1 files changed, 433 insertions, 0 deletions
diff --git a/kexec/arch/ppc/crashdump-powerpc.c b/kexec/arch/ppc/crashdump-powerpc.c
new file mode 100644
index 0000000..15e8531
--- /dev/null
+++ b/kexec/arch/ppc/crashdump-powerpc.c
@@ -0,0 +1,433 @@
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <errno.h>
+#include <limits.h>
+#include <elf.h>
+#include <dirent.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include "../../kexec.h"
+#include "../../kexec-elf.h"
+#include "../../kexec-syscall.h"
+#include "../../crashdump.h"
+#include "kexec-ppc.h"
+#include "crashdump-powerpc.h"
+
+#define DEVTREE_CRASHKERNEL_BASE "/proc/device-tree/chosen/linux,crashkernel-base"
+#define DEVTREE_CRASHKERNEL_SIZE "/proc/device-tree/chosen/linux,crashkernel-size"
+
+#ifdef CONFIG_PPC64
+static struct crash_elf_info elf_info64 = {
+class: ELFCLASS64,
+data: ELFDATA2MSB,
+machine: EM_PPC64,
+page_offset: PAGE_OFFSET,
+lowmem_limit: MAXMEM,
+};
+#endif
+static struct crash_elf_info elf_info32 = {
+class: ELFCLASS32,
+data: ELFDATA2MSB,
+#ifdef CONFIG_PPC64
+machine: EM_PPC64,
+#else
+machine: EM_PPC,
+#endif
+page_offset: PAGE_OFFSET,
+lowmem_limit: MAXMEM,
+};
+
+/* Stores a sorted list of RAM memory ranges for which to create elf headers.
+ * A separate program header is created for backup region
+ */
+static struct memory_range *crash_memory_range;
+static int crash_nr_memory_ranges;
+
+/* Define a variable to replace the CRASH_MAX_MEMORY_RANGES macro */
+static int crash_max_memory_ranges;
+
+/*
+ * Used to save various memory ranges/regions needed for the captured
+ * kernel to boot. (lime memmap= option in other archs)
+ */
+mem_rgns_t usablemem_rgns = {0, NULL};
+
+/* Append a segment to crash_memory_range, splitting it into two if
+ * it contains both lowmem and highmem */
+static void add_crash_memory_range(unsigned long long start,
+		unsigned long long end)
+{
+#ifndef CONFIG_PPC64
+	if (start < elf_info32.lowmem_limit && end > elf_info32.lowmem_limit) {
+		add_crash_memory_range(start, elf_info32.lowmem_limit);
+		add_crash_memory_range(elf_info32.lowmem_limit, end);
+		return;
+	}
+#endif
+
+	if (crash_nr_memory_ranges < crash_max_memory_ranges) {
+		crash_memory_range[crash_nr_memory_ranges].start = start;
+		crash_memory_range[crash_nr_memory_ranges].end = end;
+		crash_memory_range[crash_nr_memory_ranges].type = RANGE_RAM;
+	}
+
+	crash_nr_memory_ranges++;
+}
+
+
+/* Reads the appropriate file and retrieves the SYSTEM RAM regions for whom to
+ * create Elf headers. Keeping it separate from get_memory_ranges() as
+ * requirements are different in the case of normal kexec and crashdumps.
+ *
+ * Normal kexec needs to look at all of available physical memory irrespective
+ * of the fact how much of it is being used by currently running kernel.
+ * Crashdumps need to have access to memory regions actually being used by
+ * running  kernel. Expecting a different file/data structure than /proc/iomem
+ * to look into down the line. May be something like /proc/kernelmem or may
+ * be zone data structures exported from kernel.
+ */
+static int get_crash_memory_ranges(struct memory_range **range, int *ranges)
+{
+
+	char device_tree[256] = "/proc/device-tree/";
+	char fname[256];
+	DIR *dir, *dmem;
+	int fd;
+	struct dirent *dentry, *mentry;
+	int n, crash_rng_len = 0;
+	unsigned long long start, end, cstart, cend;
+
+	crash_max_memory_ranges = max_memory_ranges + 6;
+	crash_rng_len = sizeof(struct memory_range) * crash_max_memory_ranges;
+
+	crash_memory_range = (struct memory_range *) malloc(crash_rng_len);
+	if (!crash_memory_range) {
+		fprintf(stderr, "Allocation for crash memory range failed\n");
+		return -1;
+	}
+	memset(crash_memory_range, 0, crash_rng_len);
+	crash_nr_memory_ranges = 0;
+
+#ifndef CONFIG_BOOKE
+	/* create a separate program header for the backup region */
+	add_crash_memory_range(BACKUP_SRC_START, BACKUP_SRC_END + 1);
+#endif
+
+	dir = opendir(device_tree);
+	if (!dir) {
+		perror(device_tree);
+		goto err;
+	}
+	while ((dentry = readdir(dir)) != NULL) {
+		if (strncmp(dentry->d_name, "memory@", 7)
+		    && strcmp(dentry->d_name, "memory"))
+			continue;
+		strcpy(fname, device_tree);
+		strcat(fname, dentry->d_name);
+		dmem = opendir(fname);
+		if (!dmem) {
+			perror(fname);
+			closedir(dir);
+			goto err;
+		}
+		while ((mentry = readdir(dmem)) != NULL) {
+			if (strcmp(mentry->d_name, "reg"))
+				continue;
+			strcat(fname, "/reg");
+			fd = open(fname, O_RDONLY);
+			if (fd < 0) {
+				perror(fname);
+				closedir(dmem);
+				closedir(dir);
+				goto err;
+			}
+			n = read_memory_region_limits(fd, &start, &end);
+			/* We are done with fd, close it. */
+			close(fd);
+			if (n != 0) {
+				closedir(dmem);
+				closedir(dir);
+				goto err;
+			}
+#ifndef CONFIG_BOOKE
+			if (start == 0 && end >= (BACKUP_SRC_END + 1))
+				start = BACKUP_SRC_END + 1;
+#endif
+
+			/*
+			 * Exclude the region that lies within crashkernel.
