The original version of DDEKit.

1 files changed, 219 insertions, 0 deletions

diff --git a/libddekit/pgtab-old.c b/libddekit/pgtab-old.c
new file mode 100644
index 00000000..2b13698a
--- /dev/null
+++ b/libddekit/pgtab-old.c
@@ -0,0 +1,219 @@
+/*
+ * \brief   Virtual page-table facility
+ * \author  Thomas Friebel <tf13@os.inf.tu-dresden.de>
+ * \author  Christian Helmuth <ch12@os.inf.tu-dresden.de>
+ * \date    2006-11-01
+ *
+ * Implementation of page tables for saving virt->phys assignments.
+ *
+ * FIXME: This works for 32-bit architectures only! (Mostly because of pgtab.h.)
+ */
+
+#include <l4/dde/ddekit/pgtab.h>
+
+#include <l4/sys/l4int.h>
+#include <l4/sys/consts.h>
+#include <l4/util/macros.h>
+#include <l4/dm_mem/dm_mem.h>
+#include <l4/log/l4log.h>
+
+
+/**********************************
+ ** Page-table utility functions **
+ **********************************/
+
+/* some useful consts */
+enum
+{
+	PDIR_SHIFT   = L4_SUPERPAGESHIFT,  /* readable alias */
+	PDIR_MASK    = L4_SUPERPAGEMASK,   /* readable alias */
+	PDIR_ENTRIES = (1 << (L4_MWORD_BITS - PDIR_SHIFT)),
+	PTAB_ENTRIES = (1 << (PDIR_SHIFT - L4_PAGESHIFT)),
+	PTAB_SIZE    = (sizeof(void*) * PTAB_ENTRIES)
+};
+
+/**
+ * Page table entry.
+ * bit 00-01: type, 0->largemalloc 1->slab page 2->contigmalloc (PTE_TYPE_*)
+ * bit 02-11: size in number of pages
+ * bit 12-31: physical page address
+ */
+typedef union
+{
+	unsigned compact;
+	struct
+	{
+		unsigned type  :  2;
+		unsigned pages : 10;
+		unsigned phys  : 20;
+	} components;
+} ddekit_pte;
+
+/**
+ * Calculate offset of address in page directory - page-table number
+ */
+static inline unsigned pt_num(l4_addr_t addr) {
+	return addr >> PDIR_SHIFT; }
+
+
+/**
+ * Calculate offset of address in page table - page number
+ */
+static inline unsigned pg_num(l4_addr_t addr) {
+	return (addr & ~PDIR_MASK) >> L4_PAGESHIFT; }
+
+
+/* page directory */
+static ddekit_pte *page_dir[PDIR_ENTRIES];
+
+
+/**
+ * Get page-table entry
+ */
+static inline ddekit_pte ddekit_get_pte(void *p)
+{
+	l4_addr_t addr = (l4_mword_t)p;
+	ddekit_pte *tab;
+
+	tab = page_dir[pt_num(addr)];
+	if (!tab) return (ddekit_pte) 0U;
+
+	return tab[pg_num(addr)];
+}
+
+
+/**
+ * Set page-table entry
+ */
+static inline void ddekit_set_pte(void *p, ddekit_pte pte)
+{
+	l4_addr_t addr = (l4_addr_t) p;
+	ddekit_pte *tab;
+
+	tab = page_dir[pt_num(addr)];
+	if (!tab) {
+		/* create new page table */
+		tab = (ddekit_pte *)
+		      l4dm_mem_allocate_named(PTAB_SIZE, L4DM_CONTIGUOUS|L4DM_PINNED|L4RM_MAP,
+		                              "ddekit ptab");
+		Assert(tab);
+
+		memset(tab, 0, PTAB_SIZE);
+		page_dir[pt_num(addr)] = tab;
+
+		if (1) {
+			l4_addr_t a = l4_trunc_superpage(addr);
+			LOG("created page table for range [0x%08lx,0x%08lx) @ %p\n",
+			     a, a + L4_SUPERPAGESIZE, tab);
+		}
+
+	}
+
+	tab[pg_num(addr)] = pte;
+}
+
+
+/*****************************
+ ** Page-table facility API **
+ *****************************/
+
+/**
+ * Set virtual->physical mapping for VM region
+ *
+ * \param virtual   virtual start address for region
+ * \param physical  physical start address for region
+ * \param pages     number of pages in region
+ * \param type      pte type for region
+ */
+void ddekit_pte_set_region(void *virtual, ddekit_addr_t physical, int pages, int type)
+{
+	ddekit_pte new;
+
+#ifdef INVARIANTS
+	ddekit_pte pte;
+	/* assert pte not set yet */
+	pte = ddekit_get_pte(virtual);
+	LOGd(pte.compact, "first pte already set! pte=0x%04x", pte.compact);
+#endif
+
+	/* build pte */
+	new.components.type  = type;
+	new.components.pages = pages;
+	new.components.phys  = physical >> L4_PAGESHIFT;
+
+	/* set first pte */
+	ddekit_set_pte(virtual, new);
+
+	/* continuation pte-s don't have pages set */
+	new.components.pages = 0;
+
+	/* set continuation pte-s */
+	for (pages--; pages; pages--) {
+		/* prepare continuation pte */
+		virtual += L4_PAGESIZE;
+		new.components.phys++;
+
+#ifdef INVARIANTS
+		/* assert pte not set yet */
+		pte = ddekit_get_pte(virtual);
+		LOGd(pte.compact, "continuation pte already set! pte=0x%04x", pte.compact);
+#endif
+
+		/* set continuation pte */
+		ddekit_set_pte(virtual, new);
+	}
+}
+
+
+/**
+ * Clear virtual->physical mapping for VM region
+ *
+ * \param virtual   virtual start address for region
+ * \param type      pte type for region
+ *
+ * XXX unused page-tables not free'd
+ */
+void ddekit_pte_clear_region(void *virtual, int type)
+{
+	ddekit_pte pte;
+	int pages = 0;
+	pte = ddekit_get_pte(virtual);
+	/* get number of pages from pte */
+	pages = pte.components.pages;
+	/* assert pages != 0 */
+	if (pages==0) {
+		LOG("continuation pte found at base");
+		return;
+	}
+	/* assert pte set and of correct type */
+#ifdef INVARIANTS
+	LOGd(! pte.compact, "pte is already clear");
+	LOGd(pte.components.type!=type, "pte of wrong type");
+#endif
+	/* clear first pte */
+	ddekit_set_pte(virtual, (ddekit_pte) 0U);
+	/* clear continuation pte-s */
+	for (pages--; pages; pages--) {
+		virtual += L4_PAGESIZE;
+
+#ifdef INVARIANTS
+		/* assert pte set and of correct type */
+		pte = ddekit_get_pte(virtual);
+		if (! pte.compact) {
+			LOG("pte is already clear");
+			break;
+		}
+		if (pte.components.type!=type) {
+			LOG("pte of wrong type");
+			break;
+		}
+		if (pte.components.pages) {
+			LOG("unexpected non-continuation pte found");
+			break;
+		}
+#endif
+
+		ddekit_set_pte(virtual, (ddekit_pte) 0U);
+	}
+}
+