diff options
Diffstat (limited to '')
| -rw-r--r-- | net/rds/rdma.c | 958 |
1 files changed, 958 insertions, 0 deletions
diff --git a/net/rds/rdma.c b/net/rds/rdma.c new file mode 100644 index 000000000..6f1a50d50 --- /dev/null +++ b/net/rds/rdma.c @@ -0,0 +1,958 @@ +/* + * Copyright (c) 2007, 2020 Oracle and/or its affiliates. + * + * This software is available to you under a choice of one of two + * licenses. You may choose to be licensed under the terms of the GNU + * General Public License (GPL) Version 2, available from the file + * COPYING in the main directory of this source tree, or the + * OpenIB.org BSD license below: + * + * Redistribution and use in source and binary forms, with or + * without modification, are permitted provided that the following + * conditions are met: + * + * - Redistributions of source code must retain the above + * copyright notice, this list of conditions and the following + * disclaimer. + * + * - Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following + * disclaimer in the documentation and/or other materials + * provided with the distribution. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + * + */ +#include <linux/pagemap.h> +#include <linux/slab.h> +#include <linux/rbtree.h> +#include <linux/dma-mapping.h> /* for DMA_*_DEVICE */ + +#include "rds.h" + +/* + * XXX + * - build with sparse + * - should we detect duplicate keys on a socket? hmm. + * - an rdma is an mlock, apply rlimit? + */ + +/* + * get the number of pages by looking at the page indices that the start and + * end addresses fall in. + * + * Returns 0 if the vec is invalid. It is invalid if the number of bytes + * causes the address to wrap or overflows an unsigned int. This comes + * from being stored in the 'length' member of 'struct scatterlist'. + */ +static unsigned int rds_pages_in_vec(struct rds_iovec *vec) +{ + if ((vec->addr + vec->bytes <= vec->addr) || + (vec->bytes > (u64)UINT_MAX)) + return 0; + + return ((vec->addr + vec->bytes + PAGE_SIZE - 1) >> PAGE_SHIFT) - + (vec->addr >> PAGE_SHIFT); +} + +static struct rds_mr *rds_mr_tree_walk(struct rb_root *root, u64 key, + struct rds_mr *insert) +{ + struct rb_node **p = &root->rb_node; + struct rb_node *parent = NULL; + struct rds_mr *mr; + + while (*p) { + parent = *p; + mr = rb_entry(parent, struct rds_mr, r_rb_node); + + if (key < mr->r_key) + p = &(*p)->rb_left; + else if (key > mr->r_key) + p = &(*p)->rb_right; + else + return mr; + } + + if (insert) { + rb_link_node(&insert->r_rb_node, parent, p); + rb_insert_color(&insert->r_rb_node, root); + kref_get(&insert->r_kref); + } + return NULL; +} + +/* + * Destroy the transport-specific part of a MR. + */ +static void rds_destroy_mr(struct rds_mr *mr) +{ + struct rds_sock *rs = mr->r_sock; + void *trans_private = NULL; + unsigned long flags; + + rdsdebug("RDS: destroy mr key is %x refcnt %u\n", + mr->r_key, kref_read(&mr->r_kref)); + + spin_lock_irqsave(&rs->rs_rdma_lock, flags); + if (!RB_EMPTY_NODE(&mr->r_rb_node)) + rb_erase(&mr->r_rb_node, &rs->rs_rdma_keys); + trans_private = mr->r_trans_private; + mr->r_trans_private = NULL; + spin_unlock_irqrestore(&rs->rs_rdma_lock, flags); + + if (trans_private) + mr->r_trans->free_mr(trans_private, mr->r_invalidate); +} + +void __rds_put_mr_final(struct kref *kref) +{ + struct rds_mr *mr = container_of(kref, struct rds_mr, r_kref); + + rds_destroy_mr(mr); + kfree(mr); +} + +/* + * By the time this is called we can't have any more ioctls called on + * the socket so we don't need to worry