autofs-5.1.6 - add a hash index to mnt_list

From: Ian Kent <raven@themaw.net>

Add a hash index (and utility functions) to struct mnt_list.

Signed-off-by: Ian Kent <raven@themaw.net>

---

 CHANGELOG        |    1 

 include/mounts.h |    8 +++

 lib/mounts.c     |  135 +++++++++++++++++++++++++++++++++++++++++++++++++++++++

 3 files changed, 144 insertions(+)

--- autofs-5.1.4.orig/CHANGELOG

+++ autofs-5.1.4/CHANGELOG

@@ -121,6 +121,7 @@ xx/xx/2018 autofs-5.1.5

 - change mountpoint to mp in struct ext_mount.

 - make external mounts independent of amd_entry.

 - make external mounts use simpler hashtable.

+- add a hash index to mnt_list.

 19/12/2017 autofs-5.1.4

 - fix spec file url.

--- autofs-5.1.4.orig/include/mounts.h

+++ autofs-5.1.4/include/mounts.h

@@ -54,10 +54,16 @@ struct mapent;

 struct mnt_list {

 	char *mp;

 	unsigned int flags;

+

+	/* Hash of all mounts */

+	struct hlist_node hash;

+	unsigned int ref;

+

 	/*

 	 * List operations ie. get_mnt_list.

 	 */

 	struct mnt_list *next;

+

 	/*

 	 * Tree operations ie. tree_make_tree,

 	 * tree_get_mnt_list etc.

@@ -100,6 +106,8 @@ char *make_mnt_name_string(char *path);

 int ext_mount_add(const char *, const char *);

 int ext_mount_remove(const char *);

 int ext_mount_inuse(const char *);

+struct mnt_list *mnts_lookup_mount(const char *mp);

+void mnts_put_mount(struct mnt_list *mnt);

 struct mnt_list *get_mnt_list(const char *path, int include);

 int unlink_mount_tree(struct autofs_point *ap, const char *mp);

 void free_mnt_list(struct mnt_list *list);

--- autofs-5.1.4.orig/lib/mounts.c

+++ autofs-5.1.4/lib/mounts.c

@@ -63,6 +63,11 @@ struct ext_mount {

 static DEFINE_HASHTABLE(ext_mounts_hash, EXT_MOUNTS_HASH_BITS);

 static pthread_mutex_t ext_mount_hash_mutex = PTHREAD_MUTEX_INITIALIZER;

+#define MNTS_HASH_BITS	7

+

+static DEFINE_HASHTABLE(mnts_hash, MNTS_HASH_BITS);

+static pthread_mutex_t mnts_hash_mutex = PTHREAD_MUTEX_INITIALIZER;

+

 unsigned int linux_version_code(void)

 {

 	struct utsname my_utsname;

@@ -832,6 +837,136 @@ done:

 	return ret;

 }

+static void mnts_hash_mutex_lock(void)

+{

+	int status = pthread_mutex_lock(&mnts_hash_mutex);

+	if (status)

+		fatal(status);

+}

+

+static void mnts_hash_mutex_unlock(void)

+{

+	int status = pthread_mutex_unlock(&mnts_hash_mutex);

+	if (status)

+		fatal(status);

+}

+

+static struct mnt_list *mnts_lookup(const char *mp)

+{

+	uint32_t hval = hash(mp, HASH_SIZE(mnts_hash));

+	struct mnt_list *this;

+

+	if (hlist_empty(&mnts_hash[hval]))

+		return NULL;

+

+	hlist_for_each_entry(this, &mnts_hash[hval], hash) {

+		if (!strcmp(this->mp, mp) && this->ref)

+			return this;

+	}

+

+	return NULL;

+}

+

+static struct mnt_list *mnts_alloc_mount(const char *mp)

+{

+	struct mnt_list *this;

+

+	this = malloc(sizeof(*this));

+	if (!this)

+		goto done;

+	memset(this, 0, sizeof(*this));

+

+	this->mp = strdup(mp);

+	if (!this->mp) {

+		free(this);

+		this = NULL;

+		goto done;

+	}

+

+	this->ref = 1;

+	INIT_HLIST_NODE(&this->hash);

+done:

+	return this;

+}

+

+static void __mnts_get_mount(struct mnt_list *mnt)

+{

+	mnt->ref++;

+}

+

+static void __mnts_put_mount(struct mnt_list *mnt)

+{

+	mnt->ref--;

+	if (!mnt->ref) {

+		hash_del(&mnt->hash);

+		free(mnt->mp);

+		free(mnt);

+	}

+}

+

+static struct mnt_list *mnts_new_mount(const char *mp)

+{

+	struct mnt_list *this;

+

+	this = mnts_lookup(mp);

+	if (this) {

+		__mnts_get_mount(this);

+		goto done;

+	}

+

+	this = mnts_alloc_mount(mp);

+	if (!this)

+		goto done;

+

+	hash_add_str(mnts_hash, &this->hash, this->mp);

+done:

+	return this;

+}

+

+static struct mnt_list *mnts_get_mount(const char *mp)

+{

+	struct mnt_list *this;

+

+	this = mnts_lookup(mp);

+	if (this) {

+		__mnts_get_mount(this);

+		return this;

+	}

+

+	return mnts_new_mount(mp);

+}

+

+static struct mnt_list *__mnts_lookup_mount(const char *mp)

+{

+	struct mnt_list *this;

+

+	this = mnts_lookup(mp);

+	if (this)

+		__mnts_get_mount(this);

+

+	return this;

+}

+

+struct mnt_list *mnts_lookup_mount(const char *mp)

+{

+	struct mnt_list *this;

+

+	mnts_hash_mutex_lock();

+	this = __mnts_lookup_mount(mp);

+	mnts_hash_mutex_unlock();

+

+	return this;

+}

+

+void mnts_put_mount(struct mnt_list *mnt)

+{

+	if (!mnt)

+		return;

+	mnts_hash_mutex_lock();

+	__mnts_put_mount(mnt);

+	mnts_hash_mutex_unlock();

+}

+

 /* From glibc decode_name() */

 /* Since the values in a line are separated by spaces, a name cannot

  * contain a space.  Therefore some programs encode spaces in names