Re: [PATCH v2] binder: use standard functions to allocate fds
From: Todd Kjos
Date: Tue Aug 28 2018 - 16:43:51 EST
Sorry, forgot to bump the version. Ignore this one.
On Tue, Aug 28, 2018 at 1:43 PM Todd Kjos <tkjos@xxxxxxxxxxx> wrote:
>
> Binder uses internal fs interfaces to allocate and install fds:
>
> __alloc_fd
> __fd_install
> __close_fd
> get_files_struct
> put_files_struct
>
> These were used to support the passing of fds between processes
> as part of a transaction. The actual allocation and installation
> of the fds in the target process was handled by the sending
> process so the standard functions, alloc_fd() and fd_install()
> which assume task==current couldn't be used.
>
> This patch refactors this mechanism so that the fds are
> allocated and installed by the target process allowing the
> standard functions to be used.
>
> The sender now creates a list of fd fixups that contains the
> struct *file and the address to fixup with the new fd once
> it is allocated. This list is processed by the target process
> when the transaction is dequeued.
>
> A new error case is introduced by this change. If an async
> transaction with file descriptors cannot allocate new
> fds in the target (probably due to out of file descriptors),
> the transaction is discarded with a log message. In the old
> implementation this would have been detected in the sender
> context and failed prior to sending.
>
> Signed-off-by: Todd Kjos <tkjos@xxxxxxxxxx>
> ---
> v2: use "%zu" printk format for size_t
>
> drivers/android/Kconfig | 2 +-
> drivers/android/binder.c | 387 ++++++++++++++++++++-------------
> drivers/android/binder_trace.h | 36 ++-
> 3 files changed, 260 insertions(+), 165 deletions(-)
>
> diff --git a/drivers/android/Kconfig b/drivers/android/Kconfig
> index 432e9ad770703..51e8250d113fa 100644
> --- a/drivers/android/Kconfig
> +++ b/drivers/android/Kconfig
> @@ -10,7 +10,7 @@ if ANDROID
>
> config ANDROID_BINDER_IPC
> bool "Android Binder IPC Driver"
> - depends on MMU
> + depends on MMU && !CPU_CACHE_VIVT
> default n
> ---help---
> Binder is used in Android for both communication between processes,
> diff --git a/drivers/android/binder.c b/drivers/android/binder.c
> index d58763b6b0090..50856319bc7da 100644
> --- a/drivers/android/binder.c
> +++ b/drivers/android/binder.c
> @@ -71,6 +71,7 @@
> #include <linux/security.h>
> #include <linux/spinlock.h>
> #include <linux/ratelimit.h>
> +#include <linux/syscalls.h>
>
> #include <uapi/linux/android/binder.h>
>
> @@ -457,9 +458,8 @@ struct binder_ref {
> };
>
> enum binder_deferred_state {
> - BINDER_DEFERRED_PUT_FILES = 0x01,
> - BINDER_DEFERRED_FLUSH = 0x02,
> - BINDER_DEFERRED_RELEASE = 0x04,
> + BINDER_DEFERRED_FLUSH = 0x01,
> + BINDER_DEFERRED_RELEASE = 0x02,
> };
>
> /**
> @@ -480,9 +480,6 @@ enum binder_deferred_state {
> * (invariant after initialized)
> * @tsk task_struct for group_leader of process
> * (invariant after initialized)
> - * @files files_struct for process
> - * (protected by @files_lock)
> - * @files_lock mutex to protect @files
> * @deferred_work_node: element for binder_deferred_list
> * (protected by binder_deferred_lock)
> * @deferred_work: bitmap of deferred work to perform
> @@ -527,8 +524,6 @@ struct binder_proc {
> struct list_head waiting_threads;
> int pid;
> struct task_struct *tsk;
> - struct files_struct *files;
> - struct mutex files_lock;
> struct hlist_node deferred_work_node;
> int deferred_work;
> bool is_dead;
> @@ -611,6 +606,23 @@ struct binder_thread {
> bool is_dead;
> };
>
> +/**
> + * struct binder_txn_fd_fixup - transaction fd fixup list element
> + * @fixup_entry: list entry
> + * @file: struct file to be associated with new fd
> + * @offset: offset in buffer data to this fixup
> + *
> + * List element for fd fixups in a transaction. Since file
> + * descriptors need to be allocated in the context of the
> + * target process, we pass each fd to be processed in this
> + * struct.