+			 * If memory limit is set then exclude memory region
+			 * above it.
+			 */
+
+			if (memory_limit) {
+				if (start >= memory_limit)
+					continue;
+				if (end > memory_limit)
+					end = memory_limit;
+			}
+
+			/*
+			 * Exclure region used by crash kernel
+			 */
+			cstart = crash_base;
+			cend = crash_base + crash_size;
+
+			if (cstart >= end || cend <= start)
+				add_crash_memory_range(start, end);
+			else {
+				if (start < cstart)
+					add_crash_memory_range(start, cstart);
+				if (cend < end)
+					add_crash_memory_range(cend, end);
+			}
+		}
+		closedir(dmem);
+	}
+	closedir(dir);
+
+	/*
+	 * If RTAS region is overlapped with crashkernel, need to create ELF
+	 * Program header for the overlapped memory.
+	 */
+	if (crash_base < rtas_base + rtas_size &&
+		rtas_base < crash_base + crash_size) {
+		cstart = rtas_base;
+		cend = rtas_base + rtas_size;
+		if (cstart < crash_base)
+			cstart = crash_base;
+		if (cend > crash_base + crash_size)
+			cend = crash_base + crash_size;
+		add_crash_memory_range(cstart, cend);
+	}
+
+	if (crash_nr_memory_ranges >= crash_max_memory_ranges) {
+		fprintf(stderr,
+			"Error: Number of crash memory ranges"
+			" excedeed the max limit\n");
+		goto err;
+	}
+
+	*range = crash_memory_range;
+	*ranges = crash_nr_memory_ranges;
+
+	int j;
+	dbgprintf("CRASH MEMORY RANGES\n");
+	for (j = 0; j < *ranges; j++) {
+		start = crash_memory_range[j].start;
+		end = crash_memory_range[j].end;
+		dbgprintf("%016Lx-%016Lx\n", start, end);
+	}
+
+	return 0;
+
+err:
+	if (crash_memory_range)
+		free(crash_memory_range);
+	return -1;
+}
+
+/* Converts unsigned long to ascii string. */
+static void ulltoa(unsigned long long i, char *str)
+{
+	int j = 0, k;
+	char tmp;
+
+	do {
+		str[j++] = i % 10 + '0';
+	} while ((i /= 10) > 0);
+	str[j] = '\0';
+
+	/* Reverse the string. */
+	for (j = 0, k = strlen(str) - 1; j < k; j++, k--) {
+		tmp = str[k];
+		str[k] = str[j];
+		str[j] = tmp;
+	}
+}
+
+/* Append str to cmdline */
+static void add_cmdline(char *cmdline, char *str)
+{
+	int cmdline_size;
+	int cmdlen = strlen(cmdline) + strlen(str);
+
+	cmdline_size = COMMAND_LINE_SIZE;
+	if (cmdlen > (cmdline_size - 1))
+		die("Command line overflow\n");
+	strcat(cmdline, str);
+}
+
+static int add_cmdline_param(char *cmdline, unsigned long long addr,
+				char *cmdstr, char *byte)
+{
+	int align = 1024;
+	char str[COMMAND_LINE_SIZE], *ptr;
+
+	/* Passing in =xxxK / =xxxM format. Saves space required in cmdline.*/
+	switch (byte[0]) {
+	case 'K':
+		if (addr%align)
+			return -1;
+		addr = addr/align;
+		break;
+	case 'M':
+		addr = addr/(align *align);
+		break;
+	}
+	ptr = str;
+	strcpy(str, cmdstr);
+	ptr += strlen(str);
+	ulltoa(addr, ptr);
+	strcat(str, byte);
+
+	add_cmdline(cmdline, str);
+
+	dbgprintf("Command line after adding elfcorehdr: %s\n", cmdline);
+
+	return 0;
+}
+
+/* Loads additional segments in case of a panic kernel is being loaded.
+ * One segment for backup region, another segment for storing elf headers
+ * for crash memory image.
