scsi: target: core: De-RCU of se_lun and se_lun acl

se_lun and se_lun_acl are immutable pointers of struct se_dev_entry.
Remove RCU usage for access to those pointers.

Link: https://lore.kernel.org/r/20220727214125.19647-3-d.bogdanov@yadro.com
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Dmitry Bogdanov <d.bogdanov@yadro.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
This commit is contained in:
Dmitry Bogdanov 2022-07-28 00:41:25 +03:00 committed by Martin K. Petersen
parent dd0a66ada0
commit ef4f7e4bf1
6 changed files with 27 additions and 49 deletions

View File

@ -934,8 +934,7 @@ static void core_alua_queue_state_change_ua(struct t10_alua_tg_pt_gp *tg_pt_gp)
spin_lock(&lun->lun_deve_lock);
list_for_each_entry(se_deve, &lun->lun_deve_list, lun_link) {
lacl = rcu_dereference_check(se_deve->se_lun_acl,
lockdep_is_held(&lun->lun_deve_lock));
lacl = se_deve->se_lun_acl;
/*
* spc4r37 p.242:

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@ -75,7 +75,7 @@ transport_lookup_cmd_lun(struct se_cmd *se_cmd)
return TCM_WRITE_PROTECTED;
}
se_lun = rcu_dereference(deve->se_lun);
se_lun = deve->se_lun;
if (!percpu_ref_tryget_live(&se_lun->lun_ref)) {
se_lun = NULL;
@ -152,7 +152,7 @@ int transport_lookup_tmr_lun(struct se_cmd *se_cmd)
rcu_read_lock();
deve = target_nacl_find_deve(nacl, se_cmd->orig_fe_lun);
if (deve) {
se_lun = rcu_dereference(deve->se_lun);
se_lun = deve->se_lun;
if (!percpu_ref_tryget_live(&se_lun->lun_ref)) {
se_lun = NULL;
@ -216,7 +216,7 @@ struct se_dev_entry *core_get_se_deve_from_rtpi(
rcu_read_lock();
hlist_for_each_entry_rcu(deve, &nacl->lun_entry_hlist, link) {
lun = rcu_dereference(deve->se_lun);
lun = deve->se_lun;
if (!lun) {
pr_err("%s device entries device pointer is"
" NULL, but Initiator has access.\n",
@ -243,11 +243,8 @@ void core_free_device_list_for_node(
struct se_dev_entry *deve;
mutex_lock(&nacl->lun_entry_mutex);
hlist_for_each_entry_rcu(deve, &nacl->lun_entry_hlist, link) {
struct se_lun *lun = rcu_dereference_check(deve->se_lun,
lockdep_is_held(&nacl->lun_entry_mutex));
core_disable_device_list_for_node(lun, deve, nacl, tpg);
}
hlist_for_each_entry_rcu(deve, &nacl->lun_entry_hlist, link)
core_disable_device_list_for_node(deve->se_lun, deve, nacl, tpg);
mutex_unlock(&nacl->lun_entry_mutex);
}
@ -334,8 +331,7 @@ int core_enable_device_list_for_node(
mutex_lock(&nacl->lun_entry_mutex);
orig = target_nacl_find_deve(nacl, mapped_lun);
if (orig && orig->se_lun) {
struct se_lun *orig_lun = rcu_dereference_check(orig->se_lun,
lockdep_is_held(&nacl->lun_entry_mutex));
struct se_lun *orig_lun = orig->se_lun;
if (orig_lun != lun) {
pr_err("Existing orig->se_lun doesn't match new lun"
@ -355,8 +351,8 @@ int core_enable_device_list_for_node(
return -EINVAL;
}
rcu_assign_pointer(new->se_lun, lun);
rcu_assign_pointer(new->se_lun_acl, lun_acl);
new->se_lun = lun;
new->se_lun_acl = lun_acl;
hlist_del_rcu(&orig->link);
hlist_add_head_rcu(&new->link, &nacl->lun_entry_hlist);
mutex_unlock(&nacl->lun_entry_mutex);
@ -374,8 +370,8 @@ int core_enable_device_list_for_node(
return 0;
}
rcu_assign_pointer(new->se_lun, lun);
rcu_assign_pointer(new->se_lun_acl, lun_acl);
new->se_lun = lun;
new->se_lun_acl = lun_acl;
hlist_add_head_rcu(&new->link, &nacl->lun_entry_hlist);
mutex_unlock(&nacl->lun_entry_mutex);
@ -454,10 +450,7 @@ void core_clear_lun_from_tpg(struct se_lun *lun, struct se_portal_group *tpg)
mutex_lock(&nacl->lun_entry_mutex);
hlist_for_each_entry_rcu(deve, &nacl->lun_entry_hlist, link) {
struct se_lun *tmp_lun = rcu_dereference_check(deve->se_lun,
lockdep_is_held(&nacl->lun_entry_mutex));
if (lun != tmp_lun)
if (lun != deve->se_lun)
continue;
core_disable_device_list_for_node(lun, deve, nacl, tpg);

