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| author | Tejun Heo <htejun@gmail.com> | 2006-11-11 20:10:45 +0900 |
|---|---|---|
| committer | Jeff Garzik <jeff@garzik.org> | 2006-12-01 22:45:54 -0500 |
| commit | 6fc49adb9417b9c793e8f88d485387bb89ceb733 (patch) | |
| tree | d94f536f24e504b1a654c392171fb6f08a195ca2 /drivers/ata/libata-scsi.c | |
| parent | 648a88be4a016d2637ace3ae74b85a0512255ee8 (diff) | |
| download | op-kernel-dev-6fc49adb9417b9c793e8f88d485387bb89ceb733.zip op-kernel-dev-6fc49adb9417b9c793e8f88d485387bb89ceb733.tar.gz | |
[PATCH] libata: use FLUSH_EXT only when driver is larger than LBA28 limit
Many drives support LBA48 even when its capacity is smaller than
1<<28, as LBA48 is required for many functionalities. FLUSH_EXT is
mandatory for drives w/ LBA48 support.
Interestingly, at least one of such drives (ST960812A) has problems
dealing with FLUSH_EXT. It eventually completes the command but takes
around 7 seconds to finish in many cases thus drastically slowing down
IO transactions. This seems to be a firmware bug which sneaked into
production probably because no other ATA driver including linux IDE
issues FLUSH_EXT to drives which report support for LBA48 & FLUSH_EXT
but is smaller than 1<<28 blocks.
This patch adds ATA_DFLAG_FLUSH_EXT which is set iff the drive
supports LBA48 & FLUSH_EXT and is larger than LBA28 limit. Both cache
flush paths are updated to issue FLUSH_EXT only when the flag is set.
Note that the changed behavior is more inline with the rest of libata.
libata prefers shorter commands whenever possible.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: Danny Kukawka <dkukawka@novell.com>
Cc: Stefan Seyfried <seife@novell.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Diffstat (limited to 'drivers/ata/libata-scsi.c')
| -rw-r--r-- | drivers/ata/libata-scsi.c | 3 |
1 files changed, 1 insertions, 2 deletions
diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c index f13dd07..7a55c2e4 100644 --- a/drivers/ata/libata-scsi.c +++ b/drivers/ata/libata-scsi.c @@ -1027,8 +1027,7 @@ static unsigned int ata_scsi_flush_xlat(struct ata_queued_cmd *qc, const u8 *scs tf->flags |= ATA_TFLAG_DEVICE; tf->protocol = ATA_PROT_NODATA; - if ((qc->dev->flags & ATA_DFLAG_LBA48) && - (ata_id_has_flush_ext(qc->dev->id))) + if (qc->dev->flags & ATA_DFLAG_FLUSH_EXT) tf->command = ATA_CMD_FLUSH_EXT; else tf->command = ATA_CMD_FLUSH; |
