linux-mm.kvack.org archive mirror
 help / color / mirror / Atom feed
From: Andreas Hindborg <a.hindborg@kernel.org>
To: "Boqun Feng" <boqun.feng@gmail.com>,
	"Jens Axboe" <axboe@kernel.dk>, "Miguel Ojeda" <ojeda@kernel.org>,
	"Gary Guo" <gary@garyguo.net>,
	"Björn Roy Baron" <bjorn3_gh@protonmail.com>,
	"Benno Lossin" <lossin@kernel.org>,
	"Alice Ryhl" <aliceryhl@google.com>,
	"Trevor Gross" <tmgross@umich.edu>,
	"Danilo Krummrich" <dakr@kernel.org>,
	"FUJITA Tomonori" <fujita.tomonori@gmail.com>,
	"Frederic Weisbecker" <frederic@kernel.org>,
	"Lyude Paul" <lyude@redhat.com>,
	"Thomas Gleixner" <tglx@kernel.org>,
	"Anna-Maria Behnsen" <anna-maria@linutronix.de>,
	"John Stultz" <jstultz@google.com>,
	"Stephen Boyd" <sboyd@kernel.org>,
	"Lorenzo Stoakes" <lorenzo.stoakes@oracle.com>,
	"Liam R. Howlett" <Liam.Howlett@oracle.com>
Cc: linux-block@vger.kernel.org, rust-for-linux@vger.kernel.org,
	 linux-kernel@vger.kernel.org, linux-mm@kvack.org,
	 Andreas Hindborg <a.hindborg@kernel.org>
Subject: [PATCH 56/79] block: rust: add abstraction for block queue feature flags
Date: Mon, 16 Feb 2026 00:35:43 +0100	[thread overview]
Message-ID: <20260216-rnull-v6-19-rc5-send-v1-56-de9a7af4b469@kernel.org> (raw)
In-Reply-To: <20260216-rnull-v6-19-rc5-send-v1-0-de9a7af4b469@kernel.org>

Add the `Feature` enum and `Features` type as Rust abstractions for the
C `blk_features_t` bitfield. These types wrap the `BLK_FEAT_*` flags
and allow drivers to describe block device capabilities such as write
cache support, FUA, rotational media, and DAX.

Signed-off-by: Andreas Hindborg <a.hindborg@kernel.org>
---
 rust/bindings/bindings_helper.h | 15 ++++++++-
 rust/kernel/block/mq.rs         |  2 ++
 rust/kernel/block/mq/feature.rs | 73 +++++++++++++++++++++++++++++++++++++++++
 3 files changed, 89 insertions(+), 1 deletion(-)

