fs.c

pebble

/* 
 * Copyright 1999, 2000, 2001, 2002 Lucent Technologies Inc.
 * All Rights Reserved.
 * Information Sciences Research Center, Bell Labs.
 *
 * LUCENT TECHNOLOGIES DOES NOT CLAIM MERCHANTABILITY OF THIS SOFTWARE 
 * OR THE SUITABILITY OF THIS SOFTWARE FOR ANY PARTICULAR PURPOSE. The
 * software is provided "as is" without expressed or implied warranty 
 * of any kind.
 *
 * These notices must be retained in any copies of any part of this
 * software.
 *
 */

/*
 * A user-level file system mock-up.
 */

#include "string.h"
#include "pebble.h"
#include "synch.h"

#define	N		1024
#define	SHM_SIZE	(1024*1024)

static void *page[N];

const char PORTAL_CREATE[] = "too many open portals";

int
fs_write1(Thread *t, char *buf, int n)
{
	printf("fs_write: buf=%p n=%d asid=%d\n", buf, n, get_asid());
	printf("touching buf[0]=%d\n", (uchar)buf[0]);

	return n;
}


int
fs_read1(Thread *t, char *buf, int n)
{
	printf("fs_read: buf=%p n=%d\n", buf, n);
	buf[0]++;
	printf("new buf[0]=%d\n", (uchar)buf[0]);
	return n;
}


int
fs_write2(Thread *t, char *buf, int n)
{
	return n;
}


int
fs_read2(Thread *t, char *buf, int n)
{
	buf[0]++;
	return n;
}

int
fs_give(Thread *t, void *p, int i)
{
	if (i >= 0 && i < N)
		page[i] = p;

	return 0;
}

int
fs_peek(Thread *t, int *p)
{
	return *p;
}

int
fs_take(int caller_asid, int i)
{
	int code = -1;

	if (i >= 0 && i < N)
		code = vm_give_page(caller_asid, page[i]);

	if (code < 0)
		return -1;
	else
		return (int)page[i];
}

int
fs_swap(Thread *t, void *p, int i)
{
	int code = -1;

	if (i >= 0 && i < N)
		code = vm_swap_page(p, page[i]);

	return code;
}

int
fs_try(Thread *t, Lock *lock)
{
	return mutex_trylock(lock);
}


int
fs_share(Thread *t, void *p)
{
	return 0;
}

int
fs_set(Thread *t, int *p, int val)
{
	*p = val;

	return 0;
}

int
fs_unmap(Thread *t, void *p)
{
	return vm_unmap_page(p);
}

int
fs_count(Thread *t, void *p)
{
	return vm_count_page(p);
}

/* main file system thread */
int main()
{
	int x;	/* debug */
	int s, sz;
	char *addr;
	int give_id, window_peek_id, peek_id, take_id, swap_id, try_id;
	int set_id, share_id, unmap_id, count_id;

	printf("fs is active. asid=%d stack at %p\n", get_asid(), &x);

	/* verify that we are running in user mode with interrupts enabled */
	if (!check_psw(1,1)) {
		printf("fs: invalid processor status: %08lx\n", get_psw());
		task_exit(1);
	}

	if ((s = sem_create(1)) < 0)
		panic("sem_create:");
	if (sem_name(s, "fs_sem") < 0)
		panic("sem_name(fs_sem):");

	if (portal_create_pair_template("fs1", fs_read1, fs_write1, "smtwi", 0)
	    < 0)
		panic("portal_create_pair:");
	if (portal_create_pair_template("fs2", fs_read2, fs_write2, "smtwi", 0)
            < 0)
		panic("portal_create_pair:");

	if ((give_id = portal_create(-1, "smt>ii", 0, fs_give, 0)) < 0)
		panic("portal_create of fs_give:");
	if (portal_name(give_id, "fs_give", 1) < 0)
		panic("portal_name of fs_give:");

	if ((peek_id = portal_create(-1, "smtiii", 0, fs_peek, 0)) < 0)
		panic("portal_create of fs_peek:");
	if (portal_name(peek_id, "fs_peek", 1) < 0)
		panic("portal_name of fs_peek:");

	if ((window_peek_id = portal_create(-1, "smtwii", 0, fs_peek, 0)) < 0)
		panic("portal_create of fs_window_peek:");
	if (portal_name(window_peek_id, "fs_window_peek", 1) < 0)
		panic("portal_name of fs_peek:");

	if ((take_id = portal_create(-1, "smaiii", 0, fs_take, 0)) < 0)
		panic("portal_create of fs_take:");
	if (portal_name(take_id, "fs_take", 1) < 0)
		panic("portal_name of fs_take:");

	if ((swap_id = portal_create(-1, "smtwii", 0, fs_swap, 0)) < 0)
		panic("portal_create of fs_swap:");
	if (portal_name(swap_id, "fs_swap", 1) < 0)
		panic("portal_name of fs_swap:");

	if ((try_id = portal_create(-1, "smtiii", 0, fs_try, 0)) < 0)
		panic("portal_create of fs_try:");
	if (portal_name(try_id, "fs_try", 1) < 0)
		panic("portal_name of fs_try:");

	if ((share_id = portal_create(-1, "smt=ii", 0, fs_share, 0)) < 0)
		panic("portal_create of fs_share:");
	if (portal_name(share_id, "fs_share", 1) < 0)
		panic("portal_name of fs_share:");

	if ((set_id = portal_create(-1, "smtiii", 0, fs_set, 0)) < 0)
		panic("portal_create of fs_set:");
	if (portal_name(set_id, "fs_set", 1) < 0)
		panic("portal_name of fs_set:");

	if ((unmap_id = portal_create(-1, "smtiii", 0, fs_unmap, 0)) < 0)
		panic("portal_create of fs_unmap:");
	if (portal_name(unmap_id, "fs_unmap", 1) < 0)
		panic("portal_name of fs_unmap:");

	if ((count_id = portal_create(-1, "smtiii", 0, fs_count, 0)) < 0)
		panic("portal_create of fs_count:");
	if (portal_name(count_id, "fs_count", 1) < 0)
		panic("portal_name of fs_count:");

	if ((s = sem_create(0)) < 0)
		panic("sem_create");

	if ((addr = shm_create(SHM_SIZE)) == (char *)-1)
		panic("shm_create:");
	if (shm_name(addr, "shared") < 0)
		panic("shm_name:");
	if ((sz = shm_size(addr)) != SHM_SIZE) {
		printf("shm_size returned %d; should be %d\n", sz, SHM_SIZE);
		perror("shm_size");
		task_exit(1);
	}
	printf("shared area start=%p size=%d\n", addr, sz);

	printf("fs waiting forever...\n");
	/* wait forever */
	sem_wait(s);
	/*
	 * return to initialization code.
	 * cannot just "return", since the startup code (crt0.S) calls
	 * exit when main routine terminates.
	 */
	call_portal(SYS_RTN_RPC);
	return(1);
}