Initial protocol definitions for cifs dirnotify (directory change notification) support

Signed-off-by: Steve French <sfrench@us.ibm.com>

fs/cifs/cifspdu.h

@@ -862,6 +862,10 @@ typedef struct smb_com_create_directory_rsp {
 	__u16 ByteCount;	/* bct = 0 */
 } CREATE_DIRECTORY_RSP;
 
+/***************************************************/
+/* NT Transact structure defintions follow         */
+/* Currently only ioctl and notify are implemented */
+/***************************************************/
 typedef struct smb_com_transaction_ioctl_req {
 	struct smb_hdr hdr;	/* wct = 23 */
 	__u8 MaxSetupCount;
@@ -904,29 +908,45 @@ typedef struct smb_com_transaction_ioctl_rsp {
 } TRANSACT_IOCTL_RSP;
 
 typedef struct smb_com_transaction_change_notify_req {
-        struct smb_hdr hdr;     /* wct = 23 */
-        __u8 MaxSetupCount;
-        __u16 Reserved;
-        __u32 TotalParameterCount;
-        __u32 TotalDataCount;
-        __u32 MaxParameterCount;
-        __u32 MaxDataCount;
-        __u32 ParameterCount;
-        __u32 ParameterOffset;
-        __u32 DataCount;
-        __u32 DataOffset;
-        __u8 SetupCount; /* four setup words follow subcommand */
-        /* SNIA spec incorrectly included spurious pad here */
-        __u16 SubCommand;/* 4 = Change Notify */
+	struct smb_hdr hdr;     /* wct = 23 */
+	__u8 MaxSetupCount;
+	__u16 Reserved;
+	__u32 TotalParameterCount;
+	__u32 TotalDataCount;
+	__u32 MaxParameterCount;
+	__u32 MaxDataCount;
+	__u32 ParameterCount;
+	__u32 ParameterOffset;
+	__u32 DataCount;
+	__u32 DataOffset;
+	__u8 SetupCount; /* four setup words follow subcommand */
+	/* SNIA spec incorrectly included spurious pad here */
+	__u16 SubCommand;/* 4 = Change Notify */
 	__u32 CompletionFilter;  /* operation to monitor */
 	__u16 Fid;
 	__u8 WatchTree;  /* 1 = Monitor subdirectories */
+	__u8 Reserved2;
 	__u16 ByteCount;
-	__u8 Pad[3];
-	__u8 Data[1];
+/* __u8 Pad[3];*/
+/*	__u8 Data[1];*/
 } TRANSACT_CHANGE_NOTIFY_REQ;
 
-/* Completion Filter flags */
+typedef struct smb_com_transaction_change_notify_rsp {
+	struct smb_hdr hdr;	/* wct = 18 */
+	__u8 Reserved[3];
+	__u32 TotalParameterCount;
+	__u32 TotalDataCount;
+	__u32 ParameterCount;
+	__u32 ParameterOffset;
+	__u32 ParameterDisplacement;
+	__u32 DataCount;
+	__u32 DataOffset;
+	__u32 DataDisplacement;
+	__u8 SetupCount;   /* 0 */
+	__u16 ByteCount;
+	/* __u8 Pad[3]; */
+} TRANSACT_CHANGE_NOTIFY_RSP;
+/* Completion Filter flags for Notify */
 #define FILE_NOTIFY_CHANGE_FILE_NAME    0x00000001
 #define FILE_NOTIFY_CHANGE_DIR_NAME     0x00000002
 #define FILE_NOTIFY_CHANGE_NAME         0x00000003

fs/cifs/cifsproto.h

@@ -244,4 +244,7 @@ extern int CIFSSMBCopy(int xid,
 			const __u16 target_tid,
 			const char *toName, const int flags,
 			const struct nls_table *nls_codepage);
+extern int CIFSSMBNotify(const int xid, struct cifsTconInfo *tcon, 
+			const int notify_subdirs,const __u16 netfid,__u32 filter,
+			const struct nls_table *nls_codepage);
 #endif			/* _CIFSPROTO_H */

fs/cifs/cifssmb.c

@@ -1436,9 +1436,9 @@ CIFSSMBQueryReparseLinkInfo(const int xid, struct cifsTconInfo *tcon,
 
