linux/drivers/gpu/drm/ttm/ttm_bo_vm.c
Jerome Glisse b1e5f17232 drm/ttm: introduce callback for ttm_tt populate & unpopulate V4
Move the page allocation and freeing to driver callback and
provide ttm code helper function for those.

Most intrusive change, is the fact that we now only fully
populate an object this simplify some of code designed around
the page fault design.

V2 Rebase on top of memory accounting overhaul
V3 New rebase on top of more memory accouting changes
V4 Rebase on top of no memory account changes (where/when is my
   delorean when i need it ?)

Signed-off-by: Jerome Glisse <jglisse@redhat.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com>
2011-12-06 10:39:24 +00:00

465 lines
11 KiB
C

/**************************************************************************
*
* Copyright (c) 2006-2009 VMware, Inc., Palo Alto, CA., USA
* 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 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.
*
**************************************************************************/
/*
* Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com>
*/
#include <ttm/ttm_module.h>
#include <ttm/ttm_bo_driver.h>
#include <ttm/ttm_placement.h>
#include <linux/mm.h>
#include <linux/rbtree.h>
#include <linux/module.h>
#include <linux/uaccess.h>
#define TTM_BO_VM_NUM_PREFAULT 16
static struct ttm_buffer_object *ttm_bo_vm_lookup_rb(struct ttm_bo_device *bdev,
unsigned long page_start,
unsigned long num_pages)
{
struct rb_node *cur = bdev->addr_space_rb.rb_node;
unsigned long cur_offset;
struct ttm_buffer_object *bo;
struct ttm_buffer_object *best_bo = NULL;
while (likely(cur != NULL)) {
bo = rb_entry(cur, struct ttm_buffer_object, vm_rb);
cur_offset = bo->vm_node->start;
if (page_start >= cur_offset) {
cur = cur->rb_right;
best_bo = bo;
if (page_start == cur_offset)
break;
} else
cur = cur->rb_left;
}
if (unlikely(best_bo == NULL))
return NULL;
if (unlikely((best_bo->vm_node->start + best_bo->num_pages) <
(page_start + num_pages)))
return NULL;
return best_bo;
}
static int ttm_bo_vm_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
{
struct ttm_buffer_object *bo = (struct ttm_buffer_object *)
vma->vm_private_data;
struct ttm_bo_device *bdev = bo->bdev;
unsigned long page_offset;
unsigned long page_last;
unsigned long pfn;
struct ttm_tt *ttm = NULL;
struct page *page;
int ret;
int i;
unsigned long address = (unsigned long)vmf->virtual_address;
int retval = VM_FAULT_NOPAGE;
struct ttm_mem_type_manager *man =
&bdev->man[bo->mem.mem_type];
/*
* Work around locking order reversal in fault / nopfn
* between mmap_sem and bo_reserve: Perform a trylock operation
* for reserve, and if it fails, retry the fault after scheduling.
*/
ret = ttm_bo_reserve(bo, true, true, false, 0);
if (unlikely(ret != 0)) {
if (ret == -EBUSY)
set_need_resched();
return VM_FAULT_NOPAGE;
}
if (bdev->driver->fault_reserve_notify) {
ret = bdev->driver->fault_reserve_notify(bo);
switch (ret) {
case 0:
break;
case -EBUSY:
set_need_resched();
case -ERESTARTSYS:
retval = VM_FAULT_NOPAGE;
goto out_unlock;
default:
retval = VM_FAULT_SIGBUS;
goto out_unlock;
}
}
/*
* Wait for buffer data in transit, due to a pipelined
* move.
*/
spin_lock(&bdev->fence_lock);
if (test_bit(TTM_BO_PRIV_FLAG_MOVING, &bo->priv_flags)) {
ret = ttm_bo_wait(bo, false, true, false);
spin_unlock(&bdev->fence_lock);
if (unlikely(ret != 0)) {
retval = (ret != -ERESTARTSYS) ?
VM_FAULT_SIGBUS : VM_FAULT_NOPAGE;
goto out_unlock;
}
} else
spin_unlock(&bdev->fence_lock);
ret = ttm_mem_io_lock(man, true);
