From: Tejun Heo <tj@kernel.org>
To: gregkh@linuxfoundation.org
Cc: kay@vrfy.org, linux-kernel@vger.kernel.org,
ebiederm@xmission.com, bhelgaas@google.com,
Tejun Heo <tj@kernel.org>
Subject: [PATCH 22/39] sysfs, kernfs: revamp sysfs_dirent active_ref lockdep annotation
Date: Sun, 3 Nov 2013 04:53:01 -0500 [thread overview]
Message-ID: <1383472398-17812-23-git-send-email-tj@kernel.org> (raw)
In-Reply-To: <1383472398-17812-1-git-send-email-tj@kernel.org>
Currently, sysfs_dirent active_ref lockdep annotation uses
attribute->[s]key as the lockdep key, which forces
kernfs_create_file_ns() to assume that sysfs_dirent->priv is pointing
to a struct attribute which may not be true for non-sysfs users. This
patch restructures the lockdep annotation such that
* kernfs_ops contains lockdep_key which is used by default for files
created kernfs_create_file_ns().
* kernfs_create_file_ns_key() is introduced which takes an extra @key
argument. The created file will use the specified key for
active_ref lockdep annotation. If NULL is specified, lockdep for
the file is disabled.
* sysfs_add_file_mode_ns() is updated to use
kernfs_create_file_ns_key() with the appropriate key from the
attribute or NULL if ignore_lockdep is set.
This makes the lockdep annotation properly contained in kernfs while
allowing sysfs to cleanly keep its current behavior. This patch
doesn't introduce any behavior differences.
Signed-off-by: Tejun Heo <tj@kernel.org>
---
fs/sysfs/dir.c | 4 ++--
fs/sysfs/file.c | 35 ++++++++++++++++++++++++-----------
fs/sysfs/sysfs.h | 32 +-------------------------------
include/linux/kernfs.h | 37 +++++++++++++++++++++++++++++--------
4 files changed, 56 insertions(+), 52 deletions(-)
diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c
index 14693aa..1933718 100644
--- a/fs/sysfs/dir.c
+++ b/fs/sysfs/dir.c
@@ -162,7 +162,7 @@ struct sysfs_dirent *sysfs_get_active(struct sysfs_dirent *sd)
if (!atomic_inc_unless_negative(&sd->s_active))
return NULL;
- if (likely(!sysfs_ignore_lockdep(sd)))
+ if (sd->s_flags & SYSFS_FLAG_LOCKDEP)
rwsem_acquire_read(&sd->dep_map, 0, 1, _RET_IP_);
return sd;
}
@@ -181,7 +181,7 @@ void sysfs_put_active(struct sysfs_dirent *sd)
if (unlikely(!sd))
return;
- if (likely(!sysfs_ignore_lockdep(sd)))
+ if (sd->s_flags & SYSFS_FLAG_LOCKDEP)
rwsem_release(&sd->dep_map, 1, _RET_IP_);
v = atomic_dec_return(&sd->s_active);
if (likely(v != SD_DEACTIVATED_BIAS))
diff --git a/fs/sysfs/file.c b/fs/sysfs/file.c
index 1f99fe3..eabc1d2 100644
--- a/fs/sysfs/file.c
+++ b/fs/sysfs/file.c
@@ -58,7 +58,7 @@ static struct sysfs_open_file *sysfs_of(struct file *file)
*/
static const struct kernfs_ops *kernfs_ops(struct sysfs_dirent *sd)
{
- if (!sysfs_ignore_lockdep(sd))
+ if (sd->s_flags & SYSFS_FLAG_LOCKDEP)
lockdep_assert_held(sd);
return sd->s_attr.ops;
}
@@ -71,7 +71,7 @@ static const struct sysfs_ops *sysfs_file_ops(struct sysfs_dirent *sd)
{
struct kobject *kobj = sd->s_parent->priv;
- if (!sysfs_ignore_lockdep(sd))
+ if (sd->s_flags & SYSFS_FLAG_LOCKDEP)
lockdep_assert_held(sd);
return kobj->ktype ? kobj->ktype->sysfs_ops : NULL;
}
@@ -925,6 +925,7 @@ int sysfs_add_file_mode_ns(struct sysfs_dirent *dir_sd,
const struct attribute *attr, bool is_bin,
umode_t mode, const void *ns)
{
