8 files changed, 109 insertions, 144 deletions

diff --git a/drivers/staging/most/Kconfig b/drivers/staging/most/Kconfig
index 8948d5246409..6262eb25c80b 100644
--- a/drivers/staging/most/Kconfig
+++ b/drivers/staging/most/Kconfig
@@ -1,9 +1,9 @@
 # SPDX-License-Identifier: GPL-2.0
 menuconfig MOST
-        tristate "MOST support"
+	tristate "MOST support"
 	depends on HAS_DMA && CONFIGFS_FS
-        default n
-        help
+	default n
+	help
 	  Say Y here if you want to enable MOST support.
 	  This driver needs at least one additional component to enable the
 	  desired access from userspace (e.g. character devices) and one that
@@ -12,7 +12,7 @@ menuconfig MOST
 	  To compile this driver as a module, choose M here: the
 	  module will be called most_core.
 
-          If in doubt, say N here.
+	  If in doubt, say N here.
 
 
 
diff --git a/drivers/staging/most/cdev/cdev.c b/drivers/staging/most/cdev/cdev.c
index 724d098aeef0..f880147c82fd 100644
--- a/drivers/staging/most/cdev/cdev.c
+++ b/drivers/staging/most/cdev/cdev.c
@@ -494,6 +494,7 @@ err_remove_ida:
 
 static struct cdev_component comp = {
 	.cc = {
+		.mod = THIS_MODULE,
 		.name = "cdev",
 		.probe_channel = comp_probe,
 		.disconnect_channel = comp_disconnect_channel,
diff --git a/drivers/staging/most/configfs.c b/drivers/staging/most/configfs.c
index 025495657b68..34a9fb53985c 100644
--- a/drivers/staging/most/configfs.c
+++ b/drivers/staging/most/configfs.c
@@ -164,6 +164,7 @@ static ssize_t mdev_link_direction_store(struct config_item *item,
 	    !sysfs_streq(page, "dir_tx") && !sysfs_streq(page, "tx"))
 		return -EINVAL;
 	strcpy(mdev_link->direction, page);
+	strim(mdev_link->direction);
 	return count;
 }
 
@@ -182,6 +183,7 @@ static ssize_t mdev_link_datatype_store(struct config_item *item,
 	    !sysfs_streq(page, "isoc_avp"))
 		return -EINVAL;
 	strcpy(mdev_link->datatype, page);
+	strim(mdev_link->datatype);
 	return count;
 }
 
@@ -196,6 +198,7 @@ static ssize_t mdev_link_device_store(struct config_item *item,
 	struct mdev_link *mdev_link = to_mdev_link(item);
 
 	strcpy(mdev_link->device, page);
+	strim(mdev_link->device);
 	return count;
 }
 
@@ -210,6 +213,7 @@ static ssize_t mdev_link_channel_store(struct config_item *item,
 	struct mdev_link *mdev_link = to_mdev_link(item);
 
 	strcpy(mdev_link->channel, page);
+	strim(mdev_link->channel);
 	return count;
 }
 
@@ -391,22 +395,29 @@ static const struct config_item_type mdev_link_type = {
 
 struct most_common {
 	struct config_group group;
+	struct module *mod;
+	struct configfs_subsystem subsys;
 };
 
-static struct most_common *to_most_common(struct config_item *item)
+static struct most_common *to_most_common(struct configfs_subsystem *subsys)
 {
-	return container_of(to_config_group(item), struct most_common, group);
+	return container_of(subsys, struct most_common, subsys);
 }
 
 static struct config_item *most_common_make_item(struct config_group *group,
 						 const char *name)
 {
 	struct mdev_link *mdev_link;
+	struct most_common *mc = to_most_common(group->cg_subsys);
 
 	mdev_link = kzalloc(sizeof(*mdev_link), GFP_KERNEL);
 	if (!mdev_link)
 		return ERR_PTR(-ENOMEM);
 
+	if (!try_module_get(mc->mod)) {
+		kfree(mdev_link);
+		return ERR_PTR(-ENOLCK);
+	}
 	config_item_init_type_name(&mdev_link->item, name,
 				   &mdev_link_type);
 
@@ -422,15 +433,26 @@ static struct config_item *most_common_make_item(struct config_group *group,
 
 static void most_common_release(struct config_item *item)
 {
-	kfree(to_most_common(item));
+	struct config_group *group = to_config_group(item);
+
+	kfree(to_most_common(group->cg_subsys));
 }
 
 static struct configfs_item_operations most_common_item_ops = {
 	.release	= most_common_release,
 };
 
