Changeset 03cdd2b in mainline

Timestamp:

2012-01-31T22:44:35Z (12 years ago)

Author:

Jakub Jermar <jakub@…>

Branches:

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

Children:

b860f9e

Parents:

bf3dd35

Message:

Add km_unmap() and km_unmap_aligned().

Location:

kernel/generic

Files:

• include/mm/km.h (modified) (1 diff)
• src/mm/km.c (modified) (2 diffs)

kernel/generic/include/mm/km.h

@@ -50 +50 @@
 
 extern uintptr_t km_map(uintptr_t, size_t, unsigned int);
+extern void km_unmap(uintptr_t, size_t);
 
 extern uintptr_t km_temporary_page_get(uintptr_t *, frame_flags_t);

kernel/generic/src/mm/km.c

@@ -128 +128 @@
 {
         uintptr_t vaddr;
-        size_t asize;
         size_t align;
         uintptr_t offs;
 
-        asize = ALIGN_UP(size, PAGE_SIZE);
+        ASSERT(ALIGN_DOWN(paddr, FRAME_SIZE) == paddr);
+        ASSERT(ALIGN_UP(size, FRAME_SIZE) == size);
+
         align = ispwr2(size) ? size : (1U << (fnzb(size) + 1));
-        vaddr = km_page_alloc(asize, max(PAGE_SIZE, align));
+        vaddr = km_page_alloc(size, max(PAGE_SIZE, align));
 
         page_table_lock(AS_KERNEL, true);
-        for (offs = 0; offs < asize; offs += PAGE_SIZE) {
+        for (offs = 0; offs < size; offs += PAGE_SIZE) {
                 page_mapping_insert(AS_KERNEL, vaddr + offs, paddr + offs,
                     flags);
@@ -146 +147 @@
 }
 
+static void km_unmap_aligned(uintptr_t vaddr, size_t size)
+{
+        uintptr_t offs;
+        ipl_t ipl;
+
+        ASSERT(ALIGN_DOWN(vaddr, PAGE_SIZE) == vaddr);
+        ASSERT(ALIGN_UP(size, PAGE_SIZE) == size);
+
+        page_table_lock(AS_KERNEL, true);
+
+        ipl = tlb_shootdown_start(TLB_INVL_ASID, ASID_KERNEL, 0, 0);
+
+        for (offs = 0; offs < size; offs += PAGE_SIZE)
+                page_mapping_remove(AS_KERNEL, vaddr + offs);
+
+        tlb_invalidate_asid(ASID_KERNEL);
+
+        as_invalidate_translation_cache(AS_KERNEL, 0, -1);
+        tlb_shootdown_finalize(ipl);
+        page_table_unlock(AS_KERNEL, true);
+
+        km_page_free(vaddr, size);
+}
+
+/** Map a piece of physical address space into the virtual address space.
+ *
+ * @param paddr         Physical address to be mapped. May be unaligned.
+ * @param size          Size of area starting at paddr to be mapped.
+ * @param flags         Protection flags to be used for the mapping.
+ *
+ * @return New virtual address mapped to paddr.
+ */
 uintptr_t km_map(uintptr_t paddr, size_t size, unsigned int flags)
 {
-        size_t offs = paddr - ALIGN_DOWN(paddr, FRAME_SIZE); 
         uintptr_t page;
-
-        page = km_map_aligned(ALIGN_DOWN(paddr, FRAME_SIZE), size + offs,
-            flags);
+        size_t offs; 
+
+        offs = paddr - ALIGN_DOWN(paddr, FRAME_SIZE); 
+        page = km_map_aligned(ALIGN_DOWN(paddr, FRAME_SIZE),
+            ALIGN_UP(size + offs, FRAME_SIZE), flags);
+
         return page + offs;
 }
 
-/** Unmap kernen non-identity page.
+/** Unmap a piece of virtual address space.
+ *
+ * @param vaddr         Virtual address to be unmapped. May be unaligned, but
+ *                      it must a value previously returned by km_map().
+ * @param size          Size of area starting at vaddr to be unmapped.
+ */
+void km_unmap(uintptr_t vaddr, size_t size)
+{
+        size_t offs; 
+
+        offs = vaddr - ALIGN_DOWN(vaddr, PAGE_SIZE); 
+        km_unmap_aligned(ALIGN_DOWN(vaddr, PAGE_SIZE),
+            ALIGN_UP(size + offs, PAGE_SIZE));
+}
+
+/** Unmap kernel non-identity page.
  *
  * @param[in] page      Non-identity page to be unmapped.