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    Subject[PATCH v3 06/66] mm: Start tracking VMAs with maple tree
    Date
    From: "Liam R. Howlett" <Liam.Howlett@Oracle.com>

    Start tracking the VMAs with the new maple tree structure in parallel
    with the rb_tree. Add debug and trace events for maple tree operations
    and duplicate the rb_tree that is created on forks into the maple tree.

    In this commit, the maple tree is added to the mm_struct including the
    mm_init struct, added support in required mm/mmap functions, added
    tracking in kernel/fork for process forking, and used to find the
    unmapped_area and checked against what the rbtree finds.

    Signed-off-by: Liam R. Howlett <Liam.Howlett@Oracle.com>
    ---
    arch/x86/kernel/tboot.c | 1 +
    drivers/firmware/efi/efi.c | 1 +
    include/linux/mm.h | 2 +
    include/linux/mm_types.h | 2 +
    include/trace/events/mmap.h | 71 +++++++++++
    init/main.c | 2 +
    kernel/fork.c | 4 +
    mm/init-mm.c | 2 +
    mm/internal.h | 77 ++++++++++++
    mm/mmap.c | 229 +++++++++++++++++++++++++++++++++++-
    10 files changed, 389 insertions(+), 2 deletions(-)

    diff --git a/arch/x86/kernel/tboot.c b/arch/x86/kernel/tboot.c
    index f9af561c3cd4..6f978f722dff 100644
    --- a/arch/x86/kernel/tboot.c
    +++ b/arch/x86/kernel/tboot.c
    @@ -98,6 +98,7 @@ void __init tboot_probe(void)
    static pgd_t *tboot_pg_dir;
    static struct mm_struct tboot_mm = {
    .mm_rb = RB_ROOT,
    + .mm_mt = MTREE_INIT(mm_mt, MAPLE_ALLOC_RANGE),
    .pgd = swapper_pg_dir,
    .mm_users = ATOMIC_INIT(2),
    .mm_count = ATOMIC_INIT(1),
    diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c
    index 847f33ffc4ae..1aaecca36e23 100644
    --- a/drivers/firmware/efi/efi.c
    +++ b/drivers/firmware/efi/efi.c
    @@ -55,6 +55,7 @@ static unsigned long __initdata rt_prop = EFI_INVALID_TABLE_ADDR;

    struct mm_struct efi_mm = {
    .mm_rb = RB_ROOT,
    + .mm_mt = MTREE_INIT(mm_mt, MAPLE_ALLOC_RANGE),
    .mm_users = ATOMIC_INIT(2),
    .mm_count = ATOMIC_INIT(1),
    .write_protect_seq = SEQCNT_ZERO(efi_mm.write_protect_seq),
    diff --git a/include/linux/mm.h b/include/linux/mm.h
    index 73a52aba448f..df592bf937f9 100644
    --- a/include/linux/mm.h
    +++ b/include/linux/mm.h
    @@ -2500,6 +2500,8 @@ extern bool arch_has_descending_max_zone_pfns(void);
    /* nommu.c */
    extern atomic_long_t mmap_pages_allocated;
    extern int nommu_shrink_inode_mappings(struct inode *, size_t, size_t);
    +/* maple_tree */
    +void vma_store(struct mm_struct *mm, struct vm_area_struct *vma);

