Merge branch 'for-linus' of git://git.samba.org/sfrench/cifs-2.6

Pull CIFS fixes from Steve French:
"Small set of cifs fixes. Most important is Jeff's fix that works
around disconnection problems which can be caused by simultaneous use
of user space tools (starting a long running smbclient backup then
doing a cifs kernel mount) or multiple cifs mounts through a NAT, and
Jim's fix to deal with reexport of cifs share.

I expect to send two more cifs fixes next week (being tested now) -
fixes to address an SMB2 unmount hang when server dies and a fix for
cifs symlink handling of Windows "NFS" symlinks"

* 'for-linus' of git://git.samba.org/sfrench/cifs-2.6:
[CIFS] update cifs.ko version
[CIFS] Remove ext2 flags that have been moved to fs.h
[CIFS] Provide sane values for nlink
cifs: stop trying to use virtual circuits
CIFS: FS-Cache: Uncache unread pages in cifs_readpages() before freeing them

fs/cifs/cifsfs.h

···
 extern const struct export_operations cifs_export_ops;
 #endif /* CONFIG_CIFS_NFSD_EXPORT */
 
-#define CIFS_VERSION   "2.01"
+#define CIFS_VERSION   "2.02"
 #endif				/* _CIFSFS_H */

fs/cifs/cifsglob.h

···
 	unsigned int max_rw;	/* maxRw specifies the maximum */
 	/* message size the server can send or receive for */
 	/* SMB_COM_WRITE_RAW or SMB_COM_READ_RAW. */
-	unsigned int max_vcs;	/* maximum number of smb sessions, at least
-				   those that can be specified uniquely with
-				   vcnumbers */
 	unsigned int capabilities; /* selective disabling of caps by smb sess */
 	int timeAdj;  /* Adjust for difference in server time zone in sec */
 	__u64 CurrentMid;         /* multiplex id - rotating counter */
···
 	enum statusEnum status;
 	unsigned overrideSecFlg;  /* if non-zero override global sec flags */
 	__u16 ipc_tid;		/* special tid for connection to IPC share */
-	__u16 vcnum;
 	char *serverOS;		/* name of operating system underlying server */
 	char *serverNOS;	/* name of network operating system of server */
 	char *serverDomain;	/* security realm of server */
···
 #define CIFS_FATTR_DELETE_PENDING	0x2
 #define CIFS_FATTR_NEED_REVAL		0x4
 #define CIFS_FATTR_INO_COLLISION	0x8
+#define CIFS_FATTR_UNKNOWN_NLINK	0x10
 
 struct cifs_fattr {
 	u32		cf_flags;

fs/cifs/cifspdu.h

···
 } __attribute__((packed)) FILE_XATTR_INFO; /* extended attribute info
 					      level 0x205 */
 
-
-/* flags for chattr command */
-#define EXT_SECURE_DELETE		0x00000001 /* EXT3_SECRM_FL */
-#define EXT_ENABLE_UNDELETE		0x00000002 /* EXT3_UNRM_FL */
-/* Reserved for compress file 0x4 */
-#define EXT_SYNCHRONOUS			0x00000008 /* EXT3_SYNC_FL */
-#define EXT_IMMUTABLE_FL		0x00000010 /* EXT3_IMMUTABLE_FL */
-#define EXT_OPEN_APPEND_ONLY		0x00000020 /* EXT3_APPEND_FL */
-#define EXT_DO_NOT_BACKUP		0x00000040 /* EXT3_NODUMP_FL */
-#define EXT_NO_UPDATE_ATIME		0x00000080 /* EXT3_NOATIME_FL */
-/* 0x100 through 0x800 reserved for compression flags and are GET-ONLY */
-#define EXT_HASH_TREE_INDEXED_DIR	0x00001000 /* GET-ONLY EXT3_INDEX_FL */
-/* 0x2000 reserved for IMAGIC_FL */
-#define EXT_JOURNAL_THIS_FILE	0x00004000 /* GET-ONLY EXT3_JOURNAL_DATA_FL */
-/* 0x8000 reserved for EXT3_NOTAIL_FL */
-#define EXT_SYNCHRONOUS_DIR		0x00010000 /* EXT3_DIRSYNC_FL */
-#define EXT_TOPDIR			0x00020000 /* EXT3_TOPDIR_FL */
-
-#define EXT_SET_MASK			0x000300FF
-#define EXT_GET_MASK			0x0003DFFF
+/* flags for lsattr and chflags commands removed arein uapi/linux/fs.h */
 
 typedef struct file_chattr_info {
 	__le64	mask; /* list of all possible attribute bits */

fs/cifs/cifssmb.c

···
 			       cifs_max_pending);
 	set_credits(server, server->maxReq);
 	server->maxBuf = le16_to_cpu(rsp->MaxBufSize);
-	server->max_vcs = le16_to_cpu(rsp->MaxNumberVcs);
 	/* even though we do not use raw we might as well set this
 	accurately, in case we ever find a need for it */
 	if ((le16_to_cpu(rsp->RawMode) & RAW_ENABLE) == RAW_ENABLE) {

fs/cifs/file.c

···
 	/*
 	 * Reads as many pages as possible from fscache. Returns -ENOBUFS
 	 * immediately if the cookie is negative
+	 *
+	 * After this point, every page in the list might have PG_fscache set,
+	 * so we will need to clean that up off of every page we don't use.
 	 */
 	rc = cifs_readpages_from_fscache(mapping->host, mapping, page_list,
 					 &num_pages);
···
 		kref_put(&rdata->refcount, cifs_readdata_release);
 	}
 
