[PATCH 24/37] binder: refactor binder ref inc/dec for thread safety

From: Todd Kjos
Date: Thu Jun 29 2017 - 15:06:38 EST


Once locks are added, binder_ref's will only be accessed
safely with the proc lock held. Refactor the inc/dec paths
to make them atomic with the binder_get_ref* paths and
node inc/dec. For example, instead of:

ref = binder_get_ref(proc, handle, strong);
...
binder_dec_ref(ref, strong);

we now have:

ret = binder_dec_ref_for_handle(proc, handle, strong, &rdata);

Since the actual ref is no longer exposed to callers, a
new struct binder_ref_data is introduced which can be used
to return a copy of ref state.

Signed-off-by: Todd Kjos <tkjos@xxxxxxxxxx>
---
drivers/android/binder.c | 484 ++++++++++++++++++++++++++++++-----------
drivers/android/binder_trace.h | 32 +--
2 files changed, 379 insertions(+), 137 deletions(-)

diff --git a/drivers/android/binder.c b/drivers/android/binder.c
index ca7d866b89e8..4d0b99862339 100644
--- a/drivers/android/binder.c
+++ b/drivers/android/binder.c
@@ -291,20 +291,51 @@ struct binder_ref_death {
binder_uintptr_t cookie;
};

+/**
+ * struct binder_ref_data - binder_ref counts and id
+ * @debug_id: unique ID for the ref
+ * @desc: unique userspace handle for ref
+ * @strong: strong ref count (debugging only if not locked)
+ * @weak: weak ref count (debugging only if not locked)
+ *
+ * Structure to hold ref count and ref id information. Since
+ * the actual ref can only be accessed with a lock, this structure
+ * is used to return information about the ref to callers of
+ * ref inc/dec functions.
+ */
+struct binder_ref_data {
+ int debug_id;
+ uint32_t desc;
+ int strong;
+ int weak;
+};
+
+/**
+ * struct binder_ref - struct to track references on nodes
+ * @data: binder_ref_data containing id, handle, and current refcounts
+ * @rb_node_desc: node for lookup by @data.desc in proc's rb_tree
+ * @rb_node_node: node for lookup by @node in proc's rb_tree
+ * @node_entry: list entry for node->refs list in target node
+ * @proc: binder_proc containing ref
+ * @node: binder_node of target node. When cleaning up a
+ * ref for deletion in binder_cleanup_ref, a non-NULL
+ * @node indicates the node must be freed
+ * @death: pointer to death notification (ref_death) if requested
+ *
+ * Structure to track references from procA to target node (on procB). This
+ * structure is unsafe to access without holding @proc->outer_lock.
+ */
struct binder_ref {
/* Lookups needed: */
/* node + proc => ref (transaction) */
/* desc + proc => ref (transaction, inc/dec ref) */
/* node => refs + procs (proc exit) */
- int debug_id;
+ struct binder_ref_data data;
struct rb_node rb_node_desc;
struct rb_node rb_node_node;
struct hlist_node node_entry;
struct binder_proc *proc;
struct binder_node *node;
- uint32_t desc;
- int strong;
- int weak;
struct binder_ref_death *death;
};

@@ -627,11 +658,11 @@ static struct binder_ref *binder_get_ref(struct binder_proc *proc,
while (n) {
ref = rb_entry(n, struct binder_ref, rb_node_desc);

- if (desc < ref->desc) {
+ if (desc < ref->data.desc) {
n = n->rb_left;
- } else if (desc > ref->desc) {
+ } else if (desc > ref->data.desc) {
n = n->rb_right;
- } else if (need_strong_ref && !ref->strong) {
+ } else if (need_strong_ref && !ref->data.strong) {
binder_user_error("tried to use weak ref as strong ref\n");
return NULL;
} else {
@@ -641,14 +672,33 @@ static struct binder_ref *binder_get_ref(struct binder_proc *proc,
return NULL;
}

