static const struct inode_operations proc_sys_dir_operations;
/* Support for permanently empty directories */
-
-struct ctl_table sysctl_mount_point[] = {
- { }
+static struct ctl_table sysctl_mount_point[] = {
+ {.type = SYSCTL_TABLE_TYPE_PERMANENTLY_EMPTY }
};
/**
}
EXPORT_SYMBOL(register_sysctl_mount_point);
-static bool is_empty_dir(struct ctl_table_header *head)
-{
- return head->ctl_table[0].child == sysctl_mount_point;
-}
-
-static void set_empty_dir(struct ctl_dir *dir)
-{
- dir->header.ctl_table[0].child = sysctl_mount_point;
-}
-
-static void clear_empty_dir(struct ctl_dir *dir)
-
-{
- dir->header.ctl_table[0].child = NULL;
-}
+#define sysctl_is_perm_empty_ctl_table(tptr) \
+ (tptr[0].type == SYSCTL_TABLE_TYPE_PERMANENTLY_EMPTY)
+#define sysctl_is_perm_empty_ctl_header(hptr) \
+ (sysctl_is_perm_empty_ctl_table(hptr->ctl_table))
+#define sysctl_set_perm_empty_ctl_header(hptr) \
+ (hptr->ctl_table[0].type = SYSCTL_TABLE_TYPE_PERMANENTLY_EMPTY)
+#define sysctl_clear_perm_empty_ctl_header(hptr) \
+ (hptr->ctl_table[0].type = SYSCTL_TABLE_TYPE_DEFAULT)
void proc_sys_poll_notify(struct ctl_table_poll *poll)
{
static int insert_header(struct ctl_dir *dir, struct ctl_table_header *header)
{
struct ctl_table *entry;
+ struct ctl_table_header *dir_h = &dir->header;
int err;
+
/* Is this a permanently empty directory? */
- if (is_empty_dir(&dir->header))
+ if (sysctl_is_perm_empty_ctl_header(dir_h))
return -EROFS;
/* Am I creating a permanently empty directory? */
- if (header->ctl_table == sysctl_mount_point) {
+ if (sysctl_is_perm_empty_ctl_table(header->ctl_table)) {
if (!RB_EMPTY_ROOT(&dir->root))
return -EINVAL;
- set_empty_dir(dir);
+ sysctl_set_perm_empty_ctl_header(dir_h);
}
- dir->header.nreg++;
+ dir_h->nreg++;
header->parent = dir;
err = insert_links(header);
if (err)
put_links(header);
fail_links:
if (header->ctl_table == sysctl_mount_point)
- clear_empty_dir(dir);
+ sysctl_clear_perm_empty_ctl_header(dir_h);
header->parent = NULL;
- drop_sysctl_table(&dir->header);
+ drop_sysctl_table(dir_h);
return err;
}
inode->i_mode |= S_IFDIR;
inode->i_op = &proc_sys_dir_operations;
inode->i_fop = &proc_sys_dir_file_operations;
- if (is_empty_dir(head))
+ if (sysctl_is_perm_empty_ctl_header(head))
make_empty_dir_inode(inode);
}
struct ctl_table *entry;
int err = 0;
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_dobool) ||
(entry->proc_handler == proc_dointvec) ||
spin_unlock(&sysctl_lock);
fail:
kfree(header);
- dump_stack();
return NULL;
}
kmemleak_not_leak(hdr);
}
-static char *append_path(const char *path, char *pos, const char *name)
-{
- int namelen;
- namelen = strlen(name);
- if (((pos - path) + namelen + 2) >= PATH_MAX)
- return NULL;
- memcpy(pos, name, namelen);
- pos[namelen] = '/';
- pos[namelen + 1] = '\0';
- pos += namelen + 1;
- return pos;
-}
-
-static int count_subheaders(struct ctl_table *table)
-{
- int has_files = 0;
- int nr_subheaders = 0;
- struct ctl_table *entry;
-
- /* special case: no directory and empty directory */
- if (!table || !table->procname)
- return 1;
-
- list_for_each_table_entry(entry, table) {
- if (entry->child)
- nr_subheaders += count_subheaders(entry->child);
- else
- has_files = 1;
- }
- return nr_subheaders + has_files;
-}
-
-static int register_leaf_sysctl_tables(const char *path, char *pos,
- struct ctl_table_header ***subheader, struct ctl_table_set *set,
- struct ctl_table *table)
-{
- struct ctl_table *ctl_table_arg = NULL;
- struct ctl_table *entry, *files;
- int nr_files = 0;
- int nr_dirs = 0;
- int err = -ENOMEM;
-
- list_for_each_table_entry(entry, table) {
- if (entry->child)
- nr_dirs++;
- else
- nr_files++;
- }
-
- files = table;
- /* If there are mixed files and directories we need a new table */
- if (nr_dirs && nr_files) {
- struct ctl_table *new;
- files = kcalloc(nr_files + 1, sizeof(struct ctl_table),
- GFP_KERNEL);
- if (!files)
- goto out;
-
- ctl_table_arg = files;
- new = files;
-
- list_for_each_table_entry(entry, table) {
- if (entry->child)
- continue;