> + */
> +struct binder_txn_fd_fixup {
> + struct list_head fixup_entry;
> + struct file *file;
> + size_t offset;
> +};
> +
> struct binder_transaction {
> int debug_id;
> struct binder_work work;
> @@ -628,6 +640,7 @@ struct binder_transaction {
> long priority;
> long saved_priority;
> kuid_t sender_euid;
> + struct list_head fd_fixups;
> /**
> * @lock: protects @from, @to_proc, and @to_thread
> *
> @@ -920,66 +933,6 @@ static void binder_free_thread(struct binder_thread *thread);
> static void binder_free_proc(struct binder_proc *proc);
> static void binder_inc_node_tmpref_ilocked(struct binder_node *node);
>
> -static int task_get_unused_fd_flags(struct binder_proc *proc, int flags)
> -{
> - unsigned long rlim_cur;
> - unsigned long irqs;
> - int ret;
> -
> - mutex_lock(&proc->files_lock);
> - if (proc->files == NULL) {
> - ret = -ESRCH;
> - goto err;
> - }
> - if (!lock_task_sighand(proc->tsk, &irqs)) {
> - ret = -EMFILE;
> - goto err;
> - }
> - rlim_cur = task_rlimit(proc->tsk, RLIMIT_NOFILE);
> - unlock_task_sighand(proc->tsk, &irqs);
> -
> - ret = __alloc_fd(proc->files, 0, rlim_cur, flags);
> -err:
> - mutex_unlock(&proc->files_lock);
> - return ret;
> -}
> -
> -/*
> - * copied from fd_install
> - */
> -static void task_fd_install(
> - struct binder_proc *proc, unsigned int fd, struct file *file)
> -{
> - mutex_lock(&proc->files_lock);
> - if (proc->files)
> - __fd_install(proc->files, fd, file);
> - mutex_unlock(&proc->files_lock);
> -}
> -
> -/*
> - * copied from sys_close
> - */
> -static long task_close_fd(struct binder_proc *proc, unsigned int fd)
> -{
> - int retval;
> -
> - mutex_lock(&proc->files_lock);
> - if (proc->files == NULL) {
> - retval = -ESRCH;
> - goto err;
> - }
> - retval = __close_fd(proc->files, fd);
> - /* can't restart close syscall because file table entry was cleared */
> - if (unlikely(retval == -ERESTARTSYS ||
> - retval == -ERESTARTNOINTR ||
> - retval == -ERESTARTNOHAND ||
> - retval == -ERESTART_RESTARTBLOCK))
> - retval = -EINTR;
> -err:
> - mutex_unlock(&proc->files_lock);
> - return retval;
> -}
> -
> static bool binder_has_work_ilocked(struct binder_thread *thread,
> bool do_proc_work)
> {
> @@ -1958,10 +1911,32 @@ static struct binder_thread *binder_get_txn_from_and_acq_inner(
> return NULL;
> }
>
> +/**
> + * binder_free_txn_fixups() - free unprocessed fd fixups
> + * @t: binder transaction for t->from
> + *
> + * If the transaction is being torn down prior to being
> + * processed by the target process, free all of the
> + * fd fixups and fput the file structs. It is safe to
> + * call this function after the fixups have been
> + * processed -- in that case, the list will be empty.
