mm: merge hmm_vma_do_fault into into hmm_vma_walk_hole_

There is no good reason for this split, as it just obsfucates the flow.

Link: https://lore.kernel.org/r/20200316135310.899364-6-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

diff --git a/mm/hmm.c b/mm/hmm.c
index b15bf40418033732589517517511fb2b31b07274..a5f4f80109656901003daceed0ad89fd23b82535 100644 (file)
--- a/mm/hmm.c
+++ b/mm/hmm.c
@@ -33,32 +33,6 @@ struct hmm_vma_walk {
        unsigned int            flags;
 };
 
-static int hmm_vma_do_fault(struct mm_walk *walk, unsigned long addr,
-                           bool write_fault, uint64_t *pfn)
-{
-       unsigned int flags = FAULT_FLAG_REMOTE;
-       struct hmm_vma_walk *hmm_vma_walk = walk->private;
-       struct hmm_range *range = hmm_vma_walk->range;
-       struct vm_area_struct *vma = walk->vma;
-       vm_fault_t ret;
-
-       if (!vma)
-               goto err;
-
-       if (write_fault)
-               flags |= FAULT_FLAG_WRITE;
-
-       ret = handle_mm_fault(vma, addr, flags);
-       if (ret & VM_FAULT_ERROR)
-               goto err;
-
-       return -EBUSY;
-
-err:
-       *pfn = range->values[HMM_PFN_ERROR];
-       return -EFAULT;
-}
-
 static int hmm_pfns_fill(unsigned long addr, unsigned long end,
                struct hmm_range *range, enum hmm_pfn_value_e value)
 {
@@ -90,24 +64,32 @@ static int hmm_vma_fault(unsigned long addr, unsigned long end,
 {
        struct hmm_vma_walk *hmm_vma_walk = walk->private;
        struct hmm_range *range = hmm_vma_walk->range;
+       struct vm_area_struct *vma = walk->vma;
        uint64_t *pfns = range->pfns;
        unsigned long i = (addr - range->start) >> PAGE_SHIFT;
+       unsigned int fault_flags = FAULT_FLAG_REMOTE;
 
        WARN_ON_ONCE(!fault && !write_fault);
        hmm_vma_walk->last = addr;
 
-       if (write_fault && walk->vma && !(walk->vma->vm_flags & VM_WRITE))
-               return -EPERM;
-
-       for (; addr < end; addr += PAGE_SIZE, i++) {
-               int ret;
+       if (!vma)
+               goto out_error;
 
-               ret = hmm_vma_do_fault(walk, addr, write_fault, &pfns[i]);
-               if (ret != -EBUSY)
-                       return ret;
+       if (write_fault) {
+               if (!(vma->vm_flags & VM_WRITE))
+                       return -EPERM;
+               fault_flags |= FAULT_FLAG_WRITE;
        }
 
+       for (; addr < end; addr += PAGE_SIZE, i++)
+               if (handle_mm_fault(vma, addr, fault_flags) & VM_FAULT_ERROR)
+                       goto out_error;
+
        return -EBUSY;
+
+out_error:
+       pfns[i] = range->values[HMM_PFN_ERROR];
+       return -EFAULT;
 }
 
 static inline void hmm_pte_need_fault(const struct hmm_vma_walk *hmm_vma_walk,