471 lines
14 KiB
C
471 lines
14 KiB
C
|
// SPDX-License-Identifier: GPL-2.0 OR MIT
|
||
|
|
/**************************************************************************
|
||
|
|
*
|
||
|
|
* Copyright 2019 VMware, Inc., Palo Alto, CA., USA
|
||
|
|
*
|
||
|
|
* 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 above copyright notice and this permission notice (including the
|
||
|
|
* next paragraph) shall be included in all copies or substantial portions
|
||
|
|
* of the Software.
|
||
|
|
*
|
||
|
|
* 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.
|
||
|
|
*
|
||
|
|
**************************************************************************/
|
||
|
|
#include "vmwgfx_drv.h"
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Different methods for tracking dirty:
|
||
|
|
* VMW_BO_DIRTY_PAGETABLE - Scan the pagetable for hardware dirty bits
|
||
|
|
* VMW_BO_DIRTY_MKWRITE - Write-protect page table entries and record write-
|
||
|
|
* accesses in the VM mkwrite() callback
|
||
|
|
*/
|
||
|
|
enum vmw_bo_dirty_method {
|
||
|
|
VMW_BO_DIRTY_PAGETABLE,
|
||
|
|
VMW_BO_DIRTY_MKWRITE,
|
||
|
|
};
|
||
|
|
|
||
|
|
/*
|
||
|
|
* No dirtied pages at scan trigger a transition to the _MKWRITE method,
|
||
|
|
* similarly a certain percentage of dirty pages trigger a transition to
|
||
|
|
* the _PAGETABLE method. How many triggers should we wait for before
|
||
|
|
* changing method?
|
||
|
|
*/
|
||
|
|
#define VMW_DIRTY_NUM_CHANGE_TRIGGERS 2
|
||
|
|
|
||
|
|
/* Percentage to trigger a transition to the _PAGETABLE method */
|
||
|
|
#define VMW_DIRTY_PERCENTAGE 10
|
||
|
|
|
||
|
|
/**
|
||
|
|
* struct vmw_bo_dirty - Dirty information for buffer objects
|
||
|
|
* @start: First currently dirty bit
|
||
|
|
* @end: Last currently dirty bit + 1
|
||
|
|
* @method: The currently used dirty method
|
||
|
|
* @change_count: Number of consecutive method change triggers
|
||
|
|
* @ref_count: Reference count for this structure
|
||
|
|
* @bitmap_size: The size of the bitmap in bits. Typically equal to the
|
||
|
|
* nuber of pages in the bo.
|
||
|
|
* @bitmap: A bitmap where each bit represents a page. A set bit means a
|
||
|
|
* dirty page.
|
||
|
|
*/
|
||
|
|
struct vmw_bo_dirty {
|
||
|
|
unsigned long start;
|
||
|
|
unsigned long end;
|
||
|
|
enum vmw_bo_dirty_method method;
|
||
|
|
unsigned int change_count;
|
||
|
|
unsigned int ref_count;
|
||
|
|
unsigned long bitmap_size;
|
||
|
|
unsigned long bitmap[];
|
||
|
|
};
|
||
|
|
|
||
|
|
/**
|
||
|
|
* vmw_bo_dirty_scan_pagetable - Perform a pagetable scan for dirty bits
|
||
|
|
* @vbo: The buffer object to scan
|
||
|
|
*
|
||
|
|
* Scans the pagetable for dirty bits. Clear those bits and modify the
|
||
|
|
* dirty structure with the results. This function may change the
|
||
|
|
* dirty-tracking method.
