4 files changed, 57 insertions, 7 deletions

diff --git a/fs/xfs/xfs_dquot.c b/fs/xfs/xfs_dquot.c
index 9c5869e60f97..45bb08f6ba17 100644
--- a/fs/xfs/xfs_dquot.c
+++ b/fs/xfs/xfs_dquot.c
@@ -90,13 +90,18 @@ xfs_qm_adjust_dqlimits(
 {
 	struct xfs_quotainfo	*q = mp->m_quotainfo;
 	struct xfs_disk_dquot	*d = &dq->q_core;
+	int			prealloc = 0;
 
 	ASSERT(d->d_id);
 
-	if (q->qi_bsoftlimit && !d->d_blk_softlimit)
+	if (q->qi_bsoftlimit && !d->d_blk_softlimit) {
 		d->d_blk_softlimit = cpu_to_be64(q->qi_bsoftlimit);
-	if (q->qi_bhardlimit && !d->d_blk_hardlimit)
+		prealloc = 1;
+	}
+	if (q->qi_bhardlimit && !d->d_blk_hardlimit) {
 		d->d_blk_hardlimit = cpu_to_be64(q->qi_bhardlimit);
+		prealloc = 1;
+	}
 	if (q->qi_isoftlimit && !d->d_ino_softlimit)
 		d->d_ino_softlimit = cpu_to_be64(q->qi_isoftlimit);
 	if (q->qi_ihardlimit && !d->d_ino_hardlimit)
@@ -105,6 +110,9 @@ xfs_qm_adjust_dqlimits(
 		d->d_rtb_softlimit = cpu_to_be64(q->qi_rtbsoftlimit);
 	if (q->qi_rtbhardlimit && !d->d_rtb_hardlimit)
 		d->d_rtb_hardlimit = cpu_to_be64(q->qi_rtbhardlimit);
+
+	if (prealloc)
+		xfs_dquot_set_prealloc_limits(dq);
 }
 
 /*
@@ -249,6 +257,32 @@ xfs_qm_init_dquot_blk(
 	xfs_trans_log_buf(tp, bp, 0, BBTOB(q->qi_dqchunklen) - 1);
 }
 
+/*
+ * Initialize the dynamic speculative preallocation thresholds. The lo/hi
+ * watermarks correspond to the soft and hard limits by default. If a soft limit
+ * is not specified, we use 95% of the hard limit.
+ */
+void
+xfs_dquot_set_prealloc_limits(struct xfs_dquot *dqp)
+{
+	__uint64_t space;
+
+	dqp->q_prealloc_hi_wmark = be64_to_cpu(dqp->q_core.d_blk_hardlimit);
+	dqp->q_prealloc_lo_wmark = be64_to_cpu(dqp->q_core.d_blk_softlimit);
+	if (!dqp->q_prealloc_lo_wmark) {
+		dqp->q_prealloc_lo_wmark = dqp->q_prealloc_hi_wmark;
+		do_div(dqp->q_prealloc_lo_wmark, 100);
+		dqp->q_prealloc_lo_wmark *= 95;
+	}
+
+	space = dqp->q_prealloc_hi_wmark;
+
+	do_div(space, 100);
+	dqp->q_low_space[XFS_QLOWSP_1_PCNT] = space;
+	dqp->q_low_space[XFS_QLOWSP_3_PCNT] = space * 3;
+	dqp->q_low_space[XFS_QLOWSP_5_PCNT] = space * 5;
+}
+
 static void
 xfs_dquot_buf_verify(
 	struct xfs_buf		*bp)
@@ -649,6 +683,9 @@ xfs_qm_dqread(
 	dqp->q_res_icount = be64_to_cpu(ddqp->d_icount);
 	dqp->q_res_rtbcount = be64_to_cpu(ddqp->d_rtbcount);
 
+	/* initialize the dquot speculative prealloc thresholds */
+	xfs_dquot_set_prealloc_limits(dqp);
+
 	/* Mark the buf so that this will stay incore a little longer */
 	xfs_buf_set_ref(bp, XFS_DQUOT_REF);
 
diff --git a/fs/xfs/xfs_dquot.h b/fs/xfs/xfs_dquot.h
index f77b711455b1..4f0ebfc43cc9 100644
--- a/fs/xfs/xfs_dquot.h
+++ b/fs/xfs/xfs_dquot.h
@@ -32,6 +32,13 @@
 struct xfs_mount;
 struct xfs_trans;
 
