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-rw-r--r--Documentation/driver-api/driver-model/devres.rst1
-rw-r--r--drivers/base/class.c2
-rw-r--r--drivers/base/core.c2
-rw-r--r--drivers/base/dd.c2
-rw-r--r--drivers/base/devres.c4
-rw-r--r--fs/kernfs/dir.c102
-rw-r--r--fs/kernfs/file.c151
-rw-r--r--fs/kernfs/kernfs-internal.h1
-rw-r--r--include/linux/cgroup.h1
-rw-r--r--include/linux/io.h2
-rw-r--r--include/linux/kernfs.h3
-rw-r--r--kernel/cgroup/cgroup.c20
-rw-r--r--lib/devres.c15
13 files changed, 172 insertions, 134 deletions
diff --git a/Documentation/driver-api/driver-model/devres.rst b/Documentation/driver-api/driver-model/devres.rst
index 55272942e721..2af6c9c09e59 100644
--- a/Documentation/driver-api/driver-model/devres.rst
+++ b/Documentation/driver-api/driver-model/devres.rst
@@ -310,7 +310,6 @@ IOMAP
devm_ioremap()
devm_ioremap_uc()
devm_ioremap_wc()
- devm_ioremap_np()
devm_ioremap_resource() : checks resource, requests memory region, ioremaps
devm_ioremap_resource_wc()
devm_platform_ioremap_resource() : calls devm_ioremap_resource() for platform device
diff --git a/drivers/base/class.c b/drivers/base/class.c
index 8feb85e186e3..64f7b9a0970f 100644
--- a/drivers/base/class.c
+++ b/drivers/base/class.c
@@ -260,7 +260,7 @@ EXPORT_SYMBOL_GPL(__class_create);
*/
void class_destroy(struct class *cls)
{
- if ((cls == NULL) || (IS_ERR(cls)))
+ if (IS_ERR_OR_NULL(cls))
return;
class_unregister(cls);
diff --git a/drivers/base/core.c b/drivers/base/core.c
index 753e7cca0f40..fd0410329046 100644
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -2509,7 +2509,7 @@ static ssize_t uevent_store(struct device *dev, struct device_attribute *attr,
rc = kobject_synth_uevent(&dev->kobj, buf, count);
if (rc) {
- dev_err(dev, "uevent: failed to send synthetic uevent\n");
+ dev_err(dev, "uevent: failed to send synthetic uevent: %d\n", rc);
return rc;
}
diff --git a/drivers/base/dd.c b/drivers/base/dd.c
index ec69b43f926a..3dda62503102 100644
--- a/drivers/base/dd.c
+++ b/drivers/base/dd.c
@@ -836,7 +836,7 @@ static int __init save_async_options(char *buf)
if (strlen(buf) >= ASYNC_DRV_NAMES_MAX_LEN)
pr_warn("Too long list of driver names for 'driver_async_probe'!\n");
- strlcpy(async_probe_drv_names, buf, ASYNC_DRV_NAMES_MAX_LEN);
+ strscpy(async_probe_drv_names, buf, ASYNC_DRV_NAMES_MAX_LEN);
async_probe_default = parse_option_str(async_probe_drv_names, "*");
return 1;
diff --git a/drivers/base/devres.c b/drivers/base/devres.c
index 864d0b3f566e..4ab2b50ee38f 100644
--- a/drivers/base/devres.c
+++ b/drivers/base/devres.c
@@ -117,7 +117,9 @@ static __always_inline struct devres * alloc_dr(dr_release_t release,
if (unlikely(!dr))
return NULL;
- memset(dr, 0, offsetof(struct devres, data));
+ /* No need to clear memory twice */
+ if (!(gfp & __GFP_ZERO))
+ memset(dr, 0, offsetof(struct devres, data));
INIT_LIST_HEAD(&dr->node.entry);
dr->node.release = release;
diff --git a/fs/kernfs/dir.c b/fs/kernfs/dir.c
index 1cc88ba6de90..7fb5a72cc96d 100644
--- a/fs/kernfs/dir.c
+++ b/fs/kernfs/dir.c
@@ -472,6 +472,16 @@ static void kernfs_drain(struct kernfs_node *kn)
lockdep_assert_held_write(&root->kernfs_rwsem);
WARN_ON_ONCE(kernfs_active(kn));
+ /*
+ * Skip draining if already fully drained. This avoids draining and its
+ * lockdep annotations for nodes which have never been activated
+ * allowing embedding kernfs_remove() in create error paths without
+ * worrying about draining.
