Merge tag 'v4.19.31' into v4.19-rt

This is the 4.19.31 stable release

 Conflicts:
	mm/swap.c

6 files changed, 82 insertions, 14 deletions

diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
index 9dcaed031843..80f33582059e 100644
--- a/fs/cifs/cifsglob.h
+++ b/fs/cifs/cifsglob.h
@@ -235,6 +235,8 @@ struct smb_version_operations {
 	int * (*get_credits_field)(struct TCP_Server_Info *, const int);
 	unsigned int (*get_credits)(struct mid_q_entry *);
 	__u64 (*get_next_mid)(struct TCP_Server_Info *);
+	void (*revert_current_mid)(struct TCP_Server_Info *server,
+				   const unsigned int val);
 	/* data offset from read response message */
 	unsigned int (*read_data_offset)(char *);
 	/*
@@ -756,6 +758,22 @@ get_next_mid(struct TCP_Server_Info *server)
 	return cpu_to_le16(mid);
 }
 
+static inline void
+revert_current_mid(struct TCP_Server_Info *server, const unsigned int val)
+{
+	if (server->ops->revert_current_mid)
+		server->ops->revert_current_mid(server, val);
+}
+
+static inline void
+revert_current_mid_from_hdr(struct TCP_Server_Info *server,
+			    const struct smb2_sync_hdr *shdr)
+{
+	unsigned int num = le16_to_cpu(shdr->CreditCharge);
+
+	return revert_current_mid(server, num > 0 ? num : 1);
+}
+
 static inline __u16
 get_mid(const struct smb_hdr *smb)
 {
@@ -1391,6 +1409,7 @@ struct mid_q_entry {
 	struct kref refcount;
 	struct TCP_Server_Info *server;	/* server corresponding to this mid */
 	__u64 mid;		/* multiplex id */
+	__u16 credits;		/* number of credits consumed by this mid */
 	__u32 pid;		/* process id */
 	__u32 sequence_number;  /* for CIFS signing */
 	unsigned long when_alloc;  /* when mid was created */
diff --git a/fs/cifs/file.c b/fs/cifs/file.c
index 23db881daab5..08761a6a039d 100644
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -2871,14 +2871,16 @@ cifs_strict_writev(struct kiocb *iocb, struct iov_iter *from)
 	 * these pages but not on the region from pos to ppos+len-1.
 	 */
 	written = cifs_user_writev(iocb, from);
-	if (written > 0 && CIFS_CACHE_READ(cinode)) {
+	if (CIFS_CACHE_READ(cinode)) {
 		/*
-		 * Windows 7 server can delay breaking level2 oplock if a write
-		 * request comes - break it on the client to prevent reading
-		 * an old data.
+		 * We have read level caching and we have just sent a write
+		 * request to the server thus making data in the cache stale.
+		 * Zap the cache and set oplock/lease level to NONE to avoid
+		 * reading stale data from the cache. All subsequent read
+		 * operations will read new data from the server.
 		 */
 		cifs_zap_mapping(inode);
-		cifs_dbg(FYI, "Set no oplock for inode=%p after a write operation\n",
+		cifs_dbg(FYI, "Set Oplock/Lease to NONE for inode=%p after write\n",
 			 inode);
 		cinode->oplock = 0;
 	}
diff --git a/fs/cifs/smb2misc.c b/fs/cifs/smb2misc.c
index 7b8b58fb4d3f..58700d2ba8cd 100644
--- a/fs/cifs/smb2misc.c
+++ b/fs/cifs/smb2misc.c
@@ -517,7 +517,6 @@ smb2_tcon_has_lease(struct cifs_tcon *tcon, struct smb2_lease_break *rsp,
 	__u8 lease_state;
 	struct list_head *tmp;
 	struct cifsFileInfo *cfile;
-	struct TCP_Server_Info *server = tcon->ses->server;
 	struct cifs_pending_open *open;
 	struct cifsInodeInfo *cinode;
 	int ack_req = le32_to_cpu(rsp->Flags &
@@ -537,13 +536,25 @@ smb2_tcon_has_lease(struct cifs_tcon *tcon, struct smb2_lease_break *rsp,
 		cifs_dbg(FYI, "lease key match, lease break 0x%x\n",
 			 le32_to_cpu(rsp->NewLeaseState));
 
-		server->ops->set_oplock_level(cinode, lease_state, 0, NULL);
-
 		if (ack_req)
 			cfile->oplock_break_cancelled = false;
 		else
 			cfile->oplock_break_cancelled = true;
 
