[PATCH 0/6] Remove struct nameidata from lower level NFS code

[PATCH 0/6] Remove struct nameidata from lower level NFS code

[Trond Myklebust]

Hi,

The following patches attempt to clean up the atomic open code so that we
keep all the functions that depend on the struct nameidata in fs/nfs/dir.c.
Instead of passing down the struct nameidata, we have the lower layer NFSv4
code fill in the nfs_open_context, which can then be used by nfs_atomic_lookup
to fill in the struct file.

Cheers
  Trond

Trond Myklebust (6):
  NFSv4: Clean up nfs4_atomic_open
  NFSv4: Further minor cleanups for nfs4_atomic_open()
  NFSv4: Clean up nfs4_open_revalidate
  NFSv4: Further cleanups for nfs4_open_revalidate()
  NFS: Clean up nfs4_proc_create()
  NFS: Add an 'open_context' element to struct nfs_rpc_ops

 fs/nfs/dir.c            |  179 ++++++++++++++++++++++++++++++++++++++++++----
 fs/nfs/inode.c          |    8 +-
 fs/nfs/nfs3proc.c       |    2 +-
 fs/nfs/nfs4_fs.h        |    2 -
 fs/nfs/nfs4proc.c       |  148 ++++++---------------------------------
 fs/nfs/proc.c           |    2 +-
 include/linux/nfs_fs.h  |    2 +
 include/linux/nfs_xdr.h |    6 ++-
 8 files changed, 198 insertions(+), 151 deletions(-)

-- 
1.7.2.3

[PATCH 1/6] NFSv4: Clean up nfs4_atomic_open

[Trond Myklebust]

Start moving the 'struct nameidata' dependent code out of the lower level
NFS code in preparation for the removal of open intents.

Instead of the struct nameidata, we pass down a partially initialised
struct nfs_open_context that will be fully initialised by the atomic open
upon success.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
---
 fs/nfs/dir.c           |   77 ++++++++++++++++++++++++++++++++++++++++++++++-
 fs/nfs/inode.c         |    8 ++--
 fs/nfs/nfs4_fs.h       |    2 +-
 fs/nfs/nfs4proc.c      |   40 +++++++------------------
 include/linux/nfs_fs.h |    2 +
 5 files changed, 93 insertions(+), 36 deletions(-)

diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index e257172..17529b5 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -38,6 +38,7 @@
 #include "delegation.h"
 #include "iostat.h"
 #include "internal.h"
+#include "fscache.h"
 
 /* #define NFS_DEBUG_VERBOSE 1 */
 
@@ -1029,9 +1030,61 @@ static int is_atomic_open(struct nameidata *nd)
 	return 1;
 }
 
+static struct nfs_open_context *nameidata_to_nfs_open_context(struct dentry *dentry, struct nameidata *nd)
+{
+	struct path path = {
+		.mnt = nd->path.mnt,
+		.dentry = dentry,
+	};
+	struct nfs_open_context *ctx;
+	struct rpc_cred *cred;
+	fmode_t fmode = nd->intent.open.flags & (FMODE_READ | FMODE_WRITE | FMODE_EXEC);
+
+	cred = rpc_lookup_cred();
+	if (IS_ERR(cred))
+		return ERR_CAST(cred);
+	ctx = alloc_nfs_open_context(&path, cred, fmode);
+	put_rpccred(cred);
+	if (ctx == NULL)
+		return ERR_PTR(-ENOMEM);
+	return ctx;
+}
+
+static int do_open(struct inode *inode, struct file *filp)
+{
+	nfs_fscache_set_inode_cookie(inode, filp);
+	return 0;
+}
+
+static int nfs_intent_set_file(struct nameidata *nd, struct nfs_open_context *ctx)
+{
+	struct file *filp;
+	int ret = 0;
+
+	/* If the open_intent is for execute, we have an extra check to make */
+	if (ctx->mode & FMODE_EXEC) {
+		ret = nfs_may_open(ctx->path.dentry->d_inode,
+				ctx->cred,
+				nd->intent.open.flags);
+		if (ret < 0)
+			goto out;
+	}
+	filp = lookup_instantiate_filp(nd, ctx->path.dentry, do_open);
+	if (IS_ERR(filp))
+		ret = PTR_ERR(filp);
+	else
+		nfs_file_set_open_context(filp, ctx);
+out:
+	put_nfs_open_context(ctx);
+	return ret;
+}
+
 static struct dentry *nfs_atomic_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd)
 {
+	struct nfs_open_context *ctx;
+	struct iattr attr;
 	struct dentry *res = NULL;
+	int open_flags;
 	int error;
 
 	dfprintk(VFS, "NFS: atomic_lookup(%s/%ld), %s\n",
@@ -1054,9 +1107,27 @@ static struct dentry *nfs_atomic_lookup(struct inode *dir, struct dentry *dentry
 		goto out;
 	}
 
+	ctx = nameidata_to_nfs_open_context(dentry, nd);
+	res = ERR_CAST(ctx);
+	if (IS_ERR(ctx))
+		goto out;
+
+	open_flags = nd->intent.open.flags;
+	if (nd->flags & LOOKUP_CREATE) {
+		attr.ia_mode = nd->intent.open.create_mode;
+		attr.ia_valid = ATTR_MODE;
+		if (!IS_POSIXACL(dir))
+			attr.ia_mode &= ~current_umask();
+	} else {
+		open_flags &= ~O_EXCL;
+		attr.ia_valid = 0;
+		BUG_ON(open_flags & O_CREAT);
+	}
+
 	/* Open the file on the server */
-	res = nfs4_atomic_open(dir, dentry, nd);
+	res = nfs4_atomic_open(dir, ctx, open_flags, &attr);
 	if (IS_ERR(res)) {
+		put_nfs_open_context(ctx);
 		error = PTR_ERR(res);
 		switch (error) {
 			/* Make a negative dentry */
@@ -1074,8 +1145,10 @@ static struct dentry *nfs_atomic_lookup(struct inode *dir, struct dentry *dentry
 			default:
 				goto out;
 		}
-	} else if (res != NULL)
+	}
+	if (res != NULL)
 		dentry = res;
+	nfs_intent_set_file(nd, ctx);
 out:
 	return res;
 no_open:
diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index 7d2d6c7..2f92664 100644
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -623,7 +623,7 @@ void nfs_close_context(struct nfs_open_context *ctx, int is_sync)
 	nfs_revalidate_inode(server, inode);
 }
 
