Plumb in the upper level interface to schedule and finish deferred
refcount operations via the deferred ops mechanism.
Signed-off-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
---
include/xfs_trans.h | 1
libxfs/defer_item.c | 129 +++++++++++++++++++++++++++++++++++++
libxfs/init.c | 1
libxfs/xfs_defer.h | 1
libxfs/xfs_refcount.c | 170 +++++++++++++++++++++++++++++++++++++++++++++++++
libxfs/xfs_refcount.h | 12 +++
6 files changed, 314 insertions(+)
diff --git a/include/xfs_trans.h b/include/xfs_trans.h
index ab5d59b..739a792 100644
--- a/include/xfs_trans.h
+++ b/include/xfs_trans.h
@@ -147,5 +147,6 @@ libxfs_trans_read_buf(
void xfs_extent_free_init_defer_op(void);
void xfs_rmap_update_init_defer_op(void);
+void xfs_refcount_update_init_defer_op(void);
#endif /* __XFS_TRANS_H__ */
diff --git a/libxfs/defer_item.c b/libxfs/defer_item.c
index f60a11b..133e6e1 100644
--- a/libxfs/defer_item.c
+++ b/libxfs/defer_item.c
@@ -31,6 +31,7 @@
#include "xfs_bmap.h"
#include "xfs_alloc.h"
#include "xfs_rmap.h"
+#include "xfs_refcount.h"
/* Dummy defer item ops, since we don't do logging. */
@@ -257,3 +258,131 @@ xfs_rmap_update_init_defer_op(void)
{
xfs_defer_init_op_type(&xfs_rmap_update_defer_type);
}
+
+/* Reference Counting */
+
+/* Sort refcount intents by AG. */
+static int
+xfs_refcount_update_diff_items(
+ void *priv,
+ struct list_head *a,
+ struct list_head *b)
+{
+ struct xfs_mount *mp = priv;
+ struct xfs_refcount_intent *ra;
+ struct xfs_refcount_intent *rb;
+
+ ra = container_of(a, struct xfs_refcount_intent, ri_list);
+ rb = container_of(b, struct xfs_refcount_intent, ri_list);
+ return XFS_FSB_TO_AGNO(mp, ra->ri_startblock) -
+ XFS_FSB_TO_AGNO(mp, rb->ri_startblock);
+}
+
+/* Get an CUI. */
+STATIC void *
+xfs_refcount_update_create_intent(
+ struct xfs_trans *tp,
+ unsigned int count)
+{
+ return NULL;
+}
+
+/* Log refcount updates in the intent item. */
+STATIC void
+xfs_refcount_update_log_item(
+ struct xfs_trans *tp,
+ void *intent,
+ struct list_head *item)
+{
+}
+
+/* Get an CUD so we can process all the deferred refcount updates. */
+STATIC void *
+xfs_refcount_update_create_done(
+ struct xfs_trans *tp,
+ void *intent,
+ unsigned int count)
+{
+ return NULL;
+}
+
+/* Process a deferred refcount update. */
+STATIC int
+xfs_refcount_update_finish_item(
+ struct xfs_trans *tp,
+ struct xfs_defer_ops *dop,
+ struct list_head *item,
+ void *done_item,
+ void **state)
+{
+ struct xfs_refcount_intent *refc;
+ xfs_extlen_t adjusted;
+ int error;
+
+ refc = container_of(item, struct xfs_refcount_intent, ri_list);
+ error = xfs_refcount_finish_one(tp, dop,
+ refc->ri_type,
+ refc->ri_startblock,
+ refc->ri_blockcount,
+ &adjusted,
+ (struct xfs_btree_cur **)state);
+ /* Did we run out of reservation? Requeue what we didn't finish. */
+ if (!error && adjusted < refc->ri_blockcount) {
+ ASSERT(refc->ri_type == XFS_REFCOUNT_INCREASE ||
+ refc->ri_type == XFS_REFCOUNT_DECREASE);
+ refc->ri_startblock += adjusted;
+ refc->ri_blockcount -= adjusted;
+ return -EAGAIN;
+ }
+ kmem_free(refc);
+ return error;
+}
+
+/* Clean up after processing deferred refcounts. */
+STATIC void
+xfs_refcount_update_finish_cleanup(
+ struct xfs_trans *tp,
+ void *state,
+ int error)
+{
+ struct xfs_btree_cur *rcur = state;
+
+ xfs_refcount_finish_one_cleanup(tp, rcur, error);
+}
+
+/* Abort all pending CUIs. */
+STATIC void
+xfs_refcount_update_abort_intent(
