int
host_read(uint32_t secno, void *dst, size_t nsecs)
{
int r, read = 0;
if(host_fd->fd_file.id == 0) {
host_ipc_init();
}
//This rewrites offset visible to host fs as well
host_fd->fd_offset = secno * SECTSIZE;
// read from the host, 2 sectors at a time.
for(; nsecs > 0; nsecs-=2) {
host_fsipcbuf.read.req_fileid = host_fd->fd_file.id;
host_fsipcbuf.read.req_n = SECTSIZE * 2;
if ((r = host_fsipc(FSREQ_READ, NULL)) < 0)
return r;
// FIXME: Handle case where r < SECTSIZE * 2;
memmove(dst+read, &host_fsipcbuf, r);
read += SECTSIZE * 2;
}
return 0;
}
int
host_write(uint32_t secno, const void *src, size_t nsecs)
{
int r, written = 0;
if(host_fd->fd_file.id == 0) {
host_ipc_init();
}
host_fd->fd_offset = secno * SECTSIZE;
for(; nsecs > 0; nsecs-=2) {
host_fsipcbuf.write.req_fileid = host_fd->fd_file.id;
host_fsipcbuf.write.req_n = SECTSIZE * 2;
memmove(host_fsipcbuf.write.req_buf, src+written, SECTSIZE * 2);
if ((r = host_fsipc(FSREQ_WRITE, NULL)) < 0)
return r;
written += SECTSIZE * 2;
}
return 0;
}
// Initialize the file system
void
fs_init(void)
{
static_assert(sizeof(struct File) == 256);
#ifndef VMM_GUEST
// Find a JOS disk. Use the second IDE disk (number 1) if available.
if (ide_probe_disk1())
ide_set_disk(1);
else
ide_set_disk(0);
#else
host_ipc_init();
#endif
bc_init();
// Set "super" to point to the super block.
super = diskaddr(1);
check_super();
// Set "bitmap" to the beginning of the first bitmap block.
bitmap = diskaddr(2);
check_bitmap();
}
