target: simplify reservations code

We do not support host-level reservations for the pscsi backend, and all
virtual backends are newere than SCSI-2, so just make the combined
SPC-3 + SCSI-2 support the only supported variant and kill the switches
for the different implementations, given that this code handles the no-op
version just fine.

(hch: Update DRF_SPC2_RESERVATIONS lock usage)

Signed-off-by: Christoph Hellwig <hch@lst.de>

6 files changed, 127 insertions, 269 deletions

diff --git a/drivers/target/target_core_configfs.c b/drivers/target/target_core_configfs.c
index 7272016ed05f..3d5570da41eb 100644
--- a/drivers/target/target_core_configfs.c
+++ b/drivers/target/target_core_configfs.c
@@ -970,13 +970,8 @@ static struct target_core_dev_pr_attribute target_core_dev_pr_##_name =	\
         __CONFIGFS_EATTR_RO(_name,                                      \
         target_core_dev_pr_show_attr_##_name);
 
-/*
- * res_holder
- */
-static ssize_t target_core_dev_pr_show_spc3_res(
-        struct se_device *dev,
-        char *page,
-        ssize_t *len)
+static ssize_t target_core_dev_pr_show_spc3_res(struct se_device *dev,
+                char *page)
 {
         struct se_node_acl *se_nacl;
         struct t10_pr_registration *pr_reg;
@@ -985,68 +980,52 @@ static ssize_t target_core_dev_pr_show_spc3_res(
 
         memset(i_buf, 0, PR_REG_ISID_ID_LEN);
 
-        spin_lock(&dev->dev_reservation_lock);
         pr_reg = dev->dev_pr_res_holder;
-        if (!pr_reg) {
-                *len += sprintf(page + *len, "No SPC-3 Reservation holder\n");
-                spin_unlock(&dev->dev_reservation_lock);
-                return *len;
-        }
+        if (!pr_reg)
+                return sprintf(page, "No SPC-3 Reservation holder\n");
+
         se_nacl = pr_reg->pr_reg_nacl;
         prf_isid = core_pr_dump_initiator_port(pr_reg, &i_buf[0],
                                 PR_REG_ISID_ID_LEN);
 
-        *len += sprintf(page + *len, "SPC-3 Reservation: %s Initiator: %s%s\n",
+        return sprintf(page, "SPC-3 Reservation: %s Initiator: %s%s\n",
                 se_nacl->se_tpg->se_tpg_tfo->get_fabric_name(),
                 se_nacl->initiatorname, (prf_isid) ? &i_buf[0] : "");
-        spin_unlock(&dev->dev_reservation_lock);
-
-        return *len;
 }
 
-static ssize_t target_core_dev_pr_show_spc2_res(
-        struct se_device *dev,
-        char *page,
-        ssize_t *len)
+static ssize_t target_core_dev_pr_show_spc2_res(struct se_device *dev,
+                char *page)
 {
         struct se_node_acl *se_nacl;
+        ssize_t len;
 
-        spin_lock(&dev->dev_reservation_lock);
         se_nacl = dev->dev_reserved_node_acl;
-        if (!se_nacl) {
-                *len += sprintf(page + *len, "No SPC-2 Reservation holder\n");
-                spin_unlock(&dev->dev_reservation_lock);
-                return *len;
+        if (se_nacl) {
+                len = sprintf(page,
+                              "SPC-2 Reservation: %s Initiator: %s\n",
+                              se_nacl->se_tpg->se_tpg_tfo->get_fabric_name(),
+                              se_nacl->initiatorname);
+        } else {
+                len = sprintf(page, "No SPC-2 Reservation holder\n");
         }
-        *len += sprintf(page + *len, "SPC-2 Reservation: %s Initiator: %s\n",
-                se_nacl->se_tpg->se_tpg_tfo->get_fabric_name(),
-                se_nacl->initiatorname);
-        spin_unlock(&dev->dev_reservation_lock);
-
-        return *len;
+        return len;
 }
 
 static ssize_t target_core_dev_pr_show_attr_res_holder(struct se_device *dev,
                 char *page)
 {
-        ssize_t len = 0;
+        int ret;
 
