On Fri, Mar 22, 2013 at 1:54 PM, Yinghai Lu <yinghai at kernel.org> wrote:
> Vivek found specical handling crashkernel low in not good.
> We should extend kexec-tools to handle multiple Crash kernel instead.
>
> Extend crash_reserved_mem to array instead and use
> kexec_iomem_for_each_line directly. After that we can drop
> crashkernel low.
>
> -v2: fix left over calling of parse_iomem_single() found by Vivek.
>
> Suggested-by: Vivek Goyal <vgoyal at redhat.com>
> Signed-off-by: Yinghai Lu <yinghai at kernel.org>
>
> ---
> kexec/arch/i386/crashdump-x86.c | 109 +++++++++++++++++++++----------------
> kexec/arch/i386/kexec-x86-common.c | 4 -
> kexec/kexec.h | 1
> 3 files changed, 66 insertions(+), 48 deletions(-)
>
> Index: kexec-tools/kexec/arch/i386/crashdump-x86.c
> ===================================================================
> --- kexec-tools.orig/kexec/arch/i386/crashdump-x86.c
> +++ kexec-tools/kexec/arch/i386/crashdump-x86.c
> @@ -188,9 +188,9 @@ static int exclude_region(int *nr_ranges
> static struct memory_range crash_memory_range[CRASH_MAX_MEMORY_RANGES];
>
> /* Memory region reserved for storing panic kernel and other data. */
> -static struct memory_range crash_reserved_mem;
> -/* under 4G parts */
> -static struct memory_range crash_reserved_low_mem;
> +#define CRASH_RESERVED_MEM_NR 8
> +static struct memory_range crash_reserved_mem[CRASH_RESERVED_MEM_NR];
> +static int crash_reserved_mem_nr;
>
> /* Reads the appropriate file and retrieves the SYSTEM RAM regions for whom to
> * create Elf headers. Keeping it separate from get_memory_ranges() as
> @@ -207,7 +207,7 @@ static int get_crash_memory_ranges(struc
> int kexec_flags, unsigned long lowmem_limit)
> {
> const char *iomem = proc_iomem();
> - int memory_ranges = 0, gart = 0;
> + int memory_ranges = 0, gart = 0, i;
> char line[MAX_LINE];
> FILE *fp;
> unsigned long long start, end;
> @@ -268,29 +268,28 @@ static int get_crash_memory_ranges(struc
> }
> fclose(fp);
> if (kexec_flags & KEXEC_PRESERVE_CONTEXT) {
> - int i;
> for (i = 0; i < memory_ranges; i++) {
> if (crash_memory_range[i].end > 0x0009ffff) {
> - crash_reserved_mem.start = \
> + crash_reserved_mem[0].start = \
> crash_memory_range[i].start;
> break;
> }
> }
> - if (crash_reserved_mem.start >= mem_max) {
> + if (crash_reserved_mem[0].start >= mem_max) {
> fprintf(stderr, "Too small mem_max: 0x%llx.\n",
> mem_max);
> return -1;
> }
> - crash_reserved_mem.end = mem_max;
> - crash_reserved_mem.type = RANGE_RAM;
> + crash_reserved_mem[0].end = mem_max;
> + crash_reserved_mem[0].type = RANGE_RAM;
> + crash_reserved_mem_nr = 1;
> }
> - if (exclude_region(&memory_ranges, crash_reserved_mem.start,
> - crash_reserved_mem.end) < 0)
> - return -1;
> - if (crash_reserved_low_mem.start &&
> - exclude_region(&memory_ranges, crash_reserved_low_mem.start,
> - crash_reserved_low_mem.end) < 0)
> - return -1;
> +
> + for (i = 0; i < crash_reserved_mem_nr; i++)
> + if (exclude_region(&memory_ranges, crash_reserved_mem[i].start,
> + crash_reserved_mem[i].end) < 0)
> + return -1;
> +
> if (gart) {
> /* exclude GART region if the system has one */
> if (exclude_region(&memory_ranges, gart_start, gart_end) < 0)
> @@ -351,9 +350,10 @@ static int get_crash_memory_ranges_xen(s
>
> qsort(*range, *ranges, sizeof(struct memory_range), compare_ranges);
>
> - if (exclude_region(ranges, crash_reserved_mem.start,
> - crash_reserved_mem.end) < 0)
> - goto err;
> + for (i = 0; i < crash_reserved_mem_nr; i++)
> + if (exclude_region(ranges, crash_reserved_mem[i].start,
> + crash_reserved_mem[i].end) < 0)
> + goto err;
>
> ret = 0;
>
> @@ -434,9 +434,10 @@ static int get_crash_memory_ranges_xen(s
>
> qsort(*range, *ranges, sizeof(struct memory_range), compare_ranges);
>
> - if (exclude_region(ranges, crash_reserved_mem.start,
> - crash_reserved_mem.end) < 0)
> - goto err;
> + for (i = 0; i < crash_reserved_mem_nr; i++)
> + if (exclude_region(ranges, crash_reserved_mem[i].start,
