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1706 lines
42 KiB
1706 lines
42 KiB
// SPDX-License-Identifier: GPL-2.0-or-later |
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/* |
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* Firmware Assisted dump: A robust mechanism to get reliable kernel crash |
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* dump with assistance from firmware. This approach does not use kexec, |
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* instead firmware assists in booting the kdump kernel while preserving |
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* memory contents. The most of the code implementation has been adapted |
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* from phyp assisted dump implementation written by Linas Vepstas and |
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* Manish Ahuja |
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* |
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* Copyright 2011 IBM Corporation |
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* Author: Mahesh Salgaonkar <[email protected]> |
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*/ |
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|
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#undef DEBUG |
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#define pr_fmt(fmt) "fadump: " fmt |
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|
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#include <linux/string.h> |
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#include <linux/memblock.h> |
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#include <linux/delay.h> |
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#include <linux/seq_file.h> |
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#include <linux/crash_dump.h> |
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#include <linux/kobject.h> |
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#include <linux/sysfs.h> |
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#include <linux/slab.h> |
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#include <linux/cma.h> |
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#include <linux/hugetlb.h> |
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|
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#include <asm/debugfs.h> |
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#include <asm/page.h> |
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#include <asm/prom.h> |
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#include <asm/fadump.h> |
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#include <asm/fadump-internal.h> |
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#include <asm/setup.h> |
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|
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/* |
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* The CPU who acquired the lock to trigger the fadump crash should |
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* wait for other CPUs to enter. |
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* |
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* The timeout is in milliseconds. |
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*/ |
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#define CRASH_TIMEOUT 500 |
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|
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static struct fw_dump fw_dump; |
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|
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static void __init fadump_reserve_crash_area(u64 base); |
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|
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struct kobject *fadump_kobj; |
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|
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#ifndef CONFIG_PRESERVE_FA_DUMP |
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|
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static atomic_t cpus_in_fadump; |
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static DEFINE_MUTEX(fadump_mutex); |
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|
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struct fadump_mrange_info crash_mrange_info = { "crash", NULL, 0, 0, 0, false }; |
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|
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#define RESERVED_RNGS_SZ 16384 /* 16K - 128 entries */ |
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#define RESERVED_RNGS_CNT (RESERVED_RNGS_SZ / \ |
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sizeof(struct fadump_memory_range)) |
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static struct fadump_memory_range rngs[RESERVED_RNGS_CNT]; |
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struct fadump_mrange_info reserved_mrange_info = { "reserved", rngs, |
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RESERVED_RNGS_SZ, 0, |
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RESERVED_RNGS_CNT, true }; |
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|
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static void __init early_init_dt_scan_reserved_ranges(unsigned long node); |
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|
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#ifdef CONFIG_CMA |
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static struct cma *fadump_cma; |
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|
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/* |
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* fadump_cma_init() - Initialize CMA area from a fadump reserved memory |
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* |
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* This function initializes CMA area from fadump reserved memory. |
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* The total size of fadump reserved memory covers for boot memory size |
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* + cpu data size + hpte size and metadata. |
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* Initialize only the area equivalent to boot memory size for CMA use. |
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* The reamining portion of fadump reserved memory will be not given |
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* to CMA and pages for thoes will stay reserved. boot memory size is |
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* aligned per CMA requirement to satisy cma_init_reserved_mem() call. |
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* But for some reason even if it fails we still have the memory reservation |
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* with us and we can still continue doing fadump. |
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*/ |
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int __init fadump_cma_init(void) |
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{ |
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unsigned long long base, size; |
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int rc; |
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|
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if (!fw_dump.fadump_enabled) |
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return 0; |
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|
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/* |
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* Do not use CMA if user has provided fadump=nocma kernel parameter. |
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* Return 1 to continue with fadump old behaviour. |
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*/ |
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if (fw_dump.nocma) |
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return 1; |
