We analyze a client FS's capabilities -- i.e. which hooks it provides or

can be emulated -- and pass this info to the kernel add-on. Thus we can
avoid passing requests to the userland that can't be serviced anyway.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@20331 a95241bf-73f2-0310-859d-f6bbb57e9c96

headers/private/userlandfs/private/FSCapabilities.h

@@ -0,0 +1,191 @@
+// FSCapabilities.h
+
+#ifndef USERLAND_FS_FS_CAPABILITIES_H
+#define USERLAND_FS_FS_CAPABILITIES_H
+
+#include <string.h>
+#include <stdio.h>
+
+#include "Debug.h"
+
+enum client_fs_type {
+	CLIENT_FS_BEOS_KERNEL = 0,
+	CLIENT_FS_HAIKU_KERNEL,
+};
+
+enum {
+	// FS operations
+	FS_CAPABILITY_MOUNT	= 0,
+	FS_CAPABILITY_UNMOUNT,
+
+	FS_CAPABILITY_READ_FS_INFO,
+	FS_CAPABILITY_WRITE_FS_INFO,
+	FS_CAPABILITY_SYNC,
+
+	// vnode operations
+	FS_CAPABILITY_LOOKUP,
+	FS_CAPABILITY_GET_VNODE_NAME,
+
+	FS_CAPABILITY_GET_VNODE,
+	FS_CAPABILITY_PUT_VNODE,
+	FS_CAPABILITY_REMOVE_VNODE,
+
+	// VM file access
+	FS_CAPABILITY_CAN_PAGE,
+	FS_CAPABILITY_READ_PAGES,
+	FS_CAPABILITY_WRITE_PAGES,
+
+	// cache file access
+	FS_CAPABILITY_GET_FILE_MAP,
+
+	// common operations
+	FS_CAPABILITY_IOCTL,
+	FS_CAPABILITY_SET_FLAGS,
+	FS_CAPABILITY_SELECT,
+	FS_CAPABILITY_DESELECT,
+	FS_CAPABILITY_FSYNC,
+
+	FS_CAPABILITY_READ_SYMLINK,
+	FS_CAPABILITY_CREATE_SYMLINK,
+
+	FS_CAPABILITY_LINK,
+	FS_CAPABILITY_UNLINK,
+	FS_CAPABILITY_RENAME,
+
+	FS_CAPABILITY_ACCESS,
+	FS_CAPABILITY_READ_STAT,
+	FS_CAPABILITY_WRITE_STAT,
+
+	// file operations
+	FS_CAPABILITY_CREATE,
+	FS_CAPABILITY_OPEN,
+	FS_CAPABILITY_CLOSE,
+	FS_CAPABILITY_FREE_COOKIE,
+	FS_CAPABILITY_READ,
+	FS_CAPABILITY_WRITE,
+
+	// directory operations
+	FS_CAPABILITY_CREATE_DIR,
+	FS_CAPABILITY_REMOVE_DIR,
+	FS_CAPABILITY_OPEN_DIR,
+	FS_CAPABILITY_CLOSE_DIR,
+	FS_CAPABILITY_FREE_DIR_COOKIE,
+	FS_CAPABILITY_READ_DIR,
+	FS_CAPABILITY_REWIND_DIR,
+
+	// attribute directory operations
+	FS_CAPABILITY_OPEN_ATTR_DIR,
+	FS_CAPABILITY_CLOSE_ATTR_DIR,
+	FS_CAPABILITY_FREE_ATTR_DIR_COOKIE,
+	FS_CAPABILITY_READ_ATTR_DIR,
+	FS_CAPABILITY_REWIND_ATTR_DIR,
+
+	// attribute operations
+	FS_CAPABILITY_CREATE_ATTR,
+	FS_CAPABILITY_OPEN_ATTR,
+	FS_CAPABILITY_CLOSE_ATTR,
+	FS_CAPABILITY_FREE_ATTR_COOKIE,
+	FS_CAPABILITY_READ_ATTR,
+	FS_CAPABILITY_WRITE_ATTR,
+
+	FS_CAPABILITY_READ_ATTR_STAT,
+	FS_CAPABILITY_WRITE_ATTR_STAT,
+	FS_CAPABILITY_RENAME_ATTR,
+	FS_CAPABILITY_REMOVE_ATTR,
+
+	// index directory & index operations
+	FS_CAPABILITY_OPEN_INDEX_DIR,
+	FS_CAPABILITY_CLOSE_INDEX_DIR,
+	FS_CAPABILITY_FREE_INDEX_DIR_COOKIE,
+	FS_CAPABILITY_READ_INDEX_DIR,
+	FS_CAPABILITY_REWIND_INDEX_DIR,
+
+	FS_CAPABILITY_CREATE_INDEX,
+	FS_CAPABILITY_REMOVE_INDEX,
+	FS_CAPABILITY_READ_INDEX_STAT,
+
+	// query operations
+	FS_CAPABILITY_OPEN_QUERY,
+	FS_CAPABILITY_CLOSE_QUERY,
+	FS_CAPABILITY_FREE_QUERY_COOKIE,
+	FS_CAPABILITY_READ_QUERY,
+	FS_CAPABILITY_REWIND_QUERY,
+
+	FS_CAPABILITY_COUNT,
+};
+
+
+namespace UserlandFSUtil {
+
+struct FSCapabilities {
+			client_fs_type		clientFSType;
+			uint8				capabilities[(FS_CAPABILITY_COUNT + 7) / 8];
+
+	inline	void				ClearAll();
+
+	inline	void				Set(uint32 capability, bool set = true);
+	inline	void				Clear(uint32 capability);
+	inline	bool				Get(uint32 capability) const;
+
+	inline	void				Dump() const;
+};
+
+// ClearAll
+inline void
+FSCapabilities::ClearAll()
+{
+	memset(capabilities, 0, sizeof(capabilities));
+}
+
+// Set
+inline void
+FSCapabilities::Set(uint32 capability, bool set)
+{
+	if (capability >= FS_CAPABILITY_COUNT)
+		return;
+
+	uint8 flag = uint8(1 << (capability % 8));
+	if (set)
+		capabilities[capability / 8] |= flag;
+	else
+		capabilities[capability / 8] &= ~flag;
+}
+
+// Clear
+inline void
+FSCapabilities::Clear(uint32 capability)
+{
+	Set(capability, false);
+}
+
+// Get
+inline bool
+FSCapabilities::Get(uint32 capability) const
+{
+	if (capability >= FS_CAPABILITY_COUNT)
+		return false;
+
+	uint8 flag = uint8(1 << (capability % 8));
+	return (capabilities[capability / 8] & flag);
+}
+
+// Dump
+inline void
+FSCapabilities::Dump() const
+{
+	D(
+		char buffer[128];
+		int byteCount = sizeof(capabilities);
+		for (int i = 0; i < byteCount; i++)
+			sprintf(buffer + 2 * i, "%02x", (int)capabilities[i]);
+
+		PRINT(("FSCapabilities[%d, %s]\n", clientFSType, buffer));
+	)
+}
+
+
+}	// namespace UserlandFSUtil
+
+using UserlandFSUtil::FSCapabilities;
+
+#endif	// USERLAND_FS_FS_CAPABILITIES_H

headers/private/userlandfs/private/Requests.h

@@ -9,6 +9,7 @@
 #include <fs_interface.h>
 
 #include "Compatibility.h"
+#include "FSCapabilities.h"
 #include "Request.h"
 
