Author | Tokens | Token Proportion | Commits | Commit Proportion |
---|---|---|---|---|
Stewart Smith | 1485 | 85.44% | 3 | 12.50% |
Vasant Hegde | 65 | 3.74% | 6 | 25.00% |
Alistair Popple | 56 | 3.22% | 1 | 4.17% |
Anton Blanchard | 50 | 2.88% | 2 | 8.33% |
Benjamin Herrenschmidt | 33 | 1.90% | 3 | 12.50% |
Mukesh Ojha | 26 | 1.50% | 3 | 12.50% |
Michael Neuling | 9 | 0.52% | 1 | 4.17% |
Greg Kroah-Hartman | 7 | 0.40% | 1 | 4.17% |
Mahesh Salgaonkar | 2 | 0.12% | 1 | 4.17% |
Thomas Gleixner | 2 | 0.12% | 1 | 4.17% |
Russell Currey | 2 | 0.12% | 1 | 4.17% |
Rohan McLure | 1 | 0.06% | 1 | 4.17% |
Total | 1738 | 24 |
// 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 const 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, }; ATTRIBUTE_GROUPS(dump_default); static struct kobj_type dump_ktype = { .sysfs_ops = &dump_sysfs_ops, .release = &dump_release, .default_groups = dump_default_groups, }; 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; /* Dump 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(); }
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