forked from Qortal/Brooklyn
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
458 lines
10 KiB
458 lines
10 KiB
// SPDX-License-Identifier: GPL-2.0-or-later |
|
/* |
|
* PowerNV OPAL Dump Interface |
|
* |
|
* Copyright 2013,2014 IBM Corp. |
|
*/ |
|
|
|
#include <linux/kobject.h> |
|
#include <linux/mm.h> |
|
#include <linux/slab.h> |
|
#include <linux/vmalloc.h> |
|
#include <linux/pagemap.h> |
|
#include <linux/delay.h> |
|
#include <linux/interrupt.h> |
|
|
|
#include <asm/opal.h> |
|
|
|
#define DUMP_TYPE_FSP 0x01 |
|
|
|
struct dump_obj { |
|
struct kobject kobj; |
|
struct bin_attribute dump_attr; |
|
uint32_t id; /* becomes object name */ |
|
uint32_t type; |
|
uint32_t size; |
|
char *buffer; |
|
}; |
|
#define to_dump_obj(x) container_of(x, struct dump_obj, kobj) |
|
|
|
struct dump_attribute { |
|
struct attribute attr; |
|
ssize_t (*show)(struct dump_obj *dump, struct dump_attribute *attr, |
|
char *buf); |
|
ssize_t (*store)(struct dump_obj *dump, struct dump_attribute *attr, |
|
const char *buf, size_t count); |
|
}; |
|
#define to_dump_attr(x) container_of(x, struct dump_attribute, attr) |
|
|
|
static ssize_t dump_id_show(struct dump_obj *dump_obj, |
|
struct dump_attribute *attr, |
|
char *buf) |
|
{ |
|
return sprintf(buf, "0x%x\n", dump_obj->id); |
|
} |
|
|
|
static const char* dump_type_to_string(uint32_t type) |
|
{ |
|
switch (type) { |
|
case 0x01: return "SP Dump"; |
|
case 0x02: return "System/Platform Dump"; |
|
case 0x03: return "SMA Dump"; |
|
default: return "unknown"; |
|
} |
|
} |
|
|
|
static ssize_t dump_type_show(struct dump_obj *dump_obj, |
|
struct dump_attribute *attr, |
|
char *buf) |
|
{ |
|
|
|
return sprintf(buf, "0x%x %s\n", dump_obj->type, |
|
dump_type_to_string(dump_obj->type)); |
|
} |
|
|
|
static ssize_t dump_ack_show(struct dump_obj *dump_obj, |
|
struct dump_attribute *attr, |
|
char *buf) |
|
{ |
|
return sprintf(buf, "ack - acknowledge dump\n"); |
|
} |
|
|
|
/* |
|
* Send acknowledgement to OPAL |
|
*/ |
|
static int64_t dump_send_ack(uint32_t dump_id) |
|
{ |
|
int rc; |
|
|
|
rc = opal_dump_ack(dump_id); |
|
if (rc) |
|
pr_warn("%s: Failed to send ack to Dump ID 0x%x (%d)\n", |
|
__func__, dump_id, rc); |
|
return rc; |
|
} |
|
|
|
static ssize_t dump_ack_store(struct dump_obj *dump_obj, |
|
struct dump_attribute *attr, |
|
const char *buf, |
|
size_t count) |
|
{ |
|
/* |
|
* Try to self remove this attribute. If we are successful, |
|
* delete the kobject itself. |
|
*/ |
|
if (sysfs_remove_file_self(&dump_obj->kobj, &attr->attr)) { |
|
dump_send_ack(dump_obj->id); |
|
kobject_put(&dump_obj->kobj); |
|
} |
|
return count; |
|
} |
|
|
|
/* Attributes of a dump |
|
* The binary attribute of the dump itself is dynamic |
|
* due to the dynamic size of the dump |
|
*/ |
|
static struct dump_attribute id_attribute = |
|
__ATTR(id, 0444, dump_id_show, NULL); |
|
static struct dump_attribute type_attribute = |
|
__ATTR(type, 0444, dump_type_show, NULL); |
|
