Changeset 1cc2974 in mainline for kernel/generic/src/lib/elf.c

Timestamp:

2008-05-26T18:56:34Z (17 years ago)

Author:

Jakub Jermar <jakub@…>

Branches:

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

Children:

5a55ae6

Parents:

fa832eb

Message:

Improve linking and loading of boot ELF images.
(Contributed by Jiri Svoboda)

File:

• kernel/generic/src/lib/elf.c (modified) (3 diffs)

kernel/generic/src/lib/elf.c

@@ -101 +101 @@
                 return EE_UNSUPPORTED;
 
+        /* Check if the ELF image starts on a page boundary */
+        if (ALIGN_UP((uintptr_t)header, PAGE_SIZE) != (uintptr_t)header)
+                return EE_UNSUPPORTED;
+
         /* Walk through all segment headers and process them. */
         for (i = 0; i < header->e_phnum; i++) {
@@ -183 +187 @@
         int flags = 0;
         mem_backend_data_t backend_data;
+        uintptr_t base;
+        size_t mem_sz;
         
         backend_data.elf = elf;
@@ -202 +208 @@
         flags |= AS_AREA_CACHEABLE;
 
-        /*
-         * Check if the virtual address starts on page boundary.
+        /* 
+         * Align vaddr down, inserting a little "gap" at the beginning.
+         * Adjust area size, so that its end remains in place.
          */
-        if (ALIGN_UP(entry->p_vaddr, PAGE_SIZE) != entry->p_vaddr)
-                return EE_UNSUPPORTED;
-
-        a = as_area_create(as, flags, entry->p_memsz, entry->p_vaddr,
+        base = ALIGN_DOWN(entry->p_vaddr, PAGE_SIZE);
+        mem_sz = entry->p_memsz + (entry->p_vaddr - base);
+
+        a = as_area_create(as, flags, mem_sz, base,
             AS_AREA_ATTR_NONE, &elf_backend, &backend_data);
         if (!a)