Revert "fs/9p: rework qid2ino logic"

This reverts commit b91a26696ef38eae1442aa03104e60bb49d2ac99.

4 files changed, 31 insertions, 12 deletions

diff --git a/fs/9p/v9fs_vfs.h b/fs/9p/v9fs_vfs.h
index d3aefbec4de6..6873850ad93e 100644
--- a/fs/9p/v9fs_vfs.h
+++ b/fs/9p/v9fs_vfs.h
@@ -44,12 +44,7 @@ void v9fs_set_netfs_context(struct inode *inode);
 int v9fs_init_inode(struct v9fs_session_info *v9ses,
 		    struct inode *inode, umode_t mode, dev_t rdev);
 void v9fs_evict_inode(struct inode *inode);
-#if (BITS_PER_LONG == 32)
-#define QID2INO(q) ((ino_t) (((q)->path+2) ^ (((q)->path) >> 32)))
-#else
-#define QID2INO(q) ((ino_t) ((q)->path+2))
-#endif
-
+ino_t v9fs_qid2ino(struct p9_qid *qid);
 void v9fs_stat2inode(struct p9_wstat *stat, struct inode *inode,
 		      struct super_block *sb, unsigned int flags);
 void v9fs_stat2inode_dotl(struct p9_stat_dotl *stat, struct inode *inode,
diff --git a/fs/9p/vfs_dir.c b/fs/9p/vfs_dir.c
index e0d34e4e9076..4102759a5cb5 100644
--- a/fs/9p/vfs_dir.c
+++ b/fs/9p/vfs_dir.c
@@ -127,7 +127,7 @@ static int v9fs_dir_readdir(struct file *file, struct dir_context *ctx)
 			}
 
 			over = !dir_emit(ctx, st.name, strlen(st.name),
-					QID2INO(&st.qid), dt_type(&st));
+					 v9fs_qid2ino(&st.qid), dt_type(&st));
 			p9stat_free(&st);
 			if (over)
 				return 0;
@@ -184,7 +184,7 @@ static int v9fs_dir_readdir_dotl(struct file *file, struct dir_context *ctx)
 
 			if (!dir_emit(ctx, curdirent.d_name,
 				      strlen(curdirent.d_name),
-				      QID2INO(&curdirent.qid),
+				      v9fs_qid2ino(&curdirent.qid),
 				      curdirent.d_type))
 				return 0;
 
diff --git a/fs/9p/vfs_inode.c b/fs/9p/vfs_inode.c
index f70d712227aa..8da32de3c318 100644
--- a/fs/9p/vfs_inode.c
+++ b/fs/9p/vfs_inode.c
@@ -402,6 +402,7 @@ static struct inode *v9fs_qid_iget(struct super_block *sb,
 	dev_t rdev;
 	int retval;
 	umode_t umode;
+	unsigned long i_ino;
 	struct inode *inode;
 	struct v9fs_session_info *v9ses = sb->s_fs_info;
 	int (*test)(struct inode *inode, void *data);
@@ -411,7 +412,8 @@ static struct inode *v9fs_qid_iget(struct super_block *sb,
 	else
 		test = v9fs_test_inode;
 
-	inode = iget5_locked(sb, QID2INO(qid), test, v9fs_set_inode, st);
+	i_ino = v9fs_qid2ino(qid);
+	inode = iget5_locked(sb, i_ino, test, v9fs_set_inode, st);
 	if (!inode)
 		return ERR_PTR(-ENOMEM);
 	if (!(inode->i_state & I_NEW))
@@ -421,7 +423,7 @@ static struct inode *v9fs_qid_iget(struct super_block *sb,
 	 * FIXME!! we may need support for stale inodes
 	 * later.
 	 */
-	inode->i_ino = QID2INO(qid);
+	inode->i_ino = i_ino;
 	umode = p9mode2unixmode(v9ses, st, &rdev);
 	retval = v9fs_init_inode(v9ses, inode, umode, rdev);
 	if (retval)
@@ -1155,6 +1157,26 @@ v9fs_stat2inode(struct p9_wstat *stat, struct inode *inode,
 }
 
 /**
+ * v9fs_qid2ino - convert qid into inode number
+ * @qid: qid to hash
+ *
+ * BUG: potential for inode number collisions?
+ */
+
+ino_t v9fs_qid2ino(struct p9_qid *qid)
+{
+	u64 path = qid->path + 2;
+	ino_t i = 0;
+
+	if (sizeof(ino_t) == sizeof(path))
+		memcpy(&i, &path, sizeof(ino_t));
+	else
+		i = (ino_t) (path ^ (path >> 32));
+
+	return i;
+}
+
+/**
  * v9fs_vfs_get_link - follow a symlink path
  * @dentry: dentry for symlink
  * @inode: inode for symlink
diff --git a/fs/9p/vfs_inode_dotl.c b/fs/9p/vfs_inode_dotl.c
index 143ac03b7425..f56b17b69aca 100644
--- a/fs/9p/vfs_inode_dotl.c
+++ b/fs/9p/vfs_inode_dotl.c
@@ -100,6 +100,7 @@ static struct inode *v9fs_qid_iget_dotl(struct super_block *sb,
 					int new)
 {
 	int retval;
+	unsigned long i_ino;
 	struct inode *inode;
 	struct v9fs_session_info *v9ses = sb->s_fs_info;
 	int (*test)(struct inode *inode, void *data);
@@ -109,7 +110,8 @@ static struct inode *v9fs_qid_iget_dotl(struct super_block *sb,
 	else
 		test = v9fs_test_inode_dotl;
 
-	inode = iget5_locked(sb, QID2INO(qid), test, v9fs_set_inode_dotl, st);
+	i_ino = v9fs_qid2ino(qid);
+	inode = iget5_locked(sb, i_ino, test, v9fs_set_inode_dotl, st);
 	if (!inode)
 		return ERR_PTR(-ENOMEM);
 	if (!(inode->i_state & I_NEW))
@@ -119,7 +121,7 @@ static struct inode *v9fs_qid_iget_dotl(struct super_block *sb,
 	 * FIXME!! we may need support for stale inodes
 	 * later.
 	 */
-	inode->i_ino = QID2INO(qid);
+	inode->i_ino = i_ino;
 	retval = v9fs_init_inode(v9ses, inode,
 				 st->st_mode, new_decode_dev(st->st_rdev));
 	if (retval)