ppc: Convert vas ID allocation to new IDA API

Removes a custom spinlock and simplifies the code.  Also fix an
error where we could allocate one ID too many.

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

1 files changed, 4 insertions, 22 deletions

diff --git a/arch/powerpc/platforms/powernv/vas-window.c b/arch/powerpc/platforms/powernv/vas-window.c
index ff9f48812331..e59e0e60e5b5 100644
--- a/arch/powerpc/platforms/powernv/vas-window.c
+++ b/arch/powerpc/platforms/powernv/vas-window.c
@@ -515,35 +515,17 @@ int init_winctx_regs(struct vas_window *window, struct vas_winctx *winctx)
         return 0;
 }
 
-static DEFINE_SPINLOCK(vas_ida_lock);
-
 static void vas_release_window_id(struct ida *ida, int winid)
 {
-        spin_lock(&vas_ida_lock);
-        ida_remove(ida, winid);
-        spin_unlock(&vas_ida_lock);
+        ida_free(ida, winid);
 }
 
 static int vas_assign_window_id(struct ida *ida)
 {
-        int rc, winid;
-
-        do {
-                rc = ida_pre_get(ida, GFP_KERNEL);
-                if (!rc)
-                        return -EAGAIN;
-
-                spin_lock(&vas_ida_lock);
-                rc = ida_get_new(ida, &winid);
-                spin_unlock(&vas_ida_lock);
-        } while (rc == -EAGAIN);
-
-        if (rc)
-                return rc;
+        int winid = ida_alloc_max(ida, VAS_WINDOWS_PER_CHIP - 1, GFP_KERNEL);
 
-        if (winid > VAS_WINDOWS_PER_CHIP) {
-                pr_err("Too many (%d) open windows\n", winid);
-                vas_release_window_id(ida, winid);
+        if (winid == -ENOSPC) {
+                pr_err("Too many (%d) open windows\n", VAS_WINDOWS_PER_CHIP);
                 return -EAGAIN;
         }