@@ -38,6 +38,7 @@
#include "xfs_buf_item.h"
#include "xfs_log.h"
#include "xfs_ag_resv.h"
+#include "xfs_refcount_btree.h"
struct workqueue_struct *xfs_alloc_wq;
@@ -128,6 +129,8 @@ xfs_alloc_ag_max_usable(
blocks++; /* finobt root block */
if (xfs_sb_version_hasrmapbt(&mp->m_sb))
blocks++; /* rmap root block */
+ if (xfs_sb_version_hasreflink(&mp->m_sb))
+ blocks++; /* refcount root block */
return mp->m_sb.sb_agblocks - blocks;
}
@@ -381,3 +381,26 @@ xfs_refcountbt_compute_maxlevels(
mp->m_refc_maxlevels = xfs_btree_compute_maxlevels(mp,
mp->m_refc_mnr, mp->m_sb.sb_agblocks);
}
+
+/* Calculate the refcount btree size for some records. */
+xfs_extlen_t
+xfs_refcountbt_calc_size(
+ struct xfs_mount *mp,
+ unsigned long long len)
+{
+ return xfs_btree_calc_size(mp, mp->m_refc_mnr, len);
+}
+
+/*
+ * Calculate the maximum refcount btree size.
+ */
+xfs_extlen_t
+xfs_refcountbt_max_size(
+ struct xfs_mount *mp)
+{
+ /* Bail out if we're uninitialized, which can happen in mkfs. */
+ if (mp->m_refc_mxr[0] == 0)
+ return 0;
+
+ return xfs_refcountbt_calc_size(mp, mp->m_sb.sb_agblocks);
+}
@@ -64,4 +64,8 @@ extern int xfs_refcountbt_maxrecs(struct xfs_mount *mp, int blocklen,
bool leaf);
extern void xfs_refcountbt_compute_maxlevels(struct xfs_mount *mp);
+extern xfs_extlen_t xfs_refcountbt_calc_size(struct xfs_mount *mp,
+ unsigned long long len);
+extern xfs_extlen_t xfs_refcountbt_max_size(struct xfs_mount *mp);
+
#endif /* __XFS_REFCOUNT_BTREE_H__ */
The reference count btree is allocated from the free space, which means that we have to ensure that an AG can't run out of free space while performing a refcount operation. In the pathological case each AG block has its own refcntbt record, so we have to keep that much space available. v2: Calculate the maximum possible size of the rmap and refcount btrees based on minimally-full btree blocks. This increases the per-AG block reservations to handle the worst case btree size. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> --- fs/xfs/libxfs/xfs_alloc.c | 3 +++ fs/xfs/libxfs/xfs_refcount_btree.c | 23 +++++++++++++++++++++++ fs/xfs/libxfs/xfs_refcount_btree.h | 4 ++++ 3 files changed, 30 insertions(+)