Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/fs/nfs/write.c b/fs/nfs/write.c
index 586726a..52cab65 100644
--- a/fs/nfs/write.c
+++ b/fs/nfs/write.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * linux/fs/nfs/write.c
  *
@@ -26,6 +27,7 @@
 #include <linux/iversion.h>
 
 #include <linux/uaccess.h>
+#include <linux/sched/mm.h>
 
 #include "delegation.h"
 #include "internal.h"
@@ -55,6 +57,7 @@
 static const struct nfs_pgio_completion_ops nfs_async_write_completion_ops;
 static const struct nfs_commit_completion_ops nfs_commit_completion_ops;
 static const struct nfs_rw_ops nfs_rw_write_ops;
+static void nfs_inode_remove_request(struct nfs_page *req);
 static void nfs_clear_request_commit(struct nfs_page *req);
 static void nfs_init_cinfo_from_inode(struct nfs_commit_info *cinfo,
 				      struct inode *inode);
@@ -101,7 +104,7 @@
 
 static struct nfs_pgio_header *nfs_writehdr_alloc(void)
 {
-	struct nfs_pgio_header *p = mempool_alloc(nfs_wdata_mempool, GFP_NOIO);
+	struct nfs_pgio_header *p = mempool_alloc(nfs_wdata_mempool, GFP_KERNEL);
 
 	memset(p, 0, sizeof(*p));
 	p->rw_mode = FMODE_WRITE;
@@ -238,9 +241,15 @@
 }
 
 /* A writeback failed: mark the page as bad, and invalidate the page cache */
-static void nfs_set_pageerror(struct page *page)
+static void nfs_set_pageerror(struct address_space *mapping)
 {
-	nfs_zap_mapping(page_file_mapping(page)->host, page_file_mapping(page));
+	nfs_zap_mapping(mapping->host, mapping);
+}
+
+static void nfs_mapping_set_error(struct page *page, int error)
+{
+	SetPageError(page);
+	mapping_set_error(page_file_mapping(page), error);
 }
 
 /*
@@ -581,26 +590,15 @@
 	return ERR_PTR(ret);
 }
 
-static void nfs_write_error_remove_page(struct nfs_page *req)
+static void nfs_write_error(struct nfs_page *req, int error)
 {
+	nfs_set_pageerror(page_file_mapping(req->wb_page));
+	nfs_mapping_set_error(req->wb_page, error);
+	nfs_inode_remove_request(req);
 	nfs_end_page_writeback(req);
-	generic_error_remove_page(page_file_mapping(req->wb_page),
-				  req->wb_page);
 	nfs_release_request(req);
 }
 
-static bool
-nfs_error_is_fatal_on_server(int err)
-{
-	switch (err) {
-	case 0:
-	case -ERESTARTSYS:
-	case -EINTR:
-		return false;
-	}
-	return nfs_error_is_fatal(err);
-}
-
 /*
  * Find an associated nfs write request, and prepare to flush it out
  * May return an error if the user signalled nfs_wait_on_request().
@@ -621,31 +619,32 @@
 	nfs_set_page_writeback(page);
 	WARN_ON_ONCE(test_bit(PG_CLEAN, &req->wb_flags));
 
-	ret = 0;
 	/* If there is a fatal error that covers this write, just exit */
-	if (nfs_error_is_fatal_on_server(req->wb_context->error))
+	ret = pgio->pg_error;
+	if (nfs_error_is_fatal_on_server(ret))
 		goto out_launder;
 
+	ret = 0;
 	if (!nfs_pageio_add_request(pgio, req)) {
 		ret = pgio->pg_error;
 		/*
 		 * Remove the problematic req upon fatal errors on the server
 		 */
 		if (nfs_error_is_fatal(ret)) {
-			nfs_context_set_write_error(req->wb_context, ret);
 			if (nfs_error_is_fatal_on_server(ret))
 				goto out_launder;
-		}
+		} else
+			ret = -EAGAIN;
 		nfs_redirty_request(req);
-		ret = -EAGAIN;
+		pgio->pg_error = 0;
 	} else
 		nfs_add_stats(page_file_mapping(page)->host,
 				NFSIOS_WRITEPAGES, 1);
 out:
 	return ret;
 out_launder:
-	nfs_write_error_remove_page(req);
-	return ret;
+	nfs_write_error(req, ret);
+	return 0;
 }
 
