When reshape is broken, it can occur that metadata is not saved properly.
This can cause that reshape process is farther in md than metadata states.
On reshape restart use md position as start position, if it is farther than
position specified in metadata. Opposite situation treat as error.
Signed-off-by: Adam Kwolek <adam.kwolek@xxxxxxxxx>
---
Grow.c | 86 +++++++++++++++++++++++++++++++++++++++++++++-------------------
1 files changed, 60 insertions(+), 26 deletions(-)
diff --git a/Grow.c b/Grow.c
index 70bdee1..0668a16 100644
--- a/Grow.c
+++ b/Grow.c
@@ -1862,6 +1862,55 @@ release:
return rv;
}
+/* verify_reshape_position()
+ * Function checks if reshape position in metadata is not farther
+ * than position in md.
+ * Return value:
+ * 0 : not valid sysfs entry
+ * it can be caused by not started reshape, it should be started
+ * by reshape array or raid0 array is before takeover
+ * -1 : error, reshape position is obviously wrong
+ * 1 : success, reshape progress correct or updated
+*/
+static int verify_reshape_position(struct mdinfo *info, int level)
+{
+ int ret_val = 0;
+ char buf[40];
+
+ /* read sync_max, failure can mean raid0 array */
+ if (sysfs_get_str(info, NULL, "sync_max", buf, 40) > 0) {
+ char *ep;
+ unsigned long long position = strtoull(buf, &ep, 0);
+
+ dprintf(Name": Read sync_max sysfs entry is: %s\n", buf);
+ if (!(ep == buf || (*ep != 0 && *ep != '\n' && *ep != ' '))) {
+ position *= get_data_disks(level,
+ info->new_layout,
+ info->array.raid_disks);
+ if (info->reshape_progress < position) {
+ dprintf("Corrected reshape progress (%llu) to "
+ "md position (%llu)\n",
+ info->reshape_progress, position);
+ info->reshape_progress = position;
+ ret_val = 1;
+ } else if (info->reshape_progress > position) {
+ fprintf(stderr, Name ": Fatal error: array "
+ "reshape was not properly frozen "
+ "(expected reshape position is %llu, "
+ "but reshape progress is %llu.\n",
+ position, info->reshape_progress);
+ ret_val = -1;
+ } else {
+ dprintf("Reshape position in md and metadata "
+ "are the same;");
+ ret_val = 1;
+ }
+ }
+ }
+
+ return ret_val;
+}
+
static int reshape_array(char *container, int fd, char *devname,
struct supertype *st, struct mdinfo *info,
int force, struct mddev_dev *devlist,
@@ -2251,9 +2300,16 @@ started:
sra->new_chunk = info->new_chunk;
- if (restart)
+ if (restart) {
+ /* for external metadata checkpoint saved by mdmon can be lost
+ * or missed /due to e.g. crash/. Check if md is not during
+ * restart farther than metadata points to.
+ * If so, this means metadata information is obsolete.
+ */
+ if (st->ss->external)
+ verify_reshape_position(info, reshape.level);
sra->reshape_progress = info->reshape_progress;
- else {
+ } else {
sra->reshape_progress = 0;
if (reshape.after.data_disks < reshape.before.data_disks)
/* start from the end of the new array */
@@ -3765,8 +3821,6 @@ int Grow_continue_command(char *devname, int fd,
char buf[40];
int cfd = -1;
int fd2 = -1;
- char *ep;
- unsigned long long position;
dprintf("Grow continue from command line called for %s\n",
devname);
@@ -3894,28 +3948,8 @@ int Grow_continue_command(char *devname, int fd,
/* verify that array under reshape is started from
* correct position
*/
- ret_val = sysfs_get_str(content, NULL, "sync_max", buf, 40);
- if (ret_val <= 0) {
- fprintf(stderr, Name
- ": cannot open verify reshape progress for %s (%i)\n",
- content->sys_name, ret_val);
- ret_val = 1;
- goto Grow_continue_command_exit;
- }
- dprintf(Name ": Read sync_max sysfs entry is: %s\n", buf);
- position = strtoull(buf, &ep, 0);
- if (ep == buf || (*ep != 0 && *ep != '\n' && *ep != ' ')) {
- fprintf(stderr, Name ": Fatal error: array reshape was"
- " not properly frozen\n");
- ret_val = 1;
- goto Grow_continue_command_exit;
- }
- position *= get_data_disks(map_name(pers, mdstat->level),
- content->new_layout,
- content->array.raid_disks);
- if (position != content->reshape_progress) {
- fprintf(stderr, Name ": Fatal error: array reshape was"
- " not properly frozen.\n");
+ if (verify_reshape_position(content,
+ map_name(pers, mdstat->level)) < 0) {
ret_val = 1;
goto Grow_continue_command_exit;
}
--
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