Small collection of macros taken from mmdebug.h
Signed-off-by: Mateusz Guzik <mjguzik@xxxxxxxxx>
---
include/linux/fs.h | 1 +
include/linux/vfsdebug.h | 50 ++++++++++++++++++++++++++++++++++++++++
lib/Kconfig.debug | 9 ++++++++
3 files changed, 60 insertions(+)
create mode 100644 include/linux/vfsdebug.h
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 1437a3323731..034745af9702 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -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>
diff --git a/include/linux/vfsdebug.h b/include/linux/vfsdebug.h
new file mode 100644
index 000000000000..b1a2c776992a
--- /dev/null
+++ b/include/linux/vfsdebug.h
@@ -0,0 +1,50 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef LINUX_VFS_DEBUG_H
+#define LINUX_VFS_DEBUG_H 1
+
+#include <linux/bug.h>
+#include <linux/stringify.h>
+
+struct inode;
+
+#ifdef CONFIG_DEBUG_VFS
+/*
+ * TODO: add a proper inode dumping routine, this is a stub to get debug off the ground
+ */
+static inline void dump_inode(struct inode *inode, const char *reason) {
+ pr_crit("%s failed for inode %px", reason, inode);
+}
+#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(" __stringify(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(" __stringify(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
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 1af972a92d06..c08ce985c482 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -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
--
2.43.0
