diff options
-rw-r--r-- | tools/testing/vma/vma.c | 1282 | ||||
-rw-r--r-- | tools/testing/vma/vma_internal.h | 45 |
2 files changed, 1317 insertions, 10 deletions
diff --git a/tools/testing/vma/vma.c b/tools/testing/vma/vma.c index 48e033c60d87..71bd30d5da81 100644 --- a/tools/testing/vma/vma.c +++ b/tools/testing/vma/vma.c @@ -7,13 +7,43 @@ #include "maple-shared.h" #include "vma_internal.h" +/* Include so header guard set. */ +#include "../../../mm/vma.h" + +static bool fail_prealloc; + +/* Then override vma_iter_prealloc() so we can choose to fail it. */ +#define vma_iter_prealloc(vmi, vma) \ + (fail_prealloc ? -ENOMEM : mas_preallocate(&(vmi)->mas, (vma), GFP_KERNEL)) + /* * Directly import the VMA implementation here. Our vma_internal.h wrapper * provides userland-equivalent functionality for everything vma.c uses. */ #include "../../../mm/vma.c" +/* + * Temporarily forward-ported from a future in which vmg's are used for merging. + */ +struct vma_merge_struct { + struct mm_struct *mm; + struct vma_iterator *vmi; + pgoff_t pgoff; + struct vm_area_struct *prev; + struct vm_area_struct *next; /* Modified by vma_merge(). */ + struct vm_area_struct *vma; /* Either a new VMA or the one being modified. */ + unsigned long start; + unsigned long end; + unsigned long flags; + struct file *file; + struct anon_vma *anon_vma; + struct mempolicy *policy; + struct vm_userfaultfd_ctx uffd_ctx; + struct anon_vma_name *anon_name; +}; + const struct vm_operations_struct vma_dummy_vm_ops; +static struct anon_vma dummy_anon_vma; #define ASSERT_TRUE(_expr) \ do { \ @@ -28,6 +58,14 @@ const struct vm_operations_struct vma_dummy_vm_ops; #define ASSERT_EQ(_val1, _val2) ASSERT_TRUE((_val1) == (_val2)) #define ASSERT_NE(_val1, _val2) ASSERT_TRUE((_val1) != (_val2)) +static struct task_struct __current; + +struct task_struct *get_current(void) +{ + return &__current; +} + +/* Helper function to simply allocate a VMA. */ static struct vm_area_struct *alloc_vma(struct mm_struct *mm, unsigned long start, unsigned long end, @@ -47,22 +85,201 @@ static struct vm_area_struct *alloc_vma(struct mm_struct *mm, return ret; } +/* Helper function to allocate a VMA and link it to the tree. */ +static struct vm_area_struct *alloc_and_link_vma(struct mm_struct *mm, + unsigned long start, + unsigned long end, + pgoff_t pgoff, + vm_flags_t flags) +{ + struct vm_area_struct *vma = alloc_vma(mm, start, end, pgoff, flags); + + if (vma == NULL) + return NULL; + + if (vma_link(mm, vma)) { + vm_area_free(vma); + return NULL; + } + + /* + * Reset this counter which we use to track whether writes have + * begun. Linking to the tree will have caused this to be incremented, + * which means we will get a false positive otherwise. + */ + vma->vm_lock_seq = -1; + + return vma; +} + +/* Helper function which provides a wrapper around a merge new VMA operation. */ +static struct vm_area_struct *merge_new(struct vma_merge_struct *vmg) +{ + /* vma_merge() needs a VMA to determine mm, anon_vma, and file. */ + struct vm_area_struct dummy = { + .vm_mm = vmg->mm, + .vm_flags = vmg->flags, + .anon_vma = vmg->anon_vma, + .vm_file = vmg->file, + }; + + /* + * For convenience, get prev and next VMAs. Which the new VMA operation + * requires. + */ + vmg->next = vma_next(vmg->vmi); + vmg->prev = vma_prev(vmg->vmi); + + vma_iter_set(vmg->vmi, vmg->start); + return vma_merge_new_vma(vmg->vmi, vmg->prev, &dummy, vmg->start, + vmg->end, vmg->pgoff); +} + +/* + * Helper function which provides a wrapper around a merge existing VMA + * operation. + */ +static struct vm_area_struct *merge_existing(struct vma_merge_struct *vmg) +{ + /* vma_merge() needs a VMA to determine mm, anon_vma, and file. */ + struct vm_area_struct dummy = { + .vm_mm = vmg->mm, + .vm_flags = vmg->flags, + .anon_vma = vmg->anon_vma, + .vm_file = vmg->file, + }; + + return vma_merge(vmg->vmi, vmg->prev, &dummy, vmg->start, vmg->end, + vmg->flags, vmg->pgoff, vmg->policy, vmg->uffd_ctx, + vmg->anon_name); +} + +/* + * Helper function which provides a wrapper around the expansion of an existing + * VMA. + */ +static int expand_existing(struct vma_merge_struct *vmg) +{ + return vma_expand(vmg->vmi, vmg->vma, vmg->start, vmg->end, vmg->pgoff, + vmg->next); +} + +/* + * Helper function to reset merge state the associated VMA iterator to a + * specified new range. + */ +static void vmg_set_range(struct vma_merge_struct *vmg, unsigned long start, + unsigned long end, pgoff_t pgoff, vm_flags_t flags) +{ + vma_iter_set(vmg->vmi, start); + + vmg->prev = NULL; + vmg->next = NULL; + vmg->vma = NULL; + + vmg->start = start; + vmg->end = end; + vmg->pgoff = pgoff; + vmg->flags = flags; +} + +/* + * Helper function to try to merge a new VMA. + * + * Update vmg and the iterator for it and try to merge, otherwise allocate a new + * VMA, link it to the maple