RDS: RDMA support
Some transports may support RDMA features. This handles the non-transport-specific parts, like pinning user pages and tracking mapped regions. Signed-off-by: Andy Grover <andy.grover@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Andy Grover
David S. Miller
parent
bdbe6fbc6a
commit
eff5f53bef
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@ -0,0 +1,679 @@
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/*
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* Copyright (c) 2007 Oracle. All rights reserved.
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*
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* This software is available to you under a choice of one of two
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* licenses. You may choose to be licensed under the terms of the GNU
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* General Public License (GPL) Version 2, available from the file
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* COPYING in the main directory of this source tree, or the
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* OpenIB.org BSD license below:
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*
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* Redistribution and use in source and binary forms, with or
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* without modification, are permitted provided that the following
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* conditions are met:
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*
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* - Redistributions of source code must retain the above
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* copyright notice, this list of conditions and the following
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* disclaimer.
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*
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* - Redistributions in binary form must reproduce the above
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* copyright notice, this list of conditions and the following
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* disclaimer in the documentation and/or other materials
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* provided with the distribution.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
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* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
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* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
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* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
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* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
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* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
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* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
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* SOFTWARE.
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*
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*/
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#include <linux/pagemap.h>
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#include <linux/rbtree.h>
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#include <linux/dma-mapping.h> /* for DMA_*_DEVICE */
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#include "rdma.h"
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/*
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* XXX
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* - build with sparse
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* - should we limit the size of a mr region? let transport return failure?
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* - should we detect duplicate keys on a socket? hmm.
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* - an rdma is an mlock, apply rlimit?
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*/
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/*
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* get the number of pages by looking at the page indices that the start and
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* end addresses fall in.
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*
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* Returns 0 if the vec is invalid. It is invalid if the number of bytes
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* causes the address to wrap or overflows an unsigned int. This comes
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* from being stored in the 'length' member of 'struct scatterlist'.
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*/
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static unsigned int rds_pages_in_vec(struct rds_iovec *vec)
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{
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if ((vec->addr + vec->bytes <= vec->addr) ||
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(vec->bytes > (u64)UINT_MAX))
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return 0;
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return ((vec->addr + vec->bytes + PAGE_SIZE - 1) >> PAGE_SHIFT) -
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(vec->addr >> PAGE_SHIFT);
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}
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static struct rds_mr *rds_mr_tree_walk(struct rb_root *root, u64 key,
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struct rds_mr *insert)
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{
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struct rb_node **p = &root->rb_node;
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struct rb_node *parent = NULL;
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struct rds_mr *mr;
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while (*p) {
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parent = *p;
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mr = rb_entry(parent, struct rds_mr, r_rb_node);
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if (key < mr->r_key)
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p = &(*p)->rb_left;
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else if (key > mr->r_key)
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p = &(*p)->rb_right;
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else
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return mr;
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}
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if (insert) {
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rb_link_node(&insert->r_rb_node, parent, p);
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rb_insert_color(&insert->r_rb_node, root);
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atomic_inc(&insert->r_refcount);
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}
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return NULL;
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}
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/*
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* Destroy the transport-specific part of a MR.
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*/
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static void rds_destroy_mr(struct rds_mr *mr)
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{
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struct rds_sock *rs = mr->r_sock;
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void *trans_private = NULL;
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unsigned long flags;
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rdsdebug("RDS: destroy mr key is %x refcnt %u\n",
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mr->r_key, atomic_read(&mr->r_refcount));
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if (test_and_set_bit(RDS_MR_DEAD, &mr->r_state))
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return;
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spin_lock_irqsave(&rs->rs_rdma_lock, flags);
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if (!RB_EMPTY_NODE(&mr->r_rb_node))
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rb_erase(&mr->r_rb_node, &rs->rs_rdma_keys);
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trans_private = mr->r_trans_private;
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mr->r_trans_private = NULL;
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spin_unlock_irqrestore(&rs->rs_rdma_lock, flags);
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if (trans_private)
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mr->r_trans->free_mr(trans_private, mr->r_invalidate);
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}
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void __rds_put_mr_final(struct rds_mr *mr)
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{
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rds_destroy_mr(mr);
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kfree(mr);
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}
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/*
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* By the time this is called we can't have any more ioctls called on
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* the socket so we don't need to worry about racing with others.
