Commit da1c55f1 authored by Michel Lespinasse's avatar Michel Lespinasse Committed by Linus Torvalds

mmap locking API: rename mmap_sem to mmap_lock

Rename the mmap_sem field to mmap_lock.  Any new uses of this lock should
now go through the new mmap locking api.  The mmap_lock is still
implemented as a rwsem, though this could change in the future.

[akpm@linux-foundation.org: fix it for mm-gup-might_lock_readmmap_sem-in-get_user_pages_fast.patch]
Signed-off-by: default avatarMichel Lespinasse <walken@google.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Reviewed-by: default avatarVlastimil Babka <vbabka@suse.cz>
Reviewed-by: default avatarDavidlohr Bueso <dbueso@suse.de>
Reviewed-by: default avatarDaniel Jordan <daniel.m.jordan@oracle.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Laurent Dufour <ldufour@linux.ibm.com>
Cc: Liam Howlett <Liam.Howlett@oracle.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ying Han <yinghan@google.com>
Link: http://lkml.kernel.org/r/20200520052908.204642-11-walken@google.comSigned-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 42fc5414
......@@ -74,8 +74,8 @@ ia64_do_page_fault (unsigned long address, unsigned long isr, struct pt_regs *re
mask = ((((isr >> IA64_ISR_X_BIT) & 1UL) << VM_EXEC_BIT)
| (((isr >> IA64_ISR_W_BIT) & 1UL) << VM_WRITE_BIT));
/* mmap_sem is performance critical.... */
prefetchw(&mm->mmap_sem);
/* mmap_lock is performance critical.... */
prefetchw(&mm->mmap_lock);
/*
* If we're in an interrupt or have no user context, we must not take the fault..
......
......@@ -1359,7 +1359,7 @@ dotraplinkage void
do_page_fault(struct pt_regs *regs, unsigned long hw_error_code,
unsigned long address)
{
prefetchw(&current->mm->mmap_sem);
prefetchw(&current->mm->mmap_lock);
/*
* KVM has two types of events that are, logically, interrupts, but
* are unfortunately delivered using the #PF vector. These events are
......
......@@ -661,7 +661,7 @@ static int etnaviv_gem_userptr_get_pages(struct etnaviv_gem_object *etnaviv_obj)
struct etnaviv_gem_userptr *userptr = &etnaviv_obj->userptr;
int ret, pinned = 0, npages = etnaviv_obj->base.size >> PAGE_SHIFT;
might_lock_read(&current->mm->mmap_sem);
might_lock_read(&current->mm->mmap_lock);
if (userptr->mm != current->mm)
return -EPERM;
......
......@@ -440,7 +440,7 @@ struct mm_struct {
spinlock_t page_table_lock; /* Protects page tables and some
* counters
*/
struct rw_semaphore mmap_sem;
struct rw_semaphore mmap_lock;
struct list_head mmlist; /* List of maybe swapped mm's. These
* are globally strung together off
......
......@@ -4,67 +4,67 @@
#include <linux/mmdebug.h>
#define MMAP_LOCK_INITIALIZER(name) \
.mmap_sem = __RWSEM_INITIALIZER((name).mmap_sem),
.mmap_lock = __RWSEM_INITIALIZER((name).mmap_lock),
static inline void mmap_init_lock(struct mm_struct *mm)
{
init_rwsem(&mm->mmap_sem);
init_rwsem(&mm->mmap_lock);
}
static inline void mmap_write_lock(struct mm_struct *mm)
{
down_write(&mm->mmap_sem);
down_write(&mm->mmap_lock);
}
static inline void mmap_write_lock_nested(struct mm_struct *mm, int subclass)
{
down_write_nested(&mm->mmap_sem, subclass);
down_write_nested(&mm->mmap_lock, subclass);
}
static inline int mmap_write_lock_killable(struct mm_struct *mm)
{
return down_write_killable(&mm->mmap_sem);
return down_write_killable(&mm->mmap_lock);
}
static inline bool mmap_write_trylock(struct mm_struct *mm)
{
return down_write_trylock(&mm->mmap_sem) != 0;
return down_write_trylock(&mm->mmap_lock) != 0;
}
static inline void mmap_write_unlock(struct mm_struct *mm)
