Changeset 2057572 in mainline for kernel/generic/src/ddi/ddi.c

Timestamp:

2007-03-27T23:40:25Z (18 years ago)

Author:

Jakub Jermar <jakub@…>

Branches:

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

Children:

399ece9

Parents:

8d37a06

Message:

The Ultimate Solution To Illegal Virtual Aliases.
It is better to avoid them completely than to fight them.
Switch the sparc64 port to 16K pages. The TLBs and TSBs
continue to operate with 8K pages only. Page tables and
other generic parts operate with 16K pages.

Because the MMU doesn't support 16K directly, each 16K
page is emulated by a pair of 8K pages. With 16K pages,
illegal aliases cannot be created in 16K D-cache.

File:

• kernel/generic/src/ddi/ddi.c (modified) (2 diffs)

kernel/generic/src/ddi/ddi.c

@@ -100 +100 @@
  *      syscall, ENOENT if there is no task matching the specified ID or the
  *      physical address space is not enabled for mapping and ENOMEM if there
- *      was a problem in creating address space area. ENOTSUP is returned when
- *      an attempt to create an illegal address alias is detected.
+ *      was a problem in creating address space area.
  */
 static int ddi_physmem_map(uintptr_t pf, uintptr_t vp, count_t pages, int flags)
@@ -140 +139 @@
                 return ENOENT;
         }
-
-#ifdef CONFIG_VIRT_IDX_DCACHE
-        if (PAGE_COLOR(parea->vbase) != PAGE_COLOR(vp)) {
-                /*
-                 * Refuse to create an illegal address alias.
-                 */
-                spinlock_unlock(&parea_lock);
-                interrupts_restore(ipl);
-                return ENOTSUP;
-        }
-#endif /* CONFIG_VIRT_IDX_DCACHE */
-
         spinlock_unlock(&parea_lock);