int rds_message_copy_from_user(struct rds_message *rm, struct iovec *first_iov,
size_t total_len)
{
unsigned long to_copy;
unsigned long iov_off;
unsigned long sg_off;
struct iovec *iov;
struct scatterlist *sg;
int ret = 0;
rm->m_inc.i_hdr.h_len = cpu_to_be32(total_len);
/*
* now allocate and copy in the data payload.
*/
sg = rm->data.op_sg;
iov = first_iov;
iov_off = 0;
sg_off = 0; /* Dear gcc, sg->page will be null from kzalloc. */
while (total_len) {
if (!sg_page(sg)) {
ret = rds_page_remainder_alloc(sg, total_len,
GFP_HIGHUSER);
if (ret)
goto out;
rm->data.op_nents++;
sg_off = 0;
}
while (iov_off == iov->iov_len) {
iov_off = 0;
iov++;
}
to_copy = min(iov->iov_len - iov_off, sg->length - sg_off);
to_copy = min_t(size_t, to_copy, total_len);
rdsdebug("copying %lu bytes from user iov [%p, %zu] + %lu to "
"sg [%p, %u, %u] + %lu\n",
to_copy, iov->iov_base, iov->iov_len, iov_off,
(void *)sg_page(sg), sg->offset, sg->length, sg_off);
ret = rds_page_copy_from_user(sg_page(sg), sg->offset + sg_off,
iov->iov_base + iov_off,
to_copy);
if (ret)
goto out;
iov_off += to_copy;
total_len -= to_copy;
sg_off += to_copy;
if (sg_off == sg->length)
sg++;
}
out:
return ret;
}
int rds_message_copy_from_user(struct rds_message *rm, struct iov_iter *from)
{
unsigned long to_copy, nbytes;
unsigned long sg_off;
struct scatterlist *sg;
int ret = 0;
rm->m_inc.i_hdr.h_len = cpu_to_be32(iov_iter_count(from));
/*
* now allocate and copy in the data payload.
*/
sg = rm->data.op_sg;
sg_off = 0; /* Dear gcc, sg->page will be null from kzalloc. */
while (iov_iter_count(from)) {
if (!sg_page(sg)) {
ret = rds_page_remainder_alloc(sg, iov_iter_count(from),
GFP_HIGHUSER);
if (ret)
return ret;
rm->data.op_nents++;
sg_off = 0;
}
to_copy = min_t(unsigned long, iov_iter_count(from),
sg->length - sg_off);
rds_stats_add(s_copy_from_user, to_copy);
nbytes = copy_page_from_iter(sg_page(sg), sg->offset + sg_off,
to_copy, from);
if (nbytes != to_copy)
return -EFAULT;
sg_off += to_copy;
if (sg_off == sg->length)
sg++;
}
return ret;
}