From: "Liam R. Howlett" <Liam.Howlett@xxxxxxxxxx> 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. 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. This also moves the mmap_lock() in exit_mmap() since the oom reaper call does walk the VMAs. Otherwise lockdep will be unhappy if oom happens. Link: https://lkml.kernel.org/r/20220504010716.661115-10-Liam.Howlett@xxxxxxxxxx Signed-off-by: Liam R. Howlett <Liam.Howlett@xxxxxxxxxx> Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx> Cc: Catalin Marinas <catalin.marinas@xxxxxxx> Cc: David Howells <dhowells@xxxxxxxxxx> Cc: SeongJae Park <sj@xxxxxxxxxx> Cc: Vlastimil Babka <vbabka@xxxxxxx> Cc: Will Deacon <will@xxxxxxxxxx> Cc: Davidlohr Bueso <dave@xxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- arch/x86/kernel/tboot.c | 1 + drivers/firmware/efi/efi.c | 1 + include/linux/mm.h | 5 + include/linux/mm_types.h | 3 + include/trace/events/mmap.h | 73 ++++++++ kernel/fork.c | 20 ++- mm/init-mm.c | 2 + mm/mmap.c | 320 +++++++++++++++++++++++++++++++++--- mm/nommu.c | 13 ++ 9 files changed, 412 insertions(+), 26 deletions(-) diff --git a/arch/x86/kernel/tboot.c b/arch/x86/kernel/tboot.c index 0c1154a1c403..71c54ad3868a 100644 --- a/arch/x86/kernel/tboot.c +++ b/arch/x86/kernel/tboot.c @@ -97,6 +97,7 @@ 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_EXT(mm_mt, MM_MT_FLAGS, tboot_mm.mmap_lock), .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 860534bcfdac..1eddef189d68 100644 --- a/drivers/firmware/efi/efi.c +++ b/drivers/firmware/efi/efi.c @@ -58,6 +58,7 @@ static unsigned long __initdata rt_prop = EFI_INVALID_TABLE_ADDR; struct mm_struct efi_mm = { .mm_rb = RB_ROOT, + .mm_mt = MTREE_INIT_EXT(mm_mt, MM_MT_FLAGS, efi_mm.mmap_lock), .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 bc8f326be0ce..810b3dd929e4 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -2581,6 +2581,8 @@ 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); +/* mmap.c */ +void vma_mas_store(struct vm_area_struct *vma, struct ma_state *mas); /* interval_tree.c */ void vma_interval_tree_insert(struct vm_area_struct *node, @@ -2644,6 +2646,9 @@ extern struct vm_area_struct *copy_vma(struct vm_area_struct **, bool *need_rmap_locks); extern void exit_mmap(struct mm_struct *); +void vma_mas_store(struct vm_area_struct *vma, struct ma_state *mas); +void vma_mas_remove(struct vm_area_struct *vma, struct ma_state *mas); + static inline int check_data_rlimit(unsigned long rlim, unsigned long new, unsigned long start, diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h index c29ab4c0cd5c..254c30def2b2 100644 --- a/include/linux/mm_types.h +++ b/include/linux/mm_types.h @@ -9,6 +9,7 @@ #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> @@ -481,6 +482,7 @@ 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 @@ -676,6 +678,7 @@ struct mm_struct { unsigned long cpu_bitmap[]; }; +#define MM_MT_FLAGS (MT_FLAGS_ALLOC_RANGE | MT_FLAGS_LOCK_EXTERN) extern struct mm_struct init_mm; /* Pointer magic because the dynamic array size confuses some compilers. */ diff --git a/include/trace/events/mmap.h b/include/trace/events/mmap.h index 4661f7ba07c0..216de5f03621 100644 --- a/include/trace/events/mmap.h +++ b/include/trace/events/mmap.h @@ -42,6 +42,79 @@ TRACE_EVENT(vm_unmapped_area, __entry->low_limit, __entry->high_limit, __entry->align_mask, __entry->align_offset) ); + +TRACE_EVENT(vma_mas_szero, + TP_PROTO(struct maple_tree *mt, unsigned long start, + unsigned long end), + + TP_ARGS(mt, start, end), + + TP_STRUCT__entry( + __field(struct maple_tree *, mt) + __field(unsigned long, start) + __field(unsigned