[PATCH 91/94] mm: Remove vma linked list.
From: Liam Howlett
Date: Wed Apr 28 2021 - 11:44:25 EST
The vma linked list has been replaced by the maple tree iterators and
vma_next() vma_prev() functions.
A part of this change is also the iterators free_pgd_range(),
zap_page_range(), and unmap_single_vma()
The internal _vma_next() has been dropped.
Signed-off-by: Liam R. Howlett <Liam.Howlett@xxxxxxxxxx>
---
fs/proc/task_nommu.c | 2 +-
include/linux/mm.h | 2 +-
include/linux/mm_types.h | 6 -
kernel/fork.c | 15 +-
mm/debug.c | 12 +-
mm/internal.h | 4 +-
mm/memory.c | 41 ++-
mm/mmap.c | 573 +++++++++++++++++----------------------
mm/nommu.c | 14 +-
9 files changed, 301 insertions(+), 368 deletions(-)
diff --git a/fs/proc/task_nommu.c b/fs/proc/task_nommu.c
index 8691a1216d1c..be02e8997ddf 100644
--- a/fs/proc/task_nommu.c
+++ b/fs/proc/task_nommu.c
@@ -246,7 +246,7 @@ static void *m_next(struct seq_file *m, void *_p, loff_t *pos)
struct vm_area_struct *vma = _p;
*pos = vma->vm_end;
- return vma->vm_next;
+ return vma_next(vma->vm_mm, vma);
}
static const struct seq_operations proc_pid_maps_ops = {
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 82b076787515..e1f1ae32fa9d 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -1731,7 +1731,7 @@ void zap_vma_ptes(struct vm_area_struct *vma, unsigned long address,
void zap_page_range(struct vm_area_struct *vma, unsigned long address,
unsigned long size);
void unmap_vmas(struct mmu_gather *tlb, struct vm_area_struct *start_vma,
- unsigned long start, unsigned long end);
+ struct ma_state *mas, unsigned long start, unsigned long end);
struct mmu_notifier_range;
diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
index 304692ada024..ca9fb13c2aca 100644
--- a/include/linux/mm_types.h
+++ b/include/linux/mm_types.h
@@ -303,14 +303,11 @@ struct vm_userfaultfd_ctx {};
* library, the executable area etc).
*/
struct vm_area_struct {
- /* The first cache line has the info for VMA tree walking. */
-
unsigned long vm_start; /* Our start address within vm_mm. */
unsigned long vm_end; /* The first byte after our end address
within vm_mm. */
/* linked list of VM areas per task, sorted by address */
- struct vm_area_struct *vm_next, *vm_prev;
struct mm_struct *vm_mm; /* The address space we belong to. */
/*
@@ -324,7 +321,6 @@ struct vm_area_struct {
unsigned long vm_pgoff; /* Offset (within vm_file) in PAGE_SIZE
* units
*/
- /* Second cache line starts here. */
struct file *vm_file; /* File we map to (can be NULL). */
/*
* For areas with an address space and backing store,
@@ -378,7 +374,6 @@ struct core_state {
struct kioctx_table;
struct mm_struct {
struct {
- struct vm_area_struct *mmap; /* list of VMAs */
struct maple_tree mm_mt;
#ifdef CONFIG_MMU
unsigned long (*get_unmapped_area) (struct file *filp,
@@ -393,7 +388,6 @@ struct mm_struct {
unsigned long mmap_compat_legacy_base;
#endif
unsigned long task_size; /* size of task vm space */
- unsigned long highest_vm_end; /* highest vma end address */
pgd_t * pgd;
#ifdef CONFIG_MEMBARRIER
diff --git a/kernel/fork.c b/kernel/fork.c
index fe0922f75cc5..6da1022e8758 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -364,7 +364,6 @@ struct vm_area_struct *vm_area_dup(struct vm_area_struct *orig)
*/
*new = data_race(*orig);
INIT_LIST_HEAD(&new->anon_vma_chain);
- new->vm_next = new->vm_prev = NULL;
}
return new;
}
@@ -473,7 +472,7 @@ EXPORT_SYMBOL(free_task);
static __latent_entropy int dup_mmap(struct mm_struct *mm,
struct mm_struct *oldmm)
{
- struct vm_area_struct *mpnt, *tmp, *prev, **pprev;
+ struct vm_area_struct *mpnt, *tmp;
int retval;
unsigned long charge = 0;
MA_STATE(old_mas, &oldmm->mm_mt, 0, 0);
@@ -500,7 +499,6 @@ static __latent_entropy int dup_mmap(struct mm_struct *mm,
mm->exec_vm = oldmm->exec_vm;
mm->stack_vm = oldmm->stack_vm;
- pprev = &mm->mmap;
retval = ksm_fork(mm, oldmm);
if (retval)
goto out;
@@ -508,8 +506,6 @@ static __latent_entropy int dup_mmap(struct mm_struct *mm,
if (retval)
goto out;
- prev = NULL;
-
retval = mas_entry_count(&mas, oldmm->map_count);
if (retval)
goto fail_nomem;
@@ -585,14 +581,6 @@ static __latent_entropy int dup_mmap(struct mm_struct *mm,
if (is_vm_hugetlb_page(tmp))
reset_vma_resv_huge_pages(tmp);
- /*
- * Link in the new vma and copy the page table entries.
- */
- *pprev = tmp;
- pprev = &tmp->vm_next;
- tmp->vm_prev = prev;
- prev = tmp;
-
/* Link the vma into the MT */
mas.index = tmp->vm_start;
mas.last = tmp->vm_end - 1;
@@ -1024,7 +1012,6 @@ static void mm_init_uprobes_state(struct mm_struct *mm)
static struct mm_struct *mm_init(struct mm_struct *mm, struct task_struct *p,
struct user_namespace *user_ns)
{
- mm->mmap = NULL;
mt_init_flags(&mm->mm_mt, MAPLE_ALLOC_RANGE);
atomic_set(&mm->mm_users, 1);
atomic_set(&mm->mm_count, 1);
diff --git a/mm/debug.c b/mm/debug.c
index f382d319722a..55afc85c4fcc 100644
--- a/mm/debug.c
+++ b/mm/debug.c
@@ -203,8 +203,8 @@ void dump_vma(const struct vm_area_struct *vma)
"prot %lx anon_vma %px vm_ops %px\n"
"pgoff %lx file %px private_data %px\n"
"flags: %#lx(%pGv)\n",
- vma, (void *)vma->vm_start, (void *)vma->vm_end, vma->vm_next,
- vma->vm_prev, vma->vm_mm,
+ vma, (void *)vma->vm_start, (void *)vma->vm_end,
+ vma_next(vma->vm_mm, vma), vma_prev(vma->vm_mm, vma), vma->vm_mm,
(unsigned long)pgprot_val(vma->vm_page_prot),
vma->anon_vma, vma->vm_ops, vma->vm_pgoff,
vma->vm_file, vma->vm_private_data,
@@ -214,11 +214,11 @@ EXPORT_SYMBOL(dump_vma);
void dump_mm(const struct mm_struct *mm)
{
- pr_emerg("mm %px mmap %px task_size %lu\n"
+ pr_emerg("mm %px task_size %lu\n"
#ifdef CONFIG_MMU
"get_unmapped_area %px\n"
#endif
- "mmap_base %lu mmap_legacy_base %lu highest_vm_end %lu\n"
+ "mmap_base %lu mmap_legacy_base %lu\n"
"pgd %px mm_users %d mm_count %d pgtables_bytes %lu map_count %d\n"
"hiwater_rss %lx hiwater_vm %lx total_vm %lx locked_vm %lx\n"
"pinned_vm %llx data_vm %lx exec_vm %lx stack_vm %lx\n"
@@ -242,11 +242,11 @@ void dump_mm(const struct mm_struct *mm)
"tlb_flush_pending %d\n"
"def_flags: %#lx(%pGv)\n",
- mm, mm->mmap, mm->task_size,
+ mm, mm->task_size,
#ifdef CONFIG_MMU
mm->get_unmapped_area,
#endif
- mm->mmap_base, mm->mmap_legacy_base, mm->highest_vm_end,
+ mm->mmap_base, mm->mmap_legacy_base,
mm->pgd, atomic_read(&mm->mm_users),
atomic_read(&mm->mm_count),
mm_pgtables_bytes(mm),
