| Message ID | 1456160876-14560-5-git-send-email-hch@lst.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Christoph Hellwig <hch@lst.de> writes: > This adds a flag that tells the file system that this is a high priority > request for which it's worth to poll the hardware. The flag is purely > advisory and can be ignored if not supported. I'm not in love with the HIGHPRI name, but I don't have a better one in mind. So... Acked-by: Jeff Moyer <jmoyer@redhat.com> > > Signed-off-by: Christoph Hellwig <hch@lst.de> > --- > fs/read_write.c | 6 ++++-- > include/linux/fs.h | 1 + > include/uapi/linux/fs.h | 3 +++ > 3 files changed, 8 insertions(+), 2 deletions(-) > > diff --git a/fs/read_write.c b/fs/read_write.c > index 38b9afa..3b3fb22 100644 > --- a/fs/read_write.c > +++ b/fs/read_write.c > @@ -697,10 +697,12 @@ static ssize_t do_iter_readv_writev(struct file *filp, struct iov_iter *iter, > struct kiocb kiocb; > ssize_t ret; > > - if (flags) > + if (flags & ~RWF_HIPRI) > return -EOPNOTSUPP; > > init_sync_kiocb(&kiocb, filp); > + if (flags & RWF_HIPRI) > + kiocb.ki_flags |= IOCB_HIPRI; > kiocb.ki_pos = *ppos; > > ret = fn(&kiocb, iter); > @@ -715,7 +717,7 @@ static ssize_t do_loop_readv_writev(struct file *filp, struct iov_iter *iter, > { > ssize_t ret = 0; > > - if (flags) > + if (flags & ~RWF_HIPRI) > return -EOPNOTSUPP; > > while (iov_iter_count(iter)) { > diff --git a/include/linux/fs.h b/include/linux/fs.h > index 875277a..a1f731c 100644 > --- a/include/linux/fs.h > +++ b/include/linux/fs.h > @@ -320,6 +320,7 @@ struct writeback_control; > #define IOCB_EVENTFD (1 << 0) > #define IOCB_APPEND (1 << 1) > #define IOCB_DIRECT (1 << 2) > +#define IOCB_HIPRI (1 << 3) > > struct kiocb { > struct file *ki_filp; > diff --git a/include/uapi/linux/fs.h b/include/uapi/linux/fs.h > index 149bec8..d246339 100644 > --- a/include/uapi/linux/fs.h > +++ b/include/uapi/linux/fs.h > @@ -304,4 +304,7 @@ struct fsxattr { > #define SYNC_FILE_RANGE_WRITE 2 > #define SYNC_FILE_RANGE_WAIT_AFTER 4 > > +/* flags for preadv2/pwritev2: */ > +#define RWF_HIPRI 0x00000001 /* high priority request, poll if possible */ > + > #endif /* _UAPI_LINUX_FS_H */ -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Fri, Feb 26, 2016 at 04:56:03PM -0500, Jeff Moyer wrote: > Christoph Hellwig <hch@lst.de> writes: > > > This adds a flag that tells the file system that this is a high priority > > request for which it's worth to poll the hardware. The flag is purely > > advisory and can be ignored if not supported. > > I'm not in love with the HIGHPRI name, but I don't have a better one in > mind. So... I don't really like it too much either. So if someone else has a better suggestion: you're welcome! -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/fs/read_write.c b/fs/read_write.c index 38b9afa..3b3fb22 100644 --- a/fs/read_write.c +++ b/fs/read_write.c @@ -697,10 +697,12 @@ static ssize_t do_iter_readv_writev(struct file *filp, struct iov_iter *iter, struct kiocb kiocb; ssize_t ret; - if (flags) + if (flags & ~RWF_HIPRI) return -EOPNOTSUPP; init_sync_kiocb(&kiocb, filp); + if (flags & RWF_HIPRI) + kiocb.ki_flags |= IOCB_HIPRI; kiocb.ki_pos = *ppos; ret = fn(&kiocb, iter); @@ -715,7 +717,7 @@ static ssize_t do_loop_readv_writev(struct file *filp, struct iov_iter *iter, { ssize_t ret = 0; - if (flags) + if (flags & ~RWF_HIPRI) return -EOPNOTSUPP; while (iov_iter_count(iter)) { diff --git a/include/linux/fs.h b/include/linux/fs.h index 875277a..a1f731c 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -320,6 +320,7 @@ struct writeback_control; #define IOCB_EVENTFD (1 << 0) #define IOCB_APPEND (1 << 1) #define IOCB_DIRECT (1 << 2) +#define IOCB_HIPRI (1 << 3) struct kiocb { struct file *ki_filp; diff --git a/include/uapi/linux/fs.h b/include/uapi/linux/fs.h index 149bec8..d246339 100644 --- a/include/uapi/linux/fs.h +++ b/include/uapi/linux/fs.h @@ -304,4 +304,7 @@ struct fsxattr { #define SYNC_FILE_RANGE_WRITE 2 #define SYNC_FILE_RANGE_WAIT_AFTER 4 +/* flags for preadv2/pwritev2: */ +#define RWF_HIPRI 0x00000001 /* high priority request, poll if possible */ + #endif /* _UAPI_LINUX_FS_H */
This adds a flag that tells the file system that this is a high priority request for which it's worth to poll the hardware. The flag is purely advisory and can be ignored if not supported. Signed-off-by: Christoph Hellwig <hch@lst.de> --- fs/read_write.c | 6 ++++-- include/linux/fs.h | 1 + include/uapi/linux/fs.h | 3 +++ 3 files changed, 8 insertions(+), 2 deletions(-)