diff options
author | Bernd Schubert <bschubert@ddn.com> | 2023-12-12 16:33:23 +0300 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-04-03 16:32:06 +0300 |
commit | 896f9ef9f06d121b0b0f8bd65dcf09128d204216 (patch) | |
tree | 5e3dc59d1dd6bebe8c2a93142e1b551f519d9554 /fs/fuse/file.c | |
parent | cdd33d54e789d229d6d5007cbf3f53965ca1a5c6 (diff) | |
download | linux-896f9ef9f06d121b0b0f8bd65dcf09128d204216.tar.xz |
fuse: fix VM_MAYSHARE and direct_io_allow_mmap
[ Upstream commit 9511176bbaee0ac60ecc84e7b01cf5972a59ea17 ]
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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'fs/fuse/file.c')
-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)) |