fs: Convert kiocb rw_hint from enum to u16

In order to avoid kiocb bloat for per command iopriority support, rw_hint
is converted from enum to a u16. Added a guard around ki_hint assignment.

Signed-off-by: Adam Manzanares <adam.manzanares@wdc.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Adam Manzanares 2018-05-22 10:52:18 -07:00 committed by Al Viro
parent aa43457799
commit fc28724d67
2 changed files with 12 additions and 3 deletions

View File

@ -1434,7 +1434,7 @@ static int aio_prep_rw(struct kiocb *req, struct iocb *iocb)
req->ki_flags = iocb_flags(req->ki_filp);
if (iocb->aio_flags & IOCB_FLAG_RESFD)
req->ki_flags |= IOCB_EVENTFD;
req->ki_hint = file_write_hint(req->ki_filp);
req->ki_hint = ki_hint_validate(file_write_hint(req->ki_filp));
ret = kiocb_set_rw_flags(req, iocb->aio_rw_flags);
if (unlikely(ret))
fput(req->ki_filp);

View File

@ -299,7 +299,7 @@ struct kiocb {
void (*ki_complete)(struct kiocb *iocb, long ret, long ret2);
void *private;
int ki_flags;
enum rw_hint ki_hint;
u16 ki_hint;
} __randomize_layout;
static inline bool is_sync_kiocb(struct kiocb *kiocb)
@ -1929,12 +1929,21 @@ static inline enum rw_hint file_write_hint(struct file *file)
static inline int iocb_flags(struct file *file);
static inline u16 ki_hint_validate(enum rw_hint hint)
{
typeof(((struct kiocb *)0)->ki_hint) max_hint = -1;
if (hint <= max_hint)
return hint;
return 0;
}
static inline void init_sync_kiocb(struct kiocb *kiocb, struct file *filp)
{
*kiocb = (struct kiocb) {
.ki_filp = filp,
.ki_flags = iocb_flags(filp),
.ki_hint = file_write_hint(filp),
.ki_hint = ki_hint_validate(file_write_hint(filp)),
};
}