diff options
Diffstat (limited to 'usr/src')
| -rw-r--r-- | usr/src/uts/common/io/nvme/nvme.c | 47 |
1 files changed, 36 insertions, 11 deletions
diff --git a/usr/src/uts/common/io/nvme/nvme.c b/usr/src/uts/common/io/nvme/nvme.c index 0edb37f16e..68d6855803 100644 --- a/usr/src/uts/common/io/nvme/nvme.c +++ b/usr/src/uts/common/io/nvme/nvme.c @@ -72,6 +72,14 @@ * as the configured queue length. * * + * Polled I/O Support: + * + * For kernel core dump support the driver can do polled I/O. As interrupts are + * turned off while dumping the driver will just submit a command in the regular + * way, and then repeatedly attempt a command retrieval until it gets the + * command back. + * + * * Namespace Support: * * NVMe devices can have multiple namespaces, each being a independent data @@ -176,7 +184,6 @@ * * TODO: * - figure out sane default for I/O queue depth reported to blkdev - * - polled I/O support to support kernel core dumping * - FMA handling of media errors * - support for devices supporting very large I/O requests using chained PRPs * - support for configuring hardware parameters like interrupt coalescing @@ -856,20 +863,21 @@ nvme_retrieve_cmd(nvme_t *nvme, nvme_qpair_t *qp) (void) ddi_dma_sync(qp->nq_cqdma->nd_dmah, 0, sizeof (nvme_cqe_t) * qp->nq_nentry, DDI_DMA_SYNC_FORKERNEL); + mutex_enter(&qp->nq_mutex); cqe = &qp->nq_cq[qp->nq_cqhead]; /* Check phase tag of CQE. Hardware inverts it for new entries. */ - if (cqe->cqe_sf.sf_p == qp->nq_phase) + if (cqe->cqe_sf.sf_p == qp->nq_phase) { + mutex_exit(&qp->nq_mutex); return (NULL); + } ASSERT(nvme->n_ioq[cqe->cqe_sqid] == qp); ASSERT(cqe->cqe_cid < qp->nq_nentry); - mutex_enter(&qp->nq_mutex); cmd = qp->nq_cmd[cqe->cqe_cid]; qp->nq_cmd[cqe->cqe_cid] = NULL; qp->nq_active_cmds--; - mutex_exit(&qp->nq_mutex); ASSERT(cmd != NULL); ASSERT(cmd->nc_nvme == nvme); @@ -886,6 +894,7 @@ nvme_retrieve_cmd(nvme_t *nvme, nvme_qpair_t *qp) qp->nq_phase = qp->nq_phase ? 0 : 1; nvme_put32(cmd->nc_nvme, qp->nq_cqhdbl, head.r); + mutex_exit(&qp->nq_mutex); return (cmd); } @@ -3269,26 +3278,42 @@ static int nvme_bd_cmd(nvme_namespace_t *ns, bd_xfer_t *xfer, uint8_t opc) { nvme_t *nvme = ns->ns_nvme; - nvme_cmd_t *cmd; + nvme_cmd_t *cmd, *ret; + nvme_qpair_t *ioq; + boolean_t poll; if (nvme->n_dead) return (EIO); - /* No polling for now */ - if (xfer->x_flags & BD_XFER_POLL) - return (EIO); - cmd = nvme_create_nvm_cmd(ns, opc, xfer); if (cmd == NULL) return (ENOMEM); cmd->nc_sqid = (CPU->cpu_id % nvme->n_ioq_count) + 1; ASSERT(cmd->nc_sqid <= nvme->n_ioq_count); + ioq = nvme->n_ioq[cmd->nc_sqid]; - if (nvme_submit_cmd(nvme->n_ioq[cmd->nc_sqid], cmd) - != DDI_SUCCESS) + /* + * Get the polling flag before submitting the command. The command may + * complete immediately after it was submitted, which means we must + * treat both cmd and xfer as if they have been freed already. + */ + poll = (xfer->x_flags & BD_XFER_POLL) != 0; + + if (nvme_submit_cmd(ioq, cmd) != DDI_SUCCESS) return (EAGAIN); + if (!poll) + return (0); + + do { + ret = nvme_retrieve_cmd(nvme, ioq); + if (ret != NULL) + nvme_bd_xfer_done(ret); + else + drv_usecwait(10); + } while (ioq->nq_active_cmds != 0); + return (0); } |