From 18069b2bc221820b552e108a95d91b396d07fb07 Mon Sep 17 00:00:00 2001
From: Sage Weil <sage@newdream.net>
Date: Fri, 22 Aug 2008 16:55:58 -0700
Subject: [PATCH] kclient: retry sync_write on EOLDSNAP

---
 src/include/ceph_fs.h   | 4 +++-
 src/kernel/file.c       | 9 +++++++++
 src/kernel/osd_client.c | 3 ++-
 3 files changed, 14 insertions(+), 2 deletions(-)

diff --git a/src/include/ceph_fs.h b/src/include/ceph_fs.h
index 28c59a4d466c9..1a19b79e68e81 100644
--- a/src/include/ceph_fs.h
+++ b/src/include/ceph_fs.h
@@ -1013,9 +1013,11 @@ enum {
 	CEPH_OSD_OP_INCLOCK_FAIL = 8, /* fail on inclock collision */
 	CEPH_OSD_OP_BALANCE_READS = 16,
 	CEPH_OSD_OP_ACKNVRAM = 32,    /* ACK when stable in NVRAM, not RAM */
-	CEPH_OSD_OP_ORDERSNAP = 64,   /* fail (EBADF) if snap ordering is incorrect */
+	CEPH_OSD_OP_ORDERSNAP = 64,   /* EOLDSNAP if snapc is out of order */
 };
 
+#define EOLDSNAPC 44 /* ORDERSNAP specified and writer has old snap context*/
+
 struct ceph_osd_peer_stat {
 	struct ceph_timespec stamp;
 	float oprate;
diff --git a/src/kernel/file.c b/src/kernel/file.c
index ef36e6d96b264..a993ff1e149d4 100644
--- a/src/kernel/file.c
+++ b/src/kernel/file.c
@@ -251,6 +251,7 @@ static ssize_t ceph_sync_write(struct file *file, const char __user *data,
 		if (pos > i_size_read(inode))
 			ceph_inode_set_size(inode, pos);
 	}
+
 	return ret;
 }
 
@@ -335,6 +336,7 @@ ssize_t ceph_aio_write(struct kiocb *iocb, const struct iovec *iov,
 	if (ceph_snap(inode) != CEPH_NOSNAP)
 		return -EROFS;
 
+retry_snap:
 	__ceph_do_pending_vmtruncate(inode);
 	check_max_size(inode, endoff);
 	dout(10, "aio_write %p %llu~%u getting caps. i_size %llu\n",
@@ -361,6 +363,13 @@ out:
 	dout(10, "aio_write %p %llu~%u  dropping cap refs on %d\n",
 	     inode, pos, (unsigned)iov->iov_len, got);
 	ceph_put_cap_refs(ci, got);
+
+	if (ret == -EOLDSNAPC) {
+		dout(10, "aio_write %p %llu~%u got EOLDSNAPC, retrying\n",
+		     inode, pos, (unsigned)iov->iov_len);
+		goto retry_snap;
+	}
+
 	return ret;
 }
 
diff --git a/src/kernel/osd_client.c b/src/kernel/osd_client.c
index 06a139c6e1fbe..355402f020434 100644
--- a/src/kernel/osd_client.c
+++ b/src/kernel/osd_client.c
@@ -798,7 +798,8 @@ int ceph_osdc_sync_write(struct ceph_osd_client *osdc, struct ceph_vino vino,
 	if (IS_ERR(reqm))
 		return PTR_ERR(reqm);
 	reqhead = reqm->front.iov_base;
-	reqhead->flags = CEPH_OSD_OP_ACK;  /* just ack.. FIXME */
+	reqhead->flags = CEPH_OSD_OP_ACK | /* just ack for now... FIXME */
+		CEPH_OSD_OP_ORDERSNAP;     /* get EOLDSNAPC if out of order */
 
 	/* how many pages? */
 	num_pages = calc_pages_for(off, len);
-- 
2.39.5