libceph: define and use ceph_tcp_recvpage()

Define a new function ceph_tcp_recvpage() that behaves in a way
comparable to ceph_tcp_sendpage().

Rearrange the code in both read_partial_message_pages() and
read_partial_message_bio() so they have matching structure,
(similar to what's in write_partial_msg_pages()), and use
this new function.

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 20:58:59 -06:00 committed by Sage Weil
parent 34d2d2006c
commit afb3d90e20
1 changed files with 60 additions and 26 deletions

View File

@ -471,6 +471,22 @@ static int ceph_tcp_recvmsg(struct socket *sock, void *buf, size_t len)
return r;
}
static int ceph_tcp_recvpage(struct socket *sock, struct page *page,
int page_offset, size_t length)
{
void *kaddr;
int ret;
BUG_ON(page_offset + length > PAGE_SIZE);
kaddr = kmap(page);
BUG_ON(!kaddr);
ret = ceph_tcp_recvmsg(sock, kaddr + page_offset, length);
kunmap(page);
return ret;
}
/*
* write something. @more is true if caller will be sending more data
* shortly.
@ -1809,26 +1825,36 @@ static int read_partial_message_pages(struct ceph_connection *con,
{
struct ceph_msg_pos *msg_pos = &con->in_msg_pos;
struct page *page;
void *p;
size_t page_offset;
size_t length;
unsigned int left;
int ret;
int left;
left = min((int)(data_len - msg_pos->data_pos),
(int)(PAGE_SIZE - msg_pos->page_pos));
/* (page) data */
BUG_ON(pages == NULL);
page = pages[msg_pos->page];
p = kmap(page);
ret = ceph_tcp_recvmsg(con->sock, p + msg_pos->page_pos, left);
if (ret > 0 && do_datacrc)
con->in_data_crc =
crc32c(con->in_data_crc,
p + msg_pos->page_pos, ret);
kunmap(page);
page_offset = msg_pos->page_pos;
BUG_ON(msg_pos->data_pos >= data_len);
left = data_len - msg_pos->data_pos;
BUG_ON(page_offset >= PAGE_SIZE);
length = min_t(unsigned int, PAGE_SIZE - page_offset, left);
ret = ceph_tcp_recvpage(con->sock, page, page_offset, length);
if (ret <= 0)
return ret;
in_msg_pos_next(con, left, ret);
if (do_datacrc) {
void *kaddr;
void *base;
kaddr = kmap(page);
BUG_ON(!kaddr);
base = kaddr + page_offset;
con->in_data_crc = crc32c(con->in_data_crc, base, ret);
kunmap(page);
}
in_msg_pos_next(con, length, ret);
return ret;
}
@ -1841,29 +1867,37 @@ static int read_partial_message_bio(struct ceph_connection *con,
struct ceph_msg_pos *msg_pos = &con->in_msg_pos;
struct bio_vec *bv;
struct page *page;
void *p;
int ret, left;
size_t page_offset;
size_t length;
unsigned int left;
int ret;
BUG_ON(!msg);
BUG_ON(!msg->bio_iter);
bv = bio_iovec_idx(msg->bio_iter, msg->bio_seg);
left = min((int)(data_len - msg_pos->data_pos),
(int)(bv->bv_len - msg_pos->page_pos));
page = bv->bv_page;
p = kmap(page) + bv->bv_offset;
page_offset = bv->bv_offset + msg_pos->page_pos;
BUG_ON(msg_pos->data_pos >= data_len);
left = data_len - msg_pos->data_pos;
BUG_ON(msg_pos->page_pos >= bv->bv_len);
length = min_t(unsigned int, bv->bv_len - msg_pos->page_pos, left);
ret = ceph_tcp_recvmsg(con->sock, p + msg_pos->page_pos, left);
if (ret > 0 && do_datacrc)
con->in_data_crc =
crc32c(con->in_data_crc,
p + msg_pos->page_pos, ret);
kunmap(page);
ret = ceph_tcp_recvpage(con->sock, page, page_offset, length);
if (ret <= 0)
return ret;
in_msg_pos_next(con, left, ret);
if (do_datacrc) {
void *kaddr;
void *base;
kaddr = kmap(page);
BUG_ON(!kaddr);
base = kaddr + page_offset;
con->in_data_crc = crc32c(con->in_data_crc, base, ret);
kunmap(page);
}
in_msg_pos_next(con, length, ret);
return ret;
}