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