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001 /* Copyright (C) 2004 David Decotigny 001 /* Copyright (C) 2004 David Decotigny 002 Copyright (C) 2000 The KOS Team << 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 #include <sos/list.h> 018 #include <sos/list.h> 020 #include <sos/macros.h> 019 #include <sos/macros.h> 021 #include <sos/assert.h> 020 #include <sos/assert.h> 022 #include <sos/klibc.h> 021 #include <sos/klibc.h> 023 022 024 #include "physmem.h" 023 #include "physmem.h" 025 024 026 /** A descriptor for a physical page in SOS */ 025 /** A descriptor for a physical page in SOS */ 027 struct physical_page_descr 026 struct physical_page_descr 028 { 027 { 029 /** The physical base address for the page * 028 /** The physical base address for the page */ 030 sos_paddr_t paddr; 029 sos_paddr_t paddr; 031 030 032 /** The reference count for this physical pa 031 /** The reference count for this physical page. > 0 means that the 033 page is in the used list. */ 032 page is in the used list. */ 034 sos_count_t ref_cnt; 033 sos_count_t ref_cnt; 035 034 036 /** Some data associated with the page when << 037 struct sos_kmem_range *kernel_range; << 038 << 039 /** The other pages on the list (used, free) 035 /** The other pages on the list (used, free) */ 040 struct physical_page_descr *prev, *next; 036 struct physical_page_descr *prev, *next; 041 }; 037 }; 042 038 043 /** These are some markers present in the exec 039 /** These are some markers present in the executable file (see sos.lds) */ 044 extern char __b_kernel, __e_kernel; 040 extern char __b_kernel, __e_kernel; 045 041 046 /** The array of ppage descriptors will be loc 042 /** The array of ppage descriptors will be located at this address */ 047 #define PAGE_DESCR_ARRAY_ADDR \ 043 #define PAGE_DESCR_ARRAY_ADDR \ 048 SOS_PAGE_ALIGN_SUP((sos_paddr_t) (& __e_kern 044 SOS_PAGE_ALIGN_SUP((sos_paddr_t) (& __e_kernel)) 049 static struct physical_page_descr * physical_p 045 static struct physical_page_descr * physical_page_descr_array; 050 046 051 /** The list of physical pages currently avail 047 /** The list of physical pages currently available */ 052 static struct physical_page_descr *free_ppage; 048 static struct physical_page_descr *free_ppage; 053 049 054 /** The list of physical pages currently in us 050 /** The list of physical pages currently in use */ 055 static struct physical_page_descr *used_ppage; 051 static struct physical_page_descr *used_ppage; 056 052 057 /** We will store here the interval of valid p 053 /** We will store here the interval of valid physical addresses */ 058 static sos_paddr_t physmem_base, physmem_top; 054 static sos_paddr_t physmem_base, physmem_top; 059 055 060 /** We store the number of pages used/free */ 056 /** We store the number of pages used/free */ 061 static sos_count_t physmem_total_pages, physme 057 static sos_count_t physmem_total_pages, physmem_used_pages; 062 058 063 sos_ret_t sos_physmem_subsystem_setup(sos_size !! 059 sos_ret_t sos_physmem_setup(sos_size_t ram_size, 064 /* out * !! 060 /* out */sos_paddr_t *kernel_core_base, 065 /* out * !! 