 
@@ -304,8 +305,9 @@ public:
 	FSConnectReply() : ReplyRequest(FS_CONNECT_REPLY) {}
 	status_t GetAddressInfos(AddressInfo* infos, int32* count);
 
-	Address		portInfos;
+	Address			portInfos;
-	int32		portInfoCount;
+	int32			portInfoCount;
+	FSCapabilities	capabilities;
 };
 
 

src/add-ons/kernel/file_systems/userlandfs/kernel_add_on/FileSystem.cpp

@@ -64,9 +64,11 @@ FileSystem::~FileSystem()
 
 // Init
 status_t
-FileSystem::Init(const char* name, Port::Info* infos, int32 count)
+FileSystem::Init(const char* name, Port::Info* infos, int32 count,
+	const FSCapabilities& capabilities)
 {
-	PRINT(("FileSystem::Init(\"%s\", %p, %ld)\n", name, infos, infoCount));
+	PRINT(("FileSystem::Init(\"%s\", %p, %ld)\n", name, infos, count));
+	capabilities.Dump();
 
 	// check parameters
 	if (!name || !infos || count < 2)
@@ -76,6 +78,8 @@ FileSystem::Init(const char* name, Port::Info* infos, int32 count)
 	if (!fName.SetTo(name))
 		return B_NO_MEMORY;
 
+	fCapabilities = capabilities;
+
 	// create the select sync entry map
 	fSelectSyncs = new(nothrow) SelectSyncMap;
 	if (!fSelectSyncs)
@@ -159,6 +163,13 @@ FileSystem::GetName() const
 	return fName.GetString();
 }
 
+// GetCapabilities
+const FSCapabilities&
+FileSystem::GetCapabilities() const
+{
+	return fCapabilities;
+}
+
 // GetPortPool
 RequestPortPool*
 FileSystem::GetPortPool()

src/add-ons/kernel/file_systems/userlandfs/kernel_add_on/FileSystem.h

@@ -5,6 +5,7 @@
 
 #include <fs_interface.h>
 
+#include "FSCapabilities.h"
 #include "LazyInitializable.h"
 #include "Locker.h"
 #include "Referencable.h"
@@ -24,10 +25,14 @@ public:
 								~FileSystem();
 
 			status_t			Init(const char* name, Port::Info* infos,
-									int32 infoCount);
+									int32 infoCount,
+									const FSCapabilities& capabilities);
 
 			const char*			GetName() const;
 
+			const FSCapabilities& GetCapabilities() const;
+	inline	bool				HasCapability(uint32 capability) const;
+
 			RequestPortPool*	GetPortPool();
 
 			status_t			Mount(mount_id id, const char* device,
@@ -59,6 +64,7 @@ private:
 			Vector<Volume*>		fVolumes;
 			Locker				fVolumeLock;
 			String				fName;
+			FSCapabilities		fCapabilities;
 			RequestPort*		fNotificationPort;
 			thread_id			fNotificationThread;
 			RequestPortPool		fPortPool;
@@ -69,4 +75,12 @@ private:
 	volatile bool				fTerminating;
 };
 
+
+// HasCapability
+inline bool
+FileSystem::HasCapability(uint32 capability) const
+{
+	return fCapabilities.Get(capability);
+}
+
 #endif	// USERLAND_FS_FILE_SYSTEM_H

src/add-ons/kernel/file_systems/userlandfs/kernel_add_on/FileSystemInitializer.cpp

@@ -68,7 +68,7 @@ FileSystemInitializer::FirstTimeInit()
 	if (!fFileSystem)
 		return B_NO_MEMORY;
 
-	error = fFileSystem->Init(fName, infos, count);
+	error = fFileSystem->Init(fName, infos, count, reply->capabilities);
 	if (error != B_OK)
 		return B_ERROR;
 

src/add-ons/kernel/file_systems/userlandfs/kernel_add_on/Volume.cpp

@@ -280,6 +280,10 @@ Volume::Unmount()
 status_t
 Volume::Sync()
 {
+	// check capability
+	if (!fFileSystem->HasCapability(FS_CAPABILITY_SYNC))
+		return B_BAD_VALUE;
+
 	// get a free port
 	RequestPort* port = fFileSystem->GetPortPool()->AcquirePort();
 	if (!port)
@@ -337,6 +341,10 @@ Volume::ReadFSInfo(fs_info* info)
 status_t
 Volume::WriteFSInfo(const struct fs_info *info, uint32 mask)
 {
+	// check capability
+	if (!fFileSystem->HasCapability(FS_CAPABILITY_WRITE_FS_INFO))
+		return B_BAD_VALUE;
+
 	// get a free port
 	RequestPort* port = fFileSystem->GetPortPool()->AcquirePort();
 	if (!port)
@@ -574,6 +582,10 @@ Volume::IOCtl(fs_vnode node, fs_cookie cookie, uint32 command, void *buffer,
 		}
 	}
 
