Merge branch 'ida-4.19' of git://git.infradead.org/users/willy/linux-dax

Pull IDA updates from Matthew Wilcox:
 "A better IDA API:

      id = ida_alloc(ida, GFP_xxx);
      ida_free(ida, id);

  rather than the cumbersome ida_simple_get(), ida_simple_remove().

  The new IDA API is similar to ida_simple_get() but better named.  The
  internal restructuring of the IDA code removes the bitmap
  preallocation nonsense.

  I hope the net -200 lines of code is convincing"

* 'ida-4.19' of git://git.infradead.org/users/willy/linux-dax: (29 commits)
  ida: Change ida_get_new_above to return the id
  ida: Remove old API
  test_ida: check_ida_destroy and check_ida_alloc
  test_ida: Convert check_ida_conv to new API
  test_ida: Move ida_check_max
  test_ida: Move ida_check_leaf
  idr-test: Convert ida_check_nomem to new API
  ida: Start new test_ida module
  target/iscsi: Allocate session IDs from an IDA
  iscsi target: fix session creation failure handling
  drm/vmwgfx: Convert to new IDA API
  dmaengine: Convert to new IDA API
  ppc: Convert vas ID allocation to new IDA API
  media: Convert entity ID allocation to new IDA API
  ppc: Convert mmu context allocation to new IDA API
  Convert net_namespace to new IDA API
  cb710: Convert to new IDA API
  rsxx: Convert to new IDA API
  osd: Convert to new IDA API
  sd: Convert to new IDA API
  ...

1 files changed, 54 insertions, 14 deletions

diff --git a/include/linux/idr.h b/include/linux/idr.h
index 3e8215b2c371..3ec8628ce17f 100644
--- a/include/linux/idr.h
+++ b/include/linux/idr.h
@@ -236,34 +236,74 @@ struct ida {
 }
 #define DEFINE_IDA(name)	struct ida name = IDA_INIT(name)
 
-int ida_pre_get(struct ida *ida, gfp_t gfp_mask);
-int ida_get_new_above(struct ida *ida, int starting_id, int *p_id);
-void ida_remove(struct ida *ida, int id);
+int ida_alloc_range(struct ida *, unsigned int min, unsigned int max, gfp_t);
+void ida_free(struct ida *, unsigned int id);
 void ida_destroy(struct ida *ida);
 
-int ida_simple_get(struct ida *ida, unsigned int start, unsigned int end,
-		   gfp_t gfp_mask);
-void ida_simple_remove(struct ida *ida, unsigned int id);
+/**
+ * ida_alloc() - Allocate an unused ID.
+ * @ida: IDA handle.
+ * @gfp: Memory allocation flags.
+ *
+ * Allocate an ID between 0 and %INT_MAX, inclusive.
+ *
+ * Context: Any context.
+ * Return: The allocated ID, or %-ENOMEM if memory could not be allocated,
+ * or %-ENOSPC if there are no free IDs.
+ */
+static inline int ida_alloc(struct ida *ida, gfp_t gfp)
+{
+	return ida_alloc_range(ida, 0, ~0, gfp);
+}
 
-static inline void ida_init(struct ida *ida)
+/**
+ * ida_alloc_min() - Allocate an unused ID.
+ * @ida: IDA handle.
+ * @min: Lowest ID to allocate.
+ * @gfp: Memory allocation flags.
+ *
+ * Allocate an ID between @min and %INT_MAX, inclusive.
+ *
+ * Context: Any context.
+ * Return: The allocated ID, or %-ENOMEM if memory could not be allocated,
+ * or %-ENOSPC if there are no free IDs.
+ */
+static inline int ida_alloc_min(struct ida *ida, unsigned int min, gfp_t gfp)
 {
-	INIT_RADIX_TREE(&ida->ida_rt, IDR_RT_MARKER | GFP_NOWAIT);
+	return ida_alloc_range(ida, min, ~0, gfp);
 }
 
 /**
- * ida_get_new - allocate new ID
- * @ida:	idr handle
- * @p_id:	pointer to the allocated handle
+ * ida_alloc_max() - Allocate an unused ID.
+ * @ida: IDA handle.
+ * @max: Highest ID to allocate.
+ * @gfp: Memory allocation flags.
+ *
+ * Allocate an ID between 0 and @max, inclusive.
  *
- * Simple wrapper around ida_get_new_above() w/ @starting_id of zero.
+ * Context: Any context.
+ * Return: The allocated ID, or %-ENOMEM if memory could not be allocated,
+ * or %-ENOSPC if there are no free IDs.
  */
-static inline int ida_get_new(struct ida *ida, int *p_id)
+static inline int ida_alloc_max(struct ida *ida, unsigned int max, gfp_t gfp)
 {
-	return ida_get_new_above(ida, 0, p_id);
+	return ida_alloc_range(ida, 0, max, gfp);
 }
 
+static inline void ida_init(struct ida *ida)
+{
+	INIT_RADIX_TREE(&ida->ida_rt, IDR_RT_MARKER | GFP_NOWAIT);
+}
+
+#define ida_simple_get(ida, start, end, gfp)	\
+			ida_alloc_range(ida, start, (end) - 1, gfp)
+#define ida_simple_remove(ida, id)	ida_free(ida, id)
+
 static inline bool ida_is_empty(const struct ida *ida)
 {
 	return radix_tree_empty(&ida->ida_rt);
 }
+
+/* in lib/radix-tree.c */
+int ida_pre_get(struct ida *ida, gfp_t gfp_mask);
 #endif /* __IDR_H__ */