From 7ec5a5b8986104ab77bb800d8f659e18f52f0770 Mon Sep 17 00:00:00 2001
From: Niek Bouman <niek.git@gmail.com>
Date: Tue, 25 Feb 2025 20:24:09 +0100
Subject: [PATCH] file: document max_length-limits for dma_read/write funcs
 taking vector<iovec>

---
 include/seastar/core/file.hh | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/include/seastar/core/file.hh b/include/seastar/core/file.hh
index d7a9283076..a5b7508f5b 100644
--- a/include/seastar/core/file.hh
+++ b/include/seastar/core/file.hh
@@ -340,6 +340,9 @@ public:
     ///
     /// \return a future representing the number of bytes actually read.  A short
     ///         read may happen due to end-of-file or an I/O error.
+    ///
+    /// Note that for this overload, \ref disk_read_max_length corresponds to the sum of
+    /// the iovec sizes.
     future<size_t> dma_read(uint64_t pos, std::vector<iovec> iov, io_intent* intent = nullptr) noexcept {
         return dma_read_impl(pos, std::move(iov), internal::maybe_priority_class_ref(), intent);
     }
@@ -368,6 +371,9 @@ public:
     ///
     /// \return a future representing the number of bytes actually written.  A short
     ///         write may happen due to an I/O error.
+    ///
+    /// Note that for this overload, \ref disk_write_max_length corresponds to the sum of
+    /// the iovec sizes.
     future<size_t> dma_write(uint64_t pos, std::vector<iovec> iov, io_intent* intent = nullptr) noexcept {
         return dma_write_impl(pos, std::move(iov), internal::maybe_priority_class_ref(), intent);
     }