SimpleOS

LXR

Navigation



Site hébergé par : enix

The LXR Cross Referencer for SOS

source navigation ]
diff markup ]
identifier search ]
general search ]
 
 
Article:1 ] [ 2 ] [ 3 ] [ 4 ] [ 5 ] [ 6 ] [ 6.5 ] [ 7 ] [ 7.5 ] [ 8 ] [ 9 ] [ 9.5 ]

Diff markup

Differences between /sos/main.c (Article 4) and /sos/main.c (Article 7.5)


001 /* Copyright (C) 2004  The SOS Team               001 /* Copyright (C) 2004  The SOS Team
002    Copyright (C) 1999  Free Software Foundatio << 
003                                                   002 
004    This program is free software; you can redi    003    This program is free software; you can redistribute it and/or
005    modify it under the terms of the GNU Genera    004    modify it under the terms of the GNU General Public License
006    as published by the Free Software Foundatio    005    as published by the Free Software Foundation; either version 2
007    of the License, or (at your option) any lat    006    of the License, or (at your option) any later version.
008                                                   007    
009    This program is distributed in the hope tha    008    This program is distributed in the hope that it will be useful,
010    but WITHOUT ANY WARRANTY; without even the     009    but WITHOUT ANY WARRANTY; without even the implied warranty of
011    MERCHANTABILITY or FITNESS FOR A PARTICULAR    010    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
012    GNU General Public License for more details    011    GNU General Public License for more details.
013                                                   012    
014    You should have received a copy of the GNU     013    You should have received a copy of the GNU General Public License
015    along with this program; if not, write to t    014    along with this program; if not, write to the Free Software
016    Foundation, Inc., 59 Temple Place - Suite 3    015    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
017    USA.                                           016    USA. 
018 */                                                017 */
019                                                   018 
020 /* Include definitions of the multiboot standa    019 /* Include definitions of the multiboot standard */
021 #include <bootstrap/multiboot.h>                  020 #include <bootstrap/multiboot.h>
022 #include <hwcore/idt.h>                           021 #include <hwcore/idt.h>
023 #include <hwcore/gdt.h>                           022 #include <hwcore/gdt.h>
024 #include <hwcore/irq.h>                           023 #include <hwcore/irq.h>
025 #include <hwcore/exception.h>                     024 #include <hwcore/exception.h>
026 #include <hwcore/i8254.h>                         025 #include <hwcore/i8254.h>
027 #include <sos/list.h>                             026 #include <sos/list.h>
028 #include <sos/physmem.h>                          027 #include <sos/physmem.h>
029 #include <hwcore/paging.h>                        028 #include <hwcore/paging.h>
030 #include <sos/list.h>                          !! 029 #include <hwcore/mm_context.h>
                                                   >> 030 #include <hwcore/swintr.h>
                                                   >> 031 #include <sos/kmem_vmm.h>
                                                   >> 032 #include <sos/kmalloc.h>
                                                   >> 033 #include <sos/time.h>
                                                   >> 034 #include <sos/thread.h>
                                                   >> 035 #include <sos/process.h>
                                                   >> 036 #include <sos/umem_vmm.h>
031 #include <sos/klibc.h>                            037 #include <sos/klibc.h>
032 #include <sos/assert.h>                           038 #include <sos/assert.h>
033 #include <drivers/x86_videomem.h>                 039 #include <drivers/x86_videomem.h>
034 #include <drivers/bochs.h>                        040 #include <drivers/bochs.h>
                                                   >> 041 #include <sos/calcload.h>
                                                   >> 042 #include <sos/umem_vmm.h>
                                                   >> 043 #include <sos/binfmt_elf32.h>
                                                   >> 044 #include <drivers/zero.h>
035                                                   045 
036                                                   046 
037 /* Helper function to display each bits of a 3    047 /* Helper function to display each bits of a 32bits integer on the
038    screen as dark or light carrets */             048    screen as dark or light carrets */
039 static void display_bits(unsigned char row, un !! 049 void display_bits(unsigned char row, unsigned char col,
040                          unsigned char attribu !! 050                   unsigned char attribute,
041                          sos_ui32_t integer)   !! 051                   sos_ui32_t integer)
042 {                                                 052 {
043   int i;                                          053   int i;
044   /* Scan each bit of the integer, MSb first *    054   /* Scan each bit of the integer, MSb first */
045   for (i = 31 ; i >= 0 ; i--)                     055   for (i = 31 ; i >= 0 ; i--)
046     {                                             056     {
047       /* Test if bit i of 'integer' is set */     057       /* Test if bit i of 'integer' is set */
048       int bit_i = (integer & (1 << i));           058       int bit_i = (integer & (1 << i));
049       /* Ascii 219 => dark carret, Ascii 177 =    059       /* Ascii 219 => dark carret, Ascii 177 => light carret */
050       unsigned char ascii_code = bit_i?219:177    060       unsigned char ascii_code = bit_i?219:177;
051       sos_x86_videomem_putchar(row, col++,        061       sos_x86_videomem_putchar(row, col++,
052                                attribute,         062                                attribute,
053                                ascii_code);       063                                ascii_code);
054     }                                             064     }
