error\n");
+	return 0;
 }
 
 void cx88_i2c_init_ir(struct cx88_core *core)
diff --git a/drivers/media/platform/omap3isp/ispvideo.c b/drivers/media/platform/omap3isp/ispvideo.c
index a751c89a3ea8..2ddcac736402 100644
--- a/drivers/media/platform/omap3isp/ispvideo.c
+++ b/drivers/media/platform/omap3isp/ispvideo.c
@@ -1315,14 +1315,12 @@ static int isp_video_open(struct file *file)
 	/* If this is the first user, initialise the pipeline. */
 	if (omap3isp_get(video->isp) == NULL) {
 		ret = -EBUSY;
-		goto done;
+		goto delete_fh;
 	}
 
 	ret = v4l2_pipeline_pm_use(&video->video.entity, 1);
-	if (ret < 0) {
-		omap3isp_put(video->isp);
-		goto done;
-	}
+	if (ret < 0)
+		goto put_isp;
 
 	queue = &handle->queue;
 	queue->type = video->type;
@@ -1335,10 +1333,8 @@ static int isp_video_open(struct file *file)
 	queue->dev = video->isp->dev;
 
 	ret = vb2_queue_init(&handle->queue);
-	if (ret < 0) {
-		omap3isp_put(video->isp);
-		goto done;
-	}
+	if (ret < 0)
+		goto put_isp;
 
 	memset(&handle->format, 0, sizeof(handle->format));
 	handle->format.type = video->type;
@@ -1346,14 +1342,15 @@ static int isp_video_open(struct file *file)
 
 	handle->video = video;
 	file->private_data = &handle->vfh;
+	goto exit;
 
-done:
-	if (ret < 0) {
-		v4l2_fh_del(&handle->vfh);
-		v4l2_fh_exit(&handle->vfh);
-		kfree(handle);
-	}
-
+put_isp:
+	omap3isp_put(video->isp);
+delete_fh:
+	v4l2_fh_del(&handle->vfh);
+	v4l2_fh_exit(&handle->vfh);
+	kfree(handle);
+exit:
 	return ret;
 }
 
diff --git a/drivers/media/platform/qcom/camss-8x16/camss-csid.c b/drivers/media/platform/qcom/camss-8x16/camss-csid.c
index 64df82817de3..92d4dc6b4a66 100644
--- a/drivers/media/platform/qcom/camss-8x16/camss-csid.c
+++ b/drivers/media/platform/qcom/camss-8x16/camss-csid.c
@@ -328,16 +328,12 @@ static int csid_set_power(struct v4l2_subdev *sd, int on)
 			return ret;
 
 		ret = csid_set_clock_rates(csid);
-		if (ret < 0) {
-			regulator_disable(csid->vdda);
-			return ret;
-		}
+		if (ret < 0)
+			goto disable_regulator;
 
 		ret = camss_enable_clocks(csid->nclocks, csid->clock, dev);
-		if (ret < 0) {
-			regulator_disable(csid->vdda);
-			return ret;
-		}
+		if (ret < 0)
+			goto disable_regulator;
 
 		enable_irq(csid->irq);
 
@@ -345,8 +341,7 @@ static int csid_set_power(struct v4l2_subdev *sd, int on)
 		if (ret < 0) {
 			disable_irq(csid->irq);
 			camss_disable_clocks(csid->nclocks, csid->clock);
-			regulator_disable(csid->vdda);
-			return ret;
+			goto disable_regulator;
 		}
 
 		hw_version = readl_relaxed(csid->base + CAMSS_CSID_HW_VERSION);
@@ -357,6 +352,11 @@ static int csid_set_power(struct v4l2_subdev *sd, int on)
 		ret = regulator_disable(csid->vdda);
 	}
 
+	goto exit;
+
+disable_regulator:
+	regulator_disable(csid->vdda);
+exit:
 	return ret;
 }
 
diff --git a/drivers/media/tuners/tuner-xc2028.c b/drivers/media/tuners/tuner-xc2028.c
index fca85e08ebd7..2199b04c0ba9 100644
--- a/drivers/media/tuners/tuner-xc2028.c
+++ b/drivers/media/tuners/tuner-xc2028.c
@@ -571,7 +571,7 @@ static int load_firmware(struct dvb_frontend *fe, unsigned int type,
 		/* Checks if there's enough bytes to read */
 		if (p + sizeof(size) > endp) {
 			tuner_err("Firmware chunk size is wrong\n");
-			return -EINVAL;
+			goto e_inval;
 		}
 
 		size = le16_to_cpu(*(__le16 *) p);
@@ -583,28 +583,23 @@ static int load_firmware(struct dvb_frontend *fe, unsigned int type,
 		if (!size) {
 			/* Special callback command received */
 			rc = do_tuner_callback(fe, XC2028_TUNER_RESET, 0);
-			if (rc < 0) {
-				tuner_err("Error at RESET code %d\n",
-					   (*p) & 0x7f);
-				return -EINVAL;
-			}
+			if (rc < 0)
+				goto report_failure;
+
 			continue;
 		}
 		if (size >= 0xff00) {
 			switch (size) {
 			case 0xff00:
 				rc = do_tuner_callback(fe, XC2028_RESET_CLK, 0);
-				if (rc < 0) {
-					tuner_err("Error at RESET code %d\n",
-						  (*p) & 0x7f);
-					return -EINVAL;
-				}
+				if (rc < 0)
+					goto report_failure;
+
 				break;
 			default:
 				tuner_info("Invalid RESET code %d\n",
 					   size & 0x7f);
-				return -EINVAL;
-
+				goto e_inval;
 			}
 			continue;
 		}
@@ -618,7 +613,7 @@ static int load_firmware(struct dvb_frontend *fe, unsigned int type,
 		if ((size + p > endp)) {
 			tuner_err("missing bytes: need %d, have %d\n",
 				   size, (int)(endp - p));
-			return -EINVAL;
+			goto e_inval;
 		}
 
 		buf[0] = *p;
@@ -635,7 +630,7 @@ static int load_firmware(struct dvb_frontend *fe, unsigned int type,
 			rc = i2c_send(priv, buf, len + 1);
 			if (rc < 0) {
 				tuner_err("%d returned from send\n", rc);
-				return -EINVAL;
+				goto e_inval;
 			}
 
 			p += len;
@@ -650,6 +645,11 @@ static int load_firmware(struct dvb_frontend *fe, unsigned int type,
 		}
 	}
 	return 0;
+
+report_failure:
+	tuner_err("Error at RESET code %d\n", (*p) & 0x7f);
+e_inval:
+	return -EINVAL;
 }
 
 static int load_scode(struct dvb_frontend *fe, unsigned int type,
diff --git a/drivers/media/usb/cpia2/cpia2_usb.c b/drivers/media/usb/cpia2/cpia2_usb.c
index f3a1e5b1e57c..c6eaecbac831 100644
--- a/drivers/media/usb/cpia2/cpia2_usb.c
+++ b/drivers/media/usb/cpia2/cpia2_usb.c
@@ -848,15 +848,13 @@ static int cpia2_usb_probe(struct usb_interface *intf,
 	ret = set_alternate(cam, USBIF_CMDONLY);
 	if (ret < 0) {
 		ERR("%s: usb_set_interface error (ret = %d)\n", __func__, ret);
-		kfree(cam);
-		return ret;
+		goto free_data;
 	}
 
 
 	if((ret = cpia2_init_camera(cam)) < 0) {
 		ERR("%s: failed to initialize cpia2 camera (ret = %d)\n", __func__, ret);
-		kfree(cam);
-		return ret;
+		goto free_data;
 	}
 	LOG("  CPiA Version: %d.%02d (%d.%d)\n",
 	       cam->params.version.firmware_revision_hi,
@@ -876,11 +874,14 @@ static int cpia2_usb_probe(struct usb_interface *intf,
 	ret = cpia2_register_camera(cam);
 	if (ret < 0) {
 		ERR("%s: Failed to register cpia2 camera (ret = %d)\n", __func__, ret);
-		kfree(cam);
-		return ret;
+		goto free_data;
 	}
 
 	return 0;
+
+free_data:
+	kfree(cam);
+	return ret;
 }
 
 /******************************************************************************
diff --git a/drivers/media/usb/gspca/gspca.c b/drivers/media/usb/gspca/gspca.c
index d29773b8f696..7ca44e109a69 100644
--- a/drivers/media/usb/gspca/gspca.c
+++ b/drivers/media/usb/gspca/gspca.c
@@ -907,10 +907,8 @@ static int gspca_init_transfer(struct gspca_dev *gspca_dev)
 			ret = create_urbs(gspca_dev,
 				alt_xfer(&intf->altsetting[alt], xfer,
 					 gspca_dev->xfer_ep));
-			if (ret < 0) {
-				destroy_urbs(gspca_dev);
-				goto out;
-			}
+			if (ret < 0)
+				goto destroy_urbs;
 		}
 
 		/* clear the bulk endpoint */
@@ -920,10 +918,9 @@ static int gspca_init_transfer(struct gspca_dev *gspca_dev)
 
 		/* start the cam */
 		ret = gspca_dev->sd_desc->start(gspca_dev);
-		if (ret < 0) {
-			destroy_urbs(gspca_dev);
-			goto out;
-		}
+		if (ret < 0)
+			goto destroy_urbs;
+
 		gspca_dev->streaming = 1;
 		v4l2_ctrl_handler_setup(gspca_dev->vdev.ctrl_handler);
 
@@ -974,6 +971,10 @@ static int gspca_init_transfer(struct gspca_dev *gspca_dev)
 out:
 	gspca_input_create_urb(gspca_dev);
 	return ret;
+
+destroy_urbs:
+	destroy_urbs(gspca_dev);
+	goto out;
 }
 
 static void gspca_set_default_mode(struct gspca_dev *gspca_dev)
diff --git a/drivers/media/usb/gspca/sn9c20x.c b/drivers/media/usb/gspca/sn9c20x.c
index cfa2a04d9f3f..06ec3a3253e1 100644
--- a/drivers/media/usb/gspca/sn9c20x.c
+++ b/drivers/media/usb/gspca/sn9c20x.c
@@ -1788,10 +1788,8 @@ static int sd_init(struct gspca_dev *gspca_dev)
 	for (i = 0; i < ARRAY_SIZE(bridge_init); i++) {
 		value = bridge_init[i][1];
 		reg_w(gspca_dev, bridge_init[i][0], &value, 1);
-		if (gspca_dev->usb_err < 0) {
-			pr_err("Device initialization failed\n");
-			return gspca_dev->usb_err;
-		}
+		if (gspca_dev->usb_err < 0)
+			goto report_failure;
 	}
 
 	if (sd->flags & LED_REVERSE)
@@ -1800,10 +1798,8 @@ static int sd_init(struct gspca_dev *gspca_dev)
 		reg_w1(gspca_dev, 0x1006, 0x20);
 
 	reg_w(gspca_dev, 0x10c0, i2c_init, 9);
-	if (gspca_dev->usb_err < 0) {
-		pr_err("Device initialization failed\n");
-		return gspca_dev->usb_err;
-	}
+	if (gspca_dev->usb_err < 0)
+		goto report_failure;
 
 	switch (sd->sensor) {
 	case SENSOR_OV9650:
@@ -1869,6 +1865,11 @@ static int sd_init(struct gspca_dev *gspca_dev)
 		pr_err("Unsupported sensor\n");
 		gspca_dev->usb_err = -ENODEV;
 	}
+	goto exit;
+
+report_failure:
+	pr_err("Device initialization failed\n");
+exit:
 	return gspca_dev->usb_err;
 }
 
