Merge git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending

Pull SCSI target fixes from Nicholas Bellinger:
 "Here are the outstanding target fixes queued up for v3.12-rc4 code.

  The highlights include:

   - Make vhost/scsi tag percpu_ida_alloc() use GFP_ATOMIC
   - Allow sess_cmd_map allocation failure fallback to use vzalloc
   - Fix COMPARE_AND_WRITE se_cmd->data_length bug with FILEIO backends
   - Fixes for COMPARE_AND_WRITE callback recursive failure OOPs + non
     zero scsi_status bug
   - Make iscsi-target do acknowledgement tag release from RX context
   - Setup iscsi-target with extra (cmdsn_depth / 2) percpu_ida tags

  Also included is a iscsi-target patch CC'ed for v3.10+ that avoids
  legacy wait_for_task=true release during fast-past StatSN
  acknowledgement, and two other SRP target related patches that address
  long-standing issues that are CC'ed for v3.3+.

  Extra thanks to Thomas Glanzmann for his testing feedback with
  COMPARE_AND_WRITE + EXTENDED_COPY VAAI logic"

* git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending:
  iscsi-target; Allow an extra tag_num / 2 number of percpu_ida tags
  iscsi-target: Perform release of acknowledged tags from RX context
  iscsi-target: Only perform wait_for_tasks when performing shutdown
  target: Fail on non zero scsi_status in compare_and_write_callback
  target: Fix recursive COMPARE_AND_WRITE callback failure
  target: Reset data_length for COMPARE_AND_WRITE to NoLB * block_size
  ib_srpt: always set response for task management
  target: Fall back to vzalloc upon ->sess_cmd_map kzalloc failure
  vhost/scsi: Use GFP_ATOMIC with percpu_ida_alloc for obtaining tag
  ib_srpt: Destroy cm_id before destroying QP.
  target: Fix xop->dbl assignment in target_xcopy_parse_segdesc_02

8 files changed, 67 insertions, 25 deletions

diff --git a/drivers/infiniband/ulp/srpt/ib_srpt.c b/drivers/infiniband/ulp/srpt/ib_srpt.c
index 653ac6bfc57a..6c923c7039a1 100644
--- a/drivers/infiniband/ulp/srpt/ib_srpt.c
+++ b/drivers/infiniband/ulp/srpt/ib_srpt.c
@@ -1588,7 +1588,7 @@ static int srpt_build_tskmgmt_rsp(struct srpt_rdma_ch *ch,
         int resp_data_len;
         int resp_len;
 
-        resp_data_len = (rsp_code == SRP_TSK_MGMT_SUCCESS) ? 0 : 4;
+        resp_data_len = 4;
         resp_len = sizeof(*srp_rsp) + resp_data_len;
 
         srp_rsp = ioctx->ioctx.buf;
@@ -1600,11 +1600,9 @@ static int srpt_build_tskmgmt_rsp(struct srpt_rdma_ch *ch,
                                     + atomic_xchg(&ch->req_lim_delta, 0));
         srp_rsp->tag = tag;
 
-        if (rsp_code != SRP_TSK_MGMT_SUCCESS) {
-                srp_rsp->flags |= SRP_RSP_FLAG_RSPVALID;
-                srp_rsp->resp_data_len = cpu_to_be32(resp_data_len);
-                srp_rsp->data[3] = rsp_code;
-        }
+        srp_rsp->flags |= SRP_RSP_FLAG_RSPVALID;
+        srp_rsp->resp_data_len = cpu_to_be32(resp_data_len);
+        srp_rsp->data[3] = rsp_code;
 
         return resp_len;
 }
@@ -2358,6 +2356,8 @@ static void srpt_release_channel_work(struct work_struct *w)
         transport_deregister_session(se_sess);
         ch->sess = NULL;
 