+static void most_common_disconnect(struct config_group *group,
+				   struct config_item *item)
+{
+	struct most_common *mc = to_most_common(group->cg_subsys);
+
+	module_put(mc->mod);
+}
+
 static struct configfs_group_operations most_common_group_ops = {
 	.make_item	= most_common_make_item,
+	.disconnect_notify = most_common_disconnect,
 };
 
 static const struct config_item_type most_common_type = {
@@ -439,29 +461,35 @@ static const struct config_item_type most_common_type = {
 	.ct_owner	= THIS_MODULE,
 };
 
-static struct configfs_subsystem most_cdev_subsys = {
-	.su_group = {
-		.cg_item = {
-			.ci_namebuf = "most_cdev",
-			.ci_type = &most_common_type,
+static struct most_common most_cdev = {
+	.subsys = {
+		.su_group = {
+			.cg_item = {
+				.ci_namebuf = "most_cdev",
+				.ci_type = &most_common_type,
+			},
 		},
 	},
 };
 
-static struct configfs_subsystem most_net_subsys = {
-	.su_group = {
-		.cg_item = {
-			.ci_namebuf = "most_net",
-			.ci_type = &most_common_type,
+static struct most_common most_net = {
+	.subsys = {
+		.su_group = {
+			.cg_item = {
+				.ci_namebuf = "most_net",
+				.ci_type = &most_common_type,
+			},
 		},
 	},
 };
 
-static struct configfs_subsystem most_video_subsys = {
-	.su_group = {
-		.cg_item = {
-			.ci_namebuf = "most_video",
-			.ci_type = &most_common_type,
+static struct most_common most_video = {
+	.subsys = {
+		.su_group = {
+			.cg_item = {
+				.ci_namebuf = "most_video",
+				.ci_type = &most_common_type,
+			},
 		},
 	},
 };
@@ -487,7 +515,7 @@ static struct config_item *most_snd_grp_make_item(struct config_group *group,
 		return ERR_PTR(-ENOMEM);
 
 	config_item_init_type_name(&mdev_link->item, name, &mdev_link_type);
-	mdev_link->create_link = 0;
+	mdev_link->create_link = false;
 	strcpy(mdev_link->name, name);
 	strcpy(mdev_link->comp, "sound");
 	return &mdev_link->item;
@@ -545,13 +573,14 @@ static const struct config_item_type most_snd_grp_type = {
 struct most_sound {
 	struct configfs_subsystem subsys;
 	struct list_head soundcard_list;
+	struct module *mod;
 };
 
 static struct config_group *most_sound_make_group(struct config_group *group,
 						  const char *name)
 {
 	struct most_snd_grp *most;
-	struct most_sound *ms = container_of(to_configfs_subsystem(group),
+	struct most_sound *ms = container_of(group->cg_subsys,
 					     struct most_sound, subsys);
 
 	list_for_each_entry(most, &ms->soundcard_list, list) {
@@ -560,17 +589,29 @@ static struct config_group *most_sound_make_group(struct config_group *group,
 			return ERR_PTR(-EPROTO);
 		}
 	}
+	if (!try_module_get(ms->mod))
+		return ERR_PTR(-ENOLCK);
 	most = kzalloc(sizeof(*most), GFP_KERNEL);
-	if (!most)
+	if (!most) {
+		module_put(ms->mod);
 		return ERR_PTR(-ENOMEM);
-
+	}
 	config_group_init_type_name(&most->group, name, &most_snd_grp_type);
 	list_add_tail(&most->list, &ms->soundcard_list);
 	return &most->group;
 }
 
+static void most_sound_disconnect(struct config_group *group,
+				  struct config_item *item)
+{
+	struct most_sound *ms = container_of(group->cg_subsys,
+					     struct most_sound, subsys);
+	module_put(ms->mod);
+}
+
 static struct configfs_group_operations most_sound_group_ops = {
 	.make_group	= most_sound_make_group,
+	.disconnect_notify = most_sound_disconnect,
 };
 
 static const struct config_item_type most_sound_type = {
@@ -593,16 +634,21 @@ int most_register_configfs_subsys(struct core_component *c)
 {
 	int ret;
 
