/* Read real device (Non-virtual). Will repeat 3 times if needed */
static SIZE_OR_ERROR FS_read_real(struct one_wire_query *owq)
{
struct parsedname *pn = PN(owq);
SIZE_OR_ERROR read_or_error;
/* First try */
/* in and bus_nr already set */
read_or_error = FS_read_distribute(owq);
/* Second Try */
/* if not a specified bus, relook for chip location */
if (read_or_error < 0) { //error
STAT_ADD1(read_tries[1]);
if (SpecifiedBus(pn)) { // this bus or bust!
if ( BAD(TestConnection(pn)) ) {
read_or_error = -ECONNABORTED;
} else {
read_or_error = FS_read_distribute(owq); // 2nd try
if (read_or_error < 0) { // third try
STAT_ADD1(read_tries[2]);
read_or_error = FS_read_distribute(owq);
}
}
} else if (BusIsServer(pn->selected_connection)) {
int bus_nr = pn->selected_connection->index ; // current selected bus
INDEX_OR_ERROR busloc_or_error = ReCheckPresence(pn) ;
// special handling or remote
// only repeat if the bus number is wrong
// because the remote does the rereads
if ( bus_nr != busloc_or_error ) {
if (busloc_or_error < 0) {
read_or_error = -ENOENT;
} else {
read_or_error = FS_read_distribute(owq);
if (read_or_error < 0) { // third try
STAT_ADD1(read_tries[2]);
read_or_error = FS_read_distribute(owq);
}
}
}
} else {
INDEX_OR_ERROR busloc_or_error = ReCheckPresence(pn); // search again
if (busloc_or_error < 0) {
read_or_error = -ENOENT;
} else {
read_or_error = FS_read_distribute(owq);
if (read_or_error < 0) { // third try
STAT_ADD1(read_tries[2]);
read_or_error = FS_read_distribute(owq);
}
}
}
}
return read_or_error;
}
/* If error, try twice more */
static ZERO_OR_ERROR FS_write_real(int depth, struct one_wire_query *owq)
{
ZERO_OR_ERROR write_or_error;
struct parsedname *pn = PN(owq);
struct filetype * ft = pn->selected_filetype ;
INDEX_OR_ERROR initial_bus = pn->selected_connection->index ; // current selected bus
INDEX_OR_ERROR rechecked_bus ;
if ( depth > 1 ) {
LEVEL_DEBUG("Too many bus changes for write");
return -ENODEV ;
}
if ( ft->write == FS_w_alias ) {
// Special check for alias
// it's ok for fake and tester and mock as well
// so do this before the fake test
// also no need to three-peat.
return FS_write_owq(owq) ;
}
/* Special case for "fake" adapter */
switch (get_busmode(pn->selected_connection)) {
case bus_mock:
// Mock -- write even "unwritable" to the cache for testing
OWQ_Cache_Add(owq) ;
// fall through
case bus_fake:
case bus_tester:
return ( ft->write == NO_WRITE_FUNCTION ) ? -ENOTSUP : 0 ;
default:
// non-virtual devices get handled below
break ;
}
/* First try */
/* in and bus_nr already set */
STAT_ADD1(write_tries[0]);
write_or_error = FS_w_given_bus(owq);
if ( write_or_error ==0 ) {
return 0 ;
}
/* Second Try */
STAT_ADD1(write_tries[1]);
if (SpecifiedBus(pn)) {
// The bus number casn't be changed -- it was specified in the path
write_or_error = FS_w_given_bus(owq);
if ( write_or_error == 0 ) {
return 0 ;
}
// The bus number casn't be changed -- it was specified in the path
STAT_ADD1(write_tries[2]);
return FS_w_given_bus(owq);
}
/* Recheck location */
/* if not a specified bus, relook for chip location */
rechecked_bus = ReCheckPresence(pn) ;
if ( rechecked_bus < 0 ) {
// can't find the location
return -ENOENT ;
}
if ( initial_bus == rechecked_bus ) {
// special handling for remote
// only repeat if the bus number is wrong
// because the remote does the rewrites
if (BusIsServer(pn->selected_connection)) {
return write_or_error ;
}
// try again
STAT_ADD1(write_tries[1]);
write_or_error = FS_w_given_bus(owq);
if ( write_or_error == 0 ) {
return 0 ;
}
// third try
STAT_ADD1(write_tries[2]);
return FS_w_given_bus(owq);
}
// Changed location retry everything
LEVEL_DEBUG("Bus location changed from %d to %d\n",initial_bus,rechecked_bus);
return FS_write_real(depth+1,owq);
}