static struct dump_attribute ack_attribute = |
|
__ATTR(acknowledge, 0660, dump_ack_show, dump_ack_store); |
|
|
|
static ssize_t init_dump_show(struct dump_obj *dump_obj, |
|
struct dump_attribute *attr, |
|
char *buf) |
|
{ |
|
return sprintf(buf, "1 - initiate Service Processor(FSP) dump\n"); |
|
} |
|
|
|
static int64_t dump_fips_init(uint8_t type) |
|
{ |
|
int rc; |
|
|
|
rc = opal_dump_init(type); |
|
if (rc) |
|
pr_warn("%s: Failed to initiate FSP dump (%d)\n", |
|
__func__, rc); |
|
return rc; |
|
} |
|
|
|
static ssize_t init_dump_store(struct dump_obj *dump_obj, |
|
struct dump_attribute *attr, |
|
const char *buf, |
|
size_t count) |
|
{ |
|
int rc; |
|
|
|
rc = dump_fips_init(DUMP_TYPE_FSP); |
|
if (rc == OPAL_SUCCESS) |
|
pr_info("%s: Initiated FSP dump\n", __func__); |
|
|
|
return count; |
|
} |
|
|
|
static struct dump_attribute initiate_attribute = |
|
__ATTR(initiate_dump, 0600, init_dump_show, init_dump_store); |
|
|
|
static struct attribute *initiate_attrs[] = { |
|
&initiate_attribute.attr, |
|
NULL, |
|
}; |
|
|
|
static struct attribute_group initiate_attr_group = { |
|
.attrs = initiate_attrs, |
|
}; |
|
|
|
static struct kset *dump_kset; |
|
|
|
static ssize_t dump_attr_show(struct kobject *kobj, |
|
struct attribute *attr, |
|
char *buf) |
|
{ |
|
struct dump_attribute *attribute; |
|
struct dump_obj *dump; |
|
|
|
attribute = to_dump_attr(attr); |
|
dump = to_dump_obj(kobj); |
|
|
|
if (!attribute->show) |
|
return -EIO; |
|
|
|
return attribute->show(dump, attribute, buf); |
|
} |
|
|
|
static ssize_t dump_attr_store(struct kobject *kobj, |
|
struct attribute *attr, |
|
const char *buf, size_t len) |
|
{ |
|
struct dump_attribute *attribute; |
|
struct dump_obj *dump; |
|
|
|
attribute = to_dump_attr(attr); |
|
dump = to_dump_obj(kobj); |
|
|
|
if (!attribute->store) |
|
return -EIO; |
|
|
|
return attribute->store(dump, attribute, buf, len); |
|
} |
|
|
|
static const struct sysfs_ops dump_sysfs_ops = { |
|
.show = dump_attr_show, |
|
.store = dump_attr_store, |
|
}; |
|
|
|
static void dump_release(struct kobject *kobj) |
|
{ |
|
struct dump_obj *dump; |
|
|
|
dump = to_dump_obj(kobj); |
|
vfree(dump->buffer); |
|
kfree(dump); |
|
} |
|
|
|
static struct attribute *dump_default_attrs[] = { |
|
&id_attribute.attr, |
|
&type_attribute.attr, |
|
&ack_attribute.attr, |
|
NULL, |
|
}; |
|
|
|
static struct kobj_type dump_ktype = { |
|
.sysfs_ops = &dump_sysfs_ops, |
|
.release = &dump_release, |
|
.default_attrs = dump_default_attrs, |
|
}; |
|
|
|
static int64_t dump_read_info(uint32_t *dump_id, uint32_t *dump_size, uint32_t *dump_type) |
|
{ |
|
__be32 id, size, type; |
|
int rc; |
|
|
|
type = cpu_to_be32(0xffffffff); |
|
|
|
rc = opal_dump_info2(&id, &size, &type); |
|
if (rc == OPAL_PARAMETER) |
|
rc = opal_dump_info(&id, &size); |
|
|
|
if (rc) { |
|
pr_warn("%s: Failed to get dump info (%d)\n", |
|
__func__, rc); |
|
return rc; |
|