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|
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base = fw_dump.reserve_dump_area_start; |
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size = fw_dump.boot_memory_size; |
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|
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if (!size) |
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return 0; |
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|
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rc = cma_init_reserved_mem(base, size, 0, "fadump_cma", &fadump_cma); |
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if (rc) { |
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pr_err("Failed to init cma area for firmware-assisted dump,%d\n", rc); |
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/* |
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* Though the CMA init has failed we still have memory |
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* reservation with us. The reserved memory will be |
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* blocked from production system usage. Hence return 1, |
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* so that we can continue with fadump. |
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*/ |
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return 1; |
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} |
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|
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/* |
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* So we now have successfully initialized cma area for fadump. |
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*/ |
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pr_info("Initialized 0x%lx bytes cma area at %ldMB from 0x%lx " |
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"bytes of memory reserved for firmware-assisted dump\n", |
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cma_get_size(fadump_cma), |
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(unsigned long)cma_get_base(fadump_cma) >> 20, |
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fw_dump.reserve_dump_area_size); |
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return 1; |
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} |
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#else |
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static int __init fadump_cma_init(void) { return 1; } |
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#endif /* CONFIG_CMA */ |
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|
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/* Scan the Firmware Assisted dump configuration details. */ |
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int __init early_init_dt_scan_fw_dump(unsigned long node, const char *uname, |
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int depth, void *data) |
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{ |
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if (depth == 0) { |
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early_init_dt_scan_reserved_ranges(node); |
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return 0; |
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} |
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|
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if (depth != 1) |
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return 0; |
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|
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if (strcmp(uname, "rtas") == 0) { |
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rtas_fadump_dt_scan(&fw_dump, node); |
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return 1; |
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} |
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|
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if (strcmp(uname, "ibm,opal") == 0) { |
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opal_fadump_dt_scan(&fw_dump, node); |
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return 1; |
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} |
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|
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return 0; |
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} |
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|
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/* |
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* If fadump is registered, check if the memory provided |
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* falls within boot memory area and reserved memory area. |
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*/ |
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int is_fadump_memory_area(u64 addr, unsigned long size) |
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{ |
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u64 d_start, d_end; |
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|
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if (!fw_dump.dump_registered) |
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return 0; |
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|
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if (!size) |
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return 0; |
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|
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d_start = fw_dump.reserve_dump_area_start; |
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d_end = d_start + fw_dump.reserve_dump_area_size; |
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if (((addr + size) > d_start) && (addr <= d_end)) |
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return 1; |
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|
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return (addr <= fw_dump.boot_mem_top); |
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} |
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|
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int should_fadump_crash(void) |
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{ |
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if (!fw_dump.dump_registered || !fw_dump.fadumphdr_addr) |
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return 0; |
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return 1; |
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} |
|
|
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int is_fadump_active(void) |
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{ |
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return fw_dump.dump_active; |
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} |
|
|
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/* |
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* Returns true, if there are no holes in memory area between d_start to d_end, |
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* false otherwise. |
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*/ |
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static bool is_fadump_mem_area_contiguous(u64 d_start, u64 d_end) |
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{ |
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phys_addr_t reg_start, reg_end; |
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bool ret = false; |
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u64 i, start, end; |
|
|
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for_each_mem_range(i, ®_start, ®_end) { |
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start = max_t(u64, d_start, reg_start); |
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end = min_t(u64, d_end, reg_end); |
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if (d_start < end) { |
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/* Memory hole from d_start to start */ |