about racing with others. + */ +void rds_rdma_drop_keys(struct rds_sock *rs) +{ + struct rds_mr *mr; + struct rb_node *node; + unsigned long flags; + + /* Release any MRs associated with this socket */ + spin_lock_irqsave(&rs->rs_rdma_lock, flags); + while ((node = rb_first(&rs->rs_rdma_keys))) { + mr = rb_entry(node, struct rds_mr, r_rb_node); + if (mr->r_trans == rs->rs_transport) + mr->r_invalidate = 0; + rb_erase(&mr->r_rb_node, &rs->rs_rdma_keys); + RB_CLEAR_NODE(&mr->r_rb_node); + spin_unlock_irqrestore(&rs->rs_rdma_lock, flags); + kref_put(&mr->r_kref, __rds_put_mr_final); + spin_lock_irqsave(&rs->rs_rdma_lock, flags); + } + spin_unlock_irqrestore(&rs->rs_rdma_lock, flags); + + if (rs->rs_transport && rs->rs_transport->flush_mrs) + rs->rs_transport->flush_mrs(); +} + +/* + * Helper function to pin user pages. + */ +static int rds_pin_pages(unsigned long user_addr, unsigned int nr_pages, + struct page **pages, int write) +{ + unsigned int gup_flags = FOLL_LONGTERM; + int ret; + + if (write) + gup_flags |= FOLL_WRITE; + + ret = pin_user_pages_fast(user_addr, nr_pages, gup_flags, pages); + if (ret >= 0 && ret < nr_pages) { + unpin_user_pages(pages, ret); + ret = -EFAULT; + } + + return ret; +} + +static int __rds_rdma_map(struct rds_sock *rs, struct rds_get_mr_args *args, + u64 *cookie_ret, struct rds_mr **mr_ret, + struct rds_conn_path *cp) +{ + struct rds_mr *mr = NULL, *found; + struct scatterlist *sg = NULL; + unsigned int nr_pages; + struct page **pages = NULL; + void *trans_private; + unsigned long flags; + rds_rdma_cookie_t cookie; + unsigned int nents = 0; + int need_odp = 0; + long i; + int ret; + + if (ipv6_addr_any(&rs->rs_bound_addr) || !rs->rs_transport) { + ret = -ENOTCONN; /* XXX not a great errno */ + goto out; + } + + if (!rs->rs_transport->get_mr) { + ret = -EOPNOTSUPP; + goto out; + } + + /* If the combination of the addr and size requested for this memory + * region causes an integer overflow, return error. + */ + if (((args->vec.addr + args->vec.bytes) < args->vec.addr) || + PAGE_ALIGN(args->vec.addr + args->vec.bytes) < + (args->vec.addr + args->vec.bytes)) { + ret = -EINVAL; + goto out; + } + + if (!can_do_mlock()) { + ret = -EPERM; + goto out; + } + + nr_pages = rds_pages_in_vec(&args->vec); + if (nr_pages == 0) { + ret = -EINVAL; + goto out; + } + + /* Restrict the size of mr irrespective of underlying transport + * To account for unaligned mr regions, subtract one from nr_pages + */ + if ((nr_pages - 1) > (RDS_MAX_MSG_SIZE >> PAGE_SHIFT)) { + ret = -EMSGSIZE; + goto out; + } + + rdsdebug("RDS: get_mr addr %llx len %llu nr_pages %u\n", + args->vec.addr, args->vec.bytes, nr_pages); + + /* XXX clamp nr_pages to limit the size of this alloc? */ + pages = kcalloc(nr_pages, sizeof(struct page *), GFP_KERNEL); + if (!pages) { + ret = -ENOMEM; + goto out; + } + + mr = kzalloc(sizeof(struct rds_mr), GFP_KERNEL); + if (!mr) { + ret = -ENOMEM; + goto out; + } + + kref_init(&mr->r_kref); + RB_CLEAR_NODE(&mr->r_rb_node); + mr->r_trans = rs->rs_transport; + mr->r_sock = rs; + + if (args->flags & RDS_RDMA_USE_ONCE) + mr->r_use_once = 1; + if (args->flags & RDS_RDMA_INVALIDATE) + mr->r_invalidate = 1; + if (args->flags & RDS_RDMA_READWRITE) + mr->r_write = 1; + + /* + * Pin the pages that make up the user buffer and transfer the page + * pointers to the mr's sg array. We check to see if we've mapped + * the whole region after transferring the partial page references + * to the sg array so that we can have one page ref cleanup path. + * + * For