Merge tag 'nfs-for-5.10-3' of git://git.linux-nfs.org/projects/anna/linux-nfs

Pull NFS client fixes from Anna Schumaker:
 "Here are a handful more bugfixes for 5.10.

  Unfortunately, we found some problems with the new READ_PLUS operation
  that aren't easy to fix. We've decided to disable this codepath
  through a Kconfig option for now, but a series of patches going into
  5.11 will clean up the code and fix the issues at the same time. This
  seemed like the best way to go about it.

  Summary:

   - Fix array overflow when flexfiles mirroring is enabled

   - Fix rpcrdma_inline_fixup() crash with new LISTXATTRS

   - Fix 5 second delay when doing inter-server copy

   - Disable READ_PLUS by default"

* tag 'nfs-for-5.10-3' of git://git.linux-nfs.org/projects/anna/linux-nfs:
  NFS: Disable READ_PLUS by default
  NFSv4.2: Fix 5 seconds delay when doing inter server copy
  NFS: Fix rpcrdma_inline_fixup() crash with new LISTXATTRS operation
  pNFS/flexfiles: Fix array overflow when flexfiles mirroring is enabled

8 files changed, 76 insertions, 26 deletions

diff --git a/fs/nfs/Kconfig b/fs/nfs/Kconfig
index 88e1763e02f3..e2a488d403a6 100644
--- a/fs/nfs/Kconfig
+++ b/fs/nfs/Kconfig
@@ -205,3 +205,12 @@ config NFS_DISABLE_UDP_SUPPORT
 	 Choose Y here to disable the use of NFS over UDP. NFS over UDP
 	 on modern networks (1Gb+) can lead to data corruption caused by
 	 fragmentation during high loads.
+
+config NFS_V4_2_READ_PLUS
+	bool "NFS: Enable support for the NFSv4.2 READ_PLUS operation"
+	depends on NFS_V4_2
+	default n
+	help
+	 This is intended for developers only. The READ_PLUS operation has
+	 been shown to have issues under specific conditions and should not
+	 be used in production.
diff --git a/fs/nfs/flexfilelayout/flexfilelayout.c b/fs/nfs/flexfilelayout/flexfilelayout.c
index a163533446fa..24bf5797f88a 100644
--- a/fs/nfs/flexfilelayout/flexfilelayout.c
+++ b/fs/nfs/flexfilelayout/flexfilelayout.c
@@ -838,7 +838,7 @@ 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, i;
+	u32 ds_idx;
 
 retry:
 	ff_layout_pg_check_layout(pgio, req);
@@ -864,11 +864,9 @@ retry:
 		goto retry;
 	}
 
-	for (i = 0; i < pgio->pg_mirror_count; i++) {
-		mirror = FF_LAYOUT_COMP(pgio->pg_lseg, i);
-		pgm = &pgio->pg_mirrors[i];
-		pgm->pg_bsize = mirror->mirror_ds->ds_versions[0].rsize;
-	}
+	mirror = FF_LAYOUT_COMP(pgio->pg_lseg, ds_idx);
+	pgm = &pgio->pg_mirrors[0];
+	pgm->pg_bsize = mirror->mirror_ds->ds_versions[0].rsize;
 
 	pgio->pg_mirror_idx = ds_idx;
 
@@ -985,6 +983,21 @@ out:
 	return 1;
 }
 
+static u32
+ff_layout_pg_set_mirror_write(struct nfs_pageio_descriptor *desc, u32 idx)
+{
+	u32 old = desc->pg_mirror_idx;
+
+	desc->pg_mirror_idx = idx;
+	return old;
+}
+
+static struct nfs_pgio_mirror *
+ff_layout_pg_get_mirror_write(struct nfs_pageio_descriptor *desc, u32 idx)
+{
+	return &desc->pg_mirrors[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,
@@ -998,6 +1011,8 @@ static const struct nfs_pageio_ops ff_layout_pg_write_ops = {
 	.pg_doio = pnfs_generic_pg_writepages,
 	.pg_get_mirror_count = ff_layout_pg_get_mirror_count_write,
 	.pg_cleanup = pnfs_generic_pg_cleanup,
+	.pg_get_mirror = ff_layout_pg_get_mirror_write,
+	.pg_set_mirror = ff_layout_pg_set_mirror_write,
 };
 
 static void ff_layout_reset_write(struct nfs_pgio_header *hdr, bool retry_pnfs)
diff --git a/fs/nfs/nfs42proc.c b/fs/nfs/nfs42proc.c
index 2b2211d1234e..4fc61e3d098d 100644
--- a/fs/nfs/nfs42proc.c
+++ b/fs/nfs/nfs42proc.c
@@ -1241,12 +1241,13 @@ static ssize_t _nfs42_proc_listxattrs(struct inode *inode, void *buf,
 		.rpc_resp	= &res,
 	};
 	u32 xdrlen;
-	int ret, np;
+	int ret, np, i;
 
