orangefs: implement vm_ops->fault
Must retrieve size before running filemap_fault so the kernel has
an up-to-date size.
This should have been caught by xfstests generic/246, but it was masked
by orangefs_new_inode, which set i_size to PAGE_SIZE. When nothing
caused a getattr prior to a pagefault, i_size was still PAGE_SIZE.
Since xfstests only read 10 bytes, it did not catch this bug.
When orangefs_new_inode was modified to perform a getattr instead,
i_size was set to zero, as it was a newly created file. Then
orangefs_file_write_iter did NOT set i_size. Instead it invalidated the
attribute cache, which should have caused the next caller to retrieve
i_size. But the fault handler did not know it was supposed to retrieve
i_size. So during xfstests, i_size was still zero, and filemap_fault
returned VM_FAULT_SIGBUS.
Fixes xfstests generic/452.
Signed-off-by: Martin Brandenburg <martin@omnibond.com>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
diff --git a/fs/orangefs/file.c b/fs/orangefs/file.c
index 3a7319a..26358ef 100644
--- a/fs/orangefs/file.c
+++ b/fs/orangefs/file.c
@@ -528,6 +528,28 @@ static long orangefs_ioctl(struct file *file, unsigned int cmd, unsigned long ar
return ret;
}
+static int orangefs_fault(struct vm_fault *vmf)
+{
+ struct file *file = vmf->vma->vm_file;
+ int rc;
+ rc = orangefs_inode_getattr(file->f_mapping->host, 0, 1,
+ STATX_SIZE);
+ if (rc == -ESTALE)
+ rc = -EIO;
+ if (rc) {
+ gossip_err("%s: orangefs_inode_getattr failed, "
+ "rc:%d:.\n", __func__, rc);
+ return rc;
+ }
+ return filemap_fault(vmf);
+}
+
+const struct vm_operations_struct orangefs_file_vm_ops = {
+ .fault = orangefs_fault,
+ .map_pages = filemap_map_pages,
+ .page_mkwrite = filemap_page_mkwrite,
+};
+
/*
* Memory map a region of a file.
*/
@@ -539,12 +561,16 @@ static int orangefs_file_mmap(struct file *file, struct vm_area_struct *vma)
(char *)file->f_path.dentry->d_name.name :
(char *)"Unknown"));
+ if ((vma->vm_flags & VM_SHARED) && (vma->vm_flags & VM_MAYWRITE))
+ return -EINVAL;
+
/* set the sequential readahead hint */
vma->vm_flags |= VM_SEQ_READ;
vma->vm_flags &= ~VM_RAND_READ;
- /* Use readonly mmap since we cannot support writable maps. */
- return generic_file_readonly_mmap(file, vma);
+ file_accessed(file);
+ vma->vm_ops = &orangefs_file_vm_ops;
+ return 0;
}
#define mapping_nrpages(idata) ((idata)->nrpages)
