| /* |
| * Copyright (c) 2007 Oracle. All rights reserved. |
| * |
| * 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 "rdma.h" |
| |
| /* |
| * XXX |
| * - build with sparse |
| * - should we limit the size of a mr region? let transport return failure? |
| * - 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); |
| atomic_inc(&insert->r_refcount); |
| } |
| 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, atomic_read(&mr->r_refcount)); |
| |
| if (test_and_set_bit(RDS_MR_DEAD, &mr->r_state)) |
| return; |
| |
| 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 rds_mr *mr) |
| { |
| 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; |
| |
| /* Release any MRs associated with this socket */ |
| while ((node = rb_first(&rs->rs_rdma_keys))) { |
| mr = container_of(node, struct rds_mr, r_rb_node); |
| if (mr->r_trans == rs->rs_transport) |
| mr->r_invalidate = 0; |
| rds_mr_put(mr); |
| } |
| |
| 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) |
| { |
| int ret; |
| |
| ret = get_user_pages_fast(user_addr, nr_pages, write, pages); |
| |
| if (ret >= 0 && ret < nr_pages) { |
| while (ret--) |
| put_page(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_mr *mr = NULL, *found; |
| unsigned int nr_pages; |
| struct page **pages = NULL; |
| struct scatterlist *sg; |
| void *trans_private; |
| unsigned long flags; |
| rds_rdma_cookie_t cookie; |
| unsigned int nents; |
| long i; |
| int ret; |
| |
| if (rs->rs_bound_addr == 0) { |
| ret = -ENOTCONN; /* XXX not a great errno */ |
| goto out; |
| } |
| |
| if (rs->rs_transport->get_mr == NULL) { |
| ret = -EOPNOTSUPP; |
| goto out; |
| } |
| |
| nr_pages = rds_pages_in_vec(&args->vec); |
| if (nr_pages == 0) { |
| ret = -EINVAL; |
| 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 == NULL) { |
| ret = -ENOMEM; |
| goto out; |
| } |
| |
| mr = kzalloc(sizeof(struct rds_mr), GFP_KERNEL); |
| if (mr == NULL) { |
| ret = -ENOMEM; |
| goto out; |
| } |
| |
| atomic_set(&mr->r_refcount, 1); |
| 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 & PAGE_MASK, nr_pages, pages, 1); |
| if (ret < 0) |
| goto out; |
| |
| nents = ret; |
| sg = kcalloc(nents, sizeof(*sg), GFP_KERNEL); |
| if (sg == NULL) { |
| 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); |
| |
| if (IS_ERR(trans_private)) { |
| for (i = 0 ; i < nents; i++) |
| put_page(sg_page(&sg[i])); |
| 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. */ |
| 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)) { |
| 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) { |
| atomic_inc(&mr->r_refcount); |
| *mr_ret = mr; |
| } |
| |
| ret = 0; |
| out: |
| kfree(pages); |
| if (mr) |
| rds_mr_put(mr); |
| return ret; |
| } |
| |
| int rds_get_mr(struct rds_sock *rs, char __user *optval, int optlen) |
| { |
| struct rds_get_mr_args args; |
| |
| if (optlen != sizeof(struct rds_get_mr_args)) |
| return -EINVAL; |
| |
| if (copy_from_user(&args, (struct rds_get_mr_args __user *)optval, |
| sizeof(struct rds_get_mr_args))) |
| return -EFAULT; |
| |
| return __rds_rdma_map(rs, &args, NULL, NULL); |
| } |
| |
| int rds_get_mr_for_dest(struct rds_sock *rs, char __user *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_user(&args, (struct rds_get_mr_for_dest_args __user *)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); |
| } |
| |
| /* |
| * Free the MR indicated by the given R_Key |
| */ |
| int rds_free_mr(struct rds_sock *rs, char __user *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_user(&args, (struct rds_free_mr_args __user *)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; |
| |
| /* |
| * call rds_destroy_mr() ourselves so that we're sure it's done by the time |
| * we return. If we let rds_mr_put() do it it might not happen until |
| * someone else drops their ref. |
| */ |
| rds_destroy_mr(mr); |
| rds_mr_put(mr); |
| 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 && (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; |
| } else if (mr) |
| atomic_inc(&mr->r_refcount); |
| 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 != NULL) { |
| if (mr->r_trans->sync_mr) |
| mr->r_trans->sync_mr(mr->r_trans_private, DMA_FROM_DEVICE); |
| |
| /* If the MR was marked as invalidate, this will |
