From: Eric Van Hensbergen ericvh@kernel.org
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@vger.kernel.org Fixes: 1543b4c5071c ("fs/9p: remove writeback fid and fix per-file modes") Reported-by: Robert Schwebel r.schwebel@pengutronix.de Closes: 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 Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- 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); }