From cb55f27ac9326bfe3bcaaf0adb498778d64602b6 Mon Sep 17 00:00:00 2001 From: Meng Tang Date: Mon, 11 Apr 2022 13:12:05 +0800 Subject: fs/proc: Introduce list_for_each_table_entry for proc sysctl 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 [updated the sysctl_check_table() hunk due to some changes upstream] Signed-off-by: Luis Chamberlain --- fs/proc/proc_sysctl.c | 88 +++++++++++++++++++++++++++++---------------------- 1 file changed, 50 insertions(+), 38 deletions(-) (limited to 'fs') diff --git a/fs/proc/proc_sysctl.c b/fs/proc/proc_sysctl.c index 7d9cfc730bd4..8901fe0b7e2a 100644 --- a/fs/proc/proc_sysctl.c +++ b/fs/proc/proc_sysctl.c @@ -19,6 +19,9 @@ #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; @@ -215,15 +218,19 @@ static void init_header(struct ctl_table_header *head, INIT_HLIST_HEAD(&head->inodes); 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); } @@ -248,7 +255,7 @@ 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; @@ -1130,35 +1137,36 @@ static int sysctl_check_table_array(const char *path, struct ctl_table *table) 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_douintvec) || - (table->proc_handler == proc_douintvec_minmax) || - (table->proc_handler == proc_dointvec_minmax) || - (table->proc_handler == proc_dou8vec_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_douintvec) || + (entry->proc_handler == proc_douintvec_minmax) || + (entry->proc_handler == proc_dointvec_minmax) || + (entry->proc_handler == proc_dou8vec_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"); else - err |= sysctl_check_table_array(path, table); + err |= sysctl_check_table_array(path, entry); } - 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; } @@ -1174,7 +1182,7 @@ 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; } @@ -1191,14 +1199,16 @@ 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; @@ -1213,7 +1223,7 @@ 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) @@ -1226,7 +1236,7 @@ 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++; @@ -1329,7 +1339,7 @@ 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) + @@ -1456,7 +1466,7 @@ 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 @@ -1475,7 +1485,7 @@ 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 @@ -1492,7 +1502,9 @@ 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; @@ -1516,7 +1528,7 @@ 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) @@ -1670,7 +1682,7 @@ 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; -- cgit v1.2.3 From acd0b04ecc795e97b7878dccc5cb4d3d627a4c27 Mon Sep 17 00:00:00 2001 From: Vasily Averin Date: Sun, 24 Apr 2022 21:28:54 +0300 Subject: sysctl: minor cleanup in new_dir() Byte zeroing is not required here, since memory was allocated by kzalloc() Signed-off-by: Vasily Averin Signed-off-by: Luis Chamberlain --- fs/proc/proc_sysctl.c | 1 - 1 file changed, 1 deletion(-) (limited to 'fs') diff --git a/fs/proc/proc_sysctl.c b/fs/proc/proc_sysctl.c index 8901fe0b7e2a..f5b12adee69d 100644 --- a/fs/proc/proc_sysctl.c +++ b/fs/proc/proc_sysctl.c @@ -985,7 +985,6 @@ static struct ctl_dir *new_dir(struct ctl_table_set *set, table = (struct ctl_table *)(node + 1); new_name = (char *)(table + 2); memcpy(new_name, name, namelen); - new_name[namelen] = '\0'; table[0].procname = new_name; table[0].mode = S_IFDIR|S_IRUGO|S_IXUGO; init_header(&new->header, set->dir.header.root, set, node, table); -- cgit v1.2.3