blob: 309af6c6012cc9972e2d7975cc2e17657001fc49 [file] [log] [blame]
/* Copyright (c) 2017-2018, The Linux Foundation. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 and
* only version 2 as published by the Free Software Foundation.
*
* 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.
*/
#define pr_fmt(fmt) "Minidump: " fmt
#include <linux/init.h>
#include <linux/export.h>
#include <linux/kernel.h>
#include <linux/err.h>
#include <linux/elf.h>
#include <linux/errno.h>
#include <linux/string.h>
#include <linux/slab.h>
#include <soc/qcom/smem.h>
#include <soc/qcom/minidump.h>
#include "minidump_private.h"
#define MAX_NUM_ENTRIES (CONFIG_MINIDUMP_MAX_ENTRIES + 1)
#define MAX_STRTBL_SIZE (MAX_NUM_ENTRIES * MAX_REGION_NAME_LENGTH)
/**
* md_table : Local Minidump toc holder
* @num_regions : Number of regions requested
* @md_ss_toc : HLOS toc pointer
* @md_gbl_toc : Global toc pointer
* @md_regions : HLOS regions base pointer
* @entry : array of HLOS regions requested
*/
struct md_table {
u32 revision;
u32 num_regions;
struct md_ss_toc *md_ss_toc;
struct md_global_toc *md_gbl_toc;
struct md_ss_region *md_regions;
struct md_region entry[MAX_NUM_ENTRIES];
};
/**
* md_elfhdr: Minidump table elf header
* @ehdr: elf main header
* @shdr: Section header
* @phdr: Program header
* @elf_offset: section offset in elf
* @strtable_idx: string table current index position
*/
struct md_elfhdr {
struct elfhdr *ehdr;
struct elf_shdr *shdr;
struct elf_phdr *phdr;
u64 elf_offset;
u64 strtable_idx;
};
/* Protect elfheader and smem table from deferred calls contention */
static DEFINE_SPINLOCK(mdt_lock);
static struct md_table minidump_table;
static struct md_elfhdr minidump_elfheader;
/* Number of pending entries to be added in ToC regions */
static unsigned int pendings;
static inline char *elf_lookup_string(struct elfhdr *hdr, int offset)
{
char *strtab = elf_str_table(hdr);
if ((strtab == NULL) || (minidump_elfheader.strtable_idx < offset))
return NULL;
return strtab + offset;
}
static inline unsigned int set_section_name(const char *name)
{
char *strtab = elf_str_table(minidump_elfheader.ehdr);
int idx = minidump_elfheader.strtable_idx;
int ret = 0;
if ((strtab == NULL) || (name == NULL))
return 0;
ret = idx;
idx += strlcpy((strtab + idx), name, MAX_REGION_NAME_LENGTH);
minidump_elfheader.strtable_idx = idx + 1;
return ret;
}
static inline bool md_check_name(const char *name)
{
struct md_region *mde = minidump_table.entry;
int i, regno = minidump_table.num_regions;
for (i = 0; i < regno; i++, mde++)
if (!strcmp(mde->name, name))
return true;
return false;
}
/* Return next seq no, if name already exists in the table */
static inline int md_get_seq_num(const char *name)
{
struct md_ss_region *mde = minidump_table.md_regions;
int i, regno = minidump_table.md_ss_toc->ss_region_count;
int seqno = 0;
for (i = 0; i < (regno - 1); i++, mde++) {
if (!strcmp(mde->name, name)) {
if (mde->seq_num >= seqno)
seqno = mde->seq_num + 1;
}
}
return seqno;
}
/* Update Mini dump table in SMEM */
static void md_update_ss_toc(const struct md_region *entry)
{
struct md_ss_region *mdr;
struct elfhdr *hdr = minidump_elfheader.ehdr;
struct elf_shdr *shdr = elf_section(hdr, hdr->e_shnum++);
struct elf_phdr *phdr = elf_program(hdr, hdr->e_phnum++);
int reg_cnt = minidump_table.md_ss_toc->ss_region_count++;
mdr = &minidump_table.md_regions[reg_cnt];
strlcpy(mdr->name, entry->name, sizeof(mdr->name));
mdr->region_base_address = entry->phys_addr;
mdr->region_size = entry->size;
mdr->seq_num = md_get_seq_num(entry->name);
/* Update elf header */
shdr->sh_type = SHT_PROGBITS;
shdr->sh_name = set_section_name(mdr->name);
shdr->sh_addr = (elf_addr_t)entry->virt_addr;
shdr->sh_size = mdr->region_size;
shdr->sh_flags = SHF_WRITE;
shdr->sh_offset = minidump_elfheader.elf_offset;
shdr->sh_entsize = 0;
phdr->p_type = PT_LOAD;
phdr->p_offset = minidump_elfheader.elf_offset;
phdr->p_vaddr = entry->virt_addr;
phdr->p_paddr = entry->phys_addr;
phdr->p_filesz = phdr->p_memsz = mdr->region_size;
phdr->p_flags = PF_R | PF_W;