 static int nfs_do_writepage(struct page *page, struct writeback_control *wbc,
@@ -657,7 +656,7 @@
 	ret = nfs_page_async_flush(pgio, page);
 	if (ret == -EAGAIN) {
 		redirty_page_for_writepage(wbc, page);
-		ret = 0;
+		ret = AOP_WRITEPAGE_ACTIVATE;
 	}
 	return ret;
 }
@@ -676,10 +675,11 @@
 	nfs_pageio_init_write(&pgio, inode, 0,
 				false, &nfs_async_write_completion_ops);
 	err = nfs_do_writepage(page, wbc, &pgio);
+	pgio.pg_error = 0;
 	nfs_pageio_complete(&pgio);
 	if (err < 0)
 		return err;
-	if (pgio.pg_error < 0)
+	if (nfs_error_is_fatal(pgio.pg_error))
 		return pgio.pg_error;
 	return 0;
 }
@@ -689,7 +689,8 @@
 	int ret;
 
 	ret = nfs_writepage_locked(page, wbc);
-	unlock_page(page);
+	if (ret != AOP_WRITEPAGE_ACTIVATE)
+		unlock_page(page);
 	return ret;
 }
 
@@ -698,7 +699,8 @@
 	int ret;
 
 	ret = nfs_do_writepage(page, wbc, data);
-	unlock_page(page);
+	if (ret != AOP_WRITEPAGE_ACTIVATE)
+		unlock_page(page);
 	return ret;
 }
 
@@ -711,11 +713,12 @@
 {
 	struct inode *inode = mapping->host;
 	struct nfs_pageio_descriptor pgio;
-	struct nfs_io_completion *ioc = nfs_io_completion_alloc(GFP_NOFS);
+	struct nfs_io_completion *ioc;
 	int err;
 
 	nfs_inc_stats(inode, NFSIOS_VFSWRITEPAGES);
 
+	ioc = nfs_io_completion_alloc(GFP_KERNEL);
 	if (ioc)
 		nfs_io_completion_init(ioc, nfs_io_completion_commit, inode);
 
@@ -723,13 +726,14 @@
 				&nfs_async_write_completion_ops);
 	pgio.pg_io_completion = ioc;
 	err = write_cache_pages(mapping, wbc, nfs_writepages_callback, &pgio);
+	pgio.pg_error = 0;
 	nfs_pageio_complete(&pgio);
 	nfs_io_completion_put(ioc);
 
 	if (err < 0)
 		goto out_err;
 	err = pgio.pg_error;
-	if (err < 0)
+	if (nfs_error_is_fatal(err))
 		goto out_err;
 	return 0;
 out_err:
@@ -782,7 +786,6 @@
 	struct nfs_inode *nfsi = NFS_I(inode);
 	struct nfs_page *head;
 
-	atomic_long_dec(&nfsi->nrequests);
 	if (nfs_page_group_sync_on_bit(req, PG_REMOVE)) {
 		head = req->wb_head;
 
@@ -795,8 +798,10 @@
 		spin_unlock(&mapping->private_lock);
 	}
 
-	if (test_and_clear_bit(PG_INODE_REF, &req->wb_flags))
+	if (test_and_clear_bit(PG_INODE_REF, &req->wb_flags)) {
 		nfs_release_request(req);
+		atomic_long_dec(&nfsi->nrequests);
+	}
 }
 
 static void
@@ -864,7 +869,6 @@
 /**
  * nfs_request_add_commit_list - add request to a commit list
  * @req: pointer to a struct nfs_page
- * @dst: commit list head
  * @cinfo: holds list lock and accounting info
  *
  * This sets the PG_CLEAN bit, updates the cinfo count of
@@ -953,7 +957,8 @@
 nfs_clear_request_commit(struct nfs_page *req)
 {
 	if (test_bit(PG_CLEAN, &req->wb_flags)) {
-		struct inode *inode = d_inode(req->wb_context->dentry);
+		struct nfs_open_context *ctx = nfs_req_openctx(req);
+		struct inode *inode = d_inode(ctx->dentry);
 		struct nfs_commit_info cinfo;
 
