XArray: Change xa_for_each iterator

There were three problems with this API:
1. It took too many arguments; almost all users wanted to iterate over
every element in the array rather than a subset.
2. It required that 'index' be initialised before use, and there's no
realistic way to make GCC catch that.
3. 'index' and 'entry' were the opposite way round from every other
member of the XArray APIs.

So split it into three different APIs:

xa_for_each(xa, index, entry)
xa_for_each_start(xa, index, entry, start)
xa_for_each_marked(xa, index, entry, filter)

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

1 files changed, 5 insertions, 6 deletions

diff --git a/lib/test_xarray.c b/lib/test_xarray.c
index a885afde0aef..dc02eff562b8 100644
--- a/lib/test_xarray.c
+++ b/lib/test_xarray.c
@@ -357,7 +357,7 @@ static noinline void check_cmpxchg(struct xarray *xa)
 static noinline void check_reserve(struct xarray *xa)
 {
         void *entry;
-        unsigned long index = 0;
+        unsigned long index;
 
         /* An array with a reserved entry is not empty */
         XA_BUG_ON(xa, !xa_empty(xa));
@@ -393,7 +393,7 @@ static noinline void check_reserve(struct xarray *xa)
         xa_reserve(xa, 6, GFP_KERNEL);
         xa_store_index(xa, 7, GFP_KERNEL);
 
-        xa_for_each(xa, entry, index, ULONG_MAX, XA_PRESENT) {
+        xa_for_each(xa, index, entry) {
                 XA_BUG_ON(xa, index != 5 && index != 7);
         }
         xa_destroy(xa);
@@ -812,17 +812,16 @@ static noinline void check_find_1(struct xarray *xa)
 static noinline void check_find_2(struct xarray *xa)
 {
         void *entry;
-        unsigned long i, j, index = 0;
+        unsigned long i, j, index;
 
-        xa_for_each(xa, entry, index, ULONG_MAX, XA_PRESENT) {
+        xa_for_each(xa, index, entry) {
                 XA_BUG_ON(xa, true);
         }
 
         for (i = 0; i < 1024; i++) {
                 xa_store_index(xa, index, GFP_KERNEL);
                 j = 0;
-                index = 0;
-                xa_for_each(xa, entry, index, ULONG_MAX, XA_PRESENT) {
+                xa_for_each(xa, index, entry) {
                         XA_BUG_ON(xa, xa_mk_index(index) != entry);
                         XA_BUG_ON(xa, index != j++);
                 }