Revert "Handle mismatched open calls"

BugLink: http://bugs.launchpad.net/bugs/1670508

This reverts commit 35067b7f.

The revert is in favor of cherry-picking the upstream commit, so the
rest of the patchset can apply.
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>

fs/cifs/cifsglob.h

@@ -227,7 +227,6 @@ struct smb_version_operations {
 	/* verify the message */
 	int (*check_message)(char *, unsigned int);
 	bool (*is_oplock_break)(char *, struct TCP_Server_Info *);
-	int (*handle_cancelled_mid)(char *, struct TCP_Server_Info *);
 	void (*downgrade_oplock)(struct TCP_Server_Info *,
 					struct cifsInodeInfo *, bool);
 	/* process transaction2 response */
@@ -1290,19 +1289,12 @@ struct mid_q_entry {
 	void *callback_data;	  /* general purpose pointer for callback */
 	void *resp_buf;		/* pointer to received SMB header */
 	int mid_state;	/* wish this were enum but can not pass to wait_event */
-	unsigned int mid_flags;
 	__le16 command;		/* smb command code */
 	bool large_buf:1;	/* if valid response, is pointer to large buf */
 	bool multiRsp:1;	/* multiple trans2 responses for one request  */
 	bool multiEnd:1;	/* both received */
 };
 
-struct close_cancelled_open {
-	struct cifs_fid         fid;
-	struct cifs_tcon        *tcon;
-	struct work_struct      work;
-};
-
 /*	Make code in transport.c a little cleaner by moving
 	update of optional stats into function below */
 #ifdef CONFIG_CIFS_STATS2
@@ -1434,9 +1426,6 @@ static inline void free_dfs_info_array(struct dfs_info3_param *param,
 #define   MID_RESPONSE_MALFORMED 0x10
 #define   MID_SHUTDOWN		 0x20
 
-/* Flags */
-#define   MID_WAIT_CANCELLED	 1 /* Cancelled while waiting for response */
-
 /* Types of response buffer returned from SendReceive2 */
 #define   CIFS_NO_BUFFER        0    /* Response buffer not returned */
 #define   CIFS_SMALL_BUFFER     1

fs/cifs/cifssmb.c

@@ -1427,8 +1427,6 @@ cifs_readv_discard(struct TCP_Server_Info *server, struct mid_q_entry *mid)
 
 	length = discard_remaining_data(server);
 	dequeue_mid(mid, rdata->result);
-	mid->resp_buf = server->smallbuf;
-	server->smallbuf = NULL;
 	return length;
 }
 
@@ -1543,8 +1541,6 @@ cifs_readv_receive(struct TCP_Server_Info *server, struct mid_q_entry *mid)
 		return cifs_readv_discard(server, mid);
 
 	dequeue_mid(mid, false);
-	mid->resp_buf = server->smallbuf;
-	server->smallbuf = NULL;
 	return length;
 }
 

fs/cifs/connect.c

@@ -936,19 +936,10 @@ cifs_demultiplex_thread(void *p)
 
 		server->lstrp = jiffies;
 		if (mid_entry != NULL) {
-			if ((mid_entry->mid_flags & MID_WAIT_CANCELLED) &&
-			     mid_entry->mid_state == MID_RESPONSE_RECEIVED &&
-					server->ops->handle_cancelled_mid)
-				server->ops->handle_cancelled_mid(
-							mid_entry->resp_buf,
-							server);
-
 			if (!mid_entry->multiRsp || mid_entry->multiEnd)
 				mid_entry->callback(mid_entry);
-		} else if (server->ops->is_oplock_break &&
-			   server->ops->is_oplock_break(buf, server)) {
-			cifs_dbg(FYI, "Received oplock break\n");
-		} else {
+		} else if (!server->ops->is_oplock_break ||
+			   !server->ops->is_oplock_break(buf, server)) {
 			cifs_dbg(VFS, "No task to wake, unknown frame received! NumMids %d\n",
 				 atomic_read(&midCount));
 			cifs_dump_mem("Received Data is: ", buf,

