pNFS/flexfiles: Ensure pNFS allocation modes are consistent with nfsiod

Ensure that pNFS flexfile allocations in rpciod/nfsiod callbacks can
fail in low memory mode, so that the threads don't block and loop
forever.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

fs/nfs/flexfilelayout/flexfilelayout.c

@@ -663,7 +663,7 @@ nfs4_ff_layout_stat_io_start_read(struct inode *inode,
 	spin_unlock(&mirror->lock);
 
 	if (report)
-		pnfs_report_layoutstat(inode, GFP_KERNEL);
+		pnfs_report_layoutstat(inode, nfs_io_gfp_mask());
 }
 
 static void
@@ -694,7 +694,7 @@ nfs4_ff_layout_stat_io_start_write(struct inode *inode,
 	spin_unlock(&mirror->lock);
 
 	if (report)
-		pnfs_report_layoutstat(inode, GFP_KERNEL);
+		pnfs_report_layoutstat(inode, nfs_io_gfp_mask());
 }
 
 static void
@@ -806,13 +806,10 @@ ff_layout_pg_get_read(struct nfs_pageio_descriptor *pgio,
 		      bool strict_iomode)
 {
 	pnfs_put_lseg(pgio->pg_lseg);
-	pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
-					   nfs_req_openctx(req),
-					   req_offset(req),
-					   req->wb_bytes,
-					   IOMODE_READ,
-					   strict_iomode,
-					   GFP_KERNEL);
+	pgio->pg_lseg =
+		pnfs_update_layout(pgio->pg_inode, nfs_req_openctx(req),
+				   req_offset(req), req->wb_bytes, IOMODE_READ,
+				   strict_iomode, nfs_io_gfp_mask());
 	if (IS_ERR(pgio->pg_lseg)) {
 		pgio->pg_error = PTR_ERR(pgio->pg_lseg);
 		pgio->pg_lseg = NULL;
@@ -894,13 +891,10 @@ ff_layout_pg_init_write(struct nfs_pageio_descriptor *pgio,
 retry:
 	ff_layout_pg_check_layout(pgio, req);
 	if (!pgio->pg_lseg) {
-		pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
-						   nfs_req_openctx(req),
-						   req_offset(req),
-						   req->wb_bytes,
-						   IOMODE_RW,
-						   false,
-						   GFP_KERNEL);
+		pgio->pg_lseg =
+			pnfs_update_layout(pgio->pg_inode, nfs_req_openctx(req),
+					   req_offset(req), req->wb_bytes,
+					   IOMODE_RW, false, nfs_io_gfp_mask());
 		if (IS_ERR(pgio->pg_lseg)) {
 			pgio->pg_error = PTR_ERR(pgio->pg_lseg);
 			pgio->pg_lseg = NULL;
@@ -953,13 +947,10 @@ ff_layout_pg_get_mirror_count_write(struct nfs_pageio_descriptor *pgio,
 				    struct nfs_page *req)
 {
 	if (!pgio->pg_lseg) {
-		pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
-						   nfs_req_openctx(req),
-						   req_offset(req),
-						   req->wb_bytes,
-						   IOMODE_RW,
-						   false,
-						   GFP_KERNEL);
+		pgio->pg_lseg =
+			pnfs_update_layout(pgio->pg_inode, nfs_req_openctx(req),
+					   req_offset(req), req->wb_bytes,
+					   IOMODE_RW, false, nfs_io_gfp_mask());
 		if (IS_ERR(pgio->pg_lseg)) {
 			pgio->pg_error = PTR_ERR(pgio->pg_lseg);
 			pgio->pg_lseg = NULL;
@@ -1258,7 +1249,7 @@ 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,
-				       GFP_KERNEL);
+				       nfs_io_gfp_mask());
 
 	switch (status) {
 	case NFS4ERR_DELAY:
@@ -1973,7 +1964,8 @@ ff_layout_setup_ds_info(struct pnfs_ds_commit_info *fl_cinfo,
 	struct inode *inode = lseg->pls_layout->plh_inode;
 	struct pnfs_commit_array *array, *new;
 
-	new = pnfs_alloc_commit_array(flseg->mirror_array_cnt, GFP_KERNEL);
+	new = pnfs_alloc_commit_array(flseg->mirror_array_cnt,
+				      nfs_io_gfp_mask());
 	if (new) {
 		spin_lock(&inode->i_lock);
 		array = pnfs_add_commit_array(fl_cinfo, new, lseg);
@@ -2152,10 +2144,10 @@ ff_layout_prepare_layoutreturn(struct nfs4_layoutreturn_args *args)
 	struct nfs4_flexfile_layoutreturn_args *ff_args;
 	struct nfs4_flexfile_layout *ff_layout = FF_LAYOUT_FROM_HDR(args->layout);
 
-	ff_args = kmalloc(sizeof(*ff_args), GFP_KERNEL);
+	ff_args = kmalloc(sizeof(*ff_args), nfs_io_gfp_mask());
 	if (!ff_args)
 		goto out_nomem;
-	ff_args->pages[0] = alloc_page(GFP_KERNEL);
+	ff_args->pages[0] = alloc_page(nfs_io_gfp_mask());
 	if (!ff_args->pages[0])
 		goto out_nomem_free;
 
@@ -2193,7 +2185,7 @@ ff_layout_send_layouterror(struct pnfs_layout_segment *lseg)
 		return;
 
 	errors = kmalloc_array(NFS42_LAYOUTERROR_MAX, sizeof(*errors),
-			       GFP_KERNEL);
+			       nfs_io_gfp_mask());
 	if (errors != NULL) {
 		const struct nfs4_ff_layout_ds_err *pos;
 		size_t n = 0;
@@ -2445,7 +2437,7 @@ ff_layout_prepare_layoutstats(struct nfs42_layoutstat_args *args)
 
 	/* For now, send at most PNFS_LAYOUTSTATS_MAXDEV statistics */
 	args->devinfo = kmalloc_array(dev_count, sizeof(*args->devinfo),
-				      GFP_KERNEL);
+				      nfs_io_gfp_mask());
 	if (!args->devinfo)
 		return -ENOMEM;