--- /dev/null
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * powerpc code to implement the kexec_file_load syscall
+ *
+ * Copyright (C) 2004 Adam Litke (agl@us.ibm.com)
+ * Copyright (C) 2004 IBM Corp.
+ * Copyright (C) 2004,2005 Milton D Miller II, IBM Corporation
+ * Copyright (C) 2005 R Sharada (sharada@in.ibm.com)
+ * Copyright (C) 2006 Mohan Kumar M (mohan@in.ibm.com)
+ * Copyright (C) 2020 IBM Corporation
+ *
+ * Based on kexec-tools' kexec-ppc64.c, fs2dt.c.
+ * Heavily modified for the kernel by
+ * Hari Bathini, IBM Corporation.
+ */
+
+#define pr_fmt(fmt) "kexec ranges: " fmt
+
+#include <linux/sort.h>
+#include <linux/kexec.h>
+#include <linux/of_device.h>
+#include <linux/slab.h>
+#include <asm/sections.h>
+#include <asm/kexec_ranges.h>
+
+/**
+ * get_max_nr_ranges - Get the max no. of ranges crash_mem structure
+ * could hold, given the size allocated for it.
+ * @size: Allocation size of crash_mem structure.
+ *
+ * Returns the maximum no. of ranges.
+ */
+static inline unsigned int get_max_nr_ranges(size_t size)
+{
+ return ((size - sizeof(struct crash_mem)) /
+ sizeof(struct crash_mem_range));
+}
+
+/**
+ * get_mem_rngs_size - Get the allocated size of mem_rngs based on
+ * max_nr_ranges and chunk size.
+ * @mem_rngs: Memory ranges.
+ *
+ * Returns the maximum size of @mem_rngs.
+ */
+static inline size_t get_mem_rngs_size(struct crash_mem *mem_rngs)
+{
+ size_t size;
+
+ if (!mem_rngs)
+ return 0;
+
+ size = (sizeof(struct crash_mem) +
+ (mem_rngs->max_nr_ranges * sizeof(struct crash_mem_range)));
+
+ /*
+ * Memory is allocated in size multiple of MEM_RANGE_CHUNK_SZ.
+ * So, align to get the actual length.
+ */
+ return ALIGN(size, MEM_RANGE_CHUNK_SZ);
+}
+
+/**
+ * __add_mem_range - add a memory range to memory ranges list.
+ * @mem_ranges: Range list to add the memory range to.
+ * @base: Base address of the range to add.
+ * @size: Size of the memory range to add.
+ *
+ * (Re)allocates memory, if needed.
+ *
+ * Returns 0 on success, negative errno on error.
+ */
+static int __add_mem_range(struct crash_mem **mem_ranges, u64 base, u64 size)
+{
+ struct crash_mem *mem_rngs = *mem_ranges;
+
+ if (!mem_rngs || (mem_rngs->nr_ranges == mem_rngs->max_nr_ranges)) {
+ mem_rngs = realloc_mem_ranges(mem_ranges);
+ if (!mem_rngs)
+ return -ENOMEM;
+ }
+
+ mem_rngs->ranges[mem_rngs->nr_ranges].start = base;
+ mem_rngs->ranges[mem_rngs->nr_ranges].end = base + size - 1;
+ pr_debug("Added memory range [%#016llx - %#016llx] at index %d\n",
+ base, base + size - 1, mem_rngs->nr_ranges);
+ mem_rngs->nr_ranges++;
+ return 0;
+}
+
+/**
+ * __merge_memory_ranges - Merges the given memory ranges list.
+ * @mem_rngs: Range list to merge.
+ *
+ * Assumes a sorted range list.
+ *
+ * Returns nothing.
