From: Hans de Goede Date: Sun, 20 Jan 2008 10:12:26 +0000 (+0100) Subject: [SCSI] sd: add fix for devices with last sector access problems X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=a0899d4df534d2bcf671b0f647b809842309a9ae;p=linux-beck.git [SCSI] sd: add fix for devices with last sector access problems This patch adds a new scsi_device flag (last_sector_bug) for devices which contain a bug where the device crashes when the last sector is read in a larger then 1 sector read. This is for example the case with sdcards in the HP PSC1350 printer cardreader and in the HP PSC1610 printer cardreader. Signed-off-by: Hans de Goede Signed-off-by: James Bottomley --- diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c index 212f6bcfd457..24eba3118b5a 100644 --- a/drivers/scsi/sd.c +++ b/drivers/scsi/sd.c @@ -395,6 +395,15 @@ static int sd_prep_fn(struct request_queue *q, struct request *rq) goto out; } + /* + * Some devices (some sdcards for one) don't like it if the + * last sector gets read in a larger then 1 sector read. + */ + if (unlikely(sdp->last_sector_bug && + rq->nr_sectors > sdp->sector_size / 512 && + block + this_count == get_capacity(disk))) + this_count -= sdp->sector_size / 512; + SCSI_LOG_HLQUEUE(2, scmd_printk(KERN_INFO, SCpnt, "block=%llu\n", (unsigned long long)block)); diff --git a/include/scsi/scsi_device.h b/include/scsi/scsi_device.h index e0c645ac5014..3c8f898b160e 100644 --- a/include/scsi/scsi_device.h +++ b/include/scsi/scsi_device.h @@ -139,6 +139,7 @@ struct scsi_device { unsigned fix_capacity:1; /* READ_CAPACITY is too high by 1 */ unsigned guess_capacity:1; /* READ_CAPACITY might be too high by 1 */ unsigned retry_hwerror:1; /* Retry HARDWARE_ERROR */ + unsigned last_sector_bug:1; /* Always read last sector in a 1 sector read */ DECLARE_BITMAP(supported_events, SDEV_EVT_MAXBITS); /* supported events */ struct list_head event_list; /* asserted events */