Re: [PATCH v6 06/12] xfs: add xfs_remount_rw() helper

Darrick J. Wong
2019-10-16T18:29:28Z

On Wed, Oct 16, 2019 at 08:41:13AM +0800, Ian Kent wrote:
> Factor the remount read write code into a helper to simplify the
> subsequent change from the super block method .remount_fs to the
> mount-api fs_context_operations method .reconfigure.
>
> Signed-off-by: Ian Kent <raven@themaw.net>
> Reviewed-by: Brian Foster <bfoster@redhat.com>
> ---
> fs/xfs/xfs_super.c | 115 +++++++++++++++++++++++++++++-----------------------
> 1 file changed, 64 insertions(+), 51 deletions(-)
>
> diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c
> index f8770206b66e..cdc19c2af50f 100644
> --- a/fs/xfs/xfs_super.c
> +++ b/fs/xfs/xfs_super.c
> @@ -1213,6 +1213,68 @@ xfs_test_remount_options(
> return error;
> }
>
> +static int
> +xfs_remount_rw(
> + struct xfs_mount *mp)
> +{
> + xfs_sb_t *sbp = &mp->m_sb;
> + int error;

Don't use typedefs (as hch said) and please indent all the variables,
not just some of them.

--D

> +
> + if (mp->m_flags & XFS_MOUNT_NORECOVERY) {
> + xfs_warn(mp,
> + "ro->rw transition prohibited on norecovery mount");
> + return -EINVAL;
> + }
> +
> + if (XFS_SB_VERSION_NUM(sbp) == XFS_SB_VERSION_5 &&
> + xfs_sb_has_ro_compat_feature(sbp, XFS_SB_FEAT_RO_COMPAT_UNKNOWN)) {
> + xfs_warn(mp,
> + "ro->rw transition prohibited on unknown (0x%x) ro-compat filesystem",
> + (sbp->sb_features_ro_compat &
> + XFS_SB_FEAT_RO_COMPAT_UNKNOWN));
> + return -EINVAL;
> + }
> +
> + mp->m_flags &= ~XFS_MOUNT_RDONLY;
> +
> + /*
> + * If this is the first remount to writeable state we
> + * might have some superblock changes to update.
> + */
> + if (mp->m_update_sb) {
> + error = xfs_sync_sb(mp, false);
> + if (error) {
> + xfs_warn(mp, "failed to write sb changes");
> + return error;
> + }
> + mp->m_update_sb = false;
> + }
> +
> + /*
> + * Fill out the reserve pool if it is empty. Use the stashed
> + * value if it is non-zero, otherwise go with the default.
> + */
> + xfs_restore_resvblks(mp);
> + xfs_log_work_queue(mp);
> +
> + /* Recover any CoW blocks that never got remapped. */
> + error = xfs_reflink_recover_cow(mp);
> + if (error) {
> + xfs_err(mp,
> + "Error %d recovering leftover CoW allocations.", error);
> + xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
> + return error;
> + }
> + xfs_start_block_reaping(mp);
> +
> + /* Create the per-AG metadata reservation pool .*/
> + error = xfs_fs_reserve_ag_blocks(mp);
> + if (error && error != -ENOSPC)
> + return error;
> +
> + return 0;
> +}
> +
> STATIC int
> xfs_fs_remount(
> struct super_block *sb,
> @@ -1276,57 +1338,8 @@ xfs_fs_remount(
>
> /* ro -> rw */
> if ((mp->m_flags & XFS_MOUNT_RDONLY) && !(*flags & SB_RDONLY)) {
> - if (mp->m_flags & XFS_MOUNT_NORECOVERY) {
> - xfs_warn(mp,
> - "ro->rw transition prohibited on norecovery mount");
> - return -EINVAL;
> - }
> -
> - if (XFS_SB_VERSION_NUM(sbp) == XFS_SB_VERSION_5 &&
> - xfs_sb_has_ro_compat_feature(sbp,
> - XFS_SB_FEAT_RO_COMPAT_UNKNOWN)) {
> - xfs_warn(mp,
> -"ro->rw transition prohibited on unknown (0x%x) ro-compat filesystem",
> - (sbp->sb_features_ro_compat &
> - XFS_SB_FEAT_RO_COMPAT_UNKNOWN));
> - return -EINVAL;
> - }
> -
> - mp->m_flags &= ~XFS_MOUNT_RDONLY;
> -
> - /*
> - * If this is the first remount to writeable state we
> - * might have some superblock changes to update.
> - */
> - if (mp->m_update_sb) {
> - error = xfs_sync_sb(mp, false);
> - if (error) {
> - xfs_warn(mp, "failed to write sb changes");
> - return error;
> - }
> - mp->m_update_sb = false;
> - }
> -
> - /*
> - * Fill out the reserve pool if it is empty. Use the stashed
> - * value if it is non-zero, otherwise go with the default.
> - */
> - xfs_restore_resvblks(mp);
> - xfs_log_work_queue(mp);
> -
> - /* Recover any CoW blocks that never got remapped. */
> - error = xfs_reflink_recover_cow(mp);
> - if (error) {
> - xfs_err(mp,
> - "Error %d recovering leftover CoW allocations.", error);
> - xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
> - return error;
> - }
> - xfs_start_block_reaping(mp);
> -
> - /* Create the per-AG metadata reservation pool .*/
> - error = xfs_fs_reserve_ag_blocks(mp);
> - if (error && error != -ENOSPC)
> + error = xfs_remount_rw(mp);
> + if (error)
> return error;
> }
>
>