Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target...
[cascardo/linux.git] / drivers / target / target_core_pr.c
index 4c261c3..d56f2aa 100644 (file)
@@ -76,7 +76,7 @@ enum preempt_type {
 };
 
 static void __core_scsi3_complete_pro_release(struct se_device *, struct se_node_acl *,
-                       struct t10_pr_registration *, int);
+                                             struct t10_pr_registration *, int, int);
 
 static sense_reason_t
 target_scsi2_reservation_check(struct se_cmd *cmd)
@@ -1177,7 +1177,7 @@ static int core_scsi3_check_implicit_release(
                 *    service action with the SERVICE ACTION RESERVATION KEY
                 *    field set to zero (see 5.7.11.3).
                 */
-               __core_scsi3_complete_pro_release(dev, nacl, pr_reg, 0);
+               __core_scsi3_complete_pro_release(dev, nacl, pr_reg, 0, 1);
                ret = 1;
                /*
                 * For 'All Registrants' reservation types, all existing
@@ -1219,7 +1219,8 @@ static void __core_scsi3_free_registration(
 
        pr_reg->pr_reg_deve->def_pr_registered = 0;
        pr_reg->pr_reg_deve->pr_res_key = 0;
-       list_del(&pr_reg->pr_reg_list);
+       if (!list_empty(&pr_reg->pr_reg_list))
+               list_del(&pr_reg->pr_reg_list);
        /*
         * Caller accessing *pr_reg using core_scsi3_locate_pr_reg(),
         * so call core_scsi3_put_pr_reg() to decrement our reference.
@@ -1271,6 +1272,7 @@ void core_scsi3_free_pr_reg_from_nacl(
 {
        struct t10_reservation *pr_tmpl = &dev->t10_pr;
        struct t10_pr_registration *pr_reg, *pr_reg_tmp, *pr_res_holder;
+       bool free_reg = false;
        /*
         * If the passed se_node_acl matches the reservation holder,
         * release the reservation.
@@ -1278,13 +1280,18 @@ void core_scsi3_free_pr_reg_from_nacl(
        spin_lock(&dev->dev_reservation_lock);
        pr_res_holder = dev->dev_pr_res_holder;
        if ((pr_res_holder != NULL) &&
-           (pr_res_holder->pr_reg_nacl == nacl))
-               __core_scsi3_complete_pro_release(dev, nacl, pr_res_holder, 0);
+           (pr_res_holder->pr_reg_nacl == nacl)) {
+               __core_scsi3_complete_pro_release(dev, nacl, pr_res_holder, 0, 1);
+               free_reg = true;
+       }
        spin_unlock(&dev->dev_reservation_lock);
        /*
         * Release any registration associated with the struct se_node_acl.
         */
        spin_lock(&pr_tmpl->registration_lock);
+       if (pr_res_holder && free_reg)
+               __core_scsi3_free_registration(dev, pr_res_holder, NULL, 0);
+
        list_for_each_entry_safe(pr_reg, pr_reg_tmp,
                        &pr_tmpl->registration_list, pr_reg_list) {
 
@@ -1307,7 +1314,7 @@ void core_scsi3_free_all_registrations(
        if (pr_res_holder != NULL) {
                struct se_node_acl *pr_res_nacl = pr_res_holder->pr_reg_nacl;
                __core_scsi3_complete_pro_release(dev, pr_res_nacl,
-                               pr_res_holder, 0);
+                                                 pr_res_holder, 0, 0);
        }
        spin_unlock(&dev->dev_reservation_lock);
 
@@ -1429,14 +1436,12 @@ core_scsi3_decode_spec_i_port(
        struct target_core_fabric_ops *tmp_tf_ops;
        unsigned char *buf;
        unsigned char *ptr, *i_str = NULL, proto_ident, tmp_proto_ident;
-       char *iport_ptr = NULL, dest_iport[64], i_buf[PR_REG_ISID_ID_LEN];
+       char *iport_ptr = NULL, i_buf[PR_REG_ISID_ID_LEN];
        sense_reason_t ret;
        u32 tpdl, tid_len = 0;
        int dest_local_nexus;
        u32 dest_rtpi = 0;
 
