diff options
| -rw-r--r-- | kernel/resource.c | 58 |
1 files changed, 50 insertions, 8 deletions
diff --git a/kernel/resource.c b/kernel/resource.c index 14777afb0a99..235dc77f8add 100644 --- a/kernel/resource.c +++ b/kernel/resource.c @@ -540,20 +540,62 @@ static int __region_intersects(struct resource *parent, resource_size_t start, size_t size, unsigned long flags, unsigned long desc) { - struct resource res; + resource_size_t ostart, oend; int type = 0; int other = 0; - struct resource *p; + struct resource *p, *dp; + bool is_type, covered; + struct resource res; res.start = start; res.end = start + size - 1; for (p = parent->child; p ; p = p->sibling) { - bool is_type = (((p->flags & flags) == flags) && - ((desc == IORES_DESC_NONE) || - (desc == p->desc))); - - if (resource_overlaps(p, &res)) - is_type ? type++ : other++; + if (!resource_overlaps(p, &res)) + continue; + is_type = (p->flags & flags) == flags && + (desc == IORES_DESC_NONE || desc == p->desc); + if (is_type) { + type++; + continue; + } + /* + * Continue to search in descendant resources as if the + * matched descendant resources cover some ranges of 'p'. + * + * |------------- "CXL Window 0" ------------| + * |-- "System RAM" --| + * + * will behave similar as the following fake resource + * tree when searching "System RAM". + * + * |-- "System RAM" --||-- "CXL Window 0a" --| + */ + covered = false; + ostart = max(res.start, p->start); + oend = min(res.end, p->end); + for_each_resource(p, dp, false) { + if (!resource_overlaps(dp, &res)) + continue; + is_type = (dp->flags & flags) == flags && + (desc == IORES_DESC_NONE || desc == dp->desc); + if (is_type) { + type++; + /* + * Range from 'ostart' to 'dp->start' + * isn't covered by matched resource. + */ + if (dp->start > ostart) + break; + if (dp->end >= oend) { + covered = true; + break; + } + /* Remove covered range */ + ostart = max(ostart, dp->end + 1); + } + } + if (!covered) + other++; } if (type == 0) |