From: Ilya Dryomov <idryomov@gmail.com>
Date: Fri, 28 Sep 2018 16:02:53 +0200
Subject: libceph: don't consume a ref on pagelist in
ceph_msg_data_add_pagelist()
Git-commit: 894868330a1e038ea4a65dbb81741eef70ad71b1
Patch-mainline: v4.20-rc1
References: bsc#1135897
Because send_mds_reconnect() wants to send a message with a pagelist
and pass the ownership to the messenger, ceph_msg_data_add_pagelist()
consumes a ref which is then put in ceph_msg_data_destroy(). This
makes managing pagelists in the OSD client (where they are wrapped in
ceph_osd_data) unnecessarily hard because the handoff only happens in
ceph_osdc_start_request() instead of when the pagelist is passed to
ceph_osd_data_pagelist_init(). I counted several memory leaks on
various error paths.
Fix up ceph_msg_data_add_pagelist() and carry a pagelist ref in
ceph_osd_data.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Acked-by: Luis Henriques <lhenriques@suse.com>
---
fs/ceph/mds_client.c | 2 +-
net/ceph/messenger.c | 1 +
net/ceph/osd_client.c | 8 ++++++++
3 files changed, 10 insertions(+), 1 deletion(-)
--- a/fs/ceph/mds_client.c
+++ b/fs/ceph/mds_client.c
@@ -2133,7 +2133,6 @@ static struct ceph_msg *create_request_m
if (req->r_pagelist) {
struct ceph_pagelist *pagelist = req->r_pagelist;
- refcount_inc(&pagelist->refcnt);
ceph_msg_data_add_pagelist(msg, pagelist);
msg->hdr.data_len = cpu_to_le32(pagelist->length);
} else {
@@ -3236,6 +3235,7 @@ static void send_mds_reconnect(struct ce
mutex_unlock(&mdsc->mutex);
up_read(&mdsc->snap_rwsem);
+ ceph_pagelist_release(pagelist);
return;
fail:
--- a/net/ceph/messenger.c
+++ b/net/ceph/messenger.c
@@ -3312,6 +3312,7 @@ void ceph_msg_data_add_pagelist(struct c
data = ceph_msg_data_create(CEPH_MSG_DATA_PAGELIST);
BUG_ON(!data);
+ refcount_inc(&pagelist->refcnt);
data->pagelist = pagelist;
list_add_tail(&data->links, &msg->data);
--- a/net/ceph/osd_client.c
+++ b/net/ceph/osd_client.c
@@ -124,6 +124,9 @@ static void ceph_osd_data_init(struct ce
osd_data->type = CEPH_OSD_DATA_TYPE_NONE;
}
+/*
+ * Consumes @pages if @own_pages is true.
+ */
static void ceph_osd_data_pages_init(struct ceph_osd_data *osd_data,
struct page **pages, u64 length, u32 alignment,
bool pages_from_pool, bool own_pages)
@@ -136,6 +139,9 @@ static void ceph_osd_data_pages_init(str
osd_data->own_pages = own_pages;
}
+/*
+ * Consumes a ref on @pagelist.
+ */
static void ceph_osd_data_pagelist_init(struct ceph_osd_data *osd_data,
struct ceph_pagelist *pagelist)
{
@@ -360,6 +366,8 @@ static void ceph_osd_data_release(struct
num_pages = calc_pages_for((u64)osd_data->alignment,
(u64)osd_data->length);
ceph_release_page_vector(osd_data->pages, num_pages);
+ } else if (osd_data->type == CEPH_OSD_DATA_TYPE_PAGELIST) {
+ ceph_pagelist_release(osd_data->pagelist);
}
ceph_osd_data_init(osd_data);
}