md/md-bitmap: simplify md_bitmap_create() + md_bitmap_load()

Other than internal api get_bitmap_from_slot(), all other places will
set returned bitmap to mddev->bitmap. So move the setting of
mddev->bitmap into md_bitmap_create() to simplify code.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Link: https://lore.kernel.org/r/20240826074452.1490072-13-yukuai1@huaweicloud.comSigned-off-by: Song Liu <song@kernel.org>

drivers/md/md-bitmap.c

@@ -1879,7 +1879,7 @@ void md_bitmap_destroy(struct mddev *mddev)
  * if this returns an error, bitmap_destroy must be called to do clean up
  * once mddev->bitmap is set
  */
-struct bitmap *md_bitmap_create(struct mddev *mddev, int slot)
+static struct bitmap *__bitmap_create(struct mddev *mddev, int slot)
 {
 	struct bitmap *bitmap;
 	sector_t blocks = mddev->resync_max_sectors;
@@ -1966,6 +1966,17 @@ struct bitmap *md_bitmap_create(struct mddev *mddev, int slot)
 	return ERR_PTR(err);
 }
 
+int md_bitmap_create(struct mddev *mddev, int slot)
+{
+	struct bitmap *bitmap = __bitmap_create(mddev, slot);
+
+	if (IS_ERR(bitmap))
+		return PTR_ERR(bitmap);
+
+	mddev->bitmap = bitmap;
+	return 0;
+}
+
 int md_bitmap_load(struct mddev *mddev)
 {
 	int err = 0;
@@ -2030,7 +2041,7 @@ struct bitmap *get_bitmap_from_slot(struct mddev *mddev, int slot)
 	int rv = 0;
 	struct bitmap *bitmap;
 
-	bitmap = md_bitmap_create(mddev, slot);
+	bitmap = __bitmap_create(mddev, slot);
 	if (IS_ERR(bitmap)) {
 		rv = PTR_ERR(bitmap);
 		return ERR_PTR(rv);
@@ -2384,7 +2395,6 @@ location_store(struct mddev *mddev, const char *buf, size_t len)
 	} else {
 		/* No bitmap, OK to set a location */
 		long long offset;
-		struct bitmap *bitmap;
 
 		if (strncmp(buf, "none", 4) == 0)
 			/* nothing to be done */;
@@ -2411,13 +2421,10 @@ location_store(struct mddev *mddev, const char *buf, size_t len)
 			}
 
 			mddev->bitmap_info.offset = offset;
-			bitmap = md_bitmap_create(mddev, -1);
-			if (IS_ERR(bitmap)) {
-				rv = PTR_ERR(bitmap);
+			rv = md_bitmap_create(mddev, -1);
+			if (rv)
 				goto out;
-			}
 
-			mddev->bitmap = bitmap;
 			rv = md_bitmap_load(mddev);
 			if (rv) {
 				mddev->bitmap_info.offset = 0;

drivers/md/md-bitmap.h

@@ -253,7 +253,7 @@ struct bitmap_operations {
 void mddev_set_bitmap_ops(struct mddev *mddev);
 
 /* these are used only by md/bitmap */
-struct bitmap *md_bitmap_create(struct mddev *mddev, int slot);
+int md_bitmap_create(struct mddev *mddev, int slot);
 int md_bitmap_load(struct mddev *mddev);
 void md_bitmap_flush(struct mddev *mddev);
 void md_bitmap_destroy(struct mddev *mddev);

drivers/md/md.c

@@ -6224,16 +6224,10 @@ int md_run(struct mddev *mddev)
 	}
 	if (err == 0 && pers->sync_request &&
 	    (mddev->bitmap_info.file || mddev->bitmap_info.offset)) {
-		struct bitmap *bitmap;
-
-		bitmap = md_bitmap_create(mddev, -1);
-		if (IS_ERR(bitmap)) {
-			err = PTR_ERR(bitmap);
+		err = md_bitmap_create(mddev, -1);
+		if (err)
 			pr_warn("%s: failed to create bitmap (%d)\n",
 				mdname(mddev), err);
-		} else
-			mddev->bitmap = bitmap;
-
 	}
 	if (err)
 		goto bitmap_abort;
@@ -7288,14 +7282,10 @@ static int set_bitmap_file(struct mddev *mddev, int fd)
 	err = 0;
 	if (mddev->pers) {
 		if (fd >= 0) {
-			struct bitmap *bitmap;
-
-			bitmap = md_bitmap_create(mddev, -1);
-			if (!IS_ERR(bitmap)) {
-				mddev->bitmap = bitmap;
+			err = md_bitmap_create(mddev, -1);
+			if (!err)
 				err = md_bitmap_load(mddev);
-			} else
-				err = PTR_ERR(bitmap);
+
 			if (err) {
 				md_bitmap_destroy(mddev);
 				fd = -1;
@@ -7304,6 +7294,7 @@ static int set_bitmap_file(struct mddev *mddev, int fd)
 			md_bitmap_destroy(mddev);
 		}
 	}
+
 	if (fd < 0) {
 		struct file *f = mddev->bitmap_info.file;
 		if (f) {
@@ -7572,7 +7563,6 @@ static int update_array_info(struct mddev *mddev, mdu_array_info_t *info)
 			goto err;
 		}
 		if (info->state & (1<<MD_SB_BITMAP_PRESENT)) {
-			struct bitmap *bitmap;
 			/* add the bitmap */
 			if (mddev->bitmap) {
 				rv = -EEXIST;
@@ -7586,12 +7576,10 @@ static int update_array_info(struct mddev *mddev, mdu_array_info_t *info)
 				mddev->bitmap_info.default_offset;
 			mddev->bitmap_info.space =
 				mddev->bitmap_info.default_space;
-			bitmap = md_bitmap_create(mddev, -1);
-			if (!IS_ERR(bitmap)) {
-				mddev->bitmap = bitmap;
+			rv = md_bitmap_create(mddev, -1);
+			if (!rv)
 				rv = md_bitmap_load(mddev);
-			} else
-				rv = PTR_ERR(bitmap);
+
 			if (rv)
 				md_bitmap_destroy(mddev);
 		} else {