minidump_elfheader.elf_offset += shdr->sh_size;
mdr->md_valid = MD_REGION_VALID;
}
bool msm_minidump_enabled(void)
{
bool ret = false;
spin_lock(&mdt_lock);
if (minidump_table.md_ss_toc &&
(minidump_table.md_ss_toc->md_ss_enable_status ==
MD_SS_ENABLED))
ret = true;
spin_unlock(&mdt_lock);
return ret;
}
EXPORT_SYMBOL(msm_minidump_enabled);
static inline int validate_region(const struct md_region *entry)
{
if (!entry || (strlen(entry->name) > MAX_NAME_LENGTH) ||
!entry->virt_addr) {
pr_err("Invalid entry details\n");
return -EINVAL;
}
if (!IS_ALIGNED(entry->size, 4)) {
pr_err("size should be 4 byte aligned\n");
return -EINVAL;
}
return 0;
}
int msm_minidump_update_region(int regno, const struct md_region *entry)
{
struct md_region *mdr;
struct md_ss_region *mdssr;
struct elfhdr *hdr = minidump_elfheader.ehdr;
struct elf_shdr *shdr;
struct elf_phdr *phdr;
if (validate_region(entry) || (regno >= MAX_NUM_ENTRIES))
return -EINVAL;
if (!md_check_name(entry->name)) {
pr_err("Region:[%s] does not exist to update.\n", entry->name);
return -ENOMEM;
}
mdr = &minidump_table.entry[regno];
mdr->virt_addr = entry->virt_addr;
mdr->phys_addr = entry->phys_addr;
mdssr = &minidump_table.md_regions[regno + 1];
mdssr->region_base_address = entry->phys_addr;
shdr = elf_section(hdr, regno + 4);
phdr = elf_program(hdr, regno + 1);
shdr->sh_addr = (elf_addr_t)entry->virt_addr;
phdr->p_vaddr = entry->virt_addr;
phdr->p_paddr = entry->phys_addr;
return 0;
}
EXPORT_SYMBOL(msm_minidump_update_region);
int msm_minidump_add_region(const struct md_region *entry)
{
u32 entries;
struct md_region *mdr;
if (validate_region(entry))
return -EINVAL;
if (md_check_name(entry->name)) {
pr_err("Region name [%s] already registered\n", entry->name);
return -EEXIST;
}
spin_lock(&mdt_lock);
entries = minidump_table.num_regions;
if (entries >= MAX_NUM_ENTRIES) {
pr_err("Maximum entries reached.\n");
spin_unlock(&mdt_lock);
return -ENOMEM;
}
mdr = &minidump_table.entry[entries];
strlcpy(mdr->name, entry->name, sizeof(mdr->name));
mdr->virt_addr = entry->virt_addr;
mdr->phys_addr = entry->phys_addr;
mdr->size = entry->size;
mdr->id = entry->id;
minidump_table.num_regions = entries + 1;
if (minidump_table.md_ss_toc &&
(minidump_table.md_ss_toc->md_ss_enable_status ==
MD_SS_ENABLED))
md_update_ss_toc(entry);
else
pendings++;
spin_unlock(&mdt_lock);
return entries;
}
EXPORT_SYMBOL(msm_minidump_add_region);
static int msm_minidump_add_header(void)
{
struct md_ss_region *mdreg = &minidump_table.md_regions[0];
struct elfhdr *ehdr;
struct elf_shdr *shdr;
struct elf_phdr *phdr;
unsigned int strtbl_off, elfh_size, phdr_off;
char *banner;
/* Header buffer contains:
* elf header, MAX_NUM_ENTRIES+4 of section and program elf headers,
* string table section and linux banner.
*/
elfh_size = sizeof(*ehdr) + MAX_STRTBL_SIZE + (strlen(linux_banner) +
1) + ((sizeof(*shdr) + sizeof(*phdr)) * (MAX_NUM_ENTRIES + 4));
elfh_size = ALIGN(elfh_size, 4);
minidump_elfheader.ehdr = kzalloc(elfh_size, GFP_KERNEL);
if (!minidump_elfheader.ehdr)
return -ENOMEM;
strlcpy(mdreg->name, "KELF_HEADER", sizeof(mdreg->name));
mdreg->region_base_address = virt_to_phys(minidump_elfheader.ehdr);
mdreg->region_size = elfh_size;
ehdr = minidump_elfheader.ehdr;
/* Assign section/program headers offset */
minidump_elfheader.shdr = shdr = (struct elf_shdr *)(ehdr + 1);
minidump_elfheader.phdr = phdr =
(struct elf_phdr *)(shdr + MAX_NUM_ENTRIES);
phdr_off = sizeof(*ehdr) + (sizeof(*shdr) * MAX_NUM_ENTRIES);
memcpy(ehdr->e_ident, ELFMAG, SELFMAG);
ehdr->e_ident[EI_CLASS] = ELF_CLASS;
ehdr->e_ident[EI_DATA] = ELF_DATA;
ehdr->e_ident[EI_VERSION] = EV_CURRENT;
ehdr->e_ident[EI_OSABI] = ELF_OSABI;
ehdr->e_type = ET_CORE;
ehdr->e_machine = ELF_ARCH;
ehdr->e_version = EV_CURRENT;
ehdr->e_ehsize = sizeof(*ehdr);
ehdr->e_phoff = phdr_off;
ehdr->e_phentsize = sizeof(*phdr);
ehdr->e_shoff = sizeof(*ehdr);
ehdr->e_shentsize = sizeof(*shdr);
ehdr->e_shstrndx = 1;
minidump_elfheader.elf_offset = elfh_size;
/*
* First section header should be NULL,
* 2nd section is string table.