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if (start > d_start) |
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break; |
|
|
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if (end == d_end) { |
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ret = true; |
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break; |
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} |
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|
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d_start = end + 1; |
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} |
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} |
|
|
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return ret; |
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} |
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|
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/* |
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* Returns true, if there are no holes in boot memory area, |
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* false otherwise. |
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*/ |
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bool is_fadump_boot_mem_contiguous(void) |
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{ |
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unsigned long d_start, d_end; |
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bool ret = false; |
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int i; |
|
|
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for (i = 0; i < fw_dump.boot_mem_regs_cnt; i++) { |
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d_start = fw_dump.boot_mem_addr[i]; |
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d_end = d_start + fw_dump.boot_mem_sz[i]; |
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|
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ret = is_fadump_mem_area_contiguous(d_start, d_end); |
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if (!ret) |
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break; |
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} |
|
|
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return ret; |
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} |
|
|
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/* |
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* Returns true, if there are no holes in reserved memory area, |
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* false otherwise. |
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*/ |
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bool is_fadump_reserved_mem_contiguous(void) |
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{ |
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u64 d_start, d_end; |
|
|
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d_start = fw_dump.reserve_dump_area_start; |
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d_end = d_start + fw_dump.reserve_dump_area_size; |
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return is_fadump_mem_area_contiguous(d_start, d_end); |
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} |
|
|
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/* Print firmware assisted dump configurations for debugging purpose. */ |
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static void fadump_show_config(void) |
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{ |
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int i; |
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|
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pr_debug("Support for firmware-assisted dump (fadump): %s\n", |
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(fw_dump.fadump_supported ? "present" : "no support")); |
|
|
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if (!fw_dump.fadump_supported) |
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return; |
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|
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pr_debug("Fadump enabled : %s\n", |
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(fw_dump.fadump_enabled ? "yes" : "no")); |
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pr_debug("Dump Active : %s\n", |
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(fw_dump.dump_active ? "yes" : "no")); |
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pr_debug("Dump section sizes:\n"); |
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pr_debug(" CPU state data size: %lx\n", fw_dump.cpu_state_data_size); |
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pr_debug(" HPTE region size : %lx\n", fw_dump.hpte_region_size); |
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pr_debug(" Boot memory size : %lx\n", fw_dump.boot_memory_size); |
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pr_debug(" Boot memory top : %llx\n", fw_dump.boot_mem_top); |
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pr_debug("Boot memory regions cnt: %llx\n", fw_dump.boot_mem_regs_cnt); |
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for (i = 0; i < fw_dump.boot_mem_regs_cnt; i++) { |
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pr_debug("[%03d] base = %llx, size = %llx\n", i, |
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fw_dump.boot_mem_addr[i], fw_dump.boot_mem_sz[i]); |
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} |
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} |
|
|
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/** |
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* fadump_calculate_reserve_size(): reserve variable boot area 5% of System RAM |
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* |
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* Function to find the largest memory size we need to reserve during early |
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* boot process. This will be the size of the memory that is required for a |
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* kernel to boot successfully. |
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* |
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* This function has been taken from phyp-assisted dump feature implementation. |
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* |
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* returns larger of 256MB or 5% rounded down to multiples of 256MB. |
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* |
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* TODO: Come up with better approach to find out more accurate memory size |
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* that is required for a kernel to boot successfully. |
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* |
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*/ |
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static __init u64 fadump_calculate_reserve_size(void) |
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{ |
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u64 base, size, bootmem_min; |
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int ret; |
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|
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if (fw_dump.reserve_bootvar) |
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pr_warn("'fadump_reserve_mem=' parameter is deprecated in favor of 'crashkernel=' parameter.\n"); |
|
|
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/* |
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* Check if the size is specified through crashkernel= cmdline |
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* option. If yes, then use that but ignore base as fadump reserves |
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* memory at a predefined offset. |
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*/ |
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ret = parse_crashkernel(boot_command_line, memblock_phys_mem_size(), |
