diff options
| author | Tejun Heo <htejun@gmail.com> | 2011-01-20 13:59:06 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2011-05-09 16:04:46 -0700 |
| commit | c64507d3285593809167ad35fa738660d197d851 (patch) | |
| tree | 664d72ec957d149189acf459af87e31e7d849100 /drivers | |
| parent | 3fb5680bb06699973cdee064ab737798bd5b8add (diff) | |
libata: set queue DMA alignment to sector size for ATAPI too
commit 729a6a300e628a48cf12bac93a964a535e83cd1d upstream.
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>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Signed-off-by: Jonathan Liu <net147@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers')
| -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 551662456c5..89c0b0645f7 100644 --- a/drivers/ata/libata-scsi.c +++ b/drivers/ata/libata-scsi.c @@ -1099,13 +1099,13 @@ static int ata_scsi_dev_config(struct scsi_device *sdev, /* configure max sectors */ blk_queue_max_sectors(sdev->request_queue, dev->max_sectors); + sdev->sector_size = ATA_SECT_SIZE; + if (dev->class == ATA_DEV_ATAPI) { 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); + /* set DMA padding */ blk_queue_update_dma_pad(sdev->request_queue, ATA_DMA_PAD_SZ - 1); @@ -1119,12 +1119,24 @@ 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 */ - blk_queue_update_dma_alignment(sdev->request_queue, - ATA_SECT_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); |