/*
* Copyright (c) 2016 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 "ib_mr.h"
struct rds_ib_mr *rds_ib_alloc_fmr(struct rds_ib_device *rds_ibdev, int npages)
{
struct rds_ib_mr_pool *pool;
struct rds_ib_mr *ibmr = NULL;
struct rds_ib_fmr *fmr;
int err = 0;
if (npages <= RDS_MR_8K_MSG_SIZE)
pool = rds_ibdev->mr_8k_pool;
else
pool = rds_ibdev->mr_1m_pool;
ibmr = rds_ib_try_reuse_ibmr(pool);
if (ibmr)
return ibmr;
ibmr = kzalloc_node(sizeof(*ibmr), GFP_KERNEL,
rdsibdev_to_node(rds_ibdev));
if (!ibmr) {
err = -ENOMEM;
goto out_no_cigar;
}
fmr = &ibmr->u.fmr;
fmr->fmr = ib_alloc_fmr(rds_ibdev->pd,
(IB_ACCESS_LOCAL_WRITE |
IB_ACCESS_REMOTE_READ |
IB_ACCESS_REMOTE_WRITE |
IB_ACCESS_REMOTE_ATOMIC),
&pool->fmr_attr);
if (IS_ERR(fmr->fmr)) {
err = PTR_ERR(fmr->fmr);
fmr->fmr = NULL;
pr_warn("RDS/IB: %s failed (err=%d)\n", __func__, err);
goto out_no_cigar;
}
ibmr->pool = pool;
if (pool->pool_type == RDS_IB_MR_8K_POOL)
rds_ib_stats_inc(s_ib_rdma_mr_8k_alloc);
else
rds_ib_stats_inc(s_ib_rdma_mr_1m_alloc);
return ibmr;
out_no_cigar:
if (ibmr) {
if (fmr->fmr)
ib_dealloc_fmr(fmr->fmr);
kfree(ibmr);
}
atomic_dec(&pool->item_count);
return ERR_PTR(err);
}
int rds_ib_map_fmr(struct rds_ib_device *rds_ibdev, struct rds_ib_mr *ibmr,
struct scatterlist *sg, unsigned int nents)
{
struct ib_device *dev = rds_ibdev->dev;
struct rds_ib_fmr *fmr = &ibmr->u.fmr;
struct scatterlist *scat = sg;
u64 io_addr = 0;
u64 *dma_pages;
u32 len;
int page_cnt, sg_dma_len;
int i, j;
int ret;
sg_dma_len = ib_dma_map_sg(dev, sg, nents, DMA_BIDIRECTIONAL);
if (unlikely(!sg_dma_len)) {
pr_warn("RDS/IB: %s failed!\n", __func__);
return -EBUSY;
}
len = 0;
page_cnt = 0;
for (i = 0; i < sg_dma_len; ++i) {
unsigned int dma_len = ib_sg_dma_len(dev, &scat[i]);
u64 dma_addr = ib_sg_dma_address(dev, &scat[i]);
if (dma_addr & ~PAGE_MASK) {
if (i > 0)
return -EINVAL;
else
++page_cnt;
}
if ((dma_addr + dma_len) & ~PAGE_MASK) {
if (i < sg_dma_len - 1)
return -EINVAL;
else
++page_cnt;
}
len += dma_len;
}
page_cnt += len >> PAGE_SHIFT;
if (page_cnt > ibmr->pool->fmr_attr.max_pages)
return -EINVAL;
dma_pages = kmalloc_node(sizeof(u64) * page_cnt, GFP_ATOMIC,
rdsibdev_to_node(rds_ibdev));
if (!dma_pages)
return -ENOMEM;
page_cnt = 0;
for (i = 0; i < sg_dma_len; ++i) {
unsigned int dma_len = ib_sg_dma_len(dev, &scat[i]);
u64 dma_addr = ib_sg_dma_address(dev, &scat[i]);
for (j = 0; j < dma_len; j += PAGE_SIZE)
dma_pages[page_cnt++] =
(dma_addr & PAGE_MASK) + j;
}
ret = ib_map_phys_fmr(fmr->fmr, dma_pages, page_cnt, io_addr);
if (ret)
goto out;
/* Success - we successfully remapped the MR, so we can
* safely tear down the old mapping.
