#endif /* CONFIG_HAVE_RCU_TABLE_FREE */
-/* tlb_gather_mmu
- * Called to initialize an (on-stack) mmu_gather structure for page-table
- * tear-down from @mm. The @fullmm argument is used when @mm is without
- * users and we're going to destroy the full address space (exit/execve).
+/**
+ * tlb_gather_mmu - initialize an mmu_gather structure for page-table tear-down
+ * @tlb: the mmu_gather structure to initialize
+ * @mm: the mm_struct of the target address space
+ * @start: start of the region that will be removed from the page-table
+ * @end: end of the region that will be removed from the page-table
+ *
+ * Called to initialize an (on-stack) mmu_gather structure for page-table
+ * tear-down from @mm. The @start and @end are set to 0 and -1
+ * respectively when @mm is without users and we're going to destroy
+ * the full address space (exit/execve).
*/
void tlb_gather_mmu(struct mmu_gather *tlb, struct mm_struct *mm,
unsigned long start, unsigned long end)
}
EXPORT_SYMBOL(vm_insert_pfn_prot);
+static bool vm_mixed_ok(struct vm_area_struct *vma, pfn_t pfn)
+{
+ /* these checks mirror the abort conditions in vm_normal_page */
+ if (vma->vm_flags & VM_MIXEDMAP)
+ return true;
+ if (pfn_t_devmap(pfn))
+ return true;
+ if (pfn_t_special(pfn))
+ return true;
+ if (is_zero_pfn(pfn_t_to_pfn(pfn)))
+ return true;
+ return false;
+}
+
static int __vm_insert_mixed(struct vm_area_struct *vma, unsigned long addr,
pfn_t pfn, bool mkwrite)
{
pgprot_t pgprot = vma->vm_page_prot;
- BUG_ON(!(vma->vm_flags & VM_MIXEDMAP));
+ BUG_ON(!vm_mixed_ok(vma, pfn));
if (addr < vma->vm_start || addr >= vma->vm_end)
return -EFAULT;
}
}
+/**
+ * unmap_mapping_pages() - Unmap pages from processes.
+ * @mapping: The address space containing pages to be unmapped.
+ * @start: Index of first page to be unmapped.
+ * @nr: Number of pages to be unmapped. 0 to unmap to end of file.
+ * @even_cows: Whether to unmap even private COWed pages.
+ *
+ * Unmap the pages in this address space from any userspace process which
+ * has them mmaped. Generally, you want to remove COWed pages as well when
+ * a file is being truncated, but not when invalidating pages from the page
+ * cache.
+ */
+void unmap_mapping_pages(struct address_space *mapping, pgoff_t start,
+ pgoff_t nr, bool even_cows)
+{
+ struct zap_details details = { };
+
+ details.check_mapping = even_cows ? NULL : mapping;
+ details.first_index = start;
+ details.last_index = start + nr - 1;
+ if (details.last_index < details.first_index)
+ details.last_index = ULONG_MAX;
+
+ i_mmap_lock_write(mapping);
+ if (unlikely(!RB_EMPTY_ROOT(&mapping->i_mmap.rb_root)))
+ unmap_mapping_range_tree(&mapping->i_mmap, &details);
+ i_mmap_unlock_write(mapping);
+}
+
/**
* unmap_mapping_range - unmap the portion of all mmaps in the specified
- * address_space corresponding to the specified page range in the underlying
+ * address_space corresponding to the specified byte range in the underlying
* file.
*
* @mapping: the address space containing mmaps to be unmapped.
void unmap_mapping_range(struct address_space *mapping,
loff_t const holebegin, loff_t const holelen, int even_cows)
{
- struct zap_details details = { };
pgoff_t hba = holebegin >> PAGE_SHIFT;
pgoff_t hlen = (holelen + PAGE_SIZE - 1) >> PAGE_SHIFT;
hlen = ULONG_MAX - hba + 1;
}
- details.check_mapping = even_cows ? NULL : mapping;
- details.first_index = hba;
- details.last_index = hba + hlen - 1;
- if (details.last_index < details.first_index)
- details.last_index = ULONG_MAX;
-
- i_mmap_lock_write(mapping);
- if (unlikely(!RB_EMPTY_ROOT(&mapping->i_mmap.rb_root)))
- unmap_mapping_range_tree(&mapping->i_mmap, &details);
- i_mmap_unlock_write(mapping);
+ unmap_mapping_pages(mapping, hba, hlen, even_cows);
}
EXPORT_SYMBOL(unmap_mapping_range);
}
/*
- * fault_around_pages() and fault_around_mask() expects fault_around_bytes
- * rounded down to nearest page order. It's what do_fault_around() expects to
- * see.
+ * fault_around_bytes must be rounded down to the nearest page order as it's
+ * what do_fault_around() expects to see.
*/
static int fault_around_bytes_set(void *data, u64 val)
{
* This function doesn't cross the VMA boundaries, in order to call map_pages()
* only once.
*
- * fault_around_pages() defines how many pages we'll try to map.
- * do_fault_around() expects it to return a power of two less than or equal to
- * PTRS_PER_PTE.
+ * fault_around_bytes defines how many bytes we'll try to map.
+ * do_fault_around() expects it to be set to a power of two less than or equal
+ * to PTRS_PER_PTE.
*
- * The virtual address of the area that we map is naturally aligned to the
- * fault_around_pages() value (and therefore to page order). This way it's
- * easier to guarantee that we don't cross page table boundaries.
+ * The virtual address of the area that we map is naturally aligned to
+ * fault_around_bytes rounded down to the machine page size
+ * (and therefore to page order). This way it's easier to guarantee
+ * that we don't cross page table boundaries.
*/
static int do_fault_around(struct vm_fault *vmf)
{
start_pgoff -= off;
/*
- * end_pgoff is either end of page table or end of vma
- * or fault_around_pages() from start_pgoff, depending what is nearest.
+ * end_pgoff is either the end of the page table, the end of
+ * the vma or nr_pages from start_pgoff, depending what is nearest.
*/
end_pgoff = start_pgoff -
((vmf->address >> PAGE_SHIFT) & (PTRS_PER_PTE - 1)) +
projects / linux-2.6-microblaze.git / blobdiff