diff options
Diffstat (limited to 'mm')
| -rw-r--r-- | mm/mremap.c | 6 | ||||
| -rw-r--r-- | mm/vma.c | 56 | ||||
| -rw-r--r-- | mm/vma.h | 127 | ||||
| -rw-r--r-- | mm/vma_exec.c | 2 |
4 files changed, 144 insertions, 47 deletions
diff --git a/mm/mremap.c b/mm/mremap.c index b64aa1f6e07e..f07fc4e3ef2e 100644 --- a/mm/mremap.c +++ b/mm/mremap.c @@ -1265,7 +1265,9 @@ static void unmap_source_vma(struct vma_remap_struct *vrm) static int copy_vma_and_data(struct vma_remap_struct *vrm, struct vm_area_struct **new_vma_ptr) { - const unsigned long new_pgoff = linear_page_index(vrm->vma, vrm->addr); + const pgoff_t new_pgoff = linear_page_index(vrm->vma, vrm->addr); + const pgoff_t new_virt_pgoff = + __linear_virt_page_index(vrm->vma, vrm->addr); struct vm_area_struct *vma = vrm->vma; struct vm_area_struct *new_vma; unsigned long moved_len; @@ -1273,7 +1275,7 @@ static int copy_vma_and_data(struct vma_remap_struct *vrm, PAGETABLE_MOVE(pmc, NULL, NULL, vrm->addr, vrm->new_addr, vrm->old_len); new_vma = copy_vma(&vma, vrm->new_addr, vrm->new_len, new_pgoff, - &pmc.need_rmap_locks); + new_virt_pgoff, &pmc.need_rmap_locks); if (!new_vma) { vrm_uncharge(vrm); *new_vma_ptr = NULL; @@ -18,6 +18,7 @@ struct mmap_state { unsigned long addr; unsigned long end; pgoff_t pgoff; + pgoff_t virt_pgoff; unsigned long pglen; union { vm_flags_t vm_flags; @@ -46,13 +47,22 @@ struct mmap_state { bool file_doesnt_need_get :1; }; -#define MMAP_STATE(name, mm_, vmi_, addr_, len_, pgoff_, vma_flags_, file_) \ +static inline pgoff_t map_anon_pgoff(const struct mmap_state *map) +{ + if (vma_flags_test(&map->vma_flags, VMA_SHARED_BIT)) + return map->pgoff; + + return map->virt_pgoff; +} + +#define MMAP_STATE(name, mm_, vmi_, addr_, len_, pgoff_, virt_pgoff_, vma_flags_, file_) \ struct mmap_state name = { \ .mm = mm_, \ .vmi = vmi_, \ .addr = addr_, \ .end = (addr_) + (len_), \ .pgoff = pgoff_, \ + .virt_pgoff = virt_pgoff_, \ .pglen = PHYS_PFN(len_), \ .vma_flags = vma_flags_, \ .file = file_, \ @@ -67,6 +77,7 @@ struct mmap_state { .end = (map_)->end, \ .vma_flags = (map_)->vma_flags, \ .pgoff = (map_)->pgoff, \ + .anon_pgoff = map_anon_pgoff(map_), \ .file = (map_)->file, \ .prev = (map_)->prev, \ .middle = vma_, \ @@ -82,10 +93,11 @@ static void __vma_set_range(struct vm_area_struct *vma, unsigned long start, } static void vma_set_range(struct vm_area_struct *vma, unsigned long start, - unsigned long end, pgoff_t pgoff) + unsigned long end, pgoff_t pgoff, pgoff_t virt_pgoff) { __vma_set_range(vma, start, end); vma_set_pgoff(vma, pgoff); + vma_set_virt_pgoff(vma, virt_pgoff); } /* Was this VMA ever forked from a parent, i.e. maybe contains CoW mappings? */ @@ -812,7 +824,8 @@ static int commit_merge(struct vma_merge_struct *vmg) */ vma_adjust_trans_huge(vma, vmg->start, vmg->end, vmg->__adjust_middle_start ? vmg->middle : NULL); - vma_set_range(vma, vmg->start, vmg->end, vmg_start_pgoff(vmg)); + vma_set_range(vma, vmg->start, vmg->end, vmg_start_pgoff(vmg), + vmg_start_anon_pgoff(vmg)); vmg_adjust_set_range(vmg); vma_iter_store_overwrite(vmg->vmi, vmg->target); @@ -982,6 +995,7 @@ static __must_check struct vm_area_struct *vma_merge_existing_range( vmg->start = prev->vm_start; vmg->end = next->vm_end; vmg->pgoff = vma_start_pgoff(prev); + vmg->anon_pgoff = vma_start_anon_pgoff(prev); /* * We already ensured anon_vma compatibility above, so now it's @@ -1000,6 +1014,7 @@ static __must_check struct vm_area_struct *vma_merge_existing_range( */ vmg->start = prev->vm_start; vmg->pgoff = vma_start_pgoff(prev); + vmg->anon_pgoff = vma_start_anon_pgoff(prev); if (!vmg->__remove_middle) vmg->__adjust_middle_start = true; @@ -1022,12 +1037,14 @@ static __must_check struct vm_area_struct *vma_merge_existing_range( if (vmg->__remove_middle) { vmg->end = next->vm_end; vmg->pgoff = vma_start_pgoff(next) - pglen; + vmg->anon_pgoff = vma_start_anon_pgoff(next) - pglen; } else { /* We shrink middle and expand next. */ vmg->__adjust_next_start = true; vmg->start = middle->vm_start; vmg->end = start; vmg->pgoff = vma_start_pgoff(middle); + vmg->anon_pgoff = vma_start_anon_pgoff(middle); } err = dup_anon_vma(next, middle, &anon_dup); @@ -1137,6 +1154,7 @@ struct vm_area_struct *vma_merge_new_range(struct vma_merge_struct *vmg) vmg->start = prev->vm_start; vmg->target = prev; vmg->pgoff = vma_start_pgoff(prev); + vmg->anon_pgoff = vma_start_anon_pgoff(prev); /* * If this merge would result in removal of the next VMA but we @@ -1908,9 +1926,10 @@ static int vma_link(struct mm_struct *mm, struct vm_area_struct *vma) */ struct vm_area_struct *copy_vma(struct vm_area_struct **vmap, unsigned long addr, unsigned long len, pgoff_t pgoff, - bool *need_rmap_locks) + pgoff_t virt_pgoff, bool *need_rmap_locks) { struct vm_area_struct *vma = *vmap; + const bool is_shared = vma_test(vma, VMA_SHARED_BIT); unsigned long vma_start = vma->vm_start; struct mm_struct *mm = vma->vm_mm; struct vm_area_struct *new_vma; @@ -1919,11 +1938,14 @@ struct vm_area_struct *copy_vma(struct vm_area_struct **vmap, VMG_VMA_STATE(vmg, &vmi, NULL, vma, addr, addr + len); /* - * If anonymous vma has not yet been faulted, update new pgoff - * to match new location, to increase its chance of merging. + * If a vma has not yet been faulted, update its virtual pgoff to match + * the new location to increase its chance of merging. */ - if (unlikely(vma_is_anonymous(vma) && !vma->anon_vma)) { - pgoff = addr >> PAGE_SHIFT; + if (!vma->anon_vma && !is_shared) { + virt_pgoff = addr >> PAGE_SHIFT; + + if (vma_is_anonymous(vma)) + pgoff = virt_pgoff; faulted_in_anon_vma = false; } @@ -1940,6 +1962,7 @@ struct vm_area_struct *copy_vma(struct vm_area_struct **vmap, return NULL; /* should never get here */ vmg.pgoff = pgoff; + vmg.anon_pgoff = is_shared ? pgoff : virt_pgoff; vmg.next = vma_iter_next_rewind(&vmi, NULL); new_vma = vma_merge_copied_range(&vmg); @@ -1961,7 +1984,7 @@ struct vm_area_struct *copy_vma(struct vm_area_struct **vmap, * safe. It is only safe to keep the vm_pgoff * linear if