061 /* out */sos_paddr_t *kernel_core_top) 066 { 062 { 067 /* The iterator over the page descriptors */ 063 /* The iterator over the page descriptors */ 068 struct physical_page_descr *ppage_descr; 064 struct physical_page_descr *ppage_descr; 069 065 070 /* The iterator over the physical addresses 066 /* The iterator over the physical addresses */ 071 sos_paddr_t ppage_addr; 067 sos_paddr_t ppage_addr; 072 068 073 /* Make sure ram size is aligned on a page b 069 /* Make sure ram size is aligned on a page boundary */ 074 ram_size = SOS_PAGE_ALIGN_INF(ram_size);/* Y 070 ram_size = SOS_PAGE_ALIGN_INF(ram_size);/* Yes, we may lose at most a page */ 075 071 076 /* Reset the used/free page lists before bui 072 /* Reset the used/free page lists before building them */ 077 free_ppage = used_ppage = NULL; 073 free_ppage = used_ppage = NULL; 078 physmem_total_pages = physmem_used_pages = 0 074 physmem_total_pages = physmem_used_pages = 0; 079 075 080 /* Make sure that there is enough memory to 076 /* Make sure that there is enough memory to store the array of page 081 descriptors */ 077 descriptors */ 082 *kernel_core_base = SOS_PAGE_ALIGN_INF((sos_ 078 *kernel_core_base = SOS_PAGE_ALIGN_INF((sos_paddr_t)(& __b_kernel)); 083 *kernel_core_top 079 *kernel_core_top 084 = PAGE_DESCR_ARRAY_ADDR 080 = PAGE_DESCR_ARRAY_ADDR 085 + SOS_PAGE_ALIGN_SUP( (ram_size >> SOS_P 081 + SOS_PAGE_ALIGN_SUP( (ram_size >> SOS_PAGE_SHIFT) 086 * sizeof(struct ph 082 * sizeof(struct physical_page_descr)); 087 if (*kernel_core_top > ram_size) 083 if (*kernel_core_top > ram_size) 088 return -SOS_ENOMEM; 084 return -SOS_ENOMEM; 089 085 090 /* Page 0-4kB is not available in order to r 086 /* Page 0-4kB is not available in order to return address 0 as a 091 means to signal "no page available" */ 087 means to signal "no page available" */ 092 physmem_base = SOS_PAGE_SIZE; 088 physmem_base = SOS_PAGE_SIZE; 093 physmem_top = ram_size; 089 physmem_top = ram_size; 094 090 095 /* Setup the page descriptor arrray */ 091 /* Setup the page descriptor arrray */ 096 physical_page_descr_array 092 physical_page_descr_array 097 = (struct physical_page_descr*)PAGE_DESCR_ 093 = (struct physical_page_descr*)PAGE_DESCR_ARRAY_ADDR; 098 094 099 /* Scan the list of physical pages */ 095 /* Scan the list of physical pages */ 100 for (ppage_addr = 0, 096 for (ppage_addr = 0, 101 ppage_descr = physical_page_descr_arr 097 ppage_descr = physical_page_descr_array ; 102 ppage_addr < physmem_top ; 098 ppage_addr < physmem_top ; 103 ppage_addr += SOS_PAGE_SIZE, 099 ppage_addr += SOS_PAGE_SIZE, 104 ppage_descr ++) 100 ppage_descr ++) 105 { 101 { 106 enum { PPAGE_MARK_RESERVED, PPAGE_MARK_F 102 enum { PPAGE_MARK_RESERVED, PPAGE_MARK_FREE, 107 PPAGE_MARK_KERNEL, PPAGE_MARK_HWM 103 PPAGE_MARK_KERNEL, PPAGE_MARK_HWMAP } todo; 108 104 109 memset(ppage_descr, 0x0, sizeof(struct p 105 memset(ppage_descr, 0x0, sizeof(struct physical_page_descr)); 110 106 111 /* Init the page descriptor for this pag 107 /* Init the page descriptor for this page */ 112 ppage_descr->paddr = ppage_addr; 108 ppage_descr->paddr = ppage_addr; 113 109 114 /* Reserved : 0 ... base */ 110 /* Reserved : 0 ... base */ 115 if (ppage_addr < physmem_base) 111 if (ppage_addr < physmem_base) 116 todo = PPAGE_MARK_RESERVED; 112 todo = PPAGE_MARK_RESERVED; 117 113 118 /* Free : base ... BIOS */ 114 /* Free : base ... BIOS */ 119 else if ((ppage_addr >= physmem_base) 115 else if ((ppage_addr >= physmem_base) 120 && (ppage_addr < BIOS_N_VIDEO_S 116 && (ppage_addr < BIOS_N_VIDEO_START)) 121 todo = PPAGE_MARK_FREE; 117 todo = PPAGE_MARK_FREE; 122 118 123 /* Used : BIOS */ 119 /* Used : BIOS */ 124 else if ((ppage_addr >= BIOS_N_VIDEO_STA 120 else if ((ppage_addr >= BIOS_N_VIDEO_START) 125 && (ppage_addr < BIOS_N_VIDEO_E 121 && (ppage_addr < BIOS_N_VIDEO_END)) 126 todo = PPAGE_MARK_HWMAP; 122 todo = PPAGE_MARK_HWMAP; 127 123 128 /* Free : BIOS ... kernel */ 124 /* Free : BIOS ... kernel */ 129 else if ((ppage_addr >= BIOS_N_VIDEO_END 125 else if ((ppage_addr >= BIOS_N_VIDEO_END) 130 && (ppage_addr < (sos_paddr_t) 126 && (ppage_addr < (sos_paddr_t) (& __b_kernel))) 131 todo = PPAGE_MARK_FREE; 127 todo = PPAGE_MARK_FREE; 132 128 133 /* Used : Kernel code/data/bss + physcal 129 /* Used : Kernel code/data/bss + physcal page descr array */ 134 else if ((ppage_addr >= *kernel_core_bas 130 else if ((ppage_addr >= *kernel_core_base) 135 && (ppage_addr < *kernel_core_ 131 && (ppage_addr < *kernel_core_top)) 136 todo = PPAGE_MARK_KERNEL; 132 todo = PPAGE_MARK_KERNEL; 137 133 138 /* Free : first page of descr ... end of 134 /* Free : first page of descr ... end of RAM */ 139 else 135 else 140 todo = PPAGE_MARK_FREE; 136 todo = PPAGE_MARK_FREE; 141 137 142 /* Actually does the insertion in the us 138 /* Actually does the insertion in the used/free page lists */ 143 physmem_total_pages ++; 139 physmem_total_pages ++; 144 switch (todo) 140 switch (todo) 145 { 141 { 146 case PPAGE_MARK_FREE: 142 case PPAGE_MARK_FREE: 147 ppage_descr->ref_cnt = 0; 143 ppage_descr->ref_cnt = 0; 148 list_add_head(free_ppage, ppage_desc 144 list_add_head(free_ppage, ppage_descr); 149 break; 145 break; 150 146 151 case PPAGE_MARK_KERNEL: 147 case PPAGE_MARK_KERNEL: 152 case PPAGE_MARK_HWMAP: 148 case PPAGE_MARK_HWMAP: 153 ppage_descr->ref_cnt = 1; 149 ppage_descr->ref_cnt = 1; 154 list_add_head(used_ppage, ppage_desc 150 list_add_head(used_ppage, ppage_descr); 155 physmem_used_pages ++; 151 physmem_used_pages ++; 156 break; 152 break; 157 153 158 default: 154 default: 159 /* Reserved page: nop */ 155 /* Reserved page: nop */ 160 break; 156 break; 161 } 157 } 162 } 158 } 163 159 164 return SOS_OK; 160 return SOS_OK; 165 } 161 } 166 162 167 163 168 sos_paddr_t sos_physmem_ref_physpage_new(sos_b 164 sos_paddr_t sos_physmem_ref_physpage_new(sos_bool_t can_block) 169 { 165 { 170 struct physical_page_descr *ppage_descr; 166 struct physical_page_descr *ppage_descr; 171 167 172 if (! free_ppage) 168 if (! free_ppage) 173 return (sos_paddr_t)NULL; 169 return (sos_paddr_t)NULL; 174 170 175 /* Retrieve a page in the free list */ 171 /* Retrieve a page in the free list */ 176 ppage_descr = list_pop_head(free_ppage); 172 ppage_descr = list_pop_head(free_ppage); 177 173 178 /* The page is assumed not