 	pSMB->TotalParameterCount = 0 ;
 	pSMB->TotalDataCount = 0;
-	pSMB->MaxParameterCount = cpu_to_le16(2);
+	pSMB->MaxParameterCount = cpu_to_le32(2);
 	/* BB find exact data count max from sess structure BB */
-	pSMB->MaxDataCount = cpu_to_le16(4000);
+	pSMB->MaxDataCount = cpu_to_le32(4000);
 	pSMB->MaxSetupCount = 4;
 	pSMB->Reserved = 0;
 	pSMB->ParameterOffset = 0;
@@ -2786,3 +2786,51 @@ CIFSSMBUnixSetPerms(const int xid, struct cifsTconInfo *tcon,
 		goto setPermsRetry;
 	return rc;
 }
+
+int CIFSSMBNotify(const int xid, struct cifsTconInfo *tcon, 
+			const int notify_subdirs, const __u16 netfid,
+			__u32 filter, const struct nls_table *nls_codepage)
+{
+	int rc = 0;
+	struct smb_com_transaction_change_notify_req * pSMB = NULL;
+	struct smb_com_transaction_change_notify_rsp * pSMBr = NULL;
+	int bytes_returned;
+
+	cFYI(1, ("In CIFSSMBNotify for file handle %d",(int)netfid));
+	rc = smb_init(SMB_COM_NT_TRANSACT, 23, tcon, (void **) &pSMB,
+                      (void **) &pSMBr);
+	if (rc)
+		return rc;
+
+	pSMB->TotalParameterCount = 0 ;
+	pSMB->TotalDataCount = 0;
+	pSMB->MaxParameterCount = cpu_to_le32(2);
+	/* BB find exact data count max from sess structure BB */
+	pSMB->MaxDataCount = 0; /* same in little endian or be */
+	pSMB->MaxSetupCount = 4;
+	pSMB->Reserved = 0;
+	pSMB->ParameterOffset = 0;
+	pSMB->DataCount = 0;
+	pSMB->DataOffset = 0;
+	pSMB->SetupCount = 4; /* single byte does not need le conversion */
+	pSMB->SubCommand = cpu_to_le16(NT_TRANSACT_NOTIFY_CHANGE);
+	pSMB->ParameterCount = pSMB->TotalParameterCount;
+	if(notify_subdirs)
+		pSMB->WatchTree = 1; /* one byte - no le conversion needed */
+	pSMB->Reserved2 = 0;
+	pSMB->CompletionFilter = cpu_to_le32(filter);
+	pSMB->Fid = netfid; /* file handle always le */
+	pSMB->ByteCount = 0;
+
+	pSMB->hdr.smb_buf_length += pSMB->ByteCount;
+	rc = SendReceive(xid, tcon->ses, (struct smb_hdr *) pSMB,
+			(struct smb_hdr *) pSMBr, &bytes_returned, 0);
+	if (rc) {
+		cFYI(1, ("Error in Notify = %d", rc));
+	}
+	if (pSMB)
+		cifs_buf_release(pSMB);
+/*		if (rc == -EAGAIN)
+			goto NotifyRetry; */
+	return rc;	
+}

fs/cifs/fcntl.c

@@ -32,9 +32,12 @@ int cifs_directory_notify(unsigned long arg, struct file * file)
 {
 	int xid;
 	int rc = -EINVAL;
+	int oplock = FALSE;
 	struct cifs_sb_info *cifs_sb;
 	struct cifsTconInfo *pTcon;
 	char *full_path = NULL;
+	__u32 filter = FILE_NOTIFY_CHANGE_NAME | FILE_NOTIFY_CHANGE_ATTRIBUTES;
+    __u16 netfid;
 
 	xid = GetXid();
 	cifs_sb = CIFS_SB(file->f_dentry->d_sb);
@@ -44,7 +47,20 @@ int cifs_directory_notify(unsigned long arg, struct file * file)
 		rc = -ENOMEM;
 	} else {
 		cFYI(1,("cifs dir notify on file %s",full_path));
-		/* CIFSSMBNotify(xid, pTcon, full_path, cifs_sb->local_nls);*/
+		rc = CIFSSMBOpen(xid, pTcon, full_path, FILE_OPEN, 
+			GENERIC_READ | SYNCHRONIZE, 0 /* create options */,
+			&netfid, &oplock,NULL, cifs_sb->local_nls);
+		/* BB fixme - add this handle to a notify handle list */
+		if(rc) {
+			cFYI(1,("Could not open directory for notify"));
+		} else {
+			rc = CIFSSMBNotify(xid, pTcon, 1 /* subdirs */, netfid, 
+				filter, cifs_sb->local_nls);
+			/* BB add code to close file eventually (at unmount
+			it would close automatically but may be a way
+			to do it easily when inode freed or when
+			notify info is cleared/changed */
+		}
 	}
 	
 	FreeXid(xid);