153 lines
		
	
	
		
			4.0 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			153 lines
		
	
	
		
			4.0 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* VTreeFS - vtreefs.c - by Alen Stojanov and David van Moolenbroek */
 | |
| 
 | |
| #include "inc.h"
 | |
| 
 | |
| FORWARD _PROTOTYPE( int get_work, (void)				);
 | |
| FORWARD _PROTOTYPE( void send_reply, (int err)				);
 | |
| FORWARD _PROTOTYPE( void got_signal, (int signal)			);
 | |
| 
 | |
| PRIVATE unsigned int inodes;
 | |
| PRIVATE struct inode_stat *root_stat;
 | |
| PRIVATE index_t root_entries;
 | |
| 
 | |
| /*===========================================================================*
 | |
|  *				init_server				     *
 | |
|  *===========================================================================*/
 | |
| PRIVATE int init_server(int UNUSED(type), sef_init_info_t *UNUSED(info))
 | |
| {
 | |
| 	/* Initialize internal state, and register with VFS.
 | |
| 	 */
 | |
| 	int r;
 | |
| 
 | |
| 	/* Initialize the virtual tree. */
 | |
| 	init_inodes(inodes, root_stat, root_entries);
 | |
| 
 | |
| 	/* Tell VFS that we are here. */
 | |
| 	fs_m_out.m_type = FS_READY;
 | |
| 
 | |
| 	if ((r = send(VFS_PROC_NR, &fs_m_out)) != OK)
 | |
| 		panic(__FILE__, "error sending login to VFS", r);
 | |
| 
 | |
| 	/* Do not yet allow any requests except REQ_READSUPER. */
 | |
| 	fs_mounted = FALSE;
 | |
| 
 | |
| 	return OK;
 | |
| }
 | |
| 
 | |
| /*===========================================================================*
 | |
|  *				sef_local_startup			     *
 | |
|  *===========================================================================*/
 | |
| PRIVATE void sef_local_startup(void)
 | |
| {
 | |
| 	sef_setcb_init_fresh(init_server);
 | |
| 	sef_setcb_init_restart(init_server);
 | |
| 
 | |
| 	sef_setcb_signal_handler(got_signal);
 | |
| 
 | |
| 	/* No support for live update yet. */
 | |
| 
 | |
| 	sef_startup();
 | |
| }
 | |
| 
 | |
| /*===========================================================================*
 | |
|  *				start_vtreefs				     *
 | |
|  *===========================================================================*/
 | |
| PUBLIC void start_vtreefs(struct fs_hooks *hooks, unsigned int nr_inodes,
 | |
| 		struct inode_stat *stat, index_t nr_indexed_entries)
 | |
| {
 | |
| 	/* This is the main routine of this service. The main loop consists of
 | |
| 	 * three major activities: getting new work, processing the work, and
 | |
| 	 * sending the reply. The loop exits when the process is signaled to
 | |
| 	 * exit; due to limitations of SEF, it can not return to the caller.
 | |
| 	 */
 | |
| 	int call_nr, err;
 | |
| 
 | |
| 	/* Use global variables to work around the inability to pass parameters
 | |
| 	 * through SEF to the initialization function..
 | |
| 	 */
 | |
| 	vtreefs_hooks = hooks;
 | |
| 	inodes = nr_inodes;
 | |
| 	root_stat = stat;
 | |
| 	root_entries = nr_indexed_entries;
 | |
| 
 | |
| 	sef_local_startup();
 | |
| 
 | |
| 	for (;;) {
 | |
| 		call_nr = get_work();
 | |
| 
 | |
| 		if (fs_m_in.m_source != VFS_PROC_NR) {
 | |
| 			if (vtreefs_hooks->message_hook != NULL) {
 | |
| 				/* If the request is not among the recognized
 | |
| 				 * requests, call the message hook.
 | |
| 				 */
 | |
| 				vtreefs_hooks->message_hook(&fs_m_in);
 | |
| 			}
 | |
| 
 | |
| 			continue;
 | |
| 		}
 | |
| 
 | |
| 		if (fs_mounted || call_nr == REQ_READSUPER) {
 | |
| 			call_nr -= VFS_BASE;
 | |
| 
 | |
| 			if (call_nr >= 0 && call_nr < NREQS) {
 | |
| 				err = (*fs_call_vec[call_nr])();
 | |
| 			} else {
 | |
| 				err = ENOSYS;
 | |
| 			}
 | |
| 		}
 | |
| 		else err = EINVAL;
 | |
| 
 | |
| 		send_reply(err);
 | |
| 	}
 | |
| }
 | |
| 
 | |
| /*===========================================================================*
 | |
|  *				get_work				     *
 | |
|  *===========================================================================*/
 | |
| PRIVATE int get_work(void)
 | |
| {
 | |
| 	/* Retrieve work. Return the call number.
 | |
| 	 */
 | |
| 	int r;
 | |
| 
 | |
| 	if ((r = sef_receive(ANY, &fs_m_in)) != OK)
 | |
| 		panic(__FILE__, "receive failed", r);
 | |
| 
 | |
| 	return fs_m_in.m_type;
 | |
| }
 | |
| 
 | |
| /*===========================================================================*
 | |
|  *				send_reply				     *
 | |
|  *===========================================================================*/
 | |
| PRIVATE void send_reply(int err)
 | |
| {
 | |
| 	/* Send a reply to the caller.
 | |
| 	 */
 | |
| 	int r;
 | |
| 
 | |
| 	fs_m_out.m_type = err;
 | |
| 
 | |
| 	if ((r = send(fs_m_in.m_source, &fs_m_out)) != OK)
 | |
| 		panic(__FILE__, "unable to send reply", r);
 | |
| }
 | |
| 
 | |
| /*===========================================================================*
 | |
|  *				got_signal				     *
 | |
|  *===========================================================================*/
 | |
| PRIVATE void got_signal(int signal)
 | |
| {
 | |
| 	/* We received a signal. If it is a termination signal, and the file
 | |
| 	 * system has already been unmounted, clean up and exit.
 | |
| 	 */
 | |
| 
 | |
| 	if (signal != SIGTERM)
 | |
| 		return;
 | |
| 
 | |
| 	if (fs_mounted)
 | |
| 		return;
 | |
| 
 | |
| 	cleanup_inodes();
 | |
| 
 | |
| 	exit(0);
 | |
| }
 | 
