On Wed 20-07-22 16:30:29, zengjx95@xxxxxxxxx wrote:
> From: Zeng Jingxiang <linuszeng@xxxxxxxxxxx>
>
> Since commit 27b3a5c51b50 ("kill-the-bkl/reiserfs: drop the fs race
> watchdog from _get_block_create_0()"), which removed a label that may
> have the pointer 'p' touched in its control flow, related if statements
> now eval to constant value now. Just remove them.
>
> Assigning value NULL to p here
> 293 char *p = NULL;
>
> In the following conditional expression, the value of p is always NULL,
> As a result, the kunmap() cannot be executed.
> 308 if (p)
> 309 kunmap(bh_result->b_page);
>
> 355 if (p)
> 356 kunmap(bh_result->b_page);
>
> 366 if (p)
> 367 kunmap(bh_result->b_page);
>
> Also, the kmap() cannot be executed.
> 399 if (!p)
> 400 p = (char *)kmap(bh_result->b_page);
>
> Signed-off-by: Zeng Jingxiang <linuszeng@xxxxxxxxxxx>
> Signed-off-by: Kairui Song <kasong@xxxxxxxxxxx>
Thanks! I've added the patch to my tree. I've also removed the unnecessary
initialization of 'p' to NULL. I'll push the patch to Linus in the coming
merge window.
Honza
> ---
> fs/reiserfs/inode.c | 10 +---------
> 1 file changed, 1 insertion(+), 9 deletions(-)
>
> diff --git a/fs/reiserfs/inode.c b/fs/reiserfs/inode.c
> index 0cffe054b78e..fe26e1746af9 100644
> --- a/fs/reiserfs/inode.c
> +++ b/fs/reiserfs/inode.c
> @@ -305,8 +305,6 @@ static int _get_block_create_0(struct inode *inode, sector_t block,
> result = search_for_position_by_key(inode->i_sb, &key, &path);
> if (result != POSITION_FOUND) {
> pathrelse(&path);
> - if (p)
> - kunmap(bh_result->b_page);
> if (result == IO_ERROR)
> return -EIO;
> /*
> @@ -352,8 +350,6 @@ static int _get_block_create_0(struct inode *inode, sector_t block,
> }
>
> pathrelse(&path);
> - if (p)
> - kunmap(bh_result->b_page);
> return ret;
> }
> /* requested data are in direct item(s) */
> @@ -363,8 +359,6 @@ static int _get_block_create_0(struct inode *inode, sector_t block,
> * when it is stored in direct item(s)
> */
> pathrelse(&path);
> - if (p)
> - kunmap(bh_result->b_page);
> return -ENOENT;
> }
>
> @@ -396,9 +390,7 @@ static int _get_block_create_0(struct inode *inode, sector_t block,
> * sure we need to. But, this means the item might move if
> * kmap schedules
> */
> - if (!p)
> - p = (char *)kmap(bh_result->b_page);
> -
> + p = (char *)kmap(bh_result->b_page);
> p += offset;
> memset(p, 0, inode->i_sb->s_blocksize);
> do {
> --
> 2.27.0
>
--
Jan Kara <jack@xxxxxxxx>
SUSE Labs, CR
