We can't free struct em28xx while one of the extensions is still
using it.
So, add a kref() to control it, freeing it only after the
extensions fini calls.
Signed-off-by: Mauro Carvalho Chehab <m.chehab@xxxxxxxxxxx>
---
v2:
- patch was rebased;
- as em28xx-audio close uses struct em28xx dev, add a kref in order
to track audio open/close.
drivers/media/usb/em28xx/em28xx-audio.c | 8 +++++++-
drivers/media/usb/em28xx/em28xx-cards.c | 34 ++++++++++++++++-----------------
drivers/media/usb/em28xx/em28xx-dvb.c | 5 ++++-
drivers/media/usb/em28xx/em28xx-input.c | 8 +++++++-
drivers/media/usb/em28xx/em28xx-video.c | 14 ++++++++------
drivers/media/usb/em28xx/em28xx.h | 9 +++++++--
6 files changed, 50 insertions(+), 28 deletions(-)
diff --git a/drivers/media/usb/em28xx/em28xx-audio.c b/drivers/media/usb/em28xx/em28xx-audio.c
index 45bea1adc11c..73eeeaf6551f 100644
--- a/drivers/media/usb/em28xx/em28xx-audio.c
+++ b/drivers/media/usb/em28xx/em28xx-audio.c
@@ -265,6 +265,8 @@ static int snd_em28xx_capture_open(struct snd_pcm_substream *substream)
dprintk("opening device and trying to acquire exclusive lock\n");
+ kref_get(&dev->ref);
+
runtime->hw = snd_em28xx_hw_capture;
if ((dev->alt == 0 || dev->audio_ifnum) && dev->adev.users == 0) {
int nonblock = !!(substream->f_flags & O_NONBLOCK);
@@ -330,6 +332,7 @@ static int snd_em28xx_pcm_close(struct snd_pcm_substream *substream)
substream->runtime->dma_area = NULL;
}
mutex_unlock(&dev->lock);
+ kref_put(&dev->ref, em28xx_free_device);
return 0;
}
@@ -886,6 +889,8 @@ static int em28xx_audio_init(struct em28xx *dev)
em28xx_info("Binding audio extension\n");
+ kref_get(&dev->ref);
+
printk(KERN_INFO "em28xx-audio.c: Copyright (C) 2006 Markus "
"Rechberger\n");
printk(KERN_INFO
@@ -958,7 +963,7 @@ static int em28xx_audio_fini(struct em28xx *dev)
if (dev == NULL)
return 0;
- if (dev->has_alsa_audio != 1) {
+ if (!dev->has_alsa_audio) {
/* This device does not support the extension (in this case
the device is expecting the snd-usb-audio module or
doesn't have analog audio support at all) */
@@ -977,6 +982,7 @@ static int em28xx_audio_fini(struct em28xx *dev)
dev->adev.sndcard = NULL;
}
+ kref_put(&dev->ref, em28xx_free_device);
return 0;
}
diff --git a/drivers/media/usb/em28xx/em28xx-cards.c b/drivers/media/usb/em28xx/em28xx-cards.c
index e08d65b2e352..8fc0a437054e 100644
--- a/drivers/media/usb/em28xx/em28xx-cards.c
+++ b/drivers/media/usb/em28xx/em28xx-cards.c
@@ -2867,16 +2867,18 @@ static void flush_request_modules(struct em28xx *dev)
flush_work(&dev->request_module_wk);
}
-/*
- * em28xx_release_resources()
- * unregisters the v4l2,i2c and usb devices
- * called when the device gets disconnected or at module unload
-*/
-void em28xx_release_resources(struct em28xx *dev)
+/**
+ * em28xx_release_resources() - unregisters the v4l2,i2c and usb devices
+ *
+ * @ref: struct kref for em28xx device
+ *
