diff options
author | Roland Dreier <roland@purestorage.com> | 2012-03-30 18:29:15 (GMT) |
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committer | Nicholas Bellinger <nab@linux-iscsi.org> | 2012-04-15 00:40:32 (GMT) |
commit | 957525a2424aad367d6e0efb64e440b2b37fa5cd (patch) | |
tree | dc56eaa7a6e60ad674059d110e6d4145adb55efd /drivers/target/target_core_transport.c | |
parent | 6f9e7f01b69bc2d6021e4ab827e1fd78c82cbc52 (diff) | |
download | linux-fsl-qoriq-957525a2424aad367d6e0efb64e440b2b37fa5cd.tar.xz |
target: Remove transport_do_task_sg_chain() and associated detritus
Now that all fabrics are converted over to using se_cmd->t_data_sg
directly, we can drop the task sg chaining support. With the modern
memory allocation in target core, task sg chaining is needless
overhead -- we would split up the main cmd sglist into pieces, and
then splice those pieces back together instead of just using the
original list directly.
Signed-off-by: Roland Dreier <roland@purestorage.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Diffstat (limited to 'drivers/target/target_core_transport.c')
-rw-r--r-- | drivers/target/target_core_transport.c | 70 |
1 files changed, 0 insertions, 70 deletions
diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c index db05c75..9fdc708 100644 --- a/drivers/target/target_core_transport.c +++ b/drivers/target/target_core_transport.c @@ -3699,76 +3699,6 @@ static inline sector_t transport_limit_task_sectors( return sectors; } - -/* - * This function can be used by HW target mode drivers to create a linked - * scatterlist from all contiguously allocated struct se_task->task_sg[]. - * This is intended to be called during the completion path by TCM Core - * when struct target_core_fabric_ops->check_task_sg_chaining is enabled. - */ -void transport_do_task_sg_chain(struct se_cmd *cmd) -{ - struct scatterlist *sg_first = NULL; - struct scatterlist *sg_prev = NULL; - int sg_prev_nents = 0; - struct scatterlist *sg; - struct se_task *task; - u32 chained_nents = 0; - int i; - - BUG_ON(!cmd->se_tfo->task_sg_chaining); - - /* - * Walk the struct se_task list and setup scatterlist chains - * for each contiguously allocated struct se_task->task_sg[]. - */ - list_for_each_entry(task, &cmd->t_task_list, t_list) { - if (!task->task_sg) - continue; - - if (!sg_first) { - sg_first = task->task_sg; - chained_nents = task->task_sg_nents; - } else { - sg_chain(sg_prev, sg_prev_nents, task->task_sg); - chained_nents += task->task_sg_nents; - } - /* - * For the padded tasks, use the extra SGL vector allocated - * in transport_allocate_data_tasks() for the sg_prev_nents - * offset into sg_chain() above. - * - * We do not need the padding for the last task (or a single - * task), but in that case we will never use the sg_prev_nents - * value below which would be incorrect. - */ - sg_prev_nents = (task->task_sg_nents + 1); - sg_prev = task->task_sg; - } - /* - * Setup the starting pointer and total t_tasks_sg_linked_no including - * padding SGs for linking and to mark the end. - */ - cmd->t_tasks_sg_chained = sg_first; - cmd->t_tasks_sg_chained_no = chained_nents; - - pr_debug("Setup cmd: %p cmd->t_tasks_sg_chained: %p and" - " t_tasks_sg_chained_no: %u\n", cmd, cmd->t_tasks_sg_chained, - cmd->t_tasks_sg_chained_no); - - for_each_sg(cmd->t_tasks_sg_chained, sg, - cmd->t_tasks_sg_chained_no, i) { - - pr_debug("SG[%d]: %p page: %p length: %d offset: %d\n", - i, sg, sg_page(sg), sg->length, sg->offset); - if (sg_is_chain(sg)) - pr_debug("SG: %p sg_is_chain=1\n", sg); - if (sg_is_last(sg)) - pr_debug("SG: %p sg_is_last=1\n", sg); - } -} -EXPORT_SYMBOL(transport_do_task_sg_chain); - /* * Break up cmd into chunks transport can handle */ |