Merge tag 'afs-next-20191121' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs

Pull AFS updates from David Howells:
 "Minor cleanups and fix:

   - Minor fix to make some debugging statements display information
     from the correct iov_iter.

   - Rename some members and variables to make things more obvious or
     consistent.

   - Provide a helper to wrap increments of the usage count on the
     afs_read struct.

   - Use scnprintf() to print into a stack buffer rather than sprintf().

   - Remove some set but unused variables"

* tag 'afs-next-20191121' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
  afs: Remove set but not used variable 'ret'
  afs: Remove set but not used variables 'before', 'after'
  afs: xattr: use scnprintf
  afs: Introduce an afs_get_read() refcount helper
  afs: Rename desc -> req in afs_fetch_data()
  afs: Switch the naming of call->iter and call->_iter
  afs: Use call->_iter not &call->iter in debugging statements

fs/afs/cmservice.c

@@ -342,14 +342,14 @@ static int afs_deliver_cb_callback(struct afs_call *call)
 		if (call->count2 != call->count && call->count2 != 0)
 			return afs_protocol_error(call, -EBADMSG,
 						  afs_eproto_cb_count);
-		call->_iter = &call->iter;
-		iov_iter_discard(&call->iter, READ, call->count2 * 3 * 4);
+		call->iter = &call->def_iter;
+		iov_iter_discard(&call->def_iter, READ, call->count2 * 3 * 4);
 		call->unmarshall++;
 
 		/* Fall through */
 	case 4:
 		_debug("extract discard %zu/%u",
-		       iov_iter_count(&call->iter), call->count2 * 3 * 4);
+		       iov_iter_count(call->iter), call->count2 * 3 * 4);
 
 		ret = afs_extract_data(call, false);
 		if (ret < 0)

fs/afs/dir_edit.c

@@ -68,13 +68,11 @@ static int afs_find_contig_bits(union afs_xdr_dir_block *block, unsigned int nr_
 static void afs_set_contig_bits(union afs_xdr_dir_block *block,
 				int bit, unsigned int nr_slots)
 {
-	u64 mask, before, after;
+	u64 mask;
 
 	mask = (1 << nr_slots) - 1;
 	mask <<= bit;
 
-	before = *(u64 *)block->hdr.bitmap;
-
 	block->hdr.bitmap[0] |= (u8)(mask >> 0 * 8);
 	block->hdr.bitmap[1] |= (u8)(mask >> 1 * 8);
 	block->hdr.bitmap[2] |= (u8)(mask >> 2 * 8);
@@ -83,8 +81,6 @@ static void afs_set_contig_bits(union afs_xdr_dir_block *block,
 	block->hdr.bitmap[5] |= (u8)(mask >> 5 * 8);
 	block->hdr.bitmap[6] |= (u8)(mask >> 6 * 8);
 	block->hdr.bitmap[7] |= (u8)(mask >> 7 * 8);
-
-	after = *(u64 *)block->hdr.bitmap;
 }
 
 /*
@@ -93,13 +89,11 @@ static void afs_set_contig_bits(union afs_xdr_dir_block *block,
 static void afs_clear_contig_bits(union afs_xdr_dir_block *block,
 				  int bit, unsigned int nr_slots)
 {
-	u64 mask, before, after;
+	u64 mask;
 
 	mask = (1 << nr_slots) - 1;
 	mask <<= bit;
 
-	before = *(u64 *)block->hdr.bitmap;
-
 	block->hdr.bitmap[0] &= ~(u8)(mask >> 0 * 8);
 	block->hdr.bitmap[1] &= ~(u8)(mask >> 1 * 8);
 	block->hdr.bitmap[2] &= ~(u8)(mask >> 2 * 8);
@@ -108,8 +102,6 @@ static void afs_clear_contig_bits(union afs_xdr_dir_block *block,
 	block->hdr.bitmap[5] &= ~(u8)(mask >> 5 * 8);
 	block->hdr.bitmap[6] &= ~(u8)(mask >> 6 * 8);
 	block->hdr.bitmap[7] &= ~(u8)(mask >> 7 * 8);
-
-	after = *(u64 *)block->hdr.bitmap;
 }
 
