On Mon, 2015-03-30 at 11:01 +0300, Sagi Grimberg wrote:
> On 3/30/2015 6:28 AM, Nicholas A. Bellinger wrote:
> > From: Nicholas Bellinger <nab@xxxxxxxxxxxxxxx>
> >
> > This patch adds WRITE_STRIP support in target_check_write_prot() that
> > invokes sbc_dif_verify_write() for checking T10-PI metadata before
> > submitting the I/O to a backend driver.
> >
> > Upon verify failure, the specific sense code is propigated up the
> > failure path up to transport_generic_request_failure().
> >
> > Also, update sbc_dif_verify_write() to only perform the subsequent
> > protection metadata copy when a valid *sg is passed.
> >
> > Cc: Martin Petersen <martin.petersen@xxxxxxxxxx>
> > Cc: Sagi Grimberg <sagig@xxxxxxxxxxxx>
> > Cc: Christoph Hellwig <hch@xxxxxx>
> > Signed-off-by: Nicholas Bellinger <nab@xxxxxxxxxxxxxxx>
> > ---
> > drivers/target/target_core_sbc.c | 3 +++
> > drivers/target/target_core_transport.c | 16 ++++++++++++++++
> > 2 files changed, 19 insertions(+)
> >
> > diff --git a/drivers/target/target_core_sbc.c b/drivers/target/target_core_sbc.c
> > index 68373c9..ea23b9c 100644
> > --- a/drivers/target/target_core_sbc.c
> > +++ b/drivers/target/target_core_sbc.c
> > @@ -1342,6 +1342,9 @@ sbc_dif_verify_write(struct se_cmd *cmd, sector_t start, unsigned int sectors,
> > kunmap_atomic(paddr);
> > kunmap_atomic(daddr);
> > }
> > + if (!sg)
> > + return 0;
> > +
> > sbc_dif_copy_prot(cmd, sectors, false, sg, sg_off);
> >
> > return 0;
> > diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c
> > index 6a24151..51b62bd 100644
> > --- a/drivers/target/target_core_transport.c
> > +++ b/drivers/target/target_core_transport.c
> > @@ -1740,6 +1740,7 @@ void __target_execute_cmd(struct se_cmd *cmd)
> >
> > static int target_check_write_prot(struct se_cmd *cmd)
> > {
> > + u32 sectors;
> > /*
> > * Perform WRITE_INSERT of PI using software emulation when backend
> > * device has PI enabled, if the transport has not already generated
> > @@ -1750,6 +1751,21 @@ static int target_check_write_prot(struct se_cmd *cmd)
> > if (!(cmd->se_sess->sup_prot_ops & TARGET_PROT_DOUT_INSERT))
> > sbc_dif_generate(cmd);
> > break;
> > + case TARGET_PROT_DOUT_STRIP:
> > + if (cmd->se_sess->sup_prot_ops & TARGET_PROT_DOUT_STRIP)
> > + break;
> > +
> > + sectors = cmd->data_length / cmd->se_dev->dev_attrib.block_size;
>
> Better to use data_length >> ilog2(block_size) and avoiding div in the
> IO path.
>
Done.
> > + cmd->pi_err = sbc_dif_verify_write(cmd, cmd->t_task_lba,
> > + sectors, 0, NULL, 0);
> > + if (cmd->pi_err) {
>
> unlikely()
>
Done.
--
To unsubscribe from this list: send the line "unsubscribe linux-scsi" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
