From a2b85d13e50327da721e32071aecad21b10ffb1a Mon Sep 17 00:00:00 2001
From: Pranith Kumar K <pkarampu@redhat.com>
Date: Thu, 15 Nov 2012 23:07:24 +0530
Subject: cluster/afr: Fail readv on data-split-brain

Problem:
Afr prevents opens on a file in split-brian but the
fd that is already open still has the capability to perform
both reads and writes to the file.

Fix:
Fail readvs on a file with EIO.

Change-Id: I8e07f24c36fab800499b36ab374f984b743332cd
BUG: 873962
Signed-off-by: Pranith Kumar K <pkarampu@redhat.com>
Reviewed-on: http://review.gluster.org/4199
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Jeff Darcy <jdarcy@redhat.com>
Reviewed-by: Anand Avati <avati@redhat.com>
---
 tests/bugs/bug-873962-spb.t              | 39 ++++++++++++++++++++++++++++++++
 xlators/cluster/afr/src/afr-common.c     | 15 ++++++++++++
 xlators/cluster/afr/src/afr-inode-read.c |  5 ++++
 xlators/cluster/afr/src/afr.h            |  3 +++
 4 files changed, 62 insertions(+)
 create mode 100644 tests/bugs/bug-873962-spb.t

diff --git a/tests/bugs/bug-873962-spb.t b/tests/bugs/bug-873962-spb.t
new file mode 100644
index 000000000..62a8318ed
--- /dev/null
+++ b/tests/bugs/bug-873962-spb.t
@@ -0,0 +1,39 @@
+#!/bin/bash
+
+. $(dirname $0)/../include.rc
+. $(dirname $0)/../volume.rc
+
+cleanup;
+TEST glusterd
+TEST pidof glusterd
+
+TEST $CLI volume create $V0 replica 2 $H0:$B0/${V0}{0,1}
+TEST $CLI volume set $V0 cluster.self-heal-daemon off
+TEST $CLI volume set $V0 performance.quick-read off
+TEST $CLI volume set $V0 performance.io-cache off
+TEST $CLI volume set $V0 performance.write-behind off
+TEST $CLI volume set $V0 performance.stat-prefetch off
+TEST $CLI volume set $V0 performance.read-ahead off
+TEST $CLI volume set $V0 cluster.background-self-heal-count 0
+TEST $CLI volume start $V0
+TEST glusterfs --entry-timeout=0 --attribute-timeout=0 -s $H0 --volfile-id=$V0 $M0 --direct-io-mode=enable
+touch $M0/a
+
+exec 5<$M0/a
+
+kill_brick $V0 $H0 $B0/${V0}0
+echo "hi" > $M0/a
+TEST $CLI volume start $V0 force
+EXPECT_WITHIN 20 "1" afr_child_up_status $V0 0
+
+kill_brick $V0 $H0 $B0/${V0}1
+echo "bye" > $M0/a
+TEST $CLI volume start $V0 force
+EXPECT_WITHIN 20 "1" afr_child_up_status $V0 1
+
+TEST ! cat $M0/a #To mark split-brain
+
+TEST ! read -u 5 line
+exec 5<&-
+
+cleanup;
diff --git a/xlators/cluster/afr/src/afr-common.c b/xlators/cluster/afr/src/afr-common.c
index 97303d106..dbd64cb24 100644
--- a/xlators/cluster/afr/src/afr-common.c
+++ b/xlators/cluster/afr/src/afr-common.c
@@ -324,6 +324,21 @@ out:
         return spb;
 }
 
+gf_boolean_t
+afr_is_data_split_brain (xlator_t *this, inode_t *inode)
+{
+        afr_inode_ctx_t *ctx = NULL;
+        gf_boolean_t    spb  = _gf_false;
+
+        ctx = afr_inode_ctx_get (inode, this);
+        if (!ctx)
+                goto out;
+        if (ctx->data_spb == SPB)
+                spb = _gf_true;
+out:
+        return spb;
+}
+
 gf_boolean_t
 afr_is_opendir_done (xlator_t *this, inode_t *inode)
 {
diff --git a/xlators/cluster/afr/src/afr-inode-read.c b/xlators/cluster/afr/src/afr-inode-read.c
index 1b3f74051..40d57b6f9 100644
--- a/xlators/cluster/afr/src/afr-inode-read.c
+++ b/xlators/cluster/afr/src/afr-inode-read.c
@@ -1813,6 +1813,11 @@ afr_readv (call_frame_t *frame, xlator_t *this,
         priv     = this->private;
         children = priv->children;
 
+        if (afr_is_data_split_brain (this, fd->inode)) {
+                op_errno = EIO;
+                goto out;
+        }
+
         AFR_LOCAL_ALLOC_OR_GOTO (frame->local, out);
         local = frame->local;
 
diff --git a/xlators/cluster/afr/src/afr.h b/xlators/cluster/afr/src/afr.h
index 85b4b6831..a9c063704 100644
--- a/xlators/cluster/afr/src/afr.h
+++ b/xlators/cluster/afr/src/afr.h
@@ -836,6 +836,9 @@ afr_frame_return (call_frame_t *frame);
 gf_boolean_t
 afr_is_split_brain (xlator_t *this, inode_t *inode);
 
+gf_boolean_t
+afr_is_data_split_brain (xlator_t *this, inode_t *inode);
+
 void
 afr_set_split_brain (xlator_t *this, inode_t *inode, afr_spb_state_t mdata_spb,
                      afr_spb_state_t data_spb);
-- 
cgit