Commit 4f7e89f6 authored by Yan, Zheng's avatar Yan, Zheng Committed by Ilya Dryomov
Browse files

ceph: block non-fatal signals for fault/page_mkwrite 



Fault and page_mkwrite are supposed to be uninterruptable. But they
call ceph functions that are interruptible. So they should block
signals before calling functions that are interruptible

Signed-off-by: default avatarYan, Zheng <zyan@redhat.com>
parent 3b33f692

fs/ceph/addr.c

+39 −27
Original line number Diff line number Diff line
@@ -1315,6 +1315,17 @@ const struct address_space_operations ceph_aops = { 
	.direct_IO = ceph_direct_io,

};



static void ceph_block_sigs(sigset_t *oldset)

{

	sigset_t mask;

	siginitsetinv(&mask, sigmask(SIGKILL));

	sigprocmask(SIG_BLOCK, &mask, oldset);

}



static void ceph_restore_sigs(sigset_t *oldset)

{

	sigprocmask(SIG_SETMASK, oldset, NULL);

}



/*

 * vm ops
@@ -1327,6 +1338,9 @@ static int ceph_filemap_fault(struct vm_area_struct *vma, struct vm_fault *vmf) 
	struct page *pinned_page = NULL;

	loff_t off = vmf->pgoff << PAGE_SHIFT;

	int want, got, ret;

	sigset_t oldset;



	ceph_block_sigs(&oldset);



	dout("filemap_fault %p %llx.%llx %llu~%zd trying to get caps\n",

	     inode, ceph_vinop(inode), off, (size_t)PAGE_SIZE);
@@ -1334,16 +1348,12 @@ static int ceph_filemap_fault(struct vm_area_struct *vma, struct vm_fault *vmf) 
		want = CEPH_CAP_FILE_CACHE | CEPH_CAP_FILE_LAZYIO;

	else

		want = CEPH_CAP_FILE_CACHE;

	while (1) {



	got = 0;

		ret = ceph_get_caps(ci, CEPH_CAP_FILE_RD, want,

				    -1, &got, &pinned_page);

		if (ret == 0)

			break;

		if (ret != -ERESTARTSYS) {

			WARN_ON(1);

			return VM_FAULT_SIGBUS;

		}

	ret = ceph_get_caps(ci, CEPH_CAP_FILE_RD, want, -1, &got, &pinned_page);

	if (ret < 0) {

		ret = VM_FAULT_SIGBUS;

		goto out_restore;

	}

	dout("filemap_fault %p %llu~%zd got cap refs on %s\n",

	     inode, off, (size_t)PAGE_SIZE, ceph_cap_string(got));
@@ -1361,7 +1371,7 @@ static int ceph_filemap_fault(struct vm_area_struct *vma, struct vm_fault *vmf) 
	ceph_put_cap_refs(ci, got);



	if (ret != -EAGAIN)

		return ret;

		goto out_restore;



	/* read inline data */

	if (off >= PAGE_SIZE) {
@@ -1375,7 +1385,7 @@ static int ceph_filemap_fault(struct vm_area_struct *vma, struct vm_fault *vmf) 
						~__GFP_FS));

		if (!page) {

			ret = VM_FAULT_OOM;

			goto out;

			goto out_inline;

		}

		ret1 = __ceph_do_getattr(inode, page,

					 CEPH_STAT_CAP_INLINE_DATA, true);
@@ -1383,7 +1393,7 @@ static int ceph_filemap_fault(struct vm_area_struct *vma, struct vm_fault *vmf) 
			unlock_page(page);

			put_page(page);

			ret = VM_FAULT_SIGBUS;

			goto out;

			goto out_inline;

		}

		if (ret1 < PAGE_SIZE)

			zero_user_segment(page, ret1, PAGE_SIZE);
@@ -1392,10 +1402,12 @@ static int ceph_filemap_fault(struct vm_area_struct *vma, struct vm_fault *vmf) 
		SetPageUptodate(page);

		vmf->page = page;

		ret = VM_FAULT_MAJOR | VM_FAULT_LOCKED;

	}

out:

out_inline:

		dout("filemap_fault %p %llu~%zd read inline data ret %d\n",

		     inode, off, (size_t)PAGE_SIZE, ret);

	}

out_restore:

	ceph_restore_sigs(&oldset);

	return ret;

}
@@ -1413,11 +1425,14 @@ static int ceph_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf) 
	loff_t size = i_size_read(inode);

	size_t len;

	int want, got, ret;

	sigset_t oldset;



	prealloc_cf = ceph_alloc_cap_flush();

	if (!prealloc_cf)

		return VM_FAULT_SIGBUS;



	ceph_block_sigs(&oldset);



	if (ci->i_inline_version != CEPH_INLINE_NONE) {

		struct page *locked_page = NULL;

		if (off == 0) {
@@ -1444,18 +1459,14 @@ static int ceph_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf) 
		want = CEPH_CAP_FILE_BUFFER | CEPH_CAP_FILE_LAZYIO;

	else

		want = CEPH_CAP_FILE_BUFFER;

	while (1) {



	got = 0;

	ret = ceph_get_caps(ci, CEPH_CAP_FILE_WR, want, off + len,

			    &got, NULL);

		if (ret == 0)

			break;

		if (ret != -ERESTARTSYS) {

			WARN_ON(1);

	if (ret < 0) {

		ret = VM_FAULT_SIGBUS;

		goto out_free;

	}

	}

	dout("page_mkwrite %p %llu~%zd got cap refs on %s\n",

	     inode, off, len, ceph_cap_string(got));
@@ -1499,6 +1510,7 @@ out: 
	     inode, off, len, ceph_cap_string(got), ret);

	ceph_put_cap_refs(ci, got);

out_free:

	ceph_restore_sigs(&oldset);

	ceph_free_cap_flush(prealloc_cf);



	return ret;