[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-Id: <20240315-dir-deleg-v1-6-a1d6209a3654@kernel.org>
Date: Fri, 15 Mar 2024 12:52:57 -0400
From: Jeff Layton <jlayton@...nel.org>
To: Alexander Viro <viro@...iv.linux.org.uk>,
Christian Brauner <brauner@...nel.org>, Jan Kara <jack@...e.cz>,
Chuck Lever <chuck.lever@...cle.com>,
Alexander Aring <alex.aring@...il.com>,
Trond Myklebust <trond.myklebust@...merspace.com>,
Anna Schumaker <anna@...nel.org>, Steve French <sfrench@...ba.org>,
Paulo Alcantara <pc@...guebit.com>,
Ronnie Sahlberg <ronniesahlberg@...il.com>,
Shyam Prasad N <sprasad@...rosoft.com>, Tom Talpey <tom@...pey.com>,
Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
"Rafael J. Wysocki" <rafael@...nel.org>,
David Howells <dhowells@...hat.com>, Tyler Hicks <code@...icks.com>,
Neil Brown <neilb@...e.de>, Olga Kornievskaia <kolga@...app.com>,
Dai Ngo <Dai.Ngo@...cle.com>, Miklos Szeredi <miklos@...redi.hu>,
Amir Goldstein <amir73il@...il.com>, Namjae Jeon <linkinjeon@...nel.org>,
Sergey Senozhatsky <senozhatsky@...omium.org>,
"David S. Miller" <davem@...emloft.net>, Eric Dumazet <edumazet@...gle.com>,
Jakub Kicinski <kuba@...nel.org>, Paolo Abeni <pabeni@...hat.com>
Cc: linux-fsdevel@...r.kernel.org, linux-kernel@...r.kernel.org,
linux-nfs@...r.kernel.org, linux-cifs@...r.kernel.org,
samba-technical@...ts.samba.org, netfs@...ts.linux.dev,
ecryptfs@...r.kernel.org, linux-unionfs@...r.kernel.org,
netdev@...r.kernel.org, Jeff Layton <jlayton@...nel.org>
Subject: [PATCH RFC 06/24] vfs: break parent dir delegations in open(...,
O_CREAT) codepath
In order to add directory delegation support, we need to break
delegations on the parent whenever there is going to be a change in the
directory.
Add a delegated_inode parameter to lookup_open and have it break the
delegation. Then, open_last_lookups can wait for the delegation break
and retry the call to lookup_open once it's done.
Signed-off-by: Jeff Layton <jlayton@...nel.org>
---
fs/namei.c | 22 ++++++++++++++++++----
1 file changed, 18 insertions(+), 4 deletions(-)
diff --git a/fs/namei.c b/fs/namei.c
index f00d8d708001..88598a62ec64 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -3404,7 +3404,7 @@ static struct dentry *atomic_open(struct nameidata *nd, struct dentry *dentry,
*/
static struct dentry *lookup_open(struct nameidata *nd, struct file *file,
const struct open_flags *op,
- bool got_write)
+ bool got_write, struct inode **delegated_inode)
{
struct mnt_idmap *idmap;
struct dentry *dir = nd->path.dentry;
@@ -3490,6 +3490,11 @@ static struct dentry *lookup_open(struct nameidata *nd, struct file *file,
/* Negative dentry, just create the file */
if (!dentry->d_inode && (open_flag & O_CREAT)) {
+ /* but break the directory lease first! */
+ error = try_break_deleg(dir_inode, delegated_inode);
+ if (error)
+ goto out_dput;
+
file->f_mode |= FMODE_CREATED;
audit_inode_child(dir_inode, dentry, AUDIT_TYPE_CHILD_CREATE);
if (!dir_inode->i_op->create) {
@@ -3517,6 +3522,7 @@ static const char *open_last_lookups(struct nameidata *nd,
struct file *file, const struct open_flags *op)
{
struct dentry *dir = nd->path.dentry;
+ struct inode *delegated_inode = NULL;
int open_flag = op->open_flag;
bool got_write = false;
struct dentry *dentry;
@@ -3553,7 +3559,7 @@ static const char *open_last_lookups(struct nameidata *nd,
if (unlikely(nd->last.name[nd->last.len]))
return ERR_PTR(-EISDIR);
}
-
+retry:
if (open_flag & (O_CREAT | O_TRUNC | O_WRONLY | O_RDWR)) {
got_write = !mnt_want_write(nd->path.mnt);
/*
@@ -3566,7 +3572,7 @@ static const char *open_last_lookups(struct nameidata *nd,
inode_lock(dir->d_inode);
else
inode_lock_shared(dir->d_inode);
- dentry = lookup_open(nd, file, op, got_write);
+ dentry = lookup_open(nd, file, op, got_write, &delegated_inode);
if (!IS_ERR(dentry) && (file->f_mode & FMODE_CREATED))
fsnotify_create(dir->d_inode, dentry);
if (open_flag & O_CREAT)
@@ -3577,8 +3583,16 @@ static const char *open_last_lookups(struct nameidata *nd,
if (got_write)
mnt_drop_write(nd->path.mnt);
- if (IS_ERR(dentry))
+ if (IS_ERR(dentry)) {
+ if (delegated_inode) {
+ int error = break_deleg_wait(&delegated_inode);
+
+ if (!error)
+ goto retry;
+ return ERR_PTR(error);
+ }
return ERR_CAST(dentry);
+ }
if (file->f_mode & (FMODE_OPENED | FMODE_CREATED)) {
dput(nd->path.dentry);
--
2.44.0
Powered by blists - more mailing lists