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Diffstat (limited to 'fs/namespace.c')
-rw-r--r--fs/namespace.c26
1 files changed, 22 insertions, 4 deletions
diff --git a/fs/namespace.c b/fs/namespace.c
index 4a86b859516..3dc283fd471 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -42,6 +42,8 @@ __cacheline_aligned_in_smp DEFINE_SPINLOCK(vfsmount_lock);
static int event;
static DEFINE_IDA(mnt_id_ida);
static DEFINE_IDA(mnt_group_ida);
+static int mnt_id_start = 0;
+static int mnt_group_start = 1;
static struct list_head *mount_hashtable __read_mostly;
static struct kmem_cache *mnt_cache __read_mostly;
@@ -69,7 +71,9 @@ static int mnt_alloc_id(struct vfsmount *mnt)
retry:
ida_pre_get(&mnt_id_ida, GFP_KERNEL);
spin_lock(&vfsmount_lock);
- res = ida_get_new(&mnt_id_ida, &mnt->mnt_id);
+ res = ida_get_new_above(&mnt_id_ida, mnt_id_start, &mnt->mnt_id);
+ if (!res)
+ mnt_id_start = mnt->mnt_id + 1;
spin_unlock(&vfsmount_lock);
if (res == -EAGAIN)
goto retry;
@@ -79,8 +83,11 @@ retry:
static void mnt_free_id(struct vfsmount *mnt)
{
+ int id = mnt->mnt_id;
spin_lock(&vfsmount_lock);
- ida_remove(&mnt_id_ida, mnt->mnt_id);
+ ida_remove(&mnt_id_ida, id);
+ if (mnt_id_start > id)
+ mnt_id_start = id;
spin_unlock(&vfsmount_lock);
}
@@ -91,10 +98,18 @@ static void mnt_free_id(struct vfsmount *mnt)
*/
static int mnt_alloc_group_id(struct vfsmount *mnt)
{
+ int res;
+
if (!ida_pre_get(&mnt_group_ida, GFP_KERNEL))
return -ENOMEM;
- return ida_get_new_above(&mnt_group_ida, 1, &mnt->mnt_group_id);
+ res = ida_get_new_above(&mnt_group_ida,
+ mnt_group_start,
+ &mnt->mnt_group_id);
+ if (!res)
+ mnt_group_start = mnt->mnt_group_id + 1;
+
+ return res;
}
/*
@@ -102,7 +117,10 @@ static int mnt_alloc_group_id(struct vfsmount *mnt)
*/
void mnt_release_group_id(struct vfsmount *mnt)
{
- ida_remove(&mnt_group_ida, mnt->mnt_group_id);
+ int id = mnt->mnt_group_id;
+ ida_remove(&mnt_group_ida, id);
+ if (mnt_group_start > id)
+ mnt_group_start = id;
mnt->mnt_group_id = 0;
}