    /* interval_tree.c */
    void vma_interval_tree_insert(struct vm_area_struct *node,
    diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
    index 7f8ee09c711f..2fc27dff8b6c 100644
    --- a/include/linux/mm_types.h
    +++ b/include/linux/mm_types.h
    @@ -8,6 +8,7 @@
    #include <linux/list.h>
    #include <linux/spinlock.h>
    #include <linux/rbtree.h>
    +#include <linux/maple_tree.h>
    #include <linux/rwsem.h>
    #include <linux/completion.h>
    #include <linux/cpumask.h>
    @@ -402,6 +403,7 @@ struct kioctx_table;
    struct mm_struct {
    struct {
    struct vm_area_struct *mmap; /* list of VMAs */
    + struct maple_tree mm_mt;
    struct rb_root mm_rb;
    u64 vmacache_seqnum; /* per-thread vmacache */
    #ifdef CONFIG_MMU
    diff --git a/include/trace/events/mmap.h b/include/trace/events/mmap.h
    index 4661f7ba07c0..4ffe3d348966 100644
    --- a/include/trace/events/mmap.h
    +++ b/include/trace/events/mmap.h
    @@ -42,6 +42,77 @@ TRACE_EVENT(vm_unmapped_area,
    __entry->low_limit, __entry->high_limit, __entry->align_mask,
    __entry->align_offset)
    );
    +
    +TRACE_EVENT(vma_mt_szero,
    + TP_PROTO(struct mm_struct *mm, unsigned long start,
    + unsigned long end),
    +
    + TP_ARGS(mm, start, end),
    +
    + TP_STRUCT__entry(
    + __field(struct mm_struct*, mm)
    + __field(unsigned long, start)
    + __field(unsigned long, end)
    + ),
    +
    + TP_fast_assign(
    + __entry->mm = mm;
    + __entry->start = start;
    + __entry->end = end - 1;
    + ),
    +
    + TP_printk("mt_mod %px, (NULL), SNULL, %lu, %lu,",
    + __entry->mm,
    + (unsigned long) __entry->start,
    + (unsigned long) __entry->end
    + )
    +);
    +
    +TRACE_EVENT(vma_mt_store,
    + TP_PROTO(struct mm_struct *mm, struct vm_area_struct *vma),
    +
    + TP_ARGS(mm, vma),
    +
    + TP_STRUCT__entry(
    + __field(struct mm_struct*, mm)
    + __field(struct vm_area_struct*, vma)
    + __field(unsigned long, vm_start)
    + __field(unsigned long, vm_end)
    + ),
    +
    + TP_fast_assign(
    + __entry->mm = mm;
    + __entry->vma = vma;
    + __entry->vm_start = vma->vm_start;
    + __entry->vm_end = vma->vm_end - 1;
    + ),
    +
    + TP_printk("mt_mod %px, (%px), STORE, %lu, %lu,",
    + __entry->mm, __entry->vma,
    + (unsigned long) __entry->vm_start,
    + (unsigned long) __entry->vm_end
    + )
    +);
    +
    +
    +TRACE_EVENT(exit_mmap,
    + TP_PROTO(struct mm_struct *mm),
    +
    + TP_ARGS(mm),
    +
    + TP_STRUCT__entry(
    + __field(struct mm_struct*, mm)
    + ),
    +
    + TP_fast_assign(
    + __entry->mm = mm;
    + ),
    +
    + TP_printk("mt_mod %px, DESTROY\n",
    + __entry->mm
    + )
    +);
    +
    #endif

    /* This part must be outside protection */
    diff --git a/init/main.c b/init/main.c
    index 81a79a77db46..1cc4c69a5a55 100644
    --- a/init/main.c
    +++ b/init/main.c
    @@ -116,6 +116,7 @@ static int kernel_init(void *);

    extern void init_IRQ(void);
    extern void radix_tree_init(void);
    +extern void maple_tree_init(void);

    /*
    * Debug helper: via this flag we know that we are in 'early bootup code'
    @@ -1003,6 +1004,7 @@ asmlinkage __visible void __init __no_sanitize_address start_kernel(void)
    "Interrupts were enabled *very* early, fixing it\n"))
    local_irq_disable();
    radix_tree_init();
    + maple_tree_init();

    /*
    * Set up housekeeping before setting up workqueues to allow the unbound
    diff --git a/kernel/fork.c b/kernel/fork.c
    index 38681ad44c76..e8d602de40e8 100644
    --- a/kernel/fork.c
    +++ b/kernel/fork.c
    @@ -605,6 +605,9 @@ static __latent_entropy int dup_mmap(struct mm_struct *mm,
    rb_link = &tmp->vm_rb.rb_right;
    rb_parent = &tmp->vm_rb;