if (unlikely(ret != 0)) {
retval = VM_FAULT_NOPAGE;
goto out_unlock;
}
ret = ttm_mem_io_reserve_vm(bo);
if (unlikely(ret != 0)) {
retval = VM_FAULT_SIGBUS;
goto out_io_unlock;
}
page_offset = ((address - vma->vm_start) >> PAGE_SHIFT) +
bo->vm_node->start - vma->vm_pgoff;
page_last = ((vma->vm_end - vma->vm_start) >> PAGE_SHIFT) +
bo->vm_node->start - vma->vm_pgoff;
if (unlikely(page_offset >= bo->num_pages)) {
retval = VM_FAULT_SIGBUS;
goto out_io_unlock;
}
/*
* Strictly, we're not allowed to modify vma->vm_page_prot here,
* since the mmap_sem is only held in read mode. However, we
* modify only the caching bits of vma->vm_page_prot and
* consider those bits protected by
* the bo->mutex, as we should be the only writers.
* There shouldn't really be any readers of these bits except
* within vm_insert_mixed()? fork?
*
* TODO: Add a list of vmas to the bo, and change the
* vma->vm_page_prot when the object changes caching policy, with
* the correct locks held.
*/
if (bo->mem.bus.is_iomem) {
vma->vm_page_prot = ttm_io_prot(bo->mem.placement,
vma->vm_page_prot);
} else {
ttm = bo->ttm;
vma->vm_page_prot = (bo->mem.placement & TTM_PL_FLAG_CACHED) ?
vm_get_page_prot(vma->vm_flags) :
ttm_io_prot(bo->mem.placement, vma->vm_page_prot);
/* Allocate all page at once, most common usage */
if (ttm->bdev->driver->ttm_tt_populate(ttm)) {
retval = VM_FAULT_OOM;
goto out_io_unlock;
}
}
/*
* Speculatively prefault a number of pages. Only error on
* first page.
*/
for (i = 0; i < TTM_BO_VM_NUM_PREFAULT; ++i) {
if (bo->mem.bus.is_iomem)
pfn = ((bo->mem.bus.base + bo->mem.bus.offset) >> PAGE_SHIFT) + page_offset;
else {
page = ttm->pages[page_offset];
if (unlikely(!page && i == 0)) {
retval = VM_FAULT_OOM;
goto out_io_unlock;
} else if (unlikely(!page)) {
break;
}
pfn = page_to_pfn(page);
}
ret = vm_insert_mixed(vma, address, pfn);
/*
* Somebody beat us to this PTE or prefaulting to
* an already populated PTE, or prefaulting error.
*/
if (unlikely((ret == -EBUSY) || (ret != 0 && i > 0)))
break;
else if (unlikely(ret != 0)) {
retval =
(ret == -ENOMEM) ? VM_FAULT_OOM : VM_FAULT_SIGBUS;
goto out_io_unlock;
}
address += PAGE_SIZE;
if (unlikely(++page_offset >= page_last))
break;
}
out_io_unlock:
ttm_mem_io_unlock(man);
out_unlock:
ttm_bo_unreserve(bo);
return retval;
}
static void ttm_bo_vm_open(struct vm_area_struct *vma)
{
struct ttm_buffer_object *bo =
(struct ttm_buffer_object *)vma->vm_private_data;
(void)ttm_bo_reference(bo);
}
static void ttm_bo_vm_close(struct vm_area_struct *vma)
{
struct ttm_buffer_object *bo = (struct ttm_buffer_object *)vma->vm_private_data;
ttm_bo_unref(&bo);
vma->vm_private_data = NULL;
}
static const struct vm_operations_struct ttm_bo_vm_ops = {
.fault = ttm_bo_vm_fault,
.open = ttm_bo_vm_open,
.close = ttm_bo_vm_close
};
int ttm_bo_mmap(struct file *filp, struct vm_area_struct *vma,
struct ttm_bo_device *bdev)
{
struct ttm_bo_driver *driver;
struct ttm_buffer_object *bo;
int ret;
read_lock(&bdev->vm_lock);
bo = ttm_bo_vm_lookup_rb(bdev, vma->vm_pgoff,
(vma->vm_end - vma->vm_start) >> PAGE_SHIFT);
if (likely(bo != NULL))
ttm_bo_reference(bo);
read_unlock(&bdev->vm_lock);
if (unlikely(bo == NULL)) {
printk(KERN_ERR TTM_PFX
"Could not find buffer object to map.\n");
return -EINVAL;
}
driver = bo->bdev->driver;
if (unlikely(!driver->verify_access)) {
ret = -EPERM;
goto out_unref;
}
ret = driver->verify_access(bo, filp);
if (unlikely(ret != 0))
goto out_unref;
vma->vm_ops = &ttm_bo_vm_ops;
/*
* Note: We're transferring the bo reference to
* vma->vm_private_data here.
*/
vma->vm_private_data = bo;
