Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > linux.kernel > #1666694

[PATCH 1/4] g_NCR5380: Fix PDMA transfer size

From Finn Thain <fthain@telegraphics.com.au>
Newsgroups linux.kernel
Subject [PATCH 1/4] g_NCR5380: Fix PDMA transfer size
Date 2017-06-15 14:30 +0200
Message-ID <tSC4p-2pM-11@gated-at.bofh.it> (permalink)
References <tSC4p-2pM-3@gated-at.bofh.it>
Organization linux.* mail to news gateway

Show all headers | View raw


From: Ondrej Zary <linux@rainbow-software.org>

generic_NCR5380_dma_xfer_len() incorrectly uses cmd->transfersize
which causes rescan-scsi-bus and CD-ROM access to hang the system.
Use cmd->SCp.this_residual instead, like other NCR5380 drivers.

Signed-off-by: Ondrej Zary <linux@rainbow-software.org>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
---
 drivers/scsi/g_NCR5380.c | 12 +++---------
 1 file changed, 3 insertions(+), 9 deletions(-)

diff --git a/drivers/scsi/g_NCR5380.c b/drivers/scsi/g_NCR5380.c
index 67c8dac321ad..14ef4e8c4713 100644
--- a/drivers/scsi/g_NCR5380.c
+++ b/drivers/scsi/g_NCR5380.c
@@ -76,6 +76,7 @@
 #define IRQ_AUTO 254
 
 #define MAX_CARDS 8
+#define DMA_MAX_SIZE 32768
 
 /* old-style parameters for compatibility */
 static int ncr_irq = -1;
@@ -629,23 +630,16 @@ static inline int generic_NCR5380_pwrite(struct NCR5380_hostdata *hostdata,
 static int generic_NCR5380_dma_xfer_len(struct NCR5380_hostdata *hostdata,
                                         struct scsi_cmnd *cmd)
 {
-	int transfersize = cmd->transfersize;
+	int transfersize = cmd->SCp.this_residual;
 
 	if (hostdata->flags & FLAG_NO_PSEUDO_DMA)
 		return 0;
 
-	/* Limit transfers to 32K, for xx400 & xx406
-	 * pseudoDMA that transfers in 128 bytes blocks.
-	 */
-	if (transfersize > 32 * 1024 && cmd->SCp.this_residual &&
-	    !(cmd->SCp.this_residual % transfersize))
-		transfersize = 32 * 1024;
-
 	/* 53C400 datasheet: non-modulo-128-byte transfers should use PIO */
 	if (transfersize % 128)
 		transfersize = 0;
 
-	return transfersize;
+	return min(transfersize, DMA_MAX_SIZE);
 }
 
 /*
-- 
2.13.0

Back to linux.kernel | Previous | NextPrevious in thread | Next in thread | Find similar | Unroll thread


Thread

[PATCH 0/4] g_NCR5380: PDMA fixes and cleanup Finn Thain <fthain@telegraphics.com.au> - 2017-06-15 14:30 +0200
  [PATCH 2/4] g_NCR5380: End PDMA transfer correctly on target  disconnection Finn Thain <fthain@telegraphics.com.au> - 2017-06-15 14:30 +0200
  [PATCH 1/4] g_NCR5380: Fix PDMA transfer size Finn Thain <fthain@telegraphics.com.au> - 2017-06-15 14:30 +0200
  [PATCH 3/4] g_NCR5380: Limit sg_tablesize to avoid PDMA read overruns  on DTC436 Finn Thain <fthain@telegraphics.com.au> - 2017-06-15 14:30 +0200
  [PATCH 4/4] g_NCR5380: Cleanup comments and whitespace Finn Thain <fthain@telegraphics.com.au> - 2017-06-15 14:30 +0200

csiph-web