From: Matthew Wilcox <willy@infradead.org>
Date: Fri, 15 Mar 2019 12:15:52 +0000 (-0400)
Subject: habanalabs: Convert cb_handles to XArray
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=942f9437a3b9a8ffc6ec28d56962b2447bb1b14c;p=users%2Fwilly%2Fxarray.git

habanalabs: Convert cb_handles to XArray

Signed-off-by: Matthew Wilcox <willy@infradead.org>
---

diff --git a/drivers/misc/habanalabs/command_buffer.c b/drivers/misc/habanalabs/command_buffer.c
index e495f44064fa..5bceeddbf466 100644
--- a/drivers/misc/habanalabs/command_buffer.c
+++ b/drivers/misc/habanalabs/command_buffer.c
@@ -144,22 +144,17 @@ int hl_cb_create(struct hl_device *hdev, struct hl_cb_mgr *mgr,
 	cb->hdev = hdev;
 	cb->ctx_id = ctx_id;
 
-	spin_lock(&mgr->cb_lock);
-	rc = idr_alloc(&mgr->cb_handles, cb, 1, 0, GFP_ATOMIC);
-	spin_unlock(&mgr->cb_lock);
-
+	rc = xa_alloc(&mgr->cb_handles, &cb->id, cb, xa_limit_31b, GFP_KERNEL);
 	if (rc < 0) {
-		dev_err(hdev->dev, "Failed to allocate IDR for a new CB\n");
+		dev_err(hdev->dev, "Failed to allocate ID for a new CB\n");
 		goto release_cb;
 	}
 
-	cb->id = rc;
-
 	kref_init(&cb->refcount);
 	spin_lock_init(&cb->lock);
 
 	/*
-	 * idr is 32-bit so we can safely OR it with a mask that is above
+	 * id is 32-bit so we can safely OR it with a mask that is above
 	 * 32 bit
 	 */
 	*handle = cb->id | HL_MMAP_CB_MASK;
@@ -183,22 +178,14 @@ int hl_cb_destroy(struct hl_device *hdev, struct hl_cb_mgr *mgr, u64 cb_handle)
 	u32 handle;
 	int rc = 0;
 
-	/*
-	 * handle was given to user to do mmap, I need to shift it back to
-	 * how the idr module gave it to me
-	 */
+	/* convert the handle back to an ID */
 	cb_handle >>= PAGE_SHIFT;
 	handle = (u32) cb_handle;
 
-	spin_lock(&mgr->cb_lock);
-
-	cb = idr_find(&mgr->cb_handles, handle);
+	cb = xa_erase(&mgr->cb_handles, handle);
 	if (cb) {
-		idr_remove(&mgr->cb_handles, handle);
-		spin_unlock(&mgr->cb_lock);
 		kref_put(&cb->refcount, cb_release);
 	} else {
-		spin_unlock(&mgr->cb_lock);
 		dev_err(hdev->dev,
 			"CB destroy failed, no match to handle 0x%x\n", handle);
 		rc = -EINVAL;
@@ -341,11 +328,11 @@ struct hl_cb *hl_cb_get(struct hl_device *hdev, struct hl_cb_mgr *mgr,
 {
 	struct hl_cb *cb;
 
-	spin_lock(&mgr->cb_lock);
-	cb = idr_find(&mgr->cb_handles, handle);
+	xa_lock(&mgr->cb_handles);
+	cb = xa_load(&mgr->cb_handles, handle);
 
 	if (!cb) {
-		spin_unlock(&mgr->cb_lock);
+		xa_unlock(&mgr->cb_handles);
 		dev_warn(hdev->dev,
 			"CB get failed, no match to handle %d\n", handle);
 		return NULL;
@@ -353,7 +340,7 @@ struct hl_cb *hl_cb_get(struct hl_device *hdev, struct hl_cb_mgr *mgr,
 
 	kref_get(&cb->refcount);
 
-	spin_unlock(&mgr->cb_lock);
+	xa_unlock(&mgr->cb_handles);
 
 	return cb;
 
@@ -366,26 +353,20 @@ void hl_cb_put(struct hl_cb *cb)
 
 void hl_cb_mgr_init(struct hl_cb_mgr *mgr)
 {
-	spin_lock_init(&mgr->cb_lock);
-	idr_init(&mgr->cb_handles);
+	xa_init_flags(&mgr->cb_handles, XA_FLAGS_ALLOC1);
 }
 
 void hl_cb_mgr_fini(struct hl_device *hdev, struct hl_cb_mgr *mgr)
 {
 	struct hl_cb *cb;
-	struct idr *idp;
-	u32 id;
-
-	idp = &mgr->cb_handles;
+	unsigned long id;
 
-	idr_for_each_entry(idp, cb, id) {
+	xa_for_each(&mgr->cb_handles, id, cb) {
 		if (kref_put(&cb->refcount, cb_release) != 1)
 			dev_err(hdev->dev,
-				"CB %d for CTX ID %d is still alive\n",
+				"CB %ld for CTX ID %d is still alive\n",
 				id, cb->ctx_id);
 	}
-
-	idr_destroy(&mgr->cb_handles);
 }
 
 struct hl_cb *hl_cb_kernel_create(struct hl_device *hdev, u32 cb_size)
diff --git a/drivers/misc/habanalabs/habanalabs.h b/drivers/misc/habanalabs/habanalabs.h
index 10da9940ee0d..399093ee50cd 100644
--- a/drivers/misc/habanalabs/habanalabs.h
+++ b/drivers/misc/habanalabs/habanalabs.h
@@ -236,12 +236,10 @@ struct hl_dma_fence {
 
 /**
  * struct hl_cb_mgr - describes a Command Buffer Manager.
- * @cb_lock: protects cb_handles.
- * @cb_handles: an idr to hold all command buffer handles.
+ * @cb_handles: an XArray to hold all command buffer handles.
  */
 struct hl_cb_mgr {
-	spinlock_t		cb_lock;
-	struct idr		cb_handles; /* protected by cb_lock */
+	struct xarray		cb_handles;
 };
 
 /**