+ */
+ if (atomic_read(&kn->active) == KN_DEACTIVATED_BIAS &&
+ !kernfs_should_drain_open_files(kn))
+ return;
+
up_write(&root->kernfs_rwsem);
if (kernfs_lockdep(kn)) {
@@ -480,7 +490,6 @@ static void kernfs_drain(struct kernfs_node *kn)
lock_contended(&kn->dep_map, _RET_IP_);
}
- /* but everyone should wait for draining */
wait_event(root->deactivate_waitq,
atomic_read(&kn->active) == KN_DEACTIVATED_BIAS);
@@ -489,7 +498,8 @@ static void kernfs_drain(struct kernfs_node *kn)
rwsem_release(&kn->dep_map, _RET_IP_);
}
- kernfs_drain_open_files(kn);
+ if (kernfs_should_drain_open_files(kn))
+ kernfs_drain_open_files(kn);
down_write(&root->kernfs_rwsem);
}
@@ -695,13 +705,7 @@ struct kernfs_node *kernfs_find_and_get_node_by_id(struct kernfs_root *root,
goto err_unlock;
}
- /*
- * 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 (unlikely(!(kn->flags & KERNFS_ACTIVATED) ||
- !atomic_inc_not_zero(&kn->count)))
+ if (unlikely(!kernfs_active(kn) || !atomic_inc_not_zero(&kn->count)))
goto err_unlock;
spin_unlock(&kernfs_idr_lock);
@@ -743,10 +747,7 @@ int kernfs_add_one(struct kernfs_node *kn)
goto out_unlock;
ret = -ENOENT;
- if (parent->flags & KERNFS_EMPTY_DIR)
- goto out_unlock;
-
- if ((parent->flags & KERNFS_ACTIVATED) && !kernfs_active(parent))
+ if (parent->flags & (KERNFS_REMOVING | KERNFS_EMPTY_DIR))
goto out_unlock;
kn->hash = kernfs_name_hash(kn->name, kn->ns);
@@ -1304,6 +1305,21 @@ static struct kernfs_node *kernfs_next_descendant_post(struct kernfs_node *pos,
return pos->parent;
}
+static void kernfs_activate_one(struct kernfs_node *kn)
+{
+ lockdep_assert_held_write(&kernfs_root(kn)->kernfs_rwsem);
+
+ kn->flags |= KERNFS_ACTIVATED;
+
+ if (kernfs_active(kn) || (kn->flags & (KERNFS_HIDDEN | KERNFS_REMOVING)))
+ return;
+
+ WARN_ON_ONCE(kn->parent && RB_EMPTY_NODE(&kn->rb));
+ WARN_ON_ONCE(atomic_read(&kn->active) != KN_DEACTIVATED_BIAS);
+
+ atomic_sub(KN_DEACTIVATED_BIAS, &kn->active);
+}
+
/**
* kernfs_activate - activate a node which started deactivated
* @kn: kernfs_node whose subtree is to be activated
@@ -1325,15 +1341,42 @@ void kernfs_activate(struct kernfs_node *kn)
down_write(&root->kernfs_rwsem);
pos = NULL;
- while ((pos = kernfs_next_descendant_post(pos, kn))) {
- if (pos->flags & KERNFS_ACTIVATED)
- continue;
+ while ((pos = kernfs_next_descendant_post(pos, kn)))
+ kernfs_activate_one(pos);
+
+ up_write(&root->kernfs_rwsem);
+}
- WARN_ON_ONCE(pos->parent && RB_EMPTY_NODE(&pos->rb));
- WARN_ON_ONCE(atomic_read(&pos->active) != KN_DEACTIVATED_BIAS);
+/**
+ * kernfs_show - show or hide a node
+ * @kn: kernfs_node to show or hide
+ * @show: whether to show or hide
+ *
+ * If @show is %false, @kn is marked hidden and deactivated. A hidden node is
+ * ignored in future activaitons. If %true, the mark is removed and activation
+ * state is restored. This function won't implicitly activate a new node in a
+ * %KERNFS_ROOT_CREATE_DEACTIVATED root which hasn't been activated yet.
