Commit cb55f27a authored by Meng Tang's avatar Meng Tang Committed by Luis Chamberlain
Browse files

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: default avatarDavidlohr <Bueso&lt;dave@stgolabs.net>
Signed-off-by: default avatarMeng Tang <tangmeng@uniontech.com>
[updated the sysctl_check_table() hunk due to some changes upstream]
Signed-off-by: default avatarLuis Chamberlain <mcgrof@kernel.org>
parent 3c6a4cba

fs/proc/proc_sysctl.c

+50 −38
Original line number Diff line number Diff line
@@ -19,6 +19,9 @@ 
#include <linux/kmemleak.h>

#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;