-	if (!strcmp(c->name, "cdev"))
-		ret = configfs_register_subsystem(&most_cdev_subsys);
-	else if (!strcmp(c->name, "net"))
-		ret = configfs_register_subsystem(&most_net_subsys);
-	else if (!strcmp(c->name, "video"))
-		ret = configfs_register_subsystem(&most_video_subsys);
-	else if (!strcmp(c->name, "sound"))
+	if (!strcmp(c->name, "cdev")) {
+		most_cdev.mod = c->mod;
+		ret = configfs_register_subsystem(&most_cdev.subsys);
+	} else if (!strcmp(c->name, "net")) {
+		most_net.mod = c->mod;
+		ret = configfs_register_subsystem(&most_net.subsys);
+	} else if (!strcmp(c->name, "video")) {
+		most_video.mod = c->mod;
+		ret = configfs_register_subsystem(&most_video.subsys);
+	} else if (!strcmp(c->name, "sound")) {
+		most_sound_subsys.mod = c->mod;
 		ret = configfs_register_subsystem(&most_sound_subsys.subsys);
-	else
+	} else {
 		return -ENODEV;
+	}
 
 	if (ret) {
 		pr_err("Error %d while registering subsystem %s\n",
@@ -631,11 +677,11 @@ void most_interface_register_notify(const char *mdev)
 void most_deregister_configfs_subsys(struct core_component *c)
 {
 	if (!strcmp(c->name, "cdev"))
-		configfs_unregister_subsystem(&most_cdev_subsys);
+		configfs_unregister_subsystem(&most_cdev.subsys);
 	else if (!strcmp(c->name, "net"))
-		configfs_unregister_subsystem(&most_net_subsys);
+		configfs_unregister_subsystem(&most_net.subsys);
 	else if (!strcmp(c->name, "video"))
-		configfs_unregister_subsystem(&most_video_subsys);
+		configfs_unregister_subsystem(&most_video.subsys);
 	else if (!strcmp(c->name, "sound"))
 		configfs_unregister_subsystem(&most_sound_subsys.subsys);
 }
@@ -643,14 +689,14 @@ EXPORT_SYMBOL_GPL(most_deregister_configfs_subsys);
 
 int __init configfs_init(void)
 {
-	config_group_init(&most_cdev_subsys.su_group);
-	mutex_init(&most_cdev_subsys.su_mutex);
+	config_group_init(&most_cdev.subsys.su_group);
+	mutex_init(&most_cdev.subsys.su_mutex);
 
-	config_group_init(&most_net_subsys.su_group);
-	mutex_init(&most_net_subsys.su_mutex);
+	config_group_init(&most_net.subsys.su_group);
+	mutex_init(&most_net.subsys.su_mutex);
 
-	config_group_init(&most_video_subsys.su_group);
-	mutex_init(&most_video_subsys.su_mutex);
+	config_group_init(&most_video.subsys.su_group);
+	mutex_init(&most_video.subsys.su_mutex);
 
 	config_group_init(&most_sound_subsys.subsys.su_group);
 	mutex_init(&most_sound_subsys.subsys.su_mutex);
diff --git a/drivers/staging/most/core.c b/drivers/staging/most/core.c
index 8e9a0b67c6ed..51a6b41d5b82 100644
--- a/drivers/staging/most/core.c
+++ b/drivers/staging/most/core.c
@@ -52,7 +52,7 @@ struct most_channel {
 	u16 channel_id;
 	char name[STRING_SIZE];
 	bool is_poisoned;
-	struct mutex start_mutex;
+	struct mutex start_mutex; /* channel activation synchronization */
 	struct mutex nq_mutex; /* nq thread synchronization */
 	int is_starving;
 	struct most_interface *iface;
@@ -60,7 +60,7 @@ struct most_channel {
 	bool keep_mbo;
 	bool enqueue_halt;
 	struct list_head fifo;
-	spinlock_t fifo_lock;
+	spinlock_t fifo_lock; /* fifo access synchronization */
 	struct list_head halt_fifo;
 	struct list_head list;
 	struct pipe pipe0;
@@ -84,11 +84,11 @@ static const struct {
 	int most_ch_data_type;
 	const char *name;
 } ch_data_type[] = {
-	{ MOST_CH_CONTROL, "control\n" },
-	{ MOST_CH_ASYNC, "async\n" },
-	{ MOST_CH_SYNC, "sync\n" },
-	{ MOST_CH_ISOC, "isoc\n"},
-	{ MOST_CH_ISOC, "isoc_avp\n"},
+	{ MOST_CH_CONTROL, "control" },
+	{ MOST_CH_ASYNC, "async" },
+	{ MOST_CH_SYNC, "sync" },
+	{ MOST_CH_ISOC, "isoc"},
+	{ MOST_CH_ISOC, "isoc_avp"},
 };
 