*/
rds_ib_teardown_mr(ibmr);
ibmr->sg = scat;
ibmr->sg_len = nents;
ibmr->sg_dma_len = sg_dma_len;
ibmr->remap_count++;
if (ibmr->pool->pool_type == RDS_IB_MR_8K_POOL)
rds_ib_stats_inc(s_ib_rdma_mr_8k_used);
else
rds_ib_stats_inc(s_ib_rdma_mr_1m_used);
ret = 0;
out:
kfree(dma_pages);
return ret;
}
struct rds_ib_mr *rds_ib_reg_fmr(struct rds_ib_device *rds_ibdev,
struct scatterlist *sg,
unsigned long nents,
u32 *key)
{
struct rds_ib_mr *ibmr = NULL;
struct rds_ib_fmr *fmr;
int ret;
ibmr = rds_ib_alloc_fmr(rds_ibdev, nents);
if (IS_ERR(ibmr))
return ibmr;
ibmr->device = rds_ibdev;
fmr = &ibmr->u.fmr;
ret = rds_ib_map_fmr(rds_ibdev, ibmr, sg, nents);
if (ret == 0)
*key = fmr->fmr->rkey;
else
rds_ib_free_mr(ibmr, 0);
return ibmr;
}
void rds_ib_unreg_fmr(struct list_head *list, unsigned int *nfreed,
unsigned long *unpinned, unsigned int goal)
{
struct rds_ib_mr *ibmr, *next;
struct rds_ib_fmr *fmr;
LIST_HEAD(fmr_list);
int ret = 0;
unsigned int freed = *nfreed;
/* String all ib_mr's onto one list and hand them to ib_unmap_fmr */
list_for_each_entry(ibmr, list, unmap_list) {
fmr = &ibmr->u.fmr;
list_add(&fmr->fmr->list, &fmr_list);
}
ret = ib_unmap_fmr(&fmr_list);
if (ret)
pr_warn("RDS/IB: FMR invalidation failed (err=%d)\n", ret);
/* Now we can destroy the DMA mapping and unpin any pages */
list_for_each_entry_safe(ibmr, next, list, unmap_list) {
fmr = &ibmr->u.fmr;
*unpinned += ibmr->sg_len;
__rds_ib_teardown_mr(ibmr);
if (freed < goal ||
ibmr->remap_count >= ibmr->pool->fmr_attr.max_maps) {
if (ibmr->pool->pool_type == RDS_IB_MR_8K_POOL)
rds_ib_stats_inc(s_ib_rdma_mr_8k_free);
else
rds_ib_stats_inc(s_ib_rdma_mr_1m_free);
list_del(&ibmr->unmap_list);
ib_dealloc_fmr(fmr->fmr);
kfree(ibmr);
freed++;
}
}
*nfreed = freed;
}
void rds_ib_free_fmr_list(struct rds_ib_mr *ibmr)
{
struct rds_ib_mr_pool *pool = ibmr->pool;
if (ibmr->remap_count >= pool->fmr_attr.max_maps)
llist_add(&ibmr->llnode, &pool->drop_list);
else
llist_add(&ibmr->llnode, &pool->free_list);
}
ened when shutting down the X
server. The call chains were different:
- VT ioctl(KDSETMODE, KD_TEXT):
intel_cleanup_plane_fb+0x5b/0xa0 [i915]
drm_atomic_helper_cleanup_planes+0x6f/0x90 [drm_kms_helper]
intel_atomic_commit_tail+0x749/0xfe0 [i915]
intel_atomic_commit+0x3cb/0x4f0 [i915]
drm_atomic_commit+0x4b/0x50 [drm]
restore_fbdev_mode+0x14c/0x2a0 [drm_kms_helper]
drm_fb_helper_restore_fbdev_mode_unlocked+0x34/0x80 [drm_kms_helper]
drm_fb_helper_set_par+0x2d/0x60 [drm_kms_helper]
intel_fbdev_set_par+0x18/0x70 [i915]
fb_set_var+0x236/0x460
fbcon_blank+0x30f/0x350
do_unblank_screen+0xd2/0x1a0
vt_ioctl+0x507/0x12a0
tty_ioctl+0x355/0xc30
do_vfs_ioctl+0xa3/0x5e0
SyS_ioctl+0x79/0x90
entry_SYSCALL_64_fastpath+0x13/0x94
- i915 unpin_work workqueue:
intel_unpin_work_fn+0x58/0x140 [i915]
process_one_work+0x1f1/0x480
worker_thread+0x48/0x4d0
kthread+0x101/0x140
and this patch purely papers over the issue by adding a NULL pointer
check and a WARN_ON_ONCE() to avoid the oops that would then generally
make the machine unresponsive.
Other callers of i915_gem_object_to_ggtt() seem to also check for the
returned pointer being NULL and warn about it, so this clearly has
happened before in other places.
[ Reported it originally to the i915 developers on Jan 8, applying the
ugly workaround on my own now after triggering the problem for the
second time with no feedback.
This is likely to be the same bug reported as
https://bugs.freedesktop.org/show_bug.cgi?id=98829
https://bugs.freedesktop.org/show_bug.cgi?id=99134
which has a patch for the underlying problem, but it hasn't gotten to
me, so I'm applying the workaround. ]
Cc: Daniel Vetter <daniel.vetter@intel.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>