| 1 | /* |
| 2 | * QEMU ReservedRegion helpers |
| 3 | * |
| 4 | * Copyright (c) 2023 Red Hat, Inc. |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or |
| 7 | * modify it under the terms of the GNU General Public |
| 8 | * License as published by the Free Software Foundation; either |
| 9 | * version 2 of the License, or (at your option) any later version. |
| 10 | * |
| 11 | * This program is distributed in the hope that it will be useful, |
| 12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 14 | * General Public License for more details. |
| 15 | * |
| 16 | * You should have received a copy of the GNU General Public License |
| 17 | * along with this program; if not, see <http://www.gnu.org/licenses/>. |
| 18 | */ |
| 19 | |
| 20 | #include "qemu/osdep.h" |
| 21 | #include "qemu/range.h" |
| 22 | #include "qemu/reserved-region.h" |
| 23 | |
| 24 | GList *resv_region_list_insert(GList *list, ReservedRegion *reg) |
| 25 | { |
| 26 | ReservedRegion *resv_iter, *new_reg; |
| 27 | Range *r = ®->range; |
| 28 | Range *range_iter; |
| 29 | GList *l; |
| 30 | |
| 31 | for (l = list; l ; ) { |
| 32 | resv_iter = (ReservedRegion *)l->data; |
| 33 | range_iter = &resv_iter->range; |
| 34 | |
| 35 | /* Skip all list elements strictly less than range to add */ |
| 36 | if (range_compare(range_iter, r) < 0) { |
| 37 | l = l->next; |
| 38 | } else if (range_compare(range_iter, r) > 0) { |
| 39 | return g_list_insert_before(list, l, reg); |
| 40 | } else { /* there is an overlap */ |
| 41 | if (range_contains_range(r, range_iter)) { |
| 42 | /* new range contains current item, simply remove this latter */ |
| 43 | GList *prev = l->prev; |
| 44 | g_free(l->data); |
| 45 | list = g_list_delete_link(list, l); |
| 46 | if (prev) { |
| 47 | l = prev->next; |
| 48 | } else { |
| 49 | l = list; |
| 50 | } |
| 51 | } else if (range_contains_range(range_iter, r)) { |
| 52 | /* new region is included in the current region */ |
| 53 | if (range_lob(range_iter) == range_lob(r)) { |
| 54 | /* adjacent on the left side, derives into 2 regions */ |
| 55 | range_set_bounds(range_iter, range_upb(r) + 1, |
| 56 | range_upb(range_iter)); |
| 57 | return g_list_insert_before(list, l, reg); |
| 58 | } else if (range_upb(range_iter) == range_upb(r)) { |
| 59 | /* adjacent on the right side, derives into 2 regions */ |
| 60 | range_set_bounds(range_iter, range_lob(range_iter), |
| 61 | range_lob(r) - 1); |
| 62 | l = l->next; |
| 63 | } else { |
| 64 | uint64_t lob = range_lob(range_iter); |
| 65 | /* |
| 66 | * the new range is in the middle of an existing one, |
| 67 | * split this latter into 3 regs instead |
| 68 | */ |
| 69 | range_set_bounds(range_iter, range_upb(r) + 1, |
| 70 | range_upb(range_iter)); |
| 71 | new_reg = g_new0(ReservedRegion, 1); |
| 72 | new_reg->type = resv_iter->type; |
| 73 | range_set_bounds(&new_reg->range, |
| 74 | lob, range_lob(r) - 1); |
| 75 | list = g_list_insert_before(list, l, new_reg); |
| 76 | return g_list_insert_before(list, l, reg); |
| 77 | } |
| 78 | } else if (range_lob(r) < range_lob(range_iter)) { |
| 79 | range_set_bounds(range_iter, range_upb(r) + 1, |
| 80 | range_upb(range_iter)); |
| 81 | return g_list_insert_before(list, l, reg); |
| 82 | } else { /* intersection on the upper range */ |
| 83 | range_set_bounds(range_iter, range_lob(range_iter), |
| 84 | range_lob(r) - 1); |
| 85 | l = l->next; |
| 86 | } |
| 87 | } /* overlap */ |
| 88 | } |
| 89 | return g_list_append(list, reg); |
| 90 | } |
| 91 |