[PATCH 0/9] NFSv4/flexfiles: Add support for striped layouts

[PATCH 0/9] NFSv4/flexfiles: Add support for striped layouts

[Jonathan Curley]

This patch series introduces support for striped layouts:

The first 2 patches are simple preparation changes. There should be
no logical impact to the code.

The 3rd patch refactors the nfs4_ff_layout_mirror struct to have an
array of a new nfs4_ff_layout_ds_stripe type. The
nfs4_ff_layout_ds_stripe has all the contents of ff_data_server4 per
the flexfile rfc. I called it ds_stripe because ds was already taken
by the deviceid side of the code.

The patches 4-8 update various paths to be dss_id aware. Most of this
consists of either adding a new parameter to the function or adding a
loop. Depending on which is appropriate.

The final patch 9 updates the layout creation path to populate the
array and turns the feature on.

Jonathan Curley (9):
  NFSv4/flexfiles: Remove cred local variable dependency
  NFSv4/flexfiles: Use ds_commit_idx when marking a write commit
  NFSv4/flexfiles: Add data structure support for striped layouts
  NFSv4/flexfiles: Update low level helper functions to be DS stripe
    aware.
  NFSv4/flexfiles: Read path updates for striped layouts
  NFSv4/flexfiles: Commit path updates for striped layouts
  NFSv4/flexfiles: Write path updates for striped layouts
  NFSv4/flexfiles: Update layout stats & error paths for striped layouts
  NFSv4/flexfiles: Add support for striped layouts

 fs/nfs/flexfilelayout/flexfilelayout.c    | 774 +++++++++++++++-------
 fs/nfs/flexfilelayout/flexfilelayout.h    |  64 +-
 fs/nfs/flexfilelayout/flexfilelayoutdev.c | 110 +--
 fs/nfs/write.c                            |   2 +-
 4 files changed, 636 insertions(+), 314 deletions(-)

-- 
2.34.1

[PATCH 1/9] NFSv4/flexfiles: Remove cred local variable dependency

[Jonathan Curley]

No-op preparation change to remove dependency on cred local
variable. Subsequent striping diff has a cred per stripe so this local
variable can't be trusted to be the same.

Signed-off-by: Jonathan Curley <jcurley@purestorage.com>
---
 fs/nfs/flexfilelayout/flexfilelayout.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/fs/nfs/flexfilelayout/flexfilelayout.c b/fs/nfs/flexfilelayout/flexfilelayout.c
index 4bea008dbebd..a437d20ebcdf 100644
--- a/fs/nfs/flexfilelayout/flexfilelayout.c
+++ b/fs/nfs/flexfilelayout/flexfilelayout.c
@@ -532,10 +532,10 @@ ff_layout_alloc_lseg(struct pnfs_layout_hdr *lh,
 		if (mirror != fls->mirror_array[i]) {
 			/* swap cred ptrs so free_mirror will clean up old */
 			if (lgr->range.iomode == IOMODE_READ) {
-				cred = xchg(&mirror->ro_cred, cred);
+				cred = xchg(&mirror->ro_cred, fls->mirror_array[i]->ro_cred);
 				rcu_assign_pointer(fls->mirror_array[i]->ro_cred, cred);
 			} else {
-				cred = xchg(&mirror->rw_cred, cred);
+				cred = xchg(&mirror->rw_cred, fls->mirror_array[i]->rw_cred);
 				rcu_assign_pointer(fls->mirror_array[i]->rw_cred, cred);
 			}
 			ff_layout_free_mirror(fls->mirror_array[i]);
-- 
2.34.1

[PATCH 2/9] NFSv4/flexfiles: Use ds_commit_idx when marking a write commit

[Jonathan Curley]

Correct this path to use ds_commit_idx. Another noop preparation
change. In current code commit_idx == mirror_idx but when striping is
enabled that will not be true.

Signed-off-by: Jonathan Curley <jcurley@purestorage.com>
---
 fs/nfs/write.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/nfs/write.c b/fs/nfs/write.c
index 374fc6b34c79..422bb817cc85 100644
--- a/fs/nfs/write.c
+++ b/fs/nfs/write.c
@@ -977,7 +977,7 @@ static void nfs_write_completion(struct nfs_pgio_header *hdr)
 			req->wb_nio = 0;
 			memcpy(&req->wb_verf, &hdr->verf.verifier, sizeof(req->wb_verf));
 			nfs_mark_request_commit(req, hdr->lseg, &cinfo,
-				hdr->pgio_mirror_idx);
+				hdr->ds_commit_idx);
 			goto next;
 		}
 remove_req:
-- 
2.34.1

[PATCH 3/9] NFSv4/flexfiles: Add data structure support for striped layouts

[Jonathan Curley]

Adds a new struct nfs4_ff_layout_ds_stripe that represents a data
server stripe within a layout. A new dynamically allocated array of
this type has been added to nfs4_ff_layout_mirror and per stripe
configuration information has been moved from the mirror type to the
stripe based on the RFC.

Signed-off-by: Jonathan Curley <jcurley@purestorage.com>
---
 fs/nfs/flexfilelayout/flexfilelayout.c    | 134 ++++++++++++----------
 fs/nfs/flexfilelayout/flexfilelayout.h    |  27 +++--
 fs/nfs/flexfilelayout/flexfilelayoutdev.c |  54 ++++-----
 3 files changed, 117 insertions(+), 98 deletions(-)

diff --git a/fs/nfs/flexfilelayout/flexfilelayout.c b/fs/nfs/flexfilelayout/flexfilelayout.c
index a437d20ebcdf..46a765bf05c3 100644
--- a/fs/nfs/flexfilelayout/flexfilelayout.c
+++ b/fs/nfs/flexfilelayout/flexfilelayout.c
@@ -171,7 +171,7 @@ ff_local_open_fh(struct pnfs_layout_segment *lseg, u32 ds_idx,
 #if IS_ENABLED(CONFIG_NFS_LOCALIO)
 	struct nfs4_ff_layout_mirror *mirror = FF_LAYOUT_COMP(lseg, ds_idx);
 
-	return nfs_local_open_fh(clp, cred, fh, &mirror->nfl, mode);
+	return nfs_local_open_fh(clp, cred, fh, &mirror->dss[0].nfl, mode);
 #else
 	return NULL;
 #endif
@@ -182,13 +182,13 @@ static bool ff_mirror_match_fh(const struct nfs4_ff_layout_mirror *m1,
 {
 	int i, j;
 
-	if (m1->fh_versions_cnt != m2->fh_versions_cnt)
+	if (m1->dss[0].fh_versions_cnt != m2->dss[0].fh_versions_cnt)
 		return false;
-	for (i = 0; i < m1->fh_versions_cnt; i++) {
+	for (i = 0; i < m1->dss[0].fh_versions_cnt; i++) {
 		bool found_fh = false;
-		for (j = 0; j < m2->fh_versions_cnt; j++) {
-			if (nfs_compare_fh(&m1->fh_versions[i],
-					&m2->fh_versions[j]) == 0) {
+		for (j = 0; j < m2->dss[0].fh_versions_cnt; j++) {
+			if (nfs_compare_fh(&m1->dss[0].fh_versions[i],
+					&m2->dss[0].fh_versions[j]) == 0) {
 				found_fh = true;
 				break;
 			}
@@ -209,7 +209,8 @@ ff_layout_add_mirror(struct pnfs_layout_hdr *lo,
 
 	spin_lock(&inode->i_lock);
 	list_for_each_entry(pos, &ff_layout->mirrors, mirrors) {
-		if (memcmp(&mirror->devid, &pos->devid, sizeof(pos->devid)) != 0)
+		if (memcmp(&mirror->dss[0].devid, &pos->dss[0].devid,
+			   sizeof(pos->dss[0].devid)) != 0)
 			continue;
 		if (!ff_mirror_match_fh(mirror, pos))
 			continue;
@@ -246,23 +247,27 @@ static struct nfs4_ff_layout_mirror *ff_layout_alloc_mirror(gfp_t gfp_flags)
 		spin_lock_init(&mirror->lock);
 		refcount_set(&mirror->ref, 1);
 		INIT_LIST_HEAD(&mirror->mirrors);
-		nfs_localio_file_init(&mirror->nfl);
+		nfs_localio_file_init(&mirror->dss[0].nfl);
 	}
 	return mirror;
 }
 
 static void ff_layout_free_mirror(struct nfs4_ff_layout_mirror *mirror)
 {
-	const struct cred *cred;
+	const struct cred	*cred;
+	int dss_id = 0;
 
 	ff_layout_remove_mirror(mirror);
-	kfree(mirror->fh_versions);
-	nfs_close_local_fh(&mirror->nfl);
-	cred = rcu_access_pointer(mirror->ro_cred);
+
+	kfree(mirror->dss[dss_id].fh_versions);
+	nfs_close_local_fh(&mirror->dss[dss_id].nfl);
+	cred = rcu_access_pointer(mirror->dss[dss_id].ro_cred);
 	put_cred(cred);
-	cred = rcu_access_pointer(mirror->rw_cred);
+	cred = rcu_access_pointer(mirror->dss[dss_id].rw_cred);
 	put_cred(cred);
-	nfs4_ff_layout_put_deviceid(mirror->mirror_ds);
+	nfs4_ff_layout_put_deviceid(mirror->dss[dss_id].mirror_ds);
+
+	kfree(mirror->dss);
 	kfree(mirror);
 }
 
@@ -372,8 +377,8 @@ static void ff_layout_sort_mirrors(struct nfs4_ff_layout_segment *fls)
 
 	for (i = 0; i < fls->mirror_array_cnt - 1; i++) {
 		for (j = i + 1; j < fls->mirror_array_cnt; j++)
-			if (fls->mirror_array[i]->efficiency <
-			    fls->mirror_array[j]->efficiency)
+			if (fls->mirror_array[i]->dss[0].efficiency <
+			    fls->mirror_array[j]->dss[0].efficiency)
 				swap(fls->mirror_array[i],
 				     fls->mirror_array[j]);
 	}
@@ -427,23 +432,25 @@ ff_layout_alloc_lseg(struct pnfs_layout_hdr *lh,
 	fls->mirror_array_cnt = mirror_array_cnt;
 	fls->stripe_unit = stripe_unit;
 
+	u32 dss_count = 0;
 	for (i = 0; i < fls->mirror_array_cnt; i++) {
 		struct nfs4_ff_layout_mirror *mirror;
 		struct cred *kcred;
 		const struct cred __rcu *cred;
 		kuid_t uid;
 		kgid_t gid;
-		u32 ds_count, fh_count, id;
-		int j;
+		u32 fh_count, id;
+		int j, dss_id = 0;
 
 		rc = -EIO;
 		p = xdr_inline_decode(&stream, 4);
 		if (!p)
 			goto out_err_free;
-		ds_count = be32_to_cpup(p);
+
+		dss_count = be32_to_cpup(p);
 
 		/* FIXME: allow for striping? */
-		if (ds_count != 1)
+		if (dss_count != 1)
 			goto out_err_free;
 
 		fls->mirror_array[i] = ff_layout_alloc_mirror(gfp_flags);
@@ -452,10 +459,13 @@ ff_layout_alloc_lseg(struct pnfs_layout_hdr *lh,
 			goto out_err_free;
 		}
 
-		fls->mirror_array[i]->ds_count = ds_count;
+		fls->mirror_array[i]->dss_count = dss_count;
+		fls->mirror_array[i]->dss =
+		    kcalloc(dss_count, sizeof(struct nfs4_ff_layout_ds_stripe),
+			    gfp_flags);
 
 		/* deviceid */
-		rc = decode_deviceid(&stream, &fls->mirror_array[i]->devid);
+		rc = decode_deviceid(&stream, &fls->mirror_array[i]->dss[dss_id].devid);
 		if (rc)
 			goto out_err_free;
 
@@ -464,10 +474,10 @@ ff_layout_alloc_lseg(struct pnfs_layout_hdr *lh,
 		p = xdr_inline_decode(&stream, 4);
 		if (!p)
 			goto out_err_free;
-		fls->mirror_array[i]->efficiency = be32_to_cpup(p);
+		fls->mirror_array[i]->dss[dss_id].efficiency = be32_to_cpup(p);
 
 		/* stateid */
-		rc = decode_pnfs_stateid(&stream, &fls->mirror_array[i]->stateid);
+		rc = decode_pnfs_stateid(&stream, &fls->mirror_array[i]->dss[dss_id].stateid);
 		if (rc)
 			goto out_err_free;
 
@@ -478,22 +488,22 @@ ff_layout_alloc_lseg(struct pnfs_layout_hdr *lh,
 			goto out_err_free;
 		fh_count = be32_to_cpup(p);
 
-		fls->mirror_array[i]->fh_versions =
-			kcalloc(fh_count, sizeof(struct nfs_fh),
-				gfp_flags);
-		if (fls->mirror_array[i]->fh_versions == NULL) {
+		fls->mirror_array[i]->dss[dss_id].fh_versions =
+		    kcalloc(fh_count, sizeof(struct nfs_fh),
+			    gfp_flags);
+		if (fls->mirror_array[i]->dss[dss_id].fh_versions == NULL) {
 			rc = -ENOMEM;
 			goto out_err_free;
 		}
 
 		for (j = 0; j < fh_count; j++) {
 			rc = decode_nfs_fh(&stream,
-					   &fls->mirror_array[i]->fh_versions[j]);
+					   &fls->mirror_array[i]->dss[dss_id].fh_versions[j]);
 			if (rc)
 				goto out_err_free;
 		}
 
-		fls->mirror_array[i]->fh_versions_cnt = fh_count;
+		fls->mirror_array[i]->dss[dss_id].fh_versions_cnt = fh_count;
 
 		/* user */
 		rc = decode_name(&stream, &id);
@@ -524,19 +534,21 @@ ff_layout_alloc_lseg(struct pnfs_layout_hdr *lh,
 		cred = RCU_INITIALIZER(kcred);
 
 		if (lgr->range.iomode == IOMODE_READ)
-			rcu_assign_pointer(fls->mirror_array[i]->ro_cred, cred);
+			rcu_assign_pointer(fls->mirror_array[i]->dss[dss_id].ro_cred, cred);
 		else
-			rcu_assign_pointer(fls->mirror_array[i]->rw_cred, cred);
+			rcu_assign_pointer(fls->mirror_array[i]->dss[dss_id].rw_cred, cred);
 
 		mirror = ff_layout_add_mirror(lh, fls->mirror_array[i]);
 		if (mirror != fls->mirror_array[i]) {
 			/* swap cred ptrs so free_mirror will clean up old */
 			if (lgr->range.iomode == IOMODE_READ) {
-				cred = xchg(&mirror->ro_cred, fls->mirror_array[i]->ro_cred);
-				rcu_assign_pointer(fls->mirror_array[i]->ro_cred, cred);
+				cred = xchg(&mirror->dss[dss_id].ro_cred,
+					    fls->mirror_array[i]->dss[dss_id].ro_cred);
+				rcu_assign_pointer(fls->mirror_array[i]->dss[dss_id].ro_cred, cred);
 			} else {
-				cred = xchg(&mirror->rw_cred, fls->mirror_array[i]->rw_cred);
-				rcu_assign_pointer(fls->mirror_array[i]->rw_cred, cred);
+				cred = xchg(&mirror->dss[dss_id].rw_cred,
+					    fls->mirror_array[i]->dss[dss_id].rw_cred);
+				rcu_assign_pointer(fls->mirror_array[i]->dss[dss_id].rw_cred, cred);
 			}
 			ff_layout_free_mirror(fls->mirror_array[i]);
 			fls->mirror_array[i] = mirror;
@@ -624,8 +636,8 @@ nfs4_ff_layoutstat_start_io(struct nfs4_ff_layout_mirror *mirror,
 	struct nfs4_flexfile_layout *ffl = FF_LAYOUT_FROM_HDR(mirror->layout);
 
 	nfs4_ff_start_busy_timer(&layoutstat->busy_timer, now);
-	if (!mirror->start_time)
-		mirror->start_time = now;
+	if (!mirror->dss[0].start_time)
+		mirror->dss[0].start_time = now;
 	if (mirror->report_interval != 0)
 		report_interval = (s64)mirror->report_interval * 1000LL;
 	else if (layoutstats_timer != 0)
@@ -680,8 +692,8 @@ nfs4_ff_layout_stat_io_start_read(struct inode *inode,
 	bool report;
 
 	spin_lock(&mirror->lock);
-	report = nfs4_ff_layoutstat_start_io(mirror, &mirror->read_stat, now);
-	nfs4_ff_layout_stat_io_update_requested(&mirror->read_stat, requested);
+	report = nfs4_ff_layoutstat_start_io(mirror, &mirror->dss[0].read_stat, now);
+	nfs4_ff_layout_stat_io_update_requested(&mirror->dss[0].read_stat, requested);
 	set_bit(NFS4_FF_MIRROR_STAT_AVAIL, &mirror->flags);
 	spin_unlock(&mirror->lock);
 
@@ -696,7 +708,7 @@ nfs4_ff_layout_stat_io_end_read(struct rpc_task *task,
 		__u64 completed)
 {
 	spin_lock(&mirror->lock);
-	nfs4_ff_layout_stat_io_update_completed(&mirror->read_stat,
+	nfs4_ff_layout_stat_io_update_completed(&mirror->dss[0].read_stat,
 			requested, completed,
 			ktime_get(), task->tk_start);
 	set_bit(NFS4_FF_MIRROR_STAT_AVAIL, &mirror->flags);
@@ -711,8 +723,8 @@ nfs4_ff_layout_stat_io_start_write(struct inode *inode,
 	bool report;
 
 	spin_lock(&mirror->lock);
-	report = nfs4_ff_layoutstat_start_io(mirror , &mirror->write_stat, now);
-	nfs4_ff_layout_stat_io_update_requested(&mirror->write_stat, requested);
+	report = nfs4_ff_layoutstat_start_io(mirror, &mirror->dss[0].write_stat, now);
+	nfs4_ff_layout_stat_io_update_requested(&mirror->dss[0].write_stat, requested);
 	set_bit(NFS4_FF_MIRROR_STAT_AVAIL, &mirror->flags);
 	spin_unlock(&mirror->lock);
 