long, end) + ), + + TP_fast_assign( + __entry->mt = mt; + __entry->start = start; + __entry->end = end; + ), + + TP_printk("mt_mod %p, (NULL), SNULL, %lu, %lu,", + __entry->mt, + (unsigned long) __entry->start, + (unsigned long) __entry->end + ) +); + +TRACE_EVENT(vma_store, + TP_PROTO(struct maple_tree *mt, struct vm_area_struct *vma), + + TP_ARGS(mt, vma), + + TP_STRUCT__entry( + __field(struct maple_tree *, mt) + __field(struct vm_area_struct *, vma) + __field(unsigned long, vm_start) + __field(unsigned long, vm_end) + ), + + TP_fast_assign( + __entry->mt = mt; + __entry->vma = vma; + __entry->vm_start = vma->vm_start; + __entry->vm_end = vma->vm_end - 1; + ), + + TP_printk("mt_mod %p, (%p), STORE, %lu, %lu,", + __entry->mt, __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) + __field(struct maple_tree *, mt) + ), + + TP_fast_assign( + __entry->mm = mm; + __entry->mt = &mm->mm_mt; + ), + + TP_printk("mt_mod %p, DESTROY\n", + __entry->mt + ) +); + #endif /* This part must be outside protection */ diff --git a/kernel/fork.c b/kernel/fork.c index 9d44f2d46c69..1840da0732f6 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -585,6 +585,7 @@ static __latent_entropy int dup_mmap(struct mm_struct *mm, int retval; unsigned long charge; LIST_HEAD(uf); + MA_STATE(mas, &mm->mm_mt, 0, 0); uprobe_start_dup_mmap(); if (mmap_write_lock_killable(oldmm)) { @@ -614,6 +615,10 @@ static __latent_entropy int dup_mmap(struct mm_struct *mm, goto out; khugepaged_fork(mm, oldmm); + retval = mas_expected_entries(&mas, oldmm->map_count); + if (retval) + goto out; + prev = NULL; for (mpnt = oldmm->mmap; mpnt; mpnt = mpnt->vm_next) { struct file *file; @@ -629,7 +634,7 @@ static __latent_entropy int dup_mmap(struct mm_struct *mm, */ if (fatal_signal_pending(current)) { retval = -EINTR; - goto out; + goto loop_out; } if (mpnt->vm_flags & VM_ACCOUNT) { unsigned long len = vma_pages(mpnt); @@ -694,6 +699,11 @@ 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 */ + mas.index = tmp->vm_start; + mas.last = tmp->vm_end - 1; + mas_store(&mas, tmp); + mm->map_count++; if (!(tmp->vm_flags & VM_WIPEONFORK)) retval = copy_page_range(tmp, mpnt); @@ -702,10 +712,12 @@ static __latent_entropy int dup_mmap(struct mm_struct *mm, tmp->vm_ops->open(tmp); if (retval) - goto out; + goto loop_out; } /* a new mm has just been created */ retval = arch_dup_mmap(oldmm, mm); +loop_out: + mas_destroy(&mas); out: mmap_write_unlock(mm); flush_tlb_mm(oldmm); @@ -721,7 +733,7 @@ static __latent_entropy int dup_mmap(struct mm_struct *mm, fail_nomem: retval = -ENOMEM; vm_unacct_memory(charge); - goto out; + goto loop_out; } static inline int mm_alloc_pgd(struct mm_struct *mm) @@ -1111,6 +1123,8 @@ 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, MM_MT_FLAGS); + mt_set_external_lock(&mm->mm_mt, &mm->mmap_lock); 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 fbe7844d0912..b912b0f2eced 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> @@ -29,6 +30,7 @@ */ struct mm_struct init_mm = { .mm_rb = RB_ROOT, + .mm_mt = MTREE_INIT_EXT(mm_mt, MM_MT_FLAGS, init_mm.mmap_lock), .pgd = swapper_pg_dir, .mm_users = ATOMIC_INIT(2), .mm_count = ATOMIC_INIT(1), diff --git a/mm/mmap.c b/mm/mmap.c index 61e6135c54ef..9c75bd3b78ba 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -381,7 +381,70 @@ static int browse_rb(struct mm_struct *mm) } return bug ? -1 : i; } +#if defined(CONFIG_DEBUG_VM_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); + 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); + 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; @@ -436,6 +499,7 @@ 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 @@ -680,6 +744,56 @@ static void __vma_link_file(struct vm_area_struct *vma) } } +/* + * 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. + */ +void vma_mas_store(struct vm_area_struct *vma, struct ma_state *mas) +{ + trace_vma_store(mas->tree, vma); + mas_set_range(mas, vma->vm_start, vma->vm_end - 1); + mas_store_prealloc(mas, vma); +} + +/* + * 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. + */ +void vma_mas_remove(struct vm_area_struct *vma, struct ma_state *mas) +{ + trace_vma_mas_szero(mas->tree, vma->vm_start, vma->vm_end - 1); + mas->index = vma->vm_start; + mas->last = vma->vm_end - 1; + mas_store_prealloc(mas, NULL); +} + +/* + * vma_mas_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. + */ +static inline void vma_mas_szero(struct ma_state *mas, unsigned long start, + unsigned long end) +{ + trace_vma_mas_szero(mas->tree, start, end - 1); + mas_set_range(mas, start, end - 1); + mas_store_prealloc(mas, NULL); +} + static void __vma_link(struct mm_struct *mm, struct vm_area_struct *vma, struct vm_area_struct *prev, struct rb_node **rb_link, @@ -689,17 +803,22 @@ __vma_link(struct mm_struct *mm, struct vm_area_struct *vma, __vma_link_rb(mm, vma, rb_link, rb_parent); } -static void vma_link(struct mm_struct *mm, struct vm_area_struct *vma, +static int 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) { + MA_STATE(mas, &mm->mm_mt, 0, 0); struct address_space *mapping = NULL; + if (mas_preallocate(&mas, vma, GFP_KERNEL)) + return -ENOMEM; + if (vma->vm_file) { mapping = vma->vm_file->f_mapping; i_mmap_lock_write(mapping); } + vma_mas_store(vma, &mas); __vma_link(mm, vma, prev, rb_link, rb_parent); __vma_link_file(vma); @@ -708,13 +827,15 @@ static void vma_link(struct mm_struct *mm, struct vm_area_struct *vma, mm->map_count++; validate_mm(mm); + return 0; } /* * Helper for vma_adjust() in the split_vma insert case: insert a vma into the * mm's list and rbtree. It has already been inserted into the interval tree. */ -static void __insert_vm_struct(struct mm_struct *mm, struct vm_area_struct *vma) +static void __insert_vm_struct(struct mm_struct *mm, struct ma_state *mas, + struct vm_area_struct *vma) { struct vm_area_struct *prev; struct rb_node **rb_link, *rb_parent; @@ -722,7 +843,10 @@ static void __insert_vm_struct(struct mm_struct *mm, struct vm_area_struct *vma) if (find_vma_links(mm, vma->vm_start, vma->vm_end, &prev, &rb_link, &rb_parent)) BUG(); - __vma_link(mm, vma, prev, rb_link, rb_parent); + + vma_mas_store(vma, mas); + __vma_link_list(mm, vma, prev); + __vma_link_rb(mm, vma, rb_link, rb_parent); mm->map_count++; } @@ -756,10 +880,13 @@ int __vma_adjust(struct vm_area_struct *vma, unsigned long start, bool start_changed = false, end_changed = false; long adjust_next = 0; int remove_next = 0; + MA_STATE(mas, &mm->mm_mt, 0, 0); + struct vm_area_struct *exporter = NULL, *importer = NULL; - if (next && !insert) { - struct vm_area_struct *exporter = NULL, *importer = NULL; + validate_mm(mm); + validate_mm_mt(mm); + if (next && !insert) { if (end >= next->vm_end) { /* * vma expands, overlapping all the next, and @@ -842,6 +969,12 @@ int __vma_adjust(struct vm_area_struct *vma, unsigned long start, again: vma_adjust_trans_huge(orig_vma, start, end, adjust_next); + if (mas_preallocate(&mas, vma, GFP_KERNEL)) { + if (exporter && exporter->anon_vma) + unlink_anon_vmas(importer); + return -ENOMEM; + } + if (file) { mapping = file->f_mapping; root = &mapping->i_mmap; @@ -882,17 +1015,28 @@ 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_mas_szero(&mas, 