 /*

fs/afs/file.c

@@ -223,7 +223,7 @@ static void afs_file_readpage_read_complete(struct page *page,
 /*
  * Fetch file data from the volume.
  */
-int afs_fetch_data(struct afs_vnode *vnode, struct key *key, struct afs_read *desc)
+int afs_fetch_data(struct afs_vnode *vnode, struct key *key, struct afs_read *req)
 {
 	struct afs_fs_cursor fc;
 	struct afs_status_cb *scb;
@@ -246,7 +246,7 @@ int afs_fetch_data(struct afs_vnode *vnode, struct key *key, struct afs_read *de
 
 		while (afs_select_fileserver(&fc)) {
 			fc.cb_break = afs_calc_vnode_cb_break(vnode);
-			afs_fs_fetch_data(&fc, scb, desc);
+			afs_fs_fetch_data(&fc, scb, req);
 		}
 
 		afs_check_for_remote_deletion(&fc, vnode);
@@ -257,7 +257,7 @@ int afs_fetch_data(struct afs_vnode *vnode, struct key *key, struct afs_read *de
 
 	if (ret == 0) {
 		afs_stat_v(vnode, n_fetches);
-		atomic_long_add(desc->actual_len,
+		atomic_long_add(req->actual_len,
 				&afs_v2net(vnode)->n_fetch_bytes);
 	}
 

fs/afs/fsclient.c

@@ -323,7 +323,7 @@ static int afs_deliver_fs_fetch_data(struct afs_call *call)
 	int ret;
 
 	_enter("{%u,%zu/%llu}",
-	       call->unmarshall, iov_iter_count(&call->iter), req->actual_len);
+	       call->unmarshall, iov_iter_count(call->iter), req->actual_len);
 
 	switch (call->unmarshall) {
 	case 0:
@@ -363,14 +363,14 @@ static int afs_deliver_fs_fetch_data(struct afs_call *call)
 		call->bvec[0].bv_len = size;
 		call->bvec[0].bv_offset = req->offset;
 		call->bvec[0].bv_page = req->pages[req->index];
-		iov_iter_bvec(&call->iter, READ, call->bvec, 1, size);
+		iov_iter_bvec(&call->def_iter, READ, call->bvec, 1, size);
 		ASSERTCMP(size, <=, PAGE_SIZE);
 		/* Fall through */
 
 		/* extract the returned data */
 	case 2:
 		_debug("extract data %zu/%llu",
-		       iov_iter_count(&call->iter), req->remain);
+		       iov_iter_count(call->iter), req->remain);
 
 		ret = afs_extract_data(call, true);
 		if (ret < 0)
@@ -398,7 +398,7 @@ static int afs_deliver_fs_fetch_data(struct afs_call *call)
 
 	case 3:
 		_debug("extract discard %zu/%llu",
-		       iov_iter_count(&call->iter), req->actual_len - req->len);
+		       iov_iter_count(call->iter), req->actual_len - req->len);
 
 		ret = afs_extract_data(call, true);
 		if (ret < 0)
@@ -490,7 +490,7 @@ static int afs_fs_fetch_data64(struct afs_fs_cursor *fc,
 	call->key = fc->key;
 	call->out_scb = scb;
 	call->out_volsync = NULL;
-	call->read_request = req;
+	call->read_request = afs_get_read(req);
 
 	/* marshall the parameters */
 	bp = call->request;
@@ -503,7 +503,6 @@ static int afs_fs_fetch_data64(struct afs_fs_cursor *fc,
 	bp[6] = 0;
 	bp[7] = htonl(lower_32_bits(req->len));
 