+	// check capability
+	if (!fFileSystem->HasCapability(FS_CAPABILITY_IOCTL))
+		return B_BAD_VALUE;
+
 	// get a free port
 	RequestPort* port = fFileSystem->GetPortPool()->AcquirePort();
 	if (!port)
@@ -630,6 +642,10 @@ Volume::IOCtl(fs_vnode node, fs_cookie cookie, uint32 command, void *buffer,
 status_t
 Volume::SetFlags(fs_vnode node, fs_cookie cookie, int flags)
 {
+	// check capability
+	if (!fFileSystem->HasCapability(FS_CAPABILITY_SET_FLAGS))
+		return B_BAD_VALUE;
+
 	// get a free port
 	RequestPort* port = fFileSystem->GetPortPool()->AcquirePort();
 	if (!port)
@@ -667,6 +683,12 @@ status_t
 Volume::Select(fs_vnode node, fs_cookie cookie, uint8 event, uint32 ref,
 	selectsync* sync)
 {
+	// check capability
+	if (!fFileSystem->HasCapability(FS_CAPABILITY_SELECT)) {
+		notify_select_event(sync, ref, event);
+		return B_OK;
+	}
+
 	// get a free port
 	RequestPort* port = fFileSystem->GetPortPool()->AcquirePort();
 	if (!port)
@@ -714,6 +736,10 @@ Volume::Select(fs_vnode node, fs_cookie cookie, uint8 event, uint32 ref,
 status_t
 Volume::Deselect(fs_vnode node, fs_cookie cookie, uint8 event, selectsync* sync)
 {
+	// check capability
+	if (!fFileSystem->HasCapability(FS_CAPABILITY_DESELECT))
+		return B_OK;
+
 	struct SyncRemover {
 		SyncRemover(FileSystem* fs, selectsync* sync)
 			: fs(fs), sync(sync) {}
@@ -760,6 +786,10 @@ Volume::Deselect(fs_vnode node, fs_cookie cookie, uint8 event, selectsync* sync)
 status_t
 Volume::FSync(fs_vnode node)
 {
+	// check capability
+	if (!fFileSystem->HasCapability(FS_CAPABILITY_FSYNC))
+		return B_BAD_VALUE;
+
 	// get a free port
 	RequestPort* port = fFileSystem->GetPortPool()->AcquirePort();
 	if (!port)
@@ -796,6 +826,11 @@ Volume::ReadSymlink(fs_vnode node, char* buffer, size_t bufferSize,
 	size_t* bytesRead)
 {
 	*bytesRead = 0;
+
+	// check capability
+	if (!fFileSystem->HasCapability(FS_CAPABILITY_READ_SYMLINK))
+		return B_BAD_VALUE;
+
 	// get a free port
 	RequestPort* port = fFileSystem->GetPortPool()->AcquirePort();
 	if (!port)
@@ -841,6 +876,10 @@ status_t
 Volume::CreateSymlink(fs_vnode dir, const char* name, const char* target,
 	int mode)
 {
+	// check capability
+	if (!fFileSystem->HasCapability(FS_CAPABILITY_CREATE_SYMLINK))
+		return B_BAD_VALUE;
+
 	// get a free port
 	RequestPort* port = fFileSystem->GetPortPool()->AcquirePort();
 	if (!port)
@@ -881,6 +920,10 @@ Volume::CreateSymlink(fs_vnode dir, const char* name, const char* target,
 status_t
 Volume::Link(fs_vnode dir, const char* name, fs_vnode node)
 {
+	// check capability
+	if (!fFileSystem->HasCapability(FS_CAPABILITY_LINK))
+		return B_BAD_VALUE;
+
 	// get a free port
 	RequestPort* port = fFileSystem->GetPortPool()->AcquirePort();
 	if (!port)
@@ -919,6 +962,10 @@ Volume::Link(fs_vnode dir, const char* name, fs_vnode node)
 status_t
 Volume::Unlink(fs_vnode dir, const char* name)
 {
+	// check capability
+	if (!fFileSystem->HasCapability(FS_CAPABILITY_UNLINK))
+		return B_BAD_VALUE;
+
 	// get a free port
 	RequestPort* port = fFileSystem->GetPortPool()->AcquirePort();
 	if (!port)
@@ -957,6 +1004,10 @@ status_t
 Volume::Rename(fs_vnode oldDir, const char* oldName, fs_vnode newDir,
 	const char* newName)
 {
+	// check capability
+	if (!fFileSystem->HasCapability(FS_CAPABILITY_RENAME))
+		return B_BAD_VALUE;
+
 	// get a free port
 	RequestPort* port = fFileSystem->GetPortPool()->AcquirePort();
 	if (!port)
@@ -997,6 +1048,10 @@ Volume::Rename(fs_vnode oldDir, const char* oldName, fs_vnode newDir,
 status_t
 Volume::Access(fs_vnode node, int mode)
 {
+	// check capability
+	if (!fFileSystem->HasCapability(FS_CAPABILITY_ACCESS))
+		return B_OK;
+
 	// get a free port
 	RequestPort* port = fFileSystem->GetPortPool()->AcquirePort();
 	if (!port)
@@ -1062,6 +1117,10 @@ Volume::ReadStat(fs_vnode node, struct stat* st)
 status_t
 Volume::WriteStat(fs_vnode node, const struct stat* st, uint32 mask)
 {
+	// check capability
+	if (!fFileSystem->HasCapability(FS_CAPABILITY_WRITE_STAT))
+		return B_BAD_VALUE;
+
 	// get a free port
 	RequestPort* port = fFileSystem->GetPortPool()->AcquirePort();
 	if (!port)
@@ -1102,6 +1161,10 @@ status_t
 Volume::Create(fs_vnode dir, const char* name, int openMode, int mode,
 	void** cookie, vnode_id* vnid)
 {
+	// check capability
+	if (!fFileSystem->HasCapability(FS_CAPABILITY_CREATE))
+		return B_BAD_VALUE;
+
 	// get a free port
 	RequestPort* port = fFileSystem->GetPortPool()->AcquirePort();
 	if (!port)
@@ -1148,6 +1211,10 @@ Volume::Create(fs_vnode dir, const char* name, int openMode, int mode,
 status_t
 Volume::Open(fs_vnode node, int openMode, fs_cookie* cookie)
 {
+	// check capability
+	if (!fFileSystem->HasCapability(FS_CAPABILITY_OPEN))
+		return B_BAD_VALUE;
+
 	// get a free port
 	RequestPort* port = fFileSystem->GetPortPool()->AcquirePort();
 	if (!port)
@@ -1223,6 +1290,10 @@ Volume::Read(fs_vnode node, fs_cookie cookie, off_t pos, void* buffer,
 {
 	*bytesRead = 0;
 
+	// check capability
+	if (!fFileSystem->HasCapability(FS_CAPABILITY_READ))
+		return B_BAD_VALUE;
+
 	// get a free port
 	RequestPort* port = fFileSystem->GetPortPool()->AcquirePort();
 	if (!port)
@@ -1272,6 +1343,10 @@ Volume::Write(fs_vnode node, fs_cookie cookie, off_t pos, const void* buffer,
 {
 	*bytesWritten = 0;
 
+	// check capability
+	if (!fFileSystem->HasCapability(FS_CAPABILITY_WRITE))
+		return B_BAD_VALUE;
+
 	// get a free port
 	RequestPort* port = fFileSystem->GetPortPool()->AcquirePort();
 	if (!port)
@@ -1315,6 +1390,10 @@ Volume::Write(fs_vnode node, fs_cookie cookie, off_t pos, const void* buffer,
 status_t
 Volume::CreateDir(fs_vnode dir, const char* name, int mode, vnode_id *newDir)
 {
+	// check capability
+	if (!fFileSystem->HasCapability(FS_CAPABILITY_CREATE_DIR))
+		return B_BAD_VALUE;
+
 	// get a free port
 	RequestPort* port = fFileSystem->GetPortPool()->AcquirePort();
 	if (!port)
@@ -1354,6 +1433,10 @@ Volume::CreateDir(fs_vnode dir, const char* name, int mode, vnode_id *newDir)
 status_t
 Volume::RemoveDir(fs_vnode dir, const char* name)
 {
+	// check capability
+	if (!fFileSystem->HasCapability(FS_CAPABILITY_REMOVE_DIR))
+		return B_BAD_VALUE;
+
 	// get a free port
 	RequestPort* port = fFileSystem->GetPortPool()->AcquirePort();
 	if (!port)
@@ -1391,6 +1474,10 @@ Volume::RemoveDir(fs_vnode dir, const char* name)
 status_t
 Volume::OpenDir(fs_vnode node, fs_cookie* cookie)
 {
+	// check capability
+	if (!fFileSystem->HasCapability(FS_CAPABILITY_OPEN_DIR))
+		return B_BAD_VALUE;
+
 	// get a free port
 	RequestPort* port = fFileSystem->GetPortPool()->AcquirePort();
 	if (!port)
@@ -1466,6 +1553,10 @@ Volume::ReadDir(fs_vnode node, fs_vnode cookie, void* buffer, size_t bufferSize,
 {
 	*countRead = 0;
 