there are no pages mapped yet. */ - VM_BUG_ON_VMA(faulted_in_anon_vma, new_vma); + VM_WARN_ON_ONCE_VMA(faulted_in_anon_vma, new_vma); *vmap = vma = new_vma; } *need_rmap_locks = @@ -1970,7 +1993,7 @@ struct vm_area_struct *copy_vma(struct vm_area_struct **vmap, new_vma = vm_area_dup(vma); if (!new_vma) goto out; - vma_set_range(new_vma, addr, addr + len, pgoff); + vma_set_range(new_vma, addr, addr + len, pgoff, virt_pgoff); if (vma_dup_policy(vma, new_vma)) goto out_free_vma; if (anon_vma_clone(new_vma, vma, VMA_OP_REMAP)) @@ -2612,7 +2635,7 @@ static int __mmap_new_vma(struct mmap_state *map, struct vm_area_struct **vmap, if (is_anon) vma_set_anonymous(vma); - vma_set_range(vma, map->addr, map->end, map->pgoff); + vma_set_range(vma, map->addr, map->end, map->pgoff, map->virt_pgoff); vma->flags = map->vma_flags; vma->vm_page_prot = map->page_prot; @@ -2801,7 +2824,8 @@ static unsigned long __mmap_region(struct file *file, unsigned long addr, struct vm_area_struct *vma = NULL; bool have_mmap_prepare = file && file->f_op->mmap_prepare; VMA_ITERATOR(vmi, mm, addr); - MMAP_STATE(map, mm, &vmi, addr, len, pgoff, vma_flags, file); + const pgoff_t virt_pgoff = addr >> PAGE_SHIFT; + MMAP_STATE(map, mm, &vmi, addr, len, pgoff, virt_pgoff, vma_flags, file); struct vm_area_desc desc = { .mm = mm, .file = file, @@ -2946,6 +2970,7 @@ int do_brk_flags(struct vma_iterator *vmi, struct vm_area_struct *vma, unsigned long addr, unsigned long len, vma_flags_t vma_flags) { struct mm_struct *mm = current->mm; + const pgoff_t pgoff = addr >> PAGE_SHIFT; /* * Check against address space limits by the changed size @@ -2970,7 +2995,7 @@ int do_brk_flags(struct vma_iterator *vmi, struct vm_area_struct *vma, * occur after forking, so the expand will only happen on new VMAs. */ if (vma && vma->vm_end == addr) { - VMG_STATE(vmg, mm, vmi, addr, addr + len, vma_flags, PHYS_PFN(addr)); + VMG_STATE(vmg, mm, vmi, addr, addr + len, vma_flags, pgoff, pgoff); vmg.prev = vma; /* vmi is positioned at prev, which this mode expects. */ @@ -2990,7 +3015,7 @@ int do_brk_flags(struct vma_iterator *vmi, struct vm_area_struct *vma, goto unacct_fail; vma_set_anonymous(vma); - vma_set_range(vma, addr, addr + len, addr >> PAGE_SHIFT); + vma_set_range(vma, addr, addr + len, pgoff, pgoff); vma->flags = vma_flags; vma->vm_page_prot = vm_get_page_prot(vma_flags_to_legacy(vma_flags)); vma_start_write(vma); @@ -3382,6 +3407,7 @@ int insert_vm_struct(struct mm_struct *mm, struct vm_area_struct *vma) WARN_ON_ONCE(vma->anon_vma); vma_set_pgoff(vma, vma->vm_start >> PAGE_SHIFT); } + vma_set_virt_pgoff(vma, vma->vm_start >> PAGE_SHIFT); if (vma_link(mm, vma)) { if (vma_test(vma, VMA_ACCOUNT_BIT)) @@ -3437,7 +3463,7 @@ struct vm_area_struct *__install_special_mapping( vma->vm_ops = ops; vma->vm_private_data = priv; - vma_set_range(vma, addr, addr + len, 0); + vma_set_range(vma, addr, addr + len, 0, addr >> PAGE_SHIFT); ret = insert_vm_struct(mm, vma); if (ret) @@ -104,6 +104,7 @@ struct vma_merge_struct { unsigned