xref: /reactos/subsystems/mvdm/ntvdm/bios/umamgr.c (revision c2c66aff)
1 /*
2  * COPYRIGHT:       GPLv2+ - See COPYING in the top level directory
3  * PROJECT:         ReactOS Virtual DOS Machine
4  * FILE:            subsystems/mvdm/ntvdm/bios/umamgr.c
5  * PURPOSE:         Upper Memory Area Manager
6  * PROGRAMMERS:     Hermes Belusca-Maito (hermes.belusca@sfr.fr)
7  *
8  * NOTE: The UMA Manager is used by the DOS XMS Driver (UMB Provider part),
9  *       indirectly by the DOS EMS Driver, and by VDD memory management functions.
10  */
11 
12 /* INCLUDES *******************************************************************/
13 
14 #include "ntvdm.h"
15 
16 #define NDEBUG
17 #include <debug.h>
18 
19 #include "emulator.h"
20 #include "memory.h"
21 
22 #include "umamgr.h"
23 
24 /* PRIVATE VARIABLES **********************************************************/
25 
26 typedef struct _UMA_DESCRIPTOR
27 {
28     LIST_ENTRY Entry;
29     ULONG Start;
30     ULONG Size;
31     UMA_DESC_TYPE Type;
32 } UMA_DESCRIPTOR, *PUMA_DESCRIPTOR;
33 
34 /*
35  * Sorted list of UMA descriptors.
36  *
37  * The descriptor list is (and must always be) sorted by memory addresses,
38  * and all consecutive free descriptors are always merged together, so that
39  * free ones are always separated from each other by descriptors of other types.
40  *
41  * TODO: Add the fact that no blocks of size == 0 are allowed.
42  */
43 static LIST_ENTRY UmaDescriptorList = { &UmaDescriptorList, &UmaDescriptorList };
44 
45 /* PRIVATE FUNCTIONS **********************************************************/
46 
47 static PUMA_DESCRIPTOR
CreateUmaDescriptor(IN OUT PLIST_ENTRY ListHead,IN ULONG Address,IN ULONG Size,IN UMA_DESC_TYPE Type)48 CreateUmaDescriptor(IN OUT PLIST_ENTRY ListHead,
49                     IN ULONG Address,
50                     IN ULONG Size,
51                     IN UMA_DESC_TYPE Type)
52 {
53     PUMA_DESCRIPTOR UmaDesc;
54 
55     ASSERT(Size > 0);
56 
57     UmaDesc = RtlAllocateHeap(RtlGetProcessHeap(), HEAP_ZERO_MEMORY, sizeof(*UmaDesc));
58     if (!UmaDesc) return NULL;
59 
60     UmaDesc->Start = Address;
61     UmaDesc->Size  = Size;
62     UmaDesc->Type  = Type;
63 
64     /*
65      * We use the trick of http://www.osronline.com/article.cfm?article=499 to insert
66      * the new descriptor just after the current entry that we specify via 'ListHead'.
67      * If 'ListHead' is NULL then we insert the descriptor at the tail of 'UmaDescriptorList'
68      * (which is equivalent to inserting it at the head of 'UmaDescriptorList.Blink').
69      */
70     if (ListHead == NULL) ListHead = UmaDescriptorList.Blink;
71     InsertHeadList(ListHead, &UmaDesc->Entry);
72 
73     return UmaDesc;
74 }
75 
FreeUmaDescriptor(PUMA_DESCRIPTOR UmaDesc)76 static VOID FreeUmaDescriptor(PUMA_DESCRIPTOR UmaDesc)
77 {
78     RemoveEntryList(&UmaDesc->Entry);
79     RtlFreeHeap(RtlGetProcessHeap(), 0, UmaDesc);
80 }
81 
82 /* PUBLIC FUNCTIONS ***********************************************************/
83 
UmaDescReserve(IN OUT PUSHORT Segment,IN OUT PUSHORT Size)84 BOOLEAN UmaDescReserve(IN OUT PUSHORT Segment, IN OUT PUSHORT Size)
85 {
86     ULONG Address =  (*Segment << 4); // Convert segment number into address.
87     ULONG RequestSize = (*Size << 4); // Convert size in paragraphs into size in bytes.
88     ULONG MaxSize = 0;
89     PLIST_ENTRY Entry;
90     PUMA_DESCRIPTOR UmaDesc, NewUmaDesc;
91     PUMA_DESCRIPTOR FoundUmaDesc = NULL;
92 
93     // FIXME: Check! What to do?