+		set_bit(CIFS_INODE_PENDING_OPLOCK_BREAK, &cinode->flags);
+
+		/*
+		 * Set or clear flags depending on the lease state being READ.
+		 * HANDLE caching flag should be added when the client starts
+		 * to defer closing remote file handles with HANDLE leases.
+		 */
+		if (lease_state & SMB2_LEASE_READ_CACHING_HE)
+			set_bit(CIFS_INODE_DOWNGRADE_OPLOCK_TO_L2,
+				&cinode->flags);
+		else
+			clear_bit(CIFS_INODE_DOWNGRADE_OPLOCK_TO_L2,
+				  &cinode->flags);
+
 		queue_work(cifsoplockd_wq, &cfile->oplock_break);
 		kfree(lw);
 		return true;
diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c
index 237d7281ada3..d4d7d61a6fe2 100644
--- a/fs/cifs/smb2ops.c
+++ b/fs/cifs/smb2ops.c
@@ -204,6 +204,15 @@ smb2_get_next_mid(struct TCP_Server_Info *server)
 	return mid;
 }
 
+static void
+smb2_revert_current_mid(struct TCP_Server_Info *server, const unsigned int val)
+{
+	spin_lock(&GlobalMid_Lock);
+	if (server->CurrentMid >= val)
+		server->CurrentMid -= val;
+	spin_unlock(&GlobalMid_Lock);
+}
+
 static struct mid_q_entry *
 smb2_find_mid(struct TCP_Server_Info *server, char *buf)
 {
@@ -2301,6 +2310,15 @@ smb2_downgrade_oplock(struct TCP_Server_Info *server,
 }
 
 static void
+smb21_downgrade_oplock(struct TCP_Server_Info *server,
+		       struct cifsInodeInfo *cinode, bool set_level2)
+{
+	server->ops->set_oplock_level(cinode,
+				      set_level2 ? SMB2_LEASE_READ_CACHING_HE :
+				      0, 0, NULL);
+}
+
+static void
 smb2_set_oplock_level(struct cifsInodeInfo *cinode, __u32 oplock,
 		      unsigned int epoch, bool *purge_cache)
 {
@@ -3247,6 +3265,7 @@ struct smb_version_operations smb20_operations = {
 	.get_credits = smb2_get_credits,
 	.wait_mtu_credits = cifs_wait_mtu_credits,
 	.get_next_mid = smb2_get_next_mid,
+	.revert_current_mid = smb2_revert_current_mid,
 	.read_data_offset = smb2_read_data_offset,
 	.read_data_length = smb2_read_data_length,
 	.map_error = map_smb2_to_linux_error,
@@ -3341,6 +3360,7 @@ struct smb_version_operations smb21_operations = {
 	.get_credits = smb2_get_credits,
 	.wait_mtu_credits = smb2_wait_mtu_credits,
 	.get_next_mid = smb2_get_next_mid,
+	.revert_current_mid = smb2_revert_current_mid,
 	.read_data_offset = smb2_read_data_offset,
 	.read_data_length = smb2_read_data_length,
 	.map_error = map_smb2_to_linux_error,
@@ -3351,7 +3371,7 @@ struct smb_version_operations smb21_operations = {
 	.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,
+	.downgrade_oplock = smb21_downgrade_oplock,
 	.need_neg = smb2_need_neg,
 	.negotiate = smb2_negotiate,
 	.negotiate_wsize = smb2_negotiate_wsize,
@@ -3436,6 +3456,7 @@ struct smb_version_operations smb30_operations = {
 	.get_credits = smb2_get_credits,
 	.wait_mtu_credits = smb2_wait_mtu_credits,
 	.get_next_mid = smb2_get_next_mid,
+	.revert_current_mid = smb2_revert_current_mid,
 	.read_data_offset = smb2_read_data_offset,
 	.read_data_length = smb2_read_data_length,
 	.map_error = map_smb2_to_linux_error,
@@ -3447,7 +3468,7 @@ struct smb_version_operations smb30_operations = {
 	.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,
+	.downgrade_oplock = smb21_downgrade_oplock,
 	.need_neg = smb2_need_neg,
 	.negotiate = smb2_negotiate,
 	.negotiate_wsize = smb2_negotiate_wsize,
@@ -3540,6 +3561,7 @@ struct smb_version_operations smb311_operations = {
 	.get_credits = smb2_get_credits,
 	.wait_mtu_credits = smb2_wait_mtu_credits,
 	.get_next_mid = smb2_get_next_mid,
+	.revert_current_mid = smb2_revert_current_mid,
 	.read_data_offset = smb2_read_data_offset,
 	.read_data_length = smb2_read_data_length,
 	.map_error = map_smb2_to_linux_error,
@@ -3551,7 +3573,7 @@ struct smb_version_operations smb311_operations = {
 	.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,
+	.downgrade_oplock = smb21_downgrade_oplock,
 	.need_neg = smb2_need_neg,
 	.negotiate = smb2_negotiate,
 	.negotiate_wsize = smb2_negotiate_wsize,
diff --git a/fs/cifs/smb2transport.c b/fs/cifs/smb2transport.c
index 7b351c65ee46..63264db78b89 100644
--- a/fs/cifs/smb2transport.c
+++ b/fs/cifs/smb2transport.c
@@ -576,6 +576,7 @@ smb2_mid_entry_alloc(const struct smb2_sync_hdr *shdr,
 		     struct TCP_Server_Info *server)
 {
 	struct mid_q_entry *temp;
+	unsigned int credits = le16_to_cpu(shdr->CreditCharge);
 
