The original version of DDEKit.

1 files changed, 219 insertions, 0 deletions

diff --git a/libddekit/pgtab.c b/libddekit/pgtab.c
new file mode 100644
index 00000000..3c39f54f
--- /dev/null
+++ b/libddekit/pgtab.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
+ *
+ * This implementation uses l4rm (especially the AVL tree and userptr) to
+ * manage virt->phys mappings. Each mapping region is represented by one
+ * pgtab_object that is kept in the l4rm region userptr.
+ *
+ * For this to work, dataspaces must be attached to l4rm regions!
+ */
+
+#include <l4/dde/ddekit/pgtab.h>
+#include <l4/dde/ddekit/memory.h>
+#include <l4/dde/ddekit/panic.h>
+
+#include <l4/l4rm/l4rm.h>
+#include <l4/lock/lock.h>
+#include <l4/util/macros.h>
+
+#include "config.h"
+
+
+/**
+ * "Page-table" object
+ */
+struct pgtab_object
+{
+	l4_addr_t va;    /* virtual start address */
+	l4_addr_t pa;    /* physical start address */
+
+	/* FIXME reconsider the following members */
+	l4_size_t size;
+	unsigned  type;  /* pgtab region type */
+	
+	struct pgtab_object * next;
+	struct pgtab_object * prev;
+};
+
+/**
+ * pa_list_head of page-table object list (for get_virtaddr())
+ */
+static struct pgtab_object pa_list_head = 
+	{
+		.va   = 0,
+		.pa   = 0,
+		.size = 0,
+		.next = &pa_list_head,
+		.prev = &pa_list_head
+	};
+
+static l4lock_t pa_list_lock = L4LOCK_UNLOCKED; 
+
+/*****************************
+ ** Page-table facility API **
+ *****************************/
+
+/**
+ * Get physical address for virtual address
+ *
+ * \param virtual  virtual address
+ * \return physical address or 0
+ */
+ddekit_addr_t ddekit_pgtab_get_physaddr(const void *virtual)
+{
+	/* find pgtab object */
+	struct pgtab_object *p = l4rm_get_userptr(virtual);
+	if (!p) {
+		/* XXX this is verbose */
+		LOG_Error("no virt->phys mapping for virtual address %p", virtual);
+		return 0;
+	}
+
+	/* return virt->phys mapping */
+	l4_size_t offset = (l4_addr_t) virtual - p->va;
+
+	return p->pa + offset;
+}
+
+/**
+ * Get virtual address for physical address
+ *
+ * \param physical  physical address
+ * \return virtual address or 0
+ */
+ddekit_addr_t ddekit_pgtab_get_virtaddr(const ddekit_addr_t physical)
+{
+	/* find pgtab object */
+	struct pgtab_object *p;
+	ddekit_addr_t retval = 0;
+	
+	/* find phys->virt mapping */
+	l4lock_lock(&pa_list_lock);
+	for (p = pa_list_head.next ; p != &pa_list_head ; p = p->next) {
+		if (p->pa <= (l4_addr_t)physical && 
+		    (l4_addr_t)physical < p->pa + p->size) {
+			l4_size_t offset = (l4_addr_t) physical - p->pa;
+			retval = p->va + offset;
+			break;
+		}
+	}
+	l4lock_unlock(&pa_list_lock);
+
+	if (!retval)
+		LOG_Error("no phys->virt mapping for physical address %p", (void*)physical);
+
+	return retval;
+}
+
+
+
+int ddekit_pgtab_get_type(const void *virtual)
+{
+	/* find pgtab object */
+	struct pgtab_object *p = l4rm_get_userptr(virtual);
+	if (!p) {
+		/* XXX this is verbose */
+		LOG_Error("no virt->phys mapping for %p", virtual);
+		return -1;
+	}
+
+	return p->type;
+}
+
+
+int ddekit_pgtab_get_size(const void *virtual)
+{
+	/* find pgtab object */
+	struct pgtab_object *p = l4rm_get_userptr(virtual);
+	if (!p) {
+		/* XXX this is verbose */
+		LOG_Error("no virt->phys mapping for %p", virtual);
+		return -1;
+	}
+
+	return p->size;
+}
+
+
+/**
+ * Clear virtual->physical mapping for VM region
+ *
+ * \param virtual   virtual start address for region
+ * \param type      pgtab type for region
+ */
+void ddekit_pgtab_clear_region(void *virtual, int type)
+{
+	struct pgtab_object *p;
+
+	/* find pgtab object */
+	p = (struct pgtab_object *)l4rm_get_userptr(virtual);
+	if (!p) {
+		/* XXX this is verbose */
+		LOG_Error("no virt->phys mapping for %p", virtual);
+		return;
+	}
+
+	/* reset userptr in region map */
+	/* XXX no error handling here */
+	l4rm_set_userptr(virtual, 0);
+
+	/* remove pgtab object from list */
+	l4lock_lock(&pa_list_lock);
+	p->next->prev= p->prev;
+	p->prev->next= p->next;
+	l4lock_unlock(&pa_list_lock);
+	
+	/* free pgtab object */
+	ddekit_simple_free(p);
+}
+
+
+/**
+ * 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      pgtab type for region
+ */
+void ddekit_pgtab_set_region(void *virtual, ddekit_addr_t physical, int pages, int type)
+{
+	/* allocate pgtab object */
+	struct pgtab_object *p = ddekit_simple_malloc(sizeof(*p));
+	if (!p) {
+		LOG_Error("ddekit heap exhausted");
+		return;
+	}
+
+	/* initialize pgtab object */
+	p->va   = l4_trunc_page(virtual);
+	p->pa   = l4_trunc_page(physical);
+	p->size = pages * L4_PAGESIZE;
+	p->type = type;
+
+	l4lock_lock(&pa_list_lock);
+	p->next=pa_list_head.next;
+	p->prev=&pa_list_head;
+	pa_list_head.next->prev=p;
+	pa_list_head.next=p;
+	l4lock_unlock(&pa_list_lock);
+
+	/* set userptr in region map to pgtab object */
+	int err = l4rm_set_userptr((void *)p->va, p);
+	if (err) {
+		LOG_Error("l4rm_set_userptr returned %d", err);
+		ddekit_panic("l4rm_set_userptr");
+		ddekit_simple_free(p);
+	}
+}
+
+void ddekit_pgtab_set_region_with_size(void *virt, ddekit_addr_t phys, int size, int type)
+{
+	int p = l4_round_page(size);
+	p >>= L4_PAGESHIFT;
+	ddekit_pgtab_set_region(virt, phys, p, type);
+}
+