| #include <stdlib.h> |
| |
| #include "kexec.h" |
| #include "mem_regions.h" |
| |
| static int mem_range_cmp(const void *a1, const void *a2) |
| { |
| const struct memory_range *r1 = a1; |
| const struct memory_range *r2 = a2; |
| |
| if (r1->start > r2->start) |
| return 1; |
| if (r1->start < r2->start) |
| return -1; |
| |
| return 0; |
| } |
| |
| /** |
| * mem_regions_sort() - sort ranges into ascending address order |
| * @ranges: ranges to sort |
| * |
| * Sort the memory regions into ascending address order. |
| */ |
| void mem_regions_sort(struct memory_ranges *ranges) |
| { |
| qsort(ranges->ranges, ranges->size, sizeof(*ranges->ranges), |
| mem_range_cmp); |
| } |
| |
| /** |
| * mem_regions_add() - add a memory region to a set of ranges |
| * @ranges: ranges to add the memory region to |
| * @base: base address of memory region |
| * @length: length of memory region in bytes |
| * @type: type of memory region |
| * |
| * Add the memory region to the set of ranges, and return %0 if successful, |
| * or %-1 if we ran out of space. |
| */ |
| int mem_regions_add(struct memory_ranges *ranges, unsigned long long base, |
| unsigned long long length, int type) |
| { |
| struct memory_range *range; |
| |
| if (ranges->size >= ranges->max_size) |
| return -1; |
| |
| range = ranges->ranges + ranges->size++; |
| range->start = base; |
| range->end = base + length - 1; |
| range->type = type; |
| |
| return 0; |
| } |
| |
| static void mem_regions_remove(struct memory_ranges *ranges, int index) |
| { |
| int tail_entries; |
| |
| /* we are assured to have at least one entry */ |
| ranges->size -= 1; |
| |
| /* if we have following entries, shuffle them down one place */ |
| tail_entries = ranges->size - index; |
| if (tail_entries) |
| memmove(ranges->ranges + index, ranges->ranges + index + 1, |
| tail_entries * sizeof(*ranges->ranges)); |
| |
| /* zero the new tail entry */ |
| memset(ranges->ranges + ranges->size, 0, sizeof(*ranges->ranges)); |
| } |
| |
| /** |
| * mem_regions_exclude() - excludes a memory region from a set of memory ranges |
| * @ranges: memory ranges to exclude the region from |
| * @range: memory range to exclude |
| * |
| * Exclude a memory region from a set of memory ranges. We assume that |
| * the region to be excluded is either wholely located within one of the |
| * memory ranges, or not at all. |
| */ |
| int mem_regions_exclude(struct memory_ranges *ranges, |
| const struct memory_range *range) |
| { |
| int i, ret; |
| |
| for (i = 0; i < ranges->size; i++) { |
| struct memory_range *r = ranges->ranges + i; |
| |
| /* |
| * We assume that crash area is fully contained in |
| * some larger memory area. |
| */ |
| if (r->start <= range->start && r->end >= range->end) { |
| if (r->start == range->start) { |
| if (r->end == range->end) |
| /* Remove this entry */ |
| mem_regions_remove(ranges, i); |
| else |
| /* Shrink the start of this memory range */ |
| r->start = range->end + 1; |
| } else if (r->end == range->end) { |
| /* Shrink the end of this memory range */ |
| r->end = range->start - 1; |
| } else { |
| /* |
| * Split this area into 2 smaller ones and |
| * remove excluded range from between. First |
| * create new entry for the remaining area. |
| */ |
| ret = mem_regions_add(ranges, range->end + 1, |
| r->end - range->end, 0); |
| if (ret < 0) |
| return ret; |
| |
| /* |
| * Update this area to end before excluded |
| * range. |
| */ |
| r->end = range->start - 1; |
| break; |
| } |
| } |
| } |
| return 0; |
| } |
| |
| #define KEXEC_MEMORY_RANGES 16 |
| |
| int mem_regions_alloc_and_add(struct memory_ranges *ranges, |
| unsigned long long base, |
| unsigned long long length, int type) |
| { |
| void *new_ranges; |
| |
| if (ranges->size >= ranges->max_size) { |
| new_ranges = realloc(ranges->ranges, |
| sizeof(struct memory_range) * |
| (ranges->max_size + KEXEC_MEMORY_RANGES)); |
| if (!new_ranges) |
| return -1; |
| |
| ranges->ranges = new_ranges; |
| ranges->max_size += KEXEC_MEMORY_RANGES; |
| } |
| |
| return mem_regions_add(ranges, base, length, type); |
| } |
| |
| int mem_regions_alloc_and_exclude(struct memory_ranges *ranges, |
| const struct memory_range *range) |
| { |
| void *new_ranges; |
| |
| /* for safety, we should have at least one free entry in ranges */ |
| if (ranges->size >= ranges->max_size) { |
| new_ranges = realloc(ranges->ranges, |
| sizeof(struct memory_range) * |
| (ranges->max_size + KEXEC_MEMORY_RANGES)); |
| if (!new_ranges) |
| return -1; |
| |
| ranges->ranges = new_ranges; |
| ranges->max_size += KEXEC_MEMORY_RANGES; |
| } |
| |
| return mem_regions_exclude(ranges, range); |
| } |