From 0a93887b99257d4271a790120aac6753068d11f0 Mon Sep 17 00:00:00 2001
From: NeilBrown <neilb@suse.de>
Date: Mon, 18 Oct 2010 10:32:33 +1100
Subject: [PATCH] Handle new inodes during roll-forward.

If we find an update for a new inode, we need to allow that,
and also clear the relevant bit in the inode map.

Signed-off-by: NeilBrown <neilb@suse.de>
---
 inode.c | 67 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 lafs.h  |  1 +
 roll.c  | 34 ++++++++++++++++++++++-------
 3 files changed, 94 insertions(+), 8 deletions(-)

diff --git a/inode.c b/inode.c
index a12fa0c..52659c3 100644
--- a/inode.c
+++ b/inode.c
@@ -1666,11 +1666,78 @@ retry:
 	lafs_dirty_dblock(b);
 	putdref(b, MKREF(inode_map_free));
 	lafs_checkpoint_unlock(fs);
+	mutex_unlock(&im->i_mutex);
+	iput(im);
+	return 0;
+}
+
+int lafs_inode_inuse(struct fs *fs, struct super_block *sb, u32 inum)
+{
+	/* This is used during roll-forward to register a newly created
+	 * inode in the inode map
+	 */
+	struct inode *im = lafs_iget(sb, 1, SYNC);
+	int bit;
+	unsigned long *buf;
+	struct datablock *b;
+	u32 bnum;
+	int err;
+
+	mutex_lock_nested(&im->i_mutex, I_MUTEX_QUOTA);
+
+	bnum = inum >> (3 + sb->s_blocksize_bits);
+	bit = inum - (bnum << (3 + sb->s_blocksize_bits));
+	if (bnum > LAFSI(im)->md.inodemap.size) {
+		/* inum to unbelievably big */
+		mutex_unlock(&im->i_mutex);
+		iput(im);
+		return -EINVAL;
+	}
+	b = lafs_get_block(im, bnum, NULL, GFP_KERNEL, MKREF(inode_map_free));
+	if (!b) {
+		mutex_unlock(&im->i_mutex);
+		iput(im);
+		return -ENOMEM;
+	}
+
+	err = lafs_read_block(b);
+	if (err) {
+		putdref(b, MKREF(inode_map_free));
 		mutex_unlock(&im->i_mutex);
+		iput(im);
+		return err;
+	}
+
+	lafs_iolock_written(&b->b);
+	set_bit(B_PinPending, &b->b.flags);
+	lafs_iounlock_block(&b->b);
+retry:
+	lafs_checkpoint_lock(fs);
+	err = lafs_pin_dblock(b, CleanSpace);
+	if (err == -EAGAIN) {
+		lafs_checkpoint_unlock_wait(fs);
+		goto retry;
+	}
+	BUG_ON(err < 0);
+	buf = map_dblock(b);
+	if (bnum == LAFSI(im)->md.inodemap.size) {
+		/* need to add a new block to the file */
+		memset(buf, 0xff, fs->blocksize);
+		LAFSI(im)->md.inodemap.size = bnum + 1;
+		lafs_dirty_inode(im);
+	}
+	generic___clear_le_bit(bit, buf);
+	unmap_dblock(b, buf);
+	lafs_dirty_dblock(b);
+	putdref(b, MKREF(inode_map_free));
+	lafs_checkpoint_unlock(fs);
+	mutex_unlock(&im->i_mutex);
 	iput(im);
 	return 0;
 }
 
+
+
 int lafs_setattr(struct dentry *dentry, struct iattr *attr)
 {
 	int err;
diff --git a/lafs.h b/lafs.h
index 42198fa..37cd4a1 100644
--- a/lafs.h
+++ b/lafs.h
@@ -152,6 +152,7 @@ void lafs_inode_fillblock(struct inode *ino);
 struct datablock *lafs_inode_dblock(struct inode *ino, int async, REFARG);
 struct datablock *lafs_inode_get_dblock(struct inode *ino, REFARG);
 int lafs_inode_handle_orphan(struct datablock *b);
+int lafs_inode_inuse(struct fs *fs, struct super_block *sb, u32 inum);
 
 static inline void lafs_iput_fs(struct inode *ino)
 {
diff --git a/roll.c b/roll.c
index 01d891e..a314075 100644
--- a/roll.c
+++ b/roll.c
@@ -235,6 +235,7 @@ roll_mini(struct fs *fs, int fsnum, int inum, int trunc,
 	  u32 bnum, int offset, int len, char *data)
 {
 	struct inode *inode;
+	struct inode *fsinode;
 	struct lafs_inode *li;
 	struct datablock *db = NULL;
 	int err = 0;
@@ -276,17 +277,31 @@ roll_mini(struct fs *fs, int fsnum, int inum, int trunc,
 			break;
 		}
 
-		lafs_iput_fs(inode);
+		fsinode = inode;
 		inode = lafs_iget_fs(fs, inum, bnum, SYNC);
 		if (IS_ERR(inode)) {
+			struct super_block *sb;
 			err = PTR_ERR(inode);
-			if (err != -ENOENT || offset != 0)
+			if (err != -ENOENT || offset != 0) {
+				lafs_iput_fs(fsinode);
 				return err;
+			}
 
-			/* FIXME creating new inode */
-			BUG();
+			db = lafs_get_block(fsinode, bnum, NULL, GFP_KERNEL,
+					    MKREF(roll));
+			sb = lafs_get_subset_sb(fsinode);
+			lafs_inode_inuse(fs, sb, bnum);
+			deactivate_super(sb);
+			lafs_iput_fs(fsinode);
+			if (!db)
+				db = ERR_PTR(-ENOMEM);
+		} else {
+			lafs_iput_fs(fsinode);
+			db = lafs_inode_dblock(inode, SYNC, MKREF(roll));
+			if (!IS_ERR(db))
+				/* Make sure block is in-sync with inode */
+				lafs_inode_fillblock(inode);
 		}
-		db = lafs_inode_dblock(inode, SYNC, MKREF(roll));
 		if (IS_ERR(db)) {
 			err = PTR_ERR(db);
 			break;
@@ -295,12 +310,15 @@ roll_mini(struct fs *fs, int fsnum, int inum, int trunc,
 		 * need that during roll-forward */
 		set_bit(B_PinPending, &db->b.flags);
 		lafs_pin_dblock(db, CleanSpace);
-		/* Make sure block is in-sync with inode */
-		lafs_inode_fillblock(inode);
 		buf = map_dblock(db);
 		memcpy(buf+offset, data, len);
 		unmap_dblock(db, buf);
-		err = lafs_import_inode(inode, db);
+		if (inode)
+			err = lafs_import_inode(inode, db);
+		else {
+			inode = lafs_iget_fs(fs, inum, bnum, SYNC);
+
+		}
 		lafs_dirty_dblock(db);
 		break;
 
-- 
2.39.5