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Subject[PATCH] f2fs: Fix type of single bit bitfield in f2fs_io_info
Clang warns:

../fs/f2fs/data.c:995:17: error: implicit truncation from 'int' to a one-bit wide bit-field changes value from 1 to -1 [-Werror,-Wsingle-bit-bitfield-constant-conversion]
fio->submitted = 1;
^ ~
../fs/f2fs/data.c:1011:15: error: implicit truncation from 'int' to a one-bit wide bit-field changes value from 1 to -1 [-Werror,-Wsingle-bit-bitfield-constant-conversion]
fio->retry = 1;
^ ~

../fs/f2fs/segment.c:3320:16: error: implicit truncation from 'int' to a one-bit wide bit-field changes value from 1 to -1 [-Werror,-Wsingle-bit-bitfield-constant-conversion]
fio->in_list = 1;
^ ~

There is not a bug here because the value of these fields is never
explicitly compared against (just whether it is zero or non-zero) but
it is easy to silence the warning by using an unsigned type to allow
an assignment of 0 or 1 without implicit conversion.

Fixes: 998863dadd2c ("f2fs: reduce stack memory cost by using bitfield in struct f2fs_io_info")
Link: https://github.com/ClangBuiltLinux/linux/issues/1796
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
---
fs/f2fs/f2fs.h | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 08dc64c5050e..89f6fdfeed19 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -1213,12 +1213,12 @@ struct f2fs_io_info {
int compr_blocks; /* # of compressed block addresses */
int need_lock:8; /* indicate we need to lock cp_rwsem */
int version:8; /* version of the node */
- int submitted:1; /* indicate IO submission */
- int in_list:1; /* indicate fio is in io_list */
- int is_por:1; /* indicate IO is from recovery or not */
- int retry:1; /* need to reallocate block address */
- int encrypted:1; /* indicate file is encrypted */
- int post_read:1; /* require post read */
+ unsigned int submitted:1; /* indicate IO submission */
+ unsigned int in_list:1; /* indicate fio is in io_list */
+ unsigned int is_por:1; /* indicate IO is from recovery or not */
+ unsigned int retry:1; /* need to reallocate block address */
+ unsigned int encrypted:1; /* indicate file is encrypted */
+ unsigned int post_read:1; /* require post read */
enum iostat_type io_type; /* io type */
struct writeback_control *io_wbc; /* writeback control */
struct bio **bio; /* bio for ipu */
---
base-commit: de6b3a5e09b29c014bd04044b023896107cfa2ee
change-id: 20230201-f2fs-fix-single-length-bitfields-df8cc78e880a
Best regards,
--
Nathan Chancellor <nathan@kernel.org>

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