to be already use 174 /* The page is assumed not to be already used */ 179 SOS_ASSERT_FATAL(ppage_descr->ref_cnt == 0); 175 SOS_ASSERT_FATAL(ppage_descr->ref_cnt == 0); 180 176 181 /* Mark the page as used (this of course set 177 /* Mark the page as used (this of course sets the ref count to 1) */ 182 ppage_descr->ref_cnt ++; 178 ppage_descr->ref_cnt ++; 183 179 184 /* No associated kernel range by default */ << 185 ppage_descr->kernel_range = NULL; << 186 << 187 /* Put the page in the used list */ 180 /* Put the page in the used list */ 188 list_add_tail(used_ppage, ppage_descr); 181 list_add_tail(used_ppage, ppage_descr); 189 physmem_used_pages ++; 182 physmem_used_pages ++; 190 183 191 return ppage_descr->paddr; 184 return ppage_descr->paddr; 192 } 185 } 193 186 194 187 195 /** 188 /** 196 * Helper function to get the physical page de 189 * Helper function to get the physical page descriptor for the given 197 * physical page address. 190 * physical page address. 198 * 191 * 199 * @return NULL when out-of-bounds or non-page 192 * @return NULL when out-of-bounds or non-page-aligned 200 */ 193 */ 201 inline static struct physical_page_descr * 194 inline static struct physical_page_descr * 202 get_page_descr_at_paddr(sos_paddr_t ppage_padd 195 get_page_descr_at_paddr(sos_paddr_t ppage_paddr) 203 { 196 { 204 /* Don't handle non-page-aligned addresses * 197 /* Don't handle non-page-aligned addresses */ 205 if (ppage_paddr & SOS_PAGE_MASK) 198 if (ppage_paddr & SOS_PAGE_MASK) 206 return NULL; 199 return NULL; 207 200 208 /* Don't support out-of-bounds requests */ 201 /* Don't support out-of-bounds requests */ 209 if ((ppage_paddr < physmem_base) || (ppage_p 202 if ((ppage_paddr < physmem_base) || (ppage_paddr >= physmem_top)) 210 return NULL; 203 return NULL; 211 204 212 return physical_page_descr_array + (ppage_pa 205 return physical_page_descr_array + (ppage_paddr >> SOS_PAGE_SHIFT); 213 } 206 } 214 207 215 208 216 sos_ret_t sos_physmem_ref_physpage_at(sos_padd 209 sos_ret_t sos_physmem_ref_physpage_at(sos_paddr_t ppage_paddr) 217 { 210 { 218 struct physical_page_descr *ppage_descr 211 struct physical_page_descr *ppage_descr 219 = get_page_descr_at_paddr(ppage_paddr); 212 = get_page_descr_at_paddr(ppage_paddr); 220 213 221 if (! ppage_descr) 214 if (! ppage_descr) 222 return -SOS_EINVAL; 215 return -SOS_EINVAL; 223 216 224 /* Increment the reference count for the pag 217 /* Increment the reference count for the page */ 225 ppage_descr->ref_cnt ++; 218 ppage_descr->ref_cnt ++; 226 219 227 /* If the page is newly referenced (ie we ar 220 /* If the page is newly referenced (ie we are the only owners of the 228 page => ref cnt == 1), transfer it in the 221 page => ref cnt == 1), transfer it in the used pages list */ 229 if (ppage_descr->ref_cnt == 1) 222 if (ppage_descr->ref_cnt == 1) 230 { 223 { 231 list_delete(free_ppage, ppage_descr); 224 list_delete(free_ppage, ppage_descr); 232 << 233 /* No associated kernel range by default << 234 ppage_descr->kernel_range = NULL; << 235 << 236 list_add_tail(used_ppage, ppage_descr); 225 list_add_tail(used_ppage, ppage_descr); 237 