+	// check capability
+	if (!fFileSystem->HasCapability(FS_CAPABILITY_READ_DIR))
+		return B_BAD_VALUE;
+
 	// get a free port
 	RequestPort* port = fFileSystem->GetPortPool()->AcquirePort();
 	if (!port)
@@ -1521,6 +1612,10 @@ reply->buffer.GetSize()));
 status_t
 Volume::RewindDir(fs_vnode node, fs_vnode cookie)
 {
+	// check capability
+	if (!fFileSystem->HasCapability(FS_CAPABILITY_REWIND_DIR))
+		return B_BAD_VALUE;
+
 	// get a free port
 	RequestPort* port = fFileSystem->GetPortPool()->AcquirePort();
 	if (!port)
@@ -1560,6 +1655,10 @@ Volume::RewindDir(fs_vnode node, fs_vnode cookie)
 status_t
 Volume::OpenAttrDir(fs_vnode node, fs_cookie *cookie)
 {
+	// check capability
+	if (!fFileSystem->HasCapability(FS_CAPABILITY_OPEN_ATTR_DIR))
+		return B_BAD_VALUE;
+
 	// get a free port
 	RequestPort* port = fFileSystem->GetPortPool()->AcquirePort();
 	if (!port)
@@ -1635,6 +1734,10 @@ status_t
 Volume::ReadAttrDir(fs_vnode node, fs_cookie cookie, void* buffer,
 	size_t bufferSize, uint32 count, uint32* countRead)
 {
+	// check capability
+	if (!fFileSystem->HasCapability(FS_CAPABILITY_READ_ATTR_DIR))
+		return B_BAD_VALUE;
+
 	*countRead = 0;
 	// get a free port
 	RequestPort* port = fFileSystem->GetPortPool()->AcquirePort();
@@ -1689,6 +1792,10 @@ Volume::ReadAttrDir(fs_vnode node, fs_cookie cookie, void* buffer,
 status_t
 Volume::RewindAttrDir(fs_vnode node, fs_cookie cookie)
 {
+	// check capability
+	if (!fFileSystem->HasCapability(FS_CAPABILITY_REWIND_ATTR_DIR))
+		return B_BAD_VALUE;
+
 	// get a free port
 	RequestPort* port = fFileSystem->GetPortPool()->AcquirePort();
 	if (!port)
@@ -1728,6 +1835,10 @@ status_t
 Volume::CreateAttr(fs_vnode node, const char* name, uint32 type, int openMode,
 	fs_cookie* cookie)
 {
+	// check capability
+	if (!fFileSystem->HasCapability(FS_CAPABILITY_CREATE_ATTR))
+		return B_BAD_VALUE;
+
 	// get a free port
 	RequestPort* port = fFileSystem->GetPortPool()->AcquirePort();
 	if (!port)
@@ -1771,6 +1882,10 @@ status_t
 Volume::OpenAttr(fs_vnode node, const char* name, int openMode,
 	fs_cookie* cookie)
 {
+	// check capability
+	if (!fFileSystem->HasCapability(FS_CAPABILITY_OPEN_ATTR))
+		return B_BAD_VALUE;
+
 	// get a free port
 	RequestPort* port = fFileSystem->GetPortPool()->AcquirePort();
 	if (!port)
@@ -1851,6 +1966,10 @@ Volume::ReadAttr(fs_vnode node, fs_cookie cookie, off_t pos,
 {
 	*bytesRead = 0;
 
+	// check capability
+	if (!fFileSystem->HasCapability(FS_CAPABILITY_READ_ATTR))
+		return B_BAD_VALUE;
+
 	// get a free port
 	RequestPort* port = fFileSystem->GetPortPool()->AcquirePort();
 	if (!port)
@@ -1900,6 +2019,10 @@ Volume::WriteAttr(fs_vnode node, fs_cookie cookie, off_t pos,
 {
 	*bytesWritten = 0;
 
+	// check capability
+	if (!fFileSystem->HasCapability(FS_CAPABILITY_WRITE_ATTR))
+		return B_BAD_VALUE;
+
 	// get a free port
 	RequestPort* port = fFileSystem->GetPortPool()->AcquirePort();
 	if (!port)
@@ -1940,6 +2063,10 @@ Volume::WriteAttr(fs_vnode node, fs_cookie cookie, off_t pos,
 status_t
 Volume::ReadAttrStat(fs_vnode node, fs_cookie cookie, struct stat *st)
 {
+	// check capability
+	if (!fFileSystem->HasCapability(FS_CAPABILITY_READ_ATTR_STAT))
+		return B_BAD_VALUE;
+
 	// get a free port
 	RequestPort* port = fFileSystem->GetPortPool()->AcquirePort();
 	if (!port)
@@ -1977,6 +2104,10 @@ status_t
 Volume::RenameAttr(fs_vnode oldNode, const char* oldName, fs_vnode newNode,
 	const char* newName)
 {
+	// check capability
+	if (!fFileSystem->HasCapability(FS_CAPABILITY_RENAME_ATTR))
+		return B_BAD_VALUE;
+
 	// get a free port
 	RequestPort* port = fFileSystem->GetPortPool()->AcquirePort();
 	if (!port)
@@ -2017,6 +2148,10 @@ Volume::RenameAttr(fs_vnode oldNode, const char* oldName, fs_vnode newNode,
 status_t
 Volume::RemoveAttr(fs_vnode node, const char* name)
 {
+	// check capability
+	if (!fFileSystem->HasCapability(FS_CAPABILITY_REMOVE_ATTR))
+		return B_BAD_VALUE;
+
 	// get a free port
 	RequestPort* port = fFileSystem->GetPortPool()->AcquirePort();
 	if (!port)
@@ -2058,6 +2193,10 @@ Volume::RemoveAttr(fs_vnode node, const char* name)
 status_t
 Volume::OpenIndexDir(fs_cookie *cookie)
 {
+	// check capability
+	if (!fFileSystem->HasCapability(FS_CAPABILITY_OPEN_INDEX_DIR))
+		return B_BAD_VALUE;
+
 	// get a free port
 	RequestPort* port = fFileSystem->GetPortPool()->AcquirePort();
 	if (!port)
@@ -2134,6 +2273,10 @@ Volume::ReadIndexDir(fs_cookie cookie, void* buffer, size_t bufferSize,
 {
 	*countRead = 0;
 