    + /* Link the vma into the MT */
    + vma_store(mm, tmp);
    +
    mm->map_count++;
    if (!(tmp->vm_flags & VM_WIPEONFORK))
    retval = copy_page_range(tmp, mpnt);
    @@ -1038,6 +1041,7 @@ static struct mm_struct *mm_init(struct mm_struct *mm, struct task_struct *p,
    {
    mm->mmap = NULL;
    mm->mm_rb = RB_ROOT;
    + mt_init_flags(&mm->mm_mt, MAPLE_ALLOC_RANGE);
    mm->vmacache_seqnum = 0;
    atomic_set(&mm->mm_users, 1);
    atomic_set(&mm->mm_count, 1);
    diff --git a/mm/init-mm.c b/mm/init-mm.c
    index b4a6f38fb51d..e4a058f7e8b6 100644
    --- a/mm/init-mm.c
    +++ b/mm/init-mm.c
    @@ -1,6 +1,7 @@
    // SPDX-License-Identifier: GPL-2.0
    #include <linux/mm_types.h>
    #include <linux/rbtree.h>
    +#include <linux/maple_tree.h>
    #include <linux/rwsem.h>
    #include <linux/spinlock.h>
    #include <linux/list.h>
    @@ -28,6 +29,7 @@
    */
    struct mm_struct init_mm = {
    .mm_rb = RB_ROOT,
    + .mm_mt = MTREE_INIT(mm_mt, MAPLE_ALLOC_RANGE),
    .pgd = swapper_pg_dir,
    .mm_users = ATOMIC_INIT(2),
    .mm_count = ATOMIC_INIT(1),
    diff --git a/mm/internal.h b/mm/internal.h
    index cf3cb933eba3..3f45e1d0c02b 100644
    --- a/mm/internal.h
    +++ b/mm/internal.h
    @@ -340,6 +340,83 @@ static inline bool is_data_mapping(vm_flags_t flags)
    return (flags & (VM_WRITE | VM_SHARED | VM_STACK)) == VM_WRITE;
    }

    +/* Maple tree operations using VMAs */
    +/*
    + * vma_mas_store() - Store a VMA in the maple tree.
    + * @vma: The vm_area_struct
    + * @mas: The maple state
    + *
    + * Efficient way to store a VMA in the maple tree when the @mas has already
    + * walked to the correct location.
    + *
    + * Note: the end address is inclusive in the maple tree.
    + */
    +static inline int vma_mas_store(struct vm_area_struct *vma, struct ma_state *mas)
    +{
    + int ret;
    +
    +#ifdef CONFIG_DEBUG_MAPLE_TREE
    + /* Make sure no VMAs are about to be lost. */
    + MA_STATE(test, mas->tree, vma->vm_start, vma->vm_end - 1);
    + struct vm_area_struct *vma_mas;
    + int count = 0;
    +
    + mas_for_each(&test, vma_mas, vma->vm_end - 1) {
    + /* Rule out vma_expand */
    + if ((vma->vm_start != vma_mas->vm_start) &&
    + (vma->vm_end != vma_mas->vm_end))
    + count++;
    + }
    +
    + BUG_ON(count);
    +
    + BUG_ON(mas->min > vma->vm_start);
    + BUG_ON(mas->index > vma->vm_start);
    +#endif
    + mas->index = vma->vm_start;
    + mas->last = vma->vm_end - 1;
    + mas_lock(mas);
    + ret = mas_store_gfp(mas, vma, GFP_KERNEL);
    + mas_unlock(mas);
    + return ret;
    +}
    +
    +/*
    + * vma_mas_remove() - Remove a VMA from the maple tree.
    + * @vma: The vm_area_struct
    + * @mas: The maple state
    + *
    + * Efficient way to remove a VMA from the maple tree when the @mas has already
    + * been established and points to the correct location.
    + * Note: the end address is inclusive in the maple tree.
    + */
    +static inline int vma_mas_remove(struct vm_area_struct *vma, struct ma_state *mas)
    +{
    + int ret;
    +
    +#ifdef CONFIG_DEBUG_MAPLE_TREE
    + /* Make sure no VMAs are about to be lost. */
    + MA_STATE(test, mas->tree, vma->vm_start, vma->vm_end - 1);
    + struct vm_area_struct *vma_mas;
    + int count = 0;
    +
    + mas_for_each(&test, vma_mas, vma->vm_end - 1)
    + count++;
    +
    + BUG_ON(count != 1);
    +
    + BUG_ON(mas->min > vma->vm_start);
    + BUG_ON(mas->index > vma->vm_start);
    + BUG_ON(mas->min > mas->index);
    +#endif
    + mas->index = vma->vm_start;
    + mas->last = vma->vm_end - 1;
    + mas_lock(mas);
    + ret = mas_store_gfp(mas, NULL, GFP_KERNEL);
    + mas_unlock(mas);
    + return ret;
    +}
    +
    /* mm/util.c */
    void __vma_link_list(struct mm_struct *mm, struct vm_area_struct *vma,
    struct vm_area_struct *prev);
    diff --git a/mm/mmap.c b/mm/mmap.c
    index 88dcc5c25225..b9078e6d7d61 100644
    --- a/mm/mmap.c
    +++ b/mm/mmap.c
    @@ -375,7 +375,73 @@ static int browse_rb(struct mm_struct *mm)
    }
    return bug ? -1 : i;
    }
    +#if defined(CONFIG_DEBUG_MAPLE_TREE)
    +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 next in rb\n");
    + dump_vma(vma->vm_next);
    +#endif
    + 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);
    + pr_emerg("rb vma: %px %lu - %lu\n", vma,
    + vma->vm_start, vma->vm_end);
    + pr_emerg("rb->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);
    +}
    +#else
    +#define validate_mm_mt(root) do { } while (0)
    +#endif
    static void validate_mm_rb(struct rb_root *root, struct vm_area_struct *ignore)
    {
    struct rb_node *nd;
    @@ -430,6 +496,7 @@ static void validate_mm(struct mm_struct *mm)
    }
    #else
    #define validate_mm_rb(root, ignore) do { } while (0)
    +#define validate_mm_mt(root) do { } while (0)
    #define validate_mm(mm) do { } while (0)
    #endif

