From 507384209371fc25cab203b95e7bdf50e58b47d5 Mon Sep 17 00:00:00 2001 From: James Smart Date: Tue, 1 Aug 2017 15:12:40 -0700 Subject: [PATCH] lpfc: support nvmet_fc defer_rcv callback Currently, calls to nvmet_fc_rcv_fcp_req() always copied the FC-NVME cmd iu to a temporary buffer before returning, allowing the driver to immediately repost the buffer to the hardware. To address timing conditions on queue element structures vs async command reception, the nvmet_fc transport occasionally may need to hold on to the command iu buffer for a short period. In these cases, the nvmet_fc_rcv_fcp_req() will return a special return code (-EOVERFLOW). In these cases, the LLDD must delay until the new defer_rcv lldd callback is called before recycling the buffer back to the hw. This patch adds support for the new nvmet_fc transport defer_rcv callback and recognition of the new error code when passing commands to the transport. Signed-off-by: Dick Kennedy Signed-off-by: James Smart Signed-off-by: Christoph Hellwig --- drivers/scsi/lpfc/lpfc_attr.c | 4 +++- drivers/scsi/lpfc/lpfc_debugfs.c | 5 ++++- drivers/scsi/lpfc/lpfc_nvmet.c | 30 ++++++++++++++++++++++++++++++ drivers/scsi/lpfc/lpfc_nvmet.h | 1 + 4 files changed, 38 insertions(+), 2 deletions(-) diff --git a/drivers/scsi/lpfc/lpfc_attr.c b/drivers/scsi/lpfc/lpfc_attr.c index 4ed48ed38e79..7ee1a94c0b33 100644 --- a/drivers/scsi/lpfc/lpfc_attr.c +++ b/drivers/scsi/lpfc/lpfc_attr.c @@ -205,8 +205,10 @@ lpfc_nvme_info_show(struct device *dev, struct device_attribute *attr, atomic_read(&tgtp->xmt_ls_rsp_error)); len += snprintf(buf+len, PAGE_SIZE-len, - "FCP: Rcv %08x Release %08x Drop %08x\n", + "FCP: Rcv %08x Defer %08x Release %08x " + "Drop %08x\n", atomic_read(&tgtp->rcv_fcp_cmd_in), + atomic_read(&tgtp->rcv_fcp_cmd_defer), atomic_read(&tgtp->xmt_fcp_release), atomic_read(&tgtp->rcv_fcp_cmd_drop)); diff --git a/drivers/scsi/lpfc/lpfc_debugfs.c b/drivers/scsi/lpfc/lpfc_debugfs.c index 5cc8b0f7d885..744f3f395b64 100644 --- a/drivers/scsi/lpfc/lpfc_debugfs.c +++ b/drivers/scsi/lpfc/lpfc_debugfs.c @@ -782,8 +782,11 @@ lpfc_debugfs_nvmestat_data(struct lpfc_vport *vport, char *buf, int size) atomic_read(&tgtp->xmt_ls_rsp_error)); len += snprintf(buf + len, size - len, - "FCP: Rcv %08x Drop %08x\n", + "FCP: Rcv %08x Defer %08x Release %08x " + "Drop %08x\n", atomic_read(&tgtp->rcv_fcp_cmd_in), + atomic_read(&tgtp->rcv_fcp_cmd_defer), + atomic_read(&tgtp->xmt_fcp_release), atomic_read(&tgtp->rcv_fcp_cmd_drop)); if (atomic_read(&tgtp->rcv_fcp_cmd_in) != diff --git a/drivers/scsi/lpfc/lpfc_nvmet.c b/drivers/scsi/lpfc/lpfc_nvmet.c index fbeec344c6cc..bbbd0f84160d 100644 --- a/drivers/scsi/lpfc/lpfc_nvmet.c +++ b/drivers/scsi/lpfc/lpfc_nvmet.c @@ -841,12 +841,31 @@ lpfc_nvmet_xmt_fcp_release(struct nvmet_fc_target_port *tgtport, lpfc_nvmet_ctxbuf_post(phba, ctxp->ctxbuf); } +static void +lpfc_nvmet_defer_rcv(struct nvmet_fc_target_port *tgtport, + struct nvmefc_tgt_fcp_req *rsp) +{ + struct lpfc_nvmet_tgtport *tgtp; + struct lpfc_nvmet_rcv_ctx *ctxp = + container_of(rsp, struct lpfc_nvmet_rcv_ctx, ctx.fcp_req); + struct rqb_dmabuf *nvmebuf = ctxp->rqb_buffer; + struct lpfc_hba *phba = ctxp->phba; + + lpfc_nvmeio_data(phba, "NVMET DEFERRCV: xri x%x sz %d CPU %02x\n", + ctxp->oxid, ctxp->size, smp_processor_id()); + + tgtp = phba->targetport->private; + atomic_inc(&tgtp->rcv_fcp_cmd_defer); + lpfc_rq_buf_free(phba, &nvmebuf->hbuf); /* repost */ +} + static struct nvmet_fc_target_template lpfc_tgttemplate = { .targetport_delete = lpfc_nvmet_targetport_delete, .xmt_ls_rsp = lpfc_nvmet_xmt_ls_rsp, .fcp_op = lpfc_nvmet_xmt_fcp_op, .fcp_abort = lpfc_nvmet_xmt_fcp_abort, .fcp_req_release = lpfc_nvmet_xmt_fcp_release, + .defer_rcv = lpfc_nvmet_defer_rcv, .max_hw_queues = 1, .max_sgl_segments = LPFC_NVMET_DEFAULT_SEGS, @@ -1504,6 +1523,17 @@ lpfc_nvmet_unsol_fcp_buffer(struct lpfc_hba *phba, return; } + /* Processing of FCP command is deferred */ + if (rc == -EOVERFLOW) { + lpfc_nvmeio_data(phba, + "NVMET RCV BUSY: xri x%x sz %d from %06x\n", + oxid, size, sid); + /* defer reposting rcv buffer till .defer_rcv callback */ + ctxp->rqb_buffer = nvmebuf; + atomic_inc(&tgtp->rcv_fcp_cmd_out); + return; + } + atomic_inc(&tgtp->rcv_fcp_cmd_drop); lpfc_printf_log(phba, KERN_ERR, LOG_NVME_IOERR, "6159 FCP Drop IO x%x: err x%x: x%x x%x x%x\n", diff --git a/drivers/scsi/lpfc/lpfc_nvmet.h b/drivers/scsi/lpfc/lpfc_nvmet.h index e675ef17be08..48a76788b003 100644 --- a/drivers/scsi/lpfc/lpfc_nvmet.h +++ b/drivers/scsi/lpfc/lpfc_nvmet.h @@ -49,6 +49,7 @@ struct lpfc_nvmet_tgtport { atomic_t rcv_fcp_cmd_in; atomic_t rcv_fcp_cmd_out; atomic_t rcv_fcp_cmd_drop; + atomic_t rcv_fcp_cmd_defer; atomic_t xmt_fcp_release; /* Stats counters - lpfc_nvmet_xmt_fcp_op */