055 }                                                 065 }
056                                                   066 
057                                                   067 
058 /* Clock IRQ handler */                           068 /* Clock IRQ handler */
059 static void clk_it(int intid)                     069 static void clk_it(int intid)
060 {                                                 070 {
061   static sos_ui32_t clock_count = 0;              071   static sos_ui32_t clock_count = 0;
062                                                   072 
063   display_bits(0, 48,                             073   display_bits(0, 48,
064                SOS_X86_VIDEO_FG_LTGREEN | SOS_    074                SOS_X86_VIDEO_FG_LTGREEN | SOS_X86_VIDEO_BG_BLUE,
065                clock_count);                      075                clock_count);
066   clock_count++;                                  076   clock_count++;
067                                                   077 
068 }                                              !! 078   /* Execute the expired timeout actions (if any) */
                                                   >> 079   sos_time_do_tick();
069                                                   080 
070 /* Page fault exception handler */             !! 081   /* Update scheduler statistics and status */
071 static void pgflt_ex(int exid)                 !! 082   sos_sched_do_timer_tick();
072 {                                              << 
073   sos_bochs_printf("Got page fault\n");        << 
074   sos_x86_videomem_printf(10, 30,              << 
075                           SOS_X86_VIDEO_FG_LTR << 
076                           "Got EXPECTED (?) Pa << 
077   for (;;) ;                                   << 
078 }                                                 083 }
079                                                   084 
080 static void test_paging(sos_vaddr_t sos_kernel !! 085 
                                                   >> 086 /* ======================================================================
                                                   >> 087  * Page fault exception handling
                                                   >> 088  */
                                                   >> 089 
                                                   >> 090 
                                                   >> 091 /* Page fault exception handler with demand paging for the kernel */
                                                   >> 092 static void pgflt_ex(int intid, struct sos_cpu_state *ctxt)
081 {                                                 093 {
082   /* The (linear) address of the page holding  !! 094   static sos_ui32_t demand_paging_count = 0;
083      currently executing */                    !! 095   struct sos_thread * cur_thr = sos_thread_get_current();
084   sos_vaddr_t vpage_code = SOS_PAGE_ALIGN_INF( !! 096   sos_vaddr_t faulting_vaddr  = sos_cpu_context_get_EX_faulting_vaddr(ctxt);
085                                                !! 097   sos_paddr_t ppage_paddr;
086   /* The new physical page that will hold the  << 
087   sos_paddr_t ppage_new;                       << 
088                                                << 
089   /* Where this page will be mapped temporaril << 
090      code into it: right after the kernel code << 
091   sos_vaddr_t vpage_tmp = sos_kernel_core_top_ << 
092                                                   098 
093   unsigned i;                                  !! 099   if (sos_cpu_context_is_in_user_mode(ctxt)
                                                   >> 100       || (cur_thr->fixup_uaccess.return_vaddr))
                                                   >> 101     {
                                                   >> 102       __label__ unforce_address_space;
                                                   >> 103       sos_bool_t need_to_setup_mmu;
                                                   >> 104       sos_ui32_t errcode = sos_cpu_context_get_EX_info(ctxt);
                                                   >> 105 
                                                   >> 106       /* Make sure to always stay in the interrupted thread's MMU
                                                   >> 107          configuration */
                                                   >> 108       need_to_setup_mmu = (cur_thr->squatted_mm_context
                                                   >> 109                            != sos_process_get_mm_context(cur_thr->process));
                                                   >> 110       if (need_to_setup_mmu)
                                                   >> 111         sos_thread_prepare_user_space_access(NULL, 0);
                                                   >> 112 
                                                   >> 113       if (SOS_OK ==
                                                   >> 114           sos_umem_vmm_try_resolve_page_fault(faulting_vaddr,
                                                   >> 115                                               errcode & (1 << 1),
                                                   >> 116                                               TRUE))
                                                   >> 117         goto unforce_address_space;
                                                   >> 118 
                                                   >> 119       /* If the page fault occured in kernel mode, return to kernel to
                                                   >> 120          the fixup address */
                                                   >> 121       if (! sos_cpu_context_is_in_user_mode(ctxt))
                                                   >> 122         {
                                                   >> 123           cur_thr->fixup_uaccess.faulted_uaddr = faulting_vaddr;
                                                   >> 124           sos_cpu_context_set_EX_return_address(ctxt,
                                                   >> 125                                                 cur_thr->fixup_uaccess.return_vaddr);
