| Message ID | 20230817141337.1025891-4-amir73il@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | kiocb_{start,end}_write() helpers | expand |
On Thu 17-08-23 17:13:33, Amir Goldstein wrote: > aio, io_uring, cachefiles and overlayfs, all open code an ugly variant > of file_{start,end}_write() to silence lockdep warnings. > > Create helpers for this lockdep dance so we can use the helpers in all > the callers. > > Suggested-by: Jan Kara <jack@suse.cz> > Signed-off-by: Amir Goldstein <amir73il@gmail.com> Looks good. Feel free to add: Reviewed-by: Jan Kara <jack@suse.cz> Honza > --- > include/linux/fs.h | 36 ++++++++++++++++++++++++++++++++++++ > 1 file changed, 36 insertions(+) > > diff --git a/include/linux/fs.h b/include/linux/fs.h > index ced388aff51f..2548048a6e6c 100644 > --- a/include/linux/fs.h > +++ b/include/linux/fs.h > @@ -2579,6 +2579,42 @@ static inline void file_end_write(struct file *file) > sb_end_write(file_inode(file)->i_sb); > } > > +/** > + * kiocb_start_write - get write access to a superblock for async file io > + * @iocb: the io context we want to submit the write with > + * > + * This is a variant of sb_start_write() for async io submission. > + * Should be matched with a call to kiocb_end_write(). > + */ > +static inline void kiocb_start_write(struct kiocb *iocb) > +{ > + struct inode *inode = file_inode(iocb->ki_filp); > + > + sb_start_write(inode->i_sb); > + /* > + * Fool lockdep by telling it the lock got released so that it > + * doesn't complain about the held lock when we return to userspace. > + */ > + __sb_writers_release(inode->i_sb, SB_FREEZE_WRITE); > +} > + > +/** > + * kiocb_end_write - drop write access to a superblock after async file io > + * @iocb: the io context we sumbitted the write with > + * > + * Should be matched with a call to kiocb_start_write(). > + */ > +static inline void kiocb_end_write(struct kiocb *iocb) > +{ > + struct inode *inode = file_inode(iocb->ki_filp); > + > + /* > + * Tell lockdep we inherited freeze protection from submission thread. > + */ > + __sb_writers_acquired(inode->i_sb, SB_FREEZE_WRITE); > + sb_end_write(inode->i_sb); > +} > + > /* > * This is used for regular files where some users -- especially the > * currently executed binary in a process, previously handled via > -- > 2.34.1 >
diff --git a/include/linux/fs.h b/include/linux/fs.h index ced388aff51f..2548048a6e6c 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -2579,6 +2579,42 @@ static inline void file_end_write(struct file *file) sb_end_write(file_inode(file)->i_sb); } +/** + * kiocb_start_write - get write access to a superblock for async file io + * @iocb: the io context we want to submit the write with + * + * This is a variant of sb_start_write() for async io submission. + * Should be matched with a call to kiocb_end_write(). + */ +static inline void kiocb_start_write(struct kiocb *iocb) +{ + struct inode *inode = file_inode(iocb->ki_filp); + + sb_start_write(inode->i_sb); + /* + * Fool lockdep by telling it the lock got released so that it + * doesn't complain about the held lock when we return to userspace. + */ + __sb_writers_release(inode->i_sb, SB_FREEZE_WRITE); +} + +/** + * kiocb_end_write - drop write access to a superblock after async file io + * @iocb: the io context we sumbitted the write with + * + * Should be matched with a call to kiocb_start_write(). + */ +static inline void kiocb_end_write(struct kiocb *iocb) +{ + struct inode *inode = file_inode(iocb->ki_filp); + + /* + * Tell lockdep we inherited freeze protection from submission thread. + */ + __sb_writers_acquired(inode->i_sb, SB_FREEZE_WRITE); + sb_end_write(inode->i_sb); +} + /* * This is used for regular files where some users -- especially the * currently executed binary in a process, previously handled via
aio, io_uring, cachefiles and overlayfs, all open code an ugly variant of file_{start,end}_write() to silence lockdep warnings. Create helpers for this lockdep dance so we can use the helpers in all the callers. Suggested-by: Jan Kara <jack@suse.cz> Signed-off-by: Amir Goldstein <amir73il@gmail.com> --- include/linux/fs.h | 36 ++++++++++++++++++++++++++++++++++++ 1 file changed, 36 insertions(+)