94     if (RequestSize == 0) DPRINT1("Requesting UMA descriptor with null size?!\n");
95 
96     Entry = UmaDescriptorList.Flink;
97     while (Entry != &UmaDescriptorList)
98     {
99         UmaDesc = (PUMA_DESCRIPTOR)CONTAINING_RECORD(Entry, UMA_DESCRIPTOR, Entry);
100         Entry = Entry->Flink;
101 
102         /* Only check free descriptors */
103         if (UmaDesc->Type != UMA_FREE) continue;
104 
105         /* Update the maximum descriptor size */
106         if (UmaDesc->Size > MaxSize) MaxSize = UmaDesc->Size;
107 
108         /* Descriptor too small, continue... */
109         if (UmaDesc->Size < RequestSize) continue;
110 
111         /* Do we want to reserve the descriptor at a precise address? */
112         if (Address)
113         {
114             /* If the descriptor ends before the desired region, try again */
115             if (UmaDesc->Start + UmaDesc->Size <= Address) continue;
116 
117             /*
118              * If we have a descriptor, but one of its boundaries crosses the
119              * desired region (it starts after the desired region, or ends
120              * before the end of the desired region), this means that there
121              * is already something inside the region, so that we cannot
122              * allocate the region here. Bail out.
123              */
124             if (UmaDesc->Start > Address ||
125                 UmaDesc->Start + UmaDesc->Size < Address + RequestSize)
126             {
127                 goto Fail;
128             }
129 
130             /* We now have a free descriptor that overlaps our desired region: split it */
131 
132             /*
133              * Here, UmaDesc->Start == Address or UmaDesc->Start < Address,
134              * in which case we need to split the descriptor to the left.
135              */
136             if (UmaDesc->Start < Address)
137             {
138                 /* Create a new free descriptor and insert it after the current one */
139                 NewUmaDesc = CreateUmaDescriptor(&UmaDesc->Entry,
140                                                  Address,
141                                                  UmaDesc->Size - (Address - UmaDesc->Start),
142                                                  UmaDesc->Type); // UMA_FREE
143                 if (!NewUmaDesc)
144                 {
145                     DPRINT1("CreateUmaDescriptor failed, UMA descriptor list possibly corrupted!\n");
146                     goto Fail;
147                 }
148 
149                 /* Reduce the size of the splitted left descriptor */
150                 UmaDesc->Size = (Address - UmaDesc->Start);
151 
152                 /* Current descriptor is now the new created one */
153                 UmaDesc = NewUmaDesc;
154             }
155 
156             /* Here, UmaDesc->Start == Address */
157         }
158 
159         /* Descriptor of large enough size: split it to the right if needed */
160         // FIXME: It might be needed to consider a minimum size starting which we need to split.
161         // if (UmaDesc->Size - RequestSize > (3 << 4))
162         if (UmaDesc->Size > RequestSize)
163         {
164             /*
165              * Create a new free descriptor and insert it after the current one.
166              * Because consecutive free descriptors are always merged together,
167              * the descriptor following 'UmaDesc' cannot be free, so that this
168              * new free descriptor does not need to be merged with some others.
169              */
170             NewUmaDesc = CreateUmaDescriptor(&UmaDesc->Entry,
171                                              UmaDesc->Start + RequestSize,
172                                              UmaDesc->Size - RequestSize,
173                                              UmaDesc->Type); // UMA_FREE
174             if (!NewUmaDesc)
175             {
176                 DPRINT1("CreateUmaDescriptor failed, UMA descriptor list possibly corrupted!\n");
177                 goto Fail;
178             }
179 
180             /* Reduce the size of the splitted left descriptor */
181             UmaDesc->Size = RequestSize;
182         }
183 
184         /* We have a descriptor of correct size, initialize it */
185         UmaDesc->Type = UMA_UMB;
186         FoundUmaDesc = UmaDesc;
187         break;
188     }
189 
190     if (FoundUmaDesc)
191     {
192         /* Returned address is a segment and size is in paragraphs */
193         *Segment = (FoundUmaDesc->Start >> 4);
194         *Size    = (FoundUmaDesc->Size  >> 4);
195         return TRUE;
196     }
197     else
198     {
199 Fail:
200         /* Returned address is a segment and size is in paragraphs */
201         *Segment = 0x0000;
202         *Size    = (MaxSize >> 4);
203         return FALSE;
204     }
205 }
206 
UmaDescRelease(IN USHORT Segment)207 BOOLEAN UmaDescRelease(IN USHORT Segment)
