From 79dc9c9e865a7f8c14737453f112ced25deafdef Mon Sep 17 00:00:00 2001 From: Nicholas Bellinger Date: Fri, 27 Mar 2015 04:51:03 +0000 Subject: [PATCH] target/pr: Change alloc_registration to avoid pr_reg_tg_pt_lun This patch changes __core_scsi3_do_alloc_registration() code to drop pr_reg->pr_reg_tg_pt_lun pointer usage in favor of a new pr_reg RPTI + existing pr_reg->pr_aptpl_target_lun used by APTPL metadata logic. It also includes changes to REGISTER, REGISTER_AND_MOVE and APTPL feature bit codepaths to use rcu_dereference_check() with the expected non-zero se_dev_entry->pr_kref reference held. Reviewed-by: Hannes Reinecke Cc: Christoph Hellwig Cc: Sagi Grimberg Signed-off-by: Nicholas Bellinger --- drivers/target/target_core_configfs.c | 6 +- drivers/target/target_core_pr.c | 131 +++++++++++++------------- include/target/target_core_base.h | 4 +- 3 files changed, 72 insertions(+), 69 deletions(-) diff --git a/drivers/target/target_core_configfs.c b/drivers/target/target_core_configfs.c index 798386a1b6e7..4a31d4765390 100644 --- a/drivers/target/target_core_configfs.c +++ b/drivers/target/target_core_configfs.c @@ -817,7 +817,6 @@ static ssize_t target_core_dev_pr_show_attr_res_pr_holder_tg_port( struct se_device *dev, char *page) { struct se_node_acl *se_nacl; - struct se_lun *lun; struct se_portal_group *se_tpg; struct t10_pr_registration *pr_reg; const struct target_core_fabric_ops *tfo; @@ -832,7 +831,6 @@ static ssize_t target_core_dev_pr_show_attr_res_pr_holder_tg_port( se_nacl = pr_reg->pr_reg_nacl; se_tpg = se_nacl->se_tpg; - lun = pr_reg->pr_reg_tg_pt_lun; tfo = se_tpg->se_tpg_tfo; len += sprintf(page+len, "SPC-3 Reservation: %s" @@ -840,9 +838,9 @@ static ssize_t target_core_dev_pr_show_attr_res_pr_holder_tg_port( tfo->tpg_get_wwn(se_tpg)); len += sprintf(page+len, "SPC-3 Reservation: Relative Port" " Identifier Tag: %hu %s Portal Group Tag: %hu" - " %s Logical Unit: %u\n", lun->lun_sep->sep_rtpi, + " %s Logical Unit: %u\n", pr_reg->tg_pt_sep_rtpi, tfo->get_fabric_name(), tfo->tpg_get_tag(se_tpg), - tfo->get_fabric_name(), lun->unpacked_lun); + tfo->get_fabric_name(), pr_reg->pr_aptpl_target_lun); out_unlock: spin_unlock(&dev->dev_reservation_lock); diff --git a/drivers/target/target_core_pr.c b/drivers/target/target_core_pr.c index 66e686bdf894..48ed5d2bf5fe 100644 --- a/drivers/target/target_core_pr.c +++ b/drivers/target/target_core_pr.c @@ -44,11 +44,10 @@ * Used for Specify Initiator Ports Capable Bit (SPEC_I_PT) */ struct pr_transport_id_holder { - int dest_local_nexus; struct t10_pr_registration *dest_pr_reg; struct se_portal_group *dest_tpg; struct se_node_acl *dest_node_acl; - struct se_dev_entry __rcu *dest_se_deve; + struct se_dev_entry *dest_se_deve; struct list_head dest_list; }; @@ -625,7 +624,9 @@ static u32 core_scsi3_pr_generation(struct se_device *dev) static struct t10_pr_registration *__core_scsi3_do_alloc_registration( struct