static struct ctl_table root_table[] = {
{
.procname = "",
- .mode = S_IRUGO|S_IXUGO,
- .child = &root_table[1],
+ .mode = S_IFDIR|S_IRUGO|S_IXUGO,
},
{ }
};
static struct ctl_table_root sysctl_table_root;
-static struct ctl_table_header root_table_header = {
- {{.count = 1,
- .nreg = 1,
- .ctl_table = root_table,
- .ctl_entry = LIST_HEAD_INIT(sysctl_table_root.default_set.list),}},
- .root = &sysctl_table_root,
- .set = &sysctl_table_root.default_set,
+static struct ctl_dir sysctl_root_dir = {
+ .header = {
+ {{.count = 1,
+ .nreg = 1,
+ .ctl_table = root_table,
+ .ctl_entry = LIST_HEAD_INIT(sysctl_table_root.default_set.list),}},
+ .root = &sysctl_table_root,
+ .set = &sysctl_table_root.default_set,
+ },
};
static struct ctl_table_root sysctl_table_root = {
.root_list = LIST_HEAD_INIT(sysctl_table_root.root_list),
- .default_set.list = LIST_HEAD_INIT(root_table_header.ctl_entry),
+ .default_set.list = LIST_HEAD_INIT(sysctl_root_dir.header.ctl_entry),
.default_set.root = &sysctl_table_root,
};
static DEFINE_SPINLOCK(sysctl_lock);
+static void drop_sysctl_table(struct ctl_table_header *header);
+
static int namecmp(const char *name1, int len1, const char *name2, int len2)
{
int minlen;
}
static struct ctl_table *find_entry(struct ctl_table_header **phead,
- struct ctl_table_set *set,
- struct ctl_table_header *dir_head, struct ctl_table *dir,
+ struct ctl_table_set *set, struct ctl_dir *dir,
const char *name, int namelen)
{
struct ctl_table_header *head;
struct ctl_table *entry;
- if (dir_head->set == set) {
- for (entry = dir; entry->procname; entry++) {
- const char *procname = entry->procname;
- if (namecmp(procname, strlen(procname), name, namelen) == 0) {
- *phead = dir_head;
- return entry;
- }
- }
- }
-
list_for_each_entry(head, &set->list, ctl_entry) {
if (head->unregistering)
continue;
- if (head->attached_to != dir)
+ if (head->parent != dir)
continue;
- for (entry = head->attached_by; entry->procname; entry++) {
+ for (entry = head->ctl_table; entry->procname; entry++) {
const char *procname = entry->procname;
if (namecmp(procname, strlen(procname), name, namelen) == 0) {
*phead = head;
struct ctl_table_root *root, struct ctl_table_set *set,
struct ctl_table *table)
{
+ head->ctl_table = table;
head->ctl_table_arg = table;
INIT_LIST_HEAD(&head->ctl_entry);
head->used = 0;
list_del_init(&head->ctl_entry);
}
-static void insert_header(struct ctl_table_header *header)
+static void insert_header(struct ctl_dir *dir, struct ctl_table_header *header)
{
- header->parent->count++;
+ header->parent = dir;
+ header->parent->header.nreg++;
list_add_tail(&header->ctl_entry, &header->set->list);
}
}
static struct ctl_table *lookup_entry(struct ctl_table_header **phead,
- struct ctl_table_header *dir_head,
- struct ctl_table *dir,
+ struct ctl_dir *dir,
const char *name, int namelen)
{
struct ctl_table_header *head;
root = &sysctl_table_root;
do {
set = lookup_header_set(root, current->nsproxy);
- entry = find_entry(&head, set, dir_head, dir, name, namelen);
+ entry = find_entry(&head, set, dir, name, namelen);
if (entry && use_table(head))
*phead = head;
else
return entry;
}
-static struct ctl_table_header *next_usable_entry(struct ctl_table *dir,
+static struct ctl_table_header *next_usable_entry(struct ctl_dir *dir,
struct ctl_table_root *root, struct list_head *tmp)
{
struct nsproxy *namespaces = current->nsproxy;
head = list_entry(tmp, struct ctl_table_header, ctl_entry);
root = head->root;
- if (head->attached_to != dir ||
- !head->attached_by->procname ||
+ if (head->parent != dir ||
+ !head->ctl_table->procname ||
!use_table(head))
goto next;
return NULL;
}
-static void first_entry(
- struct ctl_table_header *dir_head, struct ctl_table *dir,
+static void first_entry(struct ctl_dir *dir,
struct ctl_table_header **phead, struct ctl_table **pentry)
{
- struct ctl_table_header *head = dir_head;
- struct ctl_table *entry = dir;
+ struct ctl_table_header *head;
