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 <Liam.Howlett@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/fs/userfaultfd.c b/fs/userfaultfd.c
index 4334bd3..f3c75c6 100644 (file)
--- a/fs/userfaultfd.c
+++ b/fs/userfaultfd.c
@@ -909,7 +909,7 @@ static int userfaultfd_release(struct inode *inode, struct file *file)
                        continue;
                }
                new_flags = vma->vm_flags & ~__VM_UFFD_FLAGS;
-               prev = vmi_vma_merge(&vmi, mm, prev, vma->vm_start, vma->vm_end,
+               prev = vma_merge(&vmi, mm, prev, vma->vm_start, vma->vm_end,
                                 new_flags, vma->anon_vma,
                                 vma->vm_file, vma->vm_pgoff,
                                 vma_policy(vma),
@@ -1452,7 +1452,7 @@ static int userfaultfd_register(struct userfaultfd_ctx *ctx,
                vma_end = min(end, vma->vm_end);
 
                new_flags = (vma->vm_flags & ~__VM_UFFD_FLAGS) | vm_flags;
-               prev = vmi_vma_merge(&vmi, mm, prev, start, vma_end, new_flags,
+               prev = vma_merge(&vmi, mm, prev, start, vma_end, new_flags,
                                 vma->anon_vma, vma->vm_file, vma->vm_pgoff,
                                 vma_policy(vma),
                                 ((struct vm_userfaultfd_ctx){ ctx }),
@@ -1463,12 +1463,12 @@ static int userfaultfd_register(struct userfaultfd_ctx *ctx,
                        goto next;
                }
                if (vma->vm_start < start) {
-                       ret = vmi_split_vma(&vmi, mm, vma, start, 1);
+                       ret = split_vma(&vmi, vma, start, 1);
                        if (ret)
                                break;
                }
                if (vma->vm_end > end) {
-                       ret = vmi_split_vma(&vmi, mm, vma, end, 0);
+                       ret = split_vma(&vmi, vma, end, 0);
                        if (ret)
                                break;
                }
@@ -1632,7 +1632,7 @@ static int userfaultfd_unregister(struct userfaultfd_ctx *ctx,
                        uffd_wp_range(mm, vma, start, vma_end - start, false);
 
                new_flags = vma->vm_flags & ~__VM_UFFD_FLAGS;
-               prev = vmi_vma_merge(&vmi, mm, prev, start, vma_end, new_flags,
+               prev = vma_merge(&vmi, mm, prev, start, vma_end, new_flags,
                                 vma->anon_vma, vma->vm_file, vma->vm_pgoff,
                                 vma_policy(vma),
                                 NULL_VM_UFFD_CTX, anon_vma_name(vma));
@@ -1641,12 +1641,12 @@ static int userfaultfd_unregister(struct userfaultfd_ctx *ctx,
                        goto next;
                }
                if (vma->vm_start < start) {
-                       ret = vmi_split_vma(&vmi, mm, vma, start, 1);
+                       ret = split_vma(&vmi, vma, start, 1);
                        if (ret)
                                break;
                }
                if (vma->vm_end > end) {
-                       ret = vmi_split_vma(&vmi, mm, vma, end, 0);
+                       ret = split_vma(&vmi, vma, end, 0);
                        if (ret)
                                break;
                }

diff --git a/include/linux/mm.h b/include/linux/mm.h
index 144ddfd..f3b49fe 100644 (file)
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -2839,24 +2839,16 @@ static inline int vma_adjust(struct vm_area_struct *vma, unsigned long start,
 {
        return __vma_adjust(vma, start, end, pgoff, insert, NULL);
 }
-extern struct vm_area_struct *vma_merge(struct mm_struct *,
-       struct vm_area_struct *prev, unsigned long addr, unsigned long end,
-       unsigned long vm_flags, struct anon_vma *, struct file *, pgoff_t,
-       struct mempolicy *, struct vm_userfaultfd_ctx, struct anon_vma_name *);
-extern struct vm_area_struct *vmi_vma_merge(struct vma_iterator *vmi,
+extern struct vm_area_struct *vma_merge(struct vma_iterator *vmi,
        struct mm_struct *, struct vm_area_struct *prev, unsigned long addr,
        unsigned long end, unsigned long vm_flags, struct anon_vma *,
        struct file *, pgoff_t, struct mempolicy *, struct vm_userfaultfd_ctx,
        struct anon_vma_name *);
 extern struct anon_vma *find_mergeable_anon_vma(struct vm_area_struct *);
-extern int __split_vma(struct mm_struct *, struct vm_area_struct *,
-                              unsigned long addr, int new_below);
-extern int vmi__split_vma(struct vma_iterator *vmi, struct mm_struct *,
-       struct vm_area_struct *, unsigned long addr, int new_below);
-extern int split_vma(struct mm_struct *, struct vm_area_struct *,
-       unsigned long addr, int new_below);
-extern int vmi_split_vma(struct vma_iterator *vmi, struct mm_struct *,
-               struct vm_area_struct *, unsigned long addr, int new_below);
+extern int __split_vma(struct vma_iterator *vmi, struct vm_area_struct *,
+                      unsigned long addr, int new_below);
+extern int split_vma(struct vma_iterator *vmi, struct vm_area_struct *,
+                        unsigned long addr, int new_below);
 extern int insert_vm_struct(struct mm_struct *, struct vm_area_struct *);
 extern void unlink_file_vma(struct vm_area_struct *);
 extern struct vm_area_struct *copy_vma(struct vm_area_struct **,