+	// check capability
+	if (!fFileSystem->HasCapability(FS_CAPABILITY_READ_INDEX_DIR))
+		return B_BAD_VALUE;
+
 	// get a free port
 	RequestPort* port = fFileSystem->GetPortPool()->AcquirePort();
 	if (!port)
@@ -2186,6 +2329,10 @@ Volume::ReadIndexDir(fs_cookie cookie, void* buffer, size_t bufferSize,
 status_t
 Volume::RewindIndexDir(fs_cookie cookie)
 {
+	// check capability
+	if (!fFileSystem->HasCapability(FS_CAPABILITY_REWIND_INDEX_DIR))
+		return B_BAD_VALUE;
+
 	// get a free port
 	RequestPort* port = fFileSystem->GetPortPool()->AcquirePort();
 	if (!port)
@@ -2220,6 +2367,10 @@ Volume::RewindIndexDir(fs_cookie cookie)
 status_t
 Volume::CreateIndex(const char* name, uint32 type, uint32 flags)
 {
+	// check capability
+	if (!fFileSystem->HasCapability(FS_CAPABILITY_CREATE_INDEX))
+		return B_BAD_VALUE;
+
 	// get a free port
 	RequestPort* port = fFileSystem->GetPortPool()->AcquirePort();
 	if (!port)
@@ -2258,6 +2409,10 @@ Volume::CreateIndex(const char* name, uint32 type, uint32 flags)
 status_t
 Volume::RemoveIndex(const char* name)
 {
+	// check capability
+	if (!fFileSystem->HasCapability(FS_CAPABILITY_REMOVE_INDEX))
+		return B_BAD_VALUE;
+
 	// get a free port
 	RequestPort* port = fFileSystem->GetPortPool()->AcquirePort();
 	if (!port)
@@ -2294,6 +2449,10 @@ Volume::RemoveIndex(const char* name)
 status_t
 Volume::ReadIndexStat(const char* name, struct stat *st)
 {
+	// check capability
+	if (!fFileSystem->HasCapability(FS_CAPABILITY_READ_INDEX_STAT))
+		return B_BAD_VALUE;
+
 	// get a free port
 	RequestPort* port = fFileSystem->GetPortPool()->AcquirePort();
 	if (!port)
@@ -2336,6 +2495,10 @@ status_t
 Volume::OpenQuery(const char* queryString, uint32 flags, port_id targetPort,
 	uint32 token, fs_cookie *cookie)
 {
+	// check capability
+	if (!fFileSystem->HasCapability(FS_CAPABILITY_OPEN_QUERY))
+		return B_BAD_VALUE;
+
 	// get a free port
 	RequestPort* port = fFileSystem->GetPortPool()->AcquirePort();
 	if (!port)
@@ -2417,6 +2580,10 @@ Volume::ReadQuery(fs_cookie cookie, void* buffer, size_t bufferSize,
 {
 	*countRead = 0;
 
+	// check capability
+	if (!fFileSystem->HasCapability(FS_CAPABILITY_READ_QUERY))
+		return B_BAD_VALUE;
+
 	// get a free port
 	RequestPort* port = fFileSystem->GetPortPool()->AcquirePort();
 	if (!port)
@@ -2560,6 +2727,10 @@ Volume::_Unmount()
 status_t
 Volume::_ReadFSInfo(fs_info* info)
 {
+	// check capability
+	if (!fFileSystem->HasCapability(FS_CAPABILITY_READ_FS_INFO))
+		return B_BAD_VALUE;
+
 	// get a free port
 	RequestPort* port = fFileSystem->GetPortPool()->AcquirePort();
 	if (!port)
@@ -2669,6 +2840,10 @@ Volume::_WriteVNode(fs_vnode node, bool reenter)
 status_t
 Volume::_ReadStat(fs_vnode node, struct stat* st)
 {
+	// check capability
+	if (!fFileSystem->HasCapability(FS_CAPABILITY_READ_STAT))
+		return B_BAD_VALUE;
+
 	// get a free port
 	RequestPort* port = fFileSystem->GetPortPool()->AcquirePort();
 	if (!port)
@@ -2704,6 +2879,10 @@ Volume::_ReadStat(fs_vnode node, struct stat* st)
 status_t
 Volume::_Close(fs_vnode node, fs_cookie cookie)
 {
+	// check capability
+	if (!fFileSystem->HasCapability(FS_CAPABILITY_CLOSE))
+		return B_OK;
+
 	// get a free port
 	RequestPort* port = fFileSystem->GetPortPool()->AcquirePort();
 	if (!port)
@@ -2739,6 +2918,10 @@ Volume::_Close(fs_vnode node, fs_cookie cookie)
 status_t
 Volume::_FreeCookie(fs_vnode node, fs_cookie cookie)
 {
+	// check capability
+	if (!fFileSystem->HasCapability(FS_CAPABILITY_FREE_COOKIE))
+		return B_OK;
+
 	// get a free port
 	RequestPort* port = fFileSystem->GetPortPool()->AcquirePort();
 	if (!port)
@@ -2774,6 +2957,10 @@ Volume::_FreeCookie(fs_vnode node, fs_cookie cookie)
 status_t
 Volume::_CloseDir(fs_vnode node, fs_vnode cookie)
 {
+	// check capability
+	if (!fFileSystem->HasCapability(FS_CAPABILITY_CLOSE_DIR))
+		return B_OK;
+
 	// get a free port
 	RequestPort* port = fFileSystem->GetPortPool()->AcquirePort();
 	if (!port)
@@ -2809,6 +2996,10 @@ Volume::_CloseDir(fs_vnode node, fs_vnode cookie)
 status_t
 Volume::_FreeDirCookie(fs_vnode node, fs_vnode cookie)
 {
+	// check capability
+	if (!fFileSystem->HasCapability(FS_CAPABILITY_FREE_DIR_COOKIE))
+		return B_OK;
+
 	// get a free port
 	RequestPort* port = fFileSystem->GetPortPool()->AcquirePort();
 	if (!port)
@@ -2844,6 +3035,10 @@ Volume::_FreeDirCookie(fs_vnode node, fs_vnode cookie)
 status_t
 Volume::_CloseAttrDir(fs_vnode node, fs_cookie cookie)
 {
+	// check capability
+	if (!fFileSystem->HasCapability(FS_CAPABILITY_CLOSE_ATTR_DIR))
+		return B_OK;
+
 	// get a free port
 	RequestPort* port = fFileSystem->GetPortPool()->AcquirePort();
 	if (!port)
@@ -2879,6 +3074,10 @@ Volume::_CloseAttrDir(fs_vnode node, fs_cookie cookie)
 status_t
 Volume::_FreeAttrDirCookie(fs_vnode node, fs_cookie cookie)
 {
+	// check capability
+	if (!fFileSystem->HasCapability(FS_CAPABILITY_FREE_ATTR_DIR_COOKIE))
+		return B_OK;
+
 	// get a free port
 	RequestPort* port = fFileSystem->GetPortPool()->AcquirePort();
 	if (!port)
@@ -2914,6 +3113,10 @@ Volume::_FreeAttrDirCookie(fs_vnode node, fs_cookie cookie)
 status_t
 Volume::_CloseAttr(fs_vnode node, fs_cookie cookie)
 {
+	// check capability
+	if (!fFileSystem->HasCapability(FS_CAPABILITY_CLOSE_ATTR))
+		return B_OK;
+
 	// get a free port
 	RequestPort* port = fFileSystem->GetPortPool()->AcquirePort();
 	if (!port)
@@ -2949,6 +3152,10 @@ Volume::_CloseAttr(fs_vnode node, fs_cookie cookie)
 status_t
 Volume::_FreeAttrCookie(fs_vnode node, fs_cookie cookie)
 {
+	// check capability
+	if (!fFileSystem->HasCapability(FS_CAPABILITY_FREE_ATTR_COOKIE))
+		return B_OK;
+
 	// get a free port
 	RequestPort* port = fFileSystem->GetPortPool()->AcquirePort();
 	if (!port)
@@ -2984,6 +3191,10 @@ Volume::_FreeAttrCookie(fs_vnode node, fs_cookie cookie)
 status_t
 Volume::_CloseIndexDir(fs_cookie cookie)
 {
+	// check capability
+	if (!fFileSystem->HasCapability(FS_CAPABILITY_CLOSE_INDEX_DIR))
+		return B_OK;
+
 	// get a free port
 	RequestPort* port = fFileSystem->GetPortPool()->AcquirePort();
 	if (!port)
@@ -3018,6 +3229,10 @@ Volume::_CloseIndexDir(fs_cookie cookie)
 status_t
 Volume::_FreeIndexDirCookie(fs_cookie cookie)
 {
+	// check capability
+	if (!fFileSystem->HasCapability(FS_CAPABILITY_FREE_INDEX_DIR_COOKIE))
+		return B_OK;
+
 	// get a free port
 	RequestPort* port = fFileSystem->GetPortPool()->AcquirePort();
 	if (!port)
@@ -3052,6 +3267,10 @@ Volume::_FreeIndexDirCookie(fs_cookie cookie)
 status_t
 Volume::_CloseQuery(fs_cookie cookie)
 {
+	// check capability
+	if (!fFileSystem->HasCapability(FS_CAPABILITY_CLOSE_QUERY))
+		return B_OK;
+
 	// get a free port
 	RequestPort* port = fFileSystem->GetPortPool()->AcquirePort();
 	if (!port)
@@ -3086,6 +3305,10 @@ Volume::_CloseQuery(fs_cookie cookie)
 status_t
 Volume::_FreeQueryCookie(fs_cookie cookie)
 {
+	// check capability
+	if (!fFileSystem->HasCapability(FS_CAPABILITY_FREE_QUERY_COOKIE))
+		return B_OK;
+
 	// get a free port
 	RequestPort* port = fFileSystem->GetPortPool()->AcquirePort();
 	if (!port)

