Acked-by: Jon Derrick <jonathan.derrick@xxxxxxxxx>
On Thu, 2019-02-14 at 01:16 +0100, David Kozub wrote:
> The steps argument is only read by the next function, so it can
> be passed directly as an argument rather than via opal_dev.
>
> Normally, the steps is an array on the stack, so the pointer stops
> being valid then the function that set opal_dev.steps returns.
> If opal_dev.steps was not set to NULL before return it would become
> a dangling pointer. When the steps are passed as argument this
> becomes easier to see and more difficult to misuse.
>
> Signed-off-by: David Kozub <zub@xxxxxxxxxxxxxxxxxx>
> ---
> block/sed-opal.c | 158 +++++++++++++++++++++----------------------
> ----
> 1 file changed, 69 insertions(+), 89 deletions(-)
>
> diff --git a/block/sed-opal.c b/block/sed-opal.c
> index be0d633783c8..f027c0cb682e 100644
> --- a/block/sed-opal.c
> +++ b/block/sed-opal.c
> @@ -85,7 +85,6 @@ struct opal_dev {
> void *data;
> sec_send_recv *send_recv;
>
> - const struct opal_step *steps;
> struct mutex dev_lock;
> u16 comid;
> u32 hsn;
> @@ -382,37 +381,34 @@ static void check_geometry(struct opal_dev
> *dev, const void *data)
> dev->lowest_lba = geo->lowest_aligned_lba;
> }
>
> -static int next(struct opal_dev *dev)
> +static int next(struct opal_dev *dev, const struct opal_step *steps,
> + size_t n_steps)
> {
> const struct opal_step *step;
> - int state = 0, error = 0;
> + size_t state;
> + int error = 0;
>
> - do {
> - step = &dev->steps[state];
> - if (!step->fn)
> - break;
> + for (state = 0; state < n_steps; state++) {
> + step = &steps[state];
>
> error = step->fn(dev, step->data);
> - if (error) {
> - pr_debug("Step %d (%pS) failed with error %d:
> %s\n",
> - state, step->fn, error,
> - opal_error_to_human(error));
> -
> - /* For each OPAL command we do a discovery0
> then we
> - * start some sort of session.
> - * If we haven't passed state 1 then there was
> an error
> - * on discovery0 or during the attempt to start
> a
> - * session. Therefore we shouldn't attempt to
> terminate
> - * a session, as one has not yet been created.
> - */
> - if (state > 1) {
> - end_opal_session_error(dev);
> - return error;
> - }
> + if (error)
> + goto out_error;
> + }
>
> - }
> - state++;
> - } while (!error);
> + return 0;
> +
> +out_error:
> + /*
> + * For each OPAL command the first step in steps does a
> discovery0
> + * and the second step starts some sort of session. If an error
> occurred
> + * in the first two steps (and thus stopping the loop with
> state <= 1)
> + * then there was an error before or during the attempt to
> start a
> + * session. Therefore we shouldn't attempt to terminate a
> session, as
> + * one has not yet been created.
> + */
> + if (state > 1)
> + end_opal_session_error(dev);
>
> return error;
> }
> @@ -1836,17 +1832,13 @@ static int end_opal_session(struct opal_dev
> *dev, void *data)
> static int end_opal_session_error(struct opal_dev *dev)
> {
> const struct opal_step error_end_session[] = {
> - { end_opal_session, },
> - { NULL, }
> + { end_opal_session, }
> };
> - dev->steps = error_end_session;
> - return next(dev);
> + return next(dev, error_end_session,
> ARRAY_SIZE(error_end_session));
> }
>
> -static inline void setup_opal_dev(struct opal_dev *dev,
> - const struct opal_step *steps)
> +static inline void setup_opal_dev(struct opal_dev *dev)
> {
> - dev->steps = steps;
> dev->tsn = 0;
> dev->hsn = 0;
> dev->prev_data = NULL;
> @@ -1855,14 +1847,13 @@ static inline void setup_opal_dev(struct
> opal_dev *dev,
> static int check_opal_support(struct opal_dev *dev)
> {
> const struct opal_step steps[] = {
> - { opal_discovery0, },
> - { NULL, }
> + { opal_discovery0, }
> };
> int ret;
>
> mutex_lock(&dev->dev_lock);
> - setup_opal_dev(dev, steps);
> - ret = next(dev);
> + setup_opal_dev(dev);
> + ret = next(dev, steps, ARRAY_SIZE(steps));
> dev->supported = !ret;
