From 19916128eeb882338f39c756945ad978eab13a49 Mon Sep 17 00:00:00 2001 From: Ian Moffett Date: Mon, 10 Jun 2024 23:51:40 -0400 Subject: kernel: vm: Add initial code for MI layer Add initial code for the machine independent virtual memory layer Signed-off-by: Ian Moffett --- sys/include/vm/map.h | 40 ++++++++++++++++ sys/vm/vm_map.c | 132 +++++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 172 insertions(+) create mode 100644 sys/include/vm/map.h create mode 100644 sys/vm/vm_map.c diff --git a/sys/include/vm/map.h b/sys/include/vm/map.h new file mode 100644 index 0000000..936df5e --- /dev/null +++ b/sys/include/vm/map.h @@ -0,0 +1,40 @@ +/* + * 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_MAP_H_ +#define _VM_MAP_H_ + +#include +#include +#include + +int vm_map(struct vas vas, vaddr_t va, paddr_t pa, vm_prot_t prot, size_t count); +int vm_unmap(struct vas vas, vaddr_t va, size_t count); + +#endif /* !_VM_MAP_H_ */ diff --git a/sys/vm/vm_map.c b/sys/vm/vm_map.c new file mode 100644 index 0000000..d89cff5 --- /dev/null +++ b/sys/vm/vm_map.c @@ -0,0 +1,132 @@ +/* + * 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. + */ + +#include +#include +#include +#include +#include +#include + +/* + * Create/destroy virtual memory mappings in a specific + * address space. + * + * @vas: Address space. + * @va: Virtual address. + * @pa: Physical address (zero if `unmap` is true) + * @prot: Protection flags (zero if `unmap` is true) + * @unmap: True to unmap. + * @count: Count of bytes to be mapped which is aligned to the + * machine's page granularity. + * + * Returns 0 on success. On failure, this routine + * returns a less than zero value or greater than zero + * value that contains the offset into the memory where the + * mapping failed. + */ +static int +vm_map_modify(struct vas vas, vaddr_t va, paddr_t pa, vm_prot_t prot, bool unmap, + size_t count) +{ + size_t misalign = va & (DEFAULT_PAGESIZE - 1); + int s; + + if (count == 0) { + return -EINVAL; + } + + /* Ensure we fully span pages */ + count = ALIGN_UP(count + misalign, DEFAULT_PAGESIZE); + va = ALIGN_DOWN(va, DEFAULT_PAGESIZE); + pa = ALIGN_DOWN(pa, DEFAULT_PAGESIZE); + + for (uintptr_t i = 0; i < count; i += DEFAULT_PAGESIZE) { + /* See if we should map or unmap the range */ + if (unmap) { + s = pmap_unmap(vas, va + i); + } else { + s = pmap_map(vas, va + i, pa + i, prot); + } + + if (s != 0) { + /* Something went wrong, return the offset */ + return i; + } + } + + return 0; +} + +/* + * Create a virtual memory mapping in a specific + * address space. + * + * @vas: Address space. + * @va: Virtual address. + * @pa: Physical address. + * @prot: Protection flags. + * @count: Count of bytes to be mapped (aligned to page granularity). + * + * Returns 0 on success, and a less than zero errno + * on failure. + */ +int +vm_map(struct vas vas, vaddr_t va, paddr_t pa, vm_prot_t prot, size_t count) +{ + int retval; + + va = ALIGN_UP(va, DEFAULT_PAGESIZE); + retval = vm_map_modify(vas, va, pa, prot, false, count); + + /* Return on success */ + if (retval == 0) + return 0; + + /* Failure, clean up */ + for (int i = 0; i < retval; i += DEFAULT_PAGESIZE) { + pmap_unmap(vas, va + i); + } + + return -1; +} + +/* + * Unmap a virtual memory mapping in a specific + * address space. + * + * @vas: Address space. + * @va: Virtual address to start unmapping at. + * @count: Bytes to unmap (aligned to page granularity) + */ +int +vm_unmap(struct vas vas, vaddr_t va, size_t count) +{ + return vm_map_modify(vas, va, 0, 0, true, count); +} -- cgit v1.2.3