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*/
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void rds_rdma_drop_keys(struct rds_sock *rs)
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{
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struct rds_mr *mr;
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struct rb_node *node;
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/* Release any MRs associated with this socket */
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while ((node = rb_first(&rs->rs_rdma_keys))) {
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mr = container_of(node, struct rds_mr, r_rb_node);
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if (mr->r_trans == rs->rs_transport)
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mr->r_invalidate = 0;
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rds_mr_put(mr);
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}
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if (rs->rs_transport && rs->rs_transport->flush_mrs)
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rs->rs_transport->flush_mrs();
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}
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/*
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* Helper function to pin user pages.
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*/
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static int rds_pin_pages(unsigned long user_addr, unsigned int nr_pages,
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struct page **pages, int write)
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{
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int ret;
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down_read(¤t->mm->mmap_sem);
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ret = get_user_pages(current, current->mm, user_addr,
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nr_pages, write, 0, pages, NULL);
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up_read(¤t->mm->mmap_sem);
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if (0 <= ret && (unsigned) ret < nr_pages) {
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while (ret--)
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put_page(pages[ret]);
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ret = -EFAULT;
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}
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return ret;
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}
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static int __rds_rdma_map(struct rds_sock *rs, struct rds_get_mr_args *args,
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u64 *cookie_ret, struct rds_mr **mr_ret)
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{
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struct rds_mr *mr = NULL, *found;
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unsigned int nr_pages;
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struct page **pages = NULL;
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struct scatterlist *sg;
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void *trans_private;
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unsigned long flags;
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rds_rdma_cookie_t cookie;
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unsigned int nents;
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long i;
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int ret;
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if (rs->rs_bound_addr == 0) {
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ret = -ENOTCONN; /* XXX not a great errno */
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goto out;
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}
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if (rs->rs_transport->get_mr == NULL) {
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ret = -EOPNOTSUPP;
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goto out;
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}
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nr_pages = rds_pages_in_vec(&args->vec);
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if (nr_pages == 0) {
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ret = -EINVAL;
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goto out;
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}
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rdsdebug("RDS: get_mr addr %llx len %llu nr_pages %u\n",
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args->vec.addr, args->vec.bytes, nr_pages);
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/* XXX clamp nr_pages to limit the size of this alloc? */
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pages = kcalloc(nr_pages, sizeof(struct page *), GFP_KERNEL);
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if (pages == NULL) {
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ret = -ENOMEM;
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goto out;
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}
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mr = kzalloc(sizeof(struct rds_mr), GFP_KERNEL);
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if (mr == NULL) {
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ret = -ENOMEM;
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goto out;
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}
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atomic_set(&mr->r_refcount, 1);
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RB_CLEAR_NODE(&mr->r_rb_node);
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mr->r_trans = rs->rs_transport;
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mr->r_sock = rs;
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if (args->flags & RDS_RDMA_USE_ONCE)
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mr->r_use_once = 1;
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if (args->flags & RDS_RDMA_INVALIDATE)
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mr->r_invalidate = 1;
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if (args->flags & RDS_RDMA_READWRITE)
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mr->r_write = 1;
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/*
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* Pin the pages that make up the user buffer and transfer the page
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* pointers to the mr's sg array. We check to see if we've mapped
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* the whole region after transferring the partial page references
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* to the sg array so that we can have one page ref cleanup path.
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*
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* For now we have no flag that tells us whether the mapping is
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* r/o or r/w. We need to assume r/w, or we'll do a lot of RDMA to
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* the zero page.
