From fc28724d67c90ff48b976e0687caf79993160bed Mon Sep 17 00:00:00 2001 From: Adam Manzanares Date: Tue, 22 May 2018 10:52:18 -0700 Subject: [PATCH] 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 Signed-off-by: Al Viro --- fs/aio.c | 2 +- include/linux/fs.h | 13 +++++++++++-- 2 files changed, 12 insertions(+), 3 deletions(-) diff --git a/fs/aio.c b/fs/aio.c index b850e92..33299ec 100644 --- a/fs/aio.c +++ b/fs/aio.c @@ -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); diff --git a/include/linux/fs.h b/include/linux/fs.h index 4b6045e..b432fc3 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -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)), }; } -- 2.7.4