src/add-ons/kernel/file_systems/userlandfs/server/BeOSKernelFileSystem.cpp

@@ -4,6 +4,7 @@
 
 #include <new>
 
+#include "beos_fs_interface.h"
 #include "BeOSKernelVolume.h"
 
 using std::nothrow;
@@ -13,6 +14,7 @@ BeOSKernelFileSystem::BeOSKernelFileSystem(beos_vnode_ops* fsOps)
 	: FileSystem(),
 	  fFSOps(fsOps)
 {
+	_InitCapabilities(fsOps);
 }
 
 // destructor
@@ -45,3 +47,114 @@ BeOSKernelFileSystem::DeleteVolume(Volume* volume)
 	return B_OK;
 }
 
+// _InitCapabilities
+void
+BeOSKernelFileSystem::_InitCapabilities(beos_vnode_ops* fsOps)
+{
+	fCapabilities.ClearAll();
+
+	// FS interface type
+	fCapabilities.clientFSType = CLIENT_FS_BEOS_KERNEL;
+
+	// FS operations
+	fCapabilities.Set(FS_CAPABILITY_MOUNT, fsOps->mount);
+	fCapabilities.Set(FS_CAPABILITY_UNMOUNT, fsOps->unmount);
+
+	fCapabilities.Set(FS_CAPABILITY_READ_FS_INFO, fsOps->rfsstat);
+	fCapabilities.Set(FS_CAPABILITY_WRITE_FS_INFO, fsOps->wfsstat);
+	fCapabilities.Set(FS_CAPABILITY_SYNC, fsOps->sync);
+
+	// vnode operations
+	fCapabilities.Set(FS_CAPABILITY_LOOKUP, fsOps->walk);
+	// missing: FS_CAPABILITY_GET_VNODE_NAME,
+
+	fCapabilities.Set(FS_CAPABILITY_GET_VNODE, fsOps->read_vnode);
+	fCapabilities.Set(FS_CAPABILITY_PUT_VNODE, fsOps->write_vnode);
+	fCapabilities.Set(FS_CAPABILITY_REMOVE_VNODE, fsOps->remove_vnode);
+
+	// VM file access
+	// missing: FS_CAPABILITY_CAN_PAGE,
+	// missing: FS_CAPABILITY_READ_PAGES,
+	// missing: FS_CAPABILITY_WRITE_PAGES,
+
+	// cache file access
+	// missing: FS_CAPABILITY_GET_FILE_MAP,
+
+	// common operations
+	fCapabilities.Set(FS_CAPABILITY_IOCTL, fsOps->ioctl);
+	fCapabilities.Set(FS_CAPABILITY_SET_FLAGS, fsOps->setflags);
+	fCapabilities.Set(FS_CAPABILITY_SELECT, fsOps->select);
+	fCapabilities.Set(FS_CAPABILITY_DESELECT, fsOps->deselect);
+	fCapabilities.Set(FS_CAPABILITY_FSYNC, fsOps->fsync);
+
+	fCapabilities.Set(FS_CAPABILITY_READ_SYMLINK, fsOps->readlink);
+	fCapabilities.Set(FS_CAPABILITY_CREATE_SYMLINK, fsOps->symlink);
+
+	fCapabilities.Set(FS_CAPABILITY_LINK, fsOps->link);
+	fCapabilities.Set(FS_CAPABILITY_UNLINK, fsOps->unlink);
+	fCapabilities.Set(FS_CAPABILITY_RENAME, fsOps->rename);
+
+	fCapabilities.Set(FS_CAPABILITY_ACCESS, fsOps->access);
+	fCapabilities.Set(FS_CAPABILITY_READ_STAT, fsOps->rstat);
+	fCapabilities.Set(FS_CAPABILITY_WRITE_STAT, fsOps->wstat);
+
+	// file operations
+	fCapabilities.Set(FS_CAPABILITY_CREATE, fsOps->create);
+	fCapabilities.Set(FS_CAPABILITY_OPEN, fsOps->open);
+	fCapabilities.Set(FS_CAPABILITY_CLOSE, fsOps->close);
+	fCapabilities.Set(FS_CAPABILITY_FREE_COOKIE, fsOps->free_cookie);
+	fCapabilities.Set(FS_CAPABILITY_READ, fsOps->read);
+	fCapabilities.Set(FS_CAPABILITY_WRITE, fsOps->write);
+
+	// directory operations
+	fCapabilities.Set(FS_CAPABILITY_CREATE_DIR, fsOps->mkdir);
+	fCapabilities.Set(FS_CAPABILITY_REMOVE_DIR, fsOps->rmdir);
+	fCapabilities.Set(FS_CAPABILITY_OPEN_DIR, fsOps->opendir);
+	fCapabilities.Set(FS_CAPABILITY_CLOSE_DIR, fsOps->closedir);
+	fCapabilities.Set(FS_CAPABILITY_FREE_DIR_COOKIE, fsOps->free_dircookie);
+	fCapabilities.Set(FS_CAPABILITY_READ_DIR, fsOps->readdir);
+	fCapabilities.Set(FS_CAPABILITY_REWIND_DIR, fsOps->rewinddir);
+
+	// attribute directory operations
+	fCapabilities.Set(FS_CAPABILITY_OPEN_ATTR_DIR, fsOps->open_attrdir);
+	fCapabilities.Set(FS_CAPABILITY_CLOSE_ATTR_DIR, fsOps->close_attrdir);
