io_uring: move read/write file prep state into actual opcode handler

In preparation for not necessarily having a file assigned at prep time,
defer any initialization associated with the file to when the opcode
handler is run.

Cc: stable@vger.kernel.org # v5.15+
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Jens Axboe 2022-03-29 10:48:05 -06:00
parent a3e4bc23d5
commit 584b0180f0

View file

@ -592,7 +592,8 @@ struct io_rw {
/* NOTE: kiocb has the file as the first member, so don't do it here */
struct kiocb kiocb;
u64 addr;
u64 len;
u32 len;
u32 flags;
};
struct io_connect {
@ -3178,42 +3179,11 @@ static inline bool io_file_supports_nowait(struct io_kiocb *req)
static int io_prep_rw(struct io_kiocb *req, const struct io_uring_sqe *sqe)
{
struct io_ring_ctx *ctx = req->ctx;
struct kiocb *kiocb = &req->rw.kiocb;
struct file *file = req->file;
unsigned ioprio;
int ret;
if (!io_req_ffs_set(req))
req->flags |= io_file_get_flags(file) << REQ_F_SUPPORT_NOWAIT_BIT;
kiocb->ki_pos = READ_ONCE(sqe->off);
kiocb->ki_flags = iocb_flags(file);
ret = kiocb_set_rw_flags(kiocb, READ_ONCE(sqe->rw_flags));
if (unlikely(ret))
return ret;
/*
* If the file is marked O_NONBLOCK, still allow retry for it if it
* supports async. Otherwise it's impossible to use O_NONBLOCK files
* reliably. If not, or it IOCB_NOWAIT is set, don't retry.
*/
if ((kiocb->ki_flags & IOCB_NOWAIT) ||
((file->f_flags & O_NONBLOCK) && !io_file_supports_nowait(req)))
req->flags |= REQ_F_NOWAIT;
if (ctx->flags & IORING_SETUP_IOPOLL) {
if (!(kiocb->ki_flags & IOCB_DIRECT) || !file->f_op->iopoll)
return -EOPNOTSUPP;
kiocb->ki_flags |= IOCB_HIPRI | IOCB_ALLOC_CACHE;
kiocb->ki_complete = io_complete_rw_iopoll;
req->iopoll_completed = 0;
} else {
if (kiocb->ki_flags & IOCB_HIPRI)
return -EINVAL;
kiocb->ki_complete = io_complete_rw;
}
ioprio = READ_ONCE(sqe->ioprio);
if (ioprio) {
@ -3229,6 +3199,7 @@ static int io_prep_rw(struct io_kiocb *req, const struct io_uring_sqe *sqe)
req->imu = NULL;
req->rw.addr = READ_ONCE(sqe->addr);
req->rw.len = READ_ONCE(sqe->len);
req->rw.flags = READ_ONCE(sqe->rw_flags);
req->buf_index = READ_ONCE(sqe->buf_index);
return 0;
}
@ -3732,13 +3703,6 @@ static inline int io_rw_prep_async(struct io_kiocb *req, int rw)
return 0;
}
static int io_read_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
{
if (unlikely(!(req->file->f_mode & FMODE_READ)))
return -EBADF;
return io_prep_rw(req, sqe);
}
/*
* This is our waitqueue callback handler, registered through __folio_lock_async()
* when we initially tried to do the IO with the iocb armed our waitqueue.
@ -3826,6 +3790,49 @@ static bool need_read_all(struct io_kiocb *req)
S_ISBLK(file_inode(req->file)->i_mode);
}
static int io_rw_init_file(struct io_kiocb *req, fmode_t mode)
{
struct kiocb *kiocb = &req->rw.kiocb;
struct io_ring_ctx *ctx = req->ctx;
struct file *file = req->file;
int ret;
if (unlikely(!file || !(file->f_mode & mode)))
return -EBADF;
if (!io_req_ffs_set(req))
req->flags |= io_file_get_flags(file) << REQ_F_SUPPORT_NOWAIT_BIT;
kiocb->ki_flags = iocb_flags(file);
ret = kiocb_set_rw_flags(kiocb, req->rw.flags);
if (unlikely(ret))
return ret;
/*
* If the file is marked O_NONBLOCK, still allow retry for it if it
* supports async. Otherwise it's impossible to use O_NONBLOCK files
* reliably. If not, or it IOCB_NOWAIT is set, don't retry.
*/
if ((kiocb->ki_flags & IOCB_NOWAIT) ||
((file->f_flags & O_NONBLOCK) && !io_file_supports_nowait(req)))
req->flags |= REQ_F_NOWAIT;
if (ctx->flags & IORING_SETUP_IOPOLL) {
if (!(kiocb->ki_flags & IOCB_DIRECT) || !file->f_op->iopoll)
return -EOPNOTSUPP;
kiocb->ki_flags |= IOCB_HIPRI | IOCB_ALLOC_CACHE;
kiocb->ki_complete = io_complete_rw_iopoll;
req->iopoll_completed = 0;
} else {
if (kiocb->ki_flags & IOCB_HIPRI)
return -EINVAL;
kiocb->ki_complete = io_complete_rw;
}
return 0;
}
static int io_read(struct io_kiocb *req, unsigned int issue_flags)
{
struct io_rw_state __s, *s = &__s;
@ -3861,6 +3868,9 @@ static int io_read(struct io_kiocb *req, unsigned int issue_flags)
iov_iter_restore(&s->iter, &s->iter_state);
iovec = NULL;
}
ret = io_rw_init_file(req, FMODE_READ);
if (unlikely(ret))
return ret;
req->result = iov_iter_count(&s->iter);
if (force_nonblock) {
@ -3964,13 +3974,6 @@ static int io_read(struct io_kiocb *req, unsigned int issue_flags)
return 0;
}
static int io_write_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
{
if (unlikely(!(req->file->f_mode & FMODE_WRITE)))
return -EBADF;
return io_prep_rw(req, sqe);
}
static int io_write(struct io_kiocb *req, unsigned int issue_flags)
{
struct io_rw_state __s, *s = &__s;
@ -3991,6 +3994,9 @@ static int io_write(struct io_kiocb *req, unsigned int issue_flags)
iov_iter_restore(&s->iter, &s->iter_state);
iovec = NULL;
}
ret = io_rw_init_file(req, FMODE_WRITE);
if (unlikely(ret))
return ret;
req->result = iov_iter_count(&s->iter);
if (force_nonblock) {
@ -6987,11 +6993,10 @@ static int io_req_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
case IORING_OP_READV:
case IORING_OP_READ_FIXED:
case IORING_OP_READ:
return io_read_prep(req, sqe);
case IORING_OP_WRITEV:
case IORING_OP_WRITE_FIXED:
case IORING_OP_WRITE:
return io_write_prep(req, sqe);
return io_prep_rw(req, sqe);
case IORING_OP_POLL_ADD:
return io_poll_add_prep(req, sqe);
case IORING_OP_POLL_REMOVE: