From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B56CBC433EF for ; Mon, 11 Apr 2022 05:12:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S244702AbiDKFOu (ORCPT ); Mon, 11 Apr 2022 01:14:50 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34516 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230030AbiDKFOt (ORCPT ); Mon, 11 Apr 2022 01:14:49 -0400 Received: from smtpbgbr2.qq.com (smtpbgbr2.qq.com [54.207.22.56]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4E85C3EF03 for ; Sun, 10 Apr 2022 22:12:25 -0700 (PDT) X-QQ-mid: bizesmtp73t1649653934thmrjuas Received: from localhost.localdomain ( [58.240.82.166]) by bizesmtp.qq.com (ESMTP) with id ; Mon, 11 Apr 2022 13:12:08 +0800 (CST) X-QQ-SSF: 01400000002000E0J000B00A0000000 X-QQ-FEAT: Ut0pB98mtT/gFdKHPfoA7at3zaJVoBJOhcyE/M+UJ2/MLKcSy/JQcggkV+Krt 0aRzpV2M0Uv+gUPWgYDcXS2fpy2S3WJj+/tBy6WnbI39Iax/LjjW0yveVGjCZBXsv2DkT3x FkRxWIidJVwJyMWfk3AjKBLxU2fyMo2N4evxl2Vu2oTOVWEkwzffZsw0D/HU5kMSO9gYQj/ WX4KaiEdnL5CoNNCqTbuNLpNuzziJ+giSkcEFrSCRLPPVN69P8vzP9JllHI08QM8J6iVmIC zevGiFs8i6YDMr4WdcDyRJ8pCVqgTkY8T9yJdv0xDnyVkJQ6mJuUnWBcXJpXZ6+cFWvvvv2 GW4eb4+0fioZMav/F9T2UX+KIGjQEtKFOgzJbXk X-QQ-GoodBg: 2 From: Meng Tang To: mcgrof@kernel.org, keescook@chromium.org, yzaikin@google.com, nixiaoming@huawei.com Cc: linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, Meng Tang , Davidlohr Bueso Subject: [PATCH] fs/proc: Introduce list_for_each_table_entry for proc sysctl Date: Mon, 11 Apr 2022 13:12:05 +0800 Message-Id: <20220411051205.6694-1-tangmeng@uniontech.com> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-QQ-SENDSIZE: 520 Feedback-ID: bizesmtp:uniontech.com:qybgforeign:qybgforeign8 X-QQ-Bgrelay: 1 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Use the list_for_each_table_entry macro to optimize the scenario of traverse ctl_table. This make the code neater and easier to understand. Suggested-by: Davidlohr Bueso Signed-off-by: Meng Tang --- fs/proc/proc_sysctl.c | 81 +++++++++++++++++++++++++------------------ 1 file changed, 47 insertions(+), 34 deletions(-) diff --git a/fs/proc/proc_sysctl.c b/fs/proc/proc_sysctl.c index fea2561d773b..4f31c68e8ed9 100644 --- a/fs/proc/proc_sysctl.c +++ b/fs/proc/proc_sysctl.c @@ -13,6 +13,9 @@ #include #include "internal.h" +#define list_for_each_table_entry(entry, table) \ + for ((entry) = (table); (entry)->procname; (entry)++) + static const struct dentry_operations proc_sys_dentry_operations; static const struct file_operations proc_sys_file_operations; static const struct inode_operations proc_sys_inode_operations; @@ -170,15 +173,19 @@ static void init_header(struct ctl_table_header *head, head->node = node; if (node) { struct ctl_table *entry; - for (entry = table; entry->procname; entry++, node++) + + list_for_each_table_entry(entry, table) { node->header = head; + node++; + } } } static void erase_header(struct ctl_table_header *head) { struct ctl_table *entry; - for (entry = head->ctl_table; entry->procname; entry++) + + list_for_each_table_entry(entry, head->ctl_table) erase_entry(head, entry); } @@ -192,7 +199,7 @@ static int insert_header(struct ctl_dir *dir, struct ctl_table_header *header) err = insert_links(header); if (err) goto fail_links; - for (entry = header->ctl_table; entry->procname; entry++) { + list_for_each_table_entry(entry, header->ctl_table) { err = insert_entry(header, entry); if (err) goto fail; @@ -989,30 +996,32 @@ static int sysctl_err(const char *path, struct ctl_table *table, char *fmt, ...) static int sysctl_check_table(const char *path, struct ctl_table *table) { + struct ctl_table *entry; int err = 0; - for (; table->procname; table++) { - if (table->child) - err = sysctl_err(path, table, "Not a file"); - - if ((table->proc_handler == proc_dostring) || - (table->proc_handler == proc_dointvec) || - (table->proc_handler == proc_dointvec_minmax) || - (table->proc_handler == proc_dointvec_jiffies) || - (table->proc_handler == proc_dointvec_userhz_jiffies) || - (table->proc_handler == proc_dointvec_ms_jiffies) || - (table->proc_handler == proc_doulongvec_minmax) || - (table->proc_handler == proc_doulongvec_ms_jiffies_minmax)) { - if (!table->data) - err = sysctl_err(path, table, "No data"); - if (!table->maxlen) - err = sysctl_err(path, table, "No maxlen"); + + list_for_each_table_entry(entry, table) { + if (entry->child) + err = sysctl_err(path, entry, "Not