Merge tag 'asoc-v5.1' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-next

ASoC: Updates for v5.1

Lots and lots of new drivers so far, a highlight being the MediaTek
BTCVSD which is a driver for a Bluetooth radio chip - the first such
driver we've had upstream.  Hopefully we will soon also see a baseband
with an upstream driver!

 - Support for only powering up channels that are actively being used.
 - Quite a few improvements to simplify the generic card drivers,
   especially the merge of the SCU cards into the main generic drivers.
 - Lots of fixes for probing on Intel systems, trying to rationalize
   things to look more standard from a framework point of view.
 - New drivers for Asahi Kasei Microdevices AK4497, Cirrus Logic CS4341,
   Google ChromeOS embedded controllers, Ingenic JZ4725B, MediaTek
   BTCVSD, MT8183 and MT6358, NXP MICFIL, Rockchip RK3328, Spreadtrum
   DMA controllers, Qualcomm WCD9335, Xilinx S/PDIF and PCM formatters.

1 files changed, 151 insertions, 131 deletions

diff --git a/drivers/android/binderfs.c b/drivers/android/binderfs.c
index 7496b10532aaf..6a2185eb66c59 100644
--- a/drivers/android/binderfs.c
+++ b/drivers/android/binderfs.c
@@ -11,6 +11,7 @@
 #include <linux/kdev_t.h>
 #include <linux/kernel.h>
 #include <linux/list.h>
+#include <linux/namei.h>
 #include <linux/magic.h>
 #include <linux/major.h>
 #include <linux/miscdevice.h>
@@ -20,6 +21,7 @@
 #include <linux/parser.h>
 #include <linux/radix-tree.h>
 #include <linux/sched.h>
+#include <linux/seq_file.h>
 #include <linux/slab.h>
 #include <linux/spinlock_types.h>
 #include <linux/stddef.h>
@@ -30,7 +32,7 @@
 #include <linux/xarray.h>
 #include <uapi/asm-generic/errno-base.h>
 #include <uapi/linux/android/binder.h>
-#include <uapi/linux/android/binder_ctl.h>
+#include <uapi/linux/android/binderfs.h>
 
 #include "binder_internal.h"
 
@@ -39,14 +41,32 @@
 #define INODE_OFFSET 3
 #define INTSTRLEN 21
 #define BINDERFS_MAX_MINOR (1U << MINORBITS)
-
-static struct vfsmount *binderfs_mnt;
+/* Ensure that the initial ipc namespace always has devices available. */
+#define BINDERFS_MAX_MINOR_CAPPED (BINDERFS_MAX_MINOR - 4)
 
 static dev_t binderfs_dev;
 static DEFINE_MUTEX(binderfs_minors_mutex);
 static DEFINE_IDA(binderfs_minors);
 
 /**
+ * binderfs_mount_opts - mount options for binderfs
+ * @max: maximum number of allocatable binderfs binder devices
+ */
+struct binderfs_mount_opts {
+	int max;
+};
+
+enum {
+	Opt_max,
+	Opt_err
+};
+
+static const match_table_t tokens = {
+	{ Opt_max, "max=%d" },
+	{ Opt_err, NULL     }
+};
+
+/**
  * binderfs_info - information about a binderfs mount
  * @ipc_ns:         The ipc namespace the binderfs mount belongs to.
  * @control_dentry: This records the dentry of this binderfs mount
@@ -55,13 +75,16 @@ static DEFINE_IDA(binderfs_minors);
  *                  created.
  * @root_gid:       gid that needs to be used when a new binder device is
  *                  created.
+ * @mount_opts:     The mount options in use.
+ * @device_count:   The current number of allocated binder devices.
  */
 struct binderfs_info {
 	struct ipc_namespace *ipc_ns;
 	struct dentry *control_dentry;
 	kuid_t root_uid;
 	kgid_t root_gid;
-
+	struct binderfs_mount_opts mount_opts;
+	int device_count;
 };
 
 static inline struct binderfs_info *BINDERFS_I(const struct inode *inode)
@@ -84,7 +107,7 @@ bool is_binderfs_device(const struct inode *inode)
  * @userp:     buffer to copy information about new device for userspace to
  * @req:       struct binderfs_device as copied from userspace
  *
- * This function allocated a new binder_device and reserves a new minor
+ * This function allocates a new binder_device and reserves a new minor
  * number for it.
  * Minor numbers are limited and tracked globally in binderfs_minors. The
  * function will stash a struct binder_device for the specific binder
@@ -100,20 +123,34 @@ static int binderfs_binder_device_create(struct inode *ref_inode,
 					 struct binderfs_device *req)
 {
 	int minor, ret;
-	struct dentry *dentry, *dup, *root;
+	struct dentry *dentry, *root;
 	struct binder_device *device;
-	size_t name_len = BINDERFS_MAX_NAME + 1;
 	char *name = NULL;
+	size_t name_len;
 	struct inode *inode = NULL;
 	struct super_block *sb = ref_inode->i_sb;
 	struct binderfs_info *info = sb->s_fs_info;
+#if defined(CONFIG_IPC_NS)
+	bool use_reserve = (info->ipc_ns == &init_ipc_ns);
+#else
+	bool use_reserve = true;
+#endif
 
