drm: Remove linked lists for lessees

These are already tracked in the XArray so we do not need to also keep
a doubly-linked list.

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

diff --git a/drivers/gpu/drm/drm_auth.c b/drivers/gpu/drm/drm_auth.c
index c0e9808aa5123776e5cb035baedc08cf7336b442..d44b418c35d3e85e13f0a710dc50fdd8b1f755b4 100644 (file)
--- a/drivers/gpu/drm/drm_auth.c
+++ b/drivers/gpu/drm/drm_auth.c
@@ -113,10 +113,10 @@ struct drm_master *drm_master_create(struct drm_device *dev)
        master->dev = dev;
 
        /* initialize the tree of output resource lessees */
-       INIT_LIST_HEAD(&master->lessees);
-       INIT_LIST_HEAD(&master->lessee_list);
+       master->lessor = NULL;
+       master->lessee_id = 0;
        idr_init(&master->leases);
-       xa_init_flags(&master->lessee_xa, XA_FLAGS_ALLOC1);
+       xa_init_flags(&master->lessees, XA_FLAGS_ALLOC1);
 
        return master;
 }

diff --git a/drivers/gpu/drm/drm_lease.c b/drivers/gpu/drm/drm_lease.c
index 40a342d9e0343b2f927771d928fa2498a5f83460..72e6587e7257faf17e7248166d676269d9aa929b 100644 (file)
--- a/drivers/gpu/drm/drm_lease.c
+++ b/drivers/gpu/drm/drm_lease.c
@@ -16,9 +16,6 @@
 #include "drm_internal.h"
 #include "drm_legacy.h"
 
-#define drm_for_each_lessee(lessee, lessor) \
-       list_for_each_entry((lessee), &(lessor)->lessees, lessee_list)
-
 static uint64_t drm_lease_idr_object;
 
 /**
@@ -50,7 +47,7 @@ static struct drm_master*
 _drm_find_lessee(struct drm_master *master, int lessee_id)
 {
        lockdep_assert_held(&master->dev->mode_config.idr_mutex);
-       return xa_load(&drm_lease_owner(master)->lessee_xa, lessee_id);
+       return xa_load(&drm_lease_owner(master)->lessees, lessee_id);
 }
 
 /**
@@ -86,9 +83,10 @@ static int _drm_lease_held_master(struct drm_master *master, int id)
 static bool _drm_has_leased(struct drm_master *master, int id)
 {
        struct drm_master *lessee;
+       unsigned long index;
 
        lockdep_assert_held(&master->dev->mode_config.idr_mutex);
-       drm_for_each_lessee(lessee, master)
+       xa_for_each(&master->lessees, index, lessee)
                if (_drm_lease_held_master(lessee, id))
                        return true;
        return false;
@@ -225,13 +223,12 @@ static struct drm_master *drm_lease_create(struct drm_master *lessor, struct idr
        }
 
        /* Insert the new lessee into the tree */
-       error = xa_alloc(&drm_lease_owner(lessor)->lessee_xa,
-                       &lessee->lessee_id, lessee, xa_limit_32b, GFP_KERNEL);
+       error = xa_alloc(&drm_lease_owner(lessor)->lessees, &lessee->lessee_id,
+                       lessee, xa_limit_32b, GFP_KERNEL);
        if (error < 0)
                goto out_lessee;
 
        lessee->lessor = drm_master_get(lessor);
-       list_add_tail(&lessee->lessee_list, &lessor->lessees);
 
        /* Move the leases over */
        lessee->leases = *leases;
@@ -265,20 +262,13 @@ void drm_lease_destroy(struct drm_master *master)
 
        DRM_DEBUG_LEASE("drm_lease_destroy %d\n", master->lessee_id);
 
-       /* This master is referenced by all lessees, hence it cannot be destroyed
-        * until all of them have been
-        */
-       WARN_ON(!list_empty(&master->lessees));
+       WARN_ON(!xa_empty(&master->lessees));
 
        /* Remove this master from the lessee array in the owner */
        if (master->lessee_id != 0) {
                DRM_DEBUG_LEASE("remove master %d from device list of lessees\n", master->lessee_id);
-               xa_erase(&drm_lease_owner(master)->lessee_xa, master->lessee_id);
+               xa_erase(&drm_lease_owner(master)->lessees, master->lessee_id);
        }
-
-       /* Remove this master from any lessee list it may be on */
-       list_del(&master->lessee_list);
-
        mutex_unlock(&dev->mode_config.idr_mutex);
 
        if (master->lessor) {
@@ -307,27 +297,34 @@ static void _drm_lease_revoke(struct drm_master *top)
         * the tree is fully connected, we can do this without recursing
         */
        for (;;) {
+               struct drm_master *tmp;
+               unsigned long index = 0;
+
                DRM_DEBUG_LEASE("revoke leases for %p %d\n", master, master->lessee_id);
 
                /* Evacuate the lease */
                idr_for_each_entry(&master->leases, entry, object)
                        idr_remove(&master->leases, object);
 
-               /* Depth-first list walk */
+               /* Depth-first tree walk */
+               tmp = xa_find(&master->lessees, &index, ULONG_MAX, XA_PRESENT);
 
                /* Down */
-               if (!list_empty(&master->lessees)) {
-                       master = list_first_entry(&master->lessees, struct drm_master, lessee_list);
-               } else {
-                       /* Up */
-                       while (master != top && master == list_last_entry(&master->lessor->lessees, struct drm_master, lessee_list))
-                               master = master->lessor;
-
-                       if (master == top)
+               if (tmp) {
+                       master = tmp;
+                       continue;
+               }
+               /* Over */
+               while (master != top) {
+                       index = master->lessee_id;
+                       tmp = xa_find_after(&master->lessor->lessees, &index,
+                                       ULONG_MAX, XA_PRESENT);
+                       if (tmp) {
+                               master = tmp;
                                break;
-
-                       /* Over */
-                       master = list_next_entry(master, lessee_list);
+                       }
+                       /* Up */
+                       master = master->lessor;
                }
        }
 }
@@ -602,6 +599,7 @@ int drm_mode_list_lessees_ioctl(struct drm_device *dev,
        __u32 __user *lessee_ids = (__u32 __user *) (uintptr_t) (arg->lessees_ptr);
        __u32 count_lessees = arg->count_lessees;
        struct drm_master *lessor = lessor_priv->master, *lessee;
+       unsigned long index;
        int count;
        int ret = 0;
 
@@ -617,7 +615,7 @@ int drm_mode_list_lessees_ioctl(struct drm_device *dev,
        mutex_lock(&dev->mode_config.idr_mutex);
 
        count = 0;
-       drm_for_each_lessee(lessee, lessor) {
+       xa_for_each(&lessor->lessees, index, lessee) {
                /* Only list un-revoked leases */
                if (!idr_is_empty(&lessee->leases)) {
                        if (count_lessees > count) {

diff --git a/include/drm/drm_auth.h b/include/drm/drm_auth.h
index 735ea2839236ee7e89a88f1e2917c70923e0f882..c16b2c3ab461f4aa9a6008b424373cca33d44078 100644 (file)
--- a/include/drm/drm_auth.h
+++ b/include/drm/drm_auth.h
@@ -95,10 +95,8 @@ struct drm_master {
 
        struct drm_master *lessor;
        int     lessee_id;
-       struct list_head lessee_list;
-       struct list_head lessees;
        struct idr leases;
-       struct xarray lessee_xa;
+       struct xarray lessees;
        /* private: */
 #if IS_ENABLED(CONFIG_DRM_LEGACY)
        struct drm_lock_data lock;