| /* |
| * RAM Oops/Panic logger |
| * |
| * Copyright (C) 2010 Marco Stornelli <marco.stornelli@gmail.com> |
| * |
| * This program is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU General Public License |
| * 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. |
| * |
| * 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., 51 Franklin St, Fifth Floor, Boston, MA |
| * 02110-1301 USA |
| * |
| */ |
| |
| #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
| |
| #include <linux/kernel.h> |
| #include <linux/err.h> |
| #include <linux/module.h> |
| #include <linux/kmsg_dump.h> |
| #include <linux/time.h> |
| #include <linux/io.h> |
| #include <linux/ioport.h> |
| #include <linux/platform_device.h> |
| #include <linux/slab.h> |
| #include <linux/ramoops.h> |
| |
| #define RAMOOPS_KERNMSG_HDR "====" |
| #define MIN_MEM_SIZE 4096UL |
| |
| static ulong record_size = MIN_MEM_SIZE; |
| module_param(record_size, ulong, 0400); |
| MODULE_PARM_DESC(record_size, |
| "size of each dump done on oops/panic"); |
| |
| static ulong mem_address; |
| module_param(mem_address, ulong, 0400); |
| MODULE_PARM_DESC(mem_address, |
| "start of reserved RAM used to store oops/panic logs"); |
| |
| static ulong mem_size; |
| module_param(mem_size, ulong, 0400); |
| MODULE_PARM_DESC(mem_size, |
| "size of reserved RAM used to store oops/panic logs"); |
| |
| static int dump_oops = 1; |
| module_param(dump_oops, int, 0600); |
| MODULE_PARM_DESC(dump_oops, |
| "set to 1 to dump oopses, 0 to only dump panics (default 1)"); |
| |
| static struct ramoops_context { |
| struct kmsg_dumper dump; |
| void *virt_addr; |
| phys_addr_t phys_addr; |
| unsigned long size; |
| unsigned long record_size; |
| int dump_oops; |
| int count; |
| int max_count; |
| } oops_cxt; |
| |
| static struct platform_device *dummy; |
| static struct ramoops_platform_data *dummy_data; |
| |
| static void ramoops_do_dump(struct kmsg_dumper *dumper, |
| enum kmsg_dump_reason reason, const char *s1, unsigned long l1, |
| const char *s2, unsigned long l2) |
| { |
| struct ramoops_context *cxt = container_of(dumper, |
| struct ramoops_context, dump); |
| unsigned long s1_start, s2_start; |
| unsigned long l1_cpy, l2_cpy; |
| int res, hdr_size; |
| char *buf, *buf_orig; |
| struct timeval timestamp; |
| |
| if (reason != KMSG_DUMP_OOPS && |
| reason != KMSG_DUMP_PANIC) |
| return; |
| |
| /* Only dump oopses if dump_oops is set */ |
| if (reason == KMSG_DUMP_OOPS && !cxt->dump_oops) |
| return; |
| |
| buf = cxt->virt_addr + (cxt->count * cxt->record_size); |
| buf_orig = buf; |
| |
| memset(buf, '\0', cxt->record_size); |
| res = sprintf(buf, "%s", RAMOOPS_KERNMSG_HDR); |
| buf += res; |
| do_gettimeofday(×tamp); |
| res = sprintf(buf, "%lu.%lu\n", (long)timestamp.tv_sec, (long)timestamp.tv_usec); |
| buf += res; |
| |
| hdr_size = buf - buf_orig; |
| l2_cpy = min(l2, cxt->record_size - hdr_size); |
| l1_cpy = min(l1, cxt->record_size - hdr_size - l2_cpy); |
| |
| s2_start = l2 - l2_cpy; |
| s1_start = l1 - l1_cpy; |
| |
| memcpy(buf, s1 + s1_start, l1_cpy); |
| memcpy(buf + l1_cpy, s2 + s2_start, l2_cpy); |
| |
| cxt->count = (cxt->count + 1) % cxt->max_count; |
| } |
| |
| static int __init ramoops_probe(struct platform_device *pdev) |
| { |
| struct ramoops_platform_data *pdata = pdev->dev.platform_data; |
| struct ramoops_context *cxt = &oops_cxt; |
| int err = -EINVAL; |
| |
| if (!pdata->mem_size || !pdata->record_size) { |
