[PATCH 17/26] drm/vmwgfx: Convert to new IDA API

[Matthew Wilcox]

Reorder allocation to avoid an awkward lock/unlock/lock sequence.
Simpler code due to being able to use ida_alloc_max(), even if we can't
eliminate the driver's spinlock.

Signed-off-by: Matthew Wilcox <wi...@infradead.org>
---
 drivers/gpu/drm/vmwgfx/vmwgfx_gmrid_manager.c | 41 ++++++-------------
 1 file changed, 12 insertions(+), 29 deletions(-)

diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_gmrid_manager.c 
b/drivers/gpu/drm/vmwgfx/vmwgfx_gmrid_manager.c
index f2f9d88131f2..2d6291373efb 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_gmrid_manager.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_gmrid_manager.c
@@ -51,51 +51,34 @@ static int vmw_gmrid_man_get_node(struct 
ttm_mem_type_manager *man,
 {
        struct vmwgfx_gmrid_man *gman =
                (struct vmwgfx_gmrid_man *)man->priv;
-       int ret = 0;
        int id;
 
        mem->mm_node = NULL;
 
+       id = ida_alloc_max(&gman->gmr_ida, gman->max_gmr_ids - 1, GFP_KERNEL);
+       if (id < 0)
+               return id;
+
        spin_lock(&gman->lock);
 
        if (gman->max_gmr_pages > 0) {
                gman->used_gmr_pages += bo->num_pages;
                if (unlikely(gman->used_gmr_pages > gman->max_gmr_pages))
-                       goto out_err_locked;
+                       goto nospace;
        }
 
-       do {
-               spin_unlock(&gman->lock);
-               if (unlikely(ida_pre_get(&gman->gmr_ida, GFP_KERNEL) == 0)) {
-                       ret = -ENOMEM;
-                       goto out_err;
-               }
-               spin_lock(&gman->lock);
-
-               ret = ida_get_new(&gman->gmr_ida, &id);
-               if (unlikely(ret == 0 && id >= gman->max_gmr_ids)) {
-                       ida_remove(&gman->gmr_ida, id);
-                       ret = 0;
-                       goto out_err_locked;
-               }
-       } while (ret == -EAGAIN);
-
-       if (likely(ret == 0)) {
-               mem->mm_node = gman;
-               mem->start = id;
-               mem->num_pages = bo->num_pages;
-       } else
-               goto out_err_locked;
+       mem->mm_node = gman;
+       mem->start = id;
+       mem->num_pages = bo->num_pages;
 
        spin_unlock(&gman->lock);
        return 0;
 
-out_err:
-       spin_lock(&gman->lock);
-out_err_locked:
+nospace:
        gman->used_gmr_pages -= bo->num_pages;
        spin_unlock(&gman->lock);
-       return ret;
+       ida_free(&gman->gmr_ida, id);
+       return 0;
 }
 
 static void vmw_gmrid_man_put_node(struct ttm_mem_type_manager *man,
@@ -105,8 +88,8 @@ static void vmw_gmrid_man_put_node(struct 
ttm_mem_type_manager *man,
                (struct vmwgfx_gmrid_man *)man->priv;
 
        if (mem->mm_node) {
+               ida_free(&gman->gmr_ida, mem->start);
                spin_lock(&gman->lock);
-               ida_remove(&gman->gmr_ida, mem->start);
                gman->used_gmr_pages -= mem->num_pages;
                spin_unlock(&gman->lock);
                mem->mm_node = NULL;
-- 
2.17.1