-       memset(dest_iport, 0, 64);
-
        local_se_deve = se_sess->se_node_acl->device_list[cmd->orig_fe_lun];
        /*
         * Allocate a struct pr_transport_id_holder and setup the
@@ -2105,13 +2110,13 @@ core_scsi3_emulate_pro_register(struct se_cmd *cmd, u64 res_key, u64 sa_res_key,
                /*
                 * sa_res_key=0 Unregister Reservation Key for registered I_T Nexus.
                 */
-               pr_holder = core_scsi3_check_implicit_release(
-                               cmd->se_dev, pr_reg);
+               type = pr_reg->pr_res_type;
+               pr_holder = core_scsi3_check_implicit_release(cmd->se_dev,
+                                                             pr_reg);
                if (pr_holder < 0) {
                        ret = TCM_RESERVATION_CONFLICT;
                        goto out;
                }
-               type = pr_reg->pr_res_type;
 
                spin_lock(&pr_tmpl->registration_lock);
                /*
@@ -2269,6 +2274,7 @@ core_scsi3_pro_reserve(struct se_cmd *cmd, int type, int scope, u64 res_key)
        spin_lock(&dev->dev_reservation_lock);
        pr_res_holder = dev->dev_pr_res_holder;
        if (pr_res_holder) {
+               int pr_res_type = pr_res_holder->pr_res_type;
                /*
                 * From spc4r17 Section 5.7.9: Reserving:
                 *
@@ -2279,7 +2285,9 @@ core_scsi3_pro_reserve(struct se_cmd *cmd, int type, int scope, u64 res_key)
                 * the logical unit, then the command shall be completed with
                 * RESERVATION CONFLICT status.
                 */
-               if (pr_res_holder != pr_reg) {
+               if ((pr_res_holder != pr_reg) &&
+                   (pr_res_type != PR_TYPE_WRITE_EXCLUSIVE_ALLREG) &&
+                   (pr_res_type != PR_TYPE_EXCLUSIVE_ACCESS_ALLREG)) {
                        struct se_node_acl *pr_res_nacl = pr_res_holder->pr_reg_nacl;
                        pr_err("SPC-3 PR: Attempted RESERVE from"
                                " [%s]: %s while reservation already held by"
@@ -2385,23 +2393,59 @@ static void __core_scsi3_complete_pro_release(
        struct se_device *dev,
        struct se_node_acl *se_nacl,
        struct t10_pr_registration *pr_reg,
-       int explicit)
+       int explicit,
+       int unreg)
 {
        struct target_core_fabric_ops *tfo = se_nacl->se_tpg->se_tpg_tfo;
        char i_buf[PR_REG_ISID_ID_LEN];
+       int pr_res_type = 0, pr_res_scope = 0;
 
        memset(i_buf, 0, PR_REG_ISID_ID_LEN);
        core_pr_dump_initiator_port(pr_reg, i_buf, PR_REG_ISID_ID_LEN);
        /*
         * Go ahead and release the current PR reservation holder.
+        * If an All Registrants reservation is currently active and
+        * a unregister operation is requested, replace the current
+        * dev_pr_res_holder with another active registration.
         */
-       dev->dev_pr_res_holder = NULL;
+       if (dev->dev_pr_res_holder) {
+               pr_res_type = dev->dev_pr_res_holder->pr_res_type;
+               pr_res_scope = dev->dev_pr_res_holder->pr_res_scope;
+               dev->dev_pr_res_holder->pr_res_type = 0;
+               dev->dev_pr_res_holder->pr_res_scope = 0;
+               dev->dev_pr_res_holder->pr_res_holder = 0;
+               dev->dev_pr_res_holder = NULL;
+       }
+       if (!unreg)
+               goto out;
 