                                                   >> 126           goto unforce_address_space;
                                                   >> 127         }
                                                   >> 128 
                                                   >> 129       if (need_to_setup_mmu)
                                                   >> 130         sos_thread_end_user_space_access();
                                                   >> 131 
                                                   >> 132       sos_bochs_printf("Unresolved USER page Fault at instruction 0x%x on access to address 0x%x (info=%x)!\n",
                                                   >> 133                        sos_cpu_context_get_PC(ctxt),
                                                   >> 134                        (unsigned)faulting_vaddr,
                                                   >> 135                        (unsigned)sos_cpu_context_get_EX_info(ctxt));
                                                   >> 136       sos_bochs_printf("Terminating User thread\n");
                                                   >> 137       sos_thread_exit();
                                                   >> 138 
                                                   >> 139     unforce_address_space:
                                                   >> 140       if (need_to_setup_mmu)
                                                   >> 141         sos_thread_end_user_space_access();
                                                   >> 142       return;
                                                   >> 143     }
                                                   >> 144 
                                                   >> 145   /* Check if address is covered by any VMM range */
                                                   >> 146   if (! sos_kmem_vmm_is_valid_vaddr(faulting_vaddr))
                                                   >> 147     {
                                                   >> 148       /* No: The page fault is out of any kernel virtual region. For
                                                   >> 149          the moment, we don't handle this. */
                                                   >> 150       sos_display_fatal_error("Unresolved page Fault at instruction 0x%x on access to address 0x%x (info=%x)!",
                                                   >> 151                               sos_cpu_context_get_PC(ctxt),
                                                   >> 152                               (unsigned)faulting_vaddr,
                                                   >> 153                               (unsigned)sos_cpu_context_get_EX_info(ctxt));
                                                   >> 154       SOS_ASSERT_FATAL(! "Got page fault (note: demand paging is disabled)");
                                                   >> 155     }
094                                                   156 
095   /* Bind the page fault exception to one of o << 
096   sos_exception_set_routine(SOS_EXCEPT_PAGE_FA << 
097                             pgflt_ex);         << 
098                                                   157 
099   /*                                              158   /*
100    * Test 1: move the page where we execute th !! 159    * Demand paging in kernel space
101    * physical memory                           << 
102    */                                             160    */
103   sos_x86_videomem_printf(4, 0,                !! 161  
104                           SOS_X86_VIDEO_FG_LTG !! 162   /* Update the number of demand paging requests handled */
105                           "Moving current code !! 163   demand_paging_count ++;
                                                   >> 164   display_bits(0, 0,
                                                   >> 165                SOS_X86_VIDEO_FG_LTRED | SOS_X86_VIDEO_BG_BLUE,
                                                   >> 166                demand_paging_count);
                                                   >> 167 
                                                   >> 168   /* Allocate a new page for the virtual address */
                                                   >> 169   ppage_paddr = sos_physmem_ref_physpage_new(FALSE);
                                                   >> 170   if (! ppage_paddr)
                                                   >> 171     SOS_ASSERT_FATAL(! "TODO: implement swap. (Out of mem in demand paging because no swap for kernel yet !)");
                                                   >> 172   SOS_ASSERT_FATAL(SOS_OK == sos_paging_map(ppage_paddr,
                                                   >> 173                                             SOS_PAGE_ALIGN_INF(faulting_vaddr),
                                                   >> 174                                             FALSE,
                                                   >> 175                                             SOS_VM_MAP_PROT_READ
                                                   >> 176                                             | SOS_VM_MAP_PROT_WRITE
                                                   >> 177                                             | SOS_VM_MAP_ATOMIC));
                                                   >> 178   sos_physmem_unref_physpage(ppage_paddr);
                                                   >> 179 
                                                   >> 180   /* Ok, we can now return to interrupted context */
                                                   >> 181 }
                                                   >> 182 
106                                                   183 
107                                                   184 
108   /* Allocate a new physical page */           !! 185 /* ======================================================================
109   ppage_new = sos_physmem_ref_physpage_new(FAL !! 186  * An operating system MUST always have a ready thread ! Otherwise:
110   if (! ppage_new)                             !! 187  * what would the CPU have to execute ?!
