eventfs: Have the inodes all for files and directories all be the same

The dentries and inodes are created in the readdir for the sole purpose of
getting a consistent inode number. Linus stated that is unnecessary, and
that all inodes can have the same inode number. For a virtual file system
they are pretty meaningless.

Instead use a single unique inode number for all files and one for all
directories.

Link: https://lore.kernel.org/all/20240116133753.2808d45e@gandalf.local.home/
Link: https://lore.kernel.org/linux-trace-kernel/20240116211353.412180363@goodmis.org

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Al  Viro <viro@ZenIV.linux.org.uk>
Cc: Ajay Kaher <ajay.kaher@broadcom.com>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
This commit is contained in:
Steven Rostedt (Google) 2024-01-16 16:12:18 -05:00
parent 1de94b52d5
commit 53c41052ba

View File

@ -32,6 +32,10 @@
*/
static DEFINE_MUTEX(eventfs_mutex);
/* Choose something "unique" ;-) */
#define EVENTFS_FILE_INODE_INO 0x12c4e37
#define EVENTFS_DIR_INODE_INO 0x134b2f5
/*
* The eventfs_inode (ei) itself is protected by SRCU. It is released from
* its parent's list and will have is_freed set (under eventfs_mutex).
@ -352,6 +356,9 @@ static struct dentry *create_file(const char *name, umode_t mode,
inode->i_fop = fop;
inode->i_private = data;
/* All files will have the same inode number */
inode->i_ino = EVENTFS_FILE_INODE_INO;
ti = get_tracefs(inode);
ti->flags |= TRACEFS_EVENT_INODE;
d_instantiate(dentry, inode);
@ -388,6 +395,9 @@ static struct dentry *create_dir(struct eventfs_inode *ei, struct dentry *parent
inode->i_op = &eventfs_root_dir_inode_operations;
inode->i_fop = &eventfs_file_operations;
/* All directories will have the same inode number */
inode->i_ino = EVENTFS_DIR_INODE_INO;
ti = get_tracefs(inode);
ti->flags |= TRACEFS_EVENT_INODE;