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001 /* Copyright (C) 2004 David Decotigny 001 /* Copyright (C) 2004 David Decotigny 002 Copyright (C) 2000 The KOS Team 002 Copyright (C) 2000 The KOS Team 003 003 004 This program is free software; you can redi 004 This program is free software; you can redistribute it and/or 005 modify it under the terms of the GNU Genera 005 modify it under the terms of the GNU General Public License 006 as published by the Free Software Foundatio 006 as published by the Free Software Foundation; either version 2 007 of the License, or (at your option) any lat 007 of the License, or (at your option) any later version. 008 008 009 This program is distributed in the hope tha 009 This program is distributed in the hope that it will be useful, 010 but WITHOUT ANY WARRANTY; without even the 010 but WITHOUT ANY WARRANTY; without even the implied warranty of 011 MERCHANTABILITY or FITNESS FOR A PARTICULAR 011 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 012 GNU General Public License for more details 012 GNU General Public License for more details. 013 013 014 You should have received a copy of the GNU 014 You should have received a copy of the GNU General Public License 015 along with this program; if not, write to t 015 along with this program; if not, write to the Free Software 016 Foundation, Inc., 59 Temple Place - Suite 3 016 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, 017 USA. 017 USA. 018 */ 018 */ 019 #include <sos/list.h> 019 #include <sos/list.h> 020 #include <sos/macros.h> 020 #include <sos/macros.h> 021 #include <sos/assert.h> 021 #include <sos/assert.h> 022 #include <sos/klibc.h> 022 #include <sos/klibc.h> 023 023 024 #include "physmem.h" 024 #include "physmem.h" 025 025 026 /** A descriptor for a physical page in SOS */ 026 /** A descriptor for a physical page in SOS */ 027 struct physical_page_descr 027 struct physical_page_descr 028 { 028 { 029 /** The physical base address for the page * 029 /** The physical base address for the page */ 030 sos_paddr_t paddr; 030 sos_paddr_t paddr; 031 031 032 /** The reference count for this physical pa 032 /** The reference count for this physical page. > 0 means that the 033 page is in the nonfree list. */ !! 033 page is in the used list. */ 034 sos_count_t ref_cnt; 034 sos_count_t ref_cnt; 035 035 036 /** << 037 * An additional counter for user-defined us << 038 * counter is up to the user, however a simp << 039 * - it can only be incremented/decremente << 040 * - when it reaches 0, no automatic actio << 041 * The first rule means in particular that a << 042 * count reaches 0 (=> will be freed) cannot << 043 * value > 0 ! The system will be HALTED if << 044 */ << 045 sos_count_t occupation_cnt; << 046 << 047 << 048 /** Some data associated with the page when 036 /** Some data associated with the page when it is mapped in kernel space */ 049 struct sos_kmem_range *kernel_range; 037 struct sos_kmem_range *kernel_range; 050 038 051 /** The other pages on the list (nonfree, fr !! 