-	refcount_inc(&req->usage);
 	afs_use_fs_server(call, fc->cbi);
 	trace_afs_make_fs_call(call, &vnode->fid);
 	afs_set_fc_call(call, fc);
@@ -540,7 +539,7 @@ int afs_fs_fetch_data(struct afs_fs_cursor *fc,
 	call->key = fc->key;
 	call->out_scb = scb;
 	call->out_volsync = NULL;
-	call->read_request = req;
+	call->read_request = afs_get_read(req);
 
 	/* marshall the parameters */
 	bp = call->request;
@@ -551,7 +550,6 @@ int afs_fs_fetch_data(struct afs_fs_cursor *fc,
 	bp[4] = htonl(lower_32_bits(req->pos));
 	bp[5] = htonl(lower_32_bits(req->len));
 
-	refcount_inc(&req->usage);
 	afs_use_fs_server(call, fc->cbi);
 	trace_afs_make_fs_call(call, &vnode->fid);
 	afs_set_fc_call(call, fc);
@@ -1852,7 +1850,7 @@ static int afs_deliver_fs_get_capabilities(struct afs_call *call)
 	u32 count;
 	int ret;
 
-	_enter("{%u,%zu}", call->unmarshall, iov_iter_count(&call->iter));
+	_enter("{%u,%zu}", call->unmarshall, iov_iter_count(call->iter));
 
 	switch (call->unmarshall) {
 	case 0:

fs/afs/internal.h

@@ -115,9 +115,9 @@ struct afs_call {
 	struct afs_vnode	*lvnode;	/* vnode being locked */
 	void			*request;	/* request data (first part) */
 	struct address_space	*mapping;	/* Pages being written from */
-	struct iov_iter		iter;		/* Buffer iterator */
-	struct iov_iter		*_iter;		/* Iterator currently in use */
-	union {	/* Convenience for ->iter */
+	struct iov_iter		def_iter;	/* Default buffer/data iterator */
+	struct iov_iter		*iter;		/* Iterator currently in use */
+	union {	/* Convenience for ->def_iter */
 		struct kvec	kvec[1];
 		struct bio_vec	bvec[1];
 	};
@@ -934,6 +934,12 @@ extern int afs_fetch_data(struct afs_vnode *, struct key *, struct afs_read *);
 extern int afs_page_filler(void *, struct page *);
 extern void afs_put_read(struct afs_read *);
 
+static inline struct afs_read *afs_get_read(struct afs_read *req)
+{
+	refcount_inc(&req->usage);
+	return req;
+}
+
 /*
  * flock.c
  */
@@ -1136,7 +1142,7 @@ static inline void afs_extract_begin(struct afs_call *call, void *buf, size_t si
 {
 	call->kvec[0].iov_base = buf;
 	call->kvec[0].iov_len = size;
-	iov_iter_kvec(&call->iter, READ, call->kvec, 1, size);
+	iov_iter_kvec(&call->def_iter, READ, call->kvec, 1, size);
 }
 
 static inline void afs_extract_to_tmp(struct afs_call *call)
@@ -1151,7 +1157,7 @@ static inline void afs_extract_to_tmp64(struct afs_call *call)
 
 static inline void afs_extract_discard(struct afs_call *call, size_t size)
 {
-	iov_iter_discard(&call->iter, READ, size);
+	iov_iter_discard(&call->def_iter, READ, size);
 }
 
 static inline void afs_extract_to_buf(struct afs_call *call, size_t size)

fs/afs/rxrpc.c

@@ -152,7 +152,7 @@ static struct afs_call *afs_alloc_call(struct afs_net *net,
 	INIT_WORK(&call->async_work, afs_process_async_call);
 	init_waitqueue_head(&call->waitq);
 	spin_lock_init(&call->state_lock);
-	call->_iter = &call->iter;
+	call->iter = &call->def_iter;
 
