don't transliterate lower bits of ->intent.open.flags to FMODE_...

->create() instances are much happier that way...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/9p/vfs_inode.c b/fs/9p/vfs_inode.c
index 7f6c677..47f71eb 100644
--- a/fs/9p/vfs_inode.c
+++ b/fs/9p/vfs_inode.c
@@ -634,7 +634,7 @@
 	v9ses = v9fs_inode2v9ses(dir);
 	perm = unixmode2p9mode(v9ses, mode);
 	if (nd && nd->flags & LOOKUP_OPEN)
-		flags = nd->intent.open.flags - 1;
+		flags = nd->intent.open.flags;
 	else
 		flags = O_RDWR;
 
diff --git a/fs/9p/vfs_inode_dotl.c b/fs/9p/vfs_inode_dotl.c
index 691c78f..d148e69 100644
--- a/fs/9p/vfs_inode_dotl.c
+++ b/fs/9p/vfs_inode_dotl.c
@@ -174,7 +174,7 @@
 
 	v9ses = v9fs_inode2v9ses(dir);
 	if (nd && nd->flags & LOOKUP_OPEN)
-		flags = nd->intent.open.flags - 1;
+		flags = nd->intent.open.flags;
 	else {
 		/*
 		 * create call without LOOKUP_OPEN is due
diff --git a/fs/ceph/file.c b/fs/ceph/file.c
index 4698a5c..0a29245 100644
--- a/fs/ceph/file.c
+++ b/fs/ceph/file.c
@@ -226,7 +226,7 @@
 	struct inode *parent_inode = get_dentry_parent_inode(file->f_dentry);
 	struct ceph_mds_request *req;
 	int err;
-	int flags = nd->intent.open.flags - 1;  /* silly vfs! */
+	int flags = nd->intent.open.flags;
 
 	dout("ceph_lookup_open dentry %p '%.*s' flags %d mode 0%o\n",
 	     dentry, dentry->d_name.len, dentry->d_name.name, flags, mode);
diff --git a/fs/fuse/dir.c b/fs/fuse/dir.c
index e2b1400..47559dd 100644
--- a/fs/fuse/dir.c
+++ b/fs/fuse/dir.c
@@ -382,7 +382,7 @@
 	struct fuse_entry_out outentry;
 	struct fuse_file *ff;
 	struct file *file;
-	int flags = nd->intent.open.flags - 1;
+	int flags = nd->intent.open.flags;
 
 	if (fc->no_create)
 		return -ENOSYS;
diff --git a/fs/namei.c b/fs/namei.c
index 94fd0fa..5e65f67 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -1965,27 +1965,10 @@
 	return error;
 }
 
-/*
- * Note that while the flag value (low two bits) for sys_open means:
- *	00 - read-only
- *	01 - write-only
- *	10 - read-write
- *	11 - special
- * it is changed into
- *	00 - no permissions needed
- *	01 - read-permission
- *	10 - write-permission
- *	11 - read-write
- * for the internal routines (ie open_namei()/follow_link() etc)
- * This is more logical, and also allows the 00 "no perm needed"
- * to be used for symlinks (where the permissions are checked
- * later).
- *
-*/
 static inline int open_to_namei_flags(int flag)
 {
-	if ((flag+1) & O_ACCMODE)
-		flag++;
+	if ((flag & O_ACCMODE) == 3)
+		flag--;
 	return flag;
 }
 
diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index 1f46257..b5f63a5 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -1338,16 +1338,26 @@
 		return 0;
 	/* Are we trying to write to a read only partition? */
 	if (__mnt_is_readonly(nd->path.mnt) &&
-	    (nd->intent.open.flags & (O_CREAT|O_TRUNC|FMODE_WRITE)))
+	    (nd->intent.open.flags & (O_CREAT|O_TRUNC|O_ACCMODE)))
 		return 0;
 	return 1;
 }
 
+static fmode_t flags_to_mode(int flags)
+{
+	fmode_t res = (__force fmode_t)flags & FMODE_EXEC;
+	if ((flags & O_ACCMODE) != O_WRONLY)
+		res |= FMODE_READ;
+	if ((flags & O_ACCMODE) != O_RDONLY)
+		res |= FMODE_WRITE;
+	return res;
+}
+
 static struct nfs_open_context *create_nfs_open_context(struct dentry *dentry, int open_flags)
 {
 	struct nfs_open_context *ctx;
 	struct rpc_cred *cred;
-	fmode_t fmode = open_flags & (FMODE_READ | FMODE_WRITE | FMODE_EXEC);
+	fmode_t fmode = flags_to_mode(open_flags);
 
 	cred = rpc_lookup_cred();
 	if (IS_ERR(cred))
@@ -1567,7 +1577,7 @@
 	struct nfs_open_context *ctx = NULL;
 	struct iattr attr;
 	int error;
-	int open_flags = O_CREAT|O_EXCL|FMODE_READ;
+	int open_flags = O_CREAT|O_EXCL;
 
 	dfprintk(VFS, "NFS: create(%s/%ld), %s\n",
 			dir->i_sb->s_id, dir->i_ino, dentry->d_name.name);
@@ -1657,7 +1667,7 @@
 {
 	struct iattr attr;
 	int error;
-	int open_flags = O_CREAT|O_EXCL|FMODE_READ;
+	int open_flags = O_CREAT|O_EXCL;
 
 	dfprintk(VFS, "NFS: create(%s/%ld), %s\n",
 			dir->i_sb->s_id, dir->i_ino, dentry->d_name.name);
@@ -2256,11 +2266,11 @@
 {
 	int mask = 0;
 
-	if (openflags & FMODE_READ)
+	if ((openflags & O_ACCMODE) != O_WRONLY)
 		mask |= MAY_READ;
-	if (openflags & FMODE_WRITE)
+	if ((openflags & O_ACCMODE) != O_RDONLY)
 		mask |= MAY_WRITE;
-	if (openflags & FMODE_EXEC)
+	if (openflags & __FMODE_EXEC)
 		mask |= MAY_EXEC;
 	return mask;
 }