[PATCH 1/2] block: move partitions check code into single helper

[Ming Lei]

No functional change, make code more readable, and prepare for
supporting safe re-read partitions.

Cc: Ewan D. Milne <emi...@redhat.com>
Signed-off-by: Ming Lei <ming....@redhat.com>
---
 block/partitions/core.c | 51 ++++++++++++++++++++++++++++++-----------
 1 file changed, 37 insertions(+), 14 deletions(-)

diff --git a/block/partitions/core.c b/block/partitions/core.c
index b1cdf88f96e2..154013ea8623 100644
--- a/block/partitions/core.c
+++ b/block/partitions/core.c
@@ -599,17 +599,15 @@ static bool blk_add_partition(struct gendisk *disk, 
struct block_device *bdev,
        return true;
 }
 
-int blk_add_partitions(struct gendisk *disk, struct block_device *bdev)
+static int blk_check_partitions(struct gendisk *disk,
+               struct block_device *bdev, struct parsed_partitions **s)
 {
-       struct parsed_partitions *state;
-       int ret = -EAGAIN, p;
-
-       if (!disk_part_scan_enabled(disk))
-               return 0;
+       int ret = -EAGAIN;
+       struct parsed_partitions *state = check_partition(disk, bdev);
 
-       state = check_partition(disk, bdev);
        if (!state)
-               return 0;
+               goto out;
+
        if (IS_ERR(state)) {
                /*
                 * I/O error reading the partition table.  If we tried to read
@@ -647,15 +645,40 @@ int blk_add_partitions(struct gendisk *disk, struct 
block_device *bdev)
                        goto out_free_state;
        }
 
+out:
+       *s = state;
+       return 0;
+
+out_free_state:
+       free_partitions(state);
+       *s = NULL;
+       return ret;
+}
+
+int blk_add_partitions(struct gendisk *disk, struct block_device *bdev)
+{
+       struct parsed_partitions *state;
+       int ret, p;
+
+       if (!disk_part_scan_enabled(disk))
+               return 0;
+
+       ret = blk_check_partitions(disk, bdev, &state);
+       if (ret != 0)
+               return ret;
+
+       if (!state)
+               return 0;
+
        /* tell userspace that the media / partition table may have changed */
        kobject_uevent(&disk_to_dev(disk)->kobj, KOBJ_CHANGE);
 
-       for (p = 1; p < state->limit; p++)
-               if (!blk_add_partition(disk, bdev, state, p))
-                       goto out_free_state;
-
-       ret = 0;
-out_free_state:
+       for (p = 1; p < state->limit; p++) {
+               if (!blk_add_partition(disk, bdev, state, p)) {
+                       ret = -EAGAIN;
+                       break;
+               }
+       }
        free_partitions(state);
        return ret;
 }
-- 
2.29.2