    @@ -609,6 +676,7 @@ static unsigned long count_vma_pages_range(struct mm_struct *mm,
    unsigned long addr, unsigned long end)
    {
    unsigned long nr_pages = 0;
    + unsigned long nr_mt_pages = 0;
    struct vm_area_struct *vma;

    /* Find first overlapping mapping */
    @@ -630,6 +698,13 @@ static unsigned long count_vma_pages_range(struct mm_struct *mm,
    nr_pages += overlap_len >> PAGE_SHIFT;
    }

    + mt_for_each(&mm->mm_mt, vma, addr, end) {
    + nr_mt_pages +=
    + (min(end, vma->vm_end) - vma->vm_start) >> PAGE_SHIFT;
    + }
    +
    + VM_BUG_ON_MM(nr_pages != nr_mt_pages, mm);
    +
    return nr_pages;
    }

    @@ -674,11 +749,49 @@ static void __vma_link_file(struct vm_area_struct *vma)
    }
    }

    +/*
    + * vma_mt_szero() - Set a given range to zero. Used when modifying a
    + * vm_area_struct start or end.
    + *
    + * @mm: The struct_mm
    + * @start: The start address to zero
    + * @end: The end address to zero.
    + *
    + * Must not hold the maple tree lock.
    + */
    +static inline void vma_mt_szero(struct mm_struct *mm, unsigned long start,
    + unsigned long end)
    +{
    + trace_vma_mt_szero(mm, start, end);
    + mtree_store_range(&mm->mm_mt, start, end - 1, NULL, GFP_KERNEL);
    +}
    +
    +/*
    + * vma_mt_store() - Store a given vm_area_struct in the maple tree.
    + *
    + * @mm: The struct_mm
    + * @vma: The vm_area_struct to store in the maple tree.
    + *
    + * Must not hold the maple tree lock.
    + */
    +static inline
    +void vma_mt_store(struct mm_struct *mm, struct vm_area_struct *vma)
    +{
    + trace_vma_mt_store(mm, vma);
    + mtree_store_range(&mm->mm_mt, vma->vm_start, vma->vm_end - 1, vma,
    + GFP_KERNEL);
    +}
    +
    +void vma_store(struct mm_struct *mm, struct vm_area_struct *vma) {
    + vma_mt_store(mm, vma);
    +}
    +
    static void
    __vma_link(struct mm_struct *mm, struct vm_area_struct *vma,
    struct vm_area_struct *prev, struct rb_node **rb_link,
    struct rb_node *rb_parent)
    {
    + vma_mt_store(mm, vma);
    __vma_link_list(mm, vma, prev);
    __vma_link_rb(mm, vma, rb_link, rb_parent);
    }
    @@ -751,6 +864,9 @@ int __vma_adjust(struct vm_area_struct *vma, unsigned long start,
    long adjust_next = 0;
    int remove_next = 0;