-static struct nfs_open_context *alloc_nfs_open_context(struct path *path, struct rpc_cred *cred)
+struct nfs_open_context *alloc_nfs_open_context(struct path *path, struct rpc_cred *cred, fmode_t f_mode)
 {
 	struct nfs_open_context *ctx;
 
@@ -633,6 +633,7 @@ static struct nfs_open_context *alloc_nfs_open_context(struct path *path, struct
 		path_get(&ctx->path);
 		ctx->cred = get_rpccred(cred);
 		ctx->state = NULL;
+		ctx->mode = f_mode;
 		ctx->flags = 0;
 		ctx->error = 0;
 		ctx->dir_cookie = 0;
@@ -673,7 +674,7 @@ void put_nfs_open_context(struct nfs_open_context *ctx)
  * Ensure that mmap has a recent RPC credential for use when writing out
  * shared pages
  */
-static void nfs_file_set_open_context(struct file *filp, struct nfs_open_context *ctx)
+void nfs_file_set_open_context(struct file *filp, struct nfs_open_context *ctx)
 {
 	struct inode *inode = filp->f_path.dentry->d_inode;
 	struct nfs_inode *nfsi = NFS_I(inode);
@@ -730,11 +731,10 @@ int nfs_open(struct inode *inode, struct file *filp)
 	cred = rpc_lookup_cred();
 	if (IS_ERR(cred))
 		return PTR_ERR(cred);
-	ctx = alloc_nfs_open_context(&filp->f_path, cred);
+	ctx = alloc_nfs_open_context(&filp->f_path, cred, filp->f_mode);
 	put_rpccred(cred);
 	if (ctx == NULL)
 		return -ENOMEM;
-	ctx->mode = filp->f_mode;
 	nfs_file_set_open_context(filp, ctx);
 	put_nfs_open_context(ctx);
 	nfs_fscache_set_inode_cookie(inode, filp);
diff --git a/fs/nfs/nfs4_fs.h b/fs/nfs/nfs4_fs.h
index 311e15c..c5cc2a6 100644
--- a/fs/nfs/nfs4_fs.h
+++ b/fs/nfs/nfs4_fs.h
@@ -242,7 +242,7 @@ extern int nfs4_proc_renew(struct nfs_client *, struct rpc_cred *);
 extern int nfs4_init_clientid(struct nfs_client *, struct rpc_cred *);
 extern int nfs41_init_clientid(struct nfs_client *, struct rpc_cred *);
 extern int nfs4_do_close(struct path *path, struct nfs4_state *state, gfp_t gfp_mask, int wait);
-extern struct dentry *nfs4_atomic_open(struct inode *, struct dentry *, struct nameidata *);
+extern struct dentry *nfs4_atomic_open(struct inode *, struct nfs_open_context *, int, struct iattr *);
 extern int nfs4_open_revalidate(struct inode *, struct dentry *, int, struct nameidata *);
 extern int nfs4_server_capabilities(struct nfs_server *server, struct nfs_fh *fhandle);
 extern int nfs4_proc_fs_locations(struct inode *dir, const struct qstr *name,
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 089da5b..38c3bed 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -2025,39 +2025,17 @@ out_close:
 }
 
 struct dentry *
-nfs4_atomic_open(struct inode *dir, struct dentry *dentry, struct nameidata *nd)
+nfs4_atomic_open(struct inode *dir, struct nfs_open_context *ctx, int open_flags, struct iattr *attr)
 {
-	struct path path = {
-		.mnt = nd->path.mnt,
-		.dentry = dentry,
-	};
+	struct dentry *dentry = ctx->path.dentry;
 	struct dentry *parent;
-	struct iattr attr;
-	struct rpc_cred *cred;
 	struct nfs4_state *state;
 	struct dentry *res;
-	int open_flags = nd->intent.open.flags;
-	fmode_t fmode = open_flags & (FMODE_READ | FMODE_WRITE | FMODE_EXEC);
-
-	if (nd->flags & LOOKUP_CREATE) {
-		attr.ia_mode = nd->intent.open.create_mode;
-		attr.ia_valid = ATTR_MODE;
-		if (!IS_POSIXACL(dir))
-			attr.ia_mode &= ~current_umask();
-	} else {
-		open_flags &= ~O_EXCL;
-		attr.ia_valid = 0;
-		BUG_ON(open_flags & O_CREAT);
-	}
 
-	cred = rpc_lookup_cred();
-	if (IS_ERR(cred))
-		return (struct dentry *)cred;
 	parent = dentry->d_parent;
 	/* Protect against concurrent sillydeletes */
 	nfs_block_sillyrename(parent);
-	state = nfs4_do_open(dir, &path, fmode, open_flags, &attr, cred);
-	put_rpccred(cred);
+	state = nfs4_do_open(dir, &ctx->path, ctx->mode, open_flags, attr, ctx->cred);
 	if (IS_ERR(state)) {
 		if (PTR_ERR(state) == -ENOENT) {
 			d_add(dentry, NULL);
@@ -2067,11 +2045,15 @@ nfs4_atomic_open(struct inode *dir, struct dentry *dentry, struct nameidata *nd)
 		return (struct dentry *)state;
 	}
 	res = d_add_unique(dentry, igrab(state->inode));
-	if (res != NULL)
-		path.dentry = res;
-	nfs_set_verifier(path.dentry, nfs_save_change_attribute(dir));
+	if (res != NULL) {
+		struct dentry *dummy = ctx->path.dentry;
+
+		ctx->path.dentry = dget(res);
+		dput(dummy);
+	}
+	ctx->state = state;
+	nfs_set_verifier(ctx->path.dentry, nfs_save_change_attribute(dir));
 	nfs_unblock_sillyrename(parent);
-	nfs4_intent_set_file(nd, &path, state, fmode);
 	return res;
 }
 
