1 files changed, 119 insertions, 108 deletions

diff --git a/fs/9p/vfs_inode.c b/fs/9p/vfs_inode.c
index 57ccb7537dae..25b018efb8ab 100644
--- a/fs/9p/vfs_inode.c
+++ b/fs/9p/vfs_inode.c
@@ -192,9 +192,6 @@ int v9fs_uflags2omode(int uflags, int extended)
 		break;
 	}
 
-	if (uflags & O_TRUNC)
-		ret |= P9_OTRUNC;
-
 	if (extended) {
 		if (uflags & O_EXCL)
 			ret |= P9_OEXCL;
@@ -228,9 +225,9 @@ v9fs_blank_wstat(struct p9_wstat *wstat)
 	wstat->uid = NULL;
 	wstat->gid = NULL;
 	wstat->muid = NULL;
-	wstat->n_uid = ~0;
-	wstat->n_gid = ~0;
-	wstat->n_muid = ~0;
+	wstat->n_uid = INVALID_UID;
+	wstat->n_gid = INVALID_GID;
+	wstat->n_muid = INVALID_UID;
 	wstat->extension = NULL;
 }
 
@@ -695,9 +692,7 @@ v9fs_create(struct v9fs_session_info *v9ses, struct inode *dir,
 				   "inode creation failed %d\n", err);
 			goto error;
 		}
-		err = v9fs_fid_add(dentry, fid);
-		if (err < 0)
-			goto error;
+		v9fs_fid_add(dentry, fid);
 		d_instantiate(dentry, inode);
 	}
 	return ofid;
@@ -712,88 +707,34 @@ error:
 }
 
 /**
- * v9fs_vfs_create - VFS hook to create files
+ * v9fs_vfs_create - VFS hook to create a regular file
+ *
+ * open(.., O_CREAT) is handled in v9fs_vfs_atomic_open().  This is only called
+ * for mknod(2).
+ *
  * @dir: directory inode that is being created
  * @dentry:  dentry that is being deleted
  * @mode: create permissions
- * @nd: path information
  *
  */
 
 static int
 v9fs_vfs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
-		struct nameidata *nd)
+		bool excl)
 {
-	int err;
-	u32 perm;
-	int flags;
-	struct file *filp;
-	struct v9fs_inode *v9inode;
-	struct v9fs_session_info *v9ses;
-	struct p9_fid *fid, *inode_fid;
-
-	err = 0;
-	fid = NULL;
-	v9ses = v9fs_inode2v9ses(dir);
-	perm = unixmode2p9mode(v9ses, mode);
-	if (nd)
-		flags = nd->intent.open.flags;
-	else
-		flags = O_RDWR;
+	struct v9fs_session_info *v9ses = v9fs_inode2v9ses(dir);
+	u32 perm = unixmode2p9mode(v9ses, mode);
+	struct p9_fid *fid;
 
-	fid = v9fs_create(v9ses, dir, dentry, NULL, perm,
-				v9fs_uflags2omode(flags,
-						v9fs_proto_dotu(v9ses)));
-	if (IS_ERR(fid)) {
-		err = PTR_ERR(fid);
-		fid = NULL;
-		goto error;
-	}
+	/* P9_OEXCL? */
+	fid = v9fs_create(v9ses, dir, dentry, NULL, perm, P9_ORDWR);
+	if (IS_ERR(fid))
+		return PTR_ERR(fid);
 
 	v9fs_invalidate_inode_attr(dir);
-	/* if we are opening a file, assign the open fid to the file */
-	if (nd) {
-		v9inode = V9FS_I(dentry->d_inode);
-		mutex_lock(&v9inode->v_mutex);
-		if (v9ses->cache && !v9inode->writeback_fid &&
-		    ((flags & O_ACCMODE) != O_RDONLY)) {
-			/*
-			 * clone a fid and add it to writeback_fid
-			 * we do it during open time instead of
-			 * page dirty time via write_begin/page_mkwrite
-			 * because we want write after unlink usecase
-			 * to work.
-			 */
-			inode_fid = v9fs_writeback_fid(dentry);
-			if (IS_ERR(inode_fid)) {
-				err = PTR_ERR(inode_fid);
-				mutex_unlock(&v9inode->v_mutex);
-				goto error;
-			}
-			v9inode->writeback_fid = (void *) inode_fid;
-		}
-		mutex_unlock(&v9inode->v_mutex);
-		filp = lookup_instantiate_filp(nd, dentry, generic_file_open);
-		if (IS_ERR(filp)) {
-			err = PTR_ERR(filp);
-			goto error;
-		}
-
-		filp->private_data = fid;
-#ifdef CONFIG_9P_FSCACHE
-		if (v9ses->cache)
-			v9fs_cache_inode_set_cookie(dentry->d_inode, filp);
-#endif
-	} else
-		p9_client_clunk(fid);
+	p9_client_clunk(fid);
 
