linux/arch/powerpc/include/asm/fadump.h
Mahesh Salgaonkar 2df173d9e8 fadump: Initialize elfcore header and add PT_LOAD program headers.
Build the crash memory range list by traversing through system memory during
the first kernel before we register for firmware-assisted dump. After the
successful dump registration, initialize the elfcore header and populate
PT_LOAD program headers with crash memory ranges. The elfcore header is
saved in the scratch area within the reserved memory. The scratch area starts
at the end of the memory reserved for saving RMR region contents. The
scratch area contains fadump crash info structure that contains magic number
for fadump validation and physical address where the eflcore header can be
found. This structure will also be used to pass some important crash info
data to the second kernel which will help second kernel to populate ELF core
header with correct data before it gets exported through /proc/vmcore. Since
the firmware preserves the entire partition memory at the time of crash the
contents of the scratch area will be preserved till second kernel boot.

Since the memory dump exported through /proc/vmcore is in ELF format similar
to kdump, it will help us to reuse the kdump infrastructure for dump capture
and filtering. Unlike phyp dump, userspace tool does not need to refer any
sysfs interface while reading /proc/vmcore.

NOTE: The current design implementation does not address a possibility of
introducing additional fields (in future) to this structure without affecting
compatibility. It's on TODO list to come up with better approach to
address this.

Reserved dump area start => +-------------------------------------+
                            |  CPU state dump data                |
                            +-------------------------------------+
                            |  HPTE region data                   |
                            +-------------------------------------+
                            |  RMR region data                    |
Scratch area start       => +-------------------------------------+
                            |  fadump crash info structure {      |
                            |     magic nummber                   |
                     +------|---- elfcorehdr_addr                 |
                     |      |  }                                  |
                     +----> +-------------------------------------+
                            |  ELF core header                    |
Reserved dump area end   => +-------------------------------------+

Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-02-23 10:50:01 +11:00

172 lines
4.7 KiB
C

/*
* Firmware Assisted dump header file.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
* Copyright 2011 IBM Corporation
* Author: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
*/
#ifndef __PPC64_FA_DUMP_H__
#define __PPC64_FA_DUMP_H__
#ifdef CONFIG_FA_DUMP
/*
* The RMA region will be saved for later dumping when kernel crashes.
* RMA is Real Mode Area, the first block of logical memory address owned
* by logical partition, containing the storage that may be accessed with
* translate off.
*/
#define RMA_START 0x0
#define RMA_END (ppc64_rma_size)
/*
* On some Power systems where RMO is 128MB, it still requires minimum of
* 256MB for kernel to boot successfully. When kdump infrastructure is
* configured to save vmcore over network, we run into OOM issue while
* loading modules related to network setup. Hence we need aditional 64M
* of memory to avoid OOM issue.
*/
#define MIN_BOOT_MEM (((RMA_END < (0x1UL << 28)) ? (0x1UL << 28) : RMA_END) \
+ (0x1UL << 26))
#define memblock_num_regions(memblock_type) (memblock.memblock_type.cnt)
#ifndef ELF_CORE_EFLAGS
#define ELF_CORE_EFLAGS 0
#endif
/* Firmware provided dump sections */
#define FADUMP_CPU_STATE_DATA 0x0001
#define FADUMP_HPTE_REGION 0x0002
#define FADUMP_REAL_MODE_REGION 0x0011
/* Dump request flag */
#define FADUMP_REQUEST_FLAG 0x00000001
/* FAD commands */
#define FADUMP_REGISTER 1
#define FADUMP_UNREGISTER 2
#define FADUMP_INVALIDATE 3
/* Dump status flag */
#define FADUMP_ERROR_FLAG 0x2000
/* Kernel Dump section info */
struct fadump_section {
u32 request_flag;
u16 source_data_type;
u16 error_flags;
u64 source_address;
u64 source_len;
u64 bytes_dumped;
u64 destination_address;
};
/* ibm,configure-kernel-dump header. */
struct fadump_section_header {
u32 dump_format_version;
u16 dump_num_sections;
u16 dump_status_flag;
u32 offset_first_dump_section;
/* Fields for disk dump option. */
u32 dd_block_size;
u64 dd_block_offset;
u64 dd_num_blocks;
u32 dd_offset_disk_path;
/* Maximum time allowed to prevent an automatic dump-reboot. */
u32 max_time_auto;
};
/*
* Firmware Assisted dump memory structure. This structure is required for
* registering future kernel dump with power firmware through rtas call.
*
* No disk dump option. Hence disk dump path string section is not included.
*/
struct fadump_mem_struct {
struct fadump_section_header header;
/* Kernel dump sections */
struct fadump_section cpu_state_data;
struct fadump_section hpte_region;
struct fadump_section rmr_region;
};
/* Firmware-assisted dump configuration details. */
struct fw_dump {
unsigned long cpu_state_data_size;
unsigned long hpte_region_size;
unsigned long boot_memory_size;
unsigned long reserve_dump_area_start;
unsigned long reserve_dump_area_size;
/* cmd line option during boot */
unsigned long reserve_bootvar;
unsigned long fadumphdr_addr;
int ibm_configure_kernel_dump;
unsigned long fadump_enabled:1;
unsigned long fadump_supported:1;
unsigned long dump_active:1;
unsigned long dump_registered:1;
};
/*
* Copy the ascii values for first 8 characters from a string into u64
* variable at their respective indexes.
* e.g.
* The string "FADMPINF" will be converted into 0x4641444d50494e46
*/
static inline u64 str_to_u64(const char *str)
{
u64 val = 0;
int i;
for (i = 0; i < sizeof(val); i++)
val = (*str) ? (val << 8) | *str++ : val << 8;
return val;
}
#define STR_TO_HEX(x) str_to_u64(x)
#define FADUMP_CRASH_INFO_MAGIC STR_TO_HEX("FADMPINF")
/* fadump crash info structure */
struct fadump_crash_info_header {
u64 magic_number;
u64 elfcorehdr_addr;
};
/* Crash memory ranges */
#define INIT_CRASHMEM_RANGES (INIT_MEMBLOCK_REGIONS + 2)
struct fad_crash_memory_ranges {
unsigned long long base;
unsigned long long size;
};
extern int early_init_dt_scan_fw_dump(unsigned long node,
const char *uname, int depth, void *data);
extern int fadump_reserve_mem(void);
extern int setup_fadump(void);
extern int is_fadump_active(void);
#else /* CONFIG_FA_DUMP */
static inline int is_fadump_active(void) { return 0; }
#endif
#endif