Commit 0d98c509 authored by Ming Lei's avatar Ming Lei Committed by Jens Axboe
Browse files

io_uring/rsrc: pass 'struct io_ring_ctx' reference to rsrc helpers 



`io_rsrc_node` instance won't be shared among different io_uring ctxs,
and its allocation 'ctx' is always same with the user's 'ctx', so it is
safe to pass user 'ctx' reference to rsrc helpers. Even in io_clone_buffers(),
`io_rsrc_node` instance is allocated actually for destination io_uring_ctx.

Then io_rsrc_node_ctx() can be removed, and the 8 bytes `ctx` pointer will be
removed from `io_rsrc_node` in the following patch.

Signed-off-by: default avatarMing Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20241107110149.890530-2-ming.lei@redhat.com


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent af0a2ffe

io_uring/filetable.c

+7 −6
Original line number Diff line number Diff line
@@ -36,20 +36,21 @@ static int io_file_bitmap_get(struct io_ring_ctx *ctx) 
	return -ENFILE;

}



bool io_alloc_file_tables(struct io_file_table *table, unsigned nr_files)

bool io_alloc_file_tables(struct io_ring_ctx *ctx, struct io_file_table *table,

			  unsigned nr_files)

{

	if (io_rsrc_data_alloc(&table->data, nr_files))

		return false;

	table->bitmap = bitmap_zalloc(nr_files, GFP_KERNEL_ACCOUNT);

	if (table->bitmap)

		return true;

	io_rsrc_data_free(&table->data);

	io_rsrc_data_free(ctx, &table->data);

	return false;

}



void io_free_file_tables(struct io_file_table *table)

void io_free_file_tables(struct io_ring_ctx *ctx, struct io_file_table *table)

{

	io_rsrc_data_free(&table->data);

	io_rsrc_data_free(ctx, &table->data);

	bitmap_free(table->bitmap);

	table->bitmap = NULL;

}
@@ -71,7 +72,7 @@ static int io_install_fixed_file(struct io_ring_ctx *ctx, struct file *file, 
	if (!node)

		return -ENOMEM;



	if (!io_reset_rsrc_node(&ctx->file_table.data, slot_index))

	if (!io_reset_rsrc_node(ctx, &ctx->file_table.data, slot_index))

		io_file_bitmap_set(&ctx->file_table, slot_index);



	ctx->file_table.data.nodes[slot_index] = node;
@@ -130,7 +131,7 @@ int io_fixed_fd_remove(struct io_ring_ctx *ctx, unsigned int offset) 
	node = io_rsrc_node_lookup(&ctx->file_table.data, offset);

	if (!node)

		return -EBADF;

	io_reset_rsrc_node(&ctx->file_table.data, offset);

	io_reset_rsrc_node(ctx, &ctx->file_table.data, offset);

	io_file_bitmap_clear(&ctx->file_table, offset);

	return 0;

}

io_uring/filetable.h

+2 −2
Original line number Diff line number Diff line
@@ -6,8 +6,8 @@ 
#include <linux/io_uring_types.h>

#include "rsrc.h"



bool io_alloc_file_tables(struct io_file_table *table, unsigned nr_files);

void io_free_file_tables(struct io_file_table *table);

bool io_alloc_file_tables(struct io_ring_ctx *ctx, struct io_file_table *table, unsigned nr_files);

void io_free_file_tables(struct io_ring_ctx *ctx, struct io_file_table *table);



int io_fixed_fd_install(struct io_kiocb *req, unsigned int issue_flags,

			struct file *file, unsigned int file_slot);

io_uring/rsrc.c

+11 −13
Original line number Diff line number Diff line
@@ -130,13 +130,13 @@ struct io_rsrc_node *io_rsrc_node_alloc(struct io_ring_ctx *ctx, int type) 
	return node;

}



__cold void io_rsrc_data_free(struct io_rsrc_data *data)

__cold void io_rsrc_data_free(struct io_ring_ctx *ctx, struct io_rsrc_data *data)

{

	if (!data->nr)

		return;

	while (data->nr--) {

		if (data->nodes[data->nr])

			io_put_rsrc_node(data->nodes[data->nr]);

			io_put_rsrc_node(ctx, data->nodes[data->nr]);

	}

	kvfree(data->nodes);

	data->nodes = NULL;
@@ -184,7 +184,7 @@ static int __io_sqe_files_update(struct io_ring_ctx *ctx, 
			continue;



		i = up->offset + done;

		if (io_reset_rsrc_node(&ctx->file_table.data, i))

		if (io_reset_rsrc_node(ctx, &ctx->file_table.data, i))

			io_file_bitmap_clear(&ctx->file_table, i);



		if (fd != -1) {
@@ -266,7 +266,7 @@ static int __io_sqe_buffers_update(struct io_ring_ctx *ctx, 
			node->tag = tag;

		}

		i = array_index_nospec(up->offset + done, ctx->buf_table.nr);

		io_reset_rsrc_node(&ctx->buf_table, i);

		io_reset_rsrc_node(ctx, &ctx->buf_table, i);

		ctx->buf_table.nodes[i] = node;

		if (ctx->compat)

			user_data += sizeof(struct compat_iovec);
@@ -442,10 +442,8 @@ int io_files_update(struct io_kiocb *req, unsigned int issue_flags) 
	return IOU_OK;

}



void io_free_rsrc_node(struct io_rsrc_node *node)

void io_free_rsrc_node(struct io_ring_ctx *ctx, struct io_rsrc_node *node)

