On 9/20/2022 12:32 AM, Ronnie Sahlberg wrote:
This is the opposite case of kernel bugzilla 216301. If we mmap a file using cache=none and then proceed to update the mmapped area these updates are not reflected in a later pread() of that part of the file. To fix this we must first destage any dirty pages in the range before we allow the pread() to proceed.
Cc: stable@vger.kernel.org Reviewed-by: Paulo Alcantara (SUSE) pc@cjr.nz Reviewed-by: Enzo Matsumiya ematsumiya@suse.de Signed-off-by: Ronnie Sahlberg lsahlber@redhat.com
fs/cifs/file.c | 9 +++++++++ 1 file changed, 9 insertions(+)
diff --git a/fs/cifs/file.c b/fs/cifs/file.c index 6f38b134a346..7d756721e1a6 100644 --- a/fs/cifs/file.c +++ b/fs/cifs/file.c @@ -4271,6 +4271,15 @@ static ssize_t __cifs_readv( len = ctx->len; }
- if (direct) {
rc = filemap_write_and_wait_range(file->f_inode->i_mapping,offset, offset + len - 1);
It's only a nit, but with the new EAGAIN return code below, it's no longer necessary to capture "rc" here.
if (rc) {kref_put(&ctx->refcount, cifs_aio_ctx_release);return -EAGAIN;}- }
- /* grab a lock here due to read response handlers can access ctx */ mutex_lock(&ctx->aio_mutex);