xfs: flush speculative space allocations when we run out of quota

If a fs modification (creation, file write, reflink, etc.) is unable to
reserve enough quota to handle the modification, try clearing whatever
space the filesystem might have been hanging onto in the hopes of
speeding up the filesystem.  The flushing behavior will become
particularly important when we add deferred inode inactivation because
that will increase the amount of space that isn't actively tied to user
data.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>

10 files changed, 147 insertions, 9 deletions

diff --git a/fs/xfs/xfs_bmap_util.c b/fs/xfs/xfs_bmap_util.c
index 64bdee48fad4..f1f0b55fcd89 100644
--- a/fs/xfs/xfs_bmap_util.c
+++ b/fs/xfs/xfs_bmap_util.c
@@ -898,6 +898,7 @@ xfs_alloc_file_space(
 	 */
 	while (allocatesize_fsb && !error) {
 		xfs_fileoff_t	s, e;
+		bool		cleared_space = false;
 
 		/*
 		 * Determine space reservations for data/realtime.
@@ -940,6 +941,7 @@ xfs_alloc_file_space(
 		/*
 		 * Allocate and setup the transaction.
 		 */
+retry:
 		error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, resblks,
 				resrtextents, 0, &tp);
 
@@ -956,6 +958,20 @@ xfs_alloc_file_space(
 		xfs_ilock(ip, XFS_ILOCK_EXCL);
 		error = xfs_trans_reserve_quota_nblks(tp, ip, qblocks,
 						      0, quota_flag);
+		/*
+		 * We weren't able to reserve enough quota to handle fallocate.
+		 * Flush any disk space that was being held in the hopes of
+		 * speeding up the filesystem.  We hold the IOLOCK so we cannot
+		 * do a synchronous scan.
+		 */
+		if ((error == -ENOSPC || error == -EDQUOT) && !cleared_space) {
+			xfs_trans_cancel(tp);
+			xfs_iunlock(ip, XFS_ILOCK_EXCL);
+			cleared_space = xfs_inode_free_quota_blocks(ip, false);
+			if (cleared_space)
+				goto retry;
+			goto error2;
+		}
 		if (error)
 			goto error1;
 
@@ -994,6 +1010,7 @@ error0:	/* unlock inode, unreserve quota blocks, cancel trans */
 error1:	/* Just cancel transaction */
 	xfs_trans_cancel(tp);
 	xfs_iunlock(ip, XFS_ILOCK_EXCL);
+error2:
 	return error;
 }
 
diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
index f37e29b2055b..fd9dee4b58a3 100644
--- a/fs/xfs/xfs_file.c
+++ b/fs/xfs/xfs_file.c
@@ -649,7 +649,7 @@ write_retry:
 	 */
 	if (ret == -EDQUOT && !cleared_space) {
 		xfs_iunlock(ip, iolock);
-		cleared_space = xfs_inode_free_quota_blocks(ip);
+		cleared_space = xfs_inode_free_quota_blocks(ip, true);
 		if (cleared_space)
 			goto write_retry;
 		iolock = 0;
diff --git a/fs/xfs/xfs_icache.c b/fs/xfs/xfs_icache.c
index e18142922f55..6e4c3763d008 100644
--- a/fs/xfs/xfs_icache.c
+++ b/fs/xfs/xfs_icache.c
@@ -1532,7 +1532,8 @@ xfs_icache_free_eofblocks(
  */
 bool
 xfs_inode_free_quota_blocks(
-	struct xfs_inode	*ip)
+	struct xfs_inode	*ip,
+	bool			sync)
 {
 	struct xfs_eofblocks	eofb = {0};
 	struct xfs_dquot	*dq;
@@ -1542,7 +1543,9 @@ xfs_inode_free_quota_blocks(
 	 * Run a sync scan to increase effectiveness and use the union filter to
 	 * cover all applicable quotas in a single scan.
 	 */
-	eofb.eof_flags = XFS_EOF_FLAGS_UNION | XFS_EOF_FLAGS_SYNC;
+	eofb.eof_flags = XFS_EOF_FLAGS_UNION;
+	if (sync)
+		eofb.eof_flags |= XFS_EOF_FLAGS_SYNC;
 
 	if (XFS_IS_UQUOTA_ENFORCED(ip->i_mount)) {
 		dq = xfs_inode_dquot(ip, XFS_DQ_USER);
@@ -1574,6 +1577,8 @@ xfs_inode_free_quota_blocks(
 	if (!do_work)
 		return false;
 