+ void *intent)
+{
+}
+
+/* Cancel a deferred refcount update. */
+STATIC void
+xfs_refcount_update_cancel_item(
+ struct list_head *item)
+{
+ struct xfs_refcount_intent *refc;
+
+ refc = container_of(item, struct xfs_refcount_intent, ri_list);
+ kmem_free(refc);
+}
+
+static const struct xfs_defer_op_type xfs_refcount_update_defer_type = {
+ .type = XFS_DEFER_OPS_TYPE_REFCOUNT,
+ .diff_items = xfs_refcount_update_diff_items,
+ .create_intent = xfs_refcount_update_create_intent,
+ .abort_intent = xfs_refcount_update_abort_intent,
+ .log_item = xfs_refcount_update_log_item,
+ .create_done = xfs_refcount_update_create_done,
+ .finish_item = xfs_refcount_update_finish_item,
+ .finish_cleanup = xfs_refcount_update_finish_cleanup,
+ .cancel_item = xfs_refcount_update_cancel_item,
+};
+
+/* Register the deferred op type. */
+void
+xfs_refcount_update_init_defer_op(void)
+{
+ xfs_defer_init_op_type(&xfs_refcount_update_defer_type);
+}
diff --git a/libxfs/init.c b/libxfs/init.c
index 706925d..2d1bb58 100644
--- a/libxfs/init.c
+++ b/libxfs/init.c
@@ -266,6 +266,7 @@ libxfs_init(libxfs_init_t *a)
xfs_extent_free_init_defer_op();
xfs_rmap_update_init_defer_op();
+ xfs_refcount_update_init_defer_op();
radix_tree_init();
diff --git a/libxfs/xfs_defer.h b/libxfs/xfs_defer.h
index cc3981c..d47a482 100644
--- a/libxfs/xfs_defer.h
+++ b/libxfs/xfs_defer.h
@@ -51,6 +51,7 @@ struct xfs_defer_pending {
* find all the space it needs.
*/
enum xfs_defer_ops_type {
+ XFS_DEFER_OPS_TYPE_REFCOUNT,
XFS_DEFER_OPS_TYPE_RMAP,
XFS_DEFER_OPS_TYPE_FREE,
XFS_DEFER_OPS_TYPE_MAX,
diff --git a/libxfs/xfs_refcount.c b/libxfs/xfs_refcount.c
index 08866f8..31028bf 100644
--- a/libxfs/xfs_refcount.c
+++ b/libxfs/xfs_refcount.c
@@ -957,3 +957,173 @@ out_error:
error, _RET_IP_);
return error;
}
+
+/* Clean up after calling xfs_refcount_finish_one. */
+void
+xfs_refcount_finish_one_cleanup(
+ struct xfs_trans *tp,
+ struct xfs_btree_cur *rcur,
+ int error)
+{
+ struct xfs_buf *agbp;
+
+ if (rcur == NULL)
+ return;
+ agbp = rcur->bc_private.a.agbp;
+ xfs_btree_del_cursor(rcur, error ? XFS_BTREE_ERROR : XFS_BTREE_NOERROR);
+ if (error)
+ xfs_trans_brelse(tp, agbp);
+}
+
+/*
+ * Process one of the deferred refcount operations. We pass back the
+ * btree cursor to maintain our lock on the btree between calls.
+ * This saves time and eliminates a buffer deadlock between the
+ * superblock and the AGF because we'll always grab them in the same
+ * order.
+ */
+int
+xfs_refcount_finish_one(
+ struct xfs_trans *tp,
+ struct xfs_defer_ops *dfops,
+ enum xfs_refcount_intent_type type,
+ xfs_fsblock_t startblock,
+ xfs_extlen_t blockcount,
+ xfs_extlen_t *adjusted,
+ struct xfs_btree_cur **pcur)
+{
+ struct xfs_mount *mp = tp->t_mountp;
+ struct xfs_btree_cur *rcur;
+ struct xfs_buf *agbp = NULL;
+ int error = 0;
+ xfs_agnumber_t agno;
+ xfs_agblock_t bno;
+ unsigned long nr_ops = 0;
+ int shape_changes = 0;
+
+ agno = XFS_FSB_TO_AGNO(mp, startblock);
+ ASSERT(agno != NULLAGNUMBER);
+ bno = XFS_FSB_TO_AGBNO(mp, startblock);
+
+ trace_xfs_refcount_deferred(mp, XFS_FSB_TO_AGNO(mp, startblock),
+ type, XFS_FSB_TO_AGBNO(mp, startblock),
+ blockcount);
+
+ if (XFS_TEST_ERROR(false, mp,
+ XFS_ERRTAG_REFCOUNT_FINISH_ONE,
+ XFS_RANDOM_REFCOUNT_FINISH_ONE))
+ return -EIO;
+
+ /*
+ * If we haven't gotten a cursor or the cursor AG doesn't match
+ * the startblock, get one now.
