Changeset 20d50a1 in mainline for arch/mips32/src/mm/tlb.c

Timestamp:

2006-01-13T13:02:45Z (19 years ago)

Author:

Jakub Jermar <jakub@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

f9425006

Parents:

0369911

Message:

Memory management work.

• vm.* → as.* (as like address space is, imho, more fitting)
• Don't do TLB shootdown on vm_install(). Some architectures only need to call tlb_invalidate_asid().
• Don't allocate all frames for as_area in as_area_create(), but let them be allocated on-demand by as_page_fault().
• Add high-level page fault handler as_page_fault().
• Add as_area_load_mapping().

File:

• arch/mips32/src/mm/tlb.c (modified) (10 diffs)

arch/mips32/src/mm/tlb.c

@@ -31 +31 @@
 #include <mm/tlb.h>
 #include <mm/page.h>
-#include <mm/vm.h>
+#include <mm/as.h>
 #include <arch/cp0.h>
 #include <panic.h>
@@ -93 +93 @@
         badvaddr = cp0_badvaddr_read();
 
-        spinlock_lock(&VM->lock);               
+        spinlock_lock(&AS->lock);               
 
         pte = find_mapping_and_check(badvaddr);
@@ -104 +104 @@
         pte->a = 1;
 
-        prepare_entry_hi(&hi, VM->asid, badvaddr);
+        prepare_entry_hi(&hi, AS->asid, badvaddr);
         prepare_entry_lo(&lo, pte->lo.g, pte->lo.v, pte->lo.d, pte->lo.c, pte->lo.pfn);
 
@@ -122 +122 @@
         tlbwr();
 
-        spinlock_unlock(&VM->lock);
+        spinlock_unlock(&AS->lock);
         return;
         
 fail:
-        spinlock_unlock(&VM->lock);
+        spinlock_unlock(&AS->lock);
         tlb_refill_fail(pstate);
 }
@@ -155 +155 @@
         index.value = cp0_index_read();
         
-        spinlock_lock(&VM->lock);       
+        spinlock_lock(&AS->lock);       
         
         /*
@@ -191 +191 @@
         tlbwi();
 
-        spinlock_unlock(&VM->lock);     
+        spinlock_unlock(&AS->lock);     
         return;
         
 fail:
-        spinlock_unlock(&VM->lock);
+        spinlock_unlock(&AS->lock);
         tlb_invalid_fail(pstate);
 }
@@ -224 +224 @@
         index.value = cp0_index_read();
         
-        spinlock_lock(&VM->lock);       
+        spinlock_lock(&AS->lock);       
         
         /*
@@ -267 +267 @@
         tlbwi();
 
-        spinlock_unlock(&VM->lock);     
+        spinlock_unlock(&AS->lock);     
         return;
         
 fail:
-        spinlock_unlock(&VM->lock);
+        spinlock_unlock(&AS->lock);
         tlb_modified_fail(pstate);
 }
@@ -313 +313 @@
  *
  * Try to find PTE for faulting address.
- * The VM->lock must be held on entry to this function.
+ * The AS->lock must be held on entry to this function.
  *
  * @param badvaddr Faulting virtual address.
@@ -329 +329 @@
          * Handler cannot succeed if the ASIDs don't match.
          */
-        if (hi.asid != VM->asid) {
-                printf("EntryHi.asid=%d, VM->asid=%d\n", hi.asid, VM->asid);
+        if (hi.asid != AS->asid) {
+                printf("EntryHi.asid=%d, AS->asid=%d\n", hi.asid, AS->asid);
                 return NULL;
         }
-        
+
+        /*
+         * Check if the mapping exists in page tables.
+         */     
+        pte = page_mapping_find(badvaddr, AS->asid, 0);
+        if (pte && pte->lo.v) {
+                /*
+                 * Mapping found in page tables.
+                 * Immediately succeed.
+                 */
+                return pte;
+        } else {
+                /*
+                 * Mapping not found in page tables.
+                 * Resort to higher-level page fault handler.
+                 */
+                if (as_page_fault(badvaddr)) {
+                        /*
+                         * The higher-level page fault handler succeeded,
+                         * The mapping ought to be in place.
+                         */
+                        pte = page_mapping_find(badvaddr, AS->asid, 0);
+                        ASSERT(pte && pte->lo.v);
+                        return pte;
+                }
+        }
+
         /*
          * Handler cannot succeed if badvaddr has no mapping.
          */
-        pte = page_mapping_find(badvaddr, VM->asid, 0);
         if (!pte) {
                 printf("No such mapping.\n");