diff options
| -rw-r--r-- | fs/xfs/xfs_discard.c | 146 |
1 files changed, 144 insertions, 2 deletions
diff --git a/fs/xfs/xfs_discard.c b/fs/xfs/xfs_discard.c index b7c1e09e9afe..c4bd145f5ec1 100644 --- a/fs/xfs/xfs_discard.c +++ b/fs/xfs/xfs_discard.c @@ -73,6 +73,8 @@ * extent search so that it overlaps in flight discard IO. */ +#define XFS_DISCARD_MAX_EXAMINE (100) + struct workqueue_struct *xfs_discard_wq; static void @@ -185,7 +187,7 @@ xfs_trim_gather_extents( struct xfs_buf *agbp; int error; int i; - int batch = 100; + int batch = XFS_DISCARD_MAX_EXAMINE; /* * Force out the log. This means any transactions that might have freed @@ -565,6 +567,7 @@ xfs_trim_gather_rtextent( return 0; } +/* Trim extents on an !rtgroups realtime device */ static int xfs_trim_rtextents( struct xfs_rtgroup *rtg, @@ -619,6 +622,140 @@ xfs_trim_rtextents( return error; } +struct xfs_trim_rtgroup { + /* list of rtgroup extents to free */ + struct xfs_busy_extents *extents; + + /* minimum length that caller allows us to trim */ + xfs_rtblock_t minlen_fsb; + + /* restart point for the rtbitmap walk */ + xfs_rtxnum_t restart_rtx; + + /* number of extents to examine before stopping to issue discard ios */ + int batch; + + /* number of extents queued for discard */ + int queued; +}; + +static int +xfs_trim_gather_rtgroup_extent( + struct xfs_rtgroup *rtg, + struct xfs_trans *tp, + const struct xfs_rtalloc_rec *rec, + void *priv) +{ + struct xfs_trim_rtgroup *tr = priv; + xfs_rgblock_t rgbno; + xfs_extlen_t len; + + if (--tr->batch <= 0) { + /* + * If we've checked a large number of extents, update the + * cursor to point at this extent so we restart the next batch + * from this extent. + */ + tr->restart_rtx = rec->ar_startext; + return -ECANCELED; + } + + rgbno = xfs_rtx_to_rgbno(rtg, rec->ar_startext); + len = xfs_rtxlen_to_extlen(rtg_mount(rtg), rec->ar_extcount); + + /* Ignore too small. */ + if (len < tr->minlen_fsb) { + trace_xfs_discard_toosmall(rtg_group(rtg), rgbno, len); + return 0; + } + + /* + * If any blocks in the range are still busy, skip the discard and try + * again the next time. + */ + if (xfs_extent_busy_search(rtg_group(rtg), rgbno, len)) { + trace_xfs_discard_busy(rtg_group(rtg), rgbno, len); + return 0; + } + + xfs_extent_busy_insert_discard(rtg_group(rtg), rgbno, len, + &tr->extents->extent_list); + + tr->queued++; + tr->restart_rtx = rec->ar_startext + rec->ar_extcount; + return 0; +} + +/* Trim extents in this rtgroup using the busy extent machinery. */ +static int +xfs_trim_rtgroup_extents( + struct xfs_rtgroup *rtg, + xfs_rtxnum_t low, + xfs_rtxnum_t high, + xfs_daddr_t minlen) +{ + struct xfs_mount *mp = rtg_mount(rtg); + struct xfs_trim_rtgroup tr = { + .minlen_fsb = XFS_BB_TO_FSB(mp, minlen), + }; + struct xfs_trans *tp; + int error; + + error = xfs_trans_alloc_empty(mp, &tp); + if (error) + return error; + + /* + * Walk the free ranges between low and high. The query_range function + * trims the extents returned. + */ + do { + tr.extents = kzalloc(sizeof(*tr.extents), GFP_KERNEL); + if (!tr.extents) { + error = -ENOMEM; + break; + } + + tr.queued = 0; + tr.batch = XFS_DISCARD_MAX_EXAMINE; + tr.extents->owner = tr.extents; + INIT_LIST_HEAD(&tr.extents->extent_list); + + xfs_rtgroup_lock(rtg, XFS_RTGLOCK_BITMAP_SHARED); + error = xfs_rtalloc_query_range(rtg, tp, low, high, + xfs_trim_gather_rtgroup_extent, &tr); + xfs_rtgroup_unlock(rtg, XFS_RTGLOCK_BITMAP_SHARED); + if (error == -ECANCELED) + error = 0; + if (error) { + kfree(tr.extents); + break; + } + + if (!tr.queued) + break; + + /* + * We hand the extent list to the discard function here so the + * discarded extents can be removed from the busy extent list. + * This allows the discards to run asynchronously with + * gathering the next round of extents to discard. + * + * However, we must ensure that we do not reference the extent + * list after this function call, as it may have been freed by + * the time control returns to us. + */ + error = xfs_discard_extents(rtg_mount(rtg), tr.extents); + if (error) + break; + + low = tr.restart_rtx; + } while (!xfs_trim_should_stop() && low <= high); + + xfs_trans_cancel(tp); + return error; +} + static int xfs_trim_rtdev_extents( struct xfs_mount *mp, @@ -657,7 +794,12 @@ xfs_trim_rtdev_extents( if (rtg_rgno(rtg) == end_rgno) rtg_end = min(rtg_end, end_rtx); - error = xfs_trim_rtextents(rtg, start_rtx, rtg_end, minlen); + if (xfs_has_rtgroups(mp)) + error = xfs_trim_rtgroup_extents(rtg, start_rtx, + rtg_end, minlen); + else + error = xfs_trim_rtextents(rtg, start_rtx, rtg_end, + minlen); if (error) last_error = error; |