libceph: don't consume a ref on pagelist in ceph_msg_data_add_pagelist()

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>
This commit is contained in:
Ilya Dryomov 2018-09-28 16:02:53 +02:00
Родитель 33165d4723
Коммит 894868330a
3 изменённых файлов: 10 добавлений и 1 удалений

Просмотреть файл

@ -2136,7 +2136,6 @@ static struct ceph_msg *create_request_message(struct ceph_mds_client *mdsc,
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 {
@ -3240,6 +3239,7 @@ static void send_mds_reconnect(struct ceph_mds_client *mdsc,
mutex_unlock(&mdsc->mutex);
up_read(&mdsc->snap_rwsem);
ceph_pagelist_release(pagelist);
return;
fail:

Просмотреть файл

@ -3313,6 +3313,7 @@ void ceph_msg_data_add_pagelist(struct ceph_msg *msg,
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);

Просмотреть файл

@ -126,6 +126,9 @@ static void ceph_osd_data_init(struct ceph_osd_data *osd_data)
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)
@ -138,6 +141,9 @@ static void ceph_osd_data_pages_init(struct ceph_osd_data *osd_data,
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)
{
@ -362,6 +368,8 @@ static void ceph_osd_data_release(struct ceph_osd_data *osd_data)
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);
}