--- zzzz-none-000/linux-3.10.107/fs/nfsd/fault_inject.c	2017-06-27 09:49:32.000000000 +0000
+++ scorpion-7490-727/linux-3.10.107/fs/nfsd/fault_inject.c	2021-02-04 17:41:59.000000000 +0000
@@ -17,105 +17,27 @@
 
 struct nfsd_fault_inject_op {
 	char *file;
-	u64 (*forget)(struct nfs4_client *, u64);
-	u64 (*print)(struct nfs4_client *, u64);
+	u64 (*get)(void);
+	u64 (*set_val)(u64);
+	u64 (*set_clnt)(struct sockaddr_storage *, size_t);
 };
 
-static struct nfsd_fault_inject_op inject_ops[] = {
-	{
-		.file   = "forget_clients",
-		.forget = nfsd_forget_client,
-		.print  = nfsd_print_client,
-	},
-	{
-		.file   = "forget_locks",
-		.forget = nfsd_forget_client_locks,
-		.print  = nfsd_print_client_locks,
-	},
-	{
-		.file   = "forget_openowners",
-		.forget = nfsd_forget_client_openowners,
-		.print  = nfsd_print_client_openowners,
-	},
-	{
-		.file   = "forget_delegations",
-		.forget = nfsd_forget_client_delegations,
-		.print  = nfsd_print_client_delegations,
-	},
-	{
-		.file   = "recall_delegations",
-		.forget = nfsd_recall_client_delegations,
-		.print  = nfsd_print_client_delegations,
-	},
-};
-
-static long int NUM_INJECT_OPS = sizeof(inject_ops) / sizeof(struct nfsd_fault_inject_op);
 static struct dentry *debug_dir;
 
-static void nfsd_inject_set(struct nfsd_fault_inject_op *op, u64 val)
-{
-	u64 count = 0;
-
-	if (val == 0)
-		printk(KERN_INFO "NFSD Fault Injection: %s (all)", op->file);
-	else
-		printk(KERN_INFO "NFSD Fault Injection: %s (n = %llu)", op->file, val);
-
-	nfs4_lock_state();
-	count = nfsd_for_n_state(val, op->forget);
-	nfs4_unlock_state();
-	printk(KERN_INFO "NFSD: %s: found %llu", op->file, count);
-}
-
-static void nfsd_inject_set_client(struct nfsd_fault_inject_op *op,
-				   struct sockaddr_storage *addr,
-				   size_t addr_size)
-{
-	char buf[INET6_ADDRSTRLEN];
-	struct nfs4_client *clp;
-	u64 count;
-
-	nfs4_lock_state();
-	clp = nfsd_find_client(addr, addr_size);
-	if (clp) {
-		count = op->forget(clp, 0);
-		rpc_ntop((struct sockaddr *)&clp->cl_addr, buf, sizeof(buf));
-		printk(KERN_INFO "NFSD [%s]: Client %s had %llu state object(s)\n", op->file, buf, count);
-	}
-	nfs4_unlock_state();
-}
-
-static void nfsd_inject_get(struct nfsd_fault_inject_op *op, u64 *val)
-{
-	nfs4_lock_state();
-	*val = nfsd_for_n_state(0, op->print);
-	nfs4_unlock_state();
-}
-
 static ssize_t fault_inject_read(struct file *file, char __user *buf,
 				 size_t len, loff_t *ppos)
 {
 	static u64 val;
 	char read_buf[25];
-	size_t size, ret;
+	size_t size;
 	loff_t pos = *ppos;
+	struct nfsd_fault_inject_op *op = file_inode(file)->i_private;
 
 	if (!pos)
-		nfsd_inject_get(file_inode(file)->i_private, &val);
+		val = op->get();
 	size = scnprintf(read_buf, sizeof(read_buf), "%llu\n", val);
 
-	if (pos < 0)
-		return -EINVAL;
-	if (pos >= size || !len)
-		return 0;
-	if (len > size - pos)
-		len = size - pos;
-	ret = copy_to_user(buf, read_buf + pos, len);
-	if (ret == len)
-		return -EFAULT;
-	len -= ret;
-	*ppos = pos + len;
-	return len;
+	return simple_read_from_buffer(buf, len, ppos, read_buf, size);
 }
 
 static ssize_t fault_inject_write(struct file *file, const char __user *buf,
@@ -125,18 +47,36 @@
 	size_t size = min(sizeof(write_buf) - 1, len);
 	struct net *net = current->nsproxy->net_ns;
 	struct sockaddr_storage sa;
+	struct nfsd_fault_inject_op *op = file_inode(file)->i_private;
 	u64 val;
+	char *nl;
 
 	if (copy_from_user(write_buf, buf, size))
 		return -EFAULT;
 	write_buf[size] = '\0';
 
+	/* Deal with any embedded newlines in the string */
+	nl = strchr(write_buf, '\n');
+	if (nl) {
+		size = nl - write_buf;
+		*nl = '\0';
+	}
+
 	size = rpc_pton(net, write_buf, size, (struct sockaddr *)&sa, sizeof(sa));
-	if (size > 0)
-		nfsd_inject_set_client(file_inode(file)->i_private, &sa, size);
-	else {
+	if (size > 0) {
+		val = op->set_clnt(&sa, size);
+		if (val)
+			pr_info("NFSD [%s]: Client %s had %llu state object(s)\n",
+				op->file, write_buf, val);
+	} else {
 		val = simple_strtoll(write_buf, NULL, 0);
-		nfsd_inject_set(file_inode(file)->i_private, val);
+		if (val == 0)
+			pr_info("NFSD Fault Injection: %s (all)", op->file);
+		else
+			pr_info("NFSD Fault Injection: %s (n = %llu)",
+				op->file, val);
+		val = op->set_val(val);
+		pr_info("NFSD: %s: found %llu", op->file, val);
 	}
 	return len; /* on success, claim we got the whole input */
 }
@@ -152,6 +92,41 @@
 	debugfs_remove_recursive(debug_dir);
 }
 
+static struct nfsd_fault_inject_op inject_ops[] = {
+	{
+		.file     = "forget_clients",
+		.get	  = nfsd_inject_print_clients,
+		.set_val  = nfsd_inject_forget_clients,
+		.set_clnt = nfsd_inject_forget_client,
+	},
+	{
+		.file     = "forget_locks",
+		.get	  = nfsd_inject_print_locks,
+		.set_val  = nfsd_inject_forget_locks,
+		.set_clnt = nfsd_inject_forget_client_locks,
+	},
+	{
+		.file     = "forget_openowners",
+		.get	  = nfsd_inject_print_openowners,
+		.set_val  = nfsd_inject_forget_openowners,
+		.set_clnt = nfsd_inject_forget_client_openowners,
+	},
+	{
+		.file     = "forget_delegations",
+		.get	  = nfsd_inject_print_delegations,
+		.set_val  = nfsd_inject_forget_delegations,
+		.set_clnt = nfsd_inject_forget_client_delegations,
+	},
+	{
+		.file     = "recall_delegations",
+		.get	  = nfsd_inject_print_delegations,
+		.set_val  = nfsd_inject_recall_delegations,
+		.set_clnt = nfsd_inject_recall_client_delegations,
+	},
+};
+
+#define NUM_INJECT_OPS (sizeof(inject_ops)/sizeof(struct nfsd_fault_inject_op))
+
 int nfsd_fault_inject_init(void)
 {
 	unsigned int i;