+        ib_destroy_cm_id(ch->cm_id);
+
         srpt_destroy_ch_ib(ch);
 
         srpt_free_ioctx_ring((struct srpt_ioctx **)ch->ioctx_ring,
@@ -2368,8 +2368,6 @@ static void srpt_release_channel_work(struct work_struct *w)
         list_del(&ch->list);
         spin_unlock_irq(&sdev->spinlock);
 
-        ib_destroy_cm_id(ch->cm_id);
-
         if (ch->release_done)
                 complete(ch->release_done);
 
diff --git a/drivers/target/iscsi/iscsi_target.c b/drivers/target/iscsi/iscsi_target.c
index 35b61f7d6c63..38e44b9abf0f 100644
--- a/drivers/target/iscsi/iscsi_target.c
+++ b/drivers/target/iscsi/iscsi_target.c
@@ -753,7 +753,8 @@ static void iscsit_unmap_iovec(struct iscsi_cmd *cmd)
 
 static void iscsit_ack_from_expstatsn(struct iscsi_conn *conn, u32 exp_statsn)
 {
-        struct iscsi_cmd *cmd;
+        LIST_HEAD(ack_list);
+        struct iscsi_cmd *cmd, *cmd_p;
 
         conn->exp_statsn = exp_statsn;
 
@@ -761,19 +762,23 @@ static void iscsit_ack_from_expstatsn(struct iscsi_conn *conn, u32 exp_statsn)
                 return;
 
         spin_lock_bh(&conn->cmd_lock);
-        list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
+        list_for_each_entry_safe(cmd, cmd_p, &conn->conn_cmd_list, i_conn_node) {
                 spin_lock(&cmd->istate_lock);
                 if ((cmd->i_state == ISTATE_SENT_STATUS) &&
                     iscsi_sna_lt(cmd->stat_sn, exp_statsn)) {
                         cmd->i_state = ISTATE_REMOVE;
                         spin_unlock(&cmd->istate_lock);
-                        iscsit_add_cmd_to_immediate_queue(cmd, conn,
-                                                cmd->i_state);
+                        list_move_tail(&cmd->i_conn_node, &ack_list);
                         continue;
                 }
                 spin_unlock(&cmd->istate_lock);
         }
         spin_unlock_bh(&conn->cmd_lock);
+
+        list_for_each_entry_safe(cmd, cmd_p, &ack_list, i_conn_node) {
+                list_del(&cmd->i_conn_node);
+                iscsit_free_cmd(cmd, false);
+        }
 }
 
 static int iscsit_allocate_iovecs(struct iscsi_cmd *cmd)
diff --git a/drivers/target/iscsi/iscsi_target_nego.c b/drivers/target/iscsi/iscsi_target_nego.c
index 14d1aed5af1d..ef6d836a4d09 100644
--- a/drivers/target/iscsi/iscsi_target_nego.c
+++ b/drivers/target/iscsi/iscsi_target_nego.c
@@ -1192,7 +1192,7 @@ get_target:
          */
 alloc_tags:
         tag_num = max_t(u32, ISCSIT_MIN_TAGS, queue_depth);
-        tag_num += ISCSIT_EXTRA_TAGS;
+        tag_num += (tag_num / 2) + ISCSIT_EXTRA_TAGS;
         tag_size = sizeof(struct iscsi_cmd) + conn->conn_transport->priv_size;
 
         ret = transport_alloc_session_tags(sess->se_sess, tag_num, tag_size);
diff --git a/drivers/target/iscsi/iscsi_target_util.c b/drivers/target/iscsi/iscsi_target_util.c
index f2de28e178fd..b0cac0c342e1 100644
--- a/drivers/target/iscsi/iscsi_target_util.c
+++ b/drivers/target/iscsi/iscsi_target_util.c
@@ -736,7 +736,7 @@ void iscsit_free_cmd(struct iscsi_cmd *cmd, bool shutdown)
                  * Fallthrough
                  */
         case ISCSI_OP_SCSI_TMFUNC:
-                rc = transport_generic_free_cmd(&cmd->se_cmd, 1);
+                rc = transport_generic_free_cmd(&cmd->se_cmd, shutdown);
                 if (!rc && shutdown && se_cmd && se_cmd->se_sess) {
                         __iscsit_free_cmd(cmd, true, shutdown);
                         target_put_sess_cmd(se_cmd->se_sess, se_cmd);
@@ -752,7 +752,7 @@ void iscsit_free_cmd(struct iscsi_cmd *cmd, bool shutdown)
                         se_cmd = &cmd->se_cmd;
                         __iscsit_free_cmd(cmd, true, shutdown);
 
