Adding following function to eventfs to add files:
eventfs_add_top_file() adds the info of top file to eventfs and dynamically create these files when they are accessed.
eventfs_add_file() adds the info of nested files to eventfs and dynamically create these files when they are accessed.
Signed-off-by: Ajay Kaher akaher@vmware.com Co-developed-by: Steven Rostedt (VMware) rostedt@goodmis.org Signed-off-by: Steven Rostedt (VMware) rostedt@goodmis.org Tested-by: Ching-lin Yu chinglinyu@google.com Reported-by: kernel test robot lkp@intel.com Closes: https://lore.kernel.org/oe-lkp/202305051619.9a469a9a-yujie.liu@intel.com --- fs/tracefs/event_inode.c | 84 ++++++++++++++++++++++++++++++++++++++++ include/linux/tracefs.h | 8 ++++ 2 files changed, 92 insertions(+)
diff --git a/fs/tracefs/event_inode.c b/fs/tracefs/event_inode.c index 4e7a8eccaa0b..75dc8953d813 100644 --- a/fs/tracefs/event_inode.c +++ b/fs/tracefs/event_inode.c @@ -215,3 +215,87 @@ struct eventfs_file *eventfs_add_dir(const char *name, mutex_unlock(&eventfs_mutex); return ef; } + +/** + * eventfs_add_top_file - add event top file to list to create later + * @name: the name of the file to create. + * @mode: the permission that the file should have. + * @parent: parent dentry for this file. + * @data: something that the caller will want to get to later on. The + * inode.i_private pointer will point to this value on the open() call. + * @fop: struct file_operations that should be used for this file. + * + * This function adds top files of event dir to list. + * And all these files are created on the fly when they are looked up, + * and the dentry and inodes will be removed when they are done. + */ +int eventfs_add_top_file(const char *name, umode_t mode, + struct dentry *parent, void *data, + const struct file_operations *fop) +{ + struct tracefs_inode *ti; + struct eventfs_inode *ei; + struct eventfs_file *ef; + + if (!parent) + return -EINVAL; + + if (!(mode & S_IFMT)) + mode |= S_IFREG; + + if (!parent->d_inode) + return -EINVAL; + + ti = get_tracefs(parent->d_inode); + if (!(ti->flags & TRACEFS_EVENT_INODE)) + return -EINVAL; + + ei = ti->private; + ef = eventfs_prepare_ef(name, mode, fop, NULL, data); + + if (IS_ERR(ef)) + return -ENOMEM; + + mutex_lock(&eventfs_mutex); + list_add_tail(&ef->list, &ei->e_top_files); + ef->d_parent = parent; + mutex_unlock(&eventfs_mutex); + return 0; +} + +/** + * eventfs_add_file - add eventfs file to list to create later + * @name: the name of the file to create. + * @mode: the permission that the file should have. + * @ef_parent: parent eventfs_file for this file. + * @data: something that the caller will want to get to later on. The + * inode.i_private pointer will point to this value on the open() call. + * @fop: struct file_operations that should be used for this file. + * + * This function adds top files of event dir to list. + * And all these files are created on the fly when they are looked up, + * and the dentry and inodes will be removed when they are done. + */ +int eventfs_add_file(const char *name, umode_t mode, + struct eventfs_file *ef_parent, + void *data, + const struct file_operations *fop) +{ + struct eventfs_file *ef; + + if (!ef_parent) + return -EINVAL; + + if (!(mode & S_IFMT)) + mode |= S_IFREG; + + ef = eventfs_prepare_ef(name, mode, fop, NULL, data); + if (IS_ERR(ef)) + return -ENOMEM; + + mutex_lock(&eventfs_mutex); + list_add_tail(&ef->list, &ef_parent->ei->e_top_files); + ef->d_parent = ef_parent->dentry; + mutex_unlock(&eventfs_mutex); + return 0; +} diff --git a/include/linux/tracefs.h b/include/linux/tracefs.h index 432e5e6f7901..a51312ff803c 100644 --- a/include/linux/tracefs.h +++ b/include/linux/tracefs.h @@ -32,6 +32,14 @@ struct eventfs_file *eventfs_add_subsystem_dir(const char *name, struct eventfs_file *eventfs_add_dir(const char *name, struct eventfs_file *ef_parent);
+int eventfs_add_file(const char *name, umode_t mode, + struct eventfs_file *ef_parent, void *data, + const struct file_operations *fops); + +int eventfs_add_top_file(const char *name, umode_t mode, + struct dentry *parent, void *data, + const struct file_operations *fops); + struct dentry *tracefs_create_file(const char *name, umode_t mode, struct dentry *parent, void *data, const struct file_operations *fops);