fs/cifs/smb2misc.c

@@ -630,47 +630,3 @@ smb2_is_valid_oplock_break(char *buffer, struct TCP_Server_Info *server)
 	cifs_dbg(FYI, "Can not process oplock break for non-existent connection\n");
 	return false;
 }
-
-void
-smb2_cancelled_close_fid(struct work_struct *work)
-{
-	struct close_cancelled_open *cancelled = container_of(work,
-					struct close_cancelled_open, work);
-
-	cifs_dbg(VFS, "Close unmatched open\n");
-
-	SMB2_close(0, cancelled->tcon, cancelled->fid.persistent_fid,
-		   cancelled->fid.volatile_fid);
-	cifs_put_tcon(cancelled->tcon);
-	kfree(cancelled);
-}
-
-int
-smb2_handle_cancelled_mid(char *buffer, struct TCP_Server_Info *server)
-{
-	struct smb2_hdr *hdr = (struct smb2_hdr *)buffer;
-	struct smb2_create_rsp *rsp = (struct smb2_create_rsp *)buffer;
-	struct cifs_tcon *tcon;
-	struct close_cancelled_open *cancelled;
-
-	if (hdr->Command != SMB2_CREATE || hdr->Status != STATUS_SUCCESS)
-		return 0;
-
-	cancelled = kzalloc(sizeof(*cancelled), GFP_KERNEL);
-	if (!cancelled)
-		return -ENOMEM;
-
-	tcon = smb2_find_smb_tcon(server, hdr->SessionId, hdr->TreeId);
-	if (!tcon) {
-		kfree(cancelled);
-		return -ENOENT;
-	}
-
-	cancelled->fid.persistent_fid = rsp->PersistentFileId;
-	cancelled->fid.volatile_fid = rsp->VolatileFileId;
-	cancelled->tcon = tcon;
-	INIT_WORK(&cancelled->work, smb2_cancelled_close_fid);
-	queue_work(cifsiod_wq, &cancelled->work);
-
-	return 0;
-}

fs/cifs/smb2ops.c

@@ -1511,7 +1511,6 @@ struct smb_version_operations smb20_operations = {
 	.clear_stats = smb2_clear_stats,
 	.print_stats = smb2_print_stats,
 	.is_oplock_break = smb2_is_valid_oplock_break,
-	.handle_cancelled_mid = smb2_handle_cancelled_mid,
 	.downgrade_oplock = smb2_downgrade_oplock,
 	.need_neg = smb2_need_neg,
 	.negotiate = smb2_negotiate,
@@ -1590,7 +1589,6 @@ struct smb_version_operations smb21_operations = {
 	.clear_stats = smb2_clear_stats,
 	.print_stats = smb2_print_stats,
 	.is_oplock_break = smb2_is_valid_oplock_break,
-	.handle_cancelled_mid = smb2_handle_cancelled_mid,
 	.downgrade_oplock = smb2_downgrade_oplock,
 	.need_neg = smb2_need_neg,
 	.negotiate = smb2_negotiate,
@@ -1672,7 +1670,6 @@ struct smb_version_operations smb30_operations = {
 	.print_stats = smb2_print_stats,
 	.dump_share_caps = smb2_dump_share_caps,
 	.is_oplock_break = smb2_is_valid_oplock_break,
-	.handle_cancelled_mid = smb2_handle_cancelled_mid,
 	.downgrade_oplock = smb2_downgrade_oplock,
 	.need_neg = smb2_need_neg,
 	.negotiate = smb2_negotiate,
@@ -1760,7 +1757,6 @@ struct smb_version_operations smb311_operations = {
 	.print_stats = smb2_print_stats,
 	.dump_share_caps = smb2_dump_share_caps,
 	.is_oplock_break = smb2_is_valid_oplock_break,
-	.handle_cancelled_mid = smb2_handle_cancelled_mid,
 	.downgrade_oplock = smb2_downgrade_oplock,
 	.need_neg = smb2_need_neg,
 	.negotiate = smb2_negotiate,

fs/cifs/smb2proto.h

@@ -47,10 +47,6 @@ extern struct mid_q_entry *smb2_setup_request(struct cifs_ses *ses,
 			      struct smb_rqst *rqst);
 extern struct mid_q_entry *smb2_setup_async_request(
 			struct TCP_Server_Info *server, struct smb_rqst *rqst);
-extern struct cifs_ses *smb2_find_smb_ses(struct TCP_Server_Info *server,
-					   __u64 ses_id);
-extern struct cifs_tcon *smb2_find_smb_tcon(struct TCP_Server_Info *server,
-						__u64 ses_id, __u32  tid);
 extern int smb2_calc_signature(struct smb_rqst *rqst,
 				struct TCP_Server_Info *server);
 extern int smb3_calc_signature(struct smb_rqst *rqst,
@@ -161,9 +157,6 @@ extern int SMB2_set_compression(const unsigned int xid, struct cifs_tcon *tcon,
 extern int SMB2_oplock_break(const unsigned int xid, struct cifs_tcon *tcon,
 			     const u64 persistent_fid, const u64 volatile_fid,
 			     const __u8 oplock_level);
-extern int smb2_handle_cancelled_mid(char *buffer,
-					struct TCP_Server_Info *server);
-void smb2_cancelled_close_fid(struct work_struct *work);
 extern int SMB2_QFS_info(const unsigned int xid, struct cifs_tcon *tcon,
 			 u64 persistent_file_id, u64 volatile_file_id,
 			 struct kstatfs *FSData);

fs/cifs/smb2transport.c

@@ -115,68 +115,22 @@ smb3_crypto_shash_allocate(struct TCP_Server_Info *server)
 }
 
 static struct cifs_ses *
-smb2_find_smb_ses_unlocked(struct TCP_Server_Info *server, __u64 ses_id)
+smb2_find_smb_ses(struct smb2_hdr *smb2hdr, struct TCP_Server_Info *server)
 {
 	struct cifs_ses *ses;
 