    + validate_mm(mm);
    + validate_mm_mt(mm);
    +
    if (next && !insert) {
    struct vm_area_struct *exporter = NULL, *importer = NULL;

    @@ -876,17 +992,28 @@ int __vma_adjust(struct vm_area_struct *vma, unsigned long start,
    }

    if (start != vma->vm_start) {
    + unsigned long old_start = vma->vm_start;
    vma->vm_start = start;
    + if (old_start < start)
    + vma_mt_szero(mm, old_start, start);
    start_changed = true;
    }
    if (end != vma->vm_end) {
    + unsigned long old_end = vma->vm_end;
    vma->vm_end = end;
    + if (old_end > end)
    + vma_mt_szero(mm, end, old_end);
    end_changed = true;
    }
    +
    + if (end_changed || start_changed)
    + vma_mt_store(mm, vma);
    +
    vma->vm_pgoff = pgoff;
    if (adjust_next) {
    next->vm_start += adjust_next;
    next->vm_pgoff += adjust_next >> PAGE_SHIFT;
    + vma_mt_store(mm, next);
    }

    if (file) {
    @@ -900,6 +1027,8 @@ int __vma_adjust(struct vm_area_struct *vma, unsigned long start,
    /*
    * vma_merge has merged next into vma, and needs
    * us to remove next before dropping the locks.
    + * Since we have expanded over this vma, the maple tree will
    + * have overwritten by storing the value
    */
    if (remove_next != 3)
    __vma_unlink(mm, next, next);
    @@ -1019,6 +1148,7 @@ int __vma_adjust(struct vm_area_struct *vma, unsigned long start,
    uprobe_mmap(insert);

    validate_mm(mm);
    + validate_mm_mt(mm);

    return 0;
    }
    @@ -1166,6 +1296,7 @@ struct vm_area_struct *vma_merge(struct mm_struct *mm,
    struct vm_area_struct *area, *next;
    int err;

    + validate_mm_mt(mm);
    /*
    * We later require that vma->vm_flags == vm_flags,
    * so this tests vma->vm_flags & VM_SPECIAL, too.
    @@ -1241,6 +1372,7 @@ struct vm_area_struct *vma_merge(struct mm_struct *mm,
    khugepaged_enter_vma_merge(area, vm_flags);
    return area;
    }
    + validate_mm_mt(mm);

    return NULL;
    }
    @@ -1723,6 +1855,7 @@ unsigned long mmap_region(struct file *file, unsigned long addr,
    struct rb_node **rb_link, *rb_parent;
    unsigned long charged = 0;

    + validate_mm_mt(mm);
    /* Check against address space limit. */
    if (!may_expand_vm(mm, vm_flags, len >> PAGE_SHIFT)) {
    unsigned long nr_pages;
    @@ -1870,6 +2003,7 @@ unsigned long mmap_region(struct file *file, unsigned long addr,

    vma_set_page_prot(vma);

    + validate_mm_mt(mm);
    return addr;

    unmap_and_free_vma:
    @@ -1886,6 +2020,7 @@ unsigned long mmap_region(struct file *file, unsigned long addr,
    unacct_error:
    if (charged)
    vm_unacct_memory(charged);
    + validate_mm_mt(mm);
    return error;
    }

    @@ -1902,12 +2037,21 @@ static unsigned long unmapped_area(struct vm_unmapped_area_info *info)
    struct mm_struct *mm = current->mm;
    struct vm_area_struct *vma;
    unsigned long length, low_limit, high_limit, gap_start, gap_end;
    + unsigned long gap;
    + MA_STATE(mas, &mm->mm_mt, 0, 0);

    /* Adjust search length to account for worst case alignment overhead */
    length = info->length + info->align_mask;
    if (length < info->length)
    return -ENOMEM;

    + rcu_read_lock();
    + mas_empty_area_rev(&mas, info->low_limit, info->high_limit - 1,
    + length);
    + rcu_read_unlock();
    + gap = mas.index;
    + gap += (info->align_offset - gap) & info->align_mask;
    +
    /* Adjust search limits by the desired length */
    if (info->high_limit < length)
    return -ENOMEM;
    @@ -1989,20 +2133,39 @@ static unsigned long unmapped_area(struct vm_unmapped_area_info *info)

    VM_BUG_ON(gap_start + info->length > info->high_limit);
    VM_BUG_ON(gap_start + info->length > gap_end);
    +
    + VM_BUG_ON(gap != gap_start);
    return gap_start;
    }