+	trace_xfs_inode_free_quota_blocks(ip->i_mount, &eofb, _RET_IP_);
+
 	xfs_icache_free_eofblocks(ip->i_mount, &eofb);
 	xfs_icache_free_cowblocks(ip->i_mount, &eofb);
 	return true;
diff --git a/fs/xfs/xfs_icache.h b/fs/xfs/xfs_icache.h
index aaf44e841bec..a42a682cec0b 100644
--- a/fs/xfs/xfs_icache.h
+++ b/fs/xfs/xfs_icache.h
@@ -57,7 +57,7 @@ long xfs_reclaim_inodes_nr(struct xfs_mount *mp, int nr_to_scan);
 
 void xfs_inode_set_reclaim_tag(struct xfs_inode *ip);
 
-bool xfs_inode_free_quota_blocks(struct xfs_inode *ip);
+bool xfs_inode_free_quota_blocks(struct xfs_inode *ip, bool sync);
 
 void xfs_inode_set_eofblocks_tag(struct xfs_inode *ip);
 void xfs_inode_clear_eofblocks_tag(struct xfs_inode *ip);
diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c
index 4a7b0ea22fa3..dff7b1cd8424 100644
--- a/fs/xfs/xfs_inode.c
+++ b/fs/xfs/xfs_inode.c
@@ -1135,6 +1135,7 @@ xfs_create(
 	struct xfs_dquot	*gdqp = NULL;
 	struct xfs_dquot	*pdqp = NULL;
 	struct xfs_trans_res	*tres;
+	bool			cleared_space = false;
 	uint			resblks;
 
 	trace_xfs_create(dp, name);
@@ -1168,6 +1169,7 @@ xfs_create(
 	 * the case we'll drop the one we have and get a more
 	 * appropriate transaction later.
 	 */
+retry:
 	error = xfs_trans_alloc(mp, tres, resblks, 0, 0, &tp);
 	if (error == -ENOSPC) {
 		/* flush outstanding delalloc blocks and retry */
@@ -1185,6 +1187,21 @@ xfs_create(
 	 */
 	error = xfs_trans_reserve_quota(tp, mp, udqp, gdqp,
 						pdqp, resblks, 1, 0);
+	/*
+	 * We weren't able to reserve enough quota to handle adding the inode.
+	 * Flush any disk space that was being held in the hopes of speeding up
+	 * the filesystem.
+	 */
+	if ((error == -EDQUOT || error == -ENOSPC) && !cleared_space) {
+		xfs_trans_cancel(tp);
+		if (unlock_dp_on_error)
+			xfs_iunlock(dp, XFS_ILOCK_EXCL);
+		unlock_dp_on_error = false;
+		cleared_space = xfs_inode_free_quota_blocks(dp, true);
+		if (cleared_space)
+			goto retry;
+		goto out_release_inode;
+	}
 	if (error)
 		goto out_trans_cancel;
 
diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c
index e041ed404acc..0a4c4c73d3a6 100644
--- a/fs/xfs/xfs_ioctl.c
+++ b/fs/xfs/xfs_ioctl.c
@@ -2431,6 +2431,8 @@ xfs_file_ioctl(
 		if (error)
 			return error;
 
+		trace_xfs_ioc_free_eofblocks(mp, &keofb, _RET_IP_);
+
 		return xfs_icache_free_eofblocks(mp, &keofb);
 	}
 
diff --git a/fs/xfs/xfs_iomap.c b/fs/xfs/xfs_iomap.c
index 3a4310d7cb59..58b3ec6b00e3 100644
--- a/fs/xfs/xfs_iomap.c
+++ b/fs/xfs/xfs_iomap.c
@@ -27,7 +27,7 @@
 #include "xfs_dquot_item.h"
 #include "xfs_dquot.h"
 #include "xfs_reflink.h"
-
+#include "xfs_icache.h"
 
 #define XFS_WRITEIO_ALIGN(mp,off)	(((off) >> mp->m_writeio_log) \
 						<< mp->m_writeio_log)
@@ -185,6 +185,7 @@ xfs_iomap_write_direct(
 	int		error;
 	int		lockmode;
 	int		bmapi_flags = XFS_BMAPI_PREALLOC;
+	bool		cleared_space = false;
 	uint		tflags = 0;
 
 	rt = XFS_IS_REALTIME_INODE(ip);
@@ -258,6 +259,7 @@ xfs_iomap_write_direct(
 			resblks = XFS_DIOSTRAT_SPACE_RES(mp, 0) << 1;
 		}
 	}
+retry:
 	error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, resblks, resrtextents,
 			tflags, &tp);
 	if (error)
@@ -267,6 +269,23 @@ xfs_iomap_write_direct(
 	xfs_ilock(ip, lockmode);
 
