Commit a04b0ac0 authored by Pavel Begunkov's avatar Pavel Begunkov Committed by Jens Axboe
Browse files

io_uring: encapsulate fixed files into struct 



Add struct io_fixed_file representing a single registered file, first to
hide ugly struct file **, which may be misleading, and secondly to
retype it to unsigned long as conversions to it and back to file * for
handling and masking FFS_* flags are getting nasty.

Signed-off-by: default avatarPavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/78669731a605a7614c577c3de552631cfaf0869a.1617287883.git.asml.silence@gmail.com


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 846a4ef2

fs/io_uring.c

+19 −13
Original line number Diff line number Diff line
@@ -207,6 +207,11 @@ struct io_overflow_cqe { 
	struct list_head list;

};



struct io_fixed_file {

	/* file * with additional FFS_* flags */

	unsigned long file_ptr;

};



struct io_rsrc_put {

	struct list_head list;

	union {
@@ -216,7 +221,7 @@ struct io_rsrc_put { 
};



struct fixed_rsrc_table {

	struct file		**files;

	struct io_fixed_file *files;

};



struct io_rsrc_node {
@@ -6275,7 +6280,7 @@ static void io_wq_submit_work(struct io_wq_work *work) 
#endif

#define FFS_MASK		~(FFS_ASYNC_READ|FFS_ASYNC_WRITE|FFS_ISREG)



static inline struct file **io_fixed_file_slot(struct io_rsrc_data *file_data,

static inline struct io_fixed_file *io_fixed_file_slot(struct io_rsrc_data *file_data,

						      unsigned i)

{

	struct fixed_rsrc_table *table;
@@ -6287,12 +6292,12 @@ static inline struct file **io_fixed_file_slot(struct io_rsrc_data *file_data, 
static inline struct file *io_file_from_index(struct io_ring_ctx *ctx,

					      int index)

{

	struct file **file_slot = io_fixed_file_slot(ctx->file_data, index);

	struct io_fixed_file *slot = io_fixed_file_slot(ctx->file_data, index);



	return (struct file *) ((unsigned long) *file_slot & FFS_MASK);

	return (struct file *) (slot->file_ptr & FFS_MASK);

}



static void io_fixed_file_set(struct file **file_slot, struct file *file)

static void io_fixed_file_set(struct io_fixed_file *file_slot, struct file *file)

{

	unsigned long file_ptr = (unsigned long) file;
@@ -6302,7 +6307,7 @@ static void io_fixed_file_set(struct file **file_slot, struct file *file) 
		file_ptr |= FFS_ASYNC_WRITE;

	if (S_ISREG(file_inode(file)->i_mode))

		file_ptr |= FFS_ISREG;

	*file_slot = (struct file *)file_ptr;

	file_slot->file_ptr = file_ptr;

}



static struct file *io_file_get(struct io_submit_state *state,
@@ -6317,7 +6322,7 @@ static struct file *io_file_get(struct io_submit_state *state, 
		if (unlikely((unsigned int)fd >= ctx->nr_user_files))

			return NULL;

		fd = array_index_nospec(fd, ctx->nr_user_files);

		file_ptr = (unsigned long) *io_fixed_file_slot(ctx->file_data, fd);

		file_ptr = io_fixed_file_slot(ctx->file_data, fd)->file_ptr;

		file = (struct file *) (file_ptr & FFS_MASK);

		file_ptr &= ~FFS_MASK;

		/* mask in overlapping REQ_F and FFS bits */
@@ -7756,7 +7761,8 @@ static int __io_sqe_files_update(struct io_ring_ctx *ctx, 
				 unsigned nr_args)

{

	struct io_rsrc_data *data = ctx->file_data;

	struct file *file, **file_slot;

	struct io_fixed_file *file_slot;

	struct file *file;

	__s32 __user *fds;

	int fd, i, err;

	__u32 done;
@@ -7783,12 +7789,12 @@ static int __io_sqe_files_update(struct io_ring_ctx *ctx, 
		i = array_index_nospec(up->offset + done, ctx->nr_user_files);

		file_slot = io_fixed_file_slot(ctx->file_data, i);



		if (*file_slot) {

			file = (struct file *) ((unsigned long) *file_slot & FFS_MASK);

		if (file_slot->file_ptr) {

			file = (struct file *)(file_slot->file_ptr & FFS_MASK);

			err = io_queue_rsrc_removal(data, ctx->rsrc_node, file);

			if (err)

				break;

			*file_slot = NULL;

			file_slot->file_ptr = 0;

			needs_switch = true;

		}

		if (fd != -1) {
@@ -7813,7 +7819,7 @@ static int __io_sqe_files_update(struct io_ring_ctx *ctx, 
			io_fixed_file_set(file_slot, file);

			err = io_sqe_file_register(ctx, file, i);

			if (err) {

				*file_slot = NULL;

				file_slot->file_ptr = 0;

				fput(file);

				break;

			}