| Message ID | 20170326032128.32721-1-ebiggers3@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Sat, 2017-03-25 at 20:21 -0700, Eric Biggers wrote: > From: Eric Biggers <ebiggers@google.com> > > In do_dentry_open(), initialize the readahead state using ->f_mapping > instead of ->f_mapping->host->i_mapping. This is equivalent, even for > block device files; we don't need the extra indirection because > ->f_mapping already represents the data read/written by the file (which > for block device nodes is the underlying block device mapping). > > Signed-off-by: Eric Biggers <ebiggers@google.com> > --- > fs/open.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/fs/open.c b/fs/open.c > index 949cef29c3bb..32e19fda24d2 100644 > --- a/fs/open.c > +++ b/fs/open.c > @@ -763,7 +763,7 @@ static int do_dentry_open(struct file *f, > > f->f_flags &= ~(O_CREAT | O_EXCL | O_NOCTTY | O_TRUNC); > > - file_ra_state_init(&f->f_ra, f->f_mapping->host->i_mapping); > + file_ra_state_init(&f->f_ra, f->f_mapping); > > return 0; > (cc'ing David Howells...) Yeah, that certainly looks circular to me. I was chatting with David the other day, and I asked him a similar question: When is f_mapping set to anything else other than what this would point to? filp->f_path.dentry->d_inode->i_mapping It seems like we might not need f_mapping at all, though David seemed to think that coda might sometimes set it to something different. Do you have any insight there? In any case: Reviewed-by: Jeff Layton <jlayton@redhat.com>
diff --git a/fs/open.c b/fs/open.c index 949cef29c3bb..32e19fda24d2 100644 --- a/fs/open.c +++ b/fs/open.c @@ -763,7 +763,7 @@ static int do_dentry_open(struct file *f, f->f_flags &= ~(O_CREAT | O_EXCL | O_NOCTTY | O_TRUNC); - file_ra_state_init(&f->f_ra, f->f_mapping->host->i_mapping); + file_ra_state_init(&f->f_ra, f->f_mapping); return 0;