linux-kernel - [PATCH 5/6] drm: Convert lessee

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Message-ID: <20250818190046.157962-6-sidhartha.kumar@oracle.com>
Date: Mon, 18 Aug 2025 19:00:45 +0000
From: Sidhartha Kumar <sidhartha.kumar@...cle.com>
To: linux-kernel@...r.kernel.org, dri-devel@...ts.freedesktop.org
Cc: maarten.lankhorst@...ux.intel.com, mripard@...nel.org, tzimmermann@...e.de,
        airlied@...il.com, simona@...ll.ch, willy@...radead.org,
        sidhartha.kumar@...cle.com
Subject: [PATCH 5/6] drm: Convert lessee_idr to XArray

From: Matthew Wilcox <willy@...radead.org>

Part of the mass conversion of IDR users to the XArray API.

Signed-off-by: Matthew Wilcox <willy@...radead.org>
Signed-off-by: Sidhartha Kumar <sidhartha.kumar@...cle.com>
---
 drivers/gpu/drm/drm_auth.c  |  4 +---
 drivers/gpu/drm/drm_lease.c | 15 ++++++---------
 include/drm/drm_auth.h      |  4 ++--
 3 files changed, 9 insertions(+), 14 deletions(-)

diff --git a/drivers/gpu/drm/drm_auth.c b/drivers/gpu/drm/drm_auth.c
index 41aa20144a9d..ca94d148b889 100644
--- a/drivers/gpu/drm/drm_auth.c
+++ b/drivers/gpu/drm/drm_auth.c
@@ -143,8 +143,7 @@ struct drm_master *drm_master_create(struct drm_device *dev)
 	/* initialize the tree of output resource lessees */
 	INIT_LIST_HEAD(&master->lessees);
 	INIT_LIST_HEAD(&master->lessee_list);
-	idr_init(&master->leases);
-	idr_init_base(&master->lessee_idr, 1);
+	xa_init_flags(&master->lessee_xa, XA_FLAGS_ALLOC1);
 
 	return master;
 }
@@ -425,7 +424,6 @@ static void drm_master_destroy(struct kref *kref)
 		drm_lease_destroy(master);
 
 	idr_destroy(&master->leases);
-	idr_destroy(&master->lessee_idr);
 
 	kfree(master->unique);
 	kfree(master);
diff --git a/drivers/gpu/drm/drm_lease.c b/drivers/gpu/drm/drm_lease.c
index 94375c6a5425..a9d5b8a48b24 100644
--- a/drivers/gpu/drm/drm_lease.c
+++ b/drivers/gpu/drm/drm_lease.c
@@ -82,7 +82,7 @@ static struct drm_master*
 _drm_find_lessee(struct drm_master *master, int lessee_id)
 {
 	lockdep_assert_held(&master->dev->mode_config.idr_mutex);
-	return idr_find(&drm_lease_owner(master)->lessee_idr, lessee_id);
+	return xa_load(&drm_lease_owner(master)->lessee_xa, lessee_id);
 }
 
 static int _drm_lease_held_master(struct drm_master *master, int id)
@@ -210,7 +210,6 @@ static struct drm_master *drm_lease_create(struct drm_master *lessor, struct idr
 	int error;
 	struct drm_master *lessee;
 	int object;
-	int id;
 	void *entry;
 
 	drm_dbg_lease(dev, "lessor %d\n", lessor->lessee_id);
@@ -237,13 +236,11 @@ static struct drm_master *drm_lease_create(struct drm_master *lessor, struct idr
 	}
 
 	/* Insert the new lessee into the tree */
-	id = idr_alloc(&(drm_lease_owner(lessor)->lessee_idr), lessee, 1, 0, GFP_KERNEL);
-	if (id < 0) {
-		error = id;
+	error = xa_alloc(&drm_lease_owner(lessor)->lessee_xa,
+			&lessee->lessee_id, lessee, xa_limit_32b, GFP_KERNEL);
+	if (error < 0)
 		goto out_lessee;
-	}
 
-	lessee->lessee_id = id;
 	lessee->lessor = drm_master_get(lessor);
 	list_add_tail(&lessee->lessee_list, &lessor->lessees);
 
@@ -276,11 +273,11 @@ void drm_lease_destroy(struct drm_master *master)
 	 */
 	WARN_ON(!list_empty(&master->lessees));
 
-	/* Remove this master from the lessee idr in the owner */
+	/* Remove this master from the lessee array in the owner */
 	if (master->lessee_id != 0) {
 		drm_dbg_lease(dev, "remove master %d from device list of lessees\n",
 			      master->lessee_id);
-		idr_remove(&(drm_lease_owner(master)->lessee_idr), master->lessee_id);
+		xa_erase(&drm_lease_owner(master)->lessee_xa, master->lessee_id);
 	}
 
 	/* Remove this master from any lessee list it may be on */
diff --git a/include/drm/drm_auth.h b/include/drm/drm_auth.h
index 3026aedbc205..1b6064afc8b0 100644
--- a/include/drm/drm_auth.h
+++ b/include/drm/drm_auth.h
@@ -120,12 +120,12 @@ struct drm_master {
 	struct idr leases;
 
 	/**
-	 * @lessee_idr:
+	 * @lessee_xa:
 	 *
 	 * All lessees under this owner (only used where @lessor is NULL).
 	 * Protected by &drm_device.mode_config's &drm_mode_config.idr_mutex.
 	 */
-	struct idr lessee_idr;
+	struct xarray lessee_xa;
 };
 
 struct drm_master *drm_master_get(struct drm_master *master);
-- 
2.43.0