+/**
+ * binder_get_ref_for_node() - get the ref associated with given node
+ * @proc: binder_proc that owns the ref
+ * @node: binder_node of target
+ * @new_ref: newly allocated binder_ref to be initialized or %NULL
+ *
+ * Look up the ref for the given node and return it if it exists
+ *
+ * If it doesn't exist and the caller provides a newly allocated
+ * ref, initialize the fields of the newly allocated ref and insert
+ * into the given proc rb_trees and node refs list.
+ *
+ * Return: the ref for node. It is possible that another thread
+ * allocated/initialized the ref first in which case the
+ * returned ref would be different than the passed-in
+ * new_ref. new_ref must be kfree'd by the caller in
+ * this case.
+ */
static struct binder_ref *binder_get_ref_for_node(struct binder_proc *proc,
- struct binder_node *node)
+ struct binder_node *node,
+ struct binder_ref *new_ref)
{
- struct rb_node *n;
+ struct binder_context *context = proc->context;
struct rb_node **p = &proc->refs_by_node.rb_node;
struct rb_node *parent = NULL;
- struct binder_ref *ref, *new_ref;
- struct binder_context *context = proc->context;
+ struct binder_ref *ref;
+ struct rb_node *n;

while (*p) {
parent = *p;
@@ -661,22 +711,22 @@ static struct binder_ref *binder_get_ref_for_node(struct binder_proc *proc,
else
return ref;
}
- new_ref = kzalloc(sizeof(*ref), GFP_KERNEL);
- if (new_ref == NULL)
+ if (!new_ref)
return NULL;
+
binder_stats_created(BINDER_STAT_REF);
- new_ref->debug_id = atomic_inc_return(&binder_last_id);
+ new_ref->data.debug_id = atomic_inc_return(&binder_last_id);
new_ref->proc = proc;
new_ref->node = node;
rb_link_node(&new_ref->rb_node_node, parent, p);
rb_insert_color(&new_ref->rb_node_node, &proc->refs_by_node);

- new_ref->desc = (node == context->binder_context_mgr_node) ? 0 : 1;
+ new_ref->data.desc = (node == context->binder_context_mgr_node) ? 0 : 1;
for (n = rb_first(&proc->refs_by_desc); n != NULL; n = rb_next(n)) {
ref = rb_entry(n, struct binder_ref, rb_node_desc);
- if (ref->desc > new_ref->desc)
+ if (ref->data.desc > new_ref->data.desc)
break;
- new_ref->desc = ref->desc + 1;
+ new_ref->data.desc = ref->data.desc + 1;
}

p = &proc->refs_by_desc.rb_node;
@@ -684,9 +734,9 @@ static struct binder_ref *binder_get_ref_for_node(struct binder_proc *proc,
parent = *p;
ref = rb_entry(parent, struct binder_ref, rb_node_desc);

- if (new_ref->desc < ref->desc)
+ if (new_ref->data.desc < ref->data.desc)
p = &(*p)->rb_left;
- else if (new_ref->desc > ref->desc)
+ else if (new_ref->data.desc > ref->data.desc)
p = &(*p)->rb_right;
else
BUG();
@@ -697,89 +747,267 @@ static struct binder_ref *binder_get_ref_for_node(struct binder_proc *proc,

binder_debug(BINDER_DEBUG_INTERNAL_REFS,
"%d new ref %d desc %d for node %d\n",
- proc->pid, new_ref->debug_id, new_ref->desc,
+ proc->pid, new_ref->data.debug_id, new_ref->data.desc,
node->debug_id);
return new_ref;
}

-static void binder_delete_ref(struct binder_ref *ref)
+static void binder_cleanup_ref(struct binder_ref *ref)
{
binder_debug(BINDER_DEBUG_INTERNAL_REFS,
"%d delete ref %d desc %d for node %d\n",
- ref->proc->pid, ref->debug_id, ref->desc,
+ ref->proc->pid, ref->data.debug_id, ref->data.desc,
ref->node->debug_id);

rb_erase(&ref->rb_node_desc, &ref->proc->refs_by_desc);
rb_erase(&ref->rb_node_node, &ref->proc->refs_by_node);
- if (ref->strong)
+
+ if (ref->data.strong)
binder_dec_node(ref->node, 1, 1);
+
hlist_del(&ref->node_entry);
binder_dec_node(ref->node, 0, 1);
+
if (ref->death) {
binder_debug(BINDER_DEBUG_DEAD_BINDER,
"%d delete ref %d desc %d has death notification\n",
- ref->proc->pid, ref->debug_id, ref->desc);
+ ref->proc->pid, ref->data.debug_id,
+ ref->data.desc);
list_del(&ref->death->work.entry);
- kfree(ref->death);
binder_stats_deleted(BINDER_STAT_DEATH);
}
- kfree(ref);
binder_stats_deleted(BINDER_STAT_REF);
}

