In place of the message data pointer, use a list head which links
through message data items. For now we only support a single entry
on that list.
Signed-off-by: Alex Elder <elder@xxxxxxxxxxx>
---
include/linux/ceph/messenger.h | 3 ++-
net/ceph/messenger.c | 46
+++++++++++++++++++++++++++-------------
2 files changed, 33 insertions(+), 16 deletions(-)
diff --git a/include/linux/ceph/messenger.h b/include/linux/ceph/messenger.h
index 8846ff6..318da01 100644
--- a/include/linux/ceph/messenger.h
+++ b/include/linux/ceph/messenger.h
@@ -89,6 +89,7 @@ static __inline__ bool ceph_msg_data_type_valid(enum
ceph_msg_data_type type)
}
struct ceph_msg_data {
+ struct list_head links; /* ceph_msg->data */
enum ceph_msg_data_type type;
union {
#ifdef CONFIG_BLOCK
@@ -143,7 +144,7 @@ struct ceph_msg {
struct ceph_buffer *middle;
size_t data_length;
- struct ceph_msg_data *data;
+ struct list_head data;
struct ceph_msg_data_cursor cursor;
struct ceph_connection *con;
diff --git a/net/ceph/messenger.c b/net/ceph/messenger.c
index 50b4093..9ce667e 100644
--- a/net/ceph/messenger.c
+++ b/net/ceph/messenger.c
@@ -985,8 +985,10 @@ static bool ceph_msg_data_pagelist_advance(struct
ceph_msg_data_cursor *cursor,
static void ceph_msg_data_cursor_init(struct ceph_msg *msg, size_t length)
{
struct ceph_msg_data_cursor *cursor = &msg->cursor;
+ struct ceph_msg_data *data;
- cursor->data = msg->data;
+ data = list_first_entry(&msg->data, struct ceph_msg_data, links);
+ cursor->data = data;
switch (cursor->data->type) {
case CEPH_MSG_DATA_PAGELIST:
ceph_msg_data_pagelist_cursor_init(cursor, length);
@@ -1410,7 +1412,7 @@ static int write_partial_message_data(struct
ceph_connection *con)
dout("%s %p msg %p\n", __func__, con, msg);
- if (WARN_ON(!msg->data))
+ if (list_empty(&msg->data))
return -EINVAL;
/*
@@ -2111,7 +2113,7 @@ static int read_partial_msg_data(struct
ceph_connection *con)
int ret;
BUG_ON(!msg);
- if (!msg->data)
+ if (list_empty(&msg->data))
return -EIO;
if (do_datacrc)
@@ -2961,6 +2963,7 @@ static struct ceph_msg_data
*ceph_msg_data_create(enum ceph_msg_data_type type)
data = kzalloc(sizeof (*data), GFP_NOFS);
if (data)
data->type = type;
+ INIT_LIST_HEAD(&data->links);
return data;
}
@@ -2970,6 +2973,7 @@ static void ceph_msg_data_destroy(struct
ceph_msg_data *data)
if (!data)
return;
+ WARN_ON(!list_empty(&data->links));
if (data->type == CEPH_MSG_DATA_PAGELIST) {
ceph_pagelist_release(data->pagelist);
kfree(data->pagelist);
@@ -2985,7 +2989,7 @@ void ceph_msg_data_set_pages(struct ceph_msg *msg,
struct page **pages,
BUG_ON(!pages);
BUG_ON(!length);
BUG_ON(msg->data_length);
- BUG_ON(msg->data != NULL);
+ BUG_ON(!list_empty(&msg->data));
data = ceph_msg_data_create(CEPH_MSG_DATA_PAGES);
BUG_ON(!data);
@@ -2993,8 +2997,9 @@ void ceph_msg_data_set_pages(struct ceph_msg *msg,
struct page **pages,
data->length = length;
data->alignment = alignment & ~PAGE_MASK;
- msg->data = data;
- msg->data_length = length;
+ BUG_ON(!list_empty(&msg->data));
+ list_add_tail(&data->links, &msg->data);
+ msg->data_length += length;
}
EXPORT_SYMBOL(ceph_msg_data_set_pages);
@@ -3006,14 +3011,14 @@ void ceph_msg_data_set_pagelist(struct ceph_msg
*msg,
BUG_ON(!pagelist);
BUG_ON(!pagelist->length);
BUG_ON(msg->data_length);
- BUG_ON(msg->data != NULL);
+ BUG_ON(!list_empty(&msg->data));
data = ceph_msg_data_create(CEPH_MSG_DATA_PAGELIST);
BUG_ON(!data);
data->pagelist = pagelist;
- msg->data = data;
- msg->data_length = pagelist->length;
+ list_add_tail(&data->links, &msg->data);
+ msg->data_length += pagelist->length;
}
EXPORT_SYMBOL(ceph_msg_data_set_pagelist);
@@ -3025,15 +3030,15 @@ void ceph_msg_data_set_bio(struct ceph_msg *msg,
struct bio *bio,
BUG_ON(!bio);
BUG_ON(msg->data_length);
- BUG_ON(msg->data != NULL);
+ BUG_ON(!list_empty(&msg->data));
data = ceph_msg_data_create(CEPH_MSG_DATA_BIO);
BUG_ON(!data);
data->bio = bio;
data->bio_length = length;
- msg->data = data;
- msg->data_length = length;
+ list_add_tail(&data->links, &msg->data);
+ msg->data_length += length;
}
EXPORT_SYMBOL(ceph_msg_data_set_bio);
#endif /* CONFIG_BLOCK */
@@ -3057,6 +3062,7 @@ struct ceph_msg *ceph_msg_new(int type, int
front_len, gfp_t flags,
INIT_LIST_HEAD(&m->list_head);
kref_init(&m->kref);
+ INIT_LIST_HEAD(&m->data);
/* front */
m->front_max = front_len;
@@ -3202,6 +3208,9 @@ void ceph_msg_kfree(struct ceph_msg *m)
void ceph_msg_last_put(struct kref *kref)
{
struct ceph_msg *m = container_of(kref, struct ceph_msg, kref);
+ LIST_HEAD(data);
+ struct list_head *links;
+ struct list_head *next;
dout("ceph_msg_put last one on %p\n", m);
WARN_ON(!list_empty(&m->list_head));
@@ -3211,8 +3220,15 @@ void ceph_msg_last_put(struct kref *kref)
ceph_buffer_put(m->middle);
m->middle = NULL;
}
- ceph_msg_data_destroy(m->data);
- m->data = NULL;
+
+ list_splice_init(&m->data, &data);
+ list_for_each_safe(links, next, &data) {
+ struct ceph_msg_data *data;
+
+ data = list_entry(links, struct ceph_msg_data, links);
+ list_del_init(links);
+ ceph_msg_data_destroy(data);
+ }
m->data_length = 0;
if (m->pool)
@@ -3225,7 +3241,7 @@ EXPORT_SYMBOL(ceph_msg_last_put);
void ceph_msg_dump(struct ceph_msg *msg)
{
pr_debug("msg_dump %p (front_max %d length %zd)\n", msg,
- msg->front_max, msg->data->length);
+ msg->front_max, msg->data_length);
print_hex_dump(KERN_DEBUG, "header: ",
DUMP_PREFIX_OFFSET, 16, 1,
&msg->hdr, sizeof(msg->hdr), true);