208 {
209     ULONG Address = (Segment << 4); // Convert segment number into address.
210     PLIST_ENTRY Entry, PrevEntry, NextEntry;
211     PUMA_DESCRIPTOR UmaDesc, PrevDesc = NULL, NextDesc = NULL;
212     PUMA_DESCRIPTOR FoundUmaDesc = NULL;
213 
214     Entry = UmaDescriptorList.Flink;
215     while (Entry != &UmaDescriptorList)
216     {
217         UmaDesc = (PUMA_DESCRIPTOR)CONTAINING_RECORD(Entry, UMA_DESCRIPTOR, Entry);
218         Entry = Entry->Flink;
219 
220         /* Search for the descriptor in the list */
221         if (UmaDesc->Start == Address && UmaDesc->Type == UMA_UMB)
222         {
223             /* We found it */
224             FoundUmaDesc = UmaDesc;
225             break;
226         }
227     }
228 
229     if (FoundUmaDesc)
230     {
231         FoundUmaDesc->Type = UMA_FREE;
232 
233         /* Combine free descriptors adjacent to this one */
234         PrevEntry = FoundUmaDesc->Entry.Blink;
235         NextEntry = FoundUmaDesc->Entry.Flink;
236 
237         if (PrevEntry != &UmaDescriptorList)
238             PrevDesc = (PUMA_DESCRIPTOR)CONTAINING_RECORD(PrevEntry, UMA_DESCRIPTOR, Entry);
239         if (NextEntry != &UmaDescriptorList)
240             NextDesc = (PUMA_DESCRIPTOR)CONTAINING_RECORD(NextEntry, UMA_DESCRIPTOR, Entry);
241 
242         if (NextDesc && NextDesc->Type == FoundUmaDesc->Type) // UMA_FREE
243         {
244             FoundUmaDesc->Size += NextDesc->Size;
245             FreeUmaDescriptor(NextDesc);
246         }
247 
248         if (PrevDesc && PrevDesc->Type == FoundUmaDesc->Type) // UMA_FREE
249         {
250             PrevDesc->Size += FoundUmaDesc->Size;
251             FreeUmaDescriptor(FoundUmaDesc);
252         }
253 
254         return TRUE;
255     }
256 
257     return FALSE;
258 }
259 
UmaDescReallocate(IN USHORT Segment,IN OUT PUSHORT Size)260 BOOLEAN UmaDescReallocate(IN USHORT Segment, IN OUT PUSHORT Size)
261 {
262     ULONG Address =   (Segment << 4); // Convert segment number into address.
263     ULONG RequestSize = (*Size << 4); // Convert size in paragraphs into size in bytes.
264     ULONG MaxSize = 0;
265     PLIST_ENTRY Entry, NextEntry;
266     PUMA_DESCRIPTOR UmaDesc, NextDesc = NULL, NewUmaDesc;
267     PUMA_DESCRIPTOR FoundUmaDesc = NULL;
268 
269     // FIXME: Check! What to do?
