Commit 67dd8e44 authored by Dominique Martinet's avatar Dominique Martinet
Browse files

9p: roll p9_tag_remove into p9_req_put 

mempool prep commit removed the awkward kref usage which didn't
allow passing client pointer easily with the ref, so we no longer
need a separate function to remove the tag from idr.

This has the side benefit that it should be more robust in detecting
leaks: umount will now properly catch unfreed requests as they still
will be in the idr until the last ref is dropped

Link: https://lkml.kernel.org/r/20220712060801.2487140-1-asmadeus@codewreck.org


Signed-off-by: default avatarDominique Martinet <asmadeus@codewreck.org>
Reviewed-by: default avatarChristian Schoenebeck <linux_oss@crudebyte.com>
parent 8b11ff09

net/9p/client.c

+51 −50
Original line number Diff line number Diff line
@@ -298,7 +298,7 @@ p9_tag_alloc(struct p9_client *c, int8_t type, unsigned int max_size) 
	/* Init ref to two because in the general case there is one ref

	 * that is put asynchronously by a writer thread, one ref

	 * temporarily given by p9_tag_lookup and put by p9_client_cb

	 * in the recv thread, and one ref put by p9_tag_remove in the

	 * in the recv thread, and one ref put by p9_req_put in the

	 * main thread. The only exception is virtio that does not use

	 * p9_tag_lookup but does not have a writer thread either

	 * (the write happens synchronously in the request/zc_request
@@ -358,21 +358,22 @@ EXPORT_SYMBOL(p9_tag_lookup); 
 *

 * Context: Any context.

 */

static int p9_tag_remove(struct p9_client *c, struct p9_req_t *r)

static void p9_tag_remove(struct p9_client *c, struct p9_req_t *r)

{

	unsigned long flags;

	u16 tag = r->tc.tag;



	p9_debug(P9_DEBUG_MUX, "clnt %p req %p tag: %d\n", c, r, tag);

	p9_debug(P9_DEBUG_MUX, "freeing clnt %p req %p tag: %d\n", c, r, tag);

	spin_lock_irqsave(&c->lock, flags);

	idr_remove(&c->reqs, tag);

	spin_unlock_irqrestore(&c->lock, flags);

	return p9_req_put(c, r);

}



int p9_req_put(struct p9_client *c, struct p9_req_t *r)

{

	if (refcount_dec_and_test(&r->refcount)) {

		p9_tag_remove(c, r);



		p9_fcall_fini(&r->tc);

		p9_fcall_fini(&r->rc);

		kmem_cache_free(p9_req_cache, r);
@@ -397,7 +398,7 @@ static void p9_tag_cleanup(struct p9_client *c) 
	rcu_read_lock();

	idr_for_each_entry(&c->reqs, req, id) {

		pr_info("Tag %d still in use\n", id);

		if (p9_tag_remove(c, req) == 0)

		if (p9_req_put(c, req) == 0)

			pr_warn("Packet with tag %d has still references",

				req->tc.tag);

	}
@@ -670,7 +671,7 @@ static int p9_client_flush(struct p9_client *c, struct p9_req_t *oldreq) 
			c->trans_mod->cancelled(c, oldreq);

	}



	p9_tag_remove(c, req);

	p9_req_put(c, req);

	return 0;

}
@@ -704,7 +705,7 @@ static struct p9_req_t *p9_client_prepare_req(struct p9_client *c, 
	trace_9p_client_req(c, type, req->tc.tag);

	return req;

reterr:

	p9_tag_remove(c, req);

	p9_req_put(c, req);

	/* We have to put also the 2nd reference as it won't be used */

	p9_req_put(c, req);

	return ERR_PTR(err);
@@ -716,7 +717,7 @@ static struct p9_req_t *p9_client_prepare_req(struct p9_client *c, 
 * @type: type of request

 * @fmt: protocol format string (see protocol.c)

 *

 * Returns request structure (which client must free using p9_tag_remove)

 * Returns request structure (which client must free using p9_req_put)

 */



static struct p9_req_t *
@@ -794,7 +795,7 @@ p9_client_rpc(struct p9_client *c, int8_t type, const char *fmt, ...) 
	if (!err)

		return req;

reterr:

	p9_tag_remove(c, req);

	p9_req_put(c, req);

	return ERR_PTR(safe_errno(err));

}
@@ -809,7 +810,7 @@ p9_client_rpc(struct p9_client *c, int8_t type, const char *fmt, ...) 
 * @in_hdrlen: reader header size, This is the size of response protocol data

 * @fmt: protocol format string (see protocol.c)

 *

 * Returns request structure (which client must free using p9_tag_remove)

