linux-kernel - [PATCH v2 4/6] drm: Convert magic

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20250821145429.305526-5-sidhartha.kumar@oracle.com>
Date: Thu, 21 Aug 2025 14:54:27 +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 v2 4/6] drm: Convert magic_map 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 | 18 ++++++++----------
 include/drm/drm_auth.h     |  5 ++---
 2 files changed, 10 insertions(+), 13 deletions(-)

diff --git a/drivers/gpu/drm/drm_auth.c b/drivers/gpu/drm/drm_auth.c
index a2556d16bed6..66a672384367 100644
--- a/drivers/gpu/drm/drm_auth.c
+++ b/drivers/gpu/drm/drm_auth.c
@@ -98,16 +98,15 @@ int drm_getmagic(struct drm_device *dev, void *data, struct drm_file *file_priv)
 
 	guard(mutex)(&dev->master_mutex);
 	if (!file_priv->magic) {
-		ret = idr_alloc(&file_priv->master->magic_map, file_priv,
-				1, 0, GFP_KERNEL);
-		if (ret >= 0)
-			file_priv->magic = ret;
+		ret = xa_alloc(&file_priv->master->magic_map,
+				&file_priv->magic, file_priv,
+				xa_limit_31b, GFP_KERNEL);
 	}
 	auth->magic = file_priv->magic;
 
 	drm_dbg_core(dev, "%u\n", auth->magic);
 
-	return ret < 0 ? ret : 0;
+	return ret;
 }
 
 int drm_authmagic(struct drm_device *dev, void *data,
@@ -119,10 +118,10 @@ int drm_authmagic(struct drm_device *dev, void *data,
 	drm_dbg_core(dev, "%u\n", auth->magic);
 
 	guard(mutex)(&dev->master_mutex);
-	file = idr_find(&file_priv->master->magic_map, auth->magic);
+	file = xa_load(&file_priv->master->magic_map, auth->magic);
 	if (file) {
 		file->authenticated = 1;
-		idr_replace(&file_priv->master->magic_map, NULL, auth->magic);
+		xa_store(&file_priv->master->magic_map, auth->magic, NULL, 0);
 	}
 
 	return file ? 0 : -EINVAL;
@@ -137,7 +136,7 @@ struct drm_master *drm_master_create(struct drm_device *dev)
 		return NULL;
 
 	kref_init(&master->refcount);
-	idr_init_base(&master->magic_map, 1);
+	xa_init_flags(&master->magic_map, XA_FLAGS_ALLOC1);
 	master->dev = dev;
 
 	/* initialize the tree of output resource lessees */
@@ -342,7 +341,7 @@ void drm_master_release(struct drm_file *file_priv)
 	guard(mutex)(&dev->master_mutex);
 	master = file_priv->master;
 	if (file_priv->magic)
-		idr_remove(&file_priv->master->magic_map, file_priv->magic);
+		xa_erase(&file_priv->master->magic_map, file_priv->magic);
 
 	if (!drm_is_current_master_locked(file_priv))
 		goto out;
@@ -408,7 +407,6 @@ static void drm_master_destroy(struct kref *kref)
 	if (drm_core_check_feature(dev, DRIVER_MODESET))
 		drm_lease_destroy(master);
 
-	idr_destroy(&master->magic_map);
 	idr_destroy(&master->leases);
 	idr_destroy(&master->lessee_idr);
 
diff --git a/include/drm/drm_auth.h b/include/drm/drm_auth.h
index 50131383ed81..3026aedbc205 100644
--- a/include/drm/drm_auth.h
+++ b/include/drm/drm_auth.h
@@ -58,10 +58,9 @@ struct drm_master {
 	 */
 	int unique_len;
 	/**
-	 * @magic_map: Map of used authentication tokens. Protected by
-	 * &drm_device.master_mutex.
+	 * @magic_map: Map of used authentication tokens.
 	 */
-	struct idr magic_map;
+	struct xarray magic_map;
 	void *driver_priv;
 
 	/**
-- 
2.43.0