multipath: better check for daemon mode.

Switching to conf->daemon to check if we are in daemon mode.

Signed-off-by Benjamin Marzinski <[email protected]>

---
 libmultipath/dmparser.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

Index: multipath-tools-110713/libmultipath/dmparser.c
===================================================================

libmultipath/dmparser.c +2 -2

@@ -13,6 +13,7 @@
 #include "structs.h"
 #include "util.h"
 #include "debug.h"
+#include "config.h"
 
 #define WORD_SIZE 64
 

@@ -330,7 +331,7 @@ disassemble_map (vector pathvec, char * 
 				strncpy(pp->dev_t, word, BLK_DEV_SIZE);
 
 				/* Only call this in multipath client mode */
-				if (!mpp->waiter && store_path(pathvec, pp))
+				if (!conf->daemon && store_path(pathvec, pp))
 					goto out1;
 			}
 			FREE(word);
 
--

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Christophe, would it be possible to get this merged?

Thanks,
-Ben

Quoted 30 lines · Benjamin Marzinski

Switching to conf->daemon to check if we are in daemon mode.

Signed-off-by Benjamin Marzinski <[email protected]>

---
 libmultipath/dmparser.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

Index: multipath-tools-110713/libmultipath/dmparser.c
===================================================================

libmultipath/dmparser.c +2 -2

@@ -13,6 +13,7 @@
 #include "structs.h"
 #include "util.h"
 #include "debug.h"
+#include "config.h"
 
 #define WORD_SIZE 64
 

@@ -330,7 +331,7 @@ disassemble_map (vector pathvec, char * 
 				strncpy(pp->dev_t, word, BLK_DEV_SIZE);
 
 				/* Only call this in multipath client mode */
-				if (!mpp->waiter && store_path(pathvec, pp))
+				if (!conf->daemon && store_path(pathvec, pp))
 					goto out1;
 			}
 			FREE(word);
 
--

Quoted 3 lines

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Quoted 1 line · Benjamin Marzinski

Christophe, would it be possible to get this merged?

Is there some objection to merging this? It's not just a cosmetic change. For multipath devices added via ev_add_map(), disassemble_map() will be called before the waiter thread is started, and this check will allow any unknown paths in the device to be stored. However, paths added this way never get properly setup like they do when they are added via ev_add_path(), or at configuration time.

So say you had a multipath device, "mpatha", which should include the path "sda", except that the path was mistakenly blacklisted. If you unblacklist the path and then run multipath, without first reconfiguring multipathd, it will segfault, since it adds sda, but never initializes all the necessary information.

We could solve this problem by making sure that paths added through disassemble_map() go through the same initialization code that paths added through ev_add_path(), but I don't see the necessity. If multipathd isn't monitoring a path, it's either because that path was blacklisted, or because that path was manually removed. While it's possible to create a multipath device using blacklisted paths via dmsetup, multipathd still shouldn't be monitoring those paths. The same goes with paths that were manually removed via the multipathd command line interface.

And if, for some reason, multipathd wasn't monitoring a path it should be, the best thing to do is to reconfigure multipathd. Code that watched multipath.conf and automatically reconfigured multipathd when it changed would be a nice addition though.

Thanks,
-Ben

Quoted 42 lines

Thanks,
-Ben

Quoted 30 lines · Benjamin Marzinski

Switching to conf->daemon to check if we are in daemon mode.

Signed-off-by Benjamin Marzinski <[email protected]>

---
 libmultipath/dmparser.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

Index: multipath-tools-110713/libmultipath/dmparser.c
===================================================================

libmultipath/dmparser.c +2 -2

@@ -13,6 +13,7 @@
 #include "structs.h"
 #include "util.h"
 #include "debug.h"
+#include "config.h"
 
 #define WORD_SIZE 64
 

@@ -330,7 +331,7 @@ disassemble_map (vector pathvec, char * 
 				strncpy(pp->dev_t, word, BLK_DEV_SIZE);
 
 				/* Only call this in multipath client mode */
-				if (!mpp->waiter && store_path(pathvec, pp))
+				if (!conf->daemon && store_path(pathvec, pp))
 					goto out1;
 			}
 			FREE(word);
 
--

Quoted 3 lines

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Quoted 26 lines · Benjamin Marzinski

Quoted 1 line · Benjamin Marzinski

Christophe, would it be possible to get this merged?

Is there some objection to merging this? It's not just a cosmetic change. For multipath devices added via ev_add_map(), disassemble_map() will be called before the waiter thread is started, and this check will allow any unknown paths in the device to be stored. However, paths added this way never get properly setup like they do when they are added via ev_add_path(), or at configuration time.

So say you had a multipath device, "mpatha", which should include the path "sda", except that the path was mistakenly blacklisted. If you unblacklist the path and then run multipath, without first reconfiguring multipathd, it will segfault, since it adds sda, but never initializes all the necessary information.

We could solve this problem by making sure that paths added through disassemble_map() go through the same initialization code that paths added through ev_add_path(), but I don't see the necessity. If multipathd isn't monitoring a path, it's either because that path was blacklisted, or because that path was manually removed. While it's possible to create a multipath device using blacklisted paths via dmsetup, multipathd still shouldn't be monitoring those paths. The same goes with paths that were manually removed via the multipathd command line interface.

Quoted 5 lines

And if, for some reason, multipathd wasn't monitoring a path it should be, the best thing to do is to reconfigure multipathd. Code that watched multipath.conf and automatically reconfigured multipathd when it changed would be a nice addition though.

The multipath daemon should not segfault for sure. I agree the blacklisted paths can be left unmonitored even if they are part of configured multipath.

But I wouldn't do the multipath.conf changes auto loading. Admins tend to consider for granted daemons configuration files can be changed without impact on the running daemon.

Regards,
cvaroqui

Quoted 45 lines

Thanks,
-Ben

Quoted 42 lines

Thanks,
-Ben

Quoted 30 lines · Benjamin Marzinski

Switching to conf->daemon to check if we are in daemon mode.

Signed-off-by Benjamin Marzinski <[email protected]>

---
 libmultipath/dmparser.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

Index: multipath-tools-110713/libmultipath/dmparser.c
===================================================================

libmultipath/dmparser.c +2 -2

@@ -13,6 +13,7 @@
 #include "structs.h"
 #include "util.h"
 #include "debug.h"
+#include "config.h"
 
 #define WORD_SIZE 64
 

@@ -330,7 +331,7 @@ disassemble_map (vector pathvec, char * 
 				strncpy(pp->dev_t, word, BLK_DEV_SIZE);
 
 				/* Only call this in multipath client mode */
-				if (!mpp->waiter && store_path(pathvec, pp))
+				if (!conf->daemon && store_path(pathvec, pp))
 					goto out1;
 			}
 			FREE(word);
 
--

Quoted 3 lines

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