[SCSI] remove scsi_req_map_sg

No one uses scsi_execute_async with data transfer now. We can remove
scsi_req_map_sg.

Only scsi_eh_lock_door uses scsi_execute_async. scsi_eh_lock_door
doesn't handle sense and the callback. So we can remove
scsi_io_context too.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

2 files changed, 25 insertions, 212 deletions

diff --git a/drivers/scsi/scsi_error.c b/drivers/scsi/scsi_error.c
index ad6a1370761..0c2c73be197 100644
--- a/drivers/scsi/scsi_error.c
+++ b/drivers/scsi/scsi_error.c
@@ -1441,6 +1441,11 @@ int scsi_decide_disposition(struct scsi_cmnd *scmd)
         }
 }
 
+static void eh_lock_door_done(struct request *req, int uptodate)
+{
+        __blk_put_request(req->q, req);
+}
+
 /**
  * scsi_eh_lock_door - Prevent medium removal for the specified device
  * @sdev:       SCSI device to prevent medium removal
@@ -1463,19 +1468,28 @@ int scsi_decide_disposition(struct scsi_cmnd *scmd)
  */
 static void scsi_eh_lock_door(struct scsi_device *sdev)
 {
-        unsigned char cmnd[MAX_COMMAND_SIZE];
+        struct request *req;
 
-        cmnd[0] = ALLOW_MEDIUM_REMOVAL;
-        cmnd[1] = 0;
-        cmnd[2] = 0;
-        cmnd[3] = 0;
-        cmnd[4] = SCSI_REMOVAL_PREVENT;
-        cmnd[5] = 0;
+        req = blk_get_request(sdev->request_queue, READ, GFP_KERNEL);
+        if (!req)
+                return;
 
-        scsi_execute_async(sdev, cmnd, 6, DMA_NONE, NULL, 0, 0, 10 * HZ,
-                           5, NULL, NULL, GFP_KERNEL);
-}
+        req->cmd[0] = ALLOW_MEDIUM_REMOVAL;
+        req->cmd[1] = 0;
+        req->cmd[2] = 0;
+        req->cmd[3] = 0;
+        req->cmd[4] = SCSI_REMOVAL_PREVENT;
+        req->cmd[5] = 0;
 
+        req->cmd_len = COMMAND_SIZE(req->cmd[0]);
+
+        req->cmd_type = REQ_TYPE_BLOCK_PC;
+        req->cmd_flags |= REQ_QUIET;
+        req->timeout = 10 * HZ;
+        req->retries = 5;
+
+        blk_execute_rq_nowait(req->q, NULL, req, 1, eh_lock_door_done);
+}
 
 /**
  * scsi_restart_operations - restart io operations to the specified host.
diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index b82ffd90632..4b13e36d3aa 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -277,196 +277,6 @@ int scsi_execute_req(struct scsi_device *sdev, const unsigned char *cmd,
 }
 EXPORT_SYMBOL(scsi_execute_req);
 