diff --git a/include/linux/nfs_fs.h b/include/linux/nfs_fs.h
index 508f8cf..39cb70b 100644
--- a/include/linux/nfs_fs.h
+++ b/include/linux/nfs_fs.h
@@ -360,6 +360,8 @@ extern void nfs_setattr_update_inode(struct inode *inode, struct iattr *attr);
 extern struct nfs_open_context *get_nfs_open_context(struct nfs_open_context *ctx);
 extern void put_nfs_open_context(struct nfs_open_context *ctx);
 extern struct nfs_open_context *nfs_find_open_context(struct inode *inode, struct rpc_cred *cred, fmode_t mode);
+extern struct nfs_open_context *alloc_nfs_open_context(struct path *path, struct rpc_cred *cred, fmode_t f_mode);
+extern void nfs_file_set_open_context(struct file *filp, struct nfs_open_context *ctx);
 extern struct nfs_lock_context *nfs_get_lock_context(struct nfs_open_context *ctx);
 extern void nfs_put_lock_context(struct nfs_lock_context *l_ctx);
 extern u64 nfs_compat_user_ino64(u64 fileid);
-- 
1.7.2.3

[PATCH 2/6] NFSv4: Further minor cleanups for nfs4_atomic_open()

[Trond Myklebust]

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
---
 fs/nfs/dir.c      |   21 +++++++++++++++------
 fs/nfs/nfs4_fs.h  |    2 +-
 fs/nfs/nfs4proc.c |   28 ++++------------------------
 3 files changed, 20 insertions(+), 31 deletions(-)

diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index 17529b5..194676c 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -1084,8 +1084,8 @@ static struct dentry *nfs_atomic_lookup(struct inode *dir, struct dentry *dentry
 	struct nfs_open_context *ctx;
 	struct iattr attr;
 	struct dentry *res = NULL;
+	struct inode *inode;
 	int open_flags;
-	int error;
 
 	dfprintk(VFS, "NFS: atomic_lookup(%s/%ld), %s\n",
 			dir->i_sb->s_id, dir->i_ino, dentry->d_name.name);
@@ -1125,13 +1125,15 @@ static struct dentry *nfs_atomic_lookup(struct inode *dir, struct dentry *dentry
 	}
 
 	/* Open the file on the server */
-	res = nfs4_atomic_open(dir, ctx, open_flags, &attr);
-	if (IS_ERR(res)) {
+	nfs_block_sillyrename(dentry->d_parent);
+	inode = nfs4_atomic_open(dir, ctx, open_flags, &attr);
+	if (IS_ERR(inode)) {
+		nfs_unblock_sillyrename(dentry->d_parent);
 		put_nfs_open_context(ctx);
-		error = PTR_ERR(res);
-		switch (error) {
+		switch (PTR_ERR(inode)) {
 			/* Make a negative dentry */
 			case -ENOENT:
+				d_add(dentry, NULL);
 				res = NULL;
 				goto out;
 			/* This turned out not to be a regular file */
@@ -1143,13 +1145,20 @@ static struct dentry *nfs_atomic_lookup(struct inode *dir, struct dentry *dentry
 					goto no_open;
 			/* case -EINVAL: */
 			default:
+				res = ERR_CAST(inode);
 				goto out;
 		}
 	}
-	if (res != NULL)
+	res = d_add_unique(dentry, inode);
+	if (res != NULL) {
+		dput(ctx->path.dentry);
+		ctx->path.dentry = dget(res);
 		dentry = res;
+	}
 	nfs_intent_set_file(nd, ctx);
+	nfs_unblock_sillyrename(dentry->d_parent);
 out:
+	nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
 	return res;
 no_open:
 	return nfs_lookup(dir, dentry, nd);
diff --git a/fs/nfs/nfs4_fs.h b/fs/nfs/nfs4_fs.h
index c5cc2a6..8e1f639 100644
--- a/fs/nfs/nfs4_fs.h
+++ b/fs/nfs/nfs4_fs.h
@@ -242,7 +242,7 @@ extern int nfs4_proc_renew(struct nfs_client *, struct rpc_cred *);
 extern int nfs4_init_clientid(struct nfs_client *, struct rpc_cred *);
 extern int nfs41_init_clientid(struct nfs_client *, struct rpc_cred *);
 extern int nfs4_do_close(struct path *path, struct nfs4_state *state, gfp_t gfp_mask, int wait);
-extern struct dentry *nfs4_atomic_open(struct inode *, struct nfs_open_context *, int, struct iattr *);
+extern struct inode *nfs4_atomic_open(struct inode *, struct nfs_open_context *, int, struct iattr *);
 extern int nfs4_open_revalidate(struct inode *, struct dentry *, int, struct nameidata *);
 extern int nfs4_server_capabilities(struct nfs_server *server, struct nfs_fh *fhandle);
 extern int nfs4_proc_fs_locations(struct inode *dir, const struct qstr *name,
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 38c3bed..f8d41ee 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -2024,37 +2024,17 @@ out_close:
 	return ret;
 }
 
-struct dentry *
+struct inode *
 nfs4_atomic_open(struct inode *dir, struct nfs_open_context *ctx, int open_flags, struct iattr *attr)
 {
-	struct dentry *dentry = ctx->path.dentry;
-	struct dentry *parent;
 	struct nfs4_state *state;
-	struct dentry *res;
 