+ * This is called when all extensions and em28xx core unregisters a device
+ */
+void em28xx_free_device(struct kref *ref)
{
- /*FIXME: I2C IR should be disconnected */
+ struct em28xx *dev = kref_to_dev(ref);
- mutex_lock(&dev->lock);
+ em28xx_info("Freeing device\n");
if (dev->def_i2c_bus)
em28xx_i2c_unregister(dev, 1);
@@ -2887,9 +2889,10 @@ void em28xx_release_resources(struct em28xx *dev)
/* Mark device as unused */
clear_bit(dev->devno, &em28xx_devused);
- mutex_unlock(&dev->lock);
-};
-EXPORT_SYMBOL_GPL(em28xx_release_resources);
+ kfree(dev->alt_max_pkt_size_isoc);
+ kfree(dev);
+}
+EXPORT_SYMBOL_GPL(em28xx_free_device);
/*
* em28xx_init_dev()
@@ -3342,6 +3345,8 @@ static int em28xx_usb_probe(struct usb_interface *interface,
dev->dvb_xfer_bulk ? "bulk" : "isoc");
}
+ kref_init(&dev->ref);
+
request_modules(dev);
/* Should be the last thing to do, to avoid newer udev's to
@@ -3385,12 +3390,7 @@ static void em28xx_usb_disconnect(struct usb_interface *interface)
em28xx_close_extension(dev);
- em28xx_release_resources(dev);
-
- if (!dev->users) {
- kfree(dev->alt_max_pkt_size_isoc);
- kfree(dev);
- }
+ kref_put(&dev->ref, em28xx_free_device);
}
static struct usb_driver em28xx_usb_driver = {
diff --git a/drivers/media/usb/em28xx/em28xx-dvb.c b/drivers/media/usb/em28xx/em28xx-dvb.c
index 881a813836eb..7df21e33a923 100644
--- a/drivers/media/usb/em28xx/em28xx-dvb.c
+++ b/drivers/media/usb/em28xx/em28xx-dvb.c
@@ -1005,11 +1005,11 @@ static int em28xx_dvb_init(struct em28xx *dev)
em28xx_info("Binding DVB extension\n");
dvb = kzalloc(sizeof(struct em28xx_dvb), GFP_KERNEL);
-
if (dvb == NULL) {
em28xx_info("em28xx_dvb: memory allocation failed\n");
return -ENOMEM;
}
+ kref_get(&dev->ref);
dev->dvb = dvb;
dvb->fe[0] = dvb->fe[1] = NULL;
@@ -1437,6 +1437,7 @@ static int em28xx_dvb_init(struct em28xx *dev)
dvb->adapter.mfe_shared = mfe_shared;
em28xx_info("DVB extension successfully initialized\n");
+
ret:
em28xx_set_mode(dev, EM28XX_SUSPEND);
mutex_unlock(&dev->lock);
@@ -1489,6 +1490,8 @@ static int em28xx_dvb_fini(struct em28xx *dev)
dev->dvb = NULL;
}
+ kref_put(&dev->ref, em28xx_free_device);
+
return 0;
}
diff --git a/drivers/media/usb/em28xx/em28xx-input.c b/drivers/media/usb/em28xx/em28xx-input.c
index 3d54c04e5230..c98d784a2772 100644
--- a/drivers/media/usb/em28xx/em28xx-input.c
+++ b/drivers/media/usb/em28xx/em28xx-input.c
@@ -675,6 +675,8 @@ static int em28xx_ir_init(struct em28xx *dev)
return 0;
}
+ kref_get(&dev->ref);
+
if (dev->board.buttons)
em28xx_init_buttons(dev);
@@ -817,7 +819,7 @@ static int em28xx_ir_fini(struct em28xx *dev)
/* skip detach on non attached boards */
if (!ir)
- return 0;
+ goto ref_put;
if (ir->rc)
rc_unregister_device(ir->rc);
@@ -825,6 +827,10 @@ static int em28xx_ir_fini(struct em28xx *dev)
/* done */
kfree(ir);
dev->ir = NULL;
+
+ref_put:
+ kref_put(&dev->ref, em28xx_free_device);
+
return 0;
}
diff --git a/drivers/media/usb/em28xx/em28xx-video.c b/drivers/media/usb/em28xx/em28xx-video.c