 /**
@@ -521,48 +521,6 @@ static ssize_t components_show(struct device_driver *drv, char *buf)
 }
 
 /**
- * split_string - parses buf and extracts ':' separated substrings.
- *
- * @buf: complete string from attribute 'add_channel'
- * @a: storage for 1st substring (=interface name)
- * @b: storage for 2nd substring (=channel name)
- * @c: storage for 3rd substring (=component name)
- * @d: storage optional 4th substring (=user defined name)
- *
- * Examples:
- *
- * Input: "mdev0:ch6:cdev:my_channel\n" or
- *        "mdev0:ch6:cdev:my_channel"
- *
- * Output: *a -> "mdev0", *b -> "ch6", *c -> "cdev" *d -> "my_channel"
- *
- * Input: "mdev1:ep81:cdev\n"
- * Output: *a -> "mdev1", *b -> "ep81", *c -> "cdev" *d -> ""
- *
- * Input: "mdev1:ep81"
- * Output: *a -> "mdev1", *b -> "ep81", *c -> "cdev" *d == NULL
- */
-static int split_string(char *buf, char **a, char **b, char **c, char **d)
-{
-	*a = strsep(&buf, ":");
-	if (!*a)
-		return -EIO;
-
-	*b = strsep(&buf, ":\n");
-	if (!*b)
-		return -EIO;
-
-	*c = strsep(&buf, ":\n");
-	if (!*c)
-		return -EIO;
-
-	if (d)
-		*d = strsep(&buf, ":\n");
-
-	return 0;
-}
-
-/**
  * get_channel - get pointer to channel
  * @mdev: name of the device interface
  * @mdev_ch: name of channel
@@ -675,13 +633,13 @@ int most_set_cfg_direction(char *mdev, char *mdev_ch, char *buf)
 
 	if (!c)
 		return -ENODEV;
-	if (!strcmp(buf, "dir_rx\n")) {
+	if (!strcmp(buf, "dir_rx")) {
 		c->cfg.direction = MOST_CH_RX;
-	} else if (!strcmp(buf, "rx\n")) {
+	} else if (!strcmp(buf, "rx")) {
 		c->cfg.direction = MOST_CH_RX;
-	} else if (!strcmp(buf, "dir_tx\n")) {
+	} else if (!strcmp(buf, "dir_tx")) {
 		c->cfg.direction = MOST_CH_TX;
-	} else if (!strcmp(buf, "tx\n")) {
+	} else if (!strcmp(buf, "tx")) {
 		c->cfg.direction = MOST_CH_TX;
 	} else {
 		pr_info("Invalid direction\n");
@@ -723,48 +681,6 @@ int most_add_link(char *mdev, char *mdev_ch, char *comp_name, char *link_name,
 	return link_channel_to_component(c, comp, link_name, comp_param);
 }
 
-/**
- * remove_link_store - store function for remove_link attribute
- * @drv: device driver
- * @buf: buffer
- * @len: buffer length
- *
- * Example:
- * echo "mdev0:ep81" >remove_link
- */
-static ssize_t remove_link_store(struct device_driver *drv,
-				 const char *buf,
-				 size_t len)
-{
-	struct most_channel *c;
-	struct core_component *comp;
-	char buffer[STRING_SIZE];
-	char *mdev;
-	char *mdev_ch;
-	char *comp_name;
-	int ret;
-	size_t max_len = min_t(size_t, len + 1, STRING_SIZE);
-
-	strlcpy(buffer, buf, max_len);
-	ret = split_string(buffer, &mdev, &mdev_ch, &comp_name, NULL);
-	if (ret)
-		return ret;
-	comp = match_component(comp_name);
-	if (!comp)
-		return -ENODEV;
-	c = get_channel(mdev, mdev_ch);
-	if (!c)
-		return -ENODEV;
-
-	if (comp->disconnect_channel(c->iface, c->channel_id))
-		return -EIO;
-	if (c->pipe0.comp == comp)
-		c->pipe0.comp = NULL;
-	if (c->pipe1.comp == comp)
-		c->pipe1.comp = NULL;
-	return len;
-}
-
 int most_remove_link(char *mdev, char *mdev_ch, char *comp_name)
 {
 	struct most_channel *c;
@@ -790,12 +706,10 @@ int most_remove_link(char *mdev, char *mdev_ch, char *comp_name)
 
