Merge tag '9p-for-6.9' of git://git.kernel.org/pub/scm/linux/kernel/git/ericvh/v9fs

Pull 9p updates from Eric Van Hensbergen:
 "This includes a number of patches addressing improvements in the cache
  portions of the 9p client.

  The biggest improvements have to do with fixing handling of inodes and
  eliminating duplicate structures and unnecessary allocation/release of
  inode structures and many associated unnecessary protocol traffic.
  This also dramatically reduced code complexity across the code and
  sets us up to add proper temporal cache capabilities"

* tag '9p-for-6.9' of git://git.kernel.org/pub/scm/linux/kernel/git/ericvh/v9fs:
  fs/9p: fix dups even in uncached mode
  fs/9p: simplify iget to remove unnecessary paths
  fs/9p: rework qid2ino logic
  fs/9p: Eliminate now unused v9fs_get_inode
  fs/9p: Eliminate redundant non-cache path in mknod
  fs/9p: remove walk and inode allocation from symlink
  fs/9p: convert mkdir to use get_new_inode
  fs/9p: switch vfsmount to use v9fs_get_new_inode

Author: torvalds

fs/9p/v9fs.h

@@ -179,16 +179,13 @@ extern int v9fs_vfs_rename(struct mnt_idmap *idmap,
 			   struct inode *old_dir, struct dentry *old_dentry,
 			   struct inode *new_dir, struct dentry *new_dentry,
 			   unsigned int flags);
-extern struct inode *v9fs_inode_from_fid(struct v9fs_session_info *v9ses,
-					 struct p9_fid *fid,
-					 struct super_block *sb, int new);
+extern struct inode *v9fs_fid_iget(struct super_block *sb, struct p9_fid *fid);
 extern const struct inode_operations v9fs_dir_inode_operations_dotl;
 extern const struct inode_operations v9fs_file_inode_operations_dotl;
 extern const struct inode_operations v9fs_symlink_inode_operations_dotl;
 extern const struct netfs_request_ops v9fs_req_ops;
-extern struct inode *v9fs_inode_from_fid_dotl(struct v9fs_session_info *v9ses,
-					      struct p9_fid *fid,
-					      struct super_block *sb, int new);
+extern struct inode *v9fs_fid_iget_dotl(struct super_block *sb,
+					struct p9_fid *fid);
 
 /* other default globals */
 #define V9FS_PORT	564
@@ -230,27 +227,9 @@ v9fs_get_inode_from_fid(struct v9fs_session_info *v9ses, struct p9_fid *fid,
 			struct super_block *sb)
 {
 	if (v9fs_proto_dotl(v9ses))
-		return v9fs_inode_from_fid_dotl(v9ses, fid, sb, 0);
+		return v9fs_fid_iget_dotl(sb, fid);
 	else
-		return v9fs_inode_from_fid(v9ses, fid, sb, 0);
-}
-
-/**
- * v9fs_get_new_inode_from_fid - Helper routine to populate an inode by
- * issuing a attribute request
- * @v9ses: session information
- * @fid: fid to issue attribute request for
- * @sb: superblock on which to create inode
- *
- */
-static inline struct inode *
-v9fs_get_new_inode_from_fid(struct v9fs_session_info *v9ses, struct p9_fid *fid,
-			    struct super_block *sb)
-{
-	if (v9fs_proto_dotl(v9ses))
-		return v9fs_inode_from_fid_dotl(v9ses, fid, sb, 1);
-	else
-		return v9fs_inode_from_fid(v9ses, fid, sb, 1);
+		return v9fs_fid_iget(sb, fid);
 }
 
 #endif

fs/9p/v9fs_vfs.h

@@ -40,13 +40,16 @@ extern struct kmem_cache *v9fs_inode_cache;
 
 struct inode *v9fs_alloc_inode(struct super_block *sb);
 void v9fs_free_inode(struct inode *inode);
-struct inode *v9fs_get_inode(struct super_block *sb, umode_t mode,
-			     dev_t rdev);
 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);
+		    struct inode *inode, struct p9_qid *qid, umode_t mode, dev_t rdev);
 void v9fs_evict_inode(struct inode *inode);
-ino_t v9fs_qid2ino(struct p9_qid *qid);
+#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
+
 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,