 	return 0;
-
-error:
-	if (fid)
-		p9_client_clunk(fid);
-
-	return err;
 }
 
 /**
@@ -839,7 +780,7 @@ static int v9fs_vfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode
  */
 
 struct dentry *v9fs_vfs_lookup(struct inode *dir, struct dentry *dentry,
-				      struct nameidata *nameidata)
+				      unsigned int flags)
 {
 	struct dentry *res;
 	struct super_block *sb;
@@ -847,10 +788,9 @@ struct dentry *v9fs_vfs_lookup(struct inode *dir, struct dentry *dentry,
 	struct p9_fid *dfid, *fid;
 	struct inode *inode;
 	char *name;
-	int result = 0;
 
-	p9_debug(P9_DEBUG_VFS, "dir: %p dentry: (%s) %p nameidata: %p\n",
-		 dir, dentry->d_name.name, dentry, nameidata);
+	p9_debug(P9_DEBUG_VFS, "dir: %p dentry: (%s) %p flags: %x\n",
+		 dir, dentry->d_name.name, dentry, flags);
 
 	if (dentry->d_name.len > NAME_MAX)
 		return ERR_PTR(-ENAMETOOLONG);
@@ -865,13 +805,11 @@ struct dentry *v9fs_vfs_lookup(struct inode *dir, struct dentry *dentry,
 	name = (char *) dentry->d_name.name;
 	fid = p9_client_walk(dfid, 1, &name, 1);
 	if (IS_ERR(fid)) {
-		result = PTR_ERR(fid);
-		if (result == -ENOENT) {
-			inode = NULL;
-			goto inst_out;
+		if (fid == ERR_PTR(-ENOENT)) {
+			d_add(dentry, NULL);
+			return NULL;
 		}
-
-		return ERR_PTR(result);
+		return ERR_CAST(fid);
 	}
 	/*
 	 * Make sure we don't use a wrong inode due to parallel
@@ -883,14 +821,9 @@ struct dentry *v9fs_vfs_lookup(struct inode *dir, struct dentry *dentry,
 	else
 		inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
 	if (IS_ERR(inode)) {
-		result = PTR_ERR(inode);
-		inode = NULL;
-		goto error;
+		p9_client_clunk(fid);
+		return ERR_CAST(inode);
 	}
-	result = v9fs_fid_add(dentry, fid);
-	if (result < 0)
-		goto error_iput;
-inst_out:
 	/*
 	 * If we had a rename on the server and a parallel lookup
 	 * for the new name, then make sure we instantiate with
@@ -899,15 +832,93 @@ inst_out:
 	 * k/b.
 	 */
 	res = d_materialise_unique(dentry, inode);
-	if (!IS_ERR(res))
-		return res;
-	result = PTR_ERR(res);
-error_iput:
-	iput(inode);
-error:
-	p9_client_clunk(fid);
+	if (!res)
+		v9fs_fid_add(dentry, fid);
+	else if (!IS_ERR(res))
+		v9fs_fid_add(res, fid);
+	else
+		p9_client_clunk(fid);
+	return res;
+}
+
+static int
+v9fs_vfs_atomic_open(struct inode *dir, struct dentry *dentry,
+		     struct file *file, unsigned flags, umode_t mode,
+		     int *opened)
+{
+	int err;
+	u32 perm;
+	struct v9fs_inode *v9inode;
+	struct v9fs_session_info *v9ses;
+	struct p9_fid *fid, *inode_fid;
+	struct dentry *res = NULL;
 
-	return ERR_PTR(result);
+	if (d_unhashed(dentry)) {
+		res = v9fs_vfs_lookup(dir, dentry, 0);
+		if (IS_ERR(res))
+			return PTR_ERR(res);
+
+		if (res)
+			dentry = res;
+	}
+
+	/* Only creates */
+	if (!(flags & O_CREAT) || dentry->d_inode)
+		return finish_no_open(file, res);
+
+	err = 0;
+	fid = NULL;
+	v9ses = v9fs_inode2v9ses(dir);
+	perm = unixmode2p9mode(v9ses, mode);
+	fid = v9fs_create(v9ses, dir, dentry, NULL, perm,
+				v9fs_uflags2omode(flags,
+						v9fs_proto_dotu(v9ses)));
+	if (IS_ERR(fid)) {
+		err = PTR_ERR(fid);
+		fid = NULL;
+		goto error;
+	}
+
+	v9fs_invalidate_inode_attr(dir);
+	v9inode = V9FS_I(dentry->d_inode);
+	mutex_lock(&v9inode->v_mutex);
+	if (v9ses->cache && !v9inode->writeback_fid &&
+	    ((flags & O_ACCMODE) != O_RDONLY)) {
+		/*
+		 * clone a fid and add it to writeback_fid
+		 * we do it during open time instead of
+		 * page dirty time via write_begin/page_mkwrite
+		 * because we want write after unlink usecase
+		 * to work.
+		 */
+		inode_fid = v9fs_writeback_fid(dentry);
+		if (IS_ERR(inode_fid)) {
+			err = PTR_ERR(inode_fid);
+			mutex_unlock(&v9inode->v_mutex);
+			goto error;
+		}
+		v9inode->writeback_fid = (void *) inode_fid;
+	}
+	mutex_unlock(&v9inode->v_mutex);
+	err = finish_open(file, dentry, generic_file_open, opened);
+	if (err)
+		goto error;
+
+	file->private_data = fid;
+#ifdef CONFIG_9P_FSCACHE
+	if (v9ses->cache)
+		v9fs_cache_inode_set_cookie(dentry->d_inode, file);
+#endif
+
+	*opened |= FILE_CREATED;
+out:
+	dput(res);
+	return err;
+
+error:
+	if (fid)
+		p9_client_clunk(fid);
+	goto out;
 }
 
 /**
@@ -1043,13 +1054,11 @@ static int
 v9fs_vfs_getattr(struct vfsmount *mnt, struct dentry *dentry,
 		 struct kstat *stat)
 {
-	int err;
 	struct v9fs_session_info *v9ses;
 	struct p9_fid *fid;
 	struct p9_wstat *st;
 
 	p9_debug(P9_DEBUG_VFS, "dentry: %p\n", dentry);
-	err = -EPERM;
 	v9ses = v9fs_dentry2v9ses(dentry);
 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
 		generic_fillattr(dentry->d_inode, stat);
@@ -1250,12 +1259,12 @@ static int v9fs_readlink(struct dentry *dentry, char *buffer, int buflen)
 	}
 
 	/* copy extension buffer into buffer */
-	strncpy(buffer, st->extension, buflen);
+	retval = min(strlen(st->extension)+1, (size_t)buflen);
+	memcpy(buffer, st->extension, retval);
 
-	p9_debug(P9_DEBUG_VFS, "%s -> %s (%s)\n",
-		 dentry->d_name.name, st->extension, buffer);
+	p9_debug(P9_DEBUG_VFS, "%s -> %s (%.*s)\n",
+		 dentry->d_name.name, st->extension, buflen, buffer);
 
-	retval = strnlen(buffer, buflen);
 done:
 	p9stat_free(st);
 	kfree(st);
@@ -1488,6 +1497,7 @@ out:
 static const struct inode_operations v9fs_dir_inode_operations_dotu = {
 	.create = v9fs_vfs_create,
 	.lookup = v9fs_vfs_lookup,
+	.atomic_open = v9fs_vfs_atomic_open,
 	.symlink = v9fs_vfs_symlink,
 	.link = v9fs_vfs_link,
 	.unlink = v9fs_vfs_unlink,
@@ -1502,6 +1512,7 @@ static const struct inode_operations v9fs_dir_inode_operations_dotu = {
 static const struct inode_operations v9fs_dir_inode_operations = {
 	.create = v9fs_vfs_create,
 	.lookup = v9fs_vfs_lookup,
+	.atomic_open = v9fs_vfs_atomic_open,
 	.unlink = v9fs_vfs_unlink,
 	.mkdir = v9fs_vfs_mkdir,
 	.rmdir = v9fs_vfs_rmdir,