1 files changed, 465 insertions, 0 deletions
diff --git a/drivers/gpu/drm/ttm/ttm_bo_vm.c b/drivers/gpu/drm/ttm/ttm_bo_vm.c
new file mode 100644
index 0000000..3df9f16
--- /dev/null
+++ b/drivers/gpu/drm/ttm/ttm_bo_vm.c
@@ -0,0 +1,465 @@
+/**************************************************************************
+ *
+ * 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>
+ */
+
+#define pr_fmt(fmt) "[TTM] " fmt
+
+#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_pages(vma) +
+	    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_pages(vma));
+	if (likely(bo != NULL) && !kref_get_unless_zero(&bo->kref))
+		bo = NULL;
+	read_unlock(&bdev->vm_lock);
+
+	if (unlikely(bo == NULL)) {
+		pr_err("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_IO | VM_MIXEDMAP | VM_DONTEXPAND | VM_DONTDUMP;
+	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_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;
+}