io_uring: allow sparse fixed file sets

This is in preparation for allowing updates to fixed file sets without
requiring a full unregister+register.

Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Jens Axboe 2019-10-03 08:11:03 -06:00
parent ba816ad61f
commit 08a451739a
1 changed files with 34 additions and 15 deletions

View File

@ -2379,6 +2379,8 @@ static int io_req_set_file(struct io_ring_ctx *ctx, const struct sqe_submit *s,
if (unlikely(!ctx->user_files ||
(unsigned) fd >= ctx->nr_user_files))
return -EBADF;
if (!ctx->user_files[fd])
return -EBADF;
req->file = ctx->user_files[fd];
req->flags |= REQ_F_FIXED_FILE;
} else {
@ -2999,7 +3001,8 @@ static void __io_sqe_files_unregister(struct io_ring_ctx *ctx)
int i;
for (i = 0; i < ctx->nr_user_files; i++)
fput(ctx->user_files[i]);
if (ctx->user_files[i])
fput(ctx->user_files[i]);
#endif
}
@ -3067,7 +3070,7 @@ static int __io_sqe_files_scm(struct io_ring_ctx *ctx, int nr, int offset)
struct sock *sk = ctx->ring_sock->sk;
struct scm_fp_list *fpl;
struct sk_buff *skb;
int i;
int i, nr_files;
if (!capable(CAP_SYS_RESOURCE) && !capable(CAP_SYS_ADMIN)) {
unsigned long inflight = ctx->user->unix_inflight + nr;
@ -3087,21 +3090,31 @@ static int __io_sqe_files_scm(struct io_ring_ctx *ctx, int nr, int offset)
}
skb->sk = sk;
skb->destructor = io_destruct_skb;
nr_files = 0;
fpl->user = get_uid(ctx->user);
for (i = 0; i < nr; i++) {
fpl->fp[i] = get_file(ctx->user_files[i + offset]);
unix_inflight(fpl->user, fpl->fp[i]);
if (!ctx->user_files[i + offset])
continue;
fpl->fp[nr_files] = get_file(ctx->user_files[i + offset]);
unix_inflight(fpl->user, fpl->fp[nr_files]);
nr_files++;
}
fpl->max = fpl->count = nr;
UNIXCB(skb).fp = fpl;
refcount_add(skb->truesize, &sk->sk_wmem_alloc);
skb_queue_head(&sk->sk_receive_queue, skb);
if (nr_files) {
fpl->max = SCM_MAX_FD;
fpl->count = nr_files;
UNIXCB(skb).fp = fpl;
skb->destructor = io_destruct_skb;
refcount_add(skb->truesize, &sk->sk_wmem_alloc);
skb_queue_head(&sk->sk_receive_queue, skb);
for (i = 0; i < nr; i++)
fput(fpl->fp[i]);
for (i = 0; i < nr_files; i++)
fput(fpl->fp[i]);
} else {
kfree_skb(skb);
kfree(fpl);
}
return 0;
}
@ -3132,7 +3145,8 @@ static int io_sqe_files_scm(struct io_ring_ctx *ctx)
return 0;
while (total < ctx->nr_user_files) {
fput(ctx->user_files[total]);
if (ctx->user_files[total])
fput(ctx->user_files[total]);
total++;
}
@ -3163,10 +3177,15 @@ static int io_sqe_files_register(struct io_ring_ctx *ctx, void __user *arg,
if (!ctx->user_files)
return -ENOMEM;
for (i = 0; i < nr_args; i++) {
for (i = 0; i < nr_args; i++, ctx->nr_user_files++) {
ret = -EFAULT;
if (copy_from_user(&fd, &fds[i], sizeof(fd)))
break;
/* allow sparse sets */
if (fd == -1) {
ret = 0;
continue;
}
ctx->user_files[i] = fget(fd);
@ -3184,13 +3203,13 @@ static int io_sqe_files_register(struct io_ring_ctx *ctx, void __user *arg,
fput(ctx->user_files[i]);
break;
}
ctx->nr_user_files++;
ret = 0;
}
if (ret) {
for (i = 0; i < ctx->nr_user_files; i++)
fput(ctx->user_files[i]);
if (ctx->user_files[i])
fput(ctx->user_files[i]);
kfree(ctx->user_files);
ctx->user_files = NULL;