a file"); + + if ((entry->proc_handler == proc_dostring) || + (entry->proc_handler == proc_dointvec) || + (entry->proc_handler == proc_dointvec_minmax) || + (entry->proc_handler == proc_dointvec_jiffies) || + (entry->proc_handler == proc_dointvec_userhz_jiffies) || + (entry->proc_handler == proc_dointvec_ms_jiffies) || + (entry->proc_handler == proc_doulongvec_minmax) || + (entry->proc_handler == proc_doulongvec_ms_jiffies_minmax)) { + if (!entry->data) + err = sysctl_err(path, entry, "No data"); + if (!entry->maxlen) + err = sysctl_err(path, entry, "No maxlen"); } - if (!table->proc_handler) - err = sysctl_err(path, table, "No proc_handler"); + if (!entry->proc_handler) + err = sysctl_err(path, entry, "No proc_handler"); - if ((table->mode & (S_IRUGO|S_IWUGO)) != table->mode) - err = sysctl_err(path, table, "bogus .mode 0%o", - table->mode); + if ((entry->mode & (S_IRUGO|S_IWUGO)) != entry->mode) + err = sysctl_err(path, entry, "bogus .mode 0%o", + entry->mode); } return err; } @@ -1028,7 +1037,7 @@ static struct ctl_table_header *new_links(struct ctl_dir *dir, struct ctl_table name_bytes = 0; nr_entries = 0; - for (entry = table; entry->procname; entry++) { + list_for_each_table_entry(entry, table) { nr_entries++; name_bytes += strlen(entry->procname) + 1; } @@ -1045,14 +1054,16 @@ static struct ctl_table_header *new_links(struct ctl_dir *dir, struct ctl_table node = (struct ctl_node *)(links + 1); link_table = (struct ctl_table *)(node + nr_entries); link_name = (char *)&link_table[nr_entries + 1]; + link = link_table; - for (link = link_table, entry = table; entry->procname; link++, entry++) { + list_for_each_table_entry(entry, table) { int len = strlen(entry->procname) + 1; memcpy(link_name, entry->procname, len); link->procname = link_name; link->mode = S_IFLNK|S_IRWXUGO; link->data = link_root; link_name += len; + link++; } init_header(links, dir->header.root, dir->header.set, node, link_table); links->nreg = nr_entries; @@ -1067,7 +1078,7 @@ static bool get_links(struct ctl_dir *dir, struct ctl_table *entry, *link; /* Are there links available for every entry in table? */ - for (entry = table; entry->procname; entry++) { + list_for_each_table_entry(entry, table) { const char *procname = entry->procname; link = find_entry(&head, dir, procname, strlen(procname)); if (!link) @@ -1080,7 +1091,7 @@ static bool get_links(struct ctl_dir *dir, } /* The checks passed. Increase the registration count on the links */ - for (entry = table; entry->procname; entry++) { + list_for_each_table_entry(entry, table) { const char *procname = entry->procname; link = find_entry(&head, dir, procname, strlen(procname)); head->nreg++; @@ -1183,7 +1194,7 @@ struct ctl_table_header *__register_sysctl_table( struct ctl_node *node; int nr_entries = 0; - for (entry = table; entry->procname; entry++) + list_for_each_table_entry(entry, table) nr_entries++; header = kzalloc(sizeof(struct ctl_table_header) + @@ -1278,7 +1289,7 @@ static int count_subheaders(struct ctl_table *table) if (!table || !table->procname) return 1; - for (entry = table; entry->procname; entry++) { + list_for_each_table_entry(entry, table) { if (entry->child) nr_subheaders += count_subheaders(entry->child); else @@ -1297,7 +1308,7 @@ static int register_leaf_sysctl_tables(const char *path, char *pos, int nr_dirs = 0; int err = -ENOMEM; - for (entry = table; entry->procname; entry++) { + list_for_each_table_entry(entry, table) { if (entry->child) nr_dirs++; else @@ -1314,7 +1325,9 @@ static int register_leaf_sysctl_tables(const char *path, char *pos, goto out; ctl_table_arg = files; - for (new = files, entry = table; entry->procname; entry++) { + new = files; + + list_for_each_table_entry(entry, table) { if (entry->child) continue; *new = *entry; @@ -1338,7 +1351,7 @@ static int register_leaf_sysctl_tables(const char *path, char *pos, } /* Recurse into the subdirectories. */ - for (entry = table; entry->procname; entry++) { + list_for_each_table_entry(entry, table) { char *child_pos; if (!entry->child) @@ -1483,7 +1496,7 @@ static void put_links(struct ctl_table_header *header) if (IS_ERR(core_parent)) return; - for (entry = header->ctl_table; entry->procname; entry++) { + list_for_each_table_entry(entry, header->ctl_table) { struct ctl_table_header *link_head; struct ctl_table *link; const char *name = entry->procname; -- 2.20.1