                                                   >> 188  */
                                                   >> 189 static void idle_thread()
                                                   >> 190 {
                                                   >> 191   sos_ui32_t idle_twiddle = 0;
                                                   >> 192 
                                                   >> 193   while (1)
111     {                                             194     {
112       /* STOP ! No memory left */              !! 195       /* Remove this instruction if you get an "Invalid opcode" CPU
113       sos_x86_videomem_putstring(20, 0,        !! 196          exception (old 80386 CPU) */
114                                  SOS_X86_VIDEO !! 197       asm("hlt\n");
115                                    | SOS_X86_V !! 198 
116                                  "test_paging  !! 199       idle_twiddle ++;
117       return;                                  !! 200       display_bits(0, 0, SOS_X86_VIDEO_FG_GREEN | SOS_X86_VIDEO_BG_BLUE,
                                                   >> 201                    idle_twiddle);
                                                   >> 202       
                                                   >> 203       /* Lend the CPU to some other thread */
                                                   >> 204       sos_thread_yield();
118     }                                             205     }
                                                   >> 206 }
119                                                   207 
120   sos_x86_videomem_printf(5, 0,                !! 208 
121                           SOS_X86_VIDEO_FG_YEL !! 209 /* ======================================================================
122                           "Hello from the addr !! 210  * Kernel thread showing some CPU usage statistics on the console every 1s
123                           sos_paging_get_paddr !! 211  */
124                                                !! 212 static void stat_thread()
125   sos_x86_videomem_printf(6, 0,                !! 213 {
126                           SOS_X86_VIDEO_FG_YEL !! 214   while (1)
127                           "Transfer vpage 0x%x << 
128                           vpage_code,          << 
129                           sos_paging_get_paddr << 
130                           ppage_new,           << 
131                           (unsigned)vpage_tmp) << 
132                                                << 
133   /* Map the page somewhere (right after the k << 
134      to copy the code we are currently executi << 
135   sos_paging_map(ppage_new, vpage_tmp,         << 
136                  FALSE,                        << 
137                  SOS_VM_MAP_ATOMIC             << 
138                  | SOS_VM_MAP_PROT_READ        << 
139                  | SOS_VM_MAP_PROT_WRITE);     << 
140                                                << 
141   /* Ok, the new page is referenced by the map << 
142      reference to it */                        << 
143   sos_physmem_unref_physpage(ppage_new);       << 
144                                                << 
145   /* Copy the contents of the current page of  << 
146      mapping */                                << 
147   memcpy((void*)vpage_tmp,                     << 
148          (void*)vpage_code,                    << 
149          SOS_PAGE_SIZE);                       << 
150                                                << 
151   /* Transfer the mapping of the current page  << 
152   sos_paging_map(ppage_new, vpage_code,        << 
153                  FALSE,                        << 
154                  SOS_VM_MAP_ATOMIC             << 
155                  | SOS_VM_MAP_PROT_READ        << 
156                  | SOS_VM_MAP_PROT_WRITE);     << 
157                                                << 
158   /* Ok, here we are: we have changed the phys << 
159      code we are executing ;). However, this n << 
160      virtual addresses:                        << 
161      - vpage_tmp                               << 
162      - vpage_code                              << 
163      We can safely unmap it from sos_kernel_co << 
164      still keeping the vpage_code mapping */   << 
165   sos_paging_unmap(vpage_tmp);                 << 
166                                                << 
167   sos_x86_videomem_printf(7, 0,                << 
168                           SOS_X86_VIDEO_FG_YEL << 
169                           "Hello from the addr << 
170                           sos_paging_get_paddr << 
171                                                << 
172   sos_x86_videomem_printf(9, 0,                << 
173                           SOS_X86_VIDEO_FG_LTG << 
174                           "Provoking a page fa << 
175                                                << 
176   /*                                           << 
177    * Test 2: make sure the #PF handler works   << 
178    */                                          << 
179                                                << 
180   /* Scan part of the kernel up to a page faul << 
181      should occur on the first page unmapped a << 
182      which is exactly the page we temporarily  << 
183      (vpage_tmp) above to move the kernel code << 
184   for (i = vpage_code ; /* none */ ; i += SOS_ << 
185     {                                             215     {
186       unsigned *pint = (unsigned *)SOS_PAGE_AL !! 216       sos_ui32_t flags;
187       sos_bochs_printf("Test vaddr 0x%x : val= !! 217       sos_ui32_t load1, load5, load15;
188       sos_x86_videomem_printf(10, 0,           !! 218       char str1[11], str5[11], str15[11];
                                                   >> 219       struct sos_time t;
                                                   >> 220       t.sec = 1;
                                                   >> 221       t.nanosec = 0;
                                                   >> 222 
                                                   >> 223       sos_thread_sleep(& t);
                                                   >> 224 
                                                   >> 225       sos_disable_IRQs(flags);
                                                   >> 226 
                                                   >> 227       /* The IDLE task is EXcluded in the following computation */
                                                   >> 228       sos_load_get_sload(&load1, &load5, &load15);
