On 1/19/22 6:21 PM, Darrick J. Wong wrote:
> From: Darrick J. Wong <djwong@xxxxxxxxxx>
>
> When we're preparing to move a list of xfs_buf(fers) to the freelist, be
> sure to detach the perag reference so that we don't leak the reference
> or leave dangling pointers. Currently this has no negative effects
> since we only call libxfs_bulkrelse while exiting programs, but let's
> not be sloppy.
>
> Signed-off-by: Darrick J. Wong <djwong@xxxxxxxxxx>
Seems fine
Reviewed-by: Eric Sandeen <sandeen@xxxxxxxxxx>
> ---
> libxfs/rdwr.c | 23 +++++++++++++----------
> 1 file changed, 13 insertions(+), 10 deletions(-)
>
>
> diff --git a/libxfs/rdwr.c b/libxfs/rdwr.c
> index 2a9e8c98..b43527e4 100644
> --- a/libxfs/rdwr.c
> +++ b/libxfs/rdwr.c
> @@ -887,11 +887,19 @@ libxfs_buf_mark_dirty(
> bp->b_flags |= LIBXFS_B_DIRTY;
> }
>
> -/* Complain about (and remember) dropping dirty buffers. */
> -static void
> -libxfs_whine_dirty_buf(
> +/* Prepare a buffer to be sent to the MRU list. */
> +static inline void
> +libxfs_buf_prepare_mru(
> struct xfs_buf *bp)
> {
> + if (bp->b_pag)
> + xfs_perag_put(bp->b_pag);
> + bp->b_pag = NULL;
> +
> + if (!(bp->b_flags & LIBXFS_B_DIRTY))
> + return;
> +
> + /* Complain about (and remember) dropping dirty buffers. */
> fprintf(stderr, _("%s: Releasing dirty buffer to free list!\n"),
> progname);
>
> @@ -909,11 +917,7 @@ libxfs_brelse(
>
> if (!bp)
> return;
> - if (bp->b_flags & LIBXFS_B_DIRTY)
> - libxfs_whine_dirty_buf(bp);
> - if (bp->b_pag)
> - xfs_perag_put(bp->b_pag);
> - bp->b_pag = NULL;
> + libxfs_buf_prepare_mru(bp);
>
> pthread_mutex_lock(&xfs_buf_freelist.cm_mutex);
> list_add(&bp->b_node.cn_mru, &xfs_buf_freelist.cm_list);
> @@ -932,8 +936,7 @@ libxfs_bulkrelse(
> return 0 ;
>
> list_for_each_entry(bp, list, b_node.cn_mru) {
> - if (bp->b_flags & LIBXFS_B_DIRTY)
> - libxfs_whine_dirty_buf(bp);
> + libxfs_buf_prepare_mru(bp);
> count++;
> }
>
>