-        switch (dev->t10_pr.res_type) {
-        case SPC3_PERSISTENT_RESERVATIONS:
-                target_core_dev_pr_show_spc3_res(dev, page, &len);
-                break;
-        case SPC2_RESERVATIONS:
-                target_core_dev_pr_show_spc2_res(dev, page, &len);
-                break;
-        case SPC_PASSTHROUGH:
-                len += sprintf(page+len, "Passthrough\n");
-                break;
-        default:
-                len += sprintf(page+len, "Unknown\n");
-                break;
-        }
+        if (dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV)
+                return sprintf(page, "Passthrough\n");
 
-        return len;
+        spin_lock(&dev->dev_reservation_lock);
+        if (dev->dev_reservation_flags & DRF_SPC2_RESERVATIONS)
+                ret = target_core_dev_pr_show_spc2_res(dev, page);
+        else
+                ret = target_core_dev_pr_show_spc3_res(dev, page);
+        spin_unlock(&dev->dev_reservation_lock);
+        return ret;
 }
 
 SE_DEV_PR_ATTR_RO(res_holder);
@@ -1054,31 +1033,20 @@ SE_DEV_PR_ATTR_RO(res_holder);
 static ssize_t target_core_dev_pr_show_attr_res_pr_all_tgt_pts(
                 struct se_device *dev, char *page)
 {
-        struct t10_pr_registration *pr_reg;
         ssize_t len = 0;
 
-        if (dev->t10_pr.res_type != SPC3_PERSISTENT_RESERVATIONS)
-                return len;
-
         spin_lock(&dev->dev_reservation_lock);
-        pr_reg = dev->dev_pr_res_holder;
-        if (!pr_reg) {
+        if (!dev->dev_pr_res_holder) {
                 len = sprintf(page, "No SPC-3 Reservation holder\n");
-                spin_unlock(&dev->dev_reservation_lock);
-                return len;
-        }
-        /*
-         * See All Target Ports (ALL_TG_PT) bit in spcr17, section 6.14.3
-         * Basic PERSISTENT RESERVER OUT parameter list, page 290
-         */
-        if (pr_reg->pr_reg_all_tg_pt)
+        } else if (dev->dev_pr_res_holder->pr_reg_all_tg_pt) {
                 len = sprintf(page, "SPC-3 Reservation: All Target"
                         " Ports registration\n");
-        else
+        } else {
                 len = sprintf(page, "SPC-3 Reservation: Single"
                         " Target Port registration\n");
-        spin_unlock(&dev->dev_reservation_lock);
+        }
 
+        spin_unlock(&dev->dev_reservation_lock);
         return len;
 }
 
@@ -1087,9 +1055,6 @@ SE_DEV_PR_ATTR_RO(res_pr_all_tgt_pts);
 static ssize_t target_core_dev_pr_show_attr_res_pr_generation(
                 struct se_device *dev, char *page)
 {
-        if (dev->t10_pr.res_type != SPC3_PERSISTENT_RESERVATIONS)
-                return 0;
-
         return sprintf(page, "0x%08x\n", dev->t10_pr.pr_generation);
 }
 
@@ -1108,16 +1073,13 @@ static ssize_t target_core_dev_pr_show_attr_res_pr_holder_tg_port(
         struct target_core_fabric_ops *tfo;
         ssize_t len = 0;
 
-        if (dev->t10_pr.res_type != SPC3_PERSISTENT_RESERVATIONS)
-                return len;
-
         spin_lock(&dev->dev_reservation_lock);
         pr_reg = dev->dev_pr_res_holder;
         if (!pr_reg) {
                 len = sprintf(page, "No SPC-3 Reservation holder\n");
-                spin_unlock(&dev->dev_reservation_lock);
-                return len;
+                goto out_unlock;
         }
+
         se_nacl = pr_reg->pr_reg_nacl;
         se_tpg = se_nacl->se_tpg;
         lun = pr_reg->pr_reg_tg_pt_lun;
@@ -1131,8 +1093,9 @@ static ssize_t target_core_dev_pr_show_attr_res_pr_holder_tg_port(
                 " %s Logical Unit: %u\n", lun->lun_sep->sep_rtpi,
                 tfo->get_fabric_name(), tfo->tpg_get_tag(se_tpg),
                 tfo->get_fabric_name(), lun->unpacked_lun);
-        spin_unlock(&dev->dev_reservation_lock);
 
+out_unlock:
+        spin_unlock(&dev->dev_reservation_lock);
         return len;
 }
 
@@ -1148,9 +1111,6 @@ static ssize_t target_core_dev_pr_show_attr_res_pr_registered_i_pts(
         ssize_t len = 0;
         int reg_count = 0, prf_isid;
 
