From 3b87184f7eff27fef7d7ee18b65f173152e1bb81 Mon Sep 17 00:00:00 2001
From: Jens Axboe <axboe@kernel.dk>
Date: Sat, 15 Jun 2024 20:47:14 -0600
Subject: [PATCH] io_uring/advise: support 64-bit lengths
The existing fadvise/madvise support only supports 32-bit lengths. Add
support for 64-bit lengths, enabled by the application setting sqe->off
rather than sqe->len for the length. If sqe->len is set, then that is
used as the 32-bit length. If sqe->len is zero, then sqe->off is read
for full 64-bit support.
Older kernels will return -EINVAL if 64-bit support isn't available.
Fixes: 4840e418c2fc ("io_uring: add IORING_OP_FADVISE")
Fixes: c1ca757bd6f4 ("io_uring: add IORING_OP_MADVISE")
Reported-by: Stefan <source@s.muenzel.net>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
---
io_uring/advise.c | 16 ++++++++++------
1 file changed, 10 insertions(+), 6 deletions(-)
diff --git a/io_uring/advise.c b/io_uring/advise.c
index 7085804c513c0..cb7b881665e57 100644
--- a/io_uring/advise.c
+++ b/io_uring/advise.c
@@ -17,14 +17,14 @@
struct io_fadvise {
struct file *file;
u64 offset;
- u32 len;
+ u64 len;
u32 advice;
};
struct io_madvise {
struct file *file;
u64 addr;
- u32 len;
+ u64 len;
u32 advice;
};
@@ -33,11 +33,13 @@ int io_madvise_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
#if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU)
struct io_madvise *ma = io_kiocb_to_cmd(req, struct io_madvise);
- if (sqe->buf_index || sqe->off || sqe->splice_fd_in)
+ if (sqe->buf_index || sqe->splice_fd_in)
return -EINVAL;
ma->addr = READ_ONCE(sqe->addr);
- ma->len = READ_ONCE(sqe->len);
+ ma->len = READ_ONCE(sqe->off);
+ if (!ma->len)
+ ma->len = READ_ONCE(sqe->len);
ma->advice = READ_ONCE(sqe->fadvise_advice);
req->flags |= REQ_F_FORCE_ASYNC;
return 0;
@@ -78,11 +80,13 @@ int io_fadvise_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
{
struct io_fadvise *fa = io_kiocb_to_cmd(req, struct io_fadvise);
- if (sqe->buf_index || sqe->addr || sqe->splice_fd_in)
+ if (sqe->buf_index || sqe->splice_fd_in)
return -EINVAL;
fa->offset = READ_ONCE(sqe->off);
- fa->len = READ_ONCE(sqe->len);
+ fa->len = READ_ONCE(sqe->addr);
+ if (!fa->len)
+ fa->len = READ_ONCE(sqe->len);
fa->advice = READ_ONCE(sqe->fadvise_advice);
if (io_fadvise_force_async(fa))
req->flags |= REQ_F_FORCE_ASYNC;
--
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