From 276d77db1fd65eba4ef183635305e9ff297a6ce5 Mon Sep 17 00:00:00 2001 From: Adam Kwolek Date: Wed, 8 Jun 2011 17:11:23 +1000 Subject: [PATCH] imsm: Implement recover_backup_imsm() for imsm metadata Add ability to restore data backed up in General Migration Copy Area in case of unexpected reshape interruption. Function restores data during an array assembly and then reshape is continues from next checkpoint. Signed-off-by: Krzysztof Wojcik Signed-off-by: NeilBrown --- super-intel.c | 128 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 128 insertions(+) diff --git a/super-intel.c b/super-intel.c index d5bab17..2d79fd8 100644 --- a/super-intel.c +++ b/super-intel.c @@ -5293,6 +5293,7 @@ static void update_recovery_start(struct intel_super *super, rebuild->recovery_start = units * blocks_per_migr_unit(super, dev); } +static int recover_backup_imsm(struct supertype *st, struct mdinfo *info); static struct mdinfo *container_content_imsm(struct supertype *st, char *subarray) { @@ -5456,6 +5457,11 @@ static struct mdinfo *container_content_imsm(struct supertype *st, char *subarra /* now that the disk list is up-to-date fixup recovery_start */ update_recovery_start(super, dev, this); this->array.spare_disks += spare_disks; + + /* check for reshape */ + if (this->reshape_active == 1) + recover_backup_imsm(st, this); + rest = this; } @@ -7678,6 +7684,126 @@ int save_checkpoint_imsm(struct supertype *st, struct mdinfo *info, int state) return 0; } +static __u64 blocks_per_migr_unit(struct intel_super *super, + struct imsm_dev *dev); + +/******************************************************************************* + * Function: recover_backup_imsm + * Description: Function recovers critical data from the Migration Copy Area + * while assembling an array. + * Parameters: + * super : imsm internal array info + * info : general array info + * Returns: + * 0 : success (or there is no data to recover) + * 1 : fail + ******************************************************************************/ +int recover_backup_imsm(struct supertype *st, struct mdinfo *info) +{ + struct intel_super *super = st->sb; + struct migr_record *migr_rec = super->migr_rec; + struct imsm_map *map_dest = NULL; + struct intel_dev *id = NULL; + unsigned long long read_offset; + unsigned long long write_offset; + unsigned unit_len; + int *targets = NULL; + int new_disks, i, err; + char *buf = NULL; + int retval = 1; + unsigned long curr_migr_unit = __le32_to_cpu(migr_rec->curr_migr_unit); + unsigned long num_migr_units = __le32_to_cpu(migr_rec->num_migr_units); + int ascending = __le32_to_cpu(migr_rec->ascending_migr); + char buffer[20]; + + err = sysfs_get_str(info, NULL, "array_state", (char *)buffer, 20); + if (err < 1) + return 1; + + /* recover data only during assemblation */ + if (strncmp(buffer, "inactive", 8) != 0) + return 0; + /* no data to recover */ + if (__le32_to_cpu(migr_rec->rec_status) == UNIT_SRC_NORMAL) + return 0; + if (curr_migr_unit >= num_migr_units) + return 1; + + /* find device during reshape */ + for (id = super->devlist; id; id = id->next) + if (is_gen_migration(id->dev)) + break; + if (id == NULL) + return 1; + + map_dest = get_imsm_map(id->dev, 0); + new_disks = map_dest->num_members; + + read_offset = (unsigned long long) + __le32_to_cpu(migr_rec->ckpt_area_pba) * 512; + + write_offset = ((unsigned long long) + __le32_to_cpu(migr_rec->dest_1st_member_lba) + + info->data_offset) * 512; + + unit_len = __le32_to_cpu(migr_rec->dest_depth_per_unit) * 512; + if (posix_memalign((void **)&buf, 512, unit_len) != 0) + goto abort; + targets = malloc(new_disks * sizeof(int)); + if (!targets) + goto abort; + + open_backup_targets(info, new_disks, targets); + + for (i = 0; i < new_disks; i++) { + if (lseek64(targets[i], read_offset, SEEK_SET) < 0) { + fprintf(stderr, + Name ": Cannot seek to block: %s\n", + strerror(errno)); + goto abort; + } + if (read(targets[i], buf, unit_len) != unit_len) { + fprintf(stderr, + Name ": Cannot read copy area block: %s\n", + strerror(errno)); + goto abort; + } + if (lseek64(targets[i], write_offset, SEEK_SET) < 0) { + fprintf(stderr, + Name ": Cannot seek to block: %s\n", + strerror(errno)); + goto abort; + } + if (write(targets[i], buf, unit_len) != unit_len) { + fprintf(stderr, + Name ": Cannot restore block: %s\n", + strerror(errno)); + goto abort; + } + } + + if (ascending && curr_migr_unit < (num_migr_units-1)) + curr_migr_unit++; + + migr_rec->curr_migr_unit = __le32_to_cpu(curr_migr_unit); + super->migr_rec->rec_status = __cpu_to_le32(UNIT_SRC_NORMAL); + if (write_imsm_migr_rec(st) == 0) { + __u64 blocks_per_unit = blocks_per_migr_unit(super, id->dev); + info->reshape_progress = curr_migr_unit * blocks_per_unit; + retval = 0; + } + +abort: + if (targets) { + for (i = 0; i < new_disks; i++) + if (targets[i]) + close(targets[i]); + free(targets); + } + free(buf); + return retval; +} + static char disk_by_path[] = "/dev/disk/by-path/"; static const char *imsm_get_disk_controller_domain(const char *path) @@ -8695,6 +8821,8 @@ struct superswitch super_imsm = { .match_metadata_desc = match_metadata_desc_imsm, .container_content = container_content_imsm, + .recover_backup = recover_backup_imsm, + .external = 1, .name = "imsm",