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&size, &base); |
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if (ret == 0 && size > 0) { |
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unsigned long max_size; |
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|
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if (fw_dump.reserve_bootvar) |
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pr_info("Using 'crashkernel=' parameter for memory reservation.\n"); |
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|
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fw_dump.reserve_bootvar = (unsigned long)size; |
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|
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/* |
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* Adjust if the boot memory size specified is above |
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* the upper limit. |
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*/ |
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max_size = memblock_phys_mem_size() / MAX_BOOT_MEM_RATIO; |
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if (fw_dump.reserve_bootvar > max_size) { |
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fw_dump.reserve_bootvar = max_size; |
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pr_info("Adjusted boot memory size to %luMB\n", |
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(fw_dump.reserve_bootvar >> 20)); |
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} |
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|
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return fw_dump.reserve_bootvar; |
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} else if (fw_dump.reserve_bootvar) { |
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/* |
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* 'fadump_reserve_mem=' is being used to reserve memory |
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* for firmware-assisted dump. |
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*/ |
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return fw_dump.reserve_bootvar; |
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} |
|
|
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/* divide by 20 to get 5% of value */ |
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size = memblock_phys_mem_size() / 20; |
|
|
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/* round it down in multiples of 256 */ |
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size = size & ~0x0FFFFFFFUL; |
|
|
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/* Truncate to memory_limit. We don't want to over reserve the memory.*/ |
|
if (memory_limit && size > memory_limit) |
|
size = memory_limit; |
|
|
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bootmem_min = fw_dump.ops->fadump_get_bootmem_min(); |
|
return (size > bootmem_min ? size : bootmem_min); |
|
} |
|
|
|
/* |
|
* Calculate the total memory size required to be reserved for |
|
* firmware-assisted dump registration. |
|
*/ |
|
static unsigned long get_fadump_area_size(void) |
|
{ |
|
unsigned long size = 0; |
|
|
|
size += fw_dump.cpu_state_data_size; |
|
size += fw_dump.hpte_region_size; |
|
size += fw_dump.boot_memory_size; |
|
size += sizeof(struct fadump_crash_info_header); |
|
size += sizeof(struct elfhdr); /* ELF core header.*/ |
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size += sizeof(struct elf_phdr); /* place holder for cpu notes */ |
|
/* Program headers for crash memory regions. */ |
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size += sizeof(struct elf_phdr) * (memblock_num_regions(memory) + 2); |
|
|
|
size = PAGE_ALIGN(size); |
|
|
|
/* This is to hold kernel metadata on platforms that support it */ |
|
size += (fw_dump.ops->fadump_get_metadata_size ? |
|
fw_dump.ops->fadump_get_metadata_size() : 0); |
|
return size; |
|
} |
|
|
|
static int __init add_boot_mem_region(unsigned long rstart, |
|
unsigned long rsize) |
|
{ |
|
int i = fw_dump.boot_mem_regs_cnt++; |
|
|
|
if (fw_dump.boot_mem_regs_cnt > FADUMP_MAX_MEM_REGS) { |
|
fw_dump.boot_mem_regs_cnt = FADUMP_MAX_MEM_REGS; |
|
return 0; |
|
} |
|
|
|
pr_debug("Added boot memory range[%d] [%#016lx-%#016lx)\n", |
|
i, rstart, (rstart + rsize)); |
|
fw_dump.boot_mem_addr[i] = rstart; |
|
fw_dump.boot_mem_sz[i] = rsize; |
|
return 1; |
|
} |
|
|
|
/* |
|
* Firmware usually has a hard limit on the data it can copy per region. |
|
* Honour that by splitting a memory range into multiple regions. |
|
*/ |
|
static int __init add_boot_mem_regions(unsigned long mstart, |
|
unsigned long msize) |
|
{ |
|
unsigned long rstart, rsize, max_size; |
|
int ret = 1; |
|
|
|
rstart = mstart; |
|
max_size = fw_dump.max_copy_size ? fw_dump.max_copy_size : msize; |
|
while (msize) { |
|
if (msize > max_size) |
|
rsize = max_size; |
|
else |
|
rsize = msize; |
|
|
|
ret = add_boot_mem_region(rstart, rsize); |
|
if (!ret) |
|
break; |
|
|
|
msize -= rsize; |
|
rstart += rsize; |
|
} |
|
|
|
return ret; |
|
} |
|
|
|
static int __init fadump_get_boot_mem_regions(void) |
|
{ |
|
unsigned long size, cur_size, hole_size, last_end; |
|
unsigned long mem_size = fw_dump.boot_memory_size; |
|
phys_addr_t reg_start, reg_end; |
|
int ret = 1; |
|
u64 i; |
|
|
|
fw_dump.boot_mem_regs_cnt = 0; |
|
|
|
last_end = 0; |
|
hole_size = 0; |
|
cur_size = 0; |
|
for_each_mem_range(i, ®_start, ®_end) { |
|
size = reg_end - reg_start; |
|
hole_size += (reg_start - last_end); |
|
|
|
if ((cur_size + size) >= mem_size) { |
|
size = (mem_size - cur_size); |
|
ret = add_boot_mem_regions(reg_start, size); |
|
break; |
|
} |
|
|
|
mem_size -= size; |
|
cur_size += size; |
|
ret = add_boot_mem_regions(reg_start, size); |
|
if (!ret) |
|
break; |
|
|
|
last_end = reg_end; |
|
} |
|
fw_dump.boot_mem_top = PAGE_ALIGN(fw_dump.boot_memory_size + hole_size); |
|
|
|
return ret; |
|
} |
|
|
|
/* |
|
* Returns true, if the given range overlaps with reserved memory ranges |
|
* starting at idx. Also, updates idx to index of overlapping memory range |
|
* with the given memory range. |
|
* False, otherwise. |
|
*/ |
|
static bool overlaps_reserved_ranges(u64 base, u64 end, int *idx) |
|
{ |
|
bool ret = false; |
|
int i; |
|
|
|
for (i = *idx; i < reserved_mrange_info.mem_range_cnt; i++) { |
|
u64 rbase = reserved_mrange_info.mem_ranges[i].base; |
|
u64 rend = rbase + reserved_mrange_info.mem_ranges[i].size; |
|
|
|
if (end <= rbase) |
|
break; |
|
|
|
if ((end > rbase) && (base < rend)) { |
|
*idx = i; |
|
ret = true; |
|
break; |
|
} |
|
} |
|
|
|
return ret; |
|
} |
|
|
|
/* |
|
* Locate a suitable memory area to reserve memory for FADump. While at it, |
|
* lookup reserved-ranges & avoid overlap with them, as they are used by F/W. |
|
*/ |
|
static u64 __init fadump_locate_reserve_mem(u64 base, u64 size) |
|
{ |
|
struct fadump_memory_range *mrngs; |
|
phys_addr_t mstart, mend; |
|
int idx = 0; |
|
u64 i, ret = 0; |
|
|
|
mrngs = reserved_mrange_info.mem_ranges; |
|
for_each_free_mem_range(i, NUMA_NO_NODE, MEMBLOCK_NONE, |
|
&mstart, &mend, NULL) { |
|
pr_debug("%llu) mstart: %llx, mend: %llx, base: %llx\n", |
|
i, mstart, mend, base); |
|
|
|
if (mstart > base) |
|
base = PAGE_ALIGN(mstart); |
|
|
|
while ((mend > base) && ((mend - base) >= size)) { |
|
if (!overlaps_reserved_ranges(base, base+size, &idx)) { |
|
ret = base; |
|
goto out; |
|
} |
|
|
|
base = mrngs[idx].base + mrngs[idx].size; |
|
base = PAGE_ALIGN(base); |
|
} |
|
} |
|
|
|
out: |
|
return ret; |
|
} |
|
|
|
int __init fadump_reserve_mem(void) |
|
{ |
|
u64 base, size, mem_boundary, bootmem_min; |
|
int ret = 1; |
|
|
|
if (!fw_dump.fadump_enabled) |
|
return 0; |
|
|
|
if (!fw_dump.fadump_supported) { |
|
pr_info("Firmware-Assisted Dump is not supported on this hardware\n"); |
|
goto error_out; |
|
} |
|
|
|
/* |
|
* Initialize boot memory size |
|
* If dump is active then we have already calculated the size during |
|
* first kernel. |
|
*/ |
|
