diff options
| -rw-r--r-- | net/rds/rdma.c | 104 |
1 files changed, 65 insertions, 39 deletions
diff --git a/net/rds/rdma.c b/net/rds/rdma.c index 334acdd32ab..caa4d9866d9 100644 --- a/net/rds/rdma.c +++ b/net/rds/rdma.c @@ -479,13 +479,38 @@ void rds_atomic_free_op(struct rm_atomic_op *ao) /* - * Count the number of pages needed to describe an incoming iovec. + * Count the number of pages needed to describe an incoming iovec array. */ -static int rds_rdma_pages(struct rds_rdma_args *args) +static int rds_rdma_pages(struct rds_iovec iov[], int nr_iovecs) +{ + int tot_pages = 0; + unsigned int nr_pages; + unsigned int i; + + /* figure out the number of pages in the vector */ + for (i = 0; i < nr_iovecs; i++) { + nr_pages = rds_pages_in_vec(&iov[i]); + if (nr_pages == 0) + return -EINVAL; + + tot_pages += nr_pages; + + /* + * nr_pages for one entry is limited to (UINT_MAX>>PAGE_SHIFT)+1, + * so tot_pages cannot overflow without first going negative. + */ + if (tot_pages < 0) + return -EINVAL; + } + + return tot_pages; +} + +int rds_rdma_extra_size(struct rds_rdma_args *args) { struct rds_iovec vec; struct rds_iovec __user *local_vec; - unsigned int tot_pages = 0; + int tot_pages = 0; unsigned int nr_pages; unsigned int i; @@ -507,16 +532,11 @@ static int rds_rdma_pages(struct rds_rdma_args *args) * nr_pages for one entry is limited to (UINT_MAX>>PAGE_SHIFT)+1, * so tot_pages cannot overflow without first going negative. */ - if ((int)tot_pages < 0) + if (tot_pages < 0) return -EINVAL; } - return tot_pages; -} - -int rds_rdma_extra_size(struct rds_rdma_args *args) -{ - return rds_rdma_pages(args) * sizeof(struct scatterlist); + return tot_pages * sizeof(struct scatterlist); } /* @@ -527,13 +547,12 @@ int rds_cmsg_rdma_args(struct rds_sock *rs, struct rds_message *rm, struct cmsghdr *cmsg) { struct rds_rdma_args *args; - struct rds_iovec vec; struct rm_rdma_op *op = &rm->rdma; int nr_pages; unsigned int nr_bytes; struct page **pages = NULL; - struct rds_iovec __user *local_vec; - unsigned int nr; + struct rds_iovec iovstack[UIO_FASTIOV], *iovs = iovstack; + int iov_size; unsigned int i, j; int ret = 0; @@ -553,7 +572,22 @@ int rds_cmsg_rdma_args(struct rds_sock *rs, struct rds_message *rm, goto out; } - nr_pages = rds_rdma_pages(args); + /* Check whether to allocate the iovec area */ + iov_size = args->nr_local * sizeof(struct rds_iovec); + if (args->nr_local > UIO_FASTIOV) { + iovs = sock_kmalloc(rds_rs_to_sk(rs), iov_size, GFP_KERNEL); + if (!iovs) { + ret = -ENOMEM; + goto out; + } + } + + if (copy_from_user(iovs, (struct rds_iovec __user *)(unsigned long) args->local_vec_addr, iov_size)) { + ret = -EFAULT; + goto out; + } + + nr_pages = rds_rdma_pages(iovs, args->nr_local); if (nr_pages < 0) { ret = -EINVAL; goto out; @@ -606,50 +640,40 @@ int rds_cmsg_rdma_args(struct rds_sock *rs, struct rds_message *rm, (unsigned long long)args->remote_vec.addr, op->op_rkey); - local_vec = (struct rds_iovec __user *)(unsigned long) args->local_vec_addr; - for (i = 0; i < args->nr_local; i++) { - if (copy_from_user(&vec, &local_vec[i], - sizeof(struct rds_iovec))) { - ret = -EFAULT; - goto out; - } - - nr = rds_pages_in_vec(&vec); - if (nr == 0) { - ret = -EINVAL; - goto out; - } + struct rds_iovec *iov = &iovs[i]; + /* don't need to check, rds_rdma_pages() verified nr will be +nonzero */ + unsigned int nr = rds_pages_in_vec(iov); - rs->rs_user_addr = vec.addr; - rs->rs_user_bytes = vec.bytes; + rs->rs_user_addr = iov->addr; + rs->rs_user_bytes = iov->bytes; /* If it's a WRITE operation, we want to pin the pages for reading. * If it's a READ operation, we need to pin the pages for writing. */ - ret = rds_pin_pages(vec.addr, nr, pages, !op->op_write); + ret = rds_pin_pages(iov->addr, nr, pages, !op->op_write); if (ret < 0) goto out; - rdsdebug("RDS: nr_bytes %u nr %u vec.bytes %llu vec.addr %llx\n", - nr_bytes, nr, vec.bytes, vec.addr); + rdsdebug("RDS: nr_bytes %u nr %u iov->bytes %llu iov->addr %llx\n", + nr_bytes, nr, iov->bytes, iov->addr); - nr_bytes += vec.bytes; + nr_bytes += iov->bytes; for (j = 0; j < nr; j++) { - unsigned int offset = vec.addr & ~PAGE_MASK; + unsigned int offset = iov->addr & ~PAGE_MASK; struct scatterlist *sg; sg = &op->op_sg[op->op_nents + j]; sg_set_page(sg, pages[j], - min_t(unsigned int, vec.bytes, PAGE_SIZE - offset), + min_t(unsigned int, iov->bytes, PAGE_SIZE - offset), offset); - rdsdebug("RDS: sg->offset %x sg->len %x vec.addr %llx vec.bytes %llu\n", - sg->offset, sg->length, vec.addr, vec.bytes); + rdsdebug("RDS: sg->offset %x sg->len %x iov->addr %llx iov->bytes %llu\n", + sg->offset, sg->length, iov->addr, iov->bytes); - vec.addr += sg->length; - vec.bytes -= sg->length; + iov->addr += sg->length; + iov->bytes -= sg->length; } op->op_nents += nr; @@ -665,6 +689,8 @@ int rds_cmsg_rdma_args(struct rds_sock *rs, struct rds_message *rm, op->op_bytes = nr_bytes; out: + if (iovs != iovstack) + sock_kfree_s(rds_rs_to_sk(rs), iovs, iov_size); kfree(pages); if (ret) rds_rdma_free_op(op); |