git://bbs.cooldavid.org / net-next-2.6.git / blame
| Commit | Line | Data |
|---|---|---|
| a25ee920 ZR |
1 | /* |
| 2 | * debugfs.c - ACPI debugfs interface to userspace. | |
| 3 | */ | |
| 4 | ||
| 5 | #include <linux/init.h> | |
| 6 | #include <linux/module.h> | |
| 7 | #include <linux/kernel.h> | |
| 8 | #include <linux/uaccess.h> | |
| 9 | #include <linux/debugfs.h> | |
| 10 | #include <acpi/acpi_drivers.h> | |
| 11 | ||
| 12 | #define _COMPONENT ACPI_SYSTEM_COMPONENT | |
| 13 | ACPI_MODULE_NAME("debugfs"); | |
| 14 | ||
| c637e486 ZR |
15 | |
| 16 | /* /sys/modules/acpi/parameters/aml_debug_output */ | |
| 17 | ||
| 18 | module_param_named(aml_debug_output, acpi_gbl_enable_aml_debug_object, | |
| 19 | bool, 0644); | |
| 20 | MODULE_PARM_DESC(aml_debug_output, | |
| 21 | "To enable/disable the ACPI Debug Object output."); | |
| 22 | ||
| a25ee920 ZR |
23 | /* /sys/kernel/debug/acpi/custom_method */ |
| 24 | ||
| 25 | static ssize_t cm_write(struct file *file, const char __user * user_buf, | |
| 26 | size_t count, loff_t *ppos) | |
| 27 | { | |
| 28 | static char *buf; | |
| 29 | static int uncopied_bytes; | |
| 30 | struct acpi_table_header table; | |
| 31 | acpi_status status; | |
| 32 | ||
| 33 | if (!(*ppos)) { | |
| 34 | /* parse the table header to get the table length */ | |
| 35 | if (count <= sizeof(struct acpi_table_header)) | |
| 36 | return -EINVAL; | |
| 37 | if (copy_from_user(&table, user_buf, | |
| 38 | sizeof(struct acpi_table_header))) | |
| 39 | return -EFAULT; | |
| 40 | uncopied_bytes = table.length; | |
| 41 | buf = kzalloc(uncopied_bytes, GFP_KERNEL); | |
| 42 | if (!buf) | |
| 43 | return -ENOMEM; | |
| 44 | } | |
| 45 | ||
| 46 | if (uncopied_bytes < count) { | |
| 47 | kfree(buf); | |
| 48 | return -EINVAL; | |
| 49 | } | |
| 50 | ||
| 51 | if (copy_from_user(buf + (*ppos), user_buf, count)) { | |
| 52 | kfree(buf); | |
| 53 | return -EFAULT; | |
| 54 | } | |
| 55 | ||
| 56 | uncopied_bytes -= count; | |
| 57 | *ppos += count; | |
| 58 | ||
| 59 | if (!uncopied_bytes) { | |
| 60 | status = acpi_install_method(buf); | |
| 61 | kfree(buf); | |
| 62 | if (ACPI_FAILURE(status)) | |
| 63 | return -EINVAL; | |
| 64 | add_taint(TAINT_OVERRIDDEN_ACPI_TABLE); | |
| 65 | } | |
| 66 | ||
| 67 | return count; | |
| 68 | } | |
| 69 | ||
| 70 | static const struct file_operations cm_fops = { | |
| 71 | .write = cm_write, | |
| 6038f373 | 72 | .llseek = default_llseek, |
| a25ee920 ZR |
73 | }; |
| 74 | ||
| 75 | int __init acpi_debugfs_init(void) | |
| 76 | { | |
| 77 | struct dentry *acpi_dir, *cm_dentry; | |
| 78 | ||
| 79 | acpi_dir = debugfs_create_dir("acpi", NULL); | |
| 80 | if (!acpi_dir) | |
| 81 | goto err; | |
| 82 | ||
| 83 | cm_dentry = debugfs_create_file("custom_method", S_IWUGO, | |
| 84 | acpi_dir, NULL, &cm_fops); | |
| 85 | if (!cm_dentry) | |
| 86 | goto err; | |
| 87 | ||
| 88 | return 0; | |
| 89 | ||
| 90 | err: | |
| 91 | if (acpi_dir) | |
| 92 | debugfs_remove(acpi_dir); | |
| 93 | return -EINVAL; | |
| 94 | } |