From becd9be6069e7b183c084f460f0eb363e43cc487 Mon Sep 17 00:00:00 2001 From: Mike Christie Date: Sat, 18 Mar 2023 20:56:12 -0500 Subject: scsi: target: Move sess cmd counter to new struct iSCSI needs to wait on outstanding commands like how SRP and the FC/FCoE drivers do. It can't use target_stop_session() because for MCS support we can't stop the entire session during recovery because if other connections are OK then we want to be able to continue to execute I/O on them. Move the per session cmd counters to a new struct so iSCSI can allocate them per connection. The xcopy code can also just not allocate in the future since it doesn't need to track commands. Signed-off-by: Mike Christie Link: https://lore.kernel.org/r/20230319015620.96006-2-michael.christie@oracle.com Reviewed-by: Maurizio Lombardi Signed-off-by: Martin K. Petersen --- include/target/iscsi/iscsi_target_core.h | 1 + include/target/target_core_base.h | 13 +++++++++---- 2 files changed, 10 insertions(+), 4 deletions(-) (limited to 'include/target') diff --git a/include/target/iscsi/iscsi_target_core.h b/include/target/iscsi/iscsi_target_core.h index 94d06ddfd80a..229118156a1f 100644 --- a/include/target/iscsi/iscsi_target_core.h +++ b/include/target/iscsi/iscsi_target_core.h @@ -600,6 +600,7 @@ struct iscsit_conn { struct iscsi_tpg_np *tpg_np; /* Pointer to parent session */ struct iscsit_session *sess; + struct target_cmd_counter *cmd_cnt; int bitmap_id; int rx_thread_active; struct task_struct *rx_thread; diff --git a/include/target/target_core_base.h b/include/target/target_core_base.h index 12c9ba16217e..bd299790e99c 100644 --- a/include/target/target_core_base.h +++ b/include/target/target_core_base.h @@ -494,6 +494,7 @@ struct se_cmd { struct se_lun *se_lun; /* Only used for internal passthrough and legacy TCM fabric modules */ struct se_session *se_sess; + struct target_cmd_counter *cmd_cnt; struct se_tmr_req *se_tmr_req; struct llist_node se_cmd_list; struct completion *free_compl; @@ -619,22 +620,26 @@ static inline struct se_node_acl *fabric_stat_to_nacl(struct config_item *item) acl_fabric_stat_group); } -struct se_session { +struct target_cmd_counter { + struct percpu_ref refcnt; + wait_queue_head_t refcnt_wq; + struct completion stop_done; atomic_t stopped; +}; + +struct se_session { u64 sess_bin_isid; enum target_prot_op sup_prot_ops; enum target_prot_type sess_prot_type; struct se_node_acl *se_node_acl; struct se_portal_group *se_tpg; void *fabric_sess_ptr; - struct percpu_ref cmd_count; struct list_head sess_list; struct list_head sess_acl_list; spinlock_t sess_cmd_lock; - wait_queue_head_t cmd_count_wq; - struct completion stop_done; void *sess_cmd_map; struct sbitmap_queue sess_tag_pool; + struct target_cmd_counter *cmd_cnt; }; struct se_device; -- cgit From 4edba7e4a8f39112398d3cda94128a8e13a7d527 Mon Sep 17 00:00:00 2001 From: Mike Christie Date: Sat, 18 Mar 2023 20:56:13 -0500 Subject: scsi: target: Move cmd counter allocation iSCSI needs to allocate its cmd counter per connection for MCS support where we need to stop and wait on commands running on a connection instead of per session. This moves the cmd counter allocation to target_setup_session() which is used by drivers that need the stop+wait behavior per session. xcopy doesn't need stop+wait at all, so we will be OK moving the cmd counter allocation outside of transport_init_session(). Signed-off-by: Mike Christie Link: https://lore.kernel.org/r/20230319015620.96006-3-michael.christie@oracle.com Signed-off-by: Martin K. Petersen --- include/target/target_core_fabric.h | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'include/target') diff --git a/include/target/target_core_fabric.h b/include/target/target_core_fabric.h index 38f0662476d1..65527174b8bc 100644 --- a/include/target/target_core_fabric.h +++ b/include/target/target_core_fabric.h @@ -133,7 +133,9 @@ struct se_session *target_setup_session(struct se_portal_group *, struct se_session *, void *)); void target_remove_session(struct se_session *); -int transport_init_session(struct se_session *se_sess); +struct target_cmd_counter *target_alloc_cmd_counter(void); + +void transport_init_session(struct se_session *se_sess); struct se_session *transport_alloc_session(enum target_prot_op); int transport_alloc_session_tags(struct se_session *, unsigned int, unsigned int); -- cgit From 8e288be8606ad87c1726618eacfb8fbd3ab4b806 Mon Sep 17 00:00:00 2001 From: Mike Christie Date: Sat, 18 Mar 2023 20:56:14 -0500 Subject: scsi: target: Pass in cmd counter to use during cmd setup Allow target_get_sess_cmd() users to pass in the cmd counter they want to use. Right now we pass in the session's cmd counter but in a subsequent commit iSCSI will switch from per session to per conn. Signed-off-by: Mike Christie Link: https://lore.kernel.org/r/20230319015620.96006-4-michael.christie@oracle.com Signed-off-by: Martin K. Petersen --- include/target/target_core_fabric.h | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) (limited to 'include/target') diff --git a/include/target/target_core_fabric.h b/include/target/target_core_fabric.h index 65527174b8bc..d507e7885f17 100644 --- a/include/target/target_core_fabric.h +++ b/include/target/target_core_fabric.h @@ -151,9 +151,11 @@ void transport_deregister_session_configfs(struct se_session *); void transport_deregister_session(struct se_session *); -void __target_init_cmd(struct se_cmd *, - const struct target_core_fabric_ops *, - struct se_session *, u32, int, int, unsigned char *, u64); +void __target_init_cmd(struct se_cmd *cmd, + const struct target_core_fabric_ops *tfo, + struct se_session *sess, u32 data_length, int data_direction, + int task_attr, unsigned char *sense_buffer, u64 unpacked_lun, + struct target_cmd_counter *cmd_cnt); int target_init_cmd(struct se_cmd *se_cmd, struct se_session *se_sess, unsigned char *sense, u64 unpacked_lun, u32 data_length, int task_attr, int data_dir, int flags); -- cgit From 6d256bee602b131bd4fbc92863b6a1210bcf6325 Mon Sep 17 00:00:00 2001 From: Mike Christie Date: Sat, 18 Mar 2023 20:56:15 -0500 Subject: scsi: target: iscsit: isert: Alloc per conn cmd counter This has iscsit allocate a per conn cmd counter and converts iscsit/isert to use it instead of the per session one. Signed-off-by: Mike Christie Link: https://lore.kernel.org/r/20230319015620.96006-5-michael.christie@oracle.com Signed-off-by: Martin K. Petersen --- include/target/target_core_fabric.h | 3 +++ 1 file changed, 3 insertions(+) (limited to 'include/target') diff --git a/include/target/target_core_fabric.h b/include/target/target_core_fabric.h index d507e7885f17..b188b1e90e1e 100644 --- a/include/target/target_core_fabric.h +++ b/include/target/target_core_fabric.h @@ -133,7 +133,10 @@ struct se_session *target_setup_session(struct se_portal_group *, struct se_session *, void *)); void target_remove_session(struct se_session *); +void target_stop_cmd_counter(struct target_cmd_counter *cmd_cnt); +void target_wait_for_cmds(struct target_cmd_counter *cmd_cnt); struct target_cmd_counter *target_alloc_cmd_counter(void); +void target_free_cmd_counter(struct target_cmd_counter *cmd_cnt); void transport_init_session(struct se_session *se_sess); struct se_session *transport_alloc_session(enum target_prot_op); -- cgit From 673db054d7a2b5a470d7a25baf65956d005ad729 Mon Sep 17 00:00:00 2001 From: Mike Christie Date: Sat, 18 Mar 2023 20:56:18 -0500 Subject: scsi: target: Fix multiple LUN_RESET handling This fixes a bug where an initiator thinks a LUN_RESET has cleaned up running commands when it hasn't. The bug was added in commit 51ec502a3266 ("target: Delete tmr from list before processing"). The problem occurs when: 1. We have N I/O cmds running in the target layer spread over 2 sessions. 2. The initiator sends a LUN_RESET for each session. 3. session1's LUN_RESET loops over all the running commands from both sessions and moves them to its local drain_task_list. 4. session2's LUN_RESET does not see the LUN_RESET from session1 because the commit above has it remove itself. session2 also does not see any commands since the other reset moved them off the state lists. 5. sessions2's LUN_RESET will then complete with a successful response. 6. sessions2's inititor believes the running commands on its session are now cleaned up due to the successful response and cleans up the running commands from its side. It then restarts them. 7. The commands do eventually complete on the backend and the target starts to return aborted task statuses for them. The initiator will either throw a invalid ITT error or might accidentally lookup a new task if the ITT has been reallocated already. Fix the bug by reverting the patch, and serialize the execution of LUN_RESETs and Preempt and Aborts. Also prevent us from waiting on LUN_RESETs in core_tmr_drain_tmr_list, because it turns out the original patch fixed a bug that was not mentioned. For LUN_RESET1 core_tmr_drain_tmr_list can see a second LUN_RESET and wait on it. Then the second reset will run core_tmr_drain_tmr_list and see the first reset and wait on it resulting in a deadlock. Fixes: 51ec502a3266 ("target: Delete tmr from list before processing") Signed-off-by: Mike Christie Link: https://lore.kernel.org/r/20230319015620.96006-8-michael.christie@oracle.com Signed-off-by: Martin K. Petersen --- include/target/target_core_base.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/target') diff --git a/include/target/target_core_base.h b/include/target/target_core_base.h index bd299790e99c..8cc42ad65c92 100644 --- a/include/target/target_core_base.h +++ b/include/target/target_core_base.h @@ -872,6 +872,7 @@ struct se_device { struct rcu_head rcu_head; int queue_cnt; struct se_device_queue *queues; + struct mutex lun_reset_mutex; }; struct target_opcode_descriptor { -- cgit