1 files changed, 135 insertions, 92 deletions

diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c
index 70bf706b1090..ba1246433794 100644
--- a/fs/nfs/pnfs.c
+++ b/fs/nfs/pnfs.c
@@ -368,7 +368,6 @@ pnfs_prepare_layoutreturn(struct pnfs_layout_hdr *lo)
 	if (test_and_set_bit(NFS_LAYOUT_RETURN, &lo->plh_flags))
 		return false;
 	lo->plh_return_iomode = 0;
-	lo->plh_block_lgets++;
 	pnfs_get_layout_hdr(lo);
 	clear_bit(NFS_LAYOUT_RETURN_BEFORE_CLOSE, &lo->plh_flags);
 	return true;
@@ -817,25 +816,12 @@ pnfs_layout_stateid_blocked(const struct pnfs_layout_hdr *lo,
 	return !pnfs_seqid_is_newer(seqid, lo->plh_barrier);
 }
 
-static bool
-pnfs_layout_returning(const struct pnfs_layout_hdr *lo,
-		      struct pnfs_layout_range *range)
-{
-	return test_bit(NFS_LAYOUT_RETURN, &lo->plh_flags) &&
-		(lo->plh_return_iomode == IOMODE_ANY ||
-		 lo->plh_return_iomode == range->iomode);
-}
-
 /* lget is set to 1 if called from inside send_layoutget call chain */
 static bool
-pnfs_layoutgets_blocked(const struct pnfs_layout_hdr *lo,
-			struct pnfs_layout_range *range, int lget)
+pnfs_layoutgets_blocked(const struct pnfs_layout_hdr *lo)
 {
 	return lo->plh_block_lgets ||
-		test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags) ||
-		(list_empty(&lo->plh_segs) &&
-		 (atomic_read(&lo->plh_outstanding) > lget)) ||
-		pnfs_layout_returning(lo, range);
+		test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags);
 }
 
 int
@@ -847,7 +833,7 @@ pnfs_choose_layoutget_stateid(nfs4_stateid *dst, struct pnfs_layout_hdr *lo,
 
 	dprintk("--> %s\n", __func__);
 	spin_lock(&lo->plh_inode->i_lock);
-	if (pnfs_layoutgets_blocked(lo, range, 1)) {
+	if (pnfs_layoutgets_blocked(lo)) {
 		status = -EAGAIN;
 	} else if (!nfs4_valid_open_stateid(open_state)) {
 		status = -EBADF;
@@ -882,6 +868,7 @@ send_layoutget(struct pnfs_layout_hdr *lo,
 	struct nfs_server *server = NFS_SERVER(ino);
 	struct nfs4_layoutget *lgp;
 	struct pnfs_layout_segment *lseg;
+	loff_t i_size;
 
 	dprintk("--> %s\n", __func__);
 
@@ -889,9 +876,17 @@ send_layoutget(struct pnfs_layout_hdr *lo,
 	if (lgp == NULL)
 		return NULL;
 
+	i_size = i_size_read(ino);
+
 	lgp->args.minlength = PAGE_CACHE_SIZE;
 	if (lgp->args.minlength > range->length)
 		lgp->args.minlength = range->length;
+	if (range->iomode == IOMODE_READ) {
+		if (range->offset >= i_size)
+			lgp->args.minlength = 0;
+		else if (i_size - range->offset < lgp->args.minlength)
+			lgp->args.minlength = i_size - range->offset;
+	}
 	lgp->args.maxcount = PNFS_LAYOUT_MAXSIZE;
 	lgp->args.range = *range;
 	lgp->args.type = server->pnfs_curr_ld->id;
@@ -956,9 +951,7 @@ pnfs_send_layoutreturn(struct pnfs_layout_hdr *lo, nfs4_stateid stateid,
 	if (unlikely(lrp == NULL)) {
 		status = -ENOMEM;
 		spin_lock(&ino->i_lock);
-		lo->plh_block_lgets--;
 		pnfs_clear_layoutreturn_waitbit(lo);
-		rpc_wake_up(&NFS_SERVER(ino)->roc_rpcwaitq);
 		spin_unlock(&ino->i_lock);
 		pnfs_put_layout_hdr(lo);
 		goto out;
@@ -1080,15 +1073,14 @@ bool pnfs_roc(struct inode *ino)
 	struct pnfs_layout_segment *lseg, *tmp;
 	nfs4_stateid stateid;
 	LIST_HEAD(tmp_list);
-	bool found = false, layoutreturn = false;
+	bool found = false, layoutreturn = false, roc = false;
 
