/* * Architecture specific sysfs attributes in /sys/kernel * * Copyright (C) 2007, Intel Corp. * Huang Ying * Copyright (C) 2013, 2013 Red Hat, Inc. * Dave Young * * This file is released under the GPLv2 */ #include #include #include #include #include #include #include #include #include static ssize_t version_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) { return sprintf(buf, "0x%04x\n", boot_params.hdr.version); } static struct kobj_attribute boot_params_version_attr = __ATTR_RO(version); static ssize_t boot_params_data_read(struct file *fp, struct kobject *kobj, struct bin_attribute *bin_attr, char *buf, loff_t off, size_t count) { memcpy(buf, (void *)&boot_params + off, count); return count; } static struct bin_attribute boot_params_data_attr = { .attr = { .name = "data", .mode = S_IRUGO, }, .read = boot_params_data_read, .size = sizeof(boot_params), }; static struct attribute *boot_params_version_attrs[] = { &boot_params_version_attr.attr, NULL, }; static struct bin_attribute *boot_params_data_attrs[] = { &boot_params_data_attr, NULL, }; static const struct attribute_group boot_params_attr_group = { .attrs = boot_params_version_attrs, .bin_attrs = boot_params_data_attrs, }; static int kobj_to_setup_data_nr(struct kobject *kobj, int *nr) { const char *name; name = kobject_name(kobj); return kstrtoint(name, 10, nr); } static int get_setup_data_paddr(int nr, u64 *paddr) { int i = 0; struct setup_data *data; u64 pa_data = boot_params.hdr.setup_data; while (pa_data) { if (nr == i) { *paddr = pa_data; return 0; } data = memremap(pa_data, sizeof(*data), MEMREMAP_WB); if (!data) return -ENOMEM; pa_data = data->next; memunmap(data); i++; } return -EINVAL; } static int __init get_setup_data_size(int nr, size_t *size) { int i = 0; struct setup_data *data; u64 pa_data = boot_params.hdr.setup_data; while (pa_data) { data = memremap(pa_data, sizeof(*data), MEMREMAP_WB); if (!data) return -ENOMEM; if (nr == i) { *size = data->len; memunmap(data); return 0; } pa_data = data->next; memunmap(data); i++; } return -EINVAL; } static ssize_t type_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) { int nr, ret; u64 paddr; struct setup_data *data; ret = kobj_to_setup_data_nr(kobj, &nr); if (ret) return ret; ret = get_setup_data_paddr(nr, &paddr); if (ret) return ret; data = memremap(paddr, sizeof(*data), MEMREMAP_WB); if (!data) return -ENOMEM; ret = sprintf(buf, "0x%x\n", data->type); memunmap(data); return ret; } static ssize_t setup_data_data_read(struct file *fp, struct kobject *kobj, struct bin_attribute *bin_attr, char *buf, loff_t off, size_t count) { int nr, ret = 0; u64 paddr; struct setup_data *data; void *p; ret = kobj_to_setup_data_nr(kobj, &nr); if (ret) return ret; ret = get_setup_data_paddr(nr, &paddr); if (ret) return ret; data = memremap(paddr, sizeof(*data), MEMREMAP_WB); if (!data) return -ENOMEM; if (off > data->len) { ret = -EINVAL; goto out; } if (count > data->len - off) count = data->len - off; if (!count) goto out; ret = count; p = memremap(paddr + sizeof(*data), data->len, MEMREMAP_WB); if (!p) { ret = -ENOMEM; goto out; } memcpy(buf, p + off, count); memunmap(p); out: memunmap(data); return ret; } static struct kobj_attribute type_attr = __ATTR_RO(type); static struct bin_attribute data_attr __ro_after_init = { .attr = { .name = "data", .mode = S_IRUGO, }, .read = setup_data_data_read, }; static struct attribute *setup_data_type_attrs[] = { &type_attr.attr, NULL, }; static struct bin_attribute *setup_data_data_attrs[] = { &data_attr, NULL, }; static const struct attribute_group setup_data_attr_group = { .attrs = setup_data_type_attrs, .bin_attrs = setup_data_data_attrs, }; static int __init create_setup_data_node(struct kobject *parent, struct kobject **kobjp, int nr) { int ret = 0; size_t size; struct kobject *kobj; char name[16]; /* should be enough for setup_data nodes numbers */ snprintf(name, 16, "%d", nr); kobj = kobject_create_and_add(name, parent); if (!kobj) return -ENOMEM; ret = get_setup_data_size(nr, &size); if (ret) goto out_kobj; data_attr.size = size; ret = sysfs_create_group(kobj, &setup_data_attr_group); if (ret) goto out_kobj; *kobjp = kobj; return 0; out_kobj: kobject_put(kobj); return ret; } static void __init cleanup_setup_data_node(struct kobject *kobj) { sysfs_remove_group(kobj, &setup_data_attr_group); kobject_put(kobj); } static int __init get_setup_data_total_num(u64 pa_data, int *nr) { int ret = 0; struct setup_data *data; *nr = 0; while (pa_data) { *nr += 1; data = memremap(pa_data, sizeof(*data), MEMREMAP_WB); if (!data) { ret = -ENOMEM; goto out; } pa_data = data->next; memunmap(data); } out: return ret; } static int __init create_setup_data_nodes(struct kobject *parent) { struct kobject *setup_data_kobj, **kobjp; u64 pa_data; int i, j, nr, ret = 0; pa_data = boot_params.hdr.setup_data; if (!pa_data) return 0; setup_data_kobj = kobject_create_and_add("setup_data", parent); if (!setup_data_kobj) { ret = -ENOMEM; goto out; } ret = get_setup_data_total_num(pa_data, &nr); if (ret) goto out_setup_data_kobj; kobjp = kmalloc(sizeof(*kobjp) * nr, GFP_KERNEL); if (!kobjp) { ret = -ENOMEM; goto out_setup_data_kobj; } for (i = 0; i < nr; i++) { ret = create_setup_data_node(setup_data_kobj, kobjp + i, i); if (ret) goto out_clean_nodes; } kfree(kobjp); return 0; out_clean_nodes: for (j = i - 1; j >= 0; j--) cleanup_setup_data_node(*(kobjp + j)); kfree(kobjp); out_setup_data_kobj: kobject_put(setup_data_kobj); out: return ret; } static int __init boot_params_ksysfs_init(void) { int ret; struct kobject *boot_params_kobj; boot_params_kobj = kobject_create_and_add("boot_params", kernel_kobj); if (!boot_params_kobj) { ret = -ENOMEM; goto out; } ret = sysfs_create_group(boot_params_kobj, &boot_params_attr_group); if (ret) goto out_boot_params_kobj; ret = create_setup_data_nodes(boot_params_kobj); if (ret) goto out_create_group; return 0; out_create_group: sysfs_remove_group(boot_params_kobj, &boot_params_attr_group); out_boot_params_kobj: kobject_put(boot_params_kobj); out: return ret; } arch_initcall(boot_params_ksysfs_init);