scsi: hisi_sas: allocate slot buffer earlier

Currently we allocate the slot's memory buffer after allocating the DQ
slot.

To aid DQ lockout reduction, and allow slots to be built in parallel,
move this step (which can fail) prior to allocating the slot.

Also a stray spin_unlock_irqrestore() is removed from internal task exec
function.

Signed-off-by: Xiang Chen <chenxiang66@hisilicon.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/scsi/hisi_sas/hisi_sas_main.c b/drivers/scsi/hisi_sas/hisi_sas_main.c
index 2772e920572d2657d3583616ad3b39984987ff52..58cbe1f0e0b6fc136957cf832e2c14dee2c1d281 100644 (file)
--- a/drivers/scsi/hisi_sas/hisi_sas_main.c
+++ b/drivers/scsi/hisi_sas/hisi_sas_main.c
@@ -412,14 +412,22 @@ static int hisi_sas_task_prep(struct sas_task *task, struct hisi_sas_dq
        if (rc)
                goto err_out_dma_unmap;
 
+       slot = &hisi_hba->slot_info[slot_idx];
+       memset(slot, 0, sizeof(struct hisi_sas_slot));
+
+       slot->buf = dma_pool_alloc(hisi_hba->buffer_pool,
+                                  GFP_ATOMIC, &slot->buf_dma);
+       if (!slot->buf) {
+               rc = -ENOMEM;
+               goto err_out_tag;
+       }
+
        rc = hisi_hba->hw->get_free_slot(hisi_hba, dq);
        if (rc)
-               goto err_out_tag;
+               goto err_out_buf;
 
        dlvry_queue = dq->id;
        dlvry_queue_slot = dq->wr_point;
-       slot = &hisi_hba->slot_info[slot_idx];
-       memset(slot, 0, sizeof(struct hisi_sas_slot));
 
        slot->idx = slot_idx;
        slot->n_elem = n_elem;
@@ -434,12 +442,6 @@ static int hisi_sas_task_prep(struct sas_task *task, struct hisi_sas_dq
        task->lldd_task = slot;
        INIT_WORK(&slot->abort_slot, hisi_sas_slot_abort);
 
-       slot->buf = dma_pool_alloc(hisi_hba->buffer_pool,
-                                  GFP_ATOMIC, &slot->buf_dma);
-       if (!slot->buf) {
-               rc = -ENOMEM;
-               goto err_out_slot_buf;
-       }
        memset(slot->cmd_hdr, 0, sizeof(struct hisi_sas_cmd_hdr));
        memset(hisi_sas_cmd_hdr_addr_mem(slot), 0, HISI_SAS_COMMAND_TABLE_SZ);
        memset(hisi_sas_status_buf_addr_mem(slot), 0, HISI_SAS_STATUS_BUF_SZ);
@@ -474,8 +476,9 @@ static int hisi_sas_task_prep(struct sas_task *task, struct hisi_sas_dq
 
        return 0;
 
-err_out_slot_buf:
-       /* Nothing to be done */
+err_out_buf:
+       dma_pool_free(hisi_hba->buffer_pool, slot->buf,
+                     slot->buf_dma);
 err_out_tag:
        spin_lock_irqsave(&hisi_hba->lock, flags);
        hisi_sas_slot_index_free(hisi_hba, slot_idx);
@@ -1519,17 +1522,26 @@ hisi_sas_internal_abort_task_exec(struct hisi_hba *hisi_hba, int device_id,
        }
        spin_unlock_irqrestore(&hisi_hba->lock, flags);
 
+       slot = &hisi_hba->slot_info[slot_idx];
+       memset(slot, 0, sizeof(struct hisi_sas_slot));
+
+       slot->buf = dma_pool_alloc(hisi_hba->buffer_pool,
+                       GFP_ATOMIC, &slot->buf_dma);
+       if (!slot->buf) {
+               rc = -ENOMEM;
+               goto err_out_tag;
+       }
        spin_lock_irqsave(&dq->lock, flags_dq);
        rc = hisi_hba->hw->get_free_slot(hisi_hba, dq);
-       if (rc)
-               goto err_out_tag;
+       if (rc) {
+               rc = -ENOMEM;
+               spin_unlock_irqrestore(&dq->lock, flags_dq);
+               goto err_out_buf;
+       }
 
        dlvry_queue = dq->id;
        dlvry_queue_slot = dq->wr_point;
 
-       slot = &hisi_hba->slot_info[slot_idx];
-       memset(slot, 0, sizeof(struct hisi_sas_slot));
-
        slot->idx = slot_idx;
        slot->n_elem = n_elem;
        slot->dlvry_queue = dlvry_queue;
@@ -1541,13 +1553,6 @@ hisi_sas_internal_abort_task_exec(struct hisi_hba *hisi_hba, int device_id,
        slot->is_internal = true;
        task->lldd_task = slot;
 
-       slot->buf = dma_pool_alloc(hisi_hba->buffer_pool,
-                       GFP_ATOMIC, &slot->buf_dma);
-       if (!slot->buf) {
-               rc = -ENOMEM;
-               goto err_out_tag;
-       }
-
        memset(slot->cmd_hdr, 0, sizeof(struct hisi_sas_cmd_hdr));
        memset(hisi_sas_cmd_hdr_addr_mem(slot), 0, HISI_SAS_COMMAND_TABLE_SZ);
        memset(hisi_sas_status_buf_addr_mem(slot), 0, HISI_SAS_STATUS_BUF_SZ);
@@ -1570,11 +1575,13 @@ hisi_sas_internal_abort_task_exec(struct hisi_hba *hisi_hba, int device_id,
 
        return 0;
 
+err_out_buf:
+       dma_pool_free(hisi_hba->buffer_pool, slot->buf,
+                     slot->buf_dma);
 err_out_tag:
        spin_lock_irqsave(&hisi_hba->lock, flags);
        hisi_sas_slot_index_free(hisi_hba, slot_idx);
        spin_unlock_irqrestore(&hisi_hba->lock, flags);
-       spin_unlock_irqrestore(&dq->lock, flags_dq);
 err_out:
        dev_err(dev, "internal abort task prep: failed[%d]!\n", rc);