scsi: scsi_proto: Add structures and constants related to I/O groups and streams

Prepare for adding code that will query the I/O advice hints group
descriptors and for adding code that will retrieve the stream status.

Cc: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20240130214911.1863909-11-bvanassche@acm.orgSigned-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/Kconfig

@@ -232,6 +232,11 @@ config SCSI_SCAN_ASYNC
 	  Note that this setting also affects whether resuming from
 	  system suspend will be performed asynchronously.
 
+config SCSI_PROTO_TEST
+	tristate "scsi_proto.h unit tests" if !KUNIT_ALL_TESTS
+	depends on SCSI && KUNIT
+	default KUNIT_ALL_TESTS
+
 menu "SCSI Transports"
 	depends on SCSI
 

drivers/scsi/Makefile

@@ -24,6 +24,8 @@ obj-$(CONFIG_SCSI_COMMON)	+= scsi_common.o
 
 obj-$(CONFIG_RAID_ATTRS)	+= raid_class.o
 
+obj-$(CONFIG_SCSI_PROTO_TEST)	+= scsi_proto_test.o
+
 # --- NOTE ORDERING HERE ---
 # For kernel non-modular link, transport attributes need to
 # be initialised before drivers

drivers/scsi/scsi_proto_test.c

+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright 2023 Google LLC
+ */
+#include <kunit/test.h>
+#include <asm-generic/unaligned.h>
+#include <scsi/scsi_proto.h>
+
+static void test_scsi_proto(struct kunit *test)
+{
+	static const union {
+		struct scsi_io_group_descriptor desc;
+		u8 arr[sizeof(struct scsi_io_group_descriptor)];
+	} d = { .arr = { 0x45, 0, 0, 0, 0xb0, 0xe4, 0xe3 } };
+	KUNIT_EXPECT_EQ(test, d.desc.io_advice_hints_mode + 0, 1);
+	KUNIT_EXPECT_EQ(test, d.desc.st_enble + 0, 1);
+	KUNIT_EXPECT_EQ(test, d.desc.cs_enble + 0, 0);
+	KUNIT_EXPECT_EQ(test, d.desc.ic_enable + 0, 1);
+	KUNIT_EXPECT_EQ(test, d.desc.acdlu + 0, 1);
+	KUNIT_EXPECT_EQ(test, d.desc.rlbsr + 0, 3);
+	KUNIT_EXPECT_EQ(test, d.desc.lbm_descriptor_type + 0, 0);
+	KUNIT_EXPECT_EQ(test, d.desc.params[0] + 0, 0xe4);
+	KUNIT_EXPECT_EQ(test, d.desc.params[1] + 0, 0xe3);
+
+	static const union {
+		struct scsi_stream_status s;
+		u8 arr[sizeof(struct scsi_stream_status)];
+	} ss = { .arr = { 0x80, 0, 0x12, 0x34, 0x3f } };
+	KUNIT_EXPECT_EQ(test, ss.s.perm + 0, 1);
+	KUNIT_EXPECT_EQ(test, get_unaligned_be16(&ss.s.stream_identifier),
+			0x1234);
+	KUNIT_EXPECT_EQ(test, ss.s.rel_lifetime + 0, 0x3f);
+
+	static const union {
+		struct scsi_stream_status_header h;
+		u8 arr[sizeof(struct scsi_stream_status_header)];
+	} sh = { .arr = { 1, 2, 3, 4, 0, 0, 5, 6 } };
+	KUNIT_EXPECT_EQ(test, get_unaligned_be32(&sh.h.len), 0x1020304);
+	KUNIT_EXPECT_EQ(test, get_unaligned_be16(&sh.h.number_of_open_streams),
+			0x506);
+}
+
+static struct kunit_case scsi_proto_test_cases[] = {
+	KUNIT_CASE(test_scsi_proto),
+	{}
+};
+
+static struct kunit_suite scsi_proto_test_suite = {
+	.name = "scsi_proto",
+	.test_cases = scsi_proto_test_cases,
+};
+kunit_test_suite(scsi_proto_test_suite);
+
+MODULE_DESCRIPTION("<scsi/scsi_proto.h> unit tests");
+MODULE_AUTHOR("Bart Van Assche");
+MODULE_LICENSE("GPL");