 	/* Reserve new minor number for the new device. */
 	mutex_lock(&binderfs_minors_mutex);
-	minor = ida_alloc_max(&binderfs_minors, BINDERFS_MAX_MINOR, GFP_KERNEL);
-	mutex_unlock(&binderfs_minors_mutex);
-	if (minor < 0)
+	if (++info->device_count <= info->mount_opts.max)
+		minor = ida_alloc_max(&binderfs_minors,
+				      use_reserve ? BINDERFS_MAX_MINOR :
+						    BINDERFS_MAX_MINOR_CAPPED,
+				      GFP_KERNEL);
+	else
+		minor = -ENOSPC;
+	if (minor < 0) {
+		--info->device_count;
+		mutex_unlock(&binderfs_minors_mutex);
 		return minor;
+	}
+	mutex_unlock(&binderfs_minors_mutex);
 
 	ret = -ENOMEM;
 	device = kzalloc(sizeof(*device), GFP_KERNEL);
@@ -132,12 +169,13 @@ static int binderfs_binder_device_create(struct inode *ref_inode,
 	inode->i_uid = info->root_uid;
 	inode->i_gid = info->root_gid;
 
-	name = kmalloc(name_len, GFP_KERNEL);
+	req->name[BINDERFS_MAX_NAME] = '\0'; /* NUL-terminate */
+	name_len = strlen(req->name);
+	/* Make sure to include terminating NUL byte */
+	name = kmemdup(req->name, name_len + 1, GFP_KERNEL);
 	if (!name)
 		goto err;
 
-	strscpy(name, req->name, name_len);
-
 	device->binderfs_inode = inode;
 	device->context.binder_context_mgr_uid = INVALID_UID;
 	device->context.name = name;
@@ -156,28 +194,25 @@ static int binderfs_binder_device_create(struct inode *ref_inode,
 
 	root = sb->s_root;
 	inode_lock(d_inode(root));
-	dentry = d_alloc_name(root, name);
-	if (!dentry) {
+
+	/* look it up */
+	dentry = lookup_one_len(name, root, name_len);
+	if (IS_ERR(dentry)) {
 		inode_unlock(d_inode(root));
-		ret = -ENOMEM;
+		ret = PTR_ERR(dentry);
 		goto err;
 	}
 
-	/* Verify that the name userspace gave us is not already in use. */
-	dup = d_lookup(root, &dentry->d_name);
-	if (dup) {
-		if (d_really_is_positive(dup)) {
-			dput(dup);
-			dput(dentry);
-			inode_unlock(d_inode(root));
-			ret = -EEXIST;
-			goto err;
-		}
-		dput(dup);
+	if (d_really_is_positive(dentry)) {
+		/* already exists */
+		dput(dentry);
+		inode_unlock(d_inode(root));
+		ret = -EEXIST;
+		goto err;
 	}
 
 	inode->i_private = device;
-	d_add(dentry, inode);
+	d_instantiate(dentry, inode);
 	fsnotify_create(root->d_inode, dentry);
 	inode_unlock(d_inode(root));
 
@@ -187,6 +222,7 @@ err:
 	kfree(name);
 	kfree(device);
 	mutex_lock(&binderfs_minors_mutex);
+	--info->device_count;
 	ida_free(&binderfs_minors, minor);
 	mutex_unlock(&binderfs_minors_mutex);
 	iput(inode);
@@ -232,6 +268,7 @@ static long binder_ctl_ioctl(struct file *file, unsigned int cmd,
 static void binderfs_evict_inode(struct inode *inode)
 {
 	struct binder_device *device = inode->i_private;
+	struct binderfs_info *info = BINDERFS_I(inode);
 
 	clear_inode(inode);
 
@@ -239,6 +276,7 @@ static void binderfs_evict_inode(struct inode *inode)
 		return;
 
 	mutex_lock(&binderfs_minors_mutex);
+	--info->device_count;
 	ida_free(&binderfs_minors, device->miscdev.minor);
 	mutex_unlock(&binderfs_minors_mutex);
 
@@ -246,43 +284,87 @@ static void binderfs_evict_inode(struct inode *inode)
 	kfree(device);
 }
 
