The dummy RAID controller serves 2 purposes:
(1) commands that are addressed to an inexistent LUN are redirected to it
(2) it provides a LUN 0 by default which is required by the SCSI spec
.
(1) is obviously wrong because instead of "wrong lun" "invalid cdb" is returned
to the initiator. A "shadow LUN" of type NO_LUN is now used for this purpose.
This LU uses bs_null as backingstore, so there are no idle threads spawned for
it (in contrast to the previous dummy raid controller at LUN 0).
(2) confuses some OSes / users (Windows prompts for drivers,
Solaris repeatedly tries to online the LU, but does not succeed).
It's now the user's responsibility to attach a LU to LUN 0 to adhere to the
SCSI spec (Solaris / WinXP don't insist, Linux does!).
Signed-off-by: Arne Redlich <arne.redlich@xxxxxxxxxxxxxx>
---
usr/Makefile | 2 +-
usr/list.h | 3 ++
usr/nolun.c | 95 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
usr/spc.c | 10 ++++++
usr/spc.h | 1 +
usr/target.c | 24 +++++++++-----
usr/target.h | 2 +
usr/tgtadm.c | 5 +--
8 files changed, 128 insertions(+), 14 deletions(-)
create mode 100644 usr/nolun.c
diff --git a/usr/Makefile b/usr/Makefile
index 6019a2e..17ce671 100644
--- a/usr/Makefile
+++ b/usr/Makefile
@@ -62,7 +62,7 @@ LIBS += -lpthread
PROGRAMS += tgtd tgtadm tgtimg
SCRIPTS += ../scripts/tgt-setup-lun ../scripts/tgt-admin
TGTD_OBJS += tgtd.o mgmt.o target.o scsi.o log.o driver.o util.o work.o \
- parser.o spc.o sbc.o mmc.o osd.o scc.o smc.o \
+ parser.o spc.o sbc.o mmc.o nolun.o osd.o scc.o smc.o \
ssc.o bs_ssc.o libssc.o \
bs_null.o bs_sg.o bs.o libcrc32c.o
MANPAGES = ../doc/manpages/tgtadm.8 ../doc/manpages/tgt-admin.8 \
diff --git a/usr/list.h b/usr/list.h
index 4d76057..2df7c7c 100644
--- a/usr/list.h
+++ b/usr/list.h
@@ -32,6 +32,9 @@ static inline void INIT_LIST_HEAD(struct list_head *list)
#define list_first_entry(ptr, type, member) \
list_entry((ptr)->next, type, member)
+#define list_last_entry(ptr, type, member) \
+ list_entry((ptr)->prev, type, member)
+
static inline int list_empty(const struct list_head *head)
{
return head->next == head;
diff --git a/usr/nolun.c b/usr/nolun.c
new file mode 100644
index 0000000..0f516a0
--- /dev/null
+++ b/usr/nolun.c
@@ -0,0 +1,95 @@
+/*
+ * Processing of SCSI commands addressed to inexistent LUNs.
+ *
+ * Based on scc.c:
+ *
+ * Copyright (C) 2007 FUJITA Tomonori <tomof@xxxxxxx>
+ * Copyright (C) 2007 Mike Christie <michaelc@xxxxxxxxxxx>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation, version 2 of the
+ * License.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ */
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdint.h>
+#include <unistd.h>
+#include <linux/fs.h>
+
+#include "list.h"
+#include "util.h"
+#include "tgtd.h"
+#include "target.h"
+#include "driver.h"
+#include "scsi.h"
+#include "tgtadm_error.h"
+#include "spc.h"
+
+static int nolun_lu_init(struct scsi_lu *lu)
+{
+ memset(&lu->attrs, 0x0, sizeof(lu->attrs));
+ /*
+ * TODO: use PQ 11b (per. dev. supp but not connected) and dev type 0x0
+ * (SBC-2) instead?