> mutex_unlock(&dev->dev_lock);
> return ret;
> @@ -1919,14 +1910,13 @@ static int
> opal_secure_erase_locking_range(struct opal_dev *dev,
> { start_auth_opal_session, opal_session },
> { get_active_key, &opal_session->opal_key.lr },
> { gen_key, },
> - { end_opal_session, },
> - { NULL, }
> + { end_opal_session, }
> };
> int ret;
>
> mutex_lock(&dev->dev_lock);
> - setup_opal_dev(dev, erase_steps);
> - ret = next(dev);
> + setup_opal_dev(dev);
> + ret = next(dev, erase_steps, ARRAY_SIZE(erase_steps));
> mutex_unlock(&dev->dev_lock);
> return ret;
> }
> @@ -1938,14 +1928,13 @@ static int opal_erase_locking_range(struct
> opal_dev *dev,
> { opal_discovery0, },
> { start_auth_opal_session, opal_session },
> { erase_locking_range, opal_session },
> - { end_opal_session, },
> - { NULL, }
> + { end_opal_session, }
> };
> int ret;
>
> mutex_lock(&dev->dev_lock);
> - setup_opal_dev(dev, erase_steps);
> - ret = next(dev);
> + setup_opal_dev(dev);
> + ret = next(dev, erase_steps, ARRAY_SIZE(erase_steps));
> mutex_unlock(&dev->dev_lock);
> return ret;
> }
> @@ -1963,8 +1952,7 @@ static int
> opal_enable_disable_shadow_mbr(struct opal_dev *dev,
> { end_opal_session, },
> { start_admin1LSP_opal_session, &opal_mbr->key },
> { set_mbr_enable_disable, &enable_disable },
> - { end_opal_session, },
> - { NULL, }
> + { end_opal_session, }
> };
> int ret;
>
> @@ -1973,8 +1961,8 @@ static int
> opal_enable_disable_shadow_mbr(struct opal_dev *dev,
> return -EINVAL;
>
> mutex_lock(&dev->dev_lock);
> - setup_opal_dev(dev, mbr_steps);
> - ret = next(dev);
> + setup_opal_dev(dev);
> + ret = next(dev, mbr_steps, ARRAY_SIZE(mbr_steps));
> mutex_unlock(&dev->dev_lock);
> return ret;
> }
> @@ -1991,7 +1979,7 @@ static int opal_save(struct opal_dev *dev,
> struct opal_lock_unlock *lk_unlk)
> suspend->lr = lk_unlk->session.opal_key.lr;
>
> mutex_lock(&dev->dev_lock);
> - setup_opal_dev(dev, NULL);
> + setup_opal_dev(dev);
> add_suspend_info(dev, suspend);
> mutex_unlock(&dev->dev_lock);
> return 0;
> @@ -2004,8 +1992,7 @@ static int opal_add_user_to_lr(struct opal_dev
> *dev,
> { opal_discovery0, },
> { start_admin1LSP_opal_session, &lk_unlk-
> >session.opal_key },
> { add_user_to_lr, lk_unlk },
> - { end_opal_session, },
> - { NULL, }
> + { end_opal_session, }
> };
> int ret;
>
> @@ -2027,8 +2014,8 @@ static int opal_add_user_to_lr(struct opal_dev
> *dev,
> }
>
> mutex_lock(&dev->dev_lock);
> - setup_opal_dev(dev, steps);
> - ret = next(dev);
> + setup_opal_dev(dev);
> + ret = next(dev, steps, ARRAY_SIZE(steps));
> mutex_unlock(&dev->dev_lock);
> return ret;
> }
> @@ -2038,14 +2025,13 @@ static int opal_reverttper(struct opal_dev
> *dev, struct opal_key *opal)
> const struct opal_step revert_steps[] = {
> { opal_discovery0, },
> { start_SIDASP_opal_session, opal },
> - { revert_tper, }, /* controller will terminate session
> */
> - { NULL, }
> + { revert_tper, } /* controller will terminate session
> */
> };
> int ret;
>
> mutex_lock(&dev->dev_lock);
> - setup_opal_dev(dev, revert_steps);
> - ret = next(dev);
> + setup_opal_dev(dev);
> + ret = next(dev, revert_steps, ARRAY_SIZE(revert_steps));
> mutex_unlock(&dev->dev_lock);
>
> /*
> @@ -2065,19 +2051,20 @@ static int __opal_lock_unlock(struct opal_dev
> *dev,
> { opal_discovery0, },
> { start_auth_opal_session, &lk_unlk->session },
> { lock_unlock_locking_range, lk_unlk },
> - { end_opal_session, },
> - { NULL, }
> + { end_opal_session, }
> };
> const struct opal_step unlock_sum_steps[] = {
> { opal_discovery0, },
> { start_auth_opal_session, &lk_unlk->session },
> { lock_unlock_locking_range_sum, lk_unlk },
> - { end_opal_session, },
> - { NULL, }
> + { end_opal_session, }
> };
>
> - dev->steps = lk_unlk->session.sum ? unlock_sum_steps :
> unlock_steps;
> - return next(dev);
> + if (lk_unlk->session.sum)
> + return next(dev, unlock_sum_steps,
> + ARRAY_SIZE(unlock_sum_steps));