|
||
|
|
*/
|
||
|
|
static void vmw_bo_dirty_scan_pagetable(struct vmw_buffer_object *vbo)
|
||
|
|
{
|
||
|
|
struct vmw_bo_dirty *dirty = vbo->dirty;
|
||
|
|
pgoff_t offset = drm_vma_node_start(&vbo->base.base.vma_node);
|
||
|
|
struct address_space *mapping = vbo->base.bdev->dev_mapping;
|
||
|
|
pgoff_t num_marked;
|
||
|
|
|
||
|
|
num_marked = clean_record_shared_mapping_range
|
||
|
|
(mapping,
|
||
|
|
offset, dirty->bitmap_size,
|
||
|
|
offset, &dirty->bitmap[0],
|
||
|
|
&dirty->start, &dirty->end);
|
||
|
|
if (num_marked == 0)
|
||
|
|
dirty->change_count++;
|
||
|
|
else
|
||
|
|
dirty->change_count = 0;
|
||
|
|
|
||
|
|
if (dirty->change_count > VMW_DIRTY_NUM_CHANGE_TRIGGERS) {
|
||
|
|
dirty->change_count = 0;
|
||
|
|
dirty->method = VMW_BO_DIRTY_MKWRITE;
|
||
|
|
wp_shared_mapping_range(mapping,
|
||
|
|
offset, dirty->bitmap_size);
|
||
|
|
clean_record_shared_mapping_range(mapping,
|
||
|
|
offset, dirty->bitmap_size,
|
||
|
|
offset, &dirty->bitmap[0],
|
||
|
|
&dirty->start, &dirty->end);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* vmw_bo_dirty_scan_mkwrite - Reset the mkwrite dirty-tracking method
|
||
|
|
* @vbo: The buffer object to scan
|
||
|
|
*
|
||
|
|
* Write-protect pages written to so that consecutive write accesses will
|
||
|
|
* trigger a call to mkwrite.
|
||
|
|
*
|
||
|
|
* This function may change the dirty-tracking method.
|
||
|
|
*/
|
||
|
|
static void vmw_bo_dirty_scan_mkwrite(struct vmw_buffer_object *vbo)
|
||
|
|
{
|
||
|
|
struct vmw_bo_dirty *dirty = vbo->dirty;
|
||
|
|
unsigned long offset = drm_vma_node_start(&vbo->base.base.vma_node);
|
||
|
|
struct address_space *mapping = vbo->base.bdev->dev_mapping;
|
||
|
|
pgoff_t num_marked;
|
||
|
|
|
||
|
|
if (dirty->end <= dirty->start)
|
||
|
|
return;
|
||
|
|
|
||
|
|
num_marked = wp_shared_mapping_range(vbo->base.bdev->dev_mapping,
|
||
|
|
dirty->start + offset,
|
||
|
|
dirty->end - dirty->start);
|
||
|
|
|
||
|
|
if (100UL * num_marked / dirty->bitmap_size >
|
||
|
|
VMW_DIRTY_PERCENTAGE) {
|
||
|
|
dirty->change_count++;
|
||
|
|
} else {
|
||
|
|
dirty->change_count = 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
if (dirty->change_count > VMW_DIRTY_NUM_CHANGE_TRIGGERS) {
|
||
|
|
pgoff_t start = 0;
|
||
|
|
pgoff_t end = dirty->bitmap_size;
|
||
|
|
|
||
|
|
dirty->method = VMW_BO_DIRTY_PAGETABLE;
|
||
|
|
clean_record_shared_mapping_range(mapping, offset, end, offset,
|
||
|
|
&dirty->bitmap[0],
|
||
|
|
&start, &end);
|
||
|
|
bitmap_clear(&dirty->bitmap[0], 0, dirty->bitmap_size);
|
||
|
|
if (dirty->start < dirty->end)
|
||
|
|
bitmap_set(&dirty->bitmap[0], dirty->start,
|
||
|
|
dirty->end - dirty->start);
|
||
|
|
dirty->change_count = 0;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* vmw_bo_dirty_scan - Scan for dirty pages and add them to the dirty
|
||
|
|
* tracking structure
|
||
|
|
* @vbo: The buffer object to scan
|
||
|
|
*
|
||
|
|
* This function may change the dirty tracking method.