+/**
+ * binderfs_parse_mount_opts - parse binderfs mount options
+ * @data: options to set (can be NULL in which case defaults are used)
+ */
+static int binderfs_parse_mount_opts(char *data,
+				     struct binderfs_mount_opts *opts)
+{
+	char *p;
+	opts->max = BINDERFS_MAX_MINOR;
+
+	while ((p = strsep(&data, ",")) != NULL) {
+		substring_t args[MAX_OPT_ARGS];
+		int token;
+		int max_devices;
+
+		if (!*p)
+			continue;
+
+		token = match_token(p, tokens, args);
+		switch (token) {
+		case Opt_max:
+			if (match_int(&args[0], &max_devices) ||
+			    (max_devices < 0 ||
+			     (max_devices > BINDERFS_MAX_MINOR)))
+				return -EINVAL;
+
+			opts->max = max_devices;
+			break;
+		default:
+			pr_err("Invalid mount options\n");
+			return -EINVAL;
+		}
+	}
+
+	return 0;
+}
+
+static int binderfs_remount(struct super_block *sb, int *flags, char *data)
+{
+	struct binderfs_info *info = sb->s_fs_info;
+	return binderfs_parse_mount_opts(data, &info->mount_opts);
+}
+
+static int binderfs_show_mount_opts(struct seq_file *seq, struct dentry *root)
+{
+	struct binderfs_info *info;
+
+	info = root->d_sb->s_fs_info;
+	if (info->mount_opts.max <= BINDERFS_MAX_MINOR)
+		seq_printf(seq, ",max=%d", info->mount_opts.max);
+
+	return 0;
+}
+
 static const struct super_operations binderfs_super_ops = {
-	.statfs = simple_statfs,
-	.evict_inode = binderfs_evict_inode,
+	.evict_inode    = binderfs_evict_inode,
+	.remount_fs	= binderfs_remount,
+	.show_options	= binderfs_show_mount_opts,
+	.statfs         = simple_statfs,
 };
 
+static inline bool is_binderfs_control_device(const struct dentry *dentry)
+{
+	struct binderfs_info *info = dentry->d_sb->s_fs_info;
+	return info->control_dentry == dentry;
+}
+
 static int binderfs_rename(struct inode *old_dir, struct dentry *old_dentry,
 			   struct inode *new_dir, struct dentry *new_dentry,
 			   unsigned int flags)
 {
-	struct inode *inode = d_inode(old_dentry);
-
-	/* binderfs doesn't support directories. */
-	if (d_is_dir(old_dentry))
+	if (is_binderfs_control_device(old_dentry) ||
+	    is_binderfs_control_device(new_dentry))
 		return -EPERM;
 
-	if (flags & ~RENAME_NOREPLACE)
-		return -EINVAL;
-
-	if (!simple_empty(new_dentry))
-		return -ENOTEMPTY;
-
-	if (d_really_is_positive(new_dentry))
-		simple_unlink(new_dir, new_dentry);
-
-	old_dir->i_ctime = old_dir->i_mtime = new_dir->i_ctime =
-		new_dir->i_mtime = inode->i_ctime = current_time(old_dir);
-
-	return 0;
+	return simple_rename(old_dir, old_dentry, new_dir, new_dentry, flags);
 }
 
 static int binderfs_unlink(struct inode *dir, struct dentry *dentry)
 {
-	/*
-	 * The control dentry is only ever touched during mount so checking it
-	 * here should not require us to take lock.
-	 */
-	if (BINDERFS_I(dir)->control_dentry == dentry)
+	if (is_binderfs_control_device(dentry))
 		return -EPERM;
 
 	return simple_unlink(dir, dentry);
@@ -318,8 +400,6 @@ static int binderfs_binder_ctl_create(struct super_block *sb)
 	if (!device)
 		return -ENOMEM;
 
-	inode_lock(d_inode(root));
-
 	/* If we have already created a binder-control node, return. */
 	if (info->control_dentry) {
 		ret = 0;
@@ -358,12 +438,10 @@ static int binderfs_binder_ctl_create(struct super_block *sb)
 	inode->i_private = device;
 	info->control_dentry = dentry;
 	d_add(dentry, inode);
-	inode_unlock(d_inode(root));
 
 	return 0;
 
 out:
-	inode_unlock(d_inode(root));
 	kfree(device);
 	iput(inode);
 
@@ -378,12 +456,9 @@ static const struct inode_operations binderfs_dir_inode_operations = {
 
 static int binderfs_fill_super(struct super_block *sb, void *data, int silent)
 {
+	int ret;
 	struct binderfs_info *info;
-	int ret = -ENOMEM;
 	struct inode *inode = NULL;
-	struct ipc_namespace *ipc_ns = sb->s_fs_info;
-
-	get_ipc_ns(ipc_ns);
 
 	sb->s_blocksize = PAGE_SIZE;
 	sb->s_blocksize_bits = PAGE_SHIFT;
@@ -405,11 +480,17 @@ static int binderfs_fill_super(struct super_block *sb, void *data, int silent)
 	sb->s_op = &binderfs_super_ops;
 	sb->s_time_gran = 1;
 
