From: "Liam R. Howlett" <Liam.Howlett@xxxxxxxxxx> Remove the RB tree and start using the maple tree for vm_area_struct tracking. Drop validate_mm() calls in expand_upwards() and expand_downwards() as the lock is not held. Signed-off-by: Liam R. Howlett <Liam.Howlett@xxxxxxxxxx> --- arch/x86/kernel/tboot.c | 1 - drivers/firmware/efi/efi.c | 1 - include/linux/mm.h | 2 - include/linux/mm_types.h | 14 -- kernel/fork.c | 8 - mm/init-mm.c | 2 - mm/mmap.c | 496 ++++++++----------------------------- mm/nommu.c | 88 ++----- mm/util.c | 8 + 9 files changed, 136 insertions(+), 484 deletions(-) diff --git a/arch/x86/kernel/tboot.c b/arch/x86/kernel/tboot.c index 859e8d2ea070..a8e3130890ea 100644 --- a/arch/x86/kernel/tboot.c +++ b/arch/x86/kernel/tboot.c @@ -97,7 +97,6 @@ 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), diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c index 0b40291416ca..a1efb231cee9 100644 --- a/drivers/firmware/efi/efi.c +++ b/drivers/firmware/efi/efi.c @@ -54,7 +54,6 @@ static unsigned long __initdata mem_reserve = EFI_INVALID_TABLE_ADDR; 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), diff --git a/include/linux/mm.h b/include/linux/mm.h index c28bd97a4ecd..784f8fec3b65 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -2692,8 +2692,6 @@ extern int __split_vma(struct mm_struct *, struct vm_area_struct *, extern int split_vma(struct mm_struct *, struct vm_area_struct *, unsigned long addr, int new_below); extern int insert_vm_struct(struct mm_struct *, struct vm_area_struct *); -extern void __vma_link_rb(struct mm_struct *, struct vm_area_struct *, - struct rb_node **, struct rb_node *); extern void unlink_file_vma(struct vm_area_struct *); extern struct vm_area_struct *copy_vma(struct vm_area_struct **, unsigned long addr, unsigned long len, pgoff_t pgoff, diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h index b0c3494011bb..04b055a80501 100644 --- a/include/linux/mm_types.h +++ b/include/linux/mm_types.h @@ -402,19 +402,6 @@ struct vm_area_struct { /* linked list of VM areas per task, sorted by address */ struct vm_area_struct *vm_next, *vm_prev; - - struct rb_node vm_rb; - - /* - * Largest free memory gap in bytes to the left of this VMA. - * Either between this VMA and vma->vm_prev, or between one of the - * VMAs below us in the VMA rbtree and its ->vm_prev. This helps - * get_unmapped_area find a free area of the right size. - */ - unsigned long rb_subtree_gap; - - /* Second cache line starts here. */ - struct mm_struct *vm_mm; /* The address space we belong to. */ /* @@ -469,7 +456,6 @@ 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 unsigned long (*get_unmapped_area) (struct file *filp, diff --git a/kernel/fork.c b/kernel/fork.c index c9f8465d8ae2..dcc58063f632 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -499,7 +499,6 @@ static __latent_entropy int dup_mmap(struct mm_struct *mm, struct mm_struct *oldmm) { struct vm_area_struct *mpnt, *tmp, *prev, **pprev; - struct rb_node **rb_link, *rb_parent; int retval; unsigned long charge = 0; MA_STATE(old_mas, &oldmm->mm_mt, 0, 0); @@ -526,8 +525,6 @@ static __latent_entropy int dup_mmap(struct mm_struct *mm, mm->exec_vm = oldmm->exec_vm; mm->stack_vm = oldmm->stack_vm; - rb_link = &mm->mm_rb.rb_node; - rb_parent = NULL; pprev = &mm->mmap; retval = ksm_fork(mm, oldmm); if (retval) @@ -617,10 +614,6 @@ static __latent_entropy int dup_mmap(struct mm_struct *mm, tmp->vm_prev = prev; prev = tmp; - __vma_link_rb(mm, tmp, rb_link, rb_parent); - 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; @@ -1061,7 +1054,6 @@ static struct mm_struct *mm_init(struct mm_struct *mm, struct task_struct *p, struct user_namespace *user_ns) { 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; diff --git a/mm/init-mm.c b/mm/init-mm.c index 7622ca24eeb7..faf70cda302f 100644 --- a/mm/init-mm.c +++ b/mm/init-mm.c @@ -1,6 +1,5 @@ // 