-        if (dev->t10_pr.res_type != SPC3_PERSISTENT_RESERVATIONS)
-                return len;
-
         len += sprintf(page+len, "SPC-3 PR Registrations:\n");
 
         spin_lock(&dev->t10_pr.registration_lock);
@@ -1190,20 +1150,16 @@ static ssize_t target_core_dev_pr_show_attr_res_pr_type(
         struct t10_pr_registration *pr_reg;
         ssize_t len = 0;
 
-        if (dev->t10_pr.res_type != SPC3_PERSISTENT_RESERVATIONS)
-                return len;
-
         spin_lock(&dev->dev_reservation_lock);
         pr_reg = dev->dev_pr_res_holder;
-        if (!pr_reg) {
+        if (pr_reg) {
+                len = sprintf(page, "SPC-3 Reservation Type: %s\n",
+                        core_scsi3_pr_dump_type(pr_reg->pr_res_type));
+        } else {
                 len = sprintf(page, "No SPC-3 Reservation holder\n");
-                spin_unlock(&dev->dev_reservation_lock);
-                return len;
         }
-        len = sprintf(page, "SPC-3 Reservation Type: %s\n",
-                core_scsi3_pr_dump_type(pr_reg->pr_res_type));
-        spin_unlock(&dev->dev_reservation_lock);
 
+        spin_unlock(&dev->dev_reservation_lock);
         return len;
 }
 
@@ -1212,24 +1168,12 @@ SE_DEV_PR_ATTR_RO(res_pr_type);
 static ssize_t target_core_dev_pr_show_attr_res_type(
                 struct se_device *dev, char *page)
 {
-        ssize_t len = 0;
-
-        switch (dev->t10_pr.res_type) {
-        case SPC3_PERSISTENT_RESERVATIONS:
-                len = sprintf(page, "SPC3_PERSISTENT_RESERVATIONS\n");
-                break;
-        case SPC2_RESERVATIONS:
-                len = sprintf(page, "SPC2_RESERVATIONS\n");
-                break;
-        case SPC_PASSTHROUGH:
-                len = sprintf(page, "SPC_PASSTHROUGH\n");
-                break;
-        default:
-                len = sprintf(page, "UNKNOWN\n");
-                break;
-        }
-
-        return len;
+        if (dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV)
+                return sprintf(page, "SPC_PASSTHROUGH\n");
+        else if (dev->dev_reservation_flags & DRF_SPC2_RESERVATIONS)
+                return sprintf(page, "SPC2_RESERVATIONS\n");
+        else
+                return sprintf(page, "SPC3_PERSISTENT_RESERVATIONS\n");
 }
 
 SE_DEV_PR_ATTR_RO(res_type);
@@ -1237,7 +1181,7 @@ SE_DEV_PR_ATTR_RO(res_type);
 static ssize_t target_core_dev_pr_show_attr_res_aptpl_active(
                 struct se_device *dev, char *page)
 {
-        if (dev->t10_pr.res_type != SPC3_PERSISTENT_RESERVATIONS)
+        if (dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV)
                 return 0;
 
         return sprintf(page, "APTPL Bit Status: %s\n",
@@ -1252,7 +1196,7 @@ SE_DEV_PR_ATTR_RO(res_aptpl_active);
 static ssize_t target_core_dev_pr_show_attr_res_aptpl_metadata(
                 struct se_device *dev, char *page)
 {
-        if (dev->t10_pr.res_type != SPC3_PERSISTENT_RESERVATIONS)
+        if (dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV)
                 return 0;
 
         return sprintf(page, "Ready to process PR APTPL metadata..\n");
@@ -1299,7 +1243,9 @@ static ssize_t target_core_dev_pr_store_attr_res_aptpl_metadata(
         u16 port_rpti = 0, tpgt = 0;
         u8 type = 0, scope;
 