-	info = kzalloc(sizeof(struct binderfs_info), GFP_KERNEL);
-	if (!info)
-		goto err_without_dentry;
+	sb->s_fs_info = kzalloc(sizeof(struct binderfs_info), GFP_KERNEL);
+	if (!sb->s_fs_info)
+		return -ENOMEM;
+	info = sb->s_fs_info;
+
+	info->ipc_ns = get_ipc_ns(current->nsproxy->ipc_ns);
+
+	ret = binderfs_parse_mount_opts(data, &info->mount_opts);
+	if (ret)
+		return ret;
 
-	info->ipc_ns = ipc_ns;
 	info->root_gid = make_kgid(sb->s_user_ns, 0);
 	if (!gid_valid(info->root_gid))
 		info->root_gid = GLOBAL_ROOT_GID;
@@ -417,11 +498,9 @@ static int binderfs_fill_super(struct super_block *sb, void *data, int silent)
 	if (!uid_valid(info->root_uid))
 		info->root_uid = GLOBAL_ROOT_UID;
 
-	sb->s_fs_info = info;
-
 	inode = new_inode(sb);
 	if (!inode)
-		goto err_without_dentry;
+		return -ENOMEM;
 
 	inode->i_ino = FIRST_INODE;
 	inode->i_fop = &simple_dir_operations;
@@ -432,79 +511,28 @@ static int binderfs_fill_super(struct super_block *sb, void *data, int silent)
 
 	sb->s_root = d_make_root(inode);
 	if (!sb->s_root)
-		goto err_without_dentry;
-
-	ret = binderfs_binder_ctl_create(sb);
-	if (ret)
-		goto err_with_dentry;
-
-	return 0;
-
-err_with_dentry:
-	dput(sb->s_root);
-	sb->s_root = NULL;
-
-err_without_dentry:
-	put_ipc_ns(ipc_ns);
-	iput(inode);
-	kfree(info);
-
-	return ret;
-}
-
-static int binderfs_test_super(struct super_block *sb, void *data)
-{
-	struct binderfs_info *info = sb->s_fs_info;
-
-	if (info)
-		return info->ipc_ns == data;
-
-	return 0;
-}
+		return -ENOMEM;
 
-static int binderfs_set_super(struct super_block *sb, void *data)
-{
-	sb->s_fs_info = data;
-	return set_anon_super(sb, NULL);
+	return binderfs_binder_ctl_create(sb);
 }
 
 static struct dentry *binderfs_mount(struct file_system_type *fs_type,
 				     int flags, const char *dev_name,
 				     void *data)
 {
-	struct super_block *sb;
-	struct ipc_namespace *ipc_ns = current->nsproxy->ipc_ns;
-
-	if (!ns_capable(ipc_ns->user_ns, CAP_SYS_ADMIN))
-		return ERR_PTR(-EPERM);
-
-	sb = sget_userns(fs_type, binderfs_test_super, binderfs_set_super,
-			 flags, ipc_ns->user_ns, ipc_ns);
-	if (IS_ERR(sb))
-		return ERR_CAST(sb);
-
-	if (!sb->s_root) {
-		int ret = binderfs_fill_super(sb, data, flags & SB_SILENT ? 1 : 0);
-		if (ret) {
-			deactivate_locked_super(sb);
-			return ERR_PTR(ret);
-		}
-
-		sb->s_flags |= SB_ACTIVE;
-	}
-
-	return dget(sb->s_root);
+	return mount_nodev(fs_type, flags, data, binderfs_fill_super);
 }
 
 static void binderfs_kill_super(struct super_block *sb)
 {
 	struct binderfs_info *info = sb->s_fs_info;
 
+	kill_litter_super(sb);
+
 	if (info && info->ipc_ns)
 		put_ipc_ns(info->ipc_ns);
 
 	kfree(info);
-	kill_litter_super(sb);
 }
 
 static struct file_system_type binder_fs_type = {
@@ -530,14 +558,6 @@ static int __init init_binderfs(void)
 		return ret;
 	}
 
-	binderfs_mnt = kern_mount(&binder_fs_type);
-	if (IS_ERR(binderfs_mnt)) {
-		ret = PTR_ERR(binderfs_mnt);
-		binderfs_mnt = NULL;
-		unregister_filesystem(&binder_fs_type);
-		unregister_chrdev_region(binderfs_dev, BINDERFS_MAX_MINOR);
-	}
-
 	return ret;
 }