+/**
+ * binder_inc_ref() - increment the ref for given handle
+ * @ref: ref to be incremented
+ * @strong: if true, strong increment, else weak
+ * @target_list: list to queue node work on
+ *
+ * Increment the ref.
+ *
+ * Return: 0, if successful, else errno
+ */
static int binder_inc_ref(struct binder_ref *ref, int strong,
struct list_head *target_list)
{
int ret;

if (strong) {
- if (ref->strong == 0) {
+ if (ref->data.strong == 0) {
ret = binder_inc_node(ref->node, 1, 1, target_list);
if (ret)
return ret;
}
- ref->strong++;
+ ref->data.strong++;
} else {
- if (ref->weak == 0) {
+ if (ref->data.weak == 0) {
ret = binder_inc_node(ref->node, 0, 1, target_list);
if (ret)
return ret;
}
- ref->weak++;
+ ref->data.weak++;
}
return 0;
}

-
-static int binder_dec_ref(struct binder_ref *ref, int strong)
+/**
+ * binder_dec_ref() - dec the ref for given handle
+ * @ref: ref to be decremented
+ * @strong: if true, strong decrement, else weak
+ *
+ * Decrement the ref.
+ *
+ * TODO: kfree is avoided here since an upcoming patch
+ * will put this under a lock.
+ *
+ * Return: true if ref is cleaned up and ready to be freed
+ */
+static bool binder_dec_ref(struct binder_ref *ref, int strong)
{
if (strong) {
- if (ref->strong == 0) {
+ if (ref->data.strong == 0) {
binder_user_error("%d invalid dec strong, ref %d desc %d s %d w %d\n",
- ref->proc->pid, ref->debug_id,
- ref->desc, ref->strong, ref->weak);
- return -EINVAL;
+ ref->proc->pid, ref->data.debug_id,
+ ref->data.desc, ref->data.strong,
+ ref->data.weak);
+ return false;
}
- ref->strong--;
- if (ref->strong == 0) {
+ ref->data.strong--;
+ if (ref->data.strong == 0) {
int ret;

