Commit f105da1a authored by David Howells's avatar David Howells
Browse files

afs: Don't truncate iter during data fetch 



Don't truncate the iterator to correspond to the actual data size when
fetching the data from the server - rather, pass the length we want to read
to rxrpc.

This will allow the clear-after-read code in future to simply clear the
remaining iterator capacity rather than having to reinitialise the
iterator.

Signed-off-by: default avatarDavid Howells <dhowells@redhat.com>
Tested-By: default avatarMarc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
cc: linux-cachefs@redhat.com
cc: linux-fsdevel@vger.kernel.org
Link: https://lore.kernel.org/r/158861249201.340223.13035445866976590375.stgit@warthog.procyon.org.uk/ # rfc
Link: https://lore.kernel.org/r/159465825061.1377938.14403904452300909320.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/160588531418.3465195.10712005940763063144.stgit@warthog.procyon.org.uk/ # rfc
Link: https://lore.kernel.org/r/161118148567.1232039.13380313332292947956.stgit@warthog.procyon.org.uk/ # rfc
Link: https://lore.kernel.org/r/161161044610.2537118.17908520793806837792.stgit@warthog.procyon.org.uk/ # v2
Link: https://lore.kernel.org/r/161340407907.1303470.6501394859511712746.stgit@warthog.procyon.org.uk/ # v3
Link: https://lore.kernel.org/r/161539551721.286939.14655713136572200716.stgit@warthog.procyon.org.uk/ # v4
Link: https://lore.kernel.org/r/161653807790.2770958.14034599989374173734.stgit@warthog.procyon.org.uk/ # v5
Link: https://lore.kernel.org/r/161789090823.6155.15673999934535049102.stgit@warthog.procyon.org.uk/ # v6
parent c69bf479

fs/afs/fsclient.c

+4 −2
Original line number Diff line number Diff line
@@ -305,8 +305,9 @@ static int afs_deliver_fs_fetch_data(struct afs_call *call) 
	unsigned int size;

	int ret;



	_enter("{%u,%zu/%llu}",

	       call->unmarshall, iov_iter_count(call->iter), req->actual_len);

	_enter("{%u,%zu,%zu/%llu}",

	       call->unmarshall, call->iov_len, iov_iter_count(call->iter),

	       req->actual_len);



	switch (call->unmarshall) {

	case 0:
@@ -343,6 +344,7 @@ static int afs_deliver_fs_fetch_data(struct afs_call *call) 
			size = PAGE_SIZE - req->offset;

		else

			size = req->remain;

		call->iov_len = size;

		call->bvec[0].bv_len = size;

		call->bvec[0].bv_offset = req->offset;

		call->bvec[0].bv_page = req->pages[req->index];

fs/afs/internal.h

+6 −0
Original line number Diff line number Diff line
@@ -104,6 +104,7 @@ struct afs_call { 
	struct afs_server	*server;	/* The fileserver record if fs op (pins ref) */

	struct afs_vlserver	*vlserver;	/* The vlserver record if vl op */

	void			*request;	/* request data (first part) */

	size_t			iov_len;	/* Size of *iter to be used */

	struct iov_iter		def_iter;	/* Default buffer/data iterator */

	struct iov_iter		*iter;		/* Iterator currently in use */

	union {	/* Convenience for ->def_iter */
@@ -1271,6 +1272,7 @@ static inline void afs_make_op_call(struct afs_operation *op, struct afs_call *c 


static inline void afs_extract_begin(struct afs_call *call, void *buf, size_t size)

{

	call->iov_len = size;

	call->kvec[0].iov_base = buf;

	call->kvec[0].iov_len = size;

	iov_iter_kvec(&call->def_iter, READ, call->kvec, 1, size);
@@ -1278,21 +1280,25 @@ static inline void afs_extract_begin(struct afs_call *call, void *buf, size_t si 


static inline void afs_extract_to_tmp(struct afs_call *call)

{

	call->iov_len = sizeof(call->tmp);

	afs_extract_begin(call, &call->tmp, sizeof(call->tmp));

}



static inline void afs_extract_to_tmp64(struct afs_call *call)

{

	call->iov_len = sizeof(call->tmp64);

	afs_extract_begin(call, &call->tmp64, sizeof(call->tmp64));

}



static inline void afs_extract_discard(struct afs_call *call, size_t size)

{

	call->iov_len = size;

	iov_iter_discard(&call->def_iter, READ, size);

}



static inline void afs_extract_to_buf(struct afs_call *call, size_t size)

