@@ -3438,6 +3438,7 @@ xfs_btalloc_at_eof(
bool ag_only)
{
struct xfs_mount *mp = args->mp;
+ struct xfs_perag *caller_pag = args->pag;
int error;
/*
@@ -3465,9 +3466,11 @@ xfs_btalloc_at_eof(
else
args->minalignslop = 0;
- args->pag = xfs_perag_get(mp, XFS_FSB_TO_AGNO(mp, ap->blkno));
+ if (!caller_pag)
+ args->pag = xfs_perag_get(mp, XFS_FSB_TO_AGNO(mp, ap->blkno));
error = xfs_alloc_vextent_exact_bno(args, ap->blkno);
- xfs_perag_put(args->pag);
+ if (!caller_pag)
+ xfs_perag_put(args->pag);
if (error)
return error;
@@ -3493,10 +3496,13 @@ xfs_btalloc_at_eof(
args->minalignslop = 0;
}
- if (ag_only)
+ if (ag_only) {
error = xfs_alloc_vextent_near_bno(args, ap->blkno);
- else
+ } else {
+ args->pag = NULL;
error = xfs_alloc_vextent_start_ag(args, ap->blkno);
+ args->pag = caller_pag;
+ }
if (error)
return error;
@@ -3559,16 +3565,25 @@ xfs_btalloc_filestreams(
error = xfs_filestream_select_ag(ap, args, &blen);
if (error)
return error;
+ ASSERT(args->pag);
args->minlen = xfs_bmap_select_minlen(ap, args, blen);
- if (ap->aeof) {
+ if (ap->aeof)
error = xfs_btalloc_at_eof(ap, args, blen, stripe_align, true);
- if (error || args->fsbno != NULLFSBLOCK)
- return error;
- }
- error = xfs_alloc_vextent_near_bno(args, ap->blkno);
+ if (!error && args->fsbno == NULLFSBLOCK)
+ error = xfs_alloc_vextent_near_bno(args, ap->blkno);
+
+ /*
+ * We are now done with the perag reference for the filestreams
+ * association provided by xfs_filestream_select_ag(). Release it now as
+ * we've either succeeded, had a fatal error or we are out of space and
+ * need to do a full filesystem scan for free space which will take it's
+ * own references.
+ */
+ xfs_perag_rele(args->pag);
+ args->pag = NULL;
if (error || args->fsbno != NULLFSBLOCK)
return error;
@@ -53,8 +53,9 @@ xfs_fstrm_free_func(
*/
static int
xfs_filestream_pick_ag(
+ struct xfs_alloc_arg *args,
struct xfs_inode *ip,
- xfs_agnumber_t *agp,
+ xfs_agnumber_t start_agno,
int flags,
xfs_extlen_t *longest)
{
@@ -64,7 +65,6 @@ xfs_filestream_pick_ag(
struct xfs_perag *max_pag = NULL;
xfs_extlen_t minlen = *longest;
xfs_extlen_t free = 0, minfree, maxfree = 0;
- xfs_agnumber_t start_agno = *agp;
xfs_agnumber_t agno;
int err, trylock;
@@ -73,8 +73,6 @@ xfs_filestream_pick_ag(
/* 2% of an AG's blocks must be free for it to be chosen. */
minfree = mp->m_sb.sb_agblocks / 50;
- *agp = NULLAGNUMBER;
-
/* For the first pass, don't sleep trying to init the per-AG. */
trylock = XFS_ALLOC_FLAG_TRYLOCK;
@@ -146,16 +144,19 @@ xfs_filestream_pick_ag(
/*
* No unassociated AGs are available, so select the AG with the
* most free space, regardless of whether it's already in use by
- * another filestream. It none suit, return NULLAGNUMBER.
+ * another filestream. It none suit, just use whatever AG we can
+ * grab.
*/
if (!max_pag) {
- *agp = NULLAGNUMBER;
- trace_xfs_filestream_pick(ip, NULL, free);
- return 0;
+ for_each_perag_wrap(mp, start_agno, agno, pag)
+ break;
+ atomic_inc(&pag->pagf_fstrms);
+ *longest = 0;
+ } else {
+ pag = max_pag;
+ free = maxfree;
+ atomic_inc(&pag->pagf_fstrms);
}
- pag = max_pag;
- free = maxfree;
- atomic_inc(&pag->pagf_fstrms);
} else if (max_pag) {
xfs_perag_rele(max_pag);
}
@@ -167,16 +168,29 @@ xfs_filestream_pick_ag(
if (!item)
goto out_put_ag;
+
+ /*
+ * We are going to use this perag now, so take another ref to it for the
+ * allocation context returned to the caller. If we raced to create and
+ * insert the filestreams item into the MRU (-EEXIST), then we still
+ * keep this reference but free the item reference we gained above. On
+ * any other failure, we have to drop both.
+ */
+ atomic_inc(&pag->pag_active_ref);
item->pag = pag;
+ args->pag = pag;
err = xfs_mru_cache_insert(mp->m_filestream, ip->i_ino, &item->mru);
if (err) {
- if (err == -EEXIST)
+ if (err == -EEXIST) {
err = 0;
+ } else {
+ xfs_perag_rele(args->pag);
+ args->pag = NULL;
+ }
goto out_free_item;
}
- *agp = pag->pag_agno;
return 0;
out_free_item:
@@ -237,7 +251,14 @@ xfs_filestream_select_ag_mru(
if (!mru)
goto out_default_agno;
+ /*
+ * Grab the pag and take an extra active reference for the caller whilst
+ * the mru item cannot go away. This means we'll pin the perag with
+ * the reference we get here even if the filestreams association is torn
+ * down immediately after we mark the lookup as done.
+ */
pag = container_of(mru, struct xfs_fstrm_item, mru)->pag;
+ atomic_inc(&pag->pag_active_ref);
xfs_mru_cache_done(mp->m_filestream);
trace_xfs_filestream_lookup(pag, ap->ip->i_ino);
@@ -245,19 +266,22 @@ xfs_filestream_select_ag_mru(
ap->blkno = XFS_AGB_TO_FSB(args->mp, pag->pag_agno, 0);
xfs_bmap_adjacent(ap);
-
error = xfs_bmap_longest_free_extent(pag, args->tp, blen);
if (error) {
+ /* We aren't going to use this perag */
+ xfs_perag_rele(pag);
if (error != -EAGAIN)
return error;
*blen = 0;
}
- *agno = pag->pag_agno;
- if (*blen >= args->maxlen)
+ if (*blen >= args->maxlen) {
+ args->pag = pag;
return 0;
+ }
/* Changing parent AG association now, so remove the existing one. */
+ xfs_perag_rele(pag);
mru = xfs_mru_cache_remove(mp->m_filestream, pip->i_ino);
if (mru) {
struct xfs_fstrm_item *item =
@@ -318,17 +342,12 @@ xfs_filestream_select_ag(
flags |= XFS_PICK_LOWSPACE;
*blen = ap->length;
- error = xfs_filestream_pick_ag(pip, &agno, flags, blen);
- if (agno == NULLAGNUMBER) {
- agno = 0;
- *blen = 0;
- }
-
+ error = xfs_filestream_pick_ag(args, pip, agno, flags, blen);
out_rele:
xfs_irele(pip);
out_select:
if (!error)
- ap->blkno = XFS_AGB_TO_FSB(mp, agno, 0);
+ ap->blkno = XFS_AGB_TO_FSB(mp, args->pag->pag_agno, 0);
return error;
}