Changeset c520034 in mainline for kernel/arch/amd64/src/mm/page.c

Timestamp:

2011-12-31T18:19:35Z (12 years ago)

Author:

Jakub Jermar <jakub@…>

Branches:

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

Children:

295f658, 77c2b02, 96cd5b4

Parents:

852052d (diff), 22f0561 (diff)
Note: this is a merge changeset, the changes displayed below correspond to the merge itself.
Use the (diff) links above to see all the changes relative to each parent.

Message:

Support for kernel non-identity mappings, phase I.

• identity/non-identity kernel memory split on all architectures
• low/high physical memory split on all architectures
• frame allocator understands low/high memory
• high physical memory currently unused (Phase II)
• more compact frame_t
• zone conf frames, pte_t, kernel stacks allocated from low memory
• lockless TLB-miss handlers everywhere (newly sparc64, ia64)
• preallocate PTL1 page tables for non-identity and prevent their deallocation
• hw_map() unification
• new resource allocator used for allocating kernel virtual addresses

Breakage:

• sparc64/sun4v creates too large kernel identity; not fixed because of lack of testing hw
• ppc32's tlb_refill() seems wrong as it creates too large kernel identity, but appears unused and the architecture works normally

Not implemented yet (phase II):

• allow high memory to be used for common kernel allocations

File:

• kernel/arch/amd64/src/mm/page.c (modified) (2 diffs)

kernel/arch/amd64/src/mm/page.c

@@ -46 +46 @@
 #include <panic.h>
 #include <align.h>
+#include <macros.h>
 
 void page_arch_init(void)
 {
-        if (config.cpu_active == 1) {
-                uintptr_t cur;
-                unsigned int identity_flags =
-                    PAGE_CACHEABLE | PAGE_EXEC | PAGE_GLOBAL | PAGE_WRITE;
+        if (config.cpu_active > 1) {
+                write_cr3((uintptr_t) AS_KERNEL->genarch.page_table);
+                return;
+        }
+
+        uintptr_t cur;
+        unsigned int identity_flags =
+            PAGE_CACHEABLE | PAGE_EXEC | PAGE_GLOBAL | PAGE_WRITE;
                 
-                page_mapping_operations = &pt_mapping_operations;
+        page_mapping_operations = &pt_mapping_operations;
                 
-                page_table_lock(AS_KERNEL, true);
+        page_table_lock(AS_KERNEL, true);
                 
-                /*
-                 * PA2KA(identity) mapping for all frames.
-                 */
-                for (cur = 0; cur < last_frame; cur += FRAME_SIZE)
-                        page_mapping_insert(AS_KERNEL, PA2KA(cur), cur, identity_flags);
+        /*
+         * PA2KA(identity) mapping for all low-memory frames.
+         */
+        for (cur = 0; cur < min(config.identity_size, config.physmem_end);
+            cur += FRAME_SIZE)
+                page_mapping_insert(AS_KERNEL, PA2KA(cur), cur, identity_flags);
                 
-                page_table_unlock(AS_KERNEL, true);
+        page_table_unlock(AS_KERNEL, true);
                 
-                exc_register(14, "page_fault", true, (iroutine_t) page_fault);
-                write_cr3((uintptr_t) AS_KERNEL->genarch.page_table);
-        } else
-                write_cr3((uintptr_t) AS_KERNEL->genarch.page_table);
+        exc_register(14, "page_fault", true, (iroutine_t) page_fault);
+        write_cr3((uintptr_t) AS_KERNEL->genarch.page_table);
 }
 
@@ -94 +98 @@
 }
 
-uintptr_t hw_map(uintptr_t physaddr, size_t size)
-{
-        if (last_frame + ALIGN_UP(size, PAGE_SIZE) > KA2PA(KERNEL_ADDRESS_SPACE_END_ARCH))
-                panic("Unable to map physical memory %p (%zu bytes).",
-                    (void *) physaddr, size);
-        
-        uintptr_t virtaddr = PA2KA(last_frame);
-        pfn_t i;
-        
-        page_table_lock(AS_KERNEL, true);
-        
-        for (i = 0; i < ADDR2PFN(ALIGN_UP(size, PAGE_SIZE)); i++)
-                page_mapping_insert(AS_KERNEL, virtaddr + PFN2ADDR(i), physaddr + PFN2ADDR(i), PAGE_NOT_CACHEABLE | PAGE_WRITE);
-        
-        page_table_unlock(AS_KERNEL, true);
-        
-        last_frame = ALIGN_UP(last_frame + size, FRAME_SIZE);
-        
-        return virtaddr;
-}
-
 /** @}
  */