Commit 8e4c2eee authored by Christian Schoenebeck's avatar Christian Schoenebeck Committed by Dominique Martinet
Browse files

net/9p: distinguish zero-copy requests 

Add boolean `zc` member to struct p9_fcall to distinguish zero-copy
messages (not using the linear `sdata` buffer for message payload) from
regular messages (which do copy message payload to `sdata` before being
further processed).

This new member is appended to end of structure to avoid inserting huge
padding in generated layout.

Link: https://lkml.kernel.org/r/8f2a5c12a446c3b544da64e0b1550e1fb2d6f972.1669144861.git.linux_oss@crudebyte.com


Signed-off-by: default avatarChristian Schoenebeck <linux_oss@crudebyte.com>
Tested-by: default avatarStefano Stabellini <sstabellini@kernel.org>
Signed-off-by: default avatarDominique Martinet <asmadeus@codewreck.org>
parent f15e006b

include/net/9p/9p.h

+2 −0
Original line number Diff line number Diff line
@@ -531,6 +531,7 @@ struct p9_rstatfs { 
 * @offset: used by marshalling routines to track current position in buffer

 * @capacity: used by marshalling routines to track total malloc'd capacity

 * @sdata: payload

 * @zc: whether zero-copy is used

 *

 * &p9_fcall represents the structure for all 9P RPC

 * transactions.  Requests are packaged into fcalls, and reponses
@@ -549,6 +550,7 @@ struct p9_fcall { 


	struct kmem_cache *cache;

	u8 *sdata;

	bool zc;

};



int p9_errstr2errno(char *errstr, int len);

net/9p/client.c

+6 −0
Original line number Diff line number Diff line
@@ -685,6 +685,9 @@ p9_client_rpc(struct p9_client *c, int8_t type, const char *fmt, ...) 
	if (IS_ERR(req))

		return req;



	req->tc.zc = false;

	req->rc.zc = false;



	if (signal_pending(current)) {

		sigpending = 1;

		clear_thread_flag(TIF_SIGPENDING);
@@ -783,6 +786,9 @@ static struct p9_req_t *p9_client_zc_rpc(struct p9_client *c, int8_t type, 
	if (IS_ERR(req))

		return req;



	req->tc.zc = true;

	req->rc.zc = true;



	if (signal_pending(current)) {

		sigpending = 1;

		clear_thread_flag(TIF_SIGPENDING);