From 77b8a75f5bb461951148a7211ef30eecac5cb662 Mon Sep 17 00:00:00 2001
From: Al Viro <viro@zeniv.linux.org.uk>
Date: Fri, 4 Jun 2010 21:19:01 -0400
Subject: [PATCH] simplify get_cramfs_inode()

simply don't hash the inodes that don't have real inumber instead of
skipping them during iget5_locked(); as the result, simple iget_locked()
would do and we can get rid of cramfs ->drop_inode() as well.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
 fs/cramfs/inode.c | 88 ++++++++++++++++++++---------------------------
 1 file changed, 38 insertions(+), 50 deletions(-)

diff --git a/fs/cramfs/inode.c b/fs/cramfs/inode.c
index dd3634e4c96..a53b130b366 100644
--- a/fs/cramfs/inode.c
+++ b/fs/cramfs/inode.c
@@ -39,66 +39,55 @@ static DEFINE_MUTEX(read_mutex);
 #define CRAMINO(x)	(((x)->offset && (x)->size)?(x)->offset<<2:1)
 #define OFFSET(x)	((x)->i_ino)
 
-
-static int cramfs_iget5_test(struct inode *inode, void *opaque)
-{
-	struct cramfs_inode *cramfs_inode = opaque;
-	return inode->i_ino == CRAMINO(cramfs_inode) && inode->i_ino != 1;
-}
-
-static int cramfs_iget5_set(struct inode *inode, void *opaque)
+static void setup_inode(struct inode *inode, struct cramfs_inode * cramfs_inode)
 {
-	struct cramfs_inode *cramfs_inode = opaque;
-	inode->i_ino = CRAMINO(cramfs_inode);
-	return 0;
+	static struct timespec zerotime;
+	inode->i_mode = cramfs_inode->mode;
+	inode->i_uid = cramfs_inode->uid;
+	inode->i_size = cramfs_inode->size;
+	inode->i_blocks = (cramfs_inode->size - 1) / 512 + 1;
+	inode->i_gid = cramfs_inode->gid;
+	/* Struct copy intentional */
+	inode->i_mtime = inode->i_atime = inode->i_ctime = zerotime;
+	/* inode->i_nlink is left 1 - arguably wrong for directories,
+	   but it's the best we can do without reading the directory
+	   contents.  1 yields the right result in GNU find, even
+	   without -noleaf option. */
+	if (S_ISREG(inode->i_mode)) {
+		inode->i_fop = &generic_ro_fops;
+		inode->i_data.a_ops = &cramfs_aops;
+	} else if (S_ISDIR(inode->i_mode)) {
+		inode->i_op = &cramfs_dir_inode_operations;
+		inode->i_fop = &cramfs_directory_operations;
+	} else if (S_ISLNK(inode->i_mode)) {
+		inode->i_op = &page_symlink_inode_operations;
+		inode->i_data.a_ops = &cramfs_aops;
+	} else {
+		init_special_inode(inode, inode->i_mode,
+			old_decode_dev(cramfs_inode->size));
+	}
 }
 
 static struct inode *get_cramfs_inode(struct super_block *sb,
 				struct cramfs_inode * cramfs_inode)
 {
-	struct inode *inode = iget5_locked(sb, CRAMINO(cramfs_inode),
-					    cramfs_iget5_test, cramfs_iget5_set,
-					    cramfs_inode);
-	static struct timespec zerotime;
-
-	if (inode && (inode->i_state & I_NEW)) {
-		inode->i_mode = cramfs_inode->mode;
-		inode->i_uid = cramfs_inode->uid;
-		inode->i_size = cramfs_inode->size;
-		inode->i_blocks = (cramfs_inode->size - 1) / 512 + 1;
-		inode->i_gid = cramfs_inode->gid;
-		/* Struct copy intentional */
-		inode->i_mtime = inode->i_atime = inode->i_ctime = zerotime;
-		/* inode->i_nlink is left 1 - arguably wrong for directories,
-		   but it's the best we can do without reading the directory
-		   contents.  1 yields the right result in GNU find, even
-		   without -noleaf option. */
-		if (S_ISREG(inode->i_mode)) {
-			inode->i_fop = &generic_ro_fops;
-			inode->i_data.a_ops = &cramfs_aops;
-		} else if (S_ISDIR(inode->i_mode)) {
-			inode->i_op = &cramfs_dir_inode_operations;
-			inode->i_fop = &cramfs_directory_operations;
-		} else if (S_ISLNK(inode->i_mode)) {
-			inode->i_op = &page_symlink_inode_operations;
-			inode->i_data.a_ops = &cramfs_aops;
-		} else {
-			init_special_inode(inode, inode->i_mode,
-				old_decode_dev(cramfs_inode->size));
+	struct inode *inode;
+	if (CRAMINO(cramfs_inode) == 1) {
+		inode = new_inode(sb);
+		if (inode) {
+			inode->i_ino = 1;
+			setup_inode(inode, cramfs_inode);
+		}
+	} else {
+		inode = iget_locked(sb, CRAMINO(cramfs_inode));
+		if (inode) {
+			setup_inode(inode, cramfs_inode);
+			unlock_new_inode(inode);
 		}
-		unlock_new_inode(inode);
 	}
 	return inode;
 }
 
-static void cramfs_drop_inode(struct inode *inode)
-{
-	if (inode->i_ino == 1)
-		generic_delete_inode(inode);
-	else
-		generic_drop_inode(inode);
-}
-
 /*
  * We have our own block cache: don't fill up the buffer cache
  * with the rom-image, because the way the filesystem is set
@@ -542,7 +531,6 @@ static const struct super_operations cramfs_ops = {
 	.put_super	= cramfs_put_super,
 	.remount_fs	= cramfs_remount,
 	.statfs		= cramfs_statfs,
-	.drop_inode	= cramfs_drop_inode,
 };
 
 static int cramfs_get_sb(struct file_system_type *fs_type,
-- 
2.39.3