ceph: messenger and osdc changes for rbd
Allow the messenger to send/receive data in a bio. This is added
so that we wouldn't need to copy the data into pages or some other buffer
when doing IO for an rbd block device.
We can now have trailing variable sized data for osd
ops. Also osd ops encoding is more modular.
Signed-off-by: Yehuda Sadeh <yehuda@hq.newdream.net>
Signed-off-by: Sage Weil <sage@newdream.net>
diff --git a/fs/ceph/messenger.c b/fs/ceph/messenger.c
index 2502d76..17a09b3 100644
--- a/fs/ceph/messenger.c
+++ b/fs/ceph/messenger.c
@@ -9,6 +9,8 @@
#include <linux/slab.h>
#include <linux/socket.h>
#include <linux/string.h>
+#include <linux/bio.h>
+#include <linux/blkdev.h>
#include <net/tcp.h>
#include "super.h"
@@ -529,8 +531,11 @@
if (le32_to_cpu(m->hdr.data_len) > 0) {
/* initialize page iterator */
con->out_msg_pos.page = 0;
- con->out_msg_pos.page_pos =
- le16_to_cpu(m->hdr.data_off) & ~PAGE_MASK;
+ if (m->pages)
+ con->out_msg_pos.page_pos =
+ le16_to_cpu(m->hdr.data_off) & ~PAGE_MASK;
+ else
+ con->out_msg_pos.page_pos = 0;
con->out_msg_pos.data_pos = 0;
con->out_msg_pos.did_page_crc = 0;
con->out_more = 1; /* data + footer will follow */
@@ -712,6 +717,31 @@
return ret; /* done! */
}
+#ifdef CONFIG_BLOCK
+static void init_bio_iter(struct bio *bio, struct bio **iter, int *seg)
+{
+ if (!bio) {
+ *iter = NULL;
+ *seg = 0;
+ return;
+ }
+ *iter = bio;
+ *seg = bio->bi_idx;
+}
+
+static void iter_bio_next(struct bio **bio_iter, int *seg)
+{
+ if (*bio_iter == NULL)
+ return;
+
+ BUG_ON(*seg >= (*bio_iter)->bi_vcnt);
+
+ (*seg)++;
+ if (*seg == (*bio_iter)->bi_vcnt)
+ init_bio_iter((*bio_iter)->bi_next, bio_iter, seg);
+}
+#endif
+
/*
* Write as much message data payload as we can. If we finish, queue
* up the footer.
@@ -726,21 +756,46 @@
size_t len;
int crc = con->msgr->nocrc;
int ret;
+ int total_max_write;
+ int in_trail = 0;
+ size_t trail_len = (msg->trail ? msg->trail->length : 0);
dout("write_partial_msg_pages %p msg %p page %d/%d offset %d\n",
con, con->out_msg, con->out_msg_pos.page, con->out_msg->nr_pages,
con->out_msg_pos.page_pos);
- while (con->out_msg_pos.page < con->out_msg->nr_pages) {
+#ifdef CONFIG_BLOCK
+ if (msg->bio && !msg->bio_iter)
+ init_bio_iter(msg->bio, &msg->bio_iter, &msg->bio_seg);
+#endif
+
+ while (data_len > con->out_msg_pos.data_pos) {
struct page *page = NULL;
void *kaddr = NULL;
+ int max_write = PAGE_SIZE;
+ int page_shift = 0;
+
+ total_max_write = data_len - trail_len -
+ con->out_msg_pos.data_pos;
/*
* if we are calculating the data crc (the default), we need
* to map the page. if our pages[] has been revoked, use the
* zero page.
*/
- if (msg->pages) {
+
+ /* have we reached the trail part of the data? */
+ if (con->out_msg_pos.data_pos >= data_len - trail_len) {
+ in_trail = 1;
+
+ total_max_write = data_len - con->out_msg_pos.data_pos;
+
+ page = list_first_entry(&msg->trail->head,
+ struct page, lru);
+ if (crc)
+ kaddr = kmap(page);
+ max_write = PAGE_SIZE;
+ } else if (msg->pages) {
page = msg->pages[con->out_msg_pos.page];
if (crc)
kaddr = kmap(page);
@@ -749,13 +804,25 @@
struct page, lru);
if (crc)
kaddr = kmap(page);
+#ifdef CONFIG_BLOCK
+ } else if (msg->bio) {
+ struct bio_vec *bv;
+
+ bv = bio_iovec_idx(msg->bio_iter, msg->bio_seg);
+ page = bv->bv_page;
+ page_shift = bv->bv_offset;
+ if (crc)
+ kaddr = kmap(page) + page_shift;
+ max_write = bv->bv_len;
+#endif
} else {
page = con->msgr->zero_page;
if (crc)
kaddr = page_address(con->msgr->zero_page);
}
- len = min((int)(PAGE_SIZE - con->out_msg_pos.page_pos),
- (int)(data_len - con->out_msg_pos.data_pos));
+ len = min_t(int, max_write - con->out_msg_pos.page_pos,
+ total_max_write);
+
if (crc && !con->out_msg_pos.did_page_crc) {
void *base = kaddr + con->out_msg_pos.page_pos;
u32 tmpcrc = le32_to_cpu(con->out_msg->footer.data_crc);
@@ -765,13 +832,14 @@
cpu_to_le32(crc32c(tmpcrc, base, len));
con->out_msg_pos.did_page_crc = 1;
}
-
ret = kernel_sendpage(con->sock, page,
- con->out_msg_pos.page_pos, len,
+ con->out_msg_pos.page_pos + page_shift,
+ len,
MSG_DONTWAIT | MSG_NOSIGNAL |
MSG_MORE);
- if (crc && (msg->pages || msg->pagelist))
+ if (crc &&
+ (msg->pages || msg->pagelist || msg->bio || in_trail))
kunmap(page);
if (ret <= 0)
@@ -783,9 +851,16 @@
con->out_msg_pos.page_pos = 0;
con->out_msg_pos.page++;
con->out_msg_pos.did_page_crc = 0;
- if (msg->pagelist)
+ if (in_trail)
+ list_move_tail(&page->lru,
+ &msg->trail->head);
+ else if (msg->pagelist)
list_move_tail(&page->lru,
&msg->pagelist->head);
+#ifdef CONFIG_BLOCK
+ else if (msg->bio)
+ iter_bio_next(&msg->bio_iter, &msg->bio_seg);
+#endif
}
}
@@ -1305,8 +1380,7 @@
struct kvec *section,
unsigned int sec_len, u32 *crc)
{
- int left;
- int ret;
+ int ret, left;
BUG_ON(!section);
@@ -1329,13 +1403,83 @@
static struct ceph_msg *ceph_alloc_msg(struct ceph_connection *con,
struct ceph_msg_header *hdr,
int *skip);
+
+
+static int read_partial_message_pages(struct ceph_connection *con,
+ struct page **pages,
+ unsigned data_len, int datacrc)
+{
+ void *p;
+ int ret;
+ int left;
+
+ left = min((int)(data_len - con->in_msg_pos.data_pos),
+ (int)(PAGE_SIZE - con->in_msg_pos.page_pos));
+ /* (page) data */
+ BUG_ON(pages == NULL);
+ p = kmap(pages[con->in_msg_pos.page]);
+ ret = ceph_tcp_recvmsg(con->sock, p + con->in_msg_pos.page_pos,
+ left);
+ if (ret > 0 && datacrc)
+ con->in_data_crc =
+ crc32c(con->in_data_crc,
+ p + con->in_msg_pos.page_pos, ret);
+ kunmap(pages[con->in_msg_pos.page]);
+ if (ret <= 0)
+ return ret;
+ con->in_msg_pos.data_pos += ret;
+ con->in_msg_pos.page_pos += ret;
+ if (con->in_msg_pos.page_pos == PAGE_SIZE) {
+ con->in_msg_pos.page_pos = 0;
+ con->in_msg_pos.page++;
+ }
+
+ return ret;
+}
+
+#ifdef CONFIG_BLOCK
+static int read_partial_message_bio(struct ceph_connection *con,
+ struct bio **bio_iter, int *bio_seg,
+ unsigned data_len, int datacrc)
+{
+ struct bio_vec *bv = bio_iovec_idx(*bio_iter, *bio_seg);
+ void *p;
+ int ret, left;
+
+ if (IS_ERR(bv))
+ return PTR_ERR(bv);
+
+ left = min((int)(data_len - con->in_msg_pos.data_pos),
+ (int)(bv->bv_len - con->in_msg_pos.page_pos));
+
+ p = kmap(bv->bv_page) + bv->bv_offset;
+
+ ret = ceph_tcp_recvmsg(con->sock, p + con->in_msg_pos.page_pos,
+ left);
+ if (ret > 0 && datacrc)
+ con->in_data_crc =
+ crc32c(con->in_data_crc,
+ p + con->in_msg_pos.page_pos, ret);
+ kunmap(bv->bv_page);
+ if (ret <= 0)
+ return ret;
+ con->in_msg_pos.data_pos += ret;
+ con->in_msg_pos.page_pos += ret;
+ if (con->in_msg_pos.page_pos == bv->bv_len) {
+ con->in_msg_pos.page_pos = 0;
+ iter_bio_next(bio_iter, bio_seg);
+ }
+
+ return ret;
+}
+#endif
+
/*
* read (part of) a message.
