ceph: don't call ceph_update_writeable_page from page_mkwrite

page_mkwrite should only be called with Uptodate pages, so we should
only need to flush incompatible snap contexts.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c
index f8b478237ea8a939755fc0b79544ff443698f47e..c2c23b468d13528280d5eba9a7a95c63b7980a8d 100644 (file)
--- a/fs/ceph/addr.c
+++ b/fs/ceph/addr.c
@@ -1300,7 +1300,6 @@ static int context_is_writeable_or_written(struct inode *inode,
 
 /**
  * ceph_find_incompatible - find an incompatible context and return it
- * @inode: inode associated with page
  * @page: page being dirtied
  *
  * We are only allowed to write into/dirty a page if the page is
@@ -1311,8 +1310,9 @@ static int context_is_writeable_or_written(struct inode *inode,
  * Must be called with page lock held.
  */
 static struct ceph_snap_context *
-ceph_find_incompatible(struct inode *inode, struct page *page)
+ceph_find_incompatible(struct page *page)
 {
+       struct inode *inode = page->mapping->host;
        struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
        struct ceph_inode_info *ci = ceph_inode(inode);
 
@@ -1376,7 +1376,7 @@ static int ceph_update_writeable_page(struct file *file,
        int r;
 
 retry_locked:
-       snapc = ceph_find_incompatible(inode, page);
+       snapc = ceph_find_incompatible(page);
        if (snapc) {
                if (IS_ERR(snapc)) {
                        r = PTR_ERR(snapc);
@@ -1689,6 +1689,8 @@ static vm_fault_t ceph_page_mkwrite(struct vm_fault *vmf)
        inode_inc_iversion_raw(inode);
 
        do {
+               struct ceph_snap_context *snapc;
+
                lock_page(page);
 
                if (page_mkwrite_check_truncate(page, inode) < 0) {
@@ -1697,13 +1699,26 @@ static vm_fault_t ceph_page_mkwrite(struct vm_fault *vmf)
                        break;
                }
 
-               err = ceph_update_writeable_page(vma->vm_file, off, len, page);
-               if (err >= 0) {
+               snapc = ceph_find_incompatible(page);
+               if (!snapc) {
                        /* success.  we'll keep the page locked. */
                        set_page_dirty(page);
                        ret = VM_FAULT_LOCKED;
+                       break;
+               }
+
+               unlock_page(page);
+
+               if (IS_ERR(snapc)) {
+                       ret = VM_FAULT_SIGBUS;
+                       break;
                }
-       } while (err == -EAGAIN);
+
+               ceph_queue_writeback(inode);
+               err = wait_event_killable(ci->i_cap_wq,
+                               context_is_writeable_or_written(inode, snapc));
+               ceph_put_snap_context(snapc);
+       } while (err == 0);
 
        if (ret == VM_FAULT_LOCKED ||
            ci->i_inline_version != CEPH_INLINE_NONE) {