1 // Post memory manager (PMM) calls
3 // Copyright (C) 2009 Kevin O'Connor <kevin@koconnor.net>
5 // This file may be distributed under the terms of the GNU LGPLv3 license.
7 #include "util.h" // checksum
8 #include "config.h" // BUILD_BIOS_ADDR
9 #include "memmap.h" // find_high_area
10 #include "farptr.h" // GET_FARVAR
11 #include "biosvar.h" // GET_BDA
15 // The 16bit pmm entry points runs in "big real" mode, and can
16 // therefore read/write to the 32bit malloc variables.
17 #define GET_PMMVAR(var) ({ \
19 __GET_VAR("addr32 ", ES, (var)); })
20 #define SET_PMMVAR(var, val) do { \
22 __SET_VAR("addr32 ", ES, (var), (val)); \
25 #define GET_PMMVAR(var) (var)
26 #define SET_PMMVAR(var, val) do { (var) = (val); } while (0)
34 struct zone_s ZoneLow VAR32FLATVISIBLE, ZoneHigh VAR32FLATVISIBLE;
35 struct zone_s ZoneFSeg VAR32FLATVISIBLE;
36 struct zone_s ZoneTmpLow VAR32FLATVISIBLE, ZoneTmpHigh VAR32FLATVISIBLE;
38 struct zone_s *Zones[] VAR32FLATVISIBLE = {
39 &ZoneTmpLow, &ZoneLow, &ZoneFSeg, &ZoneTmpHigh, &ZoneHigh
43 /****************************************************************
45 ****************************************************************/
49 relocate_ebda(u32 newebda, u32 oldebda, u8 ebda_size)
51 u32 lowram = GET_BDA(mem_size_kb) * 1024;
52 if (oldebda != lowram)
53 // EBDA isn't at end of ram - give up.
58 memcpy_far(FLATPTR_TO_SEG(newebda)
59 , (void*)FLATPTR_TO_OFFSET(newebda)
60 , FLATPTR_TO_SEG(oldebda)
61 , (void*)FLATPTR_TO_OFFSET(oldebda)
64 memmove((void*)newebda, (void*)oldebda, ebda_size * 1024);
67 dprintf(1, "ebda moved from %x to %x\n", oldebda, newebda);
68 SET_BDA(mem_size_kb, newebda / 1024);
69 SET_BDA(ebda_seg, FLATPTR_TO_SEG(newebda));
73 // Support expanding the ZoneLow dynamically.
75 zonelow_expand(u32 size, u32 align)
77 u32 oldpos = GET_PMMVAR(ZoneLow.cur);
78 u32 newpos = ALIGN_DOWN(oldpos - size, align);
79 u32 bottom = GET_PMMVAR(ZoneLow.bottom);
80 if (newpos >= bottom && newpos <= oldpos)
81 // Space already present.
83 u16 ebda_seg = get_ebda_seg();
84 u32 ebda_pos = (u32)MAKE_FLATPTR(ebda_seg, 0);
85 u8 ebda_size = GET_EBDA2(ebda_seg, size);
86 u32 ebda_end = ebda_pos + ebda_size * 1024;
87 if (ebda_end != bottom) {
88 // Something else is after ebda - can't use any existing space.
90 newpos = ALIGN_DOWN(oldpos - size, align);
92 u32 newbottom = ALIGN_DOWN(newpos, 1024);
93 u32 newebda = ALIGN_DOWN(newbottom - ebda_size * 1024, 1024);
94 if (newebda < BUILD_EBDA_MINIMUM)
99 int ret = relocate_ebda(newebda, ebda_pos, ebda_size);
104 SET_PMMVAR(ZoneLow.cur, oldpos);
105 SET_PMMVAR(ZoneLow.bottom, newbottom);
109 /****************************************************************
111 ****************************************************************/
113 // Obtain memory from a given zone.
115 zone_malloc(struct zone_s *zone, u32 size, u32 align)
117 u32 oldpos = GET_PMMVAR(zone->cur);
118 u32 newpos = ALIGN_DOWN(oldpos - size, align);
119 if (newpos < GET_PMMVAR(zone->bottom) || newpos > oldpos)
122 SET_PMMVAR(zone->cur, newpos);
123 return (void*)newpos;
126 // Find the zone that contains the given data block.
127 static struct zone_s *
128 zone_find(void *data)
131 for (i=0; i<ARRAY_SIZE(Zones); i++) {
132 struct zone_s *zone = GET_PMMVAR(Zones[i]);
133 if ((u32)data >= GET_PMMVAR(zone->cur)
134 && (u32)data < GET_PMMVAR(zone->top))
140 // Return memory to a zone (if it was the last to be allocated).
142 zone_free(void *data, u32 olddata)
144 struct zone_s *zone = zone_find(data);
145 if (!zone || !data || GET_PMMVAR(zone->cur) != (u32)data)
147 SET_PMMVAR(zone->cur, olddata);
151 // Report the status of all the zones.
156 for (i=0; i<ARRAY_SIZE(Zones); i++) {
157 struct zone_s *zone = Zones[i];
158 u32 used = zone->top - zone->cur;
159 u32 avail = zone->top - zone->bottom;
160 u32 pct = avail ? ((100 * used) / avail) : 0;
161 dprintf(2, "zone %d: %08x-%08x used=%d (%d%%)\n"
162 , i, zone->bottom, zone->top, used, pct);
167 /****************************************************************
168 * tracked memory allocations
169 ****************************************************************/
171 // Information on PMM tracked allocations
177 struct pmmalloc_s *next;
180 struct pmmalloc_s *PMMAllocs VAR32FLATVISIBLE;
182 // Allocate memory from the given zone and track it as a PMM allocation
184 pmm_malloc(struct zone_s *zone, u32 handle, u32 size, u32 align)
186 u32 oldallocdata = GET_PMMVAR(ZoneTmpHigh.cur);
187 struct pmmalloc_s *info = zone_malloc(&ZoneTmpHigh, sizeof(*info)
190 oldallocdata = GET_PMMVAR(ZoneTmpLow.cur);
191 info = zone_malloc(&ZoneTmpLow, sizeof(*info), MALLOC_MIN_ALIGN);
195 if (zone == &ZoneLow)
196 zonelow_expand(size, align);
197 u32 olddata = GET_PMMVAR(zone->cur);
198 void *data = zone_malloc(zone, size, align);
200 zone_free(info, oldallocdata);
203 dprintf(8, "pmm_malloc zone=%p handle=%x size=%d align=%x"
204 " ret=%p (info=%p)\n"
205 , zone, handle, size, align
207 SET_PMMVAR(info->data, data);
208 SET_PMMVAR(info->olddata, olddata);
209 SET_PMMVAR(info->handle, handle);
210 SET_PMMVAR(info->oldallocdata, oldallocdata);
211 SET_PMMVAR(info->next, GET_PMMVAR(PMMAllocs));
212 SET_PMMVAR(PMMAllocs, info);
216 // Free a raw data block (either from a zone or from pmm alloc list).
218 pmm_free_data(void *data, u32 olddata)
220 int ret = zone_free(data, olddata);
224 struct pmmalloc_s *info;
225 for (info=GET_PMMVAR(PMMAllocs); info; info = GET_PMMVAR(info->next))
226 if (GET_PMMVAR(info->olddata) == (u32)data) {
227 SET_PMMVAR(info->olddata, olddata);
229 } else if (GET_PMMVAR(info->oldallocdata) == (u32)data) {
230 SET_PMMVAR(info->oldallocdata, olddata);
235 // Free a data block allocated with pmm_malloc
239 struct pmmalloc_s **pinfo = &PMMAllocs;
241 struct pmmalloc_s *info = GET_PMMVAR(*pinfo);
244 if (GET_PMMVAR(info->data) == data) {
245 SET_PMMVAR(*pinfo, GET_PMMVAR(info->next));
246 u32 oldallocdata = GET_PMMVAR(info->oldallocdata);
247 u32 olddata = GET_PMMVAR(info->olddata);
248 pmm_free_data(data, olddata);
249 pmm_free_data(info, oldallocdata);
250 dprintf(8, "pmm_free data=%p olddata=%p oldallocdata=%p info=%p\n"
251 , data, (void*)olddata, (void*)oldallocdata, info);
258 // Find the amount of free space in a given zone.
260 pmm_getspace(struct zone_s *zone)
262 // XXX - doesn't account for ZoneLow being able to grow.
263 u32 space = GET_PMMVAR(zone->cur) - GET_PMMVAR(zone->bottom);
264 if (zone != &ZoneTmpHigh && zone != &ZoneTmpLow)
266 // Account for space needed for PMM tracking.
267 u32 reserve = ALIGN(sizeof(struct pmmalloc_s), MALLOC_MIN_ALIGN);
268 if (space <= reserve)
270 return space - reserve;
273 // Find the data block allocated with pmm_malloc with a given handle.
277 struct pmmalloc_s *info;
278 for (info=GET_PMMVAR(PMMAllocs); info; info = GET_PMMVAR(info->next))
279 if (GET_PMMVAR(info->handle) == handle)
280 return GET_PMMVAR(info->data);
288 dprintf(3, "malloc setup\n");
292 // Memory in 0xf0000 area.
293 extern u8 code32_start[];
294 if ((u32)code32_start > BUILD_BIOS_ADDR)
295 // Clear unused parts of f-segment
296 memset((void*)BUILD_BIOS_ADDR, 0, (u32)code32_start - BUILD_BIOS_ADDR);
297 memset(BiosTableSpace, 0, CONFIG_MAX_BIOSTABLE);
298 ZoneFSeg.bottom = (u32)BiosTableSpace;
299 ZoneFSeg.top = ZoneFSeg.cur = ZoneFSeg.bottom + CONFIG_MAX_BIOSTABLE;
301 // Memory under 1Meg.
302 ZoneTmpLow.bottom = BUILD_STACK_ADDR;
303 ZoneTmpLow.top = ZoneTmpLow.cur = BUILD_EBDA_MINIMUM;
305 // Permanent memory under 1Meg.
306 ZoneLow.bottom = ZoneLow.top = ZoneLow.cur = BUILD_LOWRAM_END;
308 // Find memory at the top of ram.
309 struct e820entry *e = find_high_area(CONFIG_MAX_HIGHTABLE+MALLOC_MIN_ALIGN);
311 // No memory above 1Meg
312 memset(&ZoneHigh, 0, sizeof(ZoneHigh));
313 memset(&ZoneTmpHigh, 0, sizeof(ZoneTmpHigh));
316 u32 top = e->start + e->size, bottom = e->start;
318 // Memory at top of ram.
319 ZoneHigh.bottom = ALIGN(top - CONFIG_MAX_HIGHTABLE, MALLOC_MIN_ALIGN);
320 ZoneHigh.top = ZoneHigh.cur = ZoneHigh.bottom + CONFIG_MAX_HIGHTABLE;
321 add_e820(ZoneHigh.bottom, CONFIG_MAX_HIGHTABLE, E820_RESERVED);
324 ZoneTmpHigh.bottom = ALIGN(bottom, MALLOC_MIN_ALIGN);
325 ZoneTmpHigh.top = ZoneTmpHigh.cur = ZoneHigh.bottom;
331 dprintf(3, "malloc finalize\n");
335 // Reserve more low-mem if needed.
336 u32 endlow = GET_BDA(mem_size_kb)*1024;
337 add_e820(endlow, BUILD_LOWRAM_END-endlow, E820_RESERVED);
339 // Give back unused high ram.
340 u32 giveback = ALIGN_DOWN(ZoneHigh.cur - ZoneHigh.bottom, PAGE_SIZE);
341 add_e820(ZoneHigh.bottom, giveback, E820_RAM);
342 dprintf(1, "Returned %d bytes of ZoneHigh\n", giveback);
344 // Clear low-memory allocations.
345 memset((void*)ZoneTmpLow.bottom, 0, ZoneTmpLow.top - ZoneTmpLow.bottom);
349 /****************************************************************
351 ****************************************************************/
363 extern struct pmmheader PMMHEADER;
365 #define PMM_SIGNATURE 0x4d4d5024 // $PMM
368 struct pmmheader PMMHEADER __aligned(16) VAR16EXPORT = {
370 .length = sizeof(PMMHEADER),
371 .entry_seg = SEG_BIOS,
375 #define PMM_FUNCTION_NOT_SUPPORTED 0xffffffff
379 handle_pmm00(u16 *args)
381 u32 length = *(u32*)&args[1], handle = *(u32*)&args[3];
383 dprintf(3, "pmm00: length=%x handle=%x flags=%x\n"
384 , length, handle, flags);
385 struct zone_s *lowzone = &ZoneTmpLow, *highzone = &ZoneTmpHigh;
387 // Permanent memory request.
389 highzone = &ZoneHigh;
392 // Memory size request
398 return pmm_getspace(lowzone);
400 return pmm_getspace(highzone);
402 u32 spacelow = pmm_getspace(lowzone);
403 u32 spacehigh = pmm_getspace(highzone);
404 if (spacelow > spacehigh)
410 u32 size = length * 16;
413 u32 align = MALLOC_MIN_ALIGN;
415 align = 1<<__ffs(size);
416 if (align < MALLOC_MIN_ALIGN)
417 align = MALLOC_MIN_ALIGN;
424 return (u32)pmm_malloc(lowzone, handle, size, align);
426 return (u32)pmm_malloc(highzone, handle, size, align);
428 void *data = pmm_malloc(lowzone, handle, size, align);
431 return (u32)pmm_malloc(highzone, handle, size, align);
438 handle_pmm01(u16 *args)
440 u32 handle = *(u32*)&args[1];
441 dprintf(3, "pmm01: handle=%x\n", handle);
442 if (handle == PMM_DEFAULT_HANDLE)
444 return (u32)pmm_find(handle);
449 handle_pmm02(u16 *args)
451 u32 buffer = *(u32*)&args[1];
452 dprintf(3, "pmm02: buffer=%x\n", buffer);
453 int ret = pmm_free((void*)buffer);
461 handle_pmmXX(u16 *args)
463 return PMM_FUNCTION_NOT_SUPPORTED;
467 handle_pmm(u16 *args)
470 return PMM_FUNCTION_NOT_SUPPORTED;
473 dprintf(DEBUG_HDL_pmm, "pmm call arg1=%x\n", arg1);
476 case 0x00: return handle_pmm00(args);
477 case 0x01: return handle_pmm01(args);
478 case 0x02: return handle_pmm02(args);
479 default: return handle_pmmXX(args);
484 extern void entry_pmm();
492 dprintf(3, "init PMM\n");
494 PMMHEADER.signature = PMM_SIGNATURE;
495 PMMHEADER.entry_offset = (u32)entry_pmm - BUILD_BIOS_ADDR;
496 PMMHEADER.checksum -= checksum(&PMMHEADER, sizeof(PMMHEADER));
505 dprintf(3, "finalize PMM\n");
507 PMMHEADER.signature = 0;
508 PMMHEADER.entry_offset = 0;