- *new = *entry;
- new++;
- }
- }
-
- /* Register everything except a directory full of subdirectories */
- if (nr_files || !nr_dirs) {
- struct ctl_table_header *header;
- header = __register_sysctl_table(set, path, files);
- if (!header) {
- kfree(ctl_table_arg);
- goto out;
- }
-
- /* Remember if we need to free the file table */
- header->ctl_table_arg = ctl_table_arg;
- **subheader = header;
- (*subheader)++;
- }
-
- /* Recurse into the subdirectories. */
- list_for_each_table_entry(entry, table) {
- char *child_pos;
-
- if (!entry->child)
- continue;
-
- err = -ENAMETOOLONG;
- child_pos = append_path(path, pos, entry->procname);
- if (!child_pos)
- goto out;
-
- err = register_leaf_sysctl_tables(path, child_pos, subheader,
- set, entry->child);
- pos[0] = '\0';
- if (err)
- goto out;
- }
- err = 0;
-out:
- /* On failure our caller will unregister all registered subheaders */
- return err;
-}
-
-/**
- * register_sysctl_table - register a sysctl table hierarchy
- * @table: the top-level table structure
- *
- * Register a sysctl table hierarchy. @table should be a filled in ctl_table
- * array. A completely 0 filled entry terminates the table.
- * We are slowly deprecating this call so avoid its use.
- */
-struct ctl_table_header *register_sysctl_table(struct ctl_table *table)
-{
- struct ctl_table *ctl_table_arg = table;
- int nr_subheaders = count_subheaders(table);
- struct ctl_table_header *header = NULL, **subheaders, **subheader;
- char *new_path, *pos;
-
- pos = new_path = kmalloc(PATH_MAX, GFP_KERNEL);
- if (!new_path)
- return NULL;
-
- pos[0] = '\0';
- while (table->procname && table->child && !table[1].procname) {
- pos = append_path(new_path, pos, table->procname);
- if (!pos)
- goto out;
- table = table->child;
- }
- if (nr_subheaders == 1) {
- header = __register_sysctl_table(&sysctl_table_root.default_set, new_path, table);
- if (header)
- header->ctl_table_arg = ctl_table_arg;
- } else {
- header = kzalloc(sizeof(*header) +
- sizeof(*subheaders)*nr_subheaders, GFP_KERNEL);
- if (!header)
- goto out;
-
- subheaders = (struct ctl_table_header **) (header + 1);
- subheader = subheaders;
- header->ctl_table_arg = ctl_table_arg;
-
- if (register_leaf_sysctl_tables(new_path, pos, &subheader,
- &sysctl_table_root.default_set, table))
- goto err_register_leaves;
- }
-
-out:
- kfree(new_path);
- return header;
-
-err_register_leaves:
- while (subheader > subheaders) {
- struct ctl_table_header *subh = *(--subheader);
- struct ctl_table *table = subh->ctl_table_arg;
- unregister_sysctl_table(subh);
- kfree(table);
- }
- kfree(header);
- header = NULL;
- goto out;
-}
-EXPORT_SYMBOL(register_sysctl_table);
-
-int __register_sysctl_base(struct ctl_table *base_table)
-{
- struct ctl_table_header *hdr;
-
- hdr = register_sysctl_table(base_table);
- kmemleak_not_leak(hdr);
- return 0;
-}
-
static void put_links(struct ctl_table_header *header)
{
struct ctl_table_set *root_set = &sysctl_table_root.default_set;
/**
* unregister_sysctl_table - unregister a sysctl table hierarchy
- * @header: the header returned from register_sysctl_table
+ * @header: the header returned from register_sysctl or __register_sysctl_table
*
* Unregisters the sysctl table and all children. proc entries may not
* actually be removed until they are no longer used by anyone.
*/
void unregister_sysctl_table(struct ctl_table_header * header)
{
- int nr_subheaders;
might_sleep();
if (header == NULL)
return;
- nr_subheaders = count_subheaders(header->ctl_table_arg);
- if (unlikely(nr_subheaders > 1)) {
- struct ctl_table_header **subheaders;
- int i;
-
- subheaders = (struct ctl_table_header **)(header + 1);
- for (i = nr_subheaders -1; i >= 0; i--) {
- struct ctl_table_header *subh = subheaders[i];
- struct ctl_table *table = subh->ctl_table_arg;
- unregister_sysctl_table(subh);
- kfree(table);
- }
- kfree(header);
- return;
- }
-
spin_lock(&sysctl_lock);
drop_sysctl_table(header);
spin_unlock(&sysctl_lock);
projects / platform / kernel / linux-rpi.git / blobdiff