[libmultipath] Add new priority checker mpath_hp_sw

All paths from a controller with HP Active/Standby firmware
should really be grouped according to their status; otherwise
the path switching will not work properly or you can use only
one path to that array.
This patch adds a new priority checker 'mpath_hp_sw' which
will allow these paths to be grouped accordingly.

Signed-off-by: Hannes Reinecke <hare@suse.de>

diff --git a/path_priority/pp_hp_sw/Makefile b/path_priority/pp_hp_sw/Makefile
new file mode 100644 (file)
index 0000000..e7debf5
--- /dev/null
+++ b/path_priority/pp_hp_sw/Makefile
@@ -0,0 +1,25 @@
+EXEC           = mpath_prio_hp_sw
+BUILD          = glibc
+OBJS           = pp_hp_sw.o
+
+TOPDIR         = ../..
+include $(TOPDIR)/Makefile.inc
+
+all: $(BUILD)
+
+glibc: $(OBJS)
+       $(CC) -o $(EXEC) $(OBJS) $(LDFLAGS)
+
+klibc: $(OBJS)
+       $(CC) -static -o $(EXEC) $(OBJS)
+
+install: $(EXEC)
+       install -m 755 $(EXEC) $(DESTDIR)$(bindir)/$(EXEC)
+
+uninstall:
+       rm $(DESTDIR)$(bindir)/$(EXEC)
+clean: 
+       rm -f *.o $(EXEC)
+
+%.o:   %.c
+       $(CC) $(CFLAGS) -c -o $@ $<

diff --git a/path_priority/pp_hp_sw/pp_hp_sw.c b/path_priority/pp_hp_sw/pp_hp_sw.c
new file mode 100644 (file)
index 0000000..e4a18b1
--- /dev/null
+++ b/path_priority/pp_hp_sw/pp_hp_sw.c
@@ -0,0 +1,119 @@
+/*
+ * Path priority checker for HP active/standby controller
+ *
+ * Check the path state and sort them into groups.
+ * There is actually a preferred path in the controller;
+ * we should ask HP on how to retrieve that information.
+ */
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/ioctl.h>
+#include <errno.h>
+
+#define TUR_CMD_LEN            6
+#define SCSI_CHECK_CONDITION   0x2
+#define SCSI_COMMAND_TERMINATED        0x22
+#define SG_ERR_DRIVER_SENSE    0x08
+#define RECOVERED_ERROR                0x01
+#define NOT_READY              0x02
+#define UNIT_ATTENTION         0x06
+
+#define HP_PATH_ACTIVE         0x04
+#define HP_PATH_STANDBY                0x02
+#define HP_PATH_FAILED         0x00
+
+#include "../../libmultipath/sg_include.h"
+
+int hp_sw_prio(const char *dev)
+{
+        unsigned char turCmdBlk[TUR_CMD_LEN] = { 0x00, 0, 0, 0, 0, 0 };
+       unsigned char sb[128];
+       struct sg_io_hdr io_hdr;
+       int ret = HP_PATH_FAILED;
+       int fd;
+
+       fd = open(dev, O_RDWR|O_NONBLOCK);
+
+       if (fd <= 0) {
+               fprintf(stderr, "Opening the device failed.\n");
+               goto out;
+       }
+
+       memset(&io_hdr, 0, sizeof (struct sg_io_hdr));
+       io_hdr.interface_id = 'S';
+       io_hdr.cmd_len = sizeof (turCmdBlk);
+       io_hdr.mx_sb_len = sizeof (sb);
+       io_hdr.dxfer_direction = SG_DXFER_NONE;
+       io_hdr.cmdp = turCmdBlk;
+       io_hdr.sbp = sb;
+       io_hdr.timeout = 60000;
+       io_hdr.pack_id = 0;
+ retry:
+       if (ioctl(fd, SG_IO, &io_hdr) < 0) {
+               fprintf(stderr, "sending tur command failed\n");
+               goto out;
+       }
+        io_hdr.status &= 0x7e;
+        if ((0 == io_hdr.status) && (0 == io_hdr.host_status) &&
+            (0 == io_hdr.driver_status)) {
+               /* Command completed normally, path is active */
+                ret = HP_PATH_ACTIVE;
+       }
+
+        if ((SCSI_CHECK_CONDITION == io_hdr.status) ||
+            (SCSI_COMMAND_TERMINATED == io_hdr.status) ||
+            (SG_ERR_DRIVER_SENSE == (0xf & io_hdr.driver_status))) {
+                if (io_hdr.sbp && (io_hdr.sb_len_wr > 2)) {
+                        int sense_key, asc, asq;
+                        unsigned char * sense_buffer = io_hdr.sbp;
+                        if (sense_buffer[0] & 0x2) {
+                                sense_key = sense_buffer[1] & 0xf;
+                               asc = sense_buffer[2];
+                               asq = sense_buffer[3];
+                       } else {
+                                sense_key = sense_buffer[2] & 0xf;
+                               asc = sense_buffer[12];
+                               asq = sense_buffer[13];
+                       }
+                        if(RECOVERED_ERROR == sense_key)
+                                ret = HP_PATH_ACTIVE;
+                       if(NOT_READY == sense_key) {
+                               if (asc == 0x04 && asq == 0x02) {
+                                       /* This is a standby path */
+                                       ret = HP_PATH_STANDBY;
+                               }
+                       }
+                       if(UNIT_ATTENTION == sense_key) {
+                               if (asc == 0x29) {
+                                       /* Retry for device reset */
+                                       goto retry;
+                               }
+                       }
+                }
+        }
+
+       close(fd);
+
+out:
+       return(ret);
+}
+
+int
+main (int argc, char **argv)
+{
+       int prio;
+       if (argc != 2) {
+               fprintf(stderr, "Arguments wrong!\n");
+               prio = 0;
+       } else
+               prio = hp_sw_prio(argv[1]);
+
+       printf("%d\n", prio);
+       exit(0);
+}
+