                                                   >> 229       sos_load_to_string(str1, load1);
                                                   >> 230       sos_load_to_string(str5, load5);
                                                   >> 231       sos_load_to_string(str15, load15);
                                                   >> 232       sos_x86_videomem_printf(16, 34,
189                               SOS_X86_VIDEO_FG    233                               SOS_X86_VIDEO_FG_YELLOW | SOS_X86_VIDEO_BG_BLUE,
190                               "Test vaddr 0x%x !! 234                               "Kernel (- Idle): %s %s %s    ",
191                               (unsigned)pint); !! 235                               str1, str5, str15);
192       sos_bochs_printf("0x%x\n", *pint);       !! 236 
193       sos_x86_videomem_printf(10, 30,          !! 237       sos_load_get_uload(&load1, &load5, &load15);
                                                   >> 238       sos_load_to_string(str1, load1);
                                                   >> 239       sos_load_to_string(str5, load5);
                                                   >> 240       sos_load_to_string(str15, load15);
                                                   >> 241       sos_x86_videomem_printf(17, 34,
194                               SOS_X86_VIDEO_FG    242                               SOS_X86_VIDEO_FG_YELLOW | SOS_X86_VIDEO_BG_BLUE,
195                               "0x%x          " !! 243                               "User: %s %s %s        ",
                                                   >> 244                               str1, str5, str15);
                                                   >> 245 
                                                   >> 246       sos_load_get_uratio(&load1, &load5, &load15);
                                                   >> 247       sos_load_to_string(str1, load1);
                                                   >> 248       sos_load_to_string(str5, load5);
                                                   >> 249       sos_load_to_string(str15, load15);
                                                   >> 250       sos_x86_videomem_printf(18, 34,
                                                   >> 251                               SOS_X86_VIDEO_FG_YELLOW | SOS_X86_VIDEO_BG_BLUE,
                                                   >> 252                               "User CPU %%: %s %s %s        ",
                                                   >> 253                               str1, str5, str15);
                                                   >> 254 
                                                   >> 255       /* The IDLE task is INcluded in the following computation */
                                                   >> 256       sos_load_get_sratio(&load1, &load5, &load15);
                                                   >> 257       sos_load_to_string(str1, load1);
                                                   >> 258       sos_load_to_string(str5, load5);
                                                   >> 259       sos_load_to_string(str15, load15);
                                                   >> 260       sos_x86_videomem_printf(19, 34,
                                                   >> 261                               SOS_X86_VIDEO_FG_YELLOW | SOS_X86_VIDEO_BG_BLUE,
                                                   >> 262                               "Kernel CPU %% (+ Idle): %s %s %s    ",
                                                   >> 263                               str1, str5, str15);
                                                   >> 264       sos_restore_IRQs(flags);
                                                   >> 265     }
                                                   >> 266 }
                                                   >> 267 
                                                   >> 268 
                                                   >> 269 /* ======================================================================
                                                   >> 270  * Start the "init" (userland) process
                                                   >> 271  */
                                                   >> 272 static sos_ret_t start_init()
                                                   >> 273 {
                                                   >> 274   sos_ret_t retval;
                                                   >> 275   struct sos_umem_vmm_as *as_init;
                                                   >> 276   struct sos_process *proc_init;
                                                   >> 277   struct sos_thread *new_thr;
                                                   >> 278   sos_uaddr_t ustack, start_uaddr;
                                                   >> 279 
                                                   >> 280   /* Create the new process */
                                                   >> 281   proc_init = sos_process_create("init", FALSE);
                                                   >> 282   if (! proc_init)
                                                   >> 283     return -SOS_ENOMEM;
                                                   >> 284   as_init = sos_process_get_address_space(proc_init);
                                                   >> 285 
                                                   >> 286   /* Map the 'init' program in user space */
                                                   >> 287   start_uaddr = sos_binfmt_elf32_map(as_init, "init");
                                                   >> 288   if (0 == start_uaddr)
                                                   >> 289     {
                                                   >> 290       sos_process_unref(proc_init);
                                                   >> 291       return -SOS_ENOENT;
                                                   >> 292     }
                                                   >> 293      
                                                   >> 294   /* Allocate the user stack */
                                                   >> 295   ustack = (SOS_PAGING_TOP_USER_ADDRESS - SOS_DEFAULT_USER_STACK_SIZE) + 1;
                                                   >> 296   retval = sos_dev_zero_map(as_init, &ustack, SOS_DEFAULT_USER_STACK_SIZE,
                                                   >> 297                             SOS_VM_MAP_PROT_READ | SOS_VM_MAP_PROT_WRITE,