diff --git a/mm/madvise.c b/mm/madvise.c
index 4d44719..02b3177 100644 (file)
--- a/mm/madvise.c
+++ b/mm/madvise.c
@@ -150,7 +150,7 @@ static int madvise_update_vma(struct vm_area_struct *vma,
        }
 
        pgoff = vma->vm_pgoff + ((start - vma->vm_start) >> PAGE_SHIFT);
-       *prev = vmi_vma_merge(&vmi, mm, *prev, start, end, new_flags,
+       *prev = vma_merge(&vmi, mm, *prev, start, end, new_flags,
                          vma->anon_vma, vma->vm_file, pgoff, vma_policy(vma),
                          vma->vm_userfaultfd_ctx, anon_name);
        if (*prev) {
@@ -163,7 +163,7 @@ static int madvise_update_vma(struct vm_area_struct *vma,
        if (start != vma->vm_start) {
                if (unlikely(mm->map_count >= sysctl_max_map_count))
                        return -ENOMEM;
-               error = vmi__split_vma(&vmi, mm, vma, start, 1);
+               error = __split_vma(&vmi, vma, start, 1);
                if (error)
                        return error;
        }
@@ -171,7 +171,7 @@ static int madvise_update_vma(struct vm_area_struct *vma,
        if (end != vma->vm_end) {
                if (unlikely(mm->map_count >= sysctl_max_map_count))
                        return -ENOMEM;
-               error = vmi__split_vma(&vmi, mm, vma, end, 0);
+               error = __split_vma(&vmi, vma, end, 0);
                if (error)
                        return error;
        }

diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index ed68bdf..dd5ca94 100644 (file)
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -810,7 +810,7 @@ static int mbind_range(struct mm_struct *mm, unsigned long start,
 
                pgoff = vma->vm_pgoff +
                        ((vmstart - vma->vm_start) >> PAGE_SHIFT);
-               prev = vmi_vma_merge(&vmi, mm, prev, vmstart, vmend, vma->vm_flags,
+               prev = vma_merge(&vmi, mm, prev, vmstart, vmend, vma->vm_flags,
                                 vma->anon_vma, vma->vm_file, pgoff,
                                 new_pol, vma->vm_userfaultfd_ctx,
                                 anon_vma_name(vma));
@@ -819,12 +819,12 @@ static int mbind_range(struct mm_struct *mm, unsigned long start,
                        goto replace;
                }
                if (vma->vm_start != vmstart) {
-                       err = vmi_split_vma(&vmi, vma->vm_mm, vma, vmstart, 1);
+                       err = split_vma(&vmi, vma, vmstart, 1);
                        if (err)
                                goto out;
                }
                if (vma->vm_end != vmend) {
-                       err = vmi_split_vma(&vmi, vma->vm_mm, vma, vmend, 0);
+                       err = split_vma(&vmi, vma, vmend, 0);
                        if (err)
                                goto out;
                }

diff --git a/mm/mlock.c b/mm/mlock.c
index 0d09b90..0336f52 100644 (file)
--- a/mm/mlock.c
+++ b/mm/mlock.c
@@ -418,7 +418,7 @@ static int mlock_fixup(struct vma_iterator *vmi, struct vm_area_struct *vma,
                goto out;
 
        pgoff = vma->vm_pgoff + ((start - vma->vm_start) >> PAGE_SHIFT);
-       *prev = vmi_vma_merge(vmi, mm, *prev, start, end, newflags,
+       *prev = vma_merge(vmi, mm, *prev, start, end, newflags,
                        vma->anon_vma, vma->vm_file, pgoff, vma_policy(vma),
                        vma->vm_userfaultfd_ctx, anon_vma_name(vma));
        if (*prev) {
@@ -427,13 +427,13 @@ static int mlock_fixup(struct vma_iterator *vmi, struct vm_area_struct *vma,
        }
 
        if (start != vma->vm_start) {
-               ret = vmi_split_vma(vmi, mm, vma, start, 1);
+               ret = split_vma(vmi, vma, start, 1);
                if (ret)
                        goto out;
        }
 
