diff options
Diffstat (limited to 'drivers/cxl/core')
-rw-r--r-- | drivers/cxl/core/pmem.c | 78 | ||||
-rw-r--r-- | drivers/cxl/core/region.c | 64 |
2 files changed, 128 insertions, 14 deletions
diff --git a/drivers/cxl/core/pmem.c b/drivers/cxl/core/pmem.c index 1d12a8206444..4d36805079ad 100644 --- a/drivers/cxl/core/pmem.c +++ b/drivers/cxl/core/pmem.c @@ -219,7 +219,8 @@ EXPORT_SYMBOL_NS_GPL(to_cxl_nvdimm, CXL); static struct lock_class_key cxl_nvdimm_key; -static struct cxl_nvdimm *cxl_nvdimm_alloc(struct cxl_memdev *cxlmd) +static struct cxl_nvdimm *cxl_nvdimm_alloc(struct cxl_nvdimm_bridge *cxl_nvb, + struct cxl_memdev *cxlmd) { struct cxl_nvdimm *cxl_nvd; struct device *dev; @@ -230,6 +231,7 @@ static struct cxl_nvdimm *cxl_nvdimm_alloc(struct cxl_memdev *cxlmd) dev = &cxl_nvd->dev; cxl_nvd->cxlmd = cxlmd; + cxlmd->cxl_nvd = cxl_nvd; device_initialize(dev); lockdep_set_class(&dev->mutex, &cxl_nvdimm_key); device_set_pm_not_required(dev); @@ -240,27 +242,60 @@ static struct cxl_nvdimm *cxl_nvdimm_alloc(struct cxl_memdev *cxlmd) return cxl_nvd; } -static void cxl_nvd_unregister(void *dev) +static void cxl_nvd_unregister(void *_cxl_nvd) { - device_unregister(dev); + struct cxl_nvdimm *cxl_nvd = _cxl_nvd; + struct cxl_memdev *cxlmd = cxl_nvd->cxlmd; + struct cxl_nvdimm_bridge *cxl_nvb = cxlmd->cxl_nvb; + + /* + * Either the bridge is in ->remove() context under the device_lock(), + * or cxlmd_release_nvdimm() is cancelling the bridge's release action + * for @cxl_nvd and doing it itself (while manually holding the bridge + * lock). + */ + device_lock_assert(&cxl_nvb->dev); + cxl_nvd->cxlmd = NULL; + cxlmd->cxl_nvd = NULL; + device_unregister(&cxl_nvd->dev); +} + +static void cxlmd_release_nvdimm(void *_cxlmd) +{ + struct cxl_memdev *cxlmd = _cxlmd; + struct cxl_nvdimm_bridge *cxl_nvb = cxlmd->cxl_nvb; + + device_lock(&cxl_nvb->dev); + if (cxlmd->cxl_nvd) + devm_release_action(&cxl_nvb->dev, cxl_nvd_unregister, + cxlmd->cxl_nvd); + device_unlock(&cxl_nvb->dev); + put_device(&cxl_nvb->dev); } /** * devm_cxl_add_nvdimm() - add a bridge between a cxl_memdev and an nvdimm - * @host: same host as @cxlmd * @cxlmd: cxl_memdev instance that will perform LIBNVDIMM operations * * Return: 0 on success negative error code on failure. */ -int devm_cxl_add_nvdimm(struct device *host, struct cxl_memdev *cxlmd) +int devm_cxl_add_nvdimm(struct cxl_memdev *cxlmd) { + struct cxl_nvdimm_bridge *cxl_nvb; struct cxl_nvdimm *cxl_nvd; struct device *dev; int rc; - cxl_nvd = cxl_nvdimm_alloc(cxlmd); - if (IS_ERR(cxl_nvd)) - return PTR_ERR(cxl_nvd); + cxl_nvb = cxl_find_nvdimm_bridge(&cxlmd->dev); + if (!cxl_nvb) + return -ENODEV; + + cxl_nvd = cxl_nvdimm_alloc(cxl_nvb, cxlmd); + if (IS_ERR(cxl_nvd)) { + rc = PTR_ERR(cxl_nvd); + goto err_alloc; + } + cxlmd->cxl_nvb = cxl_nvb; dev = &cxl_nvd->dev; rc = dev_set_name(dev, "pmem%d", cxlmd->id); @@ -271,13 +306,34 @@ int devm_cxl_add_nvdimm(struct device *host, struct cxl_memdev *cxlmd) if (rc) goto err; - dev_dbg(host, "%s: register %s\n", dev_name(dev->parent), - dev_name(dev)); + dev_dbg(&cxlmd->dev, "register %s\n", dev_name(dev)); + + /* + * The two actions below arrange for @cxl_nvd to be deleted when either + * the top-level PMEM bridge goes down, or the endpoint device goes + * through ->remove(). + */ + device_lock(&cxl_nvb->dev); + if (cxl_nvb->dev.driver) + rc = devm_add_action_or_reset(&cxl_nvb->dev, cxl_nvd_unregister, + cxl_nvd); + else + rc = -ENXIO; + device_unlock(&cxl_nvb->dev); + + if (rc) + goto err_alloc; - return devm_add_action_or_reset(host, cxl_nvd_unregister, dev); + /* @cxlmd carries a reference on @cxl_nvb until cxlmd_release_nvdimm */ + return devm_add_action_or_reset(&cxlmd->dev, cxlmd_release_nvdimm, cxlmd); err: put_device(dev); +err_alloc: + cxlmd->cxl_nvb = NULL; + cxlmd->cxl_nvd = NULL; + put_device(&cxl_nvb->dev); + return rc; } EXPORT_SYMBOL_NS_GPL(devm_cxl_add_nvdimm, CXL); diff --git a/drivers/cxl/core/region.c b/drivers/cxl/core/region.c index f9ae5ad284ff..1e61d1bafc0c 100644 --- a/drivers/cxl/core/region.c +++ b/drivers/cxl/core/region.c @@ -1812,6 +1812,7 @@ static struct lock_class_key cxl_pmem_region_key; static struct cxl_pmem_region *cxl_pmem_region_alloc(struct cxl_region *cxlr) { struct cxl_region_params *p = &cxlr->params; + struct cxl_nvdimm_bridge *cxl_nvb; struct cxl_pmem_region *cxlr_pmem; struct device *dev; int i; @@ -1839,6 +1840,18 @@ static struct cxl_pmem_region *cxl_pmem_region_alloc(struct cxl_region *cxlr) struct cxl_memdev *cxlmd = cxled_to_memdev(cxled); struct cxl_pmem_region_mapping *m = &cxlr_pmem->mapping[i]; + /* + * Regions never span CXL root devices, so by definition the + * bridge for one device is the same for all. + */ + if (i == 0) { + cxl_nvb = cxl_find_nvdimm_bridge(&cxlmd->dev); + if (!cxl_nvb) { + cxlr_pmem = ERR_PTR(-ENODEV); + goto out; + } + cxlr->cxl_nvb = cxl_nvb; + } m->cxlmd = cxlmd; get_device(&cxlmd->dev); m->start = cxled->dpa_res->start; @@ -1848,6 +1861,7 @@ static struct cxl_pmem_region *cxl_pmem_region_alloc(struct cxl_region *cxlr) dev = &cxlr_pmem->dev; cxlr_pmem->cxlr = cxlr; + cxlr->cxlr_pmem = cxlr_pmem; device_initialize(dev); lockdep_set_class(&dev->mutex, &cxl_pmem_region_key); device_set_pm_not_required(dev); @@ -1860,9 +1874,36 @@ out: return cxlr_pmem; } -static void cxlr_pmem_unregister(void *dev) +static void cxlr_pmem_unregister(void *_cxlr_pmem) { - device_unregister(dev); + struct cxl_pmem_region *cxlr_pmem = _cxlr_pmem; + struct cxl_region *cxlr = cxlr_pmem->cxlr; + struct cxl_nvdimm_bridge *cxl_nvb = cxlr->cxl_nvb; + + /* + * Either the bridge is in ->remove() context under the device_lock(), + * or cxlr_release_nvdimm() is cancelling the bridge's release action + * for @cxlr_pmem and doing it itself (while manually holding the bridge + * lock). + */ + device_lock_assert(&cxl_nvb->dev); + cxlr->cxlr_pmem = NULL; + cxlr_pmem->cxlr = NULL; + device_unregister(&cxlr_pmem->dev); +} + +static void cxlr_release_nvdimm(void *_cxlr) +{ + struct cxl_region *cxlr = _cxlr; + struct cxl_nvdimm_bridge *cxl_nvb = cxlr->cxl_nvb; + + device_lock(&cxl_nvb->dev); + if (cxlr->cxlr_pmem) + devm_release_action(&cxl_nvb->dev, cxlr_pmem_unregister, + cxlr->cxlr_pmem); + device_unlock(&cxl_nvb->dev); + cxlr->cxl_nvb = NULL; + put_device(&cxl_nvb->dev); } /** @@ -1874,12 +1915,14 @@ static void cxlr_pmem_unregister(void *dev) static int devm_cxl_add_pmem_region(struct cxl_region *cxlr) { struct cxl_pmem_region *cxlr_pmem; + struct cxl_nvdimm_bridge *cxl_nvb; struct device *dev; int rc; cxlr_pmem = cxl_pmem_region_alloc(cxlr); if (IS_ERR(cxlr_pmem)) return PTR_ERR(cxlr_pmem); + cxl_nvb = cxlr->cxl_nvb; dev = &cxlr_pmem->dev; rc = dev_set_name(dev, "pmem_region%d", cxlr->id); @@ -1893,10 +1936,25 @@ static int devm_cxl_add_pmem_region(struct cxl_region *cxlr) dev_dbg(&cxlr->dev, "%s: register %s\n", dev_name(dev->parent), dev_name(dev)); - return devm_add_action_or_reset(&cxlr->dev, cxlr_pmem_unregister, dev); + device_lock(&cxl_nvb->dev); + if (cxl_nvb->dev.driver) + rc = devm_add_action_or_reset(&cxl_nvb->dev, + cxlr_pmem_unregister, cxlr_pmem); + else + rc = -ENXIO; + device_unlock(&cxl_nvb->dev); + + if (rc) + goto err_bridge; + + /* @cxlr carries a reference on @cxl_nvb until cxlr_release_nvdimm */ + return devm_add_action_or_reset(&cxlr->dev, cxlr_release_nvdimm, cxlr); err: put_device(dev); +err_bridge: + put_device(&cxl_nvb->dev); + cxlr->cxl_nvb = NULL; return rc; } |