diff --git a/mm/internal.h b/mm/internal.h
index 34d00548aa81..0fb161ee7f73 100644
--- a/mm/internal.h
+++ b/mm/internal.h
@@ -36,8 +36,8 @@ void page_writeback_init(void);
vm_fault_t do_swap_page(struct vm_fault *vmf);
-void free_pgtables(struct mmu_gather *tlb, struct vm_area_struct *start_vma,
- unsigned long floor, unsigned long ceiling);
+void free_pgtables(struct mmu_gather *tlb, struct ma_state *mas,
+ struct vm_area_struct *vma, unsigned long floor, unsigned long ceiling);
static inline bool can_madv_lru_vma(struct vm_area_struct *vma)
{
diff --git a/mm/memory.c b/mm/memory.c
index 91e2a4c8dfd3..4de079ad0d48 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -399,13 +399,18 @@ void free_pgd_range(struct mmu_gather *tlb,
} while (pgd++, addr = next, addr != end);
}
-void free_pgtables(struct mmu_gather *tlb, struct vm_area_struct *vma,
- unsigned long floor, unsigned long ceiling)
+void free_pgtables(struct mmu_gather *tlb, struct ma_state *mas,
+ struct vm_area_struct *vma, unsigned long floor, unsigned long ceiling)
{
- while (vma) {
- struct vm_area_struct *next = vma->vm_next;
+ struct vm_area_struct *next;
+ struct ma_state ma_next = *mas;
+
+ do {
unsigned long addr = vma->vm_start;
+ next = mas_find(&ma_next, ceiling - 1);
+ BUG_ON(vma->vm_start < floor);
+ BUG_ON(vma->vm_end - 1 > ceiling - 1);
/*
* Hide vma from rmap and truncate_pagecache before freeing
* pgtables
@@ -422,16 +427,20 @@ void free_pgtables(struct mmu_gather *tlb, struct vm_area_struct *vma,
*/
while (next && next->vm_start <= vma->vm_end + PMD_SIZE
&& !is_vm_hugetlb_page(next)) {
+ *mas = ma_next;
vma = next;
- next = vma->vm_next;
+ next = mas_find(&ma_next, ceiling - 1);
+ BUG_ON(vma->vm_start < floor);
+ BUG_ON(vma->vm_end -1 > ceiling - 1);
unlink_anon_vmas(vma);
unlink_file_vma(vma);
}
free_pgd_range(tlb, addr, vma->vm_end,
floor, next ? next->vm_start : ceiling);
}
+ *mas = ma_next;
vma = next;
- }
+ } while (vma);
}
int __pte_alloc(struct mm_struct *mm, pmd_t *pmd)
@@ -1510,16 +1519,19 @@ static void unmap_single_vma(struct mmu_gather *tlb,
* drops the lock and schedules.
*/
void unmap_vmas(struct mmu_gather *tlb,
- struct vm_area_struct *vma, unsigned long start_addr,
- unsigned long end_addr)
+ struct vm_area_struct *vma, struct ma_state *mas,
+ unsigned long start_addr, unsigned long end_addr)
{
struct mmu_notifier_range range;
mmu_notifier_range_init(&range, MMU_NOTIFY_UNMAP, 0, vma, vma->vm_mm,
start_addr, end_addr);
mmu_notifier_invalidate_range_start(&range);
- for ( ; vma && vma->vm_start < end_addr; vma = vma->vm_next)
+ do {
+ BUG_ON(vma->vm_start < start_addr);
+ BUG_ON(vma->vm_end > end_addr);
unmap_single_vma(tlb, vma, start_addr, end_addr, NULL);
+ } while ((vma = mas_find(mas, end_addr - 1)) != NULL);
mmu_notifier_invalidate_range_end(&range);
}
@@ -1536,15 +1548,20 @@ void zap_page_range(struct vm_area_struct *vma, unsigned long start,
{
struct mmu_notifier_range range;
struct mmu_gather tlb;
+ unsigned long end = start + size;
+ MA_STATE(mas, &vma->vm_mm->mm_mt, start, start);
lru_add_drain();
mmu_notifier_range_init(&range, MMU_NOTIFY_CLEAR, 0, vma, vma->vm_mm,
- start, start + size);
+ start, end);
tlb_gather_mmu(&tlb, vma->vm_mm);
update_hiwater_rss(vma->vm_mm);
mmu_notifier_invalidate_range_start(&range);
- for ( ; vma && vma->vm_start < range.end; vma = vma->vm_next)
- unmap_single_vma(&tlb, vma, start, range.end, NULL);
+ rcu_read_lock();
+ mas_for_each(&mas, vma, end - 1)
+ unmap_single_vma(&tlb, vma, start, end, NULL);
+ rcu_read_unlock();
+
mmu_notifier_invalidate_range_end(&range);
tlb_finish_mmu(&tlb);
}
diff --git a/mm/mmap.c b/mm/mmap.c
index ed1b9df86966..c2baf006bcde 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -74,10 +74,6 @@ int mmap_rnd_compat_bits __read_mostly = CONFIG_ARCH_MMAP_RND_COMPAT_BITS;
static bool ignore_rlimit_data;
core_param(ignore_rlimit_data, ignore_rlimit_data, bool, 0644);
-static void unmap_region(struct mm_struct *mm,
- struct vm_area_struct *vma, struct vm_area_struct *prev,
- unsigned long start, unsigned long end);
-
/* description of effects of mapping type and prot in current implementation.
* this is due to the limited x86 page protection hardware. The expected
* behavior is in parens:
@@ -175,10 +171,8 @@ void unlink_file_vma(struct vm_area_struct *vma)
/*
* Close a vm structure and free it, returning the next.
*/
-static struct vm_area_struct *remove_vma(struct vm_area_struct *vma)
+static void remove_vma(struct vm_area_struct *vma)
{
- struct vm_area_struct *next = vma->vm_next;
-
might_sleep();
if (vma->vm_ops && vma->vm_ops->close)
vma->vm_ops->close(vma);
@@ -186,13 +180,13 @@ static struct vm_area_struct *remove_vma(struct vm_area_struct *vma)
fput(vma->vm_file);
mpol_put(vma_policy(vma));
vm_area_free(vma);
- return next;
}
static int do_brk_munmap(struct ma_state *mas, struct vm_area_struct *vma,
unsigned long newbrk, unsigned long oldbrk,
struct list_head *uf);
-static int do_brk_flags(struct ma_state *mas, struct vm_area_struct **brkvma,
+static int do_brk_flags(struct ma_state *mas, struct ma_state *ma_prev,
+ struct vm_area_struct **brkvma,
unsigned long addr, unsigned long request,
unsigned long flags);
SYSCALL_DEFINE1(brk, unsigned long, brk)
@@ -205,6 +199,7 @@ SYSCALL_DEFINE1(brk, unsigned long, brk)
bool downgraded = false;
LIST_HEAD(uf);
MA_STATE(mas, &mm->mm_mt, 0, 0);
+ struct ma_state ma_neighbour;
if (mmap_write_lock_killable(mm))
return -EINTR;
@@ -261,7 +256,6 @@ SYSCALL_DEFINE1(brk, unsigned long, brk)
* before calling do_brk_munmap().
*/
mm->brk = brk;
- mas.last = oldbrk - 1;
ret = do_brk_munmap(&mas, brkvma, newbrk, oldbrk, &uf);
if (ret == 1) {
downgraded = true;
@@ -272,26 +266,26 @@ SYSCALL_DEFINE1(brk, unsigned long, brk)
mm->brk = origbrk;
goto out;
}
+ ma_neighbour = mas;
+ next = mas_next(&ma_neighbour, newbrk + PAGE_SIZE + stack_guard_gap);
/* Only check if the next VMA is within the stack_guard_gap of the
* expansion area */
- next = mas_next(&mas, newbrk + PAGE_SIZE + stack_guard_gap);
/* Check against existing mmap mappings. */
if (next && newbrk + PAGE_SIZE > vm_start_gap(next))
goto out;
- brkvma = mas_prev(&mas, mm->start_brk);
+ brkvma = mas_prev(&ma_neighbour, mm->start_brk);
if (brkvma) {
- if(brkvma->vm_start >= oldbrk)
+ if (brkvma->vm_start >= oldbrk)
goto out; // Trying to map over another vma.