        if (end != vma->vm_end) {
-               ret = vmi_split_vma(vmi, mm, vma, end, 0);
+               ret = split_vma(vmi, vma, end, 0);
                if (ret)
                        goto out;
        }

diff --git a/mm/mmap.c b/mm/mmap.c
index 8806bfb..afc65f1 100644 (file)
--- 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) {

diff --git a/mm/mprotect.c b/mm/mprotect.c
index 39b6335..cce6a0e 100644 (file)
--- a/mm/mprotect.c
+++ b/mm/mprotect.c
@@ -642,7 +642,7 @@ mprotect_fixup(struct vma_iterator *vmi, struct mmu_gather *tlb,
         * First try to merge with previous and/or next vma.
         */
        pgoff = vma->vm_pgoff + ((start - vma->vm_start) >> PAGE_SHIFT);
-       *pprev = vmi_vma_merge(vmi, mm, *pprev, start, end, newflags,
+       *pprev = vma_merge(vmi, mm, *pprev, start, end, newflags,
                           vma->anon_vma, vma->vm_file, pgoff, vma_policy(vma),
                           vma->vm_userfaultfd_ctx, anon_vma_name(vma));
        if (*pprev) {
@@ -654,13 +654,13 @@ mprotect_fixup(struct vma_iterator *vmi, struct mmu_gather *tlb,
        *pprev = vma;
 
        if (start != vma->vm_start) {
-               error = vmi_split_vma(vmi, mm, vma, start, 1);
+               error = split_vma(vmi, vma, start, 1);
                if (error)
                        goto fail;
        }
 
        if (end != vma->vm_end) {
-               error = vmi_split_vma(vmi, mm, vma, end, 0);
+               error = split_vma(vmi, vma, end, 0);
                if (error)
                        goto fail;
        }

diff --git a/mm/mremap.c b/mm/mremap.c
index f161516..71ba8ed 100644 (file)
--- a/mm/mremap.c
+++ b/mm/mremap.c
@@ -1043,12 +1043,10 @@ SYSCALL_DEFINE5(mremap, unsigned long, addr, unsigned long, old_len,
                         * when a vma would be actually removed due to a merge.
                         */
                        if (!vma->vm_ops || !vma->vm_ops->close) {
-                               vma = vmi_vma_merge(&vmi, mm, vma,
-                                      extension_start, extension_end,
-                                      vma->vm_flags, vma->anon_vma,
-                                      vma->vm_file, extension_pgoff,
-                                      vma_policy(vma), vma->vm_userfaultfd_ctx,
-                                      anon_vma_name(vma));
+                               vma = vma_merge(&vmi, mm, vma, extension_start,
+                                       extension_end, vma->vm_flags, vma->anon_vma,
+                                       vma->vm_file, extension_pgoff, vma_policy(vma),
+                                       vma->vm_userfaultfd_ctx, anon_vma_name(vma));
                        } else if (vma_adjust(vma, vma->vm_start, addr + new_len,
                                   vma->vm_pgoff, NULL)) {
                                vma = NULL;

diff --git a/mm/nommu.c b/mm/nommu.c
index 9ddeb92..9a16673 100644 (file)
--- a/mm/nommu.c
+++ b/mm/nommu.c
@@ -1297,18 +1297,20 @@ SYSCALL_DEFINE1(old_mmap, struct mmap_arg_struct __user *, arg)
  * split a vma into two pieces at address 'addr', a new vma is allocated either
  * for the first part or the tail.
  */
-int vmi_split_vma(struct vma_iterator *vmi, struct mm_struct *mm,
-                 struct vm_area_struct *vma, unsigned long addr, int new_below)
+int split_vma(struct vma_iterator *vmi, struct vm_area_struct *vma,
+             unsigned long addr, int new_below)
 {
        struct vm_area_struct *new;
        struct vm_region *region;
        unsigned long npages;
+       struct mm_struct *mm;
 
        /* we're only permitted to split anonymous regions (these should have
         * only a single usage on the region) */
        if (vma->vm_file)
                return -ENOMEM;
 
+       mm = vma->vm_mm;
        if (mm->map_count >= sysctl_max_map_count)
                return -ENOMEM;
 
@@ -1465,7 +1467,7 @@ int do_munmap(struct mm_struct *mm, unsigned long start, size_t len, struct list
                if (end != vma->vm_end && offset_in_page(end))
                        return -EINVAL;
                if (start != vma->vm_start && end != vma->vm_end) {
-                       ret = vmi_split_vma(&vmi, mm, vma, start, 1);
+                       ret = split_vma(&vmi, vma, start, 1);
                        if (ret < 0)
                                return ret;
                }