+ *
+ * To avoid recursion complexities, directories aren't supported for now.
+ */
+void kernfs_show(struct kernfs_node *kn, bool show)
+{
+ struct kernfs_root *root = kernfs_root(kn);
- atomic_sub(KN_DEACTIVATED_BIAS, &pos->active);
- pos->flags |= KERNFS_ACTIVATED;
+ if (WARN_ON_ONCE(kernfs_type(kn) == KERNFS_DIR))
+ return;
+
+ down_write(&root->kernfs_rwsem);
+
+ if (show) {
+ kn->flags &= ~KERNFS_HIDDEN;
+ if (kn->flags & KERNFS_ACTIVATED)
+ kernfs_activate_one(kn);
+ } else {
+ kn->flags |= KERNFS_HIDDEN;
+ if (kernfs_active(kn))
+ atomic_add(KN_DEACTIVATED_BIAS, &kn->active);
+ kernfs_drain(kn);
}
up_write(&root->kernfs_rwsem);
@@ -1358,34 +1401,27 @@ static void __kernfs_remove(struct kernfs_node *kn)
pr_debug("kernfs %s: removing\n", kn->name);
- /* prevent any new usage under @kn by deactivating all nodes */
+ /* prevent new usage by marking all nodes removing and deactivating */
pos = NULL;
- while ((pos = kernfs_next_descendant_post(pos, kn)))
+ while ((pos = kernfs_next_descendant_post(pos, kn))) {
+ pos->flags |= KERNFS_REMOVING;
if (kernfs_active(pos))
atomic_add(KN_DEACTIVATED_BIAS, &pos->active);
+ }
/* deactivate and unlink the subtree node-by-node */
do {
pos = kernfs_leftmost_descendant(kn);
/*
- * kernfs_drain() drops kernfs_rwsem temporarily and @pos's
+ * kernfs_drain() may drop kernfs_rwsem temporarily and @pos's
* base ref could have been put by someone else by the time
* the function returns. Make sure it doesn't go away
* underneath us.
*/
kernfs_get(pos);
- /*
- * Drain iff @kn was activated. This avoids draining and
- * its lockdep annotations for nodes which have never been
- * activated and allows embedding kernfs_remove() in create
- * error paths without worrying about draining.
- */
- if (kn->flags & KERNFS_ACTIVATED)
- kernfs_drain(pos);
- else
- WARN_ON_ONCE(atomic_read(&kn->active) != KN_DEACTIVATED_BIAS);
+ kernfs_drain(pos);
/*
* kernfs_unlink_sibling() succeeds once per node. Use it
diff --git a/fs/kernfs/file.c b/fs/kernfs/file.c
index b3ec34386b43..9ab6c92e02da 100644
--- a/fs/kernfs/file.c
+++ b/fs/kernfs/file.c
@@ -23,6 +23,8 @@ struct kernfs_open_node {
atomic_t event;
wait_queue_head_t poll;
struct list_head files; /* goes through kernfs_open_file.list */
+ unsigned int nr_mmapped;
+ unsigned int nr_to_release;
};
/*
@@ -57,31 +59,17 @@ static inline struct mutex *kernfs_open_file_mutex_lock(struct kernfs_node *kn)
}
/**
- * kernfs_deref_open_node - Get kernfs_open_node corresponding to @kn.
- *
- * @of: associated kernfs_open_file instance.
- * @kn: target kernfs_node.
- *
- * Fetch and return ->attr.open of @kn if @of->list is non empty.
- * If @of->list is not empty we can safely assume that @of is on
- * @kn->attr.open->files list and this guarantees that @kn->attr.open
- * will not vanish i.e. dereferencing outside RCU read-side critical
- * section is safe here.