039 /** The other pages on the list (used, free) */ 052 struct physical_page_descr *prev, *next; 040 struct physical_page_descr *prev, *next; 053 }; 041 }; 054 042 055 /** These are some markers present in the exec 043 /** These are some markers present in the executable file (see sos.lds) */ 056 extern char __b_kernel, __e_kernel; 044 extern char __b_kernel, __e_kernel; 057 045 058 /** The array of ppage descriptors will be loc 046 /** The array of ppage descriptors will be located at this address */ 059 #define PAGE_DESCR_ARRAY_ADDR \ 047 #define PAGE_DESCR_ARRAY_ADDR \ 060 SOS_PAGE_ALIGN_SUP((sos_paddr_t) (& __e_kern 048 SOS_PAGE_ALIGN_SUP((sos_paddr_t) (& __e_kernel)) 061 static struct physical_page_descr * physical_p 049 static struct physical_page_descr * physical_page_descr_array; 062 050 063 /** The list of physical pages currently avail 051 /** The list of physical pages currently available */ 064 static struct physical_page_descr *free_ppage; 052 static struct physical_page_descr *free_ppage; 065 053 066 /** The list of physical pages currently alloc !! 054 /** The list of physical pages currently in use */ 067 static struct physical_page_descr *nonfree_ppa !! 055 static struct physical_page_descr *used_ppage; 068 056 069 /** We will store here the interval of valid p 057 /** We will store here the interval of valid physical addresses */ 070 static sos_paddr_t physmem_base, physmem_top; 058 static sos_paddr_t physmem_base, physmem_top; 071 059 072 /** We store the number of pages nonfree/free !! 060 /** We store the number of pages used/free */ 073 static sos_count_t physmem_total_pages, physme !! 061 static sos_count_t physmem_total_pages, physmem_used_pages; 074 062 075 sos_ret_t sos_physmem_subsystem_setup(sos_size 063 sos_ret_t sos_physmem_subsystem_setup(sos_size_t ram_size, 076 /* out * 064 /* out */sos_paddr_t *kernel_core_base, 077 /* out * 065 /* out */sos_paddr_t *kernel_core_top) 078 { 066 { 079 /* The iterator over the page descriptors */ 067 /* The iterator over the page descriptors */ 080 struct physical_page_descr *ppage_descr; 068 struct physical_page_descr *ppage_descr; 081 069 082 /* The iterator over the physical addresses 070 /* The iterator over the physical addresses */ 083 sos_paddr_t ppage_addr; 071 sos_paddr_t ppage_addr; 084 072 085 /* Make sure ram size is aligned on a page b 073 /* Make sure ram size is aligned on a page boundary */ 086 ram_size = SOS_PAGE_ALIGN_INF(ram_size);/* Y 074 ram_size = SOS_PAGE_ALIGN_INF(ram_size);/* Yes, we may lose at most a page */ 087 075 088 /* Reset the nonfree/free page lists before !! 076 /* Reset the used/free page lists before building them */ 089 free_ppage = nonfree_ppage = NULL; !! 077 free_ppage = used_ppage = NULL; 090 physmem_total_pages = physmem_nonfree_pages !! 078 physmem_total_pages = physmem_used_pages = 0; 091 079 092 /* Make sure that there is enough memory to 080 /* Make sure that there is enough memory to store the array of page 093 descriptors */ 081 descriptors */ 094 *kernel_core_base = SOS_PAGE_ALIGN_INF((sos_ 082 *kernel_core_base = SOS_PAGE_ALIGN_INF((sos_paddr_t)(& __b_kernel)); 095 *kernel_core_top 083 *kernel_core_top 096 = PAGE_DESCR_ARRAY_ADDR 084 = PAGE_DESCR_ARRAY_ADDR 097 + SOS_PAGE_ALIGN_SUP( (ram_size >> SOS_P 085 + SOS_PAGE_ALIGN_SUP( (ram_size >> SOS_PAGE_SHIFT) 098 * sizeof(struct ph 086 * sizeof(struct physical_page_descr)); 099 if (*kernel_core_top > ram_size) 087 if (*kernel_core_top > ram_size) 100 return -SOS_ENOMEM; 088 return -SOS_ENOMEM; 101 089 102 /* Page 0-4kB is not available in order to r 090 /* Page 0-4kB is not available in order to return address 0 as a 103 means to signal "no page available" */ 091 means to signal "no page available" */ 104 physmem_base = SOS_PAGE_SIZE; 092 physmem_base = SOS_PAGE_SIZE; 105 physmem_top = ram_size; 093 physmem_top = ram_size; 106 094 107 /* Setup the page descriptor arrray */ 095 /* Setup the page descriptor arrray */ 108 physical_page_descr_array 096 physical_page_descr_array 109 = (struct physical_page_descr*)PAGE_DESCR_ 097 = (struct physical_page_descr*)PAGE_DESCR_ARRAY_ADDR; 110 098 111 /* Scan the list of physical pages */ 099 /* Scan the list of physical pages */ 112 for (ppage_addr = 0, 100 for (ppage_addr = 0, 113 ppage_descr = physical_page_descr_arr 101 ppage_descr = physical_page_descr_array ; 114 ppage_addr < physmem_top ; 102 ppage_addr < physmem_top ; 115 ppage_addr += SOS_PAGE_SIZE, 103 ppage_addr += SOS_PAGE_SIZE, 116 ppage_descr ++) 104 ppage_descr ++) 117 { 105 { 118 enum { PPAGE_MARK_RESERVED, PPAGE_MARK_F 106 enum { PPAGE_MARK_RESERVED, PPAGE_MARK_FREE, 119 PPAGE_MARK_KERNEL, PPAGE_MARK_HWM 107 PPAGE_MARK_KERNEL, PPAGE_MARK_HWMAP } todo; 120 108 121 memset(ppage_descr, 0x0, sizeof(struct p 109 memset(ppage_descr, 0x0, sizeof(struct physical_page_descr)); 122 110 123 /* Init the page descriptor for this pag 111 /* Init the page descriptor for this page */ 124 ppage_descr->paddr = ppage_addr; 112 ppage_descr->paddr = ppage_addr; 125 113 126 /* Reserved : 0 ... base */ 114 /* Reserved : 0 ... base */ 127 if (ppage_addr < physmem_base) 115 if (ppage_addr < physmem_base) 128 todo = PPAGE_MARK_RESERVED; 116 todo = PPAGE_MARK_RESERVED; 129 117 130 /* Free : base ... BIOS */ 118 /* Free : base ... BIOS */ 131 else if ((ppage_addr >= physmem_base) 119 else if ((ppage_addr >= physmem_base) 132 && (ppage_addr < BIOS_N_VIDEO_S 120 && (ppage_addr < BIOS_N_VIDEO_START)) 133 todo = PPAGE_MARK_FREE; 121 todo = PPAGE_MARK_FREE; 134 122 135 /* Used : BIOS */ 123 /* Used : BIOS */ 136 else if ((ppage_addr >= BIOS_N_VIDEO_STA 124 else if ((ppage_addr >= BIOS_N_VIDEO_START) 137 && (ppage_addr < BIOS_N_VIDEO_E 125 && (ppage_addr < BIOS_N_VIDEO_END)) 138 todo = PPAGE_MARK_HWMAP; 126 todo = PPAGE_MARK_HWMAP; 139 127 140 /* Free : BIOS ... kernel */ 128 /* Free : BIOS ... kernel */ 141 else if ((ppage_addr >= BIOS_N_VIDEO_END 129 else if ((ppage_addr >= BIOS_N_VIDEO_END) 142 && (ppage_addr < (sos_paddr_t) 130 && (ppage_addr < (sos_paddr_t) (& __b_kernel))) 143 todo = PPAGE_MARK_FREE; 131 todo = PPAGE_MARK_FREE; 144 132 145 /* Used : Kernel code/data/bss + physcal 133 /* Used : Kernel code/data/bss + physcal page descr array */ 146 else if ((ppage_addr >= *kernel_core_bas 134 else if ((ppage_addr >= *kernel_core_base) 147 && (ppage_addr < *kernel_core_ 135 && (ppage_addr < *kernel_core_top)) 148 todo = PPAGE_MARK_KERNEL; 136 todo = PPAGE_MARK_KERNEL; 149 137 150 /* Free : first page of descr ... end of 138 /* Free : first page of descr ... end of RAM */ 151 else 139 else 152 todo = PPAGE_MARK_FREE; 140 todo = PPAGE_MARK_FREE; 153 141 154 /* Actually does the insertion in the no !! 142 /* Actually does the insertion in the used/free page lists */ 155 physmem_total_pages ++; 143 physmem_total_pages ++; 156 switch (todo) 144 switch (todo) 157 { 145 { 158 case PPAGE_MARK_FREE: 146 case PPAGE_MARK_FREE: 159 ppage_descr->ref_cnt = 0; 147 ppage_descr->ref_cnt = 0; 160 list_add_head(free_ppage, ppage_desc 148 list_add_head(free_ppage, ppage_descr); 161 break; 149 break; 162 150 163 case PPAGE_MARK_KERNEL: 151 case PPAGE_MARK_KERNEL: 164 case PPAGE_MARK_HWMAP: 152 case PPAGE_MARK_HWMAP: 165 ppage_descr->ref_cnt = 1; 153 ppage_descr->ref_cnt = 1; 166 list_add_head(nonfree_ppage, ppage_d !! 