diff --git a/drivers/media/usb/pvrusb2/pvrusb2-ioread.c b/drivers/media/usb/pvrusb2/pvrusb2-ioread.c
index 602097bdcf14..0218614ce988 100644
--- a/drivers/media/usb/pvrusb2/pvrusb2-ioread.c
+++ b/drivers/media/usb/pvrusb2/pvrusb2-ioread.c
@@ -266,8 +266,7 @@ static int pvr2_ioread_get_buffer(struct pvr2_ioread *cp)
 				pvr2_trace(PVR2_TRACE_DATA_FLOW,
 					   "/*---TRACE_READ---*/ pvr2_ioread_read id=%p queue_error=%d",
 					   cp,stat);
-				pvr2_ioread_stop(cp);
-				return 0;
+				goto stop_read;
 			}
 			cp->c_buf = NULL;
 			cp->c_data_ptr = NULL;
@@ -286,9 +285,8 @@ static int pvr2_ioread_get_buffer(struct pvr2_ioread *cp)
 				pvr2_trace(PVR2_TRACE_DATA_FLOW,
 					   "/*---TRACE_READ---*/ pvr2_ioread_read id=%p buffer_error=%d",
 					   cp,stat);
-				pvr2_ioread_stop(cp);
 				// Give up.
-				return 0;
+				goto stop_read;
 			}
 			// Start over...
 			continue;
@@ -298,6 +296,10 @@ static int pvr2_ioread_get_buffer(struct pvr2_ioread *cp)
 			pvr2_buffer_get_id(cp->c_buf)];
 	}
 	return !0;
+
+stop_read:
+	pvr2_ioread_stop(cp);
+	return 0;
 }
 
 static void pvr2_ioread_filter(struct pvr2_ioread *cp)
diff --git a/drivers/media/usb/tm6000/tm6000-cards.c b/drivers/media/usb/tm6000/tm6000-cards.c
index 4d5f4cc4887e..e5c376a6495a 100644
--- a/drivers/media/usb/tm6000/tm6000-cards.c
+++ b/drivers/media/usb/tm6000/tm6000-cards.c
@@ -861,15 +861,14 @@ int tm6000_cards_setup(struct tm6000_core *dev)
 		for (i = 0; i < 2; i++) {
 			rc = tm6000_set_reg(dev, REQ_03_SET_GET_MCU_PIN,
 						dev->gpio.tuner_reset, 0x00);
-			if (rc < 0) {
-				printk(KERN_ERR "Error %i doing tuner reset\n", rc);
-				return rc;
-			}
+			if (rc < 0)
+				goto report_failure;
 
 			msleep(10); /* Just to be conservative */
 			rc = tm6000_set_reg(dev, REQ_03_SET_GET_MCU_PIN,
 						dev->gpio.tuner_reset, 0x01);
 			if (rc < 0) {
+report_failure:
 				printk(KERN_ERR "Error %i doing tuner reset\n", rc);
 				return rc;
 			}
diff --git a/drivers/media/usb/tm6000/tm6000-dvb.c b/drivers/media/usb/tm6000/tm6000-dvb.c
index c811fc6cf48a..7cc5c5aa08c2 100644
--- a/drivers/media/usb/tm6000/tm6000-dvb.c
+++ b/drivers/media/usb/tm6000/tm6000-dvb.c
@@ -134,8 +134,8 @@ static int tm6000_start_stream(struct tm6000_core *dev)
 
 	dvb->bulk_urb->transfer_buffer = kzalloc(size, GFP_KERNEL);
 	if (!dvb->bulk_urb->transfer_buffer) {
-		usb_free_urb(dvb->bulk_urb);
-		return -ENOMEM;
+		ret = -ENOMEM;
+		goto free_urb;
 	}
 
 	usb_fill_bulk_urb(dvb->bulk_urb, dev->udev, pipe,
@@ -160,11 +160,14 @@ static int tm6000_start_stream(struct tm6000_core *dev)
 									ret);
 
 		kfree(dvb->bulk_urb->transfer_buffer);
-		usb_free_urb(dvb->bulk_urb);
-		return ret;
+		goto free_urb;
 	}
 
 	return 0;
+
+free_urb:
+	usb_free_urb(dvb->bulk_urb);
+	return ret;
 }
 
 static void tm6000_stop_stream(struct tm6000_core *dev)
diff --git a/drivers/media/usb/tm6000/tm6000-video.c b/drivers/media/usb/tm6000/tm6000-video.c
index 8314d3fa9241..7c1d5e259ea3 100644
--- a/drivers/media/usb/tm6000/tm6000-video.c
+++ b/drivers/media/usb/tm6000/tm6000-video.c
@@ -589,10 +589,8 @@ static int tm6000_prepare_isoc(struct tm6000_core *dev)
 
 	dev->isoc_ctl.transfer_buffer = kmalloc(sizeof(void *)*num_bufs,
 				   GFP_KERNEL);
-	if (!dev->isoc_ctl.transfer_buffer) {
-		kfree(dev->isoc_ctl.urb);
-		return -ENOMEM;
-	}
+	if (!dev->isoc_ctl.transfer_buffer)
+		goto free_urb;
 
 	dprintk(dev, V4L2_DEBUG_QUEUE, "Allocating %d x %d packets (%d bytes) of %d bytes each to handle %u size\n",
 		    max_packets, num_bufs, sb_size,
@@ -604,9 +602,8 @@ static int tm6000_prepare_isoc(struct tm6000_core *dev)
 
 		/* call free, as some buffers might have been allocated */
 		tm6000_free_urb_buffers(dev);
-		kfree(dev->isoc_ctl.urb);
 		kfree(dev->isoc_ctl.transfer_buffer);
-		return -ENOMEM;
+		goto free_urb;
 	}
 
 	/* allocate urbs and transfer buffers */
@@ -636,6 +633,10 @@ static int tm6000_prepare_isoc(struct tm6000_core *dev)
 	}
 
 	return 0;
+
+free_urb:
+	kfree(dev->isoc_ctl.urb);
+	return -ENOMEM;
 }
 
 static int tm6000_start_thread(struct tm6000_core *dev)
diff --git a/drivers/media/usb/ttusb-budget/dvb-ttusb-budget.c b/drivers/media/usb/ttusb-budget/dvb-ttusb-budget.c
index eed56895c2b9..b093a843644b 100644
--- a/drivers/media/usb/ttusb-budget/dvb-ttusb-budget.c
+++ b/drivers/media/usb/ttusb-budget/dvb-ttusb-budget.c
@@ -1665,8 +1665,7 @@ static int ttusb_probe(struct usb_interface *intf, const struct usb_device_id *i
 	if (result < 0) {
 		dprintk("%s: ttusb_alloc_iso_urbs - failed\n", __func__);
 		mutex_unlock(&ttusb->semi2c);
-		kfree(ttusb);
-		return result;
+		goto err_free_usb;
 	}
 
 	if (ttusb_init_controller(ttusb))
@@ -1677,11 +1676,9 @@ static int ttusb_probe(struct usb_interface *intf, const struct usb_device_id *i
 	result = dvb_register_adapter(&ttusb->adapter,
 				      "Technotrend/Hauppauge Nova-USB",
 				      THIS_MODULE, &udev->dev, adapter_nr);
-	if (result < 0) {
-		ttusb_free_iso_urbs(ttusb);
-		kfree(ttusb);
-		return result;
-	}
+	if (result < 0)
+		goto err_free_iso_urbs;
+
 	ttusb->adapter.priv = ttusb;
 
 	/* i2c */
@@ -1752,7 +1749,9 @@ static int ttusb_probe(struct usb_interface *intf, const struct usb_device_id *i
 	i2c_del_adapter(&ttusb->i2c_adap);
 err_unregister_adapter:
 	dvb_unregister_adapter (&ttusb->adapter);
+err_free_iso_urbs:
 	ttusb_free_iso_urbs(ttusb);
+err_free_usb:
 	kfree(ttusb);
 	return result;
 }
diff --git a/drivers/media/usb/ttusb-dec/ttusb_dec.c b/drivers/media/usb/ttusb-dec/ttusb_dec.c
index a8900f5571f7..99095b025859 100644
--- a/drivers/media/usb/ttusb-dec/ttusb_dec.c
+++ b/drivers/media/usb/ttusb-dec/ttusb_dec.c
@@ -1498,10 +1498,7 @@ static int ttusb_dec_init_dvb(struct ttusb_dec *dec)
 	if ((result = dvb_dmx_init(&dec->demux)) < 0) {
 		printk("%s: dvb_dmx_init failed: error %d\n", __func__,
 		       result);
-
-		dvb_unregister_adapter(&dec->adapter);
-
-		return result;
+		goto unregister_adapter;
 	}
 
 	dec->dmxdev.filternum = 32;
@@ -1511,43 +1508,33 @@ static int ttusb_dec_init_dvb(struct ttusb_dec *dec)
 	if ((result = dvb_dmxdev_init(&dec->dmxdev, &dec->adapter)) < 0) {
 		printk("%s: dvb_dmxdev_init failed: error %d\n",
 		       __func__, result);
-
-		dvb_dmx_release(&dec->demux);
-		dvb_unregister_adapter(&dec->adapter);
-
-		return result;
+		goto release_demux;
 	}
 
 	dec->frontend.source = DMX_FRONTEND_0;
 
-	if ((result = dec->demux.dmx.add_frontend(&dec->demux.dmx,
-						  &dec->frontend)) < 0) {
-		printk("%s: dvb_dmx_init failed: error %d\n", __func__,
-		       result);
-
-		dvb_dmxdev_release(&dec->dmxdev);
-		dvb_dmx_release(&dec->demux);
-		dvb_unregister_adapter(&dec->adapter);
-
-		return result;
-	}
+	result = dec->demux.dmx.add_frontend(&dec->demux.dmx, &dec->frontend);
+	if (result < 0)
+		goto report_failure;
 
 	if ((result = dec->demux.dmx.connect_frontend(&dec->demux.dmx,
 						      &dec->frontend)) < 0) {
-		printk("%s: dvb_dmx_init failed: error %d\n", __func__,
-		       result);
-
 		dec->demux.dmx.remove_frontend(&dec->demux.dmx, &dec->frontend);
-		dvb_dmxdev_release(&dec->dmxdev);
-		dvb_dmx_release(&dec->demux);
-		dvb_unregister_adapter(&dec->adapter);
-
-		return result;
+		goto report_failure;
 	}
 
 	dvb_net_init(&dec->adapter, &dec->dvb_net, &dec->demux.dmx);
 
 	return 0;
+
+report_failure:
+	printk("%s: dvb_dmx_init failed: error %d\n", __func__, result);
+	dvb_dmxdev_release(&dec->dmxdev);
+release_demux:
+	dvb_dmx_release(&dec->demux);
+unregister_adapter:
+	dvb_unregister_adapter(&dec->adapter);
+	return result;
 }
 
 static void ttusb_dec_exit_dvb(struct ttusb_dec *dec)
diff --git a/drivers/media/usb/uvc/uvc_v4l2.c b/drivers/media/usb/uvc/uvc_v4l2.c
index a13ad4e178be..f64c851adea2 100644
--- a/drivers/media/usb/uvc/uvc_v4l2.c
+++ b/drivers/media/usb/uvc/uvc_v4l2.c
@@ -994,10 +994,8 @@ static int uvc_ioctl_g_ext_ctrls(struct file *file, void *fh,
 			struct v4l2_queryctrl qc = { .id = ctrl->id };
 
 			ret = uvc_query_v4l2_ctrl(chain, &qc);
-			if (ret < 0) {
-				ctrls->error_idx = i;
-				return ret;
-			}
+			if (ret < 0)
+				goto set_index;
 
 			ctrl->value = qc.default_value;
 		}
@@ -1013,14 +1011,17 @@ static int uvc_ioctl_g_ext_ctrls(struct file *file, void *fh,
 		ret = uvc_ctrl_get(chain, ctrl);
 		if (ret < 0) {
 			uvc_ctrl_rollback(handle);
-			ctrls->error_idx = i;
-			return ret;
+			goto set_index;
 		}
 	}
 
 	ctrls->error_idx = 0;
 
 	return uvc_ctrl_rollback(handle);
+
+set_index:
+	ctrls->error_idx = i;
+	return ret;
 }
 
 static int uvc_ioctl_s_try_ext_ctrls(struct uvc_fh *handle,
-- 
2.16.1

^ permalink raw reply	[flat|nested] 10+ messages in thread

* Re: [PATCH v2] [media] Use common error handling code in 20 functions
  2018-02-19 18:11 [PATCH v2] [media] Use common error handling code in 20 functions SF Markus Elfring
@ 2018-02-19 18:37 ` Laurent Pinchart
  2018-02-28  8:45   ` [v2] " SF Markus Elfring
  2018-02-20  8:07 ` [PATCH v2] " Todor Tomov
  2018-03-09 20:10 ` [PATCH v3] [media] Use common error handling code in 19 functions SF Markus Elfring
  2 siblings, 1 reply; 10+ messages in thread
From: Laurent Pinchart @ 2018-02-19 18:37 UTC (permalink / raw)
  To: SF Markus Elfring
  Cc: linux-media, Al Viro, Andi Shyti, Andrew Morton, Andrey Utkin,
	Arvind Yadav, Bhumika Goyal, Bjorn Helgaas, Brian Johnson,
	Christoph Böhmwalder, Christophe Jaillet, Colin Ian King,
	Daniele Nicolodi, David Härdeman, Devendra Sharma,
	Gustavo A. R. Silva, Hans Verkuil, Inki Dae, Joe Perches,
	Kees Cook, Masahiro Yamada, Mauro Carvalho Chehab,
	Max Kellermann, Mike Isely, Philippe Ombredanne, Sakari Ailus,
	Santosh Kumar Singh, Satendra Singh Thakur, Sean Young,
	Seung-Woo Kim, Shyam Saini, Thomas Gleixner, Todor Tomov,
	Wei Yongjun, LKML, kernel-janitors