se_device *dev, struct se_node_acl *nacl, + struct se_lun *lun, struct se_dev_entry *deve, + u32 mapped_lun, unsigned char *isid, u64 sa_res_key, int all_tg_pt, @@ -647,12 +648,12 @@ static struct t10_pr_registration *__core_scsi3_do_alloc_registration( atomic_set(&pr_reg->pr_res_holders, 0); pr_reg->pr_reg_nacl = nacl; pr_reg->pr_reg_deve = deve; - pr_reg->pr_res_mapped_lun = deve->mapped_lun; - pr_reg->pr_aptpl_target_lun = deve->se_lun->unpacked_lun; + pr_reg->pr_res_mapped_lun = mapped_lun; + pr_reg->pr_aptpl_target_lun = lun->unpacked_lun; + pr_reg->tg_pt_sep_rtpi = lun->lun_sep->sep_rtpi; pr_reg->pr_res_key = sa_res_key; pr_reg->pr_reg_all_tg_pt = all_tg_pt; pr_reg->pr_reg_aptpl = aptpl; - pr_reg->pr_reg_tg_pt_lun = deve->se_lun; /* * If an ISID value for this SCSI Initiator Port exists, * save it to the registration now. @@ -676,7 +677,9 @@ static void core_scsi3_lunacl_undepend_item(struct se_dev_entry *); static struct t10_pr_registration *__core_scsi3_alloc_registration( struct se_device *dev, struct se_node_acl *nacl, + struct se_lun *lun, struct se_dev_entry *deve, + u32 mapped_lun, unsigned char *isid, u64 sa_res_key, int all_tg_pt, @@ -684,6 +687,8 @@ static struct t10_pr_registration *__core_scsi3_alloc_registration( { struct se_dev_entry *deve_tmp; struct se_node_acl *nacl_tmp; + struct se_lun_acl *lacl_tmp; + struct se_lun *lun_tmp; struct se_port *port, *port_tmp; const struct target_core_fabric_ops *tfo = nacl->se_tpg->se_tpg_tfo; struct t10_pr_registration *pr_reg, *pr_reg_atp, *pr_reg_tmp, *pr_reg_tmp_safe; @@ -692,8 +697,9 @@ static struct t10_pr_registration *__core_scsi3_alloc_registration( * Create a registration for the I_T Nexus upon which the * PROUT REGISTER was received. */ - pr_reg = __core_scsi3_do_alloc_registration(dev, nacl, deve, isid, - sa_res_key, all_tg_pt, aptpl); + pr_reg = __core_scsi3_do_alloc_registration(dev, nacl, lun, deve, mapped_lun, + isid, sa_res_key, all_tg_pt, + aptpl); if (!pr_reg) return NULL; /* @@ -721,7 +727,9 @@ static struct t10_pr_registration *__core_scsi3_alloc_registration( if (!deve_tmp->se_lun_acl) continue; - nacl_tmp = deve_tmp->se_lun_acl->se_lun_nacl; + lacl_tmp = rcu_dereference_check(deve_tmp->se_lun_acl, + lockdep_is_held(&port->sep_alua_lock)); + nacl_tmp = lacl_tmp->se_lun_nacl; /* * Skip the matching struct se_node_acl that is allocated * above.. @@ -764,8 +772,12 @@ static struct t10_pr_registration *__core_scsi3_alloc_registration( * the original *pr_reg is processed in * __core_scsi3_add_registration() */ + lun_tmp = rcu_dereference_check(deve_tmp->se_lun, + atomic_read(&deve_tmp->pr_kref.refcount) != 0); + pr_reg_atp = __core_scsi3_do_alloc_registration(dev, - nacl_tmp, deve_tmp, NULL, + nacl_tmp, lun_tmp, deve_tmp, + deve_tmp->mapped_lun, NULL, sa_res_key, all_tg_pt, aptpl); if (!pr_reg_atp) { atomic_dec_mb(&port->sep_tg_pt_ref_cnt); @@ -835,7 +847,6 @@ int core_scsi3_alloc_aptpl_registration( pr_reg->pr_res_key = sa_res_key; pr_reg->pr_reg_all_tg_pt = all_tg_pt; pr_reg->pr_reg_aptpl = 1; - pr_reg->pr_reg_tg_pt_lun = NULL; pr_reg->pr_res_scope = 0; /* Always LUN_SCOPE */ pr_reg->pr_res_type = type; /* @@ -935,7 +946,7 @@ static int __core_scsi3_check_aptpl_registration( (pr_reg->pr_aptpl_target_lun == target_lun)) { pr_reg->pr_reg_nacl = nacl; - pr_reg->pr_reg_tg_pt_lun = lun; + pr_reg->tg_pt_sep_rtpi = lun->lun_sep->sep_rtpi; list_del(&pr_reg->pr_reg_aptpl_list); spin_unlock(&pr_tmpl->aptpl_reg_lock); @@ -1090,7 +1101,9 @@ static void __core_scsi3_add_registration( static int core_scsi3_alloc_registration( struct se_device *dev, struct se_node_acl *nacl, + struct se_lun *lun, struct se_dev_entry *deve, + u32 mapped_lun, unsigned char *isid, u64 sa_res_key, int all_tg_pt, @@ -1100,8 +1113,9 @@ static int core_scsi3_alloc_registration( { struct t10_pr_registration *pr_reg; - pr_reg = __core_scsi3_alloc_registration(dev, nacl, deve, isid, - sa_res_key, all_tg_pt, aptpl); + pr_reg = __core_scsi3_alloc_registration(dev, nacl, lun, deve, mapped_lun, + isid, sa_res_key, all_tg_pt, + aptpl); if (!pr_reg) return -EPERM; @@ -1411,12 +1425,14 @@ static void core_scsi3_nodeacl_undepend_item(struct se_node_acl *nacl) static int core_scsi3_lunacl_depend_item(struct se_dev_entry *se_deve) { - struct se_lun_acl *lun_acl = se_deve->se_lun_acl; + struct se_lun_acl *lun_acl; struct se_node_acl *nacl; struct se_portal_group *tpg; /* * For nacl->dynamic_node_acl=1 */ + lun_acl = rcu_dereference_check(se_deve->se_lun_acl, + atomic_read(&se_deve->pr_kref.refcount) != 0); if (!lun_acl) return 0; @@ -1434,7 +1450,8 @@ static void core_scsi3_lunacl_undepend_item(struct se_dev_entry *se_deve) /* * For nacl->dynamic_node_acl=1 */ - lun_acl = se_deve->se_lun_acl; + lun_acl = rcu_dereference_check(se_deve->se_lun_acl, + atomic_read(&se_deve->pr_kref.refcount) != 0); if (!lun_acl) { kref_put(&se_deve->pr_kref, target_pr_kref_release); return; @@ -1450,7 +1467,6 @@ static sense_reason_t core_scsi3_decode_spec_i_port( struct se_cmd *cmd, struct se_portal_group *tpg, - struct se_dev_entry *local_se_deve, unsigned char *l_isid, u64 sa_res_key, int all_tg_pt, @@ -1461,7 +1477,7 @@ core_scsi3_decode_spec_i_port( struct se_portal_group *dest_tpg = NULL, *tmp_tpg; struct se_session *se_sess = cmd->se_sess; struct se_node_acl *dest_node_acl = NULL; - struct se_dev_entry __rcu *dest_se_deve = NULL; + struct se_dev_entry *dest_se_deve = NULL; struct t10_pr_registration *dest_pr_reg, *local_pr_reg, *pr_reg_e; struct t10_pr_registration *pr_reg_tmp, *pr_reg_tmp_safe; LIST_HEAD(tid_dest_list); @@ -1471,14 +1487,12 @@ core_scsi3_decode_spec_i_port( 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; /* * Allocate a struct pr_transport_id_holder and setup the - * local_node_acl and local_se_deve pointers and add to - * struct