diff --git a/include/linux/mmu_notifier.h b/include/linux/mmu_notifier.h index a302925fbc61..4342fa75dc24 100644 --- a/include/linux/mmu_notifier.h +++ b/include/linux/mmu_notifier.h @@ -73,7 +73,7 @@ struct mmu_notifier_ops { * through the gart alias address, so leading to memory * corruption. */ - void (*release)(struct mmu_notifier *mn, + void (*release)(struct mmu_notifier *subscription, struct mm_struct *mm); /* @@ -85,7 +85,7 @@ struct mmu_notifier_ops { * Start-end is necessary in case the secondary MMU is mapping the page * at a smaller granularity than the primary MMU. */ - int (*clear_flush_young)(struct mmu_notifier *mn, + int (*clear_flush_young)(struct mmu_notifier *subscription, struct mm_struct *mm, unsigned long start, unsigned long end); @@ -95,7 +95,7 @@ struct mmu_notifier_ops { * latter, it is supposed to test-and-clear the young/accessed bitflag * in the secondary pte, but it may omit flushing the secondary tlb. */ - int (*clear_young)(struct mmu_notifier *mn, + int (*clear_young)(struct mmu_notifier *subscription, struct mm_struct *mm, unsigned long start, unsigned long end); @@ -106,7 +106,7 @@ struct mmu_notifier_ops { * frequently used without actually clearing the flag or tearing * down the secondary mapping on the page. */ - int (*test_young)(struct mmu_notifier *mn, + int (*test_young)(struct mmu_notifier *subscription, struct mm_struct *mm, unsigned long address); @@ -114,7 +114,7 @@ struct mmu_notifier_ops { * change_pte is called in cases that pte mapping to page is changed: * for example, when ksm remaps pte to point to a new shared page. */ - void (*change_pte)(struct mmu_notifier *mn, + void (*change_pte)(struct mmu_notifier *subscription, struct mm_struct *mm, unsigned long address, pte_t pte); @@ -169,9 +169,9 @@ struct mmu_notifier_ops { * invalidate_range_end. * */ - int (*invalidate_range_start)(struct mmu_notifier *mn, + int (*invalidate_range_start)(struct mmu_notifier *subscription, const struct mmu_notifier_range *range); - void (*invalidate_range_end)(struct mmu_notifier *mn, + void (*invalidate_range_end)(struct mmu_notifier *subscription, const struct mmu_notifier_range *range); /* @@ -192,8 +192,10 @@ struct mmu_notifier_ops { * of what was passed to invalidate_range_start()/end(), if * called between those functions. */ - void (*invalidate_range)(struct mmu_notifier *mn, struct mm_struct *mm, - unsigned long start, unsigned long end); + void (*invalidate_range)(struct mmu_notifier *subscription, + struct mm_struct *mm, + unsigned long start, + unsigned long end); /* * These callbacks are used with the get/put interface to manage the @@ -206,7 +208,7 @@ struct mmu_notifier_ops { * and cannot sleep. */ struct mmu_notifier *(*alloc_notifier)(struct mm_struct *mm); - void (*free_notifier)(struct mmu_notifier *mn); + void (*free_notifier)(struct mmu_notifier *subscription); }; /* @@ -280,14 +282,14 @@ mmu_notifier_get(const struct mmu_notifier_ops *ops, struct mm_struct *mm) up_write(&mm->mmap_sem); return ret; } -void mmu_notifier_put(struct mmu_notifier *mn); +void mmu_notifier_put(struct mmu_notifier *subscription); void mmu_notifier_synchronize(void); -extern int mmu_notifier_register(struct mmu_notifier *mn, +extern int mmu_notifier_register(struct mmu_notifier *subscription, struct mm_struct *mm); -extern int __mmu_notifier_register(struct mmu_notifier *mn, +extern int __mmu_notifier_register(struct mmu_notifier *subscription, struct mm_struct *mm); -extern void mmu_notifier_unregister(struct mmu_notifier *mn, +extern void mmu_notifier_unregister(struct mmu_notifier *subscription, struct mm_struct *mm); unsigned long mmu_interval_read_begin(struct mmu_interval_notifier *mni); diff --git a/mm/mmu_notifier.c b/mm/mmu_notifier.c index a409abfb9f26..12b35d8b444a 100644 --- a/mm/mmu_notifier.c +++ b/mm/mmu_notifier.c @@ -294,7 +294,7 @@ static void mn_itree_release(struct mmu_notifier_subscriptions *subscriptions, static void mn_hlist_release(struct mmu_notifier_subscriptions *subscriptions, struct mm_struct *mm) { - struct mmu_notifier *mn; + struct mmu_notifier *subscription; int id; /* @@ -302,27 +302,27 @@ static void mn_hlist_release(struct mmu_notifier_subscriptions *subscriptions, * ->release returns. */ id = srcu_read_lock(&srcu); - hlist_for_each_entry_rcu(mn, &subscriptions->list, hlist) + hlist_for_each_entry_rcu(subscription, &subscriptions->list, hlist) /* * If ->release runs before mmu_notifier_unregister it must be * handled, as it's the only way for the driver to flush all * existing sptes and stop the driver from establishing any more * sptes before all the pages in the mm are freed. */ - if (mn->ops->release) - mn->ops->release(mn, mm); + if (subscription->ops->release) + subscription->ops->release(subscription, mm); spin_lock(&subscriptions->lock); while (unlikely(!hlist_empty(&subscriptions->list))) { - mn = hlist_entry(subscriptions->list.first, struct mmu_notifier, - hlist); + subscription = hlist_entry(subscriptions->list.first, + struct mmu_notifier, hlist); /* * We arrived before mmu_notifier_unregister so * mmu_notifier_unregister will do nothing other than to wait * for ->release to finish and for mmu_notifier_unregister to * return. */ - hlist_del_init_rcu(&mn->hlist); + hlist_del_init_rcu(&subscription->hlist); } spin_unlock(&subscriptions->lock); srcu_read_unlock(&srcu, id); @@ -360,13 +360,15 @@ int __mmu_notifier_clear_flush_young(struct mm_struct *mm, unsigned long start, unsigned long end) { - struct mmu_notifier *mn; + struct mmu_notifier *subscription; int young = 0, id; id = srcu_read_lock(&srcu); - hlist_for_each_entry_rcu(mn, &mm->notifier_subscriptions->list, hlist) { - if (mn->ops->clear_flush_young) - young |= mn->ops->clear_flush_young(mn, mm, start, end); + hlist_for_each_entry_rcu(subscription, + &mm->notifier_subscriptions->list, hlist) { + if (subscription->ops->clear_flush_young) + young |= subscription->ops->clear_flush_young( + subscription, mm, start, end); } srcu_read_unlock(&srcu, id); @@ -377,13 +379,15 @@ int __mmu_notifier_clear_young(struct mm_struct *mm, unsigned long start, unsigned long end) { - struct mmu_notifier *mn; + struct mmu_notifier *subscription; int young = 0, id; id = srcu_read_lock(&srcu); - hlist_for_each_entry_rcu(mn, &mm->notifier_subscriptions->list, hlist) { - if (mn->ops->clear_young) - young |= mn->ops->clear_young(mn, mm, start, end); + hlist_for_each_entry_rcu(subscription, + &mm->notifier_subscriptions->list, hlist) { + if (subscription->ops->clear_young) + young |= subscription->ops->clear_young(subscription, + mm, start, end); } srcu_read_unlock(&srcu, id); @@ -393,13 +397,15 @@ int __mmu_notifier_clear_young(struct mm_struct *mm, int __mmu_notifier_test_young(struct mm_struct *mm, unsigned long address) { - struct mmu_notifier *mn; + struct mmu_notifier *subscription; int young = 0, id; id = srcu_read_lock(&srcu); - hlist_for_each_entry_rcu(mn, &mm->notifier_subscriptions->list, hlist) { - if (mn->ops->test_young) { - young = mn->ops->test_young(mn, mm, address); + hlist_for_each_entry_rcu(subscription, + &mm->notifier_subscriptions->list, hlist) { + if (subscription->ops->test_young) { + young = subscription->ops->test_young(subscription, mm, + address); if (young) break; } @@ -412,14 +418,15 @@ int __mmu_notifier_test_young(struct mm_struct *mm, void __mmu_notifier_change_pte(struct mm_struct *mm, unsigned long address, pte_t pte) { - struct mmu_notifier *mn; + struct mmu_notifier *subscription; int id; id = srcu_read_lock(&srcu); - hlist_for_each_entry_rcu(mn, &mm->notifier_subscriptions->list, - hlist) { - if (mn->ops->change_pte) - mn->ops->change_pte(mn, mm, address, pte); + hlist_for_each_entry_rcu(subscription, + &mm->notifier_subscriptions->list, hlist) { + if (subscription->ops->change_pte) + subscription->ops->change_pte(subscription, mm, address, + pte); } srcu_read_unlock(&srcu, id); } @@ -456,24 +463,28 @@ static int mn_hlist_invalidate_range_start( struct mmu_notifier_subscriptions *subscriptions, struct mmu_notifier_range *range) { - struct mmu_notifier *mn; + struct mmu_notifier *subscription; int ret = 0; int id; id = srcu_read_lock(&srcu); - hlist_for_each_entry_rcu(mn, &subscriptions->list, hlist) { - if (mn->ops->invalidate_range_start) { + hlist_for_each_entry_rcu(subscription, &subscriptions->list, hlist) { + const struct mmu_notifier_ops *ops = subscription->ops; + + if (ops->invalidate_range_start) { int _ret; if (!mmu_notifier_range_blockable(range)) non_block_start(); - _ret = mn->ops->invalidate_range_start(mn, range); + _ret = ops->invalidate_range_start(subscription, range); if (!mmu_notifier_range_blockable(range)) non_block_end(); if (_ret) { pr_info("%pS callback failed with %d in %sblockable context.\n", - mn->ops->invalidate_range_start, _ret, - !mmu_notifier_range_blockable(range) ? "non-" : ""); + ops->invalidate_range_start, _ret, + !mmu_notifier_range_blockable(range) ? + "non-" : + ""); WARN_ON(mmu_notifier_range_blockable(range) || _ret != -EAGAIN); ret = _ret; @@ -505,11 +516,11 @@ static void mn_hlist_invalidate_end(struct mmu_notifier_subscriptions *subscriptions, struct mmu_notifier_range *range, bool only_end) { - struct mmu_notifier *mn; + struct mmu_notifier *subscription; int id; id = srcu_read_lock(&srcu); - hlist_for_each_entry_rcu(mn, &subscriptions->list, hlist) { + hlist_for_each_entry_rcu(subscription, &subscriptions->list, hlist) { /* * Call invalidate_range here too to avoid the need for the * subsystem of having to register an invalidate_range_end @@ -523,14 +534,16 @@ mn_hlist_invalidate_end(struct mmu_notifier_subscriptions *subscriptions, * is safe to do when we know that a call to invalidate_range() * already happen under page table lock. */ - if (!only_end && mn->ops->invalidate_range) - mn->ops->invalidate_range(mn, range->mm, - range->start, - range->end); - if (mn->ops->invalidate_range_end) { + if (!only_end && subscription->ops->invalidate_range) + subscription->ops->invalidate_range(subscription, + range->mm, + range->start, + range->end); + if (subscription->ops->invalidate_range_end) { if (!mmu_notifier_range_blockable(range)) non_block_start(); - mn->ops->invalidate_range_end(mn, range); + subscription->ops->invalidate_range_end(subscription, + range); if (!mmu_notifier_range_blockable(range)) non_block_end(); } @@ -556,13 +569,15 @@ void __mmu_notifier_invalidate_range_end(struct