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From: ebiederm-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org (Eric W. Biederman)
To: Greg KH <greg-U8xfFu+wG4EAvxtiuMwx3w@public.gmane.org>
Cc: Tejun Heo <htejun-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>,
	gregkh-l3A5Bk7waGM@public.gmane.org,
	linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org,
	Linux Containers
	<containers-qjLDD68F18O7TbgM5vRIOg@public.gmane.org>,
	stern-nwvwT67g6+6dFdvTe/nMLpVzexx5G7lz@public.gmane.org,
	satyam-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org,
	cornelia.huck-tA70FqPdS9bQT0dZR+AlfA@public.gmane.org
Subject: [PATCH 09/25] sysfs: Move sysfs_get_dentry below __sysfs_get_dentry
Date: Tue, 07 Aug 2007 15:17:33 -0600	[thread overview]
Message-ID: <m13ayvjb82.fsf_-_@ebiederm.dsl.xmission.com> (raw)
In-Reply-To: <m17io7jba4.fsf_-_-T1Yj925okcoyDheHMi7gv2pdwda3JcWeAL8bYrjMMd8@public.gmane.org> (Eric W. Biederman's message of "Tue, 07 Aug 2007 15:16:19 -0600")


sysfs_get_dentry is higher in fs/sysfs/dir.c then is needed and it the
dependencies get simpler if we move it down in the file to where I
have placed __sysfs_get_dentry.  So this patch just moves
sysfs_get_dentry so code movement doesn't get confused with later code
changes. 

Signed-off-by: Eric W. Biederman <ebiederm-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org>
---
 fs/sysfs/dir.c |  196 ++++++++++++++++++++++++++++----------------------------
 1 files changed, 98 insertions(+), 98 deletions(-)

diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c
index 2caa5e0..59a9ce8 100644
--- a/fs/sysfs/dir.c
+++ b/fs/sysfs/dir.c
@@ -73,104 +73,6 @@ static void sysfs_unlink_sibling(struct sysfs_dirent *sd)
 }
 
 /**
- *	sysfs_get_dentry - get dentry for the given sysfs_dirent
- *	@sd: sysfs_dirent of interest
- *
- *	Get dentry for @sd.  Dentry is looked up if currently not
- *	present.  This function climbs sysfs_dirent tree till it
- *	reaches a sysfs_dirent with valid dentry attached and descends
- *	down from there looking up dentry for each step.
- *
- *	LOCKING:
- *	Kernel thread context (may sleep)
- *
- *	RETURNS:
- *	Pointer to found dentry on success, ERR_PTR() value on error.
- */
-struct dentry *sysfs_get_dentry(struct sysfs_dirent *sd)
-{
-	struct sysfs_dirent *cur;
-	struct dentry *parent_dentry, *dentry;
-	int i, depth;
-
-	/* Find the first parent which has valid s_dentry and get the
-	 * dentry.
-	 */
-	mutex_lock(&sysfs_mutex);
- restart0:
-	spin_lock(&sysfs_assoc_lock);
- restart1:
-	spin_lock(&dcache_lock);
-
-	dentry = NULL;
-	depth = 0;
-	cur = sd;
-	while (!cur->s_dentry || !cur->s_dentry->d_inode) {
-		if (cur->s_flags & SYSFS_FLAG_REMOVED) {
-			dentry = ERR_PTR(-ENOENT);
-			depth = 0;
-			break;
-		}
-		cur = cur->s_parent;
-		depth++;
-	}
-	if (!IS_ERR(dentry))
-		dentry = dget_locked(cur->s_dentry);
-
-	spin_unlock(&dcache_lock);
-	spin_unlock(&sysfs_assoc_lock);
-
-	/* from the found dentry, look up depth times */
-	while (depth--) {
-		/* find and get depth'th ancestor */
-		for (cur = sd, i = 0; cur && i < depth; i++)
-			cur = cur->s_parent;
-
-		/* This can happen if tree structure was modified due
-		 * to move/rename.  Restart.
-		 */
-		if (i != depth) {
-			dput(dentry);
-			goto restart0;
-		}
-
-		sysfs_get(cur);
-
-		mutex_unlock(&sysfs_mutex);
-
-		/* look it up */
-		parent_dentry = dentry;
-		dentry = lookup_one_len_kern(cur->s_name, parent_dentry,
-					     strlen(cur->s_name));
-		dput(parent_dentry);
-
-		if (IS_ERR(dentry)) {
-			sysfs_put(cur);
-			return dentry;
-		}
-
-		mutex_lock(&sysfs_mutex);
-		spin_lock(&sysfs_assoc_lock);
-
-		/* This, again, can happen if tree structure has
-		 * changed and we looked up the wrong thing.  Restart.