+ struct ctl_table *entry = NULL;
spin_lock(&sysctl_lock);
- if (entry->procname) {
- use_table(head);
- } else {
- head = next_usable_entry(dir, &sysctl_table_root,
- &sysctl_table_root.default_set.list);
- if (head)
- entry = head->attached_by;
- }
+ head = next_usable_entry(dir, &sysctl_table_root,
+ &sysctl_table_root.default_set.list);
spin_unlock(&sysctl_lock);
+ if (head)
+ entry = head->ctl_table;
*phead = head;
*pentry = entry;
}
-static void next_entry(struct ctl_table *dir,
- struct ctl_table_header **phead, struct ctl_table **pentry)
+static void next_entry(struct ctl_table_header **phead, struct ctl_table **pentry)
{
struct ctl_table_header *head = *phead;
struct ctl_table *entry = *pentry;
entry++;
if (!entry->procname) {
- struct ctl_table_root *root = head->root;
- struct list_head *tmp = &head->ctl_entry;
- if (head->attached_to != dir) {
- root = &sysctl_table_root;
- tmp = &sysctl_table_root.default_set.list;
- }
spin_lock(&sysctl_lock);
unuse_table(head);
- head = next_usable_entry(dir, root, tmp);
+ head = next_usable_entry(head->parent, head->root, &head->ctl_entry);
spin_unlock(&sysctl_lock);
if (head)
- entry = head->attached_by;
+ entry = head->ctl_table;
}
*phead = head;
*pentry = entry;
inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
inode->i_mode = table->mode;
- if (!table->child) {
+ if (!S_ISDIR(table->mode)) {
inode->i_mode |= S_IFREG;
inode->i_op = &proc_sys_inode_operations;
inode->i_fop = &proc_sys_file_operations;
{
struct ctl_table_header *head = PROC_I(inode)->sysctl;
if (!head)
- head = &root_table_header;
+ head = &sysctl_root_dir.header;
return sysctl_head_grab(head);
}
struct nameidata *nd)
{
struct ctl_table_header *head = grab_header(dir);
- struct ctl_table *table = PROC_I(dir)->sysctl_entry;
struct ctl_table_header *h = NULL;
struct qstr *name = &dentry->d_name;
struct ctl_table *p;
struct inode *inode;
struct dentry *err = ERR_PTR(-ENOENT);
+ struct ctl_dir *ctl_dir;
if (IS_ERR(head))
return ERR_CAST(head);
- if (table && !table->child) {
- WARN_ON(1);
- goto out;
- }
+ ctl_dir = container_of(head, struct ctl_dir, header);
- table = table ? table->child : &head->ctl_table[1];
-
- p = lookup_entry(&h, head, table, name->name, name->len);
+ p = lookup_entry(&h, ctl_dir, name->name, name->len);
if (!p)
goto out;
struct dentry *dentry = filp->f_path.dentry;
struct inode *inode = dentry->d_inode;
struct ctl_table_header *head = grab_header(inode);
- struct ctl_table *table = PROC_I(inode)->sysctl_entry;
struct ctl_table_header *h = NULL;
struct ctl_table *entry;
+ struct ctl_dir *ctl_dir;
unsigned long pos;
int ret = -EINVAL;
if (IS_ERR(head))
return PTR_ERR(head);
- if (table && !table->child) {
- WARN_ON(1);
- goto out;
- }
-
- table = table ? table->child : &head->ctl_table[1];
+ ctl_dir = container_of(head, struct ctl_dir, header);
ret = 0;
/* Avoid a switch here: arm builds fail with missing __cmpdi2 */
}
pos = 2;
- for (first_entry(head, table, &h, &entry); h; next_entry(table, &h, &entry)) {
+ for (first_entry(ctl_dir, &h, &entry); h; next_entry(&h, &entry)) {
ret = scan(h, entry, &pos, filp, dirent, filldir);
if (ret) {
sysctl_head_finish(h);
.d_compare = proc_sys_compare,
};
-static struct ctl_table *is_branch_in(struct ctl_table *branch,
- struct ctl_table *table)
+static struct ctl_dir *find_subdir(struct ctl_table_set *set, struct ctl_dir *dir,
+ const char *name, int namelen)
{
- struct ctl_table *p;
- const char *s = branch->procname;
+ struct ctl_table_header *head;
+ struct ctl_table *entry;
- /* branch should have named subdirectory as its first element */
- if (!s || !branch->child)
- return NULL;
+ entry = find_entry(&head, set, dir, name, namelen);
+ if (!entry)
+ return ERR_PTR(-ENOENT);
+ if (S_ISDIR(entry->mode))
+ return container_of(head, struct ctl_dir, header);
+ return ERR_PTR(-ENOTDIR);
+}
+
+static struct ctl_dir *new_dir(struct ctl_table_set *set,
+ const char *name, int namelen)
+{
+ struct ctl_table *table;
