From: Eric Van Hensbergen <ericvh@xxxxxxxxxx>
commit 75b396821cb71164dac3a1ad51dda4781ea8dbad upstream.
This eliminates a check for shared that was overrestrictive and
prevented read-only mmaps when writeback caches weren't enabled.
Cc: stable@xxxxxxxxxxxxxxx
Fixes: 1543b4c5071c ("fs/9p: remove writeback fid and fix per-file modes")
Reported-by: Robert Schwebel <r.schwebel@xxxxxxxxxxxxxx>
Closes: https://lore.kernel.org/v9fs/ZK25XZ%2BGpR3KHIB%2F@xxxxxxxxxxxxxx
Reviewed-by: Dominique Martinet <asmadeus@xxxxxxxxxxxxx>
Reviewed-by: Christian Schoenebeck <linux_oss@xxxxxxxxxxxxx>
Signed-off-by: Eric Van Hensbergen <ericvh@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/9p/vfs_file.c | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)
--- a/fs/9p/vfs_file.c
+++ b/fs/9p/vfs_file.c
@@ -483,9 +483,7 @@ v9fs_file_mmap(struct file *filp, struct
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);
}
