From: Nicholas Bellinger <nab@xxxxxxxxxxxxxxx> This patch adds a transport_handle_cdb_direct() optimization for mapping and queueing tasks directly from within fabric processing context by calling the newly exported transport_generic_new_cmd(). This currently expects to be called from process context only, and will fail if called within interrupt context. This patch also leaves transport_generic_handle_cdb() unmodified for the moment to function as expected with existing tcm_fc and ib_srpt fabrics, and will be removed once these have been converted and tested with v4.1 code using transport_handle_cdb_direct(). Based on Andy's original patch here: [PATCH 39/42] target: Call transport_new_cmd instead of adding to cmd queue Signed-off-by: Nicholas Bellinger <nab@xxxxxxxxxxxxxxx> --- drivers/target/target_core_transport.c | 24 ++++++++++++++++++++++++ include/target/target_core_transport.h | 1 + 2 files changed, 25 insertions(+), 0 deletions(-) diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c index d42a98e..1ae6eb7 100644 --- a/drivers/target/target_core_transport.c +++ b/drivers/target/target_core_transport.c @@ -1842,12 +1842,36 @@ int transport_generic_handle_cdb( printk(KERN_ERR "cmd->se_lun is NULL\n"); return -EINVAL; } + transport_add_cmd_to_queue(cmd, TRANSPORT_NEW_CMD); return 0; } EXPORT_SYMBOL(transport_generic_handle_cdb); /* + * Used by fabric module frontends to queue tasks directly. + * Many only be used from process context only + */ +int transport_handle_cdb_direct( + struct se_cmd *cmd) +{ + if (!cmd->se_lun) { + dump_stack(); + printk(KERN_ERR "cmd->se_lun is NULL\n"); + return -EINVAL; + } + if (in_interrupt()) { + dump_stack(); + printk(KERN_ERR "transport_generic_handle_cdb cannot be called" + " from interrupt context\n"); + return -EINVAL; + } + + return transport_generic_new_cmd(cmd); +} +EXPORT_SYMBOL(transport_handle_cdb_direct); + +/* * Used by fabric module frontends defining a TFO->new_cmd_map() caller * to queue up a newly setup se_cmd w/ TRANSPORT_NEW_CMD_MAP in order to * complete setup in TCM process context w/ TFO->new_cmd_map(). diff --git a/include/target/target_core_transport.h b/include/target/target_core_transport.h index 604e669..2aae764 100644 --- a/include/target/target_core_transport.h +++ b/include/target/target_core_transport.h @@ -166,6 +166,7 @@ extern void transport_init_se_cmd(struct se_cmd *, extern void transport_free_se_cmd(struct se_cmd *); extern int transport_generic_allocate_tasks(struct se_cmd *, unsigned char *); extern int transport_generic_handle_cdb(struct se_cmd *); +extern int transport_handle_cdb_direct(struct se_cmd *); extern int transport_generic_handle_cdb_map(struct se_cmd *); extern int transport_generic_handle_data(struct se_cmd *); extern void transport_new_cmd_failure(struct se_cmd *); -- 1.7.6 -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html