devlink: hold the instance lock during eswitch_mode callbacks

Make the devlink core hold the instance lock during eswitch_mode
callbacks. Cheat in case of mlx5 (see the cover letter).

Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Jakub Kicinski 2022-03-18 12:23:44 -07:00 committed by David S. Miller
parent aff3a92509
commit 14e426bf1a
5 changed files with 54 additions and 51 deletions

View File

@ -559,44 +559,34 @@ int bnxt_dl_eswitch_mode_set(struct devlink *devlink, u16 mode,
struct netlink_ext_ack *extack)
{
struct bnxt *bp = bnxt_get_bp_from_dl(devlink);
int rc = 0;
devl_lock(devlink);
if (bp->eswitch_mode == mode) {
netdev_info(bp->dev, "already in %s eswitch mode\n",
mode == DEVLINK_ESWITCH_MODE_LEGACY ?
"legacy" : "switchdev");
rc = -EINVAL;
goto done;
return -EINVAL;
}
switch (mode) {
case DEVLINK_ESWITCH_MODE_LEGACY:
bnxt_vf_reps_destroy(bp);
break;
return 0;
case DEVLINK_ESWITCH_MODE_SWITCHDEV:
if (bp->hwrm_spec_code < 0x10803) {
netdev_warn(bp->dev, "FW does not support SRIOV E-Switch SWITCHDEV mode\n");
rc = -ENOTSUPP;
goto done;
return -ENOTSUPP;
}
if (pci_num_vf(bp->pdev) == 0) {
netdev_info(bp->dev, "Enable VFs before setting switchdev mode\n");
rc = -EPERM;
goto done;
return -EPERM;
}
rc = bnxt_vf_reps_create(bp);
break;
return bnxt_vf_reps_create(bp);
default:
rc = -EINVAL;
goto done;
return -EINVAL;
}
done:
devl_unlock(devlink);
return rc;
}
#endif

View File

@ -3337,6 +3337,27 @@ static int eswitch_devlink_esw_mode_check(const struct mlx5_eswitch *esw)
!mlx5_core_is_ecpf_esw_manager(esw->dev)) ? -EOPNOTSUPP : 0;
}
/* FIXME: devl_unlock() followed by devl_lock() inside driver callback
* is never correct and prone to races. It's a transitional workaround,
* never repeat this pattern.
*
* This code MUST be fixed before removing devlink_mutex as it is safe
* to do only because of that mutex.
*/
static void mlx5_eswtich_mode_callback_enter(struct devlink *devlink,
struct mlx5_eswitch *esw)
{
devl_unlock(devlink);
down_write(&esw->mode_lock);
}
static void mlx5_eswtich_mode_callback_exit(struct devlink *devlink,
struct mlx5_eswitch *esw)
{
up_write(&esw->mode_lock);
devl_lock(devlink);
}
int mlx5_devlink_eswitch_mode_set(struct devlink *devlink, u16 mode,
struct netlink_ext_ack *extack)
{
@ -3351,6 +3372,15 @@ int mlx5_devlink_eswitch_mode_set(struct devlink *devlink, u16 mode,
if (esw_mode_from_devlink(mode, &mlx5_mode))
return -EINVAL;
/* FIXME: devl_unlock() followed by devl_lock() inside driver callback
* is never correct and prone to races. It's a transitional workaround,
* never repeat this pattern.
*
* This code MUST be fixed before removing devlink_mutex as it is safe
* to do only because of that mutex.
*/
devl_unlock(devlink);
mlx5_lag_disable_change(esw->dev);
err = mlx5_esw_try_lock(esw);
if (err < 0) {
@ -3381,6 +3411,7 @@ unlock:
mlx5_esw_unlock(esw);
enable_lag:
mlx5_lag_enable_change(esw->dev);
devl_lock(devlink);
return err;
}
@ -3393,14 +3424,14 @@ int mlx5_devlink_eswitch_mode_get(struct devlink *devlink, u16 *mode)
if (IS_ERR(esw))
return PTR_ERR(esw);
down_write(&esw->mode_lock);
mlx5_eswtich_mode_callback_enter(devlink, esw);
err = eswitch_devlink_esw_mode_check(esw);
if (err)
goto unlock;
err = esw_mode_to_devlink(esw->mode, mode);
unlock:
up_write(&esw->mode_lock);
mlx5_eswtich_mode_callback_exit(devlink, esw);
return err;
}
@ -3447,7 +3478,7 @@ int mlx5_devlink_eswitch_inline_mode_set(struct devlink *devlink, u8 mode,
if (IS_ERR(esw))
return PTR_ERR(esw);
down_write(&esw->mode_lock);
mlx5_eswtich_mode_callback_enter(devlink, esw);
err = eswitch_devlink_esw_mode_check(esw);
if (err)
goto out;
@ -3484,11 +3515,11 @@ int mlx5_devlink_eswitch_inline_mode_set(struct devlink *devlink, u8 mode,
goto out;
esw->offloads.inline_mode = mlx5_mode;
up_write(&esw->mode_lock);
mlx5_eswtich_mode_callback_exit(devlink, esw);
return 0;
out:
up_write(&esw->mode_lock);
mlx5_eswtich_mode_callback_exit(devlink, esw);
return err;
}
@ -3501,14 +3532,14 @@ int mlx5_devlink_eswitch_inline_mode_get(struct devlink *devlink, u8 *mode)
if (IS_ERR(esw))
return PTR_ERR(esw);
down_write(&esw->mode_lock);
mlx5_eswtich_mode_callback_enter(devlink, esw);
err = eswitch_devlink_esw_mode_check(esw);
if (err)
goto unlock;
err = esw_inline_mode_to_devlink(esw->offloads.inline_mode, mode);
unlock:
up_write(&esw->mode_lock);
mlx5_eswtich_mode_callback_exit(devlink, esw);
return err;
}
@ -3524,7 +3555,7 @@ int mlx5_devlink_eswitch_encap_mode_set(struct devlink *devlink,
if (IS_ERR(esw))
return PTR_ERR(esw);
down_write(&esw->mode_lock);
mlx5_eswtich_mode_callback_enter(devlink, esw);
err = eswitch_devlink_esw_mode_check(esw);
if (err)
goto unlock;
@ -3570,7 +3601,7 @@ int mlx5_devlink_eswitch_encap_mode_set(struct devlink *devlink,
}
unlock:
up_write(&esw->mode_lock);
mlx5_eswtich_mode_callback_exit(devlink, esw);
return err;
}
@ -3584,15 +3615,14 @@ int mlx5_devlink_eswitch_encap_mode_get(struct devlink *devlink,
if (IS_ERR(esw))
return PTR_ERR(esw);
down_write(&esw->mode_lock);
mlx5_eswtich_mode_callback_enter(devlink, esw);
err = eswitch_devlink_esw_mode_check(esw);
if (err)
goto unlock;
*encap = esw->offloads.encap;
unlock:
up_write(&esw->mode_lock);
mlx5_eswtich_mode_callback_exit(devlink, esw);
return err;
}

View File

@ -144,13 +144,8 @@ static int nfp_devlink_eswitch_mode_set(struct devlink *devlink, u16 mode,
struct netlink_ext_ack *extack)
{
struct nfp_pf *pf = devlink_priv(devlink);
int ret;
devl_lock(devlink);
ret = nfp_app_eswitch_mode_set(pf->app, mode);
devl_unlock(devlink);
return ret;
return nfp_app_eswitch_mode_set(pf->app, mode);
}
static const struct nfp_devlink_versions_simple {

View File

@ -615,22 +615,16 @@ static int nsim_devlink_eswitch_mode_set(struct devlink *devlink, u16 mode,
struct netlink_ext_ack *extack)
{
struct nsim_dev *nsim_dev = devlink_priv(devlink);
int err = 0;
devl_lock(devlink);
if (mode == nsim_dev->esw_mode)
goto unlock;
return 0;
if (mode == DEVLINK_ESWITCH_MODE_LEGACY)
err = nsim_esw_legacy_enable(nsim_dev, extack);
else if (mode == DEVLINK_ESWITCH_MODE_SWITCHDEV)
err = nsim_esw_switchdev_enable(nsim_dev, extack);
else
err = -EINVAL;
return nsim_esw_legacy_enable(nsim_dev, extack);
if (mode == DEVLINK_ESWITCH_MODE_SWITCHDEV)
return nsim_esw_switchdev_enable(nsim_dev, extack);
unlock:
devl_unlock(devlink);
return err;
return -EINVAL;
}
static int nsim_devlink_eswitch_mode_get(struct devlink *devlink, u16 *mode)

View File

@ -2868,15 +2868,11 @@ static int devlink_rate_nodes_check(struct devlink *devlink, u16 mode,
{
struct devlink_rate *devlink_rate;
/* Take the lock to sync with destroy */
mutex_lock(&devlink->lock);
list_for_each_entry(devlink_rate, &devlink->rate_list, list)
if (devlink_rate_is_node(devlink_rate)) {
mutex_unlock(&devlink->lock);
NL_SET_ERR_MSG_MOD(extack, "Rate node(s) exists.");
return -EBUSY;
}
mutex_unlock(&devlink->lock);
return 0;
}
@ -8735,14 +8731,12 @@ static const struct genl_small_ops devlink_nl_ops[] = {
.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
.doit = devlink_nl_cmd_eswitch_get_doit,
.flags = GENL_ADMIN_PERM,
.internal_flags = DEVLINK_NL_FLAG_NO_LOCK,
},
{
.cmd = DEVLINK_CMD_ESWITCH_SET,
.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
.doit = devlink_nl_cmd_eswitch_set_doit,
.flags = GENL_ADMIN_PERM,
.internal_flags = DEVLINK_NL_FLAG_NO_LOCK,
},
{
.cmd = DEVLINK_CMD_DPIPE_TABLE_GET,