> + */
> +static void binder_free_txn_fixups(struct binder_transaction *t)
> +{
> + struct binder_txn_fd_fixup *fixup, *tmp;
> +
> + list_for_each_entry_safe(fixup, tmp, &t->fd_fixups, fixup_entry) {
> + fput(fixup->file);
> + list_del(&fixup->fixup_entry);
> + kfree(fixup);
> + }
> +}
> +
> static void binder_free_transaction(struct binder_transaction *t)
> {
> if (t->buffer)
> t->buffer->transaction = NULL;
> + binder_free_txn_fixups(t);
> kfree(t);
> binder_stats_deleted(BINDER_STAT_TRANSACTION);
> }
> @@ -2262,12 +2237,17 @@ static void binder_transaction_buffer_release(struct binder_proc *proc,
> } break;
>
> case BINDER_TYPE_FD: {
> - struct binder_fd_object *fp = to_binder_fd_object(hdr);
> -
> - binder_debug(BINDER_DEBUG_TRANSACTION,
> - " fd %d\n", fp->fd);
> - if (failed_at)
> - task_close_fd(proc, fp->fd);
> + /*
> + * No need to close the file here since user-space
> + * closes it for for successfully delivered
> + * transactions. For transactions that weren't
> + * delivered, the new fd was never allocated so
> + * there is no need to close and the fput on the
> + * file is done when the transaction is torn
> + * down.
> + */
> + WARN_ON(failed_at &&
> + proc->tsk == current->group_leader);
> } break;
> case BINDER_TYPE_PTR:
> /*
> @@ -2283,6 +2263,15 @@ static void binder_transaction_buffer_release(struct binder_proc *proc,
> size_t fd_index;
> binder_size_t fd_buf_size;
>
> + if (proc->tsk != current->group_leader) {
> + /*
> + * Nothing to do if running in sender context
> + * The fd fixups have not been applied so no
> + * fds need to be closed.
> + */
> + continue;
> + }
> +
> fda = to_binder_fd_array_object(hdr);
> parent = binder_validate_ptr(buffer, fda->parent,
> off_start,
> @@ -2315,7 +2304,7 @@ static void binder_transaction_buffer_release(struct binder_proc *proc,
> }
> fd_array = (u32 *)(parent_buffer + (uintptr_t)fda->parent_offset);
> for (fd_index = 0; fd_index < fda->num_fds; fd_index++)
> - task_close_fd(proc, fd_array[fd_index]);
> + ksys_close(fd_array[fd_index]);
> } break;
> default:
> pr_err("transaction release %d bad object type %x\n",
> @@ -2447,17 +2436,18 @@ static int binder_translate_handle(struct flat_binder_object *fp,
> return ret;
> }
>
> -static int binder_translate_fd(int fd,
> +static int binder_translate_fd(u32 *fdp,
> struct binder_transaction *t,
> struct binder_thread *thread,
> struct binder_transaction *in_reply_to)
> {
> struct binder_proc *proc = thread->proc;
> struct binder_proc *target_proc = t->to_proc;
> - int target_fd;
> + struct binder_txn_fd_fixup *fixup;
> struct file *file;
> - int ret;
> + int ret = 0;
> bool target_allows_fd;
> + int fd = *fdp;
>
> if (in_reply_to)
> target_allows_fd = !!(in_reply_to->flags & TF_ACCEPT_FDS);
> @@ -2485,19 +2475,24 @@ static int binder_translate_fd(int fd,
> goto err_security;
> }
>
> - target_fd = task_get_unused_fd_flags(target_proc, O_CLOEXEC);
> - if (target_fd < 0) {
> + /*
> + * Add fixup record for this transaction. The allocation
> + * of the fd in the target needs to be done from a
> + * target thread.
