- Add bidi members to struct scsi_cmnd.
- Add API at the SCSI level for bidirectional commands.
- Implement support for BIDI requests in scsi_setup_blk_pc_cmnd() and
scsi_io_completion().
Signed-off-by: Benny Halevy <[email protected]>
Signed-off-by: Boaz Harrosh <[email protected]>
---
drivers/scsi/scsi_lib.c | 324 +++++++++++++++++++++++++++++++++++---------
include/scsi/scsi_cmnd.h | 55 +++++++-
include/scsi/scsi_device.h | 16 ++
3 files changed, 330 insertions(+), 65 deletions(-)
diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index 9c21025..92d3d44 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -246,27 +246,28 @@ static void scsi_end_async(struct reques
{
struct scsi_io_context *sioc = req->end_io_data;
- if (sioc->done)
- sioc->done(sioc->data, sioc->sense, req->errors, rq_uni(req)->data_len);
+ if (sioc->done) /* FIXME: API of done needs to change for bidi requests*/
+ sioc->done(sioc->data, sioc->sense, req->errors, req->uni.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)
+static int scsi_merge_bio(struct request *rq, struct bio *bio,
+ enum dma_data_direction dir)
{
struct request_queue *q = rq->q;
- struct request_io_part* req_io = rq_uni(rq);
+ struct request_io_part* req_io = rq_io(rq, dir);
bio->bi_flags &= ~(1 << BIO_SEG_VALID);
- if (rq_uni_write_dir(rq))
+ if (dir == DMA_TO_DEVICE)
bio->bi_rw |= (1 << BIO_RW);
else
bio->bi_rw &= ~(1 << BIO_RW);
blk_queue_bounce(q, &bio);
- if (!rq_uni(rq)->bio)
- blk_rq_bio_prep(q, rq, bio);
+ if (!req_io->bio)
+ blk_rq_bio_prep_bidi(q, rq, bio, dir);
else if (!ll_back_merge_fn(q, rq, bio))
return -EINVAL;
else {
@@ -299,7 +300,7 @@ static int scsi_bi_endio(struct bio *bio
* 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)
+ int nsegs, unsigned bufflen, gfp_t gfp, enum dma_data_direction dir)
{
struct request_queue *q = rq->q;
int nr_pages = (bufflen + sgl[0].offset + PAGE_SIZE - 1) >> PAGE_SHIFT;
@@ -337,7 +338,7 @@ static int scsi_req_map_sg(struct reques
}
if (bio->bi_vcnt >= nr_vecs) {
- err = scsi_merge_bio(rq, bio);
+ err = scsi_merge_bio(rq, bio ,dir);
if (err) {
bio_endio(bio, bio->bi_size, 0);
goto free_bios;
@@ -352,12 +353,12 @@ static int scsi_req_map_sg(struct reques
}
rq->buffer = rq->data = NULL;
- rq_uni(rq)->data_len = data_len;
+ rq_io(rq,dir)->data_len = data_len;
return 0;
free_bios:
- while ((bio = rq_uni(rq)->bio) != NULL) {
- rq_uni(rq)->bio = bio->bi_next;
+ while ((bio = rq_io(rq,dir)->bio) != NULL) {
+ rq_io(rq,dir)->bio = bio->bi_next;
/*
* call endio instead of bio_put incase it was bounced
*/
@@ -385,31 +386,89 @@ int scsi_execute_async(struct scsi_devic
int use_sg, int timeout, int retries, void *privdata,
void (*done)(void *, char *, int, int), gfp_t gfp)
{
+ struct scsi_cmnd_buff buff;
+
+ buff.use_sg = use_sg;
+ buff.buffer = buffer;
+ buff.bufflen = bufflen;
+
+ return scsi_execute_bidi_async(
+ sdev, (unsigned char *)cmd, cmd_len, data_direction,
+ &buff, NULL,
+ timeout, retries, privdata, done, gfp );
+}
+EXPORT_SYMBOL_GPL(scsi_execute_async);
+
+/**
+ * scsi_execute_bidi_async - insert bidi request, don't wait
+ * @sdev: scsi device
+ * @cmd: scsi command
+ * @cmd_len: length of scsi cdb
+ * @data_direction: data direction
+ * @bidi_write_buff.buffer: data buffer (this can be a kernel buffer or scatterlist)
+ * @bidi_write_buff.bufflen: len of buffer
+ * @bidi_write_buff.use_sg: if buffer is a scatterlist this is the number of elements
+ * @bidi_read_buff: same as above bidi_write_buff but for the bidi read part
+ * @timeout: request timeout in jiffies
+ * @retries: number of times to retry request
+ * @privdata: user data passed to done function
+ * @done: pointer to done function called at io completion.