tree and return it. + */ +static struct vm_area_struct *try_merge_new_vma(struct mm_struct *mm, + struct vma_merge_struct *vmg, + unsigned long start, unsigned long end, + pgoff_t pgoff, vm_flags_t flags, + bool *was_merged) +{ + struct vm_area_struct *merged; + + vmg_set_range(vmg, start, end, pgoff, flags); + + merged = merge_new(vmg); + if (merged) { + *was_merged = true; + return merged; + } + + *was_merged = false; + return alloc_and_link_vma(mm, start, end, pgoff, flags); +} + +/* + * Helper function to reset the dummy anon_vma to indicate it has not been + * duplicated. + */ +static void reset_dummy_anon_vma(void) +{ + dummy_anon_vma.was_cloned = false; + dummy_anon_vma.was_unlinked = false; +} + +/* + * Helper function to remove all VMAs and destroy the maple tree associated with + * a virtual address space. Returns a count of VMAs in the tree. + */ +static int cleanup_mm(struct mm_struct *mm, struct vma_iterator *vmi) +{ + struct vm_area_struct *vma; + int count = 0; + + fail_prealloc = false; + reset_dummy_anon_vma(); + + vma_iter_set(vmi, 0); + for_each_vma(*vmi, vma) { + vm_area_free(vma); + count++; + } + + mtree_destroy(&mm->mm_mt); + mm->map_count = 0; + return count; +} + +/* Helper function to determine if VMA has had vma_start_write() performed. */ +static bool vma_write_started(struct vm_area_struct *vma) +{ + int seq = vma->vm_lock_seq; + + /* We reset after each check. */ + vma->vm_lock_seq = -1; + + /* The vma_start_write() stub simply increments this value. */ + return seq > -1; +} + +/* Helper function providing a dummy vm_ops->close() method.*/ +static void dummy_close(struct vm_area_struct *) +{ +} + static bool test_simple_merge(void) { struct vm_area_struct *vma; unsigned long flags = VM_READ | VM_WRITE | VM_MAYREAD | VM_MAYWRITE; struct mm_struct mm = {}; struct vm_area_struct *vma_left = alloc_vma(&mm, 0, 0x1000, 0, flags); - struct vm_area_struct *vma_middle = alloc_vma(&mm, 0x1000, 0x2000, 1, flags); struct vm_area_struct *vma_right = alloc_vma(&mm, 0x2000, 0x3000, 2, flags); VMA_ITERATOR(vmi, &mm, 0x1000); + struct vma_merge_struct vmg = { + .mm = &mm, + .vmi = &vmi, + .start = 0x1000, + .end = 0x2000, + .flags = flags, + .pgoff = 1, + }; ASSERT_FALSE(vma_link(&mm, vma_left)); - ASSERT_FALSE(vma_link(&mm, vma_middle)); ASSERT_FALSE(vma_link(&mm, vma_right)); - vma = vma_merge_new_vma(&vmi, vma_left, vma_middle, 0x1000, - 0x2000, 1); + vma = merge_new(&vmg); ASSERT_NE(vma, NULL); ASSERT_EQ(vma->vm_start, 0); @@ -142,10 +359,17 @@ static bool test_simple_expand(void) struct mm_struct mm = {}; struct vm_area_struct *vma = alloc_vma(&mm, 0, 0x1000, 0, flags); VMA_ITERATOR(vmi, &mm, 0); + struct vma_merge_struct vmg = { + .vmi = &vmi, + .vma = vma, + .start = 0, + .end = 0x3000, + .pgoff = 0, + }; ASSERT_FALSE(vma_link(&mm, vma)); - ASSERT_FALSE(vma_expand(&vmi, vma, 0, 0x3000, 0, NULL)); + ASSERT_FALSE(expand_existing(&vmg)); ASSERT_EQ(vma->vm_start, 0); ASSERT_EQ(vma->vm_end, 0x3000); @@ -178,6 +402,1042 @@ static bool test_simple_shrink(void) return true; } +static bool test_merge_new(void) +{ + unsigned long flags = VM_READ | VM_WRITE | VM_MAYREAD | VM_MAYWRITE; + struct mm_struct mm = {}; + VMA_ITERATOR(vmi, &mm, 0); + struct vma_merge_struct vmg = { + .mm = &mm, + .vmi = &vmi, + }; + struct anon_vma_chain dummy_anon_vma_chain_a = { + .anon_vma = &dummy_anon_vma, + }; + struct anon_vma_chain dummy_anon_vma_chain_b = { + .anon_vma = &dummy_anon_vma, + }; + struct anon_vma_chain dummy_anon_vma_chain_c = { + .anon_vma = &dummy_anon_vma, + }; + struct anon_vma_chain dummy_anon_vma_chain_d = { + .anon_vma = &dummy_anon_vma, + }; + int count; + struct vm_area_struct *vma, *vma_a, *vma_b, *vma_c, *vma_d; + bool merged; + + /* + * 0123456789abc + * AA B CC + */ + vma_a = alloc_and_link_vma(&mm, 0, 0x2000, 0, flags); + ASSERT_NE(vma_a, NULL); + /* We give each VMA a single avc so we can test anon_vma duplication. */ + INIT_LIST_HEAD(&vma_a->anon_vma_chain); + list_add(&dummy_anon_vma_chain_a.same_vma, &vma_a->anon_vma_chain); + + vma_b = alloc_and_link_vma(&mm, 0x3000, 0x4000, 3, flags); + ASSERT_NE(vma_b, NULL); + INIT_LIST_HEAD(&vma_b->anon_vma_chain); + list_add(&dummy_anon_vma_chain_b.same_vma, &vma_b->anon_vma_chain); + + vma_c = alloc_and_link_vma(&mm, 0xb000, 0xc000, 0xb, flags); + ASSERT_NE(vma_c, NULL); + INIT_LIST_HEAD(&vma_c->anon_vma_chain); + list_add(&dummy_anon_vma_chain_c.same_vma, &vma_c->anon_vma_chain); + + /* + * NO merge. + * + * 0123456789abc + * AA B ** CC + */ + vma_d = try_merge_new_vma(&mm, &vmg, 0x7000, 0x9000, 7, flags, &merged); + ASSERT_NE(vma_d, NULL); + INIT_LIST_HEAD(&vma_d->anon_vma_chain); + list_add(&dummy_anon_vma_chain_d.same_vma, &vma_d->anon_vma_chain); + ASSERT_FALSE(merged); + ASSERT_EQ(mm.map_count, 4); + + /* + * Merge BOTH sides. + * + * 0123456789abc + * AA*B DD CC + */ + vma_b->anon_vma = &dummy_anon_vma; + vma = try_merge_new_vma(&mm, &vmg, 0x2000, 0x3000, 2, flags, &merged); + ASSERT_EQ(vma, vma_a); + /* Merge with A, delete B. */ + ASSERT_TRUE(merged); + ASSERT_EQ(vma->vm_start, 0); + ASSERT_EQ(vma->vm_end, 0x4000); + ASSERT_EQ(vma->vm_pgoff, 0); + ASSERT_EQ(vma->anon_vma, &dummy_anon_vma); + ASSERT_TRUE(vma_write_started(vma)); + ASSERT_EQ(mm.map_count, 3); + + /* + * Merge to PREVIOUS VMA. + * + * 0123456789abc + * AAAA* DD CC + */ + vma = try_merge_new_vma(&mm, &vmg, 0x4000, 0x5000, 4, flags, &merged); + ASSERT_EQ(vma, vma_a); + /* Extend A. */ + ASSERT_TRUE(merged); + ASSERT_EQ(vma->vm_start, 0); + ASSERT_EQ(vma->vm_end, 0x5000); + ASSERT_EQ(vma->vm_pgoff, 0); + ASSERT_EQ(vma->anon_vma, &dummy_anon_vma); + ASSERT_TRUE(vma_write_started(vma)); + ASSERT_EQ(mm.map_count, 3); + + /* + * Merge to NEXT VMA. + * + * 0123456789abc + * AAAAA *DD CC + */ + vma_d->anon_vma = &dummy_anon_vma; + vma = try_merge_new_vma(&mm, &vmg, 0x6000, 0x7000, 6, flags, &merged); + ASSERT_EQ(vma, vma_d); + /* Prepend. */ + ASSERT_TRUE(merged); + ASSERT_EQ(vma->vm_start, 0x6000); + ASSERT_EQ(vma->vm_end, 0x9000); + ASSERT_EQ(vma->vm_pgoff, 6); + ASSERT_EQ(vma->anon_vma, &dummy_anon_vma); + ASSERT_TRUE(vma_write_started(vma)); + ASSERT_EQ(mm.map_count, 3); + + /* + * Merge BOTH sides. + * + * 0123456789abc + * AAAAA*DDD CC + */ + vma = try_merge_new_vma(&mm, &vmg, 0x5000, 0x6000, 5, flags, &merged); + ASSERT_EQ(vma, vma_a); + /* Merge with A, delete D. */ + ASSERT_TRUE(merged); + ASSERT_EQ(vma->vm_start, 0); + ASSERT_EQ(vma->vm_end, 0x9000); + ASSERT_EQ(vma->vm_pgoff, 0); + ASSERT_EQ(vma->anon_vma, &dummy_anon_vma); + ASSERT_TRUE(vma_write_started(vma)); + ASSERT_EQ(mm.map_count, 2); + + /* + * Merge to NEXT VMA. + * + * 0123456789abc + * AAAAAAAAA *CC + */ + vma_c->anon_vma = &dummy_anon_vma; + vma = try_merge_new_vma(&mm, &vmg, 0xa000, 0xb000, 0xa, flags, &merged); + ASSERT_EQ(vma, vma_c); + /* Prepend C. */ + ASSERT_TRUE(merged); + ASSERT_EQ(vma->vm_start, 0xa000); + ASSERT_EQ(vma->vm_end, 0xc000); + ASSERT_EQ(vma->vm_pgoff, 0xa); + ASSERT_EQ(vma->anon_vma, &dummy_anon_vma); + ASSERT_TRUE(vma_write_started(vma)); + ASSERT_EQ(mm.map_count, 2); + + /* + * Merge BOTH sides. + * + * 0123456789abc + * AAAAAAAAA*CCC + */ + vma = try_merge_new_vma(&mm, &vmg, 0x9000, 0xa000, 0x9, flags, &merged); + ASSERT_EQ(vma, vma_a); + /* Extend A and delete C. */ + ASSERT_TRUE(merged); + ASSERT_EQ(vma->vm_start, 0); + ASSERT_EQ(vma->vm_end, 0xc000); + ASSERT_EQ(vma->vm_pgoff, 0); + ASSERT_EQ(vma->anon_vma, &dummy_anon_vma); + ASSERT_TRUE(vma_write_started(vma)); + ASSERT_EQ(mm.map_count, 1); + + /* + * Final state. + * + * 0123456789abc + * AAAAAAAAAAAAA + */ + + count = 0; + vma_iter_set(&vmi, 0); + for_each_vma(vmi, vma) { + ASSERT_NE(vma, NULL); + ASSERT_EQ(vma->vm_start, 0); + ASSERT_EQ(vma->vm_end, 0xc000); + ASSERT_EQ(vma->vm_pgoff, 0); + ASSERT_EQ(vma->anon_vma, &dummy_anon_vma); + + vm_area_free(vma); + count++; + } + + /* Should only have one VMA left (though freed) after all is done.*/ + ASSERT_EQ(count, 1); + + mtree_destroy(&mm.mm_mt); + return true; +} + +static bool test_vma_merge_special_flags(void) +{ + unsigned long flags = VM_READ | VM_WRITE | VM_MAYREAD | VM_MAYWRITE; + struct mm_struct mm = {}; + VMA_ITERATOR(vmi, &mm, 0); + struct vma_merge_struct vmg = { + .mm = &mm, + .vmi = &vmi, + }; + vm_flags_t special_flags[] = { VM_IO, VM_DONTEXPAND, VM_PFNMAP, VM_MIXEDMAP }; + vm_flags_t all_special_flags = 0; + int i; + struct vm_area_struct *vma_left, *vma; + + /* Make sure there aren't new VM_SPECIAL flags. */ + for (i = 0; i < ARRAY_SIZE(special_flags); i++) { + all_special_flags |= special_flags[i]; + } + ASSERT_EQ(all_special_flags, VM_SPECIAL); + + /* + * 01234 + * AAA + */ + vma_left = alloc_and_link_vma(&mm, 0, 0x3000, 0, flags); + ASSERT_NE(vma_left, NULL); + + /* 1. Set up new VMA with special flag that would otherwise merge. */ + + /* + * 01234 + * AAA* + * + * This should merge if not for the VM_SPECIAL flag. + */ + vmg_set_range(&vmg, 0x3000, 0x4000, 3, flags); + for (i = 0; i < ARRAY_SIZE(special_flags); i++) { + vm_flags_t special_flag = special_flags[i]; + + vma_left->__vm_flags = flags | special_flag; + vmg.flags = flags | special_flag; + vma = merge_new(&vmg); + ASSERT_EQ(vma, NULL); + } + + /* 2. Modify VMA with special flag that would otherwise merge. */ + + /* + * 01234 + * AAAB + * + * Create a VMA to modify. + */ + vma = alloc_and_link_vma(&mm, 0x3000, 0x4000, 3, flags); + ASSERT_NE(vma, NULL); + vmg.vma = vma; + + for (i = 0; i < ARRAY_SIZE(special_flags); i++) { + vm_flags_t special_flag = special_flags[i]; + + vma_left->__vm_flags = flags | special_flag; + vmg.flags = flags | special_flag; + vma = merge_existing(&vmg); + ASSERT_EQ(vma, NULL); + } + + cleanup_mm(&mm, &vmi); + return true; +} + +static bool