| 1 | /* subr_rmap.c 3.1 %H% */ |
| 2 | |
| 3 | #include "../h/param.h" |
| 4 | #include "../h/systm.h" |
| 5 | #include "../h/map.h" |
| 6 | #include "../h/dir.h" |
| 7 | #include "../h/user.h" |
| 8 | #include "../h/proc.h" |
| 9 | #include "../h/mtpr.h" |
| 10 | #include "../h/text.h" |
| 11 | |
| 12 | /* |
| 13 | * Allocate 'size' units from the given |
| 14 | * map. Return the base of the allocated |
| 15 | * space. |
| 16 | * In a map, the addresses are increasing and the |
| 17 | * list is terminated by a 0 size. |
| 18 | * The swap map unit is 512 bytes. |
| 19 | * Algorithm is first-fit. |
| 20 | */ |
| 21 | malloc(mp, size) |
| 22 | struct map *mp; |
| 23 | { |
| 24 | register int a; |
| 25 | register struct map *bp; |
| 26 | |
| 27 | if (size <= 0) |
| 28 | panic("malloc"); |
| 29 | for (bp=mp; bp->m_size; bp++) { |
| 30 | if (bp->m_size >= size) { |
| 31 | a = bp->m_addr; |
| 32 | bp->m_addr += size; |
| 33 | if ((bp->m_size -= size) == 0) { |
| 34 | do { |
| 35 | bp++; |
| 36 | (bp-1)->m_addr = bp->m_addr; |
| 37 | } while ((bp-1)->m_size = bp->m_size); |
| 38 | } |
| 39 | if (mp == swapmap && a % CLSIZE) |
| 40 | panic("malloc swapmap"); |
| 41 | return(a); |
| 42 | } |
| 43 | } |
| 44 | return(0); |
| 45 | } |
| 46 | |
| 47 | /* |
| 48 | * Free the previously allocated space aa |
| 49 | * of size units into the specified map. |
| 50 | * Sort aa into map and combine on |
| 51 | * one or both ends if possible. |
| 52 | */ |
| 53 | mfree(mp, size, a) |
| 54 | struct map *mp; |
| 55 | register int size, a; |
| 56 | { |
| 57 | register struct map *bp; |
| 58 | register int t; |
| 59 | |
| 60 | if (a <= 0) |
| 61 | panic("mfree addr"); |
| 62 | if (size <= 0) |
| 63 | panic("mfree size"); |
| 64 | bp = mp; |
| 65 | for (; bp->m_addr<=a && bp->m_size!=0; bp++) |
| 66 | continue; |
| 67 | if (bp>mp && (bp-1)->m_addr+(bp-1)->m_size > a) |
| 68 | panic("mfree begov"); |
| 69 | if (a+size > bp->m_addr && bp->m_size) |
| 70 | panic("mfree endov"); |
| 71 | if (bp>mp && (bp-1)->m_addr+(bp-1)->m_size == a) { |
| 72 | (bp-1)->m_size += size; |
| 73 | if (a+size == bp->m_addr) { |
| 74 | (bp-1)->m_size += bp->m_size; |
| 75 | while (bp->m_size) { |
| 76 | bp++; |
| 77 | (bp-1)->m_addr = bp->m_addr; |
| 78 | (bp-1)->m_size = bp->m_size; |
| 79 | } |
| 80 | } |
| 81 | } else { |
| 82 | if (a+size == bp->m_addr && bp->m_size) { |
| 83 | bp->m_addr -= size; |
| 84 | bp->m_size += size; |
| 85 | } else if (size) { |
| 86 | do { |
| 87 | t = bp->m_addr; |
| 88 | bp->m_addr = a; |
| 89 | a = t; |
| 90 | t = bp->m_size; |
| 91 | bp->m_size = size; |
| 92 | bp++; |
| 93 | } while (size = t); |
| 94 | } |
| 95 | } |
| 96 | if ((mp == kernelmap) && kmapwnt) { |
| 97 | kmapwnt = 0; |
| 98 | wakeup((caddr_t)kernelmap); |
| 99 | } |
| 100 | } |