/*
* Copyright 2014 Advanced Micro Devices, Inc.
* All Rights Reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sub license, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* 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 NON-INFRINGEMENT. IN NO EVENT SHALL
* THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS 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.
*
* The above copyright notice and this permission notice (including the
* next paragraph) shall be included in all copies or substantial portions
* of the Software.
*
*/
/*
* Authors:
* Christian König <[email protected]>
*/
/**
* DOC: MMU Notifier
*
* For coherent userptr handling registers an MMU notifier to inform the driver
* about updates on the page tables of a process.
*
* When somebody tries to invalidate the page tables we block the update until
* all operations on the pages in question are completed, then those pages are
* marked as accessed and also dirty if it wasn't a read only access.
*
* New command submissions using the userptrs in question are delayed until all
* page table invalidation are completed and we once more see a coherent process
* address space.
*/
#include <linux/firmware.h>
#include <linux/module.h>
#include <drm/drm.h>
#include "amdgpu.h"
#include "amdgpu_amdkfd.h"
#include "amdgpu_hmm.h"
#define MAX_WALK_BYTE (2UL << 30)
/**
* amdgpu_hmm_invalidate_gfx - callback to notify about mm change
*
* @mni: the range (mm) is about to update
* @range: details on the invalidation
* @cur_seq: Value to pass to mmu_interval_set_seq()
*
* Block for operations on BOs to finish and mark pages as accessed and
* potentially dirty.
*/
static bool amdgpu_hmm_invalidate_gfx(struct mmu_interval_notifier *mni,
const struct mmu_notifier_range *range,
unsigned long cur_seq)
{
struct amdgpu_bo *bo = container_of(mni, struct amdgpu_bo, notifier);
struct amdgpu_device *adev = amdgpu_ttm_adev(bo->tbo.bdev);
long r;
if (!mmu_notifier_range_blockable(range))
return false;
mutex_lock(&adev->notifier_lock);
mmu_interval_set_seq(mni, cur_seq);
r = dma_resv_wait_timeout(bo->tbo.base.resv, DMA_RESV_USAGE_BOOKKEEP,
false, MAX_SCHEDULE_TIMEOUT);
mutex_unlock(&adev->notifier_lock);
if (r <= 0)
DRM_ERROR("(%ld) failed to wait for user bo\n", r);
return true;
}
static const struct mmu_interval_notifier_ops amdgpu_hmm_gfx_ops = {
.invalidate = amdgpu_hmm_invalidate_gfx,
};
/**
* amdgpu_hmm_invalidate_hsa - callback to notify about mm change
*
* @mni: the range (mm) is about to update
* @range: details on the invalidation
* @cur_seq: Value to pass to mmu_interval_set_seq()
*
* We temporarily evict the BO attached to this range. This necessitates
* evicting all user-mode queues of the process.
*/
static bool amdgpu_hmm_invalidate_hsa(struct mmu_interval_notifier *mni,
const struct mmu_notifier_range *range,
unsigned long cur_seq)
{
struct amdgpu_bo *bo = container_of(mni, struct amdgpu_bo, notifier);
if (!mmu_notifier_range_blockable(range))
return false;
amdgpu_amdkfd_evict_userptr(mni, cur_seq, bo->kfd_bo);
return true;
}
static const struct mmu_interval_notifier_ops amdgpu_hmm_hsa_ops = {
.invalidate = amdgpu_hmm_invalidate_hsa,
};
/**
* amdgpu_hmm_register - register a BO for notifier updates
*
* @bo: amdgpu buffer object
* @addr: userptr addr we should monitor
*
* Registers a mmu_notifier for the given BO at the specified address.
* Returns 0 on success, -ERRNO if anything goes wrong.
*/
int amdgpu_hmm_register(struct amdgpu_bo *bo, unsigned long addr)
{
int r;
if (bo->kfd_bo)
r = mmu_interval_notifier_insert(&bo->notifier, current->mm,
addr, amdgpu_bo_size(bo),
&amdgpu_hmm_hsa_ops);
else
r = mmu_interval_notifier_insert(&bo->notifier, current->mm, addr,
amdgpu_bo_size(bo),
&amdgpu_hmm_gfx_ops);
if (r)
/*
* Make sure amdgpu_hmm_unregister() doesn't call
* mmu_interval_notifier_remove() when the notifier isn't properly
* initialized.
*/
bo->notifier.mm = NULL;
return r;
}
/**
* amdgpu_hmm_unregister - unregister a BO for notifier updates
*
* @bo: amdgpu buffer object
*
* Remove any registration of mmu notifier updates from the buffer object.
*/
void amdgpu_hmm_unregister(struct amdgpu_bo *bo)
{
if (!bo->notifier.mm)
return;
mmu_interval_notifier_remove(&bo->notifier);
bo->notifier.mm = NULL;
}
int amdgpu_hmm_range_get_pages(struct mmu_interval_notifier *notifier,
uint64_t start, uint64_t npages, bool readonly,
void *owner, struct page **pages,
struct hmm_range **phmm_range)
{
struct hmm_range *hmm_range;
unsigned long end;
unsigned long timeout;
unsigned long i;
unsigned long *pfns;
int r = 0;
hmm_range = kzalloc(sizeof(*hmm_range), GFP_KERNEL);
if (unlikely(!hmm_range))
return -ENOMEM;
pfns = kvmalloc_array(npages, sizeof(*pfns), GFP_KERNEL);
if (unlikely(!pfns)) {
r = -ENOMEM;
goto out_free_range;
}
hmm_range->notifier = notifier;
hmm_range->default_flags = HMM_PFN_REQ_FAULT;
if (!readonly)
hmm_range->default_flags |= HMM_PFN_REQ_WRITE;
hmm_range->hmm_pfns = pfns;
hmm_range->start = start;
end = start + npages * PAGE_SIZE;
hmm_range->dev_private_owner = owner;
do {
hmm_range->end = min(hmm_range->start + MAX_WALK_BYTE, end);
pr_debug("hmm range: start = 0x%lx, end = 0x%lx",
hmm_range->start, hmm_range->end);
timeout = jiffies + msecs_to_jiffies(HMM_RANGE_DEFAULT_TIMEOUT);
retry:
hmm_range->notifier_seq = mmu_interval_read_begin(notifier);
r = hmm_range_fault(hmm_range);
if (unlikely(r)) {
if (r == -EBUSY && !time_after(jiffies, timeout))
goto retry;
goto out_free_pfns;
}
if (hmm_range->end == end)
break;
hmm_range->hmm_pfns += MAX_WALK_BYTE >> PAGE_SHIFT;
hmm_range->start = hmm_range->end;
} while (hmm_range->end < end);
hmm_range->start = start;
hmm_range->hmm_pfns = pfns;
/*
* Due to default_flags, all pages are HMM_PFN_VALID or
* hmm_range_fault() fails. FIXME: The pages cannot be touched outside
* the notifier_lock, and mmu_interval_read_retry() must be done first.
*/
for (i = 0; pages && i < npages; i++)
pages[i] = hmm_pfn_to_page(pfns[i]);
*phmm_range = hmm_range;
return 0;
out_free_pfns:
kvfree(pfns);
out_free_range:
kfree(hmm_range);
if (r == -EBUSY)
r = -EAGAIN;
return r;
}
bool amdgpu_hmm_range_get_pages_done(struct hmm_range *hmm_range)
{
bool r;
r = mmu_interval_read_retry(hmm_range->notifier,
hmm_range->notifier_seq);
kvfree(hmm_range->hmm_pfns);
kfree(hmm_range);
return r;
}
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