Hello Markus,

On Monday, 19 February 2018 20:11:56 EET SF Markus Elfring wrote:
> From: Markus Elfring <elfring@users.sourceforge.net>
> Date: Mon, 19 Feb 2018 18:50:40 +0100
> 
> Adjust jump targets so that a bit of exception handling can be better
> reused at the end of these functions.
> 
> This issue was partly detected by using the Coccinelle software.
> 
> Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
> ---
> 
> v2:
> Hans Verkuil insisted on patch squashing. Thus several changes
> were recombined based on source files from Linux next-20180216.
> 
> The implementation of the function "tda8261_set_params" was improved
> after a notification by Christoph Böhmwalder on 2017-09-26.
> 
>  drivers/media/dvb-core/dmxdev.c                    | 16 ++++----
>  drivers/media/dvb-frontends/tda1004x.c             | 20 ++++++----
>  drivers/media/dvb-frontends/tda8261.c              | 19 ++++++----
>  drivers/media/pci/bt8xx/dst.c                      | 19 ++++++----
>  drivers/media/pci/bt8xx/dst_ca.c                   | 30 +++++++--------
>  drivers/media/pci/cx88/cx88-input.c                | 17 +++++----
>  drivers/media/platform/omap3isp/ispvideo.c         | 29 +++++++--------
>  .../media/platform/qcom/camss-8x16/camss-csid.c    | 20 +++++-----
>  drivers/media/tuners/tuner-xc2028.c                | 30 +++++++--------
>  drivers/media/usb/cpia2/cpia2_usb.c                | 13 ++++---
>  drivers/media/usb/gspca/gspca.c                    | 17 +++++----
>  drivers/media/usb/gspca/sn9c20x.c                  | 17 +++++----
>  drivers/media/usb/pvrusb2/pvrusb2-ioread.c         | 10 +++--
>  drivers/media/usb/tm6000/tm6000-cards.c            |  7 ++--
>  drivers/media/usb/tm6000/tm6000-dvb.c              | 11 ++++--
>  drivers/media/usb/tm6000/tm6000-video.c            | 13 ++++---
>  drivers/media/usb/ttusb-budget/dvb-ttusb-budget.c  | 13 +++----
>  drivers/media/usb/ttusb-dec/ttusb_dec.c            | 43 +++++++------------
>  drivers/media/usb/uvc/uvc_v4l2.c                   | 13 ++++---
>  19 files changed, 180 insertions(+), 177 deletions(-)

[snip]

> diff --git a/drivers/media/platform/omap3isp/ispvideo.c
> b/drivers/media/platform/omap3isp/ispvideo.c index
> a751c89a3ea8..2ddcac736402 100644
> --- a/drivers/media/platform/omap3isp/ispvideo.c
> +++ b/drivers/media/platform/omap3isp/ispvideo.c
> @@ -1315,14 +1315,12 @@ static int isp_video_open(struct file *file)
>  	/* If this is the first user, initialise the pipeline. */
>  	if (omap3isp_get(video->isp) == NULL) {
>  		ret = -EBUSY;
> -		goto done;
> +		goto delete_fh;
>  	}
> 
>  	ret = v4l2_pipeline_pm_use(&video->video.entity, 1);
> -	if (ret < 0) {
> -		omap3isp_put(video->isp);
> -		goto done;
> -	}
> +	if (ret < 0)
> +		goto put_isp;
> 
>  	queue = &handle->queue;
>  	queue->type = video->type;
> @@ -1335,10 +1333,8 @@ static int isp_video_open(struct file *file)
>  	queue->dev = video->isp->dev;
> 
>  	ret = vb2_queue_init(&handle->queue);
> -	if (ret < 0) {
> -		omap3isp_put(video->isp);
> -		goto done;
> -	}
> +	if (ret < 0)
> +		goto put_isp;
> 
>  	memset(&handle->format, 0, sizeof(handle->format));
>  	handle->format.type = video->type;
> @@ -1346,14 +1342,15 @@ static int isp_video_open(struct file *file)
> 
>  	handle->video = video;
>  	file->private_data = &handle->vfh;
> +	goto exit;

No need for a goto here, you can just return 0.

> 
> -done:
> -	if (ret < 0) {
> -		v4l2_fh_del(&handle->vfh);
> -		v4l2_fh_exit(&handle->vfh);
> -		kfree(handle);
> -	}
> -
> +put_isp:
> +	omap3isp_put(video->isp);
> +delete_fh:
> +	v4l2_fh_del(&handle->vfh);
> +	v4l2_fh_exit(&handle->vfh);
> +	kfree(handle);

Please prefix the error labels with error_.

> +exit:
>  	return ret;
>  }
> 

Otherwise the changes to omap3isp look OK to me.

[snip]

> diff --git a/drivers/media/usb/uvc/uvc_v4l2.c
> b/drivers/media/usb/uvc/uvc_v4l2.c index a13ad4e178be..f64c851adea2 100644
> --- a/drivers/media/usb/uvc/uvc_v4l2.c
> +++ b/drivers/media/usb/uvc/uvc_v4l2.c
> @@ -994,10 +994,8 @@ static int uvc_ioctl_g_ext_ctrls(struct file *file,
> void *fh, struct v4l2_queryctrl qc = { .id = ctrl->id };
> 
>  			ret = uvc_query_v4l2_ctrl(chain, &qc);
> -			if (ret < 0) {
> -				ctrls->error_idx = i;
> -				return ret;
> -			}
> +			if (ret < 0)
> +				goto set_index;
> 
>  			ctrl->value = qc.default_value;
>  		}
> @@ -1013,14 +1011,17 @@ static int uvc_ioctl_g_ext_ctrls(struct file *file,
> void *fh, ret = uvc_ctrl_get(chain, ctrl);
>  		if (ret < 0) {
>  			uvc_ctrl_rollback(handle);
> -			ctrls->error_idx = i;
> -			return ret;
> +			goto set_index;
>  		}
>  	}
> 
>  	ctrls->error_idx = 0;
> 
>  	return uvc_ctrl_rollback(handle);
> +
> +set_index:
> +	ctrls->error_idx = i;
> +	return ret;
>  }

For uvcvideo I find this to hinder readability without adding much added 
value. Please drop the uvcvideo change from this patch.

> 
>  static int uvc_ioctl_s_try_ext_ctrls(struct uvc_fh *handle,

-- 
Regards,

Laurent Pinchart

^ permalink raw reply	[flat|nested] 10+ messages in thread

* Re: [PATCH v2] [media] Use common error handling code in 20 functions
  2018-02-19 18:11 [PATCH v2] [media] Use common error handling code in 20 functions SF Markus Elfring
  2018-02-19 18:37 ` Laurent Pinchart
@ 2018-02-20  8:07 ` Todor Tomov
  2018-03-09 20:10 ` [PATCH v3] [media] Use common error handling code in 19 functions SF Markus Elfring
  2 siblings, 0 replies; 10+ messages in thread
From: Todor Tomov @ 2018-02-20  8:07 UTC (permalink / raw)
  To: SF Markus Elfring, Sean Young, Seung-Woo Kim, Shyam Saini,
	Thomas Gleixner, Wei Yongjun
  Cc: linux-media, Al Viro, Andi Shyti, Andrew Morton, Andrey Utkin,
	Arvind Yadav, Bhumika Goyal, Bjorn Helgaas, Brian Johnson,
	Christoph Böhmwalder, Christophe Jaillet, Colin Ian King,
	Daniele Nicolodi, David Härdeman, Devendra Sharma,
	Gustavo A. R. Silva, Hans Verkuil, Inki Dae, Joe Perches,
	Kees Cook, Laurent Pinchart, Masahiro Yamada,
	Mauro Carvalho Chehab, Max Kellermann, Mike Isely,
	Philippe Ombredanne, Sakari Ailus, Santosh Kumar Singh,
	Satendra Singh Thakur, LKML, kernel-janitors

Hi Markus,

Thank you for the patch.

On 19.02.2018 20:11, SF Markus Elfring wrote:
> From: Markus Elfring <elfring@users.sourceforge.net>
> Date: Mon, 19 Feb 2018 18:50:40 +0100
> 
> Adjust jump targets so that a bit of exception handling can be better
> reused at the end of these functions.
> 
> This issue was partly detected by using the Coccinelle software.
> 
> Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
> ---
> 
> v2:
> Hans Verkuil insisted on patch squashing. Thus several changes
> were recombined based on source files from Linux next-20180216.
> 
> The implementation of the function "tda8261_set_params" was improved
> after a notification by Christoph Böhmwalder on 2017-09-26.
> 
>  drivers/media/dvb-core/dmxdev.c                    | 16 ++++----
>  drivers/media/dvb-frontends/tda1004x.c             | 20 ++++++----
>  drivers/media/dvb-frontends/tda8261.c              | 19 ++++++----
>  drivers/media/pci/bt8xx/dst.c                      | 19 ++++++----
>  drivers/media/pci/bt8xx/dst_ca.c                   | 30 +++++++--------
>  drivers/media/pci/cx88/cx88-input.c                | 17 +++++----
>  drivers/media/platform/omap3isp/ispvideo.c         | 29 +++++++--------
>  .../media/platform/qcom/camss-8x16/camss-csid.c    | 20 +++++-----
>  drivers/media/tuners/tuner-xc2028.c                | 30 +++++++--------
>  drivers/media/usb/cpia2/cpia2_usb.c                | 13 ++++---
>  drivers/media/usb/gspca/gspca.c                    | 17 +++++----
>  drivers/media/usb/gspca/sn9c20x.c                  | 17 +++++----
>  drivers/media/usb/pvrusb2/pvrusb2-ioread.c         | 10 +++--
>  drivers/media/usb/tm6000/tm6000-cards.c            |  7 ++--
>  drivers/media/usb/tm6000/tm6000-dvb.c              | 11 ++++--
>  drivers/media/usb/tm6000/tm6000-video.c            | 13 ++++---
>  drivers/media/usb/ttusb-budget/dvb-ttusb-budget.c  | 13 +++----
>  drivers/media/usb/ttusb-dec/ttusb_dec.c            | 43 ++++++++--------------
>  drivers/media/usb/uvc/uvc_v4l2.c                   | 13 ++++---
>  19 files changed, 180 insertions(+), 177 deletions(-)
> 
> diff --git a/drivers/media/dvb-core/dmxdev.c b/drivers/media/dvb-core/dmxdev.c
> index 6d53af00190e..6a0411c91195 100644

<snip>

> diff --git a/drivers/media/platform/qcom/camss-8x16/camss-csid.c b/drivers/media/platform/qcom/camss-8x16/camss-csid.c
> index 64df82817de3..92d4dc6b4a66 100644
> --- a/drivers/media/platform/qcom/camss-8x16/camss-csid.c
> +++ b/drivers/media/platform/qcom/camss-8x16/camss-csid.c
> @@ -328,16 +328,12 @@ static int csid_set_power(struct v4l2_subdev *sd, int on)
>  			return ret;
>  
>  		ret = csid_set_clock_rates(csid);
> -		if (ret < 0) {
> -			regulator_disable(csid->vdda);
> -			return ret;
> -		}
> +		if (ret < 0)
> +			goto disable_regulator;
>  
>  		ret = camss_enable_clocks(csid->nclocks, csid->clock, dev);
> -		if (ret < 0) {
> -			regulator_disable(csid->vdda);
> -			return ret;
> -		}
> +		if (ret < 0)
> +			goto disable_regulator;
>  
>  		enable_irq(csid->irq);
>  
> @@ -345,8 +341,7 @@ static int csid_set_power(struct v4l2_subdev *sd, int on)
>  		if (ret < 0) {
>  			disable_irq(csid->irq);
>  			camss_disable_clocks(csid->nclocks, csid->clock);
> -			regulator_disable(csid->vdda);
> -			return ret;
> +			goto disable_regulator;
>  		}
>  
>  		hw_version = readl_relaxed(csid->base + CAMSS_CSID_HW_VERSION);
> @@ -357,6 +352,11 @@ static int csid_set_power(struct v4l2_subdev *sd, int on)
>  		ret = regulator_disable(csid->vdda);
>  	}
>  
> +	goto exit;

I think it will be cleaner if you remove the exit label and return here instead.