now we have no flag that tells us whether the mapping is + * r/o or r/w. We need to assume r/w, or we'll do a lot of RDMA to + * the zero page. + */ + ret = rds_pin_pages(args->vec.addr, nr_pages, pages, 1); + if (ret == -EOPNOTSUPP) { + need_odp = 1; + } else if (ret <= 0) { + goto out; + } else { + nents = ret; + sg = kmalloc_array(nents, sizeof(*sg), GFP_KERNEL); + if (!sg) { + ret = -ENOMEM; + goto out; + } + WARN_ON(!nents); + sg_init_table(sg, nents); + + /* Stick all pages into the scatterlist */ + for (i = 0 ; i < nents; i++) + sg_set_page(&sg[i], pages[i], PAGE_SIZE, 0); + + rdsdebug("RDS: trans_private nents is %u\n", nents); + } + /* Obtain a transport specific MR. If this succeeds, the + * s/g list is now owned by the MR. + * Note that dma_map() implies that pending writes are + * flushed to RAM, so no dma_sync is needed here. */ + trans_private = rs->rs_transport->get_mr( + sg, nents, rs, &mr->r_key, cp ? cp->cp_conn : NULL, + args->vec.addr, args->vec.bytes, + need_odp ? ODP_ZEROBASED : ODP_NOT_NEEDED); + + if (IS_ERR(trans_private)) { + /* In ODP case, we don't GUP pages, so don't need + * to release anything. + */ + if (!need_odp) { + unpin_user_pages(pages, nr_pages); + kfree(sg); + } + ret = PTR_ERR(trans_private); + goto out; + } + + mr->r_trans_private = trans_private; + + rdsdebug("RDS: get_mr put_user key is %x cookie_addr %p\n", + mr->r_key, (void *)(unsigned long) args->cookie_addr); + + /* The user may pass us an unaligned address, but we can only + * map page aligned regions. So we keep the offset, and build + * a 64bit cookie containing <R_Key, offset> and pass that + * around. */ + if (need_odp) + cookie = rds_rdma_make_cookie(mr->r_key, 0); + else + cookie = rds_rdma_make_cookie(mr->r_key, + args->vec.addr & ~PAGE_MASK); + if (cookie_ret) + *cookie_ret = cookie; + + if (args->cookie_addr && + put_user(cookie, (u64 __user *)(unsigned long)args->cookie_addr)) { + if (!need_odp) { + unpin_user_pages(pages, nr_pages); + kfree(sg); + } + ret = -EFAULT; + goto out; + } + + /* Inserting the new MR into the rbtree bumps its + * reference count. */ + spin_lock_irqsave(&rs->rs_rdma_lock, flags); + found = rds_mr_tree_walk(&rs->rs_rdma_keys, mr->r_key, mr); + spin_unlock_irqrestore(&rs->rs_rdma_lock, flags); + + BUG_ON(found && found != mr); + + rdsdebug("RDS: get_mr key is %x\n", mr->r_key); + if (mr_ret) { + kref_get(&mr->r_kref); + *mr_ret = mr; + } + + ret = 0; +out: + kfree(pages); + if (mr) + kref_put(&mr->r_kref, __rds_put_mr_final); + return ret; +} + +int rds_get_mr(struct rds_sock *rs, sockptr_t optval, int optlen) +{ + struct rds_get_mr_args args; + + if (optlen != sizeof(struct rds_get_mr_args)) + return -EINVAL; + + if (copy_from_sockptr(&args, optval, sizeof(struct rds_get_mr_args))) + return -EFAULT; + + return __rds_rdma_map(rs, &args, NULL, NULL, NULL); +} + +int rds_get_mr_for_dest(struct rds_sock *rs, sockptr_t optval, int optlen) +{ + struct rds_get_mr_for_dest_args args; + struct rds_get_mr_args new_args; + + if (optlen != sizeof(struct rds_get_mr_for_dest_args)) + return -EINVAL; + + if (copy_from_sockptr(&args, optval, + sizeof(struct rds_get_mr_for_dest_args))) + return -EFAULT; + + /* + * Initially, just behave like get_mr(). + * TODO: Implement get_mr as wrapper around this + * and deprecate it. + */ + new_args.vec = args.vec; + new_args.cookie_addr = args.cookie_addr; + new_args.flags = args.flags; + + return __rds_rdma_map(rs, &new_args, NULL, NULL, NULL); +} + +/* + * Free the MR indicated by the given