} |
|
|
|
*dump_id = be32_to_cpu(id); |
|
*dump_size = be32_to_cpu(size); |
|
*dump_type = be32_to_cpu(type); |
|
|
|
return rc; |
|
} |
|
|
|
static int64_t dump_read_data(struct dump_obj *dump) |
|
{ |
|
struct opal_sg_list *list; |
|
uint64_t addr; |
|
int64_t rc; |
|
|
|
/* Allocate memory */ |
|
dump->buffer = vzalloc(PAGE_ALIGN(dump->size)); |
|
if (!dump->buffer) { |
|
pr_err("%s : Failed to allocate memory\n", __func__); |
|
rc = -ENOMEM; |
|
goto out; |
|
} |
|
|
|
/* Generate SG list */ |
|
list = opal_vmalloc_to_sg_list(dump->buffer, dump->size); |
|
if (!list) { |
|
rc = -ENOMEM; |
|
goto out; |
|
} |
|
|
|
/* First entry address */ |
|
addr = __pa(list); |
|
|
|
/* Fetch data */ |
|
rc = OPAL_BUSY_EVENT; |
|
while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) { |
|
rc = opal_dump_read(dump->id, addr); |
|
if (rc == OPAL_BUSY_EVENT) { |
|
opal_poll_events(NULL); |
|
msleep(20); |
|
} |
|
} |
|
|
|
if (rc != OPAL_SUCCESS && rc != OPAL_PARTIAL) |
|
pr_warn("%s: Extract dump failed for ID 0x%x\n", |
|
__func__, dump->id); |
|
|
|
/* Free SG list */ |
|
opal_free_sg_list(list); |
|
|
|
out: |
|
return rc; |
|
} |
|
|
|
static ssize_t dump_attr_read(struct file *filep, struct kobject *kobj, |
|
struct bin_attribute *bin_attr, |
|
char *buffer, loff_t pos, size_t count) |
|
{ |
|
ssize_t rc; |
|
|
|
struct dump_obj *dump = to_dump_obj(kobj); |
|
|
|
if (!dump->buffer) { |
|
rc = dump_read_data(dump); |
|
|
|
if (rc != OPAL_SUCCESS && rc != OPAL_PARTIAL) { |
|
vfree(dump->buffer); |
|
dump->buffer = NULL; |
|
|
|
return -EIO; |
|
} |
|
if (rc == OPAL_PARTIAL) { |
|
/* On a partial read, we just return EIO |
|
* and rely on userspace to ask us to try |
|
* again. |
|
*/ |
|
pr_info("%s: Platform dump partially read. ID = 0x%x\n", |
|
__func__, dump->id); |
|
return -EIO; |
|
} |
|
} |
|
|
|
memcpy(buffer, dump->buffer + pos, count); |
|
|
|
/* You may think we could free the dump buffer now and retrieve |
|
* it again later if needed, but due to current firmware limitation, |
|
* that's not the case. So, once read into userspace once, |
|
* we keep the dump around until it's acknowledged by userspace. |
|
*/ |
|
|
|
return count; |
|
} |
|
|
|
static void create_dump_obj(uint32_t id, size_t size, uint32_t type) |
|
{ |
|
struct dump_obj *dump; |
|
int rc; |
|
|
|
dump = kzalloc(sizeof(*dump), GFP_KERNEL); |
|
if (!dump) |
|
return; |
|
|
|
dump->kobj.kset = dump_kset; |
|
|
|
kobject_init(&dump->kobj, &dump_ktype); |
|
|
|
sysfs_bin_attr_init(&dump->dump_attr); |
|
|
|
dump->dump_attr.attr.name = "dump"; |
|
dump->dump_attr.attr.mode = 0400; |
|
dump->dump_attr.size = size; |
|
dump->dump_attr.read = dump_attr_read; |
|
|
|
dump->id = id; |
|
dump->size = size; |
|
dump->type = type; |
|
|
|
rc = kobject_add(&dump->kobj, NULL, "0x%x-0x%x", type, id); |
|
if (rc) { |
|
kobject_put(&dump->kobj); |
|
return; |
|
} |
|
|
|
/* |
|
* As soon as the sysfs file for this dump is created/activated there is |