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> @@ -28,7 +27,6 @@ * and size this cpu_bitmask to NR_CPUS. */ 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), diff --git a/mm/mmap.c b/mm/mmap.c index 0ee4e430e4b1..93ed19b2c6ce 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -38,7 +38,6 @@ #include <linux/audit.h> #include <linux/khugepaged.h> #include <linux/uprobes.h> -#include <linux/rbtree_augmented.h> #include <linux/notifier.h> #include <linux/memory.h> #include <linux/printk.h> @@ -288,93 +287,6 @@ SYSCALL_DEFINE1(brk, unsigned long, brk) return origbrk; } -static inline unsigned long vma_compute_gap(struct vm_area_struct *vma) -{ - unsigned long gap, prev_end; - - /* - * Note: in the rare case of a VM_GROWSDOWN above a VM_GROWSUP, we - * allow two stack_guard_gaps between them here, and when choosing - * an unmapped area; whereas when expanding we only require one. - * That's a little inconsistent, but keeps the code here simpler. - */ - gap = vm_start_gap(vma); - if (vma->vm_prev) { - prev_end = vm_end_gap(vma->vm_prev); - if (gap > prev_end) - gap -= prev_end; - else - gap = 0; - } - return gap; -} - -#ifdef CONFIG_DEBUG_VM_RB -static unsigned long vma_compute_subtree_gap(struct vm_area_struct *vma) -{ - unsigned long max = vma_compute_gap(vma), subtree_gap; - if (vma->vm_rb.rb_left) { - subtree_gap = rb_entry(vma->vm_rb.rb_left, - struct vm_area_struct, vm_rb)->rb_subtree_gap; - if (subtree_gap > max) - max = subtree_gap; - } - if (vma->vm_rb.rb_right) { - subtree_gap = rb_entry(vma->vm_rb.rb_right, - struct vm_area_struct, vm_rb)->rb_subtree_gap; - if (subtree_gap > max) - max = subtree_gap; - } - return max; -} - -static int browse_rb(struct mm_struct *mm) -{ - struct rb_root *root = &mm->mm_rb; - int i = 0, j, bug = 0; - struct rb_node *nd, *pn = NULL; - unsigned long prev = 0, pend = 0; - - for (nd = rb_first(root); nd; nd = rb_next(nd)) { - struct vm_area_struct *vma; - vma = rb_entry(nd, struct vm_area_struct, vm_rb); - if (vma->vm_start < prev) { - pr_emerg("vm_start %lx < prev %lx\n", - vma->vm_start, prev); - bug = 1; - } - if (vma->vm_start < pend) { - pr_emerg("vm_start %lx < pend %lx\n", - vma->vm_start, pend); - bug = 1; - } - if (vma->vm_start > vma->vm_end) { - pr_emerg("vm_start %lx > vm_end %lx\n", - vma->vm_start, vma->vm_end); - bug = 1; - } - spin_lock(&mm->page_table_lock); - if (vma->rb_subtree_gap != vma_compute_subtree_gap(vma)) { - pr_emerg("free gap %lx, correct %lx\n", - vma->rb_subtree_gap, - vma_compute_subtree_gap(vma)); - bug = 1; - } - spin_unlock(&mm->page_table_lock); - i++; - pn = nd; - prev = vma->vm_start; - pend = vma->vm_end; - } - j = 0; - for (nd = pn; nd; nd = rb_prev(nd)) - j++; - if (i != j) { - pr_emerg("backwards %d, forwards %d\n", j, i); - bug = 1; - } - 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); @@ -402,17 +314,25 @@ static void validate_mm_mt(struct mm_struct *mm) dump_stack(); #ifdef CONFIG_DEBUG_VM dump_vma(vma_mt); - pr_emerg("and next in rb\n"); + pr_emerg("and vm_next\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, + 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); - pr_emerg("rb->next = %px %lu - %lu\n", vma->vm_next, - vma->vm_next->vm_start, vma->vm_next->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) { @@ -436,21 +356,6 @@ static void validate_mm_mt(struct mm_struct *mm) 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; - - for (nd = rb_first(root); nd; nd = rb_next(nd)) { - struct vm_area_struct *vma; - vma = rb_entry(nd, struct vm_area_struct, vm_rb); - VM_BUG_ON_VMA(vma != ignore && - vma->rb_subtree_gap != vma_compute_subtree_gap(vma), - vma); - } -} static void validate_mm(struct mm_struct *mm) { @@ -459,7 +364,10 @@ static void validate_mm(struct mm_struct *mm) unsigned long highest_address = 0; struct vm_area_struct *vma = mm->mmap; + validate_mm_mt(mm); + while (vma) { +#ifdef CONFIG_DEBUG_VM_RB