linux/net/rds/rdma.c
Andy Grover d139ff0907 RDS: Let rds_message_alloc_sgs() return NULL
Even with the previous fix, we still are reading the iovecs once
to determine SGs needed, and then again later on. Preallocating
space for sg lists as part of rds_message seemed like a good idea
but it might be better to not do this. While working to redo that
code, this patch attempts to protect against userspace rewriting
the rds_iovec array between the first and second accesses.

The consequences of this would be either a too-small or too-large
sg list array. Too large is not an issue. This patch changes all
callers of message_alloc_sgs to handle running out of preallocated
sgs, and fail gracefully.

Signed-off-by: Andy Grover <andy.grover@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-10-30 16:34:18 -07:00

859 lines
22 KiB
C

/*
* 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 "rds.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;
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 = container_of(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);
rds_destroy_mr(mr);
rds_mr_put(mr);
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)
{
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) {
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) {
ret = -ENOMEM;
goto out;
}
mr = kzalloc(sizeof(struct rds_mr), GFP_KERNEL);
if (!mr) {
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, nr_pages, pages, 1);
if (ret < 0)
goto out;
nents = ret;
sg = kcalloc(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);
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) {
printk(KERN_ERR "rds: trying to unuse MR with unknown r_key %u!\n", r_key);
spin_unlock_irqrestore(&rs->rs_rdma_lock, flags);
return;
}
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);
/* 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 rm_rdma_op *ro)
{
unsigned int i;
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 */
if (!ro->op_write) {
BUG_ON(irqs_disabled());
set_page_dirty(page);
}
put_page(page);
}
kfree(ro->op_notifier);
ro->op_notifier = NULL;
ro->op_active = 0;
}
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 */
set_page_dirty(page);
put_page(page);
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_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;
/* 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)))
return -EFAULT;
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_rdma_args *args;
struct rm_rdma_op *op = &rm->rdma;
int nr_pages;
unsigned int nr_bytes;
struct page **pages = NULL;
struct rds_iovec iovstack[UIO_FASTIOV], *iovs = iovstack;
int iov_size;
unsigned int i, j;
int ret = 0;
if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct rds_rdma_args))
|| rm->rdma.op_active)
return -EINVAL;
args = CMSG_DATA(cmsg);
if (rs->rs_bound_addr == 0) {
ret = -ENOTCONN; /* XXX not a great errno */
goto out;
}
if (args->nr_local > (u64)UINT_MAX) {
ret = -EMSGSIZE;
goto out;
}
/* 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;
}
pages = kcalloc(nr_pages, sizeof(struct page *), GFP_KERNEL);
if (!pages) {
ret = -ENOMEM;
goto out;
}
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;
WARN_ON(!nr_pages);
op->op_sg = rds_message_alloc_sgs(rm, nr_pages);
if (!op->op_sg) {
ret = -ENOMEM;
goto out;
}
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;
}
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 (ret < 0)
goto out;
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);
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;
}
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);
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
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->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);
}
/*
* 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 (!rm->atomic.op_sg) {
ret = -ENOMEM;
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)
put_page(page);
kfree(rm->atomic.op_notifier);
return ret;
}