From 7ae0fa439faff000744b234d04cb470bfd83593b Mon Sep 17 00:00:00 2001 From: Dan Williams Date: Fri, 19 Feb 2016 12:16:34 -0800 Subject: [PATCH] nfit, libnvdimm: async region scrub workqueue Introduce a workqueue that will be used to run address range scrub asynchronously with the rest of nvdimm device probing. Userspace still wants notification when probing operations complete, so introduce a new callback to flush this workqueue when userspace is awaiting probe completion. Signed-off-by: Dan Williams --- drivers/acpi/nfit.c | 49 +++++++++++++++++++++++++++++++++++++++ drivers/acpi/nfit.h | 3 +++ drivers/nvdimm/core.c | 9 +++++++ include/linux/libnvdimm.h | 1 + 4 files changed, 62 insertions(+) diff --git a/drivers/acpi/nfit.c b/drivers/acpi/nfit.c index 76c9444c9c60..4aa2bd54fc1d 100644 --- a/drivers/acpi/nfit.c +++ b/drivers/acpi/nfit.c @@ -34,6 +34,8 @@ static bool force_enable_dimms; module_param(force_enable_dimms, bool, S_IRUGO|S_IWUSR); MODULE_PARM_DESC(force_enable_dimms, "Ignore _STA (ACPI DIMM device) status"); +static struct workqueue_struct *nfit_wq; + struct nfit_table_prev { struct list_head spas; struct list_head memdevs; @@ -1961,6 +1963,39 @@ int acpi_nfit_init(struct acpi_nfit_desc *acpi_desc, acpi_size sz) } EXPORT_SYMBOL_GPL(acpi_nfit_init); +struct acpi_nfit_flush_work { + struct work_struct work; + struct completion cmp; +}; + +static void flush_probe(struct work_struct *work) +{ + struct acpi_nfit_flush_work *flush; + + flush = container_of(work, typeof(*flush), work); + complete(&flush->cmp); +} + +static int acpi_nfit_flush_probe(struct nvdimm_bus_descriptor *nd_desc) +{ + struct acpi_nfit_desc *acpi_desc = to_acpi_nfit_desc(nd_desc); + struct device *dev = acpi_desc->dev; + struct acpi_nfit_flush_work flush; + + /* bounce the device lock to flush acpi_nfit_add / acpi_nfit_notify */ + device_lock(dev); + device_unlock(dev); + + /* + * Scrub work could take 10s of seconds, userspace may give up so we + * need to be interruptible while waiting. + */ + INIT_WORK_ONSTACK(&flush.work, flush_probe); + COMPLETION_INITIALIZER_ONSTACK(flush.cmp); + queue_work(nfit_wq, &flush.work); + return wait_for_completion_interruptible(&flush.cmp); +} + void acpi_nfit_desc_init(struct acpi_nfit_desc *acpi_desc, struct device *dev) { struct nvdimm_bus_descriptor *nd_desc; @@ -1971,6 +2006,7 @@ void acpi_nfit_desc_init(struct acpi_nfit_desc *acpi_desc, struct device *dev) nd_desc = &acpi_desc->nd_desc; nd_desc->provider_name = "ACPI.NFIT"; nd_desc->ndctl = acpi_nfit_ctl; + nd_desc->flush_probe = acpi_nfit_flush_probe; nd_desc->attr_groups = acpi_nfit_attribute_groups; INIT_LIST_HEAD(&acpi_desc->spa_maps); @@ -2048,6 +2084,8 @@ static int acpi_nfit_remove(struct acpi_device *adev) { struct acpi_nfit_desc *acpi_desc = dev_get_drvdata(&adev->dev); + acpi_desc->cancel = 1; + flush_workqueue(nfit_wq); nvdimm_bus_unregister(acpi_desc->nvdimm_bus); return 0; } @@ -2079,6 +2117,12 @@ static void acpi_nfit_notify(struct acpi_device *adev, u32 event) acpi_desc->nvdimm_bus = nvdimm_bus_register(dev, &acpi_desc->nd_desc); if (!acpi_desc->nvdimm_bus) goto out_unlock; + } else { + /* + * Finish previous registration before considering new + * regions. + */ + flush_workqueue(nfit_wq); } /* Evaluate _FIT */ @@ -2146,12 +2190,17 @@ static __init int nfit_init(void) acpi_str_to_uuid(UUID_NFIT_BUS, nfit_uuid[NFIT_DEV_BUS]); acpi_str_to_uuid(UUID_NFIT_DIMM, nfit_uuid[NFIT_DEV_DIMM]); + nfit_wq = create_singlethread_workqueue("nfit"); + if (!nfit_wq) + return -ENOMEM; + return acpi_bus_register_driver(&acpi_nfit_driver); } static __exit void nfit_exit(void) { acpi_bus_unregister_driver(&acpi_nfit_driver); + destroy_workqueue(nfit_wq); } module_init(nfit_init); diff --git a/drivers/acpi/nfit.h b/drivers/acpi/nfit.h index 524dec0a3adb..e8388fee4cc6 100644 --- a/drivers/acpi/nfit.h +++ b/drivers/acpi/nfit.h @@ -14,6 +14,7 @@ */ #ifndef __NFIT_H__ #define __NFIT_H__ +#include #include #include #include @@ -123,6 +124,8 @@ struct acpi_nfit_desc { struct list_head idts; struct nvdimm_bus *nvdimm_bus; struct device *dev; + struct work_struct work; + unsigned int cancel:1; unsigned long dimm_dsm_force_en; unsigned long bus_dsm_force_en; int (*blk_do_io)(struct nd_blk_region *ndbr, resource_size_t dpa, diff --git a/drivers/nvdimm/core.c b/drivers/nvdimm/core.c index f309e6bf6833..79646d0c3277 100644 --- a/drivers/nvdimm/core.c +++ b/drivers/nvdimm/core.c @@ -298,6 +298,15 @@ static int flush_regions_dimms(struct device *dev, void *data) static ssize_t wait_probe_show(struct device *dev, struct device_attribute *attr, char *buf) { + struct nvdimm_bus *nvdimm_bus = to_nvdimm_bus(dev); + struct nvdimm_bus_descriptor *nd_desc = nvdimm_bus->nd_desc; + int rc; + + if (nd_desc->flush_probe) { + rc = nd_desc->flush_probe(nd_desc); + if (rc) + return rc; + } nd_synchronize(); device_for_each_child(dev, NULL, flush_regions_dimms); return sprintf(buf, "1\n"); diff --git a/include/linux/libnvdimm.h b/include/linux/libnvdimm.h index f398953270d1..2299f8742f7f 100644 --- a/include/linux/libnvdimm.h +++ b/include/linux/libnvdimm.h @@ -71,6 +71,7 @@ struct nvdimm_bus_descriptor { unsigned long dsm_mask; char *provider_name; ndctl_fn ndctl; + int (*flush_probe)(struct nvdimm_bus_descriptor *nd_desc); }; struct nd_cmd_desc { -- 2.20.1