[PATCH] cifs: handle termination of cifs oplockd kernel thread

Signed-off-by: Steve French (sfrench@us.ibm.com)
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

4 files changed, 23 insertions, 15 deletions

diff --git a/fs/cifs/CHANGES b/fs/cifs/CHANGES
index 21a246473a9..bd3b55e1be1 100644
--- a/fs/cifs/CHANGES
+++ b/fs/cifs/CHANGES
@@ -1,6 +1,7 @@
 Version 1.34
 ------------
 Fix error mapping of the TOO_MANY_LINKS (hardlinks) case.
+Do not oops if user kills cifs oplock kernel thread.
 
 Version 1.33
 ------------
diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
index 6322aada491..8cc23e7d0d5 100644
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -835,6 +835,7 @@ static int cifs_oplock_thread(void * dummyarg)
 		}
 	} while(!signal_pending(current));
 	complete_and_exit (&cifs_oplock_exited, 0);
+	oplockThread = NULL;
 }
 
 static int __init
diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index e3b177a90b3..437be1efe99 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -384,7 +384,7 @@ cifs_demultiplex_thread(struct TCP_Server_Info *server)
 		if(server->tcpStatus == CifsExiting) {
 			break;
 		} else if (server->tcpStatus == CifsNeedReconnect) {
-			cFYI(1,("Reconnecting after server stopped responding"));
+			cFYI(1,("Reconnect after server stopped responding"));
 			cifs_reconnect(server);
 			cFYI(1,("call to reconnect done"));
 			csocket = server->ssocket;
@@ -396,7 +396,7 @@ cifs_demultiplex_thread(struct TCP_Server_Info *server)
 			continue;
 		} else if (length <= 0) {
 			if(server->tcpStatus == CifsNew) {
-				cFYI(1,("tcp session abended prematurely (after SMBnegprot)"));
+				cFYI(1,("tcp session abend after SMBnegprot"));
 				/* some servers kill the TCP session rather than
 				   returning an SMB negprot error, in which
 				   case reconnecting here is not going to help,
@@ -407,14 +407,15 @@ cifs_demultiplex_thread(struct TCP_Server_Info *server)
 				cFYI(1,("cifsd thread killed"));
 				break;
 			}
-			cFYI(1,("Reconnecting after unexpected peek error %d",length));
+			cFYI(1,("Reconnect after unexpected peek error %d",
+				length));
 			cifs_reconnect(server);
 			csocket = server->ssocket;
 			wake_up(&server->response_q);
 			continue;
 		} else if (length < 4) {
 			cFYI(1,
-			    ("Frame less than four bytes received  %d bytes long.",
+			    ("Frame under four bytes received (%d bytes long)",
 			      length));
 			cifs_reconnect(server);
 			csocket = server->ssocket;
@@ -593,7 +594,7 @@ multi_t2_fnd:
 					smallbuf = NULL;
 			}
 			wake_up_process(task_to_wake);
-		} else if ((is_valid_oplock_break(smb_buffer) == FALSE) 
+		} else if ((is_valid_oplock_break(smb_buffer) == FALSE)
 		    && (isMultiRsp == FALSE)) {                          
 			cERROR(1, ("No task to wake, unknown frame rcvd!"));
 			cifs_dump_mem("Received Data is: ",temp,sizeof(struct smb_hdr));
diff --git a/fs/cifs/misc.c b/fs/cifs/misc.c
index 75fd3bd6e23..db14b503d89 100644
--- a/fs/cifs/misc.c
+++ b/fs/cifs/misc.c
@@ -452,25 +452,30 @@ is_valid_oplock_break(struct smb_hdr *buf)
 			atomic_inc(&tcon->num_oplock_brks);
 #endif
 			list_for_each(tmp1,&tcon->openFileList){
-				netfile = list_entry(tmp1,struct cifsFileInfo,tlist);
+				netfile = list_entry(tmp1,struct cifsFileInfo,
+						     tlist);
 				if(pSMB->Fid == netfile->netfid) {
 					struct cifsInodeInfo *pCifsInode;
 					read_unlock(&GlobalSMBSeslock);
-					cFYI(1,("Matching file id, processing oplock break"));
+					cFYI(1,("file id match, oplock break"));
 					pCifsInode = 
 						CIFS_I(netfile->pInode);
 					pCifsInode->clientCanCacheAll = FALSE;
 					if(pSMB->OplockLevel == 0)
-						pCifsInode->clientCanCacheRead = FALSE;
+						pCifsInode->clientCanCacheRead
+							= FALSE;
 					pCifsInode->oplockPending = TRUE;
-					AllocOplockQEntry(netfile->pInode, netfile->netfid, tcon);
+					AllocOplockQEntry(netfile->pInode,
+							  netfile->netfid,
+							  tcon);
 					cFYI(1,("about to wake up oplock thd"));
-					wake_up_process(oplockThread);               
+					if(oplockThread)
+					    wake_up_process(oplockThread);
 					return TRUE;
 				}
 			}
 			read_unlock(&GlobalSMBSeslock);
-			cFYI(1,("No matching file for oplock break on connection"));
+			cFYI(1,("No matching file for oplock break"));
 			return TRUE;
 		}
 	}
@@ -491,7 +496,7 @@ dump_smb(struct smb_hdr *smb_buf, int smb_buf_length)
 
 	buffer = (unsigned char *) smb_buf;
 	for (i = 0, j = 0; i < smb_buf_length; i++, j++) {
-		if (i % 8 == 0) {	/* we have reached the beginning of line  */
+		if (i % 8 == 0) {	/* have reached the beginning of line */
 			printk(KERN_DEBUG "| ");
 			j = 0;
 		}
@@ -502,7 +507,7 @@ dump_smb(struct smb_hdr *smb_buf, int smb_buf_length)
 		else
 			debug_line[1 + (2 * j)] = '_';
 
-		if (i % 8 == 7) {	/* we have reached end of line, time to print ascii */
+		if (i % 8 == 7) { /* reached end of line, time to print ascii */
 			debug_line[16] = 0;
 			printk(" | %s\n", debug_line);
 		}
@@ -577,7 +582,7 @@ cifs_convertUCSpath(char *target, const __le16 * source, int maxlen,
 				}
 		}
 		j++;
-		/* check to make sure we do not overrun callers allocated temp buffer */
+		/* make sure we do not overrun callers allocated temp buffer */
 		if(j >= (2 * NAME_MAX))
 			break;
 	}
@@ -599,7 +604,7 @@ cifsConvertToUCS(__le16 * target, const char *source, int maxlen,
 	char src_char;
 
 	if(!mapChars) 
-		return cifs_strtoUCS((wchar_t *) target, source, PATH_MAX, cp);	
+		return cifs_strtoUCS((wchar_t *) target, source, PATH_MAX, cp);
 
 	for(i = 0, j = 0; i < maxlen; j++) {
 		src_char = source[i];