 	error = xfs_trans_reserve_quota_nblks(tp, ip, qblocks, 0, quota_flag);
+	/*
+	 * We weren't able to reserve enough quota for the direct write.
+	 * Flush any disk space that was being held in the hopes of speeding up
+	 * the filesystem.  Historically, we expected callers to have
+	 * preallocated all the space before a direct write, but this is not an
+	 * absolute requirement.  We still hold the IOLOCK so we cannot do a
+	 * sync scan.
+	 */
+	if ((error == -ENOSPC || error == -EDQUOT) && !cleared_space) {
+		xfs_trans_cancel(tp);
+		xfs_iunlock(ip, lockmode);
+		lockmode = 0;
+		cleared_space = xfs_inode_free_quota_blocks(ip, false);
+		if (cleared_space)
+			goto retry;
+		goto out_unlock;
+	}
 	if (error)
 		goto out_trans_cancel;
 
diff --git a/fs/xfs/xfs_reflink.c b/fs/xfs/xfs_reflink.c
index c4ec7afd1170..17b6a67240a4 100644
--- a/fs/xfs/xfs_reflink.c
+++ b/fs/xfs/xfs_reflink.c
@@ -353,13 +353,14 @@ xfs_reflink_allocate_cow(
 	bool			convert_now)
 {
 	struct xfs_mount	*mp = ip->i_mount;
+	struct xfs_trans	*tp;
 	xfs_fileoff_t		offset_fsb = imap->br_startoff;
 	xfs_filblks_t		count_fsb = imap->br_blockcount;
-	struct xfs_trans	*tp;
-	int			nimaps, error = 0;
-	bool			found;
 	xfs_filblks_t		resaligned;
 	xfs_extlen_t		resblks = 0;
+	bool			found;
+	bool			cleared_space = false;
+	int			nimaps, error = 0;
 
 	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
 	if (!ip->i_cowfp) {
@@ -378,6 +379,7 @@ xfs_reflink_allocate_cow(
 	resblks = XFS_DIOSTRAT_SPACE_RES(mp, resaligned);
 
 	xfs_iunlock(ip, *lockmode);
+retry:
 	error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, resblks, 0, 0, &tp);
 	*lockmode = XFS_ILOCK_EXCL;
 	xfs_ilock(ip, *lockmode);
@@ -402,6 +404,23 @@ xfs_reflink_allocate_cow(
 
 	error = xfs_trans_reserve_quota_nblks(tp, ip, resblks, 0,
 			XFS_QMOPT_RES_REGBLKS);
+	/*
+	 * We weren't able to reserve enough quota to handle copy on write.
+	 * Flush any disk space that was being held in the hopes of speeding up
+	 * the filesystem.  We potentially hold the IOLOCK so we cannot do a
+	 * synchronous scan.
+	 */
+	if ((error == -ENOSPC || error == -EDQUOT) && !cleared_space) {
+		xfs_trans_cancel(tp);
+		xfs_iunlock(ip, *lockmode);
+		*lockmode = 0;
+		cleared_space = xfs_inode_free_quota_blocks(ip, false);
+		if (cleared_space)
+			goto retry;
+		*lockmode = XFS_ILOCK_EXCL;
+		xfs_ilock(ip, *lockmode);
+		goto out;
+	}
 	if (error)
 		goto out_trans_cancel;
 
@@ -443,6 +462,7 @@ out_unreserve:
 			XFS_QMOPT_RES_REGBLKS);
 out_trans_cancel:
 	xfs_trans_cancel(tp);
+out:
 	return error;
 }
 
@@ -1012,6 +1032,7 @@ xfs_reflink_remap_extent(
 	xfs_filblks_t		rlen;
 	xfs_filblks_t		unmap_len;
 	xfs_off_t		newlen;
+	bool			cleared_space = false;
 	int			error;
 
 	unmap_len = irec->br_startoff + irec->br_blockcount - destoff;
@@ -1027,21 +1048,37 @@ xfs_reflink_remap_extent(
 
 	/* Start a rolling transaction to switch the mappings */
 	resblks = XFS_EXTENTADD_SPACE_RES(ip->i_mount, XFS_DATA_FORK);
+retry:
 	error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, resblks, 0, 0, &tp);
 	if (error)
 		goto out;
 
 	xfs_ilock(ip, XFS_ILOCK_EXCL);
-	xfs_trans_ijoin(tp, ip, 0);
 