struct anon_vma *anon_vma = vma->anon_vma; struct anon_vma_chain *avc; @@ -469,6 +377,7 @@ static void validate_mm(struct mm_struct *mm) anon_vma_interval_tree_verify(avc); anon_vma_unlock_read(anon_vma); } +#endif highest_address = vm_end_gap(vma); vma = vma->vm_next; @@ -483,80 +392,13 @@ static void validate_mm(struct mm_struct *mm) mm->highest_vm_end, highest_address); bug = 1; } - i = browse_rb(mm); - if (i != mm->map_count) { - if (i != -1) - pr_emerg("map_count %d rb %d\n", mm->map_count, i); - bug = 1; - } VM_BUG_ON_MM(bug, mm); } -#else -#define validate_mm_rb(root, ignore) do { } while (0) + +#else // !CONFIG_DEBUG_MAPLE_TREE #define validate_mm_mt(root) do { } while (0) #define validate_mm(mm) do { } while (0) -#endif - -RB_DECLARE_CALLBACKS_MAX(static, vma_gap_callbacks, - struct vm_area_struct, vm_rb, - unsigned long, rb_subtree_gap, vma_compute_gap) - -/* - * Update augmented rbtree rb_subtree_gap values after vma->vm_start or - * vma->vm_prev->vm_end values changed, without modifying the vma's position - * in the rbtree. - */ -static void vma_gap_update(struct vm_area_struct *vma) -{ - /* - * As it turns out, RB_DECLARE_CALLBACKS_MAX() already created - * a callback function that does exactly what we want. - */ - vma_gap_callbacks_propagate(&vma->vm_rb, NULL); -} - -static inline void vma_rb_insert(struct vm_area_struct *vma, - struct rb_root *root) -{ - /* All rb_subtree_gap values must be consistent prior to insertion */ - validate_mm_rb(root, NULL); - - rb_insert_augmented(&vma->vm_rb, root, &vma_gap_callbacks); -} - -static void __vma_rb_erase(struct vm_area_struct *vma, struct rb_root *root) -{ - /* - * Note rb_erase_augmented is a fairly large inline function, - * so make sure we instantiate it only once with our desired - * augmented rbtree callbacks. - */ - rb_erase_augmented(&vma->vm_rb, root, &vma_gap_callbacks); -} - -static __always_inline void vma_rb_erase_ignore(struct vm_area_struct *vma, - struct rb_root *root, - struct vm_area_struct *ignore) -{ - /* - * All rb_subtree_gap values must be consistent prior to erase, - * with the possible exception of - * - * a. the "next" vma being erased if next->vm_start was reduced in - * __vma_adjust() -> __vma_unlink() - * b. the vma being erased in detach_vmas_to_be_unmapped() -> - * vma_rb_erase() - */ - validate_mm_rb(root, ignore); - - __vma_rb_erase(vma, root); -} - -static __always_inline void vma_rb_erase(struct vm_area_struct *vma, - struct rb_root *root) -{ - vma_rb_erase_ignore(vma, root, vma); -} +#endif // CONFIG_DEBUG_MAPLE_TREE /* * vma has some anon_vma assigned, and is already inserted on that @@ -590,39 +432,26 @@ anon_vma_interval_tree_post_update_vma(struct vm_area_struct *vma) anon_vma_interval_tree_insert(avc, &avc->anon_vma->rb_root); } -static int find_vma_links(struct mm_struct *mm, unsigned long addr, - unsigned long end, struct vm_area_struct **pprev, - struct rb_node ***rb_link, struct rb_node **rb_parent) +/* + * range_has_overlap() - Check the @start - @end range for overlapping VMAs and + * sets up a pointer to the previous VMA + * @mm: the mm struct + * @start: the start address of the range + * @end: the end address of the range + * @pprev: the pointer to the pointer of the previous VMA + * + * Returns: True if there is an overlapping VMA, false otherwise + */ +static inline +bool range_has_overlap(struct mm_struct *mm, unsigned long start, + unsigned long end, struct vm_area_struct **pprev) { - struct rb_node **__rb_link, *__rb_parent, *rb_prev; - - mmap_assert_locked(mm); - __rb_link = &mm->mm_rb.rb_node; - rb_prev = __rb_parent = NULL; - - while (*__rb_link) { - struct vm_area_struct *vma_tmp; - - __rb_parent = *__rb_link; - vma_tmp = rb_entry(__rb_parent, struct vm_area_struct, vm_rb); + struct vm_area_struct *existing; - if (vma_tmp->vm_end > addr) { - /* Fail if an existing vma overlaps the area */ - if (vma_tmp->vm_start < end) - return -ENOMEM; - __rb_link = &__rb_parent->rb_left; - } else { - rb_prev = __rb_parent; - __rb_link = &__rb_parent->rb_right; - } - } - - *pprev = NULL; - if (rb_prev) - *pprev = rb_entry(rb_prev, struct vm_area_struct, vm_rb); - *rb_link = __rb_link; - *rb_parent = __rb_parent; - return 0; + MA_STATE(mas, &mm->mm_mt, start, start); + existing = mas_find(&mas, end - 1); + *pprev = mas_prev(&mas, 0); + return existing ? true : false; } /* @@ -649,8 +478,6 @@ static inline struct vm_area_struct *__vma_next(struct mm_struct *mm, * @start: The start of the range. * @len: The length of the range. * @pprev: pointer to the pointer that will be set to previous vm_area_struct - * @rb_link: the rb_node - * @rb_parent: the parent rb_node * * Find all the vm_area_struct that overlap from @start to * @end and munmap them. Set @pprev to the previous vm_area_struct. @@ -659,14 +486,12 @@ static inline struct vm_area_struct *__vma_next(struct mm_struct *mm, */ static inline int munmap_vma_range(struct mm_struct *mm, unsigned long start, unsigned long len, - struct vm_area_struct **pprev, struct rb_node ***link, - struct rb_node **parent, struct list_head *uf) + struct vm_area_struct **pprev, struct list_head *uf) { - - while (find_vma_links(mm, start, start + len, pprev, link, parent)) + // Needs optimization. + while (range_has_overlap(mm, start, start + len, pprev)) if (do_munmap(mm, start, len, uf)) return -ENOMEM; - return 0; } @@ -687,30 +512,6 @@ static unsigned long count_vma_pages_range(struct mm_struct *mm, return nr_pages; } -void __vma_link_rb(struct mm_struct *mm, struct vm_area_struct *vma, - struct rb_node **rb_link, struct rb_node *rb_parent) -{ - /* Update tracking information for the gap following the new vma. */ - if (vma->vm_next) - vma_gap_update(vma->vm_next); - else - mm->highest_vm_end = vm_end_gap(vma); - - /* - * vma->vm_prev wasn't known when we followed the rbtree to find the - * correct insertion point for that vma. As a result, we could not - * update the vma vm_rb parents rb_subtree_gap values on the way down. - * So, we first insert the vma with a zero rb_subtree_gap value - * (to be consistent with what we did on the way down), and then - * immediately update the gap to the correct value. Finally we - * rebalance the rbtree after all augmented values have been set. - */ - rb_link_node(&vma->vm_rb, rb_parent, rb_link); - vma->rb_subtree_gap = 0; - vma_gap_update(vma); - vma_rb_insert(vma, &mm->mm_rb); -} - static void __vma_link_file(struct vm_area_struct *vma) { struct file *file; @@ -758,19 +559,8 @@ void vma_store(struct mm_struct *mm, struct vm_area_struct *vma) mas_store_gfp(&mas, vma, GFP_KERNEL); } -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_store(mm, vma); - __vma_link_list(mm, vma, prev); - __vma_link_rb(mm, vma, rb_link, rb_parent); -} - 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) + struct vm_area_struct *prev) { struct address_space *mapping = NULL; @@ -779,7 +569,8 @@ static void vma_link(struct mm_struct *mm, struct vm_area_struct *vma, i_mmap_lock_write(mapping); } - __vma_link(mm, vma, prev, rb_link, rb_parent); + vma_store(mm, vma); + __vma_link_list(mm, vma, prev); __vma_link_file(vma); if (mapping) @@ -791,30 +582,19 @@ static void vma_link(struct mm_struct *mm, struct vm_area_struct *vma, /* * 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. + * 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) { struct vm_area_struct *prev; - struct rb_node **rb_link, *rb_parent; + MA_STATE(mas, &mm->mm_mt, vma->vm_start, vma->vm_start); - 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); + prev = mas_prev(&mas, 0); + vma_store(mm, vma); + __vma_link_list(mm, vma, prev); mm->map_count++; } -static __always_inline void __vma_unlink(struct mm_struct *mm, - struct vm_area_struct *vma, - struct vm_area_struct *ignore) -{ - vma_rb_erase_ignore(vma, &mm->mm_rb, ignore); - __vma_unlink_list(mm, vma); - /* Kill the cache */ - vmacache_invalidate(mm); -} - /* * We cannot adjust vm_start, vm_end, vm_pgoff fields of a vma that * is already present in an i_mmap tree without adjusting the tree. @@ -832,13 +612,10 @@ int __vma_adjust(struct vm_area_struct *vma, unsigned long start, struct rb_root_cached *root = NULL; struct anon_vma *anon_vma = NULL; struct file *file = vma->vm_file; - bool start_changed = false, end_changed = false; + bool vma_changed = false; 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; @@ -964,21 +741,23 @@ int __vma_adjust(struct vm_area_struct *vma, unsigned long start, } if (start != vma->vm_start) { - unsigned long old_start = vma->vm_start; + if (vma->vm_start < start) + vma_mt_szero(mm, vma->vm_start, start); + else + vma_changed = true; 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; + if (vma->vm_end > end) + vma_mt_szero(mm, end, vma->vm_end); + else + vma_changed = true; vma->vm_end = end; - if (old_end > end) - vma_mt_szero(mm, end, old_end); - end_changed = true; + if (!next) + mm->highest_vm_end = vm_end_gap(vma); } - if (end_changed || start_changed) + if (vma_changed) vma_store(mm, vma); vma->vm_pgoff = pgoff; @@ -996,25 +775,9 @@ int __vma_adjust(struct vm_area_struct *vma, unsigned long start, } if (remove_next) { - /* - * 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); - else - /* - * vma is not before next if they've been - * swapped. - * - * pre-swap() next->vm_start was reduced so - * tell validate_mm_rb to ignore pre-swap() - * "next" (which is stored in post-swap() - * "vma"). - */ - __vma_unlink(mm, next, vma); + __vma_unlink_list(mm, next); + /* Kill the cache */ + vmacache_invalidate(mm); if (file) __remove_shared_vm_struct(next, file, mapping); } else if (insert) { @@ -1024,15 +787,6 @@ int __vma_adjust(struct vm_area_struct *vma, unsigned long start, * (it may either follow vma or precede it). */ __insert_vm_struct(mm, insert); - } else { - if (start_changed) - vma_gap_update(vma); - if (end_changed) { - if (!next) - mm->highest_vm_end = vm_end_gap(vma); - else if (!adjust_next) - vma_gap_update(next); - } } if (anon_vma) { @@ -1090,10 +844,7 @@ int __vma_adjust(struct vm_area_struct *vma, unsigned long start, remove_next = 1; end = next->vm_end; goto again; - } - else if (next) - vma_gap_update(next); - else { + } else if (!next) { /* * If remove_next == 2 we obviously can't * reach this path. @@ -1120,8 +871,6 @@ int __vma_adjust(struct vm_area_struct *vma, unsigned long start, uprobe_mmap(insert); validate_mm(mm); - validate_mm_mt(mm); - return 0; } @@ -1268,7 +1017,6 @@ 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. @@ -1344,7 +1092,6 @@ 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; } @@ -1514,6 +1261,7 @@ unsigned long do_mmap(struct file *file, unsigned long addr, vm_flags_t vm_flags; int pkey = 0; + validate_mm(mm); *populate = 0; if (!len) @@ -1823,10 +1571,8 @@ unsigned long mmap_region(struct file *file, unsigned long addr, struct mm_struct *mm = current->mm; struct vm_area_struct *vma, *prev, *merge; int error; - 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; @@ -1842,8 +1588,8 @@ unsigned long mmap_region(struct file *file, unsigned long addr, return -ENOMEM; } - /* Clear old maps, set up prev, rb_link, rb_parent, and uf */ - if (munmap_vma_range(mm, addr, len, &prev, &rb_link, &rb_parent, uf)) + /* Clear old maps, set up prev and uf */ + if (munmap_vma_range(mm, addr, len, &prev, uf)) return -ENOMEM; /* * Private writable mapping: check memory availability @@ -1941,7 +1687,7 @@ unsigned long mmap_region(struct file *file, unsigned long addr, goto free_vma; } - vma_link(mm, vma, prev, rb_link, rb_parent); + vma_link(mm, vma, prev); /* Once vma denies write, undo our temporary denial count */ unmap_writable: if (file && vm_flags & VM_SHARED) @@ -1974,7 +1720,6 @@ 