From 4f3b35c157e43107cc7e1f1aa06694e8b22e10bb Mon Sep 17 00:00:00 2001 From: Al Viro Date: Wed, 1 Apr 2015 19:57:53 -0400 Subject: net/9p: switch the guts of p9_client_{read,write}() to iov_iter ... and have get_user_pages_fast() mapping fewer pages than requested to generate a short read/write. Signed-off-by: Al Viro --- net/9p/protocol.c | 24 ++++++++---------------- 1 file changed, 8 insertions(+), 16 deletions(-) (limited to 'net/9p/protocol.c') diff --git a/net/9p/protocol.c b/net/9p/protocol.c index ab9127ec5b7a..e9d0f0c1a048 100644 --- a/net/9p/protocol.c +++ b/net/9p/protocol.c @@ -33,6 +33,7 @@ #include #include #include +#include #include #include #include "protocol.h" @@ -69,10 +70,11 @@ static size_t pdu_write(struct p9_fcall *pdu, const void *data, size_t size) } static size_t -pdu_write_u(struct p9_fcall *pdu, const char __user *udata, size_t size) +pdu_write_u(struct p9_fcall *pdu, struct iov_iter *from, size_t size) { size_t len = min(pdu->capacity - pdu->size, size); - if (copy_from_user(&pdu->sdata[pdu->size], udata, len)) + struct iov_iter i = *from; + if (copy_from_iter(&pdu->sdata[pdu->size], len, &i) != len) len = 0; pdu->size += len; @@ -437,23 +439,13 @@ p9pdu_vwritef(struct p9_fcall *pdu, int proto_version, const char *fmt, stbuf->extension, stbuf->n_uid, stbuf->n_gid, stbuf->n_muid); } break; - case 'D':{ - uint32_t count = va_arg(ap, uint32_t); - const void *data = va_arg(ap, const void *); - - errcode = p9pdu_writef(pdu, proto_version, "d", - count); - if (!errcode && pdu_write(pdu, data, count)) - errcode = -EFAULT; - } - break; - case 'U':{ + case 'V':{ int32_t count = va_arg(ap, int32_t); - const char __user *udata = - va_arg(ap, const void __user *); + struct iov_iter *from = + va_arg(ap, struct iov_iter *); errcode = p9pdu_writef(pdu, proto_version, "d", count); - if (!errcode && pdu_write_u(pdu, udata, count)) + if (!errcode && pdu_write_u(pdu, from, count)) errcode = -EFAULT; } break; -- cgit v1.2.3