Re: SCSI breakage on non-cache coherent architectures

Benjamin Herrenschmidt
2007-11-20T03:15:18Z

FYI, Here's what I have for the SCSI change. I haven't updated drivers
to care for the new return code though, help appreciated with that as I
don't know much about these drivers.

Index: linux-work/drivers/scsi/scsi_error.c
===================================================================
--- linux-work.orig/drivers/scsi/scsi_error.c 2007-11-20 13:26:18.000000000 +1100
+++ linux-work/drivers/scsi/scsi_error.c 2007-11-20 13:43:05.000000000 +1100
@@ -602,8 +602,9 @@ static void scsi_abort_eh_cmnd(struct sc
* @cmnd is ignored and this functions sets up a REQUEST_SENSE command
* and cmnd buffers to read @sense_bytes into @scmd->sense_buffer.
**/
-void scsi_eh_prep_cmnd(struct scsi_cmnd *scmd, struct scsi_eh_save *ses,
- unsigned char *cmnd, int cmnd_size, unsigned sense_bytes)
+int scsi_eh_prep_cmnd(struct scsi_cmnd *scmd, struct scsi_eh_save *ses,
+ unsigned char *cmnd, int cmnd_size, unsigned sense_bytes,
+ gfp_t gfp_mask)
{
struct scsi_device *sdev = scmd->device;

@@ -622,12 +623,20 @@ void scsi_eh_prep_cmnd(struct scsi_cmnd
ses->use_sg = scmd->use_sg;
ses->resid = scmd->resid;
ses->result = scmd->result;
+ sg_init_table(&ses->sense_sgl, 1);

if (sense_bytes) {
+ struct page *pg;
+
+ if (sdev->host->hostt->unchecked_isa_dma)
+ gfp_mask |= __GFP_DMA;
scmd->request_bufflen = min_t(unsigned,
sizeof(scmd->sense_buffer), sense_bytes);
- sg_init_one(&ses->sense_sgl, scmd->sense_buffer,
- scmd->request_bufflen);
+ pg = alloc_page(gfp_mask);
+ if (!pg)
+ return FAILED;
+ memset(page_address(pg), 0, scmd->request_bufflen);
+ sg_set_page(&ses->sense_sgl, pg, scmd->request_bufflen, 0);
scmd->request_buffer = &ses->sense_sgl;
scmd->sc_data_direction = DMA_FROM_DEVICE;
scmd->use_sg = 1;
@@ -658,6 +667,8 @@ void scsi_eh_prep_cmnd(struct scsi_cmnd
* untransferred sense data should be interpreted as being zero.
*/
memset(scmd->sense_buffer, 0, sizeof(scmd->sense_buffer));
+
+ return SUCCESS;
}
EXPORT_SYMBOL(scsi_eh_prep_cmnd);

@@ -670,9 +681,17 @@ EXPORT_SYMBOL(scsi_eh_prep_cmnd);
**/
void scsi_eh_restore_cmnd(struct scsi_cmnd* scmd, struct scsi_eh_save *ses)
{
+ struct page *pg;
+
/*
* Restore original data
*/
+ pg = sg_page(&ses->sense_sgl);
+ if (pg) {
+ memcpy(scmd->sense_buffer, page_address(pg),
+ scmd->request_bufflen);
+ __free_page(pg);
+ }
scmd->cmd_len = ses->cmd_len;
memcpy(scmd->cmnd, ses->cmnd, sizeof(scmd->cmnd));
scmd->sc_data_direction = ses->data_direction;
@@ -709,7 +728,10 @@ static int scsi_send_eh_cmnd(struct scsi
struct scsi_eh_save ses;
int rtn;

- scsi_eh_prep_cmnd(scmd, &ses, cmnd, cmnd_size, sense_bytes);
+ if (scsi_eh_prep_cmnd(scmd, &ses, cmnd, cmnd_size, sense_bytes,
+ GFP_KERNEL) != SUCCESS)
+ return FAILED;
+
shost->eh_action = &done;

spin_lock_irqsave(shost->host_lock, flags);
Index: linux-work/include/scsi/scsi_eh.h
===================================================================
--- linux-work.orig/include/scsi/scsi_eh.h 2007-11-20 13:36:44.000000000 +1100
+++ linux-work/include/scsi/scsi_eh.h 2007-11-20 13:42:49.000000000 +1100
@@ -81,9 +81,10 @@ struct scsi_eh_save {
struct scatterlist sense_sgl;
};

-extern void scsi_eh_prep_cmnd(struct scsi_cmnd *scmd,
+extern int scsi_eh_prep_cmnd(struct scsi_cmnd *scmd,
struct scsi_eh_save *ses, unsigned char *cmnd,
- int cmnd_size, unsigned sense_bytes);
+ int cmnd_size, unsigned sense_bytes,
+ gfp_t gfp_mask);

extern void scsi_eh_restore_cmnd(struct scsi_cmnd* scmd,
struct scsi_eh_save *ses);
Index: linux-work/drivers/scsi/NCR5380.c
===================================================================
--- linux-work.orig/drivers/scsi/NCR5380.c 2007-11-20 13:46:41.000000000 +1100
+++ linux-work/drivers/scsi/NCR5380.c 2007-11-20 13:46:47.000000000 +1100
@@ -2283,7 +2283,7 @@ static void NCR5380_information_transfer
}

if ((cmd->cmnd[0] != REQUEST_SENSE) && (status_byte(cmd->SCp.Status) == CHECK_CONDITION)) {
- scsi_eh_prep_cmnd(cmd, &hostdata->ses, NULL, 0, ~0);
+ scsi_eh_prep_cmnd(cmd, &hostdata->ses, NULL, 0, ~0, GFP_ATOMIC);

dprintk(NDEBUG_AUTOSENSE, ("scsi%d : performing request sense\n", instance->host_no));

Index: linux-work/drivers/scsi/atari_NCR5380.c
===================================================================
--- linux-work.orig/drivers/scsi/atari_NCR5380.c 2007-11-20 13:46:55.000000000 +1100
+++ linux-work/drivers/scsi/atari_NCR5380.c 2007-11-20 13:47:00.000000000 +1100
@@ -2240,7 +2240,7 @@ static void NCR5380_information_transfer

if ((cmd->cmnd[0] != REQUEST_SENSE) &&
(status_byte(cmd->SCp.Status) == CHECK_CONDITION)) {
- scsi_eh_prep_cmnd(cmd, &hostdata->ses, NULL, 0, ~0);
+ scsi_eh_prep_cmnd(cmd, &hostdata->ses, NULL, 0, ~0, GFP_ATOMIC);

ASEN_PRINTK("scsi%d: performing request sense\n", HOSTNO);

Index: linux-work/drivers/scsi/sun3_NCR5380.c
===================================================================
--- linux-work.orig/drivers/scsi/sun3_NCR5380.c 2007-11-20 13:46:27.000000000 +1100
+++ linux-work/drivers/scsi/sun3_NCR5380.c 2007-11-20 13:46:33.000000000 +1100
@@ -2261,7 +2261,7 @@ static void NCR5380_information_transfer

if ((cmd->cmnd[0] != REQUEST_SENSE) &&
(status_byte(cmd->SCp.Status) == CHECK_CONDITION)) {
- scsi_eh_prep_cmnd(cmd, &hostdata->ses, NULL, 0, ~0);
+ scsi_eh_prep_cmnd(cmd, &hostdata->ses, NULL, 0, ~0, GFP_ATOMIC);
ASEN_PRINTK("scsi%d: performing request sense\n",
HOSTNO);
/* this is initialized from initialize_SCp