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Viewing changes to drivers/acpi/custom_method.c

  • Committer: Package Import Robot
  • Author(s): John Rigby, John Rigby
  • Date: 2011-09-26 10:44:23 UTC
  • Revision ID: package-import@ubuntu.com-20110926104423-3o58a3c1bj7x00rs
Tags: 3.0.0-1007.9
https://launchpad.net/bugs/826021
[ John Rigby ]

Enable crypto modules and remove crypto-modules from
exclude-module files
LP: #826021

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drivers/acpi/custom_method.c
 
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/*
 
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 * debugfs.c - ACPI debugfs interface to userspace.
 
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 */
 
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#include <linux/init.h>
 
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#include <linux/module.h>
 
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#include <linux/kernel.h>
 
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#include <linux/uaccess.h>
 
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#include <linux/debugfs.h>
 
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#include <acpi/acpi_drivers.h>
 
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#include "internal.h"
 
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#define _COMPONENT              ACPI_SYSTEM_COMPONENT
 
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ACPI_MODULE_NAME("custom_method");
 
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MODULE_LICENSE("GPL");
 
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static struct dentry *cm_dentry;
 
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/* /sys/kernel/debug/acpi/custom_method */
 
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static ssize_t cm_write(struct file *file, const char __user * user_buf,
 
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                        size_t count, loff_t *ppos)
 
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{
 
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        static char *buf;
 
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        static u32 max_size;
 
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        static u32 uncopied_bytes;
 
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        struct acpi_table_header table;
 
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        acpi_status status;
 
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        if (!(*ppos)) {
 
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                /* parse the table header to get the table length */
 
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                if (count <= sizeof(struct acpi_table_header))
 
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                        return -EINVAL;
 
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                if (copy_from_user(&table, user_buf,
 
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                                   sizeof(struct acpi_table_header)))
 
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                        return -EFAULT;
 
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                uncopied_bytes = max_size = table.length;
 
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                buf = kzalloc(max_size, GFP_KERNEL);
 
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                if (!buf)
 
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                        return -ENOMEM;
 
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        }
 
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        if (buf == NULL)
 
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                return -EINVAL;
 
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        if ((*ppos > max_size) ||
 
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            (*ppos + count > max_size) ||
 
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            (*ppos + count < count) ||
 
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            (count > uncopied_bytes))
 
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                return -EINVAL;
 
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        if (copy_from_user(buf + (*ppos), user_buf, count)) {
 
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                kfree(buf);
 
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                buf = NULL;
 
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                return -EFAULT;
 
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        }
 
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        uncopied_bytes -= count;
 
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        *ppos += count;
 
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        if (!uncopied_bytes) {
 
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                status = acpi_install_method(buf);
 
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                kfree(buf);
 
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                buf = NULL;
 
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                if (ACPI_FAILURE(status))
 
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                        return -EINVAL;
 
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                add_taint(TAINT_OVERRIDDEN_ACPI_TABLE);
 
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        }
 
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        return count;
 
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}
 
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static const struct file_operations cm_fops = {
 
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        .write = cm_write,
 
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        .llseek = default_llseek,
 
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};
 
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static int __init acpi_custom_method_init(void)
 
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{
 
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        if (acpi_debugfs_dir == NULL)
 
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                return -ENOENT;
 
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        cm_dentry = debugfs_create_file("custom_method", S_IWUSR,
 
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                                        acpi_debugfs_dir, NULL, &cm_fops);
 
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        if (cm_dentry == NULL)
 
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                return -ENODEV;
 
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        return 0;
 
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}
 
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static void __exit acpi_custom_method_exit(void)
 
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{
 
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        if (cm_dentry)
 
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                debugfs_remove(cm_dentry);
 
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 }
 
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module_init(acpi_custom_method_init);
 
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module_exit(acpi_custom_method_exit);