text: /*
   * Copyright 2002-2018, Axel Dörfler, axeld@pinc-software.de.
   * Distributed under the terms of the MIT License.
   *
   * Copyright 2001-2002, Travis Geiselbrecht. All rights reserved.
   * Distributed under the terms of the NewOS License.
   */
  #ifndef _KERNEL_VFS_H
  #define _KERNEL_VFS_H
  
  
  #include <kernel.h>
  #include <lock.h>
  #include <util/list.h>
  
  #include <fs_interface.h>
  
  #include <dirent.h>
  #include <signal.h>
  #include <sys/socket.h>
  #include <sys/stat.h>
  #include <sys/select.h>
  
  #include <vfs_defs.h>
  
  
  #define DEFAULT_FD_TABLE_SIZE	256
  #define MAX_FD_TABLE_SIZE		8192
  #define DEFAULT_NODE_MONITORS	4096
  #define MAX_NODE_MONITORS		65536
  
  #define B_UNMOUNT_BUSY_PARTITION	0x80000000
  
  struct attr_info;
  struct file_descriptor;
  struct generic_io_vec;
  struct kernel_args;
  struct net_stat;
  struct pollfd;
  struct rlimit;
  struct selectsync;
  struct select_info;
  struct VMCache;
  struct vnode;
  
  
  /** The I/O context of a process/team, holds the fd array among others */
  typedef struct io_context {
  	struct vnode *root;
  	struct vnode *cwd;
  	mutex		io_mutex;
  	int32		ref_count;
  	uint32		table_size;
  	uint32		num_used_fds;
  	struct file_descriptor **fds;
  	struct select_info **select_infos;
  	uint8		*fds_close_on_exec;
  	struct list node_monitors;
  	uint32		num_monitors;
  	uint32		max_monitors;
  	bool		inherit_fds;
  } io_context;
  
  
  #ifdef __cplusplus
  extern "C" {
  #endif
  
  status_t	vfs_init(struct kernel_args *args);
  status_t	vfs_bootstrap_file_systems(void);
  void		vfs_mount_boot_file_system(struct kernel_args *args);
  void		vfs_exec_io_context(io_context *context);
  io_context*	vfs_new_io_context(io_context* parentContext,
  				bool purgeCloseOnExec);
  void		vfs_get_io_context(io_context *context);
  void		vfs_put_io_context(io_context *context);
  status_t	vfs_resize_fd_table(struct io_context* context, uint32 newSize);
  
  int			vfs_getrlimit(int resource, struct rlimit *rlp);
  int			vfs_setrlimit(int resource, const struct rlimit *rlp);
  
  /* calls needed by the VM for paging and by the file cache */
  status_t	vfs_get_vnode_from_fd(int fd, bool kernel, struct vnode **_vnode);
  status_t	vfs_get_vnode_from_path(const char *path, bool kernel,
  				struct vnode **_vnode);
  status_t	vfs_get_vnode(dev_t mountID, ino_t vnodeID, bool canWait,
  				struct vnode **_vnode);
  status_t	vfs_entry_ref_to_vnode(dev_t mountID, ino_t directoryID,
  				const char *name, struct vnode **_vnode);
  void		vfs_vnode_to_node_ref(struct vnode *vnode, dev_t *_mountID,
  				ino_t *_vnodeID);
  struct fs_vnode* vfs_fsnode_for_vnode(struct vnode* vnode);
  
