diff options
| 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 /include | |
| parent | 648a88be4a016d2637ace3ae74b85a0512255ee8 (diff) | |
[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 'include')
| -rw-r--r-- | include/linux/libata.h | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/include/linux/libata.h b/include/linux/libata.h index 0d0ddeaee73..36e233cc388 100644 --- a/include/linux/libata.h +++ b/include/linux/libata.h @@ -140,6 +140,7 @@ enum { ATA_DFLAG_LBA48 = (1 << 1), /* device supports LBA48 */ ATA_DFLAG_CDB_INTR = (1 << 2), /* device asserts INTRQ when ready for CDB */ ATA_DFLAG_NCQ = (1 << 3), /* device supports NCQ */ + ATA_DFLAG_FLUSH_EXT = (1 << 4), /* do FLUSH_EXT instead of FLUSH */ ATA_DFLAG_CFG_MASK = (1 << 8) - 1, ATA_DFLAG_PIO = (1 << 8), /* device limited to PIO mode */ |