-                        rc = transport_generic_free_cmd(&cmd->se_cmd, 1);
+                        rc = transport_generic_free_cmd(&cmd->se_cmd, shutdown);
                         if (!rc && shutdown && se_cmd->se_sess) {
                                 __iscsit_free_cmd(cmd, true, shutdown);
                                 target_put_sess_cmd(se_cmd->se_sess, se_cmd);
diff --git a/drivers/target/target_core_sbc.c b/drivers/target/target_core_sbc.c
index 6c17295e8d7c..4714c6f8da4b 100644
--- a/drivers/target/target_core_sbc.c
+++ b/drivers/target/target_core_sbc.c
@@ -349,7 +349,16 @@ static sense_reason_t compare_and_write_post(struct se_cmd *cmd)
 {
         struct se_device *dev = cmd->se_dev;
 
-        cmd->se_cmd_flags |= SCF_COMPARE_AND_WRITE_POST;
+        /*
+         * Only set SCF_COMPARE_AND_WRITE_POST to force a response fall-through
+         * within target_complete_ok_work() if the command was successfully
+         * sent to the backend driver.
+         */
+        spin_lock_irq(&cmd->t_state_lock);
+        if ((cmd->transport_state & CMD_T_SENT) && !cmd->scsi_status)
+                cmd->se_cmd_flags |= SCF_COMPARE_AND_WRITE_POST;
+        spin_unlock_irq(&cmd->t_state_lock);
+
         /*
          * Unlock ->caw_sem originally obtained during sbc_compare_and_write()
          * before the original READ I/O submission.
@@ -363,7 +372,7 @@ static sense_reason_t compare_and_write_callback(struct se_cmd *cmd)
 {
         struct se_device *dev = cmd->se_dev;
         struct scatterlist *write_sg = NULL, *sg;
-        unsigned char *buf, *addr;
+        unsigned char *buf = NULL, *addr;
         struct sg_mapping_iter m;
         unsigned int offset = 0, len;
         unsigned int nlbas = cmd->t_task_nolb;
@@ -378,6 +387,15 @@ static sense_reason_t compare_and_write_callback(struct se_cmd *cmd)
          */
         if (!cmd->t_data_sg || !cmd->t_bidi_data_sg)
                 return TCM_NO_SENSE;
+        /*
+         * Immediately exit + release dev->caw_sem if command has already
+         * been failed with a non-zero SCSI status.
+         */
+        if (cmd->scsi_status) {
+                pr_err("compare_and_write_callback: non zero scsi_status:"
+                        " 0x%02x\n", cmd->scsi_status);
+                goto out;
+        }
 
         buf = kzalloc(cmd->data_length, GFP_KERNEL);
         if (!buf) {
@@ -508,6 +526,12 @@ sbc_compare_and_write(struct se_cmd *cmd)
                 cmd->transport_complete_callback = NULL;
                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
         }
+        /*
+         * Reset cmd->data_length to individual block_size in order to not
+         * confuse backend drivers that depend on this value matching the
+         * size of the I/O being submitted.
+         */
+        cmd->data_length = cmd->t_task_nolb * dev->dev_attrib.block_size;
 
         ret = cmd->execute_rw(cmd, cmd->t_bidi_data_sg, cmd->t_bidi_data_nents,
                               DMA_FROM_DEVICE);
diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c
index 84747cc1aac0..81e945eefbbd 100644
--- a/drivers/target/target_core_transport.c
+++ b/drivers/target/target_core_transport.c
@@ -236,17 +236,24 @@ int transport_alloc_session_tags(struct se_session *se_sess,
 {
         int rc;
 
-        se_sess->sess_cmd_map = kzalloc(tag_num * tag_size, GFP_KERNEL);
+        se_sess->sess_cmd_map = kzalloc(tag_num * tag_size,
+                                        GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
         if (!se_sess->sess_cmd_map) {
-                pr_err("Unable to allocate se_sess->sess_cmd_map\n");
-                return -ENOMEM;
+                se_sess->sess_cmd_map = vzalloc(tag_num * tag_size);
+                if (!se_sess->sess_cmd_map) {
+                        pr_err("Unable to allocate se_sess->sess_cmd_map\n");
+                        return -ENOMEM;
+                }
         }
 
         rc = percpu_ida_init(&se_sess->sess_tag_pool, tag_num);
         if (rc < 0) {
                 pr_err("Unable to init se_sess->sess_tag_pool,"
                         " tag_num: %u\n", tag_num);
-                kfree(se_sess->sess_cmd_map);
+                if (is_vmalloc_addr(se_sess->sess_cmd_map))
+                        vfree(se_sess->sess_cmd_map);
+                else
+                        kfree(se_sess->sess_cmd_map);
                 se_sess->sess_cmd_map = NULL;
                 return -ENOMEM;
         }
@@ -412,7 +419,10 @@ void transport_free_session(struct se_session *se_sess)
 {
         if (se_sess->sess_cmd_map) {
                 percpu_ida_destroy(&se_sess->sess_tag_pool);
-                kfree(se_sess->sess_cmd_map);
+                if (is_vmalloc_addr(se_sess->sess_cmd_map))
+                        vfree(se_sess->sess_cmd_map);
+                else
+                        kfree(se_sess->sess_cmd_map);
         }
         kmem_cache_free(se_sess_cache, se_sess);
 }
diff --git a/drivers/target/target_core_xcopy.c b/drivers/target/target_core_xcopy.c
index 4d22e7d2adca..3da4fd10b9f8 100644
--- a/drivers/target/target_core_xcopy.c
+++ b/drivers/target/target_core_xcopy.c
@@ -298,8 +298,8 @@ static int target_xcopy_parse_segdesc_02(struct se_cmd *se_cmd, struct xcopy_op
                 (unsigned long long)xop->dst_lba);
 
         if (dc != 0) {
-                xop->dbl = (desc[29] << 16) & 0xff;
-                xop->dbl |= (desc[30] << 8) & 0xff;
+                xop->dbl = (desc[29] & 0xff) << 16;
+                xop->dbl |= (desc[30] & 0xff) << 8;
                 xop->dbl |= desc[31] & 0xff;
 
                 pr_debug("XCOPY seg desc 0x02: DC=1 w/ dbl: %u\n", xop->dbl);
diff --git a/drivers/vhost/scsi.c b/drivers/vhost/scsi.c
index 592b31698fc8..ce5221fa393a 100644
--- a/drivers/vhost/scsi.c
+++ b/drivers/vhost/scsi.c
@@ -728,7 +728,12 @@ vhost_scsi_get_tag(struct vhost_virtqueue *vq,
         }
         se_sess = tv_nexus->tvn_se_sess;
 
-        tag = percpu_ida_alloc(&se_sess->sess_tag_pool, GFP_KERNEL);
+        tag = percpu_ida_alloc(&se_sess->sess_tag_pool, GFP_ATOMIC);
+        if (tag < 0) {
+                pr_err("Unable to obtain tag for tcm_vhost_cmd\n");
+                return ERR_PTR(-ENOMEM);
+        }
+
         cmd = &((struct tcm_vhost_cmd *)se_sess->sess_cmd_map)[tag];
         sg = cmd->tvc_sgl;
         pages = cmd->tvc_upages;