 		nfs_init_cinfo_from_inode(&cinfo, inode);
@@ -993,11 +998,13 @@
 		nfs_list_remove_request(req);
 		if (test_bit(NFS_IOHDR_ERROR, &hdr->flags) &&
 		    (hdr->good_bytes < bytes)) {
-			nfs_set_pageerror(req->wb_page);
-			nfs_context_set_write_error(req->wb_context, hdr->error);
+			nfs_set_pageerror(page_file_mapping(req->wb_page));
+			nfs_mapping_set_error(req->wb_page, hdr->error);
 			goto remove_req;
 		}
 		if (nfs_write_need_commit(hdr)) {
+			/* Reset wb_nio, since the write was successful. */
+			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);
@@ -1131,6 +1138,7 @@
 		req->wb_bytes = end - req->wb_offset;
 	else
 		req->wb_bytes = rqend - req->wb_offset;
+	req->wb_nio = 0;
 	return req;
 out_flushme:
 	/*
@@ -1160,7 +1168,7 @@
 	req = nfs_try_to_update_request(inode, page, offset, bytes);
 	if (req != NULL)
 		goto out;
-	req = nfs_create_request(ctx, page, NULL, offset, bytes);
+	req = nfs_create_request(ctx, page, offset, bytes);
 	if (IS_ERR(req))
 		goto out;
 	nfs_inode_add_request(inode, req);
@@ -1205,7 +1213,7 @@
 			return 0;
 		l_ctx = req->wb_lock_context;
 		do_flush = req->wb_page != page ||
-			!nfs_match_open_context(req->wb_context, ctx);
+			!nfs_match_open_context(nfs_req_openctx(req), ctx);
 		if (l_ctx && flctx &&
 		    !(list_empty_careful(&flctx->flc_posix) &&
 		      list_empty_careful(&flctx->flc_flock))) {
@@ -1233,9 +1241,12 @@
 nfs_key_timeout_notify(struct file *filp, struct inode *inode)
 {
 	struct nfs_open_context *ctx = nfs_file_open_context(filp);
-	struct rpc_auth *auth = NFS_SERVER(inode)->client->cl_auth;
 
-	return rpcauth_key_timeout_notify(auth, ctx->cred);
+	if (nfs_ctx_key_to_expire(ctx, inode) &&
+	    !ctx->ll_cred)
+		/* Already expired! */
+		return -EACCES;
+	return 0;
 }
 
 /*
@@ -1244,8 +1255,23 @@
 bool nfs_ctx_key_to_expire(struct nfs_open_context *ctx, struct inode *inode)
 {
 	struct rpc_auth *auth = NFS_SERVER(inode)->client->cl_auth;
+	struct rpc_cred *cred = ctx->ll_cred;
+	struct auth_cred acred = {
+		.cred = ctx->cred,
+	};
 
-	return rpcauth_cred_key_to_expire(auth, ctx->cred);
+	if (cred && !cred->cr_ops->crmatch(&acred, cred, 0)) {
+		put_rpccred(cred);
+		ctx->ll_cred = NULL;
+		cred = NULL;
+	}
+	if (!cred)
+		cred = auth->au_ops->lookup_cred(auth, &acred, 0);
+	if (!cred || IS_ERR(cred))
+		return true;
+	ctx->ll_cred = cred;
+	return !!(cred->cr_ops->crkey_timeout &&
+		  cred->cr_ops->crkey_timeout(cred));
 }
 
 /*
@@ -1329,7 +1355,8 @@
 		unsigned int offset, unsigned int count)
 {
 	struct nfs_open_context *ctx = nfs_file_open_context(file);
-	struct inode	*inode = page_file_mapping(page)->host;
+	struct address_space *mapping = page_file_mapping(page);
+	struct inode	*inode = mapping->host;
 	int		status = 0;
 
 	nfs_inc_stats(inode, NFSIOS_VFSUPDATEPAGE);
@@ -1347,7 +1374,7 @@
 
 	status = nfs_writepage_setup(ctx, page, offset, count);
 	if (status < 0)
-		nfs_set_pageerror(page);
+		nfs_set_pageerror(mapping);
 	else
 		__set_page_dirty_nobuffers(page);
 out:
@@ -1386,26 +1413,31 @@
  */
 static void nfs_redirty_request(struct nfs_page *req)
 {
+	/* Bump the transmission count */
+	req->wb_nio++;
 	nfs_mark_request_dirty(req);
-	set_bit(NFS_CONTEXT_RESEND_WRITES, &req->wb_context->flags);
+	set_bit(NFS_CONTEXT_RESEND_WRITES, &nfs_req_openctx(req)->flags);
 	nfs_end_page_writeback(req);
 	nfs_release_request(req);
 }
 