diff --git a/rust/bindings/bindings_helper.h b/rust/bindings/bindings_helper.h
index b8c2f3eadc730..209c53443e9cb 100644
--- a/rust/bindings/bindings_helper.h
+++ b/rust/bindings/bindings_helper.h
@@ -113,7 +113,6 @@ const gfp_t RUST_CONST_HELPER_GFP_NOWAIT = GFP_NOWAIT;
 const gfp_t RUST_CONST_HELPER___GFP_ZERO = __GFP_ZERO;
 const gfp_t RUST_CONST_HELPER___GFP_HIGHMEM = ___GFP_HIGHMEM;
 const gfp_t RUST_CONST_HELPER___GFP_NOWARN = ___GFP_NOWARN;
-const blk_features_t RUST_CONST_HELPER_BLK_FEAT_ROTATIONAL = BLK_FEAT_ROTATIONAL;
 const blk_status_t RUST_CONST_HELPER_BLK_STS_OK = BLK_STS_OK;
 const blk_status_t RUST_CONST_HELPER_BLK_STS_NOTSUPP = BLK_STS_NOTSUPP;
 const blk_status_t RUST_CONST_HELPER_BLK_STS_TIMEOUT = BLK_STS_TIMEOUT;
@@ -133,7 +132,21 @@ const blk_status_t RUST_CONST_HELPER_BLK_STS_ZONE_ACTIVE_RESOURCE = BLK_STS_ZONE
 const blk_status_t RUST_CONST_HELPER_BLK_STS_OFFLINE = BLK_STS_OFFLINE;
 const blk_status_t RUST_CONST_HELPER_BLK_STS_DURATION_LIMIT = BLK_STS_DURATION_LIMIT;
 const blk_status_t RUST_CONST_HELPER_BLK_STS_INVAL = BLK_STS_INVAL;
+const blk_features_t RUST_CONST_HELPER_BLK_FEAT_WRITE_CACHE = BLK_FEAT_WRITE_CACHE;
+const blk_features_t RUST_CONST_HELPER_BLK_FEAT_FUA = BLK_FEAT_FUA;
+const blk_features_t RUST_CONST_HELPER_BLK_FEAT_ROTATIONAL = BLK_FEAT_ROTATIONAL;
+const blk_features_t RUST_CONST_HELPER_BLK_FEAT_ADD_RANDOM = BLK_FEAT_ADD_RANDOM;
+const blk_features_t RUST_CONST_HELPER_BLK_FEAT_IO_STAT = BLK_FEAT_IO_STAT;
+const blk_features_t RUST_CONST_HELPER_BLK_FEAT_STABLE_WRITES = BLK_FEAT_STABLE_WRITES;
+const blk_features_t RUST_CONST_HELPER_BLK_FEAT_SYNCHRONOUS = BLK_FEAT_SYNCHRONOUS;
+const blk_features_t RUST_CONST_HELPER_BLK_FEAT_NOWAIT = BLK_FEAT_NOWAIT;
+const blk_features_t RUST_CONST_HELPER_BLK_FEAT_DAX = BLK_FEAT_DAX;
+const blk_features_t RUST_CONST_HELPER_BLK_FEAT_POLL = BLK_FEAT_POLL;
 const blk_features_t RUST_CONST_HELPER_BLK_FEAT_ZONED = BLK_FEAT_ZONED;
+const blk_features_t RUST_CONST_HELPER_BLK_FEAT_PCI_P2PDMA = BLK_FEAT_PCI_P2PDMA;
+const blk_features_t RUST_CONST_HELPER_BLK_FEAT_SKIP_TAGSET_QUIESCE = BLK_FEAT_SKIP_TAGSET_QUIESCE;
+const blk_features_t RUST_CONST_HELPER_BLK_FEAT_RAID_PARTIAL_STRIPES_EXPENSIVE = BLK_FEAT_RAID_PARTIAL_STRIPES_EXPENSIVE;
+const blk_features_t RUST_CONST_HELPER_BLK_FEAT_ATOMIC_WRITES = BLK_FEAT_ATOMIC_WRITES;
 const blk_opf_t RUST_CONST_HELPER_REQ_FAILFAST_DEV = REQ_FAILFAST_DEV;
 const blk_opf_t RUST_CONST_HELPER_REQ_FAILFAST_TRANSPORT = REQ_FAILFAST_TRANSPORT;
 const blk_opf_t RUST_CONST_HELPER_REQ_FAILFAST_DRIVER = REQ_FAILFAST_DRIVER;
diff --git a/rust/kernel/block/mq.rs b/rust/kernel/block/mq.rs
index 5a1c8e914bb9e..b36112f7b22b9 100644
--- a/rust/kernel/block/mq.rs
+++ b/rust/kernel/block/mq.rs
@@ -125,12 +125,14 @@
 //! # Ok::<(), kernel::error::Error>(())
 //! ```
 
+mod feature;
 pub mod gen_disk;
 mod operations;
 mod request;
 mod request_queue;
 pub mod tag_set;
 