    +static inline unsigned long top_area_aligned(struct vm_unmapped_area_info *info,
    + unsigned long end)
    +{
    + return (end - info->length - info->align_offset) & (~info->align_mask);
    +}
    +
    static unsigned long unmapped_area_topdown(struct vm_unmapped_area_info *info)
    {
    struct mm_struct *mm = current->mm;
    - struct vm_area_struct *vma;
    + struct vm_area_struct *vma = NULL;
    unsigned long length, low_limit, high_limit, gap_start, gap_end;
    + unsigned long gap;
    +
    + MA_STATE(mas, &mm->mm_mt, 0, 0);
    + validate_mm_mt(mm);

    /* Adjust search length to account for worst case alignment overhead */
    length = info->length + info->align_mask;
    if (length < info->length)
    return -ENOMEM;

    + rcu_read_lock();
    + mas_empty_area_rev(&mas, info->low_limit, info->high_limit - 1,
    + length);
    + rcu_read_unlock();
    + gap = (mas.index + info->align_mask) & ~info->align_mask;
    + gap -= info->align_offset & info->align_mask;
    +
    /*
    * Adjust search limits by the desired length.
    * See implementation comment at top of unmapped_area().
    @@ -2088,6 +2251,32 @@ static unsigned long unmapped_area_topdown(struct vm_unmapped_area_info *info)

    VM_BUG_ON(gap_end < info->low_limit);
    VM_BUG_ON(gap_end < gap_start);
    +
    + if (gap != gap_end) {
    + pr_err("%s: %px Gap was found: mt %lu gap_end %lu\n", __func__,
    + mm, gap, gap_end);
    + pr_err("window was %lu - %lu size %lu\n", info->high_limit,
    + info->low_limit, length);
    + pr_err("mas.min %lu max %lu mas.last %lu\n", mas.min, mas.max,
    + mas.last);
    + pr_err("mas.index %lu align mask %lu offset %lu\n", mas.index,
    + info->align_mask, info->align_offset);
    + pr_err("rb_find_vma find on %lu => %px (%px)\n", mas.index,
    + find_vma(mm, mas.index), vma);
    +#if defined(CONFIG_DEBUG_MAPLE_TREE)
    + mt_dump(&mm->mm_mt);
    +#endif
    + {
    + struct vm_area_struct *dv = mm->mmap;
    +
    + while (dv) {
    + printk("vma %px %lu-%lu\n", dv, dv->vm_start, dv->vm_end);
    + dv = dv->vm_next;
    + }
    + }
    + VM_BUG_ON(gap != gap_end);
    + }
    +
    return gap_end;
    }

    @@ -2301,7 +2490,6 @@ struct vm_area_struct *find_vma(struct mm_struct *mm, unsigned long addr)
    vmacache_update(addr, vma);
    return vma;
    }
    -
    EXPORT_SYMBOL(find_vma);

    /*
    @@ -2382,6 +2570,7 @@ int expand_upwards(struct vm_area_struct *vma, unsigned long address)
    unsigned long gap_addr;
    int error = 0;

    + validate_mm_mt(mm);
    if (!(vma->vm_flags & VM_GROWSUP))
    return -EFAULT;

    @@ -2458,6 +2647,7 @@ int expand_upwards(struct vm_area_struct *vma, unsigned long address)
    anon_vma_unlock_write(vma->anon_vma);
    khugepaged_enter_vma_merge(vma, vma->vm_flags);
    validate_mm(mm);
    + validate_mm_mt(mm);
    return error;
    }
    #endif /* CONFIG_STACK_GROWSUP || CONFIG_IA64 */
    @@ -2472,6 +2662,7 @@ int expand_downwards(struct vm_area_struct *vma,
    struct vm_area_struct *prev;
    int error = 0;