-        if (dev->t10_pr.res_type != SPC3_PERSISTENT_RESERVATIONS)
+        if (dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV)
+                return 0;
+        if (dev->dev_reservation_flags & DRF_SPC2_RESERVATIONS)
                 return 0;
 
         if (dev->export_count) {
diff --git a/drivers/target/target_core_device.c b/drivers/target/target_core_device.c
index 6a27e7fd33fb..4ae1d3913821 100644
--- a/drivers/target/target_core_device.c
+++ b/drivers/target/target_core_device.c
@@ -1398,7 +1398,6 @@ struct se_device *target_alloc_device(struct se_hba *hba, const char *name)
         dev->dev_attrib.emulate_tas = DA_EMULATE_TAS;
         dev->dev_attrib.emulate_tpu = DA_EMULATE_TPU;
         dev->dev_attrib.emulate_tpws = DA_EMULATE_TPWS;
-        dev->dev_attrib.emulate_reservations = DA_EMULATE_RESERVATIONS;
         dev->dev_attrib.emulate_alua = DA_EMULATE_ALUA;
         dev->dev_attrib.enforce_pr_isids = DA_ENFORCE_PR_ISIDS;
         dev->dev_attrib.is_nonrot = DA_IS_NONROT;
@@ -1447,8 +1446,6 @@ int target_configure_device(struct se_device *dev)
         dev->dev_index = scsi_get_new_index(SCSI_DEVICE_INDEX);
         dev->creation_time = get_jiffies_64();
 
-        core_setup_reservations(dev);
-
         ret = core_setup_alua(dev);
         if (ret)
                 goto out;
diff --git a/drivers/target/target_core_pr.c b/drivers/target/target_core_pr.c
index 2b289891672f..f561a08ff8e5 100644
--- a/drivers/target/target_core_pr.c
+++ b/drivers/target/target_core_pr.c
@@ -68,49 +68,32 @@ int core_pr_dump_initiator_port(
 static void __core_scsi3_complete_pro_release(struct se_device *, struct se_node_acl *,
                         struct t10_pr_registration *, int);
 
-static int core_scsi2_reservation_seq_non_holder(
-        struct se_cmd *cmd,
-        unsigned char *cdb,
-        u32 pr_reg_type)
+static int target_scsi2_reservation_check(struct se_cmd *cmd)
 {
-        switch (cdb[0]) {
+        struct se_device *dev = cmd->se_dev;
+        struct se_session *sess = cmd->se_sess;
+
+        switch (cmd->t_task_cdb[0]) {
         case INQUIRY:
         case RELEASE:
         case RELEASE_10:
                 return 0;
         default:
-                return 1;
+                break;
         }
 
-        return 1;
-}
-
-static int core_scsi2_reservation_check(struct se_cmd *cmd, u32 *pr_reg_type)
-{
-        struct se_device *dev = cmd->se_dev;
-        struct se_session *sess = cmd->se_sess;
-        int ret;
-
-        if (!sess)
+        if (!dev->dev_reserved_node_acl || !sess)
                 return 0;
 
-        spin_lock(&dev->dev_reservation_lock);
-        if (!dev->dev_reserved_node_acl || !sess) {
-                spin_unlock(&dev->dev_reservation_lock);
-                return 0;
-        }
-        if (dev->dev_reserved_node_acl != sess->se_node_acl) {
-                spin_unlock(&dev->dev_reservation_lock);
-                return -EINVAL;
-        }
-        if (!(dev->dev_reservation_flags & DRF_SPC2_RESERVATIONS_WITH_ISID)) {
-                spin_unlock(&dev->dev_reservation_lock);
-                return 0;
+        if (dev->dev_reserved_node_acl != sess->se_node_acl)
+                return -EBUSY;
+
+        if (dev->dev_reservation_flags & DRF_SPC2_RESERVATIONS_WITH_ISID) {
+                if (dev->dev_res_bin_isid != sess->sess_bin_isid)
+                        return -EBUSY;
         }
-        ret = (dev->dev_res_bin_isid == sess->sess_bin_isid) ? 0 : -EINVAL;
-        spin_unlock(&dev->dev_reservation_lock);
 
-        return ret;
+        return 0;
 }
 
 static struct t10_pr_registration *core_scsi3_locate_pr_reg(struct se_device *,
@@ -123,12 +106,8 @@ static int target_check_scsi2_reservation_conflict(struct se_cmd *cmd)
         struct se_device *dev = cmd->se_dev;
         struct t10_pr_registration *pr_reg;
         struct t10_reservation *pr_tmpl = &dev->t10_pr;
-        int crh = (dev->t10_pr.res_type == SPC3_PERSISTENT_RESERVATIONS);
         int conflict = 0;
 
