[PATCH] v9fs: new multiplexer implementation
New multiplexer implementation. Decreases the number of kernel threads
required. Better handling when the user process receives a signal.
Signed-off-by: Latchesar Ionkov <lucho@ionkov.net>
Cc: Eric Van Hensbergen <ericvh@ericvh.myip.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/fs/9p/conv.c b/fs/9p/conv.c
index 18121af..1b9b15d 100644
--- a/fs/9p/conv.c
+++ b/fs/9p/conv.c
@@ -208,7 +208,7 @@
len = buf_get_int16(buf);
if (!buf_check_overflow(buf) && buf_check_size(buf, len) &&
- buf_check_size(sbuf, len+1)) {
+ buf_check_size(sbuf, len + 1)) {
memcpy(sbuf->p, buf->p, len);
sbuf->p[len] = 0;
@@ -252,13 +252,12 @@
/**
* v9fs_size_stat - calculate the size of a variable length stat struct
- * @v9ses: session information
* @stat: metadata (stat) structure
+ * @extended: non-zero if 9P2000.u
*
*/
-static int v9fs_size_stat(struct v9fs_session_info *v9ses,
- struct v9fs_stat *stat)
+static int v9fs_size_stat(struct v9fs_stat *stat, int extended)
{
int size = 0;
@@ -288,7 +287,7 @@
if (stat->muid)
size += strlen(stat->muid);
- if (v9ses->extended) {
+ if (extended) {
size += 4 + /* n_uid[4] */
4 + /* n_gid[4] */
4 + /* n_muid[4] */
@@ -302,15 +301,14 @@
/**
* serialize_stat - safely format a stat structure for transmission
- * @v9ses: session info
* @stat: metadata (stat) structure
* @bufp: buffer to serialize structure into
+ * @extended: non-zero if 9P2000.u
*
*/
static int
-serialize_stat(struct v9fs_session_info *v9ses, struct v9fs_stat *stat,
- struct cbuf *bufp)
+serialize_stat(struct v9fs_stat *stat, struct cbuf *bufp, int extended)
{
buf_put_int16(bufp, stat->size);
buf_put_int16(bufp, stat->type);
@@ -328,7 +326,7 @@
buf_put_string(bufp, stat->gid);
buf_put_string(bufp, stat->muid);
- if (v9ses->extended) {
+ if (extended) {
buf_put_string(bufp, stat->extension);
buf_put_int32(bufp, stat->n_uid);
buf_put_int32(bufp, stat->n_gid);
@@ -343,16 +341,16 @@
/**
* deserialize_stat - safely decode a recieved metadata (stat) structure
- * @v9ses: session info
* @bufp: buffer to deserialize
* @stat: metadata (stat) structure
* @dbufp: buffer to deserialize variable strings into
+ * @extended: non-zero if 9P2000.u
*
*/
static inline int
-deserialize_stat(struct v9fs_session_info *v9ses, struct cbuf *bufp,
- struct v9fs_stat *stat, struct cbuf *dbufp)
+deserialize_stat(struct cbuf *bufp, struct v9fs_stat *stat,
+ struct cbuf *dbufp, int extended)
{
stat->size = buf_get_int16(bufp);
@@ -370,7 +368,7 @@
stat->gid = buf_get_stringb(bufp, dbufp);
stat->muid = buf_get_stringb(bufp, dbufp);
- if (v9ses->extended) {
+ if (extended) {
stat->extension = buf_get_stringb(bufp, dbufp);
stat->n_uid = buf_get_int32(bufp);
stat->n_gid = buf_get_int32(bufp);
@@ -385,20 +383,20 @@
/**
* deserialize_statb - wrapper for decoding a received metadata structure
- * @v9ses: session info
* @bufp: buffer to deserialize
* @dbufp: buffer to deserialize variable strings into
+ * @extended: non-zero if 9P2000.u
*
*/
-static inline struct v9fs_stat *deserialize_statb(struct v9fs_session_info
- *v9ses, struct cbuf *bufp,
- struct cbuf *dbufp)
+static inline struct v9fs_stat *deserialize_statb(struct cbuf *bufp,
+ struct cbuf *dbufp,
+ int extended)
{
struct v9fs_stat *ret = buf_alloc(dbufp, sizeof(struct v9fs_stat));
if (ret) {
- int n = deserialize_stat(v9ses, bufp, ret, dbufp);
+ int n = deserialize_stat(bufp, ret, dbufp, extended);
if (n <= 0)
return NULL;
}
@@ -408,17 +406,16 @@
/**
* v9fs_deserialize_stat - decode a received metadata structure
- * @v9ses: session info
* @buf: buffer to deserialize
* @buflen: length of received buffer
* @stat: metadata structure to decode into
* @statlen: length of destination metadata structure
+ * @extended: non-zero if 9P2000.u
*
*/
-int
