[GFS2] Clean up inode number handling

This patch cleans up the inode number handling code. The main difference
is that instead of looking up the inodes using a struct gfs2_inum_host
we now use just the no_addr member of this structure. The tests relating
to no_formal_ino can then be done by the calling code. This has
advantages in that we want to do different things in different code
paths if the no_formal_ino doesn't match. In the NFS patch we want to
return -ESTALE, but in the ->lookup() path, its a bug in the fs if the
no_formal_ino doesn't match and thus we can withdraw in this case.

In order to later fix bz #201012, we need to be able to look up an inode
without knowing no_formal_ino, as the only information that is known to
us is the on-disk location of the inode in question.

This patch will also help us to fix bz #236099 at a later date by
cleaning up a lot of the code in that area.

There are no user visible changes as a result of this patch and there
are no changes to the on-disk format either.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

1 files changed, 17 insertions, 12 deletions

diff --git a/fs/gfs2/ops_export.c b/fs/gfs2/ops_export.c
index aad918337a46..51a8a14deb29 100644
--- a/fs/gfs2/ops_export.c
+++ b/fs/gfs2/ops_export.c
@@ -75,10 +75,10 @@ static int gfs2_encode_fh(struct dentry *dentry, __u32 *p, int *len,
             (connectable && *len < GFS2_LARGE_FH_SIZE))
                 return 255;
 
-        fh[0] = cpu_to_be32(ip->i_num.no_formal_ino >> 32);
-        fh[1] = cpu_to_be32(ip->i_num.no_formal_ino & 0xFFFFFFFF);
-        fh[2] = cpu_to_be32(ip->i_num.no_addr >> 32);
-        fh[3] = cpu_to_be32(ip->i_num.no_addr & 0xFFFFFFFF);
+        fh[0] = cpu_to_be32(ip->i_no_formal_ino >> 32);
+        fh[1] = cpu_to_be32(ip->i_no_formal_ino & 0xFFFFFFFF);
+        fh[2] = cpu_to_be32(ip->i_no_addr >> 32);
+        fh[3] = cpu_to_be32(ip->i_no_addr & 0xFFFFFFFF);
         *len = GFS2_SMALL_FH_SIZE;
 
         if (!connectable || inode == sb->s_root->d_inode)
@@ -90,10 +90,10 @@ static int gfs2_encode_fh(struct dentry *dentry, __u32 *p, int *len,
         igrab(inode);
         spin_unlock(&dentry->d_lock);
 
-        fh[4] = cpu_to_be32(ip->i_num.no_formal_ino >> 32);
-        fh[5] = cpu_to_be32(ip->i_num.no_formal_ino & 0xFFFFFFFF);
-        fh[6] = cpu_to_be32(ip->i_num.no_addr >> 32);
-        fh[7] = cpu_to_be32(ip->i_num.no_addr & 0xFFFFFFFF);
+        fh[4] = cpu_to_be32(ip->i_no_formal_ino >> 32);
+        fh[5] = cpu_to_be32(ip->i_no_formal_ino & 0xFFFFFFFF);
+        fh[6] = cpu_to_be32(ip->i_no_addr >> 32);
+        fh[7] = cpu_to_be32(ip->i_no_addr & 0xFFFFFFFF);
 
         fh[8]  = cpu_to_be32(inode->i_mode);
         fh[9]  = 0;     /* pad to double word */
@@ -144,7 +144,8 @@ static int gfs2_get_name(struct dentry *parent, char *name,
         ip = GFS2_I(inode);
 
         *name = 0;
-        gnfd.inum = ip->i_num;
+        gnfd.inum.no_addr = ip->i_no_addr;
+        gnfd.inum.no_formal_ino = ip->i_no_formal_ino;
         gnfd.name = name;
 
         error = gfs2_glock_nq_init(dip->i_gl, LM_ST_SHARED, 0, &gh);
@@ -202,9 +203,9 @@ static struct dentry *gfs2_get_dentry(struct super_block *sb, void *inum_obj)
 
         /* System files? */
 
-        inode = gfs2_ilookup(sb, inum);
+        inode = gfs2_ilookup(sb, inum->no_addr);
         if (inode) {
-                if (GFS2_I(inode)->i_num.no_formal_ino != inum->no_formal_ino) {
+                if (GFS2_I(inode)->i_no_formal_ino != inum->no_formal_ino) {
                         iput(inode);
                         return ERR_PTR(-ESTALE);
                 }
@@ -236,7 +237,7 @@ static struct dentry *gfs2_get_dentry(struct super_block *sb, void *inum_obj)
         gfs2_glock_dq_uninit(&rgd_gh);
         gfs2_glock_dq_uninit(&ri_gh);
 
-        inode = gfs2_inode_lookup(sb, inum, fh_obj->imode);
+        inode = gfs2_inode_lookup(sb, inum->no_addr, fh_obj->imode);
         if (!inode)
                 goto fail;
         if (IS_ERR(inode)) {
@@ -249,6 +250,10 @@ static struct dentry *gfs2_get_dentry(struct super_block *sb, void *inum_obj)
                 iput(inode);
                 goto fail;
         }
+        if (GFS2_I(inode)->i_no_formal_ino != inum->no_formal_ino) {
+                iput(inode);
+                goto fail;
+        }
 
         error = -EIO;
         if (GFS2_I(inode)->i_di.di_flags & GFS2_DIF_SYSTEM) {