linux_dsm_epyc7002/drivers/gpu/drm/msm/msm_gem_submit.c
Rob Clark 93ddb0d3b0 drm/msm: validate flags, etc
After reading a nice article on LWN[1], I went back and double checked
my handling of invalid-input checking.  Turns out there were a couple
places I had missed.

Since the driver is fairly young, and the devices it supports are really
only just barely usable for basic stuff (serial console) with an
upstream kernel, I think we should fix this now and revert specific
parts of this patch later in the unlikely event that a regression is
reported.

[1] https://lwn.net/Articles/588444/

Signed-off-by: Rob Clark <robdclark@gmail.com>
2014-03-31 10:27:46 -04:00

427 lines
9.8 KiB
C

/*
* Copyright (C) 2013 Red Hat
* Author: Rob Clark <robdclark@gmail.com>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 as published by
* the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License along with
* this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include "msm_drv.h"
#include "msm_gpu.h"
#include "msm_gem.h"
/*
* Cmdstream submission:
*/
/* make sure these don't conflict w/ MSM_SUBMIT_BO_x */
#define BO_VALID 0x8000
#define BO_LOCKED 0x4000
#define BO_PINNED 0x2000
static inline void __user *to_user_ptr(u64 address)
{
return (void __user *)(uintptr_t)address;
}
static struct msm_gem_submit *submit_create(struct drm_device *dev,
struct msm_gpu *gpu, int nr)
{
struct msm_gem_submit *submit;
int sz = sizeof(*submit) + (nr * sizeof(submit->bos[0]));
submit = kmalloc(sz, GFP_TEMPORARY | __GFP_NOWARN | __GFP_NORETRY);
if (submit) {
submit->dev = dev;
submit->gpu = gpu;
/* initially, until copy_from_user() and bo lookup succeeds: */
submit->nr_bos = 0;
submit->nr_cmds = 0;
INIT_LIST_HEAD(&submit->bo_list);
ww_acquire_init(&submit->ticket, &reservation_ww_class);
}
return submit;
}
static int submit_lookup_objects(struct msm_gem_submit *submit,
struct drm_msm_gem_submit *args, struct drm_file *file)
{
unsigned i;
int ret = 0;
spin_lock(&file->table_lock);
for (i = 0; i < args->nr_bos; i++) {
struct drm_msm_gem_submit_bo submit_bo;
struct drm_gem_object *obj;
struct msm_gem_object *msm_obj;
void __user *userptr =
to_user_ptr(args->bos + (i * sizeof(submit_bo)));
ret = copy_from_user(&submit_bo, userptr, sizeof(submit_bo));
if (ret) {
ret = -EFAULT;
goto out_unlock;
}
if (submit_bo.flags & ~MSM_SUBMIT_BO_FLAGS) {
DRM_ERROR("invalid flags: %x\n", submit_bo.flags);
ret = -EINVAL;
goto out_unlock;
}
submit->bos[i].flags = submit_bo.flags;
/* in validate_objects() we figure out if this is true: */
submit->bos[i].iova = submit_bo.presumed;
/* normally use drm_gem_object_lookup(), but for bulk lookup
* all under single table_lock just hit object_idr directly:
*/
obj = idr_find(&file->object_idr, submit_bo.handle);
if (!obj) {
DRM_ERROR("invalid handle %u at index %u\n", submit_bo.handle, i);
ret = -EINVAL;
goto out_unlock;
}
msm_obj = to_msm_bo(obj);
if (!list_empty(&msm_obj->submit_entry)) {
DRM_ERROR("handle %u at index %u already on submit list\n",
submit_bo.handle, i);
ret = -EINVAL;
goto out_unlock;
}
drm_gem_object_reference(obj);
submit->bos[i].obj = msm_obj;
list_add_tail(&msm_obj->submit_entry, &submit->bo_list);
}
out_unlock:
submit->nr_bos = i;
spin_unlock(&file->table_lock);
