From 3b300af62d85512d019b870d9450b093ddf1dcaf Mon Sep 17 00:00:00 2001 From: Mark Rustad Date: Tue, 3 Apr 2012 10:24:41 -0700 Subject: [PATCH] tcm_fc: Add abort flag for gracefully handling exchange timeout BugLink: http://bugs.launchpad.net/bugs/981162 commit e1c4038282c7586c3544542b37872c434669d3ac upstream. Add abort flag and use it to terminate processing when an exchange is timed out or is reset. The abort flag is used in place of the transport_generic_free_cmd function call in the reset and timeout cases, because calling that function in that context would free memory that was in use. The aborted flag allows the lifetime to be managed in a more normal way, while truncating the processing. This change eliminates a source of memory corruption which manifested in a variety of ugly ways. (nab: Drop unused struct fc_exch *ep in ft_recv_seq) Signed-off-by: Mark Rustad Acked-by: Kiran Patil Signed-off-by: Nicholas Bellinger Signed-off-by: Greg Kroah-Hartman Signed-off-by: Leann Ogasawara Signed-off-by: Tim Gardner --- drivers/target/tcm_fc/tcm_fc.h | 1 + drivers/target/tcm_fc/tfc_cmd.c | 10 ++++++++-- drivers/target/tcm_fc/tfc_io.c | 2 ++ 3 files changed, 11 insertions(+), 2 deletions(-) diff --git a/drivers/target/tcm_fc/tcm_fc.h b/drivers/target/tcm_fc/tcm_fc.h index e05c551..be7ed12 100644 --- a/drivers/target/tcm_fc/tcm_fc.h +++ b/drivers/target/tcm_fc/tcm_fc.h @@ -124,6 +124,7 @@ struct ft_cmd { /* Local sense buffer */ unsigned char ft_sense_buffer[TRANSPORT_SENSE_BUFFER]; u32 was_ddp_setup:1; /* Set only if ddp is setup */ + u32 aborted:1; /* Set if aborted by reset or timeout */ struct scatterlist *sg; /* Set only if DDP is setup */ u32 sg_cnt; /* No. of item in scatterlist */ }; diff --git a/drivers/target/tcm_fc/tfc_cmd.c b/drivers/target/tcm_fc/tfc_cmd.c index 754b669..d95cfe2 100644 --- a/drivers/target/tcm_fc/tfc_cmd.c +++ b/drivers/target/tcm_fc/tfc_cmd.c @@ -130,6 +130,8 @@ int ft_queue_status(struct se_cmd *se_cmd) struct fc_exch *ep; size_t len; + if (cmd->aborted) + return 0; ft_dump_cmd(cmd, __func__); ep = fc_seq_exch(cmd->seq); lport = ep->lp; @@ -196,6 +198,8 @@ int ft_write_pending(struct se_cmd *se_cmd) ft_dump_cmd(cmd, __func__); + if (cmd->aborted) + return 0; ep = fc_seq_exch(cmd->seq); lport = ep->lp; fp = fc_frame_alloc(lport, sizeof(*txrdy)); @@ -266,10 +270,10 @@ static void ft_recv_seq(struct fc_seq *sp, struct fc_frame *fp, void *arg) struct ft_cmd *cmd = arg; struct fc_frame_header *fh; - if (IS_ERR(fp)) { + if (unlikely(IS_ERR(fp))) { /* XXX need to find cmd if queued */ cmd->seq = NULL; - transport_generic_free_cmd(&cmd->se_cmd, 0); + cmd->aborted = true; return; } @@ -447,6 +451,8 @@ int ft_queue_tm_resp(struct se_cmd *se_cmd) struct se_tmr_req *tmr = se_cmd->se_tmr_req; enum fcp_resp_rsp_codes code; + if (cmd->aborted) + return 0; switch (tmr->response) { case TMR_FUNCTION_COMPLETE: code = FCP_TMF_CMPL; diff --git a/drivers/target/tcm_fc/tfc_io.c b/drivers/target/tcm_fc/tfc_io.c index 1369b1c..ada131c 100644 --- a/drivers/target/tcm_fc/tfc_io.c +++ b/drivers/target/tcm_fc/tfc_io.c @@ -84,6 +84,8 @@ int ft_queue_data_in(struct se_cmd *se_cmd) void *from; void *to = NULL; + if (cmd->aborted) + return 0; ep = fc_seq_exch(cmd->seq); lport = ep->lp; cmd->seq = lport->tt.seq_start_next(cmd->seq); -- 1.7.10.4