|
||
|
|
*/
|
||
|
|
void vmw_bo_dirty_scan(struct vmw_buffer_object *vbo)
|
||
|
|
{
|
||
|
|
struct vmw_bo_dirty *dirty = vbo->dirty;
|
||
|
|
|
||
|
|
if (dirty->method == VMW_BO_DIRTY_PAGETABLE)
|
||
|
|
vmw_bo_dirty_scan_pagetable(vbo);
|
||
|
|
else
|
||
|
|
vmw_bo_dirty_scan_mkwrite(vbo);
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* vmw_bo_dirty_pre_unmap - write-protect and pick up dirty pages before
|
||
|
|
* an unmap_mapping_range operation.
|
||
|
|
* @vbo: The buffer object,
|
||
|
|
* @start: First page of the range within the buffer object.
|
||
|
|
* @end: Last page of the range within the buffer object + 1.
|
||
|
|
*
|
||
|
|
* If we're using the _PAGETABLE scan method, we may leak dirty pages
|
||
|
|
* when calling unmap_mapping_range(). This function makes sure we pick
|
||
|
|
* up all dirty pages.
|
||
|
|
*/
|
||
|
|
static void vmw_bo_dirty_pre_unmap(struct vmw_buffer_object *vbo,
|
||
|
|
pgoff_t start, pgoff_t end)
|
||
|
|
{
|
||
|
|
struct vmw_bo_dirty *dirty = vbo->dirty;
|
||
|
|
unsigned long offset = drm_vma_node_start(&vbo->base.base.vma_node);
|
||
|
|
struct address_space *mapping = vbo->base.bdev->dev_mapping;
|
||
|
|
|
||
|
|
if (dirty->method != VMW_BO_DIRTY_PAGETABLE || start >= end)
|
||
|
|
return;
|
||
|
|
|
||
|
|
wp_shared_mapping_range(mapping, start + offset, end - start);
|
||
|
|
clean_record_shared_mapping_range(mapping, start + offset,
|
||
|
|
end - start, offset,
|
||
|
|
&dirty->bitmap[0], &dirty->start,
|
||
|
|
&dirty->end);
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* vmw_bo_dirty_unmap - Clear all ptes pointing to a range within a bo
|
||
|
|
* @vbo: The buffer object,
|
||
|
|
* @start: First page of the range within the buffer object.
|
||
|
|
* @end: Last page of the range within the buffer object + 1.
|
||
|
|
*
|
||
|
|
* This is similar to ttm_bo_unmap_virtual() except it takes a subrange.
|
||
|
|
*/
|
||
|
|
void vmw_bo_dirty_unmap(struct vmw_buffer_object *vbo,
|
||
|
|
pgoff_t start, pgoff_t end)
|
||
|
|
{
|
||
|
|
unsigned long offset = drm_vma_node_start(&vbo->base.base.vma_node);
|
||
|
|
struct address_space *mapping = vbo->base.bdev->dev_mapping;
|
||
|
|
|
||
|
|
vmw_bo_dirty_pre_unmap(vbo, start, end);
|
||
|
|
unmap_shared_mapping_range(mapping, (offset + start) << PAGE_SHIFT,
|
||
|
|
(loff_t) (end - start) << PAGE_SHIFT);
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* vmw_bo_dirty_add - Add a dirty-tracking user to a buffer object
|
||
|
|
* @vbo: The buffer object
|
||
|
|
*
|
||
|
|
* This function registers a dirty-tracking user to a buffer object.
|
||
|
|
* A user can be for example a resource or a vma in a special user-space
|
||
|
|
* mapping.
|
||
|
|
*
|
||
|
|
* Return: Zero on success, -ENOMEM on memory allocation failure.