- *
- * The caller needs to make sure that @of->list is not empty.
+ * of_on - Return the kernfs_open_node of the specified kernfs_open_file
+ * @of: taret kernfs_open_file
*/
-static struct kernfs_open_node *
-kernfs_deref_open_node(struct kernfs_open_file *of, struct kernfs_node *kn)
+static struct kernfs_open_node *of_on(struct kernfs_open_file *of)
{
- struct kernfs_open_node *on;
-
- on = rcu_dereference_check(kn->attr.open, !list_empty(&of->list));
-
- return on;
+ return rcu_dereference_protected(of->kn->attr.open,
+ !list_empty(&of->list));
}
/**
- * kernfs_deref_open_node_protected - Get kernfs_open_node corresponding to @kn
+ * kernfs_deref_open_node_locked - Get kernfs_open_node corresponding to @kn
*
* @kn: target kernfs_node.
*
@@ -96,7 +84,7 @@ kernfs_deref_open_node(struct kernfs_open_file *of, struct kernfs_node *kn)
* The caller needs to make sure that kernfs_open_file_mutex is held.
*/
static struct kernfs_open_node *
-kernfs_deref_open_node_protected(struct kernfs_node *kn)
+kernfs_deref_open_node_locked(struct kernfs_node *kn)
{
return rcu_dereference_protected(kn->attr.open,
lockdep_is_held(kernfs_open_file_mutex_ptr(kn)));
@@ -207,12 +195,8 @@ static void kernfs_seq_stop(struct seq_file *sf, void *v)
static int kernfs_seq_show(struct seq_file *sf, void *v)
{
struct kernfs_open_file *of = sf->private;
- struct kernfs_open_node *on = kernfs_deref_open_node(of, of->kn);
-
- if (!on)
- return -EINVAL;
- of->event = atomic_read(&on->event);
+ of->event = atomic_read(&of_on(of)->event);
return of->kn->attr.ops->seq_show(sf, v);
}
@@ -235,7 +219,6 @@ static ssize_t kernfs_file_read_iter(struct kiocb *iocb, struct iov_iter *iter)
struct kernfs_open_file *of = kernfs_of(iocb->ki_filp);
ssize_t len = min_t(size_t, iov_iter_count(iter), PAGE_SIZE);
const struct kernfs_ops *ops;
- struct kernfs_open_node *on;
char *buf;
buf = of->prealloc_buf;
@@ -257,14 +240,7 @@ static ssize_t kernfs_file_read_iter(struct kiocb *iocb, struct iov_iter *iter)
goto out_free;
}
- on = kernfs_deref_open_node(of, of->kn);
- if (!on) {
- len = -EINVAL;
- mutex_unlock(&of->mutex);
- goto out_free;
- }
-
- of->event = atomic_read(&on->event);
+ of->event = atomic_read(&of_on(of)->event);
ops = kernfs_ops(of->kn);
if (ops->read)
@@ -553,6 +529,7 @@ static int kernfs_fop_mmap(struct file *file, struct vm_area_struct *vma)
rc = 0;
of->mmapped = true;
+ of_on(of)->nr_mmapped++;
of->vm_ops = vma->vm_ops;
vma->vm_ops = &kernfs_vm_ops;
out_put:
@@ -580,31 +557,30 @@ out_unlock:
static int kernfs_get_open_node(struct kernfs_node *kn,
struct kernfs_open_file *of)
{
- struct kernfs_open_node *on, *new_on = NULL;
- struct mutex *mutex = NULL;
+ struct kernfs_open_node *on;
+ struct mutex *mutex;
mutex = kernfs_open_file_mutex_lock(kn);
- on = kernfs_deref_open_node_protected(kn);
+ on = kernfs_deref_open_node_locked(kn);
- if (on) {
- list_add_tail(&of->list, &on->files);
- mutex_unlock(mutex);
- return 0;
- } else {
+ if (!on) {
/* not there, initialize a new one */
- new_on = kmalloc(sizeof(*new_on), GFP_KERNEL);
- if (!new_on) {
+ on = kzalloc(sizeof(*on), GFP_KERNEL);
+ if (!on) {
mutex_unlock(mutex);
return -ENOMEM;
}
- atomic_set(&new_on->event, 1);
- init_waitqueue_head(&new_on->poll);
