From 1073621a7a63ca4e9a00baedd8edc51e5381eb95 Mon Sep 17 00:00:00 2001

From: Mike Christie <mchristi@redhat.com>

Date: Tue, 9 Aug 2016 13:46:11 -0500

Subject: [PATCH 03/11] multipath-tools: add checker callout to repair path

For BZ 1348372 from upstream commit:

commit 015f87b16a7797a17afd514aec46e65c2a1a2f73

Author: Mike Christie <mchristi@redhat.com>

Date:   Mon Aug 8 07:01:48 2016 -0500

    multipath-tools: add checker callout to repair path

    This patch adds a callback which can be used to repair a path

    if check() has determined it is in the PATH_DOWN state.

    The next patch that adds rbd checker support which will use this to

    handle the case where a rbd device is blacklisted.

--------

Porting notes:

checkerloop difference due to different path tracking.

Signed-off-by: Mike Christie <mchristi@redhat.com>

---

 libmultipath/checkers.c              | 23 +++++++++++++++++++++++

 libmultipath/checkers.h              |  4 ++++

 libmultipath/checkers/cciss_tur.c    |  5 +++++

 libmultipath/checkers/directio.c     |  5 +++++

 libmultipath/checkers/emc_clariion.c |  5 +++++

 libmultipath/checkers/hp_sw.c        |  5 +++++

 libmultipath/checkers/rdac.c         |  5 +++++

 libmultipath/checkers/readsector0.c  |  5 +++++

 libmultipath/checkers/tur.c          |  5 +++++

 multipathd/main.c                    |  9 +++++++++

 10 files changed, 71 insertions(+)

diff --git a/libmultipath/checkers.c b/libmultipath/checkers.c

index 7f9db2d..fa7d8b7 100644

--- a/libmultipath/checkers.c

+++ b/libmultipath/checkers.c

@@ -137,6 +137,14 @@ struct checker * add_checker (char * name)

 	if (!c->free)

 		goto out;

+	c->repair = (void (*)(struct checker *)) dlsym(c->handle,

+						       "libcheck_repair");

+	errstr = dlerror();

+	if (errstr != NULL)

+		condlog(0, "A dynamic linking error occurred: (%s)", errstr);

+	if (!c->repair)

+		goto out;

+

 	c->fd = 0;

 	c->sync = 1;

 	list_add(&c->node, &checkers);

@@ -202,6 +210,20 @@ void checker_put (struct checker * dst)

 	free_checker(src);

 }

+void checker_repair (struct checker * c)

+{

+	if (!c)

+		return;

+

+	c->message[0] = '\0';

+	if (c->disable) {

+		MSG(c, "checker disabled");

+		return;

+	}

+

+	c->repair(c);

+}

+

 int checker_check (struct checker * c)

 {

 	int r;

@@ -266,6 +288,7 @@ void checker_get (struct checker * dst, char * name)

 	dst->sync = src->sync;

 	strncpy(dst->name, src->name, CHECKER_NAME_LEN);

 	strncpy(dst->message, src->message, CHECKER_MSG_LEN);

+	dst->repair = src->repair;

 	dst->check = src->check;

 	dst->init = src->init;

 	dst->free = src->free;

diff --git a/libmultipath/checkers.h b/libmultipath/checkers.h

index 735bb25..ad3b9e4 100644

--- a/libmultipath/checkers.h

+++ b/libmultipath/checkers.h

@@ -106,6 +106,9 @@ struct checker {

 						multipath-wide. Use MALLOC if

 						you want to stuff data in. */

 	int (*check)(struct checker *);

+	void (*repair)(struct checker *);     /* called if check returns

+					        PATH_DOWN to bring path into

+						usable state */

 	int (*init)(struct checker *);       /* to allocate the context */

 	void (*free)(struct checker *);      /* to free the context */

 };

@@ -125,6 +128,7 @@ void checker_set_async (struct checker *);

 void checker_set_fd (struct checker *, int);

 void checker_enable (struct checker *);

 void checker_disable (struct checker *);

+void checker_repair (struct checker *);

 int checker_check (struct checker *);

 int checker_selected (struct checker *);

 char * checker_name (struct checker *);

diff --git a/libmultipath/checkers/cciss_tur.c b/libmultipath/checkers/cciss_tur.c

index 4c26901..7e4eb81 100644

--- a/libmultipath/checkers/cciss_tur.c

+++ b/libmultipath/checkers/cciss_tur.c

@@ -63,6 +63,11 @@ void libcheck_free (struct checker * c)

 	return;

