Unverified Commit 8b17e540 authored by Mateusz Guzik's avatar Mateusz Guzik Committed by Christian Brauner
Browse files

vfs: add initial support for CONFIG_DEBUG_VFS 



Small collection of macros taken from mmdebug.h

Signed-off-by: default avatarMateusz Guzik <mjguzik@gmail.com>
Link: https://lore.kernel.org/r/20250209185523.745956-2-mjguzik@gmail.com


Reviewed-by: default avatarJan Kara <jack@suse.cz>
Signed-off-by: default avatarChristian Brauner <brauner@kernel.org>
parent 2014c95a

fs/inode.c

+15 −0
Original line number Diff line number Diff line
@@ -2953,3 +2953,18 @@ umode_t mode_strip_sgid(struct mnt_idmap *idmap, 
	return mode & ~S_ISGID;

}

EXPORT_SYMBOL(mode_strip_sgid);



#ifdef CONFIG_DEBUG_VFS

/*

 * Dump an inode.

 *

 * TODO: add a proper inode dumping routine, this is a stub to get debug off the

 * ground.

 */

void dump_inode(struct inode *inode, const char *reason)

{

       pr_warn("%s encountered for inode %px", reason, inode);

}



EXPORT_SYMBOL(dump_inode);

#endif

include/linux/fs.h

+1 −0
Original line number Diff line number Diff line
@@ -2,6 +2,7 @@ 
#ifndef _LINUX_FS_H

#define _LINUX_FS_H



#include <linux/vfsdebug.h>

#include <linux/linkage.h>

#include <linux/wait_bit.h>

#include <linux/kdev_t.h>

include/linux/vfsdebug.h

0 → 100644
+45 −0
Original line number Diff line number Diff line 
/* SPDX-License-Identifier: GPL-2.0 */

#ifndef LINUX_VFS_DEBUG_H

#define LINUX_VFS_DEBUG_H 1



#include <linux/bug.h>



struct inode;



#ifdef CONFIG_DEBUG_VFS

void dump_inode(struct inode *inode, const char *reason);



#define VFS_BUG_ON(cond) BUG_ON(cond)

#define VFS_WARN_ON(cond) (void)WARN_ON(cond)

#define VFS_WARN_ON_ONCE(cond) (void)WARN_ON_ONCE(cond)

#define VFS_WARN_ONCE(cond, format...) (void)WARN_ONCE(cond, format)

#define VFS_WARN(cond, format...) (void)WARN(cond, format)



#define VFS_BUG_ON_INODE(cond, inode)		({			\

	if (unlikely(!!(cond))) {					\

		dump_inode(inode, "VFS_BUG_ON_INODE(" #cond")");\

		BUG_ON(1);						\

	}								\

})



#define VFS_WARN_ON_INODE(cond, inode)		({			\

	int __ret_warn = !!(cond);					\

									\

	if (unlikely(__ret_warn)) {					\

		dump_inode(inode, "VFS_WARN_ON_INODE(" #cond")");\

		WARN_ON(1);						\

	}								\

	unlikely(__ret_warn);						\

})

#else

#define VFS_BUG_ON(cond) BUILD_BUG_ON_INVALID(cond)

#define VFS_WARN_ON(cond) BUILD_BUG_ON_INVALID(cond)

#define VFS_WARN_ON_ONCE(cond) BUILD_BUG_ON_INVALID(cond)

#define VFS_WARN_ONCE(cond, format...) BUILD_BUG_ON_INVALID(cond)

#define VFS_WARN(cond, format...) BUILD_BUG_ON_INVALID(cond)



#define VFS_BUG_ON_INODE(cond, inode) VFS_BUG_ON(cond)

#define VFS_WARN_ON_INODE(cond, inode)  BUILD_BUG_ON_INVALID(cond)

#endif /* CONFIG_DEBUG_VFS */



#endif

lib/Kconfig.debug

+9 −0
Original line number Diff line number Diff line
@@ -808,6 +808,15 @@ config ARCH_HAS_DEBUG_VM_PGTABLE 
	  An architecture should select this when it can successfully

	  build and run DEBUG_VM_PGTABLE.



config DEBUG_VFS

	bool "Debug VFS"

	depends on DEBUG_KERNEL

	help

	  Enable this to turn on extended checks in the VFS layer that may impact

	  performance.



	  If unsure, say N.



config DEBUG_VM_IRQSOFF

	def_bool DEBUG_VM && !PREEMPT_RT