+ struct ctl_dir *new;
+ char *new_name;
- /* ... and nothing else */
- if (branch[1].procname)
+ new = kzalloc(sizeof(*new) + sizeof(struct ctl_table)*2 +
+ namelen + 1, GFP_KERNEL);
+ if (!new)
return NULL;
- /* table should contain subdirectory with the same name */
- for (p = table; p->procname; p++) {
- if (!p->child)
- continue;
- if (p->procname && strcmp(p->procname, s) == 0)
- return p;
- }
- return NULL;
+ table = (struct ctl_table *)(new + 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->root, set, table);
+
+ return new;
}
-/* see if attaching q to p would be an improvement */
-static void try_attach(struct ctl_table_header *p, struct ctl_table_header *q)
+static struct ctl_dir *get_subdir(struct ctl_table_set *set,
+ struct ctl_dir *dir, const char *name, int namelen)
{
- struct ctl_table *to = p->ctl_table, *by = q->ctl_table;
- struct ctl_table *next;
- int is_better = 0;
- int not_in_parent = !p->attached_by;
-
- while ((next = is_branch_in(by, to)) != NULL) {
- if (by == q->attached_by)
- is_better = 1;
- if (to == p->attached_by)
- not_in_parent = 1;
- by = by->child;
- to = next->child;
- }
+ struct ctl_dir *subdir, *new = NULL;
- if (is_better && not_in_parent) {
- q->attached_by = by;
- q->attached_to = to;
- q->parent = p;
+ spin_lock(&sysctl_lock);
+ subdir = find_subdir(dir->header.set, dir, name, namelen);
+ if (!IS_ERR(subdir))
+ goto found;
+ if ((PTR_ERR(subdir) == -ENOENT) && set != dir->header.set)
+ subdir = find_subdir(set, dir, name, namelen);
+ if (!IS_ERR(subdir))
+ goto found;
+ if (PTR_ERR(subdir) != -ENOENT)
+ goto failed;
+
+ spin_unlock(&sysctl_lock);
+ new = new_dir(set, name, namelen);
+ spin_lock(&sysctl_lock);
+ subdir = ERR_PTR(-ENOMEM);
+ if (!new)
+ goto failed;
+
+ subdir = find_subdir(set, dir, name, namelen);
+ if (!IS_ERR(subdir))
+ goto found;
+ if (PTR_ERR(subdir) != -ENOENT)
+ goto failed;
+
+ insert_header(dir, &new->header);
+ subdir = new;
+found:
+ subdir->header.nreg++;
+failed:
+ if (unlikely(IS_ERR(subdir))) {
+ printk(KERN_ERR "sysctl could not get directory: %*.*s %ld\n",
+ namelen, namelen, name, PTR_ERR(subdir));
}
+ drop_sysctl_table(&dir->header);
+ if (new)
+ drop_sysctl_table(&new->header);
+ spin_unlock(&sysctl_lock);
+ return subdir;
}
static int sysctl_check_table_dups(const char *path, struct ctl_table *old,
}
static int sysctl_check_dups(struct nsproxy *namespaces,
- struct ctl_table_header *header,
+ struct ctl_dir *dir,
const char *path, struct ctl_table *table)
{
struct ctl_table_root *root;
struct ctl_table_set *set;
- struct ctl_table_header *dir_head, *head;
- struct ctl_table *dir_table;
+ struct ctl_table_header *head;
int error = 0;
- /* No dups if we are the only member of our directory */
- if (header->attached_by != table)
- return 0;
-
- dir_head = header->parent;
- dir_table = header->attached_to;
-
- error = sysctl_check_table_dups(path, dir_table, table);
-
root = &sysctl_table_root;
do {
set = lookup_header_set(root, namespaces);
list_for_each_entry(head, &set->list, ctl_entry) {
if (head->unregistering)
continue;
- if (head->attached_to != dir_table)
+ if (head->parent != dir)
continue;
- error = sysctl_check_table_dups(path, head->attached_by,
+ error = sysctl_check_table_dups(path, head->ctl_table,
table);
}
root = list_entry(root->root_list.next,
const char *path, struct ctl_table *table)
{
struct ctl_table_header *header;
- struct ctl_table *new, **prevp;
const char *name, *nextname;
- unsigned int npath = 0;
struct ctl_table_set *set;
- size_t path_bytes = 0;
- char *new_name;
-
- /* Count the path components */
- for (name = path; name; name = nextname) {
- int namelen;
- nextname = strchr(name, '/');
- if (nextname) {
- namelen = nextname - name;
- nextname++;
- } else {
- namelen = strlen(name);
- }
- if (namelen == 0)
- continue;
- path_bytes += namelen + 1;
- npath++;
- }
+ struct ctl_dir *dir;
- /*
- * For each path component, allocate a 2-element ctl_table array.