 }

+void libcheck_repair (struct checker * c)

+{

+	return;

+}

+

 extern int

 libcheck_check (struct checker * c)

 {

diff --git a/libmultipath/checkers/directio.c b/libmultipath/checkers/directio.c

index 46fe6a7..1a997ed 100644

--- a/libmultipath/checkers/directio.c

+++ b/libmultipath/checkers/directio.c

@@ -116,6 +116,11 @@ void libcheck_free (struct checker * c)

 	free(ct);

 }

+void libcheck_repair (struct checker * c)

+{

+	return;

+}

+

 static int

 check_state(int fd, struct directio_context *ct, int sync, int timeout_secs)

 {

diff --git a/libmultipath/checkers/emc_clariion.c b/libmultipath/checkers/emc_clariion.c

index b42d267..43b5025 100644

--- a/libmultipath/checkers/emc_clariion.c

+++ b/libmultipath/checkers/emc_clariion.c

@@ -90,6 +90,11 @@ void libcheck_free (struct checker * c)

 	free(c->context);

 }

+void libcheck_repair (struct checker * c)

+{

+	return;

+}

+

 int libcheck_check (struct checker * c)

 {

 	unsigned char sense_buffer[128] = { 0, };

diff --git a/libmultipath/checkers/hp_sw.c b/libmultipath/checkers/hp_sw.c

index b50ac0c..857ac5e 100644

--- a/libmultipath/checkers/hp_sw.c

+++ b/libmultipath/checkers/hp_sw.c

@@ -44,6 +44,11 @@ void libcheck_free (struct checker * c)

 	return;

 }

+void libcheck_repair (struct checker * c)

+{

+	return;

+}

+

 static int

 do_inq(int sg_fd, int cmddt, int evpd, unsigned int pg_op,

        void *resp, int mx_resp_len, int noisy, unsigned int timeout)

diff --git a/libmultipath/checkers/rdac.c b/libmultipath/checkers/rdac.c

index f0e0af3..5469e61 100644

--- a/libmultipath/checkers/rdac.c

+++ b/libmultipath/checkers/rdac.c

@@ -139,6 +139,11 @@ void libcheck_free (struct checker * c)

 	return;

 }

+void libcheck_repair (struct checker * c)

+{

+	return;

+}

+

 static int

 do_inq(int sg_fd, unsigned int pg_op, void *resp, int mx_resp_len,

        unsigned int timeout)

diff --git a/libmultipath/checkers/readsector0.c b/libmultipath/checkers/readsector0.c

index 0550fb6..b3ed1f3 100644

--- a/libmultipath/checkers/readsector0.c

+++ b/libmultipath/checkers/readsector0.c

@@ -23,6 +23,11 @@ void libcheck_free (struct checker * c)

 	return;

 }

+void libcheck_repair (struct checker * c)

+{

+	return;

+}

+

 int libcheck_check (struct checker * c)

 {

 	unsigned char buf[4096];

diff --git a/libmultipath/checkers/tur.c b/libmultipath/checkers/tur.c

index 1e5b039..91f1458 100644

--- a/libmultipath/checkers/tur.c

+++ b/libmultipath/checkers/tur.c

@@ -187,6 +187,11 @@ void libcheck_free (struct checker * c)

 	return;

 }

+void libcheck_repair (struct checker * c)

+{

+	return;

+}

+

 #define TUR_MSG(msg, fmt, args...) snprintf(msg, CHECKER_MSG_LEN, fmt, ##args);

 int

diff --git a/multipathd/main.c b/multipathd/main.c

index 8808c88..d26fd22 100644

--- a/multipathd/main.c

+++ b/multipathd/main.c

@@ -1455,6 +1455,14 @@ check_path (struct vectors * vecs, struct path * pp)

 	}

 }

+void repair_path(struct vectors * vecs, struct path * pp)

+{

+	if (pp->state != PATH_DOWN)

+		return;

+

+	checker_repair(&pp->checker);

+}

+

 static void *

 checkerloop (void *ap)

 {

@@ -1483,6 +1491,7 @@ checkerloop (void *ap)

 		if (vecs->pathvec) {

 			vector_foreach_slot (vecs->pathvec, pp, i) {

 				check_path(vecs, pp);

+				repair_path(vecs, pp);

 			}

 		}

 		if (vecs->mpvec) {

-- 

1.8.3.1