-		 */
-		if (cur->s_dentry != dentry) {
-			dput(dentry);
-			sysfs_put(cur);
-			goto restart1;
-		}
-
-		spin_unlock(&sysfs_assoc_lock);
-
-		sysfs_put(cur);
-	}
-
-	mutex_unlock(&sysfs_mutex);
-	return dentry;
-}
-
-/**
  *	sysfs_get_active - get an active reference to sysfs_dirent
  *	@sd: sysfs_dirent to get an active reference to
  *
@@ -886,6 +788,104 @@ static struct dentry *__sysfs_get_dentry(struct super_block *sb, struct sysfs_di
 	return dentry;
 }
 
+/**
+ *	sysfs_get_dentry - get dentry for the given sysfs_dirent
+ *	@sd: sysfs_dirent of interest
+ *
+ *	Get dentry for @sd.  Dentry is looked up if currently not
+ *	present.  This function climbs sysfs_dirent tree till it
+ *	reaches a sysfs_dirent with valid dentry attached and descends
+ *	down from there looking up dentry for each step.
+ *
+ *	LOCKING:
+ *	Kernel thread context (may sleep)
+ *
+ *	RETURNS:
+ *	Pointer to found dentry on success, ERR_PTR() value on error.
+ */
+struct dentry *sysfs_get_dentry(struct sysfs_dirent *sd)
+{
+	struct sysfs_dirent *cur;
+	struct dentry *parent_dentry, *dentry;
+	int i, depth;
+
+	/* Find the first parent which has valid s_dentry and get the
+	 * dentry.
+	 */
+	mutex_lock(&sysfs_mutex);
+ restart0:
+	spin_lock(&sysfs_assoc_lock);
+ restart1:
+	spin_lock(&dcache_lock);
+
+	dentry = NULL;
+	depth = 0;
+	cur = sd;
+	while (!cur->s_dentry || !cur->s_dentry->d_inode) {
+		if (cur->s_flags & SYSFS_FLAG_REMOVED) {
+			dentry = ERR_PTR(-ENOENT);
+			depth = 0;
+			break;
+		}
+		cur = cur->s_parent;
+		depth++;
+	}
+	if (!IS_ERR(dentry))
+		dentry = dget_locked(cur->s_dentry);
+
+	spin_unlock(&dcache_lock);
+	spin_unlock(&sysfs_assoc_lock);
+
+	/* from the found dentry, look up depth times */
+	while (depth--) {
+		/* find and get depth'th ancestor */
+		for (cur = sd, i = 0; cur && i < depth; i++)
+			cur = cur->s_parent;
+
+		/* This can happen if tree structure was modified due
+		 * to move/rename.  Restart.
+		 */
+		if (i != depth) {
+			dput(dentry);
+			goto restart0;
+		}
+
+		sysfs_get(cur);
+
+		mutex_unlock(&sysfs_mutex);
+
+		/* look it up */
+		parent_dentry = dentry;
+		dentry = lookup_one_len_kern(cur->s_name, parent_dentry,
+					     strlen(cur->s_name));
+		dput(parent_dentry);
+
+		if (IS_ERR(dentry)) {
+			sysfs_put(cur);
+			return dentry;
+		}
+
+		mutex_lock(&sysfs_mutex);
+		spin_lock(&sysfs_assoc_lock);
+
+		/* This, again, can happen if tree structure has
+		 * changed and we looked up the wrong thing.  Restart.
