5 files changed, 15 insertions, 21 deletions

diff --git a/drivers/misc/cxl/context.c b/drivers/misc/cxl/context.c
index cca4721..4aa31a3 100644
--- a/drivers/misc/cxl/context.c
+++ b/drivers/misc/cxl/context.c
@@ -82,12 +82,12 @@ int cxl_context_init(struct cxl_context *ctx, struct cxl_afu *afu, bool master)
 	 * Allocating IDR! We better make sure everything's setup that
 	 * dereferences from it.
 	 */
+	mutex_lock(&afu->contexts_lock);
 	idr_preload(GFP_KERNEL);
-	spin_lock(&afu->contexts_lock);
 	i = idr_alloc(&ctx->afu->contexts_idr, ctx, 0,
 		      ctx->afu->num_procs, GFP_NOWAIT);
-	spin_unlock(&afu->contexts_lock);
 	idr_preload_end();
+	mutex_unlock(&afu->contexts_lock);
 	if (i < 0)
 		return i;
 
@@ -168,21 +168,22 @@ void cxl_context_detach_all(struct cxl_afu *afu)
 	struct cxl_context *ctx;
 	int tmp;
 
-	rcu_read_lock();
-	idr_for_each_entry(&afu->contexts_idr, ctx, tmp)
+	mutex_lock(&afu->contexts_lock);
+	idr_for_each_entry(&afu->contexts_idr, ctx, tmp) {
 		/*
 		 * Anything done in here needs to be setup before the IDR is
 		 * created and torn down after the IDR removed
 		 */
 		__detach_context(ctx);
-	rcu_read_unlock();
+	}
+	mutex_unlock(&afu->contexts_lock);
 }
 
 void cxl_context_free(struct cxl_context *ctx)
 {
-	spin_lock(&ctx->afu->contexts_lock);
+	mutex_lock(&ctx->afu->contexts_lock);
 	idr_remove(&ctx->afu->contexts_idr, ctx->pe);
-	spin_unlock(&ctx->afu->contexts_lock);
+	mutex_unlock(&ctx->afu->contexts_lock);
 	synchronize_rcu();
 
 	free_page((u64)ctx->sstp);
diff --git a/drivers/misc/cxl/cxl.h b/drivers/misc/cxl/cxl.h
index b5b6bda..7c05239 100644
--- a/drivers/misc/cxl/cxl.h
+++ b/drivers/misc/cxl/cxl.h
@@ -351,7 +351,7 @@ struct cxl_afu {
 	struct device *chardev_s, *chardev_m, *chardev_d;
 	struct idr contexts_idr;
 	struct dentry *debugfs;
-	spinlock_t contexts_lock;
+	struct mutex contexts_lock;
 	struct mutex spa_mutex;
 	spinlock_t afu_cntl_lock;
 
diff --git a/drivers/misc/cxl/native.c b/drivers/misc/cxl/native.c
index 9a5a442..1001cf4 100644
--- a/drivers/misc/cxl/native.c
+++ b/drivers/misc/cxl/native.c
@@ -610,13 +610,6 @@ static inline int detach_process_native_dedicated(struct cxl_context *ctx)
 	return 0;
 }
 
-/*
- * TODO: handle case when this is called inside a rcu_read_lock() which may
- * happen when we unbind the driver (ie. cxl_context_detach_all()) .  Terminate
- * & remove use a mutex lock and schedule which will not good with lock held.
- * May need to write do_process_element_cmd() that handles outstanding page
- * faults synchronously.
- */
 static inline int detach_process_native_afu_directed(struct cxl_context *ctx)
 {
 	if (!ctx->pe_inserted)
diff --git a/drivers/misc/cxl/pci.c b/drivers/misc/cxl/pci.c
index 10c98ab..0f2cc9f8 100644
--- a/drivers/misc/cxl/pci.c
+++ b/drivers/misc/cxl/pci.c
@@ -502,7 +502,7 @@ static struct cxl_afu *cxl_alloc_afu(struct cxl *adapter, int slice)
 	afu->dev.release = cxl_release_afu;
 	afu->slice = slice;
 	idr_init(&afu->contexts_idr);
-	spin_lock_init(&afu->contexts_lock);
+	mutex_init(&afu->contexts_lock);
 	spin_lock_init(&afu->afu_cntl_lock);
 	mutex_init(&afu->spa_mutex);
 
diff --git a/drivers/misc/cxl/sysfs.c b/drivers/misc/cxl/sysfs.c
index ce7ec06..461bdbd 100644
--- a/drivers/misc/cxl/sysfs.c
+++ b/drivers/misc/cxl/sysfs.c
@@ -121,7 +121,7 @@ static ssize_t reset_store_afu(struct device *device,
 	int rc;
 
 	/* Not safe to reset if it is currently in use */
-	spin_lock(&afu->contexts_lock);
+	mutex_lock(&afu->contexts_lock);
 	if (!idr_is_empty(&afu->contexts_idr)) {
 		rc = -EBUSY;
 		goto err;
@@ -132,7 +132,7 @@ static ssize_t reset_store_afu(struct device *device,
 
 	rc = count;
 err:
-	spin_unlock(&afu->contexts_lock);
+	mutex_unlock(&afu->contexts_lock);
 	return rc;
 }
 
@@ -247,7 +247,7 @@ static ssize_t mode_store(struct device *device, struct device_attribute *attr,
 	int rc = -EBUSY;
 
 	/* can't change this if we have a user */
-	spin_lock(&afu->contexts_lock);
+	mutex_lock(&afu->contexts_lock);
 	if (!idr_is_empty(&afu->contexts_idr))
 		goto err;
 
@@ -271,7 +271,7 @@ static ssize_t mode_store(struct device *device, struct device_attribute *attr,
 	afu->current_mode = 0;
 	afu->num_procs = 0;
 
-	spin_unlock(&afu->contexts_lock);
+	mutex_unlock(&afu->contexts_lock);
 
 	if ((rc = _cxl_afu_deactivate_mode(afu, old_mode)))
 		return rc;
@@ -280,7 +280,7 @@ static ssize_t mode_store(struct device *device, struct device_attribute *attr,
 
 	return count;
 err:
-	spin_unlock(&afu->contexts_lock);
+	mutex_unlock(&afu->contexts_lock);
 	return rc;
 }