                                                   >> 298                             /* PRIVATE */ 0);
                                                   >> 299   if (SOS_OK != retval)
                                                   >> 300     {
                                                   >> 301       sos_bochs_printf("ici 2\n");
                                                   >> 302       sos_process_unref(proc_init);
                                                   >> 303       return -SOS_ENOMEM;
196     }                                             304     }
197                                                   305 
198   /* BAD ! Did not get the page fault... */    !! 306   /* Now create the user thread */
199   sos_x86_videomem_printf(20, 0,               !! 307   new_thr = sos_create_user_thread(NULL,
200                           SOS_X86_VIDEO_FG_LTR !! 308                                    proc_init,
201                           "We should have had  !! 309                                    start_uaddr,
202                           vpage_tmp);          !! 310                                    0, 0,
                                                   >> 311                                    ustack + SOS_DEFAULT_USER_STACK_SIZE - 4,
                                                   >> 312                                    SOS_SCHED_PRIO_TS_LOWEST);
                                                   >> 313   if (! new_thr)
                                                   >> 314     {
                                                   >> 315       sos_bochs_printf("ici 3\n");
                                                   >> 316       sos_process_unref(proc_init);
                                                   >> 317       return -SOS_ENOMEM;
                                                   >> 318     }
                                                   >> 319 
                                                   >> 320   sos_process_unref(proc_init);
                                                   >> 321   return SOS_OK;
203 }                                                 322 }
204                                                   323 
205 /* The C entry point of our operating system * !! 324 
                                                   >> 325 /* ======================================================================
                                                   >> 326  * The C entry point of our operating system
                                                   >> 327  */
206 void sos_main(unsigned long magic, unsigned lo    328 void sos_main(unsigned long magic, unsigned long addr)
207 {                                                 329 {
208   unsigned i;                                     330   unsigned i;
209   sos_paddr_t sos_kernel_core_base_paddr, sos_    331   sos_paddr_t sos_kernel_core_base_paddr, sos_kernel_core_top_paddr;
                                                   >> 332   struct sos_time tick_resolution;
210                                                   333 
211   /* Grub sends us a structure, called multibo    334   /* Grub sends us a structure, called multiboot_info_t with a lot of
212      precious informations about the system, s    335      precious informations about the system, see the multiboot
213      documentation for more information. */       336      documentation for more information. */
214   multiboot_info_t *mbi;                          337   multiboot_info_t *mbi;
215   mbi = (multiboot_info_t *) addr;                338   mbi = (multiboot_info_t *) addr;
216                                                   339 
217   /* Setup bochs and console, and clear the co    340   /* Setup bochs and console, and clear the console */
218   sos_bochs_setup();                              341   sos_bochs_setup();
219                                                   342 
220   sos_x86_videomem_setup();                       343   sos_x86_videomem_setup();
221   sos_x86_videomem_cls(SOS_X86_VIDEO_BG_BLUE);    344   sos_x86_videomem_cls(SOS_X86_VIDEO_BG_BLUE);
222                                                   345 
223   /* Greetings from SOS */                        346   /* Greetings from SOS */
224   if (magic == MULTIBOOT_BOOTLOADER_MAGIC)        347   if (magic == MULTIBOOT_BOOTLOADER_MAGIC)
225     /* Loaded with Grub */                        348     /* Loaded with Grub */
226     sos_x86_videomem_printf(1, 0,                 349     sos_x86_videomem_printf(1, 0,
227                             SOS_X86_VIDEO_FG_Y    350                             SOS_X86_VIDEO_FG_YELLOW | SOS_X86_VIDEO_BG_BLUE,
228                             "Welcome From GRUB    351                             "Welcome From GRUB to %s%c RAM is %dMB (upper mem = 0x%x kB)",
229                             "SOS", ',',        !! 352                             "SOS article 7.5", ',',
230                             (unsigned)(mbi->me    353                             (unsigned)(mbi->mem_upper >> 10) + 1,
231                             (unsigned)mbi->mem    354                             (unsigned)mbi->mem_upper);
232   else                                            355   else
233     /* Not loaded with grub */                    356     /* Not loaded with grub */
234     sos_x86_videomem_printf(1, 0,                 357     sos_x86_videomem_printf(1, 0,
235                             SOS_X86_VIDEO_FG_Y    358                             SOS_X86_VIDEO_FG_YELLOW | SOS_X86_VIDEO_BG_BLUE,
236                             "Welcome to SOS"); !! 359                             "Welcome to SOS article 7.5");
237                                                   360 
238   sos_bochs_putstring("Message in a bochs\n"); !! 361   sos_bochs_putstring("Message in a bochs: This is SOS article 7.5.\n");
239                                                   362 
240   /* Setup CPU segmentation and IRQ subsystem     363   /* Setup CPU segmentation and IRQ subsystem */
241   sos_gdt_setup();                             !! 364   sos_gdt_subsystem_setup();
242   sos_idt_setup();                             !! 365   sos_idt_subsystem_setup();
243                                                   366 
244   /* Setup SOS IRQs and exceptions subsystem *    367   /* Setup SOS IRQs and exceptions subsystem */
245   sos_exceptions_setup();                      !! 368   sos_exception_subsystem_setup();
246   sos_irq_setup();                             !! 369   sos_irq_subsystem_setup();
247                                                   370 
