[PATCH v2 2/7] scsi: scsi_debug: Add READ BLOCK LIMITS and modify LOAD for tapes

Kai Mäkisara
2025-02-13T09:27:38Z

The changes:
- add READ BLOCK LIMITS (512 - 1048576 bytes)
- make LOAD send New Media UA (not correct by the standard, but
makes possible to test also this UA)

Signed-off-by: Kai Mäkisara <Kai.Makisara@kolumbus.fi>
---
v1 -> v2:
- changed 'len +=' to 'len =' in resp_mode_sense() to fix the bug reported
by the Kernel Test Robot

drivers/scsi/scsi_debug.c | 127 ++++++++++++++++++++++++++++++++++++--
1 file changed, 121 insertions(+), 6 deletions(-)

diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c
index 4da0c259390b..21c64f79797a 100644
--- a/drivers/scsi/scsi_debug.c
+++ b/drivers/scsi/scsi_debug.c
@@ -80,6 +80,7 @@ static const char *sdebug_version_date = "20210520";
#define INVALID_FIELD_IN_CDB 0x24
#define INVALID_FIELD_IN_PARAM_LIST 0x26
#define WRITE_PROTECTED 0x27
+#define UA_READY_ASC 0x28
#define UA_RESET_ASC 0x29
#define UA_CHANGED_ASC 0x2a
#define TARGET_CHANGED_ASC 0x3f
@@ -175,7 +176,11 @@ static const char *sdebug_version_date = "20210520";

/* Default parameters for tape drives */
#define TAPE_DEF_DENSITY 0x0
+#define TAPE_BAD_DENSITY 0x65
#define TAPE_DEF_BLKSIZE 0
+#define TAPE_MIN_BLKSIZE 512
+#define TAPE_MAX_BLKSIZE 1048576
+#define TAPE_MAX_PARTITIONS 2

#define SDEBUG_LUN_0_VAL 0

@@ -220,7 +225,8 @@ static const char *sdebug_version_date = "20210520";
#define SDEBUG_UA_LUNS_CHANGED 5
#define SDEBUG_UA_MICROCODE_CHANGED 6 /* simulate firmware change */
#define SDEBUG_UA_MICROCODE_CHANGED_WO_RESET 7
-#define SDEBUG_NUM_UAS 8
+#define SDEBUG_UA_NOT_READY_TO_READY 8
+#define SDEBUG_NUM_UAS 9

/* when 1==SDEBUG_OPT_MEDIUM_ERR, a medium error is simulated at this
* sector on read commands: */
@@ -370,6 +376,8 @@ struct sdebug_dev_info {
/* For tapes */
unsigned int tape_blksize;
unsigned int tape_density;
+ unsigned char tape_partition;
+ unsigned int tape_location[TAPE_MAX_PARTITIONS];

struct dentry *debugfs_entry;
struct spinlock list_lock;
@@ -491,14 +499,16 @@ enum sdeb_opcode_index {
SDEB_I_ZONE_OUT = 30, /* 0x94+SA; includes no data xfer */
SDEB_I_ZONE_IN = 31, /* 0x95+SA; all have data-in */
SDEB_I_ATOMIC_WRITE_16 = 32,
- SDEB_I_LAST_ELEM_P1 = 33, /* keep this last (previous + 1) */
+ SDEB_I_READ_BLOCK_LIMITS = 33,
+ SDEB_I_LOCATE = 34,
+ SDEB_I_LAST_ELEM_P1 = 35, /* keep this last (previous + 1) */
};

static const unsigned char opcode_ind_arr[256] = {
/* 0x0; 0x0->0x1f: 6 byte cdbs */
SDEB_I_TEST_UNIT_READY, SDEB_I_REZERO_UNIT, 0, SDEB_I_REQUEST_SENSE,
- 0, 0, 0, 0,
+ 0, SDEB_I_READ_BLOCK_LIMITS, 0, 0,
SDEB_I_READ, 0, SDEB_I_WRITE, 0, 0, 0, 0, 0,
0, 0, SDEB_I_INQUIRY, 0, 0, SDEB_I_MODE_SELECT, SDEB_I_RESERVE,
SDEB_I_RELEASE,
@@ -506,7 +516,7 @@ static const unsigned char opcode_ind_arr[256] = {
SDEB_I_ALLOW_REMOVAL, 0,
/* 0x20; 0x20->0x3f: 10 byte cdbs */
0, 0, 0, 0, 0, SDEB_I_READ_CAPACITY, 0, 0,
- SDEB_I_READ, 0, SDEB_I_WRITE, 0, 0, 0, 0, SDEB_I_VERIFY,
+ SDEB_I_READ, 0, SDEB_I_WRITE, SDEB_I_LOCATE, 0, 0, 0, SDEB_I_VERIFY,
0, 0, 0, 0, SDEB_I_PRE_FETCH, SDEB_I_SYNC_CACHE, 0, 0,
0, 0, 0, SDEB_I_WRITE_BUFFER, 0, 0, 0, 0,
/* 0x40; 0x40->0x5f: 10 byte cdbs */
@@ -581,6 +591,8 @@ static int resp_open_zone(struct scsi_cmnd *, struct sdebug_dev_info *);
static int resp_close_zone(struct scsi_cmnd *, struct sdebug_dev_info *);
static int resp_finish_zone(struct scsi_cmnd *, struct sdebug_dev_info *);
static int resp_rwp_zone(struct scsi_cmnd *, struct sdebug_dev_info *);
+static int resp_read_blklimits(struct scsi_cmnd *, struct sdebug_dev_info *);
+static int resp_locate(struct scsi_cmnd *, struct sdebug_dev_info *);

static int sdebug_do_add_host(bool mk_new_store);
static int sdebug_add_host_helper(int per_host_idx);
@@ -808,6 +820,7 @@ static const struct opcode_info_t opcode_info_arr[SDEB_I_LAST_ELEM_P1 + 1] = {
resp_pre_fetch, pre_fetch_iarr,
{10, 0x2, 0xff, 0xff, 0xff, 0xff, 0x3f, 0xff, 0xff, 0xc7, 0, 0,
0, 0, 0, 0} }, /* PRE-FETCH (10) */
+ /* READ POSITION (10) */

/* 30 */
{ARRAY_SIZE(zone_out_iarr), 0x94, 0x3, F_SA_LOW | F_M_ACCESS,
@@ -823,6 +836,12 @@ static const struct opcode_info_t opcode_info_arr[SDEB_I_LAST_ELEM_P1 + 1] = {
resp_atomic_write, NULL, /* ATOMIC WRITE 16 */
{16, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff} },
+ {0, 0x05, 0, F_D_IN, resp_read_blklimits, NULL, /* READ BLOCK LIMITS (6) */
+ {6, 0, 0, 0, 0, 0xc7, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} },
+ {0, 0x2b, 0, F_D_UNKN, resp_locate, NULL, /* LOCATE (10) */
+ {10, 0x2, 0xff, 0xff, 0xff, 0xff, 0x3f, 0xff, 0xff, 0xc7, 0, 0,
+ 0, 0, 0, 0} },
+
/* sentinel */
{0xff, 0, 0, 0, NULL, NULL, /* terminating element */
{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} },
@@ -1501,6 +1520,12 @@ static int make_ua(struct scsi_cmnd *scp, struct sdebug_dev_info *devip)
if (sdebug_verbose)
cp = "reported luns data has changed";
break;
+ case SDEBUG_UA_NOT_READY_TO_READY:
+ mk_sense_buffer(scp, UNIT_ATTENTION, UA_READY_ASC,
+ 0);
+ if (sdebug_verbose)
+ cp = "not ready to ready transition/media change";
+ break;
default:
pr_warn("unexpected unit attention code=%d\n", k);
if (sdebug_verbose)
@@ -2204,6 +2229,14 @@ static int resp_start_stop(struct scsi_cmnd *scp, struct sdebug_dev_info *devip)
changing = (stopped_state != want_stop);
if (changing)
atomic_xchg(&devip->stopped, want_stop);
+ if (sdebug_ptype == TYPE_TAPE && !want_stop) {
+ int i;
+
+ set_bit(SDEBUG_UA_NOT_READY_TO_READY, devip->uas_bm); /* not legal! */
+ for (i = 0; i < TAPE_MAX_PARTITIONS; i++)
+ devip->tape_location[i] = 0;
+ devip->tape_partition = 0;
+ }
if (!changing || (cmd[1] & 0x1)) /* state unchanged or IMMED bit set in cdb */
return SDEG_RES_IMMED_MASK;
else
@@ -2736,6 +2769,17 @@ static int resp_sas_sha_m_spg(unsigned char *p, int pcontrol)
return sizeof(sas_sha_m_pg);
}

+static unsigned char partition_pg[] = {0x11, 12, 1, 0, 0x24, 3, 9, 0,
+ 0xff, 0xff, 0x00, 0x00};
+
+static int resp_partition_m_pg(unsigned char *p, int pcontrol, int target)
+{ /* Partition page for mode_sense (tape) */
+ memcpy(p, partition_pg, sizeof(partition_pg));
+ if (pcontrol == 1)
+ memset(p + 2, 0, sizeof(partition_pg) - 2);
+ return sizeof(partition_pg);
+}
+
/* PAGE_SIZE is more than necessary but provides room for future expansion. */
#define SDEBUG_MAX_MSENSE_SZ PAGE_SIZE

@@ -2876,6 +2920,12 @@ static int resp_mode_sense(struct scsi_cmnd *scp,
}
offset += len;
break;
+ case 0x11: /* Partition Mode Page (tape) */
+ if (!is_tape)
+ goto bad_pcode;
+ len = resp_partition_m_pg(ap, pcontrol, target);
+ offset += len;
+ break;
case 0x19: /* if spc==1 then sas phy, control+discover */
if (subpcode > 0x2 && subpcode < 0xff)
goto bad_subpcode;
@@ -2974,9 +3024,16 @@ static int resp_mode_select(struct scsi_cmnd *scp,
mselect6 ? 3 : 6, -1);
return check_condition_result;
}
+ if (arr[off] == TAPE_BAD_DENSITY) {
+ mk_sense_invalid_fld(scp, SDEB_IN_DATA, 0, -1);
+ return check_condition_result;
+ }
blksize = get_unaligned_be16(arr + off + 6);
- if ((blksize % 4) != 0) {
- mk_sense_invalid_fld(scp, SDEB_IN_DATA, off + 6, -1);
+ if (blksize != 0 &&
+ (blksize < TAPE_MIN_BLKSIZE ||
+ blksize > TAPE_MAX_BLKSIZE ||
+ (blksize % 4) != 0)) {
+ mk_sense_invalid_fld(scp, SDEB_IN_DATA, 1, -1);
return check_condition_result;
}
devip->tape_density = arr[off];
@@ -3177,6 +3234,36 @@ static int resp_log_sense(struct scsi_cmnd *scp,
min_t(u32, len, SDEBUG_MAX_INQ_ARR_SZ));
}

+enum {SDEBUG_READ_BLOCK_LIMITS_ARR_SZ = 6};
+static int resp_read_blklimits(struct scsi_cmnd *scp,
+ struct sdebug_dev_info *devip)
+{
+ unsigned char arr[SDEBUG_READ_BLOCK_LIMITS_ARR_SZ];
+
+ arr[0] = 4;
+ put_unaligned_be24(TAPE_MAX_BLKSIZE, arr + 1);
+ put_unaligned_be16(TAPE_MIN_BLKSIZE, arr + 4);
+ return fill_from_dev_buffer(scp, arr, SDEBUG_READ_BLOCK_LIMITS_ARR_SZ);
+}
+
+static int resp_locate(struct scsi_cmnd *scp,
+ struct sdebug_dev_info *devip)
+{
+ unsigned char *cmd = scp->cmnd;
+
+ if ((cmd[1] & 0x02) != 0) {
+ if (cmd[8] >= TAPE_MAX_PARTITIONS) {
+ mk_sense_invalid_fld(scp, SDEB_IN_CDB, 8, -1);
+ return check_condition_result;
+ }
+ devip->tape_partition = cmd[8];
+ }
+ devip->tape_location[devip->tape_partition] =
+ get_unaligned_be32(cmd + 3);
+
+ return 0;
+}
+
static inline bool sdebug_dev_is_zoned(struct sdebug_dev_info *devip)
{
return devip->nr_zones != 0;
@@ -4957,7 +5044,10 @@ static int resp_sync_cache(struct scsi_cmnd *scp,
* a GOOD status otherwise. Model a disk with a big cache and yield
* CONDITION MET. Actually tries to bring range in main memory into the
* cache associated with the CPU(s).
+ *
+ * The pcode 0x34 is also used for READ POSITION by tape devices.
*/
+enum {SDEBUG_READ_POSITION_ARR_SZ = 20};
static int resp_pre_fetch(struct scsi_cmnd *scp,
struct sdebug_dev_info *devip)
{
@@ -4969,6 +5059,31 @@ static int resp_pre_fetch(struct scsi_cmnd *scp,
struct sdeb_store_info *sip = devip2sip(devip, true);
u8 *fsp = sip->storep;

+ if (sdebug_ptype == TYPE_TAPE) {
+ if (cmd[0] == PRE_FETCH) { /* READ POSITION (10) */
+ int all_length;
+ unsigned char arr[20];
+ unsigned int pos;
+
+ all_length = get_unaligned_be16(cmd + 7);
+ if ((cmd[1] & 0xfe) != 0 ||
+ all_length != 0) { /* only short form */
+ mk_sense_invalid_fld(scp, SDEB_IN_CDB,
+ all_length ? 7 : 1, 0);
+ return check_condition_result;
+ }
+ memset(arr, 0, SDEBUG_READ_POSITION_ARR_SZ);
+ arr[1] = devip->tape_partition;
+ pos = devip->tape_location[devip->tape_partition];
+ put_unaligned_be32(pos, arr + 4);
+ put_unaligned_be32(pos, arr + 8);
+ return fill_from_dev_buffer(scp, arr,
+ SDEBUG_READ_POSITION_ARR_SZ);
+ }
+ mk_sense_invalid_opcode(scp);
+ return check_condition_result;
+ }
+
if (cmd[0] == PRE_FETCH) { /* 10 byte cdb */
lba = get_unaligned_be32(cmd + 2);
nblks = get_unaligned_be16(cmd + 7);
--
2.43.0