[PATCHSET 0/6] Misc cleanups

[PATCHSET 0/6] Misc cleanups

[Jens Axboe]

Hi,

Just a few minor consistency fixups that I found while starting the
io_uring.c move and split. Aiming to put these into 5.19 to avoid
any extra hassle on the 5.20 front.

-- 
Jens Axboe

[PATCH 1/6] io_uring: make timeout prep handlers consistent with other prep handlers

[Jens Axboe]

All other opcodes take a {req, sqe} set for prep handling, split out
a timeout prep handler so that timeout and linked timeouts can use
the same one.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
---
 fs/io_uring.c | 21 +++++++++++++++++----
 1 file changed, 17 insertions(+), 4 deletions(-)

diff --git a/fs/io_uring.c b/fs/io_uring.c
index 9f1c682d7caf..c3991034b26a 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -7698,8 +7698,9 @@ static int io_timeout_remove(struct io_kiocb *req, unsigned int issue_flags)
 	return 0;
 }
 
-static int io_timeout_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe,
-			   bool is_timeout_link)
+static int __io_timeout_prep(struct io_kiocb *req,
+			     const struct io_uring_sqe *sqe,
+			     bool is_timeout_link)
 {
 	struct io_timeout_data *data;
 	unsigned flags;
@@ -7754,6 +7755,18 @@ static int io_timeout_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe,
 	return 0;
 }
 
+static int io_timeout_prep(struct io_kiocb *req,
+			   const struct io_uring_sqe *sqe)
+{
+	return __io_timeout_prep(req, sqe, false);
+}
+
+static int io_link_timeout_prep(struct io_kiocb *req,
+				const struct io_uring_sqe *sqe)
+{
+	return __io_timeout_prep(req, sqe, true);
+}
+
 static int io_timeout(struct io_kiocb *req, unsigned int issue_flags)
 {
 	struct io_ring_ctx *ctx = req->ctx;
@@ -8039,13 +8052,13 @@ static int io_req_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
 	case IORING_OP_CONNECT:
 		return io_connect_prep(req, sqe);
 	case IORING_OP_TIMEOUT:
-		return io_timeout_prep(req, sqe, false);
+		return io_timeout_prep(req, sqe);
 	case IORING_OP_TIMEOUT_REMOVE:
 		return io_timeout_remove_prep(req, sqe);
 	case IORING_OP_ASYNC_CANCEL:
 		return io_async_cancel_prep(req, sqe);
 	case IORING_OP_LINK_TIMEOUT:
-		return io_timeout_prep(req, sqe, true);
+		return io_link_timeout_prep(req, sqe);
 	case IORING_OP_ACCEPT:
 		return io_accept_prep(req, sqe);
 	case IORING_OP_FALLOCATE:
-- 
2.35.1

Re: [PATCH 1/6] io_uring: make timeout prep handlers consistent with other prep handlers

[Kanchan Joshi]

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On Tue, May 24, 2022 at 03:37:22PM -0600, Jens Axboe wrote:
>All other opcodes take a {req, sqe} set for prep handling, split out
>a timeout prep handler so that timeout and linked timeouts can use
>the same one.

Reviewed-by: Kanchan Joshi <joshi.k@samsung.com>

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[PATCH 2/6] io_uring: make prep and issue side of req handlers named consistently

[Jens Axboe]

Almost all of them are, the odd ones out are the poll remove and the
files update request. Name them like the others, which is:

io_#cmdname_prep	for request preparation
io_#cmdname		for request issue

Signed-off-by: Jens Axboe <axboe@kernel.dk>
---
 fs/io_uring.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/fs/io_uring.c b/fs/io_uring.c
index c3991034b26a..01a96fcdb7c6 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -7390,7 +7390,7 @@ static __poll_t io_poll_parse_events(const struct io_uring_sqe *sqe,
 	return demangle_poll(events) | (events & (EPOLLEXCLUSIVE|EPOLLONESHOT));
 }
 
-static int io_poll_update_prep(struct io_kiocb *req,
+static int io_poll_remove_prep(struct io_kiocb *req,
 			       const struct io_uring_sqe *sqe)
 {
 	struct io_poll_update *upd = &req->poll_update;
@@ -7454,7 +7454,7 @@ static int io_poll_add(struct io_kiocb *req, unsigned int issue_flags)
 	return 0;
 }
 
