/* AMSTStressBufferedSeg -- Stress test for a buffered seg
*
* Test splitting or merging a buffered seg.
*
* .bmerge: A merge is performed when the segment had previously
* been split and the segment above meets the constraints (i.e. empty,
* not already attached to a buffer and similar colour)
*
* .bsplit: Whether or not a merge happpened, a split is performed if
* the limit of the buffered region is also the limit of an arena
* grain, and yet does not correspond to the segment limit, provided
* that the part of the segment above the buffer is all free.
*/
static void AMSTStressBufferedSeg(Seg seg, Buffer buffer)
{
AMSTSeg amstseg;
AMST amst;
Arena arena;
Addr limit;
Buffer segBuf;
AVERT(Seg, seg);
AVERT(Buffer, buffer);
AVER(SegBuffer(&segBuf, seg) && segBuf == buffer);
amstseg = Seg2AMSTSeg(seg);
AVERT(AMSTSeg, amstseg);
limit = BufferLimit(buffer);
arena = PoolArena(SegPool(seg));
amst = PoolAMST(SegPool(seg));
AVERT(AMST, amst);
if (amstseg->next != NULL) {
Seg segHi = AMSTSeg2Seg(amstseg->next);
if (AMSSegIsFree(segHi) && SegGrey(segHi) == SegGrey(seg)) {
/* .bmerge */
Seg mergedSeg;
Res res;
res = SegMerge(&mergedSeg, seg, segHi);
if (ResOK == res) {
amst->bmerges++;
printf("J");
} else {
/* deliberate fails only */
AVER(amst->failSegs);
}
}
}
if (SegLimit(seg) != limit &&
AddrIsArenaGrain(limit, arena) &&
AMSSegRegionIsFree(seg, limit, SegLimit(seg))) {
/* .bsplit */
Seg segLo, segHi;
Res res;
res = SegSplit(&segLo, &segHi, seg, limit);
if (ResOK == res) {
amst->bsplits++;
printf("C");
} else {
/* deliberate fails only */
AVER(amst->failSegs);
}
}
}
/* MVFFFreeSegs -- Free segments from given range
*
* Given a free range, attempts to find entire segments within
* it, and returns them to the arena, updating total size counter.
*
* This is usually called immediately after MVFFAddToFreeList.
* It is not combined with MVFFAddToFreeList because the latter
* is also called when new segments are added under MVFFAlloc.
*/
static void MVFFFreeSegs(MVFF mvff, Addr base, Addr limit)
{
Seg seg = NULL; /* suppress "may be used uninitialized" */
Arena arena;
Bool b;
Addr segLimit; /* limit of the current segment when iterating */
Addr segBase; /* base of the current segment when iterating */
Res res;
AVERT(MVFF, mvff);
AVER(base < limit);
/* Could profitably AVER that the given range is free, */
/* but the CBS doesn't provide that facility. */
if (AddrOffset(base, limit) < mvff->minSegSize)
return; /* not large enough for entire segments */
arena = PoolArena(MVFF2Pool(mvff));
b = SegOfAddr(&seg, arena, base);
AVER(b);
segBase = SegBase(seg);
segLimit = SegLimit(seg);
while(segLimit <= limit) { /* segment ends in range */
if (segBase >= base) { /* segment starts in range */
/* Must remove from free list first, in case free list */
/* is using inline data structures. */
res = CBSDelete(CBSOfMVFF(mvff), segBase, segLimit);
AVER(res == ResOK);
mvff->free -= AddrOffset(segBase, segLimit);
mvff->total -= AddrOffset(segBase, segLimit);
SegFree(seg);
}
/* Avoid calling SegNext if the next segment would fail */
/* the loop test, mainly because there might not be a */
/* next segment. */
if (segLimit == limit) /* segment ends at end of range */
break;
b = SegNext(&seg, arena, segBase);
AVER(b);
segBase = SegBase(seg);
segLimit = SegLimit(seg);
}
return;
}
static void segBufAttach(Buffer buffer, Addr base, Addr limit,
Addr init, Size size)
{
SegBuf segbuf = MustBeA(SegBuf, buffer);
Seg seg = NULL; /* suppress "may be used uninitialized" */
Arena arena;
Bool found;
/* Other parameters are consistency checked in BufferAttach */
UNUSED(init);
UNUSED(size);
arena = BufferArena(buffer);
found = SegOfAddr(&seg, arena, base);
AVER(found);
AVER(segbuf->seg == NULL);
AVER(!SegHasBuffer(seg));
AVER(SegBase(seg) <= base);
AVER(limit <= SegLimit(seg));
/* attach the buffer to the segment */
SegSetBuffer(seg, buffer);
segbuf->seg = seg;
AVERT(SegBuf, segbuf);
}
static int ReadWrite( int (*r)(word,dword,char*), addr48_ptr *addr, char *data, int req ) {
int len;
word segment;
dword offset;
offset = addr->offset;
segment = addr->segment;
_DBG2(("Read Write %4.4x:%8.8lx",segment,offset));
if( SegLimit( segment ) >= offset + req - 1 ) {
_DBG2(("Read Write Ok for %d", req));
if( !r( segment, offset, data ) ) {
segment = AltSegment( segment );
}
if( SegLimit( segment ) < offset + req - 1 ) {
_DBG3(("Gosh, we're in trouble dudes"));
if( SegLimit( segment ) == 0 ) {
_DBG3(("Gosh, we're in SERIOUS trouble dudes"));
}
} else {
len = req;
while( --len >= 0 ) {
if( !r( segment, offset++, data++ ) ) {
_DBG3(("failed for %4.4x:%8.8lx", segment, offset-1));
}
}
_DBG2(("Read Write Done"));
return( req );
}
}
len = 0;
_DBG2(("Read Write One byte at a time for %d", req));
while( --req >= 0 ) {
if( SegLimit( segment ) < offset ) break;
if( !r( segment, offset, data ) ) {
segment = AltSegment( segment );
}
if( !r( segment, offset++, data++ ) ) {
_DBG3(("failed for %4.4x:%8.8lx", segment, offset-1));
}
++len;
}
_DBG2(("Read Write Done"));
return( len );
}
static Res MVFFAlloc(Addr *aReturn, Pool pool, Size size,
Bool withReservoirPermit, DebugInfo info)
{
Res res;
MVFF mvff;
Addr base, limit;
Bool foundBlock;
AVERT(Pool, pool);
mvff = Pool2MVFF(pool);
AVERT(MVFF, mvff);
AVER(aReturn != NULL);
AVER(size > 0);
AVER(BoolCheck(withReservoirPermit));
UNUSED(info);
size = SizeAlignUp(size, PoolAlignment(pool));
foundBlock = MVFFFindFirstFree(&base, &limit, mvff, size);
if (!foundBlock) {
Seg seg;
res = MVFFAddSeg(&seg, mvff, size, withReservoirPermit);
if (res != ResOK)
return res;
foundBlock = MVFFFindFirstFree(&base, &limit, mvff, size);
/* We know that the found range must intersect the new segment. */
/* In particular, it doesn't necessarily lie entirely within it. */
/* The next three AVERs test for intersection of two intervals. */
AVER(base >= SegBase(seg) || limit <= SegLimit(seg));
AVER(base < SegLimit(seg));
AVER(SegBase(seg) < limit);
/* We also know that the found range is no larger than the segment. */
AVER(SegSize(seg) >= AddrOffset(base, limit));
}
AVER(foundBlock);
AVER(AddrOffset(base, limit) == size);
*aReturn = base;
return ResOK;
}
static void shieldSync(Shield shield, Seg seg)
{
SHIELD_AVERT_CRITICAL(Seg, seg);
if (!SegIsSynced(seg)) {
shieldSetPM(shield, seg, SegSM(seg));
ProtSet(SegBase(seg), SegLimit(seg), SegPM(seg));
}
}
void BufferReassignSeg(Buffer buffer, Seg seg)
{
AVERT(Buffer, buffer);
AVERT(Seg, seg);
AVER(!BufferIsReset(buffer));
AVER(BufferBase(buffer) >= SegBase(seg));
AVER(BufferLimit(buffer) <= SegLimit(seg));
AVER(BufferPool(buffer) == SegPool(seg));
Method(Buffer, buffer, reassignSeg)(buffer, seg);
}
Res PoolAddrObject(Addr *pReturn, Pool pool, Seg seg, Addr addr)
{
AVER(pReturn != NULL);
AVERT(Pool, pool);
AVERT(Seg, seg);
AVER(pool == SegPool(seg));
AVER(SegBase(seg) <= addr);
AVER(addr < SegLimit(seg));
return Method(Pool, pool, addrObject)(pReturn, pool, seg, addr);
}
int init_once(RP rp)
{
switch (done_init) {
case 2: /* fatal error */
return 2;
case 0: /* must init */
Device_Help = rp->pk.init.devhlp;
/* read cmd line params */
read_args(rp->pk.init.args);
done_init = 1;
/* allocate memory */
buf1 = AllocBuf(32l * sizeof(struct tty));
buf2 = AllocBuf(32l * sizeof(struct tty));
if (!buf1 || !buf2)
{
/* fatal */
rp->pk.initexit.cs = 0;
rp->pk.initexit.ds = 0;
done_init = 2;
return 2;
}
DosPutMessage(1, sizeof(version_msg) - 1, version_msg);
DosPutMessage(1, sizeof(once_msg) - 1, once_msg);
if (dbgflag)
{
DosPutMessage(1, sizeof(dbg_msg) - 1, dbg_msg);
int3();
}
/* fall thru */
case 1: /* ok */
#define GETSEL(ptr) ((USHORT)(((ULONG)((void far*)ptr)>>16)&0xffff))
SegLimit(GETSEL(DiscardProc),&rp->pk.initexit.cs);
SegLimit(GETSEL(&DiscardData),&rp->pk.initexit.ds);
}
return 1;
}
static void shieldProtLower(Shield shield, Seg seg, AccessSet mode)
{
/* <design/trace/#fix.noaver> */
SHIELD_AVERT_CRITICAL(Seg, seg);
AVERT_CRITICAL(AccessSet, mode);
if (BS_INTER(SegPM(seg), mode) != AccessSetEMPTY) {
shieldSetPM(shield, seg, BS_DIFF(SegPM(seg), mode));
ProtSet(SegBase(seg), SegLimit(seg), SegPM(seg));
}
}
static void shieldSync(Arena arena, Seg seg)
{
AVERT(Arena, arena);
AVERT(Seg, seg);
if (SegPM(seg) != SegSM(seg)) {
ProtSet(SegBase(seg), SegLimit(seg), SegSM(seg));
SegSetPM(seg, SegSM(seg));
/* inv.prot.shield */
}
}
Res PoolAccess(Pool pool, Seg seg, Addr addr,
AccessSet mode, MutatorFaultContext context)
{
AVERT(Pool, pool);
AVERT(Seg, seg);
AVER(SegBase(seg) <= addr);
AVER(addr < SegLimit(seg));
AVERT(AccessSet, mode);
/* Can't check MutatorFaultContext as there is no check method */
return Method(Pool, pool, access)(pool, seg, addr, mode, context);
}
/* This ensures actual prot mode does not include mode */
static void protLower(Arena arena, Seg seg, AccessSet mode)
{
/* <design/trace/#fix.noaver> */
AVERT_CRITICAL(Arena, arena);
UNUSED(arena);
AVERT_CRITICAL(Seg, seg);
if (SegPM(seg) & mode) {
SegSetPM(seg, SegPM(seg) & ~mode);
ProtSet(SegBase(seg), SegLimit(seg), SegPM(seg));
}
}
static word LookUp( word sdtseg, word seg, word global )
{
dword sdtoff;
dword sdtlim;
dword linear;
word otherseg;
sdtlim = SegLimit( sdtseg );
linear = GetLinear( seg, 0 );
for( sdtoff = 0; sdtoff < sdtlim; sdtoff += 8 ) {
if( sdtoff == ( seg & 0xfff8 ) ) continue;
otherseg = sdtoff + ( global ? 0 : 4 );
if( !WriteOk( otherseg ) ) continue;
if( GetLinear( otherseg, 0 ) != linear ) continue;
_DBG3(("lookup %4.4x", otherseg));
return( otherseg );
}
return( 0 );
}
static void shieldFlushEntries(Shield shield)
{
Addr base = NULL, limit;
AccessSet mode;
Index i;
if (shield->length == 0) {
AVER(shield->queue == NULL);
return;
}
QuickSort((void *)shield->queue, shield->limit,
shieldQueueEntryCompare, UNUSED_POINTER,
&shield->sortStruct);
mode = AccessSetEMPTY;
limit = NULL;
for (i = 0; i < shield->limit; ++i) {
Seg seg = shieldDequeue(shield, i);
if (!SegIsSynced(seg)) {
shieldSetPM(shield, seg, SegSM(seg));
if (SegSM(seg) != mode || SegBase(seg) != limit) {
if (base != NULL) {
AVER(base < limit);
ProtSet(base, limit, mode);
}
base = SegBase(seg);
mode = SegSM(seg);
}
limit = SegLimit(seg);
}
}
if (base != NULL) {
AVER(base < limit);
ProtSet(base, limit, mode);
}
shieldQueueReset(shield);
}
/* MVFFFreeSegs -- Free segments from given range
*
* Given a free range, attempts to find entire segments within
* it, and returns them to the arena, updating total size counter.
*
* This is usually called immediately after MVFFAddToFreeList.
* It is not combined with MVFFAddToFreeList because the latter
* is also called when new segments are added under MVFFAlloc.
*/
static void MVFFFreeSegs(MVFF mvff, Addr base, Addr limit)
{
Seg seg = NULL; /* suppress "may be used uninitialized" */
Arena arena;
Bool b;
Addr segLimit; /* limit of the current segment when iterating */
Addr segBase; /* base of the current segment when iterating */
Res res;
AVERT(MVFF, mvff);
AVER(base < limit);
/* Could profitably AVER that the given range is free, */
/* but the CBS doesn't provide that facility. */
if (AddrOffset(base, limit) < mvff->minSegSize)
return; /* not large enough for entire segments */
arena = PoolArena(MVFF2Pool(mvff));
b = SegOfAddr(&seg, arena, base);
AVER(b);
segBase = SegBase(seg);
segLimit = SegLimit(seg);
while(segLimit <= limit) { /* segment ends in range */
if (segBase >= base) { /* segment starts in range */
RangeStruct range, oldRange;
RangeInit(&range, segBase, segLimit);
res = CBSDelete(&oldRange, CBSOfMVFF(mvff), &range);
if (res == ResOK) {
mvff->free -= RangeSize(&range);
} else if (ResIsAllocFailure(res)) {
/* CBS ran out of memory for splay nodes, which must mean that
* there were fragments on both sides: see
* <design/cbs/#function.cbs.delete.fail>. Handle this by
* deleting the whole of oldRange (which requires no
* allocation) and re-inserting the fragments. */
RangeStruct oldRange2;
res = CBSDelete(&oldRange2, CBSOfMVFF(mvff), &oldRange);
AVER(res == ResOK);
AVER(RangesEqual(&oldRange2, &oldRange));
mvff->free -= RangeSize(&oldRange);
AVER(RangeBase(&oldRange) != segBase);
{
Addr leftBase = RangeBase(&oldRange);
Addr leftLimit = segBase;
res = MVFFAddToFreeList(&leftBase, &leftLimit, mvff);
}
AVER(RangeLimit(&oldRange) != segLimit);
{
Addr rightBase = segLimit;
Addr rightLimit = RangeLimit(&oldRange);
res = MVFFAddToFreeList(&rightBase, &rightLimit, mvff);
}