-        if (!crh)
-                return -EINVAL;
-
         pr_reg = core_scsi3_locate_pr_reg(cmd->se_dev, se_sess->se_node_acl,
                         se_sess);
         if (pr_reg) {
@@ -319,9 +298,9 @@ out:
  */
 static int core_scsi3_pr_seq_non_holder(
         struct se_cmd *cmd,
-        unsigned char *cdb,
         u32 pr_reg_type)
 {
+        unsigned char *cdb = cmd->t_task_cdb;
         struct se_dev_entry *se_deve;
         struct se_session *se_sess = cmd->se_sess;
         int other_cdb = 0, ignore_reg;
@@ -330,17 +309,11 @@ static int core_scsi3_pr_seq_non_holder(
         int we = 0; /* Write Exclusive */
         int legacy = 0; /* Act like a legacy device and return
                          * RESERVATION CONFLICT on some CDBs */
-        /*
-         * A legacy SPC-2 reservation is being held.
-         */
-        if (cmd->se_dev->dev_reservation_flags & DRF_SPC2_RESERVATIONS)
-                return core_scsi2_reservation_seq_non_holder(cmd,
-                                        cdb, pr_reg_type);
 
         se_deve = se_sess->se_node_acl->device_list[cmd->orig_fe_lun];
         /*
          * Determine if the registration should be ignored due to
-         * non-matching ISIDs in core_scsi3_pr_reservation_check().
+         * non-matching ISIDs in target_scsi3_pr_reservation_check().
          */
         ignore_reg = (pr_reg_type & 0x80000000);
         if (ignore_reg)
@@ -563,6 +536,36 @@ static int core_scsi3_pr_seq_non_holder(
         return 1; /* Conflict by default */
 }
 
+static int target_scsi3_pr_reservation_check(struct se_cmd *cmd)
+{
+        struct se_device *dev = cmd->se_dev;
+        struct se_session *sess = cmd->se_sess;
+        u32 pr_reg_type;
+
+        if (!dev->dev_pr_res_holder)
+                return 0;
+
+        pr_reg_type = dev->dev_pr_res_holder->pr_res_type;
+        cmd->pr_res_key = dev->dev_pr_res_holder->pr_res_key;
+        if (dev->dev_pr_res_holder->pr_reg_nacl != sess->se_node_acl)
+                goto check_nonholder;
+
+        if (dev->dev_pr_res_holder->isid_present_at_reg) {
+                if (dev->dev_pr_res_holder->pr_reg_bin_isid !=
+                    sess->sess_bin_isid) {
+                        pr_reg_type |= 0x80000000;
+                        goto check_nonholder;
+                }
+        }
+
+        return 0;
+
+check_nonholder:
+        if (core_scsi3_pr_seq_non_holder(cmd, pr_reg_type))
+                return -EBUSY;
+        return 0;
+}
+
 static u32 core_scsi3_pr_generation(struct se_device *dev)
 {
         u32 prg;
@@ -583,50 +586,6 @@ static u32 core_scsi3_pr_generation(struct se_device *dev)
         return prg;
 }
 
-static int core_scsi3_pr_reservation_check(
-        struct se_cmd *cmd,
-        u32 *pr_reg_type)
-{
-        struct se_device *dev = cmd->se_dev;
-        struct se_session *sess = cmd->se_sess;
-        int ret;
-
-        if (!sess)
-                return 0;
-        /*
-         * A legacy SPC-2 reservation is being held.
-         */
-        if (dev->dev_reservation_flags & DRF_SPC2_RESERVATIONS)
-                return core_scsi2_reservation_check(cmd, pr_reg_type);
-
-        spin_lock(&dev->dev_reservation_lock);
-        if (!dev->dev_pr_res_holder) {
-                spin_unlock(&dev->dev_reservation_lock);
-                return 0;
-        }
-        *pr_reg_type = dev->dev_pr_res_holder->pr_res_type;
-        cmd->pr_res_key = dev->dev_pr_res_holder->pr_res_key;
-        if (dev->dev_pr_res_holder->pr_reg_nacl != sess->se_node_acl) {
-                spin_unlock(&dev->dev_reservation_lock);
-                return -EINVAL;
-        }
-        if (!dev->dev_pr_res_holder->isid_present_at_reg) {
-                spin_unlock(&dev->dev_reservation_lock);
-                return 0;
-        }
-        ret = (dev->dev_pr_res_holder->pr_reg_bin_isid ==
-               sess->sess_bin_isid) ? 0 : -EINVAL;
-        /*
-         * Use bit in *pr_reg_type to notify ISID mismatch in
-         * core_scsi3_pr_seq_non_holder().
-         */
-        if (ret != 0)
-                *pr_reg_type |= 0x80000000;
-        spin_unlock(&dev->dev_reservation_lock);
-
-        return ret;
-}
-
 static struct t10_pr_registration *__core_scsi3_do_alloc_registration(
         struct se_device *dev,
         struct se_node_acl *nacl,
@@ -998,7 +957,7 @@ int core_scsi3_check_aptpl_registration(
         struct se_node_acl *nacl = lun_acl->se_lun_nacl;
         struct se_dev_entry *deve = nacl->device_list[lun_acl->mapped_lun];
 