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*/
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ret = rds_pin_pages(args->vec.addr & PAGE_MASK, nr_pages, pages, 1);
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if (ret < 0)
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goto out;
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nents = ret;
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sg = kcalloc(nents, sizeof(*sg), GFP_KERNEL);
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if (sg == NULL) {
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ret = -ENOMEM;
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goto out;
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}
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WARN_ON(!nents);
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sg_init_table(sg, nents);
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/* Stick all pages into the scatterlist */
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for (i = 0 ; i < nents; i++)
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sg_set_page(&sg[i], pages[i], PAGE_SIZE, 0);
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rdsdebug("RDS: trans_private nents is %u\n", nents);
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/* Obtain a transport specific MR. If this succeeds, the
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* s/g list is now owned by the MR.
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* Note that dma_map() implies that pending writes are
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* flushed to RAM, so no dma_sync is needed here. */
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trans_private = rs->rs_transport->get_mr(sg, nents, rs,
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&mr->r_key);
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if (IS_ERR(trans_private)) {
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for (i = 0 ; i < nents; i++)
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put_page(sg_page(&sg[i]));
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kfree(sg);
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ret = PTR_ERR(trans_private);
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goto out;
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}
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mr->r_trans_private = trans_private;
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rdsdebug("RDS: get_mr put_user key is %x cookie_addr %p\n",
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mr->r_key, (void *)(unsigned long) args->cookie_addr);
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/* The user may pass us an unaligned address, but we can only
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* map page aligned regions. So we keep the offset, and build
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* a 64bit cookie containing <R_Key, offset> and pass that
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* around. */
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cookie = rds_rdma_make_cookie(mr->r_key, args->vec.addr & ~PAGE_MASK);
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if (cookie_ret)
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*cookie_ret = cookie;
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if (args->cookie_addr && put_user(cookie, (u64 __user *)(unsigned long) args->cookie_addr)) {
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ret = -EFAULT;
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goto out;
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}
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/* Inserting the new MR into the rbtree bumps its
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* reference count. */
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spin_lock_irqsave(&rs->rs_rdma_lock, flags);
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found = rds_mr_tree_walk(&rs->rs_rdma_keys, mr->r_key, mr);
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spin_unlock_irqrestore(&rs->rs_rdma_lock, flags);
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BUG_ON(found && found != mr);
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rdsdebug("RDS: get_mr key is %x\n", mr->r_key);
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if (mr_ret) {
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atomic_inc(&mr->r_refcount);
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*mr_ret = mr;
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}
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ret = 0;
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out:
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kfree(pages);
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if (mr)
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rds_mr_put(mr);
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return ret;
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}
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int rds_get_mr(struct rds_sock *rs, char __user *optval, int optlen)
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{
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struct rds_get_mr_args args;
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if (optlen != sizeof(struct rds_get_mr_args))
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return -EINVAL;
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if (copy_from_user(&args, (struct rds_get_mr_args __user *)optval,
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sizeof(struct rds_get_mr_args)))
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return -EFAULT;
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return __rds_rdma_map(rs, &args, NULL, NULL);
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}
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/*
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* Free the MR indicated by the given R_Key
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*/
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int rds_free_mr(struct rds_sock *rs, char __user *optval, int optlen)
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{
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struct rds_free_mr_args args;
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struct rds_mr *mr;
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unsigned long flags;
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if (optlen != sizeof(struct rds_free_mr_args))
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return -EINVAL;
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if (copy_from_user(&args, (struct rds_free_mr_args __user *)optval,
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sizeof(struct rds_free_mr_args)))
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return -EFAULT;
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/* Special case - a null cookie means flush all unused MRs */
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if (args.cookie == 0) {
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if (!rs->rs_transport || !rs->rs_transport->flush_mrs)
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return -EINVAL;
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rs->rs_transport->flush_mrs();
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return 0;
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}
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/* Look up the MR given its R_key and remove it from the rbtree
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* so nobody else finds it.
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* This should also prevent races with rds_rdma_unuse.