154 list_add_head(used_ppage, ppage_descr); 167 physmem_nonfree_pages ++; !! 155 physmem_used_pages ++; 168 break; 156 break; 169 157 170 default: 158 default: 171 /* Reserved page: nop */ 159 /* Reserved page: nop */ 172 break; 160 break; 173 } 161 } 174 } 162 } 175 163 176 return SOS_OK; 164 return SOS_OK; 177 } 165 } 178 166 179 167 180 sos_paddr_t sos_physmem_ref_physpage_new(sos_b 168 sos_paddr_t sos_physmem_ref_physpage_new(sos_bool_t can_block) 181 { 169 { 182 struct physical_page_descr *ppage_descr; 170 struct physical_page_descr *ppage_descr; 183 171 184 if (! free_ppage) 172 if (! free_ppage) 185 return (sos_paddr_t)NULL; 173 return (sos_paddr_t)NULL; 186 174 187 /* Retrieve a page in the free list */ 175 /* Retrieve a page in the free list */ 188 ppage_descr = list_pop_head(free_ppage); 176 ppage_descr = list_pop_head(free_ppage); 189 177 190 /* The page is assumed not to be already in !! 178 /* The page is assumed not to be already used */ 191 SOS_ASSERT_FATAL(ppage_descr->ref_cnt == 0); 179 SOS_ASSERT_FATAL(ppage_descr->ref_cnt == 0); 192 180 193 /* Mark the page as nonfree (this of course !! 181 /* Mark the page as used (this of course sets the ref count to 1) */ 194 ppage_descr->ref_cnt ++; 182 ppage_descr->ref_cnt ++; 195 183 196 /* The page descriptor should be unmodified !! 184 /* No associated kernel range by default */ 197 deallocation. Otherwise this means that s !! 185 ppage_descr->kernel_range = NULL; 198 overwrote the page descriptor table conte << 199 SOS_ASSERT_FATAL(ppage_descr->occupation_cnt << 200 SOS_ASSERT_FATAL(ppage_descr->kernel_range = << 201 186 202 /* Put the page in the nonfree list */ !! 187 /* Put the page in the used list */ 203 list_add_tail(nonfree_ppage, ppage_descr); !! 188 list_add_tail(used_ppage, ppage_descr); 204 physmem_nonfree_pages ++; !! 189 physmem_used_pages ++; 205 190 206 return ppage_descr->paddr; 191 return ppage_descr->paddr; 207 } 192 } 208 193 209 194 210 /** 195 /** 211 * Helper function to get the physical page de 196 * Helper function to get the physical page descriptor for the given 212 * physical page address. 197 * physical page address. 213 * 198 * 214 * @return NULL when out-of-bounds or non-page 199 * @return NULL when out-of-bounds or non-page-aligned 215 */ 200 */ 216 inline static struct physical_page_descr * 201 inline static struct physical_page_descr * 217 get_page_descr_at_paddr(sos_paddr_t ppage_padd 202 get_page_descr_at_paddr(sos_paddr_t ppage_paddr) 218 { 203 { 219 /* Don't handle non-page-aligned addresses * 204 /* Don't handle non-page-aligned addresses */ 220 if (ppage_paddr & SOS_PAGE_MASK) 205 if (ppage_paddr & SOS_PAGE_MASK) 221 return NULL; 206 return NULL; 222 207 223 /* Don't support out-of-bounds requests */ 208 /* Don't support out-of-bounds requests */ 224 if ((ppage_paddr < physmem_base) || (ppage_p 209 if ((ppage_paddr < physmem_base) || (ppage_paddr >= physmem_top)) 225 return NULL; 210 return NULL; 226 211 227 return physical_page_descr_array + (ppage_pa 212 return physical_page_descr_array + (ppage_paddr >> SOS_PAGE_SHIFT); 228 } 213 } 229 214 230 215 231 sos_ret_t sos_physmem_ref_physpage_at(sos_padd 216 sos_ret_t