From 5132d1e655dc4befcc075ef32a261eb9733bb04c Mon Sep 17 00:00:00 2001 From: Nicholas Bellinger Date: Sun, 8 Feb 2015 03:06:17 -0800 Subject: [PATCH] target: Add internal WRITE_STRIP support This patch adds WRITE_STRIP support in target_write_prot_action() 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. (Use ilog2 instead of division and unlikely for pi_err - Sagi) Reviewed-by: Martin Petersen Reviewed-by: Sagi Grimberg Cc: Christoph Hellwig Signed-off-by: Nicholas Bellinger --- 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 67bc1886f004..315ff641408b 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 2a0c36bf3226..0fe58bfabfc2 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_write_prot_action(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_write_prot_action(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 >> ilog2(cmd->se_dev->dev_attrib.block_size); + cmd->pi_err = sbc_dif_verify_write(cmd, cmd->t_task_lba, + sectors, 0, NULL, 0); + if (unlikely(cmd->pi_err)) { + spin_lock_irq(&cmd->t_state_lock); + cmd->transport_state &= ~CMD_T_BUSY|CMD_T_SENT; + spin_unlock_irq(&cmd->t_state_lock); + transport_generic_request_failure(cmd, cmd->pi_err); + return -1; + } + break; default: break; } -- 2.34.1