+ */
+ lu->attrs.device_type = 0x1f; /* unknown / no device type */
+ lu->attrs.qualifier = 0x3; /* peripheral dev. not supp. on this LU */
+
+ return 0;
+}
+
+static int nolun_lu_config(struct scsi_lu *lu __attribute__((unused)),
+ char *params __attribute__((unused)))
+{
+ return TGTADM_NO_LUN;
+}
+
+static int nolun_lu_online(struct scsi_lu *lu __attribute__((unused)))
+{
+ /* TODO: correct return value? most consumers don't check at all ... */
+ return -ENOENT;
+}
+
+static int nolun_lu_offline(struct scsi_lu *lu __attribute__((unused)))
+{
+ return 0;
+}
+
+static void nolun_lu_exit(struct scsi_lu *lu __attribute__((unused)))
+{
+ return;
+}
+
+static struct device_type_template nolun_template = {
+ .type = TYPE_NO_LUN,
+ .lu_init = nolun_lu_init,
+ .lu_config = nolun_lu_config,
+ .lu_online = nolun_lu_online,
+ .lu_offline = nolun_lu_offline,
+ .lu_exit = nolun_lu_exit,
+ .ops = {
+ [0x0 ... 0x11] = {spc_invalid_lun,},
+ {spc_inquiry,}, /* 0x12 */
+ [ 0x13 ... 0x9f] = {spc_invalid_lun},
+ {spc_report_luns,}, /* 0xA0 */
+ [0xa1 ... 0xff] = {spc_invalid_lun},
+ }
+};
+
+__attribute__((constructor)) static void nolun_init(void)
+{
+ device_type_register(&nolun_template);
+}
diff --git a/usr/spc.c b/usr/spc.c
index 1a75766..5e3f896 100644
--- a/usr/spc.c
+++ b/usr/spc.c
@@ -271,6 +271,8 @@ int spc_report_luns(int host_no, struct scsi_cmd *cmd)
nr_luns = 0;
list_for_each_entry(lu, dev_list, device_siblings) {
+ if (lu->lun == TGT_SHADOW_LUN)
+ continue;
nr_luns++;
if (!alen)
@@ -901,6 +903,14 @@ int spc_illegal_op(int host_no, struct scsi_cmd *cmd)
return SAM_STAT_CHECK_CONDITION;
}
+int spc_invalid_lun(int host_no, struct scsi_cmd *cmd)
+{
+ dump_cdb(cmd);
+ scsi_set_in_resid_by_actual(cmd, 0);
+ sense_data_build(cmd, ILLEGAL_REQUEST, ASC_LUN_NOT_SUPPORTED);
+ return SAM_STAT_CHECK_CONDITION;
+}
+
enum {
Opt_scsi_id, Opt_scsi_sn,
Opt_vendor_id, Opt_product_id,
diff --git a/usr/spc.h b/usr/spc.h
index cfc9cf3..22be22e 100644
--- a/usr/spc.h
+++ b/usr/spc.h
@@ -10,6 +10,7 @@ extern int spc_test_unit(int host_no, struct scsi_cmd *cmd);
extern int spc_request_sense(int host_no, struct scsi_cmd *cmd);
extern int spc_prevent_allow_media_removal(int host_no, struct scsi_cmd *cmd);
extern int spc_illegal_op(int host_no, struct scsi_cmd *cmd);
+extern int spc_invalid_lun(int host_no, struct scsi_cmd *cmd);
extern int spc_lu_init(struct scsi_lu *lu);
typedef int (match_fn_t)(struct scsi_lu *lu, char *params);
diff --git a/usr/target.c b/usr/target.c
index b7ea99d..13177ab 100644
--- a/usr/target.c
+++ b/usr/target.c
@@ -460,7 +460,10 @@ int tgt_device_create(int tid, int dev_type, uint64_t lun, char *params,
goto out;
}
- bst = target->bst;
+ bst = (lun == TGT_SHADOW_LUN) ?