-        if (dev->t10_pr.res_type != SPC3_PERSISTENT_RESERVATIONS)
+        if (dev->dev_reservation_flags & DRF_SPC2_RESERVATIONS)
                 return 0;
 
         return __core_scsi3_check_aptpl_registration(dev, tpg, lun,
@@ -4343,49 +4302,24 @@ int target_scsi3_emulate_pr_in(struct se_cmd *cmd)
         return ret;
 }
 
-static int core_pt_reservation_check(struct se_cmd *cmd, u32 *pr_res_type)
+int target_check_reservation(struct se_cmd *cmd)
 {
-        return 0;
-}
+        struct se_device *dev = cmd->se_dev;
+        int ret;
 
-static int core_pt_seq_non_holder(
-        struct se_cmd *cmd,
-        unsigned char *cdb,
-        u32 pr_reg_type)
-{
-        return 0;
-}
+        if (!cmd->se_sess)
+                return 0;
+        if (dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE)
+                return 0;
+        if (dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV)
+                return 0;
 
-void core_setup_reservations(struct se_device *dev)
-{
-        struct t10_reservation *rest = &dev->t10_pr;
+        spin_lock(&dev->dev_reservation_lock);
+        if (dev->dev_reservation_flags & DRF_SPC2_RESERVATIONS)
+                ret = target_scsi2_reservation_check(cmd);
+        else
+                ret = target_scsi3_pr_reservation_check(cmd);
+        spin_unlock(&dev->dev_reservation_lock);
 
-        /*
-         * If this device is from Target_Core_Mod/pSCSI, use the reservations
-         * of the Underlying SCSI hardware.  In Linux/SCSI terms, this can
-         * cause a problem because libata and some SATA RAID HBAs appear
-         * under Linux/SCSI, but to emulate reservations themselves.
-         */
-        if ((dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE) ||
-            (dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV &&
-             !dev->dev_attrib.emulate_reservations)) {
-                rest->res_type = SPC_PASSTHROUGH;
-                rest->pr_ops.t10_reservation_check = &core_pt_reservation_check;
-                rest->pr_ops.t10_seq_non_holder = &core_pt_seq_non_holder;
-                pr_debug("%s: Using SPC_PASSTHROUGH, no reservation"
-                        " emulation\n", dev->transport->name);
-        } else if (dev->transport->get_device_rev(dev) >= SCSI_3) {
-                rest->res_type = SPC3_PERSISTENT_RESERVATIONS;
-                rest->pr_ops.t10_reservation_check = &core_scsi3_pr_reservation_check;
-                rest->pr_ops.t10_seq_non_holder = &core_scsi3_pr_seq_non_holder;
-                pr_debug("%s: Using SPC3_PERSISTENT_RESERVATIONS"
-                        " emulation\n", dev->transport->name);
-        } else {
-                rest->res_type = SPC2_RESERVATIONS;
-                rest->pr_ops.t10_reservation_check = &core_scsi2_reservation_check;
-                rest->pr_ops.t10_seq_non_holder =
-                                &core_scsi2_reservation_seq_non_holder;
-                pr_debug("%s: Using SPC2_RESERVATIONS emulation\n",
-                        dev->transport->name);
-        }
+        return ret;
 }
diff --git a/drivers/target/target_core_pr.h b/drivers/target/target_core_pr.h
index 78451437d2c2..7616f2690ca0 100644
--- a/drivers/target/target_core_pr.h
+++ b/drivers/target/target_core_pr.h
@@ -63,6 +63,6 @@ extern unsigned char *core_scsi3_pr_dump_type(int);
 
 extern int target_scsi3_emulate_pr_in(struct se_cmd *);
 extern int target_scsi3_emulate_pr_out(struct se_cmd *);
-extern void core_setup_reservations(struct se_device *);
+extern int target_check_reservation(struct se_cmd *cmd);
 