@@ -731,7 +743,7 @@ nfs4_ff_layout_stat_io_end_write(struct rpc_task *task,
 		requested = completed = 0;
 
 	spin_lock(&mirror->lock);
-	nfs4_ff_layout_stat_io_update_completed(&mirror->write_stat,
+	nfs4_ff_layout_stat_io_update_completed(&mirror->dss[0].write_stat,
 			requested, completed, ktime_get(), task->tk_start);
 	set_bit(NFS4_FF_MIRROR_STAT_AVAIL, &mirror->flags);
 	spin_unlock(&mirror->lock);
@@ -773,7 +785,7 @@ ff_layout_choose_ds_for_read(struct pnfs_layout_segment *lseg,
 			continue;
 
 		if (check_device &&
-		    nfs4_test_deviceid_unavailable(&mirror->mirror_ds->id_node))
+		    nfs4_test_deviceid_unavailable(&mirror->dss[0].mirror_ds->id_node))
 			continue;
 
 		*best_idx = idx;
@@ -879,7 +891,7 @@ ff_layout_pg_init_read(struct nfs_pageio_descriptor *pgio,
 
 	mirror = FF_LAYOUT_COMP(pgio->pg_lseg, ds_idx);
 	pgm = &pgio->pg_mirrors[0];
-	pgm->pg_bsize = mirror->mirror_ds->ds_versions[0].rsize;
+	pgm->pg_bsize = mirror->dss[0].mirror_ds->ds_versions[0].rsize;
 
 	pgio->pg_mirror_idx = ds_idx;
 	return;
@@ -951,7 +963,7 @@ ff_layout_pg_init_write(struct nfs_pageio_descriptor *pgio,
 			goto retry;
 		}
 		pgm = &pgio->pg_mirrors[i];
-		pgm->pg_bsize = mirror->mirror_ds->ds_versions[0].wsize;
+		pgm->pg_bsize = mirror->dss[0].mirror_ds->ds_versions[0].wsize;
 	}
 
 	if (NFS_SERVER(pgio->pg_inode)->flags &
@@ -2021,7 +2033,7 @@ select_ds_fh_from_commit(struct pnfs_layout_segment *lseg, u32 i)
 	/* FIXME: Assume that there is only one NFS version available
 	 * for the DS.
 	 */
-	return &flseg->mirror_array[i]->fh_versions[0];
+	return &flseg->mirror_array[i]->dss[0].fh_versions[0];
 }
 
 static int ff_layout_initiate_commit(struct nfs_commit_data *data, int how)
@@ -2137,10 +2149,10 @@ static void ff_layout_cancel_io(struct pnfs_layout_segment *lseg)
 
 	for (idx = 0; idx < flseg->mirror_array_cnt; idx++) {
 		mirror = flseg->mirror_array[idx];
-		mirror_ds = mirror->mirror_ds;
+		mirror_ds = mirror->dss[0].mirror_ds;
 		if (IS_ERR_OR_NULL(mirror_ds))
 			continue;
-		ds = mirror->mirror_ds->ds;
+		ds = mirror->dss[0].mirror_ds->ds;
 		if (!ds)
 			continue;
 		ds_clp = ds->ds_clp;
@@ -2541,8 +2553,8 @@ ff_layout_encode_ff_layoutupdate(struct xdr_stream *xdr,
 			      struct nfs4_ff_layout_mirror *mirror)
 {
 	struct nfs4_pnfs_ds_addr *da;
-	struct nfs4_pnfs_ds *ds = mirror->mirror_ds->ds;
-	struct nfs_fh *fh = &mirror->fh_versions[0];
+	struct nfs4_pnfs_ds *ds = mirror->dss[0].mirror_ds->ds;
+	struct nfs_fh *fh = &mirror->dss[0].fh_versions[0];
 	__be32 *p;
 
 	da = list_first_entry(&ds->ds_addrs, struct nfs4_pnfs_ds_addr, da_node);
@@ -2555,12 +2567,12 @@ ff_layout_encode_ff_layoutupdate(struct xdr_stream *xdr,
 	xdr_encode_opaque(p, fh->data, fh->size);
 	/* ff_io_latency4 read */
 	spin_lock(&mirror->lock);
-	ff_layout_encode_io_latency(xdr, &mirror->read_stat.io_stat);
+	ff_layout_encode_io_latency(xdr, &mirror->dss[0].read_stat.io_stat);
 	/* ff_io_latency4 write */
-	ff_layout_encode_io_latency(xdr, &mirror->write_stat.io_stat);
+	ff_layout_encode_io_latency(xdr, &mirror->dss[0].write_stat.io_stat);
 	spin_unlock(&mirror->lock);
 	/* nfstime4 */
-	ff_layout_encode_nfstime(xdr, ktime_sub(ktime_get(), mirror->start_time));
+	ff_layout_encode_nfstime(xdr, ktime_sub(ktime_get(), mirror->dss[0].start_time));
 	/* bool */
 	p = xdr_reserve_space(xdr, 4);
 	*p = cpu_to_be32(false);
@@ -2607,7 +2619,7 @@ ff_layout_mirror_prepare_stats(struct pnfs_layout_hdr *lo,
 	list_for_each_entry(mirror, &ff_layout->mirrors, mirrors) {
 		if (i >= dev_limit)
 			break;
-		if (IS_ERR_OR_NULL(mirror->mirror_ds))
+		if (IS_ERR_OR_NULL(mirror->dss[0].mirror_ds))
 			continue;
 		if (!test_and_clear_bit(NFS4_FF_MIRROR_STAT_AVAIL,
 					&mirror->flags) &&
@@ -2616,15 +2628,15 @@ ff_layout_mirror_prepare_stats(struct pnfs_layout_hdr *lo,
 		/* mirror refcount put in cleanup_layoutstats */
 		if (!refcount_inc_not_zero(&mirror->ref))
 			continue;
-		dev = &mirror->mirror_ds->id_node; 
+		dev = &mirror->dss[0].mirror_ds->id_node;
 		memcpy(&devinfo->dev_id, &dev->deviceid, NFS4_DEVICEID4_SIZE);
 		devinfo->offset = 0;
 		devinfo->length = NFS4_MAX_UINT64;
 		spin_lock(&mirror->lock);
-		devinfo->read_count = mirror->read_stat.io_stat.ops_completed;
-		devinfo->read_bytes = mirror->read_stat.io_stat.bytes_completed;
-		devinfo->write_count = mirror->write_stat.io_stat.ops_completed;
-		devinfo->write_bytes = mirror->write_stat.io_stat.bytes_completed;
+		devinfo->read_count = mirror->dss[0].read_stat.io_stat.ops_completed;
+		devinfo->read_bytes = mirror->dss[0].read_stat.io_stat.bytes_completed;
+		devinfo->write_count = mirror->dss[0].write_stat.io_stat.ops_completed;
+		devinfo->write_bytes = mirror->dss[0].write_stat.io_stat.bytes_completed;
 		spin_unlock(&mirror->lock);
 		devinfo->layout_type = LAYOUT_FLEX_FILES;
 		devinfo->ld_private.ops = &layoutstat_ops;
diff --git a/fs/nfs/flexfilelayout/flexfilelayout.h b/fs/nfs/flexfilelayout/flexfilelayout.h
index 095df09017a5..14640452713b 100644
--- a/fs/nfs/flexfilelayout/flexfilelayout.h
+++ b/fs/nfs/flexfilelayout/flexfilelayout.h
@@ -71,12 +71,12 @@ struct nfs4_ff_layoutstat {
 	struct nfs4_ff_busy_timer busy_timer;
 };
 
-struct nfs4_ff_layout_mirror {
-	struct pnfs_layout_hdr		*layout;
-	struct list_head		mirrors;
-	u32				ds_count;
-	u32				efficiency;
+struct nfs4_ff_layout_mirror;
+
+struct nfs4_ff_layout_ds_stripe {
+	struct nfs4_ff_layout_mirror   *mirror;
 	struct nfs4_deviceid		devid;
+	u32				efficiency;
 	struct nfs4_ff_layout_ds	*mirror_ds;
 	u32				fh_versions_cnt;
 	struct nfs_fh			*fh_versions;
@@ -84,12 +84,19 @@ struct nfs4_ff_layout_mirror {
 	const struct cred __rcu		*ro_cred;
 	const struct cred __rcu		*rw_cred;
 	struct nfs_file_localio		nfl;
-	refcount_t			ref;
-	spinlock_t			lock;
-	unsigned long			flags;
 	struct nfs4_ff_layoutstat	read_stat;
 	struct nfs4_ff_layoutstat	write_stat;
 	ktime_t				start_time;
+};
+
+struct nfs4_ff_layout_mirror {
+	struct pnfs_layout_hdr		*layout;
+	struct list_head		mirrors;
+	u32				dss_count;
+	struct nfs4_ff_layout_ds_stripe *dss;
+	refcount_t			ref;
+	spinlock_t			lock;
+	unsigned long			flags;
 	u32				report_interval;
 };
 
@@ -155,7 +162,7 @@ FF_LAYOUT_DEVID_NODE(struct pnfs_layout_segment *lseg, u32 idx)
 	struct nfs4_ff_layout_mirror *mirror = FF_LAYOUT_COMP(lseg, idx);
 
 	if (mirror != NULL) {
-		struct nfs4_ff_layout_ds *mirror_ds = mirror->mirror_ds;
+		struct nfs4_ff_layout_ds *mirror_ds = mirror->dss[0].mirror_ds;
 
 		if (!IS_ERR_OR_NULL(mirror_ds))
 			return &mirror_ds->id_node;
@@ -184,7 +191,7 @@ ff_layout_no_read_on_rw(struct pnfs_layout_segment *lseg)
 static inline int
 nfs4_ff_layout_ds_version(const struct nfs4_ff_layout_mirror *mirror)
 {
-	return mirror->mirror_ds->ds_versions[0].version;
+	return mirror->dss[0].mirror_ds->ds_versions[0].version;
 }
 
 struct nfs4_ff_layout_ds *
diff --git a/fs/nfs/flexfilelayout/flexfilelayoutdev.c b/fs/nfs/flexfilelayout/flexfilelayoutdev.c
index 656d5c50bbce..f8ac9d8bd380 100644
--- a/fs/nfs/flexfilelayout/flexfilelayoutdev.c
+++ b/fs/nfs/flexfilelayout/flexfilelayoutdev.c
@@ -259,7 +259,7 @@ int ff_layout_track_ds_error(struct nfs4_flexfile_layout *flo,
 	if (status == 0)
 		return 0;
 
-	if (IS_ERR_OR_NULL(mirror->mirror_ds))
+	if (IS_ERR_OR_NULL(mirror->dss[0].mirror_ds))
 		return -EINVAL;
 
 	dserr = kmalloc(sizeof(*dserr), gfp_flags);
@@ -271,8 +271,8 @@ int ff_layout_track_ds_error(struct nfs4_flexfile_layout *flo,
 	dserr->length = length;
 	dserr->status = status;
 	dserr->opnum = opnum;
-	nfs4_stateid_copy(&dserr->stateid, &mirror->stateid);
-	memcpy(&dserr->deviceid, &mirror->mirror_ds->id_node.deviceid,
+	nfs4_stateid_copy(&dserr->stateid, &mirror->dss[0].stateid);
+	memcpy(&dserr->deviceid, &mirror->dss[0].mirror_ds->id_node.deviceid,
 	       NFS4_DEVICEID4_SIZE);
 
 	spin_lock(&flo->generic_hdr.plh_inode->i_lock);
@@ -287,9 +287,9 @@ ff_layout_get_mirror_cred(struct nfs4_ff_layout_mirror *mirror, u32 iomode)
 	const struct cred *cred, __rcu **pcred;
 
 	if (iomode == IOMODE_READ)
-		pcred = &mirror->ro_cred;
+		pcred = &mirror->dss[0].ro_cred;
 	else
-		pcred = &mirror->rw_cred;
+		pcred = &mirror->dss[0].rw_cred;
 
 	rcu_read_lock();
 	do {
@@ -307,7 +307,7 @@ struct nfs_fh *
 nfs4_ff_layout_select_ds_fh(struct nfs4_ff_layout_mirror *mirror)
 {
 	/* FIXME: For now assume there is only 1 version available for the DS */
-	return &mirror->fh_versions[0];
+	return &mirror->dss[0].fh_versions[0];
 }
 
 void
@@ -315,7 +315,7 @@ nfs4_ff_layout_select_ds_stateid(const struct nfs4_ff_layout_mirror *mirror,
 		nfs4_stateid *stateid)
 {
 	if (nfs4_ff_layout_ds_version(mirror) == 4)
-		nfs4_stateid_copy(stateid, &mirror->stateid);
+		nfs4_stateid_copy(stateid, &mirror->dss[0].stateid);
 }
 
 static bool
@@ -324,23 +324,23 @@ ff_layout_init_mirror_ds(struct pnfs_layout_hdr *lo,
 {
 	if (mirror == NULL)
 		goto outerr;
-	if (mirror->mirror_ds == NULL) {
+	if (mirror->dss[0].mirror_ds == NULL) {
 		struct nfs4_deviceid_node *node;
 		struct nfs4_ff_layout_ds *mirror_ds = ERR_PTR(-ENODEV);
 
 		node = nfs4_find_get_deviceid(NFS_SERVER(lo->plh_inode),
-				&mirror->devid, lo->plh_lc_cred,
+				&mirror->dss[0].devid, lo->plh_lc_cred,
 				GFP_KERNEL);
 		if (node)
 			mirror_ds = FF_LAYOUT_MIRROR_DS(node);
 
 		/* check for race with another call to this function */
-		if (cmpxchg(&mirror->mirror_ds, NULL, mirror_ds) &&
+		if (cmpxchg(&mirror->dss[0].mirror_ds, NULL, mirror_ds) &&
 		    mirror_ds != ERR_PTR(-ENODEV))
 			nfs4_put_deviceid_node(node);
 	}
 
-	if (IS_ERR(mirror->mirror_ds))
+	if (IS_ERR(mirror->dss[0].mirror_ds))
 		goto outerr;
 
 	return true;
@@ -379,7 +379,7 @@ nfs4_ff_layout_prepare_ds(struct pnfs_layout_segment *lseg,
 	if (!ff_layout_init_mirror_ds(lseg->pls_layout, mirror))
 		goto noconnect;
 
-	ds = mirror->mirror_ds->ds;
+	ds = mirror->dss[0].mirror_ds->ds;
 	if (READ_ONCE(ds->ds_clp))
 		goto out;
 	/* matching smp_wmb() in _nfs4_pnfs_v3/4_ds_connect */
@@ -388,10 +388,10 @@ nfs4_ff_layout_prepare_ds(struct pnfs_layout_segment *lseg,
 	/* FIXME: For now we assume the server sent only one version of NFS
 	 * to use for the DS.
 	 */
-	status = nfs4_pnfs_ds_connect(s, ds, &mirror->mirror_ds->id_node,
+	status = nfs4_pnfs_ds_connect(s, ds, &mirror->dss[0].mirror_ds->id_node,
 			     dataserver_timeo, dataserver_retrans,
-			     mirror->mirror_ds->ds_versions[0].version,
-			     mirror->mirror_ds->ds_versions[0].minor_version);
+			     mirror->dss[0].mirror_ds->ds_versions[0].version,
+			     mirror->dss[0].mirror_ds->ds_versions[0].minor_version);
 
 	/* connect success, check rsize/wsize limit */
 	if (!status) {
@@ -404,10 +404,10 @@ nfs4_ff_layout_prepare_ds(struct pnfs_layout_segment *lseg,
 		max_payload =
 			nfs_block_size(rpc_max_payload(ds->ds_clp->cl_rpcclient),
 				       NULL);
-		if (mirror->mirror_ds->ds_versions[0].rsize > max_payload)
-			mirror->mirror_ds->ds_versions[0].rsize = max_payload;
-		if (mirror->mirror_ds->ds_versions[0].wsize > max_payload)
-			mirror->mirror_ds->ds_versions[0].wsize = max_payload;
+		if (mirror->dss[0].mirror_ds->ds_versions[0].rsize > max_payload)
+			mirror->dss[0].mirror_ds->ds_versions[0].rsize = max_payload;
+		if (mirror->dss[0].mirror_ds->ds_versions[0].wsize > max_payload)
+			mirror->dss[0].mirror_ds->ds_versions[0].wsize = max_payload;
 		goto out;
 	}
 noconnect:
@@ -430,7 +430,7 @@ ff_layout_get_ds_cred(struct nfs4_ff_layout_mirror *mirror,
 {
 	const struct cred *cred;
 
-	if (mirror && !mirror->mirror_ds->ds_versions[0].tightly_coupled) {
+	if (mirror && !mirror->dss[0].mirror_ds->ds_versions[0].tightly_coupled) {
 		cred = ff_layout_get_mirror_cred(mirror, range->iomode);
 		if (!cred)
 			cred = get_cred(mdscred);
@@ -453,7 +453,7 @@ struct rpc_clnt *
 nfs4_ff_find_or_create_ds_client(struct nfs4_ff_layout_mirror *mirror,
 				 struct nfs_client *ds_clp, struct inode *inode)
 {
-	switch (mirror->mirror_ds->ds_versions[0].version) {
+	switch (mirror->dss[0].mirror_ds->ds_versions[0].version) {
 	case 3:
 		/* For NFSv3 DS, flavor is set when creating DS connections */
 		return ds_clp->cl_rpcclient;
@@ -564,11 +564,11 @@ static bool ff_read_layout_has_available_ds(struct pnfs_layout_segment *lseg)
 	for (idx = 0; idx < FF_LAYOUT_MIRROR_COUNT(lseg); idx++) {
 		mirror = FF_LAYOUT_COMP(lseg, idx);
 		if (mirror) {
-			if (!mirror->mirror_ds)
+			if (!mirror->dss[0].mirror_ds)
 				return true;
-			if (IS_ERR(mirror->mirror_ds))
+			if (IS_ERR(mirror->dss[0].mirror_ds))
 				continue;
-			devid = &mirror->mirror_ds->id_node;
+			devid = &mirror->dss[0].mirror_ds->id_node;
 			if (!nfs4_test_deviceid_unavailable(devid))
 				return true;
 		}
@@ -585,11 +585,11 @@ static bool ff_rw_layout_has_available_ds(struct pnfs_layout_segment *lseg)
 
 	for (idx = 0; idx < FF_LAYOUT_MIRROR_COUNT(lseg); idx++) {
 		mirror = FF_LAYOUT_COMP(lseg, idx);
-		if (!mirror || IS_ERR(mirror->mirror_ds))
+		if (!mirror || IS_ERR(mirror->dss[0].mirror_ds))
 			return false;
-		if (!mirror->mirror_ds)
+		if (!mirror->dss[0].mirror_ds)
 			continue;
-		devid = &mirror->mirror_ds->id_node;
+		devid = &mirror->dss[0].mirror_ds->id_node;
 		if (nfs4_test_deviceid_unavailable(devid))
 			return false;
 	}
-- 
2.34.1

[PATCH 4/9] NFSv4/flexfiles: Update low level helper functions to be DS stripe aware.