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*/
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spin_lock_irqsave(&rs->rs_rdma_lock, flags);
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mr = rds_mr_tree_walk(&rs->rs_rdma_keys, rds_rdma_cookie_key(args.cookie), NULL);
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if (mr) {
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rb_erase(&mr->r_rb_node, &rs->rs_rdma_keys);
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RB_CLEAR_NODE(&mr->r_rb_node);
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if (args.flags & RDS_RDMA_INVALIDATE)
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mr->r_invalidate = 1;
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}
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spin_unlock_irqrestore(&rs->rs_rdma_lock, flags);
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if (!mr)
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return -EINVAL;
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/*
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* call rds_destroy_mr() ourselves so that we're sure it's done by the time
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* we return. If we let rds_mr_put() do it it might not happen until
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* someone else drops their ref.
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*/
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rds_destroy_mr(mr);
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rds_mr_put(mr);
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return 0;
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}
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/*
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* This is called when we receive an extension header that
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* tells us this MR was used. It allows us to implement
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* use_once semantics
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*/
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void rds_rdma_unuse(struct rds_sock *rs, u32 r_key, int force)
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{
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struct rds_mr *mr;
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unsigned long flags;
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int zot_me = 0;
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spin_lock_irqsave(&rs->rs_rdma_lock, flags);
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mr = rds_mr_tree_walk(&rs->rs_rdma_keys, r_key, NULL);
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if (mr && (mr->r_use_once || force)) {
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rb_erase(&mr->r_rb_node, &rs->rs_rdma_keys);
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RB_CLEAR_NODE(&mr->r_rb_node);
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zot_me = 1;
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} else if (mr)
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atomic_inc(&mr->r_refcount);
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spin_unlock_irqrestore(&rs->rs_rdma_lock, flags);
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/* May have to issue a dma_sync on this memory region.
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* Note we could avoid this if the operation was a RDMA READ,
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* but at this point we can't tell. */
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if (mr != NULL) {
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if (mr->r_trans->sync_mr)
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mr->r_trans->sync_mr(mr->r_trans_private, DMA_FROM_DEVICE);
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/* If the MR was marked as invalidate, this will
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* trigger an async flush. */
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if (zot_me)
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rds_destroy_mr(mr);
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rds_mr_put(mr);
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}
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}
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void rds_rdma_free_op(struct rds_rdma_op *ro)
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{
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unsigned int i;
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for (i = 0; i < ro->r_nents; i++) {
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struct page *page = sg_page(&ro->r_sg[i]);
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/* Mark page dirty if it was possibly modified, which
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* is the case for a RDMA_READ which copies from remote
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* to local memory */
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if (!ro->r_write)
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set_page_dirty(page);
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put_page(page);
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}
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kfree(ro->r_notifier);
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kfree(ro);
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}
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/*
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* args is a pointer to an in-kernel copy in the sendmsg cmsg.
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*/
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static struct rds_rdma_op *rds_rdma_prepare(struct rds_sock *rs,
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struct rds_rdma_args *args)
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{
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struct rds_iovec vec;
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struct rds_rdma_op *op = NULL;
|
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unsigned int nr_pages;
|
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unsigned int max_pages;
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unsigned int nr_bytes;
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struct page **pages = NULL;
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struct rds_iovec __user *local_vec;
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struct scatterlist *sg;
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unsigned int nr;
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unsigned int i, j;
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int ret;
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|
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|
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if (rs->rs_bound_addr == 0) {
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ret = -ENOTCONN; /* XXX not a great errno */
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goto out;
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}
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||||
|
||||
if (args->nr_local > (u64)UINT_MAX) {
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ret = -EMSGSIZE;
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goto out;
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}
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nr_pages = 0;
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max_pages = 0;
|
||||
|
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local_vec = (struct rds_iovec __user *)(unsigned long) args->local_vec_addr;
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|
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/* figure out the number of pages in the vector */
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for (i = 0; i < args->nr_local; i++) {
|
||||
if (copy_from_user(&vec, &local_vec[i],
|
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sizeof(struct rds_iovec))) {
|
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ret = -EFAULT;
|
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goto out;
|
||||
}
|
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|
||||
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);
|
||||
}
|
||||
|
|
@ -0,0 +1,84 @@
|
|||
#ifndef _RDS_RDMA_H
|
||||
#define _RDS_RDMA_H
|
||||
|
||||
#include <linux/rbtree.h>
|
||||
#include <linux/spinlock.h>
|
||||
#include <linux/scatterlist.h>
|
||||
|
||||
#include "rds.h"
|
||||
|
||||
struct rds_mr {
|
||||
struct rb_node r_rb_node;
|
||||
atomic_t r_refcount;
|
||||
u32 r_key;
|
||||
|
||||
/* A copy of the creation flags */
|
||||
unsigned int r_use_once:1;
|
||||
unsigned int r_invalidate:1;
|
||||
unsigned int r_write:1;
|
||||
|
||||
/* This is for RDS_MR_DEAD.