 	/* If we're not just clearing space, then do we have enough quota? */
 	if (real_extent) {
 		error = xfs_trans_reserve_quota_nblks(tp, ip,
 				irec->br_blockcount, 0, XFS_QMOPT_RES_REGBLKS);
+		/*
+		 * We weren't able to reserve enough quota for the remapping.
+		 * Flush any disk space that was being held in the hopes of
+		 * speeding up the filesystem.  We still hold the IOLOCK so we
+		 * cannot do a sync scan.
+		 */
+		if ((error == -ENOSPC || error == -EDQUOT) && !cleared_space) {
+			xfs_trans_cancel(tp);
+			xfs_iunlock(ip, XFS_ILOCK_EXCL);
+			cleared_space = xfs_inode_free_quota_blocks(ip, false);
+			if (cleared_space)
+				goto retry;
+			goto out;
+		}
 		if (error)
 			goto out_cancel;
 	}
 
+	xfs_trans_ijoin(tp, ip, 0);
+
 	trace_xfs_reflink_remap(ip, irec->br_startoff,
 				irec->br_blockcount, irec->br_startblock);
 
diff --git a/fs/xfs/xfs_trace.c b/fs/xfs/xfs_trace.c
index bc85b89f88ca..a39867a2686b 100644
--- a/fs/xfs/xfs_trace.c
+++ b/fs/xfs/xfs_trace.c
@@ -27,6 +27,7 @@
 #include "xfs_log_recover.h"
 #include "xfs_filestream.h"
 #include "xfs_fsmap.h"
+#include "xfs_icache.h"
 
 /*
  * We include this last to have the helpers above available for the trace
diff --git a/fs/xfs/xfs_trace.h b/fs/xfs/xfs_trace.h
index 8533ef64fc05..832c21a68418 100644
--- a/fs/xfs/xfs_trace.h
+++ b/fs/xfs/xfs_trace.h
@@ -30,6 +30,7 @@ struct xfs_btree_cur;
 struct xfs_refcount_irec;
 struct xfs_fsmap;
 struct xfs_rmap_irec;
+struct xfs_eofblocks;
 
 DECLARE_EVENT_CLASS(xfs_attr_list_class,
 	TP_PROTO(struct xfs_attr_list_context *ctx),
@@ -3603,6 +3604,45 @@ TRACE_EVENT(xfs_btree_commit_afakeroot,
                   __entry->agbno)
 )
 
+DECLARE_EVENT_CLASS(xfs_eofblocks_class,
+	TP_PROTO(struct xfs_mount *mp, struct xfs_eofblocks *eofb,
+		 unsigned long caller_ip),
+	TP_ARGS(mp, eofb, caller_ip),
+	TP_STRUCT__entry(
+		__field(dev_t, dev)
+		__field(__u32, flags)
+		__field(uint32_t, uid)
+		__field(uint32_t, gid)
+		__field(prid_t, prid)
+		__field(__u64, min_file_size)
+		__field(unsigned long, caller_ip)
+	),
+	TP_fast_assign(
+		__entry->dev = mp->m_super->s_dev;
+                __entry->flags = eofb->eof_flags;
+                __entry->uid = xfs_kuid_to_uid(eofb->eof_uid);
+                __entry->gid = xfs_kgid_to_gid(eofb->eof_gid);
+                __entry->prid = eofb->eof_prid;
+                __entry->min_file_size = eofb->eof_min_file_size;
+		__entry->caller_ip = caller_ip;
+	),
+	TP_printk("dev %d:%d flags 0x%x uid %u gid %u prid %u minsize %llu caller %pS",
+		  MAJOR(__entry->dev), MINOR(__entry->dev),
+                  __entry->flags,
+                  __entry->uid,
+                  __entry->gid,
+                  __entry->prid,
+                  __entry->min_file_size,
+		  (char *)__entry->caller_ip)
+);
+#define DEFINE_EOFBLOCKS_EVENT(name)	\
+DEFINE_EVENT(xfs_eofblocks_class, name,	\
+	TP_PROTO(struct xfs_mount *mp, struct xfs_eofblocks *eofb, \
+		 unsigned long caller_ip), \
+	TP_ARGS(mp, eofb, caller_ip))
+DEFINE_EOFBLOCKS_EVENT(xfs_ioc_free_eofblocks);
+DEFINE_EOFBLOCKS_EVENT(xfs_inode_free_quota_blocks);
+
 #endif /* _TRACE_XFS_H */
 
 #undef TRACE_INCLUDE_PATH