 	spin_lock(&ino->i_lock);
 	lo = nfsi->layout;
-	if (!lo || !test_and_clear_bit(NFS_LAYOUT_ROC, &lo->plh_flags) ||
-	    test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags))
+	if (!lo || test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags))
 		goto out_noroc;
 
-	/* Don't return layout if we hold a delegation */
+	/* no roc if we hold a delegation */
 	if (nfs4_check_delegation(ino, FMODE_READ))
 		goto out_noroc;
 
@@ -1099,34 +1091,41 @@ bool pnfs_roc(struct inode *ino)
 			goto out_noroc;
 	}
 
+	stateid = lo->plh_stateid;
+	/* always send layoutreturn if being marked so */
+	if (test_and_clear_bit(NFS_LAYOUT_RETURN_BEFORE_CLOSE,
+				   &lo->plh_flags))
+		layoutreturn = pnfs_prepare_layoutreturn(lo);
+
 	pnfs_clear_retry_layoutget(lo);
 	list_for_each_entry_safe(lseg, tmp, &lo->plh_segs, pls_list)
-		if (test_bit(NFS_LSEG_ROC, &lseg->pls_flags)) {
+		/* If we are sending layoutreturn, invalidate all valid lsegs */
+		if (layoutreturn || test_bit(NFS_LSEG_ROC, &lseg->pls_flags)) {
 			mark_lseg_invalid(lseg, &tmp_list);
 			found = true;
 		}
-	if (!found)
-		goto out_noroc;
-	lo->plh_block_lgets++;
-	pnfs_get_layout_hdr(lo); /* matched in pnfs_roc_release */
-	spin_unlock(&ino->i_lock);
-	pnfs_free_lseg_list(&tmp_list);
-	pnfs_layoutcommit_inode(ino, true);
-	return true;
+	/* pnfs_prepare_layoutreturn() grabs lo ref and it will be put
+	 * in pnfs_roc_release(). We don't really send a layoutreturn but
+	 * still want others to view us like we are sending one!
+	 *
+	 * If pnfs_prepare_layoutreturn() fails, it means someone else is doing
+	 * LAYOUTRETURN, so we proceed like there are no layouts to return.
+	 *
+	 * ROC in three conditions:
+	 * 1. there are ROC lsegs
+	 * 2. we don't send layoutreturn
+	 * 3. no others are sending layoutreturn
+	 */
+	if (found && !layoutreturn && pnfs_prepare_layoutreturn(lo))
+		roc = true;
 
 out_noroc:
-	if (lo) {
-		stateid = lo->plh_stateid;
-		if (test_and_clear_bit(NFS_LAYOUT_RETURN_BEFORE_CLOSE,
-					   &lo->plh_flags))
-			layoutreturn = pnfs_prepare_layoutreturn(lo);
-	}
 	spin_unlock(&ino->i_lock);
-	if (layoutreturn) {
-		pnfs_layoutcommit_inode(ino, true);
+	pnfs_free_lseg_list(&tmp_list);
+	pnfs_layoutcommit_inode(ino, true);
+	if (layoutreturn)
 		pnfs_send_layoutreturn(lo, stateid, IOMODE_ANY, true);
-	}
-	return false;
+	return roc;
 }
 
 void pnfs_roc_release(struct inode *ino)
@@ -1135,7 +1134,7 @@ void pnfs_roc_release(struct inode *ino)
 
 	spin_lock(&ino->i_lock);
 	lo = NFS_I(ino)->layout;
-	lo->plh_block_lgets--;
+	pnfs_clear_layoutreturn_waitbit(lo);
 	if (atomic_dec_and_test(&lo->plh_refcount)) {
 		pnfs_detach_layout_hdr(lo);
 		spin_unlock(&ino->i_lock);
@@ -1153,27 +1152,16 @@ void pnfs_roc_set_barrier(struct inode *ino, u32 barrier)
 	if (pnfs_seqid_is_newer(barrier, lo->plh_barrier))
 		lo->plh_barrier = barrier;
 	spin_unlock(&ino->i_lock);
+	trace_nfs4_layoutreturn_on_close(ino, 0);
 }
 