test_vma_merge_with_close(void) +{ + unsigned long flags = VM_READ | VM_WRITE | VM_MAYREAD | VM_MAYWRITE; + struct mm_struct mm = {}; + VMA_ITERATOR(vmi, &mm, 0); + struct vma_merge_struct vmg = { + .mm = &mm, + .vmi = &vmi, + }; + const struct vm_operations_struct vm_ops = { + .close = dummy_close, + }; + struct vm_area_struct *vma_next = + alloc_and_link_vma(&mm, 0x2000, 0x3000, 2, flags); + struct vm_area_struct *vma; + + /* + * When we merge VMAs we sometimes have to delete others as part of the + * operation. + * + * Considering the two possible adjacent VMAs to which a VMA can be + * merged: + * + * [ prev ][ vma ][ next ] + * + * In no case will we need to delete prev. If the operation is + * mergeable, then prev will be extended with one or both of vma and + * next deleted. + * + * As a result, during initial mergeability checks, only + * can_vma_merge_before() (which implies the VMA being merged with is + * 'next' as shown above) bothers to check to see whether the next VMA + * has a vm_ops->close() callback that will need to be called when + * removed. + * + * If it does, then we cannot merge as the resources that the close() + * operation potentially clears down are tied only to the existing VMA + * range and we have no way of extending those to the nearly merged one. + * + * We must consider two scenarios: + * + * A. + * + * vm_ops->close: - - !NULL + * [ prev ][ vma ][ next ] + * + * Where prev may or may not be present/mergeable. + * + * This is picked up by a specific check in can_vma_merge_before(). + * + * B. + * + * vm_ops->close: - !NULL + * [ prev ][ vma ] + * + * Where prev and vma are present and mergeable. + * + * This is picked up by a specific check in the modified VMA merge. + * + * IMPORTANT NOTE: We make the assumption that the following case: + * + * - !NULL NULL + * [ prev ][ vma ][ next ] + * + * Cannot occur, because vma->vm_ops being the same implies the same + * vma->vm_file, and therefore this would mean that next->vm_ops->close + * would be set too, and thus scenario A would pick this up. + */ + + ASSERT_NE(vma_next, NULL); + + /* + * SCENARIO A + * + * 0123 + * *N + */ + + /* Make the next VMA have a close() callback. */ + vma_next->vm_ops = &vm_ops; + + /* Our proposed VMA has characteristics that would otherwise be merged. */ + vmg_set_range(&vmg, 0x1000, 0x2000, 1, flags); + + /* The next VMA having a close() operator should cause the merge to fail.*/ + ASSERT_EQ(merge_new(&vmg), NULL); + + /* Now create the VMA so we can merge via modified flags */ + vmg_set_range(&vmg, 0x1000, 0x2000, 1, flags); + vma = alloc_and_link_vma(&mm, 0x1000, 0x2000, 1, flags); + vmg.vma = vma; + + /* + * The VMA being modified in a way that would otherwise merge should + * also fail. + */ + ASSERT_EQ(merge_existing(&vmg), NULL); + + /* SCENARIO B + * + * 0123 + * P* + * + * In order for this scenario to trigger, the VMA currently being + * modified must also have a .close(). + */ + + /* Reset VMG state. */ + vmg_set_range(&vmg, 0x1000, 0x2000, 1, flags); + /* + * Make next unmergeable, and don't let the scenario A check pick this + * up, we want to reproduce scenario B only. + */ + vma_next->vm_ops = NULL; + vma_next->__vm_flags &= ~VM_MAYWRITE; + /* Allocate prev. */ + vmg.prev = alloc_and_link_vma(&mm, 0, 0x1000, 0, flags); + /* Assign a vm_ops->close() function to VMA explicitly. */ + vma->vm_ops = &vm_ops; + vmg.vma = vma; + /* Make sure merge does not occur. */ + ASSERT_EQ(merge_existing(&vmg), NULL); + + cleanup_mm(&mm, &vmi); + return true; +} + +static bool test_vma_merge_new_with_close(void) +{ + unsigned long flags = VM_READ | VM_WRITE | VM_MAYREAD | VM_MAYWRITE; + struct mm_struct mm = {}; + VMA_ITERATOR(vmi, &mm, 0); + struct vma_merge_struct vmg = { + .mm = &mm, + .vmi = &vmi, + }; + struct vm_area_struct *vma_prev = alloc_and_link_vma(&mm, 0, 0x2000, 0, flags); + struct vm_area_struct *vma_next = alloc_and_link_vma(&mm, 0x5000, 0x7000, 5, flags); + const struct vm_operations_struct vm_ops = { + .close = dummy_close, + }; + struct vm_area_struct *vma; + + /* + * We should allow the partial merge of a proposed new VMA if the + * surrounding VMAs have vm_ops->close() hooks (but are otherwise + * compatible), e.g.: + * + * New VMA + * A v-------v B + * |-----| |-----| + * close close + * + * Since the rule is to not DELETE a VMA with a close operation, this + * should be permitted, only rather than expanding A and deleting B, we + * should simply expand A and leave B intact, e.g.: + * + * New VMA + * A B + * |------------||-----| + * close close + */ + + /* Have prev and next have a vm_ops->close() hook. */ + vma_prev->vm_ops = &vm_ops; + vma_next->vm_ops = &vm_ops; + + vmg_set_range(&vmg, 0x2000, 0x5000, 2, flags); + vma = merge_new(&vmg); + ASSERT_NE(vma, NULL); + ASSERT_EQ(vma->vm_start, 0); + ASSERT_EQ(vma->vm_end, 