aboutsummaryrefslogtreecommitdiff
path: root/kernel/l0/kmain.c
blob: 416b802954ddca142c12c90041bb477f09beeee4 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
#include <multiboot.h>
#include <config.h>
#include <dbglog.h>
#include <sys.h>

#include <gdt.h>
#include <idt.h>
#include <frame.h>
#include <paging.h>
#include <region.h>
#include <kmalloc.h>

#include <thread.h>

#include <slab_alloc.h>

extern char k_end_addr;	// defined in linker script : 0xC0000000 plus kernel stuff

void breakpoint_handler(registers_t *regs) {
	dbg_printf("Breakpoint! (int3)\n");
	BOCHS_BREAKPOINT;
}

void region_test1() {
	void* p = region_alloc(0x1000, REGION_T_HW, 0);
	dbg_printf("Allocated one-page region: 0x%p\n", p);
	dbg_print_region_info();
	void* q = region_alloc(0x1000, REGION_T_HW, 0);
	dbg_printf("Allocated one-page region: 0x%p\n", q);
	dbg_print_region_info();
	void* r = region_alloc(0x2000, REGION_T_HW, 0);
	dbg_printf("Allocated two-page region: 0x%p\n", r);
	dbg_print_region_info();
	void* s = region_alloc(0x10000, REGION_T_CORE_HEAP, 0);
	dbg_printf("Allocated 16-page region: 0x%p\n", s);
	dbg_print_region_info();
	region_free(p);
	dbg_printf("Freed region 0x%p\n", p);
	dbg_print_region_info();
	region_free(q);
	dbg_printf("Freed region 0x%p\n", q);
	dbg_print_region_info();
	region_free(r);
	dbg_printf("Freed region 0x%p\n", r);
	dbg_print_region_info();
	region_free(s);
	dbg_printf("Freed region 0x%p\n", s);
	dbg_print_region_info();
}

void region_test2() {
	// allocate a big region and try to write into it
	dbg_printf("Begin region test 2...");
	const size_t n = 200;
	void* p0 = region_alloc(n * PAGE_SIZE, REGION_T_HW, default_allocator_pf_handler);
	for (size_t i = 0; i < n; i++) {
		uint32_t *x = (uint32_t*)(p0 + i * PAGE_SIZE);
		x[0] = 12;
		x[1] = (i * 20422) % 122;
	}
	// unmap memory
	for (size_t i = 0; i < n; i++) {
		void* p = p0 + i * PAGE_SIZE;
		uint32_t *x = (uint32_t*)p;
		ASSERT(x[1] == (i * 20422) % 122);

		uint32_t f = pd_get_frame(p);
		ASSERT(f != 0);
		pd_unmap_page(p);
		ASSERT(pd_get_frame(p) == 0);

		frame_free(f, 1);
	}
	region_free(p0);
	dbg_printf("OK\n");
}

void kmalloc_test(void* kernel_data_end) {
	// Test kmalloc !
	dbg_print_region_info();
	dbg_printf("Begin kmalloc test...\n");
	const int m = 200;
	uint16_t** ptr = kmalloc(m * sizeof(uint32_t));
	for (int i = 0; i < m; i++) {
		size_t s = 1 << ((i * 7) % 11 + 2);
		ptr[i] = (uint16_t*)kmalloc(s);
		ASSERT((void*)ptr[i] >= kernel_data_end && (size_t)ptr[i] < 0xFFC00000);
		*ptr[i] = ((i * 211) % 1024);
	}
	dbg_printf("Fully allocated.\n");
	dbg_print_region_info();
	for (int i = 0; i < m; i++) {
		for (int j = i; j < m; j++) {
			ASSERT(*ptr[j] == (j * 211) % 1024);
		}
		kfree(ptr[i]);
	}
	kfree(ptr);
	dbg_printf("Kmalloc test OK.\n");
	dbg_print_region_info();
}

void test_thread(void* a) {
	int i = 0;
	while(1) {
		dbg_printf("b");
		for (int x = 0; x < 100000; x++) asm volatile("xor %%ebx, %%ebx":::"%ebx");
		if (++i == 8) {
			yield();
			i = 0;
		}
	}
}
void kernel_init_stage2(void* data) {
	thread_t *tb = new_thread(test_thread);
	resume_thread_with_result(tb, 0, false);

	dbg_print_region_info();
	dbg_print_frame_stats();

	while(1) {
		dbg_printf("a");
		for (int x = 0; x < 100000; x++) asm volatile("xor %%ebx, %%ebx":::"%ebx");
	}
	PANIC("Reached kmain end! Falling off the edge.");
}
 
void kmain(struct multiboot_info_t *mbd, int32_t mb_magic) {
	dbglog_setup();

	dbg_printf("Hello, kernel world!\n");
	dbg_printf("This is %s, version %s.\n", OS_NAME, OS_VERSION);

	ASSERT(mb_magic == MULTIBOOT_BOOTLOADER_MAGIC);

	gdt_init(); dbg_printf("GDT set up.\n");

	idt_init(); dbg_printf("IDT set up.\n");
	idt_set_ex_handler(EX_BREAKPOINT, breakpoint_handler);
	asm volatile("int $0x3");	// test breakpoint

	size_t total_ram = ((mbd->mem_upper + mbd->mem_lower) * 1024);
	dbg_printf("Total ram: %d Kb\n", total_ram / 1024);

	// used for allocation of data structures before malloc is set up
	// a pointer to this pointer is passed to the functions that might have
	// to allocate memory ; they just increment it of the allocated quantity
	void* kernel_data_end = &k_end_addr;

	frame_init_allocator(total_ram, &kernel_data_end);
	dbg_printf("kernel_data_end: 0x%p\n", kernel_data_end);
	dbg_print_frame_stats();

	paging_setup(kernel_data_end);
	dbg_printf("Paging seems to be working!\n");

	BOCHS_BREAKPOINT;

	region_allocator_init(kernel_data_end);
	region_test1();
	region_test2();

	kmalloc_setup();
	kmalloc_test(kernel_data_end);

	// enter multi-threading mode
	// interrupts are enabled at this moment, so all
	// code run from now on should be preemtible (ie thread-safe)
	threading_setup(kernel_init_stage2, 0);
	PANIC("Should never come here.");
}

/* vim: set ts=4 sw=4 tw=0 noet :*/