- if (brkvma->vm_end <= min_brk) {
+ if (brkvma->vm_end <= min_brk)
brkvma = NULL;
- mas_reset(&mas);
- }
}
/* Ok, looks good - let it rip. */
- if (do_brk_flags(&mas, &brkvma, oldbrk, newbrk - oldbrk, 0) < 0)
+ if (do_brk_flags(&mas, &ma_neighbour, &brkvma, oldbrk,
+ newbrk - oldbrk, 0) < 0)
goto out;
mm->brk = brk;
@@ -316,85 +310,17 @@ SYSCALL_DEFINE1(brk, unsigned long, brk)
extern void mt_validate(struct maple_tree *mt);
extern void mt_dump(const struct maple_tree *mt);
-/* Validate the maple tree */
-static void validate_mm_mt(struct mm_struct *mm)
-{
- struct maple_tree *mt = &mm->mm_mt;
- struct vm_area_struct *vma_mt, *vma = mm->mmap;
-
- MA_STATE(mas, mt, 0, 0);
- rcu_read_lock();
- mas_for_each(&mas, vma_mt, ULONG_MAX) {
- if (xa_is_zero(vma_mt))
- continue;
-
- if (!vma)
- break;
-
- if ((vma != vma_mt) ||
- (vma->vm_start != vma_mt->vm_start) ||
- (vma->vm_end != vma_mt->vm_end) ||
- (vma->vm_start != mas.index) ||
- (vma->vm_end - 1 != mas.last)) {
- pr_emerg("issue in %s\n", current->comm);
- dump_stack();
-#ifdef CONFIG_DEBUG_VM
- dump_vma(vma_mt);
- pr_emerg("and vm_next\n");
- dump_vma(vma->vm_next);
-#endif // CONFIG_DEBUG_VM
- pr_emerg("mt piv: %px %lu - %lu\n", vma_mt,
- mas.index, mas.last);
- pr_emerg("mt vma: %px %lu - %lu\n", vma_mt,
- vma_mt->vm_start, vma_mt->vm_end);
- if (vma->vm_prev) {
- pr_emerg("ll prev: %px %lu - %lu\n",
- vma->vm_prev, vma->vm_prev->vm_start,
- vma->vm_prev->vm_end);
- }
- pr_emerg("ll vma: %px %lu - %lu\n", vma,
- vma->vm_start, vma->vm_end);
- if (vma->vm_next) {
- pr_emerg("ll next: %px %lu - %lu\n",
- vma->vm_next, vma->vm_next->vm_start,
- vma->vm_next->vm_end);
- }
-
- mt_dump(mas.tree);
- if (vma_mt->vm_end != mas.last + 1) {
- pr_err("vma: %px vma_mt %lu-%lu\tmt %lu-%lu\n",
- mm, vma_mt->vm_start, vma_mt->vm_end,
- mas.index, mas.last);
- mt_dump(mas.tree);
- }
- VM_BUG_ON_MM(vma_mt->vm_end != mas.last + 1, mm);
- if (vma_mt->vm_start != mas.index) {
- pr_err("vma: %px vma_mt %px %lu - %lu doesn't match\n",
- mm, vma_mt, vma_mt->vm_start, vma_mt->vm_end);
- mt_dump(mas.tree);
- }
- VM_BUG_ON_MM(vma_mt->vm_start != mas.index, mm);
- }
- VM_BUG_ON(vma != vma_mt);
- vma = vma->vm_next;
-
- }
- VM_BUG_ON(vma);
-
- rcu_read_unlock();
- mt_validate(&mm->mm_mt);
-}
-
static void validate_mm(struct mm_struct *mm)
{
int bug = 0;
int i = 0;
- unsigned long highest_address = 0;
- struct vm_area_struct *vma = mm->mmap;
+ struct vm_area_struct *vma;
+ MA_STATE(mas, &mm->mm_mt, 0, 0);
- validate_mm_mt(mm);
+ mmap_assert_locked(mm);
- while (vma) {
+ mt_validate(&mm->mm_mt);
+ mas_for_each(&mas, vma, ULONG_MAX) {
#ifdef CONFIG_DEBUG_VM_RB
struct anon_vma *anon_vma = vma->anon_vma;
struct anon_vma_chain *avc;
@@ -405,24 +331,18 @@ static void validate_mm(struct mm_struct *mm)
anon_vma_unlock_read(anon_vma);
}
#endif
- highest_address = vm_end_gap(vma);
- vma = vma->vm_next;
+ VM_BUG_ON(mas.index != vma->vm_start);
+ VM_BUG_ON(mas.last != vma->vm_end - 1);
i++;
}
if (i != mm->map_count) {
- pr_emerg("map_count %d vm_next %d\n", mm->map_count, i);
- bug = 1;
- }
- if (highest_address != mm->highest_vm_end) {
- pr_emerg("mm->highest_vm_end %lx, found %lx\n",
- mm->highest_vm_end, highest_address);
+ pr_emerg("map_count %d mas_for_each %d\n", mm->map_count, i);
bug = 1;
}
VM_BUG_ON_MM(bug, mm);
}
#else // !CONFIG_DEBUG_MAPLE_TREE
-#define validate_mm_mt(root) do { } while (0)
#define validate_mm(mm) do { } while (0)
#endif // CONFIG_DEBUG_MAPLE_TREE
@@ -469,7 +389,7 @@ anon_vma_interval_tree_post_update_vma(struct vm_area_struct *vma)
*
* Returns: True if there is an overlapping VMA, false otherwise
*/
-static bool range_has_overlap(struct mm_struct *mm, unsigned long start,
+static inline bool range_has_overlap(struct mm_struct *mm, unsigned long start,
unsigned long end, struct vm_area_struct **pprev)
{
struct vm_area_struct *existing;
@@ -480,24 +400,6 @@ static bool range_has_overlap(struct mm_struct *mm, unsigned long start,
return existing ? true : false;
}
-/*
- * _vma_next() - Get the next VMA or the first.
- * @mm: The mm_struct.
- * @vma: The current vma.
- *
- * If @vma is NULL, return the first vma in the mm.
- *
- * Returns: The next VMA after @vma.
- */
-static inline struct vm_area_struct *_vma_next(struct mm_struct *mm,
- struct vm_area_struct *vma)
-{
- if (!vma)
- return mm->mmap;
-
- return vma->vm_next;
-}
-
static unsigned long count_vma_pages_range(struct mm_struct *mm,
unsigned long addr, unsigned long end)
{
@@ -573,7 +475,7 @@ static inline void vma_mt_store(struct mm_struct *mm, struct vm_area_struct *vma
}
static void vma_mas_link(struct mm_struct *mm, struct vm_area_struct *vma,
- struct ma_state *mas, struct vm_area_struct *prev)
+ struct ma_state *mas)
{
struct address_space *mapping = NULL;
@@ -592,36 +494,26 @@ static void vma_mas_link(struct mm_struct *mm, struct vm_area_struct *vma,
validate_mm(mm);
}
-static void vma_link(struct mm_struct *mm, struct vm_area_struct *vma,
- struct vm_area_struct *prev)
+static void vma_link(struct mm_struct *mm, struct vm_area_struct *vma)
{
- struct address_space *mapping = NULL;
-
- if (vma->vm_file) {
- mapping = vma->vm_file->f_mapping;
- i_mmap_lock_write(mapping);
- }
-
- vma_mt_store(mm, vma);
- __vma_link_file(vma);
+ MA_STATE(mas, &mm->mm_mt, vma->vm_start, vma->vm_end - 1);
- if (mapping)
- i_mmap_unlock_write(mapping);
-
- mm->map_count++;
- validate_mm(mm);
+ vma_mas_link(mm, vma, &mas);
}
/*
* Helper for vma_adjust() in the split_vma insert case: insert a vma into the
* mm's list and the mm tree. It has already been inserted into the interval tree.