-       pr_debug("SPC-3 PR [%s] Service Action: %s RELEASE cleared"
-               " reservation holder TYPE: %s ALL_TG_PT: %d\n",
-               tfo->get_fabric_name(), (explicit) ? "explicit" : "implicit",
-               core_scsi3_pr_dump_type(pr_reg->pr_res_type),
-               (pr_reg->pr_reg_all_tg_pt) ? 1 : 0);
+       spin_lock(&dev->t10_pr.registration_lock);
+       list_del_init(&pr_reg->pr_reg_list);
+       /*
+        * If the I_T nexus is a reservation holder, the persistent reservation
+        * is of an all registrants type, and the I_T nexus is the last remaining
+        * registered I_T nexus, then the device server shall also release the
+        * persistent reservation.
+        */
+       if (!list_empty(&dev->t10_pr.registration_list) &&
+           ((pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_ALLREG) ||
+            (pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_ALLREG))) {
+               dev->dev_pr_res_holder =
+                       list_entry(dev->t10_pr.registration_list.next,
+                                  struct t10_pr_registration, pr_reg_list);
+               dev->dev_pr_res_holder->pr_res_type = pr_res_type;
+               dev->dev_pr_res_holder->pr_res_scope = pr_res_scope;
+               dev->dev_pr_res_holder->pr_res_holder = 1;
+       }
+       spin_unlock(&dev->t10_pr.registration_lock);
+out:
+       if (!dev->dev_pr_res_holder) {
+               pr_debug("SPC-3 PR [%s] Service Action: %s RELEASE cleared"
+                       " reservation holder TYPE: %s ALL_TG_PT: %d\n",
+                       tfo->get_fabric_name(), (explicit) ? "explicit" :
+                       "implicit", core_scsi3_pr_dump_type(pr_res_type),
+                       (pr_reg->pr_reg_all_tg_pt) ? 1 : 0);
+       }
        pr_debug("SPC-3 PR [%s] RELEASE Node: %s%s\n",
                tfo->get_fabric_name(), se_nacl->initiatorname,
                i_buf);
@@ -2532,7 +2576,7 @@ core_scsi3_emulate_pro_release(struct se_cmd *cmd, int type, int scope,
         *    server shall not establish a unit attention condition.
         */
        __core_scsi3_complete_pro_release(dev, se_sess->se_node_acl,
-                       pr_reg, 1);
+                                         pr_reg, 1, 0);
 
        spin_unlock(&dev->dev_reservation_lock);
 
@@ -2620,7 +2664,7 @@ core_scsi3_emulate_pro_clear(struct se_cmd *cmd, u64 res_key)
        if (pr_res_holder) {
                struct se_node_acl *pr_res_nacl = pr_res_holder->pr_reg_nacl;
                __core_scsi3_complete_pro_release(dev, pr_res_nacl,
-                       pr_res_holder, 0);
+                                                 pr_res_holder, 0, 0);
        }
        spin_unlock(&dev->dev_reservation_lock);
        /*
@@ -2679,7 +2723,7 @@ static void __core_scsi3_complete_pro_preempt(
         */
        if (dev->dev_pr_res_holder)
                __core_scsi3_complete_pro_release(dev, nacl,
-                               dev->dev_pr_res_holder, 0);
+                                                 dev->dev_pr_res_holder, 0, 0);
 
