LinuxKPi: idr: use macros for lock idr lock operations

Our idr implementation is using a mtx lock which in the past has
already caused problems (613723bac2).
In order to make it easier to tackle the problem start by factoring
out all the operations related to the idr->lock into macros as we
have often done in other parts of code as well.

Sponsored by:	The FreeBSD Foundation
MFC after:	3 days
Reviewed by:	wulf, emaste
Differential Revision: https://reviews.freebsd.org/D55392

sys/compat/linuxkpi/common/src/linux_idr.c

@@ -62,6 +62,13 @@ DPCPU_DEFINE_STATIC(struct linux_idr_cache, linux_idr_cache);
  */
 static MALLOC_DEFINE(M_IDR, "idr", "Linux IDR compat");
 
+#define	IDR_LOCK_INIT(_idr)	mtx_init(&(_idr)->lock, "idr", NULL, MTX_DEF);
+#define	IDR_LOCK_DESTROY(_idr)	mtx_destroy(&(_idr)->lock);
+#define	IDR_LOCK(_idr)		mtx_lock(&(_idr)->lock);
+#define	IDR_UNLOCK(_idr)	mtx_unlock(&(_idr)->lock);
+#define	IDR_LOCK_ASSERT(_idr)	mtx_assert(&(_idr)->lock, MA_OWNED);
+#define	IDR_LOCK_INITALIZED(_idr) mtx_initialized(&(_idr)->lock)
+
 static struct idr_layer *
 idr_preload_dequeue_locked(struct linux_idr_cache *lic)
 {
@@ -168,7 +175,7 @@ void
 idr_init(struct idr *idr)
 {
 	bzero(idr, sizeof(*idr));
-	mtx_init(&idr->lock, "idr", NULL, MTX_DEF);
+	IDR_LOCK_INIT(idr);
 }
 
 /* Only frees cached pages. */
@@ -182,17 +189,17 @@ idr_destroy(struct idr *idr)
 	 * without a idr_init(). Check if this is the case.  If we do not do this
 	 * then the mutex will panic while asserting that it is valid.
 	 */
-	if (mtx_initialized(&idr->lock) == 0)
+	if (IDR_LOCK_INITALIZED(idr) == 0)
 		return;
 
 	idr_remove_all(idr);
-	mtx_lock(&idr->lock);
+	IDR_LOCK(idr);
 	for (il = idr->free; il != NULL; il = iln) {
 		iln = il->ary[0];
 		free(il, M_IDR);
 	}
-	mtx_unlock(&idr->lock);
-	mtx_destroy(&idr->lock);
+	IDR_UNLOCK(idr);
+	IDR_LOCK_DESTROY(idr);
 }
 
 static void
@@ -215,11 +222,11 @@ void
 idr_remove_all(struct idr *idr)
 {
 
-	mtx_lock(&idr->lock);
+	IDR_LOCK(idr);
 	idr_remove_layer(idr->top, idr->layers - 1);
 	idr->top = NULL;
 	idr->layers = 0;
-	mtx_unlock(&idr->lock);
+	IDR_UNLOCK(idr);
 }
 
 static void *
@@ -266,9 +273,9 @@ idr_remove(struct idr *idr, int id)
 {
 	void *res;
 
-	mtx_lock(&idr->lock);
+	IDR_LOCK(idr);
 	res = idr_remove_locked(idr, id);
-	mtx_unlock(&idr->lock);
+	IDR_UNLOCK(idr);
 
 	return (res);
 }
@@ -298,7 +305,7 @@ idr_replace(struct idr *idr, void *ptr, int id)
 	void *res;
 	int idx;
 
-	mtx_lock(&idr->lock);
+	IDR_LOCK(idr);
 	il = idr_find_layer_locked(idr, id);
 	idx = id & IDR_MASK;
 
@@ -309,7 +316,7 @@ idr_replace(struct idr *idr, void *ptr, int id)
 		res = il->ary[idx];
 		il->ary[idx] = ptr;
 	}
-	mtx_unlock(&idr->lock);
+	IDR_UNLOCK(idr);
 	return (res);
 }
 
@@ -319,7 +326,7 @@ idr_find_locked(struct idr *idr, int id)
 	struct idr_layer *il;
 	void *res;
 
-	mtx_assert(&idr->lock, MA_OWNED);
+	IDR_LOCK_ASSERT(idr);
 	il = idr_find_layer_locked(idr, id);
 	if (il != NULL)
 		res = il->ary[id & IDR_MASK];
@@ -333,9 +340,9 @@ idr_find(struct idr *idr, int id)
 {
 	void *res;
 
