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

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

6 files changed, 80 insertions, 29 deletions

diff --git a/fs/cifs/CHANGES b/fs/cifs/CHANGES
index a9b6bc5157b8..b4d388d2b524 100644
--- a/fs/cifs/CHANGES
+++ b/fs/cifs/CHANGES
@@ -8,7 +8,10 @@ when Unix Extensions were ignored).  This allows users to override the
 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 4d01697722cc..eb3efd5a6a81 100644
--- a/fs/cifs/README
+++ b/fs/cifs/README
@@ -301,10 +301,21 @@ A partial list of the supported mount options follows:
                 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 @@ the start of smb requests and responses can be enabled via:
 
         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 78b620e332bd..d57dc2917d04 100644
--- a/fs/cifs/TODO
+++ b/fs/cifs/TODO
@@ -106,6 +106,12 @@ but recognizes them
 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 d619ca7d1416..802d27d98e2d 100644
--- a/fs/cifs/cifspdu.h
+++ b/fs/cifs/cifspdu.h
@@ -712,6 +712,7 @@ typedef struct smb_com_findclose_req {
 #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 @@ typedef struct {
 #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 f4e92661b223..4a2af78083fb 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 @@ void reset_cifs_unix_caps(int xid, struct cifsTconInfo * tcon,
                 }
                 
                 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 @@ void reset_cifs_unix_caps(int xid, struct cifsTconInfo * tcon,
                 /* 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 @@ cifs_mount(struct super_block *sb, struct cifs_sb_info *cifs_sb,
                         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 @@ cifs_mount(struct super_block *sb, struct cifs_sb_info *cifs_sb,
                 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 @@ cifs_mount(struct super_block *sb, struct cifs_sb_info *cifs_sb,
                 /* 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 94d5b49049df..5f1b707188f8 100644
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -1720,7 +1720,9 @@ static int cifs_readpages(struct file *file, struct address_space *mapping,
         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 @@ static int cifs_readpages(struct file *file, struct address_space *mapping,
                 /* 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) &&