> + */
> + fixup = kzalloc(sizeof(*fixup), GFP_KERNEL);
> + if (!fixup) {
> ret = -ENOMEM;
> - goto err_get_unused_fd;
> + goto err_alloc;
> }
> - task_fd_install(target_proc, target_fd, file);
> - trace_binder_transaction_fd(t, fd, target_fd);
> - binder_debug(BINDER_DEBUG_TRANSACTION, " fd %d -> %d\n",
> - fd, target_fd);
> + fixup->file = file;
> + fixup->offset = (uintptr_t)fdp - (uintptr_t)t->buffer->data;
> + trace_binder_transaction_fd_send(t, fd, fixup->offset);
> + list_add_tail(&fixup->fixup_entry, &t->fd_fixups);
>
> - return target_fd;
> + return ret;
>
> -err_get_unused_fd:
> +err_alloc:
> err_security:
> fput(file);
> err_fget:
> @@ -2511,8 +2506,7 @@ static int binder_translate_fd_array(struct binder_fd_array_object *fda,
> struct binder_thread *thread,
> struct binder_transaction *in_reply_to)
> {
> - binder_size_t fdi, fd_buf_size, num_installed_fds;
> - int target_fd;
> + binder_size_t fdi, fd_buf_size;
> uintptr_t parent_buffer;
> u32 *fd_array;
> struct binder_proc *proc = thread->proc;
> @@ -2544,23 +2538,12 @@ static int binder_translate_fd_array(struct binder_fd_array_object *fda,
> return -EINVAL;
> }
> for (fdi = 0; fdi < fda->num_fds; fdi++) {
> - target_fd = binder_translate_fd(fd_array[fdi], t, thread,
> + int ret = binder_translate_fd(&fd_array[fdi], t, thread,
> in_reply_to);
> - if (target_fd < 0)
> - goto err_translate_fd_failed;
> - fd_array[fdi] = target_fd;
> + if (ret < 0)
> + return ret;
> }
> return 0;
> -
> -err_translate_fd_failed:
> - /*
> - * Failed to allocate fd or security error, free fds
> - * installed so far.
> - */
> - num_installed_fds = fdi;
> - for (fdi = 0; fdi < num_installed_fds; fdi++)
> - task_close_fd(target_proc, fd_array[fdi]);
> - return target_fd;
> }
>
> static int binder_fixup_parent(struct binder_transaction *t,
> @@ -2911,6 +2894,7 @@ static void binder_transaction(struct binder_proc *proc,
> return_error_line = __LINE__;
> goto err_alloc_t_failed;
> }
> + INIT_LIST_HEAD(&t->fd_fixups);
> binder_stats_created(BINDER_STAT_TRANSACTION);
> spin_lock_init(&t->lock);
>
> @@ -3066,17 +3050,16 @@ static void binder_transaction(struct binder_proc *proc,
>
> case BINDER_TYPE_FD: {
> struct binder_fd_object *fp = to_binder_fd_object(hdr);
> - int target_fd = binder_translate_fd(fp->fd, t, thread,
> - in_reply_to);
> + int ret = binder_translate_fd(&fp->fd, t, thread,
> + in_reply_to);
>
> - if (target_fd < 0) {
> + if (ret < 0) {
> return_error = BR_FAILED_REPLY;
> - return_error_param = target_fd;
> + return_error_param = ret;
> return_error_line = __LINE__;
> goto err_translate_failed;
> }
> fp->pad_binder = 0;
> - fp->fd = target_fd;
> } break;
> case BINDER_TYPE_FDA: {
> struct binder_fd_array_object *fda =
> @@ -3233,6 +3216,7 @@ static void binder_transaction(struct binder_proc *proc,
> err_bad_offset:
> err_bad_parent:
> err_copy_data_failed:
> + binder_free_txn_fixups(t);
> trace_binder_transaction_failed_buffer_release(t->buffer);
> binder_transaction_buffer_release(target_proc, t->buffer, offp);
> if (target_node)
> @@ -3294,6 +3278,47 @@ static void binder_transaction(struct binder_proc *proc,
> }
> }
>
> +/**
> + * binder_free_buf() - free the specified buffer
> + * @proc: binder proc that owns buffer
> + * @buffer: buffer to be freed
> + *
> + * If buffer for an async transaction, enqueue the next async
> + * transaction from the node.
> + *
> + * Cleanup buffer and free it.
