[CIFS] Add in some missing flags and cifs README and TODO corrections

Signed-off-by: Steve French <sfrench@us.ibm.com>
diff --git a/fs/cifs/CHANGES b/fs/cifs/CHANGES
index a9b6bc5..b4d388d 100644
--- a/fs/cifs/CHANGES
+++ b/fs/cifs/CHANGES
@@ -8,7 +8,10 @@
 default uid and gid for files when they are certain that the uids or
 gids on the server do not match those of the client.  Make "sec=none"
 mount override username (so that null user connection is attempted)
-to match what documentation said.
+to match what documentation said. Support for very large reads, over 127K,
+available to some newer servers (such as Samba 3.0.26 and later but
+note that it also requires setting CIFSMaxBufSize at module install
+time to a larger value which may hurt performance in some cases).
 
 Version 1.48
 ------------
diff --git a/fs/cifs/README b/fs/cifs/README
index 4d01697..eb3efd5 100644
--- a/fs/cifs/README
+++ b/fs/cifs/README
@@ -301,10 +301,21 @@
 		during the local client kernel build will be used.
 		If server does not support Unicode, this parameter is
 		unused.
-  rsize		default read size (usually 16K)
-  wsize		default write size (usually 16K, 32K is often better over GigE)
-		maximum wsize currently allowed by CIFS is 57344 (14 4096 byte
-		pages)
+  rsize		default read size (usually 16K). The client currently
+		can not use rsize larger than CIFSMaxBufSize. CIFSMaxBufSize
+		defaults to 16K and may be changed (from 8K to the maximum
+		kmalloc size allowed by your kernel) at module install time
+		for cifs.ko. Setting CIFSMaxBufSize to a very large value
+		will cause cifs to use more memory and may reduce performance
+		in some cases.  To use rsize greater than 127K (the original
+		cifs protocol maximum) also requires that the server support
+		a new Unix Capability flag (for very large read) which some
+		newer servers (e.g. Samba 3.0.26 or later) do. rsize can be
+		set from a minimum of 2048 to a maximum of 130048 (127K or
+		CIFSMaxBufSize, whichever is smaller)
+  wsize		default write size (default 57344)
+		maximum wsize currently allowed by CIFS is 57344 (fourteen
+		4096 byte pages)
   rw		mount the network share read-write (note that the
 		server may still consider the share read-only)
   ro		mount network share read-only
@@ -582,10 +593,10 @@
 
 	echo 1 > /proc/fs/cifs/traceSMB
 
-Two other experimental features are under development and to test 
-require enabling CONFIG_CIFS_EXPERIMENTAL
+Two other experimental features are under development. To test these
+requires enabling CONFIG_CIFS_EXPERIMENTAL
 
-	More efficient write operations
+	ipv6 enablement
 
 	DNOTIFY fcntl: needed for support of directory change 
 			    notification and perhaps later for file leases)
diff --git a/fs/cifs/TODO b/fs/cifs/TODO
index 78b620e..d57dc29 100644
--- a/fs/cifs/TODO
+++ b/fs/cifs/TODO
@@ -106,6 +106,12 @@
 succeed but still return access denied (appears to be Windows 
 server not cifs client problem) and has not been reproduced recently.
 NTFS partitions do not have this problem.
+4) Unix/POSIX capabilities are reset after reconnection, and affect
+a few fields in the tree connection but we do do not know which
+superblocks to apply these changes to.  We should probably walk
+the list of superblocks to set these.  Also need to check the
+flags on the second mount to the same share, and see if we
+can do the same trick that NFS does to remount duplicate shares.
 
 Misc testing to do
 ==================
diff --git a/fs/cifs/cifspdu.h b/fs/cifs/cifspdu.h
index d619ca7..802d27d 100644
--- a/fs/cifs/cifspdu.h
+++ b/fs/cifs/cifspdu.h
@@ -712,6 +712,7 @@
 #define REQ_OPLOCK         0x00000002
 #define REQ_BATCHOPLOCK    0x00000004
 #define REQ_OPENDIRONLY    0x00000008
+#define REQ_EXTENDED_INFO  0x00000010
 