+	/* Any pages that have been shown to fscache but didn't get added to
+	 * the pagecache must be uncached before they get returned to the
+	 * allocator.
+	 */
+	cifs_fscache_readpages_cancel(mapping->host, page_list);
 	return rc;
 }
 

fs/cifs/fscache.c

···
 		fscache_uncache_page(CIFS_I(inode)->fscache, page);
 }
 
+void __cifs_fscache_readpages_cancel(struct inode *inode, struct list_head *pages)
+{
+	cifs_dbg(FYI, "%s: (fsc: %p, i: %p)\n",
+		 __func__, CIFS_I(inode)->fscache, inode);
+	fscache_readpages_cancel(CIFS_I(inode)->fscache, pages);
+}
+
 void __cifs_fscache_invalidate_page(struct page *page, struct inode *inode)
 {
 	struct cifsInodeInfo *cifsi = CIFS_I(inode);

fs/cifs/fscache.h

···
 					 struct address_space *,
 					 struct list_head *,
 					 unsigned *);
+extern void __cifs_fscache_readpages_cancel(struct inode *, struct list_head *);
 
 extern void __cifs_readpage_to_fscache(struct inode *, struct page *);
 
···
 {
 	if (PageFsCache(page))
 		__cifs_readpage_to_fscache(inode, page);
+}
+
+static inline void cifs_fscache_readpages_cancel(struct inode *inode,
+						 struct list_head *pages)
+{
+	if (CIFS_I(inode)->fscache)
+		return __cifs_fscache_readpages_cancel(inode, pages);
 }
 
 #else /* CONFIG_CIFS_FSCACHE */
···
 
 static inline void cifs_readpage_to_fscache(struct inode *inode,
 			struct page *page) {}
+
+static inline void cifs_fscache_readpages_cancel(struct inode *inode,
+						 struct list_head *pages)
+{
+}
 
 #endif /* CONFIG_CIFS_FSCACHE */
 

fs/cifs/inode.c

···
 	cifs_i->invalid_mapping = true;
 }
 
+/*
+ * copy nlink to the inode, unless it wasn't provided.  Provide
+ * sane values if we don't have an existing one and none was provided
+ */
+static void
+cifs_nlink_fattr_to_inode(struct inode *inode, struct cifs_fattr *fattr)
+{
+	/*
+	 * if we're in a situation where we can't trust what we
+	 * got from the server (readdir, some non-unix cases)
+	 * fake reasonable values
+	 */
+	if (fattr->cf_flags & CIFS_FATTR_UNKNOWN_NLINK) {
+		/* only provide fake values on a new inode */
+		if (inode->i_state & I_NEW) {
+			if (fattr->cf_cifsattrs & ATTR_DIRECTORY)
+				set_nlink(inode, 2);
+			else
+				set_nlink(inode, 1);
+		}
+		return;
+	}
+
+	/* we trust the server, so update it */
+	set_nlink(inode, fattr->cf_nlink);
+}
+
 /* populate an inode with info from a cifs_fattr struct */
 void
 cifs_fattr_to_inode(struct inode *inode, struct cifs_fattr *fattr)
···
 	inode->i_mtime = fattr->cf_mtime;
 	inode->i_ctime = fattr->cf_ctime;
 	inode->i_rdev = fattr->cf_rdev;
-	set_nlink(inode, fattr->cf_nlink);
+	cifs_nlink_fattr_to_inode(inode, fattr);
 	inode->i_uid = fattr->cf_uid;
 	inode->i_gid = fattr->cf_gid;
 
···
 	fattr->cf_bytes = le64_to_cpu(info->AllocationSize);
 	fattr->cf_createtime = le64_to_cpu(info->CreationTime);
 
+	fattr->cf_nlink = le32_to_cpu(info->NumberOfLinks);
 	if (fattr->cf_cifsattrs & ATTR_DIRECTORY) {
 		fattr->cf_mode = S_IFDIR | cifs_sb->mnt_dir_mode;
 		fattr->cf_dtype = DT_DIR;
···
 		 * Server can return wrong NumberOfLinks value for directories
 		 * when Unix extensions are disabled - fake it.
 		 */
-		fattr->cf_nlink = 2;
+		if (!tcon->unix_ext)
+			fattr->cf_flags |= CIFS_FATTR_UNKNOWN_NLINK;
 	} else if (fattr->cf_cifsattrs & ATTR_REPARSE) {
 		fattr->cf_mode = S_IFLNK;
 		fattr->cf_dtype = DT_LNK;
···
 		if (fattr->cf_cifsattrs & ATTR_READONLY)
 			fattr->cf_mode &= ~(S_IWUGO);
 