+pub use feature::{Feature, Features};
 pub use operations::IoCompletionBatch;
 pub use operations::Operations;
 pub use request::Command;
diff --git a/rust/kernel/block/mq/feature.rs b/rust/kernel/block/mq/feature.rs
new file mode 100644
index 0000000000000..6c9f098e10c55
--- /dev/null
+++ b/rust/kernel/block/mq/feature.rs
@@ -0,0 +1,73 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Block device feature flags.
+//!
+//! This module provides Rust abstractions for the C `blk_features_t` type and
+//! the associated `BLK_FEAT_*` flags defined in `include/linux/blkdev.h`.
+
+use kernel::prelude::*;
+
+impl_flags! {
+    /// A set of block device feature flags.
+    ///
+    /// This type wraps the C `blk_features_t` bitfield and represents a
+    /// combination of zero or more [`Feature`] flags. It is used to describe
+    /// the capabilities of a block device in [`struct queue_limits`].
+    ///
+    /// [`struct queue_limits`]: srctree/include/linux/blkdev.h
+    #[derive(Debug, Clone, Default, Copy, PartialEq, Eq)]
+    pub struct Features(u32);
+
+    /// A block device feature flag.
+    ///
+    /// Each variant corresponds to a `BLK_FEAT_*` constant defined in
+    /// `include/linux/blkdev.h`. These flags describe individual capabilities
+    /// or properties of a block device.
+    #[derive(Debug, Clone, Copy, PartialEq, Eq)]
+    pub enum Feature {
+        /// Supports a volatile write cache.
+        WriteCache = bindings::BLK_FEAT_WRITE_CACHE,
+
+        /// Supports passing on the FUA bit.
+        ForcedUnitAccess = bindings::BLK_FEAT_FUA,
+
+        /// Rotational device (hard drive or floppy).
+        Rotational = bindings::BLK_FEAT_ROTATIONAL,
+
+        /// Contributes to the random number pool.
+        AddRandom = bindings::BLK_FEAT_ADD_RANDOM,
+
+        /// Enables disk/partitions I/O accounting.
+        IoStat = bindings::BLK_FEAT_IO_STAT,
+
+        /// Don't modify data until writeback is done.
+        StableWrites = bindings::BLK_FEAT_STABLE_WRITES,
+
+        /// Always completes in submit context.
+        Synchronous = bindings::BLK_FEAT_SYNCHRONOUS,
+
+        /// Supports REQ_NOWAIT.
+        Nowait = bindings::BLK_FEAT_NOWAIT,
+
+        /// Supports DAX.
+        Dax = bindings::BLK_FEAT_DAX,
+
+        /// Supports I/O polling.
+        Poll = bindings::BLK_FEAT_POLL,
+
+        /// Is a zoned device.
+        Zoned = bindings::BLK_FEAT_ZONED,
+
+        /// Supports PCI(e) p2p requests.
+        PciP2Pdma = bindings::BLK_FEAT_PCI_P2PDMA,
+
+        /// Skips this queue in `blk_mq_(un)quiesce_tagset`.
+        SkipTagsetQuiesce = bindings::BLK_FEAT_SKIP_TAGSET_QUIESCE,
+
+        /// Undocumented magic for bcache.
+        RaidPartialStripesExpensive = bindings::BLK_FEAT_RAID_PARTIAL_STRIPES_EXPENSIVE,
+
+        /// Atomic writes enabled.
+        AtomicWrites = bindings::BLK_FEAT_ATOMIC_WRITES,
+    }
+}

-- 
2.51.2




  parent reply	other threads:[~2026-02-16  0:49 UTC|newest]