> + */
> +void
> +binder_free_buf(struct binder_proc *proc, struct binder_buffer *buffer)
> +{
> + if (buffer->transaction) {
> + buffer->transaction->buffer = NULL;
> + buffer->transaction = NULL;
> + }
> + if (buffer->async_transaction && buffer->target_node) {
> + struct binder_node *buf_node;
> + struct binder_work *w;
> +
> + buf_node = buffer->target_node;
> + binder_node_inner_lock(buf_node);
> + BUG_ON(!buf_node->has_async_transaction);
> + BUG_ON(buf_node->proc != proc);
> + w = binder_dequeue_work_head_ilocked(
> + &buf_node->async_todo);
> + if (!w) {
> + buf_node->has_async_transaction = false;
> + } else {
> + binder_enqueue_work_ilocked(
> + w, &proc->todo);
> + binder_wakeup_proc_ilocked(proc);
> + }
> + binder_node_inner_unlock(buf_node);
> + }
> + trace_binder_transaction_buffer_release(buffer);
> + binder_transaction_buffer_release(proc, buffer, NULL);
> + binder_alloc_free_buf(&proc->alloc, buffer);
> +}
> +
> static int binder_thread_write(struct binder_proc *proc,
> struct binder_thread *thread,
> binder_uintptr_t binder_buffer, size_t size,
> @@ -3480,33 +3505,7 @@ static int binder_thread_write(struct binder_proc *proc,
> proc->pid, thread->pid, (u64)data_ptr,
> buffer->debug_id,
> buffer->transaction ? "active" : "finished");
> -
> - if (buffer->transaction) {
> - buffer->transaction->buffer = NULL;
> - buffer->transaction = NULL;
> - }
> - if (buffer->async_transaction && buffer->target_node) {
> - struct binder_node *buf_node;
> - struct binder_work *w;
> -
> - buf_node = buffer->target_node;
> - binder_node_inner_lock(buf_node);
> - BUG_ON(!buf_node->has_async_transaction);
> - BUG_ON(buf_node->proc != proc);
> - w = binder_dequeue_work_head_ilocked(
> - &buf_node->async_todo);
> - if (!w) {
> - buf_node->has_async_transaction = false;
> - } else {
> - binder_enqueue_work_ilocked(
> - w, &proc->todo);
> - binder_wakeup_proc_ilocked(proc);
> - }
> - binder_node_inner_unlock(buf_node);
> - }
> - trace_binder_transaction_buffer_release(buffer);
> - binder_transaction_buffer_release(proc, buffer, NULL);
> - binder_alloc_free_buf(&proc->alloc, buffer);
> + binder_free_buf(proc, buffer);
> break;
> }
>
> @@ -3829,6 +3828,76 @@ static int binder_wait_for_work(struct binder_thread *thread,
> return ret;
> }
>
> +/**
> + * binder_apply_fd_fixups() - finish fd translation
> + * @t: binder transaction with list of fd fixups
> + *
> + * Now that we are in the context of the transaction target
> + * process, we can allocate and install fds. Process the
> + * list of fds to translate and fixup the buffer with the
> + * new fds.
> + *
> + * If we fail to allocate an fd, then free the resources by
> + * fput'ing files that have not been processed and ksys_close'ing
> + * any fds that have already been allocated.
> + */
> +static int binder_apply_fd_fixups(struct binder_transaction *t)
> +{
> + struct binder_txn_fd_fixup *fixup, *tmp;
> + int ret = 0;
> +
> + list_for_each_entry(fixup, &t->fd_fixups, fixup_entry) {
> + int fd = get_unused_fd_flags(O_CLOEXEC);
> + u32 *fdp;
> +
> + if (fd < 0) {
> + binder_debug(BINDER_DEBUG_TRANSACTION,
> + "failed fd fixup txn %d fd %d\n",
> + t->debug_id, fd);
> + ret = -ENOMEM;
> + break;
> + }
> + binder_debug(BINDER_DEBUG_TRANSACTION,
> + "fd fixup txn %d fd %d\n",
> + t->debug_id, fd);
> + trace_binder_transaction_fd_recv(t, fd, fixup->offset);
> + fd_install(fd, fixup->file);
> + fixup->file = NULL;
> + fdp = (u32 *)(t->buffer->data + fixup->offset);
> + /*
> + * This store can cause problems for CPUs with a
> + * VIVT cache (eg ARMv5) since the cache cannot
> + * detect virtual aliases to the same physical cacheline.
