This reverts commit f649e63d4a6423eda8eb208638849fd6396aedd7.

The read-only feature requires further consideration.

Signed-off-by: Lizhi Hou <[email protected]>
---
 drivers/accel/amdxdna/amdxdna_ubuf.c | 29 ++--------------------------
 1 file changed, 2 insertions(+), 27 deletions(-)

diff --git a/drivers/accel/amdxdna/amdxdna_ubuf.c 
b/drivers/accel/amdxdna/amdxdna_ubuf.c
index 3769210c55cc..4c0647057759 100644
--- a/drivers/accel/amdxdna/amdxdna_ubuf.c
+++ b/drivers/accel/amdxdna/amdxdna_ubuf.c
@@ -125,26 +125,6 @@ static const struct dma_buf_ops amdxdna_ubuf_dmabuf_ops = {
        .vunmap = amdxdna_ubuf_vunmap,
 };
 
-static int readonly_va_entry(struct amdxdna_drm_va_entry *va_ent)
-{
-       struct mm_struct *mm = current->mm;
-       struct vm_area_struct *vma;
-       int ret;
-
-       mmap_read_lock(mm);
-
-       vma = find_vma(mm, va_ent->vaddr);
-       if (!vma ||
-           vma->vm_start > va_ent->vaddr ||
-           vma->vm_end - va_ent->vaddr < va_ent->len)
-               ret = -ENOENT;
-       else
-               ret = vma->vm_flags & VM_WRITE ? 0 : 1;
-
-       mmap_read_unlock(mm);
-       return ret;
-}
-
 struct dma_buf *amdxdna_get_ubuf(struct drm_device *dev,
                                 u32 num_entries, void __user *va_entries)
 {
@@ -154,7 +134,6 @@ struct dma_buf *amdxdna_get_ubuf(struct drm_device *dev,
        struct amdxdna_ubuf_priv *ubuf;
        u32 npages, start = 0;
        struct dma_buf *dbuf;
-       bool readonly = true;
        int i, ret;
        DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
 
@@ -193,10 +172,6 @@ struct dma_buf *amdxdna_get_ubuf(struct drm_device *dev,
                        ret = -EINVAL;
                        goto free_ent;
                }
-
-               /* Pin pages as writable as long as not all entries are 
read-only. */
-               if (readonly && readonly_va_entry(&va_ent[i]) != 1)
-                       readonly = false;
        }
 
        ubuf->nr_pages = exp_info.size >> PAGE_SHIFT;
@@ -219,7 +194,7 @@ struct dma_buf *amdxdna_get_ubuf(struct drm_device *dev,
                npages = va_ent[i].len >> PAGE_SHIFT;
 
                ret = pin_user_pages_fast(va_ent[i].vaddr, npages,
-                                         (readonly ? 0 : FOLL_WRITE) | 
FOLL_LONGTERM,
+                                         FOLL_WRITE | FOLL_LONGTERM,
                                          &ubuf->pages[start]);
                if (ret >= 0) {
                        start += ret;
@@ -236,7 +211,7 @@ struct dma_buf *amdxdna_get_ubuf(struct drm_device *dev,
 
        exp_info.ops = &amdxdna_ubuf_dmabuf_ops;
        exp_info.priv = ubuf;
-       exp_info.flags = (readonly ? O_RDONLY : O_RDWR) | O_CLOEXEC;
+       exp_info.flags = O_RDWR | O_CLOEXEC;
 
        dbuf = dma_buf_export(&exp_info);
        if (IS_ERR(dbuf)) {
-- 
2.34.1

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