sos_physmem_ref_physpage_at(sos_paddr_t ppage_paddr) 232 { 217 { 233 struct physical_page_descr *ppage_descr 218 struct physical_page_descr *ppage_descr 234 = get_page_descr_at_paddr(ppage_paddr); 219 = get_page_descr_at_paddr(ppage_paddr); 235 220 236 if (! ppage_descr) 221 if (! ppage_descr) 237 return -SOS_EINVAL; 222 return -SOS_EINVAL; 238 223 239 /* Increment the reference count for the pag 224 /* Increment the reference count for the page */ 240 ppage_descr->ref_cnt ++; 225 ppage_descr->ref_cnt ++; 241 226 242 /* If the page is newly referenced (ie we ar 227 /* If the page is newly referenced (ie we are the only owners of the 243 page => ref cnt == 1), transfer it in the !! 228 page => ref cnt == 1), transfer it in the used pages list */ 244 if (ppage_descr->ref_cnt == 1) 229 if (ppage_descr->ref_cnt == 1) 245 { 230 { 246 /* The page descriptor should be unmodif << 247 deallocation. Otherwise this means th << 248 overwrote the page descriptor table c << 249 SOS_ASSERT_FATAL(ppage_descr->occupation << 250 SOS_ASSERT_FATAL(ppage_descr->kernel_ran << 251 << 252 list_delete(free_ppage, ppage_descr); 231 list_delete(free_ppage, ppage_descr); 253 list_add_tail(nonfree_ppage, ppage_descr !! 232 254 physmem_nonfree_pages ++; !! 233 /* No associated kernel range by default */ >> 234 ppage_descr->kernel_range = NULL; >> 235 >> 236 list_add_tail(used_ppage, ppage_descr); >> 237 physmem_used_pages ++; 255 238 256 /* The page is newly referenced */ 239 /* The page is newly referenced */ 257 return FALSE; 240 return FALSE; 258 } 241 } 259 !! 242 260 /* The page was already referenced by someon 243 /* The page was already referenced by someone */ 261 return TRUE; 244 return TRUE; 262 } 245 } 263 246 264 247 265 sos_ret_t 248 sos_ret_t 266 sos_physmem_unref_physpage(sos_paddr_t ppage_p 249 sos_physmem_unref_physpage(sos_paddr_t ppage_paddr) 267 { 250 { 268 /* By default the return value indicates tha 251 /* By default the return value indicates that the page is still 269 used */ 252 used */ 270 sos_ret_t retval = FALSE; 253 sos_ret_t retval = FALSE; 271 254 272 struct physical_page_descr *ppage_descr 255 struct physical_page_descr *ppage_descr 273 = get_page_descr_at_paddr(ppage_paddr); 256 = get_page_descr_at_paddr(ppage_paddr); 274 257 275 if (! ppage_descr) 258 if (! ppage_descr) 276 return -SOS_EINVAL; 259 return -SOS_EINVAL; 277 260 278 /* Don't do anything if the page is not in t !! 261 /* Don't do anything if the page is not in the used list */ 279 if (ppage_descr->ref_cnt <= 0) 262 if (ppage_descr->ref_cnt <= 0) 280 return -SOS_EINVAL; 263 return -SOS_EINVAL; 281 264 282 /* Unreference the page, and, when no mappin 265 /* Unreference the page, and, when no mapping is active anymore, put 283 the page in the free list */ 266 the page in the free list */ 284 ppage_descr->ref_cnt--; 267 ppage_descr->ref_cnt--; 285 if (ppage_descr->ref_cnt == 0) !! 268 if (ppage_descr->ref_cnt <= 0) 286 { 269 { 287 /* Make sure that the occupation counter << 288 SOS_ASSERT_FATAL(ppage_descr->occupation << 289 << 290 /* Reset associated kernel range */ 270 /* Reset associated kernel range */ 291 ppage_descr->kernel_range = NULL; 271 ppage_descr->kernel_range = NULL; 292 272 293 /* Transfer the page, considered NON-FRE !! 273 /* Transfer the page, considered USED, to the free list */ 294 list_delete(nonfree_ppage, ppage_descr); !! 