[Jonathan Curley]

Updates common helper functions to be dss_id aware. Most cases simply
add a dss_id parameter. The has_available functions have been updated
with a loop.

Signed-off-by: Jonathan Curley <jcurley@purestorage.com>
---
 fs/nfs/flexfilelayout/flexfilelayout.c    |  56 +++++------
 fs/nfs/flexfilelayout/flexfilelayout.h    |  39 +++++---
 fs/nfs/flexfilelayout/flexfilelayoutdev.c | 110 ++++++++++++----------
 3 files changed, 116 insertions(+), 89 deletions(-)

diff --git a/fs/nfs/flexfilelayout/flexfilelayout.c b/fs/nfs/flexfilelayout/flexfilelayout.c
index 46a765bf05c3..a2a3821f190c 100644
--- a/fs/nfs/flexfilelayout/flexfilelayout.c
+++ b/fs/nfs/flexfilelayout/flexfilelayout.c
@@ -164,14 +164,14 @@ decode_name(struct xdr_stream *xdr, u32 *id)
 }
 
 static struct nfsd_file *
-ff_local_open_fh(struct pnfs_layout_segment *lseg, u32 ds_idx,
+ff_local_open_fh(struct pnfs_layout_segment *lseg, u32 ds_idx, u32 dss_id,
 		 struct nfs_client *clp, const struct cred *cred,
 		 struct nfs_fh *fh, fmode_t mode)
 {
 #if IS_ENABLED(CONFIG_NFS_LOCALIO)
 	struct nfs4_ff_layout_mirror *mirror = FF_LAYOUT_COMP(lseg, ds_idx);
 
-	return nfs_local_open_fh(clp, cred, fh, &mirror->dss[0].nfl, mode);
+	return nfs_local_open_fh(clp, cred, fh, &mirror->dss[dss_id].nfl, mode);
 #else
 	return NULL;
 #endif
@@ -752,7 +752,7 @@ nfs4_ff_layout_stat_io_end_write(struct rpc_task *task,
 static void
 ff_layout_mark_ds_unreachable(struct pnfs_layout_segment *lseg, u32 idx)
 {
-	struct nfs4_deviceid_node *devid = FF_LAYOUT_DEVID_NODE(lseg, idx);
+	struct nfs4_deviceid_node *devid = FF_LAYOUT_DEVID_NODE(lseg, idx, 0);
 
 	if (devid)
 		nfs4_mark_deviceid_unavailable(devid);
@@ -761,7 +761,7 @@ ff_layout_mark_ds_unreachable(struct pnfs_layout_segment *lseg, u32 idx)
 static void
 ff_layout_mark_ds_reachable(struct pnfs_layout_segment *lseg, u32 idx)
 {
-	struct nfs4_deviceid_node *devid = FF_LAYOUT_DEVID_NODE(lseg, idx);
+	struct nfs4_deviceid_node *devid = FF_LAYOUT_DEVID_NODE(lseg, idx, 0);
 
 	if (devid)
 		nfs4_mark_deviceid_available(devid);
@@ -780,7 +780,7 @@ ff_layout_choose_ds_for_read(struct pnfs_layout_segment *lseg,
 	/* mirrors are initially sorted by efficiency */
 	for (idx = start_idx; idx < fls->mirror_array_cnt; idx++) {
 		mirror = FF_LAYOUT_COMP(lseg, idx);
-		ds = nfs4_ff_layout_prepare_ds(lseg, mirror, false);
+		ds = nfs4_ff_layout_prepare_ds(lseg, mirror, 0, false);
 		if (!ds)
 			continue;
 
@@ -953,7 +953,7 @@ ff_layout_pg_init_write(struct nfs_pageio_descriptor *pgio,
 
 	for (i = 0; i < pgio->pg_mirror_count; i++) {
 		mirror = FF_LAYOUT_COMP(pgio->pg_lseg, i);
-		ds = nfs4_ff_layout_prepare_ds(pgio->pg_lseg, mirror, true);
+		ds = nfs4_ff_layout_prepare_ds(pgio->pg_lseg, mirror, 0, true);
 		if (!ds) {
 			if (!ff_layout_no_fallback_to_mds(pgio->pg_lseg))
 				goto out_mds;
@@ -1125,7 +1125,7 @@ static int ff_layout_async_handle_error_v4(struct rpc_task *task,
 {
 	struct pnfs_layout_hdr *lo = lseg->pls_layout;
 	struct inode *inode = lo->plh_inode;
-	struct nfs4_deviceid_node *devid = FF_LAYOUT_DEVID_NODE(lseg, idx);
+	struct nfs4_deviceid_node *devid = FF_LAYOUT_DEVID_NODE(lseg, idx, 0);
 	struct nfs4_slot_table *tbl = &clp->cl_session->fc_slot_table;
 
 	switch (op_status) {
@@ -1224,7 +1224,7 @@ static int ff_layout_async_handle_error_v3(struct rpc_task *task,
 					   struct pnfs_layout_segment *lseg,
 					   u32 idx)
 {
-	struct nfs4_deviceid_node *devid = FF_LAYOUT_DEVID_NODE(lseg, idx);
+	struct nfs4_deviceid_node *devid = FF_LAYOUT_DEVID_NODE(lseg, idx, 0);
 
 	switch (op_status) {
 	case NFS_OK:
@@ -1354,7 +1354,7 @@ static void ff_layout_io_track_ds_error(struct pnfs_layout_segment *lseg,
 
 	mirror = FF_LAYOUT_COMP(lseg, idx);
 	err = ff_layout_track_ds_error(FF_LAYOUT_FROM_HDR(lseg->pls_layout),
-				       mirror, offset, length, status, opnum,
+				       mirror, 0, offset, length, status, opnum,
 				       nfs_io_gfp_mask());
 
 	switch (status) {
@@ -1885,20 +1885,20 @@ ff_layout_read_pagelist(struct nfs_pgio_header *hdr)
 		hdr->args.pgbase, (size_t)hdr->args.count, offset);
 
 	mirror = FF_LAYOUT_COMP(lseg, idx);
-	ds = nfs4_ff_layout_prepare_ds(lseg, mirror, false);
+	ds = nfs4_ff_layout_prepare_ds(lseg, mirror, 0, false);
 	if (!ds)
 		goto out_failed;
 
 	ds_clnt = nfs4_ff_find_or_create_ds_client(mirror, ds->ds_clp,
-						   hdr->inode);
+						   hdr->inode, 0);
 	if (IS_ERR(ds_clnt))
 		goto out_failed;
 
-	ds_cred = ff_layout_get_ds_cred(mirror, &lseg->pls_range, hdr->cred);
+	ds_cred = ff_layout_get_ds_cred(mirror, &lseg->pls_range, hdr->cred, 0);
 	if (!ds_cred)
 		goto out_failed;
 
-	vers = nfs4_ff_layout_ds_version(mirror);
+	vers = nfs4_ff_layout_ds_version(mirror, 0);
 
 	dprintk("%s USE DS: %s cl_count %d vers %d\n", __func__,
 		ds->ds_remotestr, refcount_read(&ds->ds_clp->cl_count), vers);
@@ -1906,11 +1906,11 @@ ff_layout_read_pagelist(struct nfs_pgio_header *hdr)
 	hdr->pgio_done_cb = ff_layout_read_done_cb;
 	refcount_inc(&ds->ds_clp->cl_count);
 	hdr->ds_clp = ds->ds_clp;
-	fh = nfs4_ff_layout_select_ds_fh(mirror);
+	fh = nfs4_ff_layout_select_ds_fh(mirror, 0);
 	if (fh)
 		hdr->args.fh = fh;
 
-	nfs4_ff_layout_select_ds_stateid(mirror, &hdr->args.stateid);
+	nfs4_ff_layout_select_ds_stateid(mirror, 0, &hdr->args.stateid);
 
 	/*
 	 * Note that if we ever decide to split across DSes,
@@ -1920,7 +1920,7 @@ ff_layout_read_pagelist(struct nfs_pgio_header *hdr)
 	hdr->mds_offset = offset;
 
 	/* Start IO accounting for local read */
-	localio = ff_local_open_fh(lseg, idx, ds->ds_clp, ds_cred, fh, FMODE_READ);
+	localio = ff_local_open_fh(lseg, idx, 0, ds->ds_clp, ds_cred, fh, FMODE_READ);
 	if (localio) {
 		hdr->task.tk_start = ktime_get();
 		ff_layout_read_record_layoutstats_start(&hdr->task, hdr);
@@ -1959,20 +1959,20 @@ ff_layout_write_pagelist(struct nfs_pgio_header *hdr, int sync)
 	u32 idx = hdr->pgio_mirror_idx;
 
 	mirror = FF_LAYOUT_COMP(lseg, idx);
-	ds = nfs4_ff_layout_prepare_ds(lseg, mirror, true);
+	ds = nfs4_ff_layout_prepare_ds(lseg, mirror, 0, true);
 	if (!ds)
 		goto out_failed;
 
 	ds_clnt = nfs4_ff_find_or_create_ds_client(mirror, ds->ds_clp,
-						   hdr->inode);
+						   hdr->inode, 0);
 	if (IS_ERR(ds_clnt))
 		goto out_failed;
 
-	ds_cred = ff_layout_get_ds_cred(mirror, &lseg->pls_range, hdr->cred);
+	ds_cred = ff_layout_get_ds_cred(mirror, &lseg->pls_range, hdr->cred, 0);
 	if (!ds_cred)
 		goto out_failed;
 
-	vers = nfs4_ff_layout_ds_version(mirror);
+	vers = nfs4_ff_layout_ds_version(mirror, 0);
 
 	dprintk("%s ino %lu sync %d req %zu@%llu DS: %s cl_count %d vers %d\n",
 		__func__, hdr->inode->i_ino, sync, (size_t) hdr->args.count,
@@ -1983,11 +1983,11 @@ ff_layout_write_pagelist(struct nfs_pgio_header *hdr, int sync)
 	refcount_inc(&ds->ds_clp->cl_count);
 	hdr->ds_clp = ds->ds_clp;
 	hdr->ds_commit_idx = idx;
-	fh = nfs4_ff_layout_select_ds_fh(mirror);
+	fh = nfs4_ff_layout_select_ds_fh(mirror, 0);
 	if (fh)
 		hdr->args.fh = fh;
 
-	nfs4_ff_layout_select_ds_stateid(mirror, &hdr->args.stateid);
+	nfs4_ff_layout_select_ds_stateid(mirror, 0, &hdr->args.stateid);
 
 	/*
 	 * Note that if we ever decide to split across DSes,
@@ -1996,7 +1996,7 @@ ff_layout_write_pagelist(struct nfs_pgio_header *hdr, int sync)
 	hdr->args.offset = offset;
 
 	/* Start IO accounting for local write */
-	localio = ff_local_open_fh(lseg, idx, ds->ds_clp, ds_cred, fh,
+	localio = ff_local_open_fh(lseg, idx, 0, ds->ds_clp, ds_cred, fh,
 				   FMODE_READ|FMODE_WRITE);
 	if (localio) {
 		hdr->task.tk_start = ktime_get();
@@ -2054,20 +2054,20 @@ static int ff_layout_initiate_commit(struct nfs_commit_data *data, int how)
 
 	idx = calc_ds_index_from_commit(lseg, data->ds_commit_index);
 	mirror = FF_LAYOUT_COMP(lseg, idx);
-	ds = nfs4_ff_layout_prepare_ds(lseg, mirror, true);
+	ds = nfs4_ff_layout_prepare_ds(lseg, mirror, 0, true);
 	if (!ds)
 		goto out_err;
 
 	ds_clnt = nfs4_ff_find_or_create_ds_client(mirror, ds->ds_clp,
-						   data->inode);
+						   data->inode, 0);
 	if (IS_ERR(ds_clnt))
 		goto out_err;
 
-	ds_cred = ff_layout_get_ds_cred(mirror, &lseg->pls_range, data->cred);
+	ds_cred = ff_layout_get_ds_cred(mirror, &lseg->pls_range, data->cred, 0);
 	if (!ds_cred)
 		goto out_err;
 
-	vers = nfs4_ff_layout_ds_version(mirror);
+	vers = nfs4_ff_layout_ds_version(mirror, 0);
 
 	dprintk("%s ino %lu, how %d cl_count %d vers %d\n", __func__,
 		data->inode->i_ino, how, refcount_read(&ds->ds_clp->cl_count),
@@ -2081,7 +2081,7 @@ static int ff_layout_initiate_commit(struct nfs_commit_data *data, int how)
 		data->args.fh = fh;
 
 	/* Start IO accounting for local commit */
-	localio = ff_local_open_fh(lseg, idx, ds->ds_clp, ds_cred, fh,
+	localio = ff_local_open_fh(lseg, idx, 0, ds->ds_clp, ds_cred, fh,
 				   FMODE_READ|FMODE_WRITE);
 	if (localio) {
 		data->task.tk_start = ktime_get();
diff --git a/fs/nfs/flexfilelayout/flexfilelayout.h b/fs/nfs/flexfilelayout/flexfilelayout.h
index 14640452713b..142324d6d5c5 100644
--- a/fs/nfs/flexfilelayout/flexfilelayout.h
+++ b/fs/nfs/flexfilelayout/flexfilelayout.h
@@ -157,12 +157,12 @@ FF_LAYOUT_COMP(struct pnfs_layout_segment *lseg, u32 idx)
 }
 
 static inline struct nfs4_deviceid_node *
-FF_LAYOUT_DEVID_NODE(struct pnfs_layout_segment *lseg, u32 idx)
+FF_LAYOUT_DEVID_NODE(struct pnfs_layout_segment *lseg, u32 idx, u32 dss_id)
 {
 	struct nfs4_ff_layout_mirror *mirror = FF_LAYOUT_COMP(lseg, idx);
 
 	if (mirror != NULL) {
-		struct nfs4_ff_layout_ds *mirror_ds = mirror->dss[0].mirror_ds;
+		struct nfs4_ff_layout_ds *mirror_ds = mirror->dss[dss_id].mirror_ds;
 
 		if (!IS_ERR_OR_NULL(mirror_ds))
 			return &mirror_ds->id_node;
@@ -189,9 +189,22 @@ ff_layout_no_read_on_rw(struct pnfs_layout_segment *lseg)
 }
 
 static inline int
-nfs4_ff_layout_ds_version(const struct nfs4_ff_layout_mirror *mirror)
+nfs4_ff_layout_ds_version(const struct nfs4_ff_layout_mirror *mirror, u32 dss_id)
 {
-	return mirror->dss[0].mirror_ds->ds_versions[0].version;
+	return mirror->dss[dss_id].mirror_ds->ds_versions[0].version;
+}
+
+static inline u32
+nfs4_ff_layout_calc_dss_id(const u64 stripe_unit, const u32 dss_count, const loff_t offset)
+{
+	u64 tmp = offset;
+
+	if (dss_count == 1 || stripe_unit == 0)
+		return 0;
+
+	do_div(tmp, stripe_unit);
+
+	return do_div(tmp, dss_count);
 }
 
 struct nfs4_ff_layout_ds *
@@ -200,9 +213,9 @@ nfs4_ff_alloc_deviceid_node(struct nfs_server *server, struct pnfs_device *pdev,
 void nfs4_ff_layout_put_deviceid(struct nfs4_ff_layout_ds *mirror_ds);
 void nfs4_ff_layout_free_deviceid(struct nfs4_ff_layout_ds *mirror_ds);
 int ff_layout_track_ds_error(struct nfs4_flexfile_layout *flo,
-			     struct nfs4_ff_layout_mirror *mirror, u64 offset,
-			     u64 length, int status, enum nfs_opnum4 opnum,
-			     gfp_t gfp_flags);
+			     struct nfs4_ff_layout_mirror *mirror,
+			     u32 dss_id, u64 offset, u64 length, int status,
+			     enum nfs_opnum4 opnum, gfp_t gfp_flags);
 void ff_layout_send_layouterror(struct pnfs_layout_segment *lseg);
 int ff_layout_encode_ds_ioerr(struct xdr_stream *xdr, const struct list_head *head);
 void ff_layout_free_ds_ioerr(struct list_head *head);
@@ -211,23 +224,27 @@ unsigned int ff_layout_fetch_ds_ioerr(struct pnfs_layout_hdr *lo,
 		struct list_head *head,
 		unsigned int maxnum);
 struct nfs_fh *
-nfs4_ff_layout_select_ds_fh(struct nfs4_ff_layout_mirror *mirror);
+nfs4_ff_layout_select_ds_fh(struct nfs4_ff_layout_mirror *mirror, u32 dss_id);
 void
 nfs4_ff_layout_select_ds_stateid(const struct nfs4_ff_layout_mirror *mirror,
-		nfs4_stateid *stateid);
+				 u32 dss_id,
+				 nfs4_stateid *stateid);
 
 struct nfs4_pnfs_ds *
 nfs4_ff_layout_prepare_ds(struct pnfs_layout_segment *lseg,
 			  struct nfs4_ff_layout_mirror *mirror,
+			  u32 dss_id,
 			  bool fail_return);
 
 struct rpc_clnt *
 nfs4_ff_find_or_create_ds_client(struct nfs4_ff_layout_mirror *mirror,
 				 struct nfs_client *ds_clp,
-				 struct inode *inode);
+				 struct inode *inode,
+				 u32 dss_id);
 const struct cred *ff_layout_get_ds_cred(struct nfs4_ff_layout_mirror *mirror,
 					 const struct pnfs_layout_range *range,
-					 const struct cred *mdscred);
+					 const struct cred *mdscred,
+					 u32 dss_id);
 bool ff_layout_avoid_mds_available_ds(struct pnfs_layout_segment *lseg);
 bool ff_layout_avoid_read_on_rw(struct pnfs_layout_segment *lseg);
 
diff --git a/fs/nfs/flexfilelayout/flexfilelayoutdev.c b/fs/nfs/flexfilelayout/flexfilelayoutdev.c
index f8ac9d8bd380..e6623ab6742d 100644
--- a/fs/nfs/flexfilelayout/flexfilelayoutdev.c
+++ b/fs/nfs/flexfilelayout/flexfilelayoutdev.c
@@ -250,16 +250,16 @@ ff_layout_add_ds_error_locked(struct nfs4_flexfile_layout *flo,
 }
 
 int ff_layout_track_ds_error(struct nfs4_flexfile_layout *flo,
-			     struct nfs4_ff_layout_mirror *mirror, u64 offset,
-			     u64 length, int status, enum nfs_opnum4 opnum,
-			     gfp_t gfp_flags)
+			     struct nfs4_ff_layout_mirror *mirror,
+			     u32 dss_id, u64 offset, u64 length, int status,
+			     enum nfs_opnum4 opnum, gfp_t gfp_flags)
 {
 	struct nfs4_ff_layout_ds_err *dserr;
 
 	if (status == 0)
 		return 0;
 