> +
> +disable_regulator:
> +	regulator_disable(csid->vdda);
> +exit:
>  	return ret;
>  }

-- 
Best regards,
Todor Tomov

^ permalink raw reply	[flat|nested] 10+ messages in thread

* Re: [v2] [media] Use common error handling code in 20 functions
  2018-02-19 18:37 ` Laurent Pinchart
@ 2018-02-28  8:45   ` SF Markus Elfring
  2018-02-28  8:59     ` Laurent Pinchart
  0 siblings, 1 reply; 10+ messages in thread
From: SF Markus Elfring @ 2018-02-28  8:45 UTC (permalink / raw)
  To: Laurent Pinchart, linux-media
  Cc: Al Viro, Andi Shyti, Andrew Morton, Andrey Utkin, Arvind Yadav,
	Bhumika Goyal, Bjorn Helgaas, Brian Johnson,
	Christoph Böhmwalder, Christophe Jaillet, Colin Ian King,
	Daniele Nicolodi, David Härdeman, Devendra Sharma,
	Gustavo A. R. Silva, Hans Verkuil, Inki Dae, Joe Perches,
	Kees Cook, Masahiro Yamada, Mauro Carvalho Chehab,
	Max Kellermann, Mike Isely, Philippe Ombredanne, Sakari Ailus,
	Santosh Kumar Singh, Satendra Singh Thakur, Sean Young,
	Seung-Woo Kim, Shyam Saini, Thomas Gleixner, Todor Tomov,
	Wei Yongjun, LKML, kernel-janitors

>> +put_isp:
>> +	omap3isp_put(video->isp);
>> +delete_fh:
>> +	v4l2_fh_del(&handle->vfh);
>> +	v4l2_fh_exit(&handle->vfh);
>> +	kfree(handle);
> 
> Please prefix the error labels with error_.

How often do you really need such an extra prefix?


>> +++ b/drivers/media/usb/uvc/uvc_v4l2.c
>> @@ -994,10 +994,8 @@ static int uvc_ioctl_g_ext_ctrls(struct file *file,
>> void *fh, struct v4l2_queryctrl qc = { .id = ctrl->id };
>>
>>  			ret = uvc_query_v4l2_ctrl(chain, &qc);
>> -			if (ret < 0) {
>> -				ctrls->error_idx = i;
>> -				return ret;
>> -			}
>> +			if (ret < 0)
>> +				goto set_index;
>>
>>  			ctrl->value = qc.default_value;
>>  		}
>> @@ -1013,14 +1011,17 @@ static int uvc_ioctl_g_ext_ctrls(struct file *file,
>> void *fh, ret = uvc_ctrl_get(chain, ctrl);
>>  		if (ret < 0) {
>>  			uvc_ctrl_rollback(handle);
>> -			ctrls->error_idx = i;
>> -			return ret;
>> +			goto set_index;
>>  		}
>>  	}
>>
>>  	ctrls->error_idx = 0;
>>
>>  	return uvc_ctrl_rollback(handle);
>> +
>> +set_index:
>> +	ctrls->error_idx = i;
>> +	return ret;
>>  }
> 
> For uvcvideo I find this to hinder readability

I got an other development view.


> without adding much added value.

There can be a small effect for such a function implementation.


> Please drop the uvcvideo change from this patch.

Would it be nice if this source code adjustment could be integrated also?

Regards,
Markus

^ permalink raw reply	[flat|nested] 10+ messages in thread

* Re: [v2] [media] Use common error handling code in 20 functions
  2018-02-28  8:45   ` [v2] " SF Markus Elfring
@ 2018-02-28  8:59     ` Laurent Pinchart
  0 siblings, 0 replies; 10+ messages in thread
From: Laurent Pinchart @ 2018-02-28  8:59 UTC (permalink / raw)
  To: SF Markus Elfring
  Cc: linux-media, Al Viro, Andi Shyti, Andrew Morton, Andrey Utkin,
	Arvind Yadav, Bhumika Goyal, Bjorn Helgaas, Brian Johnson,
	Christoph Böhmwalder, Christophe Jaillet, Colin Ian King,
	Daniele Nicolodi, David Härdeman, Devendra Sharma,
	Gustavo A. R. Silva, Hans Verkuil, Inki Dae, Joe Perches,
	Kees Cook, Masahiro Yamada, Mauro Carvalho Chehab,
	Max Kellermann, Mike Isely, Philippe Ombredanne, Sakari Ailus,
	Santosh Kumar Singh, Satendra Singh Thakur, Sean Young,
	Seung-Woo Kim, Shyam Saini, Thomas Gleixner, Todor Tomov,
	Wei Yongjun, LKML, kernel-janitors

Hello,

On Wednesday, 28 February 2018 10:45:21 EET SF Markus Elfring wrote:
> >> +put_isp:
> >> +	omap3isp_put(video->isp);
> >> +delete_fh:
> >> +	v4l2_fh_del(&handle->vfh);
> >> +	v4l2_fh_exit(&handle->vfh);
> >> +	kfree(handle);
> > 
> > Please prefix the error labels with error_.
> 
> How often do you really need such an extra prefix?
> 
> >> +++ b/drivers/media/usb/uvc/uvc_v4l2.c
> >> @@ -994,10 +994,8 @@ static int uvc_ioctl_g_ext_ctrls(struct file *file,
> >> void *fh, struct v4l2_queryctrl qc = { .id = ctrl->id };
> >> 
> >>  			ret = uvc_query_v4l2_ctrl(chain, &qc);
> >> 
> >> -			if (ret < 0) {
> >> -				ctrls->error_idx = i;
> >> -				return ret;
> >> -			}
> >> +			if (ret < 0)
> >> +				goto set_index;
> >> 
> >>  			ctrl->value = qc.default_value;
> >>  		
> >>  		}
> >> 
> >> @@ -1013,14 +1011,17 @@ static int uvc_ioctl_g_ext_ctrls(struct file
> >> *file,
> >> void *fh, ret = uvc_ctrl_get(chain, ctrl);
> >> 
> >>  		if (ret < 0) {
> >>  		
> >>  			uvc_ctrl_rollback(handle);
> >> 
> >> -			ctrls->error_idx = i;
> >> -			return ret;
> >> +			goto set_index;
> >> 
> >>  		}
> >>  	
> >>  	}
> >>  	
> >>  	ctrls->error_idx = 0;
> >>  	
> >>  	return uvc_ctrl_rollback(handle);
> >> 
> >> +
> >> +set_index:
> >> +	ctrls->error_idx = i;
> >> +	return ret;
> >> 
> >>  }
> > 
> > For uvcvideo I find this to hinder readability
> 
> I got an other development view.
> 
> > without adding much added value.
> 
> There can be a small effect for such a function implementation.
> 
> > Please drop the uvcvideo change from this patch.
> 
> Would it be nice if this source code adjustment could be integrated also?

Just for the record, and to avoid merging this patch by mistake,

Nacked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

at least until the requested changes are implemented.

-- 
Regards,

Laurent Pinchart

^ permalink raw reply	[flat|nested] 10+ messages in thread

* [PATCH v3] [media] Use common error handling code in 19 functions
  2018-02-19 18:11 [PATCH v2] [media] Use common error handling code in 20 functions SF Markus Elfring
  2018-02-19 18:37 ` Laurent Pinchart
  2018-02-20  8:07 ` [PATCH v2] " Todor Tomov
@ 2018-03-09 20:10 ` SF Markus Elfring
  2018-03-12  9:30   ` Todor Tomov
  2018-05-04 16:08   ` [v3] " SF Markus Elfring
  2 siblings, 2 replies; 10+ messages in thread
From: SF Markus Elfring @ 2018-03-09 20:10 UTC (permalink / raw)
  To: linux-media, Al Viro, Andi Shyti, Andrew Morton, Andrey Utkin,
	Arvind Yadav, Bhumika Goyal, Bjorn Helgaas, Brian Johnson,
	Christoph Böhmwalder, Christophe Jaillet, Colin Ian King,
	Daniele Nicolodi, David Härdeman, Devendra Sharma,
	Gustavo A. R. Silva, Hans Verkuil, Inki Dae, Joe Perches,
	Kees Cook, Laurent Pinchart, Masahiro Yamada,
	Mauro Carvalho Chehab, Max Kellermann, Mike Isely,
	Philippe Ombredanne, Sakari Ailus, Santosh Kumar Singh,
	Satendra Singh Thakur, Sean Young, Seung-Woo Kim, Shyam Saini,
	Thomas Gleixner, Todor Tomov, Wei Yongjun
  Cc: LKML, kernel-janitors

From: Markus Elfring <elfring@users.sourceforge.net>
Date: Fri, 9 Mar 2018 21:00:12 +0100

Adjust jump targets so that a bit of exception handling can be better
reused at the end of these functions.

This issue was partly detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
---

v3:
Laurent Pinchart and Todor Tomov requested a few adjustments.
Updates were rebased on source files from Linux next-20180308.

v2:
Hans Verkuil insisted on patch squashing. Thus several changes
were recombined based on source files from Linux next-20180216.

