On Tue, May 3, 2016 at 3:53 PM, Russell King <rmk at arm.linux.org.uk> wrote:
> Add support for reserving multiple memory regions rather than just a
> single region.
>
> Signed-off-by: Russell King <rmk at arm.linux.org.uk>
Reviewed-by: Pratyush Anand <panand at redhat.com>
> ---
> kexec/arch/arm/crashdump-arm.c | 66 ++++++++++++++++--------------------------
> 1 file changed, 25 insertions(+), 41 deletions(-)
>
> diff --git a/kexec/arch/arm/crashdump-arm.c b/kexec/arch/arm/crashdump-arm.c
> index 1a6ab88..9113f5e 100644
> --- a/kexec/arch/arm/crashdump-arm.c
> +++ b/kexec/arch/arm/crashdump-arm.c
> @@ -55,6 +55,14 @@ struct memory_ranges usablemem_rgns = {
> /* memory range reserved for crashkernel */
> static struct memory_range crash_kernel_mem;
>
> +/* reserved regions */
> +#define CRASH_MAX_RESERVED_RANGES 2
> +static struct memory_range crash_reserved_ranges[CRASH_MAX_RESERVED_RANGES];
> +static struct memory_ranges crash_reserved_rgns = {
> + .max_size = CRASH_MAX_RESERVED_RANGES,
> + .ranges = crash_reserved_ranges,
> +};
> +
> static struct crash_elf_info elf_info = {
> .class = ELFCLASS32,
> .data = ELFDATANATIVE,
> @@ -133,44 +141,6 @@ static int get_kernel_page_offset(struct kexec_info *info,
> }
>
> /**
> - * crash_exclude_range() - excludes memory region reserved for crashkernel
> - *
> - * Function locates where crashkernel reserved memory is and removes that region
> - * from the available memory regions.
> - */
> -static void crash_exclude_range(void)
> -{
> - const struct memory_range *range = &crash_kernel_mem;
> - int i;
> -
> - for (i = 0; i < usablemem_rgns.size; i++) {
> - struct memory_range *r = usablemem_rgns.ranges + i;
> -
> - /*
> - * We assume that crash area is fully contained in
> - * some larger memory area.
> - */
> - if (r->start <= range->start && r->end >= range->end) {
> - struct memory_range *new;
> - /*
> - * Let's split this area into 2 smaller ones and
> - * remove excluded range from between. First create
> - * new entry for the remaining area.
> - */
> - new = usablemem_rgns.ranges + usablemem_rgns.size;
> - new->start = range->end + 1;
> - new->end = r->end;
> - usablemem_rgns.size++;
> - /*
> - * Next update this area to end before excluded range.
> - */
> - r->end = range->start - 1;
> - break;
> - }
> - }
> -}
> -
> -/**
> * crash_get_memory_ranges() - read system physical memory
> *
> * Function reads through system physical memory and stores found memory regions
> @@ -181,16 +151,28 @@ static void crash_exclude_range(void)
> */
> static int crash_get_memory_ranges(void)
> {
> + int i;
> +
> if (usablemem_rgns.size < 1) {
> errno = EINVAL;
> return -1;
> }
>
> /*
> - * Exclude memory reserved for crashkernel (this may result a split memory
> - * region).
> + * Exclude all reserved memory from the usable memory regions.
> + * We want to avoid dumping the crashkernel region itself. Note
> + * that this may result memory regions in usablemem_rgns being
> + * split.
> */
> - crash_exclude_range();
> + for (i = 0; i < crash_reserved_rgns.size; i++) {
> + if (mem_regions_exclude(&usablemem_rgns,
> + &crash_reserved_rgns.ranges[i])) {
> + fprintf(stderr,
> + "Error: Number of crash memory ranges excedeed the max limit\n");
> + errno = ENOMEM;
> + return -1;
> + }
> + }
>
> /*
> * Make sure that the memory regions are sorted.
> @@ -388,6 +370,8 @@ static int iomem_range_callback(void *UNUSED(data), int UNUSED(nr),
> crash_kernel_mem.start = base;
> crash_kernel_mem.end = base + length - 1;
> crash_kernel_mem.type = RANGE_RAM;
> + return mem_regions_add(&crash_reserved_rgns,
> + base, length, RANGE_RAM);
> }
> else if (strncmp(str, SYSTEM_RAM, strlen(SYSTEM_RAM)) == 0) {
> return mem_regions_add(&usablemem_rgns,
> --
> 1.9.1
>
