Re: [PATCH 6/8] eventfs: adding eventfs lookup, read, open functions

kernel test robot
2023-01-22T19:38:47Z

Hi Ajay,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on linus/master]
[also build test WARNING on v6.2-rc5 next-20230120]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url: https://github.com/intel-lab-lkp/linux/commits/Ajay-Kaher/eventfs-adding-eventfs-dir-add-functions/20230123-010956
patch link: https://lore.kernel.org/r/1674407228-49109-6-git-send-email-akaher%40vmware.com
patch subject: [PATCH 6/8] eventfs: adding eventfs lookup, read, open functions
config: arc-defconfig (https://download.01.org/0day-ci/archive/20230123/202301230340.oZWnhDJu-lkp@intel.com/config)
compiler: arc-elf-gcc (GCC) 12.1.0
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# https://github.com/intel-lab-lkp/linux/commit/bdfb24dc39f183eda75dc7c6ad54798181ad4a94
git remote add linux-review https://github.com/intel-lab-lkp/linux
git fetch --no-tags linux-review Ajay-Kaher/eventfs-adding-eventfs-dir-add-functions/20230123-010956
git checkout bdfb24dc39f183eda75dc7c6ad54798181ad4a94
# save the config file
mkdir build_dir && cp config build_dir/.config
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=arc olddefconfig
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=arc SHELL=/bin/bash fs/tracefs/ kernel/trace/

If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <lkp@intel.com>

All warnings (new ones prefixed by >>):

fs/tracefs/event_inode.c:48:16: warning: no previous prototype for 'eventfs_create_file' [-Wmissing-prototypes]
48 | struct dentry *eventfs_create_file(const char *name, umode_t mode,
| ^~~~~~~~~~~~~~~~~~~
fs/tracefs/event_inode.c:117:16: warning: no previous prototype for 'eventfs_create_dir' [-Wmissing-prototypes]
117 | struct dentry *eventfs_create_dir(const char *name, umode_t mode,
| ^~~~~~~~~~~~~~~~~~
>> fs/tracefs/event_inode.c:192:6: warning: no previous prototype for 'eventfs_post_create_dir' [-Wmissing-prototypes]
192 | void eventfs_post_create_dir(struct eventfs_file *ef)
| ^~~~~~~~~~~~~~~~~~~~~~~
>> fs/tracefs/event_inode.c:291:5: warning: no previous prototype for 'dcache_dir_open_wrapper' [-Wmissing-prototypes]
291 | int dcache_dir_open_wrapper(struct inode *inode, struct file *file)
| ^~~~~~~~~~~~~~~~~~~~~~~