-static void nfs_async_write_error(struct list_head *head)
+static void nfs_async_write_error(struct list_head *head, int error)
 {
 	struct nfs_page	*req;
 
 	while (!list_empty(head)) {
 		req = nfs_list_entry(head->next);
 		nfs_list_remove_request(req);
-		nfs_redirty_request(req);
+		if (nfs_error_is_fatal(error))
+			nfs_write_error(req, error);
+		else
+			nfs_redirty_request(req);
 	}
 }
 
 static void nfs_async_write_reschedule_io(struct nfs_pgio_header *hdr)
 {
-	nfs_async_write_error(&hdr->pages);
+	nfs_async_write_error(&hdr->pages, 0);
 	filemap_fdatawrite_range(hdr->inode->i_mapping, hdr->args.offset,
 			hdr->args.offset + hdr->args.count - 1);
 }
@@ -1704,7 +1736,8 @@
 		     struct nfs_commit_info *cinfo)
 {
 	struct nfs_page *first = nfs_list_entry(head->next);
-	struct inode *inode = d_inode(first->wb_context->dentry);
+	struct nfs_open_context *ctx = nfs_req_openctx(first);
+	struct inode *inode = d_inode(ctx->dentry);
 
 	/* Set up the RPC argument and reply structs
 	 * NB: take care not to mess about with data->commit et al. */
@@ -1712,7 +1745,7 @@
 	list_splice_init(head, &data->pages);
 
 	data->inode	  = inode;
-	data->cred	  = first->wb_context->cred;
+	data->cred	  = ctx->cred;
 	data->lseg	  = lseg; /* reference transferred */
 	/* only set lwb for pnfs commit */
 	if (lseg)
@@ -1725,7 +1758,7 @@
 	/* Note: we always request a commit of the entire inode */
 	data->args.offset = 0;
 	data->args.count  = 0;
-	data->context     = get_nfs_open_context(first->wb_context);
+	data->context     = get_nfs_open_context(ctx);
 	data->res.fattr   = &data->fattr;
 	data->res.verf    = &data->verf;
 	nfs_fattr_init(&data->fattr);
@@ -1808,14 +1841,15 @@
 			nfs_clear_page_commit(req->wb_page);
 
 		dprintk("NFS:       commit (%s/%llu %d@%lld)",
-			req->wb_context->dentry->d_sb->s_id,
-			(unsigned long long)NFS_FILEID(d_inode(req->wb_context->dentry)),
+			nfs_req_openctx(req)->dentry->d_sb->s_id,
+			(unsigned long long)NFS_FILEID(d_inode(nfs_req_openctx(req)->dentry)),
 			req->wb_bytes,
 			(long long)req_offset(req));
 		if (status < 0) {
-			nfs_context_set_write_error(req->wb_context, status);
-			if (req->wb_page)
+			if (req->wb_page) {
+				nfs_mapping_set_error(req->wb_page, status);
 				nfs_inode_remove_request(req);
+			}
 			dprintk_cont(", error = %d\n", status);
 			goto next;
 		}
@@ -1832,7 +1866,7 @@
 		/* We have a mismatch. Write the page again */
 		dprintk_cont(" mismatch\n");
 		nfs_mark_request_dirty(req);
-		set_bit(NFS_CONTEXT_RESEND_WRITES, &req->wb_context->flags);
+		set_bit(NFS_CONTEXT_RESEND_WRITES, &nfs_req_openctx(req)->flags);
 	next:
 		nfs_unlock_and_release_request(req);
 		/* Latency breaker */
@@ -2121,7 +2155,7 @@
 	 * This allows larger machines to have larger/more transfers.
 	 * Limit the default to 256M
 	 */
-	nfs_congestion_kb = (16*int_sqrt(totalram_pages)) << (PAGE_SHIFT-10);
+	nfs_congestion_kb = (16*int_sqrt(totalram_pages())) << (PAGE_SHIFT-10);
 	if (nfs_congestion_kb > 256*1024)
 		nfs_congestion_kb = 256*1024;