|
||
|
|
*/
|
||
|
|
int vmw_bo_dirty_add(struct vmw_buffer_object *vbo)
|
||
|
|
{
|
||
|
|
struct vmw_bo_dirty *dirty = vbo->dirty;
|
||
|
|
pgoff_t num_pages = PFN_UP(vbo->base.resource->size);
|
||
|
|
size_t size;
|
||
|
|
int ret;
|
||
|
|
|
||
|
|
if (dirty) {
|
||
|
|
dirty->ref_count++;
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
size = sizeof(*dirty) + BITS_TO_LONGS(num_pages) * sizeof(long);
|
||
|
|
dirty = kvzalloc(size, GFP_KERNEL);
|
||
|
|
if (!dirty) {
|
||
|
|
ret = -ENOMEM;
|
||
|
|
goto out_no_dirty;
|
||
|
|
}
|
||
|
|
|
||
|
|
dirty->bitmap_size = num_pages;
|
||
|
|
dirty->start = dirty->bitmap_size;
|
||
|
|
dirty->end = 0;
|
||
|
|
dirty->ref_count = 1;
|
||
|
|
if (num_pages < PAGE_SIZE / sizeof(pte_t)) {
|
||
|
|
dirty->method = VMW_BO_DIRTY_PAGETABLE;
|
||
|
|
} else {
|
||
|
|
struct address_space *mapping = vbo->base.bdev->dev_mapping;
|
||
|
|
pgoff_t offset = drm_vma_node_start(&vbo->base.base.vma_node);
|
||
|
|
|
||
|
|
dirty->method = VMW_BO_DIRTY_MKWRITE;
|
||
|
|
|
||
|
|
/* Write-protect and then pick up already dirty bits */
|
||
|
|
wp_shared_mapping_range(mapping, offset, num_pages);
|
||
|
|
clean_record_shared_mapping_range(mapping, offset, num_pages,
|
||
|
|
offset,
|
||
|
|
&dirty->bitmap[0],
|
||
|
|
&dirty->start, &dirty->end);
|
||
|
|
}
|
||
|
|
|
||
|
|
vbo->dirty = dirty;
|
||
|
|
|
||
|
|
return 0;
|
||
|
|
|
||
|
|
out_no_dirty:
|
||
|
|
return ret;
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* vmw_bo_dirty_release - Release a dirty-tracking user from a buffer object
|
||
|
|
* @vbo: The buffer object
|
||
|
|
*
|
||
|
|
* This function releases a dirty-tracking user from a buffer object.
|
||
|
|
* If the reference count reaches zero, then the dirty-tracking object is
|
||
|
|
* freed and the pointer to it cleared.
|
||
|
|
*
|
||
|
|
* Return: Zero on success, -ENOMEM on memory allocation failure.
|
||
|
|
*/
|
||
|
|
void vmw_bo_dirty_release(struct vmw_buffer_object *vbo)
|
||
|
|
{
|
||
|
|
struct vmw_bo_dirty *dirty = vbo->dirty;
|
||
|
|
|
||
|
|
if (dirty && --dirty->ref_count == 0) {
|
||
|
|
kvfree(dirty);
|
||
|
|
vbo->dirty = NULL;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* vmw_bo_dirty_transfer_to_res - Pick up a resource's dirty region from
|
||
|
|
* its backing mob.
|
||
|
|
* @res: The resource
|
||
|
|
*
|
||
|
|
* This function will pick up all dirty ranges affecting the resource from
|
||
|
|
* it's backup mob, and call vmw_resource_dirty_update() once for each
|
||
|
|
* range. The transferred ranges will be cleared from the backing mob's
|
||
|
|
* dirty tracking.