+	fCapabilities.Set(FS_CAPABILITY_FREE_ATTR_DIR_COOKIE,
+		fsOps->free_attrdircookie);
+	fCapabilities.Set(FS_CAPABILITY_READ_ATTR_DIR, fsOps->read_attrdir);
+	fCapabilities.Set(FS_CAPABILITY_REWIND_ATTR_DIR, fsOps->rewind_attrdir);
+
+	// attribute operations
+	// we emulate open_attr() and free_attr_dir_cookie() if either read_attr()
+	// or write_attr() is present
+	bool hasAttributes = (fsOps->read_attr || fsOps->write_attr);
+	fCapabilities.Set(FS_CAPABILITY_CREATE_ATTR, hasAttributes);
+	fCapabilities.Set(FS_CAPABILITY_OPEN_ATTR, hasAttributes);
+	fCapabilities.Set(FS_CAPABILITY_CLOSE_ATTR, false);
+	fCapabilities.Set(FS_CAPABILITY_FREE_ATTR_COOKIE, hasAttributes);
+	fCapabilities.Set(FS_CAPABILITY_READ_ATTR, fsOps->read_attr);
+	fCapabilities.Set(FS_CAPABILITY_WRITE_ATTR, fsOps->write_attr);
+
+	fCapabilities.Set(FS_CAPABILITY_READ_ATTR_STAT, fsOps->stat_attr);
+	// missing: FS_CAPABILITY_WRITE_ATTR_STAT
+	fCapabilities.Set(FS_CAPABILITY_RENAME_ATTR, fsOps->rename_attr);
+	fCapabilities.Set(FS_CAPABILITY_REMOVE_ATTR, fsOps->remove_attr);
+
+	// index directory & index operations
+	fCapabilities.Set(FS_CAPABILITY_OPEN_INDEX_DIR, fsOps->open_indexdir);
+	fCapabilities.Set(FS_CAPABILITY_CLOSE_INDEX_DIR, fsOps->close_indexdir);
+	fCapabilities.Set(FS_CAPABILITY_FREE_INDEX_DIR_COOKIE,
+		fsOps->free_indexdircookie);
+	fCapabilities.Set(FS_CAPABILITY_READ_INDEX_DIR, fsOps->read_indexdir);
+	fCapabilities.Set(FS_CAPABILITY_REWIND_INDEX_DIR, fsOps->rewind_indexdir);
+
+	fCapabilities.Set(FS_CAPABILITY_CREATE_INDEX, fsOps->create_index);
+	fCapabilities.Set(FS_CAPABILITY_REMOVE_INDEX, fsOps->remove_index);
+	fCapabilities.Set(FS_CAPABILITY_READ_INDEX_STAT, fsOps->stat_index);
+
+	// query operations
+	fCapabilities.Set(FS_CAPABILITY_OPEN_QUERY, fsOps->open_query);
+	fCapabilities.Set(FS_CAPABILITY_CLOSE_QUERY, fsOps->close_query);
+	fCapabilities.Set(FS_CAPABILITY_FREE_QUERY_COOKIE, fsOps->free_querycookie);
+	fCapabilities.Set(FS_CAPABILITY_READ_QUERY, fsOps->read_query);
+	// missing: FS_CAPABILITY_REWIND_QUERY,
+}

src/add-ons/kernel/file_systems/userlandfs/server/BeOSKernelFileSystem.h

@@ -17,6 +17,9 @@ public:
 	virtual	status_t			CreateVolume(Volume** volume, mount_id id);
 	virtual	status_t			DeleteVolume(Volume* volume);
 
+private:
+			void				_InitCapabilities(beos_vnode_ops* fsOps);
+
 private:
 			beos_vnode_ops*		fFSOps;
 };

src/add-ons/kernel/file_systems/userlandfs/server/BeOSKernelVolume.cpp

@@ -294,7 +294,7 @@ status_t
 BeOSKernelVolume::Access(fs_vnode node, int mode)
 {
 	if (!fFSOps->access)
-		return B_BAD_VALUE;
+		return B_OK;
 	return fFSOps->access(fVolumeCookie, node, mode);
 }
 

src/add-ons/kernel/file_systems/userlandfs/server/FSInfo.h

@@ -9,6 +9,7 @@
 
 #include <Message.h>
 
+#include "FSCapabilities.h"
 #include "Port.h"
 #include "String.h"
 
@@ -25,12 +26,13 @@ public:
 	{
 	}
 
-	FSInfo(const char* fsName, const Port::Info* infos, int32 count)
+	FSInfo(const char* fsName, const Port::Info* infos, int32 count,
+		const FSCapabilities& capabilities)
 		: fName(),
 		  fInfos(NULL),
 		  fCount(0)
 	{
-		SetTo(fsName, infos, count);
+		SetTo(fsName, infos, count, capabilities);
 	}
 
 	FSInfo(const BMessage* message)
@@ -46,7 +48,7 @@ public:
 		  fInfos(NULL),
 		  fCount(0)
 	{
-		SetTo(other.GetName(), other.fInfos, other.fCount);
+		SetTo(other.GetName(), other.fInfos, other.fCount, other.fCapabilities);
 	}
 