 typedef struct smb_com_open_req {	/* also handles create */
 	struct smb_hdr hdr;	/* wct = 24 */
@@ -1885,15 +1886,19 @@
 #define CIFS_UNIX_POSIX_PATHNAMES_CAP   0x00000010 /* Allow POSIX path chars  */
 #define CIFS_UNIX_POSIX_PATH_OPS_CAP    0x00000020 /* Allow new POSIX path based
 						      calls including posix open
-						      and posix unlink */ 
+						      and posix unlink */
+#define CIFS_UNIX_LARGE_READ_CAP        0x00000040 /* support reads >128K (up
+						      to 0xFFFF00 */				       
+#define CIFS_UNIX_LARGE_WRITE_CAP       0x00000080
+
 #ifdef CONFIG_CIFS_POSIX
 /* Can not set pathnames cap yet until we send new posix create SMB since
    otherwise server can treat such handles opened with older ntcreatex
    (by a new client which knows how to send posix path ops)
    as non-posix handles (can affect write behavior with byte range locks.
    We can add back in POSIX_PATH_OPS cap when Posix Create/Mkdir finished */
-/* #define CIFS_UNIX_CAP_MASK              0x0000003b */
-#define CIFS_UNIX_CAP_MASK              0x0000001b 
+/* #define CIFS_UNIX_CAP_MASK              0x000000fb */
+#define CIFS_UNIX_CAP_MASK              0x000000db 
 #else 
 #define CIFS_UNIX_CAP_MASK              0x00000013
 #endif /* CONFIG_CIFS_POSIX */
diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index f4e9266..4a2af78 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -1,7 +1,7 @@
 /*
  *   fs/cifs/connect.c
  *
- *   Copyright (C) International Business Machines  Corp., 2002,2006
+ *   Copyright (C) International Business Machines  Corp., 2002,2007
  *   Author(s): Steve French (sfrench@us.ibm.com)
  *
  *   This library is free software; you can redistribute it and/or modify
@@ -1650,19 +1650,19 @@
 		}
 		
 		cap &= CIFS_UNIX_CAP_MASK;
-		if(vol_info && vol_info->no_psx_acl)
+		if (vol_info && vol_info->no_psx_acl)
 			cap &= ~CIFS_UNIX_POSIX_ACL_CAP;
-		else if(CIFS_UNIX_POSIX_ACL_CAP & cap) {
+		else if (CIFS_UNIX_POSIX_ACL_CAP & cap) {
 			cFYI(1,("negotiated posix acl support"));
 			if(sb)
 				sb->s_flags |= MS_POSIXACL;
 		}
 
-		if(vol_info && vol_info->posix_paths == 0)
+		if (vol_info && vol_info->posix_paths == 0)
 			cap &= ~CIFS_UNIX_POSIX_PATHNAMES_CAP;
-		else if(cap & CIFS_UNIX_POSIX_PATHNAMES_CAP) {
+		else if (cap & CIFS_UNIX_POSIX_PATHNAMES_CAP) {
 			cFYI(1,("negotiate posix pathnames"));
-			if(sb)
+			if (sb)
 				CIFS_SB(sb)->mnt_cifs_flags |= 
 					CIFS_MOUNT_POSIX_PATHS;
 		}
@@ -1670,21 +1670,35 @@
 		/* We might be setting the path sep back to a different
 		form if we are reconnecting and the server switched its
 		posix path capability for this share */	
-		if(sb && (CIFS_SB(sb)->prepathlen > 0))
+		if (sb && (CIFS_SB(sb)->prepathlen > 0))
 			CIFS_SB(sb)->prepath[0] = CIFS_DIR_SEP(CIFS_SB(sb));
+
+		if (sb && (CIFS_SB(sb)->rsize > 127 * 1024)) {
+			if ((cap & CIFS_UNIX_LARGE_READ_CAP) == 0) {
+				CIFS_SB(sb)->rsize = 127 * 1024;
+#ifdef CONFIG_CIFS_DEBUG2
+				cFYI(1,("larger reads not supported by srv"));
+#endif
+			}
+		}
+		
 	