+ */
+static void __merge_memory_ranges(struct crash_mem *mem_rngs)
+{
+ struct crash_mem_range *ranges;
+ int i, idx;
+
+ if (!mem_rngs)
+ return;
+
+ idx = 0;
+ ranges = &(mem_rngs->ranges[0]);
+ for (i = 1; i < mem_rngs->nr_ranges; i++) {
+ if (ranges[i].start <= (ranges[i-1].end + 1))
+ ranges[idx].end = ranges[i].end;
+ else {
+ idx++;
+ if (i == idx)
+ continue;
+
+ ranges[idx] = ranges[i];
+ }
+ }
+ mem_rngs->nr_ranges = idx + 1;
+}
+
+/* cmp_func_t callback to sort ranges with sort() */
+static int rngcmp(const void *_x, const void *_y)
+{
+ const struct crash_mem_range *x = _x, *y = _y;
+
+ if (x->start > y->start)
+ return 1;
+ if (x->start < y->start)
+ return -1;
+ return 0;
+}
+
+/**
+ * sort_memory_ranges - Sorts the given memory ranges list.
+ * @mem_rngs: Range list to sort.
+ * @merge: If true, merge the list after sorting.
+ *
+ * Returns nothing.
+ */
+void sort_memory_ranges(struct crash_mem *mem_rngs, bool merge)
+{
+ int i;
+
+ if (!mem_rngs)
+ return;
+
+ /* Sort the ranges in-place */
+ sort(&(mem_rngs->ranges[0]), mem_rngs->nr_ranges,
+ sizeof(mem_rngs->ranges[0]), rngcmp, NULL);
+
+ if (merge)
+ __merge_memory_ranges(mem_rngs);
+
+ /* For debugging purpose */
+ pr_debug("Memory ranges:\n");
+ for (i = 0; i < mem_rngs->nr_ranges; i++) {
+ pr_debug("\t[%03d][%#016llx - %#016llx]\n", i,
+ mem_rngs->ranges[i].start,
+ mem_rngs->ranges[i].end);
+ }
+}
+
+/**
+ * realloc_mem_ranges - reallocate mem_ranges with size incremented
+ * by MEM_RANGE_CHUNK_SZ. Frees up the old memory,
+ * if memory allocation fails.
+ * @mem_ranges: Memory ranges to reallocate.
+ *
+ * Returns pointer to reallocated memory on success, NULL otherwise.
+ */
+struct crash_mem *realloc_mem_ranges(struct crash_mem **mem_ranges)
+{
+ struct crash_mem *mem_rngs = *mem_ranges;
+ unsigned int nr_ranges;
+ size_t size;
+
+ size = get_mem_rngs_size(mem_rngs);
+ nr_ranges = mem_rngs ? mem_rngs->nr_ranges : 0;
+
+ size += MEM_RANGE_CHUNK_SZ;
+ mem_rngs = krealloc(*mem_ranges, size, GFP_KERNEL);
+ if (!mem_rngs) {
+ kfree(*mem_ranges);
+ *mem_ranges = NULL;
+ return NULL;
+ }
+
+ mem_rngs->nr_ranges = nr_ranges;
+ mem_rngs->max_nr_ranges = get_max_nr_ranges(size);
+ *mem_ranges = mem_rngs;
+
+ return mem_rngs;
+}
+
+/**
+ * add_mem_range - Updates existing memory range, if there is an overlap.
+ * Else, adds a new memory range.
+ * @mem_ranges: Range list to add the memory range to.
+ * @base: Base address of the range to add.
+ * @size: Size of the memory range to add.
+ *
+ * (Re)allocates memory, if needed.
+ *
+ * Returns 0 on success, negative errno on error.
+ */
+int add_mem_range(struct crash_mem **mem_ranges, u64 base, u64 size)
+{
+ struct crash_mem *mem_rngs = *mem_ranges;
+ u64 mstart, mend, end;
+ unsigned int i;
+
+ if (!size)
+ return 0;
+
+ end = base + size - 1;
+
+ if (!mem_rngs || !(mem_rngs->nr_ranges))
+ return __add_mem_range(mem_ranges, base, size);
+
+ for (i = 0; i < mem_rngs->nr_ranges; i++) {
+ mstart = mem_rngs->ranges[i].start;
+ mend = mem_rngs->ranges[i].end;
+ if (base < mend && end > mstart) {
+ if (base < mstart)
+ mem_rngs->ranges[i].start = base;
+ if (end > mend)
+ mem_rngs->ranges[i].end = end;
+ return 0;
+ }
+ }
+
+ return __add_mem_range(mem_ranges, base, size);
+}
projects / platform / kernel / linux-rpi.git / commitdiff