 #endif /* TARGET_CORE_PR_H */
diff --git a/drivers/target/target_core_spc.c b/drivers/target/target_core_spc.c
index 8ca62631ec7f..862e4347f68f 100644
--- a/drivers/target/target_core_spc.c
+++ b/drivers/target/target_core_spc.c
@@ -1003,14 +1003,12 @@ int spc_parse_cdb(struct se_cmd *cmd, unsigned int *size)
                 *size = (cdb[7] << 8) + cdb[8];
                 break;
         case PERSISTENT_RESERVE_IN:
-                if (dev->t10_pr.res_type == SPC3_PERSISTENT_RESERVATIONS)
-                        cmd->execute_cmd = target_scsi3_emulate_pr_in;
                 *size = (cdb[7] << 8) + cdb[8];
+                cmd->execute_cmd = target_scsi3_emulate_pr_in;
                 break;
         case PERSISTENT_RESERVE_OUT:
-                if (dev->t10_pr.res_type == SPC3_PERSISTENT_RESERVATIONS)
-                        cmd->execute_cmd = target_scsi3_emulate_pr_out;
                 *size = (cdb[7] << 8) + cdb[8];
+                cmd->execute_cmd = target_scsi3_emulate_pr_out;
                 break;
         case RELEASE:
         case RELEASE_10:
@@ -1019,8 +1017,7 @@ int spc_parse_cdb(struct se_cmd *cmd, unsigned int *size)
                 else
                         *size = cmd->data_length;
 
-                if (dev->t10_pr.res_type != SPC_PASSTHROUGH)
-                        cmd->execute_cmd = target_scsi2_reservation_release;
+                cmd->execute_cmd = target_scsi2_reservation_release;
                 break;
         case RESERVE:
         case RESERVE_10:
@@ -1033,15 +1030,7 @@ int spc_parse_cdb(struct se_cmd *cmd, unsigned int *size)
                 else
                         *size = cmd->data_length;
 
-                /*
-                 * Setup the legacy emulated handler for SPC-2 and
-                 * >= SPC-3 compatible reservation handling (CRH=1)
-                 * Otherwise, we assume the underlying SCSI logic is
-                 * is running in SPC_PASSTHROUGH, and wants reservations
-                 * emulation disabled.
-                 */
-                if (dev->t10_pr.res_type != SPC_PASSTHROUGH)
-                        cmd->execute_cmd = target_scsi2_reservation_reserve;
+                cmd->execute_cmd = target_scsi2_reservation_reserve;
                 break;
         case REQUEST_SENSE:
                 *size = cdb[4];
diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c
index 757e3777ce79..e996bdf480cf 100644
--- a/drivers/target/target_core_transport.c
+++ b/drivers/target/target_core_transport.c
@@ -1103,7 +1103,6 @@ int target_setup_cmd_from_cdb(
         unsigned char *cdb)
 {
         struct se_device *dev = cmd->se_dev;
-        u32 pr_reg_type = 0;
         u8 alua_ascq = 0;
         unsigned long flags;
         int ret;
@@ -1180,20 +1179,13 @@ int target_setup_cmd_from_cdb(
         /*
          * Check status for SPC-3 Persistent Reservations
          */
-        if (dev->t10_pr.pr_ops.t10_reservation_check(cmd, &pr_reg_type)) {
-                if (dev->t10_pr.pr_ops.t10_seq_non_holder(
-                                        cmd, cdb, pr_reg_type) != 0) {
-                        cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
-                        cmd->se_cmd_flags |= SCF_SCSI_RESERVATION_CONFLICT;
-                        cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
-                        cmd->scsi_sense_reason = TCM_RESERVATION_CONFLICT;
-                        return -EBUSY;
-                }
-                /*
-                 * This means the CDB is allowed for the SCSI Initiator port
-                 * when said port is *NOT* holding the legacy SPC-2 or
-                 * SPC-3 Persistent Reservation.
-                 */
+        ret = target_check_reservation(cmd);
+        if (ret) {
+                cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
+                cmd->se_cmd_flags |= SCF_SCSI_RESERVATION_CONFLICT;
+                cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
+                cmd->scsi_sense_reason = TCM_RESERVATION_CONFLICT;
+                return ret;
         }
 
         ret = dev->transport->parse_cdb(cmd);