From dd9cf04611c566f980638ec0c592c38ea5d463ce Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 19 Jul 2016 11:31:52 +0200 Subject: [PATCH] target: stop using blk_make_request Using blk_rq_append_bio allows to append the bios to the request directly instead of having to build up a list first, and also allows to have a single code path for requests with or without data attached to them. Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe --- drivers/target/target_core_pscsi.c | 87 ++++++++++++------------------ 1 file changed, 34 insertions(+), 53 deletions(-) diff --git a/drivers/target/target_core_pscsi.c b/drivers/target/target_core_pscsi.c index 81564c87f24b..9125d9358dea 100644 --- a/drivers/target/target_core_pscsi.c +++ b/drivers/target/target_core_pscsi.c @@ -876,19 +876,19 @@ static inline struct bio *pscsi_get_bio(int nr_vecs) static sense_reason_t pscsi_map_sg(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents, - enum dma_data_direction data_direction, struct bio **hbio) + struct request *req) { struct pscsi_dev_virt *pdv = PSCSI_DEV(cmd->se_dev); - struct bio *bio = NULL, *tbio = NULL; + struct bio *bio = NULL; struct page *page; struct scatterlist *sg; u32 data_len = cmd->data_length, i, len, bytes, off; int nr_pages = (cmd->data_length + sgl[0].offset + PAGE_SIZE - 1) >> PAGE_SHIFT; int nr_vecs = 0, rc; - int rw = (data_direction == DMA_TO_DEVICE); + int rw = (cmd->data_direction == DMA_TO_DEVICE); - *hbio = NULL; + BUG_ON(!cmd->data_length); pr_debug("PSCSI: nr_pages: %d\n", nr_pages); @@ -927,16 +927,6 @@ pscsi_map_sg(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents, pr_debug("PSCSI: Allocated bio: %p," " dir: %s nr_vecs: %d\n", bio, (rw) ? "rw" : "r", nr_vecs); - /* - * Set *hbio pointer to handle the case: - * nr_pages > BIO_MAX_PAGES, where additional - * bios need to be added to complete a given - * command. - */ - if (!*hbio) - *hbio = tbio = bio; - else - tbio = tbio->bi_next = bio; } pr_debug("PSCSI: Calling bio_add_pc_page() i: %d" @@ -955,11 +945,16 @@ pscsi_map_sg(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents, pr_debug("PSCSI: Reached bio->bi_vcnt max:" " %d i: %d bio: %p, allocating another" " bio\n", bio->bi_vcnt, i, bio); + + rc = blk_rq_append_bio(req, bio); + if (rc) { + pr_err("pSCSI: failed to append bio\n"); + goto fail; + } + /* * Clear the pointer so that another bio will - * be allocated with pscsi_get_bio() above, the - * current bio has already been set *tbio and - * bio->bi_next. + * be allocated with pscsi_get_bio() above. */ bio = NULL; } @@ -968,13 +963,16 @@ pscsi_map_sg(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents, } } + if (bio) { + rc = blk_rq_append_bio(req, bio); + if (rc) { + pr_err("pSCSI: failed to append bio\n"); + goto fail; + } + } + return 0; fail: - while (*hbio) { - bio = *hbio; - *hbio = (*hbio)->bi_next; - bio_endio(bio); - } return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; } @@ -992,11 +990,9 @@ pscsi_execute_cmd(struct se_cmd *cmd) { struct scatterlist *sgl = cmd->t_data_sg; u32 sgl_nents = cmd->t_data_nents; - enum dma_data_direction data_direction = cmd->data_direction; struct pscsi_dev_virt *pdv = PSCSI_DEV(cmd->se_dev); struct pscsi_plugin_task *pt; struct request *req; - struct bio *hbio; sense_reason_t ret; /* @@ -1012,31 +1008,21 @@ pscsi_execute_cmd(struct se_cmd *cmd) memcpy(pt->pscsi_cdb, cmd->t_task_cdb, scsi_command_size(cmd->t_task_cdb)); - if (!sgl) { - req = blk_get_request(pdv->pdv_sd->request_queue, - (data_direction == DMA_TO_DEVICE), - GFP_KERNEL); - if (IS_ERR(req)) { - pr_err("PSCSI: blk_get_request() failed\n"); - ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; - goto fail; - } + req = blk_get_request(pdv->pdv_sd->request_queue, + (cmd->data_direction == DMA_TO_DEVICE), + GFP_KERNEL); + if (IS_ERR(req)) { + pr_err("PSCSI: blk_get_request() failed\n"); + ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; + goto fail; + } - blk_rq_set_block_pc(req); - } else { - BUG_ON(!cmd->data_length); + blk_rq_set_block_pc(req); - ret = pscsi_map_sg(cmd, sgl, sgl_nents, data_direction, &hbio); + if (sgl) { + ret = pscsi_map_sg(cmd, sgl, sgl_nents, req); if (ret) - goto fail; - - req = blk_make_request(pdv->pdv_sd->request_queue, hbio, - GFP_KERNEL); - if (IS_ERR(req)) { - pr_err("pSCSI: blk_make_request() failed\n"); - ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; - goto fail_free_bio; - } + goto fail_put_request; } req->end_io = pscsi_req_done; @@ -1057,13 +1043,8 @@ pscsi_execute_cmd(struct se_cmd *cmd) return 0; -fail_free_bio: - while (hbio) { - struct bio *bio = hbio; - hbio = hbio->bi_next; - bio_endio(bio); - } - ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; +fail_put_request: + blk_put_request(req); fail: kfree(pt); return ret; -- 2.39.2