 * Returns request structure (which client must free using p9_req_put)

 */

static struct p9_req_t *p9_client_zc_rpc(struct p9_client *c, int8_t type,

					 struct iov_iter *uidata,
@@ -876,7 +877,7 @@ static struct p9_req_t *p9_client_zc_rpc(struct p9_client *c, int8_t type, 
	if (!err)

		return req;

reterr:

	p9_tag_remove(c, req);

	p9_req_put(c, req);

	return ERR_PTR(safe_errno(err));

}
@@ -1005,7 +1006,7 @@ static int p9_client_version(struct p9_client *c) 


error:

	kfree(version);

	p9_tag_remove(c, req);

	p9_req_put(c, req);



	return err;

}
@@ -1159,7 +1160,7 @@ struct p9_fid *p9_client_attach(struct p9_client *clnt, struct p9_fid *afid, 
	err = p9pdu_readf(&req->rc, clnt->proto_version, "Q", &qid);

	if (err) {

		trace_9p_protocol_dump(clnt, &req->rc);

		p9_tag_remove(clnt, req);

		p9_req_put(clnt, req);

		goto error;

	}
@@ -1168,7 +1169,7 @@ struct p9_fid *p9_client_attach(struct p9_client *clnt, struct p9_fid *afid, 


	memmove(&fid->qid, &qid, sizeof(struct p9_qid));



	p9_tag_remove(clnt, req);

	p9_req_put(clnt, req);

	return fid;



error:
@@ -1215,10 +1216,10 @@ struct p9_fid *p9_client_walk(struct p9_fid *oldfid, uint16_t nwname, 
	err = p9pdu_readf(&req->rc, clnt->proto_version, "R", &nwqids, &wqids);

	if (err) {

		trace_9p_protocol_dump(clnt, &req->rc);

		p9_tag_remove(clnt, req);

		p9_req_put(clnt, req);

		goto clunk_fid;

	}

	p9_tag_remove(clnt, req);

	p9_req_put(clnt, req);



	p9_debug(P9_DEBUG_9P, "<<< RWALK nwqid %d:\n", nwqids);
@@ -1294,7 +1295,7 @@ int p9_client_open(struct p9_fid *fid, int mode) 
	fid->iounit = iounit;



free_and_error:

	p9_tag_remove(clnt, req);

	p9_req_put(clnt, req);

error:

	return err;

}
@@ -1338,7 +1339,7 @@ int p9_client_create_dotl(struct p9_fid *ofid, const char *name, u32 flags, 
	ofid->iounit = iounit;



free_and_error:

	p9_tag_remove(clnt, req);

	p9_req_put(clnt, req);

error:

	return err;

}
@@ -1382,7 +1383,7 @@ int p9_client_fcreate(struct p9_fid *fid, const char *name, u32 perm, int mode, 
	fid->iounit = iounit;



free_and_error:

	p9_tag_remove(clnt, req);

	p9_req_put(clnt, req);

error:

	return err;

}
@@ -1416,7 +1417,7 @@ int p9_client_symlink(struct p9_fid *dfid, const char *name, 
		 qid->type, qid->path, qid->version);



free_and_error:

	p9_tag_remove(clnt, req);

	p9_req_put(clnt, req);

error:

	return err;

}
@@ -1436,7 +1437,7 @@ int p9_client_link(struct p9_fid *dfid, struct p9_fid *oldfid, const char *newna 
		return PTR_ERR(req);



	p9_debug(P9_DEBUG_9P, "<<< RLINK\n");

	p9_tag_remove(clnt, req);

	p9_req_put(clnt, req);

	return 0;

}

EXPORT_SYMBOL(p9_client_link);
@@ -1460,7 +1461,7 @@ int p9_client_fsync(struct p9_fid *fid, int datasync) 


	p9_debug(P9_DEBUG_9P, "<<< RFSYNC fid %d\n", fid->fid);



	p9_tag_remove(clnt, req);

	p9_req_put(clnt, req);



error:

	return err;
@@ -1488,7 +1489,7 @@ int p9_client_clunk(struct p9_fid *fid) 


	p9_debug(P9_DEBUG_9P, "<<< RCLUNK fid %d\n", fid->fid);



	p9_tag_remove(clnt, req);

	p9_req_put(clnt, req);

error:

	/* Fid is not valid even after a failed clunk

	 * If interrupted, retry once then give up and
@@ -1522,7 +1523,7 @@ int p9_client_remove(struct p9_fid *fid) 


	p9_debug(P9_DEBUG_9P, "<<< RREMOVE fid %d\n", fid->fid);



	p9_tag_remove(clnt, req);

	p9_req_put(clnt, req);

error:

	if (err == -ERESTARTSYS)

		p9_fid_put(fid);
@@ -1549,7 +1550,7 @@ int p9_client_unlinkat(struct p9_fid *dfid, const char *name, int flags) 
	}

	p9_debug(P9_DEBUG_9P, "<<< RUNLINKAT fid %d %s\n", dfid->fid, name);



	p9_tag_remove(clnt, req);

	p9_req_put(clnt, req);

error:

	return err;

}
@@ -1617,7 +1618,7 @@ p9_client_read_once(struct p9_fid *fid, u64 offset, struct iov_iter *to, 
			   "D", &count, &dataptr);

	if (*err) {

		trace_9p_protocol_dump(clnt, &req->rc);

		p9_tag_remove(clnt, req);

		p9_req_put(clnt, req);

		return 0;

	}

	if (rsize < count) {
@@ -1632,13 +1633,13 @@ p9_client_read_once(struct p9_fid *fid, u64 offset, struct iov_iter *to, 


		if (n != count) {

			*err = -EFAULT;

			p9_tag_remove(clnt, req);

			p9_req_put(clnt, req);

			return n;

		}

	} else {

		iov_iter_advance(to, count);

	}

	p9_tag_remove(clnt, req);

	p9_req_put(clnt, req);

	return count;

}

EXPORT_SYMBOL(p9_client_read_once);
@@ -1681,7 +1682,7 @@ p9_client_write(struct p9_fid *fid, u64 offset, struct iov_iter *from, int *err) 
		*err = p9pdu_readf(&req->rc, clnt->proto_version, "d", &count);

		if (*err) {

			trace_9p_protocol_dump(clnt, &req->rc);

			p9_tag_remove(clnt, req);

			p9_req_put(clnt, req);

			break;

		}

		if (rsize < count) {
@@ -1691,7 +1692,7 @@ p9_client_write(struct p9_fid *fid, u64 offset, struct iov_iter *from, int *err) 


		p9_debug(P9_DEBUG_9P, "<<< RWRITE count %d\n", count);



		p9_tag_remove(clnt, req);

		p9_req_put(clnt, req);

		iov_iter_advance(from, count);

		total += count;

		offset += count;
@@ -1726,7 +1727,7 @@ struct p9_wstat *p9_client_stat(struct p9_fid *fid) 
	err = p9pdu_readf(&req->rc, clnt->proto_version, "wS", &ignored, ret);

	if (err) {

		trace_9p_protocol_dump(clnt, &req->rc);

		p9_tag_remove(clnt, req);

		p9_req_put(clnt, req);

		goto error;

	}
@@ -1743,7 +1744,7 @@ struct p9_wstat *p9_client_stat(struct p9_fid *fid) 
		 from_kgid(&init_user_ns, ret->n_gid),

		 from_kuid(&init_user_ns, ret->n_muid));



	p9_tag_remove(clnt, req);

	p9_req_put(clnt, req);

	return ret;



error:
@@ -1779,7 +1780,7 @@ struct p9_stat_dotl *p9_client_getattr_dotl(struct p9_fid *fid, 
	err = p9pdu_readf(&req->rc, clnt->proto_version, "A", ret);

	if (err) {

		trace_9p_protocol_dump(clnt, &req->rc);

		p9_tag_remove(clnt, req);

		p9_req_put(clnt, req);

		goto error;

	}
@@ -1805,7 +1806,7 @@ struct p9_stat_dotl *p9_client_getattr_dotl(struct p9_fid *fid, 
		 ret->st_btime_sec, ret->st_btime_nsec,

		 ret->st_gen, ret->st_data_version);



	p9_tag_remove(clnt, req);

	p9_req_put(clnt, req);

	return ret;



error:
@@ -1877,7 +1878,7 @@ int p9_client_wstat(struct p9_fid *fid, struct p9_wstat *wst) 


	p9_debug(P9_DEBUG_9P, "<<< RWSTAT fid %d\n", fid->fid);



	p9_tag_remove(clnt, req);

	p9_req_put(clnt, req);

error:

	return err;

}
@@ -1909,7 +1910,7 @@ int p9_client_setattr(struct p9_fid *fid, struct p9_iattr_dotl *p9attr) 
		goto error;

	}

	p9_debug(P9_DEBUG_9P, "<<< RSETATTR fid %d\n", fid->fid);

	p9_tag_remove(clnt, req);

	p9_req_put(clnt, req);

error:

	return err;

}
@@ -1937,7 +1938,7 @@ int p9_client_statfs(struct p9_fid *fid, struct p9_rstatfs *sb) 
			  &sb->files, &sb->ffree, &sb->fsid, &sb->namelen);

	if (err) {

		trace_9p_protocol_dump(clnt, &req->rc);

		p9_tag_remove(clnt, req);

		p9_req_put(clnt, req);

		goto error;

