The driver expects that SCSI SGL is a simply array of SG, and itereate
the SGL via integer index. This way is obviously wrong, because of
SG_CHAIN.
Fixes it by using sgl helper.
V2:
- as suggested by Finn Thain, introduce .prv_sg for getting previous
scatterlist pointer
Cc: Christoph Hellwig <h...@lst.de>
Cc: Bart Van Assche <bvanass...@acm.org>
Cc: Ewan D. Milne <emi...@redhat.com>
Cc: Hannes Reinecke <h...@suse.com>
Cc: Finn Thain <fth...@telegraphics.com.au>
Cc: Guenter Roeck <li...@roeck-us.net>
Reported-by: Guenter Roeck <li...@roeck-us.net>
Tested-by: Guenter Roeck <li...@roeck-us.net>
Reviewed-by: Finn Thain <fth...@telegraphics.com.au>
Signed-off-by: Ming Lei <ming....@redhat.com>
---
drivers/scsi/esp_scsi.c | 20 +++++++++++++-------
drivers/scsi/esp_scsi.h | 2 ++
2 files changed, 15 insertions(+), 7 deletions(-)
diff --git a/drivers/scsi/esp_scsi.c b/drivers/scsi/esp_scsi.c
index 76e7ca864d6a..bb88995a12c7 100644
--- a/drivers/scsi/esp_scsi.c
+++ b/drivers/scsi/esp_scsi.c
@@ -371,6 +371,7 @@ static void esp_map_dma(struct esp *esp, struct scsi_cmnd
*cmd)
struct esp_cmd_priv *spriv = ESP_CMD_PRIV(cmd);
struct scatterlist *sg = scsi_sglist(cmd);
int total = 0, i;
+ struct scatterlist *s;
if (cmd->sc_data_direction == DMA_NONE)
return;
@@ -381,16 +382,18 @@ static void esp_map_dma(struct esp *esp, struct scsi_cmnd
*cmd)
* a dma address, so perform an identity mapping.
*/
spriv->num_sg = scsi_sg_count(cmd);
- for (i = 0; i < spriv->num_sg; i++) {
- sg[i].dma_address = (uintptr_t)sg_virt(&sg[i]);
- total += sg_dma_len(&sg[i]);
+
+ scsi_for_each_sg(cmd, s, spriv->num_sg, i) {
+ s->dma_address = (uintptr_t)sg_virt(s);
+ total += sg_dma_len(s);
}
} else {
spriv->num_sg = scsi_dma_map(cmd);
- for (i = 0; i < spriv->num_sg; i++)
- total += sg_dma_len(&sg[i]);
+ scsi_for_each_sg(cmd, s, spriv->num_sg, i)
+ total += sg_dma_len(s);
}
spriv->cur_residue = sg_dma_len(sg);
+ spriv->prv_sg = NULL;
spriv->cur_sg = sg;
spriv->tot_residue = total;
}
@@ -444,7 +447,8 @@ static void esp_advance_dma(struct esp *esp, struct
esp_cmd_entry *ent,
p->tot_residue = 0;
}
if (!p->cur_residue && p->tot_residue) {
- p->cur_sg++;
+ p->prv_sg = p->cur_sg;
+ p->cur_sg = sg_next(p->cur_sg);
p->cur_residue = sg_dma_len(p->cur_sg);
}
}
@@ -465,6 +469,7 @@ static void esp_save_pointers(struct esp *esp, struct
esp_cmd_entry *ent)
return;
}
ent->saved_cur_residue = spriv->cur_residue;
+ ent->saved_prv_sg = spriv->prv_sg;
ent->saved_cur_sg = spriv->cur_sg;
ent->saved_tot_residue = spriv->tot_residue;
}
@@ -479,6 +484,7 @@ static void esp_restore_pointers(struct esp *esp, struct
esp_cmd_entry *ent)
return;
}
spriv->cur_residue = ent->saved_cur_residue;
+ spriv->prv_sg = ent->saved_prv_sg;
spriv->cur_sg = ent->saved_cur_sg;
spriv->tot_residue = ent->saved_tot_residue;
}
@@ -1647,7 +1653,7 @@ static int esp_msgin_process(struct esp *esp)
spriv = ESP_CMD_PRIV(ent->cmd);
if (spriv->cur_residue == sg_dma_len(spriv->cur_sg)) {
- spriv->cur_sg--;
+ spriv->cur_sg = spriv->prv_sg;
spriv->cur_residue = 1;
} else
spriv->cur_residue++;
diff --git a/drivers/scsi/esp_scsi.h b/drivers/scsi/esp_scsi.h
index aa87a6b72dcc..91b32f2a1a1b 100644
--- a/drivers/scsi/esp_scsi.h
+++ b/drivers/scsi/esp_scsi.h
@@ -251,6 +251,7 @@
struct esp_cmd_priv {
int num_sg;
int cur_residue;
+ struct scatterlist *prv_sg;
struct scatterlist *cur_sg;
int tot_residue;
};
@@ -273,6 +274,7 @@ struct esp_cmd_entry {
struct scsi_cmnd *cmd;
unsigned int saved_cur_residue;
+ struct scatterlist *saved_prv_sg;
struct scatterlist *saved_cur_sg;
unsigned int saved_tot_residue;
--
2.20.1
