io_uring/rw: add separate prep handler for fixed read/write

Rather than sprinkle opcode checks in the generic read/write prep handler,
have a separate prep handler for the vectored readv/writev operation.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Jens Axboe 2023-11-06 07:43:16 -07:00
parent 0e984ec88d
commit f688944cfb
3 changed files with 21 additions and 14 deletions

View File

@ -98,7 +98,7 @@ const struct io_issue_def io_issue_defs[] = {
.ioprio = 1,
.iopoll = 1,
.iopoll_queue = 1,
.prep = io_prep_rw,
.prep = io_prep_rw_fixed,
.issue = io_read,
},
[IORING_OP_WRITE_FIXED] = {
@ -111,7 +111,7 @@ const struct io_issue_def io_issue_defs[] = {
.ioprio = 1,
.iopoll = 1,
.iopoll_queue = 1,
.prep = io_prep_rw,
.prep = io_prep_rw_fixed,
.issue = io_write,
},
[IORING_OP_POLL_ADD] = {

View File

@ -83,18 +83,6 @@ int io_prep_rw(struct io_kiocb *req, const struct io_uring_sqe *sqe)
/* used for fixed read/write too - just read unconditionally */
req->buf_index = READ_ONCE(sqe->buf_index);
if (req->opcode == IORING_OP_READ_FIXED ||
req->opcode == IORING_OP_WRITE_FIXED) {
struct io_ring_ctx *ctx = req->ctx;
u16 index;
if (unlikely(req->buf_index >= ctx->nr_user_bufs))
return -EFAULT;
index = array_index_nospec(req->buf_index, ctx->nr_user_bufs);
req->imu = ctx->user_bufs[index];
io_req_set_rsrc_node(req, ctx, 0);
}
ioprio = READ_ONCE(sqe->ioprio);
if (ioprio) {
ret = ioprio_check_cap(ioprio);
@ -131,6 +119,24 @@ int io_prep_rwv(struct io_kiocb *req, const struct io_uring_sqe *sqe)
return 0;
}
int io_prep_rw_fixed(struct io_kiocb *req, const struct io_uring_sqe *sqe)
{
struct io_ring_ctx *ctx = req->ctx;
u16 index;
int ret;
ret = io_prep_rw(req, sqe);
if (unlikely(ret))
return ret;
if (unlikely(req->buf_index >= ctx->nr_user_bufs))
return -EFAULT;
index = array_index_nospec(req->buf_index, ctx->nr_user_bufs);
req->imu = ctx->user_bufs[index];
io_req_set_rsrc_node(req, ctx, 0);
return 0;
}
/*
* Multishot read is prepared just like a normal read/write request, only
* difference is that we set the MULTISHOT flag.

View File

@ -17,6 +17,7 @@ struct io_async_rw {
int io_prep_rw(struct io_kiocb *req, const struct io_uring_sqe *sqe);
int io_prep_rwv(struct io_kiocb *req, const struct io_uring_sqe *sqe);
int io_prep_rw_fixed(struct io_kiocb *req, const struct io_uring_sqe *sqe);
int io_read(struct io_kiocb *req, unsigned int issue_flags);
int io_readv_prep_async(struct io_kiocb *req);
int io_write(struct io_kiocb *req, unsigned int issue_flags);