sys/uvm/uvm_amap.c

109  * amap_chunk_get: lookup a chunk for slot. if create is non-zero,
110  * the chunk is created if it does not yet exist.
112  * => returns the chunk on success or NULL on error
120 	struct vm_amap_chunk *chunk, *newchunk, *pchunk = NULL;
125 	for (chunk = amap->am_buckets[bucket]; chunk != NULL;
126 	    chunk = TAILQ_NEXT(chunk, ac_list)) {
127 		if (UVM_AMAP_BUCKET(amap, chunk->ac_baseslot) != bucket)
129 		if (chunk->ac_baseslot == baseslot)
130 			return chunk;
131 		pchunk = chunk;
160 amap_chunk_free(struct vm_amap *amap, struct vm_amap_chunk *chunk)
162 	int bucket = UVM_AMAP_BUCKET(amap, chunk->ac_baseslot);
168 	nchunk = TAILQ_NEXT(chunk, ac_list);
169 	TAILQ_REMOVE(&amap->am_chunks, chunk, ac_list);
170 	if (amap->am_buckets[bucket] == chunk) {
178 	pool_put(&uvm_amap_chunk_pool, chunk);
197  * the chunk reference count plus one is stored in that chunk's slot.
200  * greater than one.]   the second slot of the chunk contains the length
201  * of the chunk.   here is an example:
209  * chunk.    note that the "plus one" part is needed because a reference
225 	if (ppref[offset] > 0) {		/* chunk size must be 1 */
291 	struct vm_amap_chunk *chunk, *tmp;
313 		 * of lookups we would have if we could chunk the amap. The
382 			chunk = pool_get(&uvm_amap_chunk_pool,
384 			if (chunk == NULL)
387 			amap->am_buckets[i] = chunk;
389 			chunk->ac_baseslot = i * UVM_AMAP_CHUNK;
390 			chunk->ac_nslot = n;
391 			TAILQ_INSERT_TAIL(&amap->am_chunks, chunk, ac_list);
399 	TAILQ_FOREACH_SAFE(chunk, &amap->am_chunks, ac_list, tmp)
400 		pool_put(&uvm_amap_chunk_pool, chunk);
447 	struct vm_amap_chunk *chunk, *tmp;
465 		TAILQ_FOREACH_SAFE(chunk, &amap->am_chunks, ac_list, tmp)
466 		    pool_put(&uvm_amap_chunk_pool, chunk);
484 	struct vm_amap_chunk *chunk;
499 	AMAP_CHUNK_FOREACH(chunk, amap) {
500 		int i, refs, map = chunk->ac_usedmap;
505 			anon = chunk->ac_anon[slot];
537  * => if canchunk is true, then we may clip the entry into a chunk
552 	struct vm_amap_chunk *chunk = NULL, *srcchunk = NULL;
563 		 * chunk.  We align startva/endva to chunk-sized
566 		 * If we cannot chunk the amap, allocate it in a way
659 		chunk = amap_chunk_get(amap, lcv, 1, PR_NOWAIT);
660 		if (chunk == NULL) {
669 			chunk->ac_anon[i] = anon = srcchunk->ac_anon[j];
675 			chunk->ac_usedmap |= (1 << i);
744 	struct vm_amap_chunk *chunk;
753 	AMAP_CHUNK_FOREACH(chunk, amap) {
754 		int i, map = chunk->ac_usedmap;
759 			anon = chunk->ac_anon[slot];
817 			chunk->ac_anon[slot] = nanon;
931 		 * the ppref array; that is, there is no previous chunk.
967 amap_wiperange_chunk(struct vm_amap *amap, struct vm_amap_chunk *chunk,
977 	map = chunk->ac_usedmap;
978 	if (startbase == chunk->ac_baseslot)
980 	if (endbase == chunk->ac_baseslot)
988 		chunk->ac_usedmap ^= 1 << curslot;
989 		anon = chunk->ac_anon[curslot];
993 		chunk->ac_anon[curslot] = NULL;
1020 	struct vm_amap_chunk *chunk, *nchunk;
1034 		TAILQ_FOREACH_SAFE(chunk, &amap->am_chunks, ac_list, nchunk) {
1035 			if (chunk->ac_baseslot + chunk->ac_nslot <= slotoff)
1037 			if (chunk->ac_baseslot >= slotoff + slots)
1040 			amap_wiperange_chunk(amap, chunk, slotoff, slots);
1041 			if (chunk->ac_usedmap == 0)
1042 				amap_chunk_free(amap, chunk);
1046 			for (chunk = amap->am_buckets[bucket]; chunk != NULL;
1047 			    chunk = nchunk) {
1048 				nchunk = TAILQ_NEXT(chunk, ac_list);
1050 				if (UVM_AMAP_BUCKET(amap, chunk->ac_baseslot) !=
1053 				if (chunk->ac_baseslot + chunk->ac_nslot <=
1056 				if (chunk->ac_baseslot >= slotoff + slots)
1059 				amap_wiperange_chunk(amap, chunk, slotoff,
1061 				if (chunk->ac_usedmap == 0)
1062 					amap_chunk_free(amap, chunk);
1089 		struct vm_amap_chunk *chunk;
1102 		AMAP_CHUNK_FOREACH(chunk, am) {
1103 			map = chunk->ac_usedmap;
1111 				anon = chunk->ac_anon[slot];
1156 	struct vm_amap_chunk *chunk;
1162 	chunk = amap_chunk_get(amap, slot, 0, PR_NOWAIT);
1163 	if (chunk == NULL)
1166 	return chunk->ac_anon[UVM_AMAP_SLOTIDX(slot)];
1181 	struct vm_amap_chunk *chunk = NULL;
1193 		chunk = amap_chunk_get(amap, lcv, 0, PR_NOWAIT);
1194 		if (chunk == NULL)
1198 			    &chunk->ac_anon[UVM_AMAP_SLOTIDX(lcv)],
1213 	struct vm_amap_chunk *chunk;
1219 	chunk = amap_chunk_get(amap, slot, 1, PR_WAITOK);
1220 	KASSERT(chunk != NULL);
1235 	struct vm_amap_chunk *chunk;
1241 	chunk = amap_chunk_get(amap, slot, 1, PR_NOWAIT);
1242 	if (chunk == NULL)
1247 		struct vm_anon *oanon  = chunk->ac_anon[slot];
1257 		if (chunk->ac_anon[slot] != NULL)
1260 		chunk->ac_usedmap |= 1 << slot;
1263 	chunk->ac_anon[slot] = anon;
1277 	struct vm_amap_chunk *chunk;
1285 	chunk = amap_chunk_get(amap, slot, 0, PR_NOWAIT);
1286 	KASSERT(chunk != NULL);
1289 	KASSERT(chunk->ac_anon[slot] != NULL);
1291 	chunk->ac_anon[slot] = NULL;
1292 	chunk->ac_usedmap &= ~(1 << slot);
1295 	if (chunk->ac_usedmap == 0)
1296 		amap_chunk_free(amap, chunk);