-v9fs_deserialize_stat(struct v9fs_session_info *v9ses, void *buf,
- u32 buflen, struct v9fs_stat *stat, u32 statlen)
+int v9fs_deserialize_stat(void *buf, u32 buflen, struct v9fs_stat *stat,
+ u32 statlen, int extended)
{
struct cbuf buffer;
struct cbuf *bufp = &buffer;
@@ -429,11 +426,10 @@
buf_init(dbufp, (char *)stat + sizeof(struct v9fs_stat),
statlen - sizeof(struct v9fs_stat));
- return deserialize_stat(v9ses, bufp, stat, dbufp);
+ return deserialize_stat(bufp, stat, dbufp, extended);
}
-static inline int
-v9fs_size_fcall(struct v9fs_session_info *v9ses, struct v9fs_fcall *fcall)
+static inline int v9fs_size_fcall(struct v9fs_fcall *fcall, int extended)
{
int size = 4 + 1 + 2; /* size[4] msg[1] tag[2] */
int i = 0;
@@ -485,7 +481,7 @@
break;
case TWSTAT: /* fid[4] stat[n] */
fcall->params.twstat.stat->size =
- v9fs_size_stat(v9ses, fcall->params.twstat.stat);
+ v9fs_size_stat(fcall->params.twstat.stat, extended);
size += 4 + 2 + 2 + fcall->params.twstat.stat->size;
}
return size;
@@ -493,16 +489,16 @@
/*
* v9fs_serialize_fcall - marshall fcall struct into a packet
- * @v9ses: session information
* @fcall: structure to convert
* @data: buffer to serialize fcall into
* @datalen: length of buffer to serialize fcall into
+ * @extended: non-zero if 9P2000.u
*
*/
int
-v9fs_serialize_fcall(struct v9fs_session_info *v9ses, struct v9fs_fcall *fcall,
- void *data, u32 datalen)
+v9fs_serialize_fcall(struct v9fs_fcall *fcall, void *data, u32 datalen,
+ int extended)
{
int i = 0;
struct v9fs_stat *stat = NULL;
@@ -516,7 +512,7 @@
return -EINVAL;
}
- fcall->size = v9fs_size_fcall(v9ses, fcall);
+ fcall->size = v9fs_size_fcall(fcall, extended);
buf_put_int32(bufp, fcall->size);
buf_put_int8(bufp, fcall->id);
@@ -591,31 +587,31 @@
stat = fcall->params.twstat.stat;
buf_put_int16(bufp, stat->size + 2);
- serialize_stat(v9ses, stat, bufp);
+ serialize_stat(stat, bufp, extended);
break;
}
- if (buf_check_overflow(bufp))
+ if (buf_check_overflow(bufp)) {
+ dprintk(DEBUG_ERROR, "buffer overflow\n");
return -EIO;
+ }
return fcall->size;
}
/**
* deserialize_fcall - unmarshal a response
- * @v9ses: session information
- * @msgsize: size of rcall message
* @buf: recieved buffer
* @buflen: length of received buffer
* @rcall: fcall structure to populate
* @rcalllen: length of fcall structure to populate
+ * @extended: non-zero if 9P2000.u
*
*/
int
-v9fs_deserialize_fcall(struct v9fs_session_info *v9ses, u32 msgsize,
- void *buf, u32 buflen, struct v9fs_fcall *rcall,
- int rcalllen)
+v9fs_deserialize_fcall(void *buf, u32 buflen, struct v9fs_fcall *rcall,
+ int rcalllen, int extended)
{
struct cbuf buffer;
@@ -628,7 +624,7 @@
buf_init(dbufp, (char *)rcall + sizeof(struct v9fs_fcall),
rcalllen - sizeof(struct v9fs_fcall));
- rcall->size = msgsize;
+ rcall->size = buf_get_int32(bufp);
rcall->id = buf_get_int8(bufp);
rcall->tag = buf_get_int16(bufp);
@@ -651,6 +647,12 @@
break;
case RWALK:
rcall->params.rwalk.nwqid = buf_get_int16(bufp);
+ if (rcall->params.rwalk.nwqid > 16) {
+ eprintk(KERN_ERR, "Rwalk with more than 16 qids: %d\n",
+ rcall->params.rwalk.nwqid);
+ return -EPROTO;
+ }
+
rcall->params.rwalk.wqids = buf_alloc(dbufp,
rcall->params.rwalk.nwqid * sizeof(struct v9fs_qid));
if (rcall->params.rwalk.wqids)
@@ -690,19 +692,21 @@
case RSTAT:
buf_get_int16(bufp);
rcall->params.rstat.stat =
- deserialize_statb(v9ses, bufp, dbufp);
+ deserialize_statb(bufp, dbufp, extended);
break;
case RWSTAT:
break;
case RERROR:
rcall->params.rerror.error = buf_get_stringb(bufp, dbufp);
- if (v9ses->extended)
+ if (extended)
rcall->params.rerror.errno = buf_get_int16(bufp);
break;
}
- if (buf_check_overflow(bufp) || buf_check_overflow(dbufp))
+ if (buf_check_overflow(bufp) || buf_check_overflow(dbufp)) {
+ dprintk(DEBUG_ERROR, "buffer overflow\n");
return -EIO;
+ }
return rcall->size;
}