- * The first array element will be filled with the sysctl entry
- * for this, the second will be the sentinel (procname == 0).
- *
- * We allocate everything in one go so that we don't have to
- * worry about freeing additional memory in unregister_sysctl_table.
- */
- header = kzalloc(sizeof(struct ctl_table_header) + path_bytes +
- (2 * npath * sizeof(struct ctl_table)), GFP_KERNEL);
+ header = kzalloc(sizeof(struct ctl_table_header), GFP_KERNEL);
if (!header)
return NULL;
- new = (struct ctl_table *) (header + 1);
- new_name = (char *)(new + (2 * npath));
+ init_header(header, root, NULL, table);
+ if (sysctl_check_table(path, table))
+ goto fail;
+
+ spin_lock(&sysctl_lock);
+ header->set = set = lookup_header_set(root, namespaces);
+ dir = &sysctl_root_dir;
+ dir->header.nreg++;
+ spin_unlock(&sysctl_lock);
- /* Now connect the dots */
- prevp = &header->ctl_table;
+ /* Find the directory for the ctl_table */
for (name = path; name; name = nextname) {
int namelen;
nextname = strchr(name, '/');
}
if (namelen == 0)
continue;
- memcpy(new_name, name, namelen);
- new_name[namelen] = '\0';
-
- new->procname = new_name;
- new->mode = 0555;
-
- *prevp = new;
- prevp = &new->child;
- new += 2;
- new_name += namelen + 1;
+ dir = get_subdir(set, dir, name, namelen);
+ if (IS_ERR(dir))
+ goto fail;
}
- *prevp = table;
-
- init_header(header, root, NULL, table);
- if (sysctl_check_table(path, table))
- goto fail;
-
spin_lock(&sysctl_lock);
- header->set = lookup_header_set(root, namespaces);
- header->attached_by = header->ctl_table;
- header->attached_to = &root_table[1];
- header->parent = &root_table_header;
- set = header->set;
- root = header->root;
- for (;;) {
- struct ctl_table_header *p;
- list_for_each_entry(p, &set->list, ctl_entry) {
- if (p->unregistering)
- continue;
- try_attach(p, header);
- }
- if (root == &sysctl_table_root)
- break;
- root = list_entry(root->root_list.prev,
- struct ctl_table_root, root_list);
- set = lookup_header_set(root, namespaces);
- }
- if (sysctl_check_dups(namespaces, header, path, table))
- goto fail_locked;
- insert_header(header);
+ if (sysctl_check_dups(namespaces, dir, path, table))
+ goto fail_put_dir_locked;
+ insert_header(dir, header);
+ drop_sysctl_table(&dir->header);
spin_unlock(&sysctl_lock);
return header;
-fail_locked:
+fail_put_dir_locked:
+ drop_sysctl_table(&dir->header);
spin_unlock(&sysctl_lock);
fail:
kfree(header);
static void drop_sysctl_table(struct ctl_table_header *header)
{
+ struct ctl_dir *parent = header->parent;
+
if (--header->nreg)
return;
start_unregistering(header);
- if (!--header->parent->count) {
- WARN_ON(1);
- kfree_rcu(header->parent, rcu);
- }
if (!--header->count)
kfree_rcu(header, rcu);
+
+ if (parent)
+ drop_sysctl_table(&parent->header);
}
/**
projects / GitHub / LineageOS / android_kernel_motorola_exynos9610.git / commitdiff