 	~FSInfo()
@@ -54,17 +56,24 @@ public:
 		Unset();
 	}
 
-	status_t SetTo(const char* fsName, const Port::Info* infos, int32 count)
+	status_t SetTo(const char* fsName, const Port::Info* infos, int32 count,
+		const FSCapabilities& capabilities)
 	{
 		Unset();
+
 		if (!fsName || !infos || count <= 0)
 			return B_BAD_VALUE;
+
 		if (!fName.SetTo(fsName))
 			return B_NO_MEMORY;
+
 		fInfos = new(nothrow) Port::Info[count];
 		if (!fInfos)
 			return B_NO_MEMORY;
 		memcpy(fInfos, infos, sizeof(Port::Info) * count);
+
+		fCapabilities = capabilities;
+		
 		fCount = count;
 		return B_OK;
 	}
@@ -72,17 +81,25 @@ public:
 	status_t SetTo(const BMessage* message)
 	{
 		Unset();
+
 		if (!message)
 			return B_BAD_VALUE;
+
 		const void* infos;
 		ssize_t size;
 		const char* fsName;
+		const void* capabilities;
+		ssize_t capabilitiesSize;
+		
 		if (message->FindData("infos", B_RAW_TYPE, &infos, &size) != B_OK
-			|| size < 0 || message->FindString("fsName", &fsName) != B_OK) {
+			|| size < 0 || message->FindString("fsName", &fsName) != B_OK
+			|| message->FindData("capabilities", B_RAW_TYPE, &capabilities,
+				&capabilitiesSize) != B_OK
+			|| capabilitiesSize != sizeof(FSCapabilities)) {
 			return B_BAD_VALUE;
 		}
 		return SetTo(fsName, (const Port::Info*)infos,
-			size / sizeof(Port::Info));
+			size / sizeof(Port::Info), *(const FSCapabilities*)capabilities);
 	}
 
 	void Unset()
@@ -108,26 +125,39 @@ public:
 		return fCount;
 	}
 
-	int32 GetSize() const
+	int32 GetInfosSize() const
 	{
 		return fCount * sizeof(Port::Info);
 	}
 
+	const FSCapabilities& GetCapabilities() const
+	{
+		return fCapabilities;
+	}
+
 	status_t Archive(BMessage* archive)
 	{
 		if (!fName.GetString() || !fInfos)
 			return B_NO_INIT;
+
 		status_t error = archive->AddString("fsName", fName.GetString());
 		if (error != B_OK)
 			return error;
-		return archive->AddData("infos", B_RAW_TYPE, fInfos,
+
+		error = archive->AddData("infos", B_RAW_TYPE, fInfos,
 			fCount * sizeof(Port::Info));
+		if (error != B_OK)
+			return error;
+
+		return archive->AddData("capabilities", B_RAW_TYPE, &fCapabilities,
+			sizeof(FSCapabilities));
 	}
 
 private:
 	String			fName;
 	Port::Info*		fInfos;
 	int32			fCount;
+	FSCapabilities	fCapabilities;
 };
 
 }	// namespace UserlandFS

src/add-ons/kernel/file_systems/userlandfs/server/FileSystem.h

@@ -6,6 +6,8 @@
 #include <fs_interface.h>
 #include <SupportDefs.h>
 
+#include "FSCapabilities.h"
+
 namespace UserlandFS {
 
 class Volume;
@@ -17,6 +19,13 @@ public:
 
 	virtual	status_t			CreateVolume(Volume** volume, mount_id id) = 0;
 	virtual	status_t			DeleteVolume(Volume* volume) = 0;
+
+			void				GetCapabilities(
+									FSCapabilities& capabilities) const
+									{ capabilities = fCapabilities; }
+
+protected:
+			FSCapabilities		fCapabilities;
 };
 
 }	// namespace UserlandFS

src/add-ons/kernel/file_systems/userlandfs/server/UserlandFSDispatcher.cpp

@@ -319,6 +319,7 @@ UserlandFSDispatcher::_ProcessRequests()
 		if (error != B_OK)
 			RETURN_ERROR(error);
 		RequestReleaser _(fRequestPort, request);
+
 		// check the request type
 		if (request->GetType() == UFS_DISCONNECT_REQUEST)
 			return B_OK;
@@ -326,6 +327,7 @@ UserlandFSDispatcher::_ProcessRequests()
 			RETURN_ERROR(B_BAD_VALUE);
 		PRINT(("UserlandFSDispatcher::_ProcessRequests(): received FS connect "
 			"request\n"));
+
 		// it's an FS connect request
 		FSConnectRequest* connectRequest = (FSConnectRequest*)request;
 		// get the FS name
@@ -338,24 +340,27 @@ UserlandFSDispatcher::_ProcessRequests()
 			fsName.SetTo((const char*)connectRequest->fsName.GetData(), len);
 		if (result == B_OK && fsName.GetLength() == 0)
 			result = B_BAD_DATA;
+
 		// prepare the reply
 		RequestAllocator allocator(fRequestPort->GetPort());
 		FSConnectReply* reply;
 		error = AllocateRequest(allocator, &reply);
 		if (error != B_OK)
 			RETURN_ERROR(error);
+
 		FileSystem* fileSystem = NULL;
 		if (result == B_OK)
 			result = _GetFileSystem(fsName.GetString(), &fileSystem);
 		if (result == B_OK) {
 			const FSInfo* info = fileSystem->GetInfo();
 			result = allocator.AllocateData(reply->portInfos,
-				info->GetInfos(), info->GetSize(), sizeof(Port::Info));
+				info->GetInfos(), info->GetInfosSize(), sizeof(Port::Info));
-			if (result == B_OK)
+			reply->portInfoCount = info->CountInfos();
-				reply->portInfoCount = info->CountInfos();
+			reply->capabilities = info->GetCapabilities();
 			_PutFileSystem(fileSystem);
 		}
 		reply->error = result;
+
 		// send it
 		error = fRequestPort->SendRequest(&allocator);
 		if (error != B_OK)

src/add-ons/kernel/file_systems/userlandfs/server/UserlandFSServer.cpp

@@ -183,20 +183,29 @@ UserlandFSServer::_RegisterWithDispatcher(const char* fsName)
 		ERROR(("Failed to lock the clipboard.\n"));
 		return B_ERROR;
 	}
+
 	// get the port infos
 	Port::Info infos[kRequestThreadCount + 1];
 	infos[0] = *fNotificationRequestPort->GetPortInfo();
 	for (int32 i = 0; i < kRequestThreadCount; i++)
 		infos[i + 1] = *fRequestThreads[i].GetPortInfo();
+
+	// FS capabilities
+	FSCapabilities capabilities;
+	fFileSystem->GetCapabilities(capabilities);
+
 	// init an FS info
 	FSInfo info;
-	status_t error = info.SetTo(fsName, infos, kRequestThreadCount + 1);
+	status_t error = info.SetTo(fsName, infos, kRequestThreadCount + 1,
+		capabilities);
+
 	// prepare the message
 	BMessage message(UFS_REGISTER_FS);
 	if (error == B_OK)
 		error = message.AddInt32("team", Team());
 	if (error == B_OK)
 		error = info.Archive(&message);
+
 	// send the message
 	BMessage reply;
 	error = messenger.SendMessage(&message, &reply);