> -----Original Message----- > From: NeilBrown [mailto:neilb@xxxxxxx] > Sent: Thursday, February 09, 2012 02:36 > To: Kwolek, Adam > Cc: linux-raid@xxxxxxxxxxxxxxx; Ciechanowski, Ed; Labun, Marcin; Williams, Dan > J; Dorau, Lukasz > Subject: Re: [PATCH 08/12] FIX: use md position to reshape restart > > On Tue, 07 Feb 2012 15:03:59 +0100 Adam Kwolek <adam.kwolek@xxxxxxxxx> > wrote: > > > 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) { > ^^^ > > This test is '<=' however ... > > > > - 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) { > ^^ > > this one is just '<'. However it looks like it should be the same. > > Was there a reason for the change, or was it an oversight? > > Thanks, > NeilBrown > > > > > > ret_val = 1; > > goto Grow_continue_command_exit; > > } Removed code is put in to function verify_reshape_position() for use in current location and reshape_array(), as calculated new position in Grow_continue_command() cannot be passed to reshape_array(), it has to be calculated again. This is what you are mention above? BR Adam -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