| pr_err("The memory size and the record size must be " |
| "non-zero\n"); |
| goto fail3; |
| } |
| |
| pdata->mem_size = rounddown_pow_of_two(pdata->mem_size); |
| pdata->record_size = rounddown_pow_of_two(pdata->record_size); |
| |
| /* Check for the minimum memory size */ |
| if (pdata->mem_size < MIN_MEM_SIZE && |
| pdata->record_size < MIN_MEM_SIZE) { |
| pr_err("memory size too small, minium is %lu\n", MIN_MEM_SIZE); |
| goto fail3; |
| } |
| |
| if (pdata->mem_size < pdata->record_size) { |
| pr_err("The memory size must be larger than the " |
| "records size\n"); |
| goto fail3; |
| } |
| |
| cxt->max_count = pdata->mem_size / pdata->record_size; |
| cxt->count = 0; |
| cxt->size = pdata->mem_size; |
| cxt->phys_addr = pdata->mem_address; |
| cxt->record_size = pdata->record_size; |
| cxt->dump_oops = pdata->dump_oops; |
| |
| if (!request_mem_region(cxt->phys_addr, cxt->size, "ramoops")) { |
| pr_err("request mem region failed\n"); |
| err = -EINVAL; |
| goto fail3; |
| } |
| |
| cxt->virt_addr = ioremap(cxt->phys_addr, cxt->size); |
| if (!cxt->virt_addr) { |
| pr_err("ioremap failed\n"); |
| goto fail2; |
| } |
| |
| cxt->dump.dump = ramoops_do_dump; |
| err = kmsg_dump_register(&cxt->dump); |
| if (err) { |
| pr_err("registering kmsg dumper failed\n"); |
| goto fail1; |
| } |
| |
| /* |
| * Update the module parameter variables as well so they are visible |
| * through /sys/module/ramoops/parameters/ |
| */ |
| mem_size = pdata->mem_size; |
| mem_address = pdata->mem_address; |
| record_size = pdata->record_size; |
| dump_oops = pdata->dump_oops; |
| |
| return 0; |
| |
| fail1: |
| iounmap(cxt->virt_addr); |
| fail2: |
| release_mem_region(cxt->phys_addr, cxt->size); |
| fail3: |
| return err; |
| } |
| |
| static int __exit ramoops_remove(struct platform_device *pdev) |
| { |
| struct ramoops_context *cxt = &oops_cxt; |
| |
| if (kmsg_dump_unregister(&cxt->dump) < 0) |
| pr_warn("could not unregister kmsg_dumper\n"); |
| |
| iounmap(cxt->virt_addr); |
| release_mem_region(cxt->phys_addr, cxt->size); |
| return 0; |
| } |
| |
| static struct platform_driver ramoops_driver = { |
| .remove = __exit_p(ramoops_remove), |
| .driver = { |
| .name = "ramoops", |
| .owner = THIS_MODULE, |
| }, |
| }; |
| |
| static int __init ramoops_init(void) |
| { |
| int ret; |
| ret = platform_driver_probe(&ramoops_driver, ramoops_probe); |
| if (ret == -ENODEV) { |
| /* |
| * If we didn't find a platform device, we use module parameters |
| * building platform data on the fly. |
| */ |
| pr_info("platform device not found, using module parameters\n"); |
| dummy_data = kzalloc(sizeof(struct ramoops_platform_data), |
| GFP_KERNEL); |
| if (!dummy_data) |
| return -ENOMEM; |
| dummy_data->mem_size = mem_size; |
| dummy_data->mem_address = mem_address; |
| dummy_data->record_size = record_size; |
| dummy_data->dump_oops = dump_oops; |
| dummy = platform_create_bundle(&ramoops_driver, ramoops_probe, |
| NULL, 0, dummy_data, |
| sizeof(struct ramoops_platform_data)); |
| |
| if (IS_ERR(dummy)) |
| ret = PTR_ERR(dummy); |
| else |
| ret = 0; |
| } |
| |
| return ret; |
| } |
| |
| static void __exit ramoops_exit(void) |
| { |
| platform_driver_unregister(&ramoops_driver); |
| kfree(dummy_data); |
| } |
| |
| module_init(ramoops_init); |
| module_exit(ramoops_exit); |
| |
| MODULE_LICENSE("GPL"); |
| MODULE_AUTHOR("Marco Stornelli <marco.stornelli@gmail.com>"); |
| MODULE_DESCRIPTION("RAM Oops/Panic logger/driver"); |