"Daniel Almeida" <daniel.almeida@xxxxxxxxxxxxx> writes:
> Hi Andreas,
>
>> On 11 Jul 2025, at 08:43, Andreas Hindborg <a.hindborg@xxxxxxxxxx> wrote:
>>
>> Use the new `NullTerminatedFormatter` to write the name of a `GenDisk` to
>> the name buffer. This new formatter automatically adds a trailing null
>> marker after the written characters, so we don't need to append that at the
>> call site any longer.
>>
>> Signed-off-by: Andreas Hindborg <a.hindborg@xxxxxxxxxx>
>> ---
>> rust/kernel/block/mq/gen_disk.rs | 11 ++++++-----
>> rust/kernel/block/mq/raw_writer.rs | 1 +
>> rust/kernel/str.rs | 1 -
>> 3 files changed, 7 insertions(+), 6 deletions(-)
>>
>> diff --git a/rust/kernel/block/mq/gen_disk.rs b/rust/kernel/block/mq/gen_disk.rs
>> index 679ee1bb2195..39be2a31337f 100644
>> --- a/rust/kernel/block/mq/gen_disk.rs
>> +++ b/rust/kernel/block/mq/gen_disk.rs
>> @@ -7,9 +7,10 @@
>>
>> use crate::{
>> bindings,
>> - block::mq::{raw_writer::RawWriter, Operations, TagSet},
>> + block::mq::{Operations, TagSet},
>> error::{self, from_err_ptr, Result},
>> static_lock_class,
>> + str::NullTerminatedFormatter,
>> sync::Arc,
>> };
>> use core::fmt::{self, Write};
>> @@ -143,14 +144,14 @@ 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 = NullTerminatedFormatter::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')?;
>> + )
>> + .ok_or(error::code::EINVAL)?;
>> + writer.write_fmt(name)?;
>>
>> // 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/block/mq/raw_writer.rs b/rust/kernel/block/mq/raw_writer.rs
>> index 7e2159e4f6a6..0aef55703e71 100644
>> --- a/rust/kernel/block/mq/raw_writer.rs
>> +++ b/rust/kernel/block/mq/raw_writer.rs
>> @@ -24,6 +24,7 @@ fn new(buffer: &'a mut [u8]) -> Result<RawWriter<'a>> {
>> Ok(Self { buffer, pos: 0 })
>> }
>>
>> + #[expect(dead_code)]
>
> Not sure I understand, is this superseded by..
>
>> pub(crate) fn from_array<const N: usize>(
>> a: &'a mut [crate::ffi::c_char; N],
>> ) -> Result<RawWriter<'a>> {
>> diff --git a/rust/kernel/str.rs b/rust/kernel/str.rs
>> index c58925438c6e..7396c49174cd 100644
>> --- a/rust/kernel/str.rs
>> +++ b/rust/kernel/str.rs
>> @@ -858,7 +858,6 @@ pub(crate) fn new(buffer: &'a mut [u8]) -> Option<NullTerminatedFormatter<'a>> {
>> Some(Self { buffer })
>> }
>>
>> - #[expect(dead_code)]
>
> … this?
>
>> pub(crate) fn from_array<const N: usize>(
>> buffer: &'a mut [crate::ffi::c_char; N],
>> ) -> Option<NullTerminatedFormatter<'a>> {
>>
Yes. Alice suggested combining patch 8/16 that removes
`block::mq::raw_writer` with this one.
Best regards,
Andreas Hindborg