> + else
> + return next(dev, unlock_steps,
> ARRAY_SIZE(unlock_steps));
> }
>
> static int __opal_set_mbr_done(struct opal_dev *dev, struct opal_key
> *key)
> @@ -2087,12 +2074,10 @@ static int __opal_set_mbr_done(struct
> opal_dev *dev, struct opal_key *key)
> { opal_discovery0, },
> { start_admin1LSP_opal_session, key },
> { set_mbr_done, &mbr_done_tf },
> - { end_opal_session, },
> - { NULL, }
> + { end_opal_session, }
> };
>
> - dev->steps = mbrdone_step;
> - return next(dev);
> + return next(dev, mbrdone_step, ARRAY_SIZE(mbrdone_step));
> }
>
> static int opal_lock_unlock(struct opal_dev *dev,
> @@ -2119,8 +2104,7 @@ static int opal_take_ownership(struct opal_dev
> *dev, struct opal_key *opal)
> { end_opal_session, },
> { start_SIDASP_opal_session, opal },
> { set_sid_cpin_pin, opal },
> - { end_opal_session, },
> - { NULL, }
> + { end_opal_session, }
> };
> int ret;
>
> @@ -2128,8 +2112,8 @@ static int opal_take_ownership(struct opal_dev
> *dev, struct opal_key *opal)
> return -ENODEV;
>
> mutex_lock(&dev->dev_lock);
> - setup_opal_dev(dev, owner_steps);
> - ret = next(dev);
> + setup_opal_dev(dev);
> + ret = next(dev, owner_steps, ARRAY_SIZE(owner_steps));
> mutex_unlock(&dev->dev_lock);
> return ret;
> }
> @@ -2142,8 +2126,7 @@ static int opal_activate_lsp(struct opal_dev
> *dev,
> { start_SIDASP_opal_session, &opal_lr_act->key },
> { get_lsp_lifecycle, },
> { activate_lsp, opal_lr_act },
> - { end_opal_session, },
> - { NULL, }
> + { end_opal_session, }
> };
> int ret;
>
> @@ -2151,8 +2134,8 @@ static int opal_activate_lsp(struct opal_dev
> *dev,
> return -EINVAL;
>
> mutex_lock(&dev->dev_lock);
> - setup_opal_dev(dev, active_steps);
> - ret = next(dev);
> + setup_opal_dev(dev);
> + ret = next(dev, active_steps, ARRAY_SIZE(active_steps));
> mutex_unlock(&dev->dev_lock);
> return ret;
> }
> @@ -2164,14 +2147,13 @@ static int opal_setup_locking_range(struct
> opal_dev *dev,
> { opal_discovery0, },
> { start_auth_opal_session, &opal_lrs->session },
> { setup_locking_range, opal_lrs },
> - { end_opal_session, },
> - { NULL, }
> + { end_opal_session, }
> };
> int ret;
>
> mutex_lock(&dev->dev_lock);
> - setup_opal_dev(dev, lr_steps);
> - ret = next(dev);
> + setup_opal_dev(dev);
> + ret = next(dev, lr_steps, ARRAY_SIZE(lr_steps));
> mutex_unlock(&dev->dev_lock);
> return ret;
> }
> @@ -2182,8 +2164,7 @@ static int opal_set_new_pw(struct opal_dev
> *dev, struct opal_new_pw *opal_pw)
> { opal_discovery0, },
> { start_auth_opal_session, &opal_pw->session },
> { set_new_pw, &opal_pw->new_user_pw },
> - { end_opal_session, },
> - { NULL }
> + { end_opal_session, }
> };
> int ret;
>
> @@ -2194,8 +2175,8 @@ static int opal_set_new_pw(struct opal_dev
> *dev, struct opal_new_pw *opal_pw)
> return -EINVAL;
>
> mutex_lock(&dev->dev_lock);
> - setup_opal_dev(dev, pw_steps);
> - ret = next(dev);
> + setup_opal_dev(dev);
> + ret = next(dev, pw_steps, ARRAY_SIZE(pw_steps));
> mutex_unlock(&dev->dev_lock);
> return ret;
> }
> @@ -2207,8 +2188,7 @@ static int opal_activate_user(struct opal_dev
> *dev,
> { opal_discovery0, },
> { start_admin1LSP_opal_session, &opal_session->opal_key
> },
> { internal_activate_user, opal_session },
> - { end_opal_session, },
> - { NULL, }
> + { end_opal_session, }
> };
> int ret;
>
> @@ -2220,8 +2200,8 @@ static int opal_activate_user(struct opal_dev
> *dev,
> }
>
> mutex_lock(&dev->dev_lock);
> - setup_opal_dev(dev, act_steps);
> - ret = next(dev);
> + setup_opal_dev(dev);
> + ret = next(dev, act_steps, ARRAY_SIZE(act_steps));
> mutex_unlock(&dev->dev_lock);
> return ret;
> }
> @@ -2238,7 +2218,7 @@ bool opal_unlock_from_suspend(struct opal_dev
> *dev)
> return false;
>
> mutex_lock(&dev->dev_lock);
> - setup_opal_dev(dev, NULL);
> + setup_opal_dev(dev);
>
> list_for_each_entry(suspend, &dev->unlk_lst, node) {
> dev->tsn = 0;
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