diff options
| author | Bernd Schubert <bschubert@ddn.com> | 2023-12-12 14:33:23 +0100 |
|---|---|---|
| committer | Miklos Szeredi <mszeredi@redhat.com> | 2024-02-23 17:36:31 +0100 |
| commit | 9511176bbaee0ac60ecc84e7b01cf5972a59ea17 (patch) | |
| tree | 1b8dbb28212210f73f5f6f6f8cffc83573ef8c7a /fs/fuse | |
| parent | 9086b2d9e9f3da0b0f939aa1d7ff74e9bf5b54c8 (diff) | |
fuse: fix VM_MAYSHARE and direct_io_allow_mmap
There were multiple issues with direct_io_allow_mmap:
- fuse_link_write_file() was missing, resulting in warnings in
fuse_write_file_get() and EIO from msync()
- "vma->vm_ops = &fuse_file_vm_ops" was not set, but especially
fuse_page_mkwrite is needed.
The semantics of invalidate_inode_pages2() is so far not clearly defined in
fuse_file_mmap. It dates back to commit 3121bfe76311 ("fuse: fix
"direct_io" private mmap") Though, as direct_io_allow_mmap is a new
feature, that was for MAP_PRIVATE only. As invalidate_inode_pages2() is
calling into fuse_launder_folio() and writes out dirty pages, it should be
safe to call invalidate_inode_pages2 for MAP_PRIVATE and MAP_SHARED as
well.
Cc: Hao Xu <howeyxu@tencent.com>
Cc: stable@vger.kernel.org
Fixes: e78662e818f9 ("fuse: add a new fuse init flag to relax restrictions in no cache mode")
Signed-off-by: Bernd Schubert <bschubert@ddn.com>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Diffstat (limited to 'fs/fuse')
| -rw-r--r-- | fs/fuse/file.c | 8 |
1 files changed, 6 insertions, 2 deletions
diff --git a/fs/fuse/file.c b/fs/fuse/file.c index 148a71b8b4d0..b9cff9b6ca1b 100644 --- a/fs/fuse/file.c +++ b/fs/fuse/file.c @@ -2468,7 +2468,8 @@ static int fuse_file_mmap(struct file *file, struct vm_area_struct *vma) return fuse_dax_mmap(file, vma); if (ff->open_flags & FOPEN_DIRECT_IO) { - /* Can't provide the coherency needed for MAP_SHARED + /* + * Can't provide the coherency needed for MAP_SHARED * if FUSE_DIRECT_IO_ALLOW_MMAP isn't set. */ if ((vma->vm_flags & VM_MAYSHARE) && !fc->direct_io_allow_mmap) @@ -2476,7 +2477,10 @@ static int fuse_file_mmap(struct file *file, struct vm_area_struct *vma) invalidate_inode_pages2(file->f_mapping); - return generic_file_mmap(file, vma); + if (!(vma->vm_flags & VM_MAYSHARE)) { + /* MAP_PRIVATE */ + return generic_file_mmap(file, vma); + } } if ((vma->vm_flags & VM_SHARED) && (vma->vm_flags & VM_MAYWRITE)) |