	}
@@ -1946,7 +1947,7 @@ int p9_client_statfs(struct p9_fid *fid, struct p9_rstatfs *sb) 
		 fid->fid, sb->type, sb->bsize, sb->blocks, sb->bfree,

		 sb->bavail, sb->files, sb->ffree, sb->fsid, sb->namelen);



	p9_tag_remove(clnt, req);

	p9_req_put(clnt, req);

error:

	return err;

}
@@ -1974,7 +1975,7 @@ int p9_client_rename(struct p9_fid *fid, 


	p9_debug(P9_DEBUG_9P, "<<< RRENAME fid %d\n", fid->fid);



	p9_tag_remove(clnt, req);

	p9_req_put(clnt, req);

error:

	return err;

}
@@ -2004,7 +2005,7 @@ int p9_client_renameat(struct p9_fid *olddirfid, const char *old_name, 
	p9_debug(P9_DEBUG_9P, "<<< RRENAMEAT newdirfid %d new name %s\n",

		 newdirfid->fid, new_name);



	p9_tag_remove(clnt, req);

	p9_req_put(clnt, req);

error:

	return err;

}
@@ -2040,10 +2041,10 @@ struct p9_fid *p9_client_xattrwalk(struct p9_fid *file_fid, 
	err = p9pdu_readf(&req->rc, clnt->proto_version, "q", attr_size);

	if (err) {

		trace_9p_protocol_dump(clnt, &req->rc);

		p9_tag_remove(clnt, req);

		p9_req_put(clnt, req);

		goto clunk_fid;

	}

	p9_tag_remove(clnt, req);

	p9_req_put(clnt, req);

	p9_debug(P9_DEBUG_9P, "<<<  RXATTRWALK fid %d size %llu\n",

		 attr_fid->fid, *attr_size);

	return attr_fid;
@@ -2077,7 +2078,7 @@ int p9_client_xattrcreate(struct p9_fid *fid, const char *name, 
		goto error;

	}

	p9_debug(P9_DEBUG_9P, "<<< RXATTRCREATE fid %d\n", fid->fid);

	p9_tag_remove(clnt, req);

	p9_req_put(clnt, req);

error:

	return err;

}
@@ -2139,11 +2140,11 @@ int p9_client_readdir(struct p9_fid *fid, char *data, u32 count, u64 offset) 
	if (non_zc)

		memmove(data, dataptr, count);



	p9_tag_remove(clnt, req);

	p9_req_put(clnt, req);

	return count;



free_and_error:

	p9_tag_remove(clnt, req);

	p9_req_put(clnt, req);

error:

	return err;

}
@@ -2175,7 +2176,7 @@ int p9_client_mknod_dotl(struct p9_fid *fid, const char *name, int mode, 
		 qid->type, qid->path, qid->version);



error:

	p9_tag_remove(clnt, req);

	p9_req_put(clnt, req);

	return err;

}

EXPORT_SYMBOL(p9_client_mknod_dotl);
@@ -2205,7 +2206,7 @@ int p9_client_mkdir_dotl(struct p9_fid *fid, const char *name, int mode, 
		 qid->path, qid->version);



error:

	p9_tag_remove(clnt, req);

	p9_req_put(clnt, req);

	return err;

}

EXPORT_SYMBOL(p9_client_mkdir_dotl);
@@ -2237,7 +2238,7 @@ int p9_client_lock_dotl(struct p9_fid *fid, struct p9_flock *flock, u8 *status) 
	}

	p9_debug(P9_DEBUG_9P, "<<< RLOCK status %i\n", *status);

error:

	p9_tag_remove(clnt, req);

	p9_req_put(clnt, req);

	return err;

}

EXPORT_SYMBOL(p9_client_lock_dotl);
@@ -2274,7 +2275,7 @@ int p9_client_getlock_dotl(struct p9_fid *fid, struct p9_getlock *glock) 
		 glock->type, glock->start, glock->length,

		 glock->proc_id, glock->client_id);

error:

	p9_tag_remove(clnt, req);

	p9_req_put(clnt, req);

	return err;

}

EXPORT_SYMBOL(p9_client_getlock_dotl);
@@ -2300,7 +2301,7 @@ int p9_client_readlink(struct p9_fid *fid, char **target) 
	}

	p9_debug(P9_DEBUG_9P, "<<< RREADLINK target %s\n", *target);

error:

	p9_tag_remove(clnt, req);

	p9_req_put(clnt, req);

	return err;

}

EXPORT_SYMBOL(p9_client_readlink);