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Diffstat (limited to 'util/reserved-region.c')
| -rw-r--r-- | util/reserved-region.c | 91 |
1 files changed, 91 insertions, 0 deletions
diff --git a/util/reserved-region.c b/util/reserved-region.c new file mode 100644 index 0000000000..18f83eb4c6 --- /dev/null +++ b/util/reserved-region.c @@ -0,0 +1,91 @@ +/* + * QEMU ReservedRegion helpers + * + * Copyright (c) 2023 Red Hat, Inc. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public + * License as published by the Free Software Foundation; either + * version 2 of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, see <http://www.gnu.org/licenses/>. + */ + +#include "qemu/osdep.h" +#include "qemu/range.h" +#include "qemu/reserved-region.h" + +GList *resv_region_list_insert(GList *list, ReservedRegion *reg) +{ + ReservedRegion *resv_iter, *new_reg; + Range *r = ®->range; + Range *range_iter; + GList *l; + + for (l = list; l ; ) { + resv_iter = (ReservedRegion *)l->data; + range_iter = &resv_iter->range; + + /* Skip all list elements strictly less than range to add */ + if (range_compare(range_iter, r) < 0) { + l = l->next; + } else if (range_compare(range_iter, r) > 0) { + return g_list_insert_before(list, l, reg); + } else { /* there is an overlap */ + if (range_contains_range(r, range_iter)) { + /* new range contains current item, simply remove this latter */ + GList *prev = l->prev; + g_free(l->data); + list = g_list_delete_link(list, l); + if (prev) { + l = prev->next; + } else { + l = list; + } + } else if (range_contains_range(range_iter, r)) { + /* new region is included in the current region */ + if (range_lob(range_iter) == range_lob(r)) { + /* adjacent on the left side, derives into 2 regions */ + range_set_bounds(range_iter, range_upb(r) + 1, + range_upb(range_iter)); + return g_list_insert_before(list, l, reg); + } else if (range_upb(range_iter) == range_upb(r)) { + /* adjacent on the right side, derives into 2 regions */ + range_set_bounds(range_iter, range_lob(range_iter), + range_lob(r) - 1); + l = l->next; + } else { + uint64_t lob = range_lob(range_iter); + /* + * the new range is in the middle of an existing one, + * split this latter into 3 regs instead + */ + range_set_bounds(range_iter, range_upb(r) + 1, + range_upb(range_iter)); + new_reg = g_new0(ReservedRegion, 1); + new_reg->type = resv_iter->type; + range_set_bounds(&new_reg->range, + lob, range_lob(r) - 1); + list = g_list_insert_before(list, l, new_reg); + return g_list_insert_before(list, l, reg); + } + } else if (range_lob(r) < range_lob(range_iter)) { + range_set_bounds(range_iter, range_upb(r) + 1, + range_upb(range_iter)); + return g_list_insert_before(list, l, reg); + } else { /* intersection on the upper range */ + range_set_bounds(range_iter, range_lob(range_iter), + range_lob(r) - 1); + l = l->next; + } + } /* overlap */ + } + return g_list_append(list, reg); +} + |