Update Linux to v5.10.109
Sourced from [1]
[1] https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-5.10.109.tar.xz
Change-Id: I19bca9fc6762d4e63bcf3e4cba88bbe560d9c76c
Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>
diff --git a/fs/kernfs/dir.c b/fs/kernfs/dir.c
index 7d4af6c..9aec80b 100644
--- a/fs/kernfs/dir.c
+++ b/fs/kernfs/dir.c
@@ -438,7 +438,7 @@ void kernfs_put_active(struct kernfs_node *kn)
return;
if (kernfs_lockdep(kn))
- rwsem_release(&kn->dep_map, 1, _RET_IP_);
+ rwsem_release(&kn->dep_map, _RET_IP_);
v = atomic_dec_return(&kn->active);
if (likely(v != KN_DEACTIVATED_BIAS))
return;
@@ -476,7 +476,7 @@ static void kernfs_drain(struct kernfs_node *kn)
if (kernfs_lockdep(kn)) {
lock_acquired(&kn->dep_map, _RET_IP_);
- rwsem_release(&kn->dep_map, 1, _RET_IP_);
+ rwsem_release(&kn->dep_map, _RET_IP_);
}
kernfs_drain_open_files(kn);
@@ -508,10 +508,6 @@ void kernfs_put(struct kernfs_node *kn)
struct kernfs_node *parent;
struct kernfs_root *root;
- /*
- * kernfs_node is freed with ->count 0, kernfs_find_and_get_node_by_ino
- * depends on this to filter reused stale node
- */
if (!kn || !atomic_dec_and_test(&kn->count))
return;
root = kernfs_root(kn);
@@ -536,7 +532,7 @@ void kernfs_put(struct kernfs_node *kn)
kmem_cache_free(kernfs_iattrs_cache, kn->iattr);
}
spin_lock(&kernfs_idr_lock);
- idr_remove(&root->ino_idr, kn->id.ino);
+ idr_remove(&root->ino_idr, (u32)kernfs_ino(kn));
spin_unlock(&kernfs_idr_lock);
kmem_cache_free(kernfs_node_cache, kn);
@@ -621,7 +617,7 @@ static struct kernfs_node *__kernfs_new_node(struct kernfs_root *root,
unsigned flags)
{
struct kernfs_node *kn;
- u32 gen;
+ u32 id_highbits;
int ret;
name = kstrdup_const(name, GFP_KERNEL);
@@ -635,22 +631,18 @@ static struct kernfs_node *__kernfs_new_node(struct kernfs_root *root,
idr_preload(GFP_KERNEL);
spin_lock(&kernfs_idr_lock);
ret = idr_alloc_cyclic(&root->ino_idr, kn, 1, 0, GFP_ATOMIC);
- if (ret >= 0 && ret < root->last_ino)
- root->next_generation++;
- gen = root->next_generation;
- root->last_ino = ret;
+ if (ret >= 0 && ret < root->last_id_lowbits)
+ root->id_highbits++;
+ id_highbits = root->id_highbits;
+ root->last_id_lowbits = ret;
spin_unlock(&kernfs_idr_lock);
idr_preload_end();
if (ret < 0)
goto err_out2;
- kn->id.ino = ret;
- kn->id.generation = gen;
- /*
- * set ino first. This RELEASE is paired with atomic_inc_not_zero in
- * kernfs_find_and_get_node_by_ino
- */
- atomic_set_release(&kn->count, 1);
+ kn->id = (u64)id_highbits << 32 | ret;
+
+ atomic_set(&kn->count, 1);
atomic_set(&kn->active, KN_DEACTIVATED_BIAS);
RB_CLEAR_NODE(&kn->rb);
@@ -679,7 +671,7 @@ static struct kernfs_node *__kernfs_new_node(struct kernfs_root *root,
return kn;
err_out3:
- idr_remove(&root->ino_idr, kn->id.ino);
+ idr_remove(&root->ino_idr, (u32)kernfs_ino(kn));
err_out2:
kmem_cache_free(kernfs_node_cache, kn);
err_out1:
@@ -704,50 +696,52 @@ struct kernfs_node *kernfs_new_node(struct kernfs_node *parent,
}
/*
- * kernfs_find_and_get_node_by_ino - get kernfs_node from inode number
+ * kernfs_find_and_get_node_by_id - get kernfs_node from node id
* @root: the kernfs root
- * @ino: inode number
+ * @id: the target node id
+ *
+ * @id's lower 32bits encode ino and upper gen. If the gen portion is
+ * zero, all generations are matched.