Thread overview: 82+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-02-15 23:34 [PATCH 00/79] block: rnull: complete the rust null block driver Andreas Hindborg
2026-02-15 23:34 ` [PATCH 01/79] block: rnull: adopt new formatting guidelines Andreas Hindborg
2026-02-15 23:34 ` [PATCH 02/79] block: rnull: add module parameters Andreas Hindborg
2026-02-15 23:34 ` [PATCH 03/79] block: rnull: add macros to define configfs attributes Andreas Hindborg
2026-02-15 23:34 ` [PATCH 04/79] block: rust: fix generation of bindings to `BLK_STS_.*` Andreas Hindborg
2026-02-15 23:34 ` [PATCH 05/79] block: rust: change `queue_rq` request type to `Owned` Andreas Hindborg
2026-02-15 23:34 ` [PATCH 06/79] block: rust: add `Request` private data support Andreas Hindborg
2026-02-15 23:34 ` [PATCH 07/79] block: rust: allow `hrtimer::Timer` in `RequestData` Andreas Hindborg
2026-02-15 23:34 ` [PATCH 08/79] block: rnull: add timer completion mode Andreas Hindborg
2026-02-15 23:34 ` [PATCH 09/79] block: rust: introduce `kernel::block::bio` module Andreas Hindborg
2026-02-15 23:34 ` [PATCH 10/79] block: rust: add `command` getter to `Request` Andreas Hindborg
2026-02-15 23:34 ` [PATCH 11/79] block: rust: mq: use GFP_KERNEL from prelude Andreas Hindborg
2026-02-15 23:34 ` [PATCH 12/79] block: rust: add `TagSet` flags Andreas Hindborg
2026-02-15 23:35 ` [PATCH 13/79] block: rnull: add memory backing Andreas Hindborg
2026-02-15 23:35 ` [PATCH 14/79] block: rnull: add submit queue count config option Andreas Hindborg
2026-02-15 23:35 ` [PATCH 15/79] block: rnull: add `use_per_node_hctx` " Andreas Hindborg
2026-02-15 23:35 ` [PATCH 16/79] block: rust: allow specifying home node when constructing `TagSet` Andreas Hindborg
2026-02-15 23:35 ` [PATCH 17/79] block: rnull: allow specifying the home numa node Andreas Hindborg
2026-02-15 23:35 ` [PATCH 18/79] block: rust: add Request::sectors() method Andreas Hindborg
2026-02-15 23:35 ` [PATCH 19/79] block: rust: mq: add max_hw_discard_sectors support to GenDiskBuilder Andreas Hindborg
2026-02-15 23:35 ` [PATCH 20/79] block: rnull: add discard support Andreas Hindborg
2026-02-15 23:35 ` [PATCH 21/79] block: rust: add `NoDefaultScheduler` flag for `TagSet` Andreas Hindborg
2026-02-15 23:35 ` [PATCH 22/79] block: rnull: add no_sched module parameter and configfs attribute Andreas Hindborg
2026-02-15 23:35 ` [PATCH 23/79] block: rust: change sector type from usize to u64 Andreas Hindborg
2026-02-15 23:35 ` [PATCH 24/79] block: rust: add `BadBlocks` for bad block tracking Andreas Hindborg
2026-02-15 23:35 ` [PATCH 25/79] block: rust: mq: add Request::end() method for custom status codes Andreas Hindborg
2026-02-15 23:35 ` [PATCH 26/79] block: rnull: add badblocks support Andreas Hindborg
2026-02-15 23:35 ` [PATCH 27/79] block: rnull: add badblocks_once support Andreas Hindborg
2026-02-15 23:35 ` [PATCH 28/79] block: rnull: add partial I/O support for bad blocks Andreas Hindborg
2026-02-15 23:35 ` [PATCH 29/79] block: rust: add `TagSet` private data support Andreas Hindborg
2026-02-15 23:35 ` [PATCH 30/79] block: rust: add `hctx` " Andreas Hindborg
2026-02-15 23:35 ` [PATCH 31/79] block: rnull: add volatile cache emulation Andreas Hindborg
2026-02-15 23:35 ` [PATCH 32/79] block: rust: implement `Sync` for `GenDisk` Andreas Hindborg
2026-02-15 23:35 ` [PATCH 33/79] block: rust: add a back reference feature to `GenDisk` Andreas Hindborg
2026-02-15 23:35 ` [PATCH 34/79] block: rust: introduce an idle type state for `Request` Andreas Hindborg
2026-02-15 23:35 ` [PATCH 35/79] block: rust: add a request queue abstraction Andreas Hindborg
2026-02-15 23:35 ` [PATCH 36/79] block: rust: add a method to get the request queue for a request Andreas Hindborg
2026-02-15 23:35 ` [PATCH 37/79] block: rust: introduce `kernel::block::error` Andreas Hindborg
2026-02-15 23:35 ` [PATCH 38/79] block: rust: require `queue_rq` to return a `BlkResult` Andreas Hindborg
2026-02-15 23:35 ` [PATCH 39/79] block: rust: add `GenDisk::queue_data` Andreas Hindborg
2026-02-15 23:35 ` [PATCH 40/79] block: rnull: add bandwidth limiting Andreas Hindborg
2026-02-15 23:35 ` [PATCH 41/79] block: rnull: add blocking queue mode Andreas Hindborg
2026-02-15 23:35 ` [PATCH 42/79] block: rnull: add shared tags Andreas Hindborg
2026-02-15 23:35 ` [PATCH 43/79] block: rnull: add queue depth config option Andreas Hindborg