*/
-static void __insert_vm_struct(struct mm_struct *mm, struct vm_area_struct *vma)
+static inline void __insert_vm_struct(struct mm_struct *mm,
+ struct vm_area_struct *vma)
{
- struct vm_area_struct *prev;
+ MA_STATE(mas, &mm->mm_mt, vma->vm_start, vma->vm_end - 1);
+
+ BUG_ON(mas_find(&mas, vma->vm_end - 1));
+ mas_reset(&mas);
- BUG_ON(range_has_overlap(mm, vma->vm_start, vma->vm_end, &prev));
- vma_mt_store(mm, vma);
+ vma_mas_store(vma, &mas);
mm->map_count++;
}
@@ -637,9 +529,11 @@ inline int vma_expand(struct ma_state *mas, struct vm_area_struct *vma,
bool remove_next = false;
int error;
+
if (next && (vma != next) && (end == next->vm_end)) {
+ /* Expanding existing VMA over a gap and next */
remove_next = true;
- if (next->anon_vma && !vma->anon_vma) {
+ if (next->anon_vma && !anon_vma) {
vma->anon_vma = next->anon_vma;
error = anon_vma_clone(vma, next);
if (error)
@@ -669,7 +563,6 @@ inline int vma_expand(struct ma_state *mas, struct vm_area_struct *vma,
vma->vm_start = start;
vma->vm_end = end;
vma->vm_pgoff = pgoff;
- /* Note: mas must be pointing to the expanding VMA */
vma_mas_store(vma, mas);
if (file) {
@@ -678,11 +571,8 @@ inline int vma_expand(struct ma_state *mas, struct vm_area_struct *vma,
}
/* Expanding over the next vma */
- if (remove_next && file) {
+ if (remove_next && file)
__remove_shared_vm_struct(next, file, mapping);
- } else if (!next) {
- mm->highest_vm_end = vm_end_gap(vma);
- }
if (anon_vma) {
anon_vma_interval_tree_post_update_vma(vma);
@@ -721,7 +611,7 @@ int __vma_adjust(struct vm_area_struct *vma, unsigned long start,
struct vm_area_struct *expand)
{
struct mm_struct *mm = vma->vm_mm;
- struct vm_area_struct *next = vma->vm_next, *orig_vma = vma;
+ struct vm_area_struct *next = vma_next(mm, vma), *orig_vma = vma;
struct address_space *mapping = NULL;
struct rb_root_cached *root = NULL;
struct anon_vma *anon_vma = NULL;
@@ -730,6 +620,7 @@ int __vma_adjust(struct vm_area_struct *vma, unsigned long start,
long adjust_next = 0;
int remove_next = 0;
+ validate_mm(mm);
if (next && !insert) {
struct vm_area_struct *exporter = NULL, *importer = NULL;
@@ -762,7 +653,7 @@ int __vma_adjust(struct vm_area_struct *vma, unsigned long start,
*/
remove_next = 1 + (end > next->vm_end);
VM_WARN_ON(remove_next == 2 &&
- end != next->vm_next->vm_end);
+ end != vma_next(mm, next)->vm_end);
/* trim end to next, for case 6 first pass */
end = next->vm_end;
}
@@ -775,7 +666,7 @@ int __vma_adjust(struct vm_area_struct *vma, unsigned long start,
* next, if the vma overlaps with it.
*/
if (remove_next == 2 && !next->anon_vma)
- exporter = next->vm_next;
+ exporter = vma_next(mm, next);
} else if (end > next->vm_start) {
/*
@@ -867,8 +758,6 @@ int __vma_adjust(struct vm_area_struct *vma, unsigned long start,
else
vma_changed = true;
vma->vm_end = end;
- if (!next)
- mm->highest_vm_end = vm_end_gap(vma);
}
if (vma_changed)
@@ -936,7 +825,7 @@ int __vma_adjust(struct vm_area_struct *vma, unsigned long start,
* "next->vm_prev->vm_end" changed and the
* "vma->vm_next" gap must be updated.
*/
- next = vma->vm_next;
+ next = vma_next(mm, vma);
} else {
/*
* For the scope of the comment "next" and
@@ -954,27 +843,6 @@ int __vma_adjust(struct vm_area_struct *vma, unsigned long start,
remove_next = 1;
end = next->vm_end;
goto again;
- } else if (!next) {
- /*
- * If remove_next == 2 we obviously can't
- * reach this path.
- *
- * If remove_next == 3 we can't reach this
- * path because pre-swap() next is always not
- * NULL. pre-swap() "next" is not being
- * removed and its next->vm_end is not altered
- * (and furthermore "end" already matches
- * next->vm_end in remove_next == 3).
- *
- * We reach this only in the remove_next == 1
- * case if the "next" vma that was removed was
- * the highest vma of the mm. However in such
- * case next->vm_end == "end" and the extended
- * "vma" has vma->vm_end == next->vm_end so
- * mm->highest_vm_end doesn't need any update
- * in remove_next == 1 case.
- */
- VM_WARN_ON(mm->highest_vm_end != vm_end_gap(vma));
}
}
if (insert && file)
@@ -1134,10 +1002,14 @@ struct vm_area_struct *vma_merge(struct mm_struct *mm,
if (vm_flags & VM_SPECIAL)
return NULL;
- next = _vma_next(mm, prev);
+ if (!prev)
+ next = find_vma(mm, 0);
+ else
+ next = vma_next(mm, prev);
+
area = next;
if (area && area->vm_end == end) /* cases 6, 7, 8 */
- next = next->vm_next;
+ next = vma_next(mm, next);
/* verify some invariant that must be enforced by the caller */
VM_WARN_ON(prev && addr <= prev->vm_start);
@@ -1203,6 +1075,7 @@ struct vm_area_struct *vma_merge(struct mm_struct *mm,
return area;
}
+ validate_mm(mm);
return NULL;
}
@@ -1272,17 +1145,20 @@ static struct anon_vma *reusable_anon_vma(struct vm_area_struct *old, struct vm_
struct anon_vma *find_mergeable_anon_vma(struct vm_area_struct *vma)
{
struct anon_vma *anon_vma = NULL;
+ struct vm_area_struct *next, *prev;
/* Try next first. */
- if (vma->vm_next) {
- anon_vma = reusable_anon_vma(vma->vm_next, vma, vma->vm_next);
+ next = vma_next(vma->vm_mm, vma);
+ if (next) {
+ anon_vma = reusable_anon_vma(next, vma, next);
if (anon_vma)
return anon_vma;
}
/* Try prev next. */
- if (vma->vm_prev)
- anon_vma = reusable_anon_vma(vma->vm_prev, vma->vm_prev, vma);
+ prev = vma_prev(vma->vm_mm, vma);
+ if (prev)
+ anon_vma = reusable_anon_vma(prev, prev, vma);
/*
* We might reach here with anon_vma == NULL if we can't find
@@ -2055,7 +1931,7 @@ int expand_upwards(struct vm_area_struct *vma, unsigned long address)
if (gap_addr < address || gap_addr > TASK_SIZE)
gap_addr = TASK_SIZE;
- next = vma->vm_next;
+ next = vma_next(mm, vma);
if (next && next->vm_start < gap_addr && vma_is_accessible(next)) {
if (!(next->vm_flags & VM_GROWSUP))
return -ENOMEM;
@@ -2101,8 +1977,6 @@ int expand_upwards(struct vm_area_struct *vma, unsigned long address)
vma->vm_end = address;
vma_mt_store(mm, vma);
anon_vma_interval_tree_post_update_vma(vma);
- if (!vma->vm_next)
- mm->highest_vm_end = vm_end_gap(vma);
spin_unlock(&mm->page_table_lock);
perf_event_mmap(vma);
@@ -2129,7 +2003,7 @@ int expand_downwards(struct vm_area_struct *vma, unsigned long address)
return -EPERM;
/* Enforce stack_guard_gap */
- prev = vma->vm_prev;
+ prev = vma_prev(mm, vma);
/* Check that both stack segments have the same anon_vma? */
if (prev && !(prev->vm_flags & VM_GROWSDOWN) &&
vma_is_accessible(prev)) {
@@ -2264,21 +2138,21 @@ EXPORT_SYMBOL_GPL(find_extend_vma);
*
* Called with the mm semaphore held.
*/
-static inline void remove_vma_list(struct mm_struct *mm,
- struct vm_area_struct *vma)
+static inline void remove_mt(struct mm_struct *mm, struct ma_state *mas)
{
+ struct vm_area_struct *vma;
unsigned long nr_accounted = 0;
/* Update high watermark before we lower total_vm */
update_hiwater_vm(mm);
- do {
+ mas_for_each(mas, vma, ULONG_MAX) {
long nrpages = vma_pages(vma);
if (vma->vm_flags & VM_ACCOUNT)
nr_accounted += nrpages;
vm_stat_account(mm, vma->vm_flags, -nrpages);
- vma = remove_vma(vma);
- } while (vma);
+ remove_vma(vma);
+ }
vm_unacct_memory(nr_accounted);
validate_mm(mm);
}
@@ -2289,21 +2163,22 @@ static inline void remove_vma_list(struct mm_struct *mm,
* Called with the mm semaphore held.
