diff options
| -rw-r--r-- | fs/btrfs/volumes.c | 161 |
1 files changed, 89 insertions, 72 deletions
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index d777d626aa87..8865e440736a 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -139,6 +139,11 @@ static int btrfs_relocate_sys_chunks(struct btrfs_fs_info *fs_info); static void __btrfs_reset_dev_stats(struct btrfs_device *dev); static void btrfs_dev_stat_print_on_error(struct btrfs_device *dev); static void btrfs_dev_stat_print_on_load(struct btrfs_device *device); +static int __btrfs_map_block(struct btrfs_fs_info *fs_info, + enum btrfs_map_op op, + u64 logical, u64 *length, + struct btrfs_bio **bbio_ret, + int mirror_num, int need_raid_map); DEFINE_MUTEX(uuid_mutex); static LIST_HEAD(fs_uuids); @@ -5450,6 +5455,83 @@ out: return ret; } +/* + * In dev-replace case, for repair case (that's the only case where the mirror + * is selected explicitly when calling btrfs_map_block), blocks left of the + * left cursor can also be read from the target drive. + * + * For REQ_GET_READ_MIRRORS, the target drive is added as the last one to the + * array of stripes. + * For READ, it also needs to be supported using the same mirror number. + * + * If the requested block is not left of the left cursor, EIO is returned. This + * can happen because btrfs_num_copies() returns one more in the dev-replace + * case. + */ +static int get_extra_mirror_from_replace(struct btrfs_fs_info *fs_info, + u64 logical, u64 length, + u64 srcdev_devid, int *mirror_num, + u64 *physical) +{ + struct btrfs_bio *bbio = NULL; + int num_stripes; + int index_srcdev = 0; + int found = 0; + u64 physical_of_found = 0; + int i; + int ret = 0; + + ret = __btrfs_map_block(fs_info, BTRFS_MAP_GET_READ_MIRRORS, + logical, &length, &bbio, 0, 0); + if (ret) { + ASSERT(bbio == NULL); + return ret; + } + + num_stripes = bbio->num_stripes; + if (*mirror_num > num_stripes) { + /* + * BTRFS_MAP_GET_READ_MIRRORS does not contain this mirror, + * that means that the requested area is not left of the left + * cursor + */ + btrfs_put_bbio(bbio); + return -EIO; + } + + /* + * process the rest of the function using the mirror_num of the source + * drive. Therefore look it up first. At the end, patch the device + * pointer to the one of the target drive. + */ + for (i = 0; i < num_stripes; i++) { + if (bbio->stripes[i].dev->devid != srcdev_devid) + continue; + + /* + * In case of DUP, in order to keep it simple, only add the + * mirror with the lowest physical address + */ + if (found && + physical_of_found <= bbio->stripes[i].physical) + continue; + + index_srcdev = i; + found = 1; + physical_of_found = bbio->stripes[i].physical; + } + + btrfs_put_bbio(bbio); + + ASSERT(found); + if (!found) + return -EIO; + + *mirror_num = index_srcdev + 1; + *physical = physical_of_found; + return ret; +} + static int __btrfs_map_block(struct btrfs_fs_info *fs_info, enum btrfs_map_op op, u64 logical, u64 *length, @@ -5554,79 +5636,14 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info, if (dev_replace_is_ongoing && mirror_num == map->num_stripes + 1 && op != BTRFS_MAP_WRITE && op != BTRFS_MAP_GET_READ_MIRRORS && dev_replace->tgtdev != NULL) { - /* - * in dev-replace case, for repair case (that's the only - * case where the mirror is selected explicitly when - * calling btrfs_map_block), blocks left of the left cursor - * can also be read from the target drive. - * For REQ_GET_READ_MIRRORS, the target drive is added as - * the last one to the array of stripes. For READ, it also - * needs to be supported using the same mirror number. - * If the requested block is not left of the left cursor, - * EIO is returned. This can happen because btrfs_num_copies() - * returns one more in the dev-replace case. - */ - u64 tmp_length = *length; - struct btrfs_bio *tmp_bbio = NULL; - int tmp_num_stripes; - u64 srcdev_devid = dev_replace->srcdev->devid; - int index_srcdev = 0; - int found = 0; - u64 physical_of_found = 0; - - ret = __btrfs_map_block(fs_info, BTRFS_MAP_GET_READ_MIRRORS, - logical, &tmp_length, &tmp_bbio, 0, 0); - if (ret) { - WARN_ON(tmp_bbio != NULL); - goto out; - } - - tmp_num_stripes = tmp_bbio->num_stripes; - if (mirror_num > tmp_num_stripes) { - /* - * BTRFS_MAP_GET_READ_MIRRORS does not contain this - * mirror, that means that the requested area - * is not left of the left cursor - */ - ret = -EIO; - btrfs_put_bbio(tmp_bbio); - goto out; - } - - /* - * process the rest of the function using the mirror_num - * of the source drive. Therefore look it up first. - * At the end, patch the device pointer to the one of the - * target drive. - */ - for (i = 0; i < tmp_num_stripes; i++) { - if (tmp_bbio->stripes[i].dev->devid != srcdev_devid) - continue; - - /* - * In case of DUP, in order to keep it simple, only add - * the mirror with the lowest physical address - */ - if (found && - physical_of_found <= tmp_bbio->stripes[i].physical) - continue; - - index_srcdev = i; - found = 1; - physical_of_found = tmp_bbio->stripes[i].physical; - } - - btrfs_put_bbio(tmp_bbio); - - if (!found) { - WARN_ON(1); - ret = -EIO; + ret = get_extra_mirror_from_replace(fs_info, logical, *length, + dev_replace->srcdev->devid, + &mirror_num, + &physical_to_patch_in_first_stripe); + if (ret) goto out; - } - - mirror_num = index_srcdev + 1; - patch_the_first_stripe_for_dev_replace = 1; - physical_to_patch_in_first_stripe = physical_of_found; + else + patch_the_first_stripe_for_dev_replace = 1; } else if (mirror_num > map->num_stripes) { mirror_num = 0; } |