2026-02-15 23:35 ` [PATCH 44/79] block: rust: add an abstraction for `bindings::req_op` Andreas Hindborg
2026-02-15 23:35 ` [PATCH 45/79] block: rust: add a method to set the target sector of a request Andreas Hindborg
2026-02-15 23:35 ` [PATCH 46/79] block: rust: move gendisk vtable construction to separate function Andreas Hindborg
2026-02-15 23:35 ` [PATCH 47/79] block: rust: add zoned block device support Andreas Hindborg
2026-02-15 23:35 ` [PATCH 48/79] block: rnull: add zoned storage support Andreas Hindborg
2026-02-15 23:35 ` [PATCH 49/79] block: rust: add `map_queues` support Andreas Hindborg
2026-02-15 23:35 ` [PATCH 50/79] block: rust: add an abstraction for `struct blk_mq_queue_map` Andreas Hindborg
2026-02-15 23:35 ` [PATCH 51/79] block: rust: add polled completion support Andreas Hindborg
2026-02-15 23:35 ` [PATCH 52/79] block: rust: add accessors to `TagSet` Andreas Hindborg
2026-02-15 23:35 ` [PATCH 53/79] block: rnull: add polled completion support Andreas Hindborg
2026-02-15 23:35 ` [PATCH 54/79] block: rnull: add REQ_OP_FLUSH support Andreas Hindborg
2026-02-15 23:35 ` [PATCH 55/79] block: rust: add request flags abstraction Andreas Hindborg
2026-02-15 23:35 ` Andreas Hindborg [this message]
2026-02-15 23:35 ` [PATCH 57/79] block: rust: allow setting write cache and FUA flags for `GenDisk` Andreas Hindborg
2026-02-15 23:35 ` [PATCH 58/79] block: rust: add `Segment::copy_to_page_limit` Andreas Hindborg
2026-02-15 23:35 ` [PATCH 59/79] block: rnull: add fua support Andreas Hindborg
2026-02-15 23:35 ` [PATCH 60/79] block: fix arg type in `blk_mq_update_nr_hw_queues` Andreas Hindborg
2026-02-15 23:35 ` [PATCH 61/79] block: rust: add `GenDisk::tag_set` Andreas Hindborg
2026-02-15 23:35 ` [PATCH 62/79] block: rust: add `TagSet::update_hw_queue_count` Andreas Hindborg
2026-02-16 23:59   ` Ken Kurematsu
2026-02-17  9:54     ` Andreas Hindborg
2026-02-15 23:35 ` [PATCH 63/79] block: rnull: add an option to change the number of hardware queues Andreas Hindborg
2026-02-15 23:35 ` [PATCH 64/79] block: rust: add an abstraction for `struct rq_list` Andreas Hindborg
2026-02-15 23:35 ` [PATCH 65/79] block: rust: add `queue_rqs` vtable hook Andreas Hindborg
2026-02-15 23:35 ` [PATCH 66/79] block: rnull: support queue_rqs Andreas Hindborg
2026-02-15 23:35 ` [PATCH 67/79] block: rust: remove the `is_poll` parameter from `queue_rq` Andreas Hindborg
2026-02-15 23:35 ` [PATCH 68/79] block: rust: add a debug assert for refcounts Andreas Hindborg
2026-02-15 23:35 ` [PATCH 69/79] block: rust: add `TagSet::tag_to_rq` Andreas Hindborg
2026-02-15 23:35 ` [PATCH 70/79] block: rust: add `Request::queue_index` Andreas Hindborg
2026-02-15 23:35 ` [PATCH 71/79] block: rust: add `Request::requeue` Andreas Hindborg
2026-02-15 23:35 ` [PATCH 72/79] block: rust: add `request_timeout` hook Andreas Hindborg
2026-02-15 23:36 ` [PATCH 73/79] block: rnull: add fault injection support Andreas Hindborg
2026-02-15 23:36 ` [PATCH 74/79] block: rust: add max_sectors option to `GenDiskBuilder` Andreas Hindborg
2026-02-15 23:36 ` [PATCH 75/79] block: rnull: allow configuration of the maximum IO size Andreas Hindborg
2026-02-15 23:36 ` [PATCH 76/79] block: rust: add `virt_boundary_mask` option to `GenDiskBuilder` Andreas Hindborg
2026-02-15 23:36 ` [PATCH 77/79] block: rnull: add `virt_boundary` option Andreas Hindborg
2026-02-15 23:36 ` [PATCH 78/79] block: rnull: add `shared_tag_bitmap` config option Andreas Hindborg
2026-02-15 23:36 ` [PATCH 79/79] block: rnull: add zone offline and readonly configfs files Andreas Hindborg

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20260216-rnull-v6-19-rc5-send-v1-56-de9a7af4b469@kernel.org \
    --to=a.hindborg@kernel.org \
    --cc=Liam.Howlett@oracle.com \
    --cc=aliceryhl@google.com \
    --cc=anna-maria@linutronix.de \
    --cc=axboe@kernel.dk \
    --cc=bjorn3_gh@protonmail.com \
    --cc=boqun.feng@gmail.com \
    --cc=dakr@kernel.org \
    --cc=frederic@kernel.org \
    --cc=fujita.tomonori@gmail.com \
    --cc=gary@garyguo.net \
    --cc=jstultz@google.com \
    --cc=linux-block@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=lorenzo.stoakes@oracle.com \
    --cc=lossin@kernel.org \
    --cc=lyude@redhat.com \
    --cc=ojeda@kernel.org \
    --cc=rust-for-linux@vger.kernel.org \
    --cc=sboyd@kernel.org \
    --cc=tglx@kernel.org \
    --cc=tmgross@umich.edu \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox