Make sure child_monitor reliably reports whether reshape completed or aborted.

Signed-off-by: NeilBrown <neilb@suse.de>

diff --git a/Grow.c b/Grow.c
index 24d1d0ad0c6dc554aefc721bdcc7fee79669861c..488e7cf345fa5e109bce108d3ad62c4356125581 100644 (file)
--- a/Grow.c
+++ b/Grow.c
@@ -2216,6 +2216,7 @@ int progress_reshape(struct mdinfo *info, struct reshape *reshape,
        unsigned long long array_size = (info->component_size
                                         * reshape->before.data_disks);
        int fd;
+       char buf[20];
 
        /* First, we unsuspend any region that is now known to be safe.
         * If suspend_point is on the 'wrong' side of reshape_progress, then
@@ -2366,11 +2367,11 @@ int progress_reshape(struct mdinfo *info, struct reshape *reshape,
         */
        fd = sysfs_get_fd(info, NULL, "sync_completed");
        if (fd < 0)
-               return -1;
+               goto check_progress;
 
        if (sysfs_fd_get_ll(fd, &completed) < 0) {
                close(fd);
-               return -1;
+               goto check_progress;
        }
        while (completed < max_progress && completed < wait_point) {
                /* Check that sync_action is still 'reshape' to avoid
@@ -2387,7 +2388,7 @@ int progress_reshape(struct mdinfo *info, struct reshape *reshape,
                select(fd+1, NULL, NULL, &rfds, NULL);
                if (sysfs_fd_get_ll(fd, &completed) < 0) {
                        close(fd);
-                       return -1;
+                       goto check_progress;
                }
        }
        /* some kernels can give an incorrectly high 'completed' number */
@@ -2409,6 +2410,18 @@ int progress_reshape(struct mdinfo *info, struct reshape *reshape,
        return advancing
                ? (need_backup > info->reshape_progress)
                : (need_backup < info->reshape_progress);
+
+check_progress:
+       /* if we couldn't read a number from sync_completed, then
+        * either the reshape did complete, or it aborted.
+        * We can tell which by checking for 'none' in reshape_position.
+        */
+       strcpy(buf, "hi");
+       if (sysfs_get_str(info, NULL, "reshape_position", buf, sizeof(buf)) < 0
+           || strncmp(buf, "none", 4) != 0)
+               return -2; /* abort */
+       else
+               return -1; /* complete */
 }
 
 
@@ -2785,7 +2798,8 @@ int child_monitor(int afd, struct mdinfo *sra, struct reshape *reshape,
                }
 
                if (rv < 0) {
-                       done = 1;
+                       if (rv == -1)
+                               done = 1;
                        break;
                }
 
@@ -2840,7 +2854,7 @@ int child_monitor(int afd, struct mdinfo *sra, struct reshape *reshape,
        if (reshape->before.data_disks == reshape->after.data_disks)
                sysfs_set_num(sra, NULL, "sync_speed_min", speed);
        free(buf);
-       return 1; /* FIXME what does this mean? */
+       return done;
 }
 
 /*