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author | Steven Whitehouse <swhiteho@redhat.com> | 2013-06-11 12:45:29 (GMT) |
---|---|---|
committer | Steven Whitehouse <swhiteho@redhat.com> | 2013-06-11 12:45:29 (GMT) |
commit | 5a00f3cc978be45b9d2597851bedaa40630bc597 (patch) | |
tree | 716a1b29594e352c4c793b699331d4d57578cce9 /fs/gfs2 | |
parent | a9aefd707c65aa5a7945b3f16bd39f314aa8414d (diff) | |
download | linux-5a00f3cc978be45b9d2597851bedaa40630bc597.tar.xz |
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@redhat.com>
Diffstat (limited to 'fs/gfs2')
-rw-r--r-- | fs/gfs2/dir.c | 23 | ||||
-rw-r--r-- | fs/gfs2/dir.h | 3 | ||||
-rw-r--r-- | fs/gfs2/inode.c | 27 |
3 files changed, 25 insertions, 28 deletions
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..ede16ae7 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) |