From 135932651fd1eeb95eb6c5d4f6652aae73fe2c24 Mon Sep 17 00:00:00 2001 From: Jeff Garzik Date: Sat, 27 Aug 2005 04:20:12 -0400 Subject: [PATCH] [libata scsi] fix read/write translation edge cases Fix bugs for unlikely edge cases noticed by Douglas Gilbert: - When READ(6)/WRITE(6) sector count == 0, treat it as 256 sectors - For other READ(x)/WRITE(x), when sector count == 0, error. We don't support successfully completing zero-length transfers at this time. --- drivers/scsi/libata-scsi.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/drivers/scsi/libata-scsi.c b/drivers/scsi/libata-scsi.c index f58311b8c050..4074e7877ba3 100644 --- a/drivers/scsi/libata-scsi.c +++ b/drivers/scsi/libata-scsi.c @@ -630,11 +630,19 @@ static unsigned int ata_scsi_rw_xlat(struct ata_queued_cmd *qc, u8 *scsicmd) tf->lbah = scsicmd[3]; VPRINTK("ten-byte command\n"); + if (qc->nsect == 0) /* we don't support length==0 cmds */ + return 1; return 0; } if (scsicmd[0] == READ_6 || scsicmd[0] == WRITE_6) { qc->nsect = tf->nsect = scsicmd[4]; + if (!qc->nsect) { + qc->nsect = 256; + if (lba48) + tf->hob_nsect = 1; + } + tf->lbal = scsicmd[3]; tf->lbam = scsicmd[2]; tf->lbah = scsicmd[1] & 0x1f; /* mask out reserved bits */ @@ -674,6 +682,8 @@ static unsigned int ata_scsi_rw_xlat(struct ata_queued_cmd *qc, u8 *scsicmd) tf->lbah = scsicmd[7]; VPRINTK("sixteen-byte command\n"); + if (qc->nsect == 0) /* we don't support length==0 cmds */ + return 1; return 0; } -- 2.20.1