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_mas_szero(&mas, end, old_end); end_changed = true; } + + if (end_changed || start_changed) + vma_mas_store(vma, &mas); + vma->vm_pgoff = pgoff; if (adjust_next) { next->vm_start += adjust_next; next->vm_pgoff += adjust_next >> PAGE_SHIFT; + vma_mas_store(next, &mas); } if (file) { @@ -906,6 +1050,8 @@ 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); @@ -928,7 +1074,7 @@ int __vma_adjust(struct vm_area_struct *vma, unsigned long start, * us to insert it before dropping the locks * (it may either follow vma or precede it). */ - __insert_vm_struct(mm, insert); + __insert_vm_struct(mm, &mas, insert); } else { if (start_changed) vma_gap_update(vma); @@ -1025,6 +1171,7 @@ int __vma_adjust(struct vm_area_struct *vma, unsigned long start, uprobe_mmap(insert); validate_mm(mm); + validate_mm_mt(mm); return 0; } @@ -1178,6 +1325,7 @@ 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. @@ -1253,6 +1401,7 @@ struct vm_area_struct *vma_merge(struct mm_struct *mm, khugepaged_enter_vma(area, vm_flags); return area; } + validate_mm_mt(mm); return NULL; } @@ -1732,6 +1881,7 @@ 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; @@ -1846,7 +1996,13 @@ unsigned long mmap_region(struct file *file, unsigned long addr, goto free_vma; } - vma_link(mm, vma, prev, rb_link, rb_parent); + if (vma_link(mm, vma, prev, rb_link, rb_parent)) { + error = -ENOMEM; + if (file) + goto unmap_and_free_vma; + else + goto free_vma; + } /* * vma_merge() calls khugepaged_enter_vma() either, the below @@ -1886,6 +2042,7 @@ 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: @@ -1902,6 +2059,7 @@ unsigned long mmap_region(struct file *file, unsigned long addr, unacct_error: if (charged) vm_unacct_memory(charged); + validate_mm_mt(mm); return error; } @@ -1918,12 +2076,19 @@ 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; + mas_empty_area(&mas, info->low_limit, info->high_limit - 1, + length); + 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; @@ -2005,20 +2170,31 @@ 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 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; + mas_empty_area_rev(&mas, info->low_limit, info->high_limit - 1, + length); + gap = mas.last + 1 - info->length; + gap -= (gap - info->align_offset) & info->align_mask; + /* * Adjust search limits by the desired length. * See implementation comment at top of unmapped_area(). @@ -2104,6 +2280,32 @@ 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_VM_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; } @@ -2326,7 +2528,6 @@ struct vm_area_struct *find_vma(struct mm_struct *mm, unsigned long addr) vmacache_update(addr, vma); return vma; } - EXPORT_SYMBOL(find_vma); /* @@ -2399,7 +2600,9 @@ int expand_upwards(struct vm_area_struct *vma, unsigned long address) struct vm_area_struct *next; unsigned long gap_addr; int error = 0; + MA_STATE(mas, &mm->mm_mt, 0, 0); + validate_mm_mt(mm); if (!(vma->vm_flags & VM_GROWSUP)) return -EFAULT; @@ -2423,9 +2626,14 @@ int expand_upwards(struct vm_area_struct *vma, unsigned long address) /* Check that both stack segments have the same anon_vma? */ } + if (mas_preallocate(&mas, vma, GFP_KERNEL)) + return -ENOMEM; + /* We must make sure the anon_vma is allocated. */ - if (unlikely(anon_vma_prepare(vma))) + if (unlikely(anon_vma_prepare(vma))) { + mas_destroy(&mas); return -ENOMEM; + } /* * vma->vm_start/vm_end cannot change under us because the caller @@ -2462,6 +2670,8 @@ int expand_upwards(struct vm_area_struct *vma, unsigned long