R_Key + */ +int rds_free_mr(struct rds_sock *rs, sockptr_t optval, int optlen) +{ + struct rds_free_mr_args args; + struct rds_mr *mr; + unsigned long flags; + + if (optlen != sizeof(struct rds_free_mr_args)) + return -EINVAL; + + if (copy_from_sockptr(&args, optval, sizeof(struct rds_free_mr_args))) + return -EFAULT; + + /* Special case - a null cookie means flush all unused MRs */ + if (args.cookie == 0) { + if (!rs->rs_transport || !rs->rs_transport->flush_mrs) + return -EINVAL; + rs->rs_transport->flush_mrs(); + return 0; + } + + /* Look up the MR given its R_key and remove it from the rbtree + * so nobody else finds it. + * This should also prevent races with rds_rdma_unuse. + */ + spin_lock_irqsave(&rs->rs_rdma_lock, flags); + mr = rds_mr_tree_walk(&rs->rs_rdma_keys, rds_rdma_cookie_key(args.cookie), NULL); + if (mr) { + rb_erase(&mr->r_rb_node, &rs->rs_rdma_keys); + RB_CLEAR_NODE(&mr->r_rb_node); + if (args.flags & RDS_RDMA_INVALIDATE) + mr->r_invalidate = 1; + } + spin_unlock_irqrestore(&rs->rs_rdma_lock, flags); + + if (!mr) + return -EINVAL; + + kref_put(&mr->r_kref, __rds_put_mr_final); + return 0; +} + +/* + * This is called when we receive an extension header that + * tells us this MR was used. It allows us to implement + * use_once semantics + */ +void rds_rdma_unuse(struct rds_sock *rs, u32 r_key, int force) +{ + struct rds_mr *mr; + unsigned long flags; + int zot_me = 0; + + spin_lock_irqsave(&rs->rs_rdma_lock, flags); + mr = rds_mr_tree_walk(&rs->rs_rdma_keys, r_key, NULL); + if (!mr) { + pr_debug("rds: trying to unuse MR with unknown r_key %u!\n", + r_key); + spin_unlock_irqrestore(&rs->rs_rdma_lock, flags); + return; + } + + /* Get a reference so that the MR won't go away before calling + * sync_mr() below. + */ + kref_get(&mr->r_kref); + + /* If it is going to be freed, remove it from the tree now so + * that no other thread can find it and free it. + */ + if (mr->r_use_once || force) { + rb_erase(&mr->r_rb_node, &rs->rs_rdma_keys); + RB_CLEAR_NODE(&mr->r_rb_node); + zot_me = 1; + } + spin_unlock_irqrestore(&rs->rs_rdma_lock, flags); + + /* May have to issue a dma_sync on this memory region. + * Note we could avoid this if the operation was a RDMA READ, + * but at this point we can't tell. */ + if (mr->r_trans->sync_mr) + mr->r_trans->sync_mr(mr->r_trans_private, DMA_FROM_DEVICE); + + /* Release the reference held above. */ + kref_put(&mr->r_kref, __rds_put_mr_final); + + /* If the MR was marked as invalidate, this will + * trigger an async flush. */ + if (zot_me) + kref_put(&mr->r_kref, __rds_put_mr_final); +} + +void rds_rdma_free_op(struct rm_rdma_op *ro) +{ + unsigned int i; + + if (ro->op_odp_mr) { + kref_put(&ro->op_odp_mr->r_kref, __rds_put_mr_final); + } else { + for (i = 0; i < ro->op_nents; i++) { + struct page *page = sg_page(&ro->op_sg[i]); + + /* Mark page dirty if it was possibly modified, which + * is the case for a RDMA_READ which copies from remote + * to local memory + */ + unpin_user_pages_dirty_lock(&page, 1, !ro->op_write); + } + } + + kfree(ro->op_notifier); + ro->op_notifier = NULL; + ro->op_active = 0; + ro->op_odp_mr = NULL; +} + +void rds_atomic_free_op(struct rm_atomic_op *ao) +{ + struct page *page = sg_page(ao->op_sg); + + /* Mark page dirty if it was possibly modified, which + * is the case for a RDMA_READ which copies from remote + * to local memory */ + unpin_user_pages_dirty_lock(&page, 1, true); + + kfree(ao->op_notifier); + ao->op_notifier = NULL; + ao->op_active = 0; +} + + +/* + * Count the number