diff options
| author | Mike Rapoport (Microsoft) <rppt@kernel.org> | 2026-04-02 07:11:52 +0300 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2026-04-18 00:10:54 -0700 |
| commit | 6ab703034f145ef8e1a705b1630cc317ec8dd8a2 (patch) | |
| tree | 97ef4c2d1db959ca6c0d45365e09aec4c6aed5b5 | |
| parent | f74991b4e3836dd38f3adb41b146994b283942a1 (diff) | |
| download | linux-next-history-6ab703034f14.tar.gz | |
userfaultfd: mfill_atomic(): remove retry logic
Since __mfill_atomic_pte() handles the retry for both anonymous and shmem,
there is no need to retry copying the date from the userspace in the loop
in mfill_atomic().
Drop the retry logic from mfill_atomic().
[rppt@kernel.org: remove safety measure of not returning ENOENT from _copy]
Link: https://lore.kernel.org/ac5zcDUY8CFHr6Lw@kernel.org
Link: https://lore.kernel.org/20260402041156.1377214-12-rppt@kernel.org
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Andrei Vagin <avagin@google.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: David Hildenbrand (Arm) <david@kernel.org>
Cc: Harry Yoo <harry.yoo@oracle.com>
Cc: Harry Yoo (Oracle) <harry@kernel.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: James Houghton <jthoughton@google.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Lorenzo Stoakes (Oracle) <ljs@kernel.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Nikita Kalyazin <kalyazin@amazon.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Sean Christopherson <seanjc@google.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: David Carlier <devnexen@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
| -rw-r--r-- | mm/userfaultfd.c | 27 |
1 files changed, 0 insertions, 27 deletions
diff --git a/mm/userfaultfd.c b/mm/userfaultfd.c index 8a023d9326c25..885da1e564665 100644 --- a/mm/userfaultfd.c +++ b/mm/userfaultfd.c @@ -29,7 +29,6 @@ struct mfill_state { struct vm_area_struct *vma; unsigned long src_addr; unsigned long dst_addr; - struct folio *folio; pmd_t *pmd; }; @@ -531,9 +530,6 @@ err_filemap_remove: ops->filemap_remove(folio, state->vma); err_folio_put: folio_put(folio); - /* Don't return -ENOENT so that our caller won't retry */ - if (ret == -ENOENT) - ret = -EFAULT; return ret; } @@ -899,7 +895,6 @@ static __always_inline ssize_t mfill_atomic(struct userfaultfd_ctx *ctx, VM_WARN_ON_ONCE(src_start + len <= src_start); VM_WARN_ON_ONCE(dst_start + len <= dst_start); -retry: err = mfill_get_vma(&state); if (err) goto out; @@ -926,26 +921,6 @@ retry: err = mfill_atomic_pte(&state); cond_resched(); - if (unlikely(err == -ENOENT)) { - void *kaddr; - - mfill_put_vma(&state); - VM_WARN_ON_ONCE(!state.folio); - - kaddr = kmap_local_folio(state.folio, 0); - err = copy_from_user(kaddr, - (const void __user *)state.src_addr, - PAGE_SIZE); - kunmap_local(kaddr); - if (unlikely(err)) { - err = -EFAULT; - goto out; - } - flush_dcache_folio(state.folio); - goto retry; - } else - VM_WARN_ON_ONCE(state.folio); - if (!err) { state.dst_addr += PAGE_SIZE; state.src_addr += PAGE_SIZE; @@ -960,8 +935,6 @@ retry: mfill_put_vma(&state); out: - if (state.folio) - folio_put(state.folio); VM_WARN_ON_ONCE(copied < 0); VM_WARN_ON_ONCE(err > 0); VM_WARN_ON_ONCE(!copied && !err); |