 	o = atomic_inc_return(&net->nr_outstanding_calls);
 	trace_afs_call(call, afs_call_trace_alloc, 1, o,
@@ -513,12 +513,12 @@ static void afs_deliver_to_call(struct afs_call *call)
 	       state == AFS_CALL_SV_AWAIT_ACK
 	       ) {
 		if (state == AFS_CALL_SV_AWAIT_ACK) {
-			iov_iter_kvec(&call->iter, READ, NULL, 0, 0);
+			iov_iter_kvec(&call->def_iter, READ, NULL, 0, 0);
 			ret = rxrpc_kernel_recv_data(call->net->socket,
-						     call->rxcall, &call->iter,
+						     call->rxcall, &call->def_iter,
 						     false, &remote_abort,
 						     &call->service_id);
-			trace_afs_receive_data(call, &call->iter, false, ret);
+			trace_afs_receive_data(call, &call->def_iter, false, ret);
 
 			if (ret == -EINPROGRESS || ret == -EAGAIN)
 				return;
@@ -859,7 +859,7 @@ static int afs_deliver_cm_op_id(struct afs_call *call)
 {
 	int ret;
 
-	_enter("{%zu}", iov_iter_count(call->_iter));
+	_enter("{%zu}", iov_iter_count(call->iter));
 
 	/* the operation ID forms the first four bytes of the request data */
 	ret = afs_extract_data(call, true);
@@ -975,7 +975,7 @@ void afs_send_simple_reply(struct afs_call *call, const void *buf, size_t len)
 int afs_extract_data(struct afs_call *call, bool want_more)
 {
 	struct afs_net *net = call->net;
-	struct iov_iter *iter = call->_iter;
+	struct iov_iter *iter = call->iter;
 	enum afs_call_state state;
 	u32 remote_abort = 0;
 	int ret;

fs/afs/server.c

@@ -151,7 +151,7 @@ static struct afs_server *afs_install_server(struct afs_net *net,
 	const struct afs_addr_list *alist;
 	struct afs_server *server;
 	struct rb_node **pp, *p;
-	int ret = -EEXIST, diff;
+	int diff;
 
 	_enter("%p", candidate);
 
@@ -196,7 +196,6 @@ static struct afs_server *afs_install_server(struct afs_net *net,
 		hlist_add_head_rcu(&server->addr6_link, &net->fs_addresses6);
 
 	write_sequnlock(&net->fs_addr_lock);
-	ret = 0;
 
 exists:
 	afs_get_server(server, afs_server_trace_get_install);

fs/afs/vlclient.c

@@ -185,7 +185,7 @@ static int afs_deliver_vl_get_addrs_u(struct afs_call *call)
 	int i, ret;
 
 	_enter("{%u,%zu/%u}",
-	       call->unmarshall, iov_iter_count(call->_iter), call->count);
+	       call->unmarshall, iov_iter_count(call->iter), call->count);
 
 	switch (call->unmarshall) {
 	case 0:
@@ -316,7 +316,7 @@ static int afs_deliver_vl_get_capabilities(struct afs_call *call)
 	int ret;
 
 	_enter("{%u,%zu/%u}",
-	       call->unmarshall, iov_iter_count(call->_iter), call->count);
+	       call->unmarshall, iov_iter_count(call->iter), call->count);
 
 	switch (call->unmarshall) {
 	case 0:
@@ -425,7 +425,7 @@ static int afs_deliver_yfsvl_get_endpoints(struct afs_call *call)
 	int ret;
 
 	_enter("{%u,%zu,%u}",
-	       call->unmarshall, iov_iter_count(call->_iter), call->count2);
+	       call->unmarshall, iov_iter_count(call->iter), call->count2);
 
 	switch (call->unmarshall) {
 	case 0:

