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Date: Mon, 1 Jul 2013 10:33:09 +0100
From: Steven Whitehouse <swhiteho@...hat.com>
To: linux-kernel@...r.kernel.org, cluster-devel@...hat.com
Cc: Steven Whitehouse <swhiteho@...hat.com>
Subject: [PATCH 06/12] GFS2: Only do one directory search on create
Creation of a new inode requires a directory search in order to ensure
that we are not trying to create an inode with the same name as an
existing one. This was hidden away inside the create_ok() function.
In the case that there was an existing inode, and a lookup can be
substituted for a create (which is the case with regular files
when the O_EXCL flag is not in use) then we were doing a second
lookup in order to return the inode.
This patch merges these two lookups into one. This can be done by
passing a flag to gfs2_dir_search() to tell it to just return -EEXIST
in the cases where we don't actually want to look up the inode.
Signed-off-by: Steven Whitehouse <swhiteho@...hat.com>
diff --git a/fs/gfs2/dir.c b/fs/gfs2/dir.c
index b631c90..f0c7052 100644
--- a/fs/gfs2/dir.c
+++ b/fs/gfs2/dir.c
@@ -1555,9 +1555,9 @@ out:
/**
* gfs2_dir_search - Search a directory
- * @dip: The GFS2 inode
- * @filename:
- * @inode:
+ * @dip: The GFS2 dir inode
+ * @name: The name we are looking up
+ * @fail_on_exist: Fail if the name exists rather than looking it up
*
* This routine searches a directory for a file or another directory.
* Assumes a glock is held on dip.
@@ -1565,22 +1565,25 @@ out:
* Returns: errno
*/
-struct inode *gfs2_dir_search(struct inode *dir, const struct qstr *name)
+struct inode *gfs2_dir_search(struct inode *dir, const struct qstr *name,
+ bool fail_on_exist)
{
struct buffer_head *bh;
struct gfs2_dirent *dent;
- struct inode *inode;
+ u64 addr, formal_ino;
+ u16 dtype;
dent = gfs2_dirent_search(dir, name, gfs2_dirent_find, &bh);
if (dent) {
if (IS_ERR(dent))
return ERR_CAST(dent);
- inode = gfs2_inode_lookup(dir->i_sb,
- be16_to_cpu(dent->de_type),
- be64_to_cpu(dent->de_inum.no_addr),
- be64_to_cpu(dent->de_inum.no_formal_ino), 0);
+ dtype = be16_to_cpu(dent->de_type);
+ addr = be64_to_cpu(dent->de_inum.no_addr);
+ formal_ino = be64_to_cpu(dent->de_inum.no_formal_ino);
brelse(bh);
- return inode;
+ if (fail_on_exist)
+ return ERR_PTR(-EEXIST);
+ return gfs2_inode_lookup(dir->i_sb, dtype, addr, formal_ino, 0);
}
return ERR_PTR(-ENOENT);
}
diff --git a/fs/gfs2/dir.h b/fs/gfs2/dir.h
index 98c960b..d3f2738 100644
--- a/fs/gfs2/dir.h
+++ b/fs/gfs2/dir.h
@@ -18,7 +18,8 @@ struct gfs2_inode;
struct gfs2_inum;
extern struct inode *gfs2_dir_search(struct inode *dir,
- const struct qstr *filename);
+ const struct qstr *filename,
+ bool fail_on_exist);
extern int gfs2_dir_check(struct inode *dir, const struct qstr *filename,
const struct gfs2_inode *ip);
extern int gfs2_dir_add(struct inode *inode, const struct qstr *filename,
diff --git a/fs/gfs2/inode.c b/fs/gfs2/inode.c
index 5fbb8df..ede16ae 100644
--- a/fs/gfs2/inode.c
+++ b/fs/gfs2/inode.c
@@ -313,7 +313,7 @@ struct inode *gfs2_lookupi(struct inode *dir, const struct qstr *name,
goto out;
}
- inode = gfs2_dir_search(dir, name);
+ inode = gfs2_dir_search(dir, name, false);
if (IS_ERR(inode))
error = PTR_ERR(inode);
out:
@@ -346,17 +346,6 @@ static int create_ok(struct gfs2_inode *dip, const struct qstr *name,
if (!dip->i_inode.i_nlink)
return -ENOENT;
- error = gfs2_dir_check(&dip->i_inode, name, NULL);
- switch (error) {
- case -ENOENT:
- error = 0;
- break;
- case 0:
- return -EEXIST;
- default:
- return error;
- }
-
if (dip->i_entries == (u32)-1)
return -EFBIG;
if (S_ISDIR(mode) && dip->i_inode.i_nlink == (u32)-1)
@@ -584,14 +573,18 @@ static int gfs2_create_inode(struct inode *dir, struct dentry *dentry,
goto fail;
error = create_ok(dip, name, mode);
- if ((error == -EEXIST) && S_ISREG(mode) && !excl) {
- inode = gfs2_lookupi(dir, &dentry->d_name, 0);
+ if (error)
+ goto fail_gunlock;
+
+ inode = gfs2_dir_search(dir, &dentry->d_name, !S_ISREG(mode) || excl);
+ error = PTR_ERR(inode);
+ if (!IS_ERR(inode)) {
gfs2_glock_dq_uninit(ghs);
d_instantiate(dentry, inode);
- return PTR_RET(inode);
- }
- if (error)
+ return 0;
+ } else if (error != -ENOENT) {
goto fail_gunlock;
+ }
arq = error = gfs2_diradd_alloc_required(dir, name);
if (error < 0)
--
1.7.4
--
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