if (!fw_dump.dump_active) { |
|
fw_dump.boot_memory_size = |
|
PAGE_ALIGN(fadump_calculate_reserve_size()); |
|
#ifdef CONFIG_CMA |
|
if (!fw_dump.nocma) { |
|
fw_dump.boot_memory_size = |
|
ALIGN(fw_dump.boot_memory_size, |
|
FADUMP_CMA_ALIGNMENT); |
|
} |
|
#endif |
|
|
|
bootmem_min = fw_dump.ops->fadump_get_bootmem_min(); |
|
if (fw_dump.boot_memory_size < bootmem_min) { |
|
pr_err("Can't enable fadump with boot memory size (0x%lx) less than 0x%llx\n", |
|
fw_dump.boot_memory_size, bootmem_min); |
|
goto error_out; |
|
} |
|
|
|
if (!fadump_get_boot_mem_regions()) { |
|
pr_err("Too many holes in boot memory area to enable fadump\n"); |
|
goto error_out; |
|
} |
|
} |
|
|
|
/* |
|
* Calculate the memory boundary. |
|
* If memory_limit is less than actual memory boundary then reserve |
|
* the memory for fadump beyond the memory_limit and adjust the |
|
* memory_limit accordingly, so that the running kernel can run with |
|
* specified memory_limit. |
|
*/ |
|
if (memory_limit && memory_limit < memblock_end_of_DRAM()) { |
|
size = get_fadump_area_size(); |
|
if ((memory_limit + size) < memblock_end_of_DRAM()) |
|
memory_limit += size; |
|
else |
|
memory_limit = memblock_end_of_DRAM(); |
|
printk(KERN_INFO "Adjusted memory_limit for firmware-assisted" |
|
" dump, now %#016llx\n", memory_limit); |
|
} |
|
if (memory_limit) |
|
mem_boundary = memory_limit; |
|
else |
|
mem_boundary = memblock_end_of_DRAM(); |
|
|
|
base = fw_dump.boot_mem_top; |
|
size = get_fadump_area_size(); |
|
fw_dump.reserve_dump_area_size = size; |
|
if (fw_dump.dump_active) { |
|
pr_info("Firmware-assisted dump is active.\n"); |
|
|
|
#ifdef CONFIG_HUGETLB_PAGE |
|
/* |
|
* FADump capture kernel doesn't care much about hugepages. |
|
* In fact, handling hugepages in capture kernel is asking for |
|
* trouble. So, disable HugeTLB support when fadump is active. |
|
*/ |
|
hugetlb_disabled = true; |
|
#endif |
|
/* |
|
* If last boot has crashed then reserve all the memory |
|
* above boot memory size so that we don't touch it until |
|
* dump is written to disk by userspace tool. This memory |
|
* can be released for general use by invalidating fadump. |
|
*/ |
|
fadump_reserve_crash_area(base); |
|
|
|
pr_debug("fadumphdr_addr = %#016lx\n", fw_dump.fadumphdr_addr); |
|
pr_debug("Reserve dump area start address: 0x%lx\n", |
|
fw_dump.reserve_dump_area_start); |
|
} else { |
|
/* |
|
* Reserve memory at an offset closer to bottom of the RAM to |
|
* minimize the impact of memory hot-remove operation. |
|
*/ |
|
base = fadump_locate_reserve_mem(base, size); |
|
|
|
if (!base || (base + size > mem_boundary)) { |
|
pr_err("Failed to find memory chunk for reservation!\n"); |
|
goto error_out; |
|
} |
|
fw_dump.reserve_dump_area_start = base; |
|
|
|
/* |
|
* Calculate the kernel metadata address and register it with |
|
* f/w if the platform supports. |
|
*/ |
|
if (fw_dump.ops->fadump_setup_metadata && |
|
(fw_dump.ops->fadump_setup_metadata(&fw_dump) < 0)) |
|
goto error_out; |
|
|
|
if (memblock_reserve(base, size)) { |
|
pr_err("Failed to reserve memory!\n"); |
|
goto error_out; |
|
} |
|
|
|
pr_info("Reserved %lldMB of memory at %#016llx (System RAM: %lldMB)\n", |
|
(size >> 20), base, (memblock_phys_mem_size() >> 20)); |
|
|
|
ret = fadump_cma_init(); |
|
} |
|
|
|
return ret; |
|
error_out: |
|
fw_dump.fadump_enabled = 0; |
|
return 0; |
|
} |
|
|
|
/* Look for fadump= cmdline option. */ |
|
static int __init early_fadump_param(char *p) |
|
{ |
|
if (!p) |
|
return 1; |
|
|
|
if (strncmp(p, "on", 2) == 0) |
|
fw_dump.fadump_enabled = 1; |
|
else if (strncmp(p, "off", 3) == 0) |
|
fw_dump.fadump_enabled = 0; |
|
else if (strncmp(p, "nocma", 5) == 0) { |
|
fw_dump.fadump_enabled = 1; |
|
fw_dump.nocma = 1; |
|
} |
|
|
|
return 0; |
|
} |
|
early_param("fadump", early_fadump_param); |
|
|
|
/* |
|
* Look for fadump_reserve_mem= cmdline option |
|
* TODO: Remove references to 'fadump_reserve_mem=' parameter, |
|
* the sooner 'crashkernel=' parameter is accustomed to. |
|
*/ |
|
static int __init early_fadump_reserve_mem(char *p) |
|
{ |
|
if (p) |
|
fw_dump.reserve_bootvar = memparse(p, &p); |
|
return 0; |
|
} |
|
early_param("fadump_reserve_mem", early_fadump_reserve_mem); |
|
|
|
void crash_fadump(struct pt_regs *regs, const char *str) |
|
{ |
|
unsigned int msecs; |
|
struct fadump_crash_info_header *fdh = NULL; |
|
int old_cpu, this_cpu; |
|
/* Do not include first CPU */ |
|
unsigned int ncpus = num_online_cpus() - 1; |
|
|
|
if (!should_fadump_crash()) |
|
return; |
|
|
|
/* |
|
* old_cpu == -1 means this is the first CPU which has come here, |
|
* go ahead and trigger fadump. |
|
* |
|
* old_cpu != -1 means some other CPU has already on it's way |
|
* to trigger fadump, just keep looping here. |
|
*/ |
|
this_cpu = smp_processor_id(); |
|
old_cpu = cmpxchg(&crashing_cpu, -1, this_cpu); |
|
|
|
if (old_cpu != -1) { |
|
atomic_inc(&cpus_in_fadump); |
|
|
|
/* |
|
* We can't loop here indefinitely. Wait as long as fadump |
|
* is in force. If we race with fadump un-registration this |
|
* loop will break and then we go down to normal panic path |
|
* and reboot. If fadump is in force the first crashing |
|
* cpu will definitely trigger fadump. |
|
*/ |
|
while (fw_dump.dump_registered) |
|
cpu_relax(); |
|
return; |
|
} |
|
|
|
fdh = __va(fw_dump.fadumphdr_addr); |
|
fdh->crashing_cpu = crashing_cpu; |
|
crash_save_vmcoreinfo(); |
|
|
|
if (regs) |
|
fdh->regs = *regs; |
|
else |
|
ppc_save_regs(&fdh->regs); |
|
|
|
fdh->online_mask = *cpu_online_mask; |
|
|
|
/* |
|
* If we came in via system reset, wait a while for the secondary |
|
* CPUs to enter. |
|
*/ |
|
if (TRAP(&(fdh->regs)) == 0x100) { |
|
msecs = CRASH_TIMEOUT; |
|
while ((atomic_read(&cpus_in_fadump) < ncpus) && (--msecs > 0)) |
|
mdelay(1); |
|
} |
|
|
|
fw_dump.ops->fadump_trigger(fdh, str); |
|
} |
|
|
|
u32 *fadump_regs_to_elf_notes(u32 *buf, struct pt_regs *regs) |
|
{ |
|
struct elf_prstatus prstatus; |
|
|
|
memset(&prstatus, 0, sizeof(prstatus)); |
|
/* |
|
* FIXME: How do i get PID? Do I really need it? |
|
* prstatus.pr_pid = ???? |
|
*/ |
|
elf_core_copy_kernel_regs(&prstatus.pr_reg, regs); |
|
buf = append_elf_note(buf, CRASH_CORE_NOTE_NAME, NT_PRSTATUS, |
|
&prstatus, sizeof(prstatus)); |
|
return buf; |
|
} |
|
|
|
void fadump_update_elfcore_header(char *bufp) |
|
{ |
|
struct elf_phdr *phdr; |
|
|
|
bufp += sizeof(struct elfhdr); |
|
|
|
/* First note is a place holder for cpu notes info. */ |
|
phdr = (struct elf_phdr *)bufp; |
|
|
|
if (phdr->p_type == PT_NOTE) { |
|
phdr->p_paddr = __pa(fw_dump.cpu_notes_buf_vaddr); |
|
phdr->p_offset = phdr->p_paddr; |
|
phdr->p_filesz = fw_dump.cpu_notes_buf_size; |
|
phdr->p_memsz = fw_dump.cpu_notes_buf_size; |
|
} |
|
return; |
|
} |
|
|
|
static void *fadump_alloc_buffer(unsigned long size) |
|
{ |
|
unsigned long count, i; |
|
struct page *page; |
|
void *vaddr; |
|
|
|
vaddr = alloc_pages_exact(size, GFP_KERNEL | __GFP_ZERO); |
|
if (!vaddr) |
|
return NULL; |
|
|
|
count = PAGE_ALIGN(size) / PAGE_SIZE; |
|
page = virt_to_page(vaddr); |
|
for (i = 0; i < count; i++) |
|
mark_page_reserved(page + i); |
|
return vaddr; |
|
} |
|
|
|
static void fadump_free_buffer(unsigned long vaddr, unsigned long size) |
|
{ |
|
free_reserved_area((void *)vaddr, (void *)(vaddr + size), -1, NULL); |
|
} |
|
|
|
s32 fadump_setup_cpu_notes_buf(u32 num_cpus) |
|
{ |
|
/* Allocate buffer to hold cpu crash notes. */ |
|
fw_dump.cpu_notes_buf_size = num_cpus * sizeof(note_buf_t); |
|
fw_dump.cpu_notes_buf_size = PAGE_ALIGN(fw_dump.cpu_notes_buf_size); |
|
fw_dump.cpu_notes_buf_vaddr = |
|
(unsigned long)fadump_alloc_buffer(fw_dump.cpu_notes_buf_size); |
|
if (!fw_dump.cpu_notes_buf_vaddr) { |
|
pr_err("Failed to allocate %ld bytes for CPU notes buffer\n", |
|
fw_dump.cpu_notes_buf_size); |
|
return -ENOMEM; |
|
} |
|
|
|
pr_debug("Allocated buffer for cpu notes of size %ld at 0x%lx\n", |
|
fw_dump.cpu_notes_buf_size, |
|
fw_dump.cpu_notes_buf_vaddr); |
|
return 0; |
|
} |
|
|
|
void fadump_free_cpu_notes_buf(void) |
|
{ |
|
if (!fw_dump.cpu_notes_buf_vaddr) |