address) vm_stat_account(mm, vma->vm_flags, grow); anon_vma_interval_tree_pre_update_vma(vma); vma->vm_end = address; + /* Overwrite old entry in mtree. */ + vma_mas_store(vma, &mas); anon_vma_interval_tree_post_update_vma(vma); if (vma->vm_next) vma_gap_update(vma->vm_next); @@ -2476,6 +2686,8 @@ int expand_upwards(struct vm_area_struct *vma, unsigned long address) anon_vma_unlock_write(vma->anon_vma); khugepaged_enter_vma(vma, vma->vm_flags); validate_mm(mm); + validate_mm_mt(mm); + mas_destroy(&mas); return error; } #endif /* CONFIG_STACK_GROWSUP || CONFIG_IA64 */ @@ -2489,7 +2701,9 @@ int expand_downwards(struct vm_area_struct *vma, struct mm_struct *mm = vma->vm_mm; struct vm_area_struct *prev; int error = 0; + MA_STATE(mas, &mm->mm_mt, 0, 0); + validate_mm(mm); address &= PAGE_MASK; if (address < mmap_min_addr) return -EPERM; @@ -2503,9 +2717,14 @@ int expand_downwards(struct vm_area_struct *vma, return -ENOMEM; } + if (mas_preallocate(&mas, vma, GFP_KERNEL)) + return -ENOMEM; + /* We must make sure the anon_vma is allocated. */ - if (unlikely(anon_vma_prepare(vma))) + if (unlikely(anon_vma_prepare(vma))) { + mas_destroy(&mas); return -ENOMEM; + } /* * vma->vm_start/vm_end cannot change under us because the caller @@ -2543,6 +2762,8 @@ 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_mas_store(vma, &mas); anon_vma_interval_tree_post_update_vma(vma); vma_gap_update(vma); spin_unlock(&mm->page_table_lock); @@ -2554,6 +2775,7 @@ int expand_downwards(struct vm_area_struct *vma, anon_vma_unlock_write(vma->anon_vma); khugepaged_enter_vma(vma, vma->vm_flags); validate_mm(mm); + mas_destroy(&mas); return error; } @@ -2676,14 +2898,17 @@ static void unmap_region(struct mm_struct *mm, * vma list as we go.. */ static bool -detach_vmas_to_be_unmapped(struct mm_struct *mm, struct vm_area_struct *vma, - struct vm_area_struct *prev, unsigned long end) +detach_vmas_to_be_unmapped(struct mm_struct *mm, struct ma_state *mas, + struct vm_area_struct *vma, struct vm_area_struct *prev, + unsigned long end) { struct vm_area_struct **insertion_point; struct vm_area_struct *tail_vma = NULL; insertion_point = (prev ? &prev->vm_next : &mm->mmap); vma->vm_prev = NULL; + mas_set_range(mas, vma->vm_start, end - 1); + mas_store_prealloc(mas, NULL); do { vma_rb_erase(vma, &mm->mm_rb); if (vma->vm_flags & VM_LOCKED) @@ -2724,6 +2949,7 @@ 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); @@ -2776,6 +3002,7 @@ 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; } @@ -2802,6 +3029,8 @@ int __do_munmap(struct mm_struct *mm, unsigned long start, size_t len, { unsigned long end; struct vm_area_struct *vma, *prev, *last; + int error = -ENOMEM; + MA_STATE(mas, &mm->mm_mt, 0, 0); if ((offset_in_page(start)) || start > TASK_SIZE || len > TASK_SIZE-start) return -EINVAL; @@ -2822,6 +3051,9 @@ int __do_munmap(struct mm_struct *mm, unsigned long start, size_t len, vma = find_vma_intersection(mm, start, end); if (!vma) return 0; + + if (mas_preallocate(&mas, vma, GFP_KERNEL)) + return -ENOMEM; prev = vma->vm_prev; /* @@ -2832,7 +3064,6 @@ int __do_munmap(struct mm_struct *mm, unsigned long start, size_t len, * places tmp vma above, and higher split_vma places tmp vma below. */ if (start > vma->vm_start) { - int error; /* * Make sure that map_count on return from munmap() will @@ -2840,20 +3071,20 @@ int __do_munmap(struct mm_struct *mm, unsigned long start, size_t len, * its limit temporarily, to help free resources as expected. */ if (end < vma->vm_end && mm->map_count >= sysctl_max_map_count) - return -ENOMEM; + goto map_count_exceeded; error = __split_vma(mm, vma, start, 0); if (error) - return error; + goto split_failed; prev = vma; } /* Does it split the last one? */ last = find_vma(mm, end); if (last && end > last->vm_start) { - int error = __split_vma(mm, last, end, 1); + error = __split_vma(mm, last, end, 1); if (error) - return error; + goto split_failed; } vma = vma_next(mm, prev); @@ -2867,13 +3098,13 @@ int __do_munmap(struct mm_struct *mm, unsigned long start, size_t len, * split, despite we could. This is unlikely enough * failure that it's not worth optimizing it for. */ - int error = userfaultfd_unmap_prep(vma, start, end, uf); + error = userfaultfd_unmap_prep(vma, start, end, uf); if (error) - return error; + goto userfaultfd_error; } /* Detach vmas from rbtree */ - if (!detach_vmas_to_be_unmapped(mm, vma, prev, end)) + if (!detach_vmas_to_be_unmapped(mm, &mas, vma, prev, end)) downgrade = false; if (downgrade) @@ -2885,6 +3116,12 @@ int __do_munmap(struct mm_struct *mm, unsigned long start, size_t len, remove_vma_list(mm, vma); return downgrade ? 1 : 0; + +map_count_exceeded: +split_failed: +userfaultfd_error: + mas_destroy(&mas); + return error; } int do_munmap(struct mm_struct *mm, unsigned long start, size_t len, @@ -3024,6 +3261,7 @@ 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) @@ -3073,7 +3311,9 @@ static int do_brk_flags(unsigned long addr, unsigned long len, unsigned long fla vma->vm_pgoff = pgoff; vma->vm_flags = flags; vma->vm_page_prot = vm_get_page_prot(flags); - vma_link(mm, vma, prev, rb_link, rb_parent); + if(vma_link(mm, vma, prev, rb_link, rb_parent)) + goto no_vma_link; + out: perf_event_mmap(vma); mm->total_vm += len >> PAGE_SHIFT; @@ -3081,7 +3321,12 @@ 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; + +no_vma_link: + vm_area_free(vma); + return -ENOMEM; } int vm_brk_flags(unsigned long addr, unsigned long request, unsigned long flags) @@ -3170,6 +3415,9 @@ void exit_mmap(struct mm_struct *mm) vma = remove_vma(vma); cond_resched(); } + + trace_exit_mmap(mm); + __mt_destroy(&mm->mm_mt); mm->mmap = NULL; mmap_write_unlock(mm); vm_unacct_memory(nr_accounted); @@ -3183,10 +3431,25 @@ 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_VM_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; @@ -3208,7 +3471,9 @@ 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, rb_link, rb_parent); + if (vma_link(mm, vma, prev, rb_link, rb_parent)) + return -ENOMEM; + return 0; } @@ -3226,7 +3491,9 @@ 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. @@ -3238,6 +3505,8 @@ 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, anon_vma_name(vma)); @@ -3281,6 +3550,7 @@ 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: @@ -3288,6 +3558,7 @@ 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; } @@ -3424,6 +3695,7 @@ 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); @@ -3446,10 +3718,12 @@ 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); } diff --git a/mm/nommu.c b/mm/nommu.c index 9d7afc2d959e..5af0b050eba8 100644 --- a/mm/nommu.c +++ b/mm/nommu.c @@ -545,6 +545,19 @@ static void put_nommu_region(struct vm_region *region) __put_nommu_region(region); } +void vma_mas_store(struct vm_area_struct *vma, struct ma_state *mas) +{ + mas_set_range(mas, vma->vm_start, vma->vm_end - 1); + mas_store_prealloc(mas, vma); +} + +void vma_mas_remove(struct vm_area_struct *vma, struct ma_state *mas) +{ + mas->index = vma->vm_start; + mas->last = vma->vm_end - 1; + mas_store_prealloc(mas, NULL); +} + /* * add a VMA into a process's mm_struct in the appropriate place in the list * and tree and add to the address space's page tree also if not an anonymous -- 2.35.1