return ret;
}
static void submit_unlock_unpin_bo(struct msm_gem_submit *submit, int i)
{
struct msm_gem_object *msm_obj = submit->bos[i].obj;
if (submit->bos[i].flags & BO_PINNED)
msm_gem_put_iova(&msm_obj->base, submit->gpu->id);
if (submit->bos[i].flags & BO_LOCKED)
ww_mutex_unlock(&msm_obj->resv->lock);
if (!(submit->bos[i].flags & BO_VALID))
submit->bos[i].iova = 0;
submit->bos[i].flags &= ~(BO_LOCKED | BO_PINNED);
}
/* This is where we make sure all the bo's are reserved and pin'd: */
static int submit_validate_objects(struct msm_gem_submit *submit)
{
int contended, slow_locked = -1, i, ret = 0;
retry:
submit->valid = true;
for (i = 0; i < submit->nr_bos; i++) {
struct msm_gem_object *msm_obj = submit->bos[i].obj;
uint32_t iova;
if (slow_locked == i)
slow_locked = -1;
contended = i;
if (!(submit->bos[i].flags & BO_LOCKED)) {
ret = ww_mutex_lock_interruptible(&msm_obj->resv->lock,
&submit->ticket);
if (ret)
goto fail;
submit->bos[i].flags |= BO_LOCKED;
}
/* if locking succeeded, pin bo: */
ret = msm_gem_get_iova_locked(&msm_obj->base,
submit->gpu->id, &iova);
/* this would break the logic in the fail path.. there is no
* reason for this to happen, but just to be on the safe side
* let's notice if this starts happening in the future:
*/
WARN_ON(ret == -EDEADLK);
if (ret)
goto fail;
submit->bos[i].flags |= BO_PINNED;
if (iova == submit->bos[i].iova) {
submit->bos[i].flags |= BO_VALID;
} else {
submit->bos[i].iova = iova;
submit->bos[i].flags &= ~BO_VALID;
submit->valid = false;
}
}
ww_acquire_done(&submit->ticket);
return 0;
fail:
for (; i >= 0; i--)
submit_unlock_unpin_bo(submit, i);
if (slow_locked > 0)
submit_unlock_unpin_bo(submit, slow_locked);
if (ret == -EDEADLK) {
struct msm_gem_object *msm_obj = submit->bos[contended].obj;
/* we lost out in a seqno race, lock and retry.. */
ret = ww_mutex_lock_slow_interruptible(&msm_obj->resv->lock,
&submit->ticket);
if (!ret) {
submit->bos[contended].flags |= BO_LOCKED;
slow_locked = contended;
goto retry;
}
}
return ret;
}
static int submit_bo(struct msm_gem_submit *submit, uint32_t idx,
struct msm_gem_object **obj, uint32_t *iova, bool *valid)
{
if (idx >= submit->nr_bos) {
DRM_ERROR("invalid buffer index: %u (out of %u)\n",
idx, submit->nr_bos);
return -EINVAL;
}
if (obj)
*obj = submit->bos[idx].obj;
if (iova)
*iova = submit->bos[idx].iova;
if (valid)
*valid = !!(submit->bos[idx].flags & BO_VALID);
return 0;
}
/* process the reloc's and patch up the cmdstream as needed: */
static int submit_reloc(struct msm_gem_submit *submit, struct msm_gem_object *obj,
uint32_t offset, uint32_t nr_relocs, uint64_t relocs)
{
uint32_t i, last_offset = 0;
uint32_t *ptr;
int ret;
if (offset % 4) {
DRM_ERROR("non-aligned cmdstream buffer: %u\n", offset);
return -EINVAL;
}
/* For now, just map the entire thing. Eventually we probably
* to do it page-by-page, w/ kmap() if not vmap()d..
*/
ptr = msm_gem_vaddr_locked(&obj->base);
if (IS_ERR(ptr)) {
ret = PTR_ERR(ptr);
DBG("failed to map: %d", ret);
return ret;
}
for (i = 0; i < nr_relocs; i++) {
struct drm_msm_gem_submit_reloc submit_reloc;
void __user *userptr =
to_user_ptr(relocs + (i * sizeof(submit_reloc)));
uint32_t iova, off;
bool valid;
ret = copy_from_user(&submit_reloc, userptr, sizeof(submit_reloc));