0x5000); + ASSERT_EQ(vma->vm_pgoff, 0); + ASSERT_EQ(vma->vm_ops, &vm_ops); + ASSERT_TRUE(vma_write_started(vma)); + ASSERT_EQ(mm.map_count, 2); + + cleanup_mm(&mm, &vmi); + return true; +} + +static bool test_merge_existing(void) +{ + unsigned long flags = VM_READ | VM_WRITE | VM_MAYREAD | VM_MAYWRITE; + struct mm_struct mm = {}; + VMA_ITERATOR(vmi, &mm, 0); + struct vm_area_struct *vma, *vma_prev, *vma_next; + struct vma_merge_struct vmg = { + .mm = &mm, + .vmi = &vmi, + }; + + /* + * Merge right case - partial span. + * + * <-> + * 0123456789 + * VVVVNNN + * -> + * 0123456789 + * VNNNNNN + */ + vma = alloc_and_link_vma(&mm, 0x2000, 0x6000, 2, flags); + vma_next = alloc_and_link_vma(&mm, 0x6000, 0x9000, 6, flags); + vmg_set_range(&vmg, 0x3000, 0x6000, 3, flags); + vmg.vma = vma; + vmg.prev = vma; + vma->anon_vma = &dummy_anon_vma; + ASSERT_EQ(merge_existing(&vmg), vma_next); + ASSERT_EQ(vma_next->vm_start, 0x3000); + ASSERT_EQ(vma_next->vm_end, 0x9000); + ASSERT_EQ(vma_next->vm_pgoff, 3); + ASSERT_EQ(vma_next->anon_vma, &dummy_anon_vma); + ASSERT_EQ(vma->vm_start, 0x2000); + ASSERT_EQ(vma->vm_end, 0x3000); + ASSERT_EQ(vma->vm_pgoff, 2); + ASSERT_TRUE(vma_write_started(vma)); + ASSERT_TRUE(vma_write_started(vma_next)); + ASSERT_EQ(mm.map_count, 2); + + /* Clear down and reset. */ + ASSERT_EQ(cleanup_mm(&mm, &vmi), 2); + + /* + * Merge right case - full span. + * + * <--> + * 0123456789 + * VVVVNNN + * -> + * 0123456789 + * NNNNNNN + */ + vma = alloc_and_link_vma(&mm, 0x2000, 0x6000, 2, flags); + vma_next = alloc_and_link_vma(&mm, 0x6000, 0x9000, 6, flags); + vmg_set_range(&vmg, 0x2000, 0x6000, 2, flags); + vmg.vma = vma; + vma->anon_vma = &dummy_anon_vma; + ASSERT_EQ(merge_existing(&vmg), vma_next); + ASSERT_EQ(vma_next->vm_start, 0x2000); + ASSERT_EQ(vma_next->vm_end, 0x9000); + ASSERT_EQ(vma_next->vm_pgoff, 2); + ASSERT_EQ(vma_next->anon_vma, &dummy_anon_vma); + ASSERT_TRUE(vma_write_started(vma_next)); + ASSERT_EQ(mm.map_count, 1); + + /* Clear down and reset. We should have deleted vma. */ + ASSERT_EQ(cleanup_mm(&mm, &vmi), 1); + + /* + * Merge left case - partial span. + * + * <-> + * 0123456789 + * PPPVVVV + * -> + * 0123456789 + * PPPPPPV + */ + vma_prev = alloc_and_link_vma(&mm, 0, 0x3000, 0, flags); + vma = alloc_and_link_vma(&mm, 0x3000, 0x7000, 3, flags); + vmg_set_range(&vmg, 0x3000, 0x6000, 3, flags); + vmg.prev = vma_prev; + vmg.vma = vma; + vma->anon_vma = &dummy_anon_vma; + + ASSERT_EQ(merge_existing(&vmg), vma_prev); + ASSERT_EQ(vma_prev->vm_start, 0); + ASSERT_EQ(vma_prev->vm_end, 0x6000); + ASSERT_EQ(vma_prev->vm_pgoff, 0); + ASSERT_EQ(vma_prev->anon_vma, &dummy_anon_vma); + ASSERT_EQ(vma->vm_start, 0x6000); + ASSERT_EQ(vma->vm_end, 0x7000); + ASSERT_EQ(vma->vm_pgoff, 6); + ASSERT_TRUE(vma_write_started(vma_prev)); + ASSERT_TRUE(vma_write_started(vma)); + ASSERT_EQ(mm.map_count, 2); + + /* Clear down and reset. */ + ASSERT_EQ(cleanup_mm(&mm, &vmi), 2); + + /* + * Merge left case - full span. + * + * <--> + * 0123456789 + * PPPVVVV + * -> + * 0123456789 + * PPPPPPP + */ + vma_prev = alloc_and_link_vma(&mm, 0, 0x3000, 0, flags); + vma = alloc_and_link_vma(&mm, 0x3000, 0x7000, 3, flags); + vmg_set_range(&vmg, 0x3000, 0x7000, 3, flags); + vmg.prev = vma_prev; + vmg.vma = vma; + vma->anon_vma = &dummy_anon_vma; + ASSERT_EQ(merge_existing(&vmg), vma_prev); + ASSERT_EQ(vma_prev->vm_start, 0); + ASSERT_EQ(vma_prev->vm_end, 0x7000); + ASSERT_EQ(vma_prev->vm_pgoff, 0); + ASSERT_EQ(vma_prev->anon_vma, &dummy_anon_vma); + ASSERT_TRUE(vma_write_started(vma_prev)); + ASSERT_EQ(mm.map_count, 1); + + /* Clear down and reset. We should have deleted vma. */ + ASSERT_EQ(cleanup_mm(&mm, &vmi), 1); + + /* + * Merge both case. + * + * <--> + * 0123456789 + * PPPVVVVNNN + * -> + * 0123456789 + * PPPPPPPPPP + */ + vma_prev = alloc_and_link_vma(&mm, 0, 0x3000, 0, flags); + vma = alloc_and_link_vma(&mm, 0x3000, 0x7000, 3, flags); + vma_next = alloc_and_link_vma(&mm, 0x7000, 0x9000, 7, flags); + vmg_set_range(&vmg, 0x3000, 0x7000, 3, flags); + vmg.prev = vma_prev; + vmg.vma = vma; + vma->anon_vma = &dummy_anon_vma; + ASSERT_EQ(merge_existing(&vmg), vma_prev); + ASSERT_EQ(vma_prev->vm_start, 0); + ASSERT_EQ(vma_prev->vm_end, 0x9000); + ASSERT_EQ(vma_prev->vm_pgoff, 0); + ASSERT_EQ(vma_prev->anon_vma, &dummy_anon_vma); + ASSERT_TRUE(vma_write_started(vma_prev)); + ASSERT_EQ(mm.map_count, 1); + + /* Clear down and reset. We should have deleted prev and next. */ + ASSERT_EQ(cleanup_mm(&mm, &vmi), 1); + + /* + * Non-merge ranges. the modified VMA merge operation assumes that the + * caller always specifies ranges within the input VMA so we need only + * examine these cases. + * + * - + * - + * - + * <-> + * <> + * <> + * 0123456789a + * PPPVVVVVNNN + */ + + vma_prev = alloc_and_link_vma(&mm, 0, 0x3000, 0, flags); + vma = alloc_and_link_vma(&mm, 0x3000, 