ret = binder_dec_node(ref->node, strong, 1);
if (ret)
- return ret;
+ return false;
}
} else {
- if (ref->weak == 0) {
+ if (ref->data.weak == 0) {
binder_user_error("%d invalid dec weak, ref %d desc %d s %d w %d\n",
- ref->proc->pid, ref->debug_id,
- ref->desc, ref->strong, ref->weak);
- return -EINVAL;
+ ref->proc->pid, ref->data.debug_id,
+ ref->data.desc, ref->data.strong,
+ ref->data.weak);
+ return false;
}
- ref->weak--;
+ ref->data.weak--;
}
- if (ref->strong == 0 && ref->weak == 0)
- binder_delete_ref(ref);
- return 0;
+ if (ref->data.strong == 0 && ref->data.weak == 0) {
+ binder_cleanup_ref(ref);
+ /*
+ * TODO: we could kfree(ref) here, but an upcoming
+ * patch will call this with a lock held, so we
+ * return an indication that the ref should be
+ * freed.
+ */
+ return true;
+ }
+ return false;
+}
+
+/**
+ * binder_get_node_from_ref() - get the node from the given proc/desc
+ * @proc: proc containing the ref
+ * @desc: the handle associated with the ref
+ * @need_strong_ref: if true, only return node if ref is strong
+ * @rdata: the id/refcount data for the ref
+ *
+ * Given a proc and ref handle, return the associated binder_node
+ *
+ * Return: a binder_node or NULL if not found or not strong when strong required
+ */
+static struct binder_node *binder_get_node_from_ref(
+ struct binder_proc *proc,
+ u32 desc, bool need_strong_ref,
+ struct binder_ref_data *rdata)
+{
+ struct binder_node *node;
+ struct binder_ref *ref;
+
+ ref = binder_get_ref(proc, desc, need_strong_ref);
+ if (!ref)
+ goto err_no_ref;
+ node = ref->node;
+ if (rdata)
+ *rdata = ref->data;
+
+ return node;
+
+err_no_ref:
+ return NULL;
+}
+
+/**
+ * binder_free_ref() - free the binder_ref
+ * @ref: ref to free
+ *
+ * Free the binder_ref and the binder_ref_death indicated by ref->death.
+ */
+static void binder_free_ref(struct binder_ref *ref)
+{
+ kfree(ref->death);
+ kfree(ref);
+}
+
+/**
+ * binder_update_ref_for_handle() - inc/dec the ref for given handle
+ * @proc: proc containing the ref
+ * @desc: the handle associated with the ref
+ * @increment: true=inc reference, false=dec reference
+ * @strong: true=strong reference, false=weak reference
+ * @rdata: the id/refcount data for the ref
+ *
+ * Given a proc and ref handle, increment or decrement the ref
+ * according to "increment" arg.
+ *
+ * Return: 0 if successful, else errno
+ */
+static int binder_update_ref_for_handle(struct binder_proc *proc,
+ uint32_t desc, bool increment, bool strong,
+ struct binder_ref_data *rdata)
+{
+ int ret = 0;
+ struct binder_ref *ref;
+ bool delete_ref = false;
+
+ ref = binder_get_ref(proc, desc, strong);
+ if (!ref) {
+ ret = -EINVAL;
+ goto err_no_ref;
+ }
+ if (increment)
+ ret = binder_inc_ref(ref, strong, NULL);
+ else
+ delete_ref = binder_dec_ref(ref, strong);
+
+ if (rdata)
+ *rdata = ref->data;
+
+ if (delete_ref)
+ binder_free_ref(ref);
+ return ret;
+
+err_no_ref:
+ return ret;
+}
+
+/**
+ * binder_dec_ref_for_handle() - dec the ref for given handle
+ * @proc: proc containing the ref
+ * @desc: the handle associated with the ref
+ * @strong: true=strong reference, false=weak reference
+ * @rdata: the id/refcount data for the ref
+ *
+ * Just calls binder_update_ref_for_handle() to decrement the ref.
+ *
+ * Return: 0 if successful, else errno
+ */
+static int binder_dec_ref_for_handle(struct binder_proc *proc,
+ uint32_t desc, bool strong, struct binder_ref_data *rdata)
+{
+ return binder_update_ref_for_handle(proc, desc, false, strong, rdata);
+}
+
+
+/**
+ * binder_inc_ref_for_node() - increment the ref for given proc/node
+ * @proc: proc containing the ref
+ * @node: target node
+ * @strong: true=strong reference, false=weak reference
+ * @target_list: worklist to use if node is incremented
+ * @rdata: the id/refcount data for the ref
+ *
+ * Given a proc and node, increment the ref. Create the ref if it
+ * doesn't already exist
+ *
+ * Return: 0 if successful, else errno
+ */
+static int binder_inc_ref_for_node(struct binder_proc *proc,
+ struct binder_node *node,
+ bool strong,
+ struct list_head *target_list,
+ struct binder_ref_data *rdata)
+{
+ struct binder_ref *ref;
+ struct binder_ref *new_ref = NULL;
+ int ret = 0;
+
+ ref = binder_get_ref_for_node(proc, node, NULL);
+ if (!ref) {
+ new_ref = kzalloc(sizeof(*ref), GFP_KERNEL);
+ if (!new_ref)
+ return -ENOMEM;
+ ref = binder_get_ref_for_node(proc, node, new_ref);
+ }
+ ret = binder_inc_ref(ref, strong, target_list);
+ *rdata = ref->data;
+ if (new_ref && ref != new_ref)
+ /*
+ * Another thread created the ref first so
+ * free the one we allocated
+ */
+ kfree(new_ref);
+ return ret;
}

