diff options
| author | Andy Grover <agrover@redhat.com> | 2013-11-11 08:59:17 -0800 |
|---|---|---|
| committer | Nicholas Bellinger <nab@linux-iscsi.org> | 2013-11-12 13:44:54 -0800 |
| commit | 7f7caf6aa74a4f4ad21ebe08bf23b594fce45ca7 (patch) | |
| tree | 058c55e859712486b9f6a8a20f3ea46add3a30eb /drivers/target/target_core_spc.c | |
| parent | f01b9f73392b48c6cda7c2c66594c73137c776da (diff) | |
| download | linux-7f7caf6aa74a4f4ad21ebe08bf23b594fce45ca7.tar.bz2 | |
target: Pass through I/O topology for block backstores
In addition to block size (already implemented), passing through
alignment offset, logical-to-phys block exponent, I/O granularity and
optimal I/O length will allow initiators to properly handle layout on
LUNs with 4K block sizes.
Tested with various weird values via scsi_debug module.
One thing to look at with this patch is the new block limits values --
instead of granularity 1 optimal 8192, Lio will now be returning whatever
the block device says, which may affect performance.
Signed-off-by: Andy Grover <agrover@redhat.com>
Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Diffstat (limited to 'drivers/target/target_core_spc.c')
| -rw-r--r-- | drivers/target/target_core_spc.c | 11 |
1 files changed, 9 insertions, 2 deletions
diff --git a/drivers/target/target_core_spc.c b/drivers/target/target_core_spc.c index 074539558a54..f89a86f29ee3 100644 --- a/drivers/target/target_core_spc.c +++ b/drivers/target/target_core_spc.c @@ -452,6 +452,7 @@ spc_emulate_evpd_b0(struct se_cmd *cmd, unsigned char *buf) struct se_device *dev = cmd->se_dev; u32 max_sectors; int have_tp = 0; + int opt, min; /* * Following spc3r22 section 6.5.3 Block Limits VPD page, when @@ -475,7 +476,10 @@ spc_emulate_evpd_b0(struct se_cmd *cmd, unsigned char *buf) /* * Set OPTIMAL TRANSFER LENGTH GRANULARITY */ - put_unaligned_be16(1, &buf[6]); + if (dev->transport->get_io_min && (min = dev->transport->get_io_min(dev))) + put_unaligned_be16(min / dev->dev_attrib.block_size, &buf[6]); + else + put_unaligned_be16(1, &buf[6]); /* * Set MAXIMUM TRANSFER LENGTH @@ -487,7 +491,10 @@ spc_emulate_evpd_b0(struct se_cmd *cmd, unsigned char *buf) /* * Set OPTIMAL TRANSFER LENGTH */ - put_unaligned_be32(dev->dev_attrib.optimal_sectors, &buf[12]); + if (dev->transport->get_io_opt && (opt = dev->transport->get_io_opt(dev))) + put_unaligned_be32(opt / dev->dev_attrib.block_size, &buf[12]); + else + put_unaligned_be32(dev->dev_attrib.optimal_sectors, &buf[12]); /* * Exit now if we don't support TP. |