+ struct lock_class_key *key = NULL;
const struct kernfs_ops *ops;
struct sysfs_dirent *sd;
loff_t size;
@@ -964,8 +965,12 @@ int sysfs_add_file_mode_ns(struct sysfs_dirent *dir_sd,
size = battr->size;
}
- sd = kernfs_create_file_ns(dir_sd, attr->name, mode, size,
- ops, (void *)attr, ns);
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+ if (!attr->ignore_lockdep)
+ key = attr->key ?: (struct lock_class_key *)&attr->skey;
+#endif
+ sd = kernfs_create_file_ns_key(dir_sd, attr->name, mode, size,
+ ops, (void *)attr, ns, key);
if (IS_ERR(sd)) {
if (PTR_ERR(sd) == -EEXIST)
sysfs_warn_dup(dir_sd, attr->name);
@@ -975,7 +980,7 @@ int sysfs_add_file_mode_ns(struct sysfs_dirent *dir_sd,
}
/**
- * kernfs_create_file_ns - create a file
+ * kernfs_create_file_ns_key - create a file
* @parent: directory to create the file in
* @name: name of the file
* @mode: mode of the file
@@ -983,14 +988,16 @@ int sysfs_add_file_mode_ns(struct sysfs_dirent *dir_sd,
* @ops: kernfs operations for the file
* @priv: private data for the file
* @ns: optional namespace tag of the file
+ * @key: lockdep key for the file's active_ref, %NULL to disable lockdep
*
* Returns the created node on success, ERR_PTR() value on error.
*/
-struct sysfs_dirent *kernfs_create_file_ns(struct sysfs_dirent *parent,
- const char *name,
- umode_t mode, loff_t size,
- const struct kernfs_ops *ops,
- void *priv, const void *ns)
+struct sysfs_dirent *kernfs_create_file_ns_key(struct sysfs_dirent *parent,
+ const char *name,
+ umode_t mode, loff_t size,
+ const struct kernfs_ops *ops,
+ void *priv, const void *ns,
+ struct lock_class_key *key)
{
struct sysfs_addrm_cxt acxt;
struct sysfs_dirent *sd;
@@ -1005,7 +1012,13 @@ struct sysfs_dirent *kernfs_create_file_ns(struct sysfs_dirent *parent,
sd->s_attr.size = size;
sd->s_ns = ns;
sd->priv = priv;
- sysfs_dirent_init_lockdep(sd);
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+ if (key) {
+ lockdep_init_map(&sd->dep_map, "s_active", key, 0);
+ sd->s_flags |= SYSFS_FLAG_LOCKDEP;
+ }
+#endif
/*
* sd->s_attr.ops is accesible only while holding active ref. We
diff --git a/fs/sysfs/sysfs.h b/fs/sysfs/sysfs.h
index 83f4708..bffaa5b 100644
--- a/fs/sysfs/sysfs.h
+++ b/fs/sysfs/sysfs.h
@@ -92,43 +92,13 @@ struct sysfs_dirent {
#define SYSFS_FLAG_HAS_NS 0x0020
#define SYSFS_FLAG_HAS_SEQ_SHOW 0x0040
#define SYSFS_FLAG_HAS_MMAP 0x0080
+#define SYSFS_FLAG_LOCKDEP 0x0100
static inline unsigned int sysfs_type(struct sysfs_dirent *sd)
{
return sd->s_flags & SYSFS_TYPE_MASK;
}
-#ifdef CONFIG_DEBUG_LOCK_ALLOC
-
-#define sysfs_dirent_init_lockdep(sd) \
-do { \
- struct attribute *attr = sd->priv; \
- struct lock_class_key *key = attr->key; \
- if (!key) \
- key = &attr->skey; \
- \
- lockdep_init_map(&sd->dep_map, "s_active", key, 0); \
-} while (0)
-
-/* Test for attributes that want to ignore lockdep for read-locking */
-static inline bool sysfs_ignore_lockdep(struct sysfs_dirent *sd)
-{
- struct attribute *attr = sd->priv;
-
- return sysfs_type(sd) == SYSFS_KOBJ_ATTR && attr->ignore_lockdep;
-}
-
-#else
-
-#define sysfs_dirent_init_lockdep(sd) do {} while (0)
-
-static inline bool sysfs_ignore_lockdep(struct sysfs_dirent *sd)
-{
- return true;
-}
-
-#endif
-
/*
* Context structure to be used while adding/removing nodes.