+ * signature: void done(void *user_data, char *sence, int errors, int data_bytes_advanced)
+ * @gfp: gfp allocation flags
+ **/
+int scsi_execute_bidi_async(struct scsi_device *sdev,
+ unsigned char *cmd, int cmd_len, int data_direction,
+ struct scsi_cmnd_buff *buff, struct scsi_cmnd_buff *bidi_read_buff,
+ 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 is_bidi;
sioc = kmem_cache_alloc(scsi_io_context_cache, gfp);
if (!sioc)
return DRIVER_ERROR << 24;
memset(sioc, 0, sizeof(*sioc));
+ WARN_ON( (data_direction==DMA_NONE) && buff->bufflen);
+ WARN_ON( (data_direction!=DMA_NONE) && !buff->bufflen);
+ WARN_ON( (data_direction==DMA_BIDIRECTIONAL) && !bidi_read_buff);
req = blk_get_request(sdev->request_queue, data_direction, 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);
-
+ is_bidi = (data_direction == DMA_BIDIRECTIONAL);
+ if (buff->use_sg)
+ err = scsi_req_map_sg(
+ req, buff->buffer, buff->use_sg, buff->bufflen, gfp,
+ is_bidi ? DMA_TO_DEVICE : data_direction);
+ else if (buff->bufflen)
+ err = blk_rq_map_kern_bidi(
+ req->q, req, buff->buffer, buff->bufflen, gfp,
+ is_bidi ? DMA_TO_DEVICE : data_direction);
if (err)
goto free_req;
req->cmd_len = cmd_len;
memset(req->cmd, 0, BLK_MAX_CDB); /* ATAPI hates garbage after CDB */
+ if (is_bidi) {
+ if (bidi_read_buff->use_sg)
+ err = scsi_req_map_sg(
+ req, bidi_read_buff->buffer, bidi_read_buff->use_sg,
+ bidi_read_buff->bufflen, gfp, DMA_FROM_DEVICE);
+ else if (buff->bufflen)
+ err = blk_rq_map_kern_bidi(
+ req->q, req, bidi_read_buff->buffer,
+ bidi_read_buff->bufflen, gfp, DMA_FROM_DEVICE);
+ if (err) {
+ end_that_request_block(req ,0);/* free up the write part */
+ goto free_req;
+ }
+ }
+
memcpy(req->cmd, cmd, req->cmd_len);
req->sense = sioc->sense;
req->sense_len = 0;
@@ -429,7 +488,60 @@ free_sense:
kmem_cache_free(scsi_io_context_cache, sioc);
return DRIVER_ERROR << 24;
}
-EXPORT_SYMBOL_GPL(scsi_execute_async);
+EXPORT_SYMBOL_GPL(scsi_execute_bidi_async);
+
+struct scsi_execute_bidi_done_t {
+ struct completion *waiting;
+ char* sense;
+ int errors;
+} ;
+
+static void scsi_execute_bidi_done(void *user_data, char *sense, int errors, int data_len)
+{
+ struct scsi_execute_bidi_done_t *sebd = user_data;
+ sebd->errors = errors;
+ if (sebd->sense) {
+ memcpy(sebd->sense, sense, SCSI_SENSE_BUFFERSIZE);
+ }
+ complete(sebd->waiting);
+}
+
+/**
+ * scsi_execute_bidi - insert a bidi request
+ * @sdev: scsi device
+ * @cmd: scsi command
+ * @cmd_len: length of scsi cdb
+ * @data_direction: data direction
+ * @bidi_write_buff.buffer: data buffer (this can be a kernel buffer or scatterlist)