{

	struct io_ring_ctx *ctx = io_rsrc_node_ctx(node);



	lockdep_assert_held(&ctx->uring_lock);



	if (node->tag)
@@ -473,7 +471,7 @@ int io_sqe_files_unregister(struct io_ring_ctx *ctx) 
	if (!ctx->file_table.data.nr)

		return -ENXIO;



	io_free_file_tables(&ctx->file_table);

	io_free_file_tables(ctx, &ctx->file_table);

	io_file_table_set_alloc_range(ctx, 0, 0);

	return 0;

}
@@ -494,7 +492,7 @@ int io_sqe_files_register(struct io_ring_ctx *ctx, void __user *arg, 
		return -EMFILE;

	if (nr_args > rlimit(RLIMIT_NOFILE))

		return -EMFILE;

	if (!io_alloc_file_tables(&ctx->file_table, nr_args))

	if (!io_alloc_file_tables(ctx, &ctx->file_table, nr_args))

		return -ENOMEM;



	for (i = 0; i < nr_args; i++) {
@@ -551,7 +549,7 @@ int io_sqe_buffers_unregister(struct io_ring_ctx *ctx) 
{

	if (!ctx->buf_table.nr)

		return -ENXIO;

	io_rsrc_data_free(&ctx->buf_table);

	io_rsrc_data_free(ctx, &ctx->buf_table);

	return 0;

}
@@ -788,7 +786,7 @@ static struct io_rsrc_node *io_sqe_buffer_register(struct io_ring_ctx *ctx, 
	if (ret) {

		kvfree(imu);

		if (node)

			io_put_rsrc_node(node);

			io_put_rsrc_node(ctx, node);

		node = ERR_PTR(ret);

	}

	kvfree(pages);
@@ -1018,7 +1016,7 @@ static int io_clone_buffers(struct io_ring_ctx *ctx, struct io_ring_ctx *src_ctx 
	 * old and new nodes at this point.

	 */

	if (arg->flags & IORING_REGISTER_DST_REPLACE)

		io_rsrc_data_free(&ctx->buf_table);

		io_rsrc_data_free(ctx, &ctx->buf_table);



	/*

	 * ctx->buf_table should be empty now - either the contents are being
@@ -1042,7 +1040,7 @@ static int io_clone_buffers(struct io_ring_ctx *ctx, struct io_ring_ctx *src_ctx 
		kfree(data.nodes[i]);

	}

out_unlock:

	io_rsrc_data_free(&data);

	io_rsrc_data_free(ctx, &data);

	mutex_unlock(&src_ctx->uring_lock);

	mutex_lock(&ctx->uring_lock);

	return ret;

io_uring/rsrc.h

+9 −13
Original line number Diff line number Diff line
@@ -45,8 +45,8 @@ struct io_imu_folio_data { 
};



struct io_rsrc_node *io_rsrc_node_alloc(struct io_ring_ctx *ctx, int type);

void io_free_rsrc_node(struct io_rsrc_node *node);

void io_rsrc_data_free(struct io_rsrc_data *data);

void io_free_rsrc_node(struct io_ring_ctx *ctx, struct io_rsrc_node *node);

void io_rsrc_data_free(struct io_ring_ctx *ctx, struct io_rsrc_data *data);

int io_rsrc_data_alloc(struct io_rsrc_data *data, unsigned nr);



int io_import_fixed(int ddir, struct iov_iter *iter,
@@ -76,19 +76,20 @@ static inline struct io_rsrc_node *io_rsrc_node_lookup(struct io_rsrc_data *data 
	return NULL;

}



static inline void io_put_rsrc_node(struct io_rsrc_node *node)

static inline void io_put_rsrc_node(struct io_ring_ctx *ctx, struct io_rsrc_node *node)

{

	if (node && !--node->refs)

		io_free_rsrc_node(node);

		io_free_rsrc_node(ctx, node);

}



static inline bool io_reset_rsrc_node(struct io_rsrc_data *data, int index)

static inline bool io_reset_rsrc_node(struct io_ring_ctx *ctx,

				      struct io_rsrc_data *data, int index)

{

	struct io_rsrc_node *node = data->nodes[index];



	if (!node)

		return false;

	io_put_rsrc_node(node);

	io_put_rsrc_node(ctx, node);

	data->nodes[index] = NULL;

	return true;

}
@@ -96,20 +97,15 @@ static inline bool io_reset_rsrc_node(struct io_rsrc_data *data, int index) 
static inline void io_req_put_rsrc_nodes(struct io_kiocb *req)

{

	if (req->file_node) {

		io_put_rsrc_node(req->file_node);

		io_put_rsrc_node(req->ctx, req->file_node);

		req->file_node = NULL;

	}

	if (req->flags & REQ_F_BUF_NODE) {

		io_put_rsrc_node(req->buf_node);

		io_put_rsrc_node(req->ctx, req->buf_node);

		req->buf_node = NULL;

	}

}



static inline struct io_ring_ctx *io_rsrc_node_ctx(struct io_rsrc_node *node)

{

	return (struct io_ring_ctx *) (node->ctx_ptr & ~IORING_RSRC_TYPE_MASK);

}



static inline int io_rsrc_node_type(struct io_rsrc_node *node)

{

	return node->ctx_ptr & IORING_RSRC_TYPE_MASK;

io_uring/splice.c

+1 −1
Original line number Diff line number Diff line
@@ -51,7 +51,7 @@ void io_splice_cleanup(struct io_kiocb *req) 
{

	struct io_splice *sp = io_kiocb_to_cmd(req, struct io_splice);



	io_put_rsrc_node(sp->rsrc_node);

	io_put_rsrc_node(req->ctx, sp->rsrc_node);

}



static struct file *io_splice_get_file(struct io_kiocb *req,