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),
-					 v9fs_qid2ino(&st.qid), dt_type(&st));
+					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),
-				      v9fs_qid2ino(&curdirent.qid),
+				      QID2INO(&curdirent.qid),
 				      curdirent.d_type))
 				return 0;
 

fs/9p/vfs_inode.c

@@ -253,9 +253,12 @@ 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)
+		    struct inode *inode, struct p9_qid *qid, umode_t mode, dev_t rdev)
 {
 	int err = 0;
+	struct v9fs_inode *v9inode = V9FS_I(inode);
+
+	memcpy(&v9inode->qid, qid, sizeof(struct p9_qid));
 
 	inode_init_owner(&nop_mnt_idmap, inode, NULL, mode);
 	inode->i_blocks = 0;
@@ -331,36 +334,6 @@ int v9fs_init_inode(struct v9fs_session_info *v9ses,
 
 }
 
-/**
- * v9fs_get_inode - helper function to setup an inode
- * @sb: superblock
- * @mode: mode to setup inode with
- * @rdev: The device numbers to set
- */
-
-struct inode *v9fs_get_inode(struct super_block *sb, umode_t mode, dev_t rdev)
-{
-	int err;
-	struct inode *inode;
-	struct v9fs_session_info *v9ses = sb->s_fs_info;
-
-	p9_debug(P9_DEBUG_VFS, "super block: %p mode: %ho\n", sb, mode);
-
-	inode = new_inode(sb);
-	if (!inode) {
-		pr_warn("%s (%d): Problem allocating inode\n",
-			__func__, task_pid_nr(current));
-		return ERR_PTR(-ENOMEM);
-	}
-	err = v9fs_init_inode(v9ses, inode, mode, rdev);
-	if (err) {
-		iput(inode);
-		return ERR_PTR(err);
-	}
-	v9fs_set_netfs_context(inode);
-	return inode;
-}
-
 /**
  * v9fs_evict_inode - Remove an inode from the inode cache
  * @inode: inode to release
@@ -384,82 +357,40 @@ void v9fs_evict_inode(struct inode *inode)
 #endif
 }
 
-static int v9fs_test_inode(struct inode *inode, void *data)
-{
-	int umode;
-	dev_t rdev;
-	struct v9fs_inode *v9inode = V9FS_I(inode);
-	struct p9_wstat *st = (struct p9_wstat *)data;
-	struct v9fs_session_info *v9ses = v9fs_inode2v9ses(inode);
-
-	umode = p9mode2unixmode(v9ses, st, &rdev);
-	/* don't match inode of different type */
-	if (inode_wrong_type(inode, umode))
-		return 0;
-
-	/* compare qid details */
-	if (memcmp(&v9inode->qid.version,
-		   &st->qid.version, sizeof(v9inode->qid.version)))
-		return 0;
-
-	if (v9inode->qid.type != st->qid.type)
-		return 0;
-
-	if (v9inode->qid.path != st->qid.path)
-		return 0;
-	return 1;
-}
-
-static int v9fs_test_new_inode(struct inode *inode, void *data)
-{
-	return 0;
-}
-
-static int v9fs_set_inode(struct inode *inode,  void *data)
-{
-	struct v9fs_inode *v9inode = V9FS_I(inode);
-	struct p9_wstat *st = (struct p9_wstat *)data;
-
-	memcpy(&v9inode->qid, &st->qid, sizeof(st->qid));
-	return 0;
-}
-
-static struct inode *v9fs_qid_iget(struct super_block *sb,
-				   struct p9_qid *qid,
-				   struct p9_wstat *st,
-				   int new)
+struct inode *v9fs_fid_iget(struct super_block *sb, struct p9_fid *fid)
 {
 	dev_t rdev;
 	int retval;
 	umode_t umode;
-	unsigned long i_ino;
 	struct inode *inode;
+	struct p9_wstat *st;
 	struct v9fs_session_info *v9ses = sb->s_fs_info;
-	int (*test)(struct inode *inode, void *data);
 
