Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
diff --git a/arch/cris/mm/tlb.c b/arch/cris/mm/tlb.c
new file mode 100644
index 0000000..23eca5a
--- /dev/null
+++ b/arch/cris/mm/tlb.c
@@ -0,0 +1,126 @@
+/*
+ * linux/arch/cris/mm/tlb.c
+ *
+ * Copyright (C) 2000, 2001 Axis Communications AB
+ *
+ * Authors: Bjorn Wesen (bjornw@axis.com)
+ *
+ */
+
+#include <linux/init.h>
+#include <asm/tlb.h>
+
+#define D(x)
+
+/* The TLB can host up to 64 different mm contexts at the same time.
+ * The running context is R_MMU_CONTEXT, and each TLB entry contains a
+ * page_id that has to match to give a hit. In page_id_map, we keep track
+ * of which mm's we have assigned which page_id's, so that we know when
+ * to invalidate TLB entries.
+ *
+ * The last page_id is never running - it is used as an invalid page_id
+ * so we can make TLB entries that will never match.
+ *
+ * Notice that we need to make the flushes atomic, otherwise an interrupt
+ * handler that uses vmalloced memory might cause a TLB load in the middle
+ * of a flush causing.
+ */
+
+struct mm_struct *page_id_map[NUM_PAGEID];
+static int map_replace_ptr = 1; /* which page_id_map entry to replace next */
+
+/*
+ * Initialize the context related info for a new mm_struct
+ * instance.
+ */
+
+int
+init_new_context(struct task_struct *tsk, struct mm_struct *mm)
+{
+ mm->context = NO_CONTEXT;
+ return 0;
+}
+
+/* the following functions are similar to those used in the PPC port */
+
+static inline void
+alloc_context(struct mm_struct *mm)
+{
+ struct mm_struct *old_mm;
+
+ D(printk("tlb: alloc context %d (%p)\n", map_replace_ptr, mm));
+
+ /* did we replace an mm ? */
+
+ old_mm = page_id_map[map_replace_ptr];
+
+ if(old_mm) {
+ /* throw out any TLB entries belonging to the mm we replace
+ * in the map
+ */
+ flush_tlb_mm(old_mm);
+
+ old_mm->context = NO_CONTEXT;
+ }
+
+ /* insert it into the page_id_map */
+
+ mm->context = map_replace_ptr;
+ page_id_map[map_replace_ptr] = mm;
+
+ map_replace_ptr++;
+
+ if(map_replace_ptr == INVALID_PAGEID)
+ map_replace_ptr = 0; /* wrap around */
+}
+
+/*
+ * if needed, get a new MMU context for the mm. otherwise nothing is done.
+ */
+
+void
+get_mmu_context(struct mm_struct *mm)
+{
+ if(mm->context == NO_CONTEXT)
+ alloc_context(mm);
+}
+
+/* called by __exit_mm to destroy the used MMU context if any before
+ * destroying the mm itself. this is only called when the last user of the mm
+ * drops it.
+ *
+ * the only thing we really need to do here is mark the used PID slot
+ * as empty.
+ */
+
+void
+destroy_context(struct mm_struct *mm)
+{
+ if(mm->context != NO_CONTEXT) {
+ D(printk("destroy_context %d (%p)\n", mm->context, mm));
+ flush_tlb_mm(mm); /* TODO this might be redundant ? */
+ page_id_map[mm->context] = NULL;
+ /* mm->context = NO_CONTEXT; redundant.. mm will be freed */
+ }
+}
+
+/* called once during VM initialization, from init.c */
+
+void __init
+tlb_init(void)
+{
+ int i;
+
+ /* clear the page_id map */
+
+ for (i = 1; i < sizeof (page_id_map) / sizeof (page_id_map[0]); i++)
+ page_id_map[i] = NULL;
+
+ /* invalidate the entire TLB */
+
+ flush_tlb_all();
+
+ /* the init_mm has context 0 from the boot */
+
+ page_id_map[0] = &init_mm;
+}