|
return; |
|
|
|
fadump_free_buffer(fw_dump.cpu_notes_buf_vaddr, |
|
fw_dump.cpu_notes_buf_size); |
|
fw_dump.cpu_notes_buf_vaddr = 0; |
|
fw_dump.cpu_notes_buf_size = 0; |
|
} |
|
|
|
static void fadump_free_mem_ranges(struct fadump_mrange_info *mrange_info) |
|
{ |
|
if (mrange_info->is_static) { |
|
mrange_info->mem_range_cnt = 0; |
|
return; |
|
} |
|
|
|
kfree(mrange_info->mem_ranges); |
|
memset((void *)((u64)mrange_info + RNG_NAME_SZ), 0, |
|
(sizeof(struct fadump_mrange_info) - RNG_NAME_SZ)); |
|
} |
|
|
|
/* |
|
* Allocate or reallocate mem_ranges array in incremental units |
|
* of PAGE_SIZE. |
|
*/ |
|
static int fadump_alloc_mem_ranges(struct fadump_mrange_info *mrange_info) |
|
{ |
|
struct fadump_memory_range *new_array; |
|
u64 new_size; |
|
|
|
new_size = mrange_info->mem_ranges_sz + PAGE_SIZE; |
|
pr_debug("Allocating %llu bytes of memory for %s memory ranges\n", |
|
new_size, mrange_info->name); |
|
|
|
new_array = krealloc(mrange_info->mem_ranges, new_size, GFP_KERNEL); |
|
if (new_array == NULL) { |
|
pr_err("Insufficient memory for setting up %s memory ranges\n", |
|
mrange_info->name); |
|
fadump_free_mem_ranges(mrange_info); |
|
return -ENOMEM; |
|
} |
|
|
|
mrange_info->mem_ranges = new_array; |
|
mrange_info->mem_ranges_sz = new_size; |
|
mrange_info->max_mem_ranges = (new_size / |
|
sizeof(struct fadump_memory_range)); |
|
return 0; |
|
} |
|
|
|
static inline int fadump_add_mem_range(struct fadump_mrange_info *mrange_info, |
|
u64 base, u64 end) |
|
{ |
|
struct fadump_memory_range *mem_ranges = mrange_info->mem_ranges; |
|
bool is_adjacent = false; |
|
u64 start, size; |
|
|
|
if (base == end) |
|
return 0; |
|
|
|
/* |
|
* Fold adjacent memory ranges to bring down the memory ranges/ |
|
* PT_LOAD segments count. |
|
*/ |
|
if (mrange_info->mem_range_cnt) { |
|
start = mem_ranges[mrange_info->mem_range_cnt - 1].base; |
|
size = mem_ranges[mrange_info->mem_range_cnt - 1].size; |
|
|
|
if ((start + size) == base) |
|
is_adjacent = true; |
|
} |
|
if (!is_adjacent) { |
|
/* resize the array on reaching the limit */ |
|
if (mrange_info->mem_range_cnt == mrange_info->max_mem_ranges) { |
|
int ret; |
|
|
|
if (mrange_info->is_static) { |
|
pr_err("Reached array size limit for %s memory ranges\n", |
|
mrange_info->name); |
|
return -ENOSPC; |
|
} |
|
|
|
ret = fadump_alloc_mem_ranges(mrange_info); |
|
if (ret) |
|
return ret; |
|
|
|
/* Update to the new resized array */ |
|
mem_ranges = mrange_info->mem_ranges; |
|
} |
|
|
|
start = base; |
|
mem_ranges[mrange_info->mem_range_cnt].base = start; |
|
mrange_info->mem_range_cnt++; |
|
} |
|
|
|
mem_ranges[mrange_info->mem_range_cnt - 1].size = (end - start); |
|
pr_debug("%s_memory_range[%d] [%#016llx-%#016llx], %#llx bytes\n", |
|
mrange_info->name, (mrange_info->mem_range_cnt - 1), |
|
start, end - 1, (end - start)); |
|
return 0; |
|
} |
|
|
|
static int fadump_exclude_reserved_area(u64 start, u64 end) |
|
{ |
|
u64 ra_start, ra_end; |
|
int ret = 0; |
|
|
|
ra_start = fw_dump.reserve_dump_area_start; |
|
ra_end = ra_start + fw_dump.reserve_dump_area_size; |
|
|
|
if ((ra_start < end) && (ra_end > start)) { |
|
if ((start < ra_start) && (end > ra_end)) { |
|
ret = fadump_add_mem_range(&crash_mrange_info, |
|
start, ra_start); |
|
if (ret) |
|
return ret; |
|
|
|
ret = fadump_add_mem_range(&crash_mrange_info, |
|
ra_end, end); |
|
} else if (start < ra_start) { |
|
ret = fadump_add_mem_range(&crash_mrange_info, |
|
start, ra_start); |
|
} else if (ra_end < end) { |
|
ret = fadump_add_mem_range(&crash_mrange_info, |
|
ra_end, end); |
|
} |
|
} else |
|
ret = fadump_add_mem_range(&crash_mrange_info, start, end); |
|
|
|
return ret; |
|
} |
|
|
|
static int fadump_init_elfcore_header(char *bufp) |
|
{ |
|
struct elfhdr *elf; |
|
|
|
elf = (struct elfhdr *) bufp; |
|
bufp += sizeof(struct elfhdr); |
|
memcpy(elf->e_ident, ELFMAG, SELFMAG); |
|
elf->e_ident[EI_CLASS] = ELF_CLASS; |
|
elf->e_ident[EI_DATA] = ELF_DATA; |
|
elf->e_ident[EI_VERSION] = EV_CURRENT; |
|
elf->e_ident[EI_OSABI] = ELF_OSABI; |
|
memset(elf->e_ident+EI_PAD, 0, EI_NIDENT-EI_PAD); |
|
elf->e_type = ET_CORE; |
|
elf->e_machine = ELF_ARCH; |
|
elf->e_version = EV_CURRENT; |
|
elf->e_entry = 0; |
|
elf->e_phoff = sizeof(struct elfhdr); |
|
elf->e_shoff = 0; |
|
#if defined(_CALL_ELF) |
|
elf->e_flags = _CALL_ELF; |
|
#else |
|
elf->e_flags = 0; |
|
#endif |
|
elf->e_ehsize = sizeof(struct elfhdr); |
|
elf->e_phentsize = sizeof(struct elf_phdr); |
|
elf->e_phnum = 0; |
|
elf->e_shentsize = 0; |
|
elf->e_shnum = 0; |
|
elf->e_shstrndx = 0; |
|
|
|
return 0; |
|
} |
|
|
|
/* |
|
* Traverse through memblock structure and setup crash memory ranges. These |
|
* ranges will be used create PT_LOAD program headers in elfcore header. |
|
*/ |
|
static int fadump_setup_crash_memory_ranges(void) |
|
{ |
|
u64 i, start, end; |
|
int ret; |
|
|
|
pr_debug("Setup crash memory ranges.\n"); |
|
crash_mrange_info.mem_range_cnt = 0; |
|
|
|
/* |
|
* Boot memory region(s) registered with firmware are moved to |
|
* different location at the time of crash. Create separate program |
|
* header(s) for this memory chunk(s) with the correct offset. |
|
*/ |
|
for (i = 0; i < fw_dump.boot_mem_regs_cnt; i++) { |
|
start = fw_dump.boot_mem_addr[i]; |
|
end = start + fw_dump.boot_mem_sz[i]; |
|
ret = fadump_add_mem_range(&crash_mrange_info, start, end); |
|
if (ret) |
|
return ret; |
|
} |
|
|
|
for_each_mem_range(i, &start, &end) { |
|
/* |
|
* skip the memory chunk that is already added |
|
* (0 through boot_memory_top). |
|
*/ |
|
if (start < fw_dump.boot_mem_top) { |
|
if (end > fw_dump.boot_mem_top) |
|
start = fw_dump.boot_mem_top; |
|
else |
|
continue; |
|
} |
|
|
|
/* add this range excluding the reserved dump area. */ |
|
ret = fadump_exclude_reserved_area(start, end); |
|
if (ret) |
|
return ret; |
|
} |
|
|
|
return 0; |
|
} |
|
|
|
/* |
|
* If the given physical address falls within the boot memory region then |
|
* return the relocated address that points to the dump region reserved |
|
* for saving initial boot memory contents. |
|
*/ |
|
static inline unsigned long fadump_relocate(unsigned long paddr) |
|
{ |
|
unsigned long raddr, rstart, rend, rlast, hole_size; |
|
int i; |
|
|
|
hole_size = 0; |
|
rlast = 0; |
|
raddr = paddr; |
|
for (i = 0; i < fw_dump.boot_mem_regs_cnt; i++) { |
|
rstart = fw_dump.boot_mem_addr[i]; |
|
rend = rstart + fw_dump.boot_mem_sz[i]; |
|
hole_size += (rstart - rlast); |
|
|
|
if (paddr >= rstart && paddr < rend) { |
|
raddr += fw_dump.boot_mem_dest_addr - hole_size; |
|
break; |
|
} |
|
|
|
rlast = rend; |
|
} |
|
|
|
pr_debug("vmcoreinfo: paddr = 0x%lx, raddr = 0x%lx\n", paddr, raddr); |
|
return raddr; |
|
} |
|
|
|
static int fadump_create_elfcore_headers(char *bufp) |
|
{ |
|
unsigned long long raddr, offset; |
|
struct elf_phdr *phdr; |
|
struct elfhdr *elf; |
|
int i, j; |
|
|
|
fadump_init_elfcore_header(bufp); |
|
elf = (struct elfhdr *)bufp; |
|
bufp += sizeof(struct elfhdr); |
|
|
|
/* |
|
* setup ELF PT_NOTE, place holder for cpu notes info. The notes info |
|
* will be populated during second kernel boot after crash. Hence |
|
* this PT_NOTE will always be the first elf note. |
|
* |
|
* NOTE: Any new ELF note addition should be placed after this note. |
|
*/ |
|
phdr = (struct elf_phdr *)bufp; |
|
bufp += sizeof(struct elf_phdr); |
|
phdr->p_type = PT_NOTE; |
|
phdr->p_flags = 0; |
|
phdr->p_vaddr = 0; |
|
phdr->p_align = 0; |
|
|
|
phdr->p_offset = 0; |
|
phdr->p_paddr = 0; |
|
phdr->p_filesz = 0; |
|
phdr->p_memsz = 0; |
|
|
|
(elf->e_phnum)++; |
|
|
|
/* setup ELF PT_NOTE for vmcoreinfo */ |
|
phdr = (struct elf_phdr *)bufp; |
|
bufp += sizeof(struct elf_phdr); |
|
phdr->p_type = PT_NOTE; |
|
phdr->p_flags = 0; |
|
phdr->p_vaddr = 0; |
|
phdr->p_align = 0; |
|
|
|
phdr->p_paddr = fadump_relocate(paddr_vmcoreinfo_note()); |
|
phdr->p_offset = phdr->p_paddr; |
|
phdr->p_memsz = phdr->p_filesz = VMCOREINFO_NOTE_SIZE; |
|
|
|
/* Increment number of program headers. */ |
|
(elf->e_phnum)++; |
|
|
|
/* setup PT_LOAD sections. */ |
|