-	if (new)
-		test = v9fs_test_new_inode;
-	else
-		test = v9fs_test_inode;
-
-	i_ino = v9fs_qid2ino(qid);
-	inode = iget5_locked(sb, i_ino, test, v9fs_set_inode, st);
-	if (!inode)
+	inode = iget_locked(sb, QID2INO(&fid->qid));
+	if (unlikely(!inode))
 		return ERR_PTR(-ENOMEM);
 	if (!(inode->i_state & I_NEW))
 		return inode;
+
 	/*
 	 * initialize the inode with the stat info
 	 * FIXME!! we may need support for stale inodes
 	 * later.
 	 */
-	inode->i_ino = i_ino;
+	st = p9_client_stat(fid);
+	if (IS_ERR(st)) {
+		retval = PTR_ERR(st);
+		goto error;
+	}
+
 	umode = p9mode2unixmode(v9ses, st, &rdev);
-	retval = v9fs_init_inode(v9ses, inode, umode, rdev);
+	retval = v9fs_init_inode(v9ses, inode, &fid->qid, umode, rdev);
+	v9fs_stat2inode(st, inode, sb, 0);
+	p9stat_free(st);
+	kfree(st);
 	if (retval)
 		goto error;
 
-	v9fs_stat2inode(st, inode, sb, 0);
 	v9fs_set_netfs_context(inode);
 	v9fs_cache_inode_get_cookie(inode);
 	unlock_new_inode(inode);
@@ -470,23 +401,6 @@ static struct inode *v9fs_qid_iget(struct super_block *sb,
 
 }
 
-struct inode *
-v9fs_inode_from_fid(struct v9fs_session_info *v9ses, struct p9_fid *fid,
-		    struct super_block *sb, int new)
-{
-	struct p9_wstat *st;
-	struct inode *inode = NULL;
-
-	st = p9_client_stat(fid);
-	if (IS_ERR(st))
-		return ERR_CAST(st);
-
-	inode = v9fs_qid_iget(sb, &st->qid, st, new);
-	p9stat_free(st);
-	kfree(st);
-	return inode;
-}
-
 /**
  * v9fs_at_to_dotl_flags- convert Linux specific AT flags to
  * plan 9 AT flag.
@@ -633,7 +547,7 @@ v9fs_create(struct v9fs_session_info *v9ses, struct inode *dir,
 		/*
 		 * instantiate inode and assign the unopened fid to the dentry
 		 */
-		inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
+		inode = v9fs_get_inode_from_fid(v9ses, fid, dir->i_sb);
 		if (IS_ERR(inode)) {
 			err = PTR_ERR(inode);
 			p9_debug(P9_DEBUG_VFS,
@@ -761,10 +675,8 @@ struct dentry *v9fs_vfs_lookup(struct inode *dir, struct dentry *dentry,
 		inode = NULL;
 	else if (IS_ERR(fid))
 		inode = ERR_CAST(fid);
-	else if (v9ses->cache & (CACHE_META|CACHE_LOOSE))
-		inode = v9fs_get_inode_from_fid(v9ses, fid, dir->i_sb);
 	else
-		inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
+		inode = v9fs_get_inode_from_fid(v9ses, fid, dir->i_sb);
 	/*
 	 * If we had a rename on the server and a parallel lookup
 	 * for the new name, then make sure we instantiate with
@@ -1186,26 +1098,6 @@ v9fs_stat2inode(struct p9_wstat *stat, struct inode *inode,
 	v9inode->cache_validity &= ~V9FS_INO_INVALID_ATTR;
 }
 
-/**
- * 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