diff --git a/fs/xfs/libxfs/xfs_bmap.c b/fs/xfs/libxfs/xfs_bmap.c index 11facb8a6b3a..34de6e6898c4 100644 --- a/fs/xfs/libxfs/xfs_bmap.c +++ b/fs/xfs/libxfs/xfs_bmap.c @@ -3428,6 +3428,7 @@ xfs_bmap_btalloc_at_eof( bool ag_only) { struct xfs_mount *mp = args->mp; + struct xfs_perag *caller_pag = args->pag; int error; /* @@ -3455,9 +3456,11 @@ xfs_bmap_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; @@ -3483,10 +3486,14 @@ xfs_bmap_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); + ASSERT(args->pag == NULL); + args->pag = caller_pag; + } if (error) return error; @@ -3545,12 +3552,13 @@ xfs_bmap_btalloc_filestreams( int stripe_align) { xfs_extlen_t blen = 0; - int error; + int error = 0; error = xfs_filestream_select_ag(ap, args, &blen); if (error) return error; + ASSERT(args->pag); /* * If we are in low space mode, then optimal allocation will fail so @@ -3559,22 +3567,31 @@ xfs_bmap_btalloc_filestreams( */ if (ap->tp->t_flags & XFS_TRANS_LOWMODE) { args->minlen = ap->minlen; + ASSERT(args->fsbno == NULLFSBLOCK); goto out_low_space; } args->minlen = xfs_bmap_select_minlen(ap, args, blen); - if (ap->aeof) { + if (ap->aeof) error = xfs_bmap_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); + +out_low_space: + /* + * 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; -out_low_space: return xfs_bmap_btalloc_low_space(ap, args); } diff --git a/fs/xfs/xfs_filestream.c b/fs/xfs/xfs_filestream.c index 81aebe3e09ba..523a3b8b5754 100644 --- a/fs/xfs/xfs_filestream.c +++ b/fs/xfs/xfs_filestream.c @@ -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; @@ -89,7 +87,7 @@ restart: break; /* Couldn't lock the AGF, skip this AG. */ err = 0; - goto next_ag; + continue; } /* Keep track of the AG with the most free blocks. */ @@ -146,16 +144,19 @@ restart: /* * 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 @@ restart: 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: @@ -236,7 +250,14 @@ 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); @@ -246,6 +267,8 @@ xfs_filestream_select_ag_mru( 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; @@ -253,12 +276,18 @@ xfs_filestream_select_ag_mru( /* * We are done if there's still enough contiguous free space to succeed. + * If there is very little free space before we start a filestreams + * allocation, we're almost guaranteed to fail to find a better AG with + * larger free space available so we don't even try. */ *agno = pag->pag_agno; - if (*blen >= args->maxlen) + if (*blen >= args->maxlen || (ap->tp->t_flags & XFS_TRANS_LOWMODE)) { + 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 = @@ -297,46 +326,38 @@ xfs_filestream_select_ag( struct xfs_inode *pip = NULL; xfs_agnumber_t agno; int flags = 0; - int error; + int error = 0; args->total = ap->total; *blen = 0; pip = xfs_filestream_get_parent(ap->ip); if (!pip) { - agno = 0; - goto out_select; + ap->blkno = XFS_AGB_TO_FSB(mp, 0, 0); + return 0; } error = xfs_filestream_select_ag_mru(ap, args, pip, &agno, blen); - if (error || *blen >= args->maxlen) + if (error) goto out_rele; - - ap->blkno = XFS_AGB_TO_FSB(args->mp, agno, 0); - xfs_bmap_adjacent(ap); - - /* - * If there is very little free space before we start a filestreams - * allocation, we're almost guaranteed to fail to find a better AG with - * larger free space available so we don't even try. - */ + if (*blen >= args->maxlen) + goto out_select; if (ap->tp->t_flags & XFS_TRANS_LOWMODE) goto out_select; + ap->blkno = XFS_AGB_TO_FSB(args->mp, agno, 0); + xfs_bmap_adjacent(ap); + *blen = ap->length; if (ap->datatype & XFS_ALLOC_USERDATA) flags |= XFS_PICK_USERDATA; if (ap->tp->t_flags & XFS_TRANS_LOWMODE) 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); + if (error) + goto out_rele; out_select: - ap->blkno = XFS_AGB_TO_FSB(mp, agno, 0); + ap->blkno = XFS_AGB_TO_FSB(mp, args->pag->pag_agno, 0); out_rele: xfs_irele(pip); return error;