diff --git a/drivers/misc/cxl/api.c b/drivers/misc/cxl/api.c index 103baf0e0c5b..a6543aefa299 100644 --- a/drivers/misc/cxl/api.c +++ b/drivers/misc/cxl/api.c @@ -25,7 +25,6 @@ struct cxl_context *cxl_dev_context_init(struct pci_dev *dev) afu = cxl_pci_to_afu(dev); - get_device(&afu->dev); ctx = cxl_context_alloc(); if (IS_ERR(ctx)) { rc = PTR_ERR(ctx); @@ -61,7 +60,6 @@ err_mapping: err_ctx: kfree(ctx); err_dev: - put_device(&afu->dev); return ERR_PTR(rc); } EXPORT_SYMBOL_GPL(cxl_dev_context_init); @@ -87,8 +85,6 @@ int cxl_release_context(struct cxl_context *ctx) if (ctx->status >= STARTED) return -EBUSY; - put_device(&ctx->afu->dev); - cxl_context_free(ctx); return 0; diff --git a/drivers/misc/cxl/context.c b/drivers/misc/cxl/context.c index 2faa1270d085..6dde7a9d6a7e 100644 --- a/drivers/misc/cxl/context.c +++ b/drivers/misc/cxl/context.c @@ -97,6 +97,12 @@ int cxl_context_init(struct cxl_context *ctx, struct cxl_afu *afu, bool master, ctx->pe = i; ctx->elem = &ctx->afu->spa[i]; ctx->pe_inserted = false; + + /* + * take a ref on the afu so that it stays alive at-least till + * this context is reclaimed inside reclaim_ctx. + */ + cxl_afu_get(afu); return 0; } @@ -278,6 +284,9 @@ static void reclaim_ctx(struct rcu_head *rcu) if (ctx->irq_bitmap) kfree(ctx->irq_bitmap); + /* Drop ref to the afu device taken during cxl_context_init */ + cxl_afu_put(ctx->afu); + kfree(ctx); } diff --git a/drivers/misc/cxl/cxl.h b/drivers/misc/cxl/cxl.h index 0cfb9c129f27..25ae57fa79b0 100644 --- a/drivers/misc/cxl/cxl.h +++ b/drivers/misc/cxl/cxl.h @@ -403,6 +403,18 @@ struct cxl_afu { bool enabled; }; +/* AFU refcount management */ +static inline struct cxl_afu *cxl_afu_get(struct cxl_afu *afu) +{ + + return (get_device(&afu->dev) == NULL) ? NULL : afu; +} + +static inline void cxl_afu_put(struct cxl_afu *afu) +{ + put_device(&afu->dev); +} + struct cxl_irq_name { struct list_head list; diff --git a/drivers/misc/cxl/file.c b/drivers/misc/cxl/file.c index 7ccd2998be92..5cc14599837d 100644 --- a/drivers/misc/cxl/file.c +++ b/drivers/misc/cxl/file.c @@ -67,7 +67,13 @@ static int __afu_open(struct inode *inode, struct file *file, bool master) spin_unlock(&adapter->afu_list_lock); goto err_put_adapter; } - get_device(&afu->dev); + + /* + * taking a ref to the afu so that it doesn't go away + * for rest of the function. This ref is released before + * we return. + */ + cxl_afu_get(afu); spin_unlock(&adapter->afu_list_lock); if (!afu->current_mode) @@ -90,13 +96,12 @@ static int __afu_open(struct inode *inode, struct file *file, bool master) file->private_data = ctx; cxl_ctx_get(); - /* Our ref on the AFU will now hold the adapter */ - put_device(&adapter->dev); - - return 0; + /* indicate success */ + rc = 0; err_put_afu: - put_device(&afu->dev); + /* release the ref taken earlier */ + cxl_afu_put(afu); err_put_adapter: put_device(&adapter->dev); return rc; @@ -131,8 +136,6 @@ int afu_release(struct inode *inode, struct file *file) mutex_unlock(&ctx->mapping_lock); } - put_device(&ctx->afu->dev); - /* * At this this point all bottom halfs have finished and we should be * getting no more IRQs from the hardware for this context. Once it's