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: @@ -1991,7 +1736,6 @@ unsigned long mmap_region(struct file *file, unsigned long addr, unacct_error: if (charged) vm_unacct_memory(charged); - validate_mm_mt(mm); return error; } @@ -2336,7 +2080,6 @@ 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; @@ -2383,15 +2126,13 @@ int expand_upwards(struct vm_area_struct *vma, unsigned long address) error = acct_stack_growth(vma, size, grow); if (!error) { /* - * vma_gap_update() doesn't support concurrent - * updates, but we only hold a shared mmap_lock - * lock here, so we need to protect against - * concurrent vma expansions. - * anon_vma_lock_write() doesn't help here, as - * we don't guarantee that all growable vmas - * in a mm share the same root anon vma. - * So, we reuse mm->page_table_lock to guard - * against concurrent vma expansions. + * We only hold a shared mmap_lock lock here, so + * we need to protect against concurrent vma + * expansions. anon_vma_lock_write() doesn't + * help here, as we don't guarantee that all + * growable vmas in a mm share the same root + * anon vma. So, we reuse mm->page_table_lock + * to guard against concurrent vma expansions. */ spin_lock(&mm->page_table_lock); if (vma->vm_flags & VM_LOCKED) @@ -2399,10 +2140,9 @@ 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; + vma_store(mm, vma); anon_vma_interval_tree_post_update_vma(vma); - if (vma->vm_next) - vma_gap_update(vma->vm_next); - else + if (!vma->vm_next) mm->highest_vm_end = vm_end_gap(vma); spin_unlock(&mm->page_table_lock); @@ -2412,8 +2152,6 @@ 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 */ @@ -2421,14 +2159,12 @@ int expand_upwards(struct vm_area_struct *vma, unsigned long address) /* * vma is the first one with address < vma->vm_start. Have to extend vma. */ -int expand_downwards(struct vm_area_struct *vma, - unsigned long address) +int expand_downwards(struct vm_area_struct *vma, unsigned long address) { struct mm_struct *mm = vma->vm_mm; struct vm_area_struct *prev; int error = 0; - validate_mm(mm); address &= PAGE_MASK; if (address < mmap_min_addr) return -EPERM; @@ -2465,15 +2201,13 @@ int expand_downwards(struct vm_area_struct *vma, error = acct_stack_growth(vma, size, grow); if (!error) { /* - * vma_gap_update() doesn't support concurrent - * updates, but we only hold a shared mmap_lock - * lock here, so we need to protect against - * concurrent vma expansions. - * anon_vma_lock_write() doesn't help here, as - * we don't guarantee that all growable vmas - * in a mm share the same root anon vma. - * So, we reuse mm->page_table_lock to guard - * against concurrent vma expansions. + * We only hold a shared mmap_lock lock here, so + * we need to protect against concurrent vma + * expansions. anon_vma_lock_write() doesn't + * help here, as we don't guarantee that all + * growable vmas in a mm share the same root + * anon vma. So, we reuse mm->page_table_lock + * to guard against concurrent vma expansions. */ spin_lock(&mm->page_table_lock); if (vma->vm_flags & VM_LOCKED) @@ -2485,7 +2219,6 @@ int expand_downwards(struct vm_area_struct *vma, /* Overwrite old entry in mtree. */ vma_store(mm, vma); anon_vma_interval_tree_post_update_vma(vma); - vma_gap_update(vma); spin_unlock(&mm->page_table_lock); perf_event_mmap(vma); @@ -2494,7 +2227,6 @@ int expand_downwards(struct vm_area_struct *vma, } anon_vma_unlock_write(vma->anon_vma); khugepaged_enter_vma_merge(vma, vma->vm_flags); - validate_mm(mm); return error; } @@ -2627,16 +2359,14 @@ detach_vmas_to_be_unmapped(struct mm_struct *mm, struct vm_area_struct *vma, vma->vm_prev = NULL; vma_mt_szero(mm, vma->vm_start, end); do { - vma_rb_erase(vma, &mm->mm_rb); mm->map_count--; tail_vma = vma; vma = vma->vm_next; } while (vma && vma->vm_start < end); *insertion_point = vma; - if (vma) { + if (vma) vma->vm_prev = prev; - vma_gap_update(vma); - } else + else