vma->vm_flags |= VM_RESERVED | VM_IO | VM_MIXEDMAP | VM_DONTEXPAND;
return 0;
out_unref:
ttm_bo_unref(&bo);
return ret;
}
EXPORT_SYMBOL(ttm_bo_mmap);
int ttm_fbdev_mmap(struct vm_area_struct *vma, struct ttm_buffer_object *bo)
{
if (vma->vm_pgoff != 0)
return -EACCES;
vma->vm_ops = &ttm_bo_vm_ops;
vma->vm_private_data = ttm_bo_reference(bo);
vma->vm_flags |= VM_RESERVED | VM_IO | VM_MIXEDMAP | VM_DONTEXPAND;
return 0;
}
EXPORT_SYMBOL(ttm_fbdev_mmap);
ssize_t ttm_bo_io(struct ttm_bo_device *bdev, struct file *filp,
const char __user *wbuf, char __user *rbuf, size_t count,
loff_t *f_pos, bool write)
{
struct ttm_buffer_object *bo;
struct ttm_bo_driver *driver;
struct ttm_bo_kmap_obj map;
unsigned long dev_offset = (*f_pos >> PAGE_SHIFT);
unsigned long kmap_offset;
unsigned long kmap_end;
unsigned long kmap_num;
size_t io_size;
unsigned int page_offset;
char *virtual;
int ret;
bool no_wait = false;
bool dummy;
read_lock(&bdev->vm_lock);
bo = ttm_bo_vm_lookup_rb(bdev, dev_offset, 1);
if (likely(bo != NULL))
ttm_bo_reference(bo);
read_unlock(&bdev->vm_lock);
if (unlikely(bo == NULL))
return -EFAULT;
driver = bo->bdev->driver;
if (unlikely(!driver->verify_access)) {
ret = -EPERM;
goto out_unref;
}
ret = driver->verify_access(bo, filp);
if (unlikely(ret != 0))
goto out_unref;
kmap_offset = dev_offset - bo->vm_node->start;
if (unlikely(kmap_offset >= bo->num_pages)) {
ret = -EFBIG;
goto out_unref;
}
page_offset = *f_pos & ~PAGE_MASK;
io_size = bo->num_pages - kmap_offset;
io_size = (io_size << PAGE_SHIFT) - page_offset;
if (count < io_size)
io_size = count;
kmap_end = (*f_pos + count - 1) >> PAGE_SHIFT;
kmap_num = kmap_end - kmap_offset + 1;
ret = ttm_bo_reserve(bo, true, no_wait, false, 0);
switch (ret) {
case 0:
break;
case -EBUSY:
ret = -EAGAIN;
goto out_unref;
default:
goto out_unref;
}
ret = ttm_bo_kmap(bo, kmap_offset, kmap_num, &map);
if (unlikely(ret != 0)) {
ttm_bo_unreserve(bo);
goto out_unref;
}
virtual = ttm_kmap_obj_virtual(&map, &dummy);
virtual += page_offset;
if (write)
ret = copy_from_user(virtual, wbuf, io_size);
else
ret = copy_to_user(rbuf, virtual, io_size);
ttm_bo_kunmap(&map);
ttm_bo_unreserve(bo);
ttm_bo_unref(&bo);
if (unlikely(ret != 0))
return -EFBIG;
*f_pos += io_size;
return io_size;
out_unref:
ttm_bo_unref(&bo);
return ret;
}
ssize_t ttm_bo_fbdev_io(struct ttm_buffer_object *bo, const char __user *wbuf,
char __user *rbuf, size_t count, loff_t *f_pos,
bool write)
{
struct ttm_bo_kmap_obj map;
unsigned long kmap_offset;
unsigned long kmap_end;
unsigned long kmap_num;
size_t io_size;
unsigned int page_offset;
char *virtual;
int ret;
bool no_wait = false;
bool dummy;
kmap_offset = (*f_pos >> PAGE_SHIFT);
if (unlikely(kmap_offset >= bo->num_pages))
return -EFBIG;
page_offset = *f_pos & ~PAGE_MASK;
io_size = bo->num_pages - kmap_offset;
io_size = (io_size << PAGE_SHIFT) - page_offset;
if (count < io_size)
io_size = count;
kmap_end = (*f_pos + count - 1) >> PAGE_SHIFT;
kmap_num = kmap_end - kmap_offset + 1;
ret = ttm_bo_reserve(bo, true, no_wait, false, 0);
switch (ret) {
case 0:
break;
case -EBUSY:
return -EAGAIN;
default:
return ret;
}
ret = ttm_bo_kmap(bo, kmap_offset, kmap_num, &map);
if (unlikely(ret != 0)) {
ttm_bo_unreserve(bo);
return ret;
}
virtual = ttm_kmap_obj_virtual(&map, &dummy);
virtual += page_offset;
if (write)
ret = copy_from_user(virtual, wbuf, io_size);
else
ret = copy_to_user(rbuf, virtual, io_size);
ttm_bo_kunmap(&map);
ttm_bo_unreserve(bo);
ttm_bo_unref(&bo);
if (unlikely(ret != 0))
return ret;
*f_pos += io_size;
return io_size;
}