-	parent = dentry->d_parent;
 	/* Protect against concurrent sillydeletes */
-	nfs_block_sillyrename(parent);
 	state = nfs4_do_open(dir, &ctx->path, ctx->mode, open_flags, attr, ctx->cred);
-	if (IS_ERR(state)) {
-		if (PTR_ERR(state) == -ENOENT) {
-			d_add(dentry, NULL);
-			nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
-		}
-		nfs_unblock_sillyrename(parent);
-		return (struct dentry *)state;
-	}
-	res = d_add_unique(dentry, igrab(state->inode));
-	if (res != NULL) {
-		struct dentry *dummy = ctx->path.dentry;
-
-		ctx->path.dentry = dget(res);
-		dput(dummy);
-	}
+	if (IS_ERR(state))
+		return ERR_CAST(state);
 	ctx->state = state;
-	nfs_set_verifier(ctx->path.dentry, nfs_save_change_attribute(dir));
-	nfs_unblock_sillyrename(parent);
-	return res;
+	return igrab(state->inode);
 }
 
 int
-- 
1.7.2.3

[PATCH 3/6] NFSv4: Clean up nfs4_open_revalidate

[Trond Myklebust]

Remove references to 'struct nameidata' from the low-level open_revalidate
code, and replace them with a struct nfs_open_context which will be
correctly initialised upon success.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
---
 fs/nfs/dir.c      |   11 ++++++++++-
 fs/nfs/nfs4_fs.h  |    2 +-
 fs/nfs/nfs4proc.c |   23 ++++++-----------------
 3 files changed, 17 insertions(+), 19 deletions(-)

diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index 194676c..196775c 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -1169,6 +1169,7 @@ static int nfs_open_revalidate(struct dentry *dentry, struct nameidata *nd)
 	struct dentry *parent = NULL;
 	struct inode *inode = dentry->d_inode;
 	struct inode *dir;
+	struct nfs_open_context *ctx;
 	int openflags, ret = 0;
 
 	if (!is_atomic_open(nd) || d_mountpoint(dentry))
@@ -1194,12 +1195,20 @@ static int nfs_open_revalidate(struct dentry *dentry, struct nameidata *nd)
 	/* We can't create new files, or truncate existing ones here */
 	openflags &= ~(O_CREAT|O_EXCL|O_TRUNC);
 
+	ctx = nameidata_to_nfs_open_context(dentry, nd);
+	ret = PTR_ERR(ctx);
+	if (IS_ERR(ctx))
+		goto out;
 	/*
 	 * Note: we're not holding inode->i_mutex and so may be racing with
 	 * operations that change the directory. We therefore save the
 	 * change attribute *before* we do the RPC call.
 	 */
-	ret = nfs4_open_revalidate(dir, dentry, openflags, nd);
+	ret = nfs4_open_revalidate(dir, ctx, openflags);
+	if (ret == 1)
+		nfs_intent_set_file(nd, ctx);
+	else
+		put_nfs_open_context(ctx);
 out:
 	dput(parent);
 	if (!ret)
diff --git a/fs/nfs/nfs4_fs.h b/fs/nfs/nfs4_fs.h
index 8e1f639..76ec1c6 100644
--- a/fs/nfs/nfs4_fs.h
+++ b/fs/nfs/nfs4_fs.h
@@ -243,7 +243,7 @@ extern int nfs4_init_clientid(struct nfs_client *, struct rpc_cred *);
 extern int nfs41_init_clientid(struct nfs_client *, struct rpc_cred *);
 extern int nfs4_do_close(struct path *path, struct nfs4_state *state, gfp_t gfp_mask, int wait);
 extern struct inode *nfs4_atomic_open(struct inode *, struct nfs_open_context *, int, struct iattr *);
-extern int nfs4_open_revalidate(struct inode *, struct dentry *, int, struct nameidata *);
+extern int nfs4_open_revalidate(struct inode *, struct nfs_open_context *, int);
 extern int nfs4_server_capabilities(struct nfs_server *server, struct nfs_fh *fhandle);
 extern int nfs4_proc_fs_locations(struct inode *dir, const struct qstr *name,
 		struct nfs4_fs_locations *fs_locations, struct page *page);
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index f8d41ee..b476246 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -2038,21 +2038,11 @@ nfs4_atomic_open(struct inode *dir, struct nfs_open_context *ctx, int open_flags
 }
 
 int
-nfs4_open_revalidate(struct inode *dir, struct dentry *dentry, int openflags, struct nameidata *nd)
+nfs4_open_revalidate(struct inode *dir, struct nfs_open_context *ctx, int openflags)
 {
-	struct path path = {
-		.mnt = nd->path.mnt,
-		.dentry = dentry,
-	};
-	struct rpc_cred *cred;
 	struct nfs4_state *state;
-	fmode_t fmode = openflags & (FMODE_READ | FMODE_WRITE);
 
-	cred = rpc_lookup_cred();
-	if (IS_ERR(cred))
-		return PTR_ERR(cred);
-	state = nfs4_do_open(dir, &path, fmode, openflags, NULL, cred);
-	put_rpccred(cred);
+	state = nfs4_do_open(dir, &ctx->path, ctx->mode, openflags, NULL, ctx->cred);
 	if (IS_ERR(state)) {
 		switch (PTR_ERR(state)) {
 			case -EPERM:
@@ -2065,14 +2055,13 @@ nfs4_open_revalidate(struct inode *dir, struct dentry *dentry, int openflags, st
 				goto out_drop;
 		}
 	}
-	if (state->inode == dentry->d_inode) {
-		nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
-		nfs4_intent_set_file(nd, &path, state, fmode);
+	ctx->state = state;
+	if (state->inode == ctx->path.dentry->d_inode) {
+		nfs_set_verifier(ctx->path.dentry, nfs_save_change_attribute(dir));
 		return 1;
 	}
-	nfs4_close_sync(&path, state, fmode);
 out_drop:
-	d_drop(dentry);
+	d_drop(ctx->path.dentry);
 	return 0;
 }
 