270     if (RequestSize == 0) DPRINT1("Resizing UMA descriptor %04X to null size?!\n", Segment);
271 
272     Entry = UmaDescriptorList.Flink;
273     while (Entry != &UmaDescriptorList)
274     {
275         UmaDesc = (PUMA_DESCRIPTOR)CONTAINING_RECORD(Entry, UMA_DESCRIPTOR, Entry);
276         Entry = Entry->Flink;
277 
278         /* Only get the maximum size of free descriptors */
279         if (UmaDesc->Type == UMA_FREE)
280         {
281             /* Update the maximum descriptor size */
282             if (UmaDesc->Size > MaxSize) MaxSize = UmaDesc->Size;
283         }
284 
285         /* Search for the descriptor in the list */
286         if (UmaDesc->Start == Address && UmaDesc->Type == UMA_UMB)
287         {
288             /* We found it */
289             FoundUmaDesc = UmaDesc;
290             break;
291         }
292     }
293 
294     if (FoundUmaDesc)
295     {
296         /* If we do not resize anything, just quit with success */
297         if (FoundUmaDesc->Size == RequestSize) goto Success;
298 
299         NextEntry = FoundUmaDesc->Entry.Flink;
300 
301         if (NextEntry != &UmaDescriptorList)
302             NextDesc = (PUMA_DESCRIPTOR)CONTAINING_RECORD(NextEntry, UMA_DESCRIPTOR, Entry);
303 
304         /* Check for reduction or enlargement */
305         if (FoundUmaDesc->Size > RequestSize)
306         {
307             /* Reduction */
308 
309             /*
310              * Check if the next descriptor is free, in which case we
311              * extend it, otherwise we create a new free descriptor.
312              */
313             if (NextDesc && NextDesc->Type == UMA_FREE)
314             {
315                 /* Yes it is, expand its size and move it down */
316                 NextDesc->Size  += (FoundUmaDesc->Size - RequestSize);
317                 NextDesc->Start -= (FoundUmaDesc->Size - RequestSize);
318             }
319             else
320             {
321                 // FIXME: It might be needed to consider a minimum size starting which we need to split.
322                 // if (FoundUmaDesc->Size - RequestSize > (3 << 4))
323 
324                 /* Create a new free descriptor and insert it after the current one */
325                 NewUmaDesc = CreateUmaDescriptor(&FoundUmaDesc->Entry,
326                                                  FoundUmaDesc->Start + RequestSize,
327                                                  FoundUmaDesc->Size - RequestSize,
328                                                  FoundUmaDesc->Type);
329                 if (!NewUmaDesc)
330                 {
331                     DPRINT1("CreateUmaDescriptor failed, UMA descriptor list possibly corrupted!\n");
332                     MaxSize = 0;
333                     goto Fail;
334                 }
335             }
336         }
337         else // if (FoundUmaDesc->Size <= RequestSize)
338         {
339             /* Enlargement */
340 
341             /* Check whether the next descriptor is free and large enough for merging */
342             if (NextDesc && NextDesc->Type == UMA_FREE &&
343                 FoundUmaDesc->Size + NextDesc->Size >= RequestSize)
344             {
345                 /* Yes it is, reduce its size and move it up, and enlarge the reallocated descriptor */
346                 NextDesc->Size  -= (RequestSize - FoundUmaDesc->Size);
347                 NextDesc->Start += (RequestSize - FoundUmaDesc->Size);
348 
349                 if (NextDesc->Size == 0) FreeUmaDescriptor(NextDesc);
350             }
351             else
352             {
353                 MaxSize = 0;
354                 goto Fail;
355             }
356         }
357 
358         /* Finally, resize the descriptor */
359         FoundUmaDesc->Size = RequestSize;
360 
361 Success:
362         /* Returned size is in paragraphs */
363         *Size = (FoundUmaDesc->Size >> 4);
364         return TRUE;
365     }
366     else
367     {
368 Fail:
369         /* Returned size is in paragraphs */
370         *Size = (MaxSize >> 4);
371         return FALSE;
372     }
373 }
374 
UmaMgrInitialize(VOID)375 BOOLEAN UmaMgrInitialize(VOID)
376 {
377 // See bios/rom.h
378 #define ROM_AREA_START  0xE0000
379 #define ROM_AREA_END    0xFFFFF
380 
381 #define OPTION_ROM_SIGNATURE    0xAA55
382 
383     PUMA_DESCRIPTOR UmaDesc = NULL;
384     ULONG StartAddress = 0;
385     ULONG Size = 0;
386     UMA_DESC_TYPE Type = UMA_FREE;
387 
388     UINT i;
389 
390     ULONG Start, End;
391     ULONG Increment;
392 
393     ULONG Address;
394 
395     // ULONG RomStart[]   = {};
396     // ULONG RomEnd[]   = {};
397     ULONG RomBoundaries[] = {0xA0000, 0xC0000, /*0xC8000, 0xE0000,*/ 0xF0000, 0x100000};
398     ULONG SizeIncrement[] = {0x20000, 0x00800, /*0x00800, 0x10000,*/ 0x10000, 0x0000  };
399 
400     // InitializeListHead(&UmaDescriptorList);
401 
402     /* NOTE: There must be always one UMA descriptor at least */
403     // FIXME: Maybe it should be a static object?