0x8000, 3, flags); + vma_next = alloc_and_link_vma(&mm, 0x8000, 0xa000, 8, flags); + + vmg_set_range(&vmg, 0x4000, 0x5000, 4, flags); + vmg.prev = vma; + vmg.vma = vma; + ASSERT_EQ(merge_existing(&vmg), NULL); + + vmg_set_range(&vmg, 0x5000, 0x6000, 5, flags); + vmg.prev = vma; + vmg.vma = vma; + ASSERT_EQ(merge_existing(&vmg), NULL); + + vmg_set_range(&vmg, 0x6000, 0x7000, 6, flags); + vmg.prev = vma; + vmg.vma = vma; + ASSERT_EQ(merge_existing(&vmg), NULL); + + vmg_set_range(&vmg, 0x4000, 0x7000, 4, flags); + vmg.prev = vma; + vmg.vma = vma; + ASSERT_EQ(merge_existing(&vmg), NULL); + + vmg_set_range(&vmg, 0x4000, 0x6000, 4, flags); + vmg.prev = vma; + vmg.vma = vma; + ASSERT_EQ(merge_existing(&vmg), NULL); + + vmg_set_range(&vmg, 0x5000, 0x6000, 5, flags); + vmg.prev = vma; + vmg.vma = vma; + ASSERT_EQ(merge_existing(&vmg), NULL); + + ASSERT_EQ(cleanup_mm(&mm, &vmi), 3); + + return true; +} + +static bool test_anon_vma_non_mergeable(void) +{ + unsigned long flags = VM_READ | VM_WRITE | VM_MAYREAD | VM_MAYWRITE; + struct mm_struct mm = {}; + VMA_ITERATOR(vmi, &mm, 0); + struct vm_area_struct *vma, *vma_prev, *vma_next; + struct vma_merge_struct vmg = { + .mm = &mm, + .vmi = &vmi, + }; + struct anon_vma_chain dummy_anon_vma_chain1 = { + .anon_vma = &dummy_anon_vma, + }; + struct anon_vma_chain dummy_anon_vma_chain2 = { + .anon_vma = &dummy_anon_vma, + }; + + /* + * In the case of modified VMA merge, merging both left and right VMAs + * but where prev and next have incompatible anon_vma objects, we revert + * to a merge of prev and VMA: + * + * <--> + * 0123456789 + * PPPVVVVNNN + * -> + * 0123456789 + * PPPPPPPNNN + */ + vma_prev = alloc_and_link_vma(&mm, 0, 0x3000, 0, flags); + vma = alloc_and_link_vma(&mm, 0x3000, 0x7000, 3, flags); + vma_next = alloc_and_link_vma(&mm, 0x7000, 0x9000, 7, flags); + + /* + * Give both prev and next single anon_vma_chain fields, so they will + * merge with the NULL vmg->anon_vma. + * + * However, when prev is compared to next, the merge should fail. + */ + + INIT_LIST_HEAD(&vma_prev->anon_vma_chain); + list_add(&dummy_anon_vma_chain1.same_vma, &vma_prev->anon_vma_chain); + ASSERT_TRUE(list_is_singular(&vma_prev->anon_vma_chain)); + vma_prev->anon_vma = &dummy_anon_vma; + ASSERT_TRUE(is_mergeable_anon_vma(NULL, vma_prev->anon_vma, vma_prev)); + + INIT_LIST_HEAD(&vma_next->anon_vma_chain); + list_add(&dummy_anon_vma_chain2.same_vma, &vma_next->anon_vma_chain); + ASSERT_TRUE(list_is_singular(&vma_next->anon_vma_chain)); + vma_next->anon_vma = (struct anon_vma *)2; + ASSERT_TRUE(is_mergeable_anon_vma(NULL, vma_next->anon_vma, vma_next)); + + ASSERT_FALSE(is_mergeable_anon_vma(vma_prev->anon_vma, vma_next->anon_vma, NULL)); + + vmg_set_range(&vmg, 0x3000, 0x7000, 3, flags); + vmg.prev = vma_prev; + vmg.vma = vma; + + ASSERT_EQ(merge_existing(&vmg), vma_prev); + ASSERT_EQ(vma_prev->vm_start, 0); + ASSERT_EQ(vma_prev->vm_end, 0x7000); + ASSERT_EQ(vma_prev->vm_pgoff, 0); + ASSERT_TRUE(vma_write_started(vma_prev)); + ASSERT_FALSE(vma_write_started(vma_next)); + + /* Clear down and reset. */ + ASSERT_EQ(cleanup_mm(&mm, &vmi), 2); + + /* + * Now consider the new VMA case. This is equivalent, only adding a new + * VMA in a gap between prev and next. + * + * <--> + * 0123456789 + * PPP****NNN + * -> + * 0123456789 + * PPPPPPPNNN + */ + vma_prev = alloc_and_link_vma(&mm, 0, 0x3000, 0, flags); + vma_next = alloc_and_link_vma(&mm, 0x7000, 0x9000, 7, flags); + + INIT_LIST_HEAD(&vma_prev->anon_vma_chain); + list_add(&dummy_anon_vma_chain1.same_vma, &vma_prev->anon_vma_chain); + vma_prev->anon_vma = (struct anon_vma *)1; + + INIT_LIST_HEAD(&vma_next->anon_vma_chain); + list_add(&dummy_anon_vma_chain2.same_vma, &vma_next->anon_vma_chain); + vma_next->anon_vma = (struct anon_vma *)2; + + vmg_set_range(&vmg, 0x3000, 0x7000, 3, flags); + vmg.prev = vma_prev; + + ASSERT_EQ(merge_new(&vmg), vma_prev); + ASSERT_EQ(vma_prev->vm_start, 0); + ASSERT_EQ(vma_prev->vm_end, 0x7000); + ASSERT_EQ(vma_prev->vm_pgoff, 0); + ASSERT_TRUE(vma_write_started(vma_prev)); + ASSERT_FALSE(vma_write_started(vma_next)); + + /* Final cleanup. */ + ASSERT_EQ(cleanup_mm(&mm, &vmi), 2); + + return true; +} + +static bool test_dup_anon_vma(void) +{ + unsigned long flags = VM_READ | VM_WRITE | VM_MAYREAD | VM_MAYWRITE; + struct mm_struct mm = {}; + VMA_ITERATOR(vmi, &mm, 0); + struct vma_merge_struct vmg = { + .mm = &mm, + .vmi = &vmi, + }; + struct anon_vma_chain dummy_anon_vma_chain = { + .anon_vma = &dummy_anon_vma, + }; + struct vm_area_struct *vma_prev, *vma_next, *vma; + + reset_dummy_anon_vma(); + + /* + * Expanding a VMA delete the next one duplicates next's anon_vma and + * assigns it to the expanded VMA. + * + * This covers new VMA merging, as these operations amount to a VMA + * expand. + */ + vma_prev = alloc_and_link_vma(&mm, 0, 0x3000, 0, flags); + vma_next = alloc_and_link_vma(&mm, 0x3000, 0x5000, 3, flags); + vma_next->anon_vma = &dummy_anon_vma; + + vmg_set_range(&vmg, 0, 0x5000, 0, flags); + vmg.vma = vma_prev; + vmg.next = vma_next; + + ASSERT_EQ(expand_existing(&vmg), 0); + + /* Will have been cloned. */ + ASSERT_EQ(vma_prev->anon_vma, &dummy_anon_vma); + ASSERT_TRUE(vma_prev->anon_vma->was_cloned); + + /* Cleanup ready for next run. */ + cleanup_mm(&mm, &vmi); + + /* + * next has anon_vma, we assign to prev. + * + * |<----->| + * |-------*********-------| + * prev vma next + * extend delete delete + */ + + vma_prev = alloc_and_link_vma(&mm, 0, 0x3000, 0, flags); + vma = alloc_and_link_vma(&mm, 0x3000, 0x5000, 3, flags); + vma_next = alloc_and_link_vma(&mm, 0x5000, 0x8000, 5, flags); + + /* Initialise avc so mergeability check passes. */ + INIT_LIST_HEAD(&vma_next->anon_vma_chain); + list_add(&dummy_anon_vma_chain.same_vma, &vma_next->anon_vma_chain); + + vma_next->anon_vma = &dummy_anon_vma; + vmg_set_range(&vmg, 0x3000, 0x5000, 3, flags); + vmg.prev = vma_prev; + vmg.vma = vma; + + ASSERT_EQ(merge_existing(&vmg), vma_prev); + + ASSERT_EQ(vma_prev->vm_start, 0); + ASSERT_EQ(vma_prev->vm_end, 0x8000); + + ASSERT_EQ(vma_prev->anon_vma, &dummy_anon_vma); + ASSERT_TRUE(vma_prev->anon_vma->was_cloned); + + cleanup_mm(&mm, &vmi); + + /* + * vma has anon_vma, we assign to prev. + * + * |<----->| + * |-------*********-------| + * prev vma next + * extend delete delete + */ + + vma_prev = alloc_and_link_vma(&mm, 0, 0x3000, 0, flags); + vma = alloc_and_link_vma(&mm, 0x3000, 0x5000, 3, flags); + vma_next = alloc_and_link_vma(&mm, 0x5000, 0x8000, 5, flags); + + vma->anon_vma = &dummy_anon_vma; + vmg_set_range(&vmg, 0x3000, 0x5000, 3, flags); + vmg.prev = vma_prev; + vmg.vma = vma; + + ASSERT_EQ(merge_existing(&vmg), vma_prev); + + ASSERT_EQ(vma_prev->vm_start, 0); + ASSERT_EQ(vma_prev->vm_end, 0x8000); + + ASSERT_EQ(vma_prev->anon_vma, &dummy_anon_vma); + ASSERT_TRUE(vma_prev->anon_vma->was_cloned); + + cleanup_mm(&mm, &vmi); + + /* + * vma has anon_vma, we assign to prev. + * + * |<----->| + * |-------************* + * prev vma + * extend shrink/delete + */ + + vma_prev = alloc_and_link_vma(&mm, 0, 0x3000, 0, flags); + vma = alloc_and_link_vma(&mm, 0x3000, 0x8000, 3, flags); + + vma->anon_vma = &dummy_anon_vma; + vmg_set_range(&vmg, 0x3000, 0x5000, 3, flags); + vmg.prev = vma_prev; + vmg.vma = vma; + + ASSERT_EQ(merge_existing(&vmg), vma_prev); + + ASSERT_EQ(vma_prev->vm_start, 0); + ASSERT_EQ(vma_prev->vm_end, 0x5000); + + ASSERT_EQ(vma_prev->anon_vma, &dummy_anon_vma); + ASSERT_TRUE(vma_prev->anon_vma->was_cloned); + + cleanup_mm(&mm, &vmi); + + /* + * vma has anon_vma, we assign to next. + * + * |<----->| + * *************-------| + * vma next + * shrink/delete extend + */ + + vma = alloc_and_link_vma(&mm, 0, 0x5000, 0, flags); + vma_next = alloc_and_link_vma(&mm, 0x5000, 0x8000, 5, flags); + + vma->anon_vma = &dummy_anon_vma; + vmg_set_range(&vmg, 0x3000, 0x5000, 3, flags); + vmg.prev = vma; + vmg.vma = vma; + + ASSERT_EQ(merge_existing(&vmg), vma_next); + + ASSERT_EQ(vma_next->vm_start, 0x3000); + ASSERT_EQ(vma_next->vm_end, 0x8000); + + ASSERT_EQ(vma_next->anon_vma, &dummy_anon_vma); + ASSERT_TRUE(vma_next->anon_vma->was_cloned); + + cleanup_mm(&mm, &vmi); + return true; +} + +static bool test_vmi_prealloc_fail(void) +{ + unsigned long flags = VM_READ | VM_WRITE | VM_MAYREAD | VM_MAYWRITE; + struct mm_struct mm = {}; + VMA_ITERATOR(vmi, &mm, 0); + struct vma_merge_struct vmg = { + .mm = &mm, + .vmi = &vmi, + }; + struct vm_area_struct *vma_prev, *vma; + + /* + * We are merging vma into prev, with vma possessing an anon_vma, which + * will be duplicated. We cause the vmi preallocation to fail and assert + * the duplicated anon_vma is unlinked. + */ + + vma_prev = alloc_and_link_vma(&mm, 0, 0x3000, 0, flags); + vma = alloc_and_link_vma(&mm, 0x3000, 0x5000, 3, flags); + vma->anon_vma = &dummy_anon_vma; + + vmg_set_range(&vmg, 0x3000, 0x5000, 3, flags); + vmg.prev = vma_prev; + vmg.vma = vma; + + fail_prealloc = true; + + /* This will cause the merge to fail. */ + ASSERT_EQ(merge_existing(&vmg), NULL); + /* We will already have assigned the anon_vma. */ + ASSERT_EQ(vma_prev->anon_vma, &dummy_anon_vma); + /* And it was both cloned and unlinked. */ + ASSERT_TRUE(dummy_anon_vma.was_cloned); + ASSERT_TRUE(dummy_anon_vma.was_unlinked); + + cleanup_mm(&mm, &vmi); /* Resets fail_prealloc too. */ + + /* + * We repeat the same operation for expanding a VMA, which is what new + * VMA merging ultimately uses too. This asserts that unlinking is + * performed in this case too. + */ + + vma_prev = alloc_and_link_vma(&mm, 0, 0x3000, 0, flags); + vma = alloc_and_link_vma(&mm, 0x3000, 0x5000, 3, flags); + vma->anon_vma = &dummy_anon_vma; + + vmg_set_range(&vmg, 0, 0x5000, 3, flags); + vmg.vma = vma_prev; + vmg.next = vma; + + fail_prealloc = true; + ASSERT_EQ(expand_existing(&vmg), -ENOMEM); + + ASSERT_EQ(vma_prev->anon_vma, &dummy_anon_vma); + ASSERT_TRUE(dummy_anon_vma.was_cloned); + ASSERT_TRUE(dummy_anon_vma.was_unlinked); + + cleanup_mm(&mm, &vmi); + return true; +} + +static bool test_merge_extend(void) +{ + unsigned long flags = VM_READ | VM_WRITE | VM_MAYREAD | VM_MAYWRITE; + struct mm_struct mm = {}; + VMA_ITERATOR(vmi, &mm, 0x1000); + struct vm_area_struct *vma; + + vma = alloc_and_link_vma(&mm, 0, 0x1000, 0, flags); + alloc_and_link_vma(&mm, 0x3000, 0x4000, 3, flags); + + /* + * Extend a VMA into the gap between itself and the following VMA. + * This should result in a merge. + * + * <-> + * * * + * + */ + + ASSERT_EQ(vma_merge_extend(&vmi, vma, 0x2000), vma); + ASSERT_EQ(vma->vm_start, 0); + ASSERT_EQ(vma->vm_end, 0x4000); + ASSERT_EQ(vma->vm_pgoff, 0); + ASSERT_TRUE(vma_write_started(vma)); + ASSERT_EQ(mm.map_count, 1); + + cleanup_mm(&mm, &vmi); + return true; +} + +static bool test_copy_vma(void) +{ + unsigned long flags = VM_READ | VM_WRITE | VM_MAYREAD | VM_MAYWRITE; + struct mm_struct mm = {}; + bool need_locks = false; + VMA_ITERATOR(vmi, &mm, 0); + struct vm_area_struct *vma, *vma_new, *vma_next; + + /* Move backwards and do not merge. */ + + vma = alloc_and_link_vma(&mm, 0x3000, 0x5000, 3, flags); + vma_new = copy_vma(&vma, 0, 0x2000, 0, &need_locks); + + ASSERT_NE(vma_new, vma); + ASSERT_EQ(vma_new->vm_start, 0); + ASSERT_EQ(vma_new->vm_end, 0x2000); + ASSERT_EQ(vma_new->vm_pgoff, 0); + + cleanup_mm(&mm, &vmi); + + /* Move a VMA into position next to another and merge the two. */ + + vma = alloc_and_link_vma(&mm, 0, 0x2000, 0, flags); + vma_next = alloc_and_link_vma(&mm, 0x6000, 0x8000, 6, flags); + vma_new = copy_vma(&vma, 0x4000, 0x2000, 4, &need_locks); + + ASSERT_EQ(vma_new, vma_next); + + cleanup_mm(&mm, &vmi); + return true; +} + int main(void) { int num_tests = 0, num_fail = 0; @@ -193,11 +1453,23 @@ int main(void) } \ } while (0) + /* Very simple tests to kick the tyres. */ TEST(simple_merge); TEST(simple_modify); TEST(simple_expand); TEST(simple_shrink); + TEST(merge_new); + TEST(vma_merge_special_flags); + TEST(vma_merge_with_close); + TEST(vma_merge_new_with_close); + TEST(merge_existing); + TEST(anon_vma_non_mergeable); + TEST(dup_anon_vma); + TEST(vmi_prealloc_fail); + TEST(merge_extend); + TEST(copy_vma); + #undef TEST printf("%d tests run, %d passed, %d failed.\n", diff --git a/tools/testing/vma/vma_internal.h b/tools/testing/vma/vma_internal.h index 093560e5b2ac..a3c262c6eb73 100644 --- a/tools/testing/vma/vma_internal.h +++ b/tools/testing/vma/vma_internal.h @@ -81,8 +81,6 @@ #define AS_MM_ALL_LOCKS 2 -#define current NULL - /* We hardcode this for now. */ #define sysctl_max_map_count 0x1000000UL @@ -92,6 +90,12 @@ typedef struct pgprot { pgprotval_t pgprot; } pgprot_t; typedef unsigned long vm_flags_t; typedef __bitwise unsigned int vm_fault_t; +/* + * The shared stubs do not implement this, it amounts to an fprintf(STDERR,...) + * either way :) + */ +#define pr_warn_once pr_err + typedef struct refcount_struct { atomic_t refs; } refcount_t; @@ -100,9 +104,30 @@ struct kref { refcount_t refcount; }; +/* + * Define the task command name length as enum, then it can be visible to + * BPF programs. + */ +enum { + TASK_COMM_LEN = 16, +}; + +struct task_struct { + char comm[TASK_COMM_LEN]; + pid_t pid; + struct mm_struct *mm; +}; + +struct task_struct *get_current(void); +#define current get_current() + struct anon_vma { struct anon_vma *root; struct rb_root_cached rb_root; + + /* Test fields. */ + bool was_cloned; + bool was_unlinked; }; struct anon_vma_chain { @@ -682,13 +707,21 @@ static inline int vma_dup_policy(struct vm_area_struct *, struct vm_area_struct return 0; } -static inline int anon_vma_clone(struct vm_area_struct *, struct vm_area_struct *) +static inline int anon_vma_clone(struct vm_area_struct *dst, struct vm_area_struct *src) { + /* For testing purposes. We indicate that an anon_vma has been cloned. */ + if (src->anon_vma != NULL) { + dst->anon_vma = src->anon_vma; + dst->anon_vma->was_cloned = true; + } + return 0; } -static inline void vma_start_write(struct vm_area_struct *) +static inline void vma_start_write(struct vm_area_struct *vma) { + /* Used to indicate to tests that a write operation has begun. */ + vma->vm_lock_seq++; } static inline void vma_adjust_trans_huge(struct vm_area_struct *vma, @@ -759,8 +792,10 @@ static inline void vma_assert_write_locked(struct vm_area_struct *) { } -static inline void unlink_anon_vmas(struct vm_area_struct *) +static inline void unlink_anon_vmas(struct vm_area_struct *vma) { + /* For testing purposes, indicate that the anon_vma was unlinked. */ + vma->anon_vma->was_unlinked = true; } static inline void anon_vma_unlock_write(struct anon_vma *) |