index aabcafbdab46..f801af8d3f61 100644
--- a/drivers/media/usb/em28xx/em28xx-video.c
+++ b/drivers/media/usb/em28xx/em28xx-video.c
@@ -1837,6 +1837,7 @@ static int em28xx_v4l2_open(struct file *filp)
video_device_node_name(vdev), v4l2_type_names[fh_type],
dev->users);
+ kref_get(&dev->ref);
if (mutex_lock_interruptible(&dev->lock))
return -ERESTARTSYS;
@@ -1926,9 +1927,8 @@ static int em28xx_v4l2_fini(struct em28xx *dev)
v4l2_ctrl_handler_free(&dev->ctrl_handler);
v4l2_device_unregister(&dev->v4l2_dev);
- if (dev->users)
- em28xx_warn("Device is open ! Memory deallocation is deferred on last close.\n");
mutex_unlock(&dev->lock);
+ kref_put(&dev->ref, em28xx_free_device);
return 0;
}
@@ -1950,11 +1950,9 @@ static int em28xx_v4l2_close(struct file *filp)
mutex_lock(&dev->lock);
if (dev->users == 1) {
- /* free the remaining resources if device is disconnected */
- if (dev->disconnected) {
- kfree(dev->alt_max_pkt_size_isoc);
+ /* No sense to try to write to the device */
+ if (dev->disconnected)
goto exit;
- }
/* Save some power by putting tuner to sleep */
v4l2_device_call_all(&dev->v4l2_dev, 0, core, s_power, 0);
@@ -1975,6 +1973,8 @@ static int em28xx_v4l2_close(struct file *filp)
exit:
dev->users--;
mutex_unlock(&dev->lock);
+ kref_put(&dev->ref, em28xx_free_device);
+
return 0;
}
@@ -2206,6 +2206,8 @@ static int em28xx_v4l2_init(struct em28xx *dev)
em28xx_info("Registering V4L2 extension\n");
+ kref_get(&dev->ref);
+
mutex_lock(&dev->lock);
ret = v4l2_device_register(&dev->udev->dev, &dev->v4l2_dev);
diff --git a/drivers/media/usb/em28xx/em28xx.h b/drivers/media/usb/em28xx/em28xx.h
index 10b817245f7e..8b3438891bb3 100644
--- a/drivers/media/usb/em28xx/em28xx.h
+++ b/drivers/media/usb/em28xx/em28xx.h
@@ -32,6 +32,7 @@
#include <linux/workqueue.h>
#include <linux/i2c.h>
#include <linux/mutex.h>
+#include <linux/kref.h>
#include <linux/videodev2.h>
#include <media/videobuf2-vmalloc.h>
@@ -533,9 +534,11 @@ struct em28xx_i2c_bus {
enum em28xx_i2c_algo_type algo_type;
};
-
/* main device struct */
struct em28xx {
+ struct kref ref;
+
+
/* generic device properties */
char name[30]; /* name (including minor) of the device */
int model; /* index in the device_data struct */
@@ -708,6 +711,8 @@ struct em28xx {
struct em28xx_dvb *dvb;
};
+#define kref_to_dev(d) container_of(d, struct em28xx, ref)
+
struct em28xx_ops {
struct list_head next;
char *name;
@@ -765,7 +770,7 @@ extern struct em28xx_board em28xx_boards[];
extern struct usb_device_id em28xx_id_table[];
int em28xx_tuner_callback(void *ptr, int component, int command, int arg);
void em28xx_setup_xc3028(struct em28xx *dev, struct xc2028_ctrl *ctl);
-void em28xx_release_resources(struct em28xx *dev);
+void em28xx_free_device(struct kref *ref);
/* Provided by em28xx-camera.c */
int em28xx_detect_sensor(struct em28xx *dev);
--
1.8.3.1
--
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