The implementation of the function "tda8261_set_params" was improved
after a notification by Christoph Böhmwalder on 2017-09-26.

 drivers/media/dvb-core/dmxdev.c                    | 16 ++++----
 drivers/media/dvb-frontends/tda1004x.c             | 20 ++++++----
 drivers/media/dvb-frontends/tda8261.c              | 19 ++++++----
 drivers/media/pci/bt8xx/dst.c                      | 19 ++++++----
 drivers/media/pci/bt8xx/dst_ca.c                   | 30 +++++++--------
 drivers/media/pci/cx88/cx88-input.c                | 17 +++++----
 drivers/media/platform/omap3isp/ispvideo.c         | 28 ++++++--------
 .../media/platform/qcom/camss-8x16/camss-csid.c    | 19 +++++-----
 drivers/media/tuners/tuner-xc2028.c                | 30 +++++++--------
 drivers/media/usb/cpia2/cpia2_usb.c                | 13 ++++---
 drivers/media/usb/gspca/gspca.c                    | 17 +++++----
 drivers/media/usb/gspca/sn9c20x.c                  | 17 +++++----
 drivers/media/usb/pvrusb2/pvrusb2-ioread.c         | 10 +++--
 drivers/media/usb/tm6000/tm6000-cards.c            |  7 ++--
 drivers/media/usb/tm6000/tm6000-dvb.c              | 11 ++++--
 drivers/media/usb/tm6000/tm6000-video.c            | 13 ++++---
 drivers/media/usb/ttusb-budget/dvb-ttusb-budget.c  | 13 +++----
 drivers/media/usb/ttusb-dec/ttusb_dec.c            | 43 ++++++++--------------
 18 files changed, 171 insertions(+), 171 deletions(-)

diff --git a/drivers/media/dvb-core/dmxdev.c b/drivers/media/dvb-core/dmxdev.c
index 61a750fae465..17d05b05fa9d 100644
--- a/drivers/media/dvb-core/dmxdev.c
+++ b/drivers/media/dvb-core/dmxdev.c
@@ -656,18 +656,18 @@ static int dvb_dmxdev_start_feed(struct dmxdev *dmxdev,
 	tsfeed->priv = filter;
 
 	ret = tsfeed->set(tsfeed, feed->pid, ts_type, ts_pes, timeout);
-	if (ret < 0) {
-		dmxdev->demux->release_ts_feed(dmxdev->demux, tsfeed);
-		return ret;
-	}
+	if (ret < 0)
+		goto release_feed;
 
 	ret = tsfeed->start_filtering(tsfeed);
-	if (ret < 0) {
-		dmxdev->demux->release_ts_feed(dmxdev->demux, tsfeed);
-		return ret;
-	}
+	if (ret < 0)
+		goto release_feed;
 
 	return 0;
+
+release_feed:
+	dmxdev->demux->release_ts_feed(dmxdev->demux, tsfeed);
+	return ret;
 }
 
 static int dvb_dmxdev_filter_start(struct dmxdev_filter *filter)
diff --git a/drivers/media/dvb-frontends/tda1004x.c b/drivers/media/dvb-frontends/tda1004x.c
index 58e3beff5adc..85ca111fc8c4 100644
--- a/drivers/media/dvb-frontends/tda1004x.c
+++ b/drivers/media/dvb-frontends/tda1004x.c
@@ -1299,20 +1299,22 @@ struct dvb_frontend* tda10045_attach(const struct tda1004x_config* config,
 	id = tda1004x_read_byte(state, TDA1004X_CHIPID);
 	if (id < 0) {
 		printk(KERN_ERR "tda10045: chip is not answering. Giving up.\n");
-		kfree(state);
-		return NULL;
+		goto free_state;
 	}
 
 	if (id != 0x25) {
 		printk(KERN_ERR "Invalid tda1004x ID = 0x%02x. Can't proceed\n", id);
-		kfree(state);
-		return NULL;
+		goto free_state;
 	}
 
 	/* create dvb_frontend */
 	memcpy(&state->frontend.ops, &tda10045_ops, sizeof(struct dvb_frontend_ops));
 	state->frontend.demodulator_priv = state;
 	return &state->frontend;
+
+free_state:
+	kfree(state);
+	return NULL;
 }
 
 static const struct dvb_frontend_ops tda10046_ops = {
@@ -1369,19 +1371,21 @@ struct dvb_frontend* tda10046_attach(const struct tda1004x_config* config,
 	id = tda1004x_read_byte(state, TDA1004X_CHIPID);
 	if (id < 0) {
 		printk(KERN_ERR "tda10046: chip is not answering. Giving up.\n");
-		kfree(state);
-		return NULL;
+		goto free_state;
 	}
 	if (id != 0x46) {
 		printk(KERN_ERR "Invalid tda1004x ID = 0x%02x. Can't proceed\n", id);
-		kfree(state);
-		return NULL;
+		goto free_state;
 	}
 
 	/* create dvb_frontend */
 	memcpy(&state->frontend.ops, &tda10046_ops, sizeof(struct dvb_frontend_ops));
 	state->frontend.demodulator_priv = state;
 	return &state->frontend;
+
+free_state:
+	kfree(state);
+	return NULL;
 }
 
 module_param(debug, int, 0644);
diff --git a/drivers/media/dvb-frontends/tda8261.c b/drivers/media/dvb-frontends/tda8261.c
index f72a54e7eb23..7b9a29939b74 100644
--- a/drivers/media/dvb-frontends/tda8261.c
+++ b/drivers/media/dvb-frontends/tda8261.c
@@ -129,18 +129,17 @@ static int tda8261_set_params(struct dvb_frontend *fe)
 
 	/* Set params */
 	err = tda8261_write(state, buf);
-	if (err < 0) {
-		pr_err("%s: I/O Error\n", __func__);
-		return err;
-	}
+	if (err < 0)
+		goto report_failure;
+
 	/* sleep for some time */
 	pr_debug("%s: Waiting to Phase LOCK\n", __func__);
 	msleep(20);
 	/* check status */
-	if ((err = tda8261_get_status(fe, &status)) < 0) {
-		pr_err("%s: I/O Error\n", __func__);
-		return err;
-	}
+	err = tda8261_get_status(fe, &status);
+	if (err < 0)
+		goto report_failure;
+
 	if (status == 1) {
 		pr_debug("%s: Tuner Phase locked: status=%d\n", __func__,
 			 status);
@@ -150,6 +149,10 @@ static int tda8261_set_params(struct dvb_frontend *fe)
 	}
 
 	return 0;
+
+report_failure:
+	pr_err("%s: I/O Error\n", __func__);
+	return err;
 }
 
 static void tda8261_release(struct dvb_frontend *fe)
diff --git a/drivers/media/pci/bt8xx/dst.c b/drivers/media/pci/bt8xx/dst.c
index 4f0bba9e4c48..7014cb6a0ad6 100644
--- a/drivers/media/pci/bt8xx/dst.c
+++ b/drivers/media/pci/bt8xx/dst.c
@@ -134,17 +134,20 @@ EXPORT_SYMBOL(rdc_reset_state);
 static int rdc_8820_reset(struct dst_state *state)
 {
 	dprintk(3, "Resetting DST\n");
-	if (dst_gpio_outb(state, RDC_8820_RESET, RDC_8820_RESET, 0, NO_DELAY) < 0) {
-		pr_err("dst_gpio_outb ERROR !\n");
-		return -1;
-	}
+	if (dst_gpio_outb(state, RDC_8820_RESET, RDC_8820_RESET, 0, NO_DELAY)
+	    < 0)
+		goto report_failure;
+
 	udelay(1000);
-	if (dst_gpio_outb(state, RDC_8820_RESET, RDC_8820_RESET, RDC_8820_RESET, DELAY) < 0) {
-		pr_err("dst_gpio_outb ERROR !\n");
-		return -1;
-	}
+	if (dst_gpio_outb(state, RDC_8820_RESET, RDC_8820_RESET,
+			  RDC_8820_RESET, DELAY) < 0)
+		goto report_failure;
 
 	return 0;
+
+report_failure:
+	pr_err("dst_gpio_outb ERROR !\n");
+	return -1;
 }
 
 static int dst_pio_enable(struct dst_state *state)
diff --git a/drivers/media/pci/bt8xx/dst_ca.c b/drivers/media/pci/bt8xx/dst_ca.c
index 0a7623c0fc8e..26e05a8457e6 100644
--- a/drivers/media/pci/bt8xx/dst_ca.c
+++ b/drivers/media/pci/bt8xx/dst_ca.c
@@ -83,33 +83,33 @@ static int dst_ci_command(struct dst_state* state, u8 * data, u8 *ca_string, u8
 
 	if (write_dst(state, data, len)) {
 		dprintk(verbose, DST_CA_INFO, 1, " Write not successful, trying to recover");
-		dst_error_recovery(state);
-		goto error;
+		goto error_recovery;
 	}
 	if ((dst_pio_disable(state)) < 0) {
 		dprintk(verbose, DST_CA_ERROR, 1, " DST PIO disable failed.");
-		goto error;
-	}
-	if (read_dst(state, &reply, GET_ACK) < 0) {
-		dprintk(verbose, DST_CA_INFO, 1, " Read not successful, trying to recover");
-		dst_error_recovery(state);
-		goto error;
+		goto unlock;
 	}
+	if (read_dst(state, &reply, GET_ACK) < 0)
+		goto report_read_failure;
+
 	if (read) {
 		if (! dst_wait_dst_ready(state, LONG_DELAY)) {
 			dprintk(verbose, DST_CA_NOTICE, 1, " 8820 not ready");
-			goto error;
-		}
-		if (read_dst(state, ca_string, 128) < 0) {	/*	Try to make this dynamic	*/
-			dprintk(verbose, DST_CA_INFO, 1, " Read not successful, trying to recover");
-			dst_error_recovery(state);
-			goto error;
+			goto unlock;
 		}
+		/* Try to make this dynamic */
+		if (read_dst(state, ca_string, 128) < 0)
+			goto report_read_failure;
 	}
 	mutex_unlock(&state->dst_mutex);
 	return 0;
 
-error:
+report_read_failure:
+	dprintk(verbose, DST_CA_INFO, 1,
+		" Read not successful, trying to recover");
+error_recovery:
+	dst_error_recovery(state);
+unlock:
 	mutex_unlock(&state->dst_mutex);
 	return -EIO;
 }
diff --git a/drivers/media/pci/cx88/cx88-input.c b/drivers/media/pci/cx88/cx88-input.c
index 6f4e6923a91a..9df9a8506c1f 100644
--- a/drivers/media/pci/cx88/cx88-input.c
+++ b/drivers/media/pci/cx88/cx88-input.c
@@ -566,20 +566,17 @@ static int get_key_pvr2000(struct IR_i2c *ir, enum rc_proto *protocol,
 
 	/* poll IR chip */
 	flags = i2c_smbus_read_byte_data(ir->c, 0x10);
-	if (flags < 0) {
-		dprintk("read error\n");
-		return 0;
-	}
+	if (flags < 0)
+		goto report_read_failure;
+
 	/* key pressed ? */
 	if (0 == (flags & 0x80))
 		return 0;
 
 	/* read actual key code */
 	code = i2c_smbus_read_byte_data(ir->c, 0x00);
-	if (code < 0) {
-		dprintk("read error\n");
-		return 0;
-	}
+	if (code < 0)
+		goto report_read_failure;
 
 	dprintk("IR Key/Flags: (0x%02x/0x%02x)\n",
 		code & 0xff, flags & 0xff);
@@ -588,6 +585,10 @@ static int get_key_pvr2000(struct IR_i2c *ir, enum rc_proto *protocol,
 	*scancode = code & 0xff;
 	*toggle = 0;
 	return 1;
+
+report_read_failure:
+	dprintk("read error\n");
+	return 0;
 }
 
 void cx88_i2c_init_ir(struct cx88_core *core)
diff --git a/drivers/media/platform/omap3isp/ispvideo.c b/drivers/media/platform/omap3isp/ispvideo.c
index a751c89a3ea8..038b8c5d058b 100644
--- a/drivers/media/platform/omap3isp/ispvideo.c
+++ b/drivers/media/platform/omap3isp/ispvideo.c
@@ -1315,14 +1315,12 @@ static int isp_video_open(struct file *file)
 	/* If this is the first user, initialise the pipeline. */
 	if (omap3isp_get(video->isp) == NULL) {
 		ret = -EBUSY;
-		goto done;
+		goto error_delete_fh;
 	}
 
 	ret = v4l2_pipeline_pm_use(&video->video.entity, 1);
-	if (ret < 0) {
-		omap3isp_put(video->isp);
-		goto done;
-	}
+	if (ret < 0)
+		goto error_put_isp;
 
 	queue = &handle->queue;
 	queue->type = video->type;
@@ -1335,10 +1333,8 @@ static int isp_video_open(struct file *file)
 	queue->dev = video->isp->dev;
 
 	ret = vb2_queue_init(&handle->queue);
-	if (ret < 0) {
-		omap3isp_put(video->isp);
-		goto done;
-	}
+	if (ret < 0)
+		goto error_put_isp;
 
 	memset(&handle->format, 0, sizeof(handle->format));
 	handle->format.type = video->type;
@@ -1346,14 +1342,14 @@ static int isp_video_open(struct file *file)
 
 	handle->video = video;
 	file->private_data = &handle->vfh;
+	return 0;
 
