From bb52d82f45df3a2661d88befba7c79a7db8be496 Mon Sep 17 00:00:00 2001 From: Boaz Harrosh Date: Thu, 13 Dec 2007 16:14:27 -0800 Subject: [PATCH] [SCSI] tgt: use scsi_init_io instead of scsi_alloc_sgtable If we export scsi_init_io()/scsi_release_buffers() instead of scsi_{alloc,free}_sgtable() from scsi_lib than tgt code is much more insulated from scsi_lib changes. As a bonus it will also gain bidi capability when it comes. [jejb: rebase on to sg_table and fix up rejections] Signed-off-by: Boaz Harrosh Acked-by: FUJITA Tomonori Signed-off-by: Andrew Morton Signed-off-by: James Bottomley --- drivers/scsi/scsi_lib.c | 20 +++++++++----------- drivers/scsi/scsi_tgt_lib.c | 28 +++++----------------------- include/scsi/scsi_cmnd.h | 4 ++-- 3 files changed, 16 insertions(+), 36 deletions(-) diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c index 7c4c889c522..69fd62183ba 100644 --- a/drivers/scsi/scsi_lib.c +++ b/drivers/scsi/scsi_lib.c @@ -746,7 +746,7 @@ static struct scatterlist *scsi_sg_alloc(unsigned int nents, gfp_t gfp_mask) return mempool_alloc(sgp->pool, gfp_mask); } -int scsi_alloc_sgtable(struct scsi_cmnd *cmd, gfp_t gfp_mask) +static int scsi_alloc_sgtable(struct scsi_cmnd *cmd, gfp_t gfp_mask) { int ret; @@ -762,15 +762,11 @@ int scsi_alloc_sgtable(struct scsi_cmnd *cmd, gfp_t gfp_mask) return ret; } -EXPORT_SYMBOL(scsi_alloc_sgtable); - -void scsi_free_sgtable(struct scsi_cmnd *cmd) +static void scsi_free_sgtable(struct scsi_cmnd *cmd) { __sg_free_table(&cmd->sg_table, SCSI_MAX_SG_SEGMENTS, scsi_sg_free); } -EXPORT_SYMBOL(scsi_free_sgtable); - /* * Function: scsi_release_buffers() * @@ -788,7 +784,7 @@ EXPORT_SYMBOL(scsi_free_sgtable); * the scatter-gather table, and potentially any bounce * buffers. */ -static void scsi_release_buffers(struct scsi_cmnd *cmd) +void scsi_release_buffers(struct scsi_cmnd *cmd) { if (cmd->use_sg) scsi_free_sgtable(cmd); @@ -800,6 +796,7 @@ static void scsi_release_buffers(struct scsi_cmnd *cmd) cmd->request_buffer = NULL; cmd->request_bufflen = 0; } +EXPORT_SYMBOL(scsi_release_buffers); /* * Function: scsi_io_completion() @@ -1001,7 +998,7 @@ void scsi_io_completion(struct scsi_cmnd *cmd, unsigned int good_bytes) * Returns: 0 on success * BLKPREP_DEFER if the failure is retryable */ -static int scsi_init_io(struct scsi_cmnd *cmd) +int scsi_init_io(struct scsi_cmnd *cmd, gfp_t gfp_mask) { struct request *req = cmd->request; int count; @@ -1016,7 +1013,7 @@ static int scsi_init_io(struct scsi_cmnd *cmd) /* * If sg table allocation fails, requeue request later. */ - if (unlikely(scsi_alloc_sgtable(cmd, GFP_ATOMIC))) { + if (unlikely(scsi_alloc_sgtable(cmd, gfp_mask))) { scsi_unprep_request(req); return BLKPREP_DEFER; } @@ -1036,6 +1033,7 @@ static int scsi_init_io(struct scsi_cmnd *cmd) cmd->use_sg = count; return BLKPREP_OK; } +EXPORT_SYMBOL(scsi_init_io); static struct scsi_cmnd *scsi_get_cmd_from_req(struct scsi_device *sdev, struct request *req) @@ -1081,7 +1079,7 @@ int scsi_setup_blk_pc_cmnd(struct scsi_device *sdev, struct request *req) BUG_ON(!req->nr_phys_segments); - ret = scsi_init_io(cmd); + ret = scsi_init_io(cmd, GFP_ATOMIC); if (unlikely(ret)) return ret; } else { @@ -1132,7 +1130,7 @@ int scsi_setup_fs_cmnd(struct scsi_device *sdev, struct request *req) if (unlikely(!cmd)) return BLKPREP_DEFER; - return scsi_init_io(cmd); + return scsi_init_io(cmd, GFP_ATOMIC); } EXPORT_SYMBOL(scsi_setup_fs_cmnd); diff --git a/drivers/scsi/scsi_tgt_lib.c b/drivers/scsi/scsi_tgt_lib.c index 01e03f3f6ff..91630baea53 100644 --- a/drivers/scsi/scsi_tgt_lib.c +++ b/drivers/scsi/scsi_tgt_lib.c @@ -331,8 +331,7 @@ static void scsi_tgt_cmd_done(struct scsi_cmnd *cmd) scsi_tgt_uspace_send_status(cmd, tcmd->itn_id, tcmd->tag); - if (scsi_sglist(cmd)) - scsi_free_sgtable(cmd); + scsi_release_buffers(cmd); queue_work(scsi_tgtd, &tcmd->work); } @@ -353,25 +352,6 @@ static int scsi_tgt_transfer_response(struct scsi_cmnd *cmd) return 0; } -static int scsi_tgt_init_cmd(struct scsi_cmnd *cmd, gfp_t gfp_mask) -{ - struct request *rq = cmd->request; - int count; - - cmd->use_sg = rq->nr_phys_segments; - if (scsi_alloc_sgtable(cmd, gfp_mask)) - return -ENOMEM; - - cmd->request_bufflen = rq->data_len; - - dprintk("cmd %p cnt %d %lu\n", cmd, scsi_sg_count(cmd), - rq_data_dir(rq)); - count = blk_rq_map_sg(rq->q, rq, scsi_sglist(cmd)); - BUG_ON(count > cmd->use_sg); - cmd->use_sg = count; - return 0; -} - /* TODO: test this crap and replace bio_map_user with new interface maybe */ static int scsi_map_user_pages(struct scsi_tgt_cmd *tcmd, struct scsi_cmnd *cmd, unsigned long uaddr, unsigned int len, int rw) @@ -397,9 +377,11 @@ static int scsi_map_user_pages(struct scsi_tgt_cmd *tcmd, struct scsi_cmnd *cmd, } tcmd->bio = rq->bio; - err = scsi_tgt_init_cmd(cmd, GFP_KERNEL); - if (err) + err = scsi_init_io(cmd, GFP_KERNEL); + if (err) { + scsi_release_buffers(cmd); goto unmap_rq; + } return 0; diff --git a/include/scsi/scsi_cmnd.h b/include/scsi/scsi_cmnd.h index a457fca66f6..09d44f91dbd 100644 --- a/include/scsi/scsi_cmnd.h +++ b/include/scsi/scsi_cmnd.h @@ -127,8 +127,8 @@ extern void *scsi_kmap_atomic_sg(struct scatterlist *sg, int sg_count, size_t *offset, size_t *len); extern void scsi_kunmap_atomic_sg(void *virt); -extern int scsi_alloc_sgtable(struct scsi_cmnd *, gfp_t); -extern void scsi_free_sgtable(struct scsi_cmnd *); +extern int scsi_init_io(struct scsi_cmnd *cmd, gfp_t gfp_mask); +extern void scsi_release_buffers(struct scsi_cmnd *cmd); extern int scsi_dma_map(struct scsi_cmnd *cmd); extern void scsi_dma_unmap(struct scsi_cmnd *cmd);