+		 */
+		if (cur->s_dentry != dentry) {
+			dput(dentry);
+			sysfs_put(cur);
+			goto restart1;
+		}
+
+		spin_unlock(&sysfs_assoc_lock);
+
+		sysfs_put(cur);
+	}
+
+	mutex_unlock(&sysfs_mutex);
+	return dentry;
+}
+
 int sysfs_rename_dir(struct kobject * kobj, const char *new_name)
 {
 	struct sysfs_dirent *sd;
-- 
1.5.1.1.181.g2de0

  parent reply	other threads:[~2007-08-07 21:17 UTC|newest]

Thread overview: 79+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <11860582832964-git-send-email-htejun@gmail.com>
     [not found] ` <11860582832964-git-send-email-htejun-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
2007-08-07 21:06   ` [PATCH 0/25] Sysfs cleanups & tagged directory support Eric W. Biederman
     [not found]     ` <m1643rkqb6.fsf-T1Yj925okcoyDheHMi7gv2pdwda3JcWeAL8bYrjMMd8@public.gmane.org>
2007-08-07 21:08       ` [PATCH 01/25] sysfs: Move all of inode initialization into sysfs_init_inode Eric W. Biederman
     [not found]         ` <m11wefkq88.fsf_-_-T1Yj925okcoyDheHMi7gv2pdwda3JcWeAL8bYrjMMd8@public.gmane.org>
2007-08-07 21:08           ` [PATCH 02/25] sysfs: Remove sysfs_instantiate Eric W. Biederman
     [not found]             ` <m1wsw7jbml.fsf_-_-T1Yj925okcoyDheHMi7gv2pdwda3JcWeAL8bYrjMMd8@public.gmane.org>
2007-08-07 21:10               ` [PATCH 03/25] sysfs: Use kill_anon_super Eric W. Biederman
     [not found]                 ` <m1sl6vjbjw.fsf_-_-T1Yj925okcoyDheHMi7gv2pdwda3JcWeAL8bYrjMMd8@public.gmane.org>
2007-08-07 21:11                   ` [PATCH 04/25] sysfs: Make sysfs_mount static Eric W. Biederman
     [not found]                     ` <m1odhjjbij.fsf_-_-T1Yj925okcoyDheHMi7gv2pdwda3JcWeAL8bYrjMMd8@public.gmane.org>
2007-08-07 21:12                       ` [PATCH 05/25] sysfs: In sysfs_lookup don't open code sysfs_find_dirent Eric W. Biederman
     [not found]                         ` <m1k5s7jbh9.fsf_-_-T1Yj925okcoyDheHMi7gv2pdwda3JcWeAL8bYrjMMd8@public.gmane.org>
2007-08-07 21:13                           ` [PATCH 06/25] sysfs: Simplify readdir Eric W. Biederman
     [not found]                             ` <m1fy2vjbf9.fsf_-_-T1Yj925okcoyDheHMi7gv2pdwda3JcWeAL8bYrjMMd8@public.gmane.org>
2007-08-07 21:14                               ` [PATCH 07/25] sysfs: Rewrite sysfs_drop_dentry Eric W. Biederman
     [not found]                                 ` <m1bqdjjbcf.fsf_-_-T1Yj925okcoyDheHMi7gv2pdwda3JcWeAL8bYrjMMd8@public.gmane.org>
2007-08-07 21:16                                   ` [PATCH 08/25] sysfs: Implement __sysfs_get_dentry Eric W. Biederman
     [not found]                                     ` <m17io7jba4.fsf_-_-T1Yj925okcoyDheHMi7gv2pdwda3JcWeAL8bYrjMMd8@public.gmane.org>
2007-08-07 21:17                                       ` Eric W. Biederman [this message]
     [not found]                                         ` <m13ayvjb82.fsf_-_-T1Yj925okcoyDheHMi7gv2pdwda3JcWeAL8bYrjMMd8@public.gmane.org>
2007-08-07 21:18                                           ` [PATCH 10/25] sysfs: Rewrite sysfs_get_dentry in terms of __sysfs_get_dentry Eric W. Biederman
     [not found]                                             ` <m1y7gnhwm4.fsf_-_-T1Yj925okcoyDheHMi7gv2pdwda3JcWeAL8bYrjMMd8@public.gmane.org>
2007-08-07 21:19                                               ` [PATCH 11/25] sysfs: Remove s_dentry Eric W. Biederman
     [not found]                                                 ` <m1tzrbhwkc.fsf_-_-T1Yj925okcoyDheHMi7gv2pdwda3JcWeAL8bYrjMMd8@public.gmane.org>
2007-08-07 21:21                                                   ` [PATCH 12/25] sysfs: Introduce sysfs_rename_mutex Eric W. Biederman
     [not found]                                                     ` <m1ps1zhwhp.fsf_-_-T1Yj925okcoyDheHMi7gv2pdwda3JcWeAL8bYrjMMd8@public.gmane.org>
2007-08-07 21:22                                                       ` [PATCH 13/25] sysfs: Simply sysfs_get_dentry Eric W. Biederman
     [not found]                                                         ` <m1lkcnhwfu.fsf_-_-T1Yj925okcoyDheHMi7gv2pdwda3JcWeAL8bYrjMMd8@public.gmane.org>
2007-08-07 21:23                                                           ` [PATCH 14/25] sysfs: Don't use lookup_one_len_kern Eric W. Biederman
     [not found]                                                             ` <m1hcnbhwcy.fsf_-_-T1Yj925okcoyDheHMi7gv2pdwda3JcWeAL8bYrjMMd8@public.gmane.org>
2007-08-07 21:25                                                               ` [PATCH 15/25] vfs: Remove lookup_one_len_kern Eric W. Biederman
     [not found]                                                                 ` <m1d4xzhwb2.fsf_-_-T1Yj925okcoyDheHMi7gv2pdwda3JcWeAL8bYrjMMd8@public.gmane.org>
