return 1;
}
+ if (tlb->batch_count == MAX_GATHER_BATCH_COUNT)
+ return 0;
+
batch = (void *)__get_free_pages(GFP_NOWAIT | __GFP_NOWARN, 0);
if (!batch)
return 0;
+ tlb->batch_count++;
batch->next = NULL;
batch->nr = 0;
batch->max = MAX_GATHER_BATCH;
tlb->local.nr = 0;
tlb->local.max = ARRAY_SIZE(tlb->__pages);
tlb->active = &tlb->local;
+ tlb->batch_count = 0;
#ifdef CONFIG_HAVE_RCU_TABLE_FREE
tlb->batch = NULL;
}
EXPORT_SYMBOL(remap_pfn_range);
+/**
+ * vm_iomap_memory - remap memory to userspace
+ * @vma: user vma to map to
+ * @start: start of area
+ * @len: size of area
+ *
+ * This is a simplified io_remap_pfn_range() for common driver use. The
+ * driver just needs to give us the physical memory range to be mapped,
+ * we'll figure out the rest from the vma information.
+ *
+ * NOTE! Some drivers might want to tweak vma->vm_page_prot first to get
+ * whatever write-combining details or similar.
+ */
+int vm_iomap_memory(struct vm_area_struct *vma, phys_addr_t start, unsigned long len)
+{
+ unsigned long vm_len, pfn, pages;
+
+ /* Check that the physical memory area passed in looks valid */
+ if (start + len < start)
+ return -EINVAL;
+ /*
+ * You *really* shouldn't map things that aren't page-aligned,
+ * but we've historically allowed it because IO memory might
+ * just have smaller alignment.
+ */
+ len += start & ~PAGE_MASK;
+ pfn = start >> PAGE_SHIFT;
+ pages = (len + ~PAGE_MASK) >> PAGE_SHIFT;
+ if (pfn + pages < pfn)
+ return -EINVAL;
+
+ /* We start the mapping 'vm_pgoff' pages into the area */
+ if (vma->vm_pgoff > pages)
+ return -EINVAL;
+ pfn += vma->vm_pgoff;
+ pages -= vma->vm_pgoff;
+
+ /* Can we fit all of the mapping? */
+ vm_len = vma->vm_end - vma->vm_start;
+ if (vm_len >> PAGE_SHIFT > pages)
+ return -EINVAL;
+
+ /* Ok, let it rip */
+ return io_remap_pfn_range(vma, vma->vm_start, pfn, vm_len, vma->vm_page_prot);
+}
+EXPORT_SYMBOL(vm_iomap_memory);
+
static int apply_to_pte_range(struct mm_struct *mm, pmd_t *pmd,
unsigned long addr, unsigned long end,
pte_fn_t fn, void *data)
if (unlikely(is_vm_hugetlb_page(vma)))
return hugetlb_fault(mm, vma, address, flags);
+retry:
pgd = pgd_offset(mm, address);
pud = pud_alloc(mm, pgd, address);
if (!pud)
pmd, flags);
} else {
pmd_t orig_pmd = *pmd;
+ int ret;
+
barrier();
if (pmd_trans_huge(orig_pmd)) {
- if (flags & FAULT_FLAG_WRITE &&
- !pmd_write(orig_pmd) &&
- !pmd_trans_splitting(orig_pmd))
- return do_huge_pmd_wp_page(mm, vma, address,
- pmd, orig_pmd);
+ unsigned int dirty = flags & FAULT_FLAG_WRITE;
+
+ if (dirty && !pmd_write(orig_pmd) &&
+ !pmd_trans_splitting(orig_pmd)) {
+ ret = do_huge_pmd_wp_page(mm, vma, address, pmd,
+ orig_pmd);
+ /*
+ * If COW results in an oom, the huge pmd will
+ * have been split, so retry the fault on the
+ * pte for a smaller charge.
+ */
+ if (unlikely(ret & VM_FAULT_OOM))
+ goto retry;
+ return ret;
+ } else {
+ huge_pmd_set_accessed(mm, vma, address, pmd,
+ orig_pmd, dirty);
+ }
return 0;
}
}