-	if (IS_ERR_OR_NULL(mirror->dss[0].mirror_ds))
+	if (IS_ERR_OR_NULL(mirror->dss[dss_id].mirror_ds))
 		return -EINVAL;
 
 	dserr = kmalloc(sizeof(*dserr), gfp_flags);
@@ -271,8 +271,8 @@ int ff_layout_track_ds_error(struct nfs4_flexfile_layout *flo,
 	dserr->length = length;
 	dserr->status = status;
 	dserr->opnum = opnum;
-	nfs4_stateid_copy(&dserr->stateid, &mirror->dss[0].stateid);
-	memcpy(&dserr->deviceid, &mirror->dss[0].mirror_ds->id_node.deviceid,
+	nfs4_stateid_copy(&dserr->stateid, &mirror->dss[dss_id].stateid);
+	memcpy(&dserr->deviceid, &mirror->dss[dss_id].mirror_ds->id_node.deviceid,
 	       NFS4_DEVICEID4_SIZE);
 
 	spin_lock(&flo->generic_hdr.plh_inode->i_lock);
@@ -282,14 +282,14 @@ int ff_layout_track_ds_error(struct nfs4_flexfile_layout *flo,
 }
 
 static const struct cred *
-ff_layout_get_mirror_cred(struct nfs4_ff_layout_mirror *mirror, u32 iomode)
+ff_layout_get_mirror_cred(struct nfs4_ff_layout_mirror *mirror, u32 iomode, u32 dss_id)
 {
 	const struct cred *cred, __rcu **pcred;
 
 	if (iomode == IOMODE_READ)
-		pcred = &mirror->dss[0].ro_cred;
+		pcred = &mirror->dss[dss_id].ro_cred;
 	else
-		pcred = &mirror->dss[0].rw_cred;
+		pcred = &mirror->dss[dss_id].rw_cred;
 
 	rcu_read_lock();
 	do {
@@ -304,43 +304,45 @@ ff_layout_get_mirror_cred(struct nfs4_ff_layout_mirror *mirror, u32 iomode)
 }
 
 struct nfs_fh *
-nfs4_ff_layout_select_ds_fh(struct nfs4_ff_layout_mirror *mirror)
+nfs4_ff_layout_select_ds_fh(struct nfs4_ff_layout_mirror *mirror, u32 dss_id)
 {
 	/* FIXME: For now assume there is only 1 version available for the DS */
-	return &mirror->dss[0].fh_versions[0];
+	return &mirror->dss[dss_id].fh_versions[0];
 }
 
 void
 nfs4_ff_layout_select_ds_stateid(const struct nfs4_ff_layout_mirror *mirror,
-		nfs4_stateid *stateid)
+				 u32 dss_id,
+				 nfs4_stateid *stateid)
 {
-	if (nfs4_ff_layout_ds_version(mirror) == 4)
-		nfs4_stateid_copy(stateid, &mirror->dss[0].stateid);
+	if (nfs4_ff_layout_ds_version(mirror, dss_id) == 4)
+		nfs4_stateid_copy(stateid, &mirror->dss[dss_id].stateid);
 }
 
 static bool
 ff_layout_init_mirror_ds(struct pnfs_layout_hdr *lo,
-			 struct nfs4_ff_layout_mirror *mirror)
+			 struct nfs4_ff_layout_mirror *mirror,
+			 u32 dss_id)
 {
 	if (mirror == NULL)
 		goto outerr;
-	if (mirror->dss[0].mirror_ds == NULL) {
+	if (mirror->dss[dss_id].mirror_ds == NULL) {
 		struct nfs4_deviceid_node *node;
 		struct nfs4_ff_layout_ds *mirror_ds = ERR_PTR(-ENODEV);
 
 		node = nfs4_find_get_deviceid(NFS_SERVER(lo->plh_inode),
-				&mirror->dss[0].devid, lo->plh_lc_cred,
+				&mirror->dss[dss_id].devid, lo->plh_lc_cred,
 				GFP_KERNEL);
 		if (node)
 			mirror_ds = FF_LAYOUT_MIRROR_DS(node);
 
 		/* check for race with another call to this function */
-		if (cmpxchg(&mirror->dss[0].mirror_ds, NULL, mirror_ds) &&
+		if (cmpxchg(&mirror->dss[dss_id].mirror_ds, NULL, mirror_ds) &&
 		    mirror_ds != ERR_PTR(-ENODEV))
 			nfs4_put_deviceid_node(node);
 	}
 
-	if (IS_ERR(mirror->dss[0].mirror_ds))
+	if (IS_ERR(mirror->dss[dss_id].mirror_ds))
 		goto outerr;
 
 	return true;
@@ -368,6 +370,7 @@ ff_layout_init_mirror_ds(struct pnfs_layout_hdr *lo,
 struct nfs4_pnfs_ds *
 nfs4_ff_layout_prepare_ds(struct pnfs_layout_segment *lseg,
 			  struct nfs4_ff_layout_mirror *mirror,
+			  u32 dss_id,
 			  bool fail_return)
 {
 	struct nfs4_pnfs_ds *ds = NULL;
@@ -376,10 +379,10 @@ nfs4_ff_layout_prepare_ds(struct pnfs_layout_segment *lseg,
 	unsigned int max_payload;
 	int status;
 
-	if (!ff_layout_init_mirror_ds(lseg->pls_layout, mirror))
+	if (!ff_layout_init_mirror_ds(lseg->pls_layout, mirror, dss_id))
 		goto noconnect;
 
-	ds = mirror->dss[0].mirror_ds->ds;
+	ds = mirror->dss[dss_id].mirror_ds->ds;
 	if (READ_ONCE(ds->ds_clp))
 		goto out;
 	/* matching smp_wmb() in _nfs4_pnfs_v3/4_ds_connect */
@@ -388,10 +391,10 @@ nfs4_ff_layout_prepare_ds(struct pnfs_layout_segment *lseg,
 	/* FIXME: For now we assume the server sent only one version of NFS
 	 * to use for the DS.
 	 */
-	status = nfs4_pnfs_ds_connect(s, ds, &mirror->dss[0].mirror_ds->id_node,
+	status = nfs4_pnfs_ds_connect(s, ds, &mirror->dss[dss_id].mirror_ds->id_node,
 			     dataserver_timeo, dataserver_retrans,
-			     mirror->dss[0].mirror_ds->ds_versions[0].version,
-			     mirror->dss[0].mirror_ds->ds_versions[0].minor_version);
+			     mirror->dss[dss_id].mirror_ds->ds_versions[0].version,
+			     mirror->dss[dss_id].mirror_ds->ds_versions[0].minor_version);
 
 	/* connect success, check rsize/wsize limit */
 	if (!status) {
@@ -404,15 +407,15 @@ nfs4_ff_layout_prepare_ds(struct pnfs_layout_segment *lseg,
 		max_payload =
 			nfs_block_size(rpc_max_payload(ds->ds_clp->cl_rpcclient),
 				       NULL);
-		if (mirror->dss[0].mirror_ds->ds_versions[0].rsize > max_payload)
-			mirror->dss[0].mirror_ds->ds_versions[0].rsize = max_payload;
-		if (mirror->dss[0].mirror_ds->ds_versions[0].wsize > max_payload)
-			mirror->dss[0].mirror_ds->ds_versions[0].wsize = max_payload;
+		if (mirror->dss[dss_id].mirror_ds->ds_versions[0].rsize > max_payload)
+			mirror->dss[dss_id].mirror_ds->ds_versions[0].rsize = max_payload;
+		if (mirror->dss[dss_id].mirror_ds->ds_versions[0].wsize > max_payload)
+			mirror->dss[dss_id].mirror_ds->ds_versions[0].wsize = max_payload;
 		goto out;
 	}
 noconnect:
 	ff_layout_track_ds_error(FF_LAYOUT_FROM_HDR(lseg->pls_layout),
-				 mirror, lseg->pls_range.offset,
+				 mirror, dss_id, lseg->pls_range.offset,
 				 lseg->pls_range.length, NFS4ERR_NXIO,
 				 OP_ILLEGAL, GFP_NOIO);
 	ff_layout_send_layouterror(lseg);
@@ -426,12 +429,13 @@ nfs4_ff_layout_prepare_ds(struct pnfs_layout_segment *lseg,
 const struct cred *
 ff_layout_get_ds_cred(struct nfs4_ff_layout_mirror *mirror,
 		      const struct pnfs_layout_range *range,
-		      const struct cred *mdscred)
+		      const struct cred *mdscred,
+		      u32 dss_id)
 {
 	const struct cred *cred;
 
-	if (mirror && !mirror->dss[0].mirror_ds->ds_versions[0].tightly_coupled) {
-		cred = ff_layout_get_mirror_cred(mirror, range->iomode);
+	if (mirror && !mirror->dss[dss_id].mirror_ds->ds_versions[0].tightly_coupled) {
+		cred = ff_layout_get_mirror_cred(mirror, range->iomode, dss_id);
 		if (!cred)
 			cred = get_cred(mdscred);
 	} else {
@@ -445,15 +449,17 @@ ff_layout_get_ds_cred(struct nfs4_ff_layout_mirror *mirror,
  * @mirror: pointer to the mirror
  * @ds_clp: nfs_client for the DS
  * @inode: pointer to inode
+ * @dss_id: DS stripe id
  *
  * Find or create a DS rpc client with th MDS server rpc client auth flavor
  * in the nfs_client cl_ds_clients list.
  */
 struct rpc_clnt *
 nfs4_ff_find_or_create_ds_client(struct nfs4_ff_layout_mirror *mirror,
-				 struct nfs_client *ds_clp, struct inode *inode)
+				 struct nfs_client *ds_clp, struct inode *inode,
+				 u32 dss_id)
 {
-	switch (mirror->dss[0].mirror_ds->ds_versions[0].version) {
+	switch (mirror->dss[dss_id].mirror_ds->ds_versions[0].version) {
 	case 3:
 		/* For NFSv3 DS, flavor is set when creating DS connections */
 		return ds_clp->cl_rpcclient;
@@ -559,18 +565,20 @@ static bool ff_read_layout_has_available_ds(struct pnfs_layout_segment *lseg)
 {
 	struct nfs4_ff_layout_mirror *mirror;
 	struct nfs4_deviceid_node *devid;
-	u32 idx;
+	u32 idx, dss_id;
 
 	for (idx = 0; idx < FF_LAYOUT_MIRROR_COUNT(lseg); idx++) {
 		mirror = FF_LAYOUT_COMP(lseg, idx);
 		if (mirror) {
-			if (!mirror->dss[0].mirror_ds)
-				return true;
-			if (IS_ERR(mirror->dss[0].mirror_ds))
-				continue;
-			devid = &mirror->dss[0].mirror_ds->id_node;
-			if (!nfs4_test_deviceid_unavailable(devid))
-				return true;
+			for (dss_id = 0; dss_id < mirror->dss_count; dss_id++) {
+				if (!mirror->dss[dss_id].mirror_ds)
+					return true;
+				if (IS_ERR(mirror->dss[dss_id].mirror_ds))
+					continue;
+				devid = &mirror->dss[dss_id].mirror_ds->id_node;
+				if (!nfs4_test_deviceid_unavailable(devid))
+					return true;
+			}
 		}
 	}
 
@@ -581,17 +589,19 @@ static bool ff_rw_layout_has_available_ds(struct pnfs_layout_segment *lseg)
 {
 	struct nfs4_ff_layout_mirror *mirror;
 	struct nfs4_deviceid_node *devid;
-	u32 idx;
+	u32 idx, dss_id;
 
 	for (idx = 0; idx < FF_LAYOUT_MIRROR_COUNT(lseg); idx++) {
 		mirror = FF_LAYOUT_COMP(lseg, idx);
-		if (!mirror || IS_ERR(mirror->dss[0].mirror_ds))
-			return false;
-		if (!mirror->dss[0].mirror_ds)
-			continue;
-		devid = &mirror->dss[0].mirror_ds->id_node;
-		if (nfs4_test_deviceid_unavailable(devid))
-			return false;
+		for (dss_id = 0; dss_id < mirror->dss_count; dss_id++) {
+			if (!mirror || IS_ERR(mirror->dss[dss_id].mirror_ds))
+				return false;
+			if (!mirror->dss[dss_id].mirror_ds)
+				continue;
+			devid = &mirror->dss[dss_id].mirror_ds->id_node;
+			if (nfs4_test_deviceid_unavailable(devid))
+				return false;
+		}
 	}
 
 	return FF_LAYOUT_MIRROR_COUNT(lseg) != 0;
-- 
2.34.1

[PATCH 5/9] NFSv4/flexfiles: Read path updates for striped layouts

[Jonathan Curley]

Updates read path to calculate and use dss_id to direct IO to the
appropriate stripe DS.