*/
static void unmap_region(struct mm_struct *mm,
- struct vm_area_struct *vma, struct vm_area_struct *prev,
- unsigned long start, unsigned long end)
+ struct vm_area_struct *vma, struct ma_state *mas,
+ unsigned long start, unsigned long end,
+ struct vm_area_struct *prev, unsigned long max)
{
- struct vm_area_struct *next = _vma_next(mm, prev);
struct mmu_gather tlb;
+ struct ma_state ma_pgtb = *mas;
lru_add_drain();
tlb_gather_mmu(&tlb, mm);
update_hiwater_rss(mm);
- unmap_vmas(&tlb, vma, start, end);
- free_pgtables(&tlb, vma, prev ? prev->vm_end : FIRST_USER_ADDRESS,
- next ? next->vm_start : USER_PGTABLES_CEILING);
+ unmap_vmas(&tlb, vma, mas, start, end);
+ free_pgtables(&tlb, &ma_pgtb, vma,
+ prev ? prev->vm_end : FIRST_USER_ADDRESS,
+ max);
tlb_finish_mmu(&tlb);
}
-
/*
* __split_vma() bypasses sysctl_max_map_count checking. We use this where it
* has already been checked or doesn't make sense to fail.
@@ -2313,7 +2188,6 @@ int __split_vma(struct mm_struct *mm, struct vm_area_struct *vma,
{
struct vm_area_struct *new;
int err;
- validate_mm_mt(mm);
if (vma->vm_ops && vma->vm_ops->may_split) {
err = vma->vm_ops->may_split(vma, addr);
@@ -2366,7 +2240,6 @@ int __split_vma(struct mm_struct *mm, struct vm_area_struct *vma,
mpol_put(vma_policy(new));
out_free_vma:
vm_area_free(new);
- validate_mm_mt(mm);
return err;
}
@@ -2383,24 +2256,31 @@ int split_vma(struct mm_struct *mm, struct vm_area_struct *vma,
return __split_vma(mm, vma, addr, new_below);
}
-static inline int unlock_range(struct vm_area_struct *start,
- struct vm_area_struct **tail, unsigned long limit)
+
+static inline void detach_range(struct mm_struct *mm, struct ma_state *mas,
+ struct ma_state *dst, struct vm_area_struct **vma)
{
- struct mm_struct *mm = start->vm_mm;
- struct vm_area_struct *tmp = start;
+ unsigned long start = dst->index;
+ unsigned long end = dst->last;
int count = 0;
- while (tmp && tmp->vm_start < limit) {
- *tail = tmp;
+ do {
count++;
- if (tmp->vm_flags & VM_LOCKED) {
- mm->locked_vm -= vma_pages(tmp);
- munlock_vma_pages_all(tmp);
+ *vma = mas_prev(mas, start);
+ BUG_ON((*vma)->vm_start < start);
+ BUG_ON((*vma)->vm_end > end + 1);
+ vma_mas_store(*vma, dst);
+ if ((*vma)->vm_flags & VM_LOCKED) {
+ mm->locked_vm -= vma_pages(*vma);
+ munlock_vma_pages_all(*vma);
}
- tmp = tmp->vm_next;
- }
+ } while ((*vma)->vm_start > start);
- return count;
+ /* Drop removed area from the tree */
+ mas->last = end;
+ mas_store_gfp(mas, NULL, GFP_KERNEL);
+ /* Decrement map_count */
+ mm->map_count -= count;
}
/* do_mas_align_munmap() - munmap the aligned region from @start to @end.
@@ -2419,9 +2299,17 @@ static int do_mas_align_munmap(struct ma_state *mas, struct vm_area_struct *vma,
struct mm_struct *mm, unsigned long start, unsigned long end,
struct list_head *uf, bool downgrade)
{
- struct vm_area_struct *prev, *last;
+ struct vm_area_struct *prev, *last, *next = NULL;
+ struct maple_tree mt_detach;
+ unsigned long max = USER_PGTABLES_CEILING;
+ MA_STATE(dst, NULL, start, end - 1);
+ struct ma_state tmp;
/* we have start < vma->vm_end */
+ validate_mm(mm);
+ /* arch_unmap() might do unmaps itself. */
+ arch_unmap(mm, start, end);
+
/*
* If we need to split any vma, do it now to save pain later.
*
@@ -2442,28 +2330,33 @@ static int do_mas_align_munmap(struct ma_state *mas, struct vm_area_struct *vma,
error = __split_vma(mm, vma, start, 0);
if (error)
return error;
+
prev = vma;
- vma = _vma_next(mm, prev);
- mas->index = start;
- mas_reset(mas);
+ mas_set_range(mas, start, end - 1);
+ vma = mas_walk(mas);
+
} else {
- prev = vma->vm_prev;
+ tmp = *mas;
+ prev = mas_prev(&tmp, 0);
}
- if (vma->vm_end >= end)
+ if (end < vma->vm_end) {
last = vma;
- else
- last = find_vma_intersection(mm, end - 1, end);
+ } else {
+ mas_set(mas, end - 1);
+ last = mas_walk(mas);
+ }
/* Does it split the last one? */
if (last && end < last->vm_end) {
- int error = __split_vma(mm, last, end, 1);
+ int error;
+ error = __split_vma(mm, last, end, 1);
if (error)
return error;
- vma = _vma_next(mm, prev);
- mas_reset(mas);
+ mas_set(mas, end - 1);
+ last = mas_walk(mas);
}
-
+ next = mas_next(mas, ULONG_MAX);
if (unlikely(uf)) {
/*
@@ -2481,27 +2374,15 @@ static int do_mas_align_munmap(struct ma_state *mas, struct vm_area_struct *vma,
return error;
}
- /*
- * unlock any mlock()ed ranges before detaching vmas, count the number
- * of VMAs to be dropped, and return the tail entry of the affected
- * area.
- */
- mm->map_count -= unlock_range(vma, &last, end);
- /* Drop removed area from the tree */
- mas_store_gfp(mas, NULL, GFP_KERNEL);
+ /* Point of no return */
+ mas_lock(mas);
+ if (next)
+ max = next->vm_start;
- /* Detach vmas from the MM linked list */
- vma->vm_prev = NULL;
- if (prev)
- prev->vm_next = last->vm_next;
- else
- mm->mmap = last->vm_next;
-
- if (last->vm_next) {
- last->vm_next->vm_prev = prev;
- last->vm_next = NULL;
- } else
- mm->highest_vm_end = prev ? vm_end_gap(prev) : 0;
+ mtree_init(&mt_detach, MAPLE_ALLOC_RANGE);
+ dst.tree = &mt_detach;
+ detach_range(mm, mas, &dst, &vma);
+ mas_unlock(mas);
/*
* Do not downgrade mmap_lock if we are next to VM_GROWSDOWN or
@@ -2509,7 +2390,7 @@ static int do_mas_align_munmap(struct ma_state *mas, struct vm_area_struct *vma,
* down_read(mmap_lock) and collide with the VMA we are about to unmap.