static void binder_pop_transaction(struct binder_thread *target_thread,
@@ -1124,20 +1352,21 @@ static void binder_transaction_buffer_release(struct binder_proc *proc,
case BINDER_TYPE_HANDLE:
case BINDER_TYPE_WEAK_HANDLE: {
struct flat_binder_object *fp;
- struct binder_ref *ref;
+ struct binder_ref_data rdata;
+ int ret;

fp = to_flat_binder_object(hdr);
- ref = binder_get_ref(proc, fp->handle,
- hdr->type == BINDER_TYPE_HANDLE);
- if (ref == NULL) {
- pr_err("transaction release %d bad handle %d\n",
- debug_id, fp->handle);
+ ret = binder_dec_ref_for_handle(proc, fp->handle,
+ hdr->type == BINDER_TYPE_HANDLE, &rdata);
+
+ if (ret) {
+ pr_err("transaction release %d bad handle %d, ret = %d\n",
+ debug_id, fp->handle, ret);
break;
}
binder_debug(BINDER_DEBUG_TRANSACTION,
- " ref %d desc %d (node %d)\n",
- ref->debug_id, ref->desc, ref->node->debug_id);
- binder_dec_ref(ref, hdr->type == BINDER_TYPE_HANDLE);
+ " ref %d desc %d\n",
+ rdata.debug_id, rdata.desc);
} break;

case BINDER_TYPE_FD: {
@@ -1209,9 +1438,10 @@ static int binder_translate_binder(struct flat_binder_object *fp,
struct binder_thread *thread)
{
struct binder_node *node;
- struct binder_ref *ref;
struct binder_proc *proc = thread->proc;
struct binder_proc *target_proc = t->to_proc;
+ struct binder_ref_data rdata;
+ int ret;

node = binder_get_node(proc, fp->binder);
if (!node) {
@@ -1232,25 +1462,25 @@ static int binder_translate_binder(struct flat_binder_object *fp,
if (security_binder_transfer_binder(proc->tsk, target_proc->tsk))
return -EPERM;

- ref = binder_get_ref_for_node(target_proc, node);
- if (!ref)
- return -ENOMEM;
+ ret = binder_inc_ref_for_node(target_proc, node,
+ fp->hdr.type == BINDER_TYPE_BINDER,
+ &thread->todo, &rdata);
+ if (ret)
+ return ret;

if (fp->hdr.type == BINDER_TYPE_BINDER)
fp->hdr.type = BINDER_TYPE_HANDLE;
else
fp->hdr.type = BINDER_TYPE_WEAK_HANDLE;
fp->binder = 0;
- fp->handle = ref->desc;
+ fp->handle = rdata.desc;
fp->cookie = 0;
- binder_inc_ref(ref, fp->hdr.type == BINDER_TYPE_HANDLE, &thread->todo);

- trace_binder_transaction_node_to_ref(t, node, ref);
+ trace_binder_transaction_node_to_ref(t, node, &rdata);
binder_debug(BINDER_DEBUG_TRANSACTION,
" node %d u%016llx -> ref %d desc %d\n",
node->debug_id, (u64)node->ptr,
- ref->debug_id, ref->desc);
-
+ rdata.debug_id, rdata.desc);
return 0;
}

@@ -1258,13 +1488,14 @@ static int binder_translate_handle(struct flat_binder_object *fp,
struct binder_transaction *t,
struct binder_thread *thread)
{
- struct binder_ref *ref;
struct binder_proc *proc = thread->proc;
struct binder_proc *target_proc = t->to_proc;
+ struct binder_node *node;
+ struct binder_ref_data src_rdata;

- ref = binder_get_ref(proc, fp->handle,
- fp->hdr.type == BINDER_TYPE_HANDLE);
- if (!ref) {
+ node = binder_get_node_from_ref(proc, fp->handle,
+ fp->hdr.type == BINDER_TYPE_HANDLE, &src_rdata);
+ if (!node) {
binder_user_error("%d:%d got transaction with invalid handle, %d\n",
proc->pid, thread->pid, fp->handle);
return -EINVAL;
@@ -1272,37 +1503,41 @@ static int binder_translate_handle(struct flat_binder_object *fp,
if (security_binder_transfer_binder(proc->tsk, target_proc->tsk))
return -EPERM;

- if (ref->node->proc == target_proc) {
+ if (node->proc == target_proc) {
if (fp->hdr.type == BINDER_TYPE_HANDLE)
fp->hdr.type = BINDER_TYPE_BINDER;
else
fp->hdr.type = BINDER_TYPE_WEAK_BINDER;
- fp->binder = ref->node->ptr;
- fp->cookie = ref->node->cookie;
- binder_inc_node(ref->node, fp->hdr.type == BINDER_TYPE_BINDER,
+ fp->binder = node->ptr;
+ fp->cookie = node->cookie;
+ binder_inc_node(node,
+ fp->hdr.type == BINDER_TYPE_BINDER,
0, NULL);
- trace_binder_transaction_ref_to_node(t, ref);
+ trace_binder_transaction_ref_to_node(t, node, &src_rdata);
binder_debug(BINDER_DEBUG_TRANSACTION,
" ref %d desc %d -> node %d u%016llx\n",
- ref->debug_id, ref->desc, ref->node->debug_id,
- (u64)ref->node->ptr);
+ src_rdata.debug_id, src_rdata.desc, node->debug_id,
+ (u64)node->ptr);
} else {
- struct binder_ref *new_ref;
+ int ret;
+ struct binder_ref_data dest_rdata;

- new_ref = binder_get_ref_for_node(target_proc, ref->node);
- if (!new_ref)
- return -ENOMEM;
+ ret = binder_inc_ref_for_node(target_proc, node,
+ fp->hdr.type == BINDER_TYPE_HANDLE,
+ NULL, &dest_rdata);
+ if (ret)
+ return ret;

fp->binder = 0;
- fp->handle = new_ref->desc;
+ fp->handle = dest_rdata.desc;
fp->cookie = 0;
- binder_inc_ref(new_ref, fp->hdr.type == BINDER_TYPE_HANDLE,
- NULL);
- trace_binder_transaction_ref_to_ref(t, ref, new_ref);
+ trace_binder_transaction_ref_to_ref(t, node, &src_rdata,
+ &dest_rdata);
binder_debug(BINDER_DEBUG_TRANSACTION,
" ref %d desc %d -> ref %d desc %d (node %d)\n",
- ref->debug_id, ref->desc, new_ref->debug_id,
- new_ref->desc, ref->node->debug_id);
+ src_rdata.debug_id, src_rdata.desc,
+ dest_rdata.debug_id, dest_rdata.desc,
+ node->debug_id);
}
return 0;
}
@@ -2043,6 +2278,8 @@ static int binder_thread_write(struct binder_proc *proc,
void __user *end = buffer + size;

while (ptr < end && thread->return_error.cmd == BR_OK) {
+ int ret;
+
if (get_user(cmd, (uint32_t __user *)ptr))
return -EFAULT;
ptr += sizeof(uint32_t);
@@ -2058,62 +2295,61 @@ static int binder_thread_write(struct binder_proc *proc,
case BC_RELEASE:
case BC_DECREFS: {
uint32_t target;
- struct binder_ref *ref = NULL;
const char *debug_string;
+ bool strong = cmd == BC_ACQUIRE || cmd == BC_RELEASE;
+ bool increment = cmd == BC_INCREFS || cmd == BC_ACQUIRE;
+ struct binder_ref_data rdata;

if (get_user(target, (uint32_t __user *)ptr))
return -EFAULT;

