9p: use the rcall structure passed in the request in trans_fd read_work
This patch reworks the read_work function to enable it to directly use a passed
in rcall structure. This should help allow us to remove unnecessary copies
in the future.
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
diff --git a/net/9p/trans_fd.c b/net/9p/trans_fd.c
index cc9bc73..627e3f0 100644
--- a/net/9p/trans_fd.c
+++ b/net/9p/trans_fd.c
@@ -111,7 +111,9 @@
* @err: error state
* @req_list: accounting for requests which have been sent
* @unsent_req_list: accounting for requests that haven't been sent
- * @rcall: current response &p9_fcall structure
+ * @req: current request being processed (if any)
+ * @tmp_buf: temporary buffer to read in header
+ * @rsize: amount to read for current frame
* @rpos: read position in current frame
* @rbuf: current read buffer
* @wpos: write position for current frame
@@ -132,7 +134,9 @@
int err;
struct list_head req_list;
struct list_head unsent_req_list;
- struct p9_fcall *rcall;
+ struct p9_req_t *req;
+ char tmp_buf[7];
+ int rsize;
int rpos;
char *rbuf;
int wpos;
@@ -346,34 +350,25 @@
{
int n, err;
struct p9_conn *m;
- struct p9_req_t *req;
- struct p9_fcall *rcall;
- char *rbuf;
m = container_of(work, struct p9_conn, rq);
if (m->err < 0)
return;
- rcall = NULL;
P9_DPRINTK(P9_DEBUG_MUX, "start mux %p pos %d\n", m, m->rpos);
- if (!m->rcall) {
- m->rcall =
- kmalloc(sizeof(struct p9_fcall) + m->client->msize,
- GFP_KERNEL);
- if (!m->rcall) {
- err = -ENOMEM;
- goto error;
- }
-
- m->rbuf = (char *)m->rcall + sizeof(struct p9_fcall);
+ if (!m->rbuf) {
+ m->rbuf = m->tmp_buf;
m->rpos = 0;
+ m->rsize = 7; /* start by reading header */
}
clear_bit(Rpending, &m->wsched);
+ P9_DPRINTK(P9_DEBUG_MUX, "read mux %p pos %d size: %d = %d\n", m,
+ m->rpos, m->rsize, m->rsize-m->rpos);
err = p9_fd_read(m->client, m->rbuf + m->rpos,
- m->client->msize - m->rpos);
+ m->rsize - m->rpos);
P9_DPRINTK(P9_DEBUG_MUX, "mux %p got %d bytes\n", m, err);
if (err == -EAGAIN) {
clear_bit(Rworksched, &m->wsched);
@@ -384,8 +379,12 @@
goto error;
m->rpos += err;
- while (m->rpos > 4) {
- n = le32_to_cpu(*(__le32 *) m->rbuf);
+
+ if ((!m->req) && (m->rpos == m->rsize)) { /* header read in */
+ u16 tag;
+ P9_DPRINTK(P9_DEBUG_MUX, "got new header\n");
+
+ n = le32_to_cpu(*(__le32 *) m->rbuf); /* read packet size */
if (n >= m->client->msize) {
P9_DPRINTK(P9_DEBUG_ERROR,
"requested packet size too big: %d\n", n);
@@ -393,66 +392,71 @@
goto error;
}
- if (m->rpos < n)
- break;
+ tag = le16_to_cpu(*(__le16 *) (m->rbuf+5)); /* read tag */
+ P9_DPRINTK(P9_DEBUG_MUX, "mux %p pkt: size: %d bytes tag: %d\n",
+ m, n, tag);
- err =
- p9_deserialize_fcall(m->rbuf, n, m->rcall, m->client->dotu);
- if (err < 0)
+ m->req = p9_tag_lookup(m->client, tag);
+ if (!m->req) {
+ P9_DPRINTK(P9_DEBUG_ERROR, "Unexpected packet tag %d\n",
+ tag);
+ err = -EIO;
goto error;
+ }
+
+ if (m->req->rc == NULL) {
+ m->req->rc = kmalloc(sizeof(struct p9_fcall) +
+ m->client->msize, GFP_KERNEL);
+ if (!m->req->rc) {
+ m->req = NULL;
+ err = -ENOMEM;
+ goto error;
+ }
+ }
+ m->rbuf = (char *)m->req->rc + sizeof(struct p9_fcall);
+ memcpy(m->rbuf, m->tmp_buf, m->rsize);
+ m->rsize = n;
+ }
+
+ /* not an else because some packets (like clunk) have no payload */
+ if ((m->req) && (m->rpos == m->rsize)) { /* packet is read in */
+ P9_DPRINTK(P9_DEBUG_MUX, "got new packet\n");
+ m->rbuf = (char *)m->req->rc + sizeof(struct p9_fcall);
+ err = p9_deserialize_fcall(m->rbuf, m->rsize, m->req->rc,
+ m->client->dotu);
+ if (err < 0) {
+ m->req = NULL;
+ goto error;
+ }
#ifdef CONFIG_NET_9P_DEBUG
if ((p9_debug_level&P9_DEBUG_FCALL) == P9_DEBUG_FCALL) {
char buf[150];
- p9_printfcall(buf, sizeof(buf), m->rcall,
+ p9_printfcall(buf, sizeof(buf), m->req->rc,
m->client->dotu);
printk(KERN_NOTICE ">>> %p %s\n", m, buf);
}
#endif
- rcall = m->rcall;
- rbuf = m->rbuf;
- if (m->rpos > n) {
- m->rcall = kmalloc(sizeof(struct p9_fcall) +
- m->client->msize, GFP_KERNEL);
- if (!m->rcall) {
- err = -ENOMEM;
- goto error;
- }
-
- m->rbuf = (char *)m->rcall + sizeof(struct p9_fcall);
- memmove(m->rbuf, rbuf + n, m->rpos - n);
- m->rpos -= n;
- } else {
- m->rcall = NULL;
- m->rbuf = NULL;
- m->rpos = 0;
- }
-
P9_DPRINTK(P9_DEBUG_MUX, "mux %p fcall id %d tag %d\n", m,
- rcall->id, rcall->tag);
+ m->req->rc->id, m->req->rc->tag);
- req = p9_tag_lookup(m->client, rcall->tag);
+ m->rbuf = NULL;
+ m->rpos = 0;
+ m->rsize = 0;
- if (req) {
- if (req->status != REQ_STATUS_FLSH) {
- list_del(&req->req_list);
- req->status = REQ_STATUS_RCVD;
- }
-
- req->rc = rcall;
- process_request(m, req);
-
- if (req->status != REQ_STATUS_FLSH)
- p9_conn_rpc_cb(m->client, req);
- } else {
- if (err >= 0 && rcall->id != P9_RFLUSH)
- P9_DPRINTK(P9_DEBUG_ERROR,
- "unexpected response mux %p id %d tag %d\n",
- m, rcall->id, rcall->tag);
- kfree(rcall);
+ if (m->req->status != REQ_STATUS_FLSH) {
+ list_del(&m->req->req_list);
+ m->req->status = REQ_STATUS_RCVD;
}
+
+ process_request(m, m->req);
+
+ if (m->req->status != REQ_STATUS_FLSH)
+ p9_conn_rpc_cb(m->client, m->req);
+
+ m->req = NULL;
}
if (!list_empty(&m->req_list)) {
@@ -470,7 +474,6 @@
clear_bit(Rworksched, &m->wsched);
return;
-
error:
p9_conn_cancel(m, err);
clear_bit(Rworksched, &m->wsched);