// SPDX-License-Identifier: GPL-2.0-only /* * Architecture specific debugfs files * * Copyright (C) 2007, Intel Corp. * Huang Ying <ying.huang@intel.com> */ #include <linux/debugfs.h> #include <linux/uaccess.h> #include <linux/export.h> #include <linux/slab.h> #include <linux/init.h> #include <linux/stat.h> #include <linux/io.h> #include <linux/mm.h> #include <asm/setup.h> struct dentry *arch_debugfs_dir; EXPORT_SYMBOL(arch_debugfs_dir); #ifdef CONFIG_DEBUG_BOOT_PARAMS struct setup_data_node { u64 paddr; u32 type; u32 len; }; static ssize_t setup_data_read(struct file *file, char __user *user_buf, size_t count, loff_t *ppos) { struct setup_data_node *node = file->private_data; unsigned long remain; loff_t pos = *ppos; void *p; u64 pa; if (pos < 0) return -EINVAL; if (pos >= node->len) return 0; if (count > node->len - pos) count = node->len - pos; pa = node->paddr + pos; /* Is it direct data or invalid indirect one? */ if (!(node->type & SETUP_INDIRECT) || node->type == SETUP_INDIRECT) pa += sizeof(struct setup_data); p = memremap(pa, count, MEMREMAP_WB); if (!p) return -ENOMEM; remain = copy_to_user(user_buf, p, count); memunmap(p); if (remain) return -EFAULT; *ppos = pos + count; return count; } static const struct file_operations fops_setup_data = { .read = setup_data_read, .open = simple_open, .llseek = default_llseek, }; static void __init create_setup_data_node(struct dentry *parent, int no, struct setup_data_node *node) { struct dentry *d; char buf[16]; sprintf(buf, "%d", no); d = debugfs_create_dir(buf, parent); debugfs_create_x32("type", S_IRUGO, d, &node->type); debugfs_create_file("data", S_IRUGO, d, node, &fops_setup_data); } static int __init create_setup_data_nodes(struct dentry *parent) { struct setup_indirect *indirect; struct setup_data_node *node; struct setup_data *data; u64 pa_data, pa_next; struct dentry *d; int error; u32 len; int no = 0; d = debugfs_create_dir("setup_data", parent); pa_data = boot_params.hdr.setup_data; while (pa_data) { node = kmalloc(sizeof(*node), GFP_KERNEL); if (!node) { error = -ENOMEM; goto err_dir; } data = memremap(pa_data, sizeof(*data), MEMREMAP_WB); if (!data) { kfree(node); error = -ENOMEM; goto err_dir; } pa_next = data->next; if (data->type == SETUP_INDIRECT) { len = sizeof(*data) + data->len; memunmap(data); data = memremap(pa_data, len, MEMREMAP_WB); if (!data) { kfree(node); error = -ENOMEM; goto err_dir; } indirect = (struct setup_indirect *)data->data; if (indirect->type != SETUP_INDIRECT) { node->paddr = indirect->addr; node->type = indirect->type; node->len = indirect->len; } else { node->paddr = pa_data; node->type = data->type; node->len = data->len; } } else { node->paddr = pa_data; node->type = data->type; node->len = data->len; } create_setup_data_node(d, no, node); pa_data = pa_next; memunmap(data); no++; } return 0; err_dir: debugfs_remove_recursive(d); return error; } static struct debugfs_blob_wrapper boot_params_blob = { .data = &boot_params, .size = sizeof(boot_params), }; static int __init boot_params_kdebugfs_init(void) { struct dentry *dbp; int error; dbp = debugfs_create_dir("boot_params", arch_debugfs_dir); debugfs_create_x16("version", S_IRUGO, dbp, &boot_params.hdr.version); debugfs_create_blob("data", S_IRUGO, dbp, &boot_params_blob); error = create_setup_data_nodes(dbp); if (error) debugfs_remove_recursive(dbp); return error; } #endif /* CONFIG_DEBUG_BOOT_PARAMS */ static int __init arch_kdebugfs_init(void) { int error = 0; arch_debugfs_dir = debugfs_create_dir("x86", NULL); #ifdef CONFIG_DEBUG_BOOT_PARAMS error = boot_params_kdebugfs_init(); #endif return error; } arch_initcall
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