[Virtio-fs] [PATCH 2/2] virtiofsd: No need to promote O_WRONLY to O_RDWR

[Vivek Goyal]

I am not sure why do we still need this logic. mmap() needs file to be
opened for O_RDONLY atleast. And we open file either as O_RDONLY or
O_RDWR in lo_setupmapping() depending on if read-only or read-write
mapping is required.

So it should not matter how fd is opended during lo_create() or lo_open()
because we are not going to use that fd anyway for mmap().

So for now drop this logic. I ran pjdfstests and blogbench and both
ran successfully.

Signed-off-by: Vivek Goyal <vgoyal at redhat.com>
---
 contrib/virtiofsd/passthrough_ll.c | 12 ------------
 1 file changed, 12 deletions(-)

diff --git a/contrib/virtiofsd/passthrough_ll.c b/contrib/virtiofsd/passthrough_ll.c
index c09c46a7e5..502ce50178 100644
--- a/contrib/virtiofsd/passthrough_ll.c
+++ b/contrib/virtiofsd/passthrough_ll.c
@@ -1513,12 +1513,6 @@ static void lo_create(fuse_req_t req, fuse_ino_t parent, const char *name,
 	if (err)
 		goto out;
 
-	/* Promote O_WRONLY to O_RDWR. Otherwise later mmap(PROT_WRITE) fails */
-	if ((fi->flags & O_ACCMODE) == O_WRONLY) {
-		fi->flags &= ~O_ACCMODE;
-		fi->flags |= O_RDWR;
-	}
-
 	fd = openat(lo_fd(req, parent), name,
 		    (fi->flags | O_CREAT) & ~O_NOFOLLOW, mode);
 	err = fd == -1 ? errno : 0;
@@ -1710,12 +1704,6 @@ static void lo_open(fuse_req_t req, fuse_ino_t ino, struct fuse_file_info *fi)
 		fuse_debug("lo_open(ino=%" PRIu64 ", flags=%d)\n",
 			   ino, fi->flags);
 
-	/* Promote O_WRONLY to O_RDWR. Otherwise later mmap(PROT_WRITE) fails */
-	if ((fi->flags & O_ACCMODE) == O_WRONLY) {
-		fi->flags &= ~O_ACCMODE;
-		fi->flags |= O_RDWR;
-	}
-
 	/* With writeback cache, kernel may send read requests even
 	   when userspace opened write-only */
 	if (lo->writeback && (fi->flags & O_ACCMODE) == O_WRONLY) {
-- 
2.17.2