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Wed, 16 Apr 2025 10:15:49 -0700 (PDT) Received: from 1.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.ip6.arpa ([2620:10d:c091:600::1:a61d]) by smtp.gmail.com with ESMTPSA id af79cd13be357-7c7a8943834sm1084605185a.22.2025.04.16.10.15.48 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 16 Apr 2025 10:15:49 -0700 (PDT) From: Tamir Duberstein Subject: [PATCH v4 0/4] rust: alloc: split `Vec::set_len` into `Vec::{inc,dec}_len` Date: Wed, 16 Apr 2025 13:15:39 -0400 Message-Id: <20250416-vec-set-len-v4-0-112b222604cd@gmail.com> Precedence: bulk X-Mailing-List: rust-for-linux@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-B4-Tracking: v=1; b=H4sIALzl/2cC/23QywrCMBAF0F8pWRtJJn2krvwPcVGTaRvoQ5Mal NJ/N62Crbi8A+fCnZE4tAYdOUQjseiNM30XQryLiKqLrkJqdMgEGCRM8JR6VNThQBvsaJ5fMFU qliKLSRBXi6V5LG2nc8i1cUNvn0u55/P1f4/nlNGUlbksQGYgymPVFqbZq74lc4+HtZVbC8FCL nSSlBI0l79WfG3Msq0VwapEF0wzATzFtZ3egyze7uErw2fVNL0AtatkATMBAAA= X-Change-ID: 20250316-vec-set-len-99be6cc48374 To: Danilo Krummrich , Andrew Ballance , Alice Ryhl , Miguel Ojeda , Alex Gaynor , Boqun Feng , Gary Guo , =?utf-8?q?Bj=C3=B6rn_Roy_Baron?= , Benno Lossin , Andreas Hindborg , Trevor Gross Cc: rust-for-linux@vger.kernel.org, linux-kernel@vger.kernel.org, Tamir Duberstein X-Mailer: b4 0.15-dev This series is the product of a discussion[0] on the safety requirements of `set_len`. Link: https://lore.kernel.org/all/20250315154436.65065-1-dakr@kernel.org/ [0] Signed-off-by: Tamir Duberstein --- Changes in v4: - Rebase on rust/alloc-next to resolve conflict with "rust: alloc: use `spare_capacity_mut` to reduce unsafe". - Link: https://lore.kernel.org/all/20250318-vec-push-use-spare-v3-1-68741671d1af@gmail.com/ - Link to v3: https://lore.kernel.org/r/20250407-vec-set-len-v3-0-c5da0d03216e@gmail.com Changes in v3: - Fix compilation (s/ptr/tail/) in "refactor `Vec::truncate` using `dec_len`". - Fix grammar and s/alloc/realloc/ in a safety comment touched by "rust: alloc: add Vec::len() <= Vec::capacity invariant". - Use `if let`. (Alice Ryhl). - Avoid mutable reference after `drop_in_place`. (Alice Ryhl). - Rebase on rust/alloc-next. - Remove dependency on the `Vec::truncate` series which has been merged. - Link to v2: https://lore.kernel.org/r/20250318-vec-set-len-v2-0-293d55f82d18@gmail.com Changes in v2: - Avoid overflow in `set_len`. (Benno Lossin) - Explained `CString::try_from_fmt` usage of `set_len`. (Benno Lossin, Miguel Ojeda, Alice Ryhl) - Added missing SoB. (Alice Ryhl) - Prepend a patch documenting `Vec::len() <= Vec::capacity()` invariant. - Add a patch rewriting `Vec::truncate` in terms of `Vec::dec_len`. - Link to v1: https://lore.kernel.org/r/20250316-vec-set-len-v1-0-60f98a28723f@gmail.com --- Tamir Duberstein (4): rust: alloc: add Vec::len() <= Vec::capacity invariant rust: alloc: add `Vec::dec_len` rust: alloc: refactor `Vec::truncate` using `dec_len` rust: alloc: replace `Vec::set_len` with `inc_len` rust/kernel/alloc/kvec.rs | 81 +++++++++++++++++++++++++++-------------------- rust/kernel/str.rs | 2 +- rust/kernel/uaccess.rs | 2 +- 3 files changed, 49 insertions(+), 36 deletions(-) --- base-commit: c3152988c047a7b6abb10d4dc5e24fafbabe8b7e change-id: 20250316-vec-set-len-99be6cc48374 Best regards, -- Tamir Duberstein