-static int io_poll_update(struct io_kiocb *req, unsigned int issue_flags)
+static int io_poll_remove(struct io_kiocb *req, unsigned int issue_flags)
 {
 	struct io_cancel_data cd = { .data = req->poll_update.old_user_data, };
 	struct io_ring_ctx *ctx = req->ctx;
@@ -7983,7 +7983,7 @@ static int io_async_cancel(struct io_kiocb *req, unsigned int issue_flags)
 	return 0;
 }
 
-static int io_rsrc_update_prep(struct io_kiocb *req,
+static int io_files_update_prep(struct io_kiocb *req,
 				const struct io_uring_sqe *sqe)
 {
 	if (unlikely(req->flags & (REQ_F_FIXED_FILE | REQ_F_BUFFER_SELECT)))
@@ -8038,7 +8038,7 @@ static int io_req_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
 	case IORING_OP_POLL_ADD:
 		return io_poll_add_prep(req, sqe);
 	case IORING_OP_POLL_REMOVE:
-		return io_poll_update_prep(req, sqe);
+		return io_poll_remove_prep(req, sqe);
 	case IORING_OP_FSYNC:
 		return io_fsync_prep(req, sqe);
 	case IORING_OP_SYNC_FILE_RANGE:
@@ -8068,7 +8068,7 @@ static int io_req_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
 	case IORING_OP_CLOSE:
 		return io_close_prep(req, sqe);
 	case IORING_OP_FILES_UPDATE:
-		return io_rsrc_update_prep(req, sqe);
+		return io_files_update_prep(req, sqe);
 	case IORING_OP_STATX:
 		return io_statx_prep(req, sqe);
 	case IORING_OP_FADVISE:
@@ -8334,7 +8334,7 @@ static int io_issue_sqe(struct io_kiocb *req, unsigned int issue_flags)
 		ret = io_poll_add(req, issue_flags);
 		break;
 	case IORING_OP_POLL_REMOVE:
-		ret = io_poll_update(req, issue_flags);
+		ret = io_poll_remove(req, issue_flags);
 		break;
 	case IORING_OP_SYNC_FILE_RANGE:
 		ret = io_sync_file_range(req, issue_flags);
-- 
2.35.1

Re: [PATCH 2/6] io_uring: make prep and issue side of req handlers named consistently

[Kanchan Joshi]

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On Tue, May 24, 2022 at 03:37:23PM -0600, Jens Axboe wrote:
>Almost all of them are, the odd ones out are the poll remove and the
>files update request. Name them like the others, which is:
>
>io_#cmdname_prep	for request preparation
>io_#cmdname		for request issue

        case IORING_OP_READV:
        case IORING_OP_READ_FIXED:
        case IORING_OP_READ:
        case IORING_OP_WRITEV:
        case IORING_OP_WRITE_FIXED:
        case IORING_OP_WRITE:
                return io_prep_rw(req, sqe);

Should io_prep_rw be renamed to io_rw_prep as well?
Looks good.
Reviewed-by: Kanchan Joshi <joshi.k@samsung.com>


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[PATCH 3/6] io_uring: add io_op_defs 'def' pointer in req init and issue

[Jens Axboe]

Define and set it when appropriate, and use it consistently in the
function rather than using io_op_defs[opcode].

Signed-off-by: Jens Axboe <axboe@kernel.dk>
---
 fs/io_uring.c | 17 ++++++++++-------
 1 file changed, 10 insertions(+), 7 deletions(-)

diff --git a/fs/io_uring.c b/fs/io_uring.c
index 01a96fcdb7c6..d2c99176b11a 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -8301,6 +8301,7 @@ static bool io_assign_file(struct io_kiocb *req, unsigned int issue_flags)
 
 static int io_issue_sqe(struct io_kiocb *req, unsigned int issue_flags)
 {
+	const struct io_op_def *def = &io_op_defs[req->opcode];
 	const struct cred *creds = NULL;
 	int ret;
 
@@ -8310,7 +8311,7 @@ static int io_issue_sqe(struct io_kiocb *req, unsigned int issue_flags)
 	if (unlikely((req->flags & REQ_F_CREDS) && req->creds != current_cred()))
 		creds = override_creds(req->creds);
 
-	if (!io_op_defs[req->opcode].audit_skip)
+	if (!def->audit_skip)
 		audit_uring_entry(req->opcode);
 
 	switch (req->opcode) {
@@ -8449,7 +8450,7 @@ static int io_issue_sqe(struct io_kiocb *req, unsigned int issue_flags)
 		break;
 	}
 
-	if (!io_op_defs[req->opcode].audit_skip)
+	if (!def->audit_skip)
 		audit_uring_exit(!ret, ret);
 
 	if (creds)
@@ -8801,12 +8802,14 @@ static int io_init_req(struct io_ring_ctx *ctx, struct io_kiocb *req,
 		       const struct io_uring_sqe *sqe)
 	__must_hold(&ctx->uring_lock)
 {
+	const struct io_op_def *def;
 	unsigned int sqe_flags;
 	int personality;
 	u8 opcode;
 
 	/* req is partially pre-initialised, see io_preinit_req() */
 	req->opcode = opcode = READ_ONCE(sqe->opcode);
+	def = &io_op_defs[opcode];
 	/* same numerical values with corresponding REQ_F_*, safe to copy */
 	req->flags = sqe_flags = READ_ONCE(sqe->flags);
 	req->cqe.user_data = READ_ONCE(sqe->user_data);
@@ -8823,7 +8826,7 @@ static int io_init_req(struct io_ring_ctx *ctx, struct io_kiocb *req,
 		if (sqe_flags & ~SQE_VALID_FLAGS)
 			return -EINVAL;
 		if (sqe_flags & IOSQE_BUFFER_SELECT) {
-			if (!io_op_defs[opcode].buffer_select)
+			if (!def->buffer_select)
 				return -EOPNOTSUPP;
 			req->buf_index = READ_ONCE(sqe->buf_group);
 		}
@@ -8849,12 +8852,12 @@ static int io_init_req(struct io_ring_ctx *ctx, struct io_kiocb *req,
 		}
 	}
 
-	if (!io_op_defs[opcode].ioprio && sqe->ioprio)
+	if (!def->ioprio && sqe->ioprio)
 		return -EINVAL;
-	if (!io_op_defs[opcode].iopoll && (ctx->flags & IORING_SETUP_IOPOLL))
+	if (!def->iopoll && (ctx->flags & IORING_SETUP_IOPOLL))
 		return -EINVAL;
 
-	if (io_op_defs[opcode].needs_file) {
+	if (def->needs_file) {
 		struct io_submit_state *state = &ctx->submit_state;
 
 		req->cqe.fd = READ_ONCE(sqe->fd);
@@ -8863,7 +8866,7 @@ static int io_init_req(struct io_ring_ctx *ctx, struct io_kiocb *req,
 		 * Plug now if we have more than 2 IO left after this, and the
 		 * target is potentially a read/write to block based storage.
 		 */
-		if (state->need_plug && io_op_defs[opcode].plug) {
+		if (state->need_plug && def->plug) {
 			state->plug_started = true;
 			state->need_plug = false;
 			blk_start_plug_nr_ios(&state->plug, state->submit_nr);
-- 
2.35.1

Re: [PATCH 3/6] io_uring: add io_op_defs 'def' pointer in req init and issue

[Kanchan Joshi]

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On Tue, May 24, 2022 at 03:37:24PM -0600, Jens Axboe wrote:
>Define and set it when appropriate, and use it consistently in the
>function rather than using io_op_defs[opcode].

seems you skipped doing this inside io_alloc_async_data() because
access is not that repetitive.

Reviewed-by: Kanchan Joshi <joshi.k@samsung.com>

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Re: [PATCH 3/6] io_uring: add io_op_defs 'def' pointer in req init and issue

[Jens Axboe]

On 5/25/22 12:41 AM, Kanchan Joshi wrote:
> On Tue, May 24, 2022 at 03:37:24PM -0600, Jens Axboe wrote:
>> Define and set it when appropriate, and use it consistently in the
>> function rather than using io_op_defs[opcode].
> 
> seems you skipped doing this inside io_alloc_async_data() because
> access is not that repetitive.

Right, and because it won't get impacted by abstracting out opcode
handlers.

-- 
Jens Axboe

[PATCH 4/6] io_uring: unify calling convention for async prep handling

[Jens Axboe]

Make them consistent in preparation for defining a req async prep
handler. The readv/writev requests share a prep handler, move it one
level down so the initial one is consistent with the others.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
---
 fs/io_uring.c | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/fs/io_uring.c b/fs/io_uring.c
index d2c99176b11a..408265a03563 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -4176,6 +4176,16 @@ static inline int io_rw_prep_async(struct io_kiocb *req, int rw)
 	return 0;
 }
 