+ * @bidi_write_buff.bufflen: len of buffer
+ * @bidi_write_buff.use_sg: if buffer is a scatterlist this is the number of elements
+ * @bidi_read_buff: same as above bidi_write_buff but for the bidi read part. can be NULL
+ * @sense: optional sense buffer
+ * @timeout: request timeout in jiffies
+ * @retries: number of times to retry request
+ **/
+int scsi_execute_bidi(struct scsi_device *sdev,
+ unsigned char *cmd, int cmd_len, int data_direction,
+ struct scsi_cmnd_buff *buff, struct scsi_cmnd_buff *bidi_read_buff,
+ char* sense, int timeout, int retries)
+{
+ int ret;
+ struct scsi_execute_bidi_done_t sebd;
+ DECLARE_COMPLETION_ONSTACK(wait);
+ sebd.sense = sense;
+ sebd.waiting = &wait;
+
+ ret = scsi_execute_bidi_async(sdev,cmd, cmd_len, data_direction,
+ buff, bidi_read_buff,timeout, retries,
+ &sebd, scsi_execute_bidi_done, __GFP_WAIT);
+ if (ret)
+ return ret;
+
+ wait_for_completion(&wait);
+
+ return sebd.errors;
+}
+EXPORT_SYMBOL_GPL(scsi_execute_bidi);
/*
* Function: scsi_init_cmd_errh()
@@ -660,6 +772,16 @@ static struct scsi_cmnd *scsi_end_reques
struct request *req = cmd->request;
unsigned long flags;
+ if (is_bidi_cmnd(cmd)) {
+ if ( end_io_error(uptodate) && requeue ) {
+ WARN_ON(bytes);
+ scsi_requeue_command(q, cmd);
+ return NULL;
+ }
+ end_that_request_block(req, uptodate);
+ goto common_code;
+ }
+
/*
* If there are blocks left over at the end, set up the command
* to queue the remainder of them.
@@ -687,6 +809,7 @@ static struct scsi_cmnd *scsi_end_reques
}
}
+common_code:
add_disk_randomness(req->rq_disk);
spin_lock_irqsave(q->queue_lock, flags);
@@ -703,34 +826,34 @@ static struct scsi_cmnd *scsi_end_reques
return NULL;
}
-struct scatterlist *scsi_alloc_sgtable(struct scsi_cmnd *cmd, gfp_t gfp_mask)
+static struct scatterlist *__scsi_alloc_sgtable(struct scsi_data_buffer *sdb, gfp_t gfp_mask)
{
struct scsi_host_sg_pool *sgp;
struct scatterlist *sgl;
- BUG_ON(!cmd->use_sg);
+ BUG_ON(!sdb->use_sg);
- switch (cmd->use_sg) {
+ switch (sdb->use_sg) {
case 1 ... 8:
- cmd->sglist_len = 0;
+ sdb->sglist_len = 0;
break;
case 9 ... 16:
- cmd->sglist_len = 1;
+ sdb->sglist_len = 1;
break;
case 17 ... 32:
- cmd->sglist_len = 2;
+ sdb->sglist_len = 2;
break;
#if (SCSI_MAX_PHYS_SEGMENTS > 32)
case 33 ... 64:
- cmd->sglist_len = 3;
+ sdb->sglist_len = 3;
break;
#if (SCSI_MAX_PHYS_SEGMENTS > 64)
case 65 ... 128:
- cmd->sglist_len = 4;
+ sdb->sglist_len = 4;
break;
#if (SCSI_MAX_PHYS_SEGMENTS > 128)
case 129 ... 256:
- cmd->sglist_len = 5;
+ sdb->sglist_len = 5;
break;
#endif
#endif
@@ -739,11 +862,25 @@ #endif