of pages needed to describe an incoming iovec array. + */ +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_iov_vector *iov) +{ + struct rds_iovec *vec; + struct rds_iovec __user *local_vec; + int tot_pages = 0; + unsigned int nr_pages; + unsigned int i; + + local_vec = (struct rds_iovec __user *)(unsigned long) args->local_vec_addr; + + if (args->nr_local == 0) + return -EINVAL; + + if (args->nr_local > UIO_MAXIOV) + return -EMSGSIZE; + + iov->iov = kcalloc(args->nr_local, + sizeof(struct rds_iovec), + GFP_KERNEL); + if (!iov->iov) + return -ENOMEM; + + vec = &iov->iov[0]; + + if (copy_from_user(vec, local_vec, args->nr_local * + sizeof(struct rds_iovec))) + return -EFAULT; + iov->len = args->nr_local; + + /* figure out the number of pages in the vector */ + for (i = 0; i < args->nr_local; i++, vec++) { + + nr_pages = rds_pages_in_vec(vec); + 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 * sizeof(struct scatterlist); +} + +/* + * The application asks for a RDMA transfer. + * Extract all arguments and set up the rdma_op + */ +int rds_cmsg_rdma_args(struct rds_sock *rs, struct rds_message *rm, + struct cmsghdr *cmsg, + struct rds_iov_vector *vec) +{ + struct rds_rdma_args *args; + struct rm_rdma_op *op = &rm->rdma; + int nr_pages; + unsigned int nr_bytes; + struct page **pages = NULL; + struct rds_iovec *iovs; + unsigned int i, j; + int ret = 0; + bool odp_supported = true; + + if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct rds_rdma_args)) + || rm->rdma.op_active) + return -EINVAL; + + args = CMSG_DATA(cmsg); + + if (ipv6_addr_any(&rs->rs_bound_addr)) { + ret = -ENOTCONN; /* XXX not a great errno */ + goto out_ret; + } + + if (args->nr_local > UIO_MAXIOV) { + ret = -EMSGSIZE; + goto out_ret; + } + + if (vec->len != args->nr_local) { + ret = -EINVAL; + goto out_ret; + } + /* odp-mr is not supported for multiple requests within one message */ + if (args->nr_local != 1) + odp_supported = false; + + iovs = vec->iov; + + nr_pages = rds_rdma_pages(iovs, args->nr_local); + if (nr_pages < 0) { + ret = -EINVAL; + goto out_ret; + } + + pages = kcalloc(nr_pages, sizeof(struct page *), GFP_KERNEL); + if (!pages) { + ret = -ENOMEM; + goto out_ret; + } + + op->op_write = !!(args->flags & RDS_RDMA_READWRITE); + op->op_fence = !!(args->flags & RDS_RDMA_FENCE); + op->op_notify = !!(args->flags & RDS_RDMA_NOTIFY_ME); + op->op_silent = !!(args->flags & RDS_RDMA_SILENT); + op->op_active = 1; + op->op_recverr = rs->rs_recverr; + op->op_odp_mr = NULL; + + WARN_ON(!nr_pages); + op->op_sg = rds_message_alloc_sgs(rm, nr_pages); + if (IS_ERR(op->op_sg)) { + ret = PTR_ERR(op->op_sg); + goto out_pages; + } + + if (op->op_notify || op->op_recverr) { + /* We allocate an uninitialized notifier here, because + * we don't want to do that in the completion handler. We + * would have to use GFP_ATOMIC there, and don't want to deal + * with failed allocations. + */ + op->op_notifier = kmalloc(sizeof(struct rds_notifier), GFP_KERNEL); + if (!op->op_notifier) { + ret = -ENOMEM; + goto out_pages; + } + op->op_notifier->n_user_token = args->user_token; + op->op_notifier->n_status = RDS_RDMA_SUCCESS; + } + + /* The cookie contains the R_Key of the remote memory region, and + * optionally an offset into it. This is how we implement RDMA into + * unaligned memory. + * When setting up the RDMA, we need to add that offset to the + * destination address (which is really an offset into the MR) + * FIXME: We may want to move this into ib_rdma.c + */ + op->op_rkey = rds_rdma_cookie_key(args->cookie); + op->op_remote_addr = args->remote_vec.addr + rds_rdma_cookie_offset(args->cookie); + + nr_bytes = 0; + + rdsdebug("RDS: rdma prepare nr_local %llu rva %llx rkey %x\n", + (unsigned long long)args->nr_local, + (unsigned long long)args->remote_vec.addr, + op->op_rkey); + + for (i = 0; i < args->nr_local; i++) { + 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 = 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(iov->addr, nr, pages, !op->op_write); + if ((!odp_supported && ret <= 0) || + (odp_supported && ret <= 0 && ret != -EOPNOTSUPP)) + goto out_pages; + + if (ret == -EOPNOTSUPP) { + struct rds_mr *local_odp_mr; + + if (!rs->rs_transport->get_mr) { + ret = -EOPNOTSUPP; + goto out_pages; + } + local_odp_mr = + kzalloc(sizeof(*local_odp_mr), GFP_KERNEL); + if (!local_odp_mr) { + ret = -ENOMEM; + goto out_pages; + } + RB_CLEAR_NODE(&local_odp_mr->r_rb_node); + kref_init(&local_odp_mr->r_kref); + local_odp_mr->r_trans = rs->rs_transport; + local_odp_mr->r_sock = rs; + local_odp_mr->r_trans_private = + rs->rs_transport->get_mr( + NULL, 0, rs, &local_odp_mr->r_key, NULL, + iov->addr, iov->bytes, ODP_VIRTUAL); + if (IS_ERR(local_odp_mr->r_trans_private)) { + ret = IS_ERR(local_odp_mr->r_trans_private); + rdsdebug("get_mr ret %d %p\"", ret, + local_odp_mr->r_trans_private); + kfree(local_odp_mr); + ret = -EOPNOTSUPP; + goto out_pages; + } + rdsdebug("Need odp; local_odp_mr %p trans_private %p\n", + local_odp_mr, local_odp_mr->r_trans_private); + op->op_odp_mr = local_odp_mr; + op->op_odp_addr = iov->addr; + } + + rdsdebug("RDS: nr_bytes %u nr %u iov->bytes %llu iov->addr %llx\n", + nr_bytes, nr, iov->bytes, iov->addr); + + nr_bytes += iov->bytes; + + for (j = 0; j < nr; j++) { + 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, iov->bytes, PAGE_SIZE - offset), + offset); + + sg_dma_len(sg) = sg->length; + rdsdebug("RDS: sg->offset %x sg->len %x iov->addr %llx iov->bytes %llu\n", + sg->offset, sg->length, iov->addr, iov->bytes); + + iov->addr += sg->length; + iov->bytes -= sg->length; + } + + op->op_nents += nr; + } + + if (nr_bytes > args->remote_vec.bytes) { + rdsdebug("RDS nr_bytes %u remote_bytes %u do not match\n", + nr_bytes, + (unsigned int) args->remote_vec.bytes); + ret = -EINVAL; + goto out_pages; + } + op->op_bytes = nr_bytes; + ret = 0; + +out_pages: + kfree(pages); +out_ret: + if (ret) + rds_rdma_free_op(op); + else + rds_stats_inc(s_send_rdma); + + return ret; +} + +/* + * The application wants us to pass an RDMA destination (aka MR) + * to the remote + */ +int rds_cmsg_rdma_dest(struct rds_sock *rs, struct rds_message *rm, + struct cmsghdr *cmsg) +{ + unsigned long flags; + struct rds_mr *mr; + u32 r_key; + int err = 0; + + if (cmsg->cmsg_len < CMSG_LEN(sizeof(rds_rdma_cookie_t)) || + rm->m_rdma_cookie != 0) + return -EINVAL; + + memcpy(&rm->m_rdma_cookie, CMSG_DATA(cmsg), sizeof(rm->m_rdma_cookie)); + + /* We are reusing a previously mapped MR here. Most likely, the + * application has written to the buffer, so we need to explicitly + * flush those writes to RAM. Otherwise the HCA may not see them + * when doing a DMA from that buffer. + */ + r_key = rds_rdma_cookie_key(rm->m_rdma_cookie); + + spin_lock_irqsave(&rs->rs_rdma_lock, flags); + mr = rds_mr_tree_walk(&rs->rs_rdma_keys, r_key, NULL); + if (!mr) + err = -EINVAL; /* invalid r_key */ + else + kref_get(&mr->r_kref); + spin_unlock_irqrestore(&rs->rs_rdma_lock, flags); + + if (mr) { + mr->r_trans->sync_mr(mr->r_trans_private, + DMA_TO_DEVICE); + rm->rdma.op_rdma_mr = mr; + } + return err; +} + +/* + * The application passes us an address range it wants to enable RDMA + * to/from. We map the area, and save the <R_Key,offset> pair + * in rm->m_rdma_cookie. This causes it to be sent along to the peer + * in an extension header. + */ +int rds_cmsg_rdma_map(struct rds_sock *rs, struct rds_message *rm, + struct cmsghdr *cmsg) +{ + if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct rds_get_mr_args)) || + rm->m_rdma_cookie != 0) + return -EINVAL; + + return __rds_rdma_map(rs, CMSG_DATA(cmsg), &rm->m_rdma_cookie, + &rm->rdma.op_rdma_mr, rm->m_conn_path); +} + +/* + * Fill in rds_message for an atomic request. + */ +int rds_cmsg_atomic(struct rds_sock *rs, struct rds_message *rm, + struct cmsghdr *cmsg) +{ + struct page *page = NULL; + struct rds_atomic_args *args; + int ret = 0; + + if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct rds_atomic_args)) + || rm->atomic.op_active) + return -EINVAL; + + args = CMSG_DATA(cmsg); + + /* Nonmasked & masked cmsg ops converted to masked hw ops */ + switch (cmsg->cmsg_type) { + case RDS_CMSG_ATOMIC_FADD: + rm->atomic.op_type = RDS_ATOMIC_TYPE_FADD; + rm->atomic.op_m_fadd.add = args->fadd.add; + rm->atomic.op_m_fadd.nocarry_mask = 0; + break; + case RDS_CMSG_MASKED_ATOMIC_FADD: + rm->atomic.op_type = RDS_ATOMIC_TYPE_FADD; + rm->atomic.op_m_fadd.add = args->m_fadd.add; + rm->atomic.op_m_fadd.nocarry_mask = args->m_fadd.nocarry_mask; + break; + case RDS_CMSG_ATOMIC_CSWP: + rm->atomic.op_type = RDS_ATOMIC_TYPE_CSWP; + rm->atomic.op_m_cswp.compare = args->cswp.compare; + rm->atomic.op_m_cswp.swap = args->cswp.swap; + rm->atomic.op_m_cswp.compare_mask = ~0; + rm->atomic.op_m_cswp.swap_mask = ~0; + break; + case RDS_CMSG_MASKED_ATOMIC_CSWP: + rm->atomic.op_type = RDS_ATOMIC_TYPE_CSWP; + rm->atomic.op_m_cswp.compare = args->m_cswp.compare; + rm->atomic.op_m_cswp.swap = args->m_cswp.swap; + rm->atomic.op_m_cswp.compare_mask = args->m_cswp.compare_mask; + rm->atomic.op_m_cswp.swap_mask = args->m_cswp.swap_mask; + break; + default: + BUG(); /* should never happen */ + } + + rm->atomic.op_notify = !!(args->flags & RDS_RDMA_NOTIFY_ME); + rm->atomic.op_silent = !!(args->flags & RDS_RDMA_SILENT); + rm->atomic.op_active = 1; + rm->atomic.op_recverr = rs->rs_recverr; + rm->atomic.op_sg = rds_message_alloc_sgs(rm, 1); + if (IS_ERR(rm->atomic.op_sg)) { + ret = PTR_ERR(rm->atomic.op_sg); + goto err; + } + + /* verify 8 byte-aligned */ + if (args->local_addr & 0x7) { + ret = -EFAULT; + goto err; + } + + ret = rds_pin_pages(args->local_addr, 1, &page, 1); + if (ret != 1) + goto err; + ret = 0; + + sg_set_page(rm->atomic.op_sg, page, 8, offset_in_page(args->local_addr)); + + if (rm->atomic.op_notify || rm->atomic.op_recverr) { + /* We allocate an uninitialized notifier here, because + * we don't want to do that in the completion handler. We + * would have to use GFP_ATOMIC there, and don't want to deal + * with failed allocations. + */ + rm->atomic.op_notifier = kmalloc(sizeof(*rm->atomic.op_notifier), GFP_KERNEL); + if (!rm->atomic.op_notifier) { + ret = -ENOMEM; + goto err; + } + + rm->atomic.op_notifier->n_user_token = args->user_token; + rm->atomic.op_notifier->n_status = RDS_RDMA_SUCCESS; + } + + rm->atomic.op_rkey = rds_rdma_cookie_key(args->cookie); + rm->atomic.op_remote_addr = args->remote_addr + rds_rdma_cookie_offset(args->cookie); + + return ret; +err: + if (page) + unpin_user_page(page); + rm->atomic.op_active = 0; + kfree(rm->atomic.op_notifier); + + return ret; +} |