From: Jeff Layton <jlayton@kernel.org>
Date: Thu, 1 Aug 2019 10:06:40 -0400
Subject: ceph: don't freeze during write page faults
Git-commit: 249c1df59a508969f5263ac7e3aedfce7f52c556
Patch-mainline: v5.4-rc1
References: jsc#SES-1134

Prevent freezing operations during write page faults. This is good
practice for most filesystems, but especially for ceph since we're
monkeying with the signal table here.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Acked-by: Luis Henriques <lhenriques@suse.com>
---
 fs/ceph/addr.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c
index 90e8f8487aaf..9efd51926792 100644
--- a/fs/ceph/addr.c
+++ b/fs/ceph/addr.c
@@ -1548,6 +1548,7 @@ static vm_fault_t ceph_page_mkwrite(struct vm_fault *vmf)
 	if (!prealloc_cf)
 		return VM_FAULT_OOM;
 
+	sb_start_pagefault(inode->i_sb);
 	ceph_block_sigs(&oldset);
 
 	if (ci->i_inline_version != CEPH_INLINE_NONE) {
@@ -1622,6 +1623,7 @@ static vm_fault_t ceph_page_mkwrite(struct vm_fault *vmf)
 	ceph_put_cap_refs(ci, got);
 out_free:
 	ceph_restore_sigs(&oldset);
+	sb_end_pagefault(inode->i_sb);
 	ceph_free_cap_flush(prealloc_cf);
 	if (err < 0)
 		ret = vmf_error(err);