-- 
1.7.2.3

[PATCH 4/6] NFSv4: Further cleanups for nfs4_open_revalidate()

[Trond Myklebust]

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
---
 fs/nfs/dir.c      |   32 ++++++++++++++++++++++++++------
 fs/nfs/nfs4_fs.h  |    1 -
 fs/nfs/nfs4proc.c |   28 ----------------------------
 3 files changed, 26 insertions(+), 35 deletions(-)

diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index 196775c..dc93d35 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -1204,16 +1204,36 @@ static int nfs_open_revalidate(struct dentry *dentry, struct nameidata *nd)
 	 * operations that change the directory. We therefore save the
 	 * change attribute *before* we do the RPC call.
 	 */
-	ret = nfs4_open_revalidate(dir, ctx, openflags);
-	if (ret == 1)
+	inode = nfs4_atomic_open(dir, ctx, openflags, NULL);
+	if (IS_ERR(inode)) {
+		ret = PTR_ERR(inode);
+		switch (ret) {
+		case -EPERM:
+		case -EACCES:
+		case -EDQUOT:
+		case -ENOSPC:
+		case -EROFS:
+			goto out_put_ctx;
+		default:
+			goto out_drop;
+		}
+	}
+	iput(inode);
+	if (inode == dentry->d_inode) {
+		nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
 		nfs_intent_set_file(nd, ctx);
-	else
-		put_nfs_open_context(ctx);
+	} else
+		goto out_drop;
 out:
 	dput(parent);
-	if (!ret)
-		d_drop(dentry);
 	return ret;
+out_drop:
+	d_drop(dentry);
+	ret = 0;
+out_put_ctx:
+	put_nfs_open_context(ctx);
+	goto out;
+
 no_open_dput:
 	dput(parent);
 no_open:
diff --git a/fs/nfs/nfs4_fs.h b/fs/nfs/nfs4_fs.h
index 76ec1c6..6cf12ba 100644
--- a/fs/nfs/nfs4_fs.h
+++ b/fs/nfs/nfs4_fs.h
@@ -243,7 +243,6 @@ extern int nfs4_init_clientid(struct nfs_client *, struct rpc_cred *);
 extern int nfs41_init_clientid(struct nfs_client *, struct rpc_cred *);
 extern int nfs4_do_close(struct path *path, struct nfs4_state *state, gfp_t gfp_mask, int wait);
 extern struct inode *nfs4_atomic_open(struct inode *, struct nfs_open_context *, int, struct iattr *);
-extern int nfs4_open_revalidate(struct inode *, struct nfs_open_context *, int);
 extern int nfs4_server_capabilities(struct nfs_server *server, struct nfs_fh *fhandle);
 extern int nfs4_proc_fs_locations(struct inode *dir, const struct qstr *name,
 		struct nfs4_fs_locations *fs_locations, struct page *page);
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index b476246..83c5ef6 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -2037,34 +2037,6 @@ nfs4_atomic_open(struct inode *dir, struct nfs_open_context *ctx, int open_flags
 	return igrab(state->inode);
 }
 
-int
-nfs4_open_revalidate(struct inode *dir, struct nfs_open_context *ctx, int openflags)
-{
-	struct nfs4_state *state;
-
-	state = nfs4_do_open(dir, &ctx->path, ctx->mode, openflags, NULL, ctx->cred);
-	if (IS_ERR(state)) {
-		switch (PTR_ERR(state)) {
-			case -EPERM:
-			case -EACCES:
-			case -EDQUOT:
-			case -ENOSPC:
-			case -EROFS:
-				return PTR_ERR(state);
-			default:
-				goto out_drop;
-		}
-	}
-	ctx->state = state;
-	if (state->inode == ctx->path.dentry->d_inode) {
-		nfs_set_verifier(ctx->path.dentry, nfs_save_change_attribute(dir));
-		return 1;
-	}
-out_drop:
-	d_drop(ctx->path.dentry);
-	return 0;
-}
-
 static void nfs4_close_context(struct nfs_open_context *ctx, int is_sync)
 {
 	if (ctx->state == NULL)
-- 
1.7.2.3

[PATCH 5/6] NFS: Clean up nfs4_proc_create()

[Trond Myklebust]

Remove all remaining references to the struct nameidata from the low level
NFS layers. Again pass down a partially initialised struct nfs_open_context
when we want to do atomic open+create.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
---
 fs/nfs/dir.c            |   47 ++++++++++++++++++++++++++++++++++-----
 fs/nfs/nfs3proc.c       |    2 +-
 fs/nfs/nfs4proc.c       |   56 +++++++++++-----------------------------------
 fs/nfs/proc.c           |    2 +-
 include/linux/nfs_xdr.h |    2 +-
 5 files changed, 58 insertions(+), 51 deletions(-)

diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index dc93d35..e37ffdd 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -105,8 +105,9 @@ const struct inode_operations nfs3_dir_inode_operations = {
 #ifdef CONFIG_NFS_V4
 
 static struct dentry *nfs_atomic_lookup(struct inode *, struct dentry *, struct nameidata *);
+static int nfs_open_create(struct inode *dir, struct dentry *dentry, int mode, struct nameidata *nd);
 const struct inode_operations nfs4_dir_inode_operations = {
-	.create		= nfs_create,
+	.create		= nfs_open_create,
 	.lookup		= nfs_atomic_lookup,
 	.link		= nfs_link,
 	.unlink		= nfs_unlink,
@@ -1239,6 +1240,44 @@ no_open_dput:
 no_open:
 	return nfs_lookup_revalidate(dentry, nd);
 }
+
+static int nfs_open_create(struct inode *dir, struct dentry *dentry, int mode,
+		struct nameidata *nd)
+{
+	struct nfs_open_context *ctx = NULL;
+	struct iattr attr;
+	int error;
+	int open_flags = 0;
+
+	dfprintk(VFS, "NFS: create(%s/%ld), %s\n",
+			dir->i_sb->s_id, dir->i_ino, dentry->d_name.name);
+
+	attr.ia_mode = mode;
+	attr.ia_valid = ATTR_MODE;
+
+	if ((nd->flags & LOOKUP_CREATE) != 0) {
+		open_flags = nd->intent.open.flags;
+
+		ctx = nameidata_to_nfs_open_context(dentry, nd);
+		error = PTR_ERR(ctx);
+		if (IS_ERR(ctx))
+			goto out_err;
+	}
+
+	error = NFS_PROTO(dir)->create(dir, dentry, &attr, open_flags, ctx);
+	if (error != 0)
+		goto out_put_ctx;
+	if (ctx != NULL)
+		nfs_intent_set_file(nd, ctx);
+	return 0;
+out_put_ctx:
+	if (ctx != NULL)
+		put_nfs_open_context(ctx);
+out_err:
+	d_drop(dentry);
+	return error;
+}
+
 #endif /* CONFIG_NFSV4 */
 
 static struct dentry *nfs_readdir_lookup(nfs_readdir_descriptor_t *desc)
@@ -1369,7 +1408,6 @@ static int nfs_create(struct inode *dir, struct dentry *dentry, int mode,
 {
 	struct iattr attr;
 	int error;
-	int open_flags = 0;
 
 	dfprintk(VFS, "NFS: create(%s/%ld), %s\n",
 			dir->i_sb->s_id, dir->i_ino, dentry->d_name.name);
@@ -1377,10 +1415,7 @@ static int nfs_create(struct inode *dir, struct dentry *dentry, int mode,
 	attr.ia_mode = mode;
 	attr.ia_valid = ATTR_MODE;
 
-	if ((nd->flags & LOOKUP_CREATE) != 0)
-		open_flags = nd->intent.open.flags;
-
-	error = NFS_PROTO(dir)->create(dir, dentry, &attr, open_flags, nd);
+	error = NFS_PROTO(dir)->create(dir, dentry, &attr, 0, NULL);
 	if (error != 0)
 		goto out_err;
 	return 0;
diff --git a/fs/nfs/nfs3proc.c b/fs/nfs/nfs3proc.c
index fabb4f2..2be4a7f 100644
--- a/fs/nfs/nfs3proc.c
+++ b/fs/nfs/nfs3proc.c
@@ -313,7 +313,7 @@ static void nfs3_free_createdata(struct nfs3_createdata *data)
  */
 static int
 nfs3_proc_create(struct inode *dir, struct dentry *dentry, struct iattr *sattr,
-		 int flags, struct nameidata *nd)
+		 int flags, struct nfs_open_context *ctx)
 {
 	struct nfs3_createdata *data;
 	mode_t mode = sattr->ia_mode;
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 83c5ef6..617b149 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -1998,32 +1998,6 @@ out:
 	return status;
 }
 
-static int nfs4_intent_set_file(struct nameidata *nd, struct path *path, struct nfs4_state *state, fmode_t fmode)
-{
-	struct file *filp;
-	int ret;
-
-	/* If the open_intent is for execute, we have an extra check to make */
-	if (fmode & FMODE_EXEC) {
-		ret = nfs_may_open(state->inode,
-				state->owner->so_cred,
-				nd->intent.open.flags);
-		if (ret < 0)
-			goto out_close;
-	}
-	filp = lookup_instantiate_filp(nd, path->dentry, NULL);
-	if (!IS_ERR(filp)) {
-		struct nfs_open_context *ctx;
-		ctx = nfs_file_open_context(filp);
-		ctx->state = state;
-		return 0;
-	}
-	ret = PTR_ERR(filp);
-out_close:
-	nfs4_close_sync(path, state, fmode & (FMODE_READ|FMODE_WRITE));
-	return ret;
-}
-
 struct inode *
 nfs4_atomic_open(struct inode *dir, struct nfs_open_context *ctx, int open_flags, struct iattr *attr)
 {
@@ -2491,36 +2465,34 @@ static int nfs4_proc_readlink(struct inode *inode, struct page *page,
 
 static int
 nfs4_proc_create(struct inode *dir, struct dentry *dentry, struct iattr *sattr,
-                 int flags, struct nameidata *nd)
+                 int flags, struct nfs_open_context *ctx)
 {
-	struct path path = {
-		.mnt = nd->path.mnt,
+	struct path my_path = {
 		.dentry = dentry,
 	};
+	struct path *path = &my_path;
 	struct nfs4_state *state;
-	struct rpc_cred *cred;
-	fmode_t fmode = flags & (FMODE_READ | FMODE_WRITE);
+	struct rpc_cred *cred = NULL;
+	fmode_t fmode = 0;
 	int status = 0;
 
-	cred = rpc_lookup_cred();
-	if (IS_ERR(cred)) {
-		status = PTR_ERR(cred);
-		goto out;
+	if (ctx != NULL) {
+		cred = ctx->cred;
+		path = &ctx->path;
+		fmode = ctx->mode;
 	}
-	state = nfs4_do_open(dir, &path, fmode, flags, sattr, cred);
+	state = nfs4_do_open(dir, path, fmode, flags, sattr, cred);
 	d_drop(dentry);
 	if (IS_ERR(state)) {
 		status = PTR_ERR(state);
-		goto out_putcred;
+		goto out;
 	}
 	d_add(dentry, igrab(state->inode));
 	nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
-	if (status == 0 && (nd->flags & LOOKUP_OPEN) != 0)
-		status = nfs4_intent_set_file(nd, &path, state, fmode);
+	if (ctx != NULL)
+		ctx->state = state;
 	else
-		nfs4_close_sync(&path, state, fmode);
-out_putcred:
-	put_rpccred(cred);
+		nfs4_close_sync(path, state, fmode);
 out:
 	return status;
 }
diff --git a/fs/nfs/proc.c b/fs/nfs/proc.c
index 611bec2..4ef39ae 100644
--- a/fs/nfs/proc.c
+++ b/fs/nfs/proc.c
@@ -258,7 +258,7 @@ static void nfs_free_createdata(const struct nfs_createdata *data)
 
 static int
 nfs_proc_create(struct inode *dir, struct dentry *dentry, struct iattr *sattr,
-		int flags, struct nameidata *nd)
+		int flags, struct nfs_open_context *ctx)
 {
 	struct nfs_createdata *data;
 	struct rpc_message msg = {
diff --git a/include/linux/nfs_xdr.h b/include/linux/nfs_xdr.h
index fc46192..b1484da 100644
--- a/include/linux/nfs_xdr.h
+++ b/include/linux/nfs_xdr.h
@@ -1032,7 +1032,7 @@ struct nfs_rpc_ops {
 	int	(*readlink)(struct inode *, struct page *, unsigned int,
 			    unsigned int);
 	int	(*create)  (struct inode *, struct dentry *,
-			    struct iattr *, int, struct nameidata *);
+			    struct iattr *, int, struct nfs_open_context *);
 	int	(*remove)  (struct inode *, struct qstr *);
 	void	(*unlink_setup)  (struct rpc_message *, struct inode *dir);
 	int	(*unlink_done) (struct rpc_task *, struct inode *);
-- 
1.7.2.3

[PATCH 6/6] NFS: Add an 'open_context' element to struct nfs_rpc_ops

[Trond Myklebust]

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
---
 fs/nfs/dir.c            |    7 ++++---
 fs/nfs/nfs4_fs.h        |    1 -
 fs/nfs/nfs4proc.c       |    3 ++-
 include/linux/nfs_xdr.h |    4 ++++
 4 files changed, 10 insertions(+), 5 deletions(-)

diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index e37ffdd..1e9e188 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -34,7 +34,6 @@
 #include <linux/mount.h>
 #include <linux/sched.h>
 
-#include "nfs4_fs.h"
 #include "delegation.h"
 #include "iostat.h"
 #include "internal.h"
@@ -1127,7 +1126,7 @@ static struct dentry *nfs_atomic_lookup(struct inode *dir, struct dentry *dentry
 
 	/* Open the file on the server */
 	nfs_block_sillyrename(dentry->d_parent);
-	inode = nfs4_atomic_open(dir, ctx, open_flags, &attr);
+	inode = NFS_PROTO(dir)->open_context(dir, ctx, open_flags, &attr);
 	if (IS_ERR(inode)) {
 		nfs_unblock_sillyrename(dentry->d_parent);
 		put_nfs_open_context(ctx);
@@ -1175,8 +1174,10 @@ static int nfs_open_revalidate(struct dentry *dentry, struct nameidata *nd)
 
 	if (!is_atomic_open(nd) || d_mountpoint(dentry))
 		goto no_open;
+
 	parent = dget_parent(dentry);
 	dir = parent->d_inode;
+
 	/* We can't create new files in nfs_open_revalidate(), so we
 	 * optimize away revalidation of negative dentries.
 	 */
@@ -1205,7 +1206,7 @@ static int nfs_open_revalidate(struct dentry *dentry, struct nameidata *nd)
 	 * operations that change the directory. We therefore save the
 	 * change attribute *before* we do the RPC call.
 	 */
-	inode = nfs4_atomic_open(dir, ctx, openflags, NULL);
+	inode = NFS_PROTO(dir)->open_context(dir, ctx, openflags, NULL);
 	if (IS_ERR(inode)) {
 		ret = PTR_ERR(inode);
 		switch (ret) {
diff --git a/fs/nfs/nfs4_fs.h b/fs/nfs/nfs4_fs.h
index 6cf12ba..d24a8e0 100644
--- a/fs/nfs/nfs4_fs.h
+++ b/fs/nfs/nfs4_fs.h
@@ -242,7 +242,6 @@ extern int nfs4_proc_renew(struct nfs_client *, struct rpc_cred *);
 extern int nfs4_init_clientid(struct nfs_client *, struct rpc_cred *);
 extern int nfs41_init_clientid(struct nfs_client *, struct rpc_cred *);
 extern int nfs4_do_close(struct path *path, struct nfs4_state *state, gfp_t gfp_mask, int wait);
-extern struct inode *nfs4_atomic_open(struct inode *, struct nfs_open_context *, int, struct iattr *);
 extern int nfs4_server_capabilities(struct nfs_server *server, struct nfs_fh *fhandle);
 extern int nfs4_proc_fs_locations(struct inode *dir, const struct qstr *name,
 		struct nfs4_fs_locations *fs_locations, struct page *page);
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 617b149..643abd2 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -1998,7 +1998,7 @@ out:
 	return status;
 }
 
-struct inode *
+static struct inode *
 nfs4_atomic_open(struct inode *dir, struct nfs_open_context *ctx, int open_flags, struct iattr *attr)
 {
 	struct nfs4_state *state;
@@ -5358,6 +5358,7 @@ const struct nfs_rpc_ops nfs_v4_clientops = {
 	.lock		= nfs4_proc_lock,
 	.clear_acl_cache = nfs4_zap_acl_attr,
 	.close_context  = nfs4_close_context,
+	.open_context	= nfs4_atomic_open,
 };
 
 /*
diff --git a/include/linux/nfs_xdr.h b/include/linux/nfs_xdr.h
index b1484da..6f345f8 100644
--- a/include/linux/nfs_xdr.h
+++ b/include/linux/nfs_xdr.h
@@ -1065,6 +1065,10 @@ struct nfs_rpc_ops {
 	int	(*lock_check_bounds)(const struct file_lock *);
 	void	(*clear_acl_cache)(struct inode *);
 	void	(*close_context)(struct nfs_open_context *ctx, int);
+	struct inode * (*open_context) (struct inode *dir,
+				struct nfs_open_context *ctx,
+				int open_flags,
+				struct iattr *iattr);
 };
 
 /*
-- 
1.7.2.3

Re: [PATCH 2/6] NFSv4: Further minor cleanups for nfs4_atomic_open()