return NULL;
}
- sgp = scsi_sg_pools + cmd->sglist_len;
+ sgp = scsi_sg_pools + sdb->sglist_len;
sgl = mempool_alloc(sgp->pool, gfp_mask);
return sgl;
}
+struct scatterlist *scsi_alloc_sgtable(struct scsi_cmnd *cmd, gfp_t gfp_mask)
+{
+ struct scsi_data_buffer uni_sdb;
+ struct scatterlist *ret = __scsi_alloc_sgtable(&uni_sdb, gfp_mask);
+
+ if (likely(ret)) {
+ cmd->request_bufflen = uni_sdb.request_bufflen;
+ cmd->request_buffer = uni_sdb.request_buffer;
+ cmd->use_sg = uni_sdb.use_sg;
+ cmd->sglist_len = uni_sdb.sglist_len;
+ }
+ return ret;
+}
+
EXPORT_SYMBOL(scsi_alloc_sgtable);
void scsi_free_sgtable(struct scatterlist *sgl, int index)
@@ -777,7 +914,7 @@ EXPORT_SYMBOL(scsi_free_sgtable);
*/
static void scsi_release_buffers(struct scsi_cmnd *cmd)
{
- if (cmd->use_sg)
+ if (cmd->use_sg && cmd->request_buffer)
scsi_free_sgtable(cmd->request_buffer, cmd->sglist_len);
/*
@@ -786,6 +923,15 @@ static void scsi_release_buffers(struct
*/
cmd->request_buffer = NULL;
cmd->request_bufflen = 0;
+
+ if (is_bidi_cmnd(cmd) && cmd->bidi_read_sdb.request_buffer) {
+ if (cmd->bidi_read_sdb.use_sg)
+ scsi_free_sgtable(
+ cmd->bidi_read_sdb.request_buffer,
+ cmd->bidi_read_sdb.sglist_len);
+ cmd->bidi_read_sdb.request_buffer = NULL;
+ cmd->bidi_read_sdb.request_bufflen = 0;
+ }
}
/*
@@ -850,17 +996,19 @@ void scsi_io_completion(struct scsi_cmnd
memcpy(req->sense, cmd->sense_buffer, len);
req->sense_len = len;
}
- } else
- rq_uni(req)->data_len = cmd->resid;
+ } else {
+ /* FIXME: implement bidi resid */
+ req->uni.data_len = cmd->resid;
+ }
}
/*
* Next deal with any sectors which we were able to correctly
* handle.
*/
- SCSI_LOG_HLCOMPLETE(1, printk("%ld sectors total, "
- "%d bytes done.\n",
- rq_uni(req)->nr_sectors, good_bytes));
+ SCSI_LOG_HLCOMPLETE(1, printk(
+ "%ld(in) sectors %ld(out) sectors total, %d bytes done.\n",
+ rq_in(req)->nr_sectors, rq_out(req)->nr_sectors, good_bytes));
SCSI_LOG_HLCOMPLETE(1, printk("use_sg is %d\n", cmd->use_sg));
if (clear_errors)
@@ -873,6 +1021,8 @@ void scsi_io_completion(struct scsi_cmnd
if (scsi_end_request(cmd, 1, good_bytes, result == 0) == NULL)
return;
+ BUG_ON(is_bidi_cmnd(cmd));
+
/* good_bytes = 0, or (inclusive) there were leftovers and
* result = 0, so scsi_end_request couldn't retry.
*/
@@ -982,19 +1132,24 @@ void scsi_io_completion(struct scsi_cmnd
EXPORT_SYMBOL(scsi_io_completion);
/*
- * Function: scsi_init_io()
+ * Function: scsi_init_data_buf()
*
- * Purpose: SCSI I/O initialize function.
+ * Purpose: SCSI I/O initialize helper.
+ * maps the request buffers into the given sdb.
