From: Rohith Surabattula <rohiths@microsoft.com>
Date: Tue, 16 Feb 2021 10:40:45 +0000
Subject: [PATCH] TCON Reconnect during STATUS_NETWORK_NAME_DELETED
Git-commit: 9e550b085206544bd03a8b1dd58a5414e9508351
References: bsc#1190317
Patch-mainline: v5.12-rc1

When server returns error STATUS_NETWORK_NAME_DELETED, TCON
must be marked for reconnect. So, subsequent IO does the tree
connect again.

Signed-off-by: Rohith Surabattula <rohiths@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Acked-by: Enzo Matsumiya <ematsumiya@suse.de>
---
 fs/cifs/cifsglob.h |  2 ++
 fs/cifs/connect.c  |  4 ++++
 fs/cifs/smb2ops.c  | 41 +++++++++++++++++++++++++++++++++++++++++
 3 files changed, 47 insertions(+)

diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
index fb904236f07f..3de3c5908a72 100644
--- a/fs/cifs/cifsglob.h
+++ b/fs/cifs/cifsglob.h
@@ -505,6 +505,8 @@ struct smb_version_operations {
 	loff_t (*llseek)(struct file *, struct cifs_tcon *, loff_t, int);
 	/* Check for STATUS_IO_TIMEOUT */
 	bool (*is_status_io_timeout)(char *buf);
+	/* Check for STATUS_NETWORK_NAME_DELETED */
+	void (*is_network_name_deleted)(char *buf, struct TCP_Server_Info *srv);
 };
 
 struct smb_version_values {
diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index 139e306305df..cd6dbeaf2166 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -995,6 +995,10 @@ cifs_demultiplex_thread(void *p)
 			if (mids[i] != NULL) {
 				mids[i]->resp_buf_size = server->pdu_size;
 
+				if (bufs[i] && server->ops->is_network_name_deleted)
+					server->ops->is_network_name_deleted(bufs[i],
+									server);
+
 				if (!mids[i]->multiRsp || mids[i]->multiEnd)
 					mids[i]->callback(mids[i]);
 
diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c
index fe171ccbe8e3..807ecd444c16 100644
--- a/fs/cifs/smb2ops.c
+++ b/fs/cifs/smb2ops.c
@@ -2451,6 +2451,33 @@ smb2_is_status_io_timeout(char *buf)
 		return false;
 }
 
+static void
+smb2_is_network_name_deleted(char *buf, struct TCP_Server_Info *server)
+{
+	struct smb2_sync_hdr *shdr = (struct smb2_sync_hdr *)buf;
+	struct list_head *tmp, *tmp1;
+	struct cifs_ses *ses;
+	struct cifs_tcon *tcon;
+
+	if (shdr->Status == STATUS_NETWORK_NAME_DELETED) {
+		spin_lock(&cifs_tcp_ses_lock);
+		list_for_each(tmp, &server->smb_ses_list) {
+			ses = list_entry(tmp, struct cifs_ses, smb_ses_list);
+			list_for_each(tmp1, &ses->tcon_list) {
+				tcon = list_entry(tmp1, struct cifs_tcon, tcon_list);
+				if (tcon->tid == shdr->TreeId) {
+					tcon->need_reconnect = true;
+					spin_unlock(&cifs_tcp_ses_lock);
+					pr_warn_once("Server share %s deleted.\n",
+						     tcon->treeName);
+					return;
+				}
+			}
+		}
+		spin_unlock(&cifs_tcp_ses_lock);
+	}
+}
+
 static int
 smb2_oplock_response(struct cifs_tcon *tcon, struct cifs_fid *fid,
 		     struct cifsInodeInfo *cinode)
@@ -4638,6 +4665,10 @@ static void smb2_decrypt_offload(struct work_struct *work)
 #ifdef CONFIG_CIFS_STATS2
 			mid->when_received = jiffies;
 #endif
+			if (dw->server->ops->is_network_name_deleted)
+				dw->server->ops->is_network_name_deleted(dw->buf,
+									 dw->server);
+
 			mid->callback(mid);
 		} else {
 			spin_lock(&GlobalMid_Lock);
@@ -4756,6 +4787,12 @@ receive_encrypted_read(struct TCP_Server_Info *server, struct mid_q_entry **mid,
 		rc = handle_read_data(server, *mid, buf,
 				      server->vals->read_rsp_size,
 				      pages, npages, len, false);
+		if (rc >= 0) {
+			if (server->ops->is_network_name_deleted) {
+				server->ops->is_network_name_deleted(buf,
+								server);
+			}
+		}
 	}
 
 free_pages:
@@ -5105,6 +5142,7 @@ struct smb_version_operations smb20_operations = {
 	.fiemap = smb3_fiemap,
 	.llseek = smb3_llseek,
 	.is_status_io_timeout = smb2_is_status_io_timeout,
+	.is_network_name_deleted = smb2_is_network_name_deleted,
 };
 
 struct smb_version_operations smb21_operations = {
@@ -5206,6 +5244,7 @@ struct smb_version_operations smb21_operations = {
 	.fiemap = smb3_fiemap,
 	.llseek = smb3_llseek,
 	.is_status_io_timeout = smb2_is_status_io_timeout,
+	.is_network_name_deleted = smb2_is_network_name_deleted,
 };
 
 struct smb_version_operations smb30_operations = {
@@ -5319,6 +5358,7 @@ struct smb_version_operations smb30_operations = {
 	.fiemap = smb3_fiemap,
 	.llseek = smb3_llseek,
 	.is_status_io_timeout = smb2_is_status_io_timeout,
+	.is_network_name_deleted = smb2_is_network_name_deleted,
 };
 
 struct smb_version_operations smb311_operations = {
@@ -5432,6 +5472,7 @@ struct smb_version_operations smb311_operations = {
 	.fiemap = smb3_fiemap,
 	.llseek = smb3_llseek,
 	.is_status_io_timeout = smb2_is_status_io_timeout,
+	.is_network_name_deleted = smb2_is_network_name_deleted,
 };
 
 struct smb_version_values smb20_values = {
-- 
2.33.0