  int			vfs_open_vnode(struct vnode* vnode, int openMode, bool kernel);
  status_t	vfs_lookup_vnode(dev_t mountID, ino_t vnodeID,
  				struct vnode **_vnode);
  void		vfs_put_vnode(struct vnode *vnode);
  void		vfs_acquire_vnode(struct vnode *vnode);
  status_t	vfs_get_cookie_from_fd(int fd, void **_cookie);
  bool		vfs_can_page(struct vnode *vnode, void *cookie);
  status_t	vfs_read_pages(struct vnode *vnode, void *cookie, off_t pos,
  				const struct generic_io_vec *vecs, size_t count, uint32 flags,
  				generic_size_t *_numBytes);
  status_t	vfs_write_pages(struct vnode *vnode, void *cookie, off_t pos,
  				const struct generic_io_vec *vecs, size_t count, uint32 flags,
  				generic_size_t *_numBytes);
  status_t	vfs_vnode_io(struct vnode* vnode, void* cookie,
  				io_request* request);
  status_t	vfs_synchronous_io(io_request* request,
  				status_t (*doIO)(void* cookie, off_t offset, void* buffer,
  					size_t* length),
  				void* cookie);
  status_t	vfs_get_vnode_cache(struct vnode *vnode, struct VMCache **_cache,
  				bool allocate);
  status_t	vfs_set_vnode_cache(struct vnode *vnode, struct VMCache *_cache);
  status_t	vfs_get_file_map(struct vnode *vnode, off_t offset, size_t size,
  				struct file_io_vec *vecs, size_t *_count);
  status_t	vfs_get_fs_node_from_path(fs_volume *volume, const char *path,
  				bool traverseLeafLink, bool kernel, void **_node);
  status_t	vfs_stat_vnode(struct vnode *vnode, struct stat *stat);
  status_t	vfs_stat_node_ref(dev_t device, ino_t inode, struct stat *stat);
  status_t	vfs_get_vnode_name(struct vnode *vnode, char *name,
  				size_t nameSize);
  status_t	vfs_entry_ref_to_path(dev_t device, ino_t inode, const char *leaf,
  				bool kernel, char *path, size_t pathLength);
  status_t	vfs_get_cwd(dev_t *_mountID, ino_t *_vnodeID);
  void		vfs_unlock_vnode_if_locked(struct file_descriptor *descriptor);
  status_t	vfs_release_posix_lock(io_context* context,
  				struct file_descriptor* descriptor);
  status_t	vfs_unmount(dev_t mountID, uint32 flags);
  status_t	vfs_disconnect_vnode(dev_t mountID, ino_t vnodeID);
  status_t	vfs_resolve_parent(struct vnode* parent, dev_t* device,
  				ino_t* node);
  void		vfs_free_unused_vnodes(int32 level);
  
  status_t	vfs_read_stat(int fd, const char *path, bool traverseLeafLink,
  				struct stat *stat, bool kernel);
  
  /* special module convenience call */
  status_t	vfs_get_module_path(const char *basePath, const char *moduleName,
  				char *pathBuffer, size_t bufferSize);
  
  /* service call for whoever needs a normalized path */
  status_t	vfs_normalize_path(const char *path, char *buffer,
  				size_t bufferSize, bool traverseLink, bool kernel);
  
  /* service call for whoever wants to create a special node */
  status_t	vfs_create_special_node(const char *path, fs_vnode *subVnode,
  				mode_t mode, uint32 flags, bool kernel, fs_vnode *_superVnode,
  				struct vnode **_createdVnode);
  
  /* service call for the node monitor */
  status_t	vfs_resolve_vnode_to_covering_vnode(dev_t mountID, ino_t nodeID,
  				dev_t *resolvedMountID, ino_t *resolvedNodeID);
  
  /* service calls for private file systems */
  status_t	vfs_get_mount_point(dev_t mountID, dev_t* _mountPointMountID,
  				ino_t* _mountPointNodeID);
  status_t	vfs_bind_mount_directory(dev_t mountID, ino_t nodeID,
  				dev_t coveredMountID, ino_t coveredNodeID);
  