| * trigger an async flush. */ |
| if (zot_me) |
| rds_destroy_mr(mr); |
| rds_mr_put(mr); |
| } |
| } |
| |
| void rds_rdma_free_op(struct rds_rdma_op *ro) |
| { |
| unsigned int i; |
| |
| for (i = 0; i < ro->r_nents; i++) { |
| struct page *page = sg_page(&ro->r_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 */ |
| if (!ro->r_write) { |
| BUG_ON(in_interrupt()); |
| set_page_dirty(page); |
| } |
| put_page(page); |
| } |
| |
| kfree(ro->r_notifier); |
| kfree(ro); |
| } |
| |
| /* |
| * args is a pointer to an in-kernel copy in the sendmsg cmsg. |
| */ |
| static struct rds_rdma_op *rds_rdma_prepare(struct rds_sock *rs, |
| struct rds_rdma_args *args) |
| { |
| struct rds_iovec vec; |
| struct rds_rdma_op *op = NULL; |
| unsigned int nr_pages; |
| unsigned int max_pages; |
| unsigned int nr_bytes; |
| struct page **pages = NULL; |
| struct rds_iovec __user *local_vec; |
| struct scatterlist *sg; |
| unsigned int nr; |
| unsigned int i, j; |
| int ret; |
| |
| |
| if (rs->rs_bound_addr == 0) { |
| ret = -ENOTCONN; /* XXX not a great errno */ |
| goto out; |
| } |
| |
| if (args->nr_local > UIO_MAXIOV) { |
| ret = -EMSGSIZE; |
| goto out; |
| } |
| |
| nr_pages = 0; |
| max_pages = 0; |
| |
| local_vec = (struct rds_iovec __user *)(unsigned long) args->local_vec_addr; |
| |
| /* figure out the number of pages in the vector */ |
| 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; |
| } |
| |
| max_pages = max(nr, max_pages); |
| nr_pages += nr; |
| } |
| |
| pages = kcalloc(max_pages, sizeof(struct page *), GFP_KERNEL); |
| if (pages == NULL) { |
| ret = -ENOMEM; |
| goto out; |
| } |
| |
| op = kzalloc(offsetof(struct rds_rdma_op, r_sg[nr_pages]), GFP_KERNEL); |
| if (op == NULL) { |
| ret = -ENOMEM; |
| goto out; |
| } |
| |
| op->r_write = !!(args->flags & RDS_RDMA_READWRITE); |
| op->r_fence = !!(args->flags & RDS_RDMA_FENCE); |
| op->r_notify = !!(args->flags & RDS_RDMA_NOTIFY_ME); |
| op->r_recverr = rs->rs_recverr; |
| WARN_ON(!nr_pages); |
| sg_init_table(op->r_sg, nr_pages); |
| |
| if (op->r_notify || op->r_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->r_notifier = kmalloc(sizeof(struct rds_notifier), GFP_KERNEL); |
| if (!op->r_notifier) { |
| ret = -ENOMEM; |
| goto out; |
| } |
| op->r_notifier->n_user_token = args->user_token; |
| op->r_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->r_key = rds_rdma_cookie_key(args->cookie); |
| op->r_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->r_key); |
| |
| 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; |
| } |
| |
| rs->rs_user_addr = vec.addr; |
| rs->rs_user_bytes = vec.bytes; |
| |
| /* did the user change the vec under us? */ |
| if (nr > max_pages || op->r_nents + nr > nr_pages) { |
| ret = -EINVAL; |
| goto out; |
| } |
| /* 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 & PAGE_MASK, nr, pages, !op->r_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); |
| |
| nr_bytes += vec.bytes; |
| |
| for (j = 0; j < nr; j++) { |
| unsigned int offset = vec.addr & ~PAGE_MASK; |
| |
| sg = &op->r_sg[op->r_nents + j]; |
| sg_set_page(sg, pages[j], |
| min_t(unsigned int, vec.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); |
| |
| vec.addr += sg->length; |
| vec.bytes -= sg->length; |
| } |
| |
| op->r_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; |
| } |
| op->r_bytes = nr_bytes; |
| |
| ret = 0; |
| out: |
| kfree(pages); |
| if (ret) { |
| if (op) |
| rds_rdma_free_op(op); |
| op = ERR_PTR(ret); |
| } |
| return op; |
| } |
| |
| /* |
| * 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_rdma_op *op; |
| |
| if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct rds_rdma_args)) || |
| rm->m_rdma_op != NULL) |
| return -EINVAL; |
| |
| op = rds_rdma_prepare(rs, CMSG_DATA(cmsg)); |
| if (IS_ERR(op)) |
| return PTR_ERR(op); |
| rds_stats_inc(s_send_rdma); |
| rm->m_rdma_op = op; |
| return 0; |
| } |
| |
| /* |
| * 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 == NULL) |
| err = -EINVAL; /* invalid r_key */ |
| else |
| atomic_inc(&mr->r_refcount); |
| spin_unlock_irqrestore(&rs->rs_rdma_lock, flags); |
| |
| if (mr) { |
| mr->r_trans->sync_mr(mr->r_trans_private, DMA_TO_DEVICE); |
| rm->m_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->m_rdma_mr); |
| } |