long start; unsigned long end; pgoff_t pgoff; + pgoff_t anon_pgoff; union { /* Temporary while VMA flags are being converted. */ @@ -237,11 +238,6 @@ static inline bool vmg_nomem(struct vma_merge_struct *vmg) return vmg->state == VMA_MERGE_ERROR_NOMEM; } -static inline pgoff_t vmg_start_pgoff(const struct vma_merge_struct *vmg) -{ - return vmg->pgoff; -} - static inline pgoff_t vmg_pages(const struct vma_merge_struct *vmg) { const unsigned long size = vmg->end - vmg->start; @@ -249,6 +245,11 @@ static inline pgoff_t vmg_pages(const struct vma_merge_struct *vmg) return size >> PAGE_SHIFT; } +static inline pgoff_t vmg_start_pgoff(const struct vma_merge_struct *vmg) +{ + return vmg->pgoff; +} + static inline pgoff_t vmg_end_pgoff(const struct vma_merge_struct *vmg) { return vmg_start_pgoff(vmg) + vmg_pages(vmg); @@ -283,6 +284,16 @@ static inline void vma_set_pgoff(struct vm_area_struct *vma, pgoff_t pgoff) vma->vm_pgoff = pgoff; } +static inline pgoff_t vmg_start_anon_pgoff(const struct vma_merge_struct *vmg) +{ + return vmg->anon_pgoff; +} + +static inline pgoff_t vmg_end_anon_pgoff(const struct vma_merge_struct *vmg) +{ + return vmg_start_anon_pgoff(vmg) + vmg_pages(vmg); +} + static inline void __vma_set_virt_pgoff(struct vm_area_struct *vma, pgoff_t pgoff) { #ifdef CONFIG_64BIT @@ -301,44 +312,102 @@ static inline void vma_add_pgoff(struct vm_area_struct *vma, pgoff_t delta) { vma_assert_can_modify(vma); vma_set_pgoff(vma, vma_start_pgoff(vma) + delta); + vma_set_virt_pgoff(vma, vma_start_virt_pgoff(vma) + delta); } static inline void vma_sub_pgoff(struct vm_area_struct *vma, pgoff_t delta) { vma_assert_can_modify(vma); vma_set_pgoff(vma, vma_start_pgoff(vma) - delta); + vma_set_virt_pgoff(vma, vma_start_virt_pgoff(vma) - delta); +} + +/** + * vma_anon_pgoff_addr() - Calculates the absolute anonymous page offset of + * @address. + * @vma: The VMA whose anonymous page offset is required. + * @address: The address whose absolute page offset is required. + * + * If the VMA is a shared file-backed mapping, then the file-based page offset + * is returned. + * + * Otherwise, the virtual page offset is returned. + * + * This means that shared file-backed mappings are correctly merged based on + * their file page offset compatibility. + * + * Returns: The absolute anonymous page offset of @address within @vma. + */ +static inline pgoff_t vma_anon_pgoff_addr(const struct vm_area_struct *vma, + unsigned long address) +{ + if (vma_test(vma, VMA_SHARED_BIT)) + return linear_page_index(vma, address); + + return linear_virt_page_index(vma, address); +} + +/** + * vma_start_anon_pgoff() - Calculates the absolute anonymous page offset used + * for purposes of merge compatibility. + * @vma: The VMA whose anonymous page offset is required. + * + * See vma_anon_pgoff_addr(). + * + * Returns: The absolute anonymous page offset of @vma for purposes of merging. + */ +static inline pgoff_t vma_start_anon_pgoff(const struct vm_area_struct *vma) +{ + return