list_head tid_dest_list for add registration - * processing in the loop of tid_dest_list below. + * local_node_acl pointer and add to struct list_head tid_dest_list + * for add registration processing in the loop of tid_dest_list below. */ tidh_new = kzalloc(sizeof(struct pr_transport_id_holder), GFP_KERNEL); if (!tidh_new) { @@ -1490,20 +1504,20 @@ core_scsi3_decode_spec_i_port( tidh_new->dest_node_acl = se_sess->se_node_acl; local_pr_reg = __core_scsi3_alloc_registration(cmd->se_dev, - se_sess->se_node_acl, local_se_deve, l_isid, + se_sess->se_node_acl, cmd->se_lun, + NULL, cmd->orig_fe_lun, l_isid, sa_res_key, all_tg_pt, aptpl); if (!local_pr_reg) { kfree(tidh_new); return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; } - rcu_assign_pointer(tidh_new->dest_se_deve, local_se_deve); tidh_new->dest_pr_reg = local_pr_reg; /* * The local I_T nexus does not hold any configfs dependances, - * so we set tid_h->dest_local_nexus=1 to prevent the + * so we set tidh_new->dest_se_deve to NULL to prevent the * configfs_undepend_item() calls in the tid_dest_list loops below. */ - tidh_new->dest_local_nexus = 1; + tidh_new->dest_se_deve = NULL; list_add_tail(&tidh_new->dest_list, &tid_dest_list); if (cmd->data_length < 28) { @@ -1544,6 +1558,8 @@ core_scsi3_decode_spec_i_port( ptr = &buf[28]; while (tpdl > 0) { + struct se_lun *dest_lun; + proto_ident = (ptr[0] & 0x0f); dest_tpg = NULL; @@ -1720,9 +1736,13 @@ core_scsi3_decode_spec_i_port( * and then call __core_scsi3_add_registration() in the * 2nd loop which will never fail. */ + dest_lun = rcu_dereference_check(dest_se_deve->se_lun, + atomic_read(&dest_se_deve->pr_kref.refcount) != 0); + dest_pr_reg = __core_scsi3_alloc_registration(cmd->se_dev, - dest_node_acl, dest_se_deve, iport_ptr, - sa_res_key, all_tg_pt, aptpl); + dest_node_acl, dest_lun, dest_se_deve, + dest_se_deve->mapped_lun, iport_ptr, + sa_res_key, all_tg_pt, aptpl); if (!dest_pr_reg) { core_scsi3_lunacl_undepend_item(dest_se_deve); core_scsi3_nodeacl_undepend_item(dest_node_acl); @@ -1760,7 +1780,6 @@ core_scsi3_decode_spec_i_port( dest_node_acl = tidh->dest_node_acl; dest_se_deve = tidh->dest_se_deve; dest_pr_reg = tidh->dest_pr_reg; - dest_local_nexus = tidh->dest_local_nexus; list_del(&tidh->dest_list); kfree(tidh); @@ -1774,9 +1793,10 @@ core_scsi3_decode_spec_i_port( pr_debug("SPC-3 PR [%s] SPEC_I_PT: Successfully" " registered Transport ID for Node: %s%s Mapped LUN:" " %u\n", dest_tpg->se_tpg_tfo->get_fabric_name(), - dest_node_acl->initiatorname, i_buf, dest_se_deve->mapped_lun); + dest_node_acl->initiatorname, i_buf, (dest_se_deve) ? + dest_se_deve->mapped_lun : 0); - if (dest_local_nexus) + if (!dest_se_deve) continue; core_scsi3_lunacl_undepend_item(dest_se_deve); @@ -1797,7 +1817,6 @@ out: dest_node_acl = tidh->dest_node_acl; dest_se_deve = tidh->dest_se_deve; dest_pr_reg = tidh->dest_pr_reg; - dest_local_nexus = tidh->dest_local_nexus; list_del(&tidh->dest_list); kfree(tidh); @@ -1815,7 +1834,7 @@ out: kmem_cache_free(t10_pr_reg_cache, dest_pr_reg); - if (dest_local_nexus) + if (!dest_se_deve) continue; core_scsi3_lunacl_undepend_item(dest_se_deve); @@ -1830,7 +1849,6 @@ static int core_scsi3_update_aptpl_buf( unsigned char *buf, u32 pr_aptpl_buf_len) { - struct se_lun *lun; struct se_portal_group *tpg; struct t10_pr_registration *pr_reg; unsigned char tmp[512], isid_buf[32]; @@ -1849,7 +1867,6 @@ static int core_scsi3_update_aptpl_buf( tmp[0] = '\0'; isid_buf[0] = '\0'; tpg = pr_reg->pr_reg_nacl->se_tpg; - lun = pr_reg->pr_reg_tg_pt_lun; /* * Write out any ISID value to APTPL metadata that was included * in the original registration. @@ -1901,7 +1918,8 @@ static int core_scsi3_update_aptpl_buf( " %d\n", tpg->se_tpg_tfo->get_fabric_name(), tpg->se_tpg_tfo->tpg_get_wwn(tpg), tpg->se_tpg_tfo->tpg_get_tag(tpg), - lun->lun_sep->sep_rtpi, lun->unpacked_lun, reg_count); + pr_reg->tg_pt_sep_rtpi, pr_reg->pr_aptpl_target_lun, + reg_count); if ((len + strlen(tmp) >= pr_aptpl_buf_len)) { pr_err("Unable to update renaming APTPL metadata," @@ -2011,9 +2029,7 @@ core_scsi3_emulate_pro_register(struct se_cmd *cmd, u64 res_key, u64 sa_res_key, bool aptpl, bool all_tg_pt, bool spec_i_pt, enum register_type register_type) { struct se_session *se_sess = cmd->se_sess; - struct se_node_acl *nacl = se_sess->se_node_acl; struct se_device *dev = cmd->se_dev; - struct se_dev_entry *se_deve; struct se_lun *se_lun = cmd->se_lun; struct se_portal_group *se_tpg; struct t10_pr_registration *pr_reg, *pr_reg_p, *pr_reg_tmp; @@ -2028,14 +2044,6 @@ core_scsi3_emulate_pro_register(struct se_cmd *cmd, u64 res_key, u64 sa_res_key, } se_tpg = se_sess->se_tpg; - rcu_read_lock(); - se_deve = target_nacl_find_deve(nacl, cmd->orig_fe_lun); - if (!se_deve) { - pr_err("Unable to locate se_deve for PRO-REGISTER\n"); - rcu_read_unlock(); - return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; - } - if (se_tpg->se_tpg_tfo->sess_get_initiator_sid) { memset(&isid_buf[0], 0, PR_REG_ISID_LEN); se_tpg->se_tpg_tfo->sess_get_initiator_sid(se_sess, &isid_buf[0], @@ -2050,16 +2058,14 @@ core_scsi3_emulate_pro_register(struct se_cmd *cmd, u64 res_key, u64 sa_res_key, if (res_key) { pr_warn("SPC-3 PR: Reservation Key non-zero" " for SA REGISTER, returning CONFLICT\n"); - rcu_read_unlock(); return TCM_RESERVATION_CONFLICT; } /* * Do nothing but return GOOD status. */ - if (!sa_res_key) { - rcu_read_unlock(); + if (!sa_res_key) return 0; - } + if (!spec_i_pt) { /* * Perform the Service Action REGISTER on the Initiator @@ -2067,12 +2073,12 @@ core_scsi3_emulate_pro_register(struct se_cmd *cmd, u64 res_key, u64 sa_res_key, * Logical Unit of the SCSI device server. */ if (core_scsi3_alloc_registration(cmd->se_dev, - se_sess->se_node_acl, se_deve, isid_ptr, + se_sess->se_node_acl, cmd->se_lun, + NULL, cmd->orig_fe_lun, isid_ptr, sa_res_key, all_tg_pt, aptpl, register_type, 