1 // SPDX-License-Identifier: MIT 2 /* 3 * Copyright © 2019 Intel Corporation 4 */ 5 6 #include <linux/kernel.h> 7 8 #include "i915_debugfs_params.h" 9 #include "i915_drv.h" 10 #include "i915_params.h" 11 12 /* int param */ 13 static int i915_param_int_show(struct seq_file *m, void *data) 14 { 15 int *value = m->private; 16 17 seq_printf(m, "%d\n", *value); 18 19 return 0; 20 } 21 22 static int i915_param_int_open(struct inode *inode, struct file *file) 23 { 24 return single_open(file, i915_param_int_show, inode->i_private); 25 } 26 27 static ssize_t i915_param_int_write(struct file *file, 28 const char __user *ubuf, size_t len, 29 loff_t *offp) 30 { 31 struct seq_file *m = file->private_data; 32 int *value = m->private; 33 int ret; 34 35 ret = kstrtoint_from_user(ubuf, len, 0, value); 36 if (ret) { 37 /* support boolean values too */ 38 bool b; 39 40 ret = kstrtobool_from_user(ubuf, len, &b); 41 if (!ret) 42 *value = b; 43 } 44 45 return ret ?: len; 46 } 47 48 static const struct file_operations i915_param_int_fops = { 49 .owner = THIS_MODULE, 50 .open = i915_param_int_open, 51 .read = seq_read, 52 .write = i915_param_int_write, 53 .llseek = default_llseek, 54 .release = single_release, 55 }; 56 57 static const struct file_operations i915_param_int_fops_ro = { 58 .owner = THIS_MODULE, 59 .open = i915_param_int_open, 60 .read = seq_read, 61 .llseek = default_llseek, 62 .release = single_release, 63 }; 64 65 /* unsigned int param */ 66 static int i915_param_uint_show(struct seq_file *m, void *data) 67 { 68 unsigned int *value = m->private; 69 70 seq_printf(m, "%u\n", *value); 71 72 return 0; 73 } 74 75 static int i915_param_uint_open(struct inode *inode, struct file *file) 76 { 77 return single_open(file, i915_param_uint_show, inode->i_private); 78 } 79 80 static ssize_t i915_param_uint_write(struct file *file, 81 const char __user *ubuf, size_t len, 82 loff_t *offp) 83 { 84 struct seq_file *m = file->private_data; 85 unsigned int *value = m->private; 86 int ret; 87 88 ret = kstrtouint_from_user(ubuf, len, 0, value); 89 if (ret) { 90 /* support boolean values too */ 91 bool b; 92 93 ret = kstrtobool_from_user(ubuf, len, &b); 94 if (!ret) 95 *value = b; 96 } 97 98 return ret ?: len; 99 } 100 101 static const struct file_operations i915_param_uint_fops = { 102 .owner = THIS_MODULE, 103 .open = i915_param_uint_open, 104 .read = seq_read, 105 .write = i915_param_uint_write, 106 .llseek = default_llseek, 107 .release = single_release, 108 }; 109 110 static const struct file_operations i915_param_uint_fops_ro = { 111 .owner = THIS_MODULE, 112 .open = i915_param_uint_open, 113 .read = seq_read, 114 .llseek = default_llseek, 115 .release = single_release, 116 }; 117 118 /* char * param */ 119 static int i915_param_charp_show(struct seq_file *m, void *data) 120 { 121 const char **s = m->private; 122 123 seq_printf(m, "%s\n", *s); 124 125 return 0; 126 } 127 128 static int i915_param_charp_open(struct inode *inode, struct file *file) 129 { 130 return single_open(file, i915_param_charp_show, inode->i_private); 131 } 132 133 static ssize_t i915_param_charp_write(struct file *file, 134 const char __user *ubuf, size_t len, 135 loff_t *offp) 136 { 137 struct seq_file *m = file->private_data; 138 char **s = m->private; 139 char *new, *old; 140 141 old = *s; 142 new = strndup_user(ubuf, PAGE_SIZE); 143 if (IS_ERR(new)) { 144 len = PTR_ERR(new); 145 goto out; 146 } 147 148 *s = new; 149 150 kfree(old); 151 out: 152 return len; 153 } 154 155 static const struct file_operations i915_param_charp_fops = { 156 .owner = THIS_MODULE, 157 .open = i915_param_charp_open, 158 .read = seq_read, 159 .write = i915_param_charp_write, 160 .llseek = default_llseek, 161 .release = single_release, 162 }; 163 164 static const struct file_operations i915_param_charp_fops_ro = { 165 .owner = THIS_MODULE, 166 .open = i915_param_charp_open, 167 .read = seq_read, 168 .llseek = default_llseek, 169 .release = single_release, 170 }; 171 172 #define RO(mode) (((mode) & 0222) == 0) 173 174 static struct dentry * 175 i915_debugfs_create_int(const char *name, umode_t mode, 176 struct dentry *parent, int *value) 177 { 178 return debugfs_create_file_unsafe(name, mode, parent, value, 179 RO(mode) ? &i915_param_int_fops_ro : 180 &i915_param_int_fops); 181 } 182 183 static struct dentry * 184 i915_debugfs_create_uint(const char *name, umode_t mode, 185 struct dentry *parent, unsigned int *value) 186 { 187 return debugfs_create_file_unsafe(name, mode, parent, value, 188 RO(mode) ? &i915_param_uint_fops_ro : 189 &i915_param_uint_fops); 190 } 191 192 static struct dentry * 193 i915_debugfs_create_charp(const char *name, umode_t mode, 194 struct dentry *parent, char **value) 195 { 196 return debugfs_create_file(name, mode, parent, value, 197 RO(mode) ? &i915_param_charp_fops_ro : 198 &i915_param_charp_fops); 199 } 200 201 static __always_inline void 202 _i915_param_create_file(struct dentry *parent, const char *name, 203 const char *type, int mode, void *value) 204 { 205 if (!mode) 206 return; 207 208 if (!__builtin_strcmp(type, "bool")) 209 debugfs_create_bool(name, mode, parent, value); 210 else if (!__builtin_strcmp(type, "int")) 211 i915_debugfs_create_int(name, mode, parent, value); 212 else if (!__builtin_strcmp(type, "unsigned int")) 213 i915_debugfs_create_uint(name, mode, parent, value); 214 else if (!__builtin_strcmp(type, "unsigned long")) 215 debugfs_create_ulong(name, mode, parent, value); 216 else if (!__builtin_strcmp(type, "char *")) 217 i915_debugfs_create_charp(name, mode, parent, value); 218 else 219 WARN(1, "no debugfs fops defined for param type %s (i915.%s)\n", 220 type, name); 221 } 222 223 /* add a subdirectory with files for each i915 param */ 224 struct dentry *i915_debugfs_params(struct drm_i915_private *i915) 225 { 226 struct drm_minor *minor = i915->drm.primary; 227 struct i915_params *params = &i915->params; 228 struct dentry *dir; 229 230 dir = debugfs_create_dir("i915_params", minor->debugfs_root); 231 if (IS_ERR(dir)) 232 return dir; 233 234 /* 235 * Note: We could create files for params needing special handling 236 * here. Set mode in params to 0 to skip the generic create file, or 237 * just let the generic create file fail silently with -EEXIST. 238 */ 239 240 #define REGISTER(T, x, unused, mode, ...) _i915_param_create_file(dir, #x, #T, mode, ¶ms->x); 241 I915_PARAMS_FOR_EACH(REGISTER); 242 #undef REGISTER 243 244 return dir; 245 } 246