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@ -739,8 +739,7 @@ static struct t10_pr_registration *__core_scsi3_alloc_registration(
if (!deve_tmp->se_lun_acl)
continue;
lacl_tmp = rcu_dereference_check(deve_tmp->se_lun_acl,
lockdep_is_held(&lun_tmp->lun_deve_lock));
lacl_tmp = deve_tmp->se_lun_acl;
nacl_tmp = lacl_tmp->se_lun_nacl;
/*
* Skip the matching struct se_node_acl that is allocated
@ -784,8 +783,7 @@ static struct t10_pr_registration *__core_scsi3_alloc_registration(
* the original *pr_reg is processed in
* __core_scsi3_add_registration()
*/
dest_lun = rcu_dereference_check(deve_tmp->se_lun,
kref_read(&deve_tmp->pr_kref) != 0);
dest_lun = deve_tmp->se_lun;
pr_reg_atp = __core_scsi3_do_alloc_registration(dev,
nacl_tmp, dest_lun, deve_tmp,
@ -1437,34 +1435,26 @@ static void core_scsi3_nodeacl_undepend_item(struct se_node_acl *nacl)
static int core_scsi3_lunacl_depend_item(struct se_dev_entry *se_deve)
{
struct se_lun_acl *lun_acl;
/*
* For nacl->dynamic_node_acl=1
*/
lun_acl = rcu_dereference_check(se_deve->se_lun_acl,
kref_read(&se_deve->pr_kref) != 0);
if (!lun_acl)
if (!se_deve->se_lun_acl)
return 0;
return target_depend_item(&lun_acl->se_lun_group.cg_item);
return target_depend_item(&se_deve->se_lun_acl->se_lun_group.cg_item);
}
static void core_scsi3_lunacl_undepend_item(struct se_dev_entry *se_deve)
{
struct se_lun_acl *lun_acl;
/*
* For nacl->dynamic_node_acl=1
*/
lun_acl = rcu_dereference_check(se_deve->se_lun_acl,
kref_read(&se_deve->pr_kref) != 0);
if (!lun_acl) {
if (!se_deve->se_lun_acl) {
kref_put(&se_deve->pr_kref, target_pr_kref_release);
return;
}
target_undepend_item(&lun_acl->se_lun_group.cg_item);
target_undepend_item(&se_deve->se_lun_acl->se_lun_group.cg_item);
kref_put(&se_deve->pr_kref, target_pr_kref_release);
}
@ -1751,8 +1741,7 @@ core_scsi3_decode_spec_i_port(
* and then call __core_scsi3_add_registration() in the
* 2nd loop which will never fail.
*/
dest_lun = rcu_dereference_check(dest_se_deve->se_lun,
kref_read(&dest_se_deve->pr_kref) != 0);
dest_lun = dest_se_deve->se_lun;
dest_pr_reg = __core_scsi3_alloc_registration(cmd->se_dev,
dest_node_acl, dest_lun, dest_se_deve,
@ -3446,8 +3435,7 @@ after_iport_check:
dest_pr_reg = __core_scsi3_locate_pr_reg(dev, dest_node_acl,
iport_ptr);
if (!dest_pr_reg) {
struct se_lun *dest_lun = rcu_dereference_check(dest_se_deve->se_lun,
kref_read(&dest_se_deve->pr_kref) != 0);
struct se_lun *dest_lun = dest_se_deve->se_lun;
spin_unlock(&dev->dev_reservation_lock);
if (core_scsi3_alloc_registration(cmd->se_dev, dest_node_acl,

View File

@ -877,7 +877,6 @@ static ssize_t target_stat_auth_dev_show(struct config_item *item,
struct se_lun_acl *lacl = auth_to_lacl(item);
struct se_node_acl *nacl = lacl->se_lun_nacl;
struct se_dev_entry *deve;
struct se_lun *lun;
ssize_t ret;
rcu_read_lock();
@ -886,9 +885,9 @@ static ssize_t target_stat_auth_dev_show(struct config_item *item,
rcu_read_unlock();
return -ENODEV;
}
lun = rcu_dereference(deve->se_lun);
/* scsiDeviceIndex */
ret = snprintf(page, PAGE_SIZE, "%u\n", lun->lun_index);
ret = snprintf(page, PAGE_SIZE, "%u\n", deve->se_lun->lun_index);
rcu_read_unlock();
return ret;
}
@ -1217,7 +1216,6 @@ static ssize_t target_stat_iport_dev_show(struct config_item *item,
struct se_lun_acl *lacl = iport_to_lacl(item);
struct se_node_acl *nacl = lacl->se_lun_nacl;
struct se_dev_entry *deve;
struct se_lun *lun;
ssize_t ret;
rcu_read_lock();
@ -1226,9 +1224,9 @@ static ssize_t target_stat_iport_dev_show(struct config_item *item,
rcu_read_unlock();
return -ENODEV;
}
lun = rcu_dereference(deve->se_lun);
/* scsiDeviceIndex */
ret = snprintf(page, PAGE_SIZE, "%u\n", lun->lun_index);
ret = snprintf(page, PAGE_SIZE, "%u\n", deve->se_lun->lun_index);
rcu_read_unlock();
return ret;
}

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@ -88,7 +88,7 @@ static int target_xcopy_locate_se_dev_e4(struct se_session *sess,
struct se_device *this_dev;
int rc;
this_lun = rcu_dereference(deve->se_lun);
this_lun = deve->se_lun;
this_dev = rcu_dereference_raw(this_lun->lun_se_dev);
rc = target_xcopy_locate_se_dev_e4_iter(this_dev, dev_wwn);

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@ -665,9 +665,9 @@ struct se_dev_entry {
/* Used for PR SPEC_I_PT=1 and REGISTER_AND_MOVE */
struct kref pr_kref;
struct completion pr_comp;
struct se_lun_acl __rcu *se_lun_acl;
struct se_lun_acl *se_lun_acl;
spinlock_t ua_lock;
struct se_lun __rcu *se_lun;
struct se_lun *se_lun;
#define DEF_PR_REG_ACTIVE 1
unsigned long deve_flags;
struct list_head alua_port_list;