From 73c0f228250ff7fc1d662b64123f2aea9d04ca7e Mon Sep 17 00:00:00 2001 From: Liu Bo Date: Tue, 14 Mar 2017 13:33:58 -0700 Subject: [PATCH] Btrfs: handle operations for device replace separately Since this part is mostly independent, this moves it to a separate function. Reviewed-by: Qu Wenruo Signed-off-by: Liu Bo Signed-off-by: David Sterba --- fs/btrfs/volumes.c | 179 +++++++++++++++++++++++++-------------------- 1 file changed, 98 insertions(+), 81 deletions(-) diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index 8865e440736a..f27f9cebce24 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -5532,6 +5532,100 @@ static int get_extra_mirror_from_replace(struct btrfs_fs_info *fs_info, return ret; } +static void handle_ops_on_dev_replace(enum btrfs_map_op op, + struct btrfs_bio **bbio_ret, + struct btrfs_dev_replace *dev_replace, + int *num_stripes_ret, int *max_errors_ret) +{ + struct btrfs_bio *bbio = *bbio_ret; + u64 srcdev_devid = dev_replace->srcdev->devid; + int tgtdev_indexes = 0; + int num_stripes = *num_stripes_ret; + int max_errors = *max_errors_ret; + int i; + + if (op == BTRFS_MAP_WRITE) { + int index_where_to_add; + + /* + * duplicate the write operations while the dev replace + * procedure is running. Since the copying of the old disk to + * the new disk takes place at run time while the filesystem is + * mounted writable, the regular write operations to the old + * disk have to be duplicated to go to the new disk as well. + * + * Note that device->missing is handled by the caller, and that + * the write to the old disk is already set up in the stripes + * array. + */ + index_where_to_add = num_stripes; + for (i = 0; i < num_stripes; i++) { + if (bbio->stripes[i].dev->devid == srcdev_devid) { + /* write to new disk, too */ + struct btrfs_bio_stripe *new = + bbio->stripes + index_where_to_add; + struct btrfs_bio_stripe *old = + bbio->stripes + i; + + new->physical = old->physical; + new->length = old->length; + new->dev = dev_replace->tgtdev; + bbio->tgtdev_map[i] = index_where_to_add; + index_where_to_add++; + max_errors++; + tgtdev_indexes++; + } + } + num_stripes = index_where_to_add; + } else if (op == BTRFS_MAP_GET_READ_MIRRORS) { + int index_srcdev = 0; + int found = 0; + u64 physical_of_found = 0; + + /* + * During the dev-replace procedure, the target drive can also + * be used to read data in case it is needed to repair a corrupt + * block elsewhere. This is possible if the requested area is + * left of the left cursor. In this area, the target drive is a + * full copy of the source drive. + */ + for (i = 0; i < num_stripes; i++) { + if (bbio->stripes[i].dev->devid == srcdev_devid) { + /* + * 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; + } + } + if (found) { + struct btrfs_bio_stripe *tgtdev_stripe = + bbio->stripes + num_stripes; + + tgtdev_stripe->physical = physical_of_found; + tgtdev_stripe->length = + bbio->stripes[index_srcdev].length; + tgtdev_stripe->dev = dev_replace->tgtdev; + bbio->tgtdev_map[index_srcdev] = num_stripes; + + tgtdev_indexes++; + num_stripes++; + } + } + + *num_stripes_ret = num_stripes; + *max_errors_ret = max_errors; + bbio->num_tgtdevs = tgtdev_indexes; + *bbio_ret = bbio; +} + static int __btrfs_map_block(struct btrfs_fs_info *fs_info, enum btrfs_map_op op, u64 logical, u64 *length, @@ -5812,86 +5906,10 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info, if (bbio->raid_map) sort_parity_stripes(bbio, num_stripes); - tgtdev_indexes = 0; - if (dev_replace_is_ongoing && op == BTRFS_MAP_WRITE && - dev_replace->tgtdev != NULL) { - int index_where_to_add; - u64 srcdev_devid = dev_replace->srcdev->devid; - - /* - * duplicate the write operations while the dev replace - * procedure is running. Since the copying of the old disk - * to the new disk takes place at run time while the - * filesystem is mounted writable, the regular write - * operations to the old disk have to be duplicated to go - * to the new disk as well. - * Note that device->missing is handled by the caller, and - * that the write to the old disk is already set up in the - * stripes array. - */ - index_where_to_add = num_stripes; - for (i = 0; i < num_stripes; i++) { - if (bbio->stripes[i].dev->devid == srcdev_devid) { - /* write to new disk, too */ - struct btrfs_bio_stripe *new = - bbio->stripes + index_where_to_add; - struct btrfs_bio_stripe *old = - bbio->stripes + i; - - new->physical = old->physical; - new->length = old->length; - new->dev = dev_replace->tgtdev; - bbio->tgtdev_map[i] = index_where_to_add; - index_where_to_add++; - max_errors++; - tgtdev_indexes++; - } - } - num_stripes = index_where_to_add; - } else if (dev_replace_is_ongoing && - op == BTRFS_MAP_GET_READ_MIRRORS && - dev_replace->tgtdev != NULL) { - u64 srcdev_devid = dev_replace->srcdev->devid; - int index_srcdev = 0; - int found = 0; - u64 physical_of_found = 0; - - /* - * During the dev-replace procedure, the target drive can - * also be used to read data in case it is needed to repair - * a corrupt block elsewhere. This is possible if the - * requested area is left of the left cursor. In this area, - * the target drive is a full copy of the source drive. - */ - for (i = 0; i < num_stripes; i++) { - if (bbio->stripes[i].dev->devid == srcdev_devid) { - /* - * 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; - } - } - if (found) { - struct btrfs_bio_stripe *tgtdev_stripe = - bbio->stripes + num_stripes; - - tgtdev_stripe->physical = physical_of_found; - tgtdev_stripe->length = - bbio->stripes[index_srcdev].length; - tgtdev_stripe->dev = dev_replace->tgtdev; - bbio->tgtdev_map[index_srcdev] = num_stripes; - - tgtdev_indexes++; - num_stripes++; - } + if (dev_replace_is_ongoing && dev_replace->tgtdev != NULL && + (op == BTRFS_MAP_WRITE || op == BTRFS_MAP_GET_READ_MIRRORS)) { + handle_ops_on_dev_replace(op, &bbio, dev_replace, &num_stripes, + &max_errors); } *bbio_ret = bbio; @@ -5899,7 +5917,6 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info, bbio->num_stripes = num_stripes; bbio->max_errors = max_errors; bbio->mirror_num = mirror_num; - bbio->num_tgtdevs = tgtdev_indexes; /* * this is the case that REQ_READ && dev_replace_is_ongoing && -- 2.20.1