+static int io_readv_prep_async(struct io_kiocb *req)
+{
+	return io_rw_prep_async(req, READ);
+}
+
+static int io_writev_prep_async(struct io_kiocb *req)
+{
+	return io_rw_prep_async(req, READ);
+}
+
 /*
  * 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.
@@ -8136,9 +8146,9 @@ static int io_req_prep_async(struct io_kiocb *req)
 
 	switch (req->opcode) {
 	case IORING_OP_READV:
-		return io_rw_prep_async(req, READ);
+		return io_readv_prep_async(req);
 	case IORING_OP_WRITEV:
-		return io_rw_prep_async(req, WRITE);
+		return io_writev_prep_async(req);
 	case IORING_OP_SENDMSG:
 		return io_sendmsg_prep_async(req);
 	case IORING_OP_RECVMSG:
-- 
2.35.1

[PATCH 5/6] io_uring: drop confusion between cleanup flags

[Jens Axboe]

If the opcode only stores data that needs to be kfree'ed in
req->async_data, then it doesn't need special handling in
our cleanup handler.

This has the added bonus of removing knowledge of those kinds of
special async_data to the io_uring core.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
---
 fs/io_uring.c | 18 ------------------
 1 file changed, 18 deletions(-)

diff --git a/fs/io_uring.c b/fs/io_uring.c
index 408265a03563..8188c47956ad 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -8229,24 +8229,6 @@ static void io_clean_op(struct io_kiocb *req)
 
 	if (req->flags & REQ_F_NEED_CLEANUP) {
 		switch (req->opcode) {
-		case IORING_OP_READV:
-		case IORING_OP_READ_FIXED:
-		case IORING_OP_READ:
-		case IORING_OP_WRITEV:
-		case IORING_OP_WRITE_FIXED:
-		case IORING_OP_WRITE: {
-			struct io_async_rw *io = req->async_data;
-
-			kfree(io->free_iovec);
-			break;
-			}
-		case IORING_OP_RECVMSG:
-		case IORING_OP_SENDMSG: {
-			struct io_async_msghdr *io = req->async_data;
-
-			kfree(io->free_iov);
-			break;
-			}
 		case IORING_OP_OPENAT:
 		case IORING_OP_OPENAT2:
 			if (req->open.filename)
-- 
2.35.1

Re: [PATCH 5/6] io_uring: drop confusion between cleanup flags

[Kanchan Joshi]

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On Tue, May 24, 2022 at 03:37:26PM -0600, Jens Axboe wrote:
>If the opcode only stores data that needs to be kfree'ed in
>req->async_data, then it doesn't need special handling in
>our cleanup handler.
>
>This has the added bonus of removing knowledge of those kinds of
>special async_data to the io_uring core.
>
>Signed-off-by: Jens Axboe <axboe@kernel.dk>
>---
> fs/io_uring.c | 18 ------------------
> 1 file changed, 18 deletions(-)
>
>diff --git a/fs/io_uring.c b/fs/io_uring.c
>index 408265a03563..8188c47956ad 100644
>--- a/fs/io_uring.c
>+++ b/fs/io_uring.c
>@@ -8229,24 +8229,6 @@ static void io_clean_op(struct io_kiocb *req)
>
> 	if (req->flags & REQ_F_NEED_CLEANUP) {
> 		switch (req->opcode) {
>-		case IORING_OP_READV:
>-		case IORING_OP_READ_FIXED:
>-		case IORING_OP_READ:
>-		case IORING_OP_WRITEV:
>-		case IORING_OP_WRITE_FIXED:
>-		case IORING_OP_WRITE: {
>-			struct io_async_rw *io = req->async_data;
>-
>-			kfree(io->free_iovec);

Removing this kfree may cause a leak.
For READV/WRITEV atleast, io->free_iovec will hold the address of
allocated iovec array if input was larger than UIO_FASTIOV.

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Re: [PATCH 5/6] io_uring: drop confusion between cleanup flags

[Jens Axboe]

