pNFS: Handle RPC size limit for layoutcommits

[ Upstream commit d897d81 ]

When there are too many block extents for a layoutcommit, they may not
all fit into the maximum-sized RPC. This patch allows the generic pnfs
code to properly handle -ENOSPC returned by the block/scsi layout driver
and trigger additional layoutcommits if necessary.

Co-developed-by: Konstantin Evtushenko <koevtushenko@yandex.com>
Signed-off-by: Konstantin Evtushenko <koevtushenko@yandex.com>
Signed-off-by: Sergey Bashirov <sergeybashirov@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20250630183537.196479-5-sergeybashirov@gmail.com
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

Author: sbashiro

fs/nfs/pnfs.c

@@ -3332,6 +3332,7 @@ pnfs_layoutcommit_inode(struct inode *inode, bool sync)
 	struct nfs_inode *nfsi = NFS_I(inode);
 	loff_t end_pos;
 	int status;
+	bool mark_as_dirty = false;
 
 	if (!pnfs_layoutcommit_outstanding(inode))
 		return 0;
@@ -3383,19 +3384,23 @@ pnfs_layoutcommit_inode(struct inode *inode, bool sync)
 	if (ld->prepare_layoutcommit) {
 		status = ld->prepare_layoutcommit(&data->args);
 		if (status) {
-			put_cred(data->cred);
+			if (status != -ENOSPC)
+				put_cred(data->cred);
 			spin_lock(&inode->i_lock);
 			set_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags);
 			if (end_pos > nfsi->layout->plh_lwb)
 				nfsi->layout->plh_lwb = end_pos;
-			goto out_unlock;
+			if (status != -ENOSPC)
+				goto out_unlock;
+			spin_unlock(&inode->i_lock);
+			mark_as_dirty = true;
 		}
 	}
 
 
 	status = nfs4_proc_layoutcommit(data, sync);
 out:
-	if (status)
+	if (status || mark_as_dirty)
 		mark_inode_dirty_sync(inode);
 	dprintk("<-- %s status %d\n", __func__, status);
 	return status;