ptr += sizeof(uint32_t);
- if (target == 0 &&
- (cmd == BC_INCREFS || cmd == BC_ACQUIRE)) {
+ ret = -1;
+ if (increment && !target) {
struct binder_node *ctx_mgr_node;
-
mutex_lock(&context->context_mgr_node_lock);
ctx_mgr_node = context->binder_context_mgr_node;
- if (ctx_mgr_node) {
- ref = binder_get_ref_for_node(proc,
- ctx_mgr_node);
- if (ref && ref->desc != target) {
- binder_user_error("%d:%d tried to acquire reference to desc 0, got %d instead\n",
- proc->pid, thread->pid,
- ref->desc);
- }
- }
+ if (ctx_mgr_node)
+ ret = binder_inc_ref_for_node(
+ proc, ctx_mgr_node,
+ strong, NULL, &rdata);
mutex_unlock(&context->context_mgr_node_lock);
}
- if (ref == NULL)
- ref = binder_get_ref(proc, target,
- cmd == BC_ACQUIRE ||
- cmd == BC_RELEASE);
- if (ref == NULL) {
- binder_user_error("%d:%d refcount change on invalid ref %d\n",
- proc->pid, thread->pid, target);
- break;
+ if (ret)
+ ret = binder_update_ref_for_handle(
+ proc, target, increment, strong,
+ &rdata);
+ if (!ret && rdata.desc != target) {
+ binder_user_error("%d:%d tried to acquire reference to desc %d, got %d instead\n",
+ proc->pid, thread->pid,
+ target, rdata.desc);
}
switch (cmd) {
case BC_INCREFS:
debug_string = "IncRefs";
- binder_inc_ref(ref, 0, NULL);
break;
case BC_ACQUIRE:
debug_string = "Acquire";
- binder_inc_ref(ref, 1, NULL);
break;
case BC_RELEASE:
debug_string = "Release";
- binder_dec_ref(ref, 1);
break;
case BC_DECREFS:
default:
debug_string = "DecRefs";
- binder_dec_ref(ref, 0);
+ break;
+ }
+ if (ret) {
+ binder_user_error("%d:%d %s %d refcount change on invalid ref %d ret %d\n",
+ proc->pid, thread->pid, debug_string,
+ strong, target, ret);
break;
}
binder_debug(BINDER_DEBUG_USER_REFS,
- "%d:%d %s ref %d desc %d s %d w %d for node %d\n",
- proc->pid, thread->pid, debug_string, ref->debug_id,
- ref->desc, ref->strong, ref->weak, ref->node->debug_id);
+ "%d:%d %s ref %d desc %d s %d w %d\n",
+ proc->pid, thread->pid, debug_string,
+ rdata.debug_id, rdata.desc, rdata.strong,
+ rdata.weak);
break;
}
case BC_INCREFS_DONE:
@@ -2311,8 +2547,9 @@ static int binder_thread_write(struct binder_proc *proc,
cmd == BC_REQUEST_DEATH_NOTIFICATION ?
"BC_REQUEST_DEATH_NOTIFICATION" :
"BC_CLEAR_DEATH_NOTIFICATION",
- (u64)cookie, ref->debug_id, ref->desc,
- ref->strong, ref->weak, ref->node->debug_id);
+ (u64)cookie, ref->data.debug_id,
+ ref->data.desc, ref->data.strong,
+ ref->data.weak, ref->node->debug_id);

if (cmd == BC_REQUEST_DEATH_NOTIFICATION) {
if (ref->death) {
@@ -3473,7 +3710,8 @@ static void binder_deferred_release(struct binder_proc *proc)

ref = rb_entry(n, struct binder_ref, rb_node_desc);
outgoing_refs++;
- binder_delete_ref(ref);
+ binder_cleanup_ref(ref);
+ binder_free_ref(ref);
}

binder_release_work(&proc->todo);
@@ -3675,9 +3913,11 @@ static void print_binder_node(struct seq_file *m, struct binder_node *node)

static void print_binder_ref(struct seq_file *m, struct binder_ref *ref)
{
- seq_printf(m, " ref %d: desc %d %snode %d s %d w %d d %p\n",
- ref->debug_id, ref->desc, ref->node->proc ? "" : "dead ",
- ref->node->debug_id, ref->strong, ref->weak, ref->death);
+ seq_printf(m, " ref %d: desc %d %snode %d s %d w %d d %pK\n",
+ ref->data.debug_id, ref->data.desc,
+ ref->node->proc ? "" : "dead ",
+ ref->node->debug_id, ref->data.strong,
+ ref->data.weak, ref->death);
}

static void print_binder_proc(struct seq_file *m,
@@ -3844,8 +4084,8 @@ static void print_binder_proc_stats(struct seq_file *m,
struct binder_ref *ref = rb_entry(n, struct binder_ref,
rb_node_desc);
count++;
- strong += ref->strong;
- weak += ref->weak;
+ strong += ref->data.strong;
+ weak += ref->data.weak;
}
seq_printf(m, " refs: %d s %d w %d\n", count, strong, weak);

diff --git a/drivers/android/binder_trace.h b/drivers/android/binder_trace.h
index 50b0d21f42cf..7967db16ba5a 100644
--- a/drivers/android/binder_trace.h
+++ b/drivers/android/binder_trace.h
@@ -24,7 +24,7 @@ struct binder_buffer;
struct binder_node;
struct binder_proc;
struct binder_alloc;
-struct binder_ref;
+struct binder_ref_data;
struct binder_thread;
struct binder_transaction;

