From: Hridya Valsaraju <hri...@google.com> Currently, since each binderfs instance needs its own private binder devices, every time a binderfs instance is mounted, all the default binder devices need to be created via the BINDER_CTL_ADD IOCTL. This patch aims to add a solution to automatically create the default binder devices for each binderfs instance that gets mounted. To achieve this goal, when 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.brau...@ubuntu.com> Signed-off-by: Christian Brauner <christian.brau...@ubuntu.com> Signed-off-by: Hridya Valsaraju <hri...@google.com> Reviewed-by: Joel Fernandes (Google) <j...@joelfernandes.org> Link: https://lore.kernel.org/r/20190808222727.132744-2-hri...@google.com --- drivers/android/binder.c | 5 +++-- drivers/android/binder_internal.h | 2 ++ drivers/android/binderfs.c | 23 ++++++++++++++++++++--- 3 files changed, 25 insertions(+), 5 deletions(-) diff --git a/drivers/android/binder.c b/drivers/android/binder.c index dc1c83eafc22..ef2d3e582368 100644 --- a/drivers/android/binder.c +++ b/drivers/android/binder.c @@ -122,7 +122,7 @@ static uint32_t binder_debug_mask = BINDER_DEBUG_USER_ERROR | BINDER_DEBUG_FAILED_TRANSACTION | BINDER_DEBUG_DEAD_TRANSACTION; module_param_named(debug_mask, binder_debug_mask, uint, 0644); -static char *binder_devices_param = CONFIG_ANDROID_BINDER_DEVICES; +char *binder_devices_param = CONFIG_ANDROID_BINDER_DEVICES; module_param_named(devices, binder_devices_param, charp, 0444); static DECLARE_WAIT_QUEUE_HEAD(binder_user_error_wait); @@ -6131,7 +6131,8 @@ 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/binder_internal.h b/drivers/android/binder_internal.h index 045b3e42d98b..fe8c745dc8e0 100644 --- a/drivers/android/binder_internal.h +++ b/drivers/android/binder_internal.h @@ -37,6 +37,8 @@ struct binder_device { extern const struct file_operations binder_fops; +extern char *binder_devices_param; + #ifdef CONFIG_ANDROID_BINDERFS extern bool is_binderfs_device(const struct inode *inode); #else diff --git a/drivers/android/binderfs.c b/drivers/android/binderfs.c index e773f45d19d9..aee46dd1be91 100644 --- a/drivers/android/binderfs.c +++ b/drivers/android/binderfs.c @@ -186,8 +186,7 @@ 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 +466,9 @@ 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 +523,22 @@ 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, ",")) { + 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, -- 2.23.0 _______________________________________________ devel mailing list de...@linuxdriverproject.org http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