Signed-off-by: Jonathan Curley <jcurley@purestorage.com>
---
 fs/nfs/flexfilelayout/flexfilelayout.c | 122 ++++++++++++++++++++-----
 1 file changed, 98 insertions(+), 24 deletions(-)

diff --git a/fs/nfs/flexfilelayout/flexfilelayout.c b/fs/nfs/flexfilelayout/flexfilelayout.c
index a2a3821f190c..79700c18762c 100644
--- a/fs/nfs/flexfilelayout/flexfilelayout.c
+++ b/fs/nfs/flexfilelayout/flexfilelayout.c
@@ -770,6 +770,7 @@ ff_layout_mark_ds_reachable(struct pnfs_layout_segment *lseg, u32 idx)
 static struct nfs4_pnfs_ds *
 ff_layout_choose_ds_for_read(struct pnfs_layout_segment *lseg,
 			     u32 start_idx, u32 *best_idx,
+			     u32 offset, u32 *dss_id,
 			     bool check_device)
 {
 	struct nfs4_ff_layout_segment *fls = FF_LAYOUT_LSEG(lseg);
@@ -780,12 +781,16 @@ ff_layout_choose_ds_for_read(struct pnfs_layout_segment *lseg,
 	/* mirrors are initially sorted by efficiency */
 	for (idx = start_idx; idx < fls->mirror_array_cnt; idx++) {
 		mirror = FF_LAYOUT_COMP(lseg, idx);
-		ds = nfs4_ff_layout_prepare_ds(lseg, mirror, 0, false);
+		*dss_id = nfs4_ff_layout_calc_dss_id(
+			fls->stripe_unit,
+			fls->mirror_array[idx]->dss_count,
+			offset);
+		ds = nfs4_ff_layout_prepare_ds(lseg, mirror, *dss_id, false);
 		if (!ds)
 			continue;
 
 		if (check_device &&
-		    nfs4_test_deviceid_unavailable(&mirror->dss[0].mirror_ds->id_node))
+		    nfs4_test_deviceid_unavailable(&mirror->dss[*dss_id].mirror_ds->id_node))
 			continue;
 
 		*best_idx = idx;
@@ -797,42 +802,52 @@ ff_layout_choose_ds_for_read(struct pnfs_layout_segment *lseg,
 
 static struct nfs4_pnfs_ds *
 ff_layout_choose_any_ds_for_read(struct pnfs_layout_segment *lseg,
-				 u32 start_idx, u32 *best_idx)
+				 u32 start_idx, u32 *best_idx,
+				 u32 offset, u32 *dss_id)
 {
-	return ff_layout_choose_ds_for_read(lseg, start_idx, best_idx, false);
+	return ff_layout_choose_ds_for_read(lseg, start_idx, best_idx,
+					    offset, dss_id, false);
 }
 
 static struct nfs4_pnfs_ds *
 ff_layout_choose_valid_ds_for_read(struct pnfs_layout_segment *lseg,
-				   u32 start_idx, u32 *best_idx)
+				   u32 start_idx, u32 *best_idx,
+				   u32 offset, u32 *dss_id)
 {
-	return ff_layout_choose_ds_for_read(lseg, start_idx, best_idx, true);
+	return ff_layout_choose_ds_for_read(lseg, start_idx, best_idx,
+					    offset, dss_id, true);
 }
 
 static struct nfs4_pnfs_ds *
 ff_layout_choose_best_ds_for_read(struct pnfs_layout_segment *lseg,
-				  u32 start_idx, u32 *best_idx)
+				  u32 start_idx, u32 *best_idx,
+				  u32 offset, u32 *dss_id)
 {
 	struct nfs4_pnfs_ds *ds;
 
-	ds = ff_layout_choose_valid_ds_for_read(lseg, start_idx, best_idx);
+	ds = ff_layout_choose_valid_ds_for_read(lseg, start_idx, best_idx,
+						offset, dss_id);
 	if (ds)
 		return ds;
-	return ff_layout_choose_any_ds_for_read(lseg, start_idx, best_idx);
+	return ff_layout_choose_any_ds_for_read(lseg, start_idx, best_idx,
+						offset, dss_id);
 }
 
 static struct nfs4_pnfs_ds *
 ff_layout_get_ds_for_read(struct nfs_pageio_descriptor *pgio,
-			  u32 *best_idx)
+			  u32 *best_idx,
+			  u32 offset,
+			  u32 *dss_id)
 {
 	struct pnfs_layout_segment *lseg = pgio->pg_lseg;
 	struct nfs4_pnfs_ds *ds;
 
 	ds = ff_layout_choose_best_ds_for_read(lseg, pgio->pg_mirror_idx,
-					       best_idx);
+					       best_idx, offset, dss_id);
 	if (ds || !pgio->pg_mirror_idx)
 		return ds;
-	return ff_layout_choose_best_ds_for_read(lseg, 0, best_idx);
+	return ff_layout_choose_best_ds_for_read(lseg, 0, best_idx,
+						 offset, dss_id);
 }
 
 static void
@@ -851,6 +866,56 @@ ff_layout_pg_get_read(struct nfs_pageio_descriptor *pgio,
 	}
 }
 
+static bool
+ff_layout_lseg_is_striped(const struct nfs4_ff_layout_segment *fls)
+{
+	return fls->mirror_array[0]->dss_count > 1;
+}
+
+/*
+ * ff_layout_pg_test(). Called by nfs_can_coalesce_requests()
+ *
+ * Return 0 if @req cannot be coalesced into @pgio, otherwise return the number
+ * of bytes (maximum @req->wb_bytes) that can be coalesced.
+ */
+static size_t
+ff_layout_pg_test(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev,
+		  struct nfs_page *req)
+{
+	unsigned int size;
+	u64 p_stripe, r_stripe;
+	u32 stripe_offset;
+	u64 segment_offset = pgio->pg_lseg->pls_range.offset;
+	u32 stripe_unit = FF_LAYOUT_LSEG(pgio->pg_lseg)->stripe_unit;
+
+	/* calls nfs_generic_pg_test */
+	size = pnfs_generic_pg_test(pgio, prev, req);
+	if (!size)
+		return 0;
+	else if (!ff_layout_lseg_is_striped(FF_LAYOUT_LSEG(pgio->pg_lseg)))
+		return size;
+
+	/* see if req and prev are in the same stripe */
+	if (prev) {
+		p_stripe = (u64)req_offset(prev) - segment_offset;
+		r_stripe = (u64)req_offset(req) - segment_offset;
+		do_div(p_stripe, stripe_unit);
+		do_div(r_stripe, stripe_unit);
+
+		if (p_stripe != r_stripe)
+			return 0;
+	}
+
+	/* calculate remaining bytes in the current stripe */
+	div_u64_rem((u64)req_offset(req) - segment_offset,
+			stripe_unit,
+			&stripe_offset);
+	WARN_ON_ONCE(stripe_offset > stripe_unit);
+	if (stripe_offset >= stripe_unit)
+		return 0;
+	return min(stripe_unit - (unsigned int)stripe_offset, size);
+}
+
 static void
 ff_layout_pg_init_read(struct nfs_pageio_descriptor *pgio,
 			struct nfs_page *req)
@@ -858,7 +923,7 @@ ff_layout_pg_init_read(struct nfs_pageio_descriptor *pgio,
 	struct nfs_pgio_mirror *pgm;
 	struct nfs4_ff_layout_mirror *mirror;
 	struct nfs4_pnfs_ds *ds;
-	u32 ds_idx;
+	u32 ds_idx, dss_id;
 
 	if (NFS_SERVER(pgio->pg_inode)->flags &
 			(NFS_MOUNT_SOFT|NFS_MOUNT_SOFTERR))
@@ -879,7 +944,8 @@ ff_layout_pg_init_read(struct nfs_pageio_descriptor *pgio,
 	/* Reset wb_nio, since getting layout segment was successful */
 	req->wb_nio = 0;
 
-	ds = ff_layout_get_ds_for_read(pgio, &ds_idx);
+	ds = ff_layout_get_ds_for_read(pgio, &ds_idx,
+				       req_offset(req), &dss_id);
 	if (!ds) {
 		if (!ff_layout_no_fallback_to_mds(pgio->pg_lseg))
 			goto out_mds;
@@ -891,7 +957,7 @@ ff_layout_pg_init_read(struct nfs_pageio_descriptor *pgio,
 
 	mirror = FF_LAYOUT_COMP(pgio->pg_lseg, ds_idx);
 	pgm = &pgio->pg_mirrors[0];
-	pgm->pg_bsize = mirror->dss[0].mirror_ds->ds_versions[0].rsize;
+	pgm->pg_bsize = mirror->dss[dss_id].mirror_ds->ds_versions[0].rsize;
 
 	pgio->pg_mirror_idx = ds_idx;
 	return;
@@ -1029,7 +1095,7 @@ ff_layout_pg_get_mirror_write(struct nfs_pageio_descriptor *desc, u32 idx)
 
 static const struct nfs_pageio_ops ff_layout_pg_read_ops = {
 	.pg_init = ff_layout_pg_init_read,
-	.pg_test = pnfs_generic_pg_test,
+	.pg_test = ff_layout_pg_test,
 	.pg_doio = pnfs_generic_pg_readpages,
 	.pg_cleanup = pnfs_generic_pg_cleanup,
 };
@@ -1084,8 +1150,10 @@ static void ff_layout_resend_pnfs_read(struct nfs_pgio_header *hdr)
 {
 	u32 idx = hdr->pgio_mirror_idx + 1;
 	u32 new_idx = 0;
+	u32 dss_id = 0;
 
-	if (ff_layout_choose_any_ds_for_read(hdr->lseg, idx, &new_idx))
+	if (ff_layout_choose_any_ds_for_read(hdr->lseg, idx, &new_idx,
+					     hdr->args.offset, &dss_id))
 		ff_layout_send_layouterror(hdr->lseg);
 	else
 		pnfs_error_mark_layout_for_return(hdr->inode, hdr->lseg);
@@ -1879,26 +1947,31 @@ ff_layout_read_pagelist(struct nfs_pgio_header *hdr)
 	u32 idx = hdr->pgio_mirror_idx;
 	int vers;
 	struct nfs_fh *fh;
+	u32 dss_id;
 
 	dprintk("--> %s ino %lu pgbase %u req %zu@%llu\n",
 		__func__, hdr->inode->i_ino,
 		hdr->args.pgbase, (size_t)hdr->args.count, offset);
 
 	mirror = FF_LAYOUT_COMP(lseg, idx);
-	ds = nfs4_ff_layout_prepare_ds(lseg, mirror, 0, false);
+	dss_id = nfs4_ff_layout_calc_dss_id(
+		FF_LAYOUT_LSEG(lseg)->stripe_unit,
+		mirror->dss_count,
+		offset);
+	ds = nfs4_ff_layout_prepare_ds(lseg, mirror, dss_id, false);
 	if (!ds)
 		goto out_failed;
 
 	ds_clnt = nfs4_ff_find_or_create_ds_client(mirror, ds->ds_clp,
-						   hdr->inode, 0);
+						   hdr->inode, dss_id);
 	if (IS_ERR(ds_clnt))
 		goto out_failed;
 
-	ds_cred = ff_layout_get_ds_cred(mirror, &lseg->pls_range, hdr->cred, 0);
+	ds_cred = ff_layout_get_ds_cred(mirror, &lseg->pls_range, hdr->cred, dss_id);
 	if (!ds_cred)
 		goto out_failed;
 
-	vers = nfs4_ff_layout_ds_version(mirror, 0);
+	vers = nfs4_ff_layout_ds_version(mirror, dss_id);
 
 	dprintk("%s USE DS: %s cl_count %d vers %d\n", __func__,
 		ds->ds_remotestr, refcount_read(&ds->ds_clp->cl_count), vers);
@@ -1906,11 +1979,11 @@ ff_layout_read_pagelist(struct nfs_pgio_header *hdr)
 	hdr->pgio_done_cb = ff_layout_read_done_cb;
 	refcount_inc(&ds->ds_clp->cl_count);
 	hdr->ds_clp = ds->ds_clp;
-	fh = nfs4_ff_layout_select_ds_fh(mirror, 0);
+	fh = nfs4_ff_layout_select_ds_fh(mirror, dss_id);
 	if (fh)
 		hdr->args.fh = fh;
 
-	nfs4_ff_layout_select_ds_stateid(mirror, 0, &hdr->args.stateid);
+	nfs4_ff_layout_select_ds_stateid(mirror, dss_id, &hdr->args.stateid);
 
 	/*
 	 * Note that if we ever decide to split across DSes,
@@ -1920,7 +1993,8 @@ ff_layout_read_pagelist(struct nfs_pgio_header *hdr)
 	hdr->mds_offset = offset;
 
 	/* Start IO accounting for local read */
-	localio = ff_local_open_fh(lseg, idx, 0, ds->ds_clp, ds_cred, fh, FMODE_READ);
+	localio = ff_local_open_fh(lseg, idx, dss_id, ds->ds_clp, ds_cred, fh,
+				FMODE_READ);
 	if (localio) {
 		hdr->task.tk_start = ktime_get();
 		ff_layout_read_record_layoutstats_start(&hdr->task, hdr);
-- 
2.34.1

[PATCH 6/9] NFSv4/flexfiles: Commit path updates for striped layouts

[Jonathan Curley]

Updates the commit path to be stripe aware. This required updating
the ds_commit_idx to be stripe aware.

ds_commit_idx == mirror_idx * dss_count + dss_id.

Updates code paths to utilize the new ds_commit_idx and derive dss_id
& mirror_idx where appropriate to contact the correct DS using the
corresponding parameters.

Signed-off-by: Jonathan Curley <jcurley@purestorage.com>
---
 fs/nfs/flexfilelayout/flexfilelayout.c | 49 +++++++++++++++++---------
 1 file changed, 33 insertions(+), 16 deletions(-)

diff --git a/fs/nfs/flexfilelayout/flexfilelayout.c b/fs/nfs/flexfilelayout/flexfilelayout.c
index 79700c18762c..b0d870359536 100644
--- a/fs/nfs/flexfilelayout/flexfilelayout.c
+++ b/fs/nfs/flexfilelayout/flexfilelayout.c
@@ -605,6 +605,26 @@ ff_layout_free_lseg(struct pnfs_layout_segment *lseg)
 	_ff_layout_free_lseg(fls);
 }
 
+static u32 calc_mirror_idx_from_commit(struct pnfs_layout_segment *lseg,
+				       u32 commit_index)
+{
+	struct nfs4_ff_layout_segment *flseg = FF_LAYOUT_LSEG(lseg);
+	u32 mirror_idx = commit_index;
+
+	do_div(mirror_idx, flseg->mirror_array[0]->dss_count);
+
+	return mirror_idx;
+}
+
+static u32 calc_dss_id_from_commit(struct pnfs_layout_segment *lseg,
+				   u32 commit_index)
+{
+	struct nfs4_ff_layout_segment *flseg = FF_LAYOUT_LSEG(lseg);
+	u32 mirror_idx = commit_index;
+
+	return do_div(mirror_idx, flseg->mirror_array[0]->dss_count);
+}
+
 static void
 nfs4_ff_start_busy_timer(struct nfs4_ff_busy_timer *timer, ktime_t now)
 {
@@ -2094,20 +2114,15 @@ ff_layout_write_pagelist(struct nfs_pgio_header *hdr, int sync)
 	return PNFS_NOT_ATTEMPTED;
 }
 
-static u32 calc_ds_index_from_commit(struct pnfs_layout_segment *lseg, u32 i)
-{
-	return i;
-}
-
 static struct nfs_fh *
-select_ds_fh_from_commit(struct pnfs_layout_segment *lseg, u32 i)
+select_ds_fh_from_commit(struct pnfs_layout_segment *lseg, u32 i, u32 dss_id)
 {
 	struct nfs4_ff_layout_segment *flseg = FF_LAYOUT_LSEG(lseg);
 
 	/* FIXME: Assume that there is only one NFS version available
 	 * for the DS.
 	 */
-	return &flseg->mirror_array[i]->dss[0].fh_versions[0];
+	return &flseg->mirror_array[i]->dss[dss_id].fh_versions[0];
 }
 
 static int ff_layout_initiate_commit(struct nfs_commit_data *data, int how)
@@ -2118,7 +2133,7 @@ static int ff_layout_initiate_commit(struct nfs_commit_data *data, int how)
 	struct nfsd_file *localio;
 	struct nfs4_ff_layout_mirror *mirror;
 	const struct cred *ds_cred;
-	u32 idx;
+	u32 idx, dss_id;
 	int vers, ret;
 	struct nfs_fh *fh;
 
@@ -2126,22 +2141,23 @@ static int ff_layout_initiate_commit(struct nfs_commit_data *data, int how)
 	    test_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags)))
 		goto out_err;
 
-	idx = calc_ds_index_from_commit(lseg, data->ds_commit_index);
+	idx = calc_mirror_idx_from_commit(lseg, data->ds_commit_index);
 	mirror = FF_LAYOUT_COMP(lseg, idx);
-	ds = nfs4_ff_layout_prepare_ds(lseg, mirror, 0, true);
+	dss_id = calc_dss_id_from_commit(lseg, data->ds_commit_index);
+	ds = nfs4_ff_layout_prepare_ds(lseg, mirror, dss_id, true);
 	if (!ds)
 		goto out_err;
 
 	ds_clnt = nfs4_ff_find_or_create_ds_client(mirror, ds->ds_clp,
-						   data->inode, 0);
+						   data->inode, dss_id);
 	if (IS_ERR(ds_clnt))
 		goto out_err;
 
-	ds_cred = ff_layout_get_ds_cred(mirror, &lseg->pls_range, data->cred, 0);
+	ds_cred = ff_layout_get_ds_cred(mirror, &lseg->pls_range, data->cred, dss_id);
 	if (!ds_cred)
 		goto out_err;
 
-	vers = nfs4_ff_layout_ds_version(mirror, 0);
+	vers = nfs4_ff_layout_ds_version(mirror, dss_id);
 
 	dprintk("%s ino %lu, how %d cl_count %d vers %d\n", __func__,
 		data->inode->i_ino, how, refcount_read(&ds->ds_clp->cl_count),
@@ -2150,12 +2166,12 @@ static int ff_layout_initiate_commit(struct nfs_commit_data *data, int how)
 	data->cred = ds_cred;
 	refcount_inc(&ds->ds_clp->cl_count);
 	data->ds_clp = ds->ds_clp;
-	fh = select_ds_fh_from_commit(lseg, data->ds_commit_index);
+	fh = select_ds_fh_from_commit(lseg, idx, dss_id);
 	if (fh)
 		data->args.fh = fh;
 
 	/* Start IO accounting for local commit */
-	localio = ff_local_open_fh(lseg, idx, 0, ds->ds_clp, ds_cred, fh,
+	localio = ff_local_open_fh(lseg, idx, dss_id, ds->ds_clp, ds_cred, fh,
 				   FMODE_READ|FMODE_WRITE);
 	if (localio) {
 		data->task.tk_start = ktime_get();
@@ -2259,8 +2275,9 @@ ff_layout_setup_ds_info(struct pnfs_ds_commit_info *fl_cinfo,
 	struct nfs4_ff_layout_segment *flseg = FF_LAYOUT_LSEG(lseg);
 	struct inode *inode = lseg->pls_layout->plh_inode;
 	struct pnfs_commit_array *array, *new;
+	u32 size = flseg->mirror_array_cnt * flseg->mirror_array[0]->dss_count;
 
-	new = pnfs_alloc_commit_array(flseg->mirror_array_cnt,
+	new = pnfs_alloc_commit_array(size,
 				      nfs_io_gfp_mask());
 	if (new) {
 		spin_lock(&inode->i_lock);
-- 
2.34.1

[PATCH 7/9] NFSv4/flexfiles: Write path updates for striped layouts

[Jonathan Curley]

Updates write path to calculate and use dss_id to direct IO to the
appropriate stripe DS.