> + * To support VIVT, this address and the user-space VA
> + * would both need to be flushed. Since this kernel
> + * VA is not constructed via page_to_virt(), we can't
> + * use flush_dcache_page() on it, so we'd have to use
> + * an internal function. If devices with VIVT ever
> + * need to run Android, we'll either need to go back
> + * to patching the translated fd from the sender side
> + * (using the non-standard kernel functions), or rework
> + * how the kernel uses the buffer to use page_to_virt()
> + * addresses instead of allocating in our own vm area.
> + *
> + * For now, we disable compilation if CONFIG_CPU_CACHE_VIVT.
> + */
> + *fdp = fd;
> + }
> + list_for_each_entry_safe(fixup, tmp, &t->fd_fixups, fixup_entry) {
> + if (fixup->file) {
> + fput(fixup->file);
> + } else if (ret) {
> + u32 *fdp = (u32 *)(t->buffer->data + fixup->offset);
> +
> + ksys_close(*fdp);
> + }
> + list_del(&fixup->fixup_entry);
> + kfree(fixup);
> + }
> +
> + return ret;
> +}
> +
> static int binder_thread_read(struct binder_proc *proc,
> struct binder_thread *thread,
> binder_uintptr_t binder_buffer, size_t size,
> @@ -4110,6 +4179,34 @@ static int binder_thread_read(struct binder_proc *proc,
> tr.sender_pid = 0;
> }
>
> + ret = binder_apply_fd_fixups(t);
> + if (ret) {
> + struct binder_buffer *buffer = t->buffer;
> + bool oneway = !!(t->flags & TF_ONE_WAY);
> + int tid = t->debug_id;
> +
> + if (t_from)
> + binder_thread_dec_tmpref(t_from);
> + buffer->transaction = NULL;
> + binder_cleanup_transaction(t, "fd fixups failed",
> + BR_FAILED_REPLY);
> + binder_free_buf(proc, buffer);
> + binder_debug(BINDER_DEBUG_FAILED_TRANSACTION,
> + "%d:%d %stransaction %d fd fixups failed %d/%d, line %d\n",
> + proc->pid, thread->pid,
> + oneway ? "async " :
> + (cmd == BR_REPLY ? "reply " : ""),
> + tid, BR_FAILED_REPLY, ret, __LINE__);
> + if (cmd == BR_REPLY) {
> + cmd = BR_FAILED_REPLY;
> + if (put_user(cmd, (uint32_t __user *)ptr))
> + return -EFAULT;
> + ptr += sizeof(uint32_t);
> + binder_stat_br(proc, thread, cmd);
> + break;
> + }
> + continue;
> + }
> tr.data_size = t->buffer->data_size;
> tr.offsets_size = t->buffer->offsets_size;
> tr.data.ptr.buffer = (binder_uintptr_t)
> @@ -4693,7 +4790,6 @@ static void binder_vma_close(struct vm_area_struct *vma)
> (vma->vm_end - vma->vm_start) / SZ_1K, vma->vm_flags,
> (unsigned long)pgprot_val(vma->vm_page_prot));
> binder_alloc_vma_close(&proc->alloc);
> - binder_defer_work(proc, BINDER_DEFERRED_PUT_FILES);
> }
>
> static vm_fault_t binder_vm_fault(struct vm_fault *vmf)
> @@ -4739,9 +4835,6 @@ static int binder_mmap(struct file *filp, struct vm_area_struct *vma)
> ret = binder_alloc_mmap_handler(&proc->alloc, vma);
> if (ret)
> return ret;
> - mutex_lock(&proc->files_lock);
> - proc->files = get_files_struct(current);
> - mutex_unlock(&proc->files_lock);
> return 0;
>
> err_bad_arg:
> @@ -4765,7 +4858,6 @@ static int binder_open(struct inode *nodp, struct file *filp)
> spin_lock_init(&proc->outer_lock);
> get_task_struct(current->group_leader);
> proc->tsk = current->group_leader;