[J. Bruce Fields]

On Thu, Sep 16, 2010 at 05:01:39PM -0400, Trond Myklebust wrote:
> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
> ---
>  fs/nfs/dir.c      |   21 +++++++++++++++------
>  fs/nfs/nfs4_fs.h  |    2 +-
>  fs/nfs/nfs4proc.c |   28 ++++------------------------
>  3 files changed, 20 insertions(+), 31 deletions(-)
> 
> diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
> index 17529b5..194676c 100644
> --- a/fs/nfs/dir.c
> +++ b/fs/nfs/dir.c
> @@ -1084,8 +1084,8 @@ static struct dentry *nfs_atomic_lookup(struct inode *dir, struct dentry *dentry
>  	struct nfs_open_context *ctx;
>  	struct iattr attr;
>  	struct dentry *res = NULL;
> +	struct inode *inode;
>  	int open_flags;
> -	int error;
>  
>  	dfprintk(VFS, "NFS: atomic_lookup(%s/%ld), %s\n",
>  			dir->i_sb->s_id, dir->i_ino, dentry->d_name.name);
> @@ -1125,13 +1125,15 @@ static struct dentry *nfs_atomic_lookup(struct inode *dir, struct dentry *dentry
>  	}
>  
>  	/* Open the file on the server */
> -	res = nfs4_atomic_open(dir, ctx, open_flags, &attr);
> -	if (IS_ERR(res)) {
> +	nfs_block_sillyrename(dentry->d_parent);

This looks like a bugfix, not just "minor cleanups"?

--b.

> +	inode = nfs4_atomic_open(dir, ctx, open_flags, &attr);
> +	if (IS_ERR(inode)) {
> +		nfs_unblock_sillyrename(dentry->d_parent);
>  		put_nfs_open_context(ctx);
> -		error = PTR_ERR(res);
> -		switch (error) {
> +		switch (PTR_ERR(inode)) {
>  			/* Make a negative dentry */
>  			case -ENOENT:
> +				d_add(dentry, NULL);
>  				res = NULL;
>  				goto out;
>  			/* This turned out not to be a regular file */
> @@ -1143,13 +1145,20 @@ static struct dentry *nfs_atomic_lookup(struct inode *dir, struct dentry *dentry
>  					goto no_open;
>  			/* case -EINVAL: */
>  			default:
> +				res = ERR_CAST(inode);
>  				goto out;
>  		}
>  	}
> -	if (res != NULL)
> +	res = d_add_unique(dentry, inode);
> +	if (res != NULL) {
> +		dput(ctx->path.dentry);
> +		ctx->path.dentry = dget(res);
>  		dentry = res;
> +	}
>  	nfs_intent_set_file(nd, ctx);
> +	nfs_unblock_sillyrename(dentry->d_parent);
>  out:
> +	nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
>  	return res;
>  no_open:
>  	return nfs_lookup(dir, dentry, nd);
> diff --git a/fs/nfs/nfs4_fs.h b/fs/nfs/nfs4_fs.h
> index c5cc2a6..8e1f639 100644
> --- a/fs/nfs/nfs4_fs.h
> +++ b/fs/nfs/nfs4_fs.h
> @@ -242,7 +242,7 @@ extern int nfs4_proc_renew(struct nfs_client *, struct rpc_cred *);
>  extern int nfs4_init_clientid(struct nfs_client *, struct rpc_cred *);
>  extern int nfs41_init_clientid(struct nfs_client *, struct rpc_cred *);
>  extern int nfs4_do_close(struct path *path, struct nfs4_state *state, gfp_t gfp_mask, int wait);
> -extern struct dentry *nfs4_atomic_open(struct inode *, struct nfs_open_context *, int, struct iattr *);
> +extern struct inode *nfs4_atomic_open(struct inode *, struct nfs_open_context *, int, struct iattr *);
>  extern int nfs4_open_revalidate(struct inode *, struct dentry *, int, struct nameidata *);
>  extern int nfs4_server_capabilities(struct nfs_server *server, struct nfs_fh *fhandle);
>  extern int nfs4_proc_fs_locations(struct inode *dir, const struct qstr *name,
> diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
> index 38c3bed..f8d41ee 100644
> --- a/fs/nfs/nfs4proc.c
> +++ b/fs/nfs/nfs4proc.c
> @@ -2024,37 +2024,17 @@ out_close:
>  	return ret;
>  }
>  
> -struct dentry *
> +struct inode *
>  nfs4_atomic_open(struct inode *dir, struct nfs_open_context *ctx, int open_flags, struct iattr *attr)
>  {
> -	struct dentry *dentry = ctx->path.dentry;
> -	struct dentry *parent;
>  	struct nfs4_state *state;
> -	struct dentry *res;
>  
> -	parent = dentry->d_parent;
>  	/* Protect against concurrent sillydeletes */
> -	nfs_block_sillyrename(parent);
>  	state = nfs4_do_open(dir, &ctx->path, ctx->mode, open_flags, attr, ctx->cred);
> -	if (IS_ERR(state)) {
> -		if (PTR_ERR(state) == -ENOENT) {
> -			d_add(dentry, NULL);
> -			nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
> -		}
> -		nfs_unblock_sillyrename(parent);
> -		return (struct dentry *)state;
> -	}
> -	res = d_add_unique(dentry, igrab(state->inode));
> -	if (res != NULL) {
> -		struct dentry *dummy = ctx->path.dentry;
> -
> -		ctx->path.dentry = dget(res);
> -		dput(dummy);
> -	}
> +	if (IS_ERR(state))
> +		return ERR_CAST(state);
>  	ctx->state = state;
> -	nfs_set_verifier(ctx->path.dentry, nfs_save_change_attribute(dir));
> -	nfs_unblock_sillyrename(parent);
> -	return res;
> +	return igrab(state->inode);
>  }
>  
>  int
> -- 
> 1.7.2.3
> 
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