diff options
| author | Matthew Wilcox (Oracle) <willy@infradead.org> | 2023-07-24 19:54:02 +0100 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2023-08-18 10:12:51 -0700 |
| commit | 350f6bbca1de515cd7519a33661cefc93ea06054 (patch) | |
| tree | 097b836f7ea8c5145eae8c2c37dcee42591d148a /net | |
| parent | 284e05920498788c5df1a7dd6424adb426498e1c (diff) | |
mm: allow per-VMA locks on file-backed VMAs
Remove the TCP layering violation by allowing per-VMA locks on all VMAs.
The fault path will immediately fail in handle_mm_fault(). There may be a
small performance reduction from this patch as a little unnecessary work
will be done on each page fault. See later patches for the improvement.
Link: https://lkml.kernel.org/r/20230724185410.1124082-3-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Cc: Arjun Roy <arjunroy@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Punit Agrawal <punit.agrawal@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'net')
| -rw-r--r-- | net/ipv4/tcp.c | 11 |
1 files changed, 4 insertions, 7 deletions
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 8ed52e1e3c99..b9d49803e77f 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -1739,7 +1739,7 @@ void tcp_update_recv_tstamps(struct sk_buff *skb, } #ifdef CONFIG_MMU -const struct vm_operations_struct tcp_vm_ops = { +static const struct vm_operations_struct tcp_vm_ops = { }; int tcp_mmap(struct file *file, struct socket *sock, @@ -2042,13 +2042,10 @@ static struct vm_area_struct *find_tcp_vma(struct mm_struct *mm, unsigned long address, bool *mmap_locked) { - struct vm_area_struct *vma = NULL; + struct vm_area_struct *vma = lock_vma_under_rcu(mm, address); -#ifdef CONFIG_PER_VMA_LOCK - vma = lock_vma_under_rcu(mm, address); -#endif if (vma) { - if (!vma_is_tcp(vma)) { + if (vma->vm_ops != &tcp_vm_ops) { vma_end_read(vma); return NULL; } @@ -2058,7 +2055,7 @@ static struct vm_area_struct *find_tcp_vma(struct mm_struct *mm, mmap_read_lock(mm); vma = vma_lookup(mm, address); - if (!vma || !vma_is_tcp(vma)) { + if (!vma || vma->vm_ops != &tcp_vm_ops) { mmap_read_unlock(mm); return NULL; } |