#define XFS_ALLOC_FLAG_TRYLOCK 0x00000001 /* use trylock for buffer locking */
#define XFS_ALLOC_FLAG_FREEING 0x00000002 /* indicate caller is freeing extents*/
+/*
+ * In order to avoid ENOSPC-related deadlock caused by
+ * out-of-order locking of AGF buffer (PV 947395), we place
+ * constraints on the relationship among actual allocations for
+ * data blocks, freelist blocks, and potential file data bmap
+ * btree blocks. However, these restrictions may result in no
+ * actual space allocated for a delayed extent, for example, a data
+ * block in a certain AG is allocated but there is no additional
+ * block for the additional bmap btree block due to a split of the
+ * bmap btree of the file. The result of this may lead to an
+ * infinite loop in xfssyncd when the file gets flushed to disk and
+ * all delayed extents need to be actually allocated. To get around
+ * this, we explicitly set aside a few blocks which will not be
+ * reserved in delayed allocation. Considering the minimum number of
+ * needed freelist blocks is 4 fsbs _per AG_, a potential split of file's bmap
+ * btree requires 1 fsb, so we set the number of set-aside blocks
+ * to 4 + 4*agcount.
+ */
+#define XFS_ALLOC_SET_ASIDE(mp) (4 + ((mp)->m_sb.sb_agcount * 4))
+
/*
* Argument structure for xfs_alloc routines.
* This is turned into a structure to avoid having 20 arguments passed
#define XFS_ALLOC_KTRACE_BUSYSEARCH 6
#endif
+void
+xfs_alloc_mark_busy(xfs_trans_t *tp,
+ xfs_agnumber_t agno,
+ xfs_agblock_t bno,
+ xfs_extlen_t len);
+
+void
+xfs_alloc_clear_busy(xfs_trans_t *tp,
+ xfs_agnumber_t ag,
+ int idx);
+
+#endif /* __KERNEL__ */
+
/*
* Compute and fill in value of m_ag_maxlevels.
*/
xfs_alloc_get_freelist(
struct xfs_trans *tp, /* transaction pointer */
struct xfs_buf *agbp, /* buffer containing the agf structure */
- xfs_agblock_t *bnop); /* block address retrieved from freelist */
+ xfs_agblock_t *bnop, /* block address retrieved from freelist */
+ int btreeblk); /* destination is a AGF btree */
/*
* Log the given fields from the agf structure.
struct xfs_trans *tp, /* transaction pointer */
struct xfs_buf *agbp, /* buffer for a.g. freelist header */
struct xfs_buf *agflbp,/* buffer for a.g. free block array */
- xfs_agblock_t bno); /* block being freed */
+ xfs_agblock_t bno, /* block being freed */
+ int btreeblk); /* owner was a AGF btree */
/*
* Read in the allocation group header (free/alloc section).
xfs_fsblock_t bno, /* starting block number of extent */
xfs_extlen_t len); /* length of extent */
-void
-xfs_alloc_mark_busy(xfs_trans_t *tp,
- xfs_agnumber_t agno,
- xfs_agblock_t bno,
- xfs_extlen_t len);
-
-void
-xfs_alloc_clear_busy(xfs_trans_t *tp,
- xfs_agnumber_t ag,
- int idx);
-
-
-#endif /* __KERNEL__ */
-
#endif /* __XFS_ALLOC_H__ */