> + crash_reserved_mem[i].end) < 0)
> + goto err;
>
> ret = 0;
>
> @@ -1022,15 +1023,10 @@ int load_crashdump_segments(struct kexec
> memmap_p = xmalloc(sz);
> memset(memmap_p, 0, sz);
> add_memmap(memmap_p, info->backup_src_start, info->backup_src_size);
> - sz = crash_reserved_mem.end - crash_reserved_mem.start +1;
> - if (add_memmap(memmap_p, crash_reserved_mem.start, sz) < 0) {
> - return ENOCRASHKERNEL;
> - }
> -
> - if (crash_reserved_low_mem.start) {
> - sz = crash_reserved_low_mem.end - crash_reserved_low_mem.start
> - +1;
> - add_memmap(memmap_p, crash_reserved_low_mem.start, sz);
> + for (i = 0; i < crash_reserved_mem_nr; i++) {
> + sz = crash_reserved_mem[i].end - crash_reserved_mem[i].start +1;
> + if (add_memmap(memmap_p, crash_reserved_mem[i].start, sz) < 0)
> + return ENOCRASHKERNEL;
> }
>
> /* Create a backup region segment to store backup data*/
> @@ -1101,25 +1097,46 @@ int load_crashdump_segments(struct kexec
> return 0;
> }
>
> -int is_crashkernel_mem_reserved(void)
> +int get_max_crash_kernel_limit(uint64_t *start, uint64_t *end)
> {
> - uint64_t start, end;
> + int i, idx = -1;
> + unsigned long sz_max = 0, sz;
>
> - if (parse_iomem_single("Crash kernel\n", &start, &end) || start == end)
> - return 0;
> + if (!crash_reserved_mem_nr)
> + return -1;
>
> - crash_reserved_mem.start = start;
> - crash_reserved_mem.end = end;
> - crash_reserved_mem.type = RANGE_RAM;
> -
> - /* If there is no Crash low kernel, still can go on */
> - if (parse_iomem_single("Crash kernel low\n", &start, &end) ||
> - start == end)
> + for (i = crash_reserved_mem_nr - 1; i >= 0; i--) {
> + sz = crash_reserved_mem[i].end - crash_reserved_mem[i].start +1;
> + if (sz <= sz_max)
> + continue;
> + sz_max = sz;
> + idx = i;
> + }
> +
> + *start = crash_reserved_mem[idx].start;
> + *end = crash_reserved_mem[idx].end;
> +
> + return 0;
> +}
> +
> +static int crashkernel_mem_callback(void *UNUSED(data), int nr,
> + char *UNUSED(str),
> + unsigned long base,
> + unsigned long length)
> +{
> + if (nr >= CRASH_RESERVED_MEM_NR)
> return 1;
>
> - crash_reserved_low_mem.start = start;
> - crash_reserved_low_mem.end = end;
> - crash_reserved_low_mem.type = RANGE_RAM;
> + crash_reserved_mem[nr].start = base;
> + crash_reserved_mem[nr].end = base + length - 1;
> + crash_reserved_mem[nr].type = RANGE_RAM;
> + return 0;
> +}
> +
> +int is_crashkernel_mem_reserved(void)
> +{
> + crash_reserved_mem_nr = kexec_iomem_for_each_line("Crash kernel\n",
> + crashkernel_mem_callback, NULL);
>
> - return 1;
> + return !!crash_reserved_mem_nr;
> }
> Index: kexec-tools/kexec/arch/i386/kexec-x86-common.c
> ===================================================================
> --- kexec-tools.orig/kexec/arch/i386/kexec-x86-common.c
> +++ kexec-tools/kexec/arch/i386/kexec-x86-common.c
> @@ -465,9 +465,9 @@ int get_memory_ranges(struct memory_rang
> !(kexec_flags & KEXEC_PRESERVE_CONTEXT)) {
> uint64_t start, end;
>
> - ret = parse_iomem_single("Crash kernel\n", &start, &end);
> + ret = get_max_crash_kernel_limit(&start, &end);
> if (ret != 0) {
> - fprintf(stderr, "parse_iomem_single failed.\n");
> + fprintf(stderr, "get_max_crash_kernel_limit failed.\n");
> return -1;
> }
>
> Index: kexec-tools/kexec/kexec.h
> ===================================================================
> --- kexec-tools.orig/kexec/kexec.h
> +++ kexec-tools/kexec/kexec.h
> @@ -272,6 +272,7 @@ int arch_process_options(int argc, char
> int arch_compat_trampoline(struct kexec_info *info);
> void arch_update_purgatory(struct kexec_info *info);
> int is_crashkernel_mem_reserved(void);
> +int get_max_crash_kernel_limit(uint64_t *start, uint64_t *end);
> char *get_command_line(void);
>
> int kexec_iomem_for_each_line(char *match,
Simon,
Can you pick up this one?
Related change in kernel has been merged to upsteam via hpa.
https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=157752d84f5df47e01577970f9c5f61a0b9f4546
Thanks
Yinghai
