1 /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ 2 /* 3 * 4 * (C) COPYRIGHT 2017, 2020-2022 ARM Limited. All rights reserved. 5 * 6 * This program is free software and is provided to you under the terms of the 7 * GNU General Public License version 2 as published by the Free Software 8 * Foundation, and any use by you of this program is subject to the terms 9 * of such GNU license. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program; if not, you can access it online at 18 * http://www.gnu.org/licenses/gpl-2.0.html. 19 * 20 */ 21 22 #ifndef _KERNEL_UTF_HELPERS_H_ 23 #define _KERNEL_UTF_HELPERS_H_ 24 25 /* kutf_helpers.h 26 * Test helper functions for the kernel UTF test infrastructure. 27 * 28 * These functions provide methods for enqueuing/dequeuing lines of text sent 29 * by user space. They are used to implement the transfer of "userdata" from 30 * user space to kernel. 31 */ 32 33 #include <kutf/kutf_suite.h> 34 #include <linux/device.h> 35 36 /** 37 * kutf_helper_pending_input() - Check any pending lines sent by user space 38 * @context: KUTF context 39 * 40 * Return: true if there are pending lines, otherwise false 41 */ 42 bool kutf_helper_pending_input(struct kutf_context *context); 43 44 /** 45 * kutf_helper_input_dequeue() - Dequeue a line sent by user space 46 * @context: KUTF context 47 * @str_size: Pointer to an integer to receive the size of the string 48 * 49 * If no line is available then this function will wait (interruptibly) until 50 * a line is available. 51 * 52 * Return: The line dequeued, ERR_PTR(-EINTR) if interrupted or NULL on end 53 * of data. 54 */ 55 char *kutf_helper_input_dequeue(struct kutf_context *context, size_t *str_size); 56 57 /** 58 * kutf_helper_input_enqueue() - Enqueue a line sent by user space 59 * @context: KUTF context 60 * @str: The user space address of the line 61 * @size: The length in bytes of the string 62 * 63 * This function will use copy_from_user to copy the string out of user space. 64 * The string need not be NULL-terminated (@size should not include the NULL 65 * termination). 66 * 67 * As a special case @str==NULL and @size==0 is valid to mark the end of input, 68 * but callers should use kutf_helper_input_enqueue_end_of_data() instead. 69 * 70 * Return: 0 on success, -EFAULT if the line cannot be copied from user space, 71 * -ENOMEM if out of memory. 72 */ 73 int kutf_helper_input_enqueue(struct kutf_context *context, 74 const char __user *str, size_t size); 75 76 /** 77 * kutf_helper_input_enqueue_end_of_data() - Signal no more data is to be sent 78 * @context: KUTF context 79 * 80 * After this function has been called, kutf_helper_input_dequeue() will always 81 * return NULL. 82 */ 83 void kutf_helper_input_enqueue_end_of_data(struct kutf_context *context); 84 85 /** 86 * kutf_helper_ignore_dmesg() - Write message in dmesg to instruct parser 87 * to ignore errors, until the counterpart 88 * is written to dmesg to stop ignoring errors. 89 * @dev: Device pointer to write to dmesg using. 90 * 91 * This function writes "Start ignoring dmesg warnings" to dmesg, which 92 * the parser will read and not log any errors. Only to be used in cases where 93 * we expect an error to be produced in dmesg but that we do not want to be 94 * flagged as an error. 95 */ 96 void kutf_helper_ignore_dmesg(struct device *dev); 97 98 /** 99 * kutf_helper_stop_ignoring_dmesg() - Write message in dmesg to instruct parser 100 * to stop ignoring errors. 101 * @dev: Device pointer to write to dmesg using. 102 * 103 * This function writes "Stop ignoring dmesg warnings" to dmesg, which 104 * the parser will read and continue to log any errors. Counterpart to 105 * kutf_helper_ignore_dmesg(). 106 */ 107 void kutf_helper_stop_ignoring_dmesg(struct device *dev); 108 109 #endif /* _KERNEL_UTF_HELPERS_H_ */ 110