From: Nicholas Bellinger <[email protected]> After COMPARE_AND_WRITE completes it's comparision, the WRITE payload SGLs head expect to be updated to point from the verify instance of user data, to the write instance of user data.
So for this special case, add transport_reset_sgl_orig() usage within transport_free_pages() and add se_cmd->t_data_[sg,nents]_orig members to save the original assignments. Cc: Christoph Hellwig <[email protected]> Cc: Hannes Reinecke <[email protected]> Cc: Martin Petersen <[email protected]> Cc: Chris Mason <[email protected]> Cc: James Bottomley <[email protected]> Cc: Nicholas Bellinger <[email protected]> Signed-off-by: Nicholas Bellinger <[email protected]> --- drivers/target/target_core_transport.c | 21 ++++++++++++++++++++- include/target/target_core_base.h | 2 ++ 2 files changed, 22 insertions(+), 1 deletion(-) diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c index 60d1336..bb98684 100644 --- a/drivers/target/target_core_transport.c +++ b/drivers/target/target_core_transport.c @@ -1994,10 +1994,29 @@ static inline void transport_free_sgl(struct scatterlist *sgl, int nents) kfree(sgl); } +static inline void transport_reset_sgl_orig(struct se_cmd *cmd) +{ + /* + * Check for saved t_data_sg that may be used for COMPARE_AND_WRITE + * emulation, and free + reset pointers if necessary.. + */ + if (!cmd->t_data_sg_orig) + return; + + kfree(cmd->t_data_sg); + cmd->t_data_sg = cmd->t_data_sg_orig; + cmd->t_data_sg_orig = NULL; + cmd->t_data_nents = cmd->t_data_nents_orig; + cmd->t_data_nents_orig = 0; +} + static inline void transport_free_pages(struct se_cmd *cmd) { - if (cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) + if (cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) { + transport_reset_sgl_orig(cmd); return; + } + transport_reset_sgl_orig(cmd); transport_free_sgl(cmd->t_data_sg, cmd->t_data_nents); cmd->t_data_sg = NULL; diff --git a/include/target/target_core_base.h b/include/target/target_core_base.h index e1e0843..2f9a438 100644 --- a/include/target/target_core_base.h +++ b/include/target/target_core_base.h @@ -476,7 +476,9 @@ struct se_cmd { struct work_struct work; struct scatterlist *t_data_sg; + struct scatterlist *t_data_sg_orig; unsigned int t_data_nents; + unsigned int t_data_nents_orig; void *t_data_vmap; struct scatterlist *t_bidi_data_sg; unsigned int t_bidi_data_nents; -- 1.7.10.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
