[SRU][M, J][PATCH 1/1] block: Move checking GENHD_FL_NO_PART to bdev_add_partition()

[Roxana Nicolescu]

From: Li Lingfeng <lilingfeng3 at huawei.com>

BugLink: https://bugs.launchpad.net/bugs/2049689

Commit 1a721de8489f ("block: don't add or resize partition on the disk
with GENHD_FL_NO_PART") prevented all operations about partitions on disks
with GENHD_FL_NO_PART in blkpg_do_ioctl() since they are meaningless.
However, it changed error code in some scenarios. So move checking
GENHD_FL_NO_PART to bdev_add_partition() to eliminate impact.

Fixes: 1a721de8489f ("block: don't add or resize partition on the disk with GENHD_FL_NO_PART")
Reported-by: Allison Karlitskaya <allison.karlitskaya at redhat.com>
Closes: https://lore.kernel.org/all/CAOYeF9VsmqKMcQjo1k6YkGNujwN-nzfxY17N3F-CMikE1tYp+w@mail.gmail.com/
Signed-off-by: Li Lingfeng <lilingfeng3 at huawei.com>
Reviewed-by: Yu Kuai <yukuai3 at huawei.com>
Link: https://lore.kernel.org/r/20240118130401.792757-1-lilingfeng@huaweicloud.com
Signed-off-by: Jens Axboe <axboe at kernel.dk>
(cherry picked from commit 7777f47f2ea64efd1016262e7b59fab34adfb869)
Signed-off-by: Roxana Nicolescu <roxana.nicolescu at canonical.com>
---
 block/ioctl.c           | 2 --
 block/partitions/core.c | 5 +++++
 2 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/block/ioctl.c b/block/ioctl.c
index 9fcddd847937..3be11941fb2d 100644
--- a/block/ioctl.c
+++ b/block/ioctl.c
@@ -20,8 +20,6 @@ static int blkpg_do_ioctl(struct block_device *bdev,
 	struct blkpg_partition p;
 	long long start, length;
 
-	if (disk->flags & GENHD_FL_NO_PART)
-		return -EINVAL;
 	if (!capable(CAP_SYS_ADMIN))
 		return -EACCES;
 	if (copy_from_user(&p, upart, sizeof(struct blkpg_partition)))
diff --git a/block/partitions/core.c b/block/partitions/core.c
index 13a7341299a9..04d2143bca34 100644
--- a/block/partitions/core.c
+++ b/block/partitions/core.c
@@ -461,6 +461,11 @@ int bdev_add_partition(struct gendisk *disk, int partno, sector_t start,
 		goto out;
 	}
 
+	if (disk->flags & GENHD_FL_NO_PART) {
+		ret = -EINVAL;
+		goto out;
+	}
+
 	if (partition_overlaps(disk, start, length, -1)) {
 		ret = -EBUSY;
 		goto out;
-- 
2.34.1