Initial (manual) import

2017-01-22 20:26:44 +01:00
1 parent f39611c506
commit 895fe109de
@@ -0,0 +1,145 @@
+U0 DskCacheInit(I64 size_in_U8s)
+{
+  CCacheBlk *tmpc;
+  I64 i,cnt;
+
+  while (LBts(&sys_semas[SEMA_DSK_CACHE],0))
+    Yield;
+  Free(blkdev.cache_ctrl);
+  Free(blkdev.cache_base);
+  Free(blkdev.cache_hash_table);
+  if (size_in_U8s<0x2000) {
+    blkdev.cache_ctrl=NULL;
+    blkdev.cache_base=NULL;
+    blkdev.cache_hash_table=NULL;
+  } else {
+    blkdev.cache_ctrl=ACAlloc(offset(CCacheBlk.body));
+    blkdev.cache_base=AMAlloc(size_in_U8s);
+    QueInit(blkdev.cache_ctrl);
+
+    cnt=MSize(blkdev.cache_base)/sizeof(CCacheBlk);
+    blkdev.cache_size=cnt*BLK_SIZE;
+    for (i=0;i<cnt;i++) {
+      tmpc=blkdev.cache_base+i;
+      QueIns(tmpc,blkdev.cache_ctrl->last_lru);
+      tmpc->next_hash=tmpc->last_hash=tmpc;
+      tmpc->dv=NULL;
+      tmpc->blk=0;
+    }
+
+    blkdev.cache_hash_table=AMAlloc(DSK_CACHE_HASH_SIZE*sizeof(U8 *)*2);
+    for (i=0;i<DSK_CACHE_HASH_SIZE;i++) {
+      tmpc=blkdev.cache_hash_table(U8 *)+i*sizeof(U8 *)*2
+	    -offset(CCacheBlk.next_hash);
+      tmpc->next_hash=tmpc->last_hash=tmpc;
+    }
+  }
+  LBtr(&sys_semas[SEMA_DSK_CACHE],0);
+}
+
+I64 DskCacheHash(I64 blk)
+{
+  I64 i=blk & (DSK_CACHE_HASH_SIZE-1);
+  return blkdev.cache_hash_table(U8 *)+i<<4-offset(CCacheBlk.next_hash);
+}
+
+U0 DskCacheQueRem(CCacheBlk *tmpc)
+{
+  QueRem(tmpc);
+  tmpc->next_hash->last_hash=tmpc->last_hash;
+  tmpc->last_hash->next_hash=tmpc->next_hash;
+}
+
+U0 DskCacheQueIns(CCacheBlk *tmpc)
+{
+  CCacheBlk *tmp_n,*tmp_l;
+  QueIns(tmpc,blkdev.cache_ctrl->last_lru);
+  tmp_l=DskCacheHash(tmpc->blk);
+  tmp_n=tmp_l->next_hash;
+  tmpc->last_hash=tmp_l;
+  tmpc->next_hash=tmp_n;
+  tmp_l->next_hash=tmp_n->last_hash=tmpc;
+}
+
+CCacheBlk *DskCacheFind(CDrv *dv,I64 blk)
+{
+  CCacheBlk *tmpc,*tmpc1=DskCacheHash(blk);
+  tmpc=tmpc1->next_hash;
+  while (tmpc!=tmpc1) {
+    if (tmpc->dv==dv && tmpc->blk==blk)
+      return tmpc;
+    tmpc=tmpc->next_hash;
+  }
+  return NULL;
+}
+
+U0 DskCacheAdd(CDrv *dv,U8 *buf, I64 blk, I64 cnt)
+{
+  CCacheBlk *tmpc;
+  if (blkdev.cache_base) {
+    while (LBts(&sys_semas[SEMA_DSK_CACHE],0))
+      Yield;
+    while (cnt-->0) {
+      if (!(tmpc=DskCacheFind(dv,blk)))
+	tmpc=blkdev.cache_ctrl->next_lru;
+      DskCacheQueRem(tmpc);
+      MemCpy(&tmpc->body,buf,BLK_SIZE);
+      tmpc->dv=dv;
+      tmpc->blk=blk;
+      DskCacheQueIns(tmpc);
+      blk++;
+      buf+=BLK_SIZE;
+    }
+    LBtr(&sys_semas[SEMA_DSK_CACHE],0);
+  }
+}
+
+U0 DskCacheInvalidate2(CDrv *dv)
+{
+  CCacheBlk *tmpc,*tmpc1;
+  if (blkdev.cache_base) {
+    while (LBts(&sys_semas[SEMA_DSK_CACHE],0))
+      Yield;
+    tmpc=blkdev.cache_ctrl->last_lru;
+    while (tmpc!=blkdev.cache_ctrl) {
+      tmpc1=tmpc->last_lru;
+      if (tmpc->dv==dv) {
+	DskCacheQueRem(tmpc);
+	tmpc->dv=NULL;
+	tmpc->blk=0;
+	tmpc->next_hash=tmpc->last_hash=tmpc;
+	QueIns(tmpc,blkdev.cache_ctrl->last_lru);
+      }
+      tmpc=tmpc1;
+    }
+    LBtr(&sys_semas[SEMA_DSK_CACHE],0);
+  }
+}
+
+U0 RCache(CDrv *dv,U8 **_buf, I64 *_blk, I64 *_cnt)
+{
+  CCacheBlk *tmpc;
+  if (blkdev.cache_base) {
+    while (LBts(&sys_semas[SEMA_DSK_CACHE],0))
+      Yield;
+//fetch leading blks from cache
+    while (*_cnt>0) {
+      if (tmpc=DskCacheFind(dv,*_blk)) {
+	MemCpy(*_buf,&tmpc->body,BLK_SIZE);
+	*_cnt-=1;
+	*_buf+=BLK_SIZE;
+	*_blk+=1;
+      } else
+	break;
+    }
+//fetch trailing blks from cache
+    while (*_cnt>0) {
+      if (tmpc=DskCacheFind(dv,*_blk+*_cnt-1)) {
+	MemCpy(*_buf+(*_cnt-1)<<BLK_SIZE_BITS,&tmpc->body,BLK_SIZE);
+	*_cnt-=1;
+      } else
+	break;
+    }
+    LBtr(&sys_semas[SEMA_DSK_CACHE],0);
+  }
+}