} else if (res == ResFAIL) {
/* Not found in the CBS: must be found in the Freelist. */
res = FreelistDelete(&oldRange, FreelistOfMVFF(mvff), &range);
AVER(res == ResOK);
mvff->free -= RangeSize(&range);
}
AVER(res == ResOK);
AVER(RangesNest(&oldRange, &range));
/* Can't free the segment earlier, because if it was on the
* Freelist rather than the CBS then it likely contains data
* that needs to be read in order to update the Freelist. */
SegFree(seg);
mvff->total -= RangeSize(&range);
}
/* Avoid calling SegNext if the next segment would fail */
/* the loop test, mainly because there might not be a */
/* next segment. */
if (segLimit == limit) /* segment ends at end of range */
break;
b = SegFindAboveAddr(&seg, arena, segBase);
AVER(b);
segBase = SegBase(seg);
segLimit = SegLimit(seg);
}
return;
}
/* AMSTBufferFill -- the pool class buffer fill method
*
* Calls next method - but possibly splits or merges the chosen
* segment.
*
* .merge: A merge is performed when the next method returns the
* entire segment, this segment had previously been split from the
* segment below, and the segment below is appropriately similar
* (i.e. not already attached to a buffer and similarly coloured)
*
* .split: If we're not merging, a split is performed if the next method
* returns the entire segment, and yet lower half of the segment would
* meet the request.
*/
static Res AMSTBufferFill(Addr *baseReturn, Addr *limitReturn,
Pool pool, Buffer buffer, Size size)
{
Addr base, limit;
Arena arena;
AMS ams;
AMST amst;
Bool b;
Seg seg;
AMSTSeg amstseg;
Res res;
AVERT(Pool, pool);
AVER(baseReturn != NULL);
AVER(limitReturn != NULL);
/* other parameters are checked by next method */
arena = PoolArena(pool);
ams = PoolAMS(pool);
amst = PoolAMST(pool);
/* call next method */
res = NextMethod(Pool, AMSTPool, bufferFill)(&base, &limit, pool, buffer, size);
if (res != ResOK)
return res;
b = SegOfAddr(&seg, arena, base);
AVER(b);
amstseg = Seg2AMSTSeg(seg);
if (SegLimit(seg) == limit && SegBase(seg) == base) {
if (amstseg->prev != NULL) {
Seg segLo = AMSTSeg2Seg(amstseg->prev);
if (!SegHasBuffer(segLo) &&
SegGrey(segLo) == SegGrey(seg) &&
SegWhite(segLo) == SegWhite(seg)) {
/* .merge */
Seg mergedSeg;
Res mres;
AMSUnallocateRange(ams, seg, base, limit);
mres = SegMerge(&mergedSeg, segLo, seg);
if (ResOK == mres) { /* successful merge */
AMSAllocateRange(ams, mergedSeg, base, limit);
/* leave range as-is */
} else { /* failed to merge */
AVER(amst->failSegs); /* deliberate fails only */
AMSAllocateRange(ams, seg, base, limit);
}
}
} else {
Size half = SegSize(seg) / 2;
if (half >= size && SizeIsArenaGrains(half, arena)) {
/* .split */
Addr mid = AddrAdd(base, half);
Seg segLo, segHi;
Res sres;
AMSUnallocateRange(ams, seg, mid, limit);
sres = SegSplit(&segLo, &segHi, seg, mid);
if (ResOK == sres) { /* successful split */
limit = mid; /* range is lower segment */
} else { /* failed to split */
AVER(amst->failSegs); /* deliberate fails only */
AMSAllocateRange(ams, seg, mid, limit);
}
}
}
}
*baseReturn = base;
*limitReturn = limit;
return ResOK;
}