2007-08-07 21:26                                                                   ` [PATCH 16/25] sysfs: Support for preventing unmounts Eric W. Biederman
     [not found]                                                                     ` <m18x8nhw8r.fsf_-_-T1Yj925okcoyDheHMi7gv2pdwda3JcWeAL8bYrjMMd8@public.gmane.org>
2007-08-07 21:27                                                                       ` [PATCH 17/25] sysfs: Rewrite rename in terms of sysfs dirents Eric W. Biederman
     [not found]                                                                         ` <m14pjbhw6y.fsf_-_-T1Yj925okcoyDheHMi7gv2pdwda3JcWeAL8bYrjMMd8@public.gmane.org>
2007-08-07 21:28                                                                           ` [PATCH 18/25] sysfs: Rewrite sysfs_move_dir " Eric W. Biederman
     [not found]                                                                             ` <m1zm13ghlh.fsf_-_-T1Yj925okcoyDheHMi7gv2pdwda3JcWeAL8bYrjMMd8@public.gmane.org>
2007-08-07 21:29                                                                               ` [PATCH 19/25] sysfs: sysfs_get_dentry add a sb parameter Eric W. Biederman
     [not found]                                                                                 ` <m1vebrghjg.fsf_-_-T1Yj925okcoyDheHMi7gv2pdwda3JcWeAL8bYrjMMd8@public.gmane.org>
2007-08-07 21:31                                                                                   ` [PATCH 20/25] sysfs: Rename Support multiple superblocks Eric W. Biederman
     [not found]                                                                                     ` <m1r6mfghg9.fsf_-_-T1Yj925okcoyDheHMi7gv2pdwda3JcWeAL8bYrjMMd8@public.gmane.org>
2007-08-07 21:32                                                                                       ` [PATCH 21/25] sysfs: sysfs_chmod_file handle " Eric W. Biederman
     [not found]                                                                                         ` <m1myx3ghdt.fsf_-_-T1Yj925okcoyDheHMi7gv2pdwda3JcWeAL8bYrjMMd8@public.gmane.org>
2007-08-07 21:34                                                                                           ` [PATCH 22/25] sysfs: sysfs_uptdate_file " Eric W. Biederman
     [not found]                                                                                             ` <m1ir7rghbg.fsf_-_-T1Yj925okcoyDheHMi7gv2pdwda3JcWeAL8bYrjMMd8@public.gmane.org>
2007-08-07 21:35                                                                                               ` [PATCH 23/25] sysfs: Implement sysfs tagged directory support Eric W. Biederman
     [not found]                                                                                                 ` <m1ejifgh98.fsf_-_-T1Yj925okcoyDheHMi7gv2pdwda3JcWeAL8bYrjMMd8@public.gmane.org>
2007-08-07 21:36                                                                                                   ` [PATCH 24/25] sysfs: Implement sysfs_delete_link and sysfs_rename_link Eric W. Biederman
     [not found]                                                                                                     ` <m1abt3gh86.fsf_-_-T1Yj925okcoyDheHMi7gv2pdwda3JcWeAL8bYrjMMd8@public.gmane.org>
2007-08-07 21:36                                                                                                       ` [PATCH 25/25] driver core: Implement tagged directory support for device classes Eric W. Biederman
2007-08-08 16:31                                                                                                 ` alternative approached at tagged nodes Tejun Heo
2007-08-08  9:39                                                                                             ` [PATCH 22/25] sysfs: sysfs_uptdate_file handle multiple superblocks Tejun Heo
2007-08-08  9:38                                                                                         ` [PATCH 21/25] sysfs: sysfs_chmod_file " Tejun Heo
2007-08-08  9:35                                                                                     ` [PATCH 20/25] sysfs: Rename Support " Tejun Heo
2007-08-08 15:45                                                                                       ` Eric W. Biederman
2007-08-08 15:50                                                                                         ` Tejun Heo
     [not found]                                                                                           ` <46B9E660.6030702-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