 
+	ret = -ENOMEM;
 	res.scratch = alloc_page(GFP_KERNEL);
 	if (!res.scratch)
-		return -ENOMEM;
+		goto out;
 
 	xdrlen = nfs42_listxattr_xdrsize(buflen);
 	if (xdrlen > server->lxasize)
@@ -1254,9 +1255,12 @@ static ssize_t _nfs42_proc_listxattrs(struct inode *inode, void *buf,
 	np = xdrlen / PAGE_SIZE + 1;
 
 	pages = kcalloc(np, sizeof(struct page *), GFP_KERNEL);
-	if (pages == NULL) {
-		__free_page(res.scratch);
-		return -ENOMEM;
+	if (!pages)
+		goto out_free_scratch;
+	for (i = 0; i < np; i++) {
+		pages[i] = alloc_page(GFP_KERNEL);
+		if (!pages[i])
+			goto out_free_pages;
 	}
 
 	arg.xattr_pages = pages;
@@ -1271,14 +1275,15 @@ static ssize_t _nfs42_proc_listxattrs(struct inode *inode, void *buf,
 		*eofp = res.eof;
 	}
 
+out_free_pages:
 	while (--np >= 0) {
 		if (pages[np])
 			__free_page(pages[np]);
 	}
-
-	__free_page(res.scratch);
 	kfree(pages);
-
+out_free_scratch:
+	__free_page(res.scratch);
+out:
 	return ret;
 
 }
diff --git a/fs/nfs/nfs42xdr.c b/fs/nfs/nfs42xdr.c
index 6e060a88f98c..8432bd6b95f0 100644
--- a/fs/nfs/nfs42xdr.c
+++ b/fs/nfs/nfs42xdr.c
@@ -1528,7 +1528,6 @@ static void nfs4_xdr_enc_listxattrs(struct rpc_rqst *req,
 
 	rpc_prepare_reply_pages(req, args->xattr_pages, 0, args->count,
 	    hdr.replen);
-	req->rq_rcv_buf.flags |= XDRBUF_SPARSE_PAGES;
 
 	encode_nops(&hdr);
 }
diff --git a/fs/nfs/nfs4file.c b/fs/nfs/nfs4file.c
index 9d354de613da..57b3821d975a 100644
--- a/fs/nfs/nfs4file.c
+++ b/fs/nfs/nfs4file.c
@@ -377,10 +377,10 @@ static struct file *__nfs42_ssc_open(struct vfsmount *ss_mnt,
 		goto out_stateowner;
 
 	set_bit(NFS_SRV_SSC_COPY_STATE, &ctx->state->flags);
-	set_bit(NFS_OPEN_STATE, &ctx->state->flags);
 	memcpy(&ctx->state->open_stateid.other, &stateid->other,
 	       NFS4_STATEID_OTHER_SIZE);
 	update_open_stateid(ctx->state, stateid, NULL, filep->f_mode);
+	set_bit(NFS_OPEN_STATE, &ctx->state->flags);
 
 	nfs_file_set_open_context(filep, ctx);
 	put_nfs_open_context(ctx);
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 9e0ca9b2b210..e89468678ae1 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -5309,7 +5309,7 @@ static int nfs4_read_done(struct rpc_task *task, struct nfs_pgio_header *hdr)
 				    nfs4_read_done_cb(task, hdr);
 }
 
-#ifdef CONFIG_NFS_V4_2
+#if defined CONFIG_NFS_V4_2 && defined CONFIG_NFS_V4_2_READ_PLUS
 static void nfs42_read_plus_support(struct nfs_server *server, struct rpc_message *msg)
 {
 	if (server->caps & NFS_CAP_READ_PLUS)
diff --git a/fs/nfs/pagelist.c b/fs/nfs/pagelist.c
index 6985cacf4700..78c9c4bdef2b 100644
--- a/fs/nfs/pagelist.c
+++ b/fs/nfs/pagelist.c
@@ -31,13 +31,29 @@
 static struct kmem_cache *nfs_page_cachep;
 static const struct rpc_call_ops nfs_pgio_common_ops;
 
+static struct nfs_pgio_mirror *
+nfs_pgio_get_mirror(struct nfs_pageio_descriptor *desc, u32 idx)
+{
+	if (desc->pg_ops->pg_get_mirror)
+		return desc->pg_ops->pg_get_mirror(desc, idx);
+	return &desc->pg_mirrors[0];
+}
+
 struct nfs_pgio_mirror *
 nfs_pgio_current_mirror(struct nfs_pageio_descriptor *desc)
 {
-	return &desc->pg_mirrors[desc->pg_mirror_idx];
+	return nfs_pgio_get_mirror(desc, desc->pg_mirror_idx);
 }
 EXPORT_SYMBOL_GPL(nfs_pgio_current_mirror);
 
