kernel/amd64: pmap: Add initial pmap code

Signed-off-by: Ian Moffett <ian@osmora.org>

1 files changed, 64 insertions, 0 deletions

diff --git a/sys/include/vm/pmap.h b/sys/include/vm/pmap.h
new file mode 100644
index 0000000..ec669a8
--- /dev/null
+++ b/sys/include/vm/pmap.h
@@ -0,0 +1,64 @@
+/*
+ * Copyright (c) 2023-2024 Ian Marco Moffett and the Osmora Team.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of Hyra nor the names of its
+ *    contributors may be used to endorse or promote products derived from
+ *    this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef _VM_PMAP_H_
+#define _VM_PMAP_H_
+
+#include <sys/types.h>
+#include <machine/vas.h>
+
+/* Protection flags for mappings */
+#define PROT_READ       0x00000000UL
+#define PROT_WRITE      BIT(0)      /* Writable */
+#define PROT_EXEC       BIT(1)      /* Executable */
+#define PROT_USER       BIT(2)      /* User accessible */
+
+typedef uint32_t vm_prot_t;
+
+/*
+ * Fetch the current address space.
+ */
+struct vas pmap_read_vas(void);
+
+/*
+ * Switch the virtual address space.
+ */
+void pmap_switch_vas(struct vas vas);
+
+/*
+ * Create a virtual memory mapping of a single page.
+ */
+int pmap_map(struct vas vas, vaddr_t va, paddr_t pa, vm_prot_t prot);
+
+/*
+ * Unmap a virtual memory mapping of a single page.
+ */
+int pmap_unmap(struct vas vas, vaddr_t va);
+
+#endif  /* !_VM_PMAP_H_ */