2007-08-08 16:35                                                                                             ` Eric W. Biederman
2007-08-08 16:42                                                                                               ` Tejun Heo
2007-08-08 16:55                                                                                                 ` Eric W. Biederman
2007-08-08  8:57                                                                                 ` [PATCH 19/25] sysfs: sysfs_get_dentry add a sb parameter Tejun Heo
2007-08-08 15:34                                                                                   ` Eric W. Biederman
2007-08-08  8:53                                                                             ` [PATCH 18/25] sysfs: Rewrite sysfs_move_dir in terms of sysfs dirents Tejun Heo
2007-08-08  8:51                                                                         ` [PATCH 17/25] sysfs: Rewrite rename " Tejun Heo
2007-08-08 15:32                                                                           ` Eric W. Biederman
2007-08-08  8:39                                                                 ` [PATCH 15/25] vfs: Remove lookup_one_len_kern Tejun Heo
2007-08-08  8:38                                                             ` [PATCH 14/25] sysfs: Don't use lookup_one_len_kern Tejun Heo
2007-08-08 15:26                                                               ` Eric W. Biederman
2007-08-08 15:35                                                                 ` Tejun Heo
2007-08-08  8:24                                                         ` [PATCH 13/25] sysfs: Simply sysfs_get_dentry Tejun Heo
2007-08-08  8:19                                                     ` [PATCH 12/25] sysfs: Introduce sysfs_rename_mutex Tejun Heo
2007-08-08  8:23                                                       ` Tejun Heo
2007-08-08  8:28                                                       ` Eric W. Biederman
2007-08-08  7:46                                                 ` [PATCH 11/25] sysfs: Remove s_dentry Tejun Heo
2007-08-08  7:45                                             ` [PATCH 10/25] sysfs: Rewrite sysfs_get_dentry in terms of __sysfs_get_dentry Tejun Heo
2007-08-08  7:45                                         ` [PATCH 09/25] sysfs: Move sysfs_get_dentry below __sysfs_get_dentry Tejun Heo
2007-08-08  7:45                                     ` [PATCH 08/25] sysfs: Implement __sysfs_get_dentry Tejun Heo
2007-08-08  7:35                                   ` [PATCH 07/25] sysfs: Rewrite sysfs_drop_dentry Tejun Heo
2007-08-08  7:12                             ` [PATCH 06/25] sysfs: Simplify readdir Tejun Heo
2007-08-08  6:51                         ` [PATCH 05/25] sysfs: In sysfs_lookup don't open code sysfs_find_dirent Tejun Heo
2007-08-08  6:51                     ` [PATCH 04/25] sysfs: Make sysfs_mount static Tejun Heo
2007-08-08  6:50                 ` [PATCH 03/25] sysfs: Use kill_anon_super Tejun Heo
2007-08-08  6:37             ` [PATCH 02/25] sysfs: Remove sysfs_instantiate Tejun Heo
2007-08-08  6:37         ` [PATCH 01/25] sysfs: Move all of inode initialization into sysfs_init_inode Tejun Heo
2007-08-08  7:38       ` [PATCH 0/25] Sysfs cleanups & tagged directory support Cornelia Huck
2007-08-08  7:47         ` Eric W. Biederman
2007-08-08  7:53           ` Tejun Heo
2007-08-08  7:54           ` Cornelia Huck
2007-08-08  7:57             ` Eric W. Biederman
2007-08-08  8:37               ` Cornelia Huck
2007-08-08  8:54                 ` Tejun Heo
2007-08-08  9:16                   ` Cornelia Huck
2007-08-08 14:16                 ` Cornelia Huck
2007-08-08 14:35                   ` Tejun Heo
2007-08-08 14:50                     ` Cornelia Huck
2007-08-08 14:55                       ` Tejun Heo
2007-08-08 15:08                         ` Eric W. Biederman
2007-08-08 15:13                           ` Tejun Heo
2007-08-08 15:16                             ` Tejun Heo
     [not found]                               ` <46B9DE5E.7050406-l3A5Bk7waGM@public.gmane.org>
2007-08-08 15:53                                 ` Eric W. Biederman
2007-08-08 16:03                                   ` Tejun Heo
     [not found]                                     ` <46B9E948.8080605-l3A5Bk7waGM@public.gmane.org>
2007-08-08 16:37                                       ` Eric W. Biederman
2007-08-08 15:15                         ` Cornelia Huck
2007-08-08 16:35                       ` Cornelia Huck

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