On 5/25/22 2:46 AM, Kanchan Joshi wrote:
> On Tue, May 24, 2022 at 03:37:26PM -0600, Jens Axboe wrote:
>> If the opcode only stores data that needs to be kfree'ed in
>> req->async_data, then it doesn't need special handling in
>> our cleanup handler.
>>
>> This has the added bonus of removing knowledge of those kinds of
>> special async_data to the io_uring core.
>>
>> Signed-off-by: Jens Axboe <axboe@kernel.dk>
>> ---
>> fs/io_uring.c | 18 ------------------
>> 1 file changed, 18 deletions(-)
>>
>> diff --git a/fs/io_uring.c b/fs/io_uring.c
>> index 408265a03563..8188c47956ad 100644
>> --- a/fs/io_uring.c
>> +++ b/fs/io_uring.c
>> @@ -8229,24 +8229,6 @@ static void io_clean_op(struct io_kiocb *req)
>>
>>     if (req->flags & REQ_F_NEED_CLEANUP) {
>>         switch (req->opcode) {
>> -        case IORING_OP_READV:
>> -        case IORING_OP_READ_FIXED:
>> -        case IORING_OP_READ:
>> -        case IORING_OP_WRITEV:
>> -        case IORING_OP_WRITE_FIXED:
>> -        case IORING_OP_WRITE: {
>> -            struct io_async_rw *io = req->async_data;
>> -
>> -            kfree(io->free_iovec);
> 
> Removing this kfree may cause a leak.
> For READV/WRITEV atleast, io->free_iovec will hold the address of
> allocated iovec array if input was larger than UIO_FASTIOV.

I think I was too tired when I did and saw it freeing ->async_data,
which is obviously not the case. I'll drop this one.


-- 
Jens Axboe

[PATCH 6/6] io_uring: move shutdown under the general net section

[Jens Axboe]

Gets rid of some ifdefs and enables use of the net defines for when
CONFIG_NET isn't set.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
---
 fs/io_uring.c | 66 +++++++++++++++++++++++----------------------------
 1 file changed, 30 insertions(+), 36 deletions(-)

diff --git a/fs/io_uring.c b/fs/io_uring.c
index 8188c47956ad..9624ab114a40 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -5113,42 +5113,6 @@ static int io_uring_cmd(struct io_kiocb *req, unsigned int issue_flags)
 	return 0;
 }
 
-static int io_shutdown_prep(struct io_kiocb *req,
-			    const struct io_uring_sqe *sqe)
-{
-#if defined(CONFIG_NET)
-	if (unlikely(sqe->off || sqe->addr || sqe->rw_flags ||
-		     sqe->buf_index || sqe->splice_fd_in))
-		return -EINVAL;
-
-	req->shutdown.how = READ_ONCE(sqe->len);
-	return 0;
-#else
-	return -EOPNOTSUPP;
-#endif
-}
-
-static int io_shutdown(struct io_kiocb *req, unsigned int issue_flags)
-{
-#if defined(CONFIG_NET)
-	struct socket *sock;
-	int ret;
-
-	if (issue_flags & IO_URING_F_NONBLOCK)
-		return -EAGAIN;
-
-	sock = sock_from_file(req->file);
-	if (unlikely(!sock))
-		return -ENOTSOCK;
-
-	ret = __sys_shutdown_sock(sock, req->shutdown.how);
-	io_req_complete(req, ret);
-	return 0;
-#else
-	return -EOPNOTSUPP;
-#endif
-}
-
 static int __io_splice_prep(struct io_kiocb *req,
 			    const struct io_uring_sqe *sqe)
 {
@@ -6073,6 +6037,34 @@ static int io_sync_file_range(struct io_kiocb *req, unsigned int issue_flags)
 }
 
 #if defined(CONFIG_NET)
+static int io_shutdown_prep(struct io_kiocb *req,
+			    const struct io_uring_sqe *sqe)
+{
+	if (unlikely(sqe->off || sqe->addr || sqe->rw_flags ||
+		     sqe->buf_index || sqe->splice_fd_in))
+		return -EINVAL;
+
+	req->shutdown.how = READ_ONCE(sqe->len);
+	return 0;
+}
+
+static int io_shutdown(struct io_kiocb *req, unsigned int issue_flags)
+{
+	struct socket *sock;
+	int ret;
+
+	if (issue_flags & IO_URING_F_NONBLOCK)
+		return -EAGAIN;
+
+	sock = sock_from_file(req->file);
+	if (unlikely(!sock))
+		return -ENOTSOCK;
+
+	ret = __sys_shutdown_sock(sock, req->shutdown.how);
+	io_req_complete(req, ret);
+	return 0;
+}
+
 static bool io_net_retry(struct socket *sock, int flags)
 {
 	if (!(flags & MSG_WAITALL))
@@ -6777,8 +6769,10 @@ IO_NETOP_PREP_ASYNC(recvmsg);
 IO_NETOP_PREP_ASYNC(connect);
 IO_NETOP_PREP(accept);
 IO_NETOP_PREP(socket);
+IO_NETOP_PREP(shutdown);
 IO_NETOP_FN(send);
 IO_NETOP_FN(recv);
+IO_NETOP_FN(shutdown);
 #endif /* CONFIG_NET */
 
 struct io_poll_table {
-- 
2.35.1