|
||
|
|
*/
|
||
|
|
void vmw_bo_dirty_transfer_to_res(struct vmw_resource *res)
|
||
|
|
{
|
||
|
|
struct vmw_buffer_object *vbo = res->backup;
|
||
|
|
struct vmw_bo_dirty *dirty = vbo->dirty;
|
||
|
|
pgoff_t start, cur, end;
|
||
|
|
unsigned long res_start = res->backup_offset;
|
||
|
|
unsigned long res_end = res->backup_offset + res->backup_size;
|
||
|
|
|
||
|
|
WARN_ON_ONCE(res_start & ~PAGE_MASK);
|
||
|
|
res_start >>= PAGE_SHIFT;
|
||
|
|
res_end = DIV_ROUND_UP(res_end, PAGE_SIZE);
|
||
|
|
|
||
|
|
if (res_start >= dirty->end || res_end <= dirty->start)
|
||
|
|
return;
|
||
|
|
|
||
|
|
cur = max(res_start, dirty->start);
|
||
|
|
res_end = max(res_end, dirty->end);
|
||
|
|
while (cur < res_end) {
|
||
|
|
unsigned long num;
|
||
|
|
|
||
|
|
start = find_next_bit(&dirty->bitmap[0], res_end, cur);
|
||
|
|
if (start >= res_end)
|
||
|
|
break;
|
||
|
|
|
||
|
|
end = find_next_zero_bit(&dirty->bitmap[0], res_end, start + 1);
|
||
|
|
cur = end + 1;
|
||
|
|
num = end - start;
|
||
|
|
bitmap_clear(&dirty->bitmap[0], start, num);
|
||
|
|
vmw_resource_dirty_update(res, start, end);
|
||
|
|
}
|
||
|
|
|
||
|
|
if (res_start <= dirty->start && res_end > dirty->start)
|
||
|
|
dirty->start = res_end;
|
||
|
|
if (res_start < dirty->end && res_end >= dirty->end)
|
||
|
|
dirty->end = res_start;
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* vmw_bo_dirty_clear_res - Clear a resource's dirty region from
|
||
|
|
* its backing mob.
|
||
|
|
* @res: The resource
|
||
|
|
*
|
||
|
|
* This function will clear all dirty ranges affecting the resource from
|
||
|
|
* it's backup mob's dirty tracking.
|
||
|
|
*/
|
||
|
|
void vmw_bo_dirty_clear_res(struct vmw_resource *res)
|
||
|
|
{
|
||
|
|
unsigned long res_start = res->backup_offset;
|
||
|
|
unsigned long res_end = res->backup_offset + res->backup_size;
|
||
|
|
struct vmw_buffer_object *vbo = res->backup;
|
||
|
|
struct vmw_bo_dirty *dirty = vbo->dirty;
|
||
|
|
|
||
|
|
res_start >>= PAGE_SHIFT;
|
||
|
|
res_end = DIV_ROUND_UP(res_end, PAGE_SIZE);
|
||
|
|
|
||
|
|
if (res_start >= dirty->end || res_end <= dirty->start)
|
||
|
|
return;
|
||
|
|
|
||
|
|
res_start = max(res_start, dirty->start);
|
||
|
|
res_end = min(res_end, dirty->end);
|
||
|
|
bitmap_clear(&dirty->bitmap[0], res_start, res_end - res_start);
|
||
|
|
|
||
|
|
if (res_start <= dirty->start && res_end > dirty->start)
|
||
|
|
dirty->start = res_end;
|
||
|
|
if (res_start < dirty->end && res_end >= dirty->end)
|
||
|
|
dirty->end = res_start;
|
||
|
|
}
|
||
|
|
|
||
|
|
vm_fault_t vmw_bo_vm_mkwrite(struct vm_fault *vmf)
|
||
|
|
{
|
||
|
|
struct vm_area_struct *vma = vmf->vma;
|
||
|
|
struct ttm_buffer_object *bo = (struct ttm_buffer_object *)
|
||
|
|
vma->vm_private_data;
|
||
|
|
vm_fault_t ret;
|
||
|
|
unsigned long page_offset;
|
||
|
|
unsigned int save_flags;
|
||
|
|
struct vmw_buffer_object *vbo =
|
||
|
|
container_of(bo, typeof(*vbo), base);
|
||
|
|
|
||
|
|
/*
|
||
|
|
* mkwrite() doesn't handle the VM_FAULT_RETRY return value correctly.
|
||
|
|
* So make sure the TTM helpers are aware.