*
- * Arguments: cmd - Command descriptor we wish to initialize
+ * Arguments: sdb - Command data buff we wish to initialize
+ * req - request to map from
+ * dir - which part of the request to map
*
* Returns: 0 on success
* BLKPREP_DEFER if the failure is retryable
* BLKPREP_KILL if the failure is fatal
*/
-static int scsi_init_io(struct scsi_cmnd *cmd)
+static int scsi_init_data_buff(
+ struct scsi_data_buffer *sdb, struct request* req,
+ enum dma_data_direction dir)
{
- struct request *req = cmd->request;
+ struct request_io_part *req_io = rq_io(req, dir);
struct scatterlist *sgpnt;
int count;
@@ -1003,45 +1158,87 @@ static int scsi_init_io(struct scsi_cmnd
* but now we do (it makes highmem I/O easier to support without
* kmapping pages)
*/
- cmd->use_sg = rq_uni(req)->nr_phys_segments;
+ sdb->use_sg = req_io->nr_phys_segments;
/*
* If sg table allocation fails, requeue request later.
*/
- sgpnt = scsi_alloc_sgtable(cmd, GFP_ATOMIC);
+ sgpnt = __scsi_alloc_sgtable(sdb, GFP_ATOMIC);
if (unlikely(!sgpnt)) {
scsi_unprep_request(req);
return BLKPREP_DEFER;
}
- req->buffer = NULL;
- cmd->request_buffer = (char *) sgpnt;
+ sdb->request_buffer = (char *) sgpnt;
if (blk_pc_request(req))
- cmd->request_bufflen = rq_uni(req)->data_len;
+ sdb->request_bufflen = req_io->data_len;
else
- cmd->request_bufflen = rq_uni(req)->nr_sectors << 9;
+ sdb->request_bufflen = req_io->nr_sectors << 9;
/*
* Next, walk the list, and fill in the addresses and sizes of
* each segment.
*/
- count = blk_rq_map_sg(req->q, req, cmd->request_buffer);
- if (likely(count <= cmd->use_sg)) {
- cmd->use_sg = count;
+ count = blk_rq_map_sg_bidi(req->q, req, sdb->request_buffer, dir);
+ if (likely(count <= sdb->use_sg)) {
+ sdb->use_sg = count;
return BLKPREP_OK;
}
printk(KERN_ERR "Incorrect number of segments after building list\n");
- printk(KERN_ERR "counted %d, received %d\n", count, cmd->use_sg);
- printk(KERN_ERR "req nr_sec %lu, cur_nr_sec %u\n", rq_uni(req)->nr_sectors,
- rq_uni(req)->current_nr_sectors);
+ printk(KERN_ERR "counted %d, received %d\n", count, sdb->use_sg);
+ printk(KERN_ERR "req nr_sec %lu, cur_nr_sec %u\n", req_io->nr_sectors,
+ req_io->current_nr_sectors);
- /* release the command and kill it */
- scsi_release_buffers(cmd);
- scsi_put_command(cmd);
return BLKPREP_KILL;
}
+/*
+ * Function: scsi_init_io()
+ *
+ * Purpose: SCSI I/O initialize function.
