diff options
Diffstat (limited to 'fs/xfs/libxfs/xfs_ag.c')
-rw-r--r-- | fs/xfs/libxfs/xfs_ag.c | 93 |
1 files changed, 77 insertions, 16 deletions
diff --git a/fs/xfs/libxfs/xfs_ag.c b/fs/xfs/libxfs/xfs_ag.c index bb0c700afe3c..86696a1c6891 100644 --- a/fs/xfs/libxfs/xfs_ag.c +++ b/fs/xfs/libxfs/xfs_ag.c @@ -44,16 +44,15 @@ xfs_perag_get( xfs_agnumber_t agno) { struct xfs_perag *pag; - int ref = 0; rcu_read_lock(); pag = radix_tree_lookup(&mp->m_perag_tree, agno); if (pag) { + trace_xfs_perag_get(pag, _RET_IP_); ASSERT(atomic_read(&pag->pag_ref) >= 0); - ref = atomic_inc_return(&pag->pag_ref); + atomic_inc(&pag->pag_ref); } rcu_read_unlock(); - trace_xfs_perag_get(mp, agno, ref, _RET_IP_); return pag; } @@ -68,7 +67,6 @@ xfs_perag_get_tag( { struct xfs_perag *pag; int found; - int ref; rcu_read_lock(); found = radix_tree_gang_lookup_tag(&mp->m_perag_tree, @@ -77,9 +75,9 @@ xfs_perag_get_tag( rcu_read_unlock(); return NULL; } - ref = atomic_inc_return(&pag->pag_ref); + trace_xfs_perag_get_tag(pag, _RET_IP_); + atomic_inc(&pag->pag_ref); rcu_read_unlock(); - trace_xfs_perag_get_tag(mp, pag->pag_agno, ref, _RET_IP_); return pag; } @@ -87,11 +85,68 @@ void xfs_perag_put( struct xfs_perag *pag) { - int ref; - + trace_xfs_perag_put(pag, _RET_IP_); ASSERT(atomic_read(&pag->pag_ref) > 0); - ref = atomic_dec_return(&pag->pag_ref); - trace_xfs_perag_put(pag->pag_mount, pag->pag_agno, ref, _RET_IP_); + atomic_dec(&pag->pag_ref); +} + +/* + * Active references for perag structures. This is for short term access to the + * per ag structures for walking trees or accessing state. If an AG is being + * shrunk or is offline, then this will fail to find that AG and return NULL + * instead. + */ +struct xfs_perag * +xfs_perag_grab( + struct xfs_mount *mp, + xfs_agnumber_t agno) +{ + struct xfs_perag *pag; + + rcu_read_lock(); + pag = radix_tree_lookup(&mp->m_perag_tree, agno); + if (pag) { + trace_xfs_perag_grab(pag, _RET_IP_); + if (!atomic_inc_not_zero(&pag->pag_active_ref)) + pag = NULL; + } + rcu_read_unlock(); + return pag; +} + +/* + * search from @first to find the next perag with the given tag set. + */ +struct xfs_perag * +xfs_perag_grab_tag( + struct xfs_mount *mp, + xfs_agnumber_t first, + int tag) +{ + struct xfs_perag *pag; + int found; + + rcu_read_lock(); + found = radix_tree_gang_lookup_tag(&mp->m_perag_tree, + (void **)&pag, first, 1, tag); + if (found <= 0) { + rcu_read_unlock(); + return NULL; + } + trace_xfs_perag_grab_tag(pag, _RET_IP_); + if (!atomic_inc_not_zero(&pag->pag_active_ref)) + pag = NULL; + rcu_read_unlock(); + return pag; +} + +void +xfs_perag_rele( + struct xfs_perag *pag) +{ + trace_xfs_perag_rele(pag, _RET_IP_); + if (atomic_dec_and_test(&pag->pag_active_ref)) + wake_up(&pag->pag_active_wq); } /* @@ -196,6 +251,10 @@ xfs_free_perag( cancel_delayed_work_sync(&pag->pag_blockgc_work); xfs_buf_hash_destroy(pag); + /* drop the mount's active reference */ + xfs_perag_rele(pag); + XFS_IS_CORRUPT(pag->pag_mount, + atomic_read(&pag->pag_active_ref) != 0); call_rcu(&pag->rcu_head, __xfs_free_perag); } } @@ -314,6 +373,7 @@ xfs_initialize_perag( INIT_DELAYED_WORK(&pag->pag_blockgc_work, xfs_blockgc_worker); INIT_RADIX_TREE(&pag->pag_ici_root, GFP_ATOMIC); init_waitqueue_head(&pag->pagb_wait); + init_waitqueue_head(&pag->pag_active_wq); pag->pagb_count = 0; pag->pagb_tree = RB_ROOT; #endif /* __KERNEL__ */ @@ -322,6 +382,9 @@ xfs_initialize_perag( if (error) goto out_remove_pag; + /* Active ref owned by mount indicates AG is online. */ + atomic_set(&pag->pag_active_ref, 1); + /* first new pag is fully initialized */ if (first_initialised == NULLAGNUMBER) first_initialised = index; @@ -824,7 +887,7 @@ xfs_ag_shrink_space( struct xfs_alloc_arg args = { .tp = *tpp, .mp = mp, - .type = XFS_ALLOCTYPE_THIS_BNO, + .pag = pag, .minlen = delta, .maxlen = delta, .oinfo = XFS_RMAP_OINFO_SKIP_UPDATE, @@ -856,14 +919,11 @@ xfs_ag_shrink_space( if (delta >= aglen) return -EINVAL; - args.fsbno = XFS_AGB_TO_FSB(mp, pag->pag_agno, aglen - delta); - /* * Make sure that the last inode cluster cannot overlap with the new * end of the AG, even if it's sparse. */ - error = xfs_ialloc_check_shrink(*tpp, pag->pag_agno, agibp, - aglen - delta); + error = xfs_ialloc_check_shrink(pag, *tpp, agibp, aglen - delta); if (error) return error; @@ -876,7 +936,8 @@ xfs_ag_shrink_space( return error; /* internal log shouldn't also show up in the free space btrees */ - error = xfs_alloc_vextent(&args); + error = xfs_alloc_vextent_exact_bno(&args, + XFS_AGB_TO_FSB(mp, pag->pag_agno, aglen - delta)); if (!error && args.agbno == NULLAGBLOCK) error = -ENOSPC; |