  /* calls the syscall dispatcher should use for user file I/O */
  dev_t		_user_mount(const char *path, const char *device,
  				const char *fs_name, uint32 flags, const char *args,
  				size_t argsLength);
  status_t	_user_unmount(const char *path, uint32 flags);
  status_t	_user_read_fs_info(dev_t device, struct fs_info *info);
  status_t	_user_write_fs_info(dev_t device, const struct fs_info *info,
  				int mask);
  dev_t		_user_next_device(int32 *_cookie);
  status_t	_user_sync(void);
  status_t	_user_get_next_fd_info(team_id team, uint32 *cookie,
  				struct fd_info *info, size_t infoSize);
  status_t	_user_entry_ref_to_path(dev_t device, ino_t inode, const char *leaf,
  				char *userPath, size_t pathLength);
  status_t	_user_normalize_path(const char* userPath, bool traverseLink,
  				char* buffer);
  int			_user_open_entry_ref(dev_t device, ino_t inode, const char *name,
  				int openMode, int perms);
  int			_user_open(int fd, const char *path, int openMode, int perms);
  int			_user_open_dir_node_ref(dev_t device, ino_t inode);
  int			_user_open_dir_entry_ref(dev_t device, ino_t inode,
  				const char *name);
  int			_user_open_dir(int fd, const char *path);
  int			_user_open_parent_dir(int fd, char *name, size_t nameLength);
  status_t	_user_fcntl(int fd, int op, size_t argument);
  status_t	_user_fsync(int fd);
  status_t	_user_flock(int fd, int op);
  status_t	_user_read_stat(int fd, const char *path, bool traverseLink,
  				struct stat *stat, size_t statSize);
  status_t	_user_write_stat(int fd, const char *path, bool traverseLink,
  				const struct stat *stat, size_t statSize, int statMask);
  off_t		_user_seek(int fd, off_t pos, int seekType);
  status_t	_user_create_dir_entry_ref(dev_t device, ino_t inode,
  				const char *name, int perms);
  status_t	_user_create_dir(int fd, const char *path, int perms);
  status_t	_user_remove_dir(int fd, const char *path);
  status_t	_user_read_link(int fd, const char *path, char *buffer,
  				size_t *_bufferSize);
  status_t	_user_write_link(const char *path, const char *toPath);
  status_t	_user_create_symlink(int fd, const char *path, const char *toPath,
  				int mode);
  status_t	_user_create_link(int pathFD, const char *path, int toFD,
  				const char *toPath, bool traverseLeafLink);
  status_t	_user_unlink(int fd, const char *path);
  status_t	_user_rename(int oldFD, const char *oldpath, int newFD,
  				const char *newpath);
  status_t	_user_create_fifo(int fd, const char *path, mode_t perms);
  status_t	_user_create_pipe(int *fds);
  status_t	_user_access(int fd, const char *path, int mode,
  				bool effectiveUserGroup);
  ssize_t		_user_select(int numfds, fd_set *readSet, fd_set *writeSet,
  				fd_set *errorSet, bigtime_t timeout, const sigset_t *sigMask);
  ssize_t		_user_poll(struct pollfd *fds, int numfds, bigtime_t timeout);
  int			_user_open_attr_dir(int fd, const char *path,
  				bool traverseLeafLink);
  ssize_t		_user_read_attr(int fd, const char *attribute, off_t pos,
  				void *buffer, size_t readBytes);
  ssize_t		_user_write_attr(int fd, const char *attribute, uint32 type,
  				off_t pos, const void *buffer, size_t readBytes);
  status_t	_user_stat_attr(int fd, const char *attribute,
  				struct attr_info *attrInfo);
  int			_user_open_attr(int fd, const char* path, const char *name,
  				uint32 type, int openMode);
  status_t	_user_remove_attr(int fd, const char *name);
  status_t	_user_rename_attr(int fromFile, const char *fromName, int toFile,
  				const char *toName);
  int			_user_open_index_dir(dev_t device);
  status_t	_user_create_index(dev_t device, const char *name, uint32 type,
  				uint32 flags);
  status_t	_user_read_index_stat(dev_t device, const char *name,
  				struct stat *stat);
  status_t	_user_remove_index(dev_t device, const char *name);
  status_t	_user_getcwd(char *buffer, size_t size);
  status_t	_user_setcwd(int fd, const char *path);
  status_t	_user_change_root(const char *path);
  int			_user_open_query(dev_t device, const char *query,
  				size_t queryLength, uint32 flags, port_id port, int32 token);
  