*/
diff --git a/include/linux/kernfs.h b/include/linux/kernfs.h
index 53cf787..9db44f2 100644
--- a/include/linux/kernfs.h
+++ b/include/linux/kernfs.h
@@ -11,6 +11,7 @@
#include <linux/err.h>
#include <linux/list.h>
#include <linux/mutex.h>
+#include <linux/lockdep.h>
struct file;
struct iattr;
@@ -62,6 +63,10 @@ struct kernfs_ops {
loff_t off);
int (*mmap)(struct sysfs_open_file *of, struct vm_area_struct *vma);
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+ struct lock_class_key lockdep_key;
+#endif
};
#ifdef CONFIG_SYSFS
@@ -69,11 +74,12 @@ struct kernfs_ops {
struct sysfs_dirent *kernfs_create_dir_ns(struct sysfs_dirent *parent,
const char *name, void *priv,
const void *ns);
-struct sysfs_dirent *kernfs_create_file_ns(struct sysfs_dirent *parent,
- const char *name,
- umode_t mode, loff_t size,
- const struct kernfs_ops *ops,
- void *priv, const void *ns);
+struct sysfs_dirent *kernfs_create_file_ns_key(struct sysfs_dirent *parent,
+ const char *name,
+ umode_t mode, loff_t size,
+ const struct kernfs_ops *ops,
+ void *priv, const void *ns,
+ struct lock_class_key *key);
struct sysfs_dirent *kernfs_create_link(struct sysfs_dirent *parent,
const char *name,
struct sysfs_dirent *target);
@@ -93,9 +99,10 @@ kernfs_create_dir_ns(struct sysfs_dirent *parent, const char *name, void *priv,
{ return ERR_PTR(-ENOSYS); }
static inline struct sysfs_dirent *
-kernfs_create_file_ns(struct sysfs_dirent *parent, const char *name,
- umode_t mode, loff_t size, const struct kernfs_ops *ops,
- void *priv, const void *ns)
+kernfs_create_file_ns_key(struct sysfs_dirent *parent, const char *name,
+ umode_t mode, loff_t size,
+ const struct kernfs_ops *ops, void *priv,
+ const void *ns, struct lock_class_key *key)
{ return ERR_PTR(-ENOSYS); }
static inline struct sysfs_dirent *
@@ -129,6 +136,20 @@ kernfs_create_dir(struct sysfs_dirent *parent, const char *name, void *priv)
}
static inline struct sysfs_dirent *
+kernfs_create_file_ns(struct sysfs_dirent *parent, const char *name,
+ umode_t mode, loff_t size, const struct kernfs_ops *ops,
+ void *priv, const void *ns)
+{
+ struct lock_class_key *key = NULL;
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+ key = (struct lock_class_key *)&ops->lockdep_key;
+#endif
+ return kernfs_create_file_ns_key(parent, name, mode, size, ops, priv,
+ ns, key);
+}
+
+static inline struct sysfs_dirent *
kernfs_create_file(struct sysfs_dirent *parent, const char *name, umode_t mode,
loff_t size, const struct kernfs_ops *ops, void *priv)
{
--
1.8.3.1
next prev parent reply other threads:[~2013-11-03 9:59 UTC|newest]
Thread overview: 40+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-11-03 9:52 [PATCHSET driver-core-next] sysfs: separate out kernfs, take #2 Tejun Heo
2013-11-03 9:52 ` [PATCH 01/39] sysfs: make __sysfs_add_one() fail if the parent isn't a directory Tejun Heo
2013-11-03 9:52 ` [PATCH 02/39] sysfs, kernfs: add skeletons for kernfs Tejun Heo
2013-11-03 9:52 ` [PATCH 03/39] sysfs, kernfs: introduce kernfs_remove[_by_name[_ns]]() Tejun Heo
2013-11-03 9:52 ` [PATCH 04/39] sysfs, kernfs: introduce kernfs_create_link() Tejun Heo
2013-11-03 9:52 ` [PATCH 05/39] sysfs, kernfs: introduce kernfs_rename[_ns]() Tejun Heo