Signed-off-by: Jonathan Curley <jcurley@purestorage.com>
---
 fs/nfs/flexfilelayout/flexfilelayout.c | 42 ++++++++++++++++++--------
 1 file changed, 30 insertions(+), 12 deletions(-)

diff --git a/fs/nfs/flexfilelayout/flexfilelayout.c b/fs/nfs/flexfilelayout/flexfilelayout.c
index b0d870359536..696589d191e5 100644
--- a/fs/nfs/flexfilelayout/flexfilelayout.c
+++ b/fs/nfs/flexfilelayout/flexfilelayout.c
@@ -605,6 +605,14 @@ ff_layout_free_lseg(struct pnfs_layout_segment *lseg)
 	_ff_layout_free_lseg(fls);
 }
 
+static u32 calc_commit_idx(struct pnfs_layout_segment *lseg,
+			   u32 mirror_idx, u32 dss_id)
+{
+	struct nfs4_ff_layout_segment *flseg = FF_LAYOUT_LSEG(lseg);
+
+	return (mirror_idx * flseg->mirror_array[0]->dss_count) + dss_id;
+}
+
 static u32 calc_mirror_idx_from_commit(struct pnfs_layout_segment *lseg,
 				       u32 commit_index)
 {
@@ -1014,7 +1022,7 @@ ff_layout_pg_init_write(struct nfs_pageio_descriptor *pgio,
 	struct nfs4_ff_layout_mirror *mirror;
 	struct nfs_pgio_mirror *pgm;
 	struct nfs4_pnfs_ds *ds;
-	u32 i;
+	u32 i, dss_id;
 
 retry:
 	pnfs_generic_pg_check_layout(pgio, req);
@@ -1039,7 +1047,12 @@ ff_layout_pg_init_write(struct nfs_pageio_descriptor *pgio,
 
 	for (i = 0; i < pgio->pg_mirror_count; i++) {
 		mirror = FF_LAYOUT_COMP(pgio->pg_lseg, i);
-		ds = nfs4_ff_layout_prepare_ds(pgio->pg_lseg, mirror, 0, true);
+		dss_id = nfs4_ff_layout_calc_dss_id(
+			FF_LAYOUT_LSEG(pgio->pg_lseg)->stripe_unit,
+			mirror->dss_count,
+			req_offset(req));
+		ds = nfs4_ff_layout_prepare_ds(pgio->pg_lseg, mirror,
+					       dss_id, true);
 		if (!ds) {
 			if (!ff_layout_no_fallback_to_mds(pgio->pg_lseg))
 				goto out_mds;
@@ -1049,7 +1062,7 @@ ff_layout_pg_init_write(struct nfs_pageio_descriptor *pgio,
 			goto retry;
 		}
 		pgm = &pgio->pg_mirrors[i];
-		pgm->pg_bsize = mirror->dss[0].mirror_ds->ds_versions[0].wsize;
+		pgm->pg_bsize = mirror->dss[dss_id].mirror_ds->ds_versions[0].wsize;
 	}
 
 	if (NFS_SERVER(pgio->pg_inode)->flags &
@@ -1122,7 +1135,7 @@ static const struct nfs_pageio_ops ff_layout_pg_read_ops = {
 
 static const struct nfs_pageio_ops ff_layout_pg_write_ops = {
 	.pg_init = ff_layout_pg_init_write,
-	.pg_test = pnfs_generic_pg_test,
+	.pg_test = ff_layout_pg_test,
 	.pg_doio = pnfs_generic_pg_writepages,
 	.pg_get_mirror_count = ff_layout_pg_get_mirror_count_write,
 	.pg_cleanup = pnfs_generic_pg_cleanup,
@@ -2051,22 +2064,27 @@ ff_layout_write_pagelist(struct nfs_pgio_header *hdr, int sync)
 	int vers;
 	struct nfs_fh *fh;
 	u32 idx = hdr->pgio_mirror_idx;
+	u32 dss_id;
 
 	mirror = FF_LAYOUT_COMP(lseg, idx);
-	ds = nfs4_ff_layout_prepare_ds(lseg, mirror, 0, true);
+	dss_id = nfs4_ff_layout_calc_dss_id(
+		FF_LAYOUT_LSEG(lseg)->stripe_unit,
+		mirror->dss_count,
+		offset);
+	ds = nfs4_ff_layout_prepare_ds(lseg, mirror, dss_id, true);
 	if (!ds)
 		goto out_failed;
 
 	ds_clnt = nfs4_ff_find_or_create_ds_client(mirror, ds->ds_clp,
-						   hdr->inode, 0);
+						   hdr->inode, dss_id);
 	if (IS_ERR(ds_clnt))
 		goto out_failed;
 
-	ds_cred = ff_layout_get_ds_cred(mirror, &lseg->pls_range, hdr->cred, 0);
+	ds_cred = ff_layout_get_ds_cred(mirror, &lseg->pls_range, hdr->cred, dss_id);
 	if (!ds_cred)
 		goto out_failed;
 
-	vers = nfs4_ff_layout_ds_version(mirror, 0);
+	vers = nfs4_ff_layout_ds_version(mirror, dss_id);
 
 	dprintk("%s ino %lu sync %d req %zu@%llu DS: %s cl_count %d vers %d\n",
 		__func__, hdr->inode->i_ino, sync, (size_t) hdr->args.count,
@@ -2076,12 +2094,12 @@ ff_layout_write_pagelist(struct nfs_pgio_header *hdr, int sync)
 	hdr->pgio_done_cb = ff_layout_write_done_cb;
 	refcount_inc(&ds->ds_clp->cl_count);
 	hdr->ds_clp = ds->ds_clp;
-	hdr->ds_commit_idx = idx;
-	fh = nfs4_ff_layout_select_ds_fh(mirror, 0);
+	hdr->ds_commit_idx = calc_commit_idx(lseg, idx, dss_id);
+	fh = nfs4_ff_layout_select_ds_fh(mirror, dss_id);
 	if (fh)
 		hdr->args.fh = fh;
 
-	nfs4_ff_layout_select_ds_stateid(mirror, 0, &hdr->args.stateid);
+	nfs4_ff_layout_select_ds_stateid(mirror, dss_id, &hdr->args.stateid);
 
 	/*
 	 * Note that if we ever decide to split across DSes,
@@ -2090,7 +2108,7 @@ ff_layout_write_pagelist(struct nfs_pgio_header *hdr, int sync)
 	hdr->args.offset = offset;
 
 	/* Start IO accounting for local write */
-	localio = ff_local_open_fh(lseg, idx, 0, ds->ds_clp, ds_cred, fh,
+	localio = ff_local_open_fh(lseg, idx, dss_id, ds->ds_clp, ds_cred, fh,
 				   FMODE_READ|FMODE_WRITE);
 	if (localio) {
 		hdr->task.tk_start = ktime_get();
-- 
2.34.1

[PATCH 8/9] NFSv4/flexfiles: Update layout stats & error paths for striped layouts

[Jonathan Curley]

Updates the layout stats logic to be stripe aware. Read and write
stats are accumulated on a per DS stripe basis. Also updates error
paths to use dss_id where appropraite.

Limitations:

1. The layout stats structure is still statically sized to 4 and there
is no deduplication logic for deviceids that may appear more than once
in a striped layout.

Signed-off-by: Jonathan Curley <jcurley@purestorage.com>
---
 fs/nfs/flexfilelayout/flexfilelayout.c | 300 +++++++++++++++++--------
 1 file changed, 201 insertions(+), 99 deletions(-)

diff --git a/fs/nfs/flexfilelayout/flexfilelayout.c b/fs/nfs/flexfilelayout/flexfilelayout.c
index 696589d191e5..24d0eef0b6a4 100644
--- a/fs/nfs/flexfilelayout/flexfilelayout.c
+++ b/fs/nfs/flexfilelayout/flexfilelayout.c
@@ -47,7 +47,7 @@ ff_layout_mirror_prepare_stats(struct pnfs_layout_hdr *lo,
 			       int dev_limit, enum nfs4_ff_op_type type);
 static void ff_layout_encode_ff_layoutupdate(struct xdr_stream *xdr,
 			      const struct nfs42_layoutstat_devinfo *devinfo,
-			      struct nfs4_ff_layout_mirror *mirror);
+			      struct nfs4_ff_layout_ds_stripe *dss_info);
 
 static struct pnfs_layout_hdr *
 ff_layout_alloc_layout_hdr(struct inode *inode, gfp_t gfp_flags)
@@ -657,6 +657,7 @@ nfs4_ff_end_busy_timer(struct nfs4_ff_busy_timer *timer, ktime_t now)
 
 static bool
 nfs4_ff_layoutstat_start_io(struct nfs4_ff_layout_mirror *mirror,
+			    u32 dss_id,
 			    struct nfs4_ff_layoutstat *layoutstat,
 			    ktime_t now)
 {
@@ -664,8 +665,8 @@ nfs4_ff_layoutstat_start_io(struct nfs4_ff_layout_mirror *mirror,
 	struct nfs4_flexfile_layout *ffl = FF_LAYOUT_FROM_HDR(mirror->layout);
 
 	nfs4_ff_start_busy_timer(&layoutstat->busy_timer, now);
-	if (!mirror->dss[0].start_time)
-		mirror->dss[0].start_time = now;
+	if (!mirror->dss[dss_id].start_time)
+		mirror->dss[dss_id].start_time = now;
 	if (mirror->report_interval != 0)
 		report_interval = (s64)mirror->report_interval * 1000LL;
 	else if (layoutstats_timer != 0)
@@ -715,13 +716,16 @@ nfs4_ff_layout_stat_io_update_completed(struct nfs4_ff_layoutstat *layoutstat,
 static void
 nfs4_ff_layout_stat_io_start_read(struct inode *inode,
 		struct nfs4_ff_layout_mirror *mirror,
+		u32 dss_id,
 		__u64 requested, ktime_t now)
 {
 	bool report;
 
 	spin_lock(&mirror->lock);
-	report = nfs4_ff_layoutstat_start_io(mirror, &mirror->dss[0].read_stat, now);
-	nfs4_ff_layout_stat_io_update_requested(&mirror->dss[0].read_stat, requested);
+	report = nfs4_ff_layoutstat_start_io(
+		mirror, dss_id, &mirror->dss[dss_id].read_stat, now);
+	nfs4_ff_layout_stat_io_update_requested(
+		&mirror->dss[dss_id].read_stat, requested);
 	set_bit(NFS4_FF_MIRROR_STAT_AVAIL, &mirror->flags);
 	spin_unlock(&mirror->lock);
 
@@ -732,11 +736,12 @@ nfs4_ff_layout_stat_io_start_read(struct inode *inode,
 static void
 nfs4_ff_layout_stat_io_end_read(struct rpc_task *task,
 		struct nfs4_ff_layout_mirror *mirror,
+		u32 dss_id,
 		__u64 requested,
 		__u64 completed)
 {
 	spin_lock(&mirror->lock);
-	nfs4_ff_layout_stat_io_update_completed(&mirror->dss[0].read_stat,
+	nfs4_ff_layout_stat_io_update_completed(&mirror->dss[dss_id].read_stat,
 			requested, completed,
 			ktime_get(), task->tk_start);
 	set_bit(NFS4_FF_MIRROR_STAT_AVAIL, &mirror->flags);
@@ -746,13 +751,20 @@ nfs4_ff_layout_stat_io_end_read(struct rpc_task *task,
 static void
 nfs4_ff_layout_stat_io_start_write(struct inode *inode,
 		struct nfs4_ff_layout_mirror *mirror,
+		u32 dss_id,
 		__u64 requested, ktime_t now)
 {
 	bool report;
 
 	spin_lock(&mirror->lock);
-	report = nfs4_ff_layoutstat_start_io(mirror, &mirror->dss[0].write_stat, now);
-	nfs4_ff_layout_stat_io_update_requested(&mirror->dss[0].write_stat, requested);
+	report = nfs4_ff_layoutstat_start_io(
+		mirror,
+		dss_id,
+		&mirror->dss[dss_id].write_stat,
+		now);
+	nfs4_ff_layout_stat_io_update_requested(
+		&mirror->dss[dss_id].write_stat,
+		requested);
 	set_bit(NFS4_FF_MIRROR_STAT_AVAIL, &mirror->flags);
 	spin_unlock(&mirror->lock);
 
@@ -763,6 +775,7 @@ nfs4_ff_layout_stat_io_start_write(struct inode *inode,
 static void
 nfs4_ff_layout_stat_io_end_write(struct rpc_task *task,
 		struct nfs4_ff_layout_mirror *mirror,
+		u32 dss_id,
 		__u64 requested,
 		__u64 completed,
 		enum nfs3_stable_how committed)
@@ -771,25 +784,25 @@ nfs4_ff_layout_stat_io_end_write(struct rpc_task *task,
 		requested = completed = 0;
 
 	spin_lock(&mirror->lock);
-	nfs4_ff_layout_stat_io_update_completed(&mirror->dss[0].write_stat,
+	nfs4_ff_layout_stat_io_update_completed(&mirror->dss[dss_id].write_stat,
 			requested, completed, ktime_get(), task->tk_start);
 	set_bit(NFS4_FF_MIRROR_STAT_AVAIL, &mirror->flags);
 	spin_unlock(&mirror->lock);
 }
 
 static void
-ff_layout_mark_ds_unreachable(struct pnfs_layout_segment *lseg, u32 idx)
+ff_layout_mark_ds_unreachable(struct pnfs_layout_segment *lseg, u32 idx, u32 dss_id)
 {
-	struct nfs4_deviceid_node *devid = FF_LAYOUT_DEVID_NODE(lseg, idx, 0);
+	struct nfs4_deviceid_node *devid = FF_LAYOUT_DEVID_NODE(lseg, idx, dss_id);
 
 	if (devid)
 		nfs4_mark_deviceid_unavailable(devid);
 }
 
 static void
-ff_layout_mark_ds_reachable(struct pnfs_layout_segment *lseg, u32 idx)
+ff_layout_mark_ds_reachable(struct pnfs_layout_segment *lseg, u32 idx, u32 dss_id)
 {
-	struct nfs4_deviceid_node *devid = FF_LAYOUT_DEVID_NODE(lseg, idx, 0);
+	struct nfs4_deviceid_node *devid = FF_LAYOUT_DEVID_NODE(lseg, idx, dss_id);
 
 	if (devid)
 		nfs4_mark_deviceid_available(devid);
@@ -1222,11 +1235,11 @@ static int ff_layout_async_handle_error_v4(struct rpc_task *task,
 					   struct nfs4_state *state,
 					   struct nfs_client *clp,
 					   struct pnfs_layout_segment *lseg,
-					   u32 idx)
+					   u32 idx, u32 dss_id)
 {
 	struct pnfs_layout_hdr *lo = lseg->pls_layout;
 	struct inode *inode = lo->plh_inode;
-	struct nfs4_deviceid_node *devid = FF_LAYOUT_DEVID_NODE(lseg, idx, 0);
+	struct nfs4_deviceid_node *devid = FF_LAYOUT_DEVID_NODE(lseg, idx, dss_id);
 	struct nfs4_slot_table *tbl = &clp->cl_session->fc_slot_table;
 
 	switch (op_status) {
@@ -1323,9 +1336,9 @@ static int ff_layout_async_handle_error_v3(struct rpc_task *task,
 					   u32 op_status,
 					   struct nfs_client *clp,
 					   struct pnfs_layout_segment *lseg,
-					   u32 idx)
+					   u32 idx, u32 dss_id)
 {
-	struct nfs4_deviceid_node *devid = FF_LAYOUT_DEVID_NODE(lseg, idx, 0);
+	struct nfs4_deviceid_node *devid = FF_LAYOUT_DEVID_NODE(lseg, idx, dss_id);
 
 	switch (op_status) {
 	case NFS_OK:
@@ -1389,12 +1402,17 @@ static int ff_layout_async_handle_error(struct rpc_task *task,
 					struct nfs4_state *state,
 					struct nfs_client *clp,
 					struct pnfs_layout_segment *lseg,
-					u32 idx)
+					u32 idx, u32 offset)
 {
 	int vers = clp->cl_nfs_mod->rpc_vers->number;
+	struct nfs4_ff_layout_segment *flseg = FF_LAYOUT_LSEG(lseg);
+	u32 dss_id = nfs4_ff_layout_calc_dss_id(
+		flseg->stripe_unit,
+		flseg->mirror_array[idx]->dss_count,
+		offset);
 
 	if (task->tk_status >= 0) {
-		ff_layout_mark_ds_reachable(lseg, idx);
+		ff_layout_mark_ds_reachable(lseg, idx, dss_id);
 		return 0;
 	}
 
