From 5a83d71b8e7d9c4565e3147817c6250e76d4e81c Mon Sep 17 00:00:00 2001
From: Daniel Xu <dxu@dxuuu.xyz>
Date: Sun, 9 Jan 2022 13:43:58 -0800
Subject: [PATCH] rust: file: Remove `is_blocking()` method

The previous commit adds a generic way to check file flags. Better not
to have two ways to do the same thing, especially when the second way is
highly specialized.

Signed-off-by: Daniel Xu <dxu@dxuuu.xyz>
---
 drivers/android/process.rs  | 5 +++--
 rust/kernel/file.rs         | 6 ------
 samples/rust/rust_random.rs | 5 +++--
 3 files changed, 6 insertions(+), 10 deletions(-)

diff --git a/drivers/android/process.rs b/drivers/android/process.rs
index 252ced2e5d9b0a..d6b25de79cb332 100644
--- a/drivers/android/process.rs
+++ b/drivers/android/process.rs
@@ -4,7 +4,7 @@ use core::{convert::TryFrom, mem::take, ops::Range};
 use kernel::{
     bindings,
     cred::Credential,
-    file::File,
+    file::{File, FileFlags},
     file_operations::{FileOperations, IoctlCommand, IoctlHandler, PollTable},
     io_buffer::{IoBufferReader, IoBufferWriter},
     linked_list::List,
@@ -794,8 +794,9 @@ impl IoctlHandler for Process {
         data: UserSlicePtr,
     ) -> Result<i32> {
         let thread = this.get_thread(Task::current().pid())?;
+        let blocking = (file.flags() & FileFlags::O_NONBLOCK) == 0;
         match cmd {
-            bindings::BINDER_WRITE_READ => thread.write_read(data, file.is_blocking())?,
+            bindings::BINDER_WRITE_READ => thread.write_read(data, blocking)?,
             bindings::BINDER_GET_NODE_DEBUG_INFO => this.get_node_debug_info(data)?,
             bindings::BINDER_GET_NODE_INFO_FOR_REF => this.get_node_info_from_ref(data)?,
             bindings::BINDER_VERSION => this.version(data)?,
diff --git a/rust/kernel/file.rs b/rust/kernel/file.rs
index 9e889e554f1b99..29784032fc71ab 100644
--- a/rust/kernel/file.rs
+++ b/rust/kernel/file.rs
@@ -127,12 +127,6 @@ impl File {
         unsafe { (*self.ptr).f_pos as u64 }
     }
 
-    /// Returns whether the file is in blocking mode.
-    pub fn is_blocking(&self) -> bool {
-        // SAFETY: `File::ptr` is guaranteed to be valid by the type invariants.
-        unsafe { (*self.ptr).f_flags & bindings::O_NONBLOCK == 0 }
-    }
-
     /// Returns the credentials of the task that originally opened the file.
     pub fn cred(&self) -> CredentialRef<'_> {
         // SAFETY: `File::ptr` is guaranteed to be valid by the type invariants.
diff --git a/samples/rust/rust_random.rs b/samples/rust/rust_random.rs
index c1319513b170a1..96e7c81b9f27b6 100644
--- a/samples/rust/rust_random.rs
+++ b/samples/rust/rust_random.rs
@@ -6,7 +6,7 @@
 //! <https://github.com/alex/just-use/blob/master/src/lib.rs>.
 
 use kernel::{
-    file::File,
+    file::{File, FileFlags},
     file_operations::FileOperations,
     io_buffer::{IoBufferReader, IoBufferWriter},
     prelude::*,
@@ -28,8 +28,9 @@ impl FileOperations for RandomFile {
         while !buf.is_empty() {
             let len = chunkbuf.len().min(buf.len());
             let chunk = &mut chunkbuf[0..len];
+            let blocking = (file.flags() & FileFlags::O_NONBLOCK) == 0;
 
-            if file.is_blocking() {
+            if blocking {
                 kernel::random::getrandom(chunk)?;
             } else {
                 kernel::random::getrandom_nonblock(chunk)?;