{
up_write(&mm->mmap_sem);
up_write(&mm->mmap_lock);
}
static inline void mmap_write_downgrade(struct mm_struct *mm)
{
downgrade_write(&mm->mmap_sem);
downgrade_write(&mm->mmap_lock);
}
static inline void mmap_read_lock(struct mm_struct *mm)
{
down_read(&mm->mmap_sem);
down_read(&mm->mmap_lock);
}
static inline int mmap_read_lock_killable(struct mm_struct *mm)
{
return down_read_killable(&mm->mmap_sem);
return down_read_killable(&mm->mmap_lock);
}
static inline bool mmap_read_trylock(struct mm_struct *mm)
{
return down_read_trylock(&mm->mmap_sem) != 0;
return down_read_trylock(&mm->mmap_lock) != 0;
}
static inline void mmap_read_unlock(struct mm_struct *mm)
{
up_read(&mm->mmap_sem);
up_read(&mm->mmap_lock);
}
static inline bool mmap_read_trylock_non_owner(struct mm_struct *mm)
{
if (down_read_trylock(&mm->mmap_sem)) {
rwsem_release(&mm->mmap_sem.dep_map, _RET_IP_);
if (down_read_trylock(&mm->mmap_lock)) {
rwsem_release(&mm->mmap_lock.dep_map, _RET_IP_);
return true;
}
return false;
......@@ -72,19 +72,19 @@ static inline bool mmap_read_trylock_non_owner(struct mm_struct *mm)
static inline void mmap_read_unlock_non_owner(struct mm_struct *mm)
{
up_read_non_owner(&mm->mmap_sem);
up_read_non_owner(&mm->mmap_lock);
}
static inline void mmap_assert_locked(struct mm_struct *mm)
{
lockdep_assert_held(&mm->mmap_sem);
VM_BUG_ON_MM(!rwsem_is_locked(&mm->mmap_sem), mm);
lockdep_assert_held(&mm->mmap_lock);
VM_BUG_ON_MM(!rwsem_is_locked(&mm->mmap_lock), mm);
}
static inline void mmap_assert_write_locked(struct mm_struct *mm)
{
lockdep_assert_held_write(&mm->mmap_sem);
VM_BUG_ON_MM(!rwsem_is_locked(&mm->mmap_sem), mm);
lockdep_assert_held_write(&mm->mmap_lock);
VM_BUG_ON_MM(!rwsem_is_locked(&mm->mmap_lock), mm);
}
#endif /* _LINUX_MMAP_LOCK_H */
......@@ -2750,7 +2750,7 @@ static int internal_get_user_pages_fast(unsigned long start, int nr_pages,
return -EINVAL;
if (!(gup_flags & FOLL_FAST_ONLY))
might_lock_read(&current->mm->mmap_sem);
might_lock_read(&current->mm->mmap_lock);
start = untagged_addr(start) & PAGE_MASK;
addr = start;
......
......@@ -4804,7 +4804,7 @@ void __might_fault(const char *file, int line)
__might_sleep(file, line, 0);
#if defined(CONFIG_DEBUG_ATOMIC_SLEEP)
if (current->mm)
might_lock_read(&current->mm->mmap_sem);
might_lock_read(&current->mm->mmap_lock);
#endif
}
EXPORT_SYMBOL(__might_fault);
......
......@@ -3474,7 +3474,7 @@ static void vm_lock_anon_vma(struct mm_struct *mm, struct anon_vma *anon_vma)
* The LSB of head.next can't change from under us
* because we hold the mm_all_locks_mutex.
*/
down_write_nest_lock(&anon_vma->root->rwsem, &mm->mmap_sem);
down_write_nest_lock(&anon_vma->root->rwsem, &mm->mmap_lock);
/*
* We can safely modify head.next after taking the
* anon_vma->root->rwsem. If some other vma in this mm shares
......@@ -3504,7 +3504,7 @@ static void vm_lock_mapping(struct mm_struct *mm, struct address_space *mapping)
*/
if (test_and_set_bit(AS_MM_ALL_LOCKS, &mapping->flags))
BUG();
down_write_nest_lock(&mapping->i_mmap_rwsem, &mm->mmap_sem);
down_write_nest_lock(&mapping->i_mmap_rwsem, &mm->mmap_lock);
}
}
......
......@@ -983,7 +983,7 @@ int mmu_interval_notifier_insert(struct mmu_interval_notifier *interval_sub,
struct mmu_notifier_subscriptions *subscriptions;
int ret;
might_lock(&mm->mmap_sem);
might_lock(&mm->mmap_lock);
subscriptions = smp_load_acquire(&mm->notifier_subscriptions);
if (!subscriptions || !subscriptions->has_itree) {
......
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