If CONFIG_ANDROID_BINDERFS is set, the default binder devices
specified by CONFIG_ANDROID_BINDER_DEVICES are created in each
binderfs instance instead of global devices being created by
the binder driver.
Co-developed-by: Christian Brauner <christian.brauner@xxxxxxxxxx>
Signed-off-by: Christian Brauner <christian.brauner@xxxxxxxxxx>
Signed-off-by: Hridya Valsaraju <hridya@xxxxxxxxxx>
---
drivers/android/binder.c | 3 ++-
drivers/android/binderfs.c | 46 ++++++++++++++++++++++++++++++++++----
2 files changed, 44 insertions(+), 5 deletions(-)
diff --git a/drivers/android/binder.c b/drivers/android/binder.c
index 466b6a7f8ab7..65a99ac26711 100644
--- a/drivers/android/binder.c
+++ b/drivers/android/binder.c
@@ -6279,7 +6279,8 @@ static int __init binder_init(void)
&transaction_log_fops);
}
- if (strcmp(binder_devices_param, "") != 0) {
+ if (!IS_ENABLED(CONFIG_ANDROID_BINDERFS) &&
+ strcmp(binder_devices_param, "") != 0) {
/*
* Copy the module_parameter string, because we don't want to
* tokenize it in-place.
diff --git a/drivers/android/binderfs.c b/drivers/android/binderfs.c
index e773f45d19d9..9f5ed50ffd70 100644
--- a/drivers/android/binderfs.c
+++ b/drivers/android/binderfs.c
@@ -48,6 +48,10 @@ static dev_t binderfs_dev;
static DEFINE_MUTEX(binderfs_minors_mutex);
static DEFINE_IDA(binderfs_minors);
+static char *binder_devices_param = CONFIG_ANDROID_BINDER_DEVICES;
+module_param_named(devices, binder_devices_param, charp, 0444);
+MODULE_PARM_DESC(devices, "Binder devices to be created by default");
+
/**
* binderfs_mount_opts - mount options for binderfs
* @max: maximum number of allocatable binderfs binder devices
@@ -135,7 +139,6 @@ static int binderfs_binder_device_create(struct inode *ref_inode,
#else
bool use_reserve = true;
#endif
-
/* Reserve new minor number for the new device. */
mutex_lock(&binderfs_minors_mutex);
if (++info->device_count <= info->mount_opts.max)
@@ -186,8 +189,7 @@ static int binderfs_binder_device_create(struct inode *ref_inode,
req->major = MAJOR(binderfs_dev);
req->minor = minor;
- ret = copy_to_user(userp, req, sizeof(*req));
- if (ret) {
+ if (userp && copy_to_user(userp, req, sizeof(*req))) {
ret = -EFAULT;
goto err;
}
@@ -467,6 +469,9 @@ static int binderfs_fill_super(struct super_block *sb, void *data, int silent)
int ret;
struct binderfs_info *info;
struct inode *inode = NULL;
+ struct binderfs_device device_info = { 0 };
+ const char *name;
+ size_t len;
sb->s_blocksize = PAGE_SIZE;
sb->s_blocksize_bits = PAGE_SHIFT;
@@ -521,7 +526,28 @@ static int binderfs_fill_super(struct super_block *sb, void *data, int silent)
if (!sb->s_root)
return -ENOMEM;
- return binderfs_binder_ctl_create(sb);
+ ret = binderfs_binder_ctl_create(sb);
+ if (ret)
+ return ret;
+
+ name = binder_devices_param;
+ for (len = strcspn(name, ","); len > 0; len = strcspn(name, ",")) {
+ /*
+ * init_binderfs() has already checked that the length of
+ * device_name_entry->name is not greater than device_info.name.
+ */
+ strscpy(device_info.name, name, len + 1);
+ ret = binderfs_binder_device_create(inode, NULL, &device_info);
+ if (ret)
+ return ret;
+ name += len;
+ if (*name == ',')
+ name++;
+
+ }
+
+ return 0;
+
}
static struct dentry *binderfs_mount(struct file_system_type *fs_type,
@@ -553,6 +579,18 @@ static struct file_system_type binder_fs_type = {
int __init init_binderfs(void)
{
int ret;
+ const char *name;
+ size_t len;
+
+ /* Verify that the default binderfs device names are valid. */
+ name = binder_devices_param;
+ for (len = strcspn(name, ","); len > 0; len = strcspn(name, ",")) {
+ if (len > BINDERFS_MAX_NAME)
+ return -E2BIG;
+ name += len;
+ if (*name == ',')
+ name++;
+ }
/* Allocate new major number for binderfs. */
ret = alloc_chrdev_region(&binderfs_dev, 0, BINDERFS_MAX_MINOR,
--
2.22.0.770.g0f2c4a37fd-goog
_______________________________________________
devel mailing list
devel@xxxxxxxxxxxxxxxxxxxxxx
http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