+ *
+ * Arguments: cmd - Command descriptor we wish to initialize
+ *
+ * Returns: 0 on success
+ * BLKPREP_DEFER if the failure is retryable
+ * BLKPREP_KILL if the failure is fatal
+ */
+static int scsi_init_io(struct scsi_cmnd *cmd)
+{
+ struct scsi_data_buffer uni_sdb;
+ struct request *req = cmd->request;
+ int error;
+ int is_bidi = is_bidi_cmnd(cmd);
+
+ error = scsi_init_data_buff(&uni_sdb, req,
+ is_bidi ? DMA_TO_DEVICE : rq_dma_dir(req) );
+ if (error)
+ goto err_exit;
+
+ cmd->request_bufflen = uni_sdb.request_bufflen;
+ cmd->request_buffer = uni_sdb.request_buffer;
+ cmd->use_sg = uni_sdb.use_sg;
+ cmd->sglist_len = uni_sdb.sglist_len;
+
+ if (is_bidi) {
+ error = scsi_init_data_buff(&cmd->bidi_read_sdb, req, DMA_FROM_DEVICE);
+ if (error)
+ goto err_exit;
+ }
+
+ req->buffer = NULL;
+ return 0 ;
+
+err_exit:
+ scsi_release_buffers(cmd);
+ if (error == BLKPREP_KILL) {
+ /* release the command and kill it */
+ scsi_put_command(cmd);
+ }
+ return error;
+}
+
static int scsi_issue_flush_fn(request_queue_t *q, struct gendisk *disk,
sector_t *error_sector)
{
@@ -1094,6 +1291,7 @@ static void scsi_blk_pc_done(struct scsi
static int scsi_setup_blk_pc_cmnd(struct scsi_device *sdev, struct request *req)
{
struct scsi_cmnd *cmd;
+ int has_data;
cmd = scsi_get_cmd_from_req(sdev, req);
if (unlikely(!cmd))
@@ -1105,22 +1303,22 @@ static int scsi_setup_blk_pc_cmnd(struct
* that does not transfer data, in which case they may optionally
* submit a request without an attached bio.
*/
- if (rq_uni(req)->bio) {
- int ret;
-
- BUG_ON(!rq_uni(req)->nr_phys_segments);
+ has_data = rq_out(req)->bio || rq_in(req)->bio;
+ if (has_data) {
+ int ret;
+ BUG_ON(rq_bidi_dir(req) && (!rq_out(req)->bio || !rq_in(req)->bio));
ret = scsi_init_io(cmd);
if (unlikely(ret))
return ret;
} else {
- BUG_ON(rq_uni(req)->data_len);
- BUG_ON(req->data);
+ WARN_ON(rq_uni_dir(req) && rq_uni(req)->data_len);
+ WARN_ON(rq_bidi_dir(req));
+ /* FIXME: WARN_ON(rq_dma_dir!=DMA_NONE) */
cmd->request_bufflen = 0;
cmd->request_buffer = NULL;
cmd->use_sg = 0;
- req->buffer = NULL;
req->data_dir = DMA_NONE;
}
@@ -1129,7 +1327,7 @@ static int scsi_setup_blk_pc_cmnd(struct
cmd->cmd_len = req->cmd_len;
cmd->sc_data_direction = rq_dma_dir(req);
- cmd->transfersize = rq_uni(req)->data_len;
+ cmd->transfersize = is_bidi_cmnd(cmd) ? 0 : rq_uni(req)->data_len;
cmd->allowed = req->retries;
cmd->timeout_per_command = req->timeout;
cmd->done = scsi_blk_pc_done;
diff --git a/include/scsi/scsi_cmnd.h b/include/scsi/scsi_cmnd.h
index d6948d0..78ae417 100644
--- a/include/scsi/scsi_cmnd.h
+++ b/include/scsi/scsi_cmnd.h
@@ -1,16 +1,34 @@
#ifndef _SCSI_SCSI_CMND_H
#define _SCSI_SCSI_CMND_H
-#include <linux/dma-mapping.h>
+#include <linux/blkdev.h>
#include <linux/list.h>
#include <linux/types.h>
#include <linux/timer.h>
+#include <scsi/scsi_device.h>
-struct request;
struct scatterlist;
struct Scsi_Host;
struct scsi_device;
+/*
+ * This structure maps data buffers into a scatter-gather list for DMA purposes.
+ * Embedded in struct scsi_cmnd.
+ *
+ * FIXME: We currently embed this structure in scsi_cmnd only for
+ * bidi read buffers. Buffers for uni-directional commands and write
+ * buffers of bidi commands are mapped in a backward compatible way by an
+ * equivalent set of fields, scattered in the scsi_cmnd.
+ * These should be incorporated into an instance of scsi_cmn_sgl.
+ * This will require a major rework of most scsi LLDDs.
