From 12b859b70661c5b7d0c37c33f03736b768552e35 Mon Sep 17 00:00:00 2001 From: Ondrej Zary Date: Mon, 3 Jul 2017 03:59:05 -0400 Subject: [PATCH] scsi: g_NCR5380: Fix PDMA transfer size 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 Signed-off-by: Finn Thain Tested-by: Ondrej Zary Signed-off-by: Martin K. Petersen --- 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 c34fc91ba486..fbb28ed0fce8 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); } /* -- 2.45.2