2013-11-03 9:52 ` [PATCH 06/39] sysfs, kernfs: introduce kernfs_setattr() Tejun Heo
2013-11-03 9:52 ` [PATCH 07/39] sysfs, kernfs: replace sysfs_dirent->s_dir.kobj and ->s_attr.[bin_]attr with ->priv Tejun Heo
2013-11-03 9:52 ` [PATCH 08/39] sysfs, kernfs: introduce kernfs_create_dir[_ns]() Tejun Heo
2013-11-03 9:52 ` [PATCH 09/39] sysfs, kernfs: prepare read path for kernfs Tejun Heo
2013-11-03 9:52 ` [PATCH 10/39] sysfs, kernfs: prepare write " Tejun Heo
2013-11-03 9:52 ` [PATCH 11/39] sysfs, kernfs: prepare mmap " Tejun Heo
2013-11-03 9:52 ` [PATCH 12/39] sysfs, kernfs: prepare open, release, poll paths " Tejun Heo
2013-11-03 9:52 ` [PATCH 13/39] sysfs, kernfs: move sysfs_open_file to include/linux/kernfs.h Tejun Heo
2013-11-03 9:52 ` [PATCH 14/39] sysfs, kernfs: introduce kernfs_ops Tejun Heo
2013-11-03 9:52 ` [PATCH 15/39] sysfs, kernfs: add sysfs_dirent->s_attr.size Tejun Heo
2013-11-03 9:52 ` [PATCH 16/39] sysfs, kernfs: remove SYSFS_KOBJ_BIN_ATTR Tejun Heo
2013-11-03 9:52 ` [PATCH 17/39] sysfs, kernfs: introduce kernfs_create_file[_ns]() Tejun Heo
2013-11-03 9:52 ` [PATCH 18/39] sysfs, kernfs: remove sysfs_add_one() Tejun Heo
2013-11-03 9:52 ` [PATCH 19/39] sysfs, kernfs: add kernfs_ops->seq_{start|next|stop}() Tejun Heo
2013-11-03 9:52 ` [PATCH 20/39] sysfs, kernfs: introduce kernfs_notify() Tejun Heo
2013-11-03 9:53 ` [PATCH 21/39] sysfs, kernfs: reorganize SYSFS_* constants Tejun Heo
2013-11-03 9:53 ` Tejun Heo [this message]
2013-11-03 9:53 ` [PATCH 23/39] sysfs, kernfs: introduce kernfs[_find_and]_get() and kernfs_put() Tejun Heo
2013-11-03 9:53 ` [PATCH 24/39] sysfs, kernfs: move internal decls to fs/kernfs/kernfs-internal.h Tejun Heo
2013-11-03 9:53 ` [PATCH 25/39] sysfs, kernfs: move inode code to fs/kernfs/inode.c Tejun Heo
2013-11-03 9:53 ` [PATCH 26/39] sysfs, kernfs: move dir core code to fs/kernfs/dir.c Tejun Heo
2013-11-03 9:53 ` [PATCH 27/39] sysfs, kernfs: move file core code to fs/kernfs/file.c Tejun Heo
2013-11-03 9:53 ` [PATCH 28/39] sysfs, kernfs: move symlink core code to fs/kernfs/symlink.c Tejun Heo
2013-11-03 9:53 ` [PATCH 29/39] sysfs, kernfs: drop unused params from sysfs_fill_super() Tejun Heo
2013-11-03 9:53 ` [PATCH 30/39] sysfs, kernfs: make sysfs_super_info->ns const Tejun Heo
2013-11-03 9:53 ` [PATCH 31/39] sysfs, kernfs: no need to kern_mount() sysfs from sysfs_init() Tejun Heo
2013-11-03 9:53 ` [PATCH 32/39] sysfs, kernfs: introduce sysfs_root_sd Tejun Heo
2013-11-03 9:53 ` [PATCH 33/39] sysfs, kernfs: implement kernfs_create/destroy_root() Tejun Heo
2013-11-03 9:53 ` [PATCH 34/39] sysfs, kernfs: make inode number ida per kernfs_root Tejun Heo
2013-11-03 9:53 ` [PATCH 35/39] sysfs, kernfs: make super_blocks bind to different kernfs_roots Tejun Heo
2013-11-03 9:53 ` [PATCH 36/39] sysfs, kernfs: prepare mount path for kernfs Tejun Heo
2013-11-03 9:53 ` [PATCH 37/39] sysfs, kernfs: move mount core code to fs/kernfs/mount.c Tejun Heo
2013-11-03 9:53 ` [PATCH 38/39] sysfs, kernfs: make sysfs_dirent definition public Tejun Heo
2013-11-03 9:53 ` [PATCH 39/39] sysfs, kernfs: remove cross inclusions of internal headers Tejun Heo
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