*
* RETURNS:
* NULL on failure. Return a kernfs node with reference counter incremented
*/
-struct kernfs_node *kernfs_find_and_get_node_by_ino(struct kernfs_root *root,
- unsigned int ino)
+struct kernfs_node *kernfs_find_and_get_node_by_id(struct kernfs_root *root,
+ u64 id)
{
struct kernfs_node *kn;
+ ino_t ino = kernfs_id_ino(id);
+ u32 gen = kernfs_id_gen(id);
- rcu_read_lock();
- kn = idr_find(&root->ino_idr, ino);
+ spin_lock(&kernfs_idr_lock);
+
+ kn = idr_find(&root->ino_idr, (u32)ino);
if (!kn)
- goto out;
+ goto err_unlock;
- /*
- * Since kernfs_node is freed in RCU, it's possible an old node for ino
- * is freed, but reused before RCU grace period. But a freed node (see
- * kernfs_put) or an incompletedly initialized node (see
- * __kernfs_new_node) should have 'count' 0. We can use this fact to
- * filter out such node.
- */
- if (!atomic_inc_not_zero(&kn->count)) {
- kn = NULL;
- goto out;
+ if (sizeof(ino_t) >= sizeof(u64)) {
+ /* we looked up with the low 32bits, compare the whole */
+ if (kernfs_ino(kn) != ino)
+ goto err_unlock;
+ } else {
+ /* 0 matches all generations */
+ if (unlikely(gen && kernfs_gen(kn) != gen))
+ goto err_unlock;
}
/*
- * The node could be a new node or a reused node. If it's a new node,
- * we are ok. If it's reused because of RCU (because of
- * SLAB_TYPESAFE_BY_RCU), the __kernfs_new_node always sets its 'ino'
- * before 'count'. So if 'count' is uptodate, 'ino' should be uptodate,
- * hence we can use 'ino' to filter stale node.
+ * ACTIVATED is protected with kernfs_mutex but it was clear when
+ * @kn was added to idr and we just wanna see it set. No need to
+ * grab kernfs_mutex.
*/
- if (kn->id.ino != ino)
- goto out;
- rcu_read_unlock();
+ if (unlikely(!(kn->flags & KERNFS_ACTIVATED) ||
+ !atomic_inc_not_zero(&kn->count)))
+ goto err_unlock;
+ spin_unlock(&kernfs_idr_lock);
return kn;
-out:
- rcu_read_unlock();
- kernfs_put(kn);
+err_unlock:
+ spin_unlock(&kernfs_idr_lock);
return NULL;
}
@@ -961,7 +955,17 @@ struct kernfs_root *kernfs_create_root(struct kernfs_syscall_ops *scops,
idr_init(&root->ino_idr);
INIT_LIST_HEAD(&root->supers);
- root->next_generation = 1;
+
+ /*
+ * On 64bit ino setups, id is ino. On 32bit, low 32bits are ino.
+ * High bits generation. The starting value for both ino and
+ * genenration is 1. Initialize upper 32bit allocation
+ * accordingly.
+ */
+ if (sizeof(ino_t) >= sizeof(u64))
+ root->id_highbits = 0;
+ else
+ root->id_highbits = 1;
kn = __kernfs_new_node(root, NULL, "", S_IFDIR | S_IRUGO | S_IXUGO,
GLOBAL_ROOT_UID, GLOBAL_ROOT_GID,
@@ -1262,7 +1266,7 @@ void kernfs_activate(struct kernfs_node *kn)
pos = NULL;
while ((pos = kernfs_next_descendant_post(pos, kn))) {
- if (!pos || (pos->flags & KERNFS_ACTIVATED))
+ if (pos->flags & KERNFS_ACTIVATED)
continue;
WARN_ON_ONCE(pos->parent && RB_EMPTY_NODE(&pos->rb));
@@ -1677,7 +1681,7 @@ static int kernfs_fop_readdir(struct file *file, struct dir_context *ctx)
const char *name = pos->name;
unsigned int type = dt_type(pos);
int len = strlen(name);
- ino_t ino = pos->id.ino;
+ ino_t ino = kernfs_ino(pos);
ctx->pos = pos->hash;
file->private_data = pos;