    + validate_mm(mm);
    address &= PAGE_MASK;
    if (address < mmap_min_addr)
    return -EPERM;
    @@ -2525,6 +2716,8 @@ int expand_downwards(struct vm_area_struct *vma,
    anon_vma_interval_tree_pre_update_vma(vma);
    vma->vm_start = address;
    vma->vm_pgoff -= grow;
    + /* Overwrite old entry in mtree. */
    + vma_mt_store(mm, vma);
    anon_vma_interval_tree_post_update_vma(vma);
    vma_gap_update(vma);
    spin_unlock(&mm->page_table_lock);
    @@ -2666,6 +2859,7 @@ detach_vmas_to_be_unmapped(struct mm_struct *mm, struct vm_area_struct *vma,

    insertion_point = (prev ? &prev->vm_next : &mm->mmap);
    vma->vm_prev = NULL;
    + vma_mt_szero(mm, vma->vm_start, end);
    do {
    vma_rb_erase(vma, &mm->mm_rb);
    mm->map_count--;
    @@ -2704,6 +2898,7 @@ 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);
    @@ -2756,6 +2951,7 @@ 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;
    }

    @@ -3027,6 +3223,7 @@ static int do_brk_flags(unsigned long addr, unsigned long len, unsigned long fla
    pgoff_t pgoff = addr >> PAGE_SHIFT;
    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)
    @@ -3084,6 +3281,7 @@ static int do_brk_flags(unsigned long addr, unsigned long len, unsigned long fla
    if (flags & VM_LOCKED)
    mm->locked_vm += (len >> PAGE_SHIFT);
    vma->vm_flags |= VM_SOFTDIRTY;
    + validate_mm_mt(mm);
    return 0;
    }

    @@ -3182,6 +3380,9 @@ void exit_mmap(struct mm_struct *mm)
    vma = remove_vma(vma);
    cond_resched();
    }
    +
    + trace_exit_mmap(mm);
    + mtree_destroy(&mm->mm_mt);
    vm_unacct_memory(nr_accounted);
    }

    @@ -3193,10 +3394,25 @@ int insert_vm_struct(struct mm_struct *mm, struct vm_area_struct *vma)
    {
    struct vm_area_struct *prev;
    struct rb_node **rb_link, *rb_parent;
    + unsigned long start = vma->vm_start;
    + struct vm_area_struct *overlap = NULL;

    if (find_vma_links(mm, vma->vm_start, vma->vm_end,
    &prev, &rb_link, &rb_parent))
    return -ENOMEM;
    +
    + overlap = mt_find(&mm->mm_mt, &start, vma->vm_end - 1);
    + if (overlap) {
    +
    + pr_err("Found vma ending at %lu\n", start - 1);
    + pr_err("vma : %lu => %lu-%lu\n", (unsigned long)overlap,
    + overlap->vm_start, overlap->vm_end - 1);
    +#if defined(CONFIG_DEBUG_MAPLE_TREE)
    + mt_dump(&mm->mm_mt);
    +#endif
    + BUG();
    + }
    +
    if ((vma->vm_flags & VM_ACCOUNT) &&
    security_vm_enough_memory_mm(mm, vma_pages(vma)))
    return -ENOMEM;
    @@ -3236,7 +3452,9 @@ struct vm_area_struct *copy_vma(struct vm_area_struct **vmap,
    struct vm_area_struct *new_vma, *prev;
    struct rb_node **rb_link, *rb_parent;
    bool faulted_in_anon_vma = true;
    + unsigned long index = addr;

    + 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.
    @@ -3248,6 +3466,8 @@ struct vm_area_struct *copy_vma(struct vm_area_struct **vmap,

    if (find_vma_links(mm, addr, addr + len, &prev, &rb_link, &rb_parent))
    return NULL; /* should never get here */
    + if (mt_find(&mm->mm_mt, &index, addr+len - 1))
    + BUG();
    new_vma = vma_merge(mm, prev, addr, addr + len, vma->vm_flags,
    vma->anon_vma, vma->vm_file, pgoff, vma_policy(vma),
    vma->vm_userfaultfd_ctx);
    @@ -3291,6 +3511,7 @@ struct vm_area_struct *copy_vma(struct vm_area_struct **vmap,
    vma_link(mm, new_vma, prev, rb_link, rb_parent);
    *need_rmap_locks = false;
    }
    + validate_mm_mt(mm);
    return new_vma;

    out_free_mempol:
    @@ -3298,6 +3519,7 @@ 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;
    }

    @@ -3434,6 +3656,7 @@ 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);
    @@ -3455,10 +3678,12 @@ 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);
    }

    --
    2.30.2
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      Last update: 2021-10-05 03:32    [W:4.194 / U:0.036 seconds]
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