Re: [PATCH rc8-mm1] hotfix libata-scsi corruption
From: Jeff Garzik <hidden>
Date: 2008-01-22 20:32:40
Also in:
linux-scsi, lkml
James Bottomley wrote:
quoted hunk ↗ jump to hunk
Actually, I don't think it's a smaller I/O issue. The SMART protocol specifically mandates that the transfers for SMART READ DATA and SMART READ LOG shall be 512 bytes). However, the pio transfer routine does seem to be assuming sector alignment as well, which will be where your problems are coming from. I think we need to specify sector minimum alignment for ata (but not atapi, which has its own non sector size pio routine). How about the attached? We have to do this for all ATA devices, because they'll likely all support SMART, and SMART is defined to be a PIO command. James ---diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c index 4bb268b..bc5cf6b 100644 --- a/drivers/ata/libata-scsi.c +++ b/drivers/ata/libata-scsi.c@@ -824,9 +824,6 @@ static void ata_scsi_sdev_config(struct scsi_device *sdev) * requests. */ sdev->max_device_blocked = 1; - - /* set the min alignment */ - blk_queue_update_dma_alignment(sdev->request_queue, ATA_DMA_PAD_SZ - 1); } static void ata_scsi_dev_config(struct scsi_device *sdev,@@ -842,7 +839,14 @@ static void ata_scsi_dev_config(struct scsi_device *sdev, if (dev->class == ATA_DEV_ATAPI) { struct request_queue *q = sdev->request_queue; blk_queue_max_hw_segments(q, q->max_hw_segments - 1); - } + + /* set the min alignment */ + blk_queue_update_dma_alignment(sdev->request_queue, + ATA_DMA_PAD_SZ - 1); + } else + /* ATA devices must be sector aligned */ + blk_queue_update_dma_alignment(sdev->request_queue, + ATA_SECT_SIZE - 1); if (dev->flags & ATA_DFLAG_AN) set_bit(SDEV_EVT_MEDIA_CHANGE, sdev->supported_events);
ACK Unlike ATAPI, ATA is indeed all 512-byte alignment transfers (_not_ sector size, which may or may not be 512 bytes) Does this apply to libata? libata + jejb dma alignment patch? What tree... Jeff