libceph: more cleanup of write_partial_msg_pages()

Basically all cases in write_partial_msg_pages() use the cursor, and
as a result we can simplify that function quite a bit.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
This commit is contained in:
Alex Elder 2013-03-08 13:35:36 -06:00 committed by Sage Weil
parent 9d2a06c275
commit 8a166d0536

View File

@ -1476,7 +1476,6 @@ static int write_partial_message_data(struct ceph_connection *con)
unsigned int data_len = le32_to_cpu(msg->hdr.data_len);
bool do_datacrc = !con->msgr->nocrc;
int ret;
int total_max_write;
dout("%s %p msg %p page %d offset %d\n", __func__,
con, msg, msg_pos->page, msg_pos->page_pos);
@ -1490,36 +1489,30 @@ static int write_partial_message_data(struct ceph_connection *con)
* been revoked, so use the zero page.
*/
while (data_len > msg_pos->data_pos) {
struct page *page = NULL;
struct page *page;
size_t page_offset;
size_t length;
bool use_cursor = false;
bool last_piece = true; /* preserve existing behavior */
total_max_write = data_len - msg_pos->data_pos;
bool last_piece;
if (ceph_msg_has_pages(msg)) {
use_cursor = true;
page = ceph_msg_data_next(&msg->p, &page_offset,
&length, &last_piece);
} else if (ceph_msg_has_pagelist(msg)) {
use_cursor = true;
page = ceph_msg_data_next(&msg->l, &page_offset,
&length, &last_piece);
#ifdef CONFIG_BLOCK
} else if (ceph_msg_has_bio(msg)) {
use_cursor = true;
page = ceph_msg_data_next(&msg->b, &page_offset,
&length, &last_piece);
#endif
} else {
page = zero_page;
}
if (!use_cursor) {
length = min_t(int, PAGE_SIZE - msg_pos->page_pos,
total_max_write);
size_t resid = data_len - msg_pos->data_pos;
page = zero_page;
page_offset = msg_pos->page_pos;
length = PAGE_SIZE - page_offset;
length = min(resid, length);
last_piece = length == resid;
}
if (do_datacrc && !msg_pos->did_page_crc) {
u32 crc = le32_to_cpu(msg->footer.data_crc);