248   /* Configure the timer so as to raise the IR    371   /* Configure the timer so as to raise the IRQ0 at a 100Hz rate */
249   sos_i8254_set_frequency(100);                   372   sos_i8254_set_frequency(100);
250                                                   373 
                                                   >> 374   /* Setup the kernel time subsystem to get prepared to take the timer
                                                   >> 375      ticks into account */
                                                   >> 376   tick_resolution = (struct sos_time) { .sec=0, .nanosec=10000000UL };
                                                   >> 377   sos_time_subsysem_setup(& tick_resolution);
251                                                   378 
252   /* We need a multiboot-compliant boot loader    379   /* We need a multiboot-compliant boot loader to get the size of the RAM */
253   if (magic != MULTIBOOT_BOOTLOADER_MAGIC)        380   if (magic != MULTIBOOT_BOOTLOADER_MAGIC)
254     {                                             381     {
255       sos_x86_videomem_putstring(20, 0,           382       sos_x86_videomem_putstring(20, 0,
256                                  SOS_X86_VIDEO    383                                  SOS_X86_VIDEO_FG_LTRED
257                                    | SOS_X86_V    384                                    | SOS_X86_VIDEO_BG_BLUE
258                                    | SOS_X86_V    385                                    | SOS_X86_VIDEO_FG_BLINKING,
259                                  "I'm not load    386                                  "I'm not loaded with Grub !");
260       /* STOP ! */                                387       /* STOP ! */
261       for (;;)                                    388       for (;;)
262         continue;                                 389         continue;
263     }                                             390     }
264                                                   391 
                                                   >> 392   /*
                                                   >> 393    * Some interrupt handlers
                                                   >> 394    */
                                                   >> 395 
265   /* Binding some HW interrupts and exceptions    396   /* Binding some HW interrupts and exceptions to software routines */
266   sos_irq_set_routine(SOS_IRQ_TIMER,              397   sos_irq_set_routine(SOS_IRQ_TIMER,
267                             clk_it);           !! 398                       clk_it);
268   /* Enabling the HW interrupts here, this wil !! 399 
269      interrupt call our clk_it handler */      !! 400   /*
270   asm volatile ("sti\n");                      !! 401    * Setup physical memory management
                                                   >> 402    */
                                                   >> 403 
271   /* Multiboot says: "The value returned for u    404   /* Multiboot says: "The value returned for upper memory is maximally
272      the address of the first upper memory hol    405      the address of the first upper memory hole minus 1 megabyte.". It
273      also adds: "It is not guaranteed to be th    406      also adds: "It is not guaranteed to be this value." aka "YMMV" ;) */
274   sos_physmem_setup((mbi->mem_upper<<10) + (1< !! 407   sos_physmem_subsystem_setup((mbi->mem_upper<<10) + (1<<20),
275                     & sos_kernel_core_base_pad !! 408                               & sos_kernel_core_base_paddr,
276                     & sos_kernel_core_top_padd !! 409                               & sos_kernel_core_top_paddr);
277                                                   410   
278   /*                                              411   /*
279    * Switch to paged-memory mode                  412    * Switch to paged-memory mode
280    */                                             413    */
281                                                   414 
282   /* Disabling interrupts should seem more cor    415   /* Disabling interrupts should seem more correct, but it's not really
283      necessary at this stage */                   416      necessary at this stage */
284   if (sos_paging_setup(sos_kernel_core_base_pa !! 417   SOS_ASSERT_FATAL(SOS_OK ==
285                        sos_kernel_core_top_pad !! 418                    sos_paging_subsystem_setup(sos_kernel_core_base_paddr,
286     sos_bochs_printf("Could not setup paged me !! 419                                               sos_kernel_core_top_paddr));
287   sos_x86_videomem_printf(2, 0,                !! 420   
288                           SOS_X86_VIDEO_FG_YEL !! 421   /* Bind the page fault exception */
289                           "Paged-memory mode i !! 422   sos_exception_set_routine(SOS_EXCEPT_PAGE_FAULT,
290                                                !! 423                             pgflt_ex);
291   test_paging(sos_kernel_core_top_paddr);      !! 424 
292                                                !! 425   /*
293   /* An operatig system never ends */          !! 426    * Setup kernel virtual memory allocator
294   for (;;)                                     !! 427    */
295     continue;                                  !! 428 
                                                   >> 429   if (sos_kmem_vmm_subsystem_setup(sos_kernel_core_base_paddr,
                                                   >> 430                                    sos_kernel_core_top_paddr,
                                                   >> 431                                    bootstrap_stack_bottom,
                                                   >> 432                                    bootstrap_stack_bottom
                                                   >> 433                                    + bootstrap_stack_size))
                                                   >> 434     sos_bochs_printf("Could not setup the Kernel virtual space allocator\n");
                                                   >> 435 
                                                   >> 436   if (sos_kmalloc_subsystem_setup())
                                                   >> 437     sos_bochs_printf("Could not setup the Kmalloc subsystem\n");
                                                   >> 438 
                                                   >> 439   /*
                                                   >> 440    * Initialize the MMU context subsystem
                                                   >> 441    */