+ */
+ rcur = *pcur;
+ if (rcur != NULL && rcur->bc_private.a.agno != agno) {
+ nr_ops = rcur->bc_private.a.priv.refc.nr_ops;
+ shape_changes = rcur->bc_private.a.priv.refc.shape_changes;
+ xfs_refcount_finish_one_cleanup(tp, rcur, 0);
+ rcur = NULL;
+ *pcur = NULL;
+ }
+ if (rcur == NULL) {
+ error = xfs_alloc_read_agf(tp->t_mountp, tp, agno,
+ XFS_ALLOC_FLAG_FREEING, &agbp);
+ if (error)
+ return error;
+ if (!agbp)
+ return -EFSCORRUPTED;
+
+ rcur = xfs_refcountbt_init_cursor(mp, tp, agbp, agno, dfops);
+ if (!rcur) {
+ error = -ENOMEM;
+ goto out_cur;
+ }
+ rcur->bc_private.a.priv.refc.nr_ops = nr_ops;
+ rcur->bc_private.a.priv.refc.shape_changes = shape_changes;
+ }
+ *pcur = rcur;
+
+ switch (type) {
+ case XFS_REFCOUNT_INCREASE:
+ error = xfs_refcount_adjust(rcur, bno, blockcount, adjusted,
+ XFS_REFCOUNT_ADJUST_INCREASE, dfops, NULL);
+ break;
+ case XFS_REFCOUNT_DECREASE:
+ error = xfs_refcount_adjust(rcur, bno, blockcount, adjusted,
+ XFS_REFCOUNT_ADJUST_DECREASE, dfops, NULL);
+ break;
+ default:
+ ASSERT(0);
+ error = -EFSCORRUPTED;
+ }
+ if (!error && *adjusted != blockcount)
+ trace_xfs_refcount_finish_one_leftover(mp, agno, type,
+ bno, blockcount, *adjusted);
+ return error;
+
+out_cur:
+ xfs_trans_brelse(tp, agbp);
+
+ return error;
+}
+
+/*
+ * Record a refcount intent for later processing.
+ */
+static int
+__xfs_refcount_add(
+ struct xfs_mount *mp,
+ struct xfs_defer_ops *dfops,
+ enum xfs_refcount_intent_type type,
+ xfs_fsblock_t startblock,
+ xfs_extlen_t blockcount)
+{
+ struct xfs_refcount_intent *ri;
+
+ trace_xfs_refcount_defer(mp, XFS_FSB_TO_AGNO(mp, startblock),
+ type, XFS_FSB_TO_AGBNO(mp, startblock),
+ blockcount);
+
+ ri = kmem_alloc(sizeof(struct xfs_refcount_intent),
+ KM_SLEEP | KM_NOFS);
+ INIT_LIST_HEAD(&ri->ri_list);
+ ri->ri_type = type;
+ ri->ri_startblock = startblock;
+ ri->ri_blockcount = blockcount;
+
+ xfs_defer_add(dfops, XFS_DEFER_OPS_TYPE_REFCOUNT, &ri->ri_list);
+ return 0;
+}
+
+/*
+ * Increase the reference count of the blocks backing a file's extent.
+ */
+int
+xfs_refcount_increase_extent(
+ struct xfs_mount *mp,
+ struct xfs_defer_ops *dfops,
+ struct xfs_bmbt_irec *PREV)
+{
+ if (!xfs_sb_version_hasreflink(&mp->m_sb))
+ return 0;
+
+ return __xfs_refcount_add(mp, dfops, XFS_REFCOUNT_INCREASE,
+ PREV->br_startblock, PREV->br_blockcount);
+}
+
+/*
+ * Decrease the reference count of the blocks backing a file's extent.
+ */
+int
+xfs_refcount_decrease_extent(
+ struct xfs_mount *mp,
+ struct xfs_defer_ops *dfops,
+ struct xfs_bmbt_irec *PREV)
+{
+ if (!xfs_sb_version_hasreflink(&mp->m_sb))
+ return 0;
+
+ return __xfs_refcount_add(mp, dfops, XFS_REFCOUNT_DECREASE,
+ PREV->br_startblock, PREV->br_blockcount);
+}
diff --git a/libxfs/xfs_refcount.h b/libxfs/xfs_refcount.h
index 2ef2b28..605d7d7 100644
--- a/libxfs/xfs_refcount.h
+++ b/libxfs/xfs_refcount.h
@@ -41,4 +41,16 @@ struct xfs_refcount_intent {
xfs_extlen_t ri_blockcount;
};
+extern int xfs_refcount_increase_extent(struct xfs_mount *mp,
+ struct xfs_defer_ops *dfops, struct xfs_bmbt_irec *irec);
+extern int xfs_refcount_decrease_extent(struct xfs_mount *mp,
+ struct xfs_defer_ops *dfops, struct xfs_bmbt_irec *irec);
+
+extern void xfs_refcount_finish_one_cleanup(struct xfs_trans *tp,
+ struct xfs_btree_cur *rcur, int error);
+extern int xfs_refcount_finish_one(struct xfs_trans *tp,
+ struct xfs_defer_ops *dfops, enum xfs_refcount_intent_type type,
+ xfs_fsblock_t startblock, xfs_extlen_t blockcount,
+ xfs_extlen_t *adjusted, struct xfs_btree_cur **pcur);
+
#endif /* __XFS_REFCOUNT_H__ */
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