|
* a chance the opal_errd daemon (or any userspace) might read and |
|
* acknowledge the dump before kobject_uevent() is called. If that |
|
* happens then there is a potential race between |
|
* dump_ack_store->kobject_put() and kobject_uevent() which leads to a |
|
* use-after-free of a kernfs object resulting in a kernel crash. |
|
* |
|
* To avoid that, we need to take a reference on behalf of the bin file, |
|
* so that our reference remains valid while we call kobject_uevent(). |
|
* We then drop our reference before exiting the function, leaving the |
|
* bin file to drop the last reference (if it hasn't already). |
|
*/ |
|
|
|
/* Take a reference for the bin file */ |
|
kobject_get(&dump->kobj); |
|
rc = sysfs_create_bin_file(&dump->kobj, &dump->dump_attr); |
|
if (rc == 0) { |
|
kobject_uevent(&dump->kobj, KOBJ_ADD); |
|
|
|
pr_info("%s: New platform dump. ID = 0x%x Size %u\n", |
|
__func__, dump->id, dump->size); |
|
} else { |
|
/* Drop reference count taken for bin file */ |
|
kobject_put(&dump->kobj); |
|
} |
|
|
|
/* Drop our reference */ |
|
kobject_put(&dump->kobj); |
|
return; |
|
} |
|
|
|
static irqreturn_t process_dump(int irq, void *data) |
|
{ |
|
int rc; |
|
uint32_t dump_id, dump_size, dump_type; |
|
char name[22]; |
|
struct kobject *kobj; |
|
|
|
rc = dump_read_info(&dump_id, &dump_size, &dump_type); |
|
if (rc != OPAL_SUCCESS) |
|
return IRQ_HANDLED; |
|
|
|
sprintf(name, "0x%x-0x%x", dump_type, dump_id); |
|
|
|
/* we may get notified twice, let's handle |
|
* that gracefully and not create two conflicting |
|
* entries. |
|
*/ |
|
kobj = kset_find_obj(dump_kset, name); |
|
if (kobj) { |
|
/* Drop reference added by kset_find_obj() */ |
|
kobject_put(kobj); |
|
return IRQ_HANDLED; |
|
} |
|
|
|
create_dump_obj(dump_id, dump_size, dump_type); |
|
|
|
return IRQ_HANDLED; |
|
} |
|
|
|
void __init opal_platform_dump_init(void) |
|
{ |
|
int rc; |
|
int dump_irq; |
|
|
|
/* ELOG not supported by firmware */ |
|
if (!opal_check_token(OPAL_DUMP_READ)) |
|
return; |
|
|
|
dump_kset = kset_create_and_add("dump", NULL, opal_kobj); |
|
if (!dump_kset) { |
|
pr_warn("%s: Failed to create dump kset\n", __func__); |
|
return; |
|
} |
|
|
|
rc = sysfs_create_group(&dump_kset->kobj, &initiate_attr_group); |
|
if (rc) { |
|
pr_warn("%s: Failed to create initiate dump attr group\n", |
|
__func__); |
|
kobject_put(&dump_kset->kobj); |
|
return; |
|
} |
|
|
|
dump_irq = opal_event_request(ilog2(OPAL_EVENT_DUMP_AVAIL)); |
|
if (!dump_irq) { |
|
pr_err("%s: Can't register OPAL event irq (%d)\n", |
|
__func__, dump_irq); |
|
return; |
|
} |
|
|
|
rc = request_threaded_irq(dump_irq, NULL, process_dump, |
|
IRQF_TRIGGER_HIGH | IRQF_ONESHOT, |
|
"opal-dump", NULL); |
|
if (rc) { |
|
pr_err("%s: Can't request OPAL event irq (%d)\n", |
|
__func__, rc); |
|
return; |
|
} |
|
|
|
if (opal_check_token(OPAL_DUMP_RESEND)) |
|
opal_dump_resend_notification(); |
|
}
|
|
|