-		fattr->cf_nlink = le32_to_cpu(info->NumberOfLinks);
-		if (fattr->cf_nlink < 1) {
-			cifs_dbg(1, "replacing bogus file nlink value %u\n",
+		/*
+		 * Don't accept zero nlink from non-unix servers unless
+		 * delete is pending.  Instead mark it as unknown.
+		 */
+		if ((fattr->cf_nlink < 1) && !tcon->unix_ext &&
+		    !info->DeletePending) {
+			cifs_dbg(1, "bogus file nlink value %u\n",
 				fattr->cf_nlink);
-			fattr->cf_nlink = 1;
+			fattr->cf_flags |= CIFS_FATTR_UNKNOWN_NLINK;
 		}
 	}
 

fs/cifs/readdir.c

···
 		fattr->cf_dtype = DT_REG;
 	}
 
+	/* non-unix readdir doesn't provide nlink */
+	fattr->cf_flags |= CIFS_FATTR_UNKNOWN_NLINK;
+
 	if (fattr->cf_cifsattrs & ATTR_READONLY)
 		fattr->cf_mode &= ~S_IWUGO;
 

fs/cifs/sess.c

···
 #include <linux/slab.h>
 #include "cifs_spnego.h"
 
-/*
- * Checks if this is the first smb session to be reconnected after
- * the socket has been reestablished (so we know whether to use vc 0).
- * Called while holding the cifs_tcp_ses_lock, so do not block
- */
-static bool is_first_ses_reconnect(struct cifs_ses *ses)
-{
-	struct list_head *tmp;
-	struct cifs_ses *tmp_ses;
-
-	list_for_each(tmp, &ses->server->smb_ses_list) {
-		tmp_ses = list_entry(tmp, struct cifs_ses,
-				     smb_ses_list);
-		if (tmp_ses->need_reconnect == false)
-			return false;
-	}
-	/* could not find a session that was already connected,
-	   this must be the first one we are reconnecting */
-	return true;
-}
-
-/*
- *	vc number 0 is treated specially by some servers, and should be the
- *      first one we request.  After that we can use vcnumbers up to maxvcs,
- *	one for each smb session (some Windows versions set maxvcs incorrectly
- *	so maxvc=1 can be ignored).  If we have too many vcs, we can reuse
- *	any vc but zero (some servers reset the connection on vcnum zero)
- *
- */
-static __le16 get_next_vcnum(struct cifs_ses *ses)
-{
-	__u16 vcnum = 0;
-	struct list_head *tmp;
-	struct cifs_ses *tmp_ses;
-	__u16 max_vcs = ses->server->max_vcs;
-	__u16 i;
-	int free_vc_found = 0;
-
-	/* Quoting the MS-SMB specification: "Windows-based SMB servers set this
-	field to one but do not enforce this limit, which allows an SMB client
-	to establish more virtual circuits than allowed by this value ... but
-	other server implementations can enforce this limit." */
-	if (max_vcs < 2)
-		max_vcs = 0xFFFF;
-
-	spin_lock(&cifs_tcp_ses_lock);
-	if ((ses->need_reconnect) && is_first_ses_reconnect(ses))
-			goto get_vc_num_exit;  /* vcnum will be zero */
-	for (i = ses->server->srv_count - 1; i < max_vcs; i++) {
-		if (i == 0) /* this is the only connection, use vc 0 */
-			break;
-
-		free_vc_found = 1;
-
-		list_for_each(tmp, &ses->server->smb_ses_list) {
-			tmp_ses = list_entry(tmp, struct cifs_ses,
-					     smb_ses_list);
-			if (tmp_ses->vcnum == i) {
-				free_vc_found = 0;
-				break; /* found duplicate, try next vcnum */
-			}
-		}
-		if (free_vc_found)
-			break; /* we found a vcnumber that will work - use it */
-	}
-
-	if (i == 0)
-		vcnum = 0; /* for most common case, ie if one smb session, use
-			      vc zero.  Also for case when no free vcnum, zero
-			      is safest to send (some clients only send zero) */
-	else if (free_vc_found == 0)
-		vcnum = 1;  /* we can not reuse vc=0 safely, since some servers
-				reset all uids on that, but 1 is ok. */
-	else
-		vcnum = i;
-	ses->vcnum = vcnum;
-get_vc_num_exit:
-	spin_unlock(&cifs_tcp_ses_lock);
-
-	return cpu_to_le16(vcnum);
-}
-
 static __u32 cifs_ssetup_hdr(struct cifs_ses *ses, SESSION_SETUP_ANDX *pSMB)
 {
 	__u32 capabilities = 0;
···
 					CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4,
 					USHRT_MAX));
 	pSMB->req.MaxMpxCount = cpu_to_le16(ses->server->maxReq);
-	pSMB->req.VcNumber = get_next_vcnum(ses);
+	pSMB->req.VcNumber = __constant_cpu_to_le16(1);
 
 	/* Now no need to set SMBFLG_CASELESS or obsolete CANONICAL PATH */