Re: [PATCH v4 6/6] io_uring: add support for zone-append
From: "hch@infradead.org" <hch@infradead.org>
Date: 2020-07-31 13:08:14
Also in:
io-uring, linux-block, linux-fsdevel, lkml
Subsystem:
aio, filesystems (vfs and infrastructure), the rest · Maintainers:
Benjamin LaHaise, Alexander Viro, Christian Brauner, Linus Torvalds
And FYI, this is what I'd do for a hacky aio-only prototype (untested):
diff --git a/fs/aio.c b/fs/aio.c
index 91e7cc4a9f179b..42b1934e38758b 100644
--- a/fs/aio.c
+++ b/fs/aio.c@@ -1438,7 +1438,10 @@ static void aio_complete_rw(struct kiocb *kiocb, long res, long res2) } iocb->ki_res.res = res; - iocb->ki_res.res2 = res2; + if ((kiocb->ki_flags & IOCB_REPORT_OFFSET) && res > 0) + iocb->ki_res.res2 = kiocb->ki_pos - res; + else + iocb->ki_res.res2 = res2; iocb_put(iocb); }
@@ -1452,6 +1455,8 @@ static int aio_prep_rw(struct kiocb *req, const struct iocb *iocb) req->ki_flags = iocb_flags(req->ki_filp); if (iocb->aio_flags & IOCB_FLAG_RESFD) req->ki_flags |= IOCB_EVENTFD; + if (iocb->aio_flags & IOCB_FLAG_REPORT_OFFSET) + req->ki_flags |= IOCB_REPORT_OFFSET; req->ki_hint = ki_hint_validate(file_write_hint(req->ki_filp)); if (iocb->aio_flags & IOCB_FLAG_IOPRIO) { /*
diff --git a/include/linux/fs.h b/include/linux/fs.h
index f5abba86107d86..522b0a3437d420 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h@@ -316,6 +316,7 @@ enum rw_hint { #define IOCB_WRITE (1 << 6) #define IOCB_NOWAIT (1 << 7) #define IOCB_NOIO (1 << 9) +#define IOCB_REPORT_OFFSET (1 << 10) struct kiocb { struct file *ki_filp;
diff --git a/include/uapi/linux/aio_abi.h b/include/uapi/linux/aio_abi.h
index 8387e0af0f768a..e4313d7aa3b7e7 100644
--- a/include/uapi/linux/aio_abi.h
+++ b/include/uapi/linux/aio_abi.h@@ -55,6 +55,7 @@ enum { */ #define IOCB_FLAG_RESFD (1 << 0) #define IOCB_FLAG_IOPRIO (1 << 1) +#define IOCB_FLAG_REPORT_OFFSET (1 << 2) /* read() from /dev/aio returns these structures. */ struct io_event {