+static u32
+nfs_pgio_set_current_mirror(struct nfs_pageio_descriptor *desc, u32 idx)
+{
+	if (desc->pg_ops->pg_set_mirror)
+		return desc->pg_ops->pg_set_mirror(desc, idx);
+	return desc->pg_mirror_idx;
+}
+
 void nfs_pgheader_init(struct nfs_pageio_descriptor *desc,
 		       struct nfs_pgio_header *hdr,
 		       void (*release)(struct nfs_pgio_header *hdr))
@@ -1259,7 +1275,7 @@ static void nfs_pageio_error_cleanup(struct nfs_pageio_descriptor *desc)
 		return;
 
 	for (midx = 0; midx < desc->pg_mirror_count; midx++) {
-		mirror = &desc->pg_mirrors[midx];
+		mirror = nfs_pgio_get_mirror(desc, midx);
 		desc->pg_completion_ops->error_cleanup(&mirror->pg_list,
 				desc->pg_error);
 	}
@@ -1293,12 +1309,12 @@ int nfs_pageio_add_request(struct nfs_pageio_descriptor *desc,
 			goto out_failed;
 		}
 
-		desc->pg_mirror_idx = midx;
+		nfs_pgio_set_current_mirror(desc, midx);
 		if (!nfs_pageio_add_request_mirror(desc, dupreq))
 			goto out_cleanup_subreq;
 	}
 
-	desc->pg_mirror_idx = 0;
+	nfs_pgio_set_current_mirror(desc, 0);
 	if (!nfs_pageio_add_request_mirror(desc, req))
 		goto out_failed;
 
@@ -1320,10 +1336,12 @@ out_failed:
 static void nfs_pageio_complete_mirror(struct nfs_pageio_descriptor *desc,
 				       u32 mirror_idx)
 {
-	struct nfs_pgio_mirror *mirror = &desc->pg_mirrors[mirror_idx];
-	u32 restore_idx = desc->pg_mirror_idx;
+	struct nfs_pgio_mirror *mirror;
+	u32 restore_idx;
+
+	restore_idx = nfs_pgio_set_current_mirror(desc, mirror_idx);
+	mirror = nfs_pgio_current_mirror(desc);
 
-	desc->pg_mirror_idx = mirror_idx;
 	for (;;) {
 		nfs_pageio_doio(desc);
 		if (desc->pg_error < 0 || !mirror->pg_recoalesce)
@@ -1331,7 +1349,7 @@ static void nfs_pageio_complete_mirror(struct nfs_pageio_descriptor *desc,
 		if (!nfs_do_recoalesce(desc))
 			break;
 	}
-	desc->pg_mirror_idx = restore_idx;
+	nfs_pgio_set_current_mirror(desc, restore_idx);
 }
 
 /*
@@ -1405,7 +1423,7 @@ void nfs_pageio_cond_complete(struct nfs_pageio_descriptor *desc, pgoff_t index)
 	u32 midx;
 
 	for (midx = 0; midx < desc->pg_mirror_count; midx++) {
-		mirror = &desc->pg_mirrors[midx];
+		mirror = nfs_pgio_get_mirror(desc, midx);
 		if (!list_empty(&mirror->pg_list)) {
 			prev = nfs_list_entry(mirror->pg_list.prev);
 			if (index != prev->wb_index + 1) {
diff --git a/include/linux/nfs_page.h b/include/linux/nfs_page.h
index c32c15216da3..f0373a6cb5fb 100644
--- a/include/linux/nfs_page.h
+++ b/include/linux/nfs_page.h
@@ -55,6 +55,7 @@ struct nfs_page {
 	unsigned short		wb_nio;		/* Number of I/O attempts */
 };
 
+struct nfs_pgio_mirror;
 struct nfs_pageio_descriptor;
 struct nfs_pageio_ops {
 	void	(*pg_init)(struct nfs_pageio_descriptor *, struct nfs_page *);
@@ -64,6 +65,9 @@ struct nfs_pageio_ops {
 	unsigned int	(*pg_get_mirror_count)(struct nfs_pageio_descriptor *,
 				       struct nfs_page *);
 	void	(*pg_cleanup)(struct nfs_pageio_descriptor *);
+	struct nfs_pgio_mirror *
+		(*pg_get_mirror)(struct nfs_pageio_descriptor *, u32);
+	u32	(*pg_set_mirror)(struct nfs_pageio_descriptor *, u32);
 };
 
 struct nfs_rw_ops {