@@ -1405,10 +1423,10 @@ static int ff_layout_async_handle_error(struct rpc_task *task,
 	switch (vers) {
 	case 3:
 		return ff_layout_async_handle_error_v3(task, op_status, clp,
-						       lseg, idx);
+						       lseg, idx, dss_id);
 	case 4:
 		return ff_layout_async_handle_error_v4(task, op_status, state,
-						       clp, lseg, idx);
+						       clp, lseg, idx, dss_id);
 	default:
 		/* should never happen */
 		WARN_ON_ONCE(1);
@@ -1423,6 +1441,7 @@ static void ff_layout_io_track_ds_error(struct pnfs_layout_segment *lseg,
 	struct nfs4_ff_layout_mirror *mirror;
 	u32 status = *op_status;
 	int err;
+	u32 dss_id;
 
 	if (status == 0) {
 		switch (error) {
@@ -1454,8 +1473,11 @@ static void ff_layout_io_track_ds_error(struct pnfs_layout_segment *lseg,
 	}
 
 	mirror = FF_LAYOUT_COMP(lseg, idx);
+	dss_id = nfs4_ff_layout_calc_dss_id(FF_LAYOUT_LSEG(lseg)->stripe_unit,
+					    mirror->dss_count,
+					    offset);
 	err = ff_layout_track_ds_error(FF_LAYOUT_FROM_HDR(lseg->pls_layout),
-				       mirror, 0, offset, length, status, opnum,
+				       mirror, dss_id, offset, length, status, opnum,
 				       nfs_io_gfp_mask());
 
 	switch (status) {
@@ -1464,7 +1486,7 @@ static void ff_layout_io_track_ds_error(struct pnfs_layout_segment *lseg,
 	case NFS4ERR_PERM:
 		break;
 	case NFS4ERR_NXIO:
-		ff_layout_mark_ds_unreachable(lseg, idx);
+		ff_layout_mark_ds_unreachable(lseg, idx, dss_id);
 		/*
 		 * Don't return the layout if this is a read and we still
 		 * have layouts to try
@@ -1497,7 +1519,8 @@ static int ff_layout_read_done_cb(struct rpc_task *task,
 	err = ff_layout_async_handle_error(task, hdr->res.op_status,
 					   hdr->args.context->state,
 					   hdr->ds_clp, hdr->lseg,
-					   hdr->pgio_mirror_idx);
+					   hdr->pgio_mirror_idx,
+					   hdr->args.offset);
 
 	trace_nfs4_pnfs_read(hdr, err);
 	clear_bit(NFS_IOHDR_RESEND_PNFS, &hdr->flags);
@@ -1553,23 +1576,47 @@ ff_layout_set_layoutcommit(struct inode *inode,
 static void ff_layout_read_record_layoutstats_start(struct rpc_task *task,
 		struct nfs_pgio_header *hdr)
 {
+	struct nfs4_ff_layout_mirror *mirror;
+	u32 dss_id;
+
 	if (test_and_set_bit(NFS_IOHDR_STAT, &hdr->flags))
 		return;
-	nfs4_ff_layout_stat_io_start_read(hdr->inode,
-			FF_LAYOUT_COMP(hdr->lseg, hdr->pgio_mirror_idx),
-			hdr->args.count,
-			task->tk_start);
+
+	mirror = FF_LAYOUT_COMP(hdr->lseg, hdr->pgio_mirror_idx);
+	dss_id = nfs4_ff_layout_calc_dss_id(
+		FF_LAYOUT_LSEG(hdr->lseg)->stripe_unit,
+		mirror->dss_count,
+		hdr->args.offset);
+
+	nfs4_ff_layout_stat_io_start_read(
+		hdr->inode,
+		mirror,
+		dss_id,
+		hdr->args.count,
+		task->tk_start);
 }
 
 static void ff_layout_read_record_layoutstats_done(struct rpc_task *task,
 		struct nfs_pgio_header *hdr)
 {
+	struct nfs4_ff_layout_mirror *mirror;
+	u32 dss_id;
+
 	if (!test_and_clear_bit(NFS_IOHDR_STAT, &hdr->flags))
 		return;
-	nfs4_ff_layout_stat_io_end_read(task,
-			FF_LAYOUT_COMP(hdr->lseg, hdr->pgio_mirror_idx),
-			hdr->args.count,
-			hdr->res.count);
+
+	mirror = FF_LAYOUT_COMP(hdr->lseg, hdr->pgio_mirror_idx);
+	dss_id = nfs4_ff_layout_calc_dss_id(
+		FF_LAYOUT_LSEG(hdr->lseg)->stripe_unit,
+		mirror->dss_count,
+		hdr->args.offset);
+
+	nfs4_ff_layout_stat_io_end_read(
+		task,
+		mirror,
+		dss_id,
+		hdr->args.count,
+		hdr->res.count);
 	set_bit(NFS_LSEG_LAYOUTRETURN, &hdr->lseg->pls_flags);
 }
 
@@ -1671,7 +1718,8 @@ static int ff_layout_write_done_cb(struct rpc_task *task,
 	err = ff_layout_async_handle_error(task, hdr->res.op_status,
 					   hdr->args.context->state,
 					   hdr->ds_clp, hdr->lseg,
-					   hdr->pgio_mirror_idx);
+					   hdr->pgio_mirror_idx,
+					   hdr->args.offset);
 
 	trace_nfs4_pnfs_write(hdr, err);
 	clear_bit(NFS_IOHDR_RESEND_PNFS, &hdr->flags);
@@ -1709,9 +1757,10 @@ static int ff_layout_commit_done_cb(struct rpc_task *task,
 				     struct nfs_commit_data *data)
 {
 	int err;
+	u32 idx = calc_mirror_idx_from_commit(data->lseg, data->ds_commit_index);
 
 	if (task->tk_status < 0) {
-		ff_layout_io_track_ds_error(data->lseg, data->ds_commit_index,
+		ff_layout_io_track_ds_error(data->lseg, idx,
 					    data->args.offset, data->args.count,
 					    &data->res.op_status, OP_COMMIT,
 					    task->tk_status);
@@ -1719,7 +1768,7 @@ static int ff_layout_commit_done_cb(struct rpc_task *task,
 	}
 
 	err = ff_layout_async_handle_error(task, data->res.op_status,
-					   NULL, data->ds_clp, data->lseg,
+					   NULL, data->ds_clp, data->lseg, idx,
 					   data->ds_commit_index);
 
 	trace_nfs4_pnfs_commit_ds(data, err);
@@ -1739,30 +1788,54 @@ static int ff_layout_commit_done_cb(struct rpc_task *task,
 	}
 
 	ff_layout_set_layoutcommit(data->inode, data->lseg, data->lwb);
-
 	return 0;
 }
 
 static void ff_layout_write_record_layoutstats_start(struct rpc_task *task,
 		struct nfs_pgio_header *hdr)
 {
+	struct nfs4_ff_layout_mirror *mirror;
+	u32 dss_id;
+
 	if (test_and_set_bit(NFS_IOHDR_STAT, &hdr->flags))
 		return;
-	nfs4_ff_layout_stat_io_start_write(hdr->inode,
-			FF_LAYOUT_COMP(hdr->lseg, hdr->pgio_mirror_idx),
-			hdr->args.count,
-			task->tk_start);
+
+	mirror = FF_LAYOUT_COMP(hdr->lseg, hdr->pgio_mirror_idx);
+	dss_id = nfs4_ff_layout_calc_dss_id(
+		FF_LAYOUT_LSEG(hdr->lseg)->stripe_unit,
+		mirror->dss_count,
+		hdr->args.offset);
+
+	nfs4_ff_layout_stat_io_start_write(
+		hdr->inode,
+		mirror,
+		dss_id,
+		hdr->args.count,
+		task->tk_start);
 }
 
 static void ff_layout_write_record_layoutstats_done(struct rpc_task *task,
 		struct nfs_pgio_header *hdr)
 {
+	struct nfs4_ff_layout_mirror *mirror;
+	u32 dss_id;
+
 	if (!test_and_clear_bit(NFS_IOHDR_STAT, &hdr->flags))
 		return;
-	nfs4_ff_layout_stat_io_end_write(task,
-			FF_LAYOUT_COMP(hdr->lseg, hdr->pgio_mirror_idx),
-			hdr->args.count, hdr->res.count,
-			hdr->res.verf->committed);
+
+	mirror = FF_LAYOUT_COMP(hdr->lseg, hdr->pgio_mirror_idx);
+	dss_id = nfs4_ff_layout_calc_dss_id(
+		FF_LAYOUT_LSEG(hdr->lseg)->stripe_unit,
+		mirror->dss_count,
+		hdr->args.offset);
+
+	nfs4_ff_layout_stat_io_end_write(
+		task,
+		mirror,
+		dss_id,
+		hdr->args.count,
+		hdr->res.count,
+		hdr->res.verf->committed);
 	set_bit(NFS_LSEG_LAYOUTRETURN, &hdr->lseg->pls_flags);
 }
 
@@ -1845,10 +1918,16 @@ static void ff_layout_write_release(void *data)
 static void ff_layout_commit_record_layoutstats_start(struct rpc_task *task,
 		struct nfs_commit_data *cdata)
 {
+	u32 idx, dss_id;
+
 	if (test_and_set_bit(NFS_IOHDR_STAT, &cdata->flags))
 		return;
+
+	idx = calc_mirror_idx_from_commit(cdata->lseg, cdata->ds_commit_index);
+	dss_id = calc_dss_id_from_commit(cdata->lseg, cdata->ds_commit_index);
 	nfs4_ff_layout_stat_io_start_write(cdata->inode,
-			FF_LAYOUT_COMP(cdata->lseg, cdata->ds_commit_index),
+			FF_LAYOUT_COMP(cdata->lseg, idx),
+			dss_id,
 			0, task->tk_start);
 }
 
@@ -1857,6 +1936,7 @@ static void ff_layout_commit_record_layoutstats_done(struct rpc_task *task,
 {
 	struct nfs_page *req;
 	__u64 count = 0;
+	u32 idx, dss_id;
 
 	if (!test_and_clear_bit(NFS_IOHDR_STAT, &cdata->flags))
 		return;
@@ -1865,8 +1945,12 @@ static void ff_layout_commit_record_layoutstats_done(struct rpc_task *task,
 		list_for_each_entry(req, &cdata->pages, wb_list)
 			count += req->wb_bytes;
 	}
+
+	idx = calc_mirror_idx_from_commit(cdata->lseg, cdata->ds_commit_index);
+	dss_id = calc_dss_id_from_commit(cdata->lseg, cdata->ds_commit_index);
 	nfs4_ff_layout_stat_io_end_write(task,
-			FF_LAYOUT_COMP(cdata->lseg, cdata->ds_commit_index),
+			FF_LAYOUT_COMP(cdata->lseg, idx),
+			dss_id,
 			count, count, NFS_FILE_SYNC);
 	set_bit(NFS_LSEG_LAYOUTRETURN, &cdata->lseg->pls_flags);
 }
@@ -2253,25 +2337,28 @@ static void ff_layout_cancel_io(struct pnfs_layout_segment *lseg)
 	struct nfs4_pnfs_ds *ds;
 	struct nfs_client *ds_clp;
 	struct rpc_clnt *clnt;
-	u32 idx;
+	u32 idx, dss_id;
 
 	for (idx = 0; idx < flseg->mirror_array_cnt; idx++) {
 		mirror = flseg->mirror_array[idx];
-		mirror_ds = mirror->dss[0].mirror_ds;
-		if (IS_ERR_OR_NULL(mirror_ds))
-			continue;
-		ds = mirror->dss[0].mirror_ds->ds;
-		if (!ds)
-			continue;
-		ds_clp = ds->ds_clp;
-		if (!ds_clp)
-			continue;
-		clnt = ds_clp->cl_rpcclient;
-		if (!clnt)
-			continue;
-		if (!rpc_cancel_tasks(clnt, -EAGAIN, ff_layout_match_io, lseg))
-			continue;
-		rpc_clnt_disconnect(clnt);
+		for (dss_id = 0; dss_id < mirror->dss_count; dss_id++) {
+			mirror_ds = mirror->dss[dss_id].mirror_ds;
+			if (IS_ERR_OR_NULL(mirror_ds))
+				continue;
+			ds = mirror->dss[dss_id].mirror_ds->ds;
+			if (!ds)
+				continue;
+			ds_clp = ds->ds_clp;
+			if (!ds_clp)
+				continue;
+			clnt = ds_clp->cl_rpcclient;
+			if (!clnt)
+				continue;
+			if (!rpc_cancel_tasks(clnt, -EAGAIN,
+					      ff_layout_match_io, lseg))
+				continue;
+			rpc_clnt_disconnect(clnt);
+		}
 	}
 }
 
@@ -2659,11 +2746,11 @@ ff_layout_encode_io_latency(struct xdr_stream *xdr,
 static void
 ff_layout_encode_ff_layoutupdate(struct xdr_stream *xdr,
 			      const struct nfs42_layoutstat_devinfo *devinfo,
-			      struct nfs4_ff_layout_mirror *mirror)
+			      struct nfs4_ff_layout_ds_stripe *dss_info)
 {
 	struct nfs4_pnfs_ds_addr *da;
-	struct nfs4_pnfs_ds *ds = mirror->dss[0].mirror_ds->ds;
-	struct nfs_fh *fh = &mirror->dss[0].fh_versions[0];
+	struct nfs4_pnfs_ds *ds = dss_info->mirror_ds->ds;
+	struct nfs_fh *fh = &dss_info->fh_versions[0];
 	__be32 *p;
 
 	da = list_first_entry(&ds->ds_addrs, struct nfs4_pnfs_ds_addr, da_node);
@@ -2675,13 +2762,17 @@ ff_layout_encode_ff_layoutupdate(struct xdr_stream *xdr,
 	p = xdr_reserve_space(xdr, 4 + fh->size);
 	xdr_encode_opaque(p, fh->data, fh->size);
 	/* ff_io_latency4 read */
-	spin_lock(&mirror->lock);
-	ff_layout_encode_io_latency(xdr, &mirror->dss[0].read_stat.io_stat);
+	spin_lock(&dss_info->mirror->lock);
+	ff_layout_encode_io_latency(xdr,
+				    &dss_info->read_stat.io_stat);
 	/* ff_io_latency4 write */
-	ff_layout_encode_io_latency(xdr, &mirror->dss[0].write_stat.io_stat);
-	spin_unlock(&mirror->lock);
+	ff_layout_encode_io_latency(xdr,
+				    &dss_info->write_stat.io_stat);
+	spin_unlock(&dss_info->mirror->lock);
 	/* nfstime4 */
-	ff_layout_encode_nfstime(xdr, ktime_sub(ktime_get(), mirror->dss[0].start_time));
+	ff_layout_encode_nfstime(xdr,
+				 ktime_sub(ktime_get(),
+					   dss_info->start_time));
 	/* bool */
 	p = xdr_reserve_space(xdr, 4);
 	*p = cpu_to_be32(false);
@@ -2705,7 +2796,8 @@ ff_layout_encode_layoutstats(struct xdr_stream *xdr, const void *args,
 static void
 ff_layout_free_layoutstats(struct nfs4_xdr_opaque_data *opaque)
 {
-	struct nfs4_ff_layout_mirror *mirror = opaque->data;
+	struct nfs4_ff_layout_ds_stripe *dss_info = opaque->data;
+	struct nfs4_ff_layout_mirror *mirror = dss_info->mirror;
 
 	ff_layout_put_mirror(mirror);
 }
@@ -2722,37 +2814,47 @@ ff_layout_mirror_prepare_stats(struct pnfs_layout_hdr *lo,
 {
 	struct nfs4_flexfile_layout *ff_layout = FF_LAYOUT_FROM_HDR(lo);
 	struct nfs4_ff_layout_mirror *mirror;
+	struct nfs4_ff_layout_ds_stripe *dss_info;
 	struct nfs4_deviceid_node *dev;
-	int i = 0;
+	int i = 0, dss_id;
 
 	list_for_each_entry(mirror, &ff_layout->mirrors, mirrors) {
-		if (i >= dev_limit)
-			break;
-		if (IS_ERR_OR_NULL(mirror->dss[0].mirror_ds))
-			continue;
-		if (!test_and_clear_bit(NFS4_FF_MIRROR_STAT_AVAIL,
-					&mirror->flags) &&
-		    type != NFS4_FF_OP_LAYOUTRETURN)
-			continue;
-		/* mirror refcount put in cleanup_layoutstats */
-		if (!refcount_inc_not_zero(&mirror->ref))
-			continue;
-		dev = &mirror->dss[0].mirror_ds->id_node;
-		memcpy(&devinfo->dev_id, &dev->deviceid, NFS4_DEVICEID4_SIZE);
-		devinfo->offset = 0;
-		devinfo->length = NFS4_MAX_UINT64;
-		spin_lock(&mirror->lock);
-		devinfo->read_count = mirror->dss[0].read_stat.io_stat.ops_completed;
-		devinfo->read_bytes = mirror->dss[0].read_stat.io_stat.bytes_completed;
-		devinfo->write_count = mirror->dss[0].write_stat.io_stat.ops_completed;
-		devinfo->write_bytes = mirror->dss[0].write_stat.io_stat.bytes_completed;
-		spin_unlock(&mirror->lock);
-		devinfo->layout_type = LAYOUT_FLEX_FILES;
-		devinfo->ld_private.ops = &layoutstat_ops;
-		devinfo->ld_private.data = mirror;
-
-		devinfo++;
-		i++;
+		for (dss_id = 0; dss_id < mirror->dss_count; ++dss_id) {
+			dss_info = &mirror->dss[dss_id];
+			if (i >= dev_limit)
+				break;
+			if (IS_ERR_OR_NULL(dss_info->mirror_ds))
+				continue;
+			if (!test_and_clear_bit(NFS4_FF_MIRROR_STAT_AVAIL,
+						&mirror->flags) &&
+			    type != NFS4_FF_OP_LAYOUTRETURN)
+				continue;
+			/* mirror refcount put in cleanup_layoutstats */
+			if (!refcount_inc_not_zero(&mirror->ref))
+				continue;
+			dev = &dss_info->mirror_ds->id_node;
+			memcpy(&devinfo->dev_id,
+			       &dev->deviceid,
+			       NFS4_DEVICEID4_SIZE);
+			devinfo->offset = 0;
+			devinfo->length = NFS4_MAX_UINT64;
+			spin_lock(&mirror->lock);
+			devinfo->read_count =
+			    dss_info->read_stat.io_stat.ops_completed;
+			devinfo->read_bytes =
+			    dss_info->read_stat.io_stat.bytes_completed;
+			devinfo->write_count =
+			    dss_info->write_stat.io_stat.ops_completed;
+			devinfo->write_bytes =
+			    dss_info->write_stat.io_stat.bytes_completed;
+			spin_unlock(&mirror->lock);
+			devinfo->layout_type = LAYOUT_FLEX_FILES;
+			devinfo->ld_private.ops = &layoutstat_ops;
+			devinfo->ld_private.data = &mirror->dss[dss_id];
+
+			devinfo++;
+			i++;
+		}
 	}
 	return i;
 }
-- 
2.34.1

[PATCH 9/9] NFSv4/flexfiles: Add support for striped layouts

[Jonathan Curley]

Updates lseg creation path to parse and add striped layouts. Enable
support for striped layouts.

Limitations:

1. All mirrors must have the same number of stripes.

Signed-off-by: Jonathan Curley <jcurley@purestorage.com>
---
 fs/nfs/flexfilelayout/flexfilelayout.c | 247 ++++++++++++++++---------
 fs/nfs/flexfilelayout/flexfilelayout.h |   2 +
 2 files changed, 157 insertions(+), 92 deletions(-)

diff --git a/fs/nfs/flexfilelayout/flexfilelayout.c b/fs/nfs/flexfilelayout/flexfilelayout.c
index 24d0eef0b6a4..444267938081 100644
--- a/fs/nfs/flexfilelayout/flexfilelayout.c
+++ b/fs/nfs/flexfilelayout/flexfilelayout.c
@@ -177,18 +177,19 @@ ff_local_open_fh(struct pnfs_layout_segment *lseg, u32 ds_idx, u32 dss_id,
 #endif
 }
 
-static bool ff_mirror_match_fh(const struct nfs4_ff_layout_mirror *m1,
-		const struct nfs4_ff_layout_mirror *m2)
+static bool ff_dss_match_fh(const struct nfs4_ff_layout_ds_stripe *dss1,
+		const struct nfs4_ff_layout_ds_stripe *dss2)
 {
 	int i, j;
 
-	if (m1->dss[0].fh_versions_cnt != m2->dss[0].fh_versions_cnt)
+	if (dss1->fh_versions_cnt != dss2->fh_versions_cnt)
 		return false;
-	for (i = 0; i < m1->dss[0].fh_versions_cnt; i++) {
+
+	for (i = 0; i < dss1->fh_versions_cnt; i++) {
 		bool found_fh = false;
-		for (j = 0; j < m2->dss[0].fh_versions_cnt; j++) {
-			if (nfs_compare_fh(&m1->dss[0].fh_versions[i],
-					&m2->dss[0].fh_versions[j]) == 0) {
+		for (j = 0; j < dss2->fh_versions_cnt; j++) {
+			if (nfs_compare_fh(&dss1->fh_versions[i],
+					&dss2->fh_versions[j]) == 0) {
 				found_fh = true;
 				break;
 			}
@@ -199,6 +200,38 @@ static bool ff_mirror_match_fh(const struct nfs4_ff_layout_mirror *m1,
 	return true;
 }
 
+static bool ff_mirror_match_fh(const struct nfs4_ff_layout_mirror *m1,
+		const struct nfs4_ff_layout_mirror *m2)
+{
+	u32 dss_id;
+
+	if (m1->dss_count != m2->dss_count)
+		return false;
+
+	for (dss_id = 0; dss_id < m1->dss_count; dss_id++)
+		if (!ff_dss_match_fh(&m1->dss[dss_id], &m2->dss[dss_id]))
+			return false;
+
+	return true;
+}
+
+static bool ff_mirror_match_devid(const struct nfs4_ff_layout_mirror *m1,
+		const struct nfs4_ff_layout_mirror *m2)
+{
+	u32 dss_id;
+
+	if (m1->dss_count != m2->dss_count)
+		return false;
+
+	for (dss_id = 0; dss_id < m1->dss_count; dss_id++)
+		if (memcmp(&m1->dss[dss_id].devid,
+			   &m2->dss[dss_id].devid,
+			   sizeof(m1->dss[dss_id].devid)) != 0)
+			return false;
+
+	return true;
+}
+
 static struct nfs4_ff_layout_mirror *
 ff_layout_add_mirror(struct pnfs_layout_hdr *lo,
 		struct nfs4_ff_layout_mirror *mirror)
@@ -209,8 +242,7 @@ ff_layout_add_mirror(struct pnfs_layout_hdr *lo,
 
 	spin_lock(&inode->i_lock);
 	list_for_each_entry(pos, &ff_layout->mirrors, mirrors) {
-		if (memcmp(&mirror->dss[0].devid, &pos->dss[0].devid,
-			   sizeof(pos->dss[0].devid)) != 0)
+		if (!ff_mirror_match_devid(mirror, pos))
 			continue;
 		if (!ff_mirror_match_fh(mirror, pos))
 			continue;
@@ -241,13 +273,15 @@ ff_layout_remove_mirror(struct nfs4_ff_layout_mirror *mirror)
 static struct nfs4_ff_layout_mirror *ff_layout_alloc_mirror(gfp_t gfp_flags)
 {
 	struct nfs4_ff_layout_mirror *mirror;
+	u32 dss_id;
 
 	mirror = kzalloc(sizeof(*mirror), gfp_flags);
 	if (mirror != NULL) {
 		spin_lock_init(&mirror->lock);
 		refcount_set(&mirror->ref, 1);
 		INIT_LIST_HEAD(&mirror->mirrors);
-		nfs_localio_file_init(&mirror->dss[0].nfl);
+		for (dss_id = 0; dss_id < mirror->dss_count; dss_id++)
+			nfs_localio_file_init(&mirror->dss[dss_id].nfl);
 	}
 	return mirror;
 }
@@ -255,17 +289,19 @@ static struct nfs4_ff_layout_mirror *ff_layout_alloc_mirror(gfp_t gfp_flags)
 static void ff_layout_free_mirror(struct nfs4_ff_layout_mirror *mirror)
 {
 	const struct cred	*cred;
-	int dss_id = 0;
+	u32 dss_id;
 
 	ff_layout_remove_mirror(mirror);
 
-	kfree(mirror->dss[dss_id].fh_versions);
-	nfs_close_local_fh(&mirror->dss[dss_id].nfl);
-	cred = rcu_access_pointer(mirror->dss[dss_id].ro_cred);
-	put_cred(cred);
-	cred = rcu_access_pointer(mirror->dss[dss_id].rw_cred);
-	put_cred(cred);
-	nfs4_ff_layout_put_deviceid(mirror->dss[dss_id].mirror_ds);
+	for (dss_id = 0; dss_id < mirror->dss_count; dss_id++) {
+		kfree(mirror->dss[dss_id].fh_versions);
+		cred = rcu_access_pointer(mirror->dss[dss_id].ro_cred);
+		put_cred(cred);
+		cred = rcu_access_pointer(mirror->dss[dss_id].rw_cred);
+		put_cred(cred);
+		nfs_close_local_fh(&mirror->dss[dss_id].nfl);
+		nfs4_ff_layout_put_deviceid(mirror->dss[dss_id].mirror_ds);
+	}
 
 	kfree(mirror->dss);
 	kfree(mirror);
@@ -371,14 +407,24 @@ ff_layout_add_lseg(struct pnfs_layout_hdr *lo,
 			free_me);
 }
 
+static u32 ff_mirror_efficiency_sum(const struct nfs4_ff_layout_mirror *mirror)
+{
+	u32 dss_id, sum = 0;
+
+	for (dss_id = 0; dss_id < mirror->dss_count; dss_id++)
+		sum += mirror->dss[dss_id].efficiency;
+
+	return sum;
+}
+
 static void ff_layout_sort_mirrors(struct nfs4_ff_layout_segment *fls)
 {
 	int i, j;
 
 	for (i = 0; i < fls->mirror_array_cnt - 1; i++) {
 		for (j = i + 1; j < fls->mirror_array_cnt; j++)
-			if (fls->mirror_array[i]->dss[0].efficiency <
-			    fls->mirror_array[j]->dss[0].efficiency)
+			if (ff_mirror_efficiency_sum(fls->mirror_array[i]) <
+			    ff_mirror_efficiency_sum(fls->mirror_array[j]))
 				swap(fls->mirror_array[i],
 				     fls->mirror_array[j]);
 	}
@@ -398,6 +444,7 @@ ff_layout_alloc_lseg(struct pnfs_layout_hdr *lh,
 	u32 mirror_array_cnt;
 	__be32 *p;
 	int i, rc;
+	struct nfs4_ff_layout_ds_stripe *dss_info;
 
 	dprintk("--> %s\n", __func__);
 	scratch = alloc_page(gfp_flags);
@@ -440,17 +487,24 @@ ff_layout_alloc_lseg(struct pnfs_layout_hdr *lh,
 		kuid_t uid;
 		kgid_t gid;
 		u32 fh_count, id;
-		int j, dss_id = 0;
+		int j, dss_id;
 
 		rc = -EIO;
 		p = xdr_inline_decode(&stream, 4);
 		if (!p)
 			goto out_err_free;
 
-		dss_count = be32_to_cpup(p);
+		// Ensure all mirrors have same stripe count.
+		if (dss_count == 0)
+			dss_count = be32_to_cpup(p);
+		else if (dss_count != be32_to_cpup(p))
+			goto out_err_free;
+
+		if (dss_count > NFS4_FLEXFILE_LAYOUT_MAX_STRIPE_CNT ||
+		    dss_count == 0)
+			goto out_err_free;
 
-		/* FIXME: allow for striping? */
-		if (dss_count != 1)
+		if (dss_count > 1 && stripe_unit == 0)
 			goto out_err_free;
 
 		fls->mirror_array[i] = ff_layout_alloc_mirror(gfp_flags);
@@ -464,91 +518,100 @@ ff_layout_alloc_lseg(struct pnfs_layout_hdr *lh,
 		    kcalloc(dss_count, sizeof(struct nfs4_ff_layout_ds_stripe),
 			    gfp_flags);
 
-		/* deviceid */
-		rc = decode_deviceid(&stream, &fls->mirror_array[i]->dss[dss_id].devid);
-		if (rc)
-			goto out_err_free;
+		for (dss_id = 0; dss_id < dss_count; dss_id++) {
+			dss_info = &fls->mirror_array[i]->dss[dss_id];
+			dss_info->mirror = fls->mirror_array[i];
 
-		/* efficiency */
-		rc = -EIO;
-		p = xdr_inline_decode(&stream, 4);
-		if (!p)
-			goto out_err_free;
-		fls->mirror_array[i]->dss[dss_id].efficiency = be32_to_cpup(p);
+			/* deviceid */
+			rc = decode_deviceid(&stream, &dss_info->devid);
+			if (rc)
+				goto out_err_free;
 
-		/* stateid */
-		rc = decode_pnfs_stateid(&stream, &fls->mirror_array[i]->dss[dss_id].stateid);
-		if (rc)
-			goto out_err_free;
+			/* efficiency */
+			rc = -EIO;
+			p = xdr_inline_decode(&stream, 4);
+			if (!p)
+				goto out_err_free;
+			dss_info->efficiency = be32_to_cpup(p);
 
-		/* fh */
-		rc = -EIO;
-		p = xdr_inline_decode(&stream, 4);
-		if (!p)
-			goto out_err_free;
-		fh_count = be32_to_cpup(p);
+			/* stateid */
+			rc = decode_pnfs_stateid(&stream, &dss_info->stateid);
+			if (rc)
+				goto out_err_free;
 
-		fls->mirror_array[i]->dss[dss_id].fh_versions =
-		    kcalloc(fh_count, sizeof(struct nfs_fh),
-			    gfp_flags);
-		if (fls->mirror_array[i]->dss[dss_id].fh_versions == NULL) {
-			rc = -ENOMEM;
-			goto out_err_free;
-		}
+			/* fh */
+			rc = -EIO;
+			p = xdr_inline_decode(&stream, 4);
+			if (!p)
+				goto out_err_free;
+			fh_count = be32_to_cpup(p);
 
-		for (j = 0; j < fh_count; j++) {
-			rc = decode_nfs_fh(&stream,
-					   &fls->mirror_array[i]->dss[dss_id].fh_versions[j]);
+			dss_info->fh_versions =
+			    kcalloc(fh_count, sizeof(struct nfs_fh),
+				    gfp_flags);
+			if (dss_info->fh_versions == NULL) {
+				rc = -ENOMEM;
+				goto out_err_free;
+			}
+
+			for (j = 0; j < fh_count; j++) {
+				rc = decode_nfs_fh(&stream,
+						   &dss_info->fh_versions[j]);
+				if (rc)
+					goto out_err_free;
+			}
+
+			dss_info->fh_versions_cnt = fh_count;
+
+			/* user */
+			rc = decode_name(&stream, &id);
 			if (rc)
 				goto out_err_free;
-		}
 
-		fls->mirror_array[i]->dss[dss_id].fh_versions_cnt = fh_count;
+			uid = make_kuid(&init_user_ns, id);
 
-		/* user */
-		rc = decode_name(&stream, &id);
-		if (rc)
-			goto out_err_free;
+			/* group */
+			rc = decode_name(&stream, &id);
+			if (rc)
+				goto out_err_free;
 
-		uid = make_kuid(&init_user_ns, id);
+			gid = make_kgid(&init_user_ns, id);
 
-		/* group */
-		rc = decode_name(&stream, &id);
-		if (rc)
-			goto out_err_free;
+			if (gfp_flags & __GFP_FS)
+				kcred = prepare_kernel_cred(&init_task);
+			else {
+				unsigned int nofs_flags = memalloc_nofs_save();
 
-		gid = make_kgid(&init_user_ns, id);
+				kcred = prepare_kernel_cred(&init_task);
+				memalloc_nofs_restore(nofs_flags);
+			}
+			rc = -ENOMEM;
+			if (!kcred)
+				goto out_err_free;
+			kcred->fsuid = uid;
+			kcred->fsgid = gid;
+			cred = RCU_INITIALIZER(kcred);
 
-		if (gfp_flags & __GFP_FS)
-			kcred = prepare_kernel_cred(&init_task);
-		else {
-			unsigned int nofs_flags = memalloc_nofs_save();
-			kcred = prepare_kernel_cred(&init_task);
-			memalloc_nofs_restore(nofs_flags);
+			if (lgr->range.iomode == IOMODE_READ)
+				rcu_assign_pointer(dss_info->ro_cred, cred);
+			else
+				rcu_assign_pointer(dss_info->rw_cred, cred);
 		}
-		rc = -ENOMEM;
-		if (!kcred)
-			goto out_err_free;
-		kcred->fsuid = uid;
-		kcred->fsgid = gid;
-		cred = RCU_INITIALIZER(kcred);
-
-		if (lgr->range.iomode == IOMODE_READ)
-			rcu_assign_pointer(fls->mirror_array[i]->dss[dss_id].ro_cred, cred);
-		else
-			rcu_assign_pointer(fls->mirror_array[i]->dss[dss_id].rw_cred, cred);
 
 		mirror = ff_layout_add_mirror(lh, fls->mirror_array[i]);
 		if (mirror != fls->mirror_array[i]) {
-			/* swap cred ptrs so free_mirror will clean up old */
-			if (lgr->range.iomode == IOMODE_READ) {
-				cred = xchg(&mirror->dss[dss_id].ro_cred,
-					    fls->mirror_array[i]->dss[dss_id].ro_cred);
-				rcu_assign_pointer(fls->mirror_array[i]->dss[dss_id].ro_cred, cred);
-			} else {
-				cred = xchg(&mirror->dss[dss_id].rw_cred,
-					    fls->mirror_array[i]->dss[dss_id].rw_cred);
-				rcu_assign_pointer(fls->mirror_array[i]->dss[dss_id].rw_cred, cred);
+			for (dss_id = 0; dss_id < dss_count; dss_id++) {
+				dss_info = &fls->mirror_array[i]->dss[dss_id];
+				/* swap cred ptrs so free_mirror will clean up old */
+				if (lgr->range.iomode == IOMODE_READ) {
+					cred = xchg(&mirror->dss[dss_id].ro_cred,
+						    dss_info->ro_cred);
+					rcu_assign_pointer(dss_info->ro_cred, cred);
+				} else {
+					cred = xchg(&mirror->dss[dss_id].rw_cred,
+						    dss_info->rw_cred);
+					rcu_assign_pointer(dss_info->rw_cred, cred);
+				}
 			}
 			ff_layout_free_mirror(fls->mirror_array[i]);
 			fls->mirror_array[i] = mirror;
diff --git a/fs/nfs/flexfilelayout/flexfilelayout.h b/fs/nfs/flexfilelayout/flexfilelayout.h
index 142324d6d5c5..17a008c8e97c 100644
--- a/fs/nfs/flexfilelayout/flexfilelayout.h
+++ b/fs/nfs/flexfilelayout/flexfilelayout.h
@@ -21,6 +21,8 @@
  * due to network error etc. */
 #define NFS4_FLEXFILE_LAYOUT_MAX_MIRROR_CNT 4096
 
+#define NFS4_FLEXFILE_LAYOUT_MAX_STRIPE_CNT 4096
+
 /* LAYOUTSTATS report interval in ms */
 #define FF_LAYOUTSTATS_REPORT_INTERVAL (60000L)
 #define FF_LAYOUTSTATS_MAXDEV 4
-- 
2.34.1

Re: [PATCH 4/9] NFSv4/flexfiles: Update low level helper functions to be DS stripe aware.

[kernel test robot]

Hi Jonathan,

kernel test robot noticed the following build warnings:

[auto build test WARNING on v6.16]
[cannot apply to trondmy-nfs/linux-next v6.17-rc2 v6.17-rc1 linus/master next-20250819]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Jonathan-Curley/NFSv4-flexfiles-Remove-cred-local-variable-dependency/20250819-061041
base:   v6.16
patch link:    https://lore.kernel.org/r/20250818220750.47085-5-jcurley%40purestorage.com
patch subject: [PATCH 4/9] NFSv4/flexfiles: Update low level helper functions to be DS stripe aware.
config: powerpc-randconfig-002-20250820 (https://download.01.org/0day-ci/archive/20250820/202508200945.mrU2bex2-lkp@intel.com/config)
compiler: powerpc-linux-gcc (GCC) 8.5.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250820/202508200945.mrU2bex2-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202508200945.mrU2bex2-lkp@intel.com/

All warnings (new ones prefixed by >>):

>> Warning: fs/nfs/flexfilelayout/flexfilelayoutdev.c:374 function parameter 'dss_id' not described in 'nfs4_ff_layout_prepare_ds'

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki