Simply transport_generic_new_cmd to only allocate a single task. For normal
unidirection commands nothing changes except that the code is a lot simpler
now. Any BIDI support that used to work will stop now for the next few
patches at least.
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
drivers/target/target_core_transport.c | 157 +++++++--------------------------
1 file changed, 37 insertions(+), 120 deletions(-)
Index: lio-core/drivers/target/target_core_transport.c
===================================================================
--- lio-core.orig/drivers/target/target_core_transport.c 2012-04-24 06:08:46.020369993 +0200
+++ lio-core/drivers/target/target_core_transport.c 2012-04-24 06:08:47.636370035 +0200
@@ -1477,29 +1477,6 @@ static inline void transport_generic_pre
}
}
-static struct se_task *
-transport_generic_get_task(struct se_cmd *cmd,
- enum dma_data_direction data_direction)
-{
- struct se_task *task;
- struct se_device *dev = cmd->se_dev;
-
- task = dev->transport->alloc_task(cmd->t_task_cdb);
- if (!task) {
- pr_err("Unable to allocate struct se_task\n");
- return NULL;
- }
-
- INIT_LIST_HEAD(&task->t_list);
- INIT_LIST_HEAD(&task->t_execute_list);
- INIT_LIST_HEAD(&task->t_state_list);
- init_completion(&task->task_stop_comp);
- task->task_se_cmd = cmd;
- task->task_data_direction = data_direction;
-
- return task;
-}
-
static int transport_generic_cmd_sequencer(struct se_cmd *, unsigned char *);
/*
@@ -3704,68 +3681,6 @@ out:
}
/*
- * Break up cmd into chunks transport can handle
- */
-static int
-transport_allocate_data_tasks(struct se_cmd *cmd,
- enum dma_data_direction data_direction,
- struct scatterlist *cmd_sg, unsigned int sgl_nents)
-{
- struct se_device *dev = cmd->se_dev;
- struct se_dev_attrib *attr = &dev->se_sub_dev->se_dev_attrib;
- sector_t sectors;
- struct se_task *task;
- unsigned long flags;
-
- if (transport_cmd_get_valid_sectors(cmd) < 0)
- return -EINVAL;
-
- sectors = DIV_ROUND_UP(cmd->data_length, attr->block_size);
-
- BUG_ON(cmd->data_length % attr->block_size);
- BUG_ON(sectors > attr->max_sectors);
-
- task = transport_generic_get_task(cmd, data_direction);
- if (!task)
- return -ENOMEM;
-
- task->task_sg = cmd_sg;
- task->task_sg_nents = sgl_nents;
-
- spin_lock_irqsave(&cmd->t_state_lock, flags);
- list_add_tail(&task->t_list, &cmd->t_task_list);
- spin_unlock_irqrestore(&cmd->t_state_lock, flags);
-
- return 1;
-}
-
-static int
-transport_allocate_control_task(struct se_cmd *cmd)
-{
- struct se_task *task;
- unsigned long flags;
-
- /* Workaround for handling zero-length control CDBs */
- if ((cmd->se_cmd_flags & SCF_SCSI_CONTROL_SG_IO_CDB) &&
- !cmd->data_length)
- return 0;
-
- task = transport_generic_get_task(cmd, cmd->data_direction);
- if (!task)
- return -ENOMEM;
-
- task->task_sg = cmd->t_data_sg;
- task->task_sg_nents = cmd->t_data_nents;
-
- spin_lock_irqsave(&cmd->t_state_lock, flags);
- list_add_tail(&task->t_list, &cmd->t_task_list);
- spin_unlock_irqrestore(&cmd->t_state_lock, flags);
-
- /* Success! Return number of tasks allocated */
- return 1;
-}
-
-/*
* Allocate any required resources to execute the command. For writes we
* might not have the payload yet, so notify the fabric via a call to
* ->write_pending instead. Otherwise place it on the execution queue.
@@ -3773,8 +3688,8 @@ transport_allocate_control_task(struct s
int transport_generic_new_cmd(struct se_cmd *cmd)
{
struct se_device *dev = cmd->se_dev;
- int task_cdbs, task_cdbs_bidi = 0;
- int set_counts = 1;
+ struct se_task *task;
+ unsigned long flags;
int ret = 0;
/*
@@ -3789,35 +3704,9 @@ int transport_generic_new_cmd(struct se_
goto out_fail;
}
- /*
- * For BIDI command set up the read tasks first.
- */
- if (cmd->t_bidi_data_sg &&
- dev->transport->transport_type != TRANSPORT_PLUGIN_PHBA_PDEV) {
- BUG_ON(!(cmd->se_cmd_flags & SCF_SCSI_DATA_SG_IO_CDB));
-
- task_cdbs_bidi = transport_allocate_data_tasks(cmd,
- DMA_FROM_DEVICE, cmd->t_bidi_data_sg,
- cmd->t_bidi_data_nents);
- if (task_cdbs_bidi <= 0)
- goto out_fail;
-
- atomic_inc(&cmd->t_fe_count);
- atomic_inc(&cmd->t_se_count);
- set_counts = 0;
- }
-
- if (cmd->se_cmd_flags & SCF_SCSI_DATA_SG_IO_CDB) {
- task_cdbs = transport_allocate_data_tasks(cmd,
- cmd->data_direction, cmd->t_data_sg,
- cmd->t_data_nents);
- } else {
- task_cdbs = transport_allocate_control_task(cmd);
- }
-
- if (task_cdbs < 0)
- goto out_fail;
- else if (!task_cdbs && (cmd->se_cmd_flags & SCF_SCSI_DATA_SG_IO_CDB)) {
+ /* Workaround for handling zero-length control CDBs */
+ if ((cmd->se_cmd_flags & SCF_SCSI_CONTROL_SG_IO_CDB) &&
+ !cmd->data_length) {
spin_lock_irq(&cmd->t_state_lock);
cmd->t_state = TRANSPORT_COMPLETE;
cmd->transport_state |= CMD_T_ACTIVE;
@@ -3835,12 +3724,40 @@ int transport_generic_new_cmd(struct se_
return 0;
}
- if (set_counts) {
- atomic_inc(&cmd->t_fe_count);
- atomic_inc(&cmd->t_se_count);
+ if (cmd->se_cmd_flags & SCF_SCSI_DATA_SG_IO_CDB) {
+ struct se_dev_attrib *attr = &dev->se_sub_dev->se_dev_attrib;
+
+ if (transport_cmd_get_valid_sectors(cmd) < 0)
+ return -EINVAL;
+
+ BUG_ON(cmd->data_length % attr->block_size);
+ BUG_ON(DIV_ROUND_UP(cmd->data_length, attr->block_size) >
+ attr->max_sectors);
+ }
+
+ task = dev->transport->alloc_task(cmd->t_task_cdb);
+ if (!task) {
+ pr_err("Unable to allocate struct se_task\n");
+ goto out_fail;
}
- cmd->t_task_list_num = (task_cdbs + task_cdbs_bidi);
+ INIT_LIST_HEAD(&task->t_list);
+ INIT_LIST_HEAD(&task->t_execute_list);
+ INIT_LIST_HEAD(&task->t_state_list);
+ init_completion(&task->task_stop_comp);
+ task->task_se_cmd = cmd;
+ task->task_data_direction = cmd->data_direction;
+ task->task_sg = cmd->t_data_sg;
+ task->task_sg_nents = cmd->t_data_nents;
+
+ spin_lock_irqsave(&cmd->t_state_lock, flags);
+ list_add_tail(&task->t_list, &cmd->t_task_list);
+ spin_unlock_irqrestore(&cmd->t_state_lock, flags);
+
+ atomic_inc(&cmd->t_fe_count);
+ atomic_inc(&cmd->t_se_count);
+
+ cmd->t_task_list_num = 1;
atomic_set(&cmd->t_task_cdbs_left, cmd->t_task_list_num);
atomic_set(&cmd->t_task_cdbs_ex_left, cmd->t_task_list_num);
--
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