404 
405     for (i = 0; i < ARRAYSIZE(RomBoundaries) - 1; i++)
406     {
407         Start = RomBoundaries[i];   // RomStart[i]
408         End   = RomBoundaries[i+1]; // RomEnd[i]
409         Increment = SizeIncrement[i];
410 
411         for (Address = Start; Address < End; Address += Increment)
412         {
413             if (StartAddress == 0)
414             {
415                 /* Initialize data for a new descriptor */
416                 StartAddress = Address;
417                 Size = 0;
418                 Type = UMA_FREE;
419             }
420 
421             /* Is it a normal system zone/user-excluded zone? */
422             if (Address >= 0xA0000 && Address < 0xC0000)
423             {
424                 // StartAddress = Address;
425                 Size = Increment;
426                 Type = UMA_SYSTEM;
427 
428                 /* Create descriptor */
429                 UmaDesc = CreateUmaDescriptor(NULL, StartAddress, Size, Type);
430                 if (!UmaDesc) return FALSE;
431 
432                 StartAddress = 0;
433                 continue;
434             }
435             /* Is it the PC ROM BIOS? */
436             else if (Address >= 0xF0000)
437             {
438                 // StartAddress = Address;
439                 Size = 0x10000; // Increment;
440                 Type = UMA_ROM;
441 
442                 /* Create descriptor */
443                 UmaDesc = CreateUmaDescriptor(NULL, StartAddress, Size, Type);
444                 if (!UmaDesc) return FALSE;
445 
446                 StartAddress = 0;
447                 continue;
448             }
449             /* Is it an option ROM? */
450             else if (Address >= 0xC0000 && Address < 0xF0000)
451             {
452                 ULONG RomSize;
453                 ULONG PrevRomAddress = 0;
454                 ULONG PrevRomSize = 0;
455 
456                 // while (Address < 0xF0000)
457                 for (; Address < 0xF0000; Address += Increment)
458                 {
459 
460 #if 0 // FIXME: Is this block, better here...
461                     {
462                         // We may be looping inside a ROM block, if: Type == 2 and:
463                         // (StartAddress <= Address &&) StartAddress + Size > Address.
464                         // In this case, do nothing (do not increase size either)
465                         // But if we are now outside of a ROM block, then we need
466                         // to create the previous block, and initialize a new empty one!
467                         // (and following the next passages, increase its size).
468 
469                         // if (StartAddress < Address && Type != 2)
470                         if (Type == UMA_ROM && StartAddress + Size > Address)
471                         {
472                             /* We are inside ROM, do nothing */
473                         }
474                         else if (Type == UMA_ROM && StartAddress + Size <= Address)
475                         {
476                             /* We finished a ROM descriptor */
477 
478                             /* Create descriptor */
479                             UmaDesc = CreateUmaDescriptor(NULL, StartAddress, Size, Type);
480                             if (!UmaDesc) return FALSE;
481 
482                             StartAddress = 0;
483                             // goto Restart;
484                         }
485                         else if (Type != UMA_ROM)
486                         {
487                             Size += Increment;
488                         }
489                     }
490 #endif
491 
492 Restart:
493                     /// if (Address >= 0xE0000) { Increment = 0x10000; }
494 
495                     if (StartAddress == 0)
496                     {
497                         /* Initialize data for a new descriptor */
498                         StartAddress = Address;
499                         Size = 0;
500                         Type = UMA_FREE;
501 
502                         PrevRomAddress = 0;
503                         PrevRomSize = 0;
504                     }
505 
506                     if (*(PUSHORT)REAL_TO_PHYS(Address) == OPTION_ROM_SIGNATURE)
507                     {
508                         /*
509                          * If this is an adapter ROM (Start: C8000, End: E0000),
510                          * its reported size is stored in byte 2 of the ROM.
