aio: Kill ki_users

The kiocb refcount is only needed for cancellation - to ensure a kiocb
isn't freed while a ki_cancel callback is running. But if we restrict
ki_cancel callbacks to not block (which they currently don't), we can
simply drop the refcount.

Signed-off-by: Kent Overstreet <koverstreet@google.com>
Cc: Zach Brown <zab@redhat.com>
Cc: Felipe Balbi <balbi@ti.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Asai Thambi S P <asamymuthupa@micron.com>
Cc: Selvan Mani <smani@micron.com>
Cc: Sam Bradshaw <sbradshaw@micron.com>
Cc: Jeff Moyer <jmoyer@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Benjamin LaHaise <bcrl@kvack.org>
Cc: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Benjamin LaHaise <bcrl@kvack.org>
This commit is contained in:
Kent Overstreet 2013-05-13 13:42:52 -07:00 committed by Benjamin LaHaise
parent 8bc92afcf7
commit 57282d8fd7
2 changed files with 12 additions and 40 deletions

View file

@ -30,8 +30,6 @@ struct kiocb;
typedef int (kiocb_cancel_fn)(struct kiocb *);
struct kiocb {
atomic_t ki_users;
struct file *ki_filp;
struct kioctx *ki_ctx; /* NULL for sync ops */
kiocb_cancel_fn *ki_cancel;
@ -65,7 +63,6 @@ static inline bool is_sync_kiocb(struct kiocb *kiocb)
static inline void init_sync_kiocb(struct kiocb *kiocb, struct file *filp)
{
*kiocb = (struct kiocb) {
.ki_users = ATOMIC_INIT(1),
.ki_ctx = NULL,
.ki_filp = filp,
.ki_obj.tsk = current,
@ -75,7 +72,6 @@ static inline void init_sync_kiocb(struct kiocb *kiocb, struct file *filp)
/* prototypes */
#ifdef CONFIG_AIO
extern ssize_t wait_on_sync_kiocb(struct kiocb *iocb);
extern void aio_put_req(struct kiocb *iocb);
extern void aio_complete(struct kiocb *iocb, long res, long res2);
struct mm_struct;
extern void exit_aio(struct mm_struct *mm);
@ -84,7 +80,6 @@ extern long do_io_submit(aio_context_t ctx_id, long nr,
void kiocb_set_cancel_fn(struct kiocb *req, kiocb_cancel_fn *cancel);
#else
static inline ssize_t wait_on_sync_kiocb(struct kiocb *iocb) { return 0; }
static inline void aio_put_req(struct kiocb *iocb) { }
static inline void aio_complete(struct kiocb *iocb, long res, long res2) { }
struct mm_struct;
static inline void exit_aio(struct mm_struct *mm) { }