if (ret)
return -EFAULT;
if (submit_reloc.submit_offset % 4) {
DRM_ERROR("non-aligned reloc offset: %u\n",
submit_reloc.submit_offset);
return -EINVAL;
}
/* offset in dwords: */
off = submit_reloc.submit_offset / 4;
if ((off >= (obj->base.size / 4)) ||
(off < last_offset)) {
DRM_ERROR("invalid offset %u at reloc %u\n", off, i);
return -EINVAL;
}
ret = submit_bo(submit, submit_reloc.reloc_idx, NULL, &iova, &valid);
if (ret)
return ret;
if (valid)
continue;
iova += submit_reloc.reloc_offset;
if (submit_reloc.shift < 0)
iova >>= -submit_reloc.shift;
else
iova <<= submit_reloc.shift;
ptr[off] = iova | submit_reloc.or;
last_offset = off;
}
return 0;
}
static void submit_cleanup(struct msm_gem_submit *submit, bool fail)
{
unsigned i;
for (i = 0; i < submit->nr_bos; i++) {
struct msm_gem_object *msm_obj = submit->bos[i].obj;
submit_unlock_unpin_bo(submit, i);
list_del_init(&msm_obj->submit_entry);
drm_gem_object_unreference(&msm_obj->base);
}
ww_acquire_fini(&submit->ticket);
kfree(submit);
}
int msm_ioctl_gem_submit(struct drm_device *dev, void *data,
struct drm_file *file)
{
struct msm_drm_private *priv = dev->dev_private;
struct drm_msm_gem_submit *args = data;
struct msm_file_private *ctx = file->driver_priv;
struct msm_gem_submit *submit;
struct msm_gpu *gpu;
unsigned i;
int ret;
/* for now, we just have 3d pipe.. eventually this would need to
* be more clever to dispatch to appropriate gpu module:
*/
if (args->pipe != MSM_PIPE_3D0)
return -EINVAL;
gpu = priv->gpu;
if (args->nr_cmds > MAX_CMDS)
return -EINVAL;
mutex_lock(&dev->struct_mutex);
submit = submit_create(dev, gpu, args->nr_bos);
if (!submit) {
ret = -ENOMEM;
goto out;
}
ret = submit_lookup_objects(submit, args, file);
if (ret)
goto out;
ret = submit_validate_objects(submit);
if (ret)
goto out;
for (i = 0; i < args->nr_cmds; i++) {
struct drm_msm_gem_submit_cmd submit_cmd;
void __user *userptr =
to_user_ptr(args->cmds + (i * sizeof(submit_cmd)));
struct msm_gem_object *msm_obj;
uint32_t iova;
ret = copy_from_user(&submit_cmd, userptr, sizeof(submit_cmd));
if (ret) {
ret = -EFAULT;
goto out;
}
/* validate input from userspace: */
switch (submit_cmd.type) {
case MSM_SUBMIT_CMD_BUF:
case MSM_SUBMIT_CMD_IB_TARGET_BUF:
case MSM_SUBMIT_CMD_CTX_RESTORE_BUF:
break;
default:
DRM_ERROR("invalid type: %08x\n", submit_cmd.type);
ret = -EINVAL;
goto out;
}
ret = submit_bo(submit, submit_cmd.submit_idx,
&msm_obj, &iova, NULL);
if (ret)
goto out;
if (submit_cmd.size % 4) {
DRM_ERROR("non-aligned cmdstream buffer size: %u\n",
submit_cmd.size);
ret = -EINVAL;
goto out;
}
if ((submit_cmd.size + submit_cmd.submit_offset) >=
msm_obj->base.size) {
DRM_ERROR("invalid cmdstream size: %u\n", submit_cmd.size);
ret = -EINVAL;
goto out;
}
submit->cmd[i].type = submit_cmd.type;
submit->cmd[i].size = submit_cmd.size / 4;
submit->cmd[i].iova = iova + submit_cmd.submit_offset;
if (submit->valid)
continue;
ret = submit_reloc(submit, msm_obj, submit_cmd.submit_offset,
submit_cmd.nr_relocs, submit_cmd.relocs);
if (ret)
goto out;
}
submit->nr_cmds = i;
ret = msm_gpu_submit(gpu, submit, ctx);
args->fence = submit->fence;
out:
if (submit)
submit_cleanup(submit, !!ret);
mutex_unlock(&dev->struct_mutex);
return ret;
}