+ */
+int load_crashdump_segments(struct kexec_info *info, char *mod_cmdline,
+				unsigned long max_addr, unsigned long min_base)
+{
+	void *tmp;
+	unsigned long sz, elfcorehdr;
+	int nr_ranges, align = 1024, i;
+	unsigned long long end;
+	struct memory_range *mem_range;
+
+	if (get_crash_memory_ranges(&mem_range, &nr_ranges) < 0)
+		return -1;
+
+	info->backup_src_start = BACKUP_SRC_START;
+	info->backup_src_size = BACKUP_SRC_SIZE;
+#ifndef CONFIG_BOOKE
+	/* Create a backup region segment to store backup data*/
+	sz = _ALIGN(BACKUP_SRC_SIZE, align);
+	tmp = xmalloc(sz);
+	memset(tmp, 0, sz);
+	info->backup_start = add_buffer(info, tmp, sz, sz, align,
+					0, max_addr, 1);
+	reserve(info->backup_start, sz);
+#endif
+
+	/* On powerpc memory ranges in device-tree is denoted as start
+	 * and size rather than start and end, as is the case with
+	 * other architectures like i386 . Because of this when loading
+	 * the memory ranges in crashdump-elf.c the filesz calculation
+	 * [ end - start + 1 ] goes for a toss.
+	 *
+	 * To be in sync with other archs adjust the end value for
+	 * every crash memory range before calling the generic function
+	 */
+
+	for (i = 0; i < nr_ranges; i++) {
+		end = crash_memory_range[i].end - 1;
+		crash_memory_range[i].end = end;
+	}
+
+
+#ifdef CONFIG_PPC64
+	/* Create elf header segment and store crash image data. */
+	if (arch_options.core_header_type == CORE_TYPE_ELF64) {
+		if (crash_create_elf64_headers(info, &elf_info64,
+					crash_memory_range, nr_ranges, &tmp,
+					&sz, ELF_CORE_HEADER_ALIGN) < 0)
+			return -1;
+	} else if (crash_create_elf32_headers(info, &elf_info32,
+				crash_memory_range, nr_ranges, &tmp, &sz,
+				ELF_CORE_HEADER_ALIGN) < 0)
+			return -1;
+#else
+	if (crash_create_elf32_headers(info, &elf_info32, crash_memory_range,
+				nr_ranges, &tmp, &sz, ELF_CORE_HEADER_ALIGN)
+			< 0)
+		return -1;
+#endif
+
+	elfcorehdr = add_buffer(info, tmp, sz, sz, align,
+			min_base, max_addr, 1);
+	reserve(elfcorehdr, sz);
+	/* modify and store the cmdline in a global array. This is later
+	 * read by flatten_device_tree and modified if required
+	 */
+	add_cmdline_param(mod_cmdline, elfcorehdr, " elfcorehdr=", "K");
+	add_cmdline(mod_cmdline, " maxcpus=1");
+	return 0;
+}
+
+/*
+ * Used to save various memory regions needed for the captured kernel.
+ */
+
+void add_usable_mem_rgns(unsigned long long base, unsigned long long size)
+{
+	int i;
+	unsigned long long end = base + size;
+	unsigned long long ustart, uend;
+
+	base = _ALIGN_DOWN(base, getpagesize());
+	end = _ALIGN_UP(end, getpagesize());
+
+	for (i = 0; i < usablemem_rgns.size; i++) {
+		ustart = usablemem_rgns.ranges[i].start;
+		uend = usablemem_rgns.ranges[i].end;
+		if (base < uend && end > ustart) {
+			if ((base >= ustart) && (end <= uend))
+				return;
+			if (base < ustart && end > uend) {
+				usablemem_rgns.ranges[i].start = base;
+				usablemem_rgns.ranges[i].end = end;
+				return;
+			} else if (base < ustart) {
+				usablemem_rgns.ranges[i].start = base;
+				return;
+			} else if (end > uend) {
+				usablemem_rgns.ranges[i].end = end;
+				return;
+			}
+		}
+	}
+	usablemem_rgns.ranges[usablemem_rgns.size].start = base;
+	usablemem_rgns.ranges[usablemem_rgns.size++].end = end;
+
+	dbgprintf("usable memory rgns size:%u base:%llx size:%llx\n",
+		usablemem_rgns.size, base, size);
+}
+
+int get_crash_kernel_load_range(uint64_t *start, uint64_t *end)
+{
+	unsigned long long value;
+
+	if (!get_devtree_value(DEVTREE_CRASHKERNEL_BASE, &value))
+		*start = value;
+	else
+		return -1;
+
+	if (!get_devtree_value(DEVTREE_CRASHKERNEL_SIZE, &value))
+		*end = *start + value - 1;
+	else
+		return -1;
+
+	return 0;
+}
+
+int is_crashkernel_mem_reserved(void)
+{
+	int fd;
+
+	fd = open(DEVTREE_CRASHKERNEL_BASE, O_RDONLY);
+	if (fd < 0)
+		return 0;
+	close(fd);
+	return 1;
+}
+