fs/afs/xattr.c

@@ -228,11 +228,11 @@ static int afs_xattr_get_yfs(const struct xattr_handler *handler,
 		break;
 	case 1:
 		data = buf;
-		dsize = snprintf(buf, sizeof(buf), "%u", yacl->inherit_flag);
+		dsize = scnprintf(buf, sizeof(buf), "%u", yacl->inherit_flag);
 		break;
 	case 2:
 		data = buf;
-		dsize = snprintf(buf, sizeof(buf), "%u", yacl->num_cleaned);
+		dsize = scnprintf(buf, sizeof(buf), "%u", yacl->num_cleaned);
 		break;
 	case 3:
 		data = yacl->vol_acl->data;
@@ -370,13 +370,15 @@ static int afs_xattr_get_fid(const struct xattr_handler *handler,
 	/* The volume ID is 64-bit, the vnode ID is 96-bit and the
 	 * uniquifier is 32-bit.
 	 */
-	len = sprintf(text, "%llx:", vnode->fid.vid);
+	len = scnprintf(text, sizeof(text), "%llx:", vnode->fid.vid);
 	if (vnode->fid.vnode_hi)
-		len += sprintf(text + len, "%x%016llx",
+		len += scnprintf(text + len, sizeof(text) - len, "%x%016llx",
 				vnode->fid.vnode_hi, vnode->fid.vnode);
 	else
-		len += sprintf(text + len, "%llx", vnode->fid.vnode);
-	len += sprintf(text + len, ":%x", vnode->fid.unique);
+		len += scnprintf(text + len, sizeof(text) - len, "%llx",
+				 vnode->fid.vnode);
+	len += scnprintf(text + len, sizeof(text) - len, ":%x",
+			 vnode->fid.unique);
 
 	if (size == 0)
 		return len;

fs/afs/yfsclient.c

@@ -441,7 +441,7 @@ static int yfs_deliver_fs_fetch_data64(struct afs_call *call)
 	int ret;
 
 	_enter("{%u,%zu/%llu}",
-	       call->unmarshall, iov_iter_count(&call->iter), req->actual_len);
+	       call->unmarshall, iov_iter_count(call->iter), req->actual_len);
 
 	switch (call->unmarshall) {
 	case 0:
@@ -476,14 +476,14 @@ static int yfs_deliver_fs_fetch_data64(struct afs_call *call)
 		call->bvec[0].bv_len = size;
 		call->bvec[0].bv_offset = req->offset;
 		call->bvec[0].bv_page = req->pages[req->index];
-		iov_iter_bvec(&call->iter, READ, call->bvec, 1, size);
+		iov_iter_bvec(&call->def_iter, READ, call->bvec, 1, size);
 		ASSERTCMP(size, <=, PAGE_SIZE);
 		/* Fall through */
 
 		/* extract the returned data */
 	case 2:
 		_debug("extract data %zu/%llu",
-		       iov_iter_count(&call->iter), req->remain);
+		       iov_iter_count(call->iter), req->remain);
 
 		ret = afs_extract_data(call, true);
 		if (ret < 0)
@@ -511,7 +511,7 @@ static int yfs_deliver_fs_fetch_data64(struct afs_call *call)
 
 	case 3:
 		_debug("extract discard %zu/%llu",
-		       iov_iter_count(&call->iter), req->actual_len - req->len);
+		       iov_iter_count(call->iter), req->actual_len - req->len);
 
 		ret = afs_extract_data(call, true);
 		if (ret < 0)
@@ -605,7 +605,7 @@ int yfs_fs_fetch_data(struct afs_fs_cursor *fc, struct afs_status_cb *scb,
 	call->key = fc->key;
 	call->out_scb = scb;
 	call->out_volsync = NULL;
-	call->read_request = req;
+	call->read_request = afs_get_read(req);
 
 	/* marshall the parameters */
 	bp = call->request;
@@ -616,7 +616,6 @@ int yfs_fs_fetch_data(struct afs_fs_cursor *fc, struct afs_status_cb *scb,
 	bp = xdr_encode_u64(bp, req->len);
 	yfs_check_req(call, bp);
 
-	refcount_inc(&req->usage);
 	afs_use_fs_server(call, fc->cbi);
 	trace_afs_make_fs_call(call, &vnode->fid);
 	afs_set_fc_call(call, fc);