mmu_notifier_range *range, void __mmu_notifier_invalidate_range(struct mm_struct *mm, unsigned long start, unsigned long end) { - struct mmu_notifier *mn; + struct mmu_notifier *subscription; int id; id = srcu_read_lock(&srcu); - hlist_for_each_entry_rcu(mn, &mm->notifier_subscriptions->list, hlist) { - if (mn->ops->invalidate_range) - mn->ops->invalidate_range(mn, mm, start, end); + hlist_for_each_entry_rcu(subscription, + &mm->notifier_subscriptions->list, hlist) { + if (subscription->ops->invalidate_range) + subscription->ops->invalidate_range(subscription, mm, + start, end); } srcu_read_unlock(&srcu, id); } @@ -572,7 +587,8 @@ void __mmu_notifier_invalidate_range(struct mm_struct *mm, * write mode. A NULL mn signals the notifier is being registered for itree * mode. */ -int __mmu_notifier_register(struct mmu_notifier *mn, struct mm_struct *mm) +int __mmu_notifier_register(struct mmu_notifier *subscription, + struct mm_struct *mm) { struct mmu_notifier_subscriptions *subscriptions = NULL; int ret; @@ -629,14 +645,14 @@ int __mmu_notifier_register(struct mmu_notifier *mn, struct mm_struct *mm) if (subscriptions) smp_store_release(&mm->notifier_subscriptions, subscriptions); - if (mn) { + if (subscription) { /* Pairs with the mmdrop in mmu_notifier_unregister_* */ mmgrab(mm); - mn->mm = mm; - mn->users = 1; + subscription->mm = mm; + subscription->users = 1; spin_lock(&mm->notifier_subscriptions->lock); - hlist_add_head_rcu(&mn->hlist, + hlist_add_head_rcu(&subscription->hlist, &mm->notifier_subscriptions->list); spin_unlock(&mm->notifier_subscriptions->lock); } else @@ -668,15 +684,16 @@ EXPORT_SYMBOL_GPL(__mmu_notifier_register); * mmu_notifier_unregister() or mmu_notifier_put() must be always called to * unregister the notifier. * - * While the caller has a mmu_notifier get the mn->mm pointer will remain + * While the caller has a mmu_notifier get the subscription->mm pointer will remain * valid, and can be converted to an active mm pointer via mmget_not_zero(). */ -int mmu_notifier_register(struct mmu_notifier *mn, struct mm_struct *mm) +int mmu_notifier_register(struct mmu_notifier *subscription, + struct mm_struct *mm) { int ret; down_write(&mm->mmap_sem); - ret = __mmu_notifier_register(mn, mm); + ret = __mmu_notifier_register(subscription, mm); up_write(&mm->mmap_sem); return ret; } @@ -685,20 +702,20 @@ EXPORT_SYMBOL_GPL(mmu_notifier_register); static struct mmu_notifier * find_get_mmu_notifier(struct mm_struct *mm, const struct mmu_notifier_ops *ops) { - struct mmu_notifier *mn; + struct mmu_notifier *subscription; spin_lock(&mm->notifier_subscriptions->lock); - hlist_for_each_entry_rcu(mn, &mm->notifier_subscriptions->list, - hlist) { - if (mn->ops != ops) + hlist_for_each_entry_rcu(subscription, + &mm->notifier_subscriptions->list, hlist) { + if (subscription->ops != ops) continue; - if (likely(mn->users != UINT_MAX)) - mn->users++; + if (likely(subscription->users != UINT_MAX)) + subscription->users++; else - mn = ERR_PTR(-EOVERFLOW); + subscription = ERR_PTR(-EOVERFLOW); spin_unlock(&mm->notifier_subscriptions->lock); - return mn; + return subscription; } spin_unlock(&mm->notifier_subscriptions->lock); return NULL; @@ -724,27 +741,27 @@ find_get_mmu_notifier(struct mm_struct *mm, const struct mmu_notifier_ops *ops) struct mmu_notifier *mmu_notifier_get_locked(const struct mmu_notifier_ops *ops, struct mm_struct *mm) { - struct mmu_notifier *mn; + struct mmu_notifier *subscription; int ret; lockdep_assert_held_write(&mm->mmap_sem); if (mm->notifier_subscriptions) { - mn = find_get_mmu_notifier(mm, ops); - if (mn) - return mn; + subscription = find_get_mmu_notifier(mm, ops); + if (subscription) + return subscription; } - mn = ops->alloc_notifier(mm); - if (IS_ERR(mn)) - return mn; - mn->ops = ops; - ret = __mmu_notifier_register(mn, mm); + subscription = ops->alloc_notifier(mm); + if (IS_ERR(subscription)) + return subscription; + subscription->ops = ops; + ret = __mmu_notifier_register(subscription, mm); if (ret) goto out_free; - return mn; + return subscription; out_free: - mn->ops->free_notifier(mn); + subscription->ops->free_notifier(subscription); return ERR_PTR(ret); } EXPORT_SYMBOL_GPL(mmu_notifier_get_locked); @@ -767,11 +784,12 @@ void __mmu_notifier_subscriptions_destroy(struct mm_struct *mm) * and only after mmu_notifier_unregister returned we're guaranteed * that ->release or any other method can't run anymore. */ -void mmu_notifier_unregister(struct mmu_notifier *mn, struct mm_struct *mm) +void mmu_notifier_unregister(struct mmu_notifier *subscription, + struct mm_struct *mm) { BUG_ON(atomic_read(&mm->mm_count) <= 0); - if (!hlist_unhashed(&mn->hlist)) { + if (!hlist_unhashed(&subscription->hlist)) { /* * SRCU here will force exit_mmap to wait for ->release to * finish before freeing the pages. @@ -783,8 +801,8 @@ void mmu_notifier_unregister(struct mmu_notifier *mn, struct mm_struct *mm) * exit_mmap will block in mmu_notifier_release to guarantee * that ->release is called before freeing the pages. */ - if (mn->ops->release) - mn->ops->release(mn, mm); + if (subscription->ops->release) + subscription->ops->release(subscription, mm); srcu_read_unlock(&srcu, id); spin_lock(&mm->notifier_subscriptions->lock); @@ -792,7 +810,7 @@ void mmu_notifier_unregister(struct mmu_notifier *mn, struct mm_struct *mm) * Can not use list_del_rcu() since __mmu_notifier_release * can delete it before we hold the lock. */ - hlist_del_init_rcu(&mn->hlist); + hlist_del_init_rcu(&subscription->hlist); spin_unlock(&mm->notifier_subscriptions->lock); } @@ -810,10 +828,11 @@ EXPORT_SYMBOL_GPL(mmu_notifier_unregister); static void mmu_notifier_free_rcu(struct rcu_head *rcu) { - struct mmu_notifier *mn = container_of(rcu, struct mmu_notifier, rcu); - struct mm_struct *mm = mn->mm; + struct mmu_notifier *subscription = + container_of(rcu, struct mmu_notifier, rcu); + struct mm_struct *mm = subscription->mm; - mn->ops->free_notifier(mn); + subscription->ops->free_notifier(subscription); /* Pairs with the get in __mmu_notifier_register() */ mmdrop(mm); } @@ -840,17 +859,17 @@ static void mmu_notifier_free_rcu(struct rcu_head *rcu) * Modules calling this function must call mmu_notifier_synchronize() in * their __exit functions to ensure the async work is completed. */ -void mmu_notifier_put(struct mmu_notifier *mn) +void mmu_notifier_put(struct mmu_notifier *subscription) { - struct mm_struct *mm = mn->mm; + struct mm_struct *mm = subscription->mm; spin_lock(&mm->notifier_subscriptions->lock); - if (WARN_ON(!mn->users) || --mn->users) + if (WARN_ON(!subscription->users) || --subscription->users) goto out_unlock; - hlist_del_init_rcu(&mn->hlist); + hlist_del_init_rcu(&subscription->hlist); spin_unlock(&mm->notifier_subscriptions->lock); - call_srcu(&srcu, &mn->rcu, mmu_notifier_free_rcu); + call_srcu(&srcu, &subscription->rcu, mmu_notifier_free_rcu); return; out_unlock: