Return-Path: Received: from mx1.redhat.com ([209.132.183.28]:38630 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933090AbdEKOAk (ORCPT ); Thu, 11 May 2017 10:00:40 -0400 Subject: [PATCH 05/14] VFS: Provide empty name qstr [ver #2] From: David Howells To: mszeredi@redhat.com, viro@zeniv.linux.org.uk, jlayton@redhat.com Cc: dhowells@redhat.com, linux-fsdevel@vger.kernel.org, linux-nfs@vger.kernel.org, linux-kernel@vger.kernel.org Date: Thu, 11 May 2017 15:00:35 +0100 Message-ID: <149451123585.4599.6856406693086176310.stgit@warthog.procyon.org.uk> In-Reply-To: <149451118535.4599.16084557087363834548.stgit@warthog.procyon.org.uk> References: <149451118535.4599.16084557087363834548.stgit@warthog.procyon.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Sender: linux-nfs-owner@vger.kernel.org List-ID: Provide an empty name (ie. "") qstr for general use. Signed-off-by: David Howells --- fs/dcache.c | 8 ++++++-- fs/gfs2/dir.c | 3 +-- fs/namei.c | 3 +-- fs/nsfs.c | 3 +-- fs/pipe.c | 3 +-- include/linux/dcache.h | 5 +++++ 6 files changed, 15 insertions(+), 10 deletions(-) diff --git a/fs/dcache.c b/fs/dcache.c index 95d71eda8142..9a17ee020996 100644 --- a/fs/dcache.c +++ b/fs/dcache.c @@ -90,6 +90,11 @@ EXPORT_SYMBOL(rename_lock); static struct kmem_cache *dentry_cache __read_mostly; +const struct qstr empty_name = QSTR_INIT("", 0); +EXPORT_SYMBOL(empty_name); +const struct qstr slash_name = QSTR_INIT("/", 1); +EXPORT_SYMBOL(slash_name); + /* * This is the single most critical data structure when it comes * to the dcache: the hashtable for lookups. Somebody should try @@ -1580,8 +1585,7 @@ struct dentry *__d_alloc(struct super_block *sb, const struct qstr *name) */ dentry->d_iname[DNAME_INLINE_LEN-1] = 0; if (unlikely(!name)) { - static const struct qstr anon = QSTR_INIT("/", 1); - name = &anon; + name = &slash_name; dname = dentry->d_iname; } else if (name->len > DNAME_INLINE_LEN-1) { size_t size = offsetof(struct external_name, name[1]); diff --git a/fs/gfs2/dir.c b/fs/gfs2/dir.c index 79113219be5f..a5dfff6a033e 100644 --- a/fs/gfs2/dir.c +++ b/fs/gfs2/dir.c @@ -872,7 +872,6 @@ static struct gfs2_leaf *new_leaf(struct inode *inode, struct buffer_head **pbh, struct buffer_head *bh; struct gfs2_leaf *leaf; struct gfs2_dirent *dent; - struct qstr name = { .name = "" }; struct timespec tv = current_time(inode); error = gfs2_alloc_blocks(ip, &bn, &n, 0, NULL); @@ -896,7 +895,7 @@ static struct gfs2_leaf *new_leaf(struct inode *inode, struct buffer_head **pbh, leaf->lf_sec = cpu_to_be64(tv.tv_sec); memset(leaf->lf_reserved2, 0, sizeof(leaf->lf_reserved2)); dent = (struct gfs2_dirent *)(leaf+1); - gfs2_qstr2dirent(&name, bh->b_size - sizeof(struct gfs2_leaf), dent); + gfs2_qstr2dirent(&empty_name, bh->b_size - sizeof(struct gfs2_leaf), dent); *pbh = bh; return leaf; } diff --git a/fs/namei.c b/fs/namei.c index 19dcf62133cc..0c2af2c7794f 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -3368,7 +3368,6 @@ static int do_last(struct nameidata *nd, struct dentry *vfs_tmpfile(struct dentry *dentry, umode_t mode, int open_flag) { - static const struct qstr name = QSTR_INIT("/", 1); struct dentry *child = NULL; struct inode *dir = dentry->d_inode; struct inode *inode; @@ -3382,7 +3381,7 @@ struct dentry *vfs_tmpfile(struct dentry *dentry, umode_t mode, int open_flag) if (!dir->i_op->tmpfile) goto out_err; error = -ENOMEM; - child = d_alloc(dentry, &name); + child = d_alloc(dentry, &slash_name); if (unlikely(!child)) goto out_err; error = dir->i_op->tmpfile(dir, child, mode); diff --git a/fs/nsfs.c b/fs/nsfs.c index 323f492e0822..253cf59b27a1 100644 --- a/fs/nsfs.c +++ b/fs/nsfs.c @@ -53,7 +53,6 @@ static void nsfs_evict(struct inode *inode) static void *__ns_get_path(struct path *path, struct ns_common *ns) { struct vfsmount *mnt = nsfs_mnt; - struct qstr qname = { .name = "", }; struct dentry *dentry; struct inode *inode; unsigned long d; @@ -85,7 +84,7 @@ static void *__ns_get_path(struct path *path, struct ns_common *ns) inode->i_fop = &ns_file_operations; inode->i_private = ns; - dentry = d_alloc_pseudo(mnt->mnt_sb, &qname); + dentry = d_alloc_pseudo(mnt->mnt_sb, &empty_name); if (!dentry) { iput(inode); return ERR_PTR(-ENOMEM); diff --git a/fs/pipe.c b/fs/pipe.c index 73b84baf58f8..97e5be897753 100644 --- a/fs/pipe.c +++ b/fs/pipe.c @@ -739,13 +739,12 @@ int create_pipe_files(struct file **res, int flags) struct inode *inode = get_pipe_inode(); struct file *f; struct path path; - static struct qstr name = { .name = "" }; if (!inode) return -ENFILE; err = -ENOMEM; - path.dentry = d_alloc_pseudo(pipe_mnt->mnt_sb, &name); + path.dentry = d_alloc_pseudo(pipe_mnt->mnt_sb, &empty_name); if (!path.dentry) goto err_inode; path.mnt = mntget(pipe_mnt); diff --git a/include/linux/dcache.h b/include/linux/dcache.h index d2e38dc6172c..3f65a4fa72ed 100644 --- a/include/linux/dcache.h +++ b/include/linux/dcache.h @@ -55,6 +55,11 @@ struct qstr { #define QSTR_INIT(n,l) { { { .len = l } }, .name = n } +extern const char empty_string[]; +extern const struct qstr empty_name; +extern const char slash_string[]; +extern const struct qstr slash_name; + struct dentry_stat_t { long nr_dentry; long nr_unused;