[CIFS] Legacy time handling for Win9x and OS/2 part 1

Signed-off-by: Steve French <sfrench@us.ibm.com>
diff --git a/fs/cifs/cifsproto.h b/fs/cifs/cifsproto.h
index b35c55c..2fbc982 100644
--- a/fs/cifs/cifsproto.h
+++ b/fs/cifs/cifsproto.h
@@ -80,6 +80,9 @@
 extern void DeleteOplockQEntry(struct oplock_q_entry *);
 extern struct timespec cifs_NTtimeToUnix(u64 /* utc nanoseconds since 1601 */ );
 extern u64 cifs_UnixTimeToNT(struct timespec);
+extern __le64 cnvrtDosCifsTm(__u16 date, __u16 time);
+extern struct timespec cnvrtDosUnixTm(__u16 date, __u16 time);
+
 extern int cifs_get_inode_info(struct inode **pinode,
 			const unsigned char *search_path, 
 			FILE_ALL_INFO * pfile_info,
diff --git a/fs/cifs/cifssmb.c b/fs/cifs/cifssmb.c
index 075d8fb..2851d6e 100644
--- a/fs/cifs/cifssmb.c
+++ b/fs/cifs/cifssmb.c
@@ -2856,7 +2856,6 @@
 	return rc;
 }
 
-
 /* Legacy Query Path Information call for lookup to old servers such
    as Win9x/WinME */
 int SMBQueryInformation(const int xid, struct cifsTconInfo *tcon,
@@ -2898,7 +2897,16 @@
 	if (rc) {
 		cFYI(1, ("Send error in QueryInfo = %d", rc));
 	} else if (pFinfo) {            /* decode response */
+		struct timespec ts;
+		__u32 time = le32_to_cpu(pSMBr->last_write_time);
+		/* BB FIXME - add time zone adjustment BB */
 		memset(pFinfo, 0, sizeof(FILE_ALL_INFO));
+		ts.tv_nsec = 0;
+		ts.tv_sec = time;
+		/* decode time fields */
+		pFinfo->ChangeTime = cifs_UnixTimeToNT(ts);
+		pFinfo->LastWriteTime = pFinfo->ChangeTime;
+		pFinfo->LastAccessTime = 0;
 		pFinfo->AllocationSize =
 			cpu_to_le64(le32_to_cpu(pSMBr->size));
 		pFinfo->EndOfFile = pFinfo->AllocationSize;
diff --git a/fs/cifs/inode.c b/fs/cifs/inode.c
index b88147c..06dbce3 100644
--- a/fs/cifs/inode.c
+++ b/fs/cifs/inode.c
@@ -432,8 +432,11 @@
 		(pTcon->ses->server->maxBuf - MAX_CIFS_HDR_SIZE) & 0xFFFFFE00;*/
 
 		/* Linux can not store file creation time so ignore it */
-		inode->i_atime =
-		    cifs_NTtimeToUnix(le64_to_cpu(pfindData->LastAccessTime));
+		if(pfindData->LastAccessTime)
+			inode->i_atime = cifs_NTtimeToUnix
+				(le64_to_cpu(pfindData->LastAccessTime));
+		else /* do not need to use current_fs_time - time not stored */
+			inode->i_atime = CURRENT_TIME;
 		inode->i_mtime =
 		    cifs_NTtimeToUnix(le64_to_cpu(pfindData->LastWriteTime));
 		inode->i_ctime =
diff --git a/fs/cifs/link.c b/fs/cifs/link.c
index a57f5d6..0bee8b7 100644
--- a/fs/cifs/link.c
+++ b/fs/cifs/link.c
@@ -254,7 +254,11 @@
 				tmpbuffer,
 				len - 1,
 				cifs_sb->local_nls);
-	else {
+	else if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_UNX_EMUL) {
+		cERROR(1,("SFU style symlinks not implemented yet"));
+		/* add open and read as in fs/cifs/inode.c */
+	
+	} else {
 		rc = CIFSSMBOpen(xid, pTcon, full_path, FILE_OPEN, GENERIC_READ,
 				OPEN_REPARSE_POINT,&fid, &oplock, NULL, 
 				cifs_sb->local_nls, 
diff --git a/fs/cifs/netmisc.c b/fs/cifs/netmisc.c
index ce87550..fa5124d 100644
--- a/fs/cifs/netmisc.c
+++ b/fs/cifs/netmisc.c
@@ -909,3 +909,54 @@
 	/* Convert to 100ns intervals and then add the NTFS time offset. */
 	return (u64) t.tv_sec * 10000000 + t.tv_nsec/100 + NTFS_TIME_OFFSET;
 }
+
+static int total_days_of_prev_months[] =
+{0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334};
+
+
+__le64 cnvrtDosCifsTm(__u16 date, __u16 time)
+{
+	return cpu_to_le64(cifs_UnixTimeToNT(cnvrtDosUnixTm(date, time)));
+}
+struct timespec cnvrtDosUnixTm(__u16 date, __u16 time)
+{
+	__u8  dt[2];
+	__u8  tm[2];
+	struct timespec ts;
+	int sec,min, days, month, year;
+	struct timespec removeme; /* BB removeme BB */
+/*	SMB_TIME * st = (SMB_TIME *)&time;*/
+
+	cFYI(1,("date %d time %d",date, time));
+
+	dt[0] = date & 0xFF;
+	dt[1] = (date & 0xFF00) >> 8;
+	tm[0] = time & 0xFF;
+	tm[1] = (time & 0xFF00) >> 8;
+
+	sec = tm[0] & 0x1F;
+	sec = 2 * sec;
+	min = ((tm[0] >>5)&0xFF) + ((tm[1] & 0x7)<<3);
+
+	sec += (min * 60);
+	sec += 60 * 60 * ((tm[1] >> 3) &0xFF) /* hours */;
+	days = (dt[0] & 0x1F) - 1;
+	month = ((dt[0] >> 5) & 0xFF) + ((dt[1] & 0x1) <<3);
+	if(month > 12)
+		cERROR(1,("illegal month %d in date", month));
+	month -= 1;
+	days += total_days_of_prev_months[month];
+	days += 3653; /* account for difference in days between 1980 and 1970 */
+	year = (dt[1]>>1) & 0xFF;
+	days += year * 365;
+	days += (year/4); /* leap year */
+	/* adjust for leap year where we are still before leap day */
+	days -= ((year & 0x03) == 0) && (month < 2 ? 1 : 0);
+	sec += 24 * 60 * 60 * days; 
+
+	removeme = CURRENT_TIME; /* BB removeme BB */
+	ts.tv_sec = sec;
+
+	ts.tv_nsec = 0;
+	return ts;
+} 
diff --git a/fs/cifs/readdir.c b/fs/cifs/readdir.c
index 9aeb58a..71e86c3 100644
--- a/fs/cifs/readdir.c
+++ b/fs/cifs/readdir.c
@@ -135,12 +135,19 @@
 		tmp_inode->i_ctime =
 		      cifs_NTtimeToUnix(le64_to_cpu(pfindData->ChangeTime));
 	} else { /* legacy, OS2 and DOS style */
+/*		struct timespec ts;*/
 		FIND_FILE_STANDARD_INFO * pfindData = 
 			(FIND_FILE_STANDARD_INFO *)buf;
 
+/*		ts = cnvrtDosUnixTm(
+				le16_to_cpu(pfindData->LastWriteDate),
+				le16_to_cpu(pfindData->LastWriteTime));*/
 		attr = le16_to_cpu(pfindData->Attributes);
 		allocation_size = le32_to_cpu(pfindData->AllocationSize);
 		end_of_file = le32_to_cpu(pfindData->DataSize);
+		/* do not need to use current_fs_time helper function since
+		 time not stored for this case so atime can not "go backwards"
+		 by pulling newer older from disk when inode refrenshed */
 		tmp_inode->i_atime = CURRENT_TIME;
 		/* tmp_inode->i_mtime =  BB FIXME - add dos time handling
 		tmp_inode->i_ctime = 0;   BB FIXME */