> - mutex_init(&proc->files_lock);
> INIT_LIST_HEAD(&proc->todo);
> proc->default_priority = task_nice(current);
> binder_dev = container_of(filp->private_data, struct binder_device,
> @@ -4915,8 +5007,6 @@ static void binder_deferred_release(struct binder_proc *proc)
> struct rb_node *n;
> int threads, nodes, incoming_refs, outgoing_refs, active_transactions;
>
> - BUG_ON(proc->files);
> -
> mutex_lock(&binder_procs_lock);
> hlist_del(&proc->proc_node);
> mutex_unlock(&binder_procs_lock);
> @@ -4998,7 +5088,6 @@ static void binder_deferred_release(struct binder_proc *proc)
> static void binder_deferred_func(struct work_struct *work)
> {
> struct binder_proc *proc;
> - struct files_struct *files;
>
> int defer;
>
> @@ -5016,23 +5105,11 @@ static void binder_deferred_func(struct work_struct *work)
> }
> mutex_unlock(&binder_deferred_lock);
>
> - files = NULL;
> - if (defer & BINDER_DEFERRED_PUT_FILES) {
> - mutex_lock(&proc->files_lock);
> - files = proc->files;
> - if (files)
> - proc->files = NULL;
> - mutex_unlock(&proc->files_lock);
> - }
> -
> if (defer & BINDER_DEFERRED_FLUSH)
> binder_deferred_flush(proc);
>
> if (defer & BINDER_DEFERRED_RELEASE)
> binder_deferred_release(proc); /* frees proc */
> -
> - if (files)
> - put_files_struct(files);
> } while (proc);
> }
> static DECLARE_WORK(binder_deferred_work, binder_deferred_func);
> diff --git a/drivers/android/binder_trace.h b/drivers/android/binder_trace.h
> index 588eb3ec35070..14de7ac57a34d 100644
> --- a/drivers/android/binder_trace.h
> +++ b/drivers/android/binder_trace.h
> @@ -223,22 +223,40 @@ TRACE_EVENT(binder_transaction_ref_to_ref,
> __entry->dest_ref_debug_id, __entry->dest_ref_desc)
> );
>
> -TRACE_EVENT(binder_transaction_fd,
> - TP_PROTO(struct binder_transaction *t, int src_fd, int dest_fd),
> - TP_ARGS(t, src_fd, dest_fd),
> +TRACE_EVENT(binder_transaction_fd_send,
> + TP_PROTO(struct binder_transaction *t, int fd, size_t offset),
> + TP_ARGS(t, fd, offset),
>
> TP_STRUCT__entry(
> __field(int, debug_id)
> - __field(int, src_fd)
> - __field(int, dest_fd)
> + __field(int, fd)
> + __field(size_t, offset)
> + ),
> + TP_fast_assign(
> + __entry->debug_id = t->debug_id;
> + __entry->fd = fd;
> + __entry->offset = offset;
> + ),
> + TP_printk("transaction=%d src_fd=%d offset=%zu",
> + __entry->debug_id, __entry->fd, __entry->offset)
> +);
> +
> +TRACE_EVENT(binder_transaction_fd_recv,
> + TP_PROTO(struct binder_transaction *t, int fd, size_t offset),
> + TP_ARGS(t, fd, offset),
> +
> + TP_STRUCT__entry(
> + __field(int, debug_id)
> + __field(int, fd)
> + __field(size_t, offset)
> ),
> TP_fast_assign(
> __entry->debug_id = t->debug_id;
> - __entry->src_fd = src_fd;
> - __entry->dest_fd = dest_fd;
> + __entry->fd = fd;
> + __entry->offset = offset;
> ),
> - TP_printk("transaction=%d src_fd=%d ==> dest_fd=%d",
> - __entry->debug_id, __entry->src_fd, __entry->dest_fd)
> + TP_printk("transaction=%d dest_fd=%d offset=%zu",
> + __entry->debug_id, __entry->fd, __entry->offset)
> );
>
> DECLARE_EVENT_CLASS(binder_buffer_class,
> --
> 2.19.0.rc0.228.g281dcd1b4d0-goog
>