j = 0; |
|
offset = 0; |
|
raddr = fw_dump.boot_mem_addr[0]; |
|
for (i = 0; i < crash_mrange_info.mem_range_cnt; i++) { |
|
u64 mbase, msize; |
|
|
|
mbase = crash_mrange_info.mem_ranges[i].base; |
|
msize = crash_mrange_info.mem_ranges[i].size; |
|
if (!msize) |
|
continue; |
|
|
|
phdr = (struct elf_phdr *)bufp; |
|
bufp += sizeof(struct elf_phdr); |
|
phdr->p_type = PT_LOAD; |
|
phdr->p_flags = PF_R|PF_W|PF_X; |
|
phdr->p_offset = mbase; |
|
|
|
if (mbase == raddr) { |
|
/* |
|
* The entire real memory region will be moved by |
|
* firmware to the specified destination_address. |
|
* Hence set the correct offset. |
|
*/ |
|
phdr->p_offset = fw_dump.boot_mem_dest_addr + offset; |
|
if (j < (fw_dump.boot_mem_regs_cnt - 1)) { |
|
offset += fw_dump.boot_mem_sz[j]; |
|
raddr = fw_dump.boot_mem_addr[++j]; |
|
} |
|
} |
|
|
|
phdr->p_paddr = mbase; |
|
phdr->p_vaddr = (unsigned long)__va(mbase); |
|
phdr->p_filesz = msize; |
|
phdr->p_memsz = msize; |
|
phdr->p_align = 0; |
|
|
|
/* Increment number of program headers. */ |
|
(elf->e_phnum)++; |
|
} |
|
return 0; |
|
} |
|
|
|
static unsigned long init_fadump_header(unsigned long addr) |
|
{ |
|
struct fadump_crash_info_header *fdh; |
|
|
|
if (!addr) |
|
return 0; |
|
|
|
fdh = __va(addr); |
|
addr += sizeof(struct fadump_crash_info_header); |
|
|
|
memset(fdh, 0, sizeof(struct fadump_crash_info_header)); |
|
fdh->magic_number = FADUMP_CRASH_INFO_MAGIC; |
|
fdh->elfcorehdr_addr = addr; |
|
/* We will set the crashing cpu id in crash_fadump() during crash. */ |
|
fdh->crashing_cpu = FADUMP_CPU_UNKNOWN; |
|
|
|
return addr; |
|
} |
|
|
|
static int register_fadump(void) |
|
{ |
|
unsigned long addr; |
|
void *vaddr; |
|
int ret; |
|
|
|
/* |
|
* If no memory is reserved then we can not register for firmware- |
|
* assisted dump. |
|
*/ |
|
if (!fw_dump.reserve_dump_area_size) |
|
return -ENODEV; |
|
|
|
ret = fadump_setup_crash_memory_ranges(); |
|
if (ret) |
|
return ret; |
|
|
|
addr = fw_dump.fadumphdr_addr; |
|
|
|
/* Initialize fadump crash info header. */ |
|
addr = init_fadump_header(addr); |
|
vaddr = __va(addr); |
|
|
|
pr_debug("Creating ELF core headers at %#016lx\n", addr); |
|
fadump_create_elfcore_headers(vaddr); |
|
|
|
/* register the future kernel dump with firmware. */ |
|
pr_debug("Registering for firmware-assisted kernel dump...\n"); |
|
return fw_dump.ops->fadump_register(&fw_dump); |
|
} |
|
|
|
void fadump_cleanup(void) |
|
{ |
|
if (!fw_dump.fadump_supported) |
|
return; |
|
|
|
/* Invalidate the registration only if dump is active. */ |
|
if (fw_dump.dump_active) { |
|
pr_debug("Invalidating firmware-assisted dump registration\n"); |
|
fw_dump.ops->fadump_invalidate(&fw_dump); |
|
} else if (fw_dump.dump_registered) { |
|
/* Un-register Firmware-assisted dump if it was registered. */ |
|
fw_dump.ops->fadump_unregister(&fw_dump); |
|
fadump_free_mem_ranges(&crash_mrange_info); |
|
} |
|
|
|
if (fw_dump.ops->fadump_cleanup) |
|
fw_dump.ops->fadump_cleanup(&fw_dump); |
|
} |
|
|
|
static void fadump_free_reserved_memory(unsigned long start_pfn, |
|
unsigned long end_pfn) |
|
{ |
|
unsigned long pfn; |
|
unsigned long time_limit = jiffies + HZ; |
|
|
|
pr_info("freeing reserved memory (0x%llx - 0x%llx)\n", |
|
PFN_PHYS(start_pfn), PFN_PHYS(end_pfn)); |
|
|
|
for (pfn = start_pfn; pfn < end_pfn; pfn++) { |
|
free_reserved_page(pfn_to_page(pfn)); |
|
|
|
if (time_after(jiffies, time_limit)) { |
|
cond_resched(); |
|
time_limit = jiffies + HZ; |
|
} |
|
} |
|
} |
|
|
|
/* |
|
* Skip memory holes and free memory that was actually reserved. |
|
*/ |
|
static void fadump_release_reserved_area(u64 start, u64 end) |
|
{ |
|
unsigned long reg_spfn, reg_epfn; |
|
u64 tstart, tend, spfn, epfn; |
|
int i; |
|
|
|
spfn = PHYS_PFN(start); |
|
epfn = PHYS_PFN(end); |
|
|
|
for_each_mem_pfn_range(i, MAX_NUMNODES, ®_spfn, ®_epfn, NULL) { |
|
tstart = max_t(u64, spfn, reg_spfn); |
|
tend = min_t(u64, epfn, reg_epfn); |
|
|
|
if (tstart < tend) { |
|
fadump_free_reserved_memory(tstart, tend); |
|
|
|
if (tend == epfn) |
|
break; |
|
|
|
spfn = tend; |
|
} |
|
} |
|
} |
|
|
|
/* |
|
* Sort the mem ranges in-place and merge adjacent ranges |
|
* to minimize the memory ranges count. |
|
*/ |
|
static void sort_and_merge_mem_ranges(struct fadump_mrange_info *mrange_info) |
|
{ |
|
struct fadump_memory_range *mem_ranges; |
|
struct fadump_memory_range tmp_range; |
|
u64 base, size; |
|
int i, j, idx; |
|
|
|
if (!reserved_mrange_info.mem_range_cnt) |
|
return; |
|
|
|
/* Sort the memory ranges */ |
|
mem_ranges = mrange_info->mem_ranges; |
|
for (i = 0; i < mrange_info->mem_range_cnt; i++) { |
|
idx = i; |
|
for (j = (i + 1); j < mrange_info->mem_range_cnt; j++) { |
|
if (mem_ranges[idx].base > mem_ranges[j].base) |
|
idx = j; |
|
} |
|
if (idx != i) { |
|
tmp_range = mem_ranges[idx]; |
|
mem_ranges[idx] = mem_ranges[i]; |
|
mem_ranges[i] = tmp_range; |
|
} |
|
} |
|
|
|
/* Merge adjacent reserved ranges */ |
|
idx = 0; |
|
for (i = 1; i < mrange_info->mem_range_cnt; i++) { |
|
base = mem_ranges[i-1].base; |
|
size = mem_ranges[i-1].size; |
|
if (mem_ranges[i].base == (base + size)) |
|
mem_ranges[idx].size += mem_ranges[i].size; |
|
else { |
|
idx++; |
|
if (i == idx) |
|
continue; |
|
|
|
mem_ranges[idx] = mem_ranges[i]; |
|
} |
|
} |
|
mrange_info->mem_range_cnt = idx + 1; |
|
} |
|
|
|
/* |
|
* Scan reserved-ranges to consider them while reserving/releasing |
|
* memory for FADump. |
|
*/ |
|
static void __init early_init_dt_scan_reserved_ranges(unsigned long node) |
|
{ |
|
const __be32 *prop; |
|
int len, ret = -1; |
|
unsigned long i; |
|
|
|
/* reserved-ranges already scanned */ |
|
if (reserved_mrange_info.mem_range_cnt != 0) |
|
return; |
|
|
|
prop = of_get_flat_dt_prop(node, "reserved-ranges", &len); |
|
if (!prop) |
|
return; |
|
|
|
/* |
|
* Each reserved range is an (address,size) pair, 2 cells each, |
|
* totalling 4 cells per range. |
|
*/ |
|
for (i = 0; i < len / (sizeof(*prop) * 4); i++) { |
|
u64 base, size; |
|
|
|
base = of_read_number(prop + (i * 4) + 0, 2); |
|
size = of_read_number(prop + (i * 4) + 2, 2); |
|
|
|
if (size) { |
|
ret = fadump_add_mem_range(&reserved_mrange_info, |
|
base, base + size); |
|
if (ret < 0) { |
|
pr_warn("some reserved ranges are ignored!\n"); |
|
break; |
|
} |
|
} |
|
} |
|
|
|
/* Compact reserved ranges */ |
|
sort_and_merge_mem_ranges(&reserved_mrange_info); |
|
} |
|
|
|
/* |
|
* Release the memory that was reserved during early boot to preserve the |
|
* crash'ed kernel's memory contents except reserved dump area (permanent |
|
* reservation) and reserved ranges used by F/W. The released memory will |
|
* be available for general use. |
|
*/ |
|
static void fadump_release_memory(u64 begin, u64 end) |
|
{ |
|
u64 ra_start, ra_end, tstart; |
|
int i, ret; |
|
|
|
ra_start = fw_dump.reserve_dump_area_start; |
|
ra_end = ra_start + fw_dump.reserve_dump_area_size; |
|
|
|
/* |
|
* If reserved ranges array limit is hit, overwrite the last reserved |
|
* memory range with reserved dump area to ensure it is excluded from |
|
* the memory being released (reused for next FADump registration). |
|
*/ |
|
if (reserved_mrange_info.mem_range_cnt == |
|
reserved_mrange_info.max_mem_ranges) |
|
reserved_mrange_info.mem_range_cnt--; |
|
|
|
ret = fadump_add_mem_range(&reserved_mrange_info, ra_start, ra_end); |
|
if (ret != 0) |
|
return; |
|
|
|
/* Get the reserved ranges list in order first. */ |
|
sort_and_merge_mem_ranges(&reserved_mrange_info); |
|
|
|
/* Exclude reserved ranges and release remaining memory */ |
|
tstart = begin; |
|
for (i = 0; i < reserved_mrange_info.mem_range_cnt; i++) { |
|
ra_start = reserved_mrange_info.mem_ranges[i].base; |
|
ra_end = ra_start + reserved_mrange_info.mem_ranges[i].size; |
|
|
|
if (tstart >= ra_end) |
|
continue; |
|
|
|
if (tstart < ra_start) |
|
fadump_release_reserved_area(tstart, ra_start); |
|
tstart = ra_end; |
|
} |
|
|
|
if (tstart < end) |
|
fadump_release_reserved_area(tstart, end); |
|
} |
|
|
|
static void fadump_invalidate_release_mem(void) |
|
{ |
|
mutex_lock(&fadump_mutex); |