*/
if (downgrade) {
- if (last && (last->vm_flags & VM_GROWSDOWN))
+ if (next && (next->vm_flags & VM_GROWSDOWN))
downgrade = false;
else if (prev && (prev->vm_flags & VM_GROWSUP))
downgrade = false;
@@ -2517,11 +2398,16 @@ static int do_mas_align_munmap(struct ma_state *mas, struct vm_area_struct *vma,
mmap_write_downgrade(mm);
}
- unmap_region(mm, vma, prev, start, end);
+ /* Unmap the region */
+ unmap_region(mm, vma, &dst, start, end, prev, max);
+
+ /* Statistics and freeing VMAs */
+ mas_set(&dst, start);
+ remove_mt(mm, &dst);
- /* Fix up all other VM information */
- remove_vma_list(mm, vma);
+ mtree_destroy(&mt_detach);
+ validate_mm(mm);
return downgrade ? 1 : 0;
}
@@ -2546,16 +2432,14 @@ int do_mas_munmap(struct ma_state *mas, struct mm_struct *mm,
unsigned long end;
struct vm_area_struct *vma;
- if ((offset_in_page(start)) || start > TASK_SIZE || len > TASK_SIZE-start)
+ if ((offset_in_page(start)) || (start > TASK_SIZE) ||
+ (len > TASK_SIZE - start))
return -EINVAL;
end = start + PAGE_ALIGN(len);
if (end == start)
return -EINVAL;
- /* arch_unmap() might do unmaps itself. */
- arch_unmap(mm, start, end);
-
/* Find the first overlapping VMA */
vma = mas_find(mas, end - 1);
if (!vma)
@@ -2574,8 +2458,11 @@ int do_mas_munmap(struct ma_state *mas, struct mm_struct *mm,
int do_munmap(struct mm_struct *mm, unsigned long start, size_t len,
struct list_head *uf)
{
+ int ret;
MA_STATE(mas, &mm->mm_mt, start, start);
- return do_mas_munmap(&mas, mm, start, len, uf, false);
+
+ ret = do_mas_munmap(&mas, mm, start, len, uf, false);
+ return ret;
}
unsigned long mmap_region(struct file *file, unsigned long addr,
@@ -2584,15 +2471,18 @@ unsigned long mmap_region(struct file *file, unsigned long addr,
{
struct mm_struct *mm = current->mm;
struct vm_area_struct *vma = NULL;
- struct vm_area_struct *prev, *next;
+ struct vm_area_struct *prev, *next = NULL;
pgoff_t pglen = len >> PAGE_SHIFT;
unsigned long charged = 0;
unsigned long end = addr + len;
unsigned long merge_start = addr, merge_end = end;
+ unsigned long max = USER_PGTABLES_CEILING;
pgoff_t vm_pgoff;
int error;
+ struct ma_state ma_prev, tmp;
MA_STATE(mas, &mm->mm_mt, addr, end - 1);
+
/* Check against address space limit. */
if (!may_expand_vm(mm, vm_flags, len >> PAGE_SHIFT)) {
unsigned long nr_pages;
@@ -2608,57 +2498,66 @@ unsigned long mmap_region(struct file *file, unsigned long addr,
return -ENOMEM;
}
+ validate_mm(mm);
/* Unmap any existing mapping in the area */
- if (do_mas_munmap(&mas, mm, addr, len, uf, false))
+ if (do_mas_munmap(&mas, mm, addr, len, uf, false)) {
return -ENOMEM;
+ }
/*
* Private writable mapping: check memory availability
*/
if (accountable_mapping(file, vm_flags)) {
charged = len >> PAGE_SHIFT;
- if (security_vm_enough_memory_mm(mm, charged))
+ if (security_vm_enough_memory_mm(mm, charged)) {
return -ENOMEM;
+ }
vm_flags |= VM_ACCOUNT;
}
+ mas_set_range(&mas, addr, end - 1);
+ mas_walk(&mas); // Walk to the empty area (munmapped above)
+ ma_prev = mas;
+ prev = mas_prev(&ma_prev, 0);
- if (vm_flags & VM_SPECIAL) {
- prev = mas_prev(&mas, 0);
+ if (vm_flags & VM_SPECIAL)
goto cannot_expand;
- }
/* Attempt to expand an old mapping */
/* Check next */
- next = mas_next(&mas, ULONG_MAX);
- if (next && next->vm_start == end && vma_policy(next) &&
- can_vma_merge_before(next, vm_flags, NULL, file, pgoff+pglen,
- NULL_VM_UFFD_CTX)) {
- merge_end = next->vm_end;
- vma = next;
- vm_pgoff = next->vm_pgoff - pglen;
+ tmp = mas;
+ next = mas_next(&tmp, ULONG_MAX);
+ if (next) {
+ max = next->vm_start;
+ if (next->vm_start == end && vma_policy(next) &&
+ can_vma_merge_before(next, vm_flags, NULL, file,
+ pgoff + pglen, NULL_VM_UFFD_CTX)) {
+ /* Try to expand next back over the requested area */
+ merge_end = next->vm_end;
+ vma = next;
+ vm_pgoff = next->vm_pgoff - pglen;
+ }
}
/* Check prev */
- prev = mas_prev(&mas, 0);
if (prev && prev->vm_end == addr && !vma_policy(prev) &&
can_vma_merge_after(prev, vm_flags, NULL, file, pgoff,
NULL_VM_UFFD_CTX)) {
+ /* Try to expand the prev over the requested area */
merge_start = prev->vm_start;
vma = prev;
+ mas = ma_prev;
vm_pgoff = prev->vm_pgoff;
}
-
/* Actually expand, if possible */
if (vma &&
!vma_expand(&mas, vma, merge_start, merge_end, vm_pgoff, next)) {
- khugepaged_enter_vma_merge(prev, vm_flags);
+ khugepaged_enter_vma_merge(vma, vm_flags);
goto expanded;
}
- mas_set_range(&mas, addr, end - 1);
cannot_expand:
/*
* Determine the object being mapped and call the appropriate
@@ -2704,9 +2603,12 @@ unsigned long mmap_region(struct file *file, unsigned long addr,
* Answer: Yes, several device drivers can do it in their
* f_op->mmap method. -DaveM
*/
- WARN_ON_ONCE(addr != vma->vm_start);
+ if (addr != vma->vm_start) {
+ WARN_ON_ONCE(addr != vma->vm_start);
+ addr = vma->vm_start;
+ mas_set_range(&mas, addr, end - 1);
+ }
- addr = vma->vm_start;
/* If vm_flags changed after call_mmap(), we should try merge vma again
* as we may succeed this time.
@@ -2717,7 +2619,7 @@ unsigned long mmap_region(struct file *file, unsigned long addr,
pgoff, NULL_VM_UFFD_CTX))) {
merge_start = prev->vm_start;
vm_pgoff = prev->vm_pgoff;
- if (!vma_expand(&mas, prev, merge_start, merge_end,
+ if (!vma_expand(&ma_prev, prev, merge_start, merge_end,
vm_pgoff, next)) {
/* ->mmap() can change vma->vm_file and fput the original file. So
* fput the vma->vm_file here or we would add an extra fput for file
@@ -2742,6 +2644,7 @@ unsigned long mmap_region(struct file *file, unsigned long addr,
goto free_vma;
} else {
vma_set_anonymous(vma);
+ vma->vm_pgoff = vma->vm_start >> PAGE_SHIFT;
}
/* Allow architectures to sanity-check the vm_flags */
@@ -2753,9 +2656,8 @@ unsigned long mmap_region(struct file *file, unsigned long addr,
goto free_vma;
}
- mas.index = mas.last = addr;
- mas_walk(&mas);
- vma_mas_link(mm, vma, &mas, prev);
+ vma_mas_link(mm, vma, &mas);
+
/* Once vma denies write, undo our temporary denial count */
if (file) {
unmap_writable:
@@ -2791,6 +2693,7 @@ unsigned long mmap_region(struct file *file, unsigned long addr,
vma->vm_flags |= VM_SOFTDIRTY;
vma_set_page_prot(vma);
+ validate_mm(mm);
return addr;
@@ -2799,7 +2702,8 @@ unsigned long mmap_region(struct file *file, unsigned long addr,
vma->vm_file = NULL;
/* Undo any partial mapping done by a device driver. */
- unmap_region(mm, vma, prev, vma->vm_start, vma->vm_end);
+ mas_set_range(&mas, addr, end - 1);
+ unmap_region(mm, vma, &mas, vma->vm_start, vma->vm_end, prev, max);
charged = 0;
if (vm_flags & VM_SHARED)
mapping_unmap_writable(file->f_mapping);
@@ -2823,7 +2727,6 @@ static int __vm_munmap(unsigned long start, size_t len, bool downgrade)
if (mmap_write_lock_killable(mm))
return -EINTR;
-
ret = do_mas_munmap(&mas, mm, start, len, &uf, downgrade);
/*
* Returning 1 indicates mmap_lock is downgraded.
@@ -2866,15 +2769,16 @@ SYSCALL_DEFINE5(remap_file_pages, unsigned long, start, unsigned long, size,
unsigned long populate = 0;
unsigned long ret = -EINVAL;
struct file *file;
+ MA_STATE(mas, &mm->mm_mt, start, start);
pr_warn_once("%s (%d) uses deprecated remap_file_pages() syscall. See Documentation/vm/remap_file_pages.rst.\n",
current->comm, current->pid);
if (prot)
return ret;
+
start = start & PAGE_MASK;
size = size & PAGE_MASK;
-
if (start + size <= start)
return ret;
@@ -2885,20 +2789,22 @@ SYSCALL_DEFINE5(remap_file_pages, unsigned long, start, unsigned long, size,
if (mmap_write_lock_killable(mm))
return -EINTR;
- vma = find_vma(mm, start);
+ mas_set(&mas, start);
+ vma = mas_walk(&mas);
if (!vma || !(vma->vm_flags & VM_SHARED))
goto out;
- if (start < vma->vm_start)
+ if (!vma->vm_file)
goto out;
if (start + size > vma->vm_end) {
- struct vm_area_struct *next;
+ struct vm_area_struct *prev, *next;
- for (next = vma->vm_next; next; next = next->vm_next) {
+ prev = vma;
+ mas_for_each(&mas, next, start + size) {
/* hole between vmas ? */
- if (next->vm_start != next->vm_prev->vm_end)
+ if (next->vm_start != prev->vm_end)
goto out;
if (next->vm_file != vma->vm_file)
@@ -2909,6 +2815,8 @@ SYSCALL_DEFINE5(remap_file_pages, unsigned long, start, unsigned long, size,
if (start + size <= next->vm_end)
break;
+
+ prev = next;
}
if (!next)
@@ -2954,9 +2862,10 @@ static int do_brk_munmap(struct ma_state *mas, struct vm_area_struct *vma,
struct list_head *uf)
{
struct mm_struct *mm = vma->vm_mm;
- struct vm_area_struct unmap;
+ struct vm_area_struct unmap, *next;
unsigned long unmap_pages;
int ret;
+ struct ma_state ma_next;
arch_unmap(mm, newbrk, oldbrk);
@@ -2972,11 +2881,17 @@ static int do_brk_munmap(struct ma_state *mas, struct vm_area_struct *vma,
vma_init(&unmap, mm);
unmap.vm_start = newbrk;
unmap.vm_end = oldbrk;
+ unmap.vm_pgoff = newbrk >> PAGE_SHIFT;
+ if (vma->anon_vma)
+ vma_set_anonymous(&unmap);
+
ret = userfaultfd_unmap_prep(&unmap, newbrk, oldbrk, uf);
if (ret)
return ret;
- ret = 1;
+ ret = 1;
+ ma_next = *mas;
+ next = mas_next(&ma_next, ULONG_MAX);
// Change the oldbrk of vma to the newbrk of the munmap area
vma_adjust_trans_huge(vma, vma->vm_start, newbrk, 0);
if (vma->anon_vma) {
@@ -2984,15 +2899,16 @@ static int do_brk_munmap(struct ma_state *mas, struct vm_area_struct *vma,
anon_vma_interval_tree_pre_update_vma(vma);
}
- vma->vm_end = newbrk;
if (vma_mas_remove(&unmap, mas))
goto mas_store_fail;
+ vma->vm_end = newbrk;
if (vma->anon_vma) {
anon_vma_interval_tree_post_update_vma(vma);
anon_vma_unlock_write(vma->anon_vma);
}
+ validate_mm(mm);
unmap_pages = vma_pages(&unmap);
if (unmap.vm_flags & VM_LOCKED) {
mm->locked_vm -= unmap_pages;
@@ -3000,14 +2916,15 @@ static int do_brk_munmap(struct ma_state *mas, struct vm_area_struct *vma,
}
mmap_write_downgrade(mm);
- unmap_region(mm, &unmap, vma, newbrk, oldbrk);
+ unmap_region(mm, &unmap, mas, newbrk, oldbrk, vma,
+ next ? next->vm_start : 0);
/* Statistics */
vm_stat_account(mm, unmap.vm_flags, -unmap_pages);
if (unmap.vm_flags & VM_ACCOUNT)
vm_unacct_memory(unmap_pages);
munmap_full_vma:
- validate_mm_mt(mm);
+ validate_mm(mm);
return ret;
mas_store_fail:
@@ -3031,15 +2948,15 @@ static int do_brk_munmap(struct ma_state *mas, struct vm_area_struct *vma,
* do not match then create a new anonymous VMA. Eventually we may be able to
* do some brk-specific accounting here.
*/
-static int do_brk_flags(struct ma_state *mas, struct vm_area_struct **brkvma,
+static int do_brk_flags(struct ma_state *mas, struct ma_state *ma_prev,
+ struct vm_area_struct **brkvma,
unsigned long addr, unsigned long len,
unsigned long flags)
{
struct mm_struct *mm = current->mm;
- struct vm_area_struct *prev = NULL, *vma;
+ struct vm_area_struct *vma;
int error;
unsigned long mapped_addr;
- validate_mm_mt(mm);
/* Until we need other flags, refuse anything except VM_EXEC. */
if ((flags & (~VM_EXEC)) != 0)
@@ -3064,7 +2981,6 @@ static int do_brk_flags(struct ma_state *mas, struct vm_area_struct **brkvma,
if (security_vm_enough_memory_mm(mm, len >> PAGE_SHIFT))
return -ENOMEM;
- mas->last = addr + len - 1;
if (*brkvma) {
vma = *brkvma;
/* Expand the existing vma if possible; almost never a singular
@@ -3073,17 +2989,21 @@ static int do_brk_flags(struct ma_state *mas, struct vm_area_struct **brkvma,
if ((!vma->anon_vma ||
list_is_singular(&vma->anon_vma_chain)) &&
((vma->vm_flags & ~VM_SOFTDIRTY) == flags)){
- mas->index = vma->vm_start;
+ ma_prev->index = vma->vm_start;
+ ma_prev->last = addr + len - 1;
vma_adjust_trans_huge(vma, addr, addr + len, 0);
if (vma->anon_vma) {
anon_vma_lock_write(vma->anon_vma);
anon_vma_interval_tree_pre_update_vma(vma);
}
+ mas_lock(ma_prev);
vma->vm_end = addr + len;
vma->vm_flags |= VM_SOFTDIRTY;
- if (mas_store_gfp(mas, vma, GFP_KERNEL))
+ if (mas_store_gfp(ma_prev, vma, GFP_KERNEL)) {
+ mas_unlock(ma_prev);
goto mas_mod_fail;
+ }
if (vma->anon_vma) {
anon_vma_interval_tree_post_update_vma(vma);
@@ -3092,11 +3012,9 @@ static int do_brk_flags(struct ma_state *mas, struct vm_area_struct **brkvma,
khugepaged_enter_vma_merge(vma, flags);
goto out;
}
- prev = vma;
}
- mas->index = addr;
- mas_walk(mas);
+ mas->last = addr + len - 1;
/* create a vma struct for an anonymous mapping */
vma = vm_area_alloc(mm);
if (!vma)
@@ -3111,9 +3029,6 @@ static int do_brk_flags(struct ma_state *mas, struct vm_area_struct **brkvma,
if (vma_mas_store(vma, mas))
goto mas_store_fail;
- if (!prev)
- prev = mas_prev(mas, 0);
-
mm->map_count++;
*brkvma = vma;
out:
@@ -3123,7 +3038,6 @@ static int do_brk_flags(struct ma_state *mas, struct vm_area_struct **brkvma,
if (flags & VM_LOCKED)
mm->locked_vm += (len >> PAGE_SHIFT);
vma->vm_flags |= VM_SOFTDIRTY;
- validate_mm_mt(mm);
return 0;
mas_store_fail:
@@ -3162,7 +3076,7 @@ int vm_brk_flags(unsigned long addr, unsigned long request, unsigned long flags)
// This vma left intentionally blank.