include/scsi/scsi_proto.h

@@ -10,6 +10,7 @@
 #ifndef _SCSI_PROTO_H_
 #define _SCSI_PROTO_H_
 
+#include <linux/build_bug.h>
 #include <linux/types.h>
 
 /*
@@ -126,6 +127,7 @@
 #define	SAI_READ_CAPACITY_16  0x10
 #define SAI_GET_LBA_STATUS    0x12
 #define SAI_REPORT_REFERRALS  0x13
+#define SAI_GET_STREAM_STATUS 0x16
 /* values for maintenance in */
 #define MI_REPORT_IDENTIFYING_INFORMATION 0x05
 #define MI_REPORT_TARGET_PGS  0x0a
@@ -275,6 +277,82 @@ struct scsi_lun {
 	__u8 scsi_lun[8];
 };
 
+/* SBC-5 IO advice hints group descriptor */
+struct scsi_io_group_descriptor {
+#if defined(__BIG_ENDIAN)
+	u8 io_advice_hints_mode: 2;
+	u8 reserved1: 3;
+	u8 st_enble: 1;
+	u8 cs_enble: 1;
+	u8 ic_enable: 1;
+#elif defined(__LITTLE_ENDIAN)
+	u8 ic_enable: 1;
+	u8 cs_enble: 1;
+	u8 st_enble: 1;
+	u8 reserved1: 3;
+	u8 io_advice_hints_mode: 2;
+#else
+#error
+#endif
+	u8 reserved2[3];
+	/* Logical block markup descriptor */
+#if defined(__BIG_ENDIAN)
+	u8 acdlu: 1;
+	u8 reserved3: 1;
+	u8 rlbsr: 2;
+	u8 lbm_descriptor_type: 4;
+#elif defined(__LITTLE_ENDIAN)
+	u8 lbm_descriptor_type: 4;
+	u8 rlbsr: 2;
+	u8 reserved3: 1;
+	u8 acdlu: 1;
+#else
+#error
+#endif
+	u8 params[2];
+	u8 reserved4;
+	u8 reserved5[8];
+};
+
+static_assert(sizeof(struct scsi_io_group_descriptor) == 16);
+
+/* SCSI stream status descriptor */
+struct scsi_stream_status {
+#if defined(__BIG_ENDIAN)
+	u8 perm: 1;
+	u8 reserved1: 7;
+#elif defined(__LITTLE_ENDIAN)
+	u8 reserved1: 7;
+	u8 perm: 1;
+#else
+#error
+#endif
+	u8 reserved2;
+	__be16 stream_identifier;
+#if defined(__BIG_ENDIAN)
+	u8 reserved3: 2;
+	u8 rel_lifetime: 6;
+#elif defined(__LITTLE_ENDIAN)
+	u8 rel_lifetime: 6;
+	u8 reserved3: 2;
+#else
+#error
+#endif
+	u8 reserved4[3];
+};
+
+static_assert(sizeof(struct scsi_stream_status) == 8);
+
+/* GET STREAM STATUS parameter data */
+struct scsi_stream_status_header {
+	__be32 len;	/* length in bytes of stream_status[] array. */
+	u16 reserved;
+	__be16 number_of_open_streams;
+	DECLARE_FLEX_ARRAY(struct scsi_stream_status, stream_status);
+};
+
+static_assert(sizeof(struct scsi_stream_status_header) == 8);
+
 /* SPC asymmetric access states */
 #define SCSI_ACCESS_STATE_OPTIMAL     0x00
 #define SCSI_ACCESS_STATE_ACTIVE      0x01