From mboxrd@z Thu Jan 1 00:00:00 1970 From: hch@lst.de (Christoph Hellwig) Date: Fri, 20 Nov 2015 17:35:27 +0100 Subject: [PATCH 32/47] NVMe: Implement namespace list scanning In-Reply-To: <1448037342-18384-1-git-send-email-hch@lst.de> References: <1448037342-18384-1-git-send-email-hch@lst.de> Message-ID: <1448037342-18384-33-git-send-email-hch@lst.de> From: Keith Busch The NVMe 1.1 specification provides an identify mode to return a list of active namespaces. This is more efficient to discover which namespace identifiers are active on a controller, providing potentially significant improvement in scan time for controllers with sparesly populated namespaces. Signed-off-by: Keith Busch --- drivers/nvme/host/core.c | 79 ++++++++++++++++++++++++++++++++++++++++++------ 1 file changed, 70 insertions(+), 9 deletions(-) diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c index 655295f..38d2ecc 100644 --- a/drivers/nvme/host/core.c +++ b/drivers/nvme/host/core.c @@ -255,6 +255,16 @@ int nvme_identify_ctrl(struct nvme_ctrl *dev, struct nvme_id_ctrl **id) return error; } +static int nvme_identify_ns_list(struct nvme_ctrl *dev, unsigned nsid, __le32 *ns_list) +{ + struct nvme_command c = { }; + + c.identify.opcode = nvme_admin_identify; + c.identify.cns = cpu_to_le32(2); + c.identify.nsid = cpu_to_le32(nsid); + return nvme_submit_sync_cmd(dev->admin_q, &c, ns_list, 0x1000); +} + int nvme_identify_ns(struct nvme_ctrl *dev, unsigned nsid, struct nvme_id_ns **id) { @@ -950,33 +960,84 @@ static void nvme_ns_remove(struct nvme_ns *ns) nvme_put_ns(ns); } +static void nvme_validate_ns(struct nvme_ctrl *ctrl, unsigned nsid) +{ + struct nvme_ns *ns; + + ns = nvme_find_ns(ctrl, nsid); + if (ns) { + if (revalidate_disk(ns->disk)) + nvme_ns_remove(ns); + } else + nvme_alloc_ns(ctrl, nsid); +} + +static int nvme_scan_ns_list(struct nvme_ctrl *ctrl, unsigned nn) +{ + struct nvme_ns *ns; + __le32 *ns_list; + unsigned i, j, nsid, prev = 0, num_lists = DIV_ROUND_UP(nn, 1024); + int ret = 0; + + ns_list = kzalloc(0x1000, GFP_KERNEL); + if (!ns_list) + return -ENOMEM; + + for (i = 0; i < num_lists; i++) { + ret = nvme_identify_ns_list(ctrl, prev, ns_list); + if (ret) + goto out; + + for (j = 0; j < min(nn, 1024U); j++) { + nsid = le32_to_cpu(ns_list[j]); + if (!nsid) + goto out; + + nvme_validate_ns(ctrl, nsid); + + while (++prev < nsid) { + ns = nvme_find_ns(ctrl, prev); + if (ns) + nvme_ns_remove(ns); + } + } + nn -= j; + } + out: + kfree(ns_list); + return ret; +} + static void __nvme_scan_namespaces(struct nvme_ctrl *ctrl, unsigned nn) { struct nvme_ns *ns, *next; unsigned i; - for (i = 1; i <= nn; i++) { - ns = nvme_find_ns(ctrl, i); - if (ns) { - if (revalidate_disk(ns->disk)) - nvme_ns_remove(ns); - } else - nvme_alloc_ns(ctrl, i); - } + for (i = 1; i <= nn; i++) + nvme_validate_ns(ctrl, i); + list_for_each_entry_safe(ns, next, &ctrl->namespaces, list) { if (ns->ns_id > nn) nvme_ns_remove(ns); } - list_sort(NULL, &ctrl->namespaces, ns_cmp); } void nvme_scan_namespaces(struct nvme_ctrl *ctrl) { struct nvme_id_ctrl *id; + unsigned nn; if (nvme_identify_ctrl(ctrl, &id)) return; + + nn = le32_to_cpu(id->nn); + if (ctrl->vs >= NVME_VS(1, 1)) { + if (!nvme_scan_ns_list(ctrl, nn)) + goto done; + } __nvme_scan_namespaces(ctrl, le32_to_cpup(&id->nn)); + done: + list_sort(NULL, &ctrl->namespaces, ns_cmp); kfree(id); } -- 1.9.1