274 list_delete(used_ppage, ppage_descr); 295 physmem_nonfree_pages --; !! 275 physmem_used_pages --; 296 << 297 list_add_head(free_ppage, ppage_descr); 276 list_add_head(free_ppage, ppage_descr); 298 277 299 /* Indicate that the page is now unrefer 278 /* Indicate that the page is now unreferenced */ 300 retval = TRUE; 279 retval = TRUE; 301 } 280 } 302 281 303 /* The page was already referenced by someon << 304 return retval; 282 return retval; 305 } 283 } 306 284 307 285 308 sos_ret_t sos_physmem_get_physpage_refcount(so << 309 { << 310 struct physical_page_descr *ppage_descr << 311 = get_page_descr_at_paddr(ppage_paddr); << 312 << 313 if (! ppage_descr) << 314 return -SOS_EINVAL; << 315 << 316 return ppage_descr->ref_cnt; << 317 } << 318 << 319 << 320 sos_ret_t sos_physmem_inc_physpage_occupation( << 321 { << 322 struct physical_page_descr *ppage_descr << 323 = get_page_descr_at_paddr(ppage_paddr); << 324 << 325 if (! ppage_descr) << 326 return -SOS_EINVAL; << 327 << 328 /* Don't do anything if the page is not in t << 329 SOS_ASSERT_FATAL(ppage_descr->ref_cnt > 0); << 330 << 331 ppage_descr->occupation_cnt ++; << 332 return (ppage_descr->occupation_cnt > 1); << 333 } << 334 << 335 << 336 sos_ret_t sos_physmem_dec_physpage_occupation( << 337 { << 338 struct physical_page_descr *ppage_descr << 339 = get_page_descr_at_paddr(ppage_paddr); << 340 << 341 if (! ppage_descr) << 342 return -SOS_EINVAL; << 343 << 344 /* Don't do anything if the page is not in t << 345 SOS_ASSERT_FATAL(ppage_descr->ref_cnt > 0); << 346 SOS_ASSERT_FATAL(ppage_descr->occupation_cnt << 347 << 348 ppage_descr->occupation_cnt --; << 349 return (ppage_descr->occupation_cnt == 0); << 350 } << 351 << 352 << 353 struct sos_kmem_range* sos_physmem_get_kmem_ra 286 struct sos_kmem_range* sos_physmem_get_kmem_range(sos_paddr_t ppage_paddr) 354 { 287 { 355 struct physical_page_descr *ppage_descr 288 struct physical_page_descr *ppage_descr 356 = get_page_descr_at_paddr(ppage_paddr); 289 = get_page_descr_at_paddr(ppage_paddr); 357 290 358 if (! ppage_descr) 291 if (! ppage_descr) 359 return NULL; 292 return NULL; 360 293 361 return ppage_descr->kernel_range; 294 return ppage_descr->kernel_range; 362 } 295 } 363 296 364 297 365 sos_ret_t sos_physmem_set_kmem_range(sos_paddr 298 sos_ret_t sos_physmem_set_kmem_range(sos_paddr_t ppage_paddr, 366 struct so 299 struct sos_kmem_range *range) 367 { 300 { 368 struct physical_page_descr *ppage_descr 301 struct physical_page_descr *ppage_descr 369 = get_page_descr_at_paddr(ppage_paddr); 302 = get_page_descr_at_paddr(ppage_paddr); 370 303 371 if (! ppage_descr) 304 if (! ppage_descr) 372 return -SOS_EINVAL; 305 return -SOS_EINVAL; 373 306 374 ppage_descr->kernel_range = range; 307 ppage_descr->kernel_range = range; 375 return SOS_OK; 308 return SOS_OK; 376 } 309 } 377 310 378 sos_ret_t sos_physmem_get_state(/* out */sos_c 311 sos_ret_t sos_physmem_get_state(/* out */sos_count_t *total_ppages, 379 /* out */sos_c !! 312 /* out */sos_count_t *used_ppages) 380 { 313 { 381 if (total_ppages) 314 if (total_ppages) 382 *total_ppages = physmem_total_pages; 315 *total_ppages = physmem_total_pages; 383 if (nonfree_ppages) !! 316 if (used_ppages) 384 *nonfree_ppages = physmem_nonfree_pages; !! 317 *used_ppages = physmem_used_pages; 385 return SOS_OK; 318 return SOS_OK; 386 } 319 } 387 <<
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