-struct scsi_io_context {
-        void *data;
-        void (*done)(void *data, char *sense, int result, int resid);
-        char sense[SCSI_SENSE_BUFFERSIZE];
-};
-
-static struct kmem_cache *scsi_io_context_cache;
-
-static void scsi_end_async(struct request *req, int uptodate)
-{
-        struct scsi_io_context *sioc = req->end_io_data;
-
-        if (sioc->done)
-                sioc->done(sioc->data, sioc->sense, req->errors, req->data_len);
-
-        kmem_cache_free(scsi_io_context_cache, sioc);
-        __blk_put_request(req->q, req);
-}
-
-static int scsi_merge_bio(struct request *rq, struct bio *bio)
-{
-        struct request_queue *q = rq->q;
-
-        bio->bi_flags &= ~(1 << BIO_SEG_VALID);
-        if (rq_data_dir(rq) == WRITE)
-                bio->bi_rw |= (1 << BIO_RW);
-        blk_queue_bounce(q, &bio);
-
-        return blk_rq_append_bio(q, rq, bio);
-}
-
-static void scsi_bi_endio(struct bio *bio, int error)
-{
-        bio_put(bio);
-}
-
-/**
- * scsi_req_map_sg - map a scatterlist into a request
- * @rq:         request to fill
- * @sgl:        scatterlist
- * @nsegs:      number of elements
- * @bufflen:    len of buffer
- * @gfp:        memory allocation flags
- *
- * scsi_req_map_sg maps a scatterlist into a request so that the
- * request can be sent to the block layer. We do not trust the scatterlist
- * sent to use, as some ULDs use that struct to only organize the pages.
- */
-static int scsi_req_map_sg(struct request *rq, struct scatterlist *sgl,
-                           int nsegs, unsigned bufflen, gfp_t gfp)
-{
-        struct request_queue *q = rq->q;
-        int nr_pages = (bufflen + sgl[0].offset + PAGE_SIZE - 1) >> PAGE_SHIFT;
-        unsigned int data_len = bufflen, len, bytes, off;
-        struct scatterlist *sg;
-        struct page *page;
-        struct bio *bio = NULL;
-        int i, err, nr_vecs = 0;
-
-        for_each_sg(sgl, sg, nsegs, i) {
-                page = sg_page(sg);
-                off = sg->offset;
-                len = sg->length;
-
-                while (len > 0 && data_len > 0) {
-                        /*
-                         * sg sends a scatterlist that is larger than
-                         * the data_len it wants transferred for certain
-                         * IO sizes
-                         */
-                        bytes = min_t(unsigned int, len, PAGE_SIZE - off);
-                        bytes = min(bytes, data_len);
-
-                        if (!bio) {
-                                nr_vecs = min_t(int, BIO_MAX_PAGES, nr_pages);
-                                nr_pages -= nr_vecs;
-
-                                bio = bio_alloc(gfp, nr_vecs);
-                                if (!bio) {
-                                        err = -ENOMEM;
-                                        goto free_bios;
-                                }
-                                bio->bi_end_io = scsi_bi_endio;
-                        }
-
-                        if (bio_add_pc_page(q, bio, page, bytes, off) !=
-                            bytes) {
-                                bio_put(bio);
-                                err = -EINVAL;
-                                goto free_bios;
-                        }
-
-                        if (bio->bi_vcnt >= nr_vecs) {
-                                err = scsi_merge_bio(rq, bio);
-                                if (err) {
-                                        bio_endio(bio, 0);
-                                        goto free_bios;
-                                }
-                                bio = NULL;
-                        }
-
-                        page++;
-                        len -= bytes;
-                        data_len -=bytes;
-                        off = 0;
-                }
-        }
-
-        rq->buffer = rq->data = NULL;
-        rq->data_len = bufflen;
-        return 0;
-
-free_bios:
-        while ((bio = rq->bio) != NULL) {
-                rq->bio = bio->bi_next;
-                /*
-                 * call endio instead of bio_put incase it was bounced
-                 */
-                bio_endio(bio, 0);
-        }
-
-        return err;
-}
-
-/**
- * scsi_execute_async - insert request
- * @sdev:       scsi device
- * @cmd:        scsi command
- * @cmd_len:    length of scsi cdb
- * @data_direction: DMA_TO_DEVICE, DMA_FROM_DEVICE, or DMA_NONE
- * @buffer:     data buffer (this can be a kernel buffer or scatterlist)
- * @bufflen:    len of buffer
- * @use_sg:     if buffer is a scatterlist this is the number of elements
- * @timeout:    request timeout in seconds
- * @retries:    number of times to retry request
- * @privdata:   data passed to done()
- * @done:       callback function when done
- * @gfp:        memory allocation flags
- */
-int scsi_execute_async(struct scsi_device *sdev, const unsigned char *cmd,
-                       int cmd_len, int data_direction, void *buffer, unsigned bufflen,
-                       int use_sg, int timeout, int retries, void *privdata,
-                       void (*done)(void *, char *, int, int), gfp_t gfp)
-{
-        struct request *req;
-        struct scsi_io_context *sioc;
-        int err = 0;
-        int write = (data_direction == DMA_TO_DEVICE);
-
-        sioc = kmem_cache_zalloc(scsi_io_context_cache, gfp);
-        if (!sioc)
-                return DRIVER_ERROR << 24;
-
-        req = blk_get_request(sdev->request_queue, write, gfp);
-        if (!req)
-                goto free_sense;
-        req->cmd_type = REQ_TYPE_BLOCK_PC;
-        req->cmd_flags |= REQ_QUIET;
-
-        if (use_sg)
-                err = scsi_req_map_sg(req, buffer, use_sg, bufflen, gfp);
-        else if (bufflen)
-                err = blk_rq_map_kern(req->q, req, buffer, bufflen, gfp);
-
-        if (err)
-                goto free_req;
-
-        req->cmd_len = cmd_len;
-        memset(req->cmd, 0, BLK_MAX_CDB); /* ATAPI hates garbage after CDB */
-        memcpy(req->cmd, cmd, req->cmd_len);
-        req->sense = sioc->sense;
-        req->sense_len = 0;
-        req->timeout = timeout;
-        req->retries = retries;
-        req->end_io_data = sioc;
-
-        sioc->data = privdata;
-        sioc->done = done;
-
-        blk_execute_rq_nowait(req->q, NULL, req, 1, scsi_end_async);
-        return 0;
-
-free_req:
-        blk_put_request(req);
-free_sense:
-        kmem_cache_free(scsi_io_context_cache, sioc);
-        return DRIVER_ERROR << 24;
-}
-EXPORT_SYMBOL_GPL(scsi_execute_async);
-
 /*
  * Function:    scsi_init_cmd_errh()
  *
@@ -1920,20 +1730,12 @@ int __init scsi_init_queue(void)
 {
         int i;
 
-        scsi_io_context_cache = kmem_cache_create("scsi_io_context",
-                                        sizeof(struct scsi_io_context),
-                                        0, 0, NULL);
-        if (!scsi_io_context_cache) {
-                printk(KERN_ERR "SCSI: can't init scsi io context cache\n");
-                return -ENOMEM;
-        }
-
         scsi_sdb_cache = kmem_cache_create("scsi_data_buffer",
                                            sizeof(struct scsi_data_buffer),
                                            0, 0, NULL);
         if (!scsi_sdb_cache) {
                 printk(KERN_ERR "SCSI: can't init scsi sdb cache\n");
-                goto cleanup_io_context;
+                return -ENOMEM;
         }
 
         for (i = 0; i < SG_MEMPOOL_NR; i++) {
@@ -1968,8 +1770,6 @@ cleanup_sdb:
                         kmem_cache_destroy(sgp->slab);
         }
         kmem_cache_destroy(scsi_sdb_cache);
-cleanup_io_context:
-        kmem_cache_destroy(scsi_io_context_cache);
 
         return -ENOMEM;
 }
@@ -1978,7 +1778,6 @@ void scsi_exit_queue(void)
 {
         int i;
 
-        kmem_cache_destroy(scsi_io_context_cache);
         kmem_cache_destroy(scsi_sdb_cache);
 
         for (i = 0; i < SG_MEMPOOL_NR; i++) {