@@ -147,8 +147,8 @@ TRACE_EVENT(binder_transaction_received,

TRACE_EVENT(binder_transaction_node_to_ref,
TP_PROTO(struct binder_transaction *t, struct binder_node *node,
- struct binder_ref *ref),
- TP_ARGS(t, node, ref),
+ struct binder_ref_data *rdata),
+ TP_ARGS(t, node, rdata),

TP_STRUCT__entry(
__field(int, debug_id)
@@ -161,8 +161,8 @@ TRACE_EVENT(binder_transaction_node_to_ref,
__entry->debug_id = t->debug_id;
__entry->node_debug_id = node->debug_id;
__entry->node_ptr = node->ptr;
- __entry->ref_debug_id = ref->debug_id;
- __entry->ref_desc = ref->desc;
+ __entry->ref_debug_id = rdata->debug_id;
+ __entry->ref_desc = rdata->desc;
),
TP_printk("transaction=%d node=%d src_ptr=0x%016llx ==> dest_ref=%d dest_desc=%d",
__entry->debug_id, __entry->node_debug_id,
@@ -171,8 +171,9 @@ TRACE_EVENT(binder_transaction_node_to_ref,
);

TRACE_EVENT(binder_transaction_ref_to_node,
- TP_PROTO(struct binder_transaction *t, struct binder_ref *ref),
- TP_ARGS(t, ref),
+ TP_PROTO(struct binder_transaction *t, struct binder_node *node,
+ struct binder_ref_data *rdata),
+ TP_ARGS(t, node, rdata),

TP_STRUCT__entry(
__field(int, debug_id)
@@ -183,10 +184,10 @@ TRACE_EVENT(binder_transaction_ref_to_node,
),
TP_fast_assign(
__entry->debug_id = t->debug_id;
- __entry->ref_debug_id = ref->debug_id;
- __entry->ref_desc = ref->desc;
- __entry->node_debug_id = ref->node->debug_id;
- __entry->node_ptr = ref->node->ptr;
+ __entry->ref_debug_id = rdata->debug_id;
+ __entry->ref_desc = rdata->desc;
+ __entry->node_debug_id = node->debug_id;
+ __entry->node_ptr = node->ptr;
),
TP_printk("transaction=%d node=%d src_ref=%d src_desc=%d ==> dest_ptr=0x%016llx",
__entry->debug_id, __entry->node_debug_id,
@@ -195,9 +196,10 @@ TRACE_EVENT(binder_transaction_ref_to_node,
);

TRACE_EVENT(binder_transaction_ref_to_ref,
- TP_PROTO(struct binder_transaction *t, struct binder_ref *src_ref,
- struct binder_ref *dest_ref),
- TP_ARGS(t, src_ref, dest_ref),
+ TP_PROTO(struct binder_transaction *t, struct binder_node *node,
+ struct binder_ref_data *src_ref,
+ struct binder_ref_data *dest_ref),
+ TP_ARGS(t, node, src_ref, dest_ref),

TP_STRUCT__entry(
__field(int, debug_id)
@@ -209,7 +211,7 @@ TRACE_EVENT(binder_transaction_ref_to_ref,
),
TP_fast_assign(
__entry->debug_id = t->debug_id;
- __entry->node_debug_id = src_ref->node->debug_id;
+ __entry->node_debug_id = node->debug_id;
__entry->src_ref_debug_id = src_ref->debug_id;
__entry->src_ref_desc = src_ref->desc;
__entry->dest_ref_debug_id = dest_ref->debug_id;
--
2.13.2.725.g09c95d1e9-goog