*/
minidump_elfheader.strtable_idx = 1;
strtbl_off = sizeof(*ehdr) +
((sizeof(*phdr) + sizeof(*shdr)) * MAX_NUM_ENTRIES);
shdr++;
shdr->sh_type = SHT_STRTAB;
shdr->sh_offset = (elf_addr_t)strtbl_off;
shdr->sh_size = MAX_STRTBL_SIZE;
shdr->sh_entsize = 0;
shdr->sh_flags = 0;
shdr->sh_name = set_section_name("STR_TBL");
shdr++;
/* 3rd section is for minidump_table VA, used by parsers */
shdr->sh_type = SHT_PROGBITS;
shdr->sh_entsize = 0;
shdr->sh_flags = 0;
shdr->sh_addr = (elf_addr_t)&minidump_table;
shdr->sh_name = set_section_name("minidump_table");
shdr++;
/* 4th section is linux banner */
banner = (char *)ehdr + strtbl_off + MAX_STRTBL_SIZE;
strlcpy(banner, linux_banner, strlen(linux_banner) + 1);
shdr->sh_type = SHT_PROGBITS;
shdr->sh_offset = (elf_addr_t)(strtbl_off + MAX_STRTBL_SIZE);
shdr->sh_size = strlen(linux_banner) + 1;
shdr->sh_addr = (elf_addr_t)linux_banner;
shdr->sh_entsize = 0;
shdr->sh_flags = SHF_WRITE;
shdr->sh_name = set_section_name("linux_banner");
phdr->p_type = PT_LOAD;
phdr->p_offset = (elf_addr_t)(strtbl_off + MAX_STRTBL_SIZE);
phdr->p_vaddr = (elf_addr_t)linux_banner;
phdr->p_paddr = virt_to_phys(linux_banner);
phdr->p_filesz = phdr->p_memsz = strlen(linux_banner) + 1;
phdr->p_flags = PF_R | PF_W;
/* Update headers count*/
ehdr->e_phnum = 1;
ehdr->e_shnum = 4;
mdreg->md_valid = MD_REGION_VALID;
return 0;
}
static int __init msm_minidump_init(void)
{
unsigned int i, size;
struct md_region *mdr;
struct md_global_toc *md_global_toc;
struct md_ss_toc *md_ss_toc;
/* Get Minidump table */
md_global_toc = smem_get_entry(SBL_MINIDUMP_SMEM_ID, &size, 0,
SMEM_ANY_HOST_FLAG);
if (IS_ERR_OR_NULL(md_global_toc)) {
pr_err("SMEM is not initialized.\n");
return -ENODEV;
}
/*Check global minidump support initialization */
if (!md_global_toc->md_toc_init) {
pr_err("System Minidump TOC not initialized\n");
return -ENODEV;
}
minidump_table.md_gbl_toc = md_global_toc;
minidump_table.revision = md_global_toc->md_revision;
md_ss_toc = &md_global_toc->md_ss_toc[MD_SS_HLOS_ID];
md_ss_toc->encryption_status = MD_SS_ENCR_NONE;
md_ss_toc->encryption_required = MD_SS_ENCR_REQ;
minidump_table.md_ss_toc = md_ss_toc;
minidump_table.md_regions = kzalloc((MAX_NUM_ENTRIES *
sizeof(struct md_ss_region)), GFP_KERNEL);
if (!minidump_table.md_regions)
return -ENOMEM;
md_ss_toc->md_ss_smem_regions_baseptr =
virt_to_phys(minidump_table.md_regions);
/* First entry would be ELF header */
md_ss_toc->ss_region_count = 1;
msm_minidump_add_header();
/* Add pending entries to HLOS TOC */
spin_lock(&mdt_lock);
md_ss_toc->md_ss_toc_init = 1;
md_ss_toc->md_ss_enable_status = MD_SS_ENABLED;
for (i = 0; i < pendings; i++) {
mdr = &minidump_table.entry[i];
md_update_ss_toc(mdr);
}
pendings = 0;
spin_unlock(&mdt_lock);
pr_info("Enabled with max number of regions %d\n",
CONFIG_MINIDUMP_MAX_ENTRIES);
return 0;
}
subsys_initcall(msm_minidump_init)