vma_anon_pgoff_addr(vma, vma->vm_start); } -#define VMG_STATE(name, mm_, vmi_, start_, end_, vma_flags_, pgoff_) \ +/** + * vma_end_anon_pgoff() - Calculates the absolute exclusive end anonymous page + * offset used for purposes of merge compatibility. + * @vma: The VMA whose anonymous end page offset is required. + * + * See vma_start_anon_pgoff(). + * + * Returns: The absolute exclusive end anonymous page offset of @vma for + * purposes of merging. + */ +static inline pgoff_t vma_end_anon_pgoff(const struct vm_area_struct *vma) +{ + return vma_start_anon_pgoff(vma) + vma_pages(vma); +} + +#define VMG_STATE(name, mm_, vmi_, start_, end_, vma_flags_, pgoff_, anon_pgoff_) \ + struct vma_merge_struct name = { \ + .mm = mm_, \ + .vmi = vmi_, \ + .start = start_, \ + .end = end_, \ + .vma_flags = vma_flags_, \ + .pgoff = pgoff_, \ + .anon_pgoff = anon_pgoff_, \ + .state = VMA_MERGE_START, \ + } + +#define VMG_VMA_STATE(name, vmi_, prev_, vma_, start_, end_) \ struct vma_merge_struct name = { \ - .mm = mm_, \ + .mm = vma_->vm_mm, \ .vmi = vmi_, \ + .prev = prev_, \ + .middle = vma_, \ + .next = NULL, \ .start = start_, \ .end = end_, \ - .vma_flags = vma_flags_, \ - .pgoff = pgoff_, \ + .vm_flags = vma_->vm_flags, \ + .pgoff = linear_page_index(vma_, start_), \ + .anon_pgoff = vma_anon_pgoff_addr(vma_, start_), \ + .file = vma_->vm_file, \ + .anon_vma = vma_->anon_vma, \ + .policy = vma_policy(vma_), \ + .uffd_ctx = vma_->vm_userfaultfd_ctx, \ + .anon_name = anon_vma_name(vma_), \ .state = VMA_MERGE_START, \ } -#define VMG_VMA_STATE(name, vmi_, prev_, vma_, start_, end_) \ - struct vma_merge_struct name = { \ - .mm = vma_->vm_mm, \ - .vmi = vmi_, \ - .prev = prev_, \ - .middle = vma_, \ - .next = NULL, \ - .start = start_, \ - .end = end_, \ - .vm_flags = vma_->vm_flags, \ - .pgoff = linear_page_index(vma_, start_), \ - .file = vma_->vm_file, \ - .anon_vma = vma_->anon_vma, \ - .policy = vma_policy(vma_), \ - .uffd_ctx = vma_->vm_userfaultfd_ctx, \ - .anon_name = anon_vma_name(vma_), \ - .state = VMA_MERGE_START, \ - } - #ifdef CONFIG_DEBUG_VM_MAPLE_TREE void validate_mm(struct mm_struct *mm); #else @@ -520,7 +589,7 @@ void unlink_file_vma_batch_add(struct unlink_vma_file_batch *vb, struct vm_area_struct *copy_vma(struct vm_area_struct **vmap, unsigned long addr, unsigned long len, pgoff_t pgoff, - bool *need_rmap_locks); + pgoff_t anon_pgoff, bool *need_rmap_locks); struct anon_vma *find_mergeable_anon_vma(struct vm_area_struct *vma); diff --git a/mm/vma_exec.c b/mm/vma_exec.c index 7af1260689b9..586c52155942 100644 --- a/mm/vma_exec.c +++ b/mm/vma_exec.c @@ -41,7 +41,7 @@ int relocate_vma_down(struct vm_area_struct *vma, unsigned long shift) unsigned long new_end = old_end - shift; VMA_ITERATOR(vmi, mm, new_start); VMG_STATE(vmg, mm, &vmi, new_start, old_end, EMPTY_VMA_FLAGS, - vma_start_pgoff(vma)); + vma_start_pgoff(vma), vma_start_anon_pgoff(vma)); struct vm_area_struct *next; struct mmu_gather tlb; PAGETABLE_MOVE(pmc, vma, vma, old_start, new_start, length); |