*/
static int read_partial_message(struct ceph_connection *con)
{
struct ceph_msg *m = con->in_msg;
- void *p;
int ret;
int to, left;
unsigned front_len, middle_len, data_len, data_off;
@@ -1422,7 +1566,10 @@
m->middle->vec.iov_len = 0;
con->in_msg_pos.page = 0;
- con->in_msg_pos.page_pos = data_off & ~PAGE_MASK;
+ if (m->pages)
+ con->in_msg_pos.page_pos = data_off & ~PAGE_MASK;
+ else
+ con->in_msg_pos.page_pos = 0;
con->in_msg_pos.data_pos = 0;
}
@@ -1440,27 +1587,29 @@
if (ret <= 0)
return ret;
}
+#ifdef CONFIG_BLOCK
+ if (m->bio && !m->bio_iter)
+ init_bio_iter(m->bio, &m->bio_iter, &m->bio_seg);
+#endif
/* (page) data */
while (con->in_msg_pos.data_pos < data_len) {
- left = min((int)(data_len - con->in_msg_pos.data_pos),
- (int)(PAGE_SIZE - con->in_msg_pos.page_pos));
- BUG_ON(m->pages == NULL);
- p = kmap(m->pages[con->in_msg_pos.page]);
- ret = ceph_tcp_recvmsg(con->sock, p + con->in_msg_pos.page_pos,
- left);
- if (ret > 0 && datacrc)
- con->in_data_crc =
- crc32c(con->in_data_crc,
- p + con->in_msg_pos.page_pos, ret);
- kunmap(m->pages[con->in_msg_pos.page]);
- if (ret <= 0)
- return ret;
- con->in_msg_pos.data_pos += ret;
- con->in_msg_pos.page_pos += ret;
- if (con->in_msg_pos.page_pos == PAGE_SIZE) {
- con->in_msg_pos.page_pos = 0;
- con->in_msg_pos.page++;
+ if (m->pages) {
+ ret = read_partial_message_pages(con, m->pages,
+ data_len, datacrc);
+ if (ret <= 0)
+ return ret;
+#ifdef CONFIG_BLOCK
+ } else if (m->bio) {
+
+ ret = read_partial_message_bio(con,
+ &m->bio_iter, &m->bio_seg,
+ data_len, datacrc);
+ if (ret <= 0)
+ return ret;
+#endif
+ } else {
+ BUG_ON(1);
}
}
@@ -2136,6 +2285,10 @@
m->nr_pages = 0;
m->pages = NULL;
m->pagelist = NULL;
+ m->bio = NULL;
+ m->bio_iter = NULL;
+ m->bio_seg = 0;
+ m->trail = NULL;
dout("ceph_msg_new %p front %d\n", m, front_len);
return m;
@@ -2250,6 +2403,8 @@
m->pagelist = NULL;
}
+ m->trail = NULL;
+
if (m->pool)
ceph_msgpool_put(m->pool, m);
else