        dev->dev_pr_res_holder = pr_reg;
        pr_reg->pr_res_holder = 1;
@@ -2924,8 +2968,8 @@ core_scsi3_pro_preempt(struct se_cmd *cmd, int type, int scope, u64 res_key,
         */
        if (pr_reg_n != pr_res_holder)
                __core_scsi3_complete_pro_release(dev,
-                               pr_res_holder->pr_reg_nacl,
-                               dev->dev_pr_res_holder, 0);
+                                                 pr_res_holder->pr_reg_nacl,
+                                                 dev->dev_pr_res_holder, 0, 0);
        /*
         * b) Remove the registrations for all I_T nexuses identified
         *    by the SERVICE ACTION RESERVATION KEY field, except the
@@ -3059,7 +3103,7 @@ core_scsi3_emulate_pro_register_and_move(struct se_cmd *cmd, u64 res_key,
        struct t10_reservation *pr_tmpl = &dev->t10_pr;
        unsigned char *buf;
        unsigned char *initiator_str;
-       char *iport_ptr = NULL, dest_iport[64], i_buf[PR_REG_ISID_ID_LEN];
+       char *iport_ptr = NULL, i_buf[PR_REG_ISID_ID_LEN];
        u32 tid_len, tmp_tid_len;
        int new_reg = 0, type, scope, matching_iname;
        sense_reason_t ret;
@@ -3071,7 +3115,6 @@ core_scsi3_emulate_pro_register_and_move(struct se_cmd *cmd, u64 res_key,
                return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
        }
 
-       memset(dest_iport, 0, 64);
        memset(i_buf, 0, PR_REG_ISID_ID_LEN);
        se_tpg = se_sess->se_tpg;
        tf_ops = se_tpg->se_tpg_tfo;
@@ -3389,7 +3432,7 @@ after_iport_check:
         *    holder (i.e., the I_T nexus on which the
         */
        __core_scsi3_complete_pro_release(dev, pr_res_nacl,
-                       dev->dev_pr_res_holder, 0);
+                                         dev->dev_pr_res_holder, 0, 0);
        /*
         * g) Move the persistent reservation to the specified I_T nexus using
         *    the same scope and type as the persistent reservation released in
@@ -3837,7 +3880,8 @@ core_scsi3_pri_read_full_status(struct se_cmd *cmd)
        unsigned char *buf;
        u32 add_desc_len = 0, add_len = 0, desc_len, exp_desc_len;
        u32 off = 8; /* off into first Full Status descriptor */
-       int format_code = 0;
+       int format_code = 0, pr_res_type = 0, pr_res_scope = 0;
+       bool all_reg = false;
 
        if (cmd->data_length < 8) {
                pr_err("PRIN SA READ_FULL_STATUS SCSI Data Length: %u"
@@ -3854,6 +3898,19 @@ core_scsi3_pri_read_full_status(struct se_cmd *cmd)
        buf[2] = ((dev->t10_pr.pr_generation >> 8) & 0xff);
        buf[3] = (dev->t10_pr.pr_generation & 0xff);
 
+       spin_lock(&dev->dev_reservation_lock);
+       if (dev->dev_pr_res_holder) {
+               struct t10_pr_registration *pr_holder = dev->dev_pr_res_holder;
+
+               if (pr_holder->pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_ALLREG ||
+                   pr_holder->pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_ALLREG) {
+                       all_reg = true;
+                       pr_res_type = pr_holder->pr_res_type;
+                       pr_res_scope = pr_holder->pr_res_scope;
+               }
+       }
+       spin_unlock(&dev->dev_reservation_lock);
+
        spin_lock(&pr_tmpl->registration_lock);
        list_for_each_entry_safe(pr_reg, pr_reg_tmp,
                        &pr_tmpl->registration_list, pr_reg_list) {
@@ -3901,14 +3958,20 @@ core_scsi3_pri_read_full_status(struct se_cmd *cmd)
                 * reservation holder for PR_HOLDER bit.
                 *
                 * Also, if this registration is the reservation
-                * holder, fill in SCOPE and TYPE in the next byte.
+                * holder or there is an All Registrants reservation
+                * active, fill in SCOPE and TYPE in the next byte.
                 */
                if (pr_reg->pr_res_holder) {
                        buf[off++] |= 0x01;
                        buf[off++] = (pr_reg->pr_res_scope & 0xf0) |
                                     (pr_reg->pr_res_type & 0x0f);
-               } else
+               } else if (all_reg) {
+                       buf[off++] |= 0x01;
+                       buf[off++] = (pr_res_scope & 0xf0) |
+                                    (pr_res_type & 0x0f);
+               } else {
                        off += 2;
+               }
 
                off += 4; /* Skip over reserved area */
                /*