From 9760ebffbf5507320e0de41f5b80089bdef996a0 Mon Sep 17 00:00:00 2001 From: "Liam R. Howlett" Date: Fri, 20 Jan 2023 11:26:30 -0500 Subject: mm: switch vma_merge(), split_vma(), and __split_vma to vma iterator Drop the vmi_* functions and transition all users to use the vma iterator directly. Link: https://lkml.kernel.org/r/20230120162650.984577-30-Liam.Howlett@oracle.com Signed-off-by: Liam R. Howlett Signed-off-by: Andrew Morton --- mm/mmap.c | 79 ++++++++++++++++++--------------------------------------------- 1 file changed, 22 insertions(+), 57 deletions(-) (limited to 'mm/mmap.c') diff --git a/mm/mmap.c b/mm/mmap.c index 8806bfbaa505..afc65f122f7d 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -1010,7 +1010,7 @@ can_vma_merge_after(struct vm_area_struct *vma, unsigned long vm_flags, * parameter) may establish ptes with the wrong permissions of NNNN * instead of the right permissions of XXXX. */ -struct vm_area_struct *vma_merge(struct mm_struct *mm, +struct vm_area_struct *vma_merge(struct vma_iterator *vmi, struct mm_struct *mm, struct vm_area_struct *prev, unsigned long addr, unsigned long end, unsigned long vm_flags, struct anon_vma *anon_vma, struct file *file, @@ -1019,7 +1019,7 @@ struct vm_area_struct *vma_merge(struct mm_struct *mm, struct anon_vma_name *anon_name) { pgoff_t pglen = (end - addr) >> PAGE_SHIFT; - struct vm_area_struct *mid, *next, *res; + struct vm_area_struct *mid, *next, *res = NULL; int err = -1; bool merge_prev = false; bool merge_next = false; @@ -1085,26 +1085,11 @@ struct vm_area_struct *vma_merge(struct mm_struct *mm, if (err) return NULL; khugepaged_enter_vma(res, vm_flags); - return res; -} -struct vm_area_struct *vmi_vma_merge(struct vma_iterator *vmi, - struct mm_struct *mm, - struct vm_area_struct *prev, unsigned long addr, - unsigned long end, unsigned long vm_flags, - struct anon_vma *anon_vma, struct file *file, - pgoff_t pgoff, struct mempolicy *policy, - struct vm_userfaultfd_ctx vm_userfaultfd_ctx, - struct anon_vma_name *anon_name) -{ - struct vm_area_struct *tmp; - - tmp = vma_merge(mm, prev, addr, end, vm_flags, anon_vma, file, pgoff, - policy, vm_userfaultfd_ctx, anon_name); - if (tmp) + if (res) vma_iter_set(vmi, end); - return tmp; + return res; } /* @@ -2228,12 +2213,14 @@ static void unmap_region(struct mm_struct *mm, struct maple_tree *mt, * __split_vma() bypasses sysctl_max_map_count checking. We use this where it * has already been checked or doesn't make sense to fail. */ -int __split_vma(struct mm_struct *mm, struct vm_area_struct *vma, +int __split_vma(struct vma_iterator *vmi, struct vm_area_struct *vma, unsigned long addr, int new_below) { struct vm_area_struct *new; int err; - validate_mm_mt(mm); + unsigned long end = vma->vm_end; + + validate_mm_mt(vma->vm_mm); if (vma->vm_ops && vma->vm_ops->may_split) { err = vma->vm_ops->may_split(vma, addr); @@ -2273,8 +2260,10 @@ int __split_vma(struct mm_struct *mm, struct vm_area_struct *vma, err = vma_adjust(vma, vma->vm_start, addr, vma->vm_pgoff, new); /* Success. */ - if (!err) + if (!err) { + vma_iter_set(vmi, end); return 0; + } /* Avoid vm accounting in close() operation */ new->vm_start = new->vm_end; @@ -2289,46 +2278,21 @@ 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); + validate_mm_mt(vma->vm_mm); return err; } -int vmi__split_vma(struct vma_iterator *vmi, struct mm_struct *mm, - struct vm_area_struct *vma, unsigned long addr, int new_below) -{ - int ret; - unsigned long end = vma->vm_end; - - ret = __split_vma(mm, vma, addr, new_below); - if (!ret) - vma_iter_set(vmi, end); - - return ret; -} /* * Split a vma into two pieces at address 'addr', a new vma is allocated * either for the first part or the tail. */ -int split_vma(struct mm_struct *mm, struct vm_area_struct *vma, +int split_vma(struct vma_iterator *vmi, struct vm_area_struct *vma, unsigned long addr, int new_below) { - if (mm->map_count >= sysctl_max_map_count) + if (vma->vm_mm->map_count >= sysctl_max_map_count) return -ENOMEM; - return __split_vma(mm, vma, addr, new_below); -} - -int vmi_split_vma(struct vma_iterator *vmi, struct mm_struct *mm, - struct vm_area_struct *vma, unsigned long addr, int new_below) -{ - int ret; - unsigned long end = vma->vm_end; - - ret = split_vma(mm, vma, addr, new_below); - if (!ret) - vma_iter_set(vmi, end); - - return ret; + return __split_vma(vmi, vma, addr, new_below); } static inline int munmap_sidetree(struct vm_area_struct *vma, @@ -2388,7 +2352,7 @@ do_vmi_align_munmap(struct vma_iterator *vmi, struct vm_area_struct *vma, if (end < vma->vm_end && mm->map_count >= sysctl_max_map_count) goto map_count_exceeded; - error = vmi__split_vma(vmi, mm, vma, start, 0); + error = __split_vma(vmi, vma, start, 0); if (error) goto start_split_failed; @@ -2409,7 +2373,7 @@ do_vmi_align_munmap(struct vma_iterator *vmi, struct vm_area_struct *vma, if (next->vm_end > end) { struct vm_area_struct *split; - error = vmi__split_vma(vmi, mm, next, end, 1); + error = __split_vma(vmi, next, end, 1); if (error) goto end_split_failed; @@ -2690,9 +2654,10 @@ cannot_expand: * vma again as we may succeed this time. */ if (unlikely(vm_flags != vma->vm_flags && prev)) { - merge = vmi_vma_merge(&vmi, mm, prev, vma->vm_start, - vma->vm_end, vma->vm_flags, NULL, vma->vm_file, - vma->vm_pgoff, NULL, NULL_VM_UFFD_CTX, NULL); + merge = vma_merge(&vmi, mm, prev, vma->vm_start, + vma->vm_end, vma->vm_flags, NULL, + vma->vm_file, vma->vm_pgoff, NULL, + NULL_VM_UFFD_CTX, NULL); if (merge) { /* * ->mmap() can change vma->vm_file and fput @@ -3249,7 +3214,7 @@ struct vm_area_struct *copy_vma(struct vm_area_struct **vmap, if (new_vma && new_vma->vm_start < addr + len) return NULL; /* should never get here */ - new_vma = vmi_vma_merge(&vmi, mm, prev, addr, addr + len, vma->vm_flags, + new_vma = vma_merge(&vmi, 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)); if (new_vma) { -- cgit v1.2.3