11 #include <linux/file.h>
42 /* SLAB cache for file structures */
47 /* Container for backing file with optional user path */
49 	struct file file;  member
53 static inline struct backing_file *backing_file(struct file *f)  in backing_file()
55 	return container_of(f, struct backing_file, file);  in backing_file()
58 struct path *backing_file_user_path(struct file *f)  in backing_file_user_path()
64 static inline void file_free(struct file *f)  in file_free()
109 		.procname	= "file-nr",
116 		.procname	= "file-max",
148 static int init_file(struct file *f, int flags, const struct cred *cred)  in init_file()
169 	 * refcount bumps we should reinitialize the reused file first.  in init_file()
175 /* Find an unused file structure and return a pointer to it.
176  * Returns an error pointer if some error happend e.g. we over file
185 struct file *alloc_empty_file(int flags, const struct cred *cred)  in alloc_empty_file()
188 	struct file *f;  in alloc_empty_file()
220 		pr_info("VFS: file-max limit %lu reached\n", get_max_files());  in alloc_empty_file()
229  * This is only for kernel internal use, and the allocate file must not be
230  * installed into file tables or such.
232 struct file *alloc_empty_file_noaccount(int flags, const struct cred *cred)  in alloc_empty_file_noaccount()
234 	struct file *f;  in alloc_empty_file_noaccount()
256  * This is only for kernel internal use, and the allocate file must not be
257  * installed into file tables or such.
259 struct file *alloc_empty_backing_file(int flags, const struct cred *cred)  in alloc_empty_backing_file()
268 	error = init_file(&ff->file, flags, cred);  in alloc_empty_backing_file()
274 	ff->file.f_mode |= FMODE_BACKING | FMODE_NOACCOUNT;  in alloc_empty_backing_file()
275 	return &ff->file;  in alloc_empty_backing_file()
279  * alloc_file - allocate and initialize a 'struct file'
281  * @path: the (dentry, vfsmount) pair for the new file
282  * @flags: O_... flags with which the new file will be opened
283  * @fop: the 'struct file_operations' for the new file
285 static struct file *alloc_file(const struct path *path, int flags,  in alloc_file()
288 	struct file *file;  in alloc_file()  local
290 	file = alloc_empty_file(flags, current_cred());  in alloc_file()
291 	if (IS_ERR(file))  in alloc_file()
292 		return file;  in alloc_file()
294 	file->f_path = *path;  in alloc_file()
295 	file->f_inode = path->dentry->d_inode;  in alloc_file()
296 	file->f_mapping = path->dentry->d_inode->i_mapping;  in alloc_file()
297 	file->f_wb_err = filemap_sample_wb_err(file->f_mapping);  in alloc_file()
298 	file->f_sb_err = file_sample_sb_err(file);  in alloc_file()
300 		file->f_mode |= FMODE_LSEEK;  in alloc_file()
301 	if ((file->f_mode & FMODE_READ) &&  in alloc_file()
303 		file->f_mode |= FMODE_CAN_READ;  in alloc_file()
304 	if ((file->f_mode & FMODE_WRITE) &&  in alloc_file()
306 		file->f_mode |= FMODE_CAN_WRITE;  in alloc_file()
307 	file->f_iocb_flags = iocb_flags(file);  in alloc_file()
308 	file->f_mode |= FMODE_OPENED;  in alloc_file()
309 	file->f_op = fop;  in alloc_file()
310 	if ((file->f_mode & (FMODE_READ | FMODE_WRITE)) == FMODE_READ)  in alloc_file()
312 	return file;  in alloc_file()
315 struct file *alloc_file_pseudo(struct inode *inode, struct vfsmount *mnt,  in alloc_file_pseudo()
321 	struct file *file;  in alloc_file_pseudo()  local
328 	file = alloc_file(&path, flags, fops);  in alloc_file_pseudo()
329 	if (IS_ERR(file)) {  in alloc_file_pseudo()
333 	return file;  in alloc_file_pseudo()
337 struct file *alloc_file_clone(struct file *base, int flags,  in alloc_file_clone()
340 	struct file *f = alloc_file(&base->f_path, flags, fops);  in alloc_file_clone()
348 /* the real guts of fput() - releasing the last reference to file
350 static void __fput(struct file *file)  in __fput()  argument
352 	struct dentry *dentry = file->f_path.dentry;  in __fput()
353 	struct vfsmount *mnt = file->f_path.mnt;  in __fput()
354 	struct inode *inode = file->f_inode;  in __fput()
355 	fmode_t mode = file->f_mode;  in __fput()
357 	if (unlikely(!(file->f_mode & FMODE_OPENED)))  in __fput()
362 	fsnotify_close(file);  in __fput()
365 	 * in the file cleanup chain.  in __fput()
367 	eventpoll_release(file);  in __fput()
368 	locks_remove_file(file);  in __fput()
370 	ima_file_free(file);  in __fput()
371 	if (unlikely(file->f_flags & FASYNC)) {  in __fput()
372 		if (file->f_op->fasync)  in __fput()
373 			file->f_op->fasync(-1, file, 0);  in __fput()
375 	if (file->f_op->release)  in __fput()
376 		file->f_op->release(inode, file);  in __fput()
381 	fops_put(file->f_op);  in __fput()
382 	put_pid(file->f_owner.pid);  in __fput()
383 	put_file_access(file);  in __fput()
389 	file_free(file);  in __fput()
396 	struct file *f, *t;  in delayed_fput()
404 	__fput(container_of(work, struct file, f_task_work));  in ____fput()
411  * not left us with opened struct file waiting for __fput() - execve()
425 void fput(struct file *file)  in fput()  argument
427 	if (atomic_long_dec_and_test(&file->f_count)) {  in fput()
430 		if (unlikely(!(file->f_mode & (FMODE_BACKING | FMODE_OPENED)))) {  in fput()
431 			file_free(file);  in fput()
435 			init_task_work(&file->f_task_work, ____fput);  in fput()
436 			if (!task_work_add(task, &file->f_task_work, TWA_RESUME))  in fput()
441 			 * fput to avoid leaking *file.  in fput()
445 		if (llist_add(&file->f_llist, &delayed_fput_list))  in fput()
454  * for this specific struct file it won't involve anything that would
458 void __fput_sync(struct file *file)  in __fput_sync()  argument
460 	if (atomic_long_dec_and_test(&file->f_count))  in __fput_sync()
461 		__fput(file);  in __fput_sync()
469 	filp_cachep = kmem_cache_create("filp", sizeof(struct file), 0,  in files_init()
476  * One file with associated inode and dcache is very roughly 1K. Per default