[ide] ide-scsi: simplify+speedup DMA support

* add hwif->sg_mapped flag
* add idescsi_map_sg() converting scsi_cmd->sg into
  hwif->sg_table (this removes need for rq->bio)
* remove code (de)allocating rq->bio
Signed-off-by: default avatarBartlomiej Zolnierkiewicz <bzolnier@gmail.com>
parent ae021d4b
......@@ -680,6 +680,9 @@ void ide_map_sg(ide_drive_t *drive, struct request *rq)
ide_hwif_t *hwif = drive->hwif;
struct scatterlist *sg = hwif->sg_table;
if (hwif->sg_mapped) /* needed by ide-scsi */
return;
if ((rq->flags & REQ_DRIVE_TASKFILE) == 0) {
hwif->sg_nents = blk_rq_map_sg(drive->queue, rq, sg);
} else {
......@@ -1219,12 +1222,15 @@ static ide_startstop_t ide_dma_timeout_retry(ide_drive_t *drive, int error)
HWGROUP(drive)->rq = NULL;
rq->errors = 0;
if (!rq->bio)
goto out;
rq->sector = rq->bio->bi_sector;
rq->current_nr_sectors = bio_iovec(rq->bio)->bv_len >> 9;
rq->hard_cur_sectors = rq->current_nr_sectors;
if (rq->bio)
rq->buffer = NULL;
rq->buffer = NULL;
out:
return ret;
}
......
......@@ -45,6 +45,7 @@
#include <linux/hdreg.h>
#include <linux/slab.h>
#include <linux/ide.h>
#include <linux/scatterlist.h>
#include <asm/io.h>
#include <asm/bitops.h>
......@@ -253,17 +254,6 @@ static inline void idescsi_transform_pc2 (ide_drive_t *drive, idescsi_pc_t *pc)
kfree(atapi_buf);
}
static inline void idescsi_free_bio (struct bio *bio)
{
struct bio *bhp;
while (bio) {
bhp = bio;
bio = bio->bi_next;
bio_put(bhp);
}
}
static void hexdump(u8 *x, int len)
{
int i;
......@@ -421,7 +411,6 @@ static int idescsi_end_request (ide_drive_t *drive, int uptodate, int nrsecs)
spin_lock_irqsave(host->host_lock, flags);
pc->done(pc->scsi_cmd);
spin_unlock_irqrestore(host->host_lock, flags);
idescsi_free_bio(rq->bio);
kfree(pc);
kfree(rq);
scsi->pc = NULL;
......@@ -585,6 +574,50 @@ static ide_startstop_t idescsi_transfer_pc(ide_drive_t *drive)
return ide_started;
}
static inline int idescsi_set_direction(idescsi_pc_t *pc)
{
switch (pc->c[0]) {
case READ_6: case READ_10: case READ_12:
clear_bit(PC_WRITING, &pc->flags);
return 0;
case WRITE_6: case WRITE_10: case WRITE_12:
set_bit(PC_WRITING, &pc->flags);
return 0;
default:
return 1;
}
}
static int idescsi_map_sg(ide_drive_t *drive, idescsi_pc_t *pc)
{
ide_hwif_t *hwif = drive->hwif;
struct scatterlist *sg, *scsi_sg;
int segments;
if (!pc->request_transfer || pc->request_transfer % 1024)
return 1;
if (idescsi_set_direction(pc))
return 1;
sg = hwif->sg_table;
scsi_sg = pc->scsi_cmd->request_buffer;
segments = pc->scsi_cmd->use_sg;
if (segments > hwif->sg_max_nents)
return 1;
if (!segments) {
hwif->sg_nents = 1;
sg_init_one(sg, pc->scsi_cmd->request_buffer, pc->request_transfer);
} else {
hwif->sg_nents = segments;
memcpy(sg, scsi_sg, sizeof(*sg) * segments);
}
return 0;
}
/*
* Issue a packet command
*/
......@@ -594,7 +627,6 @@ static ide_startstop_t idescsi_issue_pc (ide_drive_t *drive, idescsi_pc_t *pc)
ide_hwif_t *hwif = drive->hwif;
atapi_feature_t feature;
atapi_bcount_t bcount;
struct request *rq = pc->rq;
scsi->pc=pc; /* Set the current packet command */
pc->actually_transferred=0; /* We haven't transferred any data yet */
......@@ -602,8 +634,11 @@ static ide_startstop_t idescsi_issue_pc (ide_drive_t *drive, idescsi_pc_t *pc)
bcount.all = min(pc->request_transfer, 63 * 1024); /* Request to transfer the entire buffer at once */
feature.all = 0;
if (drive->using_dma && rq->bio)
if (drive->using_dma && !idescsi_map_sg(drive, pc)) {
hwif->sg_mapped = 1;
feature.b.dma = !hwif->dma_setup(drive);
hwif->sg_mapped = 0;
}
