mm/userfaultfd: Inline mfill_atomic() into poison operation and remove uffd_flags_t

The inline allows for the poison operation to know what uffd_ops to use
for the operation due to call path.  Drop the code that figures out
uffd_ops.

The uffd_flags_t existed to pass the operation data around and is no
longer used.

Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>

diff --git a/fs/userfaultfd.c b/fs/userfaultfd.c
index 972c6f75b5504f7c2768363eb0d578fb42c54945..449e39df003f41140668e8d7a93ff3df134f5a9a 100644 (file)
--- a/fs/userfaultfd.c
+++ b/fs/userfaultfd.c
@@ -1842,7 +1842,7 @@ static inline int userfaultfd_poison(struct userfaultfd_ctx *ctx, unsigned long
 
        if (mmget_not_zero(ctx->mm)) {
                ret = mfill_atomic_poison(ctx, uffdio_poison.range.start,
-                                         uffdio_poison.range.len, 0);
+                                         uffdio_poison.range.len);
                mmput(ctx->mm);
        } else {
                return -ESRCH;

diff --git a/include/linux/userfaultfd_k.h b/include/linux/userfaultfd_k.h
index 4154fad2af55ad73a410c83d86ad476a319eeb41..2c8b824ab4cccf1753ee746d80478315837c0208 100644 (file)
--- a/include/linux/userfaultfd_k.h
+++ b/include/linux/userfaultfd_k.h
@@ -80,9 +80,6 @@ struct userfaultfd_ctx {
 
 extern vm_fault_t handle_userfault(struct vm_fault *vmf, unsigned long reason);
 
-/* A combined operation mode + behavior flags. */
-typedef unsigned int __bitwise uffd_flags_t;
-
 /* Mutually exclusive modes of operation. */
 enum mfill_atomic_mode {
        MFILL_ATOMIC_COPY,
@@ -142,25 +139,6 @@ struct vm_uffd_ops {
        void (*complete_register)(struct vm_area_struct *vma);
 };
 
-#define MFILL_ATOMIC_MODE_BITS (const_ilog2(NR_MFILL_ATOMIC_MODES - 1) + 1)
-#define MFILL_ATOMIC_BIT(nr) BIT(MFILL_ATOMIC_MODE_BITS + (nr))
-#define MFILL_ATOMIC_FLAG(nr) ((__force uffd_flags_t) MFILL_ATOMIC_BIT(nr))
-#define MFILL_ATOMIC_MODE_MASK ((__force uffd_flags_t) (MFILL_ATOMIC_BIT(0) - 1))
-
-static inline bool uffd_flags_mode_is(uffd_flags_t flags, enum mfill_atomic_mode expected)
-{
-       return (flags & MFILL_ATOMIC_MODE_MASK) == ((__force uffd_flags_t) expected);
-}
-
-static inline uffd_flags_t uffd_flags_set_mode(uffd_flags_t flags, enum mfill_atomic_mode mode)
-{
-       flags &= ~MFILL_ATOMIC_MODE_MASK;
-       return flags | ((__force uffd_flags_t) mode);
-}
-
-/* Flags controlling behavior. These behavior changes are mode-independent. */
-#define MFILL_ATOMIC_WP MFILL_ATOMIC_FLAG(0)
-
 int mfill_atomic_install_pte(pmd_t *dst_pmd, struct vm_area_struct *dst_vma,
                unsigned long dst_addr, struct page *page,
                bool newly_allocated, bool wp);
@@ -171,8 +149,8 @@ ssize_t mfill_atomic_zeropage(struct userfaultfd_ctx *ctx,
                unsigned long dst_start, unsigned long len);
 ssize_t mfill_atomic_continue(struct userfaultfd_ctx *ctx,
                unsigned long dst_start, unsigned long len, bool wp);
-extern ssize_t mfill_atomic_poison(struct userfaultfd_ctx *ctx, unsigned long start,
-                                  unsigned long len, uffd_flags_t flags);
+ssize_t mfill_atomic_poison(struct userfaultfd_ctx *ctx, unsigned long start,
+               unsigned long len);
 extern int mwriteprotect_range(struct userfaultfd_ctx *ctx, unsigned long start,
                               unsigned long len, bool enable_wp);
 extern long uffd_wp_range(struct vm_area_struct *vma,

diff --git a/mm/userfaultfd.c b/mm/userfaultfd.c
index 0b4df148881120d6603b4d9f9f3a95aec982ad94..bf55556f2463ad5cd5e0faaaad756b7e1c288cb0 100644 (file)
--- a/mm/userfaultfd.c
+++ b/mm/userfaultfd.c
@@ -594,40 +594,6 @@ uffd_get_dst_pmd(struct vm_area_struct *dst_vma, unsigned long dst_addr,
        return 0;
 }
 
