Merge getxattr prototype change into work.lookups

The rest of work.xattr stuff isn't needed for this branch

3 files changed, 48 insertions, 9 deletions

diff --git a/fs/nfs/direct.c b/fs/nfs/direct.c
index c93826e4a8c6..438d4e70742f 100644
--- a/fs/nfs/direct.c
+++ b/fs/nfs/direct.c
@@ -396,7 +396,7 @@ static void nfs_direct_complete(struct nfs_direct_req *dreq, bool write)
 static void nfs_direct_readpage_release(struct nfs_page *req)
 {
 	dprintk("NFS: direct read done (%s/%llu %d@%lld)\n",
-		d_inode(req->wb_context->dentry)->i_sb->s_id,
+		req->wb_context->dentry->d_sb->s_id,
 		(unsigned long long)NFS_FILEID(d_inode(req->wb_context->dentry)),
 		req->wb_bytes,
 		(long long)req_offset(req));
diff --git a/fs/nfs/nfs3acl.c b/fs/nfs/nfs3acl.c
index 17c0fa1eccfa..720d92f5abfb 100644
--- a/fs/nfs/nfs3acl.c
+++ b/fs/nfs/nfs3acl.c
@@ -11,6 +11,38 @@
 
 #define NFSDBG_FACILITY	NFSDBG_PROC
 
+/*
+ * nfs3_prepare_get_acl, nfs3_complete_get_acl, nfs3_abort_get_acl: Helpers for
+ * caching get_acl results in a race-free way.  See fs/posix_acl.c:get_acl()
+ * for explanations.
+ */
+static void nfs3_prepare_get_acl(struct posix_acl **p)
+{
+	struct posix_acl *sentinel = uncached_acl_sentinel(current);
+
+	if (cmpxchg(p, ACL_NOT_CACHED, sentinel) != ACL_NOT_CACHED) {
+		/* Not the first reader or sentinel already in place. */
+	}
+}
+
+static void nfs3_complete_get_acl(struct posix_acl **p, struct posix_acl *acl)
+{
+	struct posix_acl *sentinel = uncached_acl_sentinel(current);
+
+	/* Only cache the ACL if our sentinel is still in place. */
+	posix_acl_dup(acl);
+	if (cmpxchg(p, sentinel, acl) != sentinel)
+		posix_acl_release(acl);
+}
+
+static void nfs3_abort_get_acl(struct posix_acl **p)
+{
+	struct posix_acl *sentinel = uncached_acl_sentinel(current);
+
+	/* Remove our sentinel upon failure. */
+	cmpxchg(p, sentinel, ACL_NOT_CACHED);
+}
+
 struct posix_acl *nfs3_get_acl(struct inode *inode, int type)
 {
 	struct nfs_server *server = NFS_SERVER(inode);
@@ -55,6 +87,11 @@ struct posix_acl *nfs3_get_acl(struct inode *inode, int type)
 	if (res.fattr == NULL)
 		return ERR_PTR(-ENOMEM);
 
+	if (args.mask & NFS_ACL)
+		nfs3_prepare_get_acl(&inode->i_acl);
+	if (args.mask & NFS_DFACL)
+		nfs3_prepare_get_acl(&inode->i_default_acl);
+
 	status = rpc_call_sync(server->client_acl, &msg, 0);
 	dprintk("NFS reply getacl: %d\n", status);
 
@@ -89,12 +126,12 @@ struct posix_acl *nfs3_get_acl(struct inode *inode, int type)
 	}
 
 	if (res.mask & NFS_ACL)
-		set_cached_acl(inode, ACL_TYPE_ACCESS, res.acl_access);
+		nfs3_complete_get_acl(&inode->i_acl, res.acl_access);
 	else
 		forget_cached_acl(inode, ACL_TYPE_ACCESS);
 
 	if (res.mask & NFS_DFACL)
-		set_cached_acl(inode, ACL_TYPE_DEFAULT, res.acl_default);
+		nfs3_complete_get_acl(&inode->i_default_acl, res.acl_default);
 	else
 		forget_cached_acl(inode, ACL_TYPE_DEFAULT);
 
@@ -108,6 +145,8 @@ struct posix_acl *nfs3_get_acl(struct inode *inode, int type)
 	}
 
 getout:
+	nfs3_abort_get_acl(&inode->i_acl);
+	nfs3_abort_get_acl(&inode->i_default_acl);
 	posix_acl_release(res.acl_access);
 	posix_acl_release(res.acl_default);
 	nfs_free_fattr(res.fattr);
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 327b8c34d360..7a7ac1dafa02 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -6263,10 +6263,10 @@ static int nfs4_xattr_set_nfs4_acl(const struct xattr_handler *handler,
 }
 
 static int nfs4_xattr_get_nfs4_acl(const struct xattr_handler *handler,
-				   struct dentry *dentry, const char *key,
-				   void *buf, size_t buflen)
+				   struct dentry *unused, struct inode *inode,
+				   const char *key, void *buf, size_t buflen)
 {
-	return nfs4_proc_get_acl(d_inode(dentry), buf, buflen);
+	return nfs4_proc_get_acl(inode, buf, buflen);
 }
 
 static bool nfs4_xattr_list_nfs4_acl(struct dentry *dentry)
@@ -6288,11 +6288,11 @@ static int nfs4_xattr_set_nfs4_label(const struct xattr_handler *handler,
 }
 
 static int nfs4_xattr_get_nfs4_label(const struct xattr_handler *handler,
-				     struct dentry *dentry, const char *key,
-				     void *buf, size_t buflen)
+				     struct dentry *unused, struct inode *inode,
+				     const char *key, void *buf, size_t buflen)
 {
 	if (security_ismaclabel(key))
-		return nfs4_get_security_label(d_inode(dentry), buf, buflen);
+		return nfs4_get_security_label(inode, buf, buflen);
 	return -EOPNOTSUPP;
 }