+ get_backingstore_template("null") :
+ target->bst;
+
if (backing) {
if (bstype) {
bst = get_backingstore_template(bstype);
@@ -826,11 +829,11 @@ int target_cmd_queue(int tid, struct scsi_cmd *cmd)
cmd->dev_id = dev_id;
dprintf("%p %x %" PRIx64 "\n", cmd, cmd->scb[0], dev_id);
cmd->dev = device_lookup(target, dev_id);
- /* use LUN0 */
+ /* use TGT_SHADOW_LUN */
if (!cmd->dev)
- cmd->dev = list_first_entry(&target->device_list,
- struct scsi_lu,
- device_siblings);
+ cmd->dev = list_last_entry(&target->device_list,
+ struct scsi_lu,
+ device_siblings);
cmd->itn_lu_info = it_nexus_lu_info_lookup(itn, cmd->dev->lun);
@@ -1587,7 +1590,9 @@ int tgt_target_show_all(char *buf, int rest)
}
shprintf(total, buf, rest, _TAB1 "LUN information:\n");
- list_for_each_entry(lu, &target->device_list, device_siblings)
+ list_for_each_entry(lu, &target->device_list, device_siblings) {
+ if (lu->lun == TGT_SHADOW_LUN)
+ continue;
shprintf(total, buf, rest,
_TAB2 "LUN: %" PRIu64 "\n"
_TAB3 "Type: %s\n"
@@ -1605,6 +1610,7 @@ int tgt_target_show_all(char *buf, int rest)
lu->attrs.online ? "Yes" : "No",
lu->attrs.removable ? "Yes" : "No",
lu->path ? : "No backing store");
+ }
if (!strcmp(tgt_drivers[target->lid]->name, "iscsi")) {
int i, aid;
@@ -1721,7 +1727,7 @@ int tgt_target_create(int lld, int tid, char *args)
INIT_LIST_HEAD(&target->acl_list);
INIT_LIST_HEAD(&target->it_nexus_list);
- tgt_device_create(tid, TYPE_RAID, 0, NULL, 0);
+ tgt_device_create(tid, TYPE_NO_LUN, TGT_SHADOW_LUN, NULL, 0);
if (tgt_drivers[lld]->target_create)
tgt_drivers[lld]->target_create(target);
@@ -1748,8 +1754,8 @@ int tgt_target_destroy(int lld_no, int tid)
}
while (!list_empty(&target->device_list)) {
- /* we remove lun0 last */
- lu = list_entry(target->device_list.prev, struct scsi_lu,
+ /* we remove TGT_SHADOW_LUN last */
+ lu = list_entry(target->device_list.next, struct scsi_lu,
device_siblings);
ret = tgt_device_destroy(tid, lu->lun, 1);
if (ret)
diff --git a/usr/target.h b/usr/target.h
index 8fe30aa..26e2377 100644
--- a/usr/target.h
+++ b/usr/target.h
@@ -8,6 +8,8 @@
#define HASH_ORDER 4
#define hashfn(val) hash_long((unsigned long) (val), HASH_ORDER)
+#define TGT_SHADOW_LUN 0xffffffffffffffffULL
+
struct acl_entry {
char *address;
struct list_head aclent_list;
diff --git a/usr/tgtadm.c b/usr/tgtadm.c
index 8d9f7e2..cc4e2fd 100644
--- a/usr/tgtadm.c
+++ b/usr/tgtadm.c
@@ -673,10 +673,7 @@ int main(int argc, char **argv)
eprintf("'tid' option is necessary\n");
exit(EINVAL);
}
- if (!lun) {
- eprintf("'lun' option is necessary\n");
- exit(EINVAL);
- }
+
switch (op) {
case OP_NEW:
rc = verify_mode_params(argc, argv, "LmotlbEY");
--
1.6.0.4
--
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