-static inline ssize_t uffd_info_set_ops(struct uffd_info *info,
-               uffd_flags_t flags)
-{
-       /*
-        * For shmem mappings, khugepaged is allowed to remove page
-        * tables under us; pte_offset_map_lock() will deal with that.
-        */
-       if (uffd_flags_mode_is(flags, MFILL_ATOMIC_POISON)) {
-               info->op = info->uffd_ops->poison;
-       } else if (uffd_flags_mode_is(flags, MFILL_ATOMIC_CONTINUE)) {
-               info->op = info->uffd_ops->cont;
-       } else if (uffd_flags_mode_is(flags, MFILL_ATOMIC_COPY)) {
-               info->op = info->uffd_ops->copy;
-               /*
-                * The normal page fault path for a shmem will invoke
-                * the fault, fill the hole in the file and COW it right
-                * away. The result generates plain anonymous memory. So
-                * when we are asked to fill an hole in a MAP_PRIVATE
-                * shmem mapping, we'll generate anonymous memory
-                * directly without actually filling the hole. For the
-                * MAP_PRIVATE case the robustness check only happens in
-                * the pagetable (to verify it's still none) and not in
-                * the radix tree.
-                */
-       } else {
-               info->op = info->uffd_ops->zeropage;
-       }
-
-       if (!info->op)
-               return -EINVAL;
-
-       return 0;
-}
-
 static inline ssize_t uffd_info_setup(struct uffd_info *info)
 {
 
@@ -710,36 +676,6 @@ out_unlock:
        return err;
 }
 
-static __always_inline ssize_t mfill_atomic(struct userfaultfd_ctx *ctx,
-                                           unsigned long dst_start,
-                                           unsigned long src_start,
-                                           unsigned long len,
-                                           uffd_flags_t flags)
-{
-       ssize_t err;
-       struct uffd_info info = UFFD_STRUCT_INIT(dst_start, src_start, len, ctx,
-                                                flags & MFILL_ATOMIC_WP);
-
-       mfill_atomic_validate(&info);
-       err = mfill_setup(&info);
-       if (err)
-               goto out;
-
-       err = uffd_info_set_ops(&info, flags);
-       if (err) {
-               uffd_ctx_unlock(&info);
-               goto out;
-       }
-
-       err = mfill_loop(&info);
-
-out:
-       VM_WARN_ON_ONCE(info.copied < 0);
-       VM_WARN_ON_ONCE(err > 0);
-       VM_WARN_ON_ONCE(!info.copied && !err);
-       return info.copied ? info.copied : err;
-}
-
 static __always_inline ssize_t mfill_copy_loop(struct uffd_info *info)
 {
        ssize_t err = -EINVAL;
@@ -853,11 +789,26 @@ out:
        return info.copied ? info.copied : err;
 }
 
-ssize_t mfill_atomic_poison(struct userfaultfd_ctx *ctx, unsigned long start,
-                           unsigned long len, uffd_flags_t flags)
+ssize_t mfill_atomic_poison(struct userfaultfd_ctx *ctx,
+               unsigned long dst_start, unsigned long len)
 {
-       return mfill_atomic(ctx, start, 0, len,
-                           uffd_flags_set_mode(flags, MFILL_ATOMIC_POISON));
+       ssize_t err;
+       struct uffd_info info = UFFD_STRUCT_INIT(dst_start, 0, len, ctx,
+                                                false);
+
+       mfill_atomic_validate(&info);
+       err = mfill_setup(&info);
+       if (err)
+               goto out;
+
+       info.op = info.uffd_ops->poison;
+       err = mfill_loop(&info);
+
+out:
+       VM_WARN_ON_ONCE(info.copied < 0);
+       VM_WARN_ON_ONCE(err > 0);
+       VM_WARN_ON_ONCE(!info.copied && !err);
+       return info.copied ? info.copied : err;
 }
 
 long uffd_wp_range(struct vm_area_struct *dst_vma,