+	spin_lock(&cifs_tcp_ses_lock);
 	list_for_each_entry(ses, &server->smb_ses_list, smb_ses_list) {
-		if (ses->Suid != ses_id)
+		if (ses->Suid != smb2hdr->SessionId)
 			continue;
-		return ses;
-	}
-
-	return NULL;
-}
-
-struct cifs_ses *
-smb2_find_smb_ses(struct TCP_Server_Info *server, __u64 ses_id)
-{
-	struct cifs_ses *ses;
-
-	spin_lock(&cifs_tcp_ses_lock);
-	ses = smb2_find_smb_ses_unlocked(server, ses_id);
 		spin_unlock(&cifs_tcp_ses_lock);
-
 		return ses;
-}
-
-static struct cifs_tcon *
-smb2_find_smb_sess_tcon_unlocked(struct cifs_ses *ses, __u32  tid)
-{
-	struct cifs_tcon *tcon;
-
-	list_for_each_entry(tcon, &ses->tcon_list, tcon_list) {
-		if (tcon->tid != tid)
-			continue;
-		++tcon->tc_count;
-		return tcon;
 	}
+	spin_unlock(&cifs_tcp_ses_lock);
 
 	return NULL;
 }
 
-/*
- * Obtain tcon corresponding to the tid in the given
- * cifs_ses
- */
-
-struct cifs_tcon *
-smb2_find_smb_tcon(struct TCP_Server_Info *server, __u64 ses_id, __u32 tid)
-{
-	struct cifs_ses *ses;
-	struct cifs_tcon *tcon;
-
-	spin_lock(&cifs_tcp_ses_lock);
-	ses = smb2_find_smb_ses_unlocked(server, ses_id);
-	if (!ses) {
-		spin_unlock(&cifs_tcp_ses_lock);
-		return NULL;
-	}
-	tcon = smb2_find_smb_sess_tcon_unlocked(ses, tid);
-	spin_unlock(&cifs_tcp_ses_lock);
-
-	return tcon;
-}
 
 int
 smb2_calc_signature(struct smb_rqst *rqst, struct TCP_Server_Info *server)
@@ -189,7 +143,7 @@ smb2_calc_signature(struct smb_rqst *rqst, struct TCP_Server_Info *server)
 	struct smb2_hdr *smb2_pdu = (struct smb2_hdr *)iov[0].iov_base;
 	struct cifs_ses *ses;
 
-	ses = smb2_find_smb_ses(server, smb2_pdu->SessionId);
+	ses = smb2_find_smb_ses(smb2_pdu, server);
 	if (!ses) {
 		cifs_dbg(VFS, "%s: Could not find session\n", __func__);
 		return 0;
@@ -360,7 +314,7 @@ smb3_calc_signature(struct smb_rqst *rqst, struct TCP_Server_Info *server)
 	struct smb2_hdr *smb2_pdu = (struct smb2_hdr *)iov[0].iov_base;
 	struct cifs_ses *ses;
 
-	ses = smb2_find_smb_ses(server, smb2_pdu->SessionId);
+	ses = smb2_find_smb_ses(smb2_pdu, server);
 	if (!ses) {
 		cifs_dbg(VFS, "%s: Could not find session\n", __func__);
 		return 0;

fs/cifs/transport.c

@@ -786,11 +786,9 @@ SendReceive2(const unsigned int xid, struct cifs_ses *ses,
 
 	rc = wait_for_response(ses->server, midQ);
 	if (rc != 0) {
-		cifs_dbg(FYI, "Cancelling wait for mid %llu\n",	midQ->mid);
 		send_cancel(ses->server, buf, midQ);
 		spin_lock(&GlobalMid_Lock);
 		if (midQ->mid_state == MID_REQUEST_SUBMITTED) {
-			midQ->mid_flags |= MID_WAIT_CANCELLED;
 			midQ->callback = DeleteMidQEntry;
 			spin_unlock(&GlobalMid_Lock);
 			cifs_small_buf_release(buf);