- INIT_LIST_HEAD(&new_on->files);
- list_add_tail(&of->list, &new_on->files);
- rcu_assign_pointer(kn->attr.open, new_on);
+ atomic_set(&on->event, 1);
+ init_waitqueue_head(&on->poll);
+ INIT_LIST_HEAD(&on->files);
+ rcu_assign_pointer(kn->attr.open, on);
}
- mutex_unlock(mutex);
+ list_add_tail(&of->list, &on->files);
+ if (kn->flags & KERNFS_HAS_RELEASE)
+ on->nr_to_release++;
+
+ mutex_unlock(mutex);
return 0;
}
@@ -613,6 +589,7 @@ static int kernfs_get_open_node(struct kernfs_node *kn,
*
* @kn: target kernfs_node
* @of: associated kernfs_open_file
+ * @open_failed: ->open() failed, cancel ->release()
*
* Unlink @of from list of @kn's associated open files. If list of
* associated open files becomes empty, disassociate and free
@@ -622,21 +599,30 @@ static int kernfs_get_open_node(struct kernfs_node *kn,
* None.
*/
static void kernfs_unlink_open_file(struct kernfs_node *kn,
- struct kernfs_open_file *of)
+ struct kernfs_open_file *of,
+ bool open_failed)
{
struct kernfs_open_node *on;
- struct mutex *mutex = NULL;
+ struct mutex *mutex;
mutex = kernfs_open_file_mutex_lock(kn);
- on = kernfs_deref_open_node_protected(kn);
+ on = kernfs_deref_open_node_locked(kn);
if (!on) {
mutex_unlock(mutex);
return;
}
- if (of)
+ if (of) {
+ if (kn->flags & KERNFS_HAS_RELEASE) {
+ WARN_ON_ONCE(of->released == open_failed);
+ if (open_failed)
+ on->nr_to_release--;
+ }
+ if (of->mmapped)
+ on->nr_mmapped--;
list_del(&of->list);
+ }
if (list_empty(&on->files)) {
rcu_assign_pointer(kn->attr.open, NULL);
@@ -763,7 +749,7 @@ static int kernfs_fop_open(struct inode *inode, struct file *file)
return 0;
err_put_node:
- kernfs_unlink_open_file(kn, of);
+ kernfs_unlink_open_file(kn, of, true);
err_seq_release:
seq_release(inode, file);
err_free:
@@ -795,6 +781,7 @@ static void kernfs_release_file(struct kernfs_node *kn,
*/
kn->attr.ops->release(of);
of->released = true;
+ of_on(of)->nr_to_release--;
}
}
@@ -802,15 +789,16 @@ static int kernfs_fop_release(struct inode *inode, struct file *filp)
{
struct kernfs_node *kn = inode->i_private;
struct kernfs_open_file *of = kernfs_of(filp);
- struct mutex *mutex = NULL;
if (kn->flags & KERNFS_HAS_RELEASE) {
+ struct mutex *mutex;
+
mutex = kernfs_open_file_mutex_lock(kn);
kernfs_release_file(kn, of);
mutex_unlock(mutex);
}
- kernfs_unlink_open_file(kn, of);
+ kernfs_unlink_open_file(kn, of, false);
seq_release(inode, filp);
kfree(of->prealloc_buf);
kfree(of);
@@ -818,28 +806,33 @@ static int kernfs_fop_release(struct inode *inode, struct file *filp)
return 0;
}
-void kernfs_drain_open_files(struct kernfs_node *kn)
+bool kernfs_should_drain_open_files(struct kernfs_node *kn)
{
struct kernfs_open_node *on;
- struct kernfs_open_file *of;
- struct mutex *mutex = NULL;
-
- if (!(kn->flags & (KERNFS_HAS_MMAP | KERNFS_HAS_RELEASE)))
- return;
+ bool ret;
/*
- * lockless opportunistic check is safe below because no one is adding to
- * ->attr.open at this point of time. This check allows early bail out
- * if ->attr.open is already NULL. kernfs_unlink_open_file makes
- * ->attr.open NULL only while holding kernfs_open_file_mutex so below
- * check under kernfs_open_file_mutex_ptr(kn) will ensure bailing out if
- * ->attr.open became NULL while waiting for the mutex.