|
||
|
|
*/
|
||
|
|
save_flags = vmf->flags;
|
||
|
|
vmf->flags &= ~FAULT_FLAG_ALLOW_RETRY;
|
||
|
|
ret = ttm_bo_vm_reserve(bo, vmf);
|
||
|
|
vmf->flags = save_flags;
|
||
|
|
if (ret)
|
||
|
|
return ret;
|
||
|
|
|
||
|
|
page_offset = vmf->pgoff - drm_vma_node_start(&bo->base.vma_node);
|
||
|
|
if (unlikely(page_offset >= PFN_UP(bo->resource->size))) {
|
||
|
|
ret = VM_FAULT_SIGBUS;
|
||
|
|
goto out_unlock;
|
||
|
|
}
|
||
|
|
|
||
|
|
if (vbo->dirty && vbo->dirty->method == VMW_BO_DIRTY_MKWRITE &&
|
||
|
|
!test_bit(page_offset, &vbo->dirty->bitmap[0])) {
|
||
|
|
struct vmw_bo_dirty *dirty = vbo->dirty;
|
||
|
|
|
||
|
|
__set_bit(page_offset, &dirty->bitmap[0]);
|
||
|
|
dirty->start = min(dirty->start, page_offset);
|
||
|
|
dirty->end = max(dirty->end, page_offset + 1);
|
||
|
|
}
|
||
|
|
|
||
|
|
out_unlock:
|
||
|
|
dma_resv_unlock(bo->base.resv);
|
||
|
|
return ret;
|
||
|
|
}
|
||
|
|
|
||
|
|
vm_fault_t vmw_bo_vm_fault(struct vm_fault *vmf)
|
||
|
|
{
|
||
|
|
struct vm_area_struct *vma = vmf->vma;
|
||
|
|
struct ttm_buffer_object *bo = (struct ttm_buffer_object *)
|
||
|
|
vma->vm_private_data;
|
||
|
|
struct vmw_buffer_object *vbo =
|
||
|
|
container_of(bo, struct vmw_buffer_object, base);
|
||
|
|
pgoff_t num_prefault;
|
||
|
|
pgprot_t prot;
|
||
|
|
vm_fault_t ret;
|
||
|
|
|
||
|
|
ret = ttm_bo_vm_reserve(bo, vmf);
|
||
|
|
if (ret)
|
||
|
|
return ret;
|
||
|
|
|
||
|
|
num_prefault = (vma->vm_flags & VM_RAND_READ) ? 1 :
|
||
|
|
TTM_BO_VM_NUM_PREFAULT;
|
||
|
|
|
||
|
|
if (vbo->dirty) {
|
||
|
|
pgoff_t allowed_prefault;
|
||
|
|
unsigned long page_offset;
|
||
|
|
|
||
|
|
page_offset = vmf->pgoff -
|
||
|
|
drm_vma_node_start(&bo->base.vma_node);
|
||
|
|
if (page_offset >= PFN_UP(bo->resource->size) ||
|
||
|
|
vmw_resources_clean(vbo, page_offset,
|
||
|
|
page_offset + PAGE_SIZE,
|
||
|
|
&allowed_prefault)) {
|
||
|
|
ret = VM_FAULT_SIGBUS;
|
||
|
|
goto out_unlock;
|
||
|
|
}
|
||
|
|
|
||
|
|
num_prefault = min(num_prefault, allowed_prefault);
|
||
|
|
}
|
||
|
|
|
||
|
|
/*
|
||
|
|
* If we don't track dirty using the MKWRITE method, make sure
|
||
|
|
* sure the page protection is write-enabled so we don't get
|
||
|
|
* a lot of unnecessary write faults.
|
||
|
|
*/
|
||
|
|
if (vbo->dirty && vbo->dirty->method == VMW_BO_DIRTY_MKWRITE)
|
||
|
|
prot = vm_get_page_prot(vma->vm_flags & ~VM_SHARED);
|
||
|
|
else
|
||
|
|
prot = vm_get_page_prot(vma->vm_flags);
|
||
|
|
|
||
|
|
ret = ttm_bo_vm_fault_reserved(vmf, prot, num_prefault);
|
||
|
|
if (ret == VM_FAULT_RETRY && !(vmf->flags & FAULT_FLAG_RETRY_NOWAIT))
|
||
|
|
return ret;
|
||
|
|
|
||
|
|
out_unlock:
|
||
|
|
dma_resv_unlock(bo->base.resv);
|
||
|
|
|
||
|
|
return ret;
|
||
|
|
}
|