ext4: add ext4_sb_block_valid() refactored out of ext4_inode_block_valid()

stable inclusion
from stable-v5.10.175
commit 65061f49a50f8a303af61e9328e94a6c51ea4ab1
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I8711T

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=65061f49a50f8a303af61e9328e94a6c51ea4ab1



--------------------------------

commit 6bc6c2bd upstream.

This API will be needed at places where we don't have an inode
for e.g. while freeing blocks in ext4_group_add_blocks()

Suggested-by: Jan Kara <jack@suse.cz>
Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com>
Link: https://lore.kernel.org/r/dd34a236543ad5ae7123eeebe0cb69e6bdd44f34.1644992610.git.riteshh@linux.ibm.com


Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: sanglipeng <sanglipeng1@jd.com>