From 4c6974f51a981d14f13e36049d6307d3bcda550e Mon Sep 17 00:00:00 2001
From: "Eric W. Biederman" <ebiederm@xmission.com>
Date: Sat, 7 Nov 2009 23:27:02 -0800
Subject: sysfs: Simplify sysfs_chmod_file semantics

Currently every caller of sysfs_chmod_file happens at either
file creation time to set a non-default mode or in response
to a specific user requested space change in policy.  Making
timestamps of when the chmod happens and notification of
a file changing mode uninteresting.

Remove the unnecessary time stamp and filesystem change
notification, and removes the last of the explicit inotify
and donitfy support from sysfs.

Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---
 fs/sysfs/file.c | 10 +---------
 1 file changed, 1 insertion(+), 9 deletions(-)

(limited to 'fs/sysfs/file.c')

diff --git a/fs/sysfs/file.c b/fs/sysfs/file.c
index f5ea4680f15f..faa1a803caa9 100644
--- a/fs/sysfs/file.c
+++ b/fs/sysfs/file.c
@@ -604,17 +604,9 @@ int sysfs_chmod_file(struct kobject *kobj, struct attribute *attr, mode_t mode)
 	mutex_lock(&inode->i_mutex);
 
 	newattrs.ia_mode = (mode & S_IALLUGO) | (inode->i_mode & ~S_IALLUGO);
-	newattrs.ia_valid = ATTR_MODE | ATTR_CTIME;
-	newattrs.ia_ctime = current_fs_time(inode->i_sb);
+	newattrs.ia_valid = ATTR_MODE;
 	rc = sysfs_setattr(victim, &newattrs);
 
-	if (rc == 0) {
-		fsnotify_change(victim, newattrs.ia_valid);
-		mutex_lock(&sysfs_mutex);
-		victim_sd->s_mode = newattrs.ia_mode;
-		mutex_unlock(&sysfs_mutex);
-	}
-
 	mutex_unlock(&inode->i_mutex);
  out:
 	dput(victim);
-- 
cgit v1.2.3


From 06fc0d66f7ed3a3b08e8fcf8c325ecf0b8f93fea Mon Sep 17 00:00:00 2001
From: "Eric W. Biederman" <ebiederm@xmission.com>
Date: Fri, 20 Nov 2009 16:08:54 -0800
Subject: sysfs: In sysfs_chmod_file lazily propagate the mode change.

Now that sysfs_getattr and sysfs_permission refresh the vfs
inode there is no need to immediatly push the mode change
into the vfs cache.  Reducing the amount of work needed and
simplifying the locking.

Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---
 fs/sysfs/file.c | 31 ++++++++-----------------------
 1 file changed, 8 insertions(+), 23 deletions(-)

(limited to 'fs/sysfs/file.c')

diff --git a/fs/sysfs/file.c b/fs/sysfs/file.c
index faa1a803caa9..dc30d9e31683 100644
--- a/fs/sysfs/file.c
+++ b/fs/sysfs/file.c
@@ -579,38 +579,23 @@ EXPORT_SYMBOL_GPL(sysfs_add_file_to_group);
  */
 int sysfs_chmod_file(struct kobject *kobj, struct attribute *attr, mode_t mode)
 {
-	struct sysfs_dirent *victim_sd = NULL;
-	struct dentry *victim = NULL;
-	struct inode * inode;
+	struct sysfs_dirent *sd;
 	struct iattr newattrs;
 	int rc;
 
-	rc = -ENOENT;
-	victim_sd = sysfs_get_dirent(kobj->sd, attr->name);
-	if (!victim_sd)
-		goto out;
+	mutex_lock(&sysfs_mutex);
 
-	mutex_lock(&sysfs_rename_mutex);
-	victim = sysfs_get_dentry(victim_sd);
-	mutex_unlock(&sysfs_rename_mutex);
-	if (IS_ERR(victim)) {
-		rc = PTR_ERR(victim);
-		victim = NULL;
+	rc = -ENOENT;
+	sd = sysfs_find_dirent(kobj->sd, attr->name);
+	if (!sd)
 		goto out;
-	}
-
-	inode = victim->d_inode;
 
-	mutex_lock(&inode->i_mutex);
-
-	newattrs.ia_mode = (mode & S_IALLUGO) | (inode->i_mode & ~S_IALLUGO);
+	newattrs.ia_mode = (mode & S_IALLUGO) | (sd->s_mode & ~S_IALLUGO);
 	newattrs.ia_valid = ATTR_MODE;
-	rc = sysfs_setattr(victim, &newattrs);
+	rc = sysfs_sd_setattr(sd, &newattrs);
 
-	mutex_unlock(&inode->i_mutex);
  out:
-	dput(victim);
-	sysfs_put(victim_sd);
+	mutex_unlock(&sysfs_mutex);
 	return rc;
 }
 EXPORT_SYMBOL_GPL(sysfs_chmod_file);
-- 
cgit v1.2.3