selftests: ublk: add test for checking zero copy related parameter

ublk zero copy usually requires to set dma and segment parameter correctly,
so hard-code null target's dma & segment parameter in non-default value,
and verify if they are setup correctly by ublk driver.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250327095123.179113-12-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/tools/testing/selftests/ublk/Makefile b/tools/testing/selftests/ublk/Makefile
index 7a8c994de24499c77f1c2844bfb576cf89ee749e..d98680d64a2f4bcf9795f6bb1e8c60ade5a8b58c 100644 (file)
--- a/tools/testing/selftests/ublk/Makefile
+++ b/tools/testing/selftests/ublk/Makefile
@@ -5,6 +5,7 @@ LDLIBS += -lpthread -lm -luring
 
 TEST_PROGS := test_generic_01.sh
 TEST_PROGS += test_generic_02.sh
+TEST_PROGS += test_generic_03.sh
 
 TEST_PROGS += test_null_01.sh
 TEST_PROGS += test_null_02.sh

diff --git a/tools/testing/selftests/ublk/null.c b/tools/testing/selftests/ublk/null.c
index 899875ff50feadbd734fbbf1f8fad1f19abd1e8f..91fec3690d4ba0cc1e4b0231dff6fdad411b5ecc 100644 (file)
--- a/tools/testing/selftests/ublk/null.c
+++ b/tools/testing/selftests/ublk/null.c
@@ -17,7 +17,8 @@ static int ublk_null_tgt_init(const struct dev_ctx *ctx, struct ublk_dev *dev)
 
        dev->tgt.dev_size = dev_size;
        dev->tgt.params = (struct ublk_params) {
-               .types = UBLK_PARAM_TYPE_BASIC,
+               .types = UBLK_PARAM_TYPE_BASIC | UBLK_PARAM_TYPE_DMA_ALIGN |
+                       UBLK_PARAM_TYPE_SEGMENT,
                .basic = {
                        .logical_bs_shift       = 9,
                        .physical_bs_shift      = 12,
@@ -26,6 +27,14 @@ static int ublk_null_tgt_init(const struct dev_ctx *ctx, struct ublk_dev *dev)
                        .max_sectors            = info->max_io_buf_bytes >> 9,
                        .dev_sectors            = dev_size >> 9,
                },
+               .dma = {
+                       .alignment              = 4095,
+               },
+               .seg = {
+                       .seg_boundary_mask      = 4095,
+                       .max_segment_size       = 32 << 10,
+                       .max_segments           = 32,
+               },
        };
 
        if (info->flags & UBLK_F_SUPPORT_ZERO_COPY)

diff --git a/tools/testing/selftests/ublk/test_generic_03.sh b/tools/testing/selftests/ublk/test_generic_03.sh
new file mode 100755 (executable)
index 0000000..b551aa7
--- /dev/null
+++ b/tools/testing/selftests/ublk/test_generic_03.sh
@@ -0,0 +1,28 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+
+. "$(cd "$(dirname "$0")" && pwd)"/test_common.sh
+
+TID="generic_03"
+ERR_CODE=0
+
+_prep_test "null" "check dma & segment limits for zero copy"
+
+dev_id=$(_add_ublk_dev -t null -z)
+_check_add_dev $TID $?
+
+sysfs_path=/sys/block/ublkb"${dev_id}"
+dma_align=$(cat "$sysfs_path"/queue/dma_alignment)
+max_segments=$(cat "$sysfs_path"/queue/max_segments)
+max_segment_size=$(cat "$sysfs_path"/queue/max_segment_size)
+if [ "$dma_align" != "4095" ]; then
+       ERR_CODE=255
+fi
+if [ "$max_segments" != "32" ]; then
+       ERR_CODE=255
+fi
+if [ "$max_segment_size" != "32768" ]; then
+       ERR_CODE=255
+fi
+_cleanup_test "null"
+_show_result $TID $ERR_CODE