511                          *
512                          * If this is an expansion ROM (Start: E0000, End: F0000),
513                          * its real length is 64kB.
514                          */
515                         RomSize = *(PUCHAR)REAL_TO_PHYS(Address + 2) * 512;
516                         // if (Address >= 0xE0000) RomSize = 0x10000;
517                         if (Address >= 0xE0000) { RomSize = 0x10000; Increment = RomSize; }
518 
519                         DPRINT1("ROM present @ address 0x%p\n", Address);
520 
521                         if (StartAddress != 0 && Size != 0 &&
522                             StartAddress + Size <= Address)
523                         {
524                             /* Finish old descriptor */
525                             UmaDesc = CreateUmaDescriptor(NULL, StartAddress, Size, Type);
526                             if (!UmaDesc) return FALSE;
527                         }
528 
529                         /*
530                          * We may have overlapping ROMs, when PrevRomAddress + PrevRomSize > RomAddress.
531                          * They must be put inside the same UMA descriptor.
532                          */
533                         if (PrevRomAddress + PrevRomSize > /*Rom*/Address)
534                         {
535                             // Overlapping ROM
536 
537                             /*
538                              * PrevRomAddress remains the same, but adjust
539                              * PrevRomSize (ROM descriptors merging).
540                              */
541                             PrevRomSize = max(PrevRomSize, RomSize + Address - PrevRomAddress);
542 
543                             // FIX: Confirm that the start address is really
544                             // the one of the previous descriptor.
545                             StartAddress = PrevRomAddress;
546                             Size = PrevRomSize;
547                             Type = UMA_ROM;
548                         }
549                         else
550                         {
551                             // Non-overlapping ROM
552 
553                             PrevRomAddress = Address;
554                             PrevRomSize = RomSize;
555 
556                             /* Initialize a new descriptor. We will create it when it's OK */
557                             StartAddress = Address;
558                             Size = RomSize;
559                             Type = UMA_ROM;
560                             // continue;
561                         }
562                     }
563 #if 1 // FIXME: ...or there??
564                     else
565                     {
566                         // We may be looping inside a ROM block, if: Type == 2 and:
567                         // (StartAddress <= Address &&) StartAddress + Size > Address.
568                         // In this case, do nothing (do not increase size either)
569                         // But if we are now outside of a ROM block, then we need
570                         // to create the previous block, and initialize a new empty one!
571                         // (and following the next passages, increase its size).
572 
573                         // if (StartAddress < Address && Type != UMA_ROM)
574                         if (Type == UMA_ROM && StartAddress + Size > Address)
575                         {
576                             // We are inside ROM, do nothing
577                         }
578                         else if (Type == UMA_ROM && StartAddress + Size <= Address)
579                         {
580                             // We finished a ROM descriptor.
581 
582                             /* Create descriptor */
583                             UmaDesc = CreateUmaDescriptor(NULL, StartAddress, Size, Type);
584                             if (!UmaDesc) return FALSE;
585 
586                             StartAddress = 0;
587                             goto Restart;
588                         }
589                         else if (Type != UMA_ROM)
590                         {
591                             Size += Increment;
592                         }
593                     }
594 #endif
595 
596                     // Fixed incroment; we may encounter again overlapping ROMs, etc.
597                     // Address += Increment;
598                 }
599 
600                 if (StartAddress != 0 && Size != 0)
601                 {
602                     /* Create descriptor */
603                     UmaDesc = CreateUmaDescriptor(NULL, StartAddress, Size, Type);
604                     if (!UmaDesc) return FALSE;
605 
606                     StartAddress = 0;
607                 }
608 
609             }
610         }
611     }
612 
613     return TRUE;
614 }
615 
UmaMgrCleanup(VOID)616 VOID UmaMgrCleanup(VOID)
617 {
618     PUMA_DESCRIPTOR UmaDesc;
619 
620     while (!IsListEmpty(&UmaDescriptorList))
621     {
622         UmaDesc = (PUMA_DESCRIPTOR)CONTAINING_RECORD(UmaDescriptorList.Flink, UMA_DESCRIPTOR, Entry);
623         FreeUmaDescriptor(UmaDesc);
624     }
625 }
626 
627 /* EOF */
628