 		cFYI(1,("Negotiate caps 0x%x",(int)cap));
 #ifdef CONFIG_CIFS_DEBUG2
-		if(cap & CIFS_UNIX_FCNTL_CAP)
+		if (cap & CIFS_UNIX_FCNTL_CAP)
 			cFYI(1,("FCNTL cap"));
-		if(cap & CIFS_UNIX_EXTATTR_CAP)
+		if (cap & CIFS_UNIX_EXTATTR_CAP)
 			cFYI(1,("EXTATTR cap"));
-		if(cap & CIFS_UNIX_POSIX_PATHNAMES_CAP)
+		if (cap & CIFS_UNIX_POSIX_PATHNAMES_CAP)
 			cFYI(1,("POSIX path cap"));
-		if(cap & CIFS_UNIX_XATTR_CAP)
+		if (cap & CIFS_UNIX_XATTR_CAP)
 			cFYI(1,("XATTR cap"));
-		if(cap & CIFS_UNIX_POSIX_ACL_CAP)
+		if (cap & CIFS_UNIX_POSIX_ACL_CAP)
 			cFYI(1,("POSIX ACL cap"));
+		if (cap & CIFS_UNIX_LARGE_READ_CAP)
+			cFYI(1,("very large read cap"));
+		if (cap & CIFS_UNIX_LARGE_WRITE_CAP)
+			cFYI(1,("very large write cap"));
 #endif /* CIFS_DEBUG2 */
 		if (CIFSSMBSetFSUnixInfo(xid, tcon, cap)) {
 			cFYI(1,("setting capabilities failed"));
@@ -1935,13 +1949,14 @@
 			cERROR(1,("rsize %d too large, using MaxBufSize",
 				volume_info.rsize));
 			cifs_sb->rsize = CIFSMaxBufSize;
-		} else if((volume_info.rsize) && (volume_info.rsize <= CIFSMaxBufSize))
+		} else if ((volume_info.rsize) &&
+				(volume_info.rsize <= CIFSMaxBufSize))
 			cifs_sb->rsize = volume_info.rsize;
 		else /* default */
 			cifs_sb->rsize = CIFSMaxBufSize;
 
 		if (volume_info.wsize > PAGEVEC_SIZE * PAGE_CACHE_SIZE) {
-			cERROR(1,("wsize %d too large using 4096 instead",
+			cERROR(1,("wsize %d too large, using 4096 instead",
 				  volume_info.wsize));
 			cifs_sb->wsize = 4096;
 		} else if (volume_info.wsize)
@@ -1960,7 +1975,7 @@
 		if (cifs_sb->rsize < 2048) {
 			cifs_sb->rsize = 2048; 
 			/* Windows ME may prefer this */
-			cFYI(1,("readsize set to minimum 2048"));
+			cFYI(1,("readsize set to minimum: 2048"));
 		}
 		/* calculate prepath */
 		cifs_sb->prepath = volume_info.prepath;
@@ -2116,7 +2131,13 @@
 		/* tell server which Unix caps we support */
 		if (tcon->ses->capabilities & CAP_UNIX)
 			reset_cifs_unix_caps(xid, tcon, sb, &volume_info);
-		
+		else if(cifs_sb->rsize > (1024 * 127)) {
+			cifs_sb->rsize = 1024 * 127;
+#ifdef CONFIG_CIFS_DEBUG2
+			cFYI(1,("no very large read support, rsize 127K"));
+#endif
+			
+		}
 		if (!(tcon->ses->capabilities & CAP_LARGE_WRITE_X))
 			cifs_sb->wsize = min(cifs_sb->wsize,
 					     (tcon->ses->server->maxBuf -
diff --git a/fs/cifs/file.c b/fs/cifs/file.c
index 94d5b49..5f1b707 100644
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -1720,7 +1720,9 @@
 	pTcon = cifs_sb->tcon;
 
 	pagevec_init(&lru_pvec, 0);
-
+#ifdef CONFIG_CIFS_DEBUG2
+		cFYI(1,("rpages: num pages %d", num_pages));
+#endif	
 	for (i = 0; i < num_pages; ) {
 		unsigned contig_pages;
 		struct page *tmp_page;
@@ -1753,7 +1755,10 @@
 		/* Read size needs to be in multiples of one page */
 		read_size = min_t(const unsigned int, read_size,
 				  cifs_sb->rsize & PAGE_CACHE_MASK);
-
+#ifdef CONFIG_CIFS_DEBUG2
+		cFYI(1,("rpages: read size 0x%x  contiguous pages %d",
+				read_size, contig_pages));
+#endif		
 		rc = -EAGAIN;
 		while (rc == -EAGAIN) {
 			if ((open_file->invalidHandle) &&