-done:
-	if (ret < 0) {
-		v4l2_fh_del(&handle->vfh);
-		v4l2_fh_exit(&handle->vfh);
-		kfree(handle);
-	}
-
+error_put_isp:
+	omap3isp_put(video->isp);
+error_delete_fh:
+	v4l2_fh_del(&handle->vfh);
+	v4l2_fh_exit(&handle->vfh);
+	kfree(handle);
 	return ret;
 }
 
diff --git a/drivers/media/platform/qcom/camss-8x16/camss-csid.c b/drivers/media/platform/qcom/camss-8x16/camss-csid.c
index 64df82817de3..5c790d8c1f80 100644
--- a/drivers/media/platform/qcom/camss-8x16/camss-csid.c
+++ b/drivers/media/platform/qcom/camss-8x16/camss-csid.c
@@ -328,16 +328,12 @@ static int csid_set_power(struct v4l2_subdev *sd, int on)
 			return ret;
 
 		ret = csid_set_clock_rates(csid);
-		if (ret < 0) {
-			regulator_disable(csid->vdda);
-			return ret;
-		}
+		if (ret < 0)
+			goto disable_regulator;
 
 		ret = camss_enable_clocks(csid->nclocks, csid->clock, dev);
-		if (ret < 0) {
-			regulator_disable(csid->vdda);
-			return ret;
-		}
+		if (ret < 0)
+			goto disable_regulator;
 
 		enable_irq(csid->irq);
 
@@ -345,8 +341,7 @@ static int csid_set_power(struct v4l2_subdev *sd, int on)
 		if (ret < 0) {
 			disable_irq(csid->irq);
 			camss_disable_clocks(csid->nclocks, csid->clock);
-			regulator_disable(csid->vdda);
-			return ret;
+			goto disable_regulator;
 		}
 
 		hw_version = readl_relaxed(csid->base + CAMSS_CSID_HW_VERSION);
@@ -358,6 +353,10 @@ static int csid_set_power(struct v4l2_subdev *sd, int on)
 	}
 
 	return ret;
+
+disable_regulator:
+	regulator_disable(csid->vdda);
+	return ret;
 }
 
 /*
diff --git a/drivers/media/tuners/tuner-xc2028.c b/drivers/media/tuners/tuner-xc2028.c
index fca85e08ebd7..2199b04c0ba9 100644
--- a/drivers/media/tuners/tuner-xc2028.c
+++ b/drivers/media/tuners/tuner-xc2028.c
@@ -571,7 +571,7 @@ static int load_firmware(struct dvb_frontend *fe, unsigned int type,
 		/* Checks if there's enough bytes to read */
 		if (p + sizeof(size) > endp) {
 			tuner_err("Firmware chunk size is wrong\n");
-			return -EINVAL;
+			goto e_inval;
 		}
 
 		size = le16_to_cpu(*(__le16 *) p);
@@ -583,28 +583,23 @@ static int load_firmware(struct dvb_frontend *fe, unsigned int type,
 		if (!size) {
 			/* Special callback command received */
 			rc = do_tuner_callback(fe, XC2028_TUNER_RESET, 0);
-			if (rc < 0) {
-				tuner_err("Error at RESET code %d\n",
-					   (*p) & 0x7f);
-				return -EINVAL;
-			}
+			if (rc < 0)
+				goto report_failure;
+
 			continue;
 		}
 		if (size >= 0xff00) {
 			switch (size) {
 			case 0xff00:
 				rc = do_tuner_callback(fe, XC2028_RESET_CLK, 0);
-				if (rc < 0) {
-					tuner_err("Error at RESET code %d\n",
-						  (*p) & 0x7f);
-					return -EINVAL;
-				}
+				if (rc < 0)
+					goto report_failure;
+
 				break;
 			default:
 				tuner_info("Invalid RESET code %d\n",
 					   size & 0x7f);
-				return -EINVAL;
-
+				goto e_inval;
 			}
 			continue;
 		}
@@ -618,7 +613,7 @@ static int load_firmware(struct dvb_frontend *fe, unsigned int type,
 		if ((size + p > endp)) {
 			tuner_err("missing bytes: need %d, have %d\n",
 				   size, (int)(endp - p));
-			return -EINVAL;
+			goto e_inval;
 		}
 
 		buf[0] = *p;
@@ -635,7 +630,7 @@ static int load_firmware(struct dvb_frontend *fe, unsigned int type,
 			rc = i2c_send(priv, buf, len + 1);
 			if (rc < 0) {
 				tuner_err("%d returned from send\n", rc);
-				return -EINVAL;
+				goto e_inval;
 			}
 
 			p += len;
@@ -650,6 +645,11 @@ static int load_firmware(struct dvb_frontend *fe, unsigned int type,
 		}
 	}
 	return 0;
+
+report_failure:
+	tuner_err("Error at RESET code %d\n", (*p) & 0x7f);
+e_inval:
+	return -EINVAL;
 }
 
 static int load_scode(struct dvb_frontend *fe, unsigned int type,
diff --git a/drivers/media/usb/cpia2/cpia2_usb.c b/drivers/media/usb/cpia2/cpia2_usb.c
index f3a1e5b1e57c..c6eaecbac831 100644
--- a/drivers/media/usb/cpia2/cpia2_usb.c
+++ b/drivers/media/usb/cpia2/cpia2_usb.c
@@ -848,15 +848,13 @@ static int cpia2_usb_probe(struct usb_interface *intf,
 	ret = set_alternate(cam, USBIF_CMDONLY);
 	if (ret < 0) {
 		ERR("%s: usb_set_interface error (ret = %d)\n", __func__, ret);
-		kfree(cam);
-		return ret;
+		goto free_data;
 	}
 
 
 	if((ret = cpia2_init_camera(cam)) < 0) {
 		ERR("%s: failed to initialize cpia2 camera (ret = %d)\n", __func__, ret);
-		kfree(cam);
-		return ret;
+		goto free_data;
 	}
 	LOG("  CPiA Version: %d.%02d (%d.%d)\n",
 	       cam->params.version.firmware_revision_hi,
@@ -876,11 +874,14 @@ static int cpia2_usb_probe(struct usb_interface *intf,
 	ret = cpia2_register_camera(cam);
 	if (ret < 0) {
 		ERR("%s: Failed to register cpia2 camera (ret = %d)\n", __func__, ret);
-		kfree(cam);
-		return ret;
+		goto free_data;
 	}
 
 	return 0;
+
+free_data:
+	kfree(cam);
+	return ret;
 }
 
 /******************************************************************************
diff --git a/drivers/media/usb/gspca/gspca.c b/drivers/media/usb/gspca/gspca.c
index d29773b8f696..7ca44e109a69 100644
--- a/drivers/media/usb/gspca/gspca.c
+++ b/drivers/media/usb/gspca/gspca.c
@@ -907,10 +907,8 @@ static int gspca_init_transfer(struct gspca_dev *gspca_dev)
 			ret = create_urbs(gspca_dev,
 				alt_xfer(&intf->altsetting[alt], xfer,
 					 gspca_dev->xfer_ep));
-			if (ret < 0) {
-				destroy_urbs(gspca_dev);
-				goto out;
-			}
+			if (ret < 0)
+				goto destroy_urbs;
 		}
 
 		/* clear the bulk endpoint */
@@ -920,10 +918,9 @@ static int gspca_init_transfer(struct gspca_dev *gspca_dev)
 
 		/* start the cam */
 		ret = gspca_dev->sd_desc->start(gspca_dev);
-		if (ret < 0) {
-			destroy_urbs(gspca_dev);
-			goto out;
-		}
+		if (ret < 0)
+			goto destroy_urbs;
+
 		gspca_dev->streaming = 1;
 		v4l2_ctrl_handler_setup(gspca_dev->vdev.ctrl_handler);
 
@@ -974,6 +971,10 @@ static int gspca_init_transfer(struct gspca_dev *gspca_dev)
 out:
 	gspca_input_create_urb(gspca_dev);
 	return ret;
+
+destroy_urbs:
+	destroy_urbs(gspca_dev);
+	goto out;
 }
 
 static void gspca_set_default_mode(struct gspca_dev *gspca_dev)
diff --git a/drivers/media/usb/gspca/sn9c20x.c b/drivers/media/usb/gspca/sn9c20x.c
index cfa2a04d9f3f..06ec3a3253e1 100644
--- a/drivers/media/usb/gspca/sn9c20x.c
+++ b/drivers/media/usb/gspca/sn9c20x.c
@@ -1788,10 +1788,8 @@ static int sd_init(struct gspca_dev *gspca_dev)
 	for (i = 0; i < ARRAY_SIZE(bridge_init); i++) {
 		value = bridge_init[i][1];
 		reg_w(gspca_dev, bridge_init[i][0], &value, 1);
-		if (gspca_dev->usb_err < 0) {
-			pr_err("Device initialization failed\n");
-			return gspca_dev->usb_err;
-		}
+		if (gspca_dev->usb_err < 0)
+			goto report_failure;
 	}
 
 	if (sd->flags & LED_REVERSE)
@@ -1800,10 +1798,8 @@ static int sd_init(struct gspca_dev *gspca_dev)
 		reg_w1(gspca_dev, 0x1006, 0x20);
 
 	reg_w(gspca_dev, 0x10c0, i2c_init, 9);
-	if (gspca_dev->usb_err < 0) {
-		pr_err("Device initialization failed\n");
-		return gspca_dev->usb_err;
-	}
+	if (gspca_dev->usb_err < 0)
+		goto report_failure;
 
 	switch (sd->sensor) {
 	case SENSOR_OV9650:
@@ -1869,6 +1865,11 @@ static int sd_init(struct gspca_dev *gspca_dev)
 		pr_err("Unsupported sensor\n");
 		gspca_dev->usb_err = -ENODEV;
 	}
+	goto exit;
+
+report_failure:
+	pr_err("Device initialization failed\n");
+exit:
 	return gspca_dev->usb_err;
 }
 
diff --git a/drivers/media/usb/pvrusb2/pvrusb2-ioread.c b/drivers/media/usb/pvrusb2/pvrusb2-ioread.c
index 602097bdcf14..0218614ce988 100644
--- a/drivers/media/usb/pvrusb2/pvrusb2-ioread.c
+++ b/drivers/media/usb/pvrusb2/pvrusb2-ioread.c
@@ -266,8 +266,7 @@ static int pvr2_ioread_get_buffer(struct pvr2_ioread *cp)
 				pvr2_trace(PVR2_TRACE_DATA_FLOW,
 					   "/*---TRACE_READ---*/ pvr2_ioread_read id=%p queue_error=%d",
 					   cp,stat);
-				pvr2_ioread_stop(cp);
-				return 0;
+				goto stop_read;
 			}
 			cp->c_buf = NULL;
 			cp->c_data_ptr = NULL;
@@ -286,9 +285,8 @@ static int pvr2_ioread_get_buffer(struct pvr2_ioread *cp)
 				pvr2_trace(PVR2_TRACE_DATA_FLOW,
 					   "/*---TRACE_READ---*/ pvr2_ioread_read id=%p buffer_error=%d",
 					   cp,stat);
-				pvr2_ioread_stop(cp);
 				// Give up.
-				return 0;
+				goto stop_read;
 			}
 			// Start over...
 			continue;
@@ -298,6 +296,10 @@ static int pvr2_ioread_get_buffer(struct pvr2_ioread *cp)
 			pvr2_buffer_get_id(cp->c_buf)];
 	}
 	return !0;
+
+stop_read:
+	pvr2_ioread_stop(cp);
+	return 0;
 }
 
 static void pvr2_ioread_filter(struct pvr2_ioread *cp)
diff --git a/drivers/media/usb/tm6000/tm6000-cards.c b/drivers/media/usb/tm6000/tm6000-cards.c
index 70939e96b856..9c467fdf4209 100644
--- a/drivers/media/usb/tm6000/tm6000-cards.c
+++ b/drivers/media/usb/tm6000/tm6000-cards.c
@@ -861,15 +861,14 @@ int tm6000_cards_setup(struct tm6000_core *dev)
 		for (i = 0; i < 2; i++) {
 			rc = tm6000_set_reg(dev, REQ_03_SET_GET_MCU_PIN,
 						dev->gpio.tuner_reset, 0x00);
-			if (rc < 0) {
-				printk(KERN_ERR "Error %i doing tuner reset\n", rc);
-				return rc;
-			}
+			if (rc < 0)
+				goto report_failure;
 