+ */
+
+struct scsi_data_buffer {
+ unsigned short use_sg; /* Number of pieces of scatter-gather */
+ unsigned short sglist_len; /* size of malloc'd scatter-gather list */
+ void *request_buffer; /* Actual requested buffer */
+ unsigned request_bufflen; /* Actual request size */
+};
/* embedded in scsi_cmnd */
struct scsi_pointer {
@@ -120,8 +138,41 @@ #define SCSI_SENSE_BUFFERSIZE 96
unsigned char tag; /* SCSI-II queued command tag */
unsigned long pid; /* Process ID, starts at 0. Unique per host. */
+
+ /*
+ * map read buffers of bi-directional commands
+ * iff sc_data_direction==DMA_BIDIRECTIONAL
+ */
+ struct scsi_data_buffer bidi_read_sdb;
};
+#define is_bidi_cmnd(cmd) rq_bidi_dir((cmd)->request)
+
+/*
+ * these inline helpers take into account the scsi cmnd's data direction
+ * to correctly find sg maps for uni-directional and bi-directional commands
+ */
+static inline void
+scsi_get_out_buff(struct scsi_cmnd *sc, struct scsi_cmnd_buff *scb)
+{
+ scb->use_sg = sc->use_sg;
+ scb->buffer = sc->request_buffer;
+ scb->bufflen = sc->request_bufflen;
+}
+
+static inline void
+scsi_get_in_buff(struct scsi_cmnd *sc, struct scsi_cmnd_buff *scb)
+{
+ if (!is_bidi_cmnd(sc)) {
+ scsi_get_out_buff(sc, scb);
+ return;
+ }
+
+ scb->use_sg = sc->bidi_read_sdb.use_sg;
+ scb->buffer = sc->bidi_read_sdb.request_buffer;
+ scb->bufflen = sc->bidi_read_sdb.request_bufflen;
+}
+
extern struct scsi_cmnd *scsi_get_command(struct scsi_device *, gfp_t);
extern struct scsi_cmnd *__scsi_get_command(struct Scsi_Host *, gfp_t);
extern void scsi_put_command(struct scsi_cmnd *);
diff --git a/include/scsi/scsi_device.h b/include/scsi/scsi_device.h
index ebf31b1..a10989c 100644
--- a/include/scsi/scsi_device.h
+++ b/include/scsi/scsi_device.h
@@ -198,6 +198,13 @@ #define transport_class_to_starget(class
#define starget_printk(prefix, starget, fmt, a...) \
dev_printk(prefix, &(starget)->dev, fmt, ##a)
+/* used by APIs as a shorthand for <use_sg, sg, bufflen> */
+struct scsi_cmnd_buff {
+ unsigned short use_sg; /* Number of pieces of scatter-gather */
+ void *buffer; /* if use_sg==0 requested buffer else an sg list */
+ unsigned bufflen; /* Actual request size */
+};
+
extern struct scsi_device *__scsi_add_device(struct Scsi_Host *,
uint, uint, uint, void *hostdata);
extern int scsi_add_device(struct Scsi_Host *host, uint channel,
@@ -297,6 +304,15 @@ extern int scsi_execute_async(struct scs
int timeout, int retries, void *privdata,
void (*done)(void *, char *, int, int),
gfp_t gfp);
+extern int scsi_execute_bidi_async(struct scsi_device *sdev,
+ unsigned char *cmd, int cmd_len, int data_direction,
+ struct scsi_cmnd_buff *buff, struct scsi_cmnd_buff *bidi_read_buff,
+ int timeout, int retries, void *privdata,
+ void (*done)(void *, char *, int, int), gfp_t gfp);
+extern int scsi_execute_bidi(struct scsi_device *sdev,
+ unsigned char *cmd, int cmd_len, int data_direction,
+ struct scsi_cmnd_buff *buff, struct scsi_cmnd_buff *bidi_read_buff,
+ char* sense, int timeout, int retries);
static inline int __must_check scsi_device_reprobe(struct scsi_device *sdev)
{
--
-
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