-	mtx_lock(&idr->lock);
+	IDR_LOCK(idr);
 	res = idr_find_locked(idr, id);
-	mtx_unlock(&idr->lock);
+	IDR_UNLOCK(idr);
 	return (res);
 }
 
@@ -345,7 +352,7 @@ idr_get_next(struct idr *idr, int *nextidp)
 	void *res = NULL;
 	int id = *nextidp;
 
-	mtx_lock(&idr->lock);
+	IDR_LOCK(idr);
 	for (; id <= idr_max(idr); id++) {
 		res = idr_find_locked(idr, id);
 		if (res == NULL)
@@ -353,7 +360,7 @@ idr_get_next(struct idr *idr, int *nextidp)
 		*nextidp = id;
 		break;
 	}
-	mtx_unlock(&idr->lock);
+	IDR_UNLOCK(idr);
 	return (res);
 }
 
@@ -364,12 +371,12 @@ idr_pre_get(struct idr *idr, gfp_t gfp_mask)
 	struct idr_layer *head;
 	int need;
 
-	mtx_lock(&idr->lock);
+	IDR_LOCK(idr);
 	for (;;) {
 		need = idr->layers + 1;
 		for (il = idr->free; il != NULL; il = il->ary[0])
 			need--;
-		mtx_unlock(&idr->lock);
+		IDR_UNLOCK(idr);
 		if (need <= 0)
 			break;
 		for (head = NULL; need; need--) {
@@ -385,7 +392,7 @@ idr_pre_get(struct idr *idr, gfp_t gfp_mask)
 		}
 		if (head == NULL)
 			return (0);
-		mtx_lock(&idr->lock);
+		IDR_LOCK(idr);
 		il->ary[0] = idr->free;
 		idr->free = head;
 	}
@@ -435,7 +442,7 @@ idr_get_new_locked(struct idr *idr, void *ptr, int *idp)
 	int idx;
 	int id;
 
-	mtx_assert(&idr->lock, MA_OWNED);
+	IDR_LOCK_ASSERT(idr);
 
 	error = -EAGAIN;
 	/*
@@ -506,9 +513,9 @@ idr_get_new(struct idr *idr, void *ptr, int *idp)
 {
 	int retval;
 
-	mtx_lock(&idr->lock);
+	IDR_LOCK(idr);
 	retval = idr_get_new_locked(idr, ptr, idp);
-	mtx_unlock(&idr->lock);
+	IDR_UNLOCK(idr);
 	return (retval);
 }
 
@@ -522,7 +529,7 @@ idr_get_new_above_locked(struct idr *idr, void *ptr, int starting_id, int *idp)
 	int idx, sidx;
 	int id;
 
-	mtx_assert(&idr->lock, MA_OWNED);
+	IDR_LOCK_ASSERT(idr);
 
 	error = -EAGAIN;
 	/*
@@ -624,9 +631,9 @@ idr_get_new_above(struct idr *idr, void *ptr, int starting_id, int *idp)
 {
 	int retval;
 
-	mtx_lock(&idr->lock);
+	IDR_LOCK(idr);
 	retval = idr_get_new_above_locked(idr, ptr, starting_id, idp);
-	mtx_unlock(&idr->lock);
+	IDR_UNLOCK(idr);
 	return (retval);
 }
 
@@ -643,7 +650,7 @@ idr_alloc_locked(struct idr *idr, void *ptr, int start, int end)
 	int error;
 	int id;
 
-	mtx_assert(&idr->lock, MA_OWNED);
+	IDR_LOCK_ASSERT(idr);
 
 	if (unlikely(start < 0))
 		return (-EINVAL);
@@ -669,9 +676,9 @@ idr_alloc(struct idr *idr, void *ptr, int start, int end, gfp_t gfp_mask)
 {
 	int retval;
 
-	mtx_lock(&idr->lock);
+	IDR_LOCK(idr);
 	retval = idr_alloc_locked(idr, ptr, start, end);
-	mtx_unlock(&idr->lock);
+	IDR_UNLOCK(idr);
 	return (retval);
 }
 
@@ -680,13 +687,13 @@ idr_alloc_cyclic(struct idr *idr, void *ptr, int start, int end, gfp_t gfp_mask)
 {
 	int retval;
 
-	mtx_lock(&idr->lock);
+	IDR_LOCK(idr);
 	retval = idr_alloc_locked(idr, ptr, max(start, idr->next_cyclic_id), end);
 	if (unlikely(retval == -ENOSPC))
 		retval = idr_alloc_locked(idr, ptr, start, end);
 	if (likely(retval >= 0))
 		idr->next_cyclic_id = retval + 1;
-	mtx_unlock(&idr->lock);
+	IDR_UNLOCK(idr);
 	return (retval);
 }