+ * @kn being deactivated guarantees that @kn->attr.open can't change
+ * beneath us making the lockless test below safe.
*/
- if (!rcu_access_pointer(kn->attr.open))
- return;
+ WARN_ON_ONCE(atomic_read(&kn->active) != KN_DEACTIVATED_BIAS);
+
+ rcu_read_lock();
+ on = rcu_dereference(kn->attr.open);
+ ret = on && (on->nr_mmapped || on->nr_to_release);
+ rcu_read_unlock();
+
+ return ret;
+}
+
+void kernfs_drain_open_files(struct kernfs_node *kn)
+{
+ struct kernfs_open_node *on;
+ struct kernfs_open_file *of;
+ struct mutex *mutex;
mutex = kernfs_open_file_mutex_lock(kn);
- on = kernfs_deref_open_node_protected(kn);
+ on = kernfs_deref_open_node_locked(kn);
if (!on) {
mutex_unlock(mutex);
return;
@@ -848,13 +841,17 @@ void kernfs_drain_open_files(struct kernfs_node *kn)
list_for_each_entry(of, &on->files, list) {
struct inode *inode = file_inode(of->file);
- if (kn->flags & KERNFS_HAS_MMAP)
+ if (of->mmapped) {
unmap_mapping_range(inode->i_mapping, 0, 0, 1);
+ of->mmapped = false;
+ on->nr_mmapped--;
+ }
if (kn->flags & KERNFS_HAS_RELEASE)
kernfs_release_file(kn, of);
}
+ WARN_ON_ONCE(on->nr_mmapped || on->nr_to_release);
mutex_unlock(mutex);
}
@@ -874,11 +871,7 @@ void kernfs_drain_open_files(struct kernfs_node *kn)
*/
__poll_t kernfs_generic_poll(struct kernfs_open_file *of, poll_table *wait)
{
- struct kernfs_node *kn = kernfs_dentry_node(of->file->f_path.dentry);
- struct kernfs_open_node *on = kernfs_deref_open_node(of, kn);
-
- if (!on)
- return EPOLLERR;
+ struct kernfs_open_node *on = of_on(of);
poll_wait(of->file, &on->poll, wait);
diff --git a/fs/kernfs/kernfs-internal.h b/fs/kernfs/kernfs-internal.h
index 3ae214d02d44..fc5821effd97 100644
--- a/fs/kernfs/kernfs-internal.h
+++ b/fs/kernfs/kernfs-internal.h
@@ -157,6 +157,7 @@ struct kernfs_node *kernfs_new_node(struct kernfs_node *parent,
*/
extern const struct file_operations kernfs_file_fops;
+bool kernfs_should_drain_open_files(struct kernfs_node *kn);
void kernfs_drain_open_files(struct kernfs_node *kn);
/*
diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h
index ac5d0515680e..b0914aa26506 100644
--- a/include/linux/cgroup.h
+++ b/include/linux/cgroup.h
@@ -114,6 +114,7 @@ int cgroup_add_dfl_cftypes(struct cgroup_subsys *ss, struct cftype *cfts);
int cgroup_add_legacy_cftypes(struct cgroup_subsys *ss, struct cftype *cfts);
int cgroup_rm_cftypes(struct cftype *cfts);
void cgroup_file_notify(struct cgroup_file *cfile);
+void cgroup_file_show(struct cgroup_file *cfile, bool show);
int task_cgroup_path(struct task_struct *task, char *buf, size_t buflen);
int cgroupstats_build(struct cgroupstats *stats, struct dentry *dentry);
diff --git a/include/linux/io.h b/include/linux/io.h
index 5fc800390fe4..308f4f0cfb93 100644
--- a/include/linux/io.h
+++ b/include/linux/io.h
@@ -59,8 +59,6 @@ void __iomem *devm_ioremap_uc(struct device *dev, resource_size_t offset,
