net/9p: Convert net/9p protocol dumps to tracepoints

This helps in more control over debugging.
root@qemu-img-64:~# ls /pass/123
ls: cannot access /pass/123: No such file or directory
root@qemu-img-64:~# cat /sys/kernel/debug/tracing/trace
# tracer: nop
#
#           TASK-PID    CPU#    TIMESTAMP  FUNCTION
#              | |       |          |         |
              ls-1536  [001]    70.928584: 9p_protocol_dump: clnt 18446612132784021504 P9_TWALK(tag = 1)
000: 16 00 00 00 6e 01 00 01 00 00 00 02 00 00 00 01
010: 00 03 00 31 32 33 00 00 00 ff ff ff ff 00 00 00

              ls-1536  [001]    70.928587: <stack trace>
 => trace_9p_protocol_dump
 => p9pdu_finalize
 => p9_client_rpc
 => p9_client_walk
 => v9fs_vfs_lookup
 => d_alloc_and_lookup
 => walk_component
 => path_lookupat
              ls-1536  [000]    70.929696: 9p_protocol_dump: clnt 18446612132784021504 P9_RLERROR(tag = 1)
000: 0b 00 00 00 07 01 00 02 00 00 00 4e 03 00 02 00
010: 00 00 00 00 03 00 02 00 00 00 00 00 ff 43 00 00

              ls-1536  [000]    70.929697: <stack trace>
 => trace_9p_protocol_dump
 => p9_client_rpc
 => p9_client_walk
 => v9fs_vfs_lookup
 => d_alloc_and_lookup
 => walk_component
 => path_lookupat
 => do_path_lookup

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
diff --git a/include/net/9p/client.h b/include/net/9p/client.h
index d479d7d..fc9b90b 100644
--- a/include/net/9p/client.h
+++ b/include/net/9p/client.h
@@ -240,8 +240,8 @@
 int p9_client_write(struct p9_fid *fid, char *data, const char __user *udata,
 							u64 offset, u32 count);
 int p9_client_readdir(struct p9_fid *fid, char *data, u32 count, u64 offset);
-int p9dirent_read(char *buf, int len, struct p9_dirent *dirent,
-							int proto_version);
+int p9dirent_read(struct p9_client *clnt, char *buf, int len,
+		  struct p9_dirent *dirent);
 struct p9_wstat *p9_client_stat(struct p9_fid *fid);
 int p9_client_wstat(struct p9_fid *fid, struct p9_wstat *wst);
 int p9_client_setattr(struct p9_fid *fid, struct p9_iattr_dotl *attr);
@@ -259,7 +259,7 @@
 void p9_client_cb(struct p9_client *c, struct p9_req_t *req);
 
 int p9_parse_header(struct p9_fcall *, int32_t *, int8_t *, int16_t *, int);
-int p9stat_read(char *, int, struct p9_wstat *, int);
+int p9stat_read(struct p9_client *, char *, int, struct p9_wstat *);
 void p9stat_free(struct p9_wstat *);
 
 int p9_is_proto_dotu(struct p9_client *clnt);