mm->highest_vm_end = prev ? vm_end_gap(prev) : 0; tail_vma->vm_next = NULL; @@ -2769,11 +2499,7 @@ int __do_munmap(struct mm_struct *mm, unsigned long start, size_t len, if (len == 0) return -EINVAL; - /* - * arch_unmap() might do unmaps itself. It must be called - * and finish any rbtree manipulation before this code - * runs and also starts to manipulate the rbtree. - */ + /* arch_unmap() might do unmaps itself. */ arch_unmap(mm, start, end); /* Find the first overlapping VMA where start < vma->vm_end */ @@ -2781,6 +2507,11 @@ int __do_munmap(struct mm_struct *mm, unsigned long start, size_t len, if (!vma) return 0; prev = vma->vm_prev; + /* we have start < vma->vm_end */ + + /* if it doesn't overlap, we have nothing.. */ + if (vma->vm_start >= end) + return 0; /* * If we need to split any vma, do it now to save pain later. @@ -2836,7 +2567,7 @@ int __do_munmap(struct mm_struct *mm, unsigned long start, size_t len, if (mm->locked_vm) unlock_range(vma, end); - /* Detach vmas from rbtree */ + /* Detach vmas from the MM linked list and remove from the mm tree*/ if (!detach_vmas_to_be_unmapped(mm, vma, prev, end)) downgrade = false; @@ -2981,11 +2712,11 @@ SYSCALL_DEFINE5(remap_file_pages, unsigned long, start, unsigned long, size, * anonymous maps. eventually we may be able to do some * brk-specific accounting here. */ -static int do_brk_flags(unsigned long addr, unsigned long len, unsigned long flags, struct list_head *uf) +static int do_brk_flags(unsigned long addr, unsigned long len, + unsigned long flags, struct list_head *uf) { struct mm_struct *mm = current->mm; struct vm_area_struct *vma, *prev; - struct rb_node **rb_link, *rb_parent; pgoff_t pgoff = addr >> PAGE_SHIFT; int error; unsigned long mapped_addr; @@ -3004,8 +2735,8 @@ static int do_brk_flags(unsigned long addr, unsigned long len, unsigned long fla if (error) return error; - /* Clear old maps, set up prev, rb_link, rb_parent, and uf */ - if (munmap_vma_range(mm, addr, len, &prev, &rb_link, &rb_parent, uf)) + /* Clear old maps, set up prev and uf */ + if (munmap_vma_range(mm, addr, len, &prev, uf)) return -ENOMEM; /* Check against address space limits *after* clearing old maps... */ @@ -3039,7 +2770,7 @@ 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); + vma_link(mm, vma, prev); out: perf_event_mmap(vma); mm->total_vm += len >> PAGE_SHIFT; @@ -3168,26 +2899,10 @@ 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; - 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)) + if (range_has_overlap(mm, vma->vm_start, vma->vm_end, &prev)) 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; @@ -3209,7 +2924,7 @@ 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, rb_link, rb_parent); + vma_link(mm, vma, prev); return 0; } @@ -3225,9 +2940,7 @@ struct vm_area_struct *copy_vma(struct vm_area_struct **vmap, unsigned long vma_start = vma->vm_start; struct mm_struct *mm = vma->vm_mm; 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); /* @@ -3239,10 +2952,9 @@ struct vm_area_struct *copy_vma(struct vm_area_struct **vmap, faulted_in_anon_vma = false; } - if (find_vma_links(mm, addr, addr + len, &prev, &rb_link, &rb_parent)) + if (range_has_overlap(mm, addr, addr + len, &prev)) 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); @@ -3283,7 +2995,7 @@ 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, rb_link, rb_parent); + vma_link(mm, new_vma, prev); *need_rmap_locks = false; } validate_mm_mt(mm); diff --git a/mm/nommu.c b/mm/nommu.c index 55a9e48a7a02..c5ded0f92a52 100644 --- a/mm/nommu.c +++ b/mm/nommu.c @@ -551,9 +551,9 @@ static void put_nommu_region(struct vm_region *region) */ static void add_vma_to_mm(struct mm_struct *mm, struct vm_area_struct *vma) { - struct vm_area_struct *pvma, *prev; struct address_space *mapping; - struct rb_node **p, *parent, *rb_prev; + struct vm_area_struct *prev; + MA_STATE(mas, &mm->mm_mt, vma->vm_start, vma->vm_end); BUG_ON(!vma->vm_region); @@ -571,42 +571,10 @@ static void add_vma_to_mm(struct mm_struct *mm, struct vm_area_struct *vma) i_mmap_unlock_write(mapping); } + prev = mas_prev(&mas, 0); + mas_reset(&mas); /* add the VMA to the tree */ - parent = rb_prev = NULL; - p = &mm->mm_rb.rb_node; - while (*p) { - parent = *p; - pvma = rb_entry(parent, struct vm_area_struct, vm_rb); - - /* sort by: start addr, end addr, VMA struct addr in that order - * (the latter is necessary as we may get identical VMAs) */ - if (vma->vm_start < pvma->vm_start) - p = &(*p)->rb_left; - else if (vma->vm_start > pvma->vm_start) { - rb_prev = parent; - p = &(*p)->rb_right; - } else if (vma->vm_end < pvma->vm_end) - p = &(*p)->rb_left; - else if (vma->vm_end > pvma->vm_end) { - rb_prev = parent; - p = &(*p)->rb_right; - } else if (vma < pvma) - p = &(*p)->rb_left; - else if (vma > pvma) { - rb_prev = parent; - p = &(*p)->rb_right; - } else - BUG(); - } - - rb_link_node(&vma->vm_rb, parent, p); - rb_insert_color(&vma->vm_rb, &mm->mm_rb); - - /* add VMA to the VMA list also */ - prev = NULL; - if (rb_prev) - prev = rb_entry(rb_prev, struct vm_area_struct, vm_rb); - + vma_mas_store(vma, &mas); __vma_link_list(mm, vma, prev); } @@ -619,6 +587,7 @@ static void delete_vma_from_mm(struct vm_area_struct *vma) struct address_space *mapping; struct mm_struct *mm = vma->vm_mm; struct task_struct *curr = current; + MA_STATE(mas, &vma->vm_mm->mm_mt, 0, 0); mm->map_count--; for (i = 0; i < VMACACHE_SIZE; i++) { @@ -641,8 +610,7 @@ static void delete_vma_from_mm(struct vm_area_struct *vma) } /* remove from the MM's tree and list */ - rb_erase(&vma->vm_rb, &mm->mm_rb); - + vma_mas_remove(vma, &mas); __vma_unlink_list(mm, vma); } @@ -666,24 +634,19 @@ static void delete_vma(struct mm_struct *mm, struct vm_area_struct *vma) struct vm_area_struct *find_vma(struct mm_struct *mm, unsigned long addr) { struct vm_area_struct *vma; + MA_STATE(mas, &mm->mm_mt, addr, addr); /* check the cache first */ vma = vmacache_find(mm, addr); if (likely(vma)) return vma; - /* trawl the list (there may be multiple mappings in which addr - * resides) */ - for (vma = mm->mmap; vma; vma = vma->vm_next) { - if (vma->vm_start > addr) - return NULL; - if (vma->vm_end > addr) { - vmacache_update(addr, vma); - return vma; - } - } + vma = mas_walk(&mas); - return NULL; + if (vma) + vmacache_update(addr, vma); + + return vma; } EXPORT_SYMBOL(find_vma); @@ -715,26 +678,23 @@ static struct vm_area_struct *find_vma_exact(struct mm_struct *mm, { struct vm_area_struct *vma; unsigned long end = addr + len; + MA_STATE(mas, &mm->mm_mt, addr, addr); /* check the cache first */ vma = vmacache_find_exact(mm, addr, end); if (vma) return vma; - /* trawl the list (there may be multiple mappings in which addr - * resides) */ - for (vma = mm->mmap; vma; vma = vma->vm_next) { - if (vma->vm_start < addr) - continue; - if (vma->vm_start > addr) - return NULL; - if (vma->vm_end == end) { - vmacache_update(addr, vma); - return vma; - } - } - - return NULL; + vma = mas_walk(&mas); + if (!vma) + return NULL; + if (vma->vm_start != addr) + return NULL; + if (vma->vm_end != end) + return NULL; + + vmacache_update(addr, vma); + return vma; } /* diff --git a/mm/util.c b/mm/util.c index e58151a61255..ab02382c2d57 100644 --- a/mm/util.c +++ b/mm/util.c @@ -287,6 +287,8 @@ void __vma_link_list(struct mm_struct *mm, struct vm_area_struct *vma, vma->vm_next = next; if (next) next->vm_prev = vma; + else + mm->highest_vm_end = vm_end_gap(vma); } void __vma_unlink_list(struct mm_struct *mm, struct vm_area_struct *vma) @@ -301,6 +303,12 @@ void __vma_unlink_list(struct mm_struct *mm, struct vm_area_struct *vma) mm->mmap = next; if (next) next->vm_prev = prev; + else { + if (prev) + mm->highest_vm_end = vm_end_gap(prev); + else + mm->highest_vm_end = 0; + } } /* Check if the vma is being used as a stack by this task */ -- 2.30.2