1 files changed, 24 insertions, 26 deletions

diff --git a/fs/fuse/dax.c b/fs/fuse/dax.c
index 9d58371d22c2..281d79f8b3d3 100644
--- a/fs/fuse/dax.c
+++ b/fs/fuse/dax.c
@@ -444,12 +444,12 @@ static int fuse_setup_new_dax_mapping(struct inode *inode, loff_t pos,
 	/*
 	 * Can't do inline reclaim in fault path. We call
 	 * dax_layout_busy_page() before we free a range. And
-	 * fuse_wait_dax_page() drops fi->i_mmap_sem lock and requires it.
-	 * In fault path we enter with fi->i_mmap_sem held and can't drop
-	 * it. Also in fault path we hold fi->i_mmap_sem shared and not
-	 * exclusive, so that creates further issues with fuse_wait_dax_page().
-	 * Hence return -EAGAIN and fuse_dax_fault() will wait for a memory
-	 * range to become free and retry.
+	 * fuse_wait_dax_page() drops mapping->invalidate_lock and requires it.
+	 * In fault path we enter with mapping->invalidate_lock held and can't
+	 * drop it. Also in fault path we hold mapping->invalidate_lock shared
+	 * and not exclusive, so that creates further issues with
+	 * fuse_wait_dax_page().  Hence return -EAGAIN and fuse_dax_fault()
+	 * will wait for a memory range to become free and retry.
 	 */
 	if (flags & IOMAP_FAULT) {
 		alloc_dmap = alloc_dax_mapping(fcd);
@@ -513,7 +513,7 @@ static int fuse_upgrade_dax_mapping(struct inode *inode, loff_t pos,
 	down_write(&fi->dax->sem);
 	node = interval_tree_iter_first(&fi->dax->tree, idx, idx);
 
-	/* We are holding either inode lock or i_mmap_sem, and that should
+	/* We are holding either inode lock or invalidate_lock, and that should
 	 * ensure that dmap can't be truncated. We are holding a reference
 	 * on dmap and that should make sure it can't be reclaimed. So dmap
 	 * should still be there in tree despite the fact we dropped and
@@ -660,14 +660,12 @@ static const struct iomap_ops fuse_iomap_ops = {
 
 static void fuse_wait_dax_page(struct inode *inode)
 {
-	struct fuse_inode *fi = get_fuse_inode(inode);
-
-	up_write(&fi->i_mmap_sem);
+	filemap_invalidate_unlock(inode->i_mapping);
 	schedule();
-	down_write(&fi->i_mmap_sem);
+	filemap_invalidate_lock(inode->i_mapping);
 }
 
-/* Should be called with fi->i_mmap_sem lock held exclusively */
+/* Should be called with mapping->invalidate_lock held exclusively */
 static int __fuse_dax_break_layouts(struct inode *inode, bool *retry,
 				    loff_t start, loff_t end)
 {
@@ -813,18 +811,18 @@ retry:
 	 * we do not want any read/write/mmap to make progress and try
 	 * to populate page cache or access memory we are trying to free.
 	 */
-	down_read(&get_fuse_inode(inode)->i_mmap_sem);
+	filemap_invalidate_lock_shared(inode->i_mapping);
 	ret = dax_iomap_fault(vmf, pe_size, &pfn, &error, &fuse_iomap_ops);
 	if ((ret & VM_FAULT_ERROR) && error == -EAGAIN) {
 		error = 0;
 		retry = true;
-		up_read(&get_fuse_inode(inode)->i_mmap_sem);
+		filemap_invalidate_unlock_shared(inode->i_mapping);
 		goto retry;
 	}
 
 	if (ret & VM_FAULT_NEEDDSYNC)
 		ret = dax_finish_sync_fault(vmf, pe_size, pfn);
-	up_read(&get_fuse_inode(inode)->i_mmap_sem);
+	filemap_invalidate_unlock_shared(inode->i_mapping);
 
 	if (write)
 		sb_end_pagefault(sb);
@@ -960,7 +958,7 @@ inode_inline_reclaim_one_dmap(struct fuse_conn_dax *fcd, struct inode *inode,
 	int ret;
 	struct interval_tree_node *node;
 
-	down_write(&fi->i_mmap_sem);
+	filemap_invalidate_lock(inode->i_mapping);
 
 	/* Lookup a dmap and corresponding file offset to reclaim. */
 	down_read(&fi->dax->sem);
@@ -1021,7 +1019,7 @@ inode_inline_reclaim_one_dmap(struct fuse_conn_dax *fcd, struct inode *inode,
 out_write_dmap_sem:
 	up_write(&fi->dax->sem);
 out_mmap_sem:
-	up_write(&fi->i_mmap_sem);
+	filemap_invalidate_unlock(inode->i_mapping);
 	return dmap;
 }
 
@@ -1050,10 +1048,10 @@ alloc_dax_mapping_reclaim(struct fuse_conn_dax *fcd, struct inode *inode)
 		 * had a reference or some other temporary failure,
 		 * Try again. We want to give up inline reclaim only
 		 * if there is no range assigned to this node. Otherwise
-		 * if a deadlock is possible if we sleep with fi->i_mmap_sem
-		 * held and worker to free memory can't make progress due
-		 * to unavailability of fi->i_mmap_sem lock. So sleep
-		 * only if fi->dax->nr=0
+		 * if a deadlock is possible if we sleep with
+		 * mapping->invalidate_lock held and worker to free memory
+		 * can't make progress due to unavailability of
+		 * mapping->invalidate_lock.  So sleep only if fi->dax->nr=0
 		 */
 		if (retry)
 			continue;
@@ -1061,8 +1059,8 @@ alloc_dax_mapping_reclaim(struct fuse_conn_dax *fcd, struct inode *inode)
 		 * There are no mappings which can be reclaimed. Wait for one.
 		 * We are not holding fi->dax->sem. So it is possible
 		 * that range gets added now. But as we are not holding
-		 * fi->i_mmap_sem, worker should still be able to free up
-		 * a range and wake us up.
+		 * mapping->invalidate_lock, worker should still be able to
+		 * free up a range and wake us up.
 		 */
 		if (!fi->dax->nr && !(fcd->nr_free_ranges > 0)) {
 			if (wait_event_killable_exclusive(fcd->range_waitq,
@@ -1108,7 +1106,7 @@ static int lookup_and_reclaim_dmap_locked(struct fuse_conn_dax *fcd,
 /*
  * Free a range of memory.
  * Locking:
- * 1. Take fi->i_mmap_sem to block dax faults.
+ * 1. Take mapping->invalidate_lock to block dax faults.
  * 2. Take fi->dax->sem to protect interval tree and also to make sure
  *    read/write can not reuse a dmap which we might be freeing.
  */
@@ -1122,7 +1120,7 @@ static int lookup_and_reclaim_dmap(struct fuse_conn_dax *fcd,
 	loff_t dmap_start = start_idx << FUSE_DAX_SHIFT;
 	loff_t dmap_end = (dmap_start + FUSE_DAX_SZ) - 1;
 
-	down_write(&fi->i_mmap_sem);
+	filemap_invalidate_lock(inode->i_mapping);
 	ret = fuse_dax_break_layouts(inode, dmap_start, dmap_end);
 	if (ret) {
 		pr_debug("virtio_fs: fuse_dax_break_layouts() failed. err=%d\n",
@@ -1134,7 +1132,7 @@ static int lookup_and_reclaim_dmap(struct fuse_conn_dax *fcd,
 	ret = lookup_and_reclaim_dmap_locked(fcd, inode, start_idx);
 	up_write(&fi->dax->sem);
 out_mmap_sem:
-	up_write(&fi->i_mmap_sem);
+	filemap_invalidate_unlock(inode->i_mapping);
 	return ret;
 }