 static DRIVER_ATTR_RO(links);
 static DRIVER_ATTR_RO(components);
-static DRIVER_ATTR_WO(remove_link);
 
 static struct attribute *mc_attrs[] = {
 	DRV_ATTR(links),
 	DRV_ATTR(components),
-	DRV_ATTR(remove_link),
 	NULL,
 };
 
diff --git a/drivers/staging/most/core.h b/drivers/staging/most/core.h
index 652aaa771029..49859aef98df 100644
--- a/drivers/staging/most/core.h
+++ b/drivers/staging/most/core.h
@@ -265,6 +265,7 @@ struct most_interface {
 struct core_component {
 	struct list_head list;
 	const char *name;
+	struct module *mod;
 	int (*probe_channel)(struct most_interface *iface, int channel_idx,
 			     struct most_channel_config *cfg, char *name,
 			     char *param);
diff --git a/drivers/staging/most/net/net.c b/drivers/staging/most/net/net.c
index 26a31854c636..6cab1bb8956e 100644
--- a/drivers/staging/most/net/net.c
+++ b/drivers/staging/most/net/net.c
@@ -498,6 +498,7 @@ put_nd:
 }
 
 static struct core_component comp = {
+	.mod = THIS_MODULE,
 	.name = "net",
 	.probe_channel = comp_probe_channel,
 	.disconnect_channel = comp_disconnect_channel,
diff --git a/drivers/staging/most/sound/sound.c b/drivers/staging/most/sound/sound.c
index 79817061fcfa..723d0bd1cc21 100644
--- a/drivers/staging/most/sound/sound.c
+++ b/drivers/staging/most/sound/sound.c
@@ -344,8 +344,7 @@ static int pcm_hw_params(struct snd_pcm_substream *substream,
 		pr_err("Requested number of channels not supported.\n");
 		return -EINVAL;
 	}
-	return snd_pcm_lib_alloc_vmalloc_buffer(substream,
-						params_buffer_bytes(hw_params));
+	return snd_pcm_lib_malloc_pages(substream, params_buffer_bytes(hw_params));
 }
 
 /**
@@ -359,7 +358,7 @@ static int pcm_hw_params(struct snd_pcm_substream *substream,
  */
 static int pcm_hw_free(struct snd_pcm_substream *substream)
 {
-	return snd_pcm_lib_free_vmalloc_buffer(substream);
+	return snd_pcm_lib_free_pages(substream);
 }
 
 /**
@@ -469,7 +468,6 @@ static const struct snd_pcm_ops pcm_ops = {
 	.prepare    = pcm_prepare,
 	.trigger    = pcm_trigger,
 	.pointer    = pcm_pointer,
-	.page       = snd_pcm_lib_get_vmalloc_page,
 };
 
 static int split_arg_list(char *buf, u16 *ch_num, char **sample_res)
@@ -663,6 +661,8 @@ skip_adpt_alloc:
 	pcm->private_data = channel;
 	strscpy(pcm->name, device_name, sizeof(pcm->name));
 	snd_pcm_set_ops(pcm, direction, &pcm_ops);
+	snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_VMALLOC,
+					      NULL, 0, 0);
 
 	return 0;
 
@@ -782,6 +782,7 @@ static int audio_tx_completion(struct most_interface *iface, int channel_id)
  * Initialization of the struct core_component
  */
 static struct core_component comp = {
+	.mod = THIS_MODULE,
 	.name = DRIVER_NAME,
 	.probe_channel = audio_probe_channel,
 	.disconnect_channel = audio_disconnect_channel,
diff --git a/drivers/staging/most/video/video.c b/drivers/staging/most/video/video.c
index 250af9fb704d..10c1ef7e3a3e 100644
--- a/drivers/staging/most/video/video.c
+++ b/drivers/staging/most/video/video.c
@@ -528,6 +528,7 @@ static int comp_disconnect_channel(struct most_interface *iface,
 }
 
 static struct core_component comp = {
+	.mod = THIS_MODULE,
 	.name = "video",
 	.probe_channel = comp_probe_channel,
 	.disconnect_channel = comp_disconnect_channel,