0)) { pr_err("Unable to allocate" " struct t10_pr_registration\n"); - rcu_read_unlock(); return TCM_INVALID_PARAMETER_LIST; } } else { @@ -2084,17 +2090,13 @@ core_scsi3_emulate_pro_register(struct se_cmd *cmd, u64 res_key, u64 sa_res_key, * logic from of core_scsi3_alloc_registration() for * each TransportID provided SCSI Initiator Port/Device */ - ret = core_scsi3_decode_spec_i_port(cmd, se_tpg, se_deve, + ret = core_scsi3_decode_spec_i_port(cmd, se_tpg, isid_ptr, sa_res_key, all_tg_pt, aptpl); - if (ret != 0) { - rcu_read_unlock(); + if (ret != 0) return ret; - } } - rcu_read_unlock(); return core_scsi3_update_and_write_aptpl(dev, aptpl); } - rcu_read_unlock(); /* ok, existing registration */ @@ -3440,10 +3442,13 @@ after_iport_check: dest_pr_reg = __core_scsi3_locate_pr_reg(dev, dest_node_acl, iport_ptr); if (!dest_pr_reg) { + struct se_lun *dest_lun = rcu_dereference_check(dest_se_deve->se_lun, + atomic_read(&dest_se_deve->pr_kref.refcount) != 0); + spin_unlock(&dev->dev_reservation_lock); - if (core_scsi3_alloc_registration(cmd->se_dev, - dest_node_acl, dest_se_deve, iport_ptr, - sa_res_key, 0, aptpl, 2, 1)) { + if (core_scsi3_alloc_registration(cmd->se_dev, dest_node_acl, + dest_lun, dest_se_deve, dest_se_deve->mapped_lun, + iport_ptr, sa_res_key, 0, aptpl, 2, 1)) { ret = TCM_INVALID_PARAMETER_LIST; goto out; } @@ -4011,10 +4016,10 @@ core_scsi3_pri_read_full_status(struct se_cmd *cmd) * IDENTIFIER field are not defined by this standard. */ if (!pr_reg->pr_reg_all_tg_pt) { - struct se_port *port = pr_reg->pr_reg_tg_pt_lun->lun_sep; + u16 sep_rtpi = pr_reg->tg_pt_sep_rtpi; - buf[off++] = ((port->sep_rtpi >> 8) & 0xff); - buf[off++] = (port->sep_rtpi & 0xff); + buf[off++] = ((sep_rtpi >> 8) & 0xff); + buf[off++] = (sep_rtpi & 0xff); } else off += 2; /* Skip over RELATIVE TARGET PORT IDENTIFIER */ diff --git a/include/target/target_core_base.h b/include/target/target_core_base.h index 508528a5e927..cf3c6addf05a 100644 --- a/include/target/target_core_base.h +++ b/include/target/target_core_base.h @@ -372,13 +372,14 @@ struct t10_pr_registration { bool isid_present_at_reg; u32 pr_res_mapped_lun; u32 pr_aptpl_target_lun; + u16 tg_pt_sep_rtpi; u32 pr_res_generation; u64 pr_reg_bin_isid; u64 pr_res_key; atomic_t pr_res_holders; struct se_node_acl *pr_reg_nacl; + /* Used by ALL_TG_PT=1 registration with deve->pr_ref taken */ struct se_dev_entry *pr_reg_deve; - struct se_lun *pr_reg_tg_pt_lun; struct list_head pr_reg_list; struct list_head pr_reg_abort_list; struct list_head pr_reg_aptpl_list; @@ -498,7 +499,6 @@ struct se_cmd { struct list_head se_delayed_node; struct list_head se_qf_node; struct se_device *se_dev; - struct se_dev_entry *se_deve; struct se_lun *se_lun; /* Only used for internal passthrough and legacy TCM fabric modules */ struct se_session *se_sess; -- 2.20.1