mas_walk(&mas);
- ret = do_brk_flags(&mas, &vma, addr, len, flags);
+ ret = do_brk_flags(&mas, &mas, &vma, addr, len, flags);
populate = ((mm->def_flags & VM_LOCKED) != 0);
mmap_write_unlock(mm);
if (populate && !ret)
@@ -3183,6 +3097,8 @@ void exit_mmap(struct mm_struct *mm)
struct mmu_gather tlb;
struct vm_area_struct *vma;
unsigned long nr_accounted = 0;
+ struct ma_state mas2;
+ MA_STATE(mas, &mm->mm_mt, FIRST_USER_ADDRESS, FIRST_USER_ADDRESS);
/* mm's last user has gone, and its about to be pulled down */
mmu_notifier_release(mm);
@@ -3211,32 +3127,43 @@ void exit_mmap(struct mm_struct *mm)
mmap_write_unlock(mm);
}
- if (mm->locked_vm)
- unlock_range(mm->mmap, &vma, ULONG_MAX);
+ if (mm->locked_vm) {
+ mas_for_each(&mas, vma, ULONG_MAX) {
+ if (vma->vm_flags & VM_LOCKED) {
+ mm->locked_vm -= vma_pages(vma);
+ munlock_vma_pages_all(vma);
+ }
+ }
+ mas_set(&mas, FIRST_USER_ADDRESS);
+ }
arch_exit_mmap(mm);
- vma = mm->mmap;
- if (!vma) /* Can happen if dup_mmap() received an OOM */
+ vma = mas_find(&mas, ULONG_MAX);
+ if (!vma) { /* Can happen if dup_mmap() received an OOM */
+ rcu_read_unlock();
return;
+ }
lru_add_drain();
flush_cache_mm(mm);
tlb_gather_mmu_fullmm(&tlb, mm);
/* update_hiwater_rss(mm) here? but nobody should be looking */
/* Use -1 here to ensure all VMAs in the mm are unmapped */
- unmap_vmas(&tlb, vma, 0, -1);
- free_pgtables(&tlb, vma, FIRST_USER_ADDRESS, USER_PGTABLES_CEILING);
+ mas2 = mas;
+ unmap_vmas(&tlb, vma, &mas, 0, -1);
+ free_pgtables(&tlb, &mas2, vma, FIRST_USER_ADDRESS, USER_PGTABLES_CEILING);
tlb_finish_mmu(&tlb);
/*
* Walk the list again, actually closing and freeing it,
* with preemption enabled, without holding any MM locks.
*/
- while (vma) {
+ mas_set(&mas, 0);
+ mas_for_each(&mas, vma, ULONG_MAX) {
if (vma->vm_flags & VM_ACCOUNT)
nr_accounted += vma_pages(vma);
- vma = remove_vma(vma);
+ remove_vma(vma);
cond_resched();
}
@@ -3251,9 +3178,7 @@ void exit_mmap(struct mm_struct *mm)
*/
int insert_vm_struct(struct mm_struct *mm, struct vm_area_struct *vma)
{
- struct vm_area_struct *prev;
-
- if (range_has_overlap(mm, vma->vm_start, vma->vm_end, &prev))
+ if (find_vma_intersection(mm, vma->vm_start, vma->vm_end))
return -ENOMEM;
if ((vma->vm_flags & VM_ACCOUNT) &&
@@ -3277,7 +3202,7 @@ int insert_vm_struct(struct mm_struct *mm, struct vm_area_struct *vma)
vma->vm_pgoff = vma->vm_start >> PAGE_SHIFT;
}
- vma_link(mm, vma, prev);
+ vma_link(mm, vma);
return 0;
}
@@ -3295,7 +3220,6 @@ struct vm_area_struct *copy_vma(struct vm_area_struct **vmap,
struct vm_area_struct *new_vma, *prev;
bool faulted_in_anon_vma = true;
- validate_mm_mt(mm);
/*
* If anonymous vma has not yet been faulted, update new pgoff
* to match new location, to increase its chance of merging.
@@ -3348,10 +3272,9 @@ struct vm_area_struct *copy_vma(struct vm_area_struct **vmap,
get_file(new_vma->vm_file);
if (new_vma->vm_ops && new_vma->vm_ops->open)
new_vma->vm_ops->open(new_vma);
- vma_link(mm, new_vma, prev);
+ vma_link(mm, new_vma);
*need_rmap_locks = false;
}
- validate_mm_mt(mm);
return new_vma;
out_free_mempol:
@@ -3359,7 +3282,6 @@ struct vm_area_struct *copy_vma(struct vm_area_struct **vmap,
out_free_vma:
vm_area_free(new_vma);
out:
- validate_mm_mt(mm);
return NULL;
}
@@ -3496,7 +3418,6 @@ static struct vm_area_struct *__install_special_mapping(
int ret;
struct vm_area_struct *vma;
- validate_mm_mt(mm);
vma = vm_area_alloc(mm);
if (unlikely(vma == NULL))
return ERR_PTR(-ENOMEM);
@@ -3518,12 +3439,10 @@ static struct vm_area_struct *__install_special_mapping(
perf_event_mmap(vma);
- validate_mm_mt(mm);
return vma;
out:
vm_area_free(vma);
- validate_mm_mt(mm);
return ERR_PTR(ret);
}
@@ -3648,12 +3567,14 @@ int mm_take_all_locks(struct mm_struct *mm)
{
struct vm_area_struct *vma;
struct anon_vma_chain *avc;
+ MA_STATE(mas, &mm->mm_mt, 0, 0);
BUG_ON(mmap_read_trylock(mm));
mutex_lock(&mm_all_locks_mutex);
+ rcu_read_lock();
- for (vma = mm->mmap; vma; vma = vma->vm_next) {
+ mas_for_each(&mas, vma, ULONG_MAX) {
if (signal_pending(current))
goto out_unlock;
if (vma->vm_file && vma->vm_file->f_mapping &&
@@ -3661,7 +3582,8 @@ int mm_take_all_locks(struct mm_struct *mm)
vm_lock_mapping(mm, vma->vm_file->f_mapping);
}
- for (vma = mm->mmap; vma; vma = vma->vm_next) {
+ mas_set(&mas, 0);
+ mas_for_each(&mas, vma, ULONG_MAX) {
if (signal_pending(current))
goto out_unlock;
if (vma->vm_file && vma->vm_file->f_mapping &&
@@ -3669,7 +3591,8 @@ int mm_take_all_locks(struct mm_struct *mm)
vm_lock_mapping(mm, vma->vm_file->f_mapping);
}
- for (vma = mm->mmap; vma; vma = vma->vm_next) {
+ mas_set(&mas, 0);
+ mas_for_each(&mas, vma, ULONG_MAX) {
if (signal_pending(current))
goto out_unlock;
if (vma->anon_vma)
@@ -3677,9 +3600,11 @@ int mm_take_all_locks(struct mm_struct *mm)
vm_lock_anon_vma(mm, avc->anon_vma);
}
+ rcu_read_unlock();
return 0;
out_unlock:
+ rcu_read_unlock();
mm_drop_all_locks(mm);
return -EINTR;
}
@@ -3728,17 +3653,21 @@ void mm_drop_all_locks(struct mm_struct *mm)
{
struct vm_area_struct *vma;
struct anon_vma_chain *avc;
+ MA_STATE(mas, &mm->mm_mt, 0, 0);
BUG_ON(mmap_read_trylock(mm));
BUG_ON(!mutex_is_locked(&mm_all_locks_mutex));
- for (vma = mm->mmap; vma; vma = vma->vm_next) {
+
+ rcu_read_lock();
+ mas_for_each(&mas, vma, ULONG_MAX) {
if (vma->anon_vma)
list_for_each_entry(avc, &vma->anon_vma_chain, same_vma)
vm_unlock_anon_vma(avc->anon_vma);
if (vma->vm_file && vma->vm_file->f_mapping)
vm_unlock_mapping(vma->vm_file->f_mapping);
}
+ rcu_read_unlock();
mutex_unlock(&mm_all_locks_mutex);
}
diff --git a/mm/nommu.c b/mm/nommu.c
index 916038bafc65..a99e276445ce 100644
--- a/mm/nommu.c
+++ b/mm/nommu.c
@@ -1428,7 +1428,8 @@ int do_munmap(struct mm_struct *mm, unsigned long start, size_t len, struct list
return -EINVAL;
if (end == vma->vm_end)
goto erase_whole_vma;
- vma = vma_next(mm, vma);
+
+ vma = vma_next(mm, vma);
} while (vma);
return -EINVAL;
} else {
@@ -1479,18 +1480,23 @@ SYSCALL_DEFINE2(munmap, unsigned long, addr, size_t, len)
void exit_mmap(struct mm_struct *mm)
{
struct vm_area_struct *vma;
+ MA_STATE(mas, NULL, 0, 0);
if (!mm)
return;
+ mas.tree = &mm->mm_mt;
mm->total_vm = 0;
-
- while ((vma = mm->mmap)) {
- mm->mmap = vma_next(mm, vma);
+ rcu_read_lock();
+ mas_for_each(&mas, vma, ULONG_MAX) {
delete_vma_from_mm(vma);
delete_vma(mm, vma);
+ rcu_read_unlock();
+ mas_pause(&mas);
cond_resched();
+ rcu_read_lock();
}
+ rcu_read_unlock();
}
int vm_brk(unsigned long addr, unsigned long len)
--
2.30.2