From 1c4c7f88056f50987a5a4d40016d6e32dc5a0205 Mon Sep 17 00:00:00 2001 From: sigsegv7 Date: Wed, 11 Oct 2023 16:39:05 -0400 Subject: kernel: vm: Add PMAP abstraction Signed-off-by: sigsegv7 --- sys/arch/amd64/pmap.c | 50 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 50 insertions(+) create mode 100644 sys/arch/amd64/pmap.c (limited to 'sys/arch/amd64') diff --git a/sys/arch/amd64/pmap.c b/sys/arch/amd64/pmap.c new file mode 100644 index 0000000..0da80d9 --- /dev/null +++ b/sys/arch/amd64/pmap.c @@ -0,0 +1,50 @@ +/* + * Copyright (c) 2023 Ian Marco Moffett and the VegaOS 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 VegaOS 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. + */ + +#include +#include + +#define PTE_ADDR_MASK 0x000FFFFFFFFFF000 + +struct vas +pmap_read_vas(void) +{ + struct vas vas; + uintptr_t cr3_raw; + + __ASMV("mov %%cr3, %0" + : "=r" (cr3_raw) + ); + + vas.cr3_flags = cr3_raw & ~PTE_ADDR_MASK; + vas.top_level = cr3_raw & PTE_ADDR_MASK; + vas.use_l5_paging = false; /* TODO: Check for support */ + vas.lock.lock = 0; + return vas; +} -- cgit v1.2.3