This eliminates a check for shared that was overrestrictive and
duplicated a check in generic_file_readonly_mmap.

Fixes: 1543b4c5071c ("fs/9p: remove writeback fid and fix per-file modes")
Link: https://lore.kernel.org/v9fs/ZK25XZ%2BGpR3KHIB%2F@pengutronix.de/
Reviewed-by: Dominique Martinet <asmadeus@codewreck.org>
Reviewed-by: Christian Schoenebeck <linux_oss@crudebyte.com>
Signed-off-by: Eric Van Hensbergen <ericvh@kernel.org>
---
 fs/9p/vfs_file.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/fs/9p/vfs_file.c b/fs/9p/vfs_file.c
index 2996fb00387f..9b61b480a9b0 100644
--- a/fs/9p/vfs_file.c
+++ b/fs/9p/vfs_file.c
@@ -505,9 +505,7 @@ v9fs_file_mmap(struct file *filp, struct vm_area_struct *vma)
 	p9_debug(P9_DEBUG_MMAP, "filp :%p\n", filp);
 
 	if (!(v9ses->cache & CACHE_WRITEBACK)) {
-		p9_debug(P9_DEBUG_CACHE, "(no mmap mode)");
-		if (vma->vm_flags & VM_MAYSHARE)
-			return -ENODEV;
+		p9_debug(P9_DEBUG_CACHE, "(read-only mmap mode)");
 		invalidate_inode_pages2(filp->f_mapping);
 		return generic_file_readonly_mmap(filp, vma);
 	}

-- 
2.39.2

On Wed, Jul 19, 2023 at 03:17:05PM +0000, Eric Van Hensbergen wrote:
> This eliminates a check for shared that was overrestrictive and
> duplicated a check in generic_file_readonly_mmap.
> 
> Fixes: 1543b4c5071c ("fs/9p: remove writeback fid and fix per-file modes")
> Link: https://lore.kernel.org/v9fs/ZK25XZ%2BGpR3KHIB%2F@pengutronix.de/
> Reviewed-by: Dominique Martinet <asmadeus@codewreck.org>
> Reviewed-by: Christian Schoenebeck <linux_oss@crudebyte.com>
> Signed-off-by: Eric Van Hensbergen <ericvh@kernel.org>
> ---
>  fs/9p/vfs_file.c | 4 +---
>  1 file changed, 1 insertion(+), 3 deletions(-)

<formletter>

This is not the correct way to submit patches for inclusion in the
stable kernel tree.  Please read:
    https://www.kernel.org/doc/html/latest/process/stable-kernel-rules.html
for how to do this properly.

</formletter>