physmem_used_pages ++; 226 physmem_used_pages ++; 238 227 239 /* The page is newly referenced */ 228 /* The page is newly referenced */ 240 return FALSE; 229 return FALSE; 241 } 230 } 242 231 243 /* The page was already referenced by someon 232 /* The page was already referenced by someone */ 244 return TRUE; 233 return TRUE; 245 } 234 } 246 235 247 236 248 sos_ret_t 237 sos_ret_t 249 sos_physmem_unref_physpage(sos_paddr_t ppage_p 238 sos_physmem_unref_physpage(sos_paddr_t ppage_paddr) 250 { 239 { 251 /* By default the return value indicates tha 240 /* By default the return value indicates that the page is still 252 used */ 241 used */ 253 sos_ret_t retval = FALSE; 242 sos_ret_t retval = FALSE; 254 243 255 struct physical_page_descr *ppage_descr 244 struct physical_page_descr *ppage_descr 256 = get_page_descr_at_paddr(ppage_paddr); 245 = get_page_descr_at_paddr(ppage_paddr); 257 246 258 if (! ppage_descr) 247 if (! ppage_descr) 259 return -SOS_EINVAL; 248 return -SOS_EINVAL; 260 249 261 /* Don't do anything if the page is not in t 250 /* Don't do anything if the page is not in the used list */ 262 if (ppage_descr->ref_cnt <= 0) 251 if (ppage_descr->ref_cnt <= 0) 263 return -SOS_EINVAL; 252 return -SOS_EINVAL; 264 253 265 /* Unreference the page, and, when no mappin 254 /* Unreference the page, and, when no mapping is active anymore, put 266 the page in the free list */ 255 the page in the free list */ 267 ppage_descr->ref_cnt--; 256 ppage_descr->ref_cnt--; 268 if (ppage_descr->ref_cnt <= 0) 257 if (ppage_descr->ref_cnt <= 0) 269 { 258 { 270 /* Reset associated kernel range */ << 271 ppage_descr->kernel_range = NULL; << 272 << 273 /* Transfer the page, considered USED, t 259 /* Transfer the page, considered USED, to the free list */ 274 list_delete(used_ppage, ppage_descr); 260 list_delete(used_ppage, ppage_descr); 275 physmem_used_pages --; 261 physmem_used_pages --; 276 list_add_head(free_ppage, ppage_descr); 262 list_add_head(free_ppage, ppage_descr); 277 263 278 /* Indicate that the page is now unrefer 264 /* Indicate that the page is now unreferenced */ 279 retval = TRUE; 265 retval = TRUE; 280 } 266 } 281 267 282 return retval; 268 return retval; 283 } << 284 << 285 << 286 struct sos_kmem_range* sos_physmem_get_kmem_ra << 287 { << 288 struct physical_page_descr *ppage_descr << 289 = get_page_descr_at_paddr(ppage_paddr); << 290 << 291 if (! ppage_descr) << 292 return NULL; << 293 << 294 return ppage_descr->kernel_range; << 295 } << 296 << 297 << 298 sos_ret_t sos_physmem_set_kmem_range(sos_paddr << 299 struct so << 300 { << 301 struct physical_page_descr *ppage_descr << 302 = get_page_descr_at_paddr(ppage_paddr); << 303 << 304 if (! ppage_descr) << 305 return -SOS_EINVAL; << 306 << 307 ppage_descr->kernel_range = range; << 308 return SOS_OK; << 309 } << 310 << 311 sos_ret_t sos_physmem_get_state(/* out */sos_c << 312 /* out */sos_c << 313 { << 314 if (total_ppages) << 315 *total_ppages = physmem_total_pages; << 316 if (used_ppages) << 317 *used_ppages = physmem_used_pages; << 318 return SOS_OK; << 319 } 269 }
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