-bool pnfs_roc_drain(struct inode *ino, u32 *barrier, struct rpc_task *task)
+void pnfs_roc_get_barrier(struct inode *ino, u32 *barrier)
 {
 	struct nfs_inode *nfsi = NFS_I(ino);
 	struct pnfs_layout_hdr *lo;
-	struct pnfs_layout_segment *lseg;
-	nfs4_stateid stateid;
 	u32 current_seqid;
-	bool layoutreturn = false;
 
 	spin_lock(&ino->i_lock);
-	list_for_each_entry(lseg, &nfsi->layout->plh_segs, pls_list) {
-		if (!test_bit(NFS_LSEG_ROC, &lseg->pls_flags))
-			continue;
-		if (test_bit(NFS_LSEG_VALID, &lseg->pls_flags))
-			continue;
-		rpc_sleep_on(&NFS_SERVER(ino)->roc_rpcwaitq, task, NULL);
-		spin_unlock(&ino->i_lock);
-		return true;
-	}
 	lo = nfsi->layout;
 	current_seqid = be32_to_cpu(lo->plh_stateid.seqid);
 
@@ -1181,19 +1169,7 @@ bool pnfs_roc_drain(struct inode *ino, u32 *barrier, struct rpc_task *task)
 	 * a barrier, we choose the worst-case barrier.
 	 */
 	*barrier = current_seqid + atomic_read(&lo->plh_outstanding);
-	stateid = lo->plh_stateid;
-	if (test_and_clear_bit(NFS_LAYOUT_RETURN_BEFORE_CLOSE,
-					   &lo->plh_flags))
-		layoutreturn = pnfs_prepare_layoutreturn(lo);
-	if (test_bit(NFS_LAYOUT_RETURN, &lo->plh_flags))
-		rpc_sleep_on(&NFS_SERVER(ino)->roc_rpcwaitq, task, NULL);
-
 	spin_unlock(&ino->i_lock);
-	if (layoutreturn) {
-		pnfs_send_layoutreturn(lo, stateid, IOMODE_ANY, false);
-		return true;
-	}
-	return false;
 }
 
 /*
@@ -1221,16 +1197,41 @@ pnfs_lseg_range_cmp(const struct pnfs_layout_range *l1,
 	return (int)(l1->iomode == IOMODE_READ) - (int)(l2->iomode == IOMODE_READ);
 }
 
-static void
-pnfs_layout_insert_lseg(struct pnfs_layout_hdr *lo,
-		   struct pnfs_layout_segment *lseg)
+static bool
+pnfs_lseg_range_is_after(const struct pnfs_layout_range *l1,
+		const struct pnfs_layout_range *l2)
 {
-	struct pnfs_layout_segment *lp;
+	return pnfs_lseg_range_cmp(l1, l2) > 0;
+}
+
+static bool
+pnfs_lseg_no_merge(struct pnfs_layout_segment *lseg,
+		struct pnfs_layout_segment *old)
+{
+	return false;
+}
+
+void
+pnfs_generic_layout_insert_lseg(struct pnfs_layout_hdr *lo,
+		   struct pnfs_layout_segment *lseg,
+		   bool (*is_after)(const struct pnfs_layout_range *,
+			   const struct pnfs_layout_range *),
+		   bool (*do_merge)(struct pnfs_layout_segment *,
+			   struct pnfs_layout_segment *),
+		   struct list_head *free_me)
+{
+	struct pnfs_layout_segment *lp, *tmp;
 
 	dprintk("%s:Begin\n", __func__);
 
-	list_for_each_entry(lp, &lo->plh_segs, pls_list) {
-		if (pnfs_lseg_range_cmp(&lseg->pls_range, &lp->pls_range) > 0)
+	list_for_each_entry_safe(lp, tmp, &lo->plh_segs, pls_list) {
+		if (test_bit(NFS_LSEG_VALID, &lp->pls_flags) == 0)
+			continue;
+		if (do_merge(lseg, lp)) {
+			mark_lseg_invalid(lp, free_me);
+			continue;
+		}
+		if (is_after(&lseg->pls_range, &lp->pls_range))
 			continue;
 		list_add_tail(&lseg->pls_list, &lp->pls_list);
 		dprintk("%s: inserted lseg %p "
@@ -1252,6 +1253,24 @@ out:
 
 	dprintk("%s:Return\n", __func__);
 }
+EXPORT_SYMBOL_GPL(pnfs_generic_layout_insert_lseg);
+
+static void
+pnfs_layout_insert_lseg(struct pnfs_layout_hdr *lo,
+		   struct pnfs_layout_segment *lseg,
+		   struct list_head *free_me)
+{
+	struct inode *inode = lo->plh_inode;
+	struct pnfs_layoutdriver_type *ld = NFS_SERVER(inode)->pnfs_curr_ld;
+
+	if (ld->add_lseg != NULL)
+		ld->add_lseg(lo, lseg, free_me);
+	else
+		pnfs_generic_layout_insert_lseg(lo, lseg,
+				pnfs_lseg_range_is_after,
+				pnfs_lseg_no_merge,
+				free_me);
+}
 
 static struct pnfs_layout_hdr *
 alloc_init_layout_hdr(struct inode *ino,
@@ -1344,8 +1363,6 @@ pnfs_find_lseg(struct pnfs_layout_hdr *lo,
 			ret = pnfs_get_lseg(lseg);
 			break;
 		}
-		if (lseg->pls_range.offset > range->offset)
-			break;
 	}
 
 	dprintk("%s:Return lseg %p ref %d\n",
@@ -1438,6 +1455,8 @@ static int pnfs_layoutget_retry_bit_wait(struct wait_bit_key *key)
 
 static bool pnfs_prepare_to_retry_layoutget(struct pnfs_layout_hdr *lo)
 {
+	if (!pnfs_should_retry_layoutget(lo))
+		return false;
 	/*
 	 * send layoutcommit as it can hold up layoutreturn due to lseg
 	 * reference
@@ -1484,6 +1503,9 @@ pnfs_update_layout(struct inode *ino,
 	if (!pnfs_enabled_sb(NFS_SERVER(ino)))
 		goto out;
 
+	if (iomode == IOMODE_READ && i_size_read(ino) == 0)
+		goto out;
+
 	if (pnfs_within_mdsthreshold(ctx, ino, iomode))
 		goto out;
 
@@ -1533,8 +1555,7 @@ lookup_again:
 	 * Because we free lsegs before sending LAYOUTRETURN, we need to wait
 	 * for LAYOUTRETURN even if first is true.
 	 */
-	if (!lseg && pnfs_should_retry_layoutget(lo) &&
-	    test_bit(NFS_LAYOUT_RETURN, &lo->plh_flags)) {
+	if (test_bit(NFS_LAYOUT_RETURN, &lo->plh_flags)) {
 		spin_unlock(&ino->i_lock);
 		dprintk("%s wait for layoutreturn\n", __func__);
 		if (pnfs_prepare_to_retry_layoutget(lo)) {
@@ -1547,7 +1568,7 @@ lookup_again:
 		goto out_put_layout_hdr;
 	}
 
-	if (pnfs_layoutgets_blocked(lo, &arg, 0))
+	if (pnfs_layoutgets_blocked(lo))
 		goto out_unlock;
 	atomic_inc(&lo->plh_outstanding);
 	spin_unlock(&ino->i_lock);
@@ -1593,6 +1614,26 @@ out_unlock:
 }
 EXPORT_SYMBOL_GPL(pnfs_update_layout);
 
+static bool
+pnfs_sanity_check_layout_range(struct pnfs_layout_range *range)
+{
+	switch (range->iomode) {
+	case IOMODE_READ:
+	case IOMODE_RW:
+		break;
+	default:
+		return false;
+	}
+	if (range->offset == NFS4_MAX_UINT64)
+		return false;
+	if (range->length == 0)
+		return false;
+	if (range->length != NFS4_MAX_UINT64 &&
+	    range->length > NFS4_MAX_UINT64 - range->offset)
+		return false;
+	return true;
+}
+
 struct pnfs_layout_segment *
 pnfs_layout_process(struct nfs4_layoutget *lgp)
 {
@@ -1601,7 +1642,10 @@ pnfs_layout_process(struct nfs4_layoutget *lgp)
 	struct pnfs_layout_segment *lseg;
 	struct inode *ino = lo->plh_inode;
 	LIST_HEAD(free_me);
-	int status = 0;
+	int status = -EINVAL;
+
+	if (!pnfs_sanity_check_layout_range(&res->range))
+		goto out;
 
 	/* Inject layout blob into I/O device driver */
 	lseg = NFS_SERVER(ino)->pnfs_curr_ld->alloc_lseg(lo, res, lgp->gfp_flags);
@@ -1619,12 +1663,7 @@ pnfs_layout_process(struct nfs4_layoutget *lgp)
 	lseg->pls_range = res->range;
 
 	spin_lock(&ino->i_lock);
-	if (test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags)) {
-		dprintk("%s forget reply due to recall\n", __func__);
-		goto out_forget_reply;
-	}
-
-	if (pnfs_layoutgets_blocked(lo, &lgp->args.range, 1)) {
+	if (pnfs_layoutgets_blocked(lo)) {
 		dprintk("%s forget reply due to state\n", __func__);
 		goto out_forget_reply;
 	}
@@ -1651,12 +1690,10 @@ pnfs_layout_process(struct nfs4_layoutget *lgp)
 	clear_bit(NFS_LAYOUT_INVALID_STID, &lo->plh_flags);
 
 	pnfs_get_lseg(lseg);
-	pnfs_layout_insert_lseg(lo, lseg);
+	pnfs_layout_insert_lseg(lo, lseg, &free_me);
 
-	if (res->return_on_close) {
+	if (res->return_on_close)
 		set_bit(NFS_LSEG_ROC, &lseg->pls_flags);
-		set_bit(NFS_LAYOUT_ROC, &lo->plh_flags);
-	}
 
 	spin_unlock(&ino->i_lock);
 	pnfs_free_lseg_list(&free_me);
@@ -1692,6 +1729,8 @@ pnfs_mark_matching_lsegs_return(struct pnfs_layout_hdr *lo,
 				lseg->pls_range.length);
 			set_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags);
 			mark_lseg_invalid(lseg, tmp_list);
+			set_bit(NFS_LAYOUT_RETURN_BEFORE_CLOSE,
+					&lo->plh_flags);
 		}
 }
 
@@ -2267,7 +2306,7 @@ struct nfs4_threshold *pnfs_mdsthreshold_alloc(void)
 
 #if IS_ENABLED(CONFIG_NFS_V4_2)
 int
-pnfs_report_layoutstat(struct inode *inode)
+pnfs_report_layoutstat(struct inode *inode, gfp_t gfp_flags)
 {
 	struct pnfs_layoutdriver_type *ld = NFS_SERVER(inode)->pnfs_curr_ld;
 	struct nfs_server *server = NFS_SERVER(inode);
@@ -2294,7 +2333,7 @@ pnfs_report_layoutstat(struct inode *inode)
 	pnfs_get_layout_hdr(hdr);
 	spin_unlock(&inode->i_lock);
 
-	data = kzalloc(sizeof(*data), GFP_KERNEL);
+	data = kzalloc(sizeof(*data), gfp_flags);
 	if (!data) {
 		status = -ENOMEM;
 		goto out_put;
@@ -2324,3 +2363,7 @@ out_put:
 }
 EXPORT_SYMBOL_GPL(pnfs_report_layoutstat);
 #endif
+
+unsigned int layoutstats_timer;
+module_param(layoutstats_timer, uint, 0644);
+EXPORT_SYMBOL_GPL(layoutstats_timer);