... and the same for vfsmount id/mount group id

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro 2009-06-24 03:12:00 -04:00
parent c63e09eccc
commit f21f62208a
2 changed files with 26 additions and 6 deletions

View File

@ -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 @@ static int mnt_alloc_id(struct vfsmount *mnt)
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;
}

View File

@ -620,7 +620,8 @@ int set_anon_super(struct super_block *s, void *data)
return -ENOMEM;
spin_lock(&unnamed_dev_lock);
error = ida_get_new_above(&unnamed_dev_ida, unnamed_dev_start, &dev);
unnamed_dev_start = dev + 1;
if (!error)
unnamed_dev_start = dev + 1;
spin_unlock(&unnamed_dev_lock);
if (error == -EAGAIN)
/* We raced and lost with another CPU. */
@ -631,7 +632,8 @@ int set_anon_super(struct super_block *s, void *data)
if ((dev & MAX_ID_MASK) == (1 << MINORBITS)) {
spin_lock(&unnamed_dev_lock);
ida_remove(&unnamed_dev_ida, dev);
unnamed_dev_start = dev;
if (unnamed_dev_start > dev)
unnamed_dev_start = dev;
spin_unlock(&unnamed_dev_lock);
return -EMFILE;
}