linux/drivers/firewire
Martin K. Petersen 5db44863b6 [SCSI] sd: Implement support for WRITE SAME
Implement support for WRITE SAME(10) and WRITE SAME(16) in the SCSI disk
driver.

 - We set the default maximum to 0xFFFF because there are several
   devices out there that only support two-byte block counts even with
   WRITE SAME(16). We only enable transfers bigger than 0xFFFF if the
   device explicitly reports MAXIMUM WRITE SAME LENGTH in the BLOCK
   LIMITS VPD.

 - max_write_same_blocks can be overriden per-device basis in sysfs.

 - The UNMAP discovery heuristics remain unchanged but the discard
   limits are tweaked to match the "real" WRITE SAME commands.

 - In the error handling logic we now distinguish between WRITE SAME
   with and without UNMAP set.

The discovery process heuristics are:

 - If the device reports a SCSI level of SPC-3 or greater we'll issue
   READ SUPPORTED OPERATION CODES to find out whether WRITE SAME(16) is
   supported. If that's the case we will use it.

 - If the device supports the block limits VPD and reports a MAXIMUM
   WRITE SAME LENGTH bigger than 0xFFFF we will use WRITE SAME(16).

 - Otherwise we will use WRITE SAME(10) unless the target LBA is beyond
   0xFFFFFFFF or the block count exceeds 0xFFFF.

 - no_write_same is set for ATA, FireWire and USB.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Mike Snitzer <snitzer@redhat.com>
Reviewed-by: Jeff Garzik <jgarzik@redhat.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-11-13 22:45:42 -08:00
..
core-card.c IEEE 1394 (FireWire) subsystem updates post v3.4: 2012-05-24 12:57:47 -07:00
core-cdev.c firewire: cdev: fix user memory corruption (i386 userland on amd64 kernel) 2012-10-09 18:26:28 +02:00
core-device.c firewire: core: feed /dev/random with devices' GUIDs 2012-09-25 16:18:17 +02:00
core-iso.c firewire: core: fix multichannel IR with buffers larger than 2 GB 2012-06-17 19:35:26 +02:00
core-topology.c Remove all #inclusions of asm/system.h 2012-03-28 18:30:03 +01:00
core-transaction.c firewire: addendum to address handler RCU conversion 2012-09-28 11:47:42 +02:00
core.h IEEE 1394 (FireWire) subsystem updates post v3.4: 2012-05-24 12:57:47 -07:00
init_ohci1394_dma.c ieee1394: move init_ohci1394_dma to drivers/firewire/ 2010-10-11 14:48:03 +02:00
Kconfig firewire: ohci: move runtime debug facility out of #ifdef 2012-03-10 17:41:19 +01:00
Makefile ieee1394: move init_ohci1394_dma to drivers/firewire/ 2010-10-11 14:48:03 +02:00
net.c firewire: net: use dev_printk API 2012-02-22 22:36:00 +01:00
nosy-user.h firewire: nosy: endianess fixes and annotations 2010-07-27 11:04:11 +02:00
nosy.c firewire: use module_pci_driver 2012-04-09 14:23:37 +02:00
nosy.h firewire: nosy: misc cleanups 2010-07-27 11:04:10 +02:00
ohci.c firewire: ohci: get IR bit from TSB41BA3D phy 2012-09-25 16:18:17 +02:00
ohci.h firewire: ohci: fix TI TSB82AA2 regression since 2.6.35 2010-10-17 14:09:12 +02:00
sbp2.c [SCSI] sd: Implement support for WRITE SAME 2012-11-13 22:45:42 -08:00