                                                   >> 442   sos_mm_context_subsystem_setup();
                                                   >> 443 
                                                   >> 444   /*
                                                   >> 445    * Initialize the CPU context subsystem
                                                   >> 446    */
                                                   >> 447   sos_cpu_context_subsystem_setup();
296                                                   448 
297   return;                                      !! 449   /*
                                                   >> 450    * Bind the syscall handler to its software interrupt handler
                                                   >> 451    */
                                                   >> 452   sos_swintr_subsystem_setup();
                                                   >> 453 
                                                   >> 454 
                                                   >> 455   /*
                                                   >> 456    * Initialize the Kernel thread and scheduler subsystems
                                                   >> 457    */
                                                   >> 458   
                                                   >> 459   /* Initialize kernel thread subsystem */
                                                   >> 460   sos_thread_subsystem_setup(bootstrap_stack_bottom,
                                                   >> 461                              bootstrap_stack_size);
                                                   >> 462 
                                                   >> 463   /* Initialize the scheduler */
                                                   >> 464   sos_sched_subsystem_setup();
                                                   >> 465 
                                                   >> 466   /* Declare the IDLE thread */
                                                   >> 467   SOS_ASSERT_FATAL(sos_create_kernel_thread("idle", idle_thread, NULL,
                                                   >> 468                                             SOS_SCHED_PRIO_TS_LOWEST) != NULL);
                                                   >> 469 
                                                   >> 470   /* Prepare the stats subsystem */
                                                   >> 471   sos_load_subsystem_setup();
                                                   >> 472 
                                                   >> 473   /* Declare a thread that prints some stats */
                                                   >> 474   SOS_ASSERT_FATAL(sos_create_kernel_thread("stat_thread", stat_thread,
                                                   >> 475                                             NULL,
                                                   >> 476                                             SOS_SCHED_PRIO_TS_LOWEST) != NULL);
                                                   >> 477 
                                                   >> 478 
                                                   >> 479   /*
                                                   >> 480    * Initialise user address space management subsystem
                                                   >> 481    */
                                                   >> 482   sos_umem_vmm_subsystem_setup();
                                                   >> 483   sos_dev_zero_subsystem_setup();
                                                   >> 484 
                                                   >> 485   /*
                                                   >> 486    * Initialize process stuff
                                                   >> 487    */
                                                   >> 488   sos_process_subsystem_setup();
                                                   >> 489 
                                                   >> 490 
                                                   >> 491   /* Enabling the HW interrupts here, this will make the timer HW
                                                   >> 492      interrupt call the scheduler */
                                                   >> 493   asm volatile ("sti\n");
                                                   >> 494 
                                                   >> 495   /* Start the 'init' process, which in turns launches the other
                                                   >> 496      programs */
                                                   >> 497   start_init();
                                                   >> 498 
                                                   >> 499   /*
                                                   >> 500    * We can safely exit from this function now, for there is already
                                                   >> 501    * an idle Kernel thread ready to make the CPU busy working...
                                                   >> 502    *
                                                   >> 503    * However, we must EXPLICITELY call sos_thread_exit() because a
                                                   >> 504    * simple "return" will return nowhere ! Actually this first thread
                                                   >> 505    * was initialized by the Grub bootstrap stage, at a time when the
                                                   >> 506    * word "thread" did not exist. This means that the stack was not
                                                   >> 507    * setup in order for a return here to call sos_thread_exit()
                                                   >> 508    * automagically. Hence we must call it manually. This is the ONLY
                                                   >> 509    * kernel thread where we must do this manually.
                                                   >> 510    */
                                                   >> 511   sos_bochs_printf("Bye from primary thread !\n");
                                                   >> 512   sos_thread_exit();
                                                   >> 513   SOS_FATAL_ERROR("No trespassing !");
298 }                                                 514 }
                                                      

source navigation ] diff markup ] identifier search ] general search ]