[PATCH] sadump: Support more than 16TB physical memory space

[Atsushi Kumagai]

Hello HATAYAMA-san,

>This patch makes sadump format support more than 16TB physical memory
>space.

Thanks, I'll merge it into v1.5.8.

Atsushi Kumagai

>The limitation is caused by several members of dump_header structure:
>max_mapnr and the others. They have 4 byte length only. In particular,
>max_mapnr member gets overflow if more than 16TB physical memory space
>is given.
>
>To support more than 16TB physical memory space, this patch adds new 4
>64-bit length members in dump_header structure:
>
>- max_mapnr_64
>- total_ram_blocks_64
>- device_blocks_64
>- written_blocks_64
>
>Next table shows correspondence between the 32-bit version and the
>64-bit version members:
>
>    | 32-bit version         | 64-bit version            |
>    |------------------------+---------------------------|
>    | max_mapnr              | max_mapnr_64              |
>    | total_ram_blocks       | total_ram_blocks_64       |
>    | device_blocks          | device_blocks_64          |
>    | written_blocks         | written_blocks_64         |
>
>In addition, header_version member of dump_header structure is
>increased to 1 in this extended new format.
>
>Old makedumpfile can access the new sadump format under 16TB
>correctly.
>
>Current implementation treats vmcore with kernel version 2 or later as
>kernel version 1, assuming backward compatibility.
>
>Signed-off-by: HATAYAMA Daisuke <d.hatayama at jp.fujitsu.com>
>---
> sadump_info.c | 20 +++++++++++++++++---
> sadump_mod.h  |  8 ++++++++
> 2 files changed, 25 insertions(+), 3 deletions(-)
>
>diff --git a/sadump_info.c b/sadump_info.c
>index 9434ff7..e2c4f03 100644
>--- a/sadump_info.c
>+++ b/sadump_info.c
>@@ -84,6 +84,7 @@ struct sadump_info {
> 	unsigned long backup_src_size;
> 	unsigned long long backup_offset;
> 	int kdump_backed_up;
>+	mdf_pfn_t max_mapnr;
> };
>
> static char *guid_to_str(efi_guid_t *guid, char *buf, size_t buflen);
>@@ -625,6 +626,19 @@ restart:
> 		offset += sh->sub_hdr_size * block_size;
> 	}
>
>+	switch (sh->header_version) {
>+	case 0:
>+		si->max_mapnr = (mdf_pfn_t)(uint64_t)sh->max_mapnr;
>+		break;
>+	default:
>+		ERRMSG("sadump: unsupported header version: %u\n"
>+		       "sadump: assuming header version: 1\n",
>+		       sh->header_version);
>+	case 1:
>+		si->max_mapnr = (mdf_pfn_t)sh->max_mapnr_64;
>+		break;
>+	}
>+
> 	if (!sh->bitmap_blocks) {
> 		DEBUG_MSG("sadump: bitmap_blocks is zero\n");
> 		return FALSE;
>@@ -775,7 +789,7 @@ sadump_initialize_bitmap_memory(void)
> 	memset(bmp->buf, 0, BUFSIZE_BITMAP);
> 	bmp->offset = dumpable_bitmap_offset;
>
>-	max_section = divideup(sh->max_mapnr, SADUMP_PF_SECTION_NUM);
>+	max_section = divideup(si->max_mapnr, SADUMP_PF_SECTION_NUM);
>
> 	block_table = calloc(sizeof(unsigned long long), max_section);
> 	if (block_table == NULL) {
>@@ -906,7 +920,7 @@ sadump_set_timestamp(struct timeval *ts)
> mdf_pfn_t
> sadump_get_max_mapnr(void)
> {
>-	return si->sh_memory->max_mapnr;
>+	return si->max_mapnr;
> }
>
> #ifdef __x86_64__
>@@ -964,7 +978,7 @@ readpage_sadump(unsigned long long paddr, void *bufptr)
>
> 	pfn = paddr_to_pfn(paddr);
>
>-	if (pfn >= si->sh_memory->max_mapnr)
>+	if (pfn >= si->max_mapnr)
> 		return FALSE;
>
> 	if (!is_dumpable(info->bitmap_memory, pfn)) {
>diff --git a/sadump_mod.h b/sadump_mod.h
>index afeead8..0dd5bb5 100644
>--- a/sadump_mod.h
>+++ b/sadump_mod.h
>@@ -106,6 +106,14 @@ struct sadump_header {
> 	uint32_t written_blocks;	/* Number of written blocks */
> 	uint32_t current_cpu;	/* CPU# which handles dump */
> 	uint32_t nr_cpus;	/* Number of CPUs */
>+	/*
>+	 * The members from below are supported in header version 1
>+	 * and later.
>+	 */
>+	uint64_t max_mapnr_64;
>+	uint64_t total_ram_blocks_64;
>+	uint64_t device_blocks_64;
>+	uint64_t written_blocks_64;
> };
>
> struct sadump_apic_state {
>--
>1.9.3
>