SELECT_DRIVE(drive);
if (IDE_CONTROL_REG)
......@@ -775,81 +810,6 @@ static int idescsi_ioctl (struct scsi_device *dev, int cmd, void __user *arg)
return -EINVAL;
}
static inline struct bio *idescsi_kmalloc_bio (int count)
{
struct bio *bh, *bhp, *first_bh;
if ((first_bh = bhp = bh = bio_alloc(GFP_ATOMIC, 1)) == NULL)
goto abort;
bio_init(bh);
bh->bi_vcnt = 1;
while (--count) {
if ((bh = bio_alloc(GFP_ATOMIC, 1)) == NULL)
goto abort;
bio_init(bh);
bh->bi_vcnt = 1;
bhp->bi_next = bh;
bhp = bh;
bh->bi_next = NULL;
}
return first_bh;
abort:
idescsi_free_bio (first_bh);
return NULL;
}
static inline int idescsi_set_direction (idescsi_pc_t *pc)
{
switch (pc->c[0]) {
case READ_6: case READ_10: case READ_12:
clear_bit (PC_WRITING, &pc->flags);
return 0;
case WRITE_6: case WRITE_10: case WRITE_12:
set_bit (PC_WRITING, &pc->flags);
return 0;
default:
return 1;
}
}
static inline struct bio *idescsi_dma_bio(ide_drive_t *drive, idescsi_pc_t *pc)
{
struct bio *bh = NULL, *first_bh = NULL;
int segments = pc->scsi_cmd->use_sg;
struct scatterlist *sg = pc->scsi_cmd->request_buffer;
if (!drive->using_dma || !pc->request_transfer || pc->request_transfer % 1024)
return NULL;
if (idescsi_set_direction(pc))
return NULL;
if (segments) {
if ((first_bh = bh = idescsi_kmalloc_bio (segments)) == NULL)
return NULL;
#if IDESCSI_DEBUG_LOG
printk ("ide-scsi: %s: building DMA table, %d segments, %dkB total\n", drive->name, segments, pc->request_transfer >> 10);
#endif /* IDESCSI_DEBUG_LOG */
while (segments--) {
bh->bi_io_vec[0].bv_page = sg->page;
bh->bi_io_vec[0].bv_len = sg->length;
bh->bi_io_vec[0].bv_offset = sg->offset;
bh->bi_size = sg->length;
bh = bh->bi_next;
sg++;
}
} else {
if ((first_bh = bh = idescsi_kmalloc_bio (1)) == NULL)
return NULL;
#if IDESCSI_DEBUG_LOG
printk ("ide-scsi: %s: building DMA table for a single buffer (%dkB)\n", drive->name, pc->request_transfer >> 10);
#endif /* IDESCSI_DEBUG_LOG */
bh->bi_io_vec[0].bv_page = virt_to_page(pc->scsi_cmd->request_buffer);
bh->bi_io_vec[0].bv_offset = offset_in_page(pc->scsi_cmd->request_buffer);
bh->bi_io_vec[0].bv_len = pc->request_transfer;
bh->bi_size = pc->request_transfer;
}
return first_bh;
}
static inline int should_transform(ide_drive_t *drive, struct scsi_cmnd *cmd)
{
idescsi_scsi_t *scsi = drive_to_idescsi(drive);
......@@ -921,7 +881,6 @@ static int idescsi_queue (struct scsi_cmnd *cmd,
ide_init_drive_cmd (rq);
rq->special = (char *) pc;
rq->bio = idescsi_dma_bio (drive, pc);
rq->flags = REQ_SPECIAL;
spin_unlock_irq(host->host_lock);
(void) ide_do_drive_cmd (drive, rq, ide_end);
......@@ -975,7 +934,6 @@ static int idescsi_eh_abort (struct scsi_cmnd *cmd)
*/
printk (KERN_ERR "ide-scsi: cmd aborted!\n");
idescsi_free_bio(scsi->pc->rq->bio);
if (scsi->pc->rq->flags & REQ_SENSE)
kfree(scsi->pc->buffer);
kfree(scsi->pc->rq);
......@@ -1024,7 +982,6 @@ static int idescsi_eh_reset (struct scsi_cmnd *cmd)
/* kill current request */
blkdev_dequeue_request(req);
end_that_request_last(req);
idescsi_free_bio(req->bio);
if (req->flags & REQ_SENSE)
kfree(scsi->pc->buffer);
kfree(scsi->pc);
......
......@@ -938,6 +938,7 @@ typedef struct hwif_s {
unsigned no_lba48_dma : 1; /* 1 = cannot do LBA48 DMA */
unsigned no_dsc : 1; /* 0 default, 1 dsc_overlap disabled */
unsigned auto_poll : 1; /* supports nop auto-poll */
unsigned sg_mapped : 1; /* sg_table and sg_nents are ready */
struct device gendev;
struct semaphore gendev_rel_sem; /* To deal with device release() */
......
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