xfs: move v1 inode conversion to xfs_inode_from_disk

So we don't have to carry an di_onlink variable around anymore, move
the inode conversion from v1 inode format to v2 inode format into
xfs_inode_from_disk(). This means we can remove the di_onlink fields
from the struct xfs_icdinode.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>

fs/xfs/libxfs/xfs_inode_buf.c

@@ -204,13 +204,25 @@ xfs_inode_from_disk(
 
 	to->di_mode = be16_to_cpu(from->di_mode);
 	to->di_version = from ->di_version;
+
+	/*
+	 * Convert v1 inodes immediately to v2 inode format as this is the
+	 * minimum inode version format we support in the rest of the code.
+	 */
+	if (to->di_version == 1) {
+		to->di_nlink = be16_to_cpu(from->di_onlink);
+		to->di_projid_lo = 0;
+		to->di_projid_hi = 0;
+		to->di_version = 2;
+	} else {
+		to->di_nlink = be32_to_cpu(from->di_nlink);
+		to->di_projid_lo = be16_to_cpu(from->di_projid_lo);
+		to->di_projid_hi = be16_to_cpu(from->di_projid_hi);
+	}
+
 	to->di_format = from->di_format;
-	to->di_onlink = be16_to_cpu(from->di_onlink);
 	to->di_uid = be32_to_cpu(from->di_uid);
 	to->di_gid = be32_to_cpu(from->di_gid);
-	to->di_nlink = be32_to_cpu(from->di_nlink);
-	to->di_projid_lo = be16_to_cpu(from->di_projid_lo);
-	to->di_projid_hi = be16_to_cpu(from->di_projid_hi);
 	to->di_flushiter = be16_to_cpu(from->di_flushiter);
 
 	/*
@@ -256,11 +268,11 @@ xfs_inode_to_disk(
 	struct inode		*inode = VFS_I(ip);
 
 	to->di_magic = cpu_to_be16(XFS_DINODE_MAGIC);
+	to->di_onlink = 0;
 
 	to->di_mode = cpu_to_be16(from->di_mode);
 	to->di_version = from->di_version;
 	to->di_format = from->di_format;
-	to->di_onlink = cpu_to_be16(from->di_onlink);
 	to->di_uid = cpu_to_be32(from->di_uid);
 	to->di_gid = cpu_to_be32(from->di_gid);
 	to->di_nlink = cpu_to_be32(from->di_nlink);
@@ -310,9 +322,9 @@ xfs_log_dinode_to_disk(
 {
 	to->di_magic = cpu_to_be16(from->di_magic);
 	to->di_mode = cpu_to_be16(from->di_mode);
-	to->di_version = from ->di_version;
+	to->di_version = from->di_version;
 	to->di_format = from->di_format;
-	to->di_onlink = cpu_to_be16(from->di_onlink);
+	to->di_onlink = 0;
 	to->di_uid = cpu_to_be32(from->di_uid);
 	to->di_gid = cpu_to_be32(from->di_gid);
 	to->di_nlink = cpu_to_be32(from->di_nlink);
@@ -492,21 +504,7 @@ xfs_iread(
 		ip->i_d.di_mode = 0;
 	}
 
-	/*
-	 * Automatically convert version 1 inode formats in memory to version 2
-	 * inode format. If the inode is modified, it will get logged and
-	 * rewritten as a version 2 inode. We can do this because we set the
-	 * superblock feature bit for v2 inodes unconditionally during mount
-	 * and it means the reast of the code can assume the inode version is 2
-	 * or higher.
-	 */
-	if (ip->i_d.di_version == 1) {
-		ip->i_d.di_version = 2;
-		ip->i_d.di_nlink = ip->i_d.di_onlink;
-		ip->i_d.di_onlink = 0;
-		xfs_set_projid(ip, 0);
-	}
-
+	ASSERT(ip->i_d.di_version >= 2);
 	ip->i_delayed_blks = 0;
 
 	/*

fs/xfs/libxfs/xfs_inode_buf.h

@@ -31,7 +31,6 @@ struct xfs_icdinode {
 	__uint16_t	di_mode;	/* mode and type of file */
 	__int8_t	di_version;	/* inode version */
 	__int8_t	di_format;	/* format of di_c data */
-	__uint16_t	di_onlink;	/* old number of links to file */
 	__uint16_t	di_flushiter;	/* incremented on flush */
 	__uint32_t	di_uid;		/* owner's user id */
 	__uint32_t	di_gid;		/* owner's group id */

fs/xfs/libxfs/xfs_log_format.h

@@ -369,7 +369,7 @@ struct xfs_log_dinode {
 	__uint16_t	di_mode;	/* mode and type of file */
 	__int8_t	di_version;	/* inode version */
 	__int8_t	di_format;	/* format of di_c data */
-	__uint16_t	di_onlink;	/* old number of links to file */
+	__uint8_t	di_pad3[2];	/* unused in v2/3 inodes */
 	__uint32_t	di_uid;		/* owner's user id */
 	__uint32_t	di_gid;		/* owner's group id */
 	__uint32_t	di_nlink;	/* number of links to file */

fs/xfs/xfs_inode.c

@@ -803,9 +803,7 @@ xfs_ialloc(
 		ip->i_d.di_version = 2;
 
 	ip->i_d.di_mode = mode;
-	ip->i_d.di_onlink = 0;
 	ip->i_d.di_nlink = nlink;
-	ASSERT(ip->i_d.di_nlink == nlink);
 	ip->i_d.di_uid = xfs_kuid_to_uid(current_fsuid());
 	ip->i_d.di_gid = xfs_kgid_to_gid(current_fsgid());
 	xfs_set_projid(ip, prid);

fs/xfs/xfs_inode_item.c

@@ -336,7 +336,6 @@ xfs_inode_to_log_dinode(
 	to->di_mode = from->di_mode;
 	to->di_version = from->di_version;
 	to->di_format = from->di_format;
-	to->di_onlink = from->di_onlink;
 	to->di_uid = from->di_uid;
 	to->di_gid = from->di_gid;
 	to->di_nlink = from->di_nlink;
@@ -344,6 +343,7 @@ xfs_inode_to_log_dinode(
 	to->di_projid_hi = from->di_projid_hi;
 
 	memset(to->di_pad, 0, sizeof(to->di_pad));
+	memset(to->di_pad3, 0, sizeof(to->di_pad3));
 	to->di_atime.t_sec = inode->i_atime.tv_sec;
 	to->di_atime.t_nsec = inode->i_atime.tv_nsec;
 	to->di_mtime.t_sec = inode->i_mtime.tv_sec;