On 07/08/2016 07:23 AM, Christoph Hellwig wrote: > So far we tried to rely on the SCSI 'all target ports' bit to register > all path, but for many setups this didn't work properly as the different > path aren seen as separate initiators to the target instead of multiple > ports of the same initiator. Because of that we'll stop setting the > 'all target ports' bit in SCSI, and let device mapper handle iterating > over the device for each path and register it manually. > > Signed-off-by: Christoph Hellwig <[email protected]> > --- > drivers/md/dm.c | 85 > +++++++++++++++++++++++++++++++++++++++++++++++---------- > 1 file changed, 70 insertions(+), 15 deletions(-) > > diff --git a/drivers/md/dm.c b/drivers/md/dm.c > index 1b2f962..e4e98b7 100644 > --- a/drivers/md/dm.c > +++ b/drivers/md/dm.c > @@ -3601,26 +3601,81 @@ void dm_free_md_mempools(struct dm_md_mempools *pools) > kfree(pools); > } > > -static int dm_pr_register(struct block_device *bdev, u64 old_key, u64 > new_key, > - u32 flags) > +struct dm_pr { > + u64 old_key; > + u64 new_key; > + u32 flags; > + bool fail_early; > +}; > + > +static int dm_call_pr(struct block_device *bdev, iterate_devices_callout_fn > fn, > + void *data) > { > struct mapped_device *md = bdev->bd_disk->private_data; > - const struct pr_ops *ops; > - fmode_t mode; > - int r; > + struct dm_table *table; > + struct dm_target *ti; > + int ret = 0, srcu_idx; > > - r = dm_grab_bdev_for_ioctl(md, &bdev, &mode); > - if (r < 0) > - return r; > + table = dm_get_live_table(md, &srcu_idx); > + if (!table || !dm_table_get_size(table)) > + return -ENOTTY; > > - ops = bdev->bd_disk->fops->pr_ops; > - if (ops && ops->pr_register) > - r = ops->pr_register(bdev, old_key, new_key, flags); > - else > - r = -EOPNOTSUPP; > + /* We only support devices that have a single target */ > + ret = -ENOTTY; > + if (dm_table_get_num_targets(table) != 1) > + goto out; > + ti = dm_table_get_target(table, 0); > > - bdput(bdev); > - return r; > + ret = -EINVAL; > + if (!ti->type->iterate_devices) > + goto out; > + > + ret = ti->type->iterate_devices(ti, fn, data); > + if (ret) > + goto out; > + > + ret = 0; > +out: > + dm_put_live_table(md, srcu_idx); > + return ret; > +} > + > +/* > + * For register / unregister we need to manually call out to every path. > + */ > +static int __dm_pr_register(struct dm_target *ti, struct dm_dev *dev, > + sector_t start, sector_t len, void *data) > +{ > + struct dm_pr *pr = data; > + const struct pr_ops *ops = dev->bdev->bd_disk->fops->pr_ops; > + > + if (!ops || !ops->pr_register) > + return -EOPNOTSUPP; > + return ops->pr_register(dev->bdev, pr->old_key, pr->new_key, pr->flags); > +} > + > +static int dm_pr_register(struct block_device *bdev, u64 old_key, u64 > new_key, > + u32 flags) > +{ > + struct dm_pr pr = { > + .old_key = old_key, > + .new_key = new_key, > + .flags = flags, > + .fail_early = true, > + }; > + int ret; > + > + ret = dm_call_pr(bdev, __dm_pr_register, &pr); > + if (ret && new_key) { > + /* unregister all paths if we failed to register any path */ > + pr.old_key = new_key; > + pr.new_key = 0; > + pr.flags = 0; > + pr.fail_early = false; > + dm_call_pr(bdev, __dm_pr_register, &pr); > + } > + > + return ret; > } > > static int dm_pr_reserve(struct block_device *bdev, u64 key, enum pr_type > type, >
Reviewed-by: Mike Christie <[email protected]> -- dm-devel mailing list [email protected] https://www.redhat.com/mailman/listinfo/dm-devel