{

	call->iov_len = size;

	afs_extract_begin(call, call->buffer, size);

}

fs/afs/rxrpc.c

+9 −4
Original line number Diff line number Diff line
@@ -363,6 +363,7 @@ void afs_make_call(struct afs_addr_cursor *ac, struct afs_call *call, gfp_t gfp) 
	struct rxrpc_call *rxcall;

	struct msghdr msg;

	struct kvec iov[1];

	size_t len;

	s64 tx_total_len;

	int ret;
@@ -466,9 +467,10 @@ void afs_make_call(struct afs_addr_cursor *ac, struct afs_call *call, gfp_t gfp) 
		rxrpc_kernel_abort_call(call->net->socket, rxcall,

					RX_USER_ABORT, ret, "KSD");

	} else {

		len = 0;

		iov_iter_kvec(&msg.msg_iter, READ, NULL, 0, 0);

		rxrpc_kernel_recv_data(call->net->socket, rxcall,

				       &msg.msg_iter, false,

				       &msg.msg_iter, &len, false,

				       &call->abort_code, &call->service_id);

		ac->abort_code = call->abort_code;

		ac->responded = true;
@@ -504,6 +506,7 @@ void afs_make_call(struct afs_addr_cursor *ac, struct afs_call *call, gfp_t gfp) 
static void afs_deliver_to_call(struct afs_call *call)

{

	enum afs_call_state state;

	size_t len;

	u32 abort_code, remote_abort = 0;

	int ret;
@@ -516,10 +519,11 @@ static void afs_deliver_to_call(struct afs_call *call) 
	       state == AFS_CALL_SV_AWAIT_ACK

	       ) {

		if (state == AFS_CALL_SV_AWAIT_ACK) {

			len = 0;

			iov_iter_kvec(&call->def_iter, READ, NULL, 0, 0);

			ret = rxrpc_kernel_recv_data(call->net->socket,

						     call->rxcall, &call->def_iter,

						     false, &remote_abort,

						     &len, false, &remote_abort,

						     &call->service_id);

			trace_afs_receive_data(call, &call->def_iter, false, ret);
@@ -929,10 +933,11 @@ int afs_extract_data(struct afs_call *call, bool want_more) 
	u32 remote_abort = 0;

	int ret;



	_enter("{%s,%zu},%d", call->type->name, iov_iter_count(iter), want_more);

	_enter("{%s,%zu,%zu},%d",

	       call->type->name, call->iov_len, iov_iter_count(iter), want_more);



	ret = rxrpc_kernel_recv_data(net->socket, call->rxcall, iter,

				     want_more, &remote_abort,

				     &call->iov_len, want_more, &remote_abort,

				     &call->service_id);

	if (ret == 0 || ret == -EAGAIN)

		return ret;

fs/afs/yfsclient.c

+4 −2
Original line number Diff line number Diff line
@@ -363,8 +363,9 @@ static int yfs_deliver_fs_fetch_data64(struct afs_call *call) 
	unsigned int size;

	int ret;



	_enter("{%u,%zu/%llu}",

	       call->unmarshall, iov_iter_count(call->iter), req->actual_len);

	_enter("{%u,%zu, %zu/%llu}",

	       call->unmarshall, call->iov_len, iov_iter_count(call->iter),

	       req->actual_len);



	switch (call->unmarshall) {

	case 0:
@@ -396,6 +397,7 @@ static int yfs_deliver_fs_fetch_data64(struct afs_call *call) 
			size = PAGE_SIZE - req->offset;

		else

			size = req->remain;

		call->iov_len = size;

		call->bvec[0].bv_len = size;

		call->bvec[0].bv_offset = req->offset;

		call->bvec[0].bv_page = req->pages[req->index];

include/net/af_rxrpc.h

+1 −1
Original line number Diff line number Diff line
@@ -53,7 +53,7 @@ int rxrpc_kernel_send_data(struct socket *, struct rxrpc_call *, 
			   struct msghdr *, size_t,

			   rxrpc_notify_end_tx_t);

int rxrpc_kernel_recv_data(struct socket *, struct rxrpc_call *,

			   struct iov_iter *, bool, u32 *, u16 *);

			   struct iov_iter *, size_t *, bool, u32 *, u16 *);

bool rxrpc_kernel_abort_call(struct socket *, struct rxrpc_call *,

			     u32, int, const char *);

void rxrpc_kernel_end_call(struct socket *, struct rxrpc_call *);