vim +/eventfs_post_create_dir +192 fs/tracefs/event_inode.c

23
24 /**
25 * eventfs_create_file - create a file in the tracefs filesystem
26 * @name: a pointer to a string containing the name of the file to create.
27 * @mode: the permission that the file should have.
28 * @parent: a pointer to the parent dentry for this file. This should be a
29 * directory dentry if set. If this parameter is NULL, then the
30 * file will be created in the root of the tracefs filesystem.
31 * @data: a pointer to something that the caller will want to get to later
32 * on. The inode.i_private pointer will point to this value on
33 * the open() call.
34 * @fops: a pointer to a struct file_operations that should be used for
35 * this file.
36 *
37 * This is the basic "create a file" function for tracefs. It allows for a
38 * wide range of flexibility in creating a file.
39 *
40 * This function will return a pointer to a dentry if it succeeds. This
41 * pointer must be passed to the tracefs_remove() function when the file is
42 * to be removed (no automatic cleanup happens if your module is unloaded,
43 * you are responsible here.) If an error occurs, %NULL will be returned.
44 *
45 * If tracefs is not enabled in the kernel, the value -%ENODEV will be
46 * returned.
47 */
> 48 struct dentry *eventfs_create_file(const char *name, umode_t mode,
49 struct dentry *parent, void *data,
50 const struct file_operations *fop,
51 bool anon)
52 {
53 struct tracefs_inode *ti;
54 struct dentry *dentry;
55 struct inode *inode;
56
57 if (security_locked_down(LOCKDOWN_TRACEFS))
58 return NULL;
59
60 if (!(mode & S_IFMT))
61 mode |= S_IFREG;
62
63 if (WARN_ON_ONCE(!S_ISREG(mode)))
64 return NULL;
65
66 dentry = eventfs_start_creating(name, parent);
67
68 if (IS_ERR(dentry))
69 return dentry;
70
71 inode = tracefs_get_inode(dentry->d_sb);
72 if (unlikely(!inode))
73 return eventfs_failed_creating(dentry);
74
75 inode->i_mode = mode;
76 inode->i_fop = fop;
77 inode->i_private = data;
78
79 ti = get_tracefs(inode);
80 ti->flags |= TRACEFS_EVENT_INODE;
81
82 if (anon)
83 d_instantiate_anon(dentry, inode);
84 else
85 d_instantiate(dentry, inode);
86
87 fsnotify_create(dentry->d_parent->d_inode, dentry);
88 return eventfs_end_creating(dentry);
89 }
90
91 /**
92 * eventfs_create_dir - create a dir in the tracefs filesystem
93 * @name: a pointer to a string containing the name of the file to create.
94 * @mode: the permission that the file should have.
95 * @parent: a pointer to the parent dentry for this file. This should be a
96 * directory dentry if set. If this parameter is NULL, then the
97 * file will be created in the root of the tracefs filesystem.
98 * @data: a pointer to something that the caller will want to get to later
99 * on. The inode.i_private pointer will point to this value on
100 * the open() call.
101 * @fop: a pointer to a struct file_operations that should be used for
102 * this dir.
103 * @iop: a pointer to a struct inode_operations that should be used for
104 * this dir.
105 *
106 * This is the basic "create a dir" function for eventfs. It allows for a
107 * wide range of flexibility in creating a dir.
108 *
109 * This function will return a pointer to a dentry if it succeeds. This
110 * pointer must be passed to the tracefs_remove() function when the file is
111 * to be removed (no automatic cleanup happens if your module is unloaded,
112 * you are responsible here.) If an error occurs, %NULL will be returned.
113 *
114 * If tracefs is not enabled in the kernel, the value -%ENODEV will be
115 * returned.
116 */
117 struct dentry *eventfs_create_dir(const char *name, umode_t mode,
118 struct dentry *parent, void *data,
119 const struct file_operations *fop,
120 const struct inode_operations *iop,
121 bool anon)
122 {
123 struct tracefs_inode *ti;
124 struct dentry *dentry;
125 struct inode *inode;
126
127 if (security_locked_down(LOCKDOWN_TRACEFS))
128 return NULL;
129
130 WARN_ON(!S_ISDIR(mode));
131
132 dentry = eventfs_start_creating(name, parent);
133
134 if (IS_ERR(dentry))
135 return dentry;
136
137 inode = tracefs_get_inode(dentry->d_sb);
138 if (unlikely(!inode))
139 return eventfs_failed_creating(dentry);
140
141 inode->i_mode = mode;
142 inode->i_op = iop;
143 inode->i_fop = fop;
144 inode->i_private = data;
145
146 ti = get_tracefs(inode);
147 ti->flags |= TRACEFS_EVENT_INODE;
148
149 inc_nlink(inode);
150 if (anon)
151 d_instantiate_anon(dentry, inode);
152 else
153 d_instantiate(dentry, inode);
154 inc_nlink(dentry->d_parent->d_inode);
155 fsnotify_mkdir(dentry->d_parent->d_inode, dentry);
156 return eventfs_end_creating(dentry);
157 }
158
159 /**
