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| author | Tejun Heo <htejun@gmail.com> | 2011-01-20 13:59:06 +0100 |
|---|---|---|
| committer | Jeff Garzik <jgarzik@redhat.com> | 2011-01-28 09:16:20 +0100 |
| commit | 729a6a300e628a48cf12bac93a964a535e83cd1d (patch) | |
| tree | 716472edea8c210c4f498c742c3c9ea21d546469 /drivers/ata | |
| parent | libata: DVR-212D can't do SETXFER DVD-RW DVR-212D (diff) | |
| download | linux-729a6a300e628a48cf12bac93a964a535e83cd1d.tar.xz linux-729a6a300e628a48cf12bac93a964a535e83cd1d.zip | |
libata: set queue DMA alignment to sector size for ATAPI too
ata_pio_sectors() expects buffer for each sector to be contained in a
single page; otherwise, it ends up overrunning the first page. This
is achieved by setting queue DMA alignment. If sector_size is smaller
than PAGE_SIZE and all buffers are sector_size aligned, buffer for
each sector is always contained in a single page.
This wasn't applied to ATAPI devices but IDENTIFY_PACKET is executed
as ATA_PROT_PIO and thus uses ata_pio_sectors(). Newer versions of
udev issue IDENTIFY_PACKET with unaligned buffer triggering the
problem and causing oops.
This patch fixes the problem by setting sdev->sector_size to
ATA_SECT_SIZE on ATATPI devices and always setting DMA alignment to
sector_size. While at it, add a warning for the unlikely but still
possible scenario where sector_size is larger than PAGE_SIZE, in which
case the alignment wouldn't be enough.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: John Stanley <jpsinthemix@verizon.net>
Tested-by: John Stanley <jpsinthemix@verizon.net>
Cc: stable@kernel.org
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Diffstat (limited to 'drivers/ata')
| -rw-r--r-- | drivers/ata/libata-scsi.c | 24 |
1 files changed, 18 insertions, 6 deletions
diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c index 5defc74973d7..600f6353ecf8 100644 --- a/drivers/ata/libata-scsi.c +++ b/drivers/ata/libata-scsi.c @@ -1099,9 +1099,9 @@ static int ata_scsi_dev_config(struct scsi_device *sdev, struct request_queue *q = sdev->request_queue; void *buf; - /* set the min alignment and padding */ - blk_queue_update_dma_alignment(sdev->request_queue, - ATA_DMA_PAD_SZ - 1); + sdev->sector_size = ATA_SECT_SIZE; + + /* set DMA padding */ blk_queue_update_dma_pad(sdev->request_queue, ATA_DMA_PAD_SZ - 1); @@ -1115,13 +1115,25 @@ static int ata_scsi_dev_config(struct scsi_device *sdev, blk_queue_dma_drain(q, atapi_drain_needed, buf, ATAPI_MAX_DRAIN); } else { - /* ATA devices must be sector aligned */ sdev->sector_size = ata_id_logical_sector_size(dev->id); - blk_queue_update_dma_alignment(sdev->request_queue, - sdev->sector_size - 1); sdev->manage_start_stop = 1; } + /* + * ata_pio_sectors() expects buffer for each sector to not cross + * page boundary. Enforce it by requiring buffers to be sector + * aligned, which works iff sector_size is not larger than + * PAGE_SIZE. ATAPI devices also need the alignment as + * IDENTIFY_PACKET is executed as ATA_PROT_PIO. + */ + if (sdev->sector_size > PAGE_SIZE) + ata_dev_printk(dev, KERN_WARNING, + "sector_size=%u > PAGE_SIZE, PIO may malfunction\n", + sdev->sector_size); + + blk_queue_update_dma_alignment(sdev->request_queue, + sdev->sector_size - 1); + if (dev->flags & ATA_DFLAG_AN) set_bit(SDEV_EVT_MEDIA_CHANGE, sdev->supported_events); |