 			msleep(10); /* Just to be conservative */
 			rc = tm6000_set_reg(dev, REQ_03_SET_GET_MCU_PIN,
 						dev->gpio.tuner_reset, 0x01);
 			if (rc < 0) {
+report_failure:
 				printk(KERN_ERR "Error %i doing tuner reset\n", rc);
 				return rc;
 			}
diff --git a/drivers/media/usb/tm6000/tm6000-dvb.c b/drivers/media/usb/tm6000/tm6000-dvb.c
index c811fc6cf48a..7cc5c5aa08c2 100644
--- a/drivers/media/usb/tm6000/tm6000-dvb.c
+++ b/drivers/media/usb/tm6000/tm6000-dvb.c
@@ -134,8 +134,8 @@ static int tm6000_start_stream(struct tm6000_core *dev)
 
 	dvb->bulk_urb->transfer_buffer = kzalloc(size, GFP_KERNEL);
 	if (!dvb->bulk_urb->transfer_buffer) {
-		usb_free_urb(dvb->bulk_urb);
-		return -ENOMEM;
+		ret = -ENOMEM;
+		goto free_urb;
 	}
 
 	usb_fill_bulk_urb(dvb->bulk_urb, dev->udev, pipe,
@@ -160,11 +160,14 @@ static int tm6000_start_stream(struct tm6000_core *dev)
 									ret);
 
 		kfree(dvb->bulk_urb->transfer_buffer);
-		usb_free_urb(dvb->bulk_urb);
-		return ret;
+		goto free_urb;
 	}
 
 	return 0;
+
+free_urb:
+	usb_free_urb(dvb->bulk_urb);
+	return ret;
 }
 
 static void tm6000_stop_stream(struct tm6000_core *dev)
diff --git a/drivers/media/usb/tm6000/tm6000-video.c b/drivers/media/usb/tm6000/tm6000-video.c
index 8314d3fa9241..7c1d5e259ea3 100644
--- a/drivers/media/usb/tm6000/tm6000-video.c
+++ b/drivers/media/usb/tm6000/tm6000-video.c
@@ -589,10 +589,8 @@ static int tm6000_prepare_isoc(struct tm6000_core *dev)
 
 	dev->isoc_ctl.transfer_buffer = kmalloc(sizeof(void *)*num_bufs,
 				   GFP_KERNEL);
-	if (!dev->isoc_ctl.transfer_buffer) {
-		kfree(dev->isoc_ctl.urb);
-		return -ENOMEM;
-	}
+	if (!dev->isoc_ctl.transfer_buffer)
+		goto free_urb;
 
 	dprintk(dev, V4L2_DEBUG_QUEUE, "Allocating %d x %d packets (%d bytes) of %d bytes each to handle %u size\n",
 		    max_packets, num_bufs, sb_size,
@@ -604,9 +602,8 @@ static int tm6000_prepare_isoc(struct tm6000_core *dev)
 
 		/* call free, as some buffers might have been allocated */
 		tm6000_free_urb_buffers(dev);
-		kfree(dev->isoc_ctl.urb);
 		kfree(dev->isoc_ctl.transfer_buffer);
-		return -ENOMEM;
+		goto free_urb;
 	}
 
 	/* allocate urbs and transfer buffers */
@@ -636,6 +633,10 @@ static int tm6000_prepare_isoc(struct tm6000_core *dev)
 	}
 
 	return 0;
+
+free_urb:
+	kfree(dev->isoc_ctl.urb);
+	return -ENOMEM;
 }
 
 static int tm6000_start_thread(struct tm6000_core *dev)
diff --git a/drivers/media/usb/ttusb-budget/dvb-ttusb-budget.c b/drivers/media/usb/ttusb-budget/dvb-ttusb-budget.c
index eed56895c2b9..b093a843644b 100644
--- a/drivers/media/usb/ttusb-budget/dvb-ttusb-budget.c
+++ b/drivers/media/usb/ttusb-budget/dvb-ttusb-budget.c
@@ -1665,8 +1665,7 @@ static int ttusb_probe(struct usb_interface *intf, const struct usb_device_id *i
 	if (result < 0) {
 		dprintk("%s: ttusb_alloc_iso_urbs - failed\n", __func__);
 		mutex_unlock(&ttusb->semi2c);
-		kfree(ttusb);
-		return result;
+		goto err_free_usb;
 	}
 
 	if (ttusb_init_controller(ttusb))
@@ -1677,11 +1676,9 @@ static int ttusb_probe(struct usb_interface *intf, const struct usb_device_id *i
 	result = dvb_register_adapter(&ttusb->adapter,
 				      "Technotrend/Hauppauge Nova-USB",
 				      THIS_MODULE, &udev->dev, adapter_nr);
-	if (result < 0) {
-		ttusb_free_iso_urbs(ttusb);
-		kfree(ttusb);
-		return result;
-	}
+	if (result < 0)
+		goto err_free_iso_urbs;
+
 	ttusb->adapter.priv = ttusb;
 
 	/* i2c */
@@ -1752,7 +1749,9 @@ static int ttusb_probe(struct usb_interface *intf, const struct usb_device_id *i
 	i2c_del_adapter(&ttusb->i2c_adap);
 err_unregister_adapter:
 	dvb_unregister_adapter (&ttusb->adapter);
+err_free_iso_urbs:
 	ttusb_free_iso_urbs(ttusb);
+err_free_usb:
 	kfree(ttusb);
 	return result;
 }
diff --git a/drivers/media/usb/ttusb-dec/ttusb_dec.c b/drivers/media/usb/ttusb-dec/ttusb_dec.c
index 44ca66cb9b8f..d3ba5fb47c6f 100644
--- a/drivers/media/usb/ttusb-dec/ttusb_dec.c
+++ b/drivers/media/usb/ttusb-dec/ttusb_dec.c
@@ -1498,10 +1498,7 @@ static int ttusb_dec_init_dvb(struct ttusb_dec *dec)
 	if ((result = dvb_dmx_init(&dec->demux)) < 0) {
 		printk("%s: dvb_dmx_init failed: error %d\n", __func__,
 		       result);
-
-		dvb_unregister_adapter(&dec->adapter);
-
-		return result;
+		goto unregister_adapter;
 	}
 
 	dec->dmxdev.filternum = 32;
@@ -1511,43 +1508,33 @@ static int ttusb_dec_init_dvb(struct ttusb_dec *dec)
 	if ((result = dvb_dmxdev_init(&dec->dmxdev, &dec->adapter)) < 0) {
 		printk("%s: dvb_dmxdev_init failed: error %d\n",
 		       __func__, result);
-
-		dvb_dmx_release(&dec->demux);
-		dvb_unregister_adapter(&dec->adapter);
-
-		return result;
+		goto release_demux;
 	}
 
 	dec->frontend.source = DMX_FRONTEND_0;
 
-	if ((result = dec->demux.dmx.add_frontend(&dec->demux.dmx,
-						  &dec->frontend)) < 0) {
-		printk("%s: dvb_dmx_init failed: error %d\n", __func__,
-		       result);
-
-		dvb_dmxdev_release(&dec->dmxdev);
-		dvb_dmx_release(&dec->demux);
-		dvb_unregister_adapter(&dec->adapter);
-
-		return result;
-	}
+	result = dec->demux.dmx.add_frontend(&dec->demux.dmx, &dec->frontend);
+	if (result < 0)
+		goto report_failure;
 
 	if ((result = dec->demux.dmx.connect_frontend(&dec->demux.dmx,
 						      &dec->frontend)) < 0) {
-		printk("%s: dvb_dmx_init failed: error %d\n", __func__,
-		       result);
-
 		dec->demux.dmx.remove_frontend(&dec->demux.dmx, &dec->frontend);
-		dvb_dmxdev_release(&dec->dmxdev);
-		dvb_dmx_release(&dec->demux);
-		dvb_unregister_adapter(&dec->adapter);
-
-		return result;
+		goto report_failure;
 	}
 
 	dvb_net_init(&dec->adapter, &dec->dvb_net, &dec->demux.dmx);
 
 	return 0;
+
+report_failure:
+	printk("%s: dvb_dmx_init failed: error %d\n", __func__, result);
+	dvb_dmxdev_release(&dec->dmxdev);
+release_demux:
+	dvb_dmx_release(&dec->demux);
+unregister_adapter:
+	dvb_unregister_adapter(&dec->adapter);
+	return result;
 }
 
 static void ttusb_dec_exit_dvb(struct ttusb_dec *dec)
-- 
2.16.2

^ permalink raw reply	[flat|nested] 10+ messages in thread

* Re: [PATCH v3] [media] Use common error handling code in 19 functions
  2018-03-09 20:10 ` [PATCH v3] [media] Use common error handling code in 19 functions SF Markus Elfring
@ 2018-03-12  9:30   ` Todor Tomov
  2018-05-04 16:08   ` [v3] " SF Markus Elfring
  1 sibling, 0 replies; 10+ messages in thread
From: Todor Tomov @ 2018-03-12  9:30 UTC (permalink / raw)
  To: SF Markus Elfring, Sean Young, Seung-Woo Kim, Shyam Saini,
	Thomas Gleixner, Wei Yongjun
  Cc: linux-media, Al Viro, Andi Shyti, Andrew Morton, Andrey Utkin,
	Arvind Yadav, Bhumika Goyal, Bjorn Helgaas, Brian Johnson,
	Christoph Böhmwalder, Christophe Jaillet, Colin Ian King,
	Daniele Nicolodi, David Härdeman, Devendra Sharma,
	Gustavo A. R. Silva, Hans Verkuil, Inki Dae, Joe Perches,
	Kees Cook, Laurent Pinchart, Masahiro Yamada,
	Mauro Carvalho Chehab, Max Kellermann, Mike Isely,
	Philippe Ombredanne, Sakari Ailus, Santosh Kumar Singh,
	Satendra Singh Thakur, LKML, kernel-janitors

Hi Markus,

Thank you for the patch.

On  9.03.2018 22:10, SF Markus Elfring wrote:
> From: Markus Elfring <elfring@users.sourceforge.net>
> Date: Fri, 9 Mar 2018 21:00:12 +0100
> 
> Adjust jump targets so that a bit of exception handling can be better
> reused at the end of these functions.
> 
> This issue was partly detected by using the Coccinelle software.
> 
> Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
> ---
> 
> v3:
> Laurent Pinchart and Todor Tomov requested a few adjustments.
> Updates were rebased on source files from Linux next-20180308.
> 
> v2:
> Hans Verkuil insisted on patch squashing. Thus several changes
> were recombined based on source files from Linux next-20180216.
> 
> The implementation of the function "tda8261_set_params" was improved
> after a notification by Christoph Böhmwalder on 2017-09-26.
> 
>  drivers/media/dvb-core/dmxdev.c                    | 16 ++++----
>  drivers/media/dvb-frontends/tda1004x.c             | 20 ++++++----
>  drivers/media/dvb-frontends/tda8261.c              | 19 ++++++----
>  drivers/media/pci/bt8xx/dst.c                      | 19 ++++++----
>  drivers/media/pci/bt8xx/dst_ca.c                   | 30 +++++++--------
>  drivers/media/pci/cx88/cx88-input.c                | 17 +++++----
>  drivers/media/platform/omap3isp/ispvideo.c         | 28 ++++++--------
>  .../media/platform/qcom/camss-8x16/camss-csid.c    | 19 +++++-----
>  drivers/media/tuners/tuner-xc2028.c                | 30 +++++++--------
>  drivers/media/usb/cpia2/cpia2_usb.c                | 13 ++++---
>  drivers/media/usb/gspca/gspca.c                    | 17 +++++----
>  drivers/media/usb/gspca/sn9c20x.c                  | 17 +++++----
>  drivers/media/usb/pvrusb2/pvrusb2-ioread.c         | 10 +++--
>  drivers/media/usb/tm6000/tm6000-cards.c            |  7 ++--
>  drivers/media/usb/tm6000/tm6000-dvb.c              | 11 ++++--
>  drivers/media/usb/tm6000/tm6000-video.c            | 13 ++++---
>  drivers/media/usb/ttusb-budget/dvb-ttusb-budget.c  | 13 +++----
>  drivers/media/usb/ttusb-dec/ttusb_dec.c            | 43 ++++++++--------------
>  18 files changed, 171 insertions(+), 171 deletions(-)
> 

<snip>

> diff --git a/drivers/media/platform/qcom/camss-8x16/camss-csid.c b/drivers/media/platform/qcom/camss-8x16/camss-csid.c
> index 64df82817de3..5c790d8c1f80 100644
> --- a/drivers/media/platform/qcom/camss-8x16/camss-csid.c
> +++ b/drivers/media/platform/qcom/camss-8x16/camss-csid.c
> @@ -328,16 +328,12 @@ static int csid_set_power(struct v4l2_subdev *sd, int on)
>  			return ret;
>  
>  		ret = csid_set_clock_rates(csid);
> -		if (ret < 0) {
> -			regulator_disable(csid->vdda);
> -			return ret;
> -		}
> +		if (ret < 0)
> +			goto disable_regulator;
>  
>  		ret = camss_enable_clocks(csid->nclocks, csid->clock, dev);
> -		if (ret < 0) {
> -			regulator_disable(csid->vdda);
> -			return ret;
> -		}
> +		if (ret < 0)
> +			goto disable_regulator;
>  
>  		enable_irq(csid->irq);
>  
> @@ -345,8 +341,7 @@ static int csid_set_power(struct v4l2_subdev *sd, int on)
>  		if (ret < 0) {
>  			disable_irq(csid->irq);
>  			camss_disable_clocks(csid->nclocks, csid->clock);
> -			regulator_disable(csid->vdda);
> -			return ret;
> +			goto disable_regulator;
>  		}
>  
>  		hw_version = readl_relaxed(csid->base + CAMSS_CSID_HW_VERSION);
> @@ -358,6 +353,10 @@ static int csid_set_power(struct v4l2_subdev *sd, int on)
>  	}
>  
>  	return ret;
> +
> +disable_regulator:
> +	regulator_disable(csid->vdda);
> +	return ret;
>  }
>  

For the QComm CAMSS part of the patch:
Acked-by: Todor Tomov <todor.tomov@linaro.org>


-- 
Best regards,
Todor Tomov

^ permalink raw reply	[flat|nested] 10+ messages in thread

* Re: [v3] [media] Use common error handling code in 19 functions
  2018-03-09 20:10 ` [PATCH v3] [media] Use common error handling code in 19 functions SF Markus Elfring
  2018-03-12  9:30   ` Todor Tomov
@ 2018-05-04 16:08   ` SF Markus Elfring
  2018-05-04 17:50     ` Mauro Carvalho Chehab
  1 sibling, 1 reply; 10+ messages in thread
From: SF Markus Elfring @ 2018-05-04 16:08 UTC (permalink / raw)
  To: linux-media, Hans Verkuil, Mauro Carvalho Chehab
  Cc: Al Viro, Andi Shyti, Andrew Morton, Andrey Utkin, Arvind Yadav,
	Bhumika Goyal, Bjorn Helgaas, Brian Johnson,
	Christoph Böhmwalder, Christophe Jaillet, Colin Ian King,
	Daniele Nicolodi, David Härdeman, Devendra Sharma,
	Gustavo A. R. Silva, Inki Dae, Joe Perches, Kees Cook,
	Laurent Pinchart, Masahiro Yamada, Max Kellermann, Mike Isely,
	Philippe Ombredanne, Sakari Ailus, Santosh Kumar Singh,
	Satendra Singh Thakur, Sean Young, Seung-Woo Kim, Shyam Saini,
	Thomas Gleixner, Todor Tomov, Wei Yongjun, LKML, kernel-janitors

> Adjust jump targets so that a bit of exception handling can be better
> reused at the end of these functions.

Why was this update suggestion rejected once more a moment ago?

https://patchwork.linuxtv.org/patch/47827/
lkml.kernel.org/r/<57ef3a56-2578-1d5f-1268-348b49b0c573@users.sourceforge.net>
https://lkml.org/lkml/2018/3/9/823

Would you like to integrate such a source code transformation after any further adjustments?

Regards,
Markus

^ permalink raw reply	[flat|nested] 10+ messages in thread

* Re: [v3] [media] Use common error handling code in 19 functions
  2018-05-04 16:08   ` [v3] " SF Markus Elfring
@ 2018-05-04 17:50     ` Mauro Carvalho Chehab
  2018-05-05  7:53       ` SF Markus Elfring
  0 siblings, 1 reply; 10+ messages in thread
From: Mauro Carvalho Chehab @ 2018-05-04 17:50 UTC (permalink / raw)
  To: SF Markus Elfring
  Cc: linux-media, Hans Verkuil, Mauro Carvalho Chehab, Al Viro,
	Andi Shyti, Andrew Morton, Andrey Utkin, Arvind Yadav,
	Bhumika Goyal, Bjorn Helgaas, Brian Johnson,
	Christoph Böhmwalder, Christophe Jaillet, Colin Ian King,
	Daniele Nicolodi, David Härdeman, Devendra Sharma,
	Gustavo A. R. Silva, Inki Dae, Joe Perches, Kees Cook,
	Laurent Pinchart, Masahiro Yamada, Max Kellermann, Mike Isely,
	Philippe Ombredanne, Sakari Ailus, Santosh Kumar Singh,
	Satendra Singh Thakur, Sean Young, Seung-Woo Kim, Shyam Saini,
	Thomas Gleixner, Todor Tomov, Wei Yongjun, LKML, kernel-janitors

Em Fri, 4 May 2018 18:08:59 +0200
SF Markus Elfring <elfring@users.sourceforge.net> escreveu:

> > Adjust jump targets so that a bit of exception handling can be better
> > reused at the end of these functions.  
> 
> Why was this update suggestion rejected once more a moment ago?
> 
> https://patchwork.linuxtv.org/patch/47827/
> lkml.kernel.org/r/<57ef3a56-2578-1d5f-1268-348b49b0c573@users.sourceforge.net>
> https://lkml.org/lkml/2018/3/9/823

Taking just the first diff there as an example:


diff --git a/drivers/media/dvb-core/dmxdev.c b/drivers/media/dvb-core/dmxdev.c
index 61a750fae465..17d05b05fa9d 100644
--- a/drivers/media/dvb-core/dmxdev.c
+++ b/drivers/media/dvb-core/dmxdev.c
@@ -656,18 +656,18 @@  static int dvb_dmxdev_start_feed(struct dmxdev *dmxdev,
 	tsfeed->priv = filter;
 
 	ret = tsfeed->set(tsfeed, feed->pid, ts_type, ts_pes, timeout);
-	if (ret < 0) {
-		dmxdev->demux->release_ts_feed(dmxdev->demux, tsfeed);
-		return ret;
-	}
+	if (ret < 0)
+		goto release_feed;
 
 	ret = tsfeed->start_filtering(tsfeed);
-	if (ret < 0) {
-		dmxdev->demux->release_ts_feed(dmxdev->demux, tsfeed);
-		return ret;
-	}
+	if (ret < 0)
+		goto release_feed;
 
 	return 0;
+
+release_feed:
+	dmxdev->demux->release_ts_feed(dmxdev->demux, tsfeed);
+	return ret;
 }

There's *nothing* wrong with the above. It works fine, avoids goto
and probably even produce the same code, as gcc will likely optimize
it. It is also easier to review, as the error handling is closer
to the code. On the other hand, there's nothing wrong on taking
the approach you're proposing.

In the end, using goto or not on error handling like the above is 
a matter of personal taste - and taste changes with time and with
developer. I really don't have time to keep reviewing patches that
are just churning the code just due to someone's personal taste.

I'm pretty sure if I start accepting things like that, someone
else would be on some future doing patches just reverting it,
and I would be likely having to apply them too.

So, except if the patch is really fixing something - e.g. a broken
error handling code, I'll just ignore such patches and mark as
rejected without further notice/comments from now on.


Thanks,
Mauro

^ permalink raw reply	[flat|nested] 10+ messages in thread

* Re: [v3] [media] Use common error handling code in 19 functions
  2018-05-04 17:50     ` Mauro Carvalho Chehab
@ 2018-05-05  7:53       ` SF Markus Elfring
  0 siblings, 0 replies; 10+ messages in thread
From: SF Markus Elfring @ 2018-05-05  7:53 UTC (permalink / raw)
  To: Mauro Carvalho Chehab, linux-media
  Cc: Hans Verkuil, Mauro Carvalho Chehab, Al Viro, Andrew Morton,
	Andrey Utkin, Arvind Yadav, Bhumika Goyal, Bjorn Helgaas,
	Brian Johnson, Christoph Böhmwalder, Christophe Jaillet,
	Colin Ian King, Daniele Nicolodi, David Härdeman,
	Devendra Sharma, Gustavo A. R. Silva, Inki Dae, Joe Perches,
	Kees Cook, Laurent Pinchart, Masahiro Yamada, Max Kellermann,
	Mike Isely, Philippe Ombredanne, Sakari Ailus,
	Santosh Kumar Singh, Satendra Singh Thakur, Sean Young,
	Seung-Woo Kim, Shyam Saini, Thomas Gleixner, Todor Tomov,
	Wei Yongjun, LKML, kernel-janitors

> @@ -656,18 +656,18 @@  static int dvb_dmxdev_start_feed(struct dmxdev *dmxdev,
>  	tsfeed->priv = filter;
>  
>  	ret = tsfeed->set(tsfeed, feed->pid, ts_type, ts_pes, timeout);
> -	if (ret < 0) {
> -		dmxdev->demux->release_ts_feed(dmxdev->demux, tsfeed);
> -		return ret;
> -	}
> +	if (ret < 0)
> +		goto release_feed;
>  
>  	ret = tsfeed->start_filtering(tsfeed);
> -	if (ret < 0) {
> -		dmxdev->demux->release_ts_feed(dmxdev->demux, tsfeed);
> -		return ret;
> -	}
> +	if (ret < 0)
> +		goto release_feed;
>  
>  	return 0;
> +
> +release_feed:
> +	dmxdev->demux->release_ts_feed(dmxdev->demux, tsfeed);
> +	return ret;
>  }
> 
> There's *nothing* wrong with the above. It works fine,

I can agree to this view in principle according to the required control flow.


> avoids goto

How does this wording fit to information from the section
“7) Centralized exiting of functions” in the document “coding-style.rst”?


> and probably even produce the same code, as gcc will likely optimize it.

Would you like to clarify the current situation around supported
software optimisations any more?


> It is also easier to review, as the error handling is closer
> to the code.

Do we stumble on different coding style preferences once more?


> On the other hand, there's nothing wrong on taking the approach
> you're proposing.

Thanks for another bit of positive feedback.


> In the end, using goto or not on error handling like the above is 
> a matter of personal taste - and taste changes with time

Do Linux guidelines need any adjustments?


> and with developer. I really don't have time to keep reviewing patches
> that are just churning the code just due to someone's personal taste.

I tried to apply another general source code transformation pattern.


> I'm pretty sure if I start accepting things like that,
> someone else would be on some future doing patches just reverting it,
> and I would be likely having to apply them too.

Why?

I hope also that the source code can be kept consistent to some degree.


> So, except if the patch is really fixing something - e.g. a broken
> error handling code, I'll just ignore such patches and mark as
> rejected without further notice/comments from now on.

I would find such a communication style questionable.
Do you distinguish between bug fixes and possible corrections for
other error categories (or software weaknesses)?

Regards,
Markus

^ permalink raw reply	[flat|nested] 10+ messages in thread

end of thread, other threads:[~2018-05-05  7:55 UTC | newest]

Thread overview: 10+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2018-02-19 18:11 [PATCH v2] [media] Use common error handling code in 20 functions SF Markus Elfring
2018-02-19 18:37 ` Laurent Pinchart
2018-02-28  8:45   ` [v2] " SF Markus Elfring
2018-02-28  8:59     ` Laurent Pinchart
2018-02-20  8:07 ` [PATCH v2] " Todor Tomov
2018-03-09 20:10 ` [PATCH v3] [media] Use common error handling code in 19 functions SF Markus Elfring
2018-03-12  9:30   ` Todor Tomov
2018-05-04 16:08   ` [v3] " SF Markus Elfring
2018-05-04 17:50     ` Mauro Carvalho Chehab
2018-05-05  7:53       ` SF Markus Elfring

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