160 * eventfs_set_ef_status_free - set the ef->status to free
161 * @dentry: dentry who's status to be freed
162 *
163 * eventfs_set_ef_status_free will be called if no more
164 * reference remains
165 */
166 void eventfs_set_ef_status_free(struct dentry *dentry)
167 {
168 struct tracefs_inode *ti_parent;
169 struct eventfs_inode *ei_parent;
170 struct eventfs_file *ef;
171
172 ti_parent = get_tracefs(dentry->d_parent->d_inode);
173 if (!ti_parent || !(ti_parent->flags & TRACEFS_EVENT_INODE))
174 return;
175 ei_parent = ti_parent->private;
176
177 list_for_each_entry(ef, &ei_parent->e_top_files, list) {
178 if (!strcmp(ef->name, dentry->d_name.name)) {
179 ef->created = false;
180 ef->dentry = NULL;
181 break;
182 }
183 }
184 }
185
186 /**
187 * eventfs_post_create_dir - post create dir routine
188 * @eventfs_file: eventfs_file of recently created dir
189 *
190 * Files with-in eventfs dir should know dentry of parent dir
191 */
> 192 void eventfs_post_create_dir(struct eventfs_file *ef)
193 {
194 struct eventfs_file *ef_child;
195 struct tracefs_inode *ti;
196
197 /* fill parent-child relation */
198 list_for_each_entry(ef_child, &ef->ei->e_top_files, list) {
199 ef_child->d_parent = ef->dentry;
200 }
201
202 ti = get_tracefs(ef->dentry->d_inode);
203 ti->private = ef->ei;
204 }
205
206 /**
207 * eventfs_root_lookup - lookup routine to create file/dir
208 * @dir: directory in which lookup to be done
209 * @dentry: file/dir dentry
210 * @flags:
211 *
212 * Used to create dynamic file/dir with-in @dir, search with-in ei
213 * list, if @dentry found go ahead and create the file/dir
214 */
215
216 static struct dentry *eventfs_root_lookup(struct inode *dir,
217 struct dentry *dentry,
218 unsigned int flags)
219 {
220 struct tracefs_inode *ti;
221 struct eventfs_inode *ei;
222 struct eventfs_file *ef;
223 struct dentry *ret = simple_lookup(dir, dentry, flags);
224
225 ti = get_tracefs(dir);
226 if (!(ti->flags & TRACEFS_EVENT_INODE))
227 return NULL;
228
229 ei = ti->private;
230 list_for_each_entry(ef, &ei->e_top_files, list) {
231 if (strcmp(ef->name, dentry->d_name.name))
232 continue;
233
234 if(ef->created)
235 continue;
236
237 ef->created = true;
238
239 if (ef->ei)
240 ef->dentry = eventfs_create_dir(ef->name, ef->mode, ef->d_parent,
241 ef->data, ef->fop, ef->iop, 0);
242 else
243 ef->dentry = eventfs_create_file(ef->name, ef->mode, ef->d_parent,
244 ef->data, ef->fop, 0);
245
246 if (IS_ERR_OR_NULL(ef->dentry)) {
247 ef->created = false;
248 } else {
249 if (ef->ei)
250 eventfs_post_create_dir(ef);
251 ef->dentry->d_fsdata = ef;
252 dput(ef->dentry);
253 }
254 break;
255 }
256 return ret;
257 }
258
259 /**
260 * eventfs_release - called to release eventfs file/dir
261 * @inode: inode to be released
262 * @file: file to be released (not used)
263 */
264 static int eventfs_release(struct inode *inode, struct file *file)
265 {
266 struct tracefs_inode *ti;
267 struct eventfs_inode *ei;
268 struct eventfs_file *ef;
269
270 ti = get_tracefs(inode);
271 if (!(ti->flags & TRACEFS_EVENT_INODE))
272 return -EINVAL;
273
274 ei = ti->private;
275 list_for_each_entry(ef, &ei->e_top_files, list) {
276 if (ef->created)
277 dput(ef->dentry);
278 }
279 return dcache_dir_close(inode, file);
280 }
281
282 /**
283 * dcache_dir_open_wrapper - eventfs open wrapper
284 * @inode: not used
285 * @file: dir to be opened (to create it's child)
286 *
287 * Used to dynamic create file/dir with-in @file, all the
288 * file/dir will be created. If already created then reference
289 * will be increased
290 */
> 291 int dcache_dir_open_wrapper(struct inode *inode, struct file *file)
292 {
293 struct tracefs_inode *ti;
294 struct eventfs_inode *ei;
295 struct eventfs_file *ef;
296 struct inode *f_inode = file_inode(file);
297 struct dentry *dentry = file_dentry(file);
298
299 ti = get_tracefs(f_inode);
300 if (!(ti->flags & TRACEFS_EVENT_INODE))
301 return -EINVAL;
302
303 ei = ti->private;
304 list_for_each_entry(ef, &ei->e_top_files, list) {
305 if (ef->created) {
306 dget(ef->dentry);
307 continue;
308 }
309
310 ef->created = true;
311
312 inode_lock(dentry->d_inode);
313 if (ef->ei)
314 ef->dentry = eventfs_create_dir(ef->name, ef->mode, dentry,
315 ef->data, ef->fop, ef->iop, 1);
316 else
317 ef->dentry = eventfs_create_file(ef->name, ef->mode, dentry,
318 ef->data, ef->fop, 1);
319 inode_unlock(dentry->d_inode);
320
321 if (IS_ERR_OR_NULL(ef->dentry)) {
322 ef->created = false;
323 } else {
324 if (ef->ei)
325 eventfs_post_create_dir(ef);
326 ef->dentry->d_fsdata = ef;
327 }
328 }
329 return dcache_dir_open(inode, file);
330 }
331

--
0-DAY CI Kernel Test Service