Commit 268b3611 authored by Al Viro's avatar Al Viro Committed by Greg Kroah-Hartman
Browse files

debugfs: separate cache for debugfs inodes 



Embed them into container (struct debugfs_inode_info, with nothing
else in it at the moment), set the cache up, etc.

Just the infrastructure changes letting us augment debugfs inodes
here; adding stuff will come at the next step.

Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
Reviewed-by: default avatarChristian Brauner <brauner@kernel.org>
Link: https://lore.kernel.org/r/20250112080705.141166-1-viro@zeniv.linux.org.uk


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent ee9c6938

fs/debugfs/inode.c

+34 −6
Original line number Diff line number Diff line
@@ -208,16 +208,34 @@ static int debugfs_show_options(struct seq_file *m, struct dentry *root) 
	return 0;

}



static struct kmem_cache *debugfs_inode_cachep __ro_after_init;



static void init_once(void *foo)

{

	struct debugfs_inode_info *info = foo;

	inode_init_once(&info->vfs_inode);

}



static struct inode *debugfs_alloc_inode(struct super_block *sb)

{

	struct debugfs_inode_info *info;

	info = alloc_inode_sb(sb, debugfs_inode_cachep, GFP_KERNEL);

	if (!info)

		return NULL;

	return &info->vfs_inode;

}



static void debugfs_free_inode(struct inode *inode)

{

	if (S_ISLNK(inode->i_mode))

		kfree(inode->i_link);

	free_inode_nonrcu(inode);

	kmem_cache_free(debugfs_inode_cachep, DEBUGFS_I(inode));

}



static const struct super_operations debugfs_super_operations = {

	.statfs		= simple_statfs,

	.show_options	= debugfs_show_options,

	.alloc_inode	= debugfs_alloc_inode,

	.free_inode	= debugfs_free_inode,

};
@@ -939,12 +957,22 @@ static int __init debugfs_init(void) 
	if (retval)

		return retval;



	retval = register_filesystem(&debug_fs_type);

	if (retval)

	debugfs_inode_cachep = kmem_cache_create("debugfs_inode_cache",

				sizeof(struct debugfs_inode_info), 0,

				SLAB_RECLAIM_ACCOUNT | SLAB_ACCOUNT,

				init_once);

	if (debugfs_inode_cachep == NULL) {

		sysfs_remove_mount_point(kernel_kobj, "debug");

	else

		debugfs_registered = true;

		return -ENOMEM;

	}



	retval = register_filesystem(&debug_fs_type);

	if (retval) { // Really not going to happen

		sysfs_remove_mount_point(kernel_kobj, "debug");

		kmem_cache_destroy(debugfs_inode_cachep);

		return retval;

	}

	debugfs_registered = true;

	return 0;

}

core_initcall(debugfs_init);

fs/debugfs/internal.h

+9 −0
Original line number Diff line number Diff line
@@ -11,6 +11,15 @@ 


struct file_operations;



struct debugfs_inode_info {

	struct inode vfs_inode;

};



static inline struct debugfs_inode_info *DEBUGFS_I(struct inode *inode)

{

	return container_of(inode, struct debugfs_inode_info, vfs_inode);

}



/* declared over in file.c */

extern const struct file_operations debugfs_noop_file_operations;

extern const struct file_operations debugfs_open_proxy_file_operations;