resource_size_t size);
void __iomem *devm_ioremap_wc(struct device *dev, resource_size_t offset,
resource_size_t size);
-void __iomem *devm_ioremap_np(struct device *dev, resource_size_t offset,
- resource_size_t size);
void devm_iounmap(struct device *dev, void __iomem *addr);
int check_signature(const volatile void __iomem *io_addr,
const unsigned char *signature, int length);
diff --git a/include/linux/kernfs.h b/include/linux/kernfs.h
index 367044d7708c..73f5c120def8 100644
--- a/include/linux/kernfs.h
+++ b/include/linux/kernfs.h
@@ -108,10 +108,12 @@ enum kernfs_node_flag {
KERNFS_HAS_SEQ_SHOW = 0x0040,
KERNFS_HAS_MMAP = 0x0080,
KERNFS_LOCKDEP = 0x0100,
+ KERNFS_HIDDEN = 0x0200,
KERNFS_SUICIDAL = 0x0400,
KERNFS_SUICIDED = 0x0800,
KERNFS_EMPTY_DIR = 0x1000,
KERNFS_HAS_RELEASE = 0x2000,
+ KERNFS_REMOVING = 0x4000,
};
/* @flags for kernfs_create_root() */
@@ -429,6 +431,7 @@ struct kernfs_node *kernfs_create_link(struct kernfs_node *parent,
const char *name,
struct kernfs_node *target);
void kernfs_activate(struct kernfs_node *kn);
+void kernfs_show(struct kernfs_node *kn, bool show);
void kernfs_remove(struct kernfs_node *kn);
void kernfs_break_active_protection(struct kernfs_node *kn);
void kernfs_unbreak_active_protection(struct kernfs_node *kn);
diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c
index e4bb5d57f4d1..718a70c01c04 100644
--- a/kernel/cgroup/cgroup.c
+++ b/kernel/cgroup/cgroup.c
@@ -4372,6 +4372,26 @@ void cgroup_file_notify(struct cgroup_file *cfile)
}
/**
+ * cgroup_file_show - show or hide a hidden cgroup file
+ * @cfile: target cgroup_file obtained by setting cftype->file_offset
+ * @show: whether to show or hide
+ */
+void cgroup_file_show(struct cgroup_file *cfile, bool show)
+{
+ struct kernfs_node *kn;
+
+ spin_lock_irq(&cgroup_file_kn_lock);
+ kn = cfile->kn;
+ kernfs_get(kn);
+ spin_unlock_irq(&cgroup_file_kn_lock);
+
+ if (kn)
+ kernfs_show(kn, show);
+
+ kernfs_put(kn);
+}
+
+/**
* css_next_child - find the next child of a given css
* @pos: the current position (%NULL to initiate traversal)
* @parent: css whose children to walk
diff --git a/lib/devres.c b/lib/devres.c
index 55eb07e80cbb..6baf43902ead 100644
--- a/lib/devres.c
+++ b/lib/devres.c
@@ -104,21 +104,6 @@ void __iomem *devm_ioremap_wc(struct device *dev, resource_size_t offset,
EXPORT_SYMBOL(devm_ioremap_wc);
/**
- * devm_ioremap_np - Managed ioremap_np()
- * @dev: Generic device to remap IO address for
- * @offset: Resource address to map
- * @size: Size of map
- *
- * Managed ioremap_np(). Map is automatically unmapped on driver detach.
- */
-void __iomem *devm_ioremap_np(struct device *dev, resource_size_t offset,
- resource_size_t size)
-{
- return __devm_ioremap(dev, offset, size, DEVM_IOREMAP_NP);
-}
-EXPORT_SYMBOL(devm_ioremap_np);
-
-/**
* devm_iounmap - Managed iounmap()
* @dev: Generic device to unmap for
* @addr: Address to unmap