 	if (server == NULL) {
 		cifs_dbg(VFS, "Null TCP session in smb2_mid_entry_alloc\n");
@@ -586,6 +587,7 @@ smb2_mid_entry_alloc(const struct smb2_sync_hdr *shdr,
 	memset(temp, 0, sizeof(struct mid_q_entry));
 	kref_init(&temp->refcount);
 	temp->mid = le64_to_cpu(shdr->MessageId);
+	temp->credits = credits > 0 ? credits : 1;
 	temp->pid = current->pid;
 	temp->command = shdr->Command; /* Always LE */
 	temp->when_alloc = jiffies;
@@ -674,13 +676,18 @@ smb2_setup_request(struct cifs_ses *ses, struct smb_rqst *rqst)
 	smb2_seq_num_into_buf(ses->server, shdr);
 
 	rc = smb2_get_mid_entry(ses, shdr, &mid);
-	if (rc)
+	if (rc) {
+		revert_current_mid_from_hdr(ses->server, shdr);
 		return ERR_PTR(rc);
+	}
+
 	rc = smb2_sign_rqst(rqst, ses->server);
 	if (rc) {
+		revert_current_mid_from_hdr(ses->server, shdr);
 		cifs_delete_mid(mid);
 		return ERR_PTR(rc);
 	}
+
 	return mid;
 }
 
@@ -695,11 +702,14 @@ smb2_setup_async_request(struct TCP_Server_Info *server, struct smb_rqst *rqst)
 	smb2_seq_num_into_buf(server, shdr);
 
 	mid = smb2_mid_entry_alloc(shdr, server);
-	if (mid == NULL)
+	if (mid == NULL) {
+		revert_current_mid_from_hdr(server, shdr);
 		return ERR_PTR(-ENOMEM);
+	}
 
 	rc = smb2_sign_rqst(rqst, server);
 	if (rc) {
+		revert_current_mid_from_hdr(server, shdr);
 		DeleteMidQEntry(mid);
 		return ERR_PTR(rc);
 	}
diff --git a/fs/cifs/transport.c b/fs/cifs/transport.c
index 66348b3d28e6..f2938bd95c40 100644
--- a/fs/cifs/transport.c
+++ b/fs/cifs/transport.c
@@ -638,6 +638,7 @@ cifs_call_async(struct TCP_Server_Info *server, struct smb_rqst *rqst,
 	cifs_in_send_dec(server);
 
 	if (rc < 0) {
+		revert_current_mid(server, mid->credits);
 		server->sequence_number -= 2;
 		cifs_delete_mid(mid);
 	}
@@ -842,6 +843,7 @@ compound_send_recv(const unsigned int xid, struct cifs_ses *ses,
 	for (i = 0; i < num_rqst; i++) {
 		midQ[i] = ses->server->ops->setup_request(ses, &rqst[i]);
 		if (IS_ERR(midQ[i])) {
+			revert_current_mid(ses->server, i);
 			for (j = 0; j < i; j++)
 				cifs_delete_mid(midQ[j]);
 			mutex_unlock(&ses->server->srv_mutex);
@@ -867,8 +869,10 @@ compound_send_recv(const unsigned int xid, struct cifs_ses *ses,
 	for (i = 0; i < num_rqst; i++)
 		cifs_save_when_sent(midQ[i]);
 
-	if (rc < 0)
+	if (rc < 0) {
+		revert_current_mid(ses->server, num_rqst);
 		ses->server->sequence_number -= 2;
+	}
 
 	mutex_unlock(&ses->server->srv_mutex);