[PATCH] cifs: Ease memory pressure, do not use large buffers in byte range lock requests. (46810cbf) · Commits · e / devices / android_kernel_teracube_2e

fs/cifs/cifssmb.c

+5 −3

Original line number	Diff line number	Diff line
		@@ -1023,11 +1023,13 @@ CIFSSMBLock(const int xid, struct cifsTconInfo *tcon,
		__u16 count;

		cFYI(1, ("In CIFSSMBLock - timeout %d numLock %d",waitFlag,numLock));
		rc = smb_init(SMB_COM_LOCKING_ANDX, 8, tcon, (void **) &pSMB,
		(void **) &pSMBr);
		rc = small_smb_init(SMB_COM_LOCKING_ANDX, 8, tcon, (void **) &pSMB);

		if (rc)
		return rc;

		pSMBr = (LOCK_RSP )pSMB; / BB removeme BB */

		if(lockType == LOCKING_ANDX_OPLOCK_RELEASE) {
		timeout = -1; /* no response expected */
		pSMB->Timeout = 0;
		@@ -1065,7 +1067,7 @@ CIFSSMBLock(const int xid, struct cifsTconInfo *tcon,
		if (rc) {
		cFYI(1, ("Send error in Lock = %d", rc));
		}
		cifs_buf_release(pSMB);
		cifs_small_buf_release(pSMB);

		/* Note: On -EAGAIN error only caller can retry on handle based calls
		since file handle passed in no longer valid */

fs/cifs/connect.c

+149 −146

Original line number	Diff line number	Diff line
		@@ -294,21 +294,27 @@ cifs_demultiplex_thread(struct TCP_Server_Info *server)
		csocket = server->ssocket;
		wake_up(&server->response_q);
		continue;
		} else if (length > 3) {
		} else if (length < 4) {
		cFYI(1,
		("Frame less than four bytes received %d bytes long.",
		length));
		cifs_reconnect(server);
		csocket = server->ssocket;
		wake_up(&server->response_q);
		continue;
		}

		/* the right amount was read from socket - 4 bytes */

		pdu_length = ntohl(smb_buffer->smb_buf_length);
		/* Only read pdu_length after below checks for too short (due
		to e.g. int overflow) and too long ie beyond end of buf */
		cFYI(1,("rfc1002 length(big endian)0x%x)",
		pdu_length+4));
		cFYI(1,("rfc1002 length(big endian)0x%x)", pdu_length+4));

		temp = (char *) smb_buffer;
		if (temp[0] == (char) RFC1002_SESSION_KEEP_ALIVE) {
		cFYI(0,("Received 4 byte keep alive packet"));
		} else if (temp[0] ==
		(char) RFC1002_POSITIVE_SESSION_RESPONSE) {
		} else if (temp[0] == (char)RFC1002_POSITIVE_SESSION_RESPONSE) {
		cFYI(1,("Good RFC 1002 session rsp"));
		} else if (temp[0] ==
		(char)RFC1002_NEGATIVE_SESSION_RESPONSE) {
		} else if (temp[0] == (char)RFC1002_NEGATIVE_SESSION_RESPONSE) {
		/* we get this from Windows 98 instead of
		an error on SMB negprot response */
		cFYI(1,("Negative RFC 1002 Session Response Error 0x%x)",temp[4]));
		@@ -339,7 +345,7 @@ cifs_demultiplex_thread(struct TCP_Server_Info *server)
		cifs_reconnect(server);
		csocket = server->ssocket;
		continue;
		} else {
		} else { /* we have an SMB response */
		if((pdu_length > CIFSMaxBufSize +
		MAX_CIFS_HDR_SIZE - 4) \|\|
		(pdu_length < sizeof (struct smb_hdr) - 1 - 4)) {
		@@ -351,6 +357,8 @@ cifs_demultiplex_thread(struct TCP_Server_Info *server)
		wake_up(&server->response_q);
		continue;
		} else { /* length ok */
		int reconnect = 0;

		if(pdu_length > MAX_CIFS_HDR_SIZE - 4) {
		isLargeBuf = TRUE;
		memcpy(bigbuf, smallbuf, 4);
		@@ -368,14 +376,16 @@ cifs_demultiplex_thread(struct TCP_Server_Info *server)
		if((server->tcpStatus == CifsExiting) \|\|
		(length == -EINTR)) {
		/* then will exit */
		goto dmx_loop_end;
		reconnect = 2;
		break;
		} else if (server->tcpStatus ==
		CifsNeedReconnect) {
		cifs_reconnect(server);
		csocket = server->ssocket;
		/* Reconnect wakes up rspns q */
		/* Now we will reread sock */
		goto dmx_loop_end;
		reconnect = 1;
		break;
		} else if ((length == -ERESTARTSYS) \|\|
		(length == -EAGAIN)) {
		msleep(1); /* minimum sleep to prevent looping
		@@ -383,14 +393,19 @@ cifs_demultiplex_thread(struct TCP_Server_Info *server)
		tcpStatus CifsNeedReconnect if server hung */
		continue;
		} else if (length <= 0) {
		cERROR(1,
		("Received no data, expecting %d",
		cERROR(1,("Received no data, expecting %d",
		pdu_length - total_read));
		cifs_reconnect(server);
		csocket = server->ssocket;
		goto dmx_loop_end;
		reconnect = 1;
		break;
		}
		}
		if(reconnect == 2)
		break;
		else if(reconnect == 1)
		continue;

		length += 4; /* account for rfc1002 hdr */
		}

		@@ -401,13 +416,11 @@ cifs_demultiplex_thread(struct TCP_Server_Info *server)
		continue;
		}

		/* BB FIXME - add checkTrans2SMBSecondary() */

		task_to_wake = NULL;
		spin_lock(&GlobalMid_Lock);
		list_for_each(tmp, &server->pending_mid_q) {
		mid_entry = list_entry(tmp, struct
		mid_q_entry,
		mid_entry = list_entry(tmp, struct mid_q_entry,
		qhead);

		if ((mid_entry->mid == smb_buffer->Mid)
		@@ -417,6 +430,8 @@ cifs_demultiplex_thread(struct TCP_Server_Info *server)
		smb_buffer->Command)) {
		cFYI(1,("Found Mid 0x%x wake up"
		,mid_entry->mid));
		/* BB FIXME - missing code here BB */
		/* check_2nd_t2(smb_buffer); */
		task_to_wake = mid_entry->tsk;
		mid_entry->resp_buf =
		smb_buffer;
		@@ -441,18 +456,6 @@ cifs_demultiplex_thread(struct TCP_Server_Info *server)
		cifs_dump_mem("Received Data is: ",temp,sizeof(struct smb_hdr));
		}
		}
		} else {
		cFYI(1,
		("Frame less than four bytes received %d bytes long.",
		length));
		cifs_reconnect(server);
		csocket = server->ssocket;
		wake_up(&server->response_q);
		continue;
		}
		dmx_loop_end:
		cFYI(1,("Exiting cifsd loop"));

		}
		spin_lock(&GlobalMid_Lock);
		server->tcpStatus = CifsExiting;