  /* fd user prototypes (implementation located in fd.cpp)  */
  ssize_t		_user_read(int fd, off_t pos, void *buffer, size_t bufferSize);
  ssize_t		_user_readv(int fd, off_t pos, const iovec *vecs, size_t count);
  ssize_t		_user_write(int fd, off_t pos, const void *buffer,
  				size_t bufferSize);
  ssize_t		_user_writev(int fd, off_t pos, const iovec *vecs, size_t count);
  status_t	_user_ioctl(int fd, uint32 cmd, void *data, size_t length);
  ssize_t		_user_read_dir(int fd, struct dirent *buffer, size_t bufferSize,
  				uint32 maxCount);
  status_t	_user_rewind_dir(int fd);
  status_t	_user_close(int fd);
  int			_user_dup(int fd);
  int			_user_dup2(int ofd, int nfd);
  status_t	_user_lock_node(int fd);
  status_t	_user_unlock_node(int fd);
  
  /* socket user prototypes (implementation in socket.cpp) */
  int			_user_socket(int family, int type, int protocol);
  status_t	_user_bind(int socket, const struct sockaddr *address,
  				socklen_t addressLength);
  status_t	_user_shutdown_socket(int socket, int how);
  status_t	_user_connect(int socket, const struct sockaddr *address,
  				socklen_t addressLength);
  status_t	_user_listen(int socket, int backlog);
  int			_user_accept(int socket, struct sockaddr *address,
  				socklen_t *_addressLength);
  ssize_t		_user_recv(int socket, void *data, size_t length, int flags);
  ssize_t		_user_recvfrom(int socket, void *data, size_t length, int flags,
  				struct sockaddr *address, socklen_t *_addressLength);
  ssize_t		_user_recvmsg(int socket, struct msghdr *message, int flags);
  ssize_t		_user_send(int socket, const void *data, size_t length, int flags);
  ssize_t		_user_sendto(int socket, const void *data, size_t length, int flags,
  				const struct sockaddr *address, socklen_t addressLength);
  ssize_t		_user_sendmsg(int socket, const struct msghdr *message, int flags);
  status_t	_user_getsockopt(int socket, int level, int option, void *value,
  				socklen_t *_length);
  status_t	_user_setsockopt(int socket, int level, int option,
  				const void *value, socklen_t length);
  status_t	_user_getpeername(int socket, struct sockaddr *address,
  				socklen_t *_addressLength);
  status_t	_user_getsockname(int socket, struct sockaddr *address,
  				socklen_t *_addressLength);
  int			_user_sockatmark(int socket);
  status_t	_user_socketpair(int family, int type, int protocol,
  				int *socketVector);
  status_t	_user_get_next_socket_stat(int family, uint32 *cookie,
  				struct net_stat *stat);
  
  #ifdef __cplusplus
  }
  #endif
  
  
  #ifdef __cplusplus
  
  class AsyncIOCallback {
  public:
  	virtual						~AsyncIOCallback();
  
  	virtual	void				IOFinished(status_t status,
  									bool partialTransfer,
  									generic_size_t bytesTransferred) = 0;
  
  	static	status_t 			IORequestCallback(void* data,
  									io_request* request, status_t status,
  									bool partialTransfer,
  									generic_size_t transferEndOffset);
  };
  
  
  class StackableAsyncIOCallback : public AsyncIOCallback {
  public:
  								StackableAsyncIOCallback(AsyncIOCallback* next);
  
  protected:
  			AsyncIOCallback*	fNextCallback;
  };
  
  
  status_t	vfs_asynchronous_read_pages(struct vnode* vnode, void* cookie,
  				off_t pos, const struct generic_io_vec* vecs, size_t count,
  				generic_size_t numBytes, uint32 flags,
  				AsyncIOCallback* callback);
  
  status_t	vfs_asynchronous_write_pages(struct vnode* vnode, void* cookie,
  				off_t pos, const struct generic_io_vec* vecs, size_t count,
  				generic_size_t numBytes, uint32 flags,
  				AsyncIOCallback* callback);
  
  #endif	// __cplusplus
  
  #endif	/* _KERNEL_VFS_H */
  