+enum {
+	XFS_QLOWSP_1_PCNT = 0,
+	XFS_QLOWSP_3_PCNT,
+	XFS_QLOWSP_5_PCNT,
+	XFS_QLOWSP_MAX
+};
+
 /*
  * The incore dquot structure
  */
@@ -51,6 +58,9 @@ typedef struct xfs_dquot {
 	xfs_qcnt_t	 q_res_bcount;	/* total regular nblks used+reserved */
 	xfs_qcnt_t	 q_res_icount;	/* total inos allocd+reserved */
 	xfs_qcnt_t	 q_res_rtbcount;/* total realtime blks used+reserved */
+	xfs_qcnt_t	 q_prealloc_lo_wmark;/* prealloc throttle wmark */
+	xfs_qcnt_t	 q_prealloc_hi_wmark;/* prealloc disabled wmark */
+	int64_t		 q_low_space[XFS_QLOWSP_MAX];
 	struct mutex	 q_qlock;	/* quota lock */
 	struct completion q_flush;	/* flush completion queue */
 	atomic_t          q_pincount;	/* dquot pin count */
@@ -153,6 +163,8 @@ extern void		xfs_qm_dqput(xfs_dquot_t *);
 
 extern void		xfs_dqlock2(struct xfs_dquot *, struct xfs_dquot *);
 
+extern void		xfs_dquot_set_prealloc_limits(struct xfs_dquot *);
+
 static inline struct xfs_dquot *xfs_qm_dqhold(struct xfs_dquot *dqp)
 {
 	xfs_dqlock(dqp);
diff --git a/fs/xfs/xfs_qm.h b/fs/xfs/xfs_qm.h
index 44b858b79d71..82c21084587b 100644
--- a/fs/xfs/xfs_qm.h
+++ b/fs/xfs/xfs_qm.h
@@ -116,7 +116,7 @@ extern void		xfs_qm_dqrele_all_inodes(xfs_mount_t *, uint);
 extern int		xfs_qm_scall_trunc_qfiles(xfs_mount_t *, uint);
 extern int		xfs_qm_scall_getquota(xfs_mount_t *, xfs_dqid_t, uint,
 					fs_disk_quota_t *);
-extern int		xfs_qm_scall_setqlim(xfs_mount_t *, xfs_dqid_t, uint,
+extern int		xfs_qm_scall_setqlim(struct xfs_mount *, xfs_dqid_t, uint,
 					fs_disk_quota_t *);
 extern int		xfs_qm_scall_getqstat(xfs_mount_t *, fs_quota_stat_t *);
 extern int		xfs_qm_scall_quotaon(xfs_mount_t *, uint);
diff --git a/fs/xfs/xfs_qm_syscalls.c b/fs/xfs/xfs_qm_syscalls.c
index cf9a34051e07..c41190cad6e9 100644
--- a/fs/xfs/xfs_qm_syscalls.c
+++ b/fs/xfs/xfs_qm_syscalls.c
@@ -472,15 +472,15 @@ xfs_qm_scall_getqstat(
  */
 int
 xfs_qm_scall_setqlim(
-	xfs_mount_t		*mp,
+	struct xfs_mount	*mp,
 	xfs_dqid_t		id,
 	uint			type,
 	fs_disk_quota_t		*newlim)
 {
 	struct xfs_quotainfo	*q = mp->m_quotainfo;
-	xfs_disk_dquot_t	*ddq;
-	xfs_dquot_t		*dqp;
-	xfs_trans_t		*tp;
+	struct xfs_disk_dquot	*ddq;
+	struct xfs_dquot	*dqp;
+	struct xfs_trans	*tp;
 	int			error;
 	xfs_qcnt_t		hard, soft;
 
@@ -529,6 +529,7 @@ xfs_qm_scall_setqlim(
 	if (hard == 0 || hard >= soft) {
 		ddq->d_blk_hardlimit = cpu_to_be64(hard);
 		ddq->d_blk_softlimit = cpu_to_be64(soft);
+		xfs_dquot_set_prealloc_limits(dqp);
 		if (id == 0) {
 			q->qi_bhardlimit = hard;
 			q->qi_bsoftlimit = soft;