Get mem mapping from bootloader

This commit is contained in:
Mathieu Maret 2021-01-23 00:42:09 +01:00
parent 77b495e382
commit 8309174f1a
6 changed files with 220 additions and 38 deletions

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@ -1,5 +1,6 @@
#pragma once
#include "stdarg.h"
#include "minmax.h"
#define islower(c) (('a' <= (c)) && ((c) <= 'z'))
#define isupper(c) (('A' <= (c)) && ((c) <= 'Z'))

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@ -37,7 +37,9 @@ void idleThread(void *arg)
// https://www.gnu.org/software/grub/manual/multiboot/html_node/Boot-information-format.html#Boot%20information%20format
void kmain(unsigned long magic, unsigned long addr)
{
unsigned long upperMem = 0;
unsigned long upperMemKB = 0;
int memMapAvailable = 0;
paddr_t lastUsedByMem;
VGASetup(BLACK, GREEN);
cursorEnable(14, 15);
@ -53,7 +55,7 @@ void kmain(unsigned long magic, unsigned long addr)
/* Are mem_* valid? */
if (CHECK_FLAG(mbi->flags, 0)) {
printf("mem_lower = %dKiB mem_upper %dKiB\n", mbi->mem_lower, mbi->mem_upper);
upperMem = mbi->mem_upper;
upperMemKB = mbi->mem_upper;
}
/* Is boot_device valid? */
@ -79,31 +81,43 @@ void kmain(unsigned long magic, unsigned long addr)
}
if (CHECK_FLAG(mbi->flags, 6)) {
struct multiboot_mmap_entry *mmap = (struct multiboot_mmap_entry *)mbi->mmap_addr;
uint size = mbi->mmap_length / sizeof(struct multiboot_mmap_entry);
pr_devel("mmap buffer at %d size %d %d\n", mbi->mmap_addr, mbi->mmap_length,
sizeof(multiboot_memory_map_t));
for (uint i = 0; i < size; i++) {
printf("base_addr 0x%x 0x%x, length = 0x%x 0x%x, type = 0x%x\n",
(unsigned)(mmap[i].addr >> 32), (unsigned)(mmap[i].addr & 0xffffffff),
(unsigned)(mmap[i].len >> 32), (unsigned)(mmap[i].len & 0xffffffff),
(uint32_t)mmap[i].type);
}
memMapAvailable = 1;
}
}
if (upperMem == 0) {
if (upperMemKB == 0) {
printf("Cannot get upper phy mem bound. Using default value 32MB\n");
upperMem = 32 * 1024;
upperMemKB = 32 * 1024;
}
printf("Setting up Pagination\n");
paddr_t lastUserByMem;
memSetup(upperMem, &lastUserByMem);
printf("Setting up Mem\n");
memSetup(upperMemKB, &lastUsedByMem);
if (memMapAvailable) {
multiboot_info_t *mbi = (multiboot_info_t *)addr;
struct multiboot_mmap_entry *mmap = (struct multiboot_mmap_entry *)mbi->mmap_addr;
uint size = mbi->mmap_length / sizeof(struct multiboot_mmap_entry);
pr_devel("mmap buffer at 0x%x with %d entries\n", mbi->mmap_addr, size);
for (uint i = 0; i < size; i++) {
printf(" base_addr 0x%x 0x%x, length = 0x%x 0x%x, type = 0x%x\n",
(unsigned)(mmap[i].addr >> 32), (unsigned)(mmap[i].addr & 0xffffffff),
(unsigned)(mmap[i].len >> 32), (unsigned)(mmap[i].len & 0xffffffff),
(uint32_t)mmap[i].type);
memAddBank(
max(mmap[i].addr, (multiboot_uint64_t)lastUsedByMem),
min((multiboot_uint64_t)(upperMemKB * 1024), mmap[i].addr + mmap[i].len),
mmap[i].type == MULTIBOOT_MEMORY_AVAILABLE);
}
} else {
printf("Cannot get memory Mapping information, using default value\n");
memAddBank(0, lastUsedByMem, 0);
memAddBank(lastUsedByMem, upperMemKB * 1024, 1);
}
#ifdef RUN_TEST
testPhymem();
#endif
pagingSetup(lastUserByMem);
printf("Setting up Pagination\n");
pagingSetup(lastUsedByMem);
printf("Setting up IRQ handlers\n");
irqSetRoutine(IRQ_KEYBOARD, keyboard_handler);

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@ -7,50 +7,49 @@
static struct memDesc *pageDesc = (struct memDesc *)&__ld_kernel_end;
static struct memDesc *freePage;
static struct memDesc *usedPage;
static unsigned long memBottom;
static unsigned long memTop;
static unsigned long allocatedPage = 0;
int memSetup(paddr_t upperMem, paddr_t *lastPageUsedOut)
int memSetup(paddr_t upperMemKB, paddr_t *lastMemUsedOut)
{
list_init(freePage);
list_init(usedPage);
// Align upper mem (in kB) on page size even if it does loose a page
upperMem = ALIGN_DOWN(upperMem, PAGE_SIZE / 1024);
unsigned long nbPage = ((upperMem) / (PAGE_SIZE / 1024));
upperMemKB = ALIGN_DOWN(upperMemKB, PAGE_SIZE / 1024);
unsigned long nbPage = ((upperMemKB) / (PAGE_SIZE / 1024));
printf("Available Mem from 0x%x to 0x%x: %dMB and %dPages(%d)\n", &__ld_kernel_end,
upperMem * 1024, (upperMem * 1024 - (uint32_t)&__ld_kernel_end) / (1024 * 1024),
upperMemKB * 1024, (upperMemKB * 1024 - (uint32_t)&__ld_kernel_end) / (1024 * 1024),
nbPage, PAGE_SIZE);
// Memory description is stored after the kernel. We need some place to store it
unsigned long pageDescEnd = (unsigned long)pageDesc + nbPage * sizeof(struct memDesc);
uint lastPageUsed = (pageDescEnd >> PAGE_SHIFT) + 1;
memBottom = lastPageUsed << PAGE_SHIFT;
memTop = upperMem * 1024;
*lastPageUsedOut = pageDescEnd;
*lastMemUsedOut = ALIGN(pageDescEnd, PAGE_SIZE);
for (uint i = 0; i < nbPage; i++) {
memAddBank(0, *lastMemUsedOut, 0);
return 0;
}
int memAddBank(paddr_t bottomMem, paddr_t topMem, int isFree)
{
for (uint i = (bottomMem >> PAGE_SHIFT); i < (topMem >> PAGE_SHIFT); i++) {
struct memDesc *mem = &pageDesc[i];
if (i < lastPageUsed) {
mem->ref = 1;
list_add_tail(usedPage, mem);
} else {
if (isFree) {
mem->ref = 0;
list_add_tail(freePage, mem);
} else {
mem->ref = 1;
list_add_tail(usedPage, mem);
}
mem->phy_addr = i * PAGE_SIZE;
}
return 0;
}
struct memDesc *addr2memDesc(paddr_t addr)
{
if (addr > memTop || addr < memBottom)
return NULL;
int idx = addr >> PAGE_SHIFT;
return pageDesc + idx;
}

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@ -16,6 +16,7 @@ struct memDesc {
};
int memSetup(paddr_t upperMem, paddr_t *lastUsed);
int memAddBank(paddr_t bottomMem, paddr_t topMem, int isFree);
paddr_t allocPhyPage(uint nbPage);
int unrefPhyPage(paddr_t addr);
int refPhyPage(paddr_t addr);

169
core/minmax.h Normal file
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@ -0,0 +1,169 @@
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _LINUX_MINMAX_H
#define _LINUX_MINMAX_H
/*
* From linux kernel include/linux/compiler_types.h
*/
#define ___PASTE(a,b) a##b
#define __PASTE(a,b) ___PASTE(a,b)
/*
* From Linux kernel include/linux/compiler.h
*/
/* Not-quite-unique ID. */
#ifndef __UNIQUE_ID
# define __UNIQUE_ID(prefix) __PASTE(__PASTE(__UNIQUE_ID_, prefix), __LINE__)
#endif
/*
* min()/max()/clamp() macros must accomplish three things:
*
* - avoid multiple evaluations of the arguments (so side-effects like
* "x++" happen only once) when non-constant.
* - perform strict type-checking (to generate warnings instead of
* nasty runtime surprises). See the "unnecessary" pointer comparison
* in __typecheck().
* - retain result as a constant expressions when called with only
* constant expressions (to avoid tripping VLA warnings in stack
* allocation usage).
*/
#define __typecheck(x, y) \
(!!(sizeof((typeof(x) *)1 == (typeof(y) *)1)))
/*
* This returns a constant expression while determining if an argument is
* a constant expression, most importantly without evaluating the argument.
* Glory to Martin Uecker <Martin.Uecker@med.uni-goettingen.de>
*/
#define __is_constexpr(x) \
(sizeof(int) == sizeof(*(8 ? ((void *)((long)(x) * 0l)) : (int *)8)))
#define __no_side_effects(x, y) \
(__is_constexpr(x) && __is_constexpr(y))
#define __safe_cmp(x, y) \
(__typecheck(x, y) && __no_side_effects(x, y))
#define __cmp(x, y, op) ((x) op (y) ? (x) : (y))
#define __cmp_once(x, y, unique_x, unique_y, op) ({ \
typeof(x) unique_x = (x); \
typeof(y) unique_y = (y); \
__cmp(unique_x, unique_y, op); })
#define __careful_cmp(x, y, op) \
__builtin_choose_expr(__safe_cmp(x, y), \
__cmp(x, y, op), \
__cmp_once(x, y, __UNIQUE_ID(__x), __UNIQUE_ID(__y), op))
/**
* min - return minimum of two values of the same or compatible types
* @x: first value
* @y: second value
*/
#define min(x, y) __careful_cmp(x, y, <)
/**
* max - return maximum of two values of the same or compatible types
* @x: first value
* @y: second value
*/
#define max(x, y) __careful_cmp(x, y, >)
/**
* min3 - return minimum of three values
* @x: first value
* @y: second value
* @z: third value
*/
#define min3(x, y, z) min((typeof(x))min(x, y), z)
/**
* max3 - return maximum of three values
* @x: first value
* @y: second value
* @z: third value
*/
#define max3(x, y, z) max((typeof(x))max(x, y), z)
/**
* min_not_zero - return the minimum that is _not_ zero, unless both are zero
* @x: value1
* @y: value2
*/
#define min_not_zero(x, y) ({ \
typeof(x) __x = (x); \
typeof(y) __y = (y); \
__x == 0 ? __y : ((__y == 0) ? __x : min(__x, __y)); })
/**
* clamp - return a value clamped to a given range with strict typechecking
* @val: current value
* @lo: lowest allowable value
* @hi: highest allowable value
*
* This macro does strict typechecking of @lo/@hi to make sure they are of the
* same type as @val. See the unnecessary pointer comparisons.
*/
#define clamp(val, lo, hi) min((typeof(val))max(val, lo), hi)
/*
* ..and if you can't take the strict
* types, you can specify one yourself.
*
* Or not use min/max/clamp at all, of course.
*/
/**
* min_t - return minimum of two values, using the specified type
* @type: data type to use
* @x: first value
* @y: second value
*/
#define min_t(type, x, y) __careful_cmp((type)(x), (type)(y), <)
/**
* max_t - return maximum of two values, using the specified type
* @type: data type to use
* @x: first value
* @y: second value
*/
#define max_t(type, x, y) __careful_cmp((type)(x), (type)(y), >)
/**
* clamp_t - return a value clamped to a given range using a given type
* @type: the type of variable to use
* @val: current value
* @lo: minimum allowable value
* @hi: maximum allowable value
*
* This macro does no typechecking and uses temporary variables of type
* @type to make all the comparisons.
*/
#define clamp_t(type, val, lo, hi) min_t(type, max_t(type, val, lo), hi)
/**
* clamp_val - return a value clamped to a given range using val's type
* @val: current value
* @lo: minimum allowable value
* @hi: maximum allowable value
*
* This macro does no typechecking and uses temporary variables of whatever
* type the input argument @val is. This is useful when @val is an unsigned
* type and @lo and @hi are literals that will otherwise be assigned a signed
* integer type.
*/
#define clamp_val(val, lo, hi) clamp_t(typeof(val), val, lo, hi)
/**
* swap - swap values of @a and @b
* @a: first value
* @b: second value
*/
#define swap(a, b) \
do { typeof(a) __tmp = (a); (a) = (b); (b) = __tmp; } while (0)
#endif /* _LINUX_MINMAX_H */

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@ -14,8 +14,6 @@
void testPhymem(void)
{
printf("Testing memory PHY\n");
assert(refPhyPage((paddr_t)(&__ld_kernel_end)) == -1);
assert(refPhyPage((paddr_t)(&__ld_kernel_begin)) == -1);
struct memDesc *allocated_page_list;
struct memDesc
*page; // Cast in mem_desc to use it. In fact it's the addr of 4K free memory