|
if (!fw_dump.dump_active) { |
|
mutex_unlock(&fadump_mutex); |
|
return; |
|
} |
|
|
|
fadump_cleanup(); |
|
mutex_unlock(&fadump_mutex); |
|
|
|
fadump_release_memory(fw_dump.boot_mem_top, memblock_end_of_DRAM()); |
|
fadump_free_cpu_notes_buf(); |
|
|
|
/* |
|
* Setup kernel metadata and initialize the kernel dump |
|
* memory structure for FADump re-registration. |
|
*/ |
|
if (fw_dump.ops->fadump_setup_metadata && |
|
(fw_dump.ops->fadump_setup_metadata(&fw_dump) < 0)) |
|
pr_warn("Failed to setup kernel metadata!\n"); |
|
fw_dump.ops->fadump_init_mem_struct(&fw_dump); |
|
} |
|
|
|
static ssize_t release_mem_store(struct kobject *kobj, |
|
struct kobj_attribute *attr, |
|
const char *buf, size_t count) |
|
{ |
|
int input = -1; |
|
|
|
if (!fw_dump.dump_active) |
|
return -EPERM; |
|
|
|
if (kstrtoint(buf, 0, &input)) |
|
return -EINVAL; |
|
|
|
if (input == 1) { |
|
/* |
|
* Take away the '/proc/vmcore'. We are releasing the dump |
|
* memory, hence it will not be valid anymore. |
|
*/ |
|
#ifdef CONFIG_PROC_VMCORE |
|
vmcore_cleanup(); |
|
#endif |
|
fadump_invalidate_release_mem(); |
|
|
|
} else |
|
return -EINVAL; |
|
return count; |
|
} |
|
|
|
/* Release the reserved memory and disable the FADump */ |
|
static void unregister_fadump(void) |
|
{ |
|
fadump_cleanup(); |
|
fadump_release_memory(fw_dump.reserve_dump_area_start, |
|
fw_dump.reserve_dump_area_size); |
|
fw_dump.fadump_enabled = 0; |
|
kobject_put(fadump_kobj); |
|
} |
|
|
|
static ssize_t enabled_show(struct kobject *kobj, |
|
struct kobj_attribute *attr, |
|
char *buf) |
|
{ |
|
return sprintf(buf, "%d\n", fw_dump.fadump_enabled); |
|
} |
|
|
|
static ssize_t mem_reserved_show(struct kobject *kobj, |
|
struct kobj_attribute *attr, |
|
char *buf) |
|
{ |
|
return sprintf(buf, "%ld\n", fw_dump.reserve_dump_area_size); |
|
} |
|
|
|
static ssize_t registered_show(struct kobject *kobj, |
|
struct kobj_attribute *attr, |
|
char *buf) |
|
{ |
|
return sprintf(buf, "%d\n", fw_dump.dump_registered); |
|
} |
|
|
|
static ssize_t registered_store(struct kobject *kobj, |
|
struct kobj_attribute *attr, |
|
const char *buf, size_t count) |
|
{ |
|
int ret = 0; |
|
int input = -1; |
|
|
|
if (!fw_dump.fadump_enabled || fw_dump.dump_active) |
|
return -EPERM; |
|
|
|
if (kstrtoint(buf, 0, &input)) |
|
return -EINVAL; |
|
|
|
mutex_lock(&fadump_mutex); |
|
|
|
switch (input) { |
|
case 0: |
|
if (fw_dump.dump_registered == 0) { |
|
goto unlock_out; |
|
} |
|
|
|
/* Un-register Firmware-assisted dump */ |
|
pr_debug("Un-register firmware-assisted dump\n"); |
|
fw_dump.ops->fadump_unregister(&fw_dump); |
|
break; |
|
case 1: |
|
if (fw_dump.dump_registered == 1) { |
|
/* Un-register Firmware-assisted dump */ |
|
fw_dump.ops->fadump_unregister(&fw_dump); |
|
} |
|
/* Register Firmware-assisted dump */ |
|
ret = register_fadump(); |
|
break; |
|
default: |
|
ret = -EINVAL; |
|
break; |
|
} |
|
|
|
unlock_out: |
|
mutex_unlock(&fadump_mutex); |
|
return ret < 0 ? ret : count; |
|
} |
|
|
|
static int fadump_region_show(struct seq_file *m, void *private) |
|
{ |
|
if (!fw_dump.fadump_enabled) |
|
return 0; |
|
|
|
mutex_lock(&fadump_mutex); |
|
fw_dump.ops->fadump_region_show(&fw_dump, m); |
|
mutex_unlock(&fadump_mutex); |
|
return 0; |
|
} |
|
|
|
static struct kobj_attribute release_attr = __ATTR_WO(release_mem); |
|
static struct kobj_attribute enable_attr = __ATTR_RO(enabled); |
|
static struct kobj_attribute register_attr = __ATTR_RW(registered); |
|
static struct kobj_attribute mem_reserved_attr = __ATTR_RO(mem_reserved); |
|
|
|
static struct attribute *fadump_attrs[] = { |
|
&enable_attr.attr, |
|
®ister_attr.attr, |
|
&mem_reserved_attr.attr, |
|
NULL, |
|
}; |
|
|
|
ATTRIBUTE_GROUPS(fadump); |
|
|
|
DEFINE_SHOW_ATTRIBUTE(fadump_region); |
|
|
|
static void fadump_init_files(void) |
|
{ |
|
int rc = 0; |
|
|
|
fadump_kobj = kobject_create_and_add("fadump", kernel_kobj); |
|
if (!fadump_kobj) { |
|
pr_err("failed to create fadump kobject\n"); |
|
return; |
|
} |
|
|
|
debugfs_create_file("fadump_region", 0444, powerpc_debugfs_root, NULL, |
|
&fadump_region_fops); |
|
|
|
if (fw_dump.dump_active) { |
|
rc = sysfs_create_file(fadump_kobj, &release_attr.attr); |
|
if (rc) |
|
pr_err("unable to create release_mem sysfs file (%d)\n", |
|
rc); |
|
} |
|
|
|
rc = sysfs_create_groups(fadump_kobj, fadump_groups); |
|
if (rc) { |
|
pr_err("sysfs group creation failed (%d), unregistering FADump", |
|
rc); |
|
unregister_fadump(); |
|
return; |
|
} |
|
|
|
/* |
|
* The FADump sysfs are moved from kernel_kobj to fadump_kobj need to |
|
* create symlink at old location to maintain backward compatibility. |
|
* |
|
* - fadump_enabled -> fadump/enabled |
|
* - fadump_registered -> fadump/registered |
|
* - fadump_release_mem -> fadump/release_mem |
|
*/ |
|
rc = compat_only_sysfs_link_entry_to_kobj(kernel_kobj, fadump_kobj, |
|
"enabled", "fadump_enabled"); |
|
if (rc) { |
|
pr_err("unable to create fadump_enabled symlink (%d)", rc); |
|
return; |
|
} |
|
|
|
rc = compat_only_sysfs_link_entry_to_kobj(kernel_kobj, fadump_kobj, |
|
"registered", |
|
"fadump_registered"); |
|
if (rc) { |
|
pr_err("unable to create fadump_registered symlink (%d)", rc); |
|
sysfs_remove_link(kernel_kobj, "fadump_enabled"); |
|
return; |
|
} |
|
|
|
if (fw_dump.dump_active) { |
|
rc = compat_only_sysfs_link_entry_to_kobj(kernel_kobj, |
|
fadump_kobj, |
|
"release_mem", |
|
"fadump_release_mem"); |
|
if (rc) |
|
pr_err("unable to create fadump_release_mem symlink (%d)", |
|
rc); |
|
} |
|
return; |
|
} |
|
|
|
/* |
|
* Prepare for firmware-assisted dump. |
|
*/ |
|
int __init setup_fadump(void) |
|
{ |
|
if (!fw_dump.fadump_supported) |
|
return 0; |
|
|
|
fadump_init_files(); |
|
fadump_show_config(); |
|
|
|
if (!fw_dump.fadump_enabled) |
|
return 1; |
|
|
|
/* |
|
* If dump data is available then see if it is valid and prepare for |
|
* saving it to the disk. |
|
*/ |
|
if (fw_dump.dump_active) { |
|
/* |
|
* if dump process fails then invalidate the registration |
|
* and release memory before proceeding for re-registration. |
|
*/ |
|
if (fw_dump.ops->fadump_process(&fw_dump) < 0) |
|
fadump_invalidate_release_mem(); |
|
} |
|
/* Initialize the kernel dump memory structure for FAD registration. */ |
|
else if (fw_dump.reserve_dump_area_size) |
|
fw_dump.ops->fadump_init_mem_struct(&fw_dump); |
|
|
|
return 1; |
|
} |
|
subsys_initcall(setup_fadump); |
|
#else /* !CONFIG_PRESERVE_FA_DUMP */ |
|
|
|
/* Scan the Firmware Assisted dump configuration details. */ |
|
int __init early_init_dt_scan_fw_dump(unsigned long node, const char *uname, |
|
int depth, void *data) |
|
{ |
|
if ((depth != 1) || (strcmp(uname, "ibm,opal") != 0)) |
|
return 0; |
|
|
|
opal_fadump_dt_scan(&fw_dump, node); |
|
return 1; |
|
} |
|
|
|
/* |
|
* When dump is active but PRESERVE_FA_DUMP is enabled on the kernel, |
|
* preserve crash data. The subsequent memory preserving kernel boot |
|
* is likely to process this crash data. |
|
*/ |
|
int __init fadump_reserve_mem(void) |
|
{ |
|
if (fw_dump.dump_active) { |
|
/* |
|
* If last boot has crashed then reserve all the memory |
|
* above boot memory to preserve crash data. |
|
*/ |
|
pr_info("Preserving crash data for processing in next boot.\n"); |
|
fadump_reserve_crash_area(fw_dump.boot_mem_top); |
|
} else |
|
pr_debug("FADump-aware kernel..\n"); |
|
|
|
return 1; |
|
} |
|
#endif /* CONFIG_PRESERVE_FA_DUMP */ |
|
|
|
/* Preserve everything above the base address */ |
|
static void __init fadump_reserve_crash_area(u64 base) |
|
{ |
|
u64 i, mstart, mend, msize; |
|
|
|
for_each_mem_range(i, &mstart, &mend) { |
|
msize = mend - mstart; |
|
|
|
if ((mstart + msize) < base) |
|
continue; |
|
|
|
if (mstart < base) { |
|
msize -= (base - mstart); |
|
mstart = base; |
|
} |
|
|
|
pr_info("Reserving %lluMB of memory at %#016llx for preserving crash data", |
|
(msize >> 20), mstart); |
|
memblock_reserve(mstart, msize); |
|
} |
|
} |
|
|
|
unsigned long __init arch_reserved_kernel_pages(void) |
|
{ |
|
return memblock_reserved_size() / PAGE_SIZE; |
|
}
|
|
|