Rename the `RawWriter` to `BufferWriter`, wihich is a more suitable name.
Also move the module from `block` to `str`.
The ability to format a string to a byte buffer is something that is not
specific to `block`, so there is no reason this code should live in
`block`.
Signed-off-by: Andreas Hindborg <a.hindborg@xxxxxxxxxx>
---
`BufferWriter` is used in `rnull` for interacting with `configfs`.
---
rust/kernel/block/mq.rs | 1 -
rust/kernel/block/mq/gen_disk.rs | 9 +++++----
rust/kernel/str.rs | 3 +++
.../{block/mq/raw_writer.rs => str/buffer_writer.rs} | 17 +++++++++++------
4 files changed, 19 insertions(+), 11 deletions(-)
diff --git a/rust/kernel/block/mq.rs b/rust/kernel/block/mq.rs
index fb0f393c1cea..faa3ccb5a49a 100644
--- a/rust/kernel/block/mq.rs
+++ b/rust/kernel/block/mq.rs
@@ -89,7 +89,6 @@
pub mod gen_disk;
mod operations;
-mod raw_writer;
mod request;
mod tag_set;
diff --git a/rust/kernel/block/mq/gen_disk.rs b/rust/kernel/block/mq/gen_disk.rs
index cd54cd64ea88..a04b709514ac 100644
--- a/rust/kernel/block/mq/gen_disk.rs
+++ b/rust/kernel/block/mq/gen_disk.rs
@@ -5,10 +5,11 @@
//! C header: [`include/linux/blkdev.h`](srctree/include/linux/blkdev.h)
//! C header: [`include/linux/blk_mq.h`](srctree/include/linux/blk_mq.h)
-use crate::block::mq::{raw_writer::RawWriter, Operations, TagSet};
+use crate::block::mq::{Operations, TagSet};
use crate::{bindings, error::from_err_ptr, error::Result, sync::Arc};
use crate::{error, static_lock_class};
use core::fmt::{self, Write};
+use kernel::str::BufferWriter;
/// A builder for [`GenDisk`].
///
@@ -139,14 +140,14 @@ pub fn build<T: Operations>(
// SAFETY: `gendisk` is a valid pointer as we initialized it above
unsafe { (*gendisk).fops = &TABLE };
- let mut raw_writer = RawWriter::from_array(
+ let mut writer = BufferWriter::from_array(
// SAFETY: `gendisk` points to a valid and initialized instance. We
// have exclusive access, since the disk is not added to the VFS
// yet.
unsafe { &mut (*gendisk).disk_name },
)?;
- raw_writer.write_fmt(name)?;
- raw_writer.write_char('\0')?;
+ writer.write_fmt(name)?;
+ writer.write_char('\0')?;
// SAFETY: `gendisk` points to a valid and initialized instance of
// `struct gendisk`. `set_capacity` takes a lock to synchronize this
diff --git a/rust/kernel/str.rs b/rust/kernel/str.rs
index a927db8e079c..050793fb7d3a 100644
--- a/rust/kernel/str.rs
+++ b/rust/kernel/str.rs
@@ -936,3 +936,6 @@ fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
macro_rules! fmt {
($($f:tt)*) => ( ::core::format_args!($($f)*) )
}
+
+mod buffer_writer;
+pub use buffer_writer::BufferWriter;
diff --git a/rust/kernel/block/mq/raw_writer.rs b/rust/kernel/str/buffer_writer.rs
similarity index 77%
rename from rust/kernel/block/mq/raw_writer.rs
rename to rust/kernel/str/buffer_writer.rs
index 7e2159e4f6a6..364842a6cff8 100644
--- a/rust/kernel/block/mq/raw_writer.rs
+++ b/rust/kernel/str/buffer_writer.rs
@@ -10,14 +10,14 @@
/// # Invariants
///
/// `buffer` is always null terminated.
-pub(crate) struct RawWriter<'a> {
+pub struct BufferWriter<'a> {
buffer: &'a mut [u8],
pos: usize,
}
-impl<'a> RawWriter<'a> {
- /// Create a new `RawWriter` instance.
- fn new(buffer: &'a mut [u8]) -> Result<RawWriter<'a>> {
+impl<'a> BufferWriter<'a> {
+ /// Create a new [`Self`] instance.
+ pub fn new(buffer: &'a mut [u8]) -> Result<BufferWriter<'a>> {
*(buffer.last_mut().ok_or(EINVAL)?) = 0;
// INVARIANT: We null terminated the buffer above.
@@ -26,16 +26,21 @@ fn new(buffer: &'a mut [u8]) -> Result<RawWriter<'a>> {
pub(crate) fn from_array<const N: usize>(
a: &'a mut [crate::ffi::c_char; N],
- ) -> Result<RawWriter<'a>> {
+ ) -> Result<BufferWriter<'a>> {
Self::new(
// SAFETY: the buffer of `a` is valid for read and write as `u8` for
// at least `N` bytes.
unsafe { core::slice::from_raw_parts_mut(a.as_mut_ptr().cast::<u8>(), N) },
)
}
+
+ /// Return the position of the write pointer in the underlying buffer.
+ pub fn pos(&self) -> usize {
+ self.pos
+ }
}
-impl Write for RawWriter<'_> {
+impl Write for BufferWriter<'_> {
fn write_str(&mut self, s: &str) -> fmt::Result {
let bytes = s.as_bytes();
let len = bytes.len();
--
2.47.2
