Revert "Add subroutines to add/remove blocks from the expiry chain"

This reverts commit 8920cf3559c034c947c2dd63892c9dd25453d245.

The functionality needs some more polish, but we don't actually need
it at the moment.

diff --git a/cache.inc b/cache.inc
index 1f514e2..0d9d453 100644 (file)
--- a/cache.inc
+++ b/cache.inc
@@ -13,9 +13,9 @@
                section .text
 
                struc cptr
-.sector:       resd 1          ; Sector number
-.prev:         resw 1          ; LRU pointer to previous (less recent)
-.next:         resw 1          ; LRU pointer to next (more recent)
+.sector:       resd 1                          ; Sector number
+.prev:         resw 1                          ; LRU pointer to previous (less recent)
+.next:         resw 1                          ; LRU pointer to next (more recent)
                endstruc
 cptr_size_lg2  equ 3
 
@@ -39,52 +39,6 @@ initcache:
                ret
 
 ;
-; cache_remove_lru:
-;      Remove a cache block from the expiry list.  Can be used to
-;      lock down a cache block for future use.
-;
-;      SI = cache block offset (any offset inside the block is OK)
-;      Assumes CS == DS
-;
-cache_remove_lru:
-               pusha
-
-               ; Get metadata pointer
-               shr si,SECTOR_SHIFT-cptr_size_lg2
-               add si,CachePtrs+cptr_size
-
-               mov bx,[si+cptr.prev]
-               mov di,[si+cptr.next]
-               mov [bx+cptr.next],di
-               mov [di+cptr.prev],bx
-
-               popa
-               ret
-
-;
-; cache_add_lru:
-;      Add back a cache block to the expiry chain that was removed.
-;
-;      SI = cache block offset (any offset inside the block is OK)
-;      Assumes CS == DS
-;
-cache_add_lru:
-               pusha
-
-               ; Get metadata pointer
-               shr si,SECTOR_SHIFT-cptr_size_lg2
-               add si,CachePtrs+cptr_size
-
-               mov bx,[CachePtrs+cptr.prev]
-               mov [si+cptr.prev],bx
-               mov [bx+cptr.next],si
-               mov [CachePtrs+cptr.prev],si
-               mov word [si+cptr.next],CachePtrs
-
-               popa
-               ret
-
-;
 ; getcachesector: Check for a particular sector (EAX) in the sector cache,
 ;                and if it is already there, return a pointer in GS:SI
 ;                otherwise load it and return said pointer.
@@ -128,14 +82,21 @@ getcachesector:
                ; Update LRU, then compute buffer address
                TRACER 'H'
 
-               sub si,CachePtrs+cptr_size
-               shl si,SECTOR_SHIFT-cptr_size_lg2       ; Buffer address
-
                ; Remove from current position in the list
-               call cache_remove_lru
+               mov bx,[si+cptr.prev]
+               mov di,[si+cptr.next]
+               mov [bx+cptr.next],di
+               mov [di+cptr.prev],bx
 
                ; Add to just before head node
-               call cache_add_lru
+               mov bx,[CachePtrs+cptr.prev]
+               mov [si+cptr.prev],bx
+               mov [bx+cptr.next],si
+               mov [CachePtrs+cptr.prev],si
+               mov word [si+cptr.next],CachePtrs
+
+               sub si,CachePtrs+cptr_size
+               shl si,SECTOR_SHIFT-cptr_size_lg2       ; Buffer address
 
                pop di
                pop bx