[PATCH 28/34] vfs: Add some logging to the core users of the fs_context log [ver #12]

From: David Howells
Date: Fri Sep 21 2018 - 12:34:02 EST


Add some logging to the core users of the fs_context log so that
information can be extracted from them as to the reason for failure.

Signed-off-by: David Howells <dhowells@xxxxxxxxxx>
---

fs/super.c | 4 +++-
kernel/cgroup/cgroup-v1.c | 2 +-
2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/fs/super.c b/fs/super.c
index de43b140bbb1..021cbdcc0e6e 100644
--- a/fs/super.c
+++ b/fs/super.c
@@ -1771,8 +1771,10 @@ int vfs_get_tree(struct fs_context *fc)
struct super_block *sb;
int ret;

- if (fc->fs_type->fs_flags & FS_REQUIRES_DEV && !fc->source)
+ if (fc->fs_type->fs_flags & FS_REQUIRES_DEV && !fc->source) {
+ errorf(fc, "Filesystem requires source device");
return -ENOENT;
+ }

if (fc->root)
return -EBUSY;
diff --git a/kernel/cgroup/cgroup-v1.c b/kernel/cgroup/cgroup-v1.c
index d8b325c3c2eb..d5ae888b8c57 100644
--- a/kernel/cgroup/cgroup-v1.c
+++ b/kernel/cgroup/cgroup-v1.c
@@ -17,7 +17,7 @@

#include <trace/events/cgroup.h>

-#define cg_invalf(fc, fmt, ...) ({ pr_err(fmt, ## __VA_ARGS__); -EINVAL; })
+#define cg_invalf(fc, fmt, ...) invalf(fc, fmt, ## __VA_ARGS__)

/*
* pidlists linger the following amount before being destroyed. The goal