|
||||
* It would be nice & consistent to make this part of the above
|
||||
* bit field here, but we need to use test_and_set_bit.
|
||||
*/
|
||||
unsigned long r_state;
|
||||
struct rds_sock *r_sock; /* back pointer to the socket that owns us */
|
||||
struct rds_transport *r_trans;
|
||||
void *r_trans_private;
|
||||
};
|
||||
|
||||
/* Flags for mr->r_state */
|
||||
#define RDS_MR_DEAD 0
|
||||
|
||||
struct rds_rdma_op {
|
||||
u32 r_key;
|
||||
u64 r_remote_addr;
|
||||
unsigned int r_write:1;
|
||||
unsigned int r_fence:1;
|
||||
unsigned int r_notify:1;
|
||||
unsigned int r_recverr:1;
|
||||
unsigned int r_mapped:1;
|
||||
struct rds_notifier *r_notifier;
|
||||
unsigned int r_bytes;
|
||||
unsigned int r_nents;
|
||||
unsigned int r_count;
|
||||
struct scatterlist r_sg[0];
|
||||
};
|
||||
|
||||
static inline rds_rdma_cookie_t rds_rdma_make_cookie(u32 r_key, u32 offset)
|
||||
{
|
||||
return r_key | (((u64) offset) << 32);
|
||||
}
|
||||
|
||||
static inline u32 rds_rdma_cookie_key(rds_rdma_cookie_t cookie)
|
||||
{
|
||||
return cookie;
|
||||
}
|
||||
|
||||
static inline u32 rds_rdma_cookie_offset(rds_rdma_cookie_t cookie)
|
||||
{
|
||||
return cookie >> 32;
|
||||
}
|
||||
|
||||
int rds_get_mr(struct rds_sock *rs, char __user *optval, int optlen);
|
||||
int rds_free_mr(struct rds_sock *rs, char __user *optval, int optlen);
|
||||
void rds_rdma_drop_keys(struct rds_sock *rs);
|
||||
int rds_cmsg_rdma_args(struct rds_sock *rs, struct rds_message *rm,
|
||||
struct cmsghdr *cmsg);
|
||||
int rds_cmsg_rdma_dest(struct rds_sock *rs, struct rds_message *rm,
|
||||
struct cmsghdr *cmsg);
|
||||
int rds_cmsg_rdma_args(struct rds_sock *rs, struct rds_message *rm,
|
||||
struct cmsghdr *cmsg);
|
||||
int rds_cmsg_rdma_map(struct rds_sock *rs, struct rds_message *rm,
|
||||
struct cmsghdr *cmsg);
|
||||
void rds_rdma_free_op(struct rds_rdma_op *ro);
|
||||
void rds_rdma_send_complete(struct rds_message *rm, int);
|
||||
|
||||
extern void __rds_put_mr_final(struct rds_mr *mr);
|
||||
static inline void rds_mr_put(struct rds_mr *mr)
|
||||
{
|
||||
if (atomic_dec_and_test(&mr->r_refcount))
|
||||
__rds_put_mr_final(mr);
|
||||
}
|
||||
|
||||
#endif
|
||||
Loading…
Reference in New Issue