libmultipath: hp_sw checker: leave unsupported paths alone
authorMartin Wilck <mwilck@suse.com>
Fri, 2 Nov 2018 12:21:18 +0000 (13:21 +0100)
committerChristophe Varoqui <christophe.varoqui@opensvc.com>
Wed, 14 Nov 2018 07:21:36 +0000 (08:21 +0100)
A checker shouldn't set the path state to PATH_DOWN if it fails
to obtain information about the path in the first place. Add logic
to the checker to distinguish a failed path from an unsupported path.

Reviewed-by: Benjamin Marzinski <bmarzins@redhat.com>
Signed-off-by: Martin Wilck <mwilck@suse.com>
libmultipath/checkers/hp_sw.c

index d7f1018..1a82022 100644 (file)
@@ -24,6 +24,7 @@
 #define SCSI_COMMAND_TERMINATED        0x22
 #define SG_ERR_DRIVER_SENSE    0x08
 #define RECOVERED_ERROR                0x01
+#define ILLEGAL_REQUEST                0x05
 #define MX_ALLOC_LEN           255
 #define HEAVY_CHECK_COUNT       10
 
@@ -68,14 +69,19 @@ do_inq(int sg_fd, int cmddt, int evpd, unsigned int pg_op,
        io_hdr.sbp = sense_b;
        io_hdr.timeout = timeout * 1000;
 
-       if (ioctl(sg_fd, SG_IO, &io_hdr) < 0)
-               return 1;
+       if (ioctl(sg_fd, SG_IO, &io_hdr) < 0) {
+               if (errno == ENOTTY)
+                       return PATH_WILD;
+               else
+                       return PATH_DOWN;
+       }
 
        /* treat SG_ERR here to get rid of sg_err.[ch] */
        io_hdr.status &= 0x7e;
        if ((0 == io_hdr.status) && (0 == io_hdr.host_status) &&
            (0 == io_hdr.driver_status))
-               return 0;
+               return PATH_UP;
+
        if ((SCSI_CHECK_CONDITION == io_hdr.status) ||
            (SCSI_COMMAND_TERMINATED == io_hdr.status) ||
            (SG_ERR_DRIVER_SENSE == (0xf & io_hdr.driver_status))) {
@@ -86,11 +92,13 @@ do_inq(int sg_fd, int cmddt, int evpd, unsigned int pg_op,
                                sense_key = sense_buffer[1] & 0xf;
                        else
                                sense_key = sense_buffer[2] & 0xf;
-                       if(RECOVERED_ERROR == sense_key)
-                               return 0;
+                       if (RECOVERED_ERROR == sense_key)
+                               return PATH_UP;
+                       else if (ILLEGAL_REQUEST == sense_key)
+                               return PATH_WILD;
                }
        }
-       return 1;
+       return PATH_DOWN;
 }
 
 static int
@@ -122,10 +130,15 @@ do_tur (int fd, unsigned int timeout)
 int libcheck_check(struct checker * c)
 {
        char buff[MX_ALLOC_LEN];
+       int ret = do_inq(c->fd, 0, 1, 0x80, buff, MX_ALLOC_LEN, 0, c->timeout);
 
-       if (0 != do_inq(c->fd, 0, 1, 0x80, buff, MX_ALLOC_LEN, 0, c->timeout)) {
+       if (ret == PATH_WILD) {
+               c->msgid = CHECKER_MSGID_UNSUPPORTED;
+               return ret;
+       }
+       if (ret != PATH_UP) {
                c->msgid = CHECKER_MSGID_DOWN;
-               return PATH_DOWN;
+               return ret;
        };
 
        if (do_tur(c->fd, c->timeout)) {