io_uring: move fdinfo helpers to its own file
This also means moving a bit more of the fixed file handling to the
filetable side, which makes sense separately too.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/io_uring/fdinfo.c b/io_uring/fdinfo.c
new file mode 100644
index 0000000..fcedde4
--- /dev/null
+++ b/io_uring/fdinfo.c
@@ -0,0 +1,191 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/file.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+#include <linux/io_uring.h>
+
+#include <uapi/linux/io_uring.h>
+
+#include "io_uring_types.h"
+#include "io_uring.h"
+#include "sqpoll.h"
+#include "fdinfo.h"
+
+#ifdef CONFIG_PROC_FS
+static __cold int io_uring_show_cred(struct seq_file *m, unsigned int id,
+ const struct cred *cred)
+{
+ struct user_namespace *uns = seq_user_ns(m);
+ struct group_info *gi;
+ kernel_cap_t cap;
+ unsigned __capi;
+ int g;
+
+ seq_printf(m, "%5d\n", id);
+ seq_put_decimal_ull(m, "\tUid:\t", from_kuid_munged(uns, cred->uid));
+ seq_put_decimal_ull(m, "\t\t", from_kuid_munged(uns, cred->euid));
+ seq_put_decimal_ull(m, "\t\t", from_kuid_munged(uns, cred->suid));
+ seq_put_decimal_ull(m, "\t\t", from_kuid_munged(uns, cred->fsuid));
+ seq_put_decimal_ull(m, "\n\tGid:\t", from_kgid_munged(uns, cred->gid));
+ seq_put_decimal_ull(m, "\t\t", from_kgid_munged(uns, cred->egid));
+ seq_put_decimal_ull(m, "\t\t", from_kgid_munged(uns, cred->sgid));
+ seq_put_decimal_ull(m, "\t\t", from_kgid_munged(uns, cred->fsgid));
+ seq_puts(m, "\n\tGroups:\t");
+ gi = cred->group_info;
+ for (g = 0; g < gi->ngroups; g++) {
+ seq_put_decimal_ull(m, g ? " " : "",
+ from_kgid_munged(uns, gi->gid[g]));
+ }
+ seq_puts(m, "\n\tCapEff:\t");
+ cap = cred->cap_effective;
+ CAP_FOR_EACH_U32(__capi)
+ seq_put_hex_ll(m, NULL, cap.cap[CAP_LAST_U32 - __capi], 8);
+ seq_putc(m, '\n');
+ return 0;
+}
+
+static __cold void __io_uring_show_fdinfo(struct io_ring_ctx *ctx,
+ struct seq_file *m)
+{
+ struct io_sq_data *sq = NULL;
+ struct io_overflow_cqe *ocqe;
+ struct io_rings *r = ctx->rings;
+ unsigned int sq_mask = ctx->sq_entries - 1, cq_mask = ctx->cq_entries - 1;
+ unsigned int sq_head = READ_ONCE(r->sq.head);
+ unsigned int sq_tail = READ_ONCE(r->sq.tail);
+ unsigned int cq_head = READ_ONCE(r->cq.head);
+ unsigned int cq_tail = READ_ONCE(r->cq.tail);
+ unsigned int cq_shift = 0;
+ unsigned int sq_entries, cq_entries;
+ bool has_lock;
+ bool is_cqe32 = (ctx->flags & IORING_SETUP_CQE32);
+ unsigned int i;
+
+ if (is_cqe32)
+ cq_shift = 1;
+
+ /*
+ * we may get imprecise sqe and cqe info if uring is actively running
+ * since we get cached_sq_head and cached_cq_tail without uring_lock
+ * and sq_tail and cq_head are changed by userspace. But it's ok since
+ * we usually use these info when it is stuck.
+ */
+ seq_printf(m, "SqMask:\t0x%x\n", sq_mask);
+ seq_printf(m, "SqHead:\t%u\n", sq_head);
+ seq_printf(m, "SqTail:\t%u\n", sq_tail);
+ seq_printf(m, "CachedSqHead:\t%u\n", ctx->cached_sq_head);
+ seq_printf(m, "CqMask:\t0x%x\n", cq_mask);
+ seq_printf(m, "CqHead:\t%u\n", cq_head);
+ seq_printf(m, "CqTail:\t%u\n", cq_tail);
+ seq_printf(m, "CachedCqTail:\t%u\n", ctx->cached_cq_tail);
+ seq_printf(m, "SQEs:\t%u\n", sq_tail - ctx->cached_sq_head);
+ sq_entries = min(sq_tail - sq_head, ctx->sq_entries);
+ for (i = 0; i < sq_entries; i++) {
+ unsigned int entry = i + sq_head;
+ unsigned int sq_idx = READ_ONCE(ctx->sq_array[entry & sq_mask]);
+ struct io_uring_sqe *sqe;
+
+ if (sq_idx > sq_mask)
+ continue;
+ sqe = &ctx->sq_sqes[sq_idx];
+ seq_printf(m, "%5u: opcode:%d, fd:%d, flags:%x, user_data:%llu\n",
+ sq_idx, sqe->opcode, sqe->fd, sqe->flags,
+ sqe->user_data);
+ }
+ seq_printf(m, "CQEs:\t%u\n", cq_tail - cq_head);
+ cq_entries = min(cq_tail - cq_head, ctx->cq_entries);
+ for (i = 0; i < cq_entries; i++) {
+ unsigned int entry = i + cq_head;
+ struct io_uring_cqe *cqe = &r->cqes[(entry & cq_mask) << cq_shift];
+
+ if (!is_cqe32) {
+ seq_printf(m, "%5u: user_data:%llu, res:%d, flag:%x\n",
+ entry & cq_mask, cqe->user_data, cqe->res,
+ cqe->flags);
+ } else {
+ seq_printf(m, "%5u: user_data:%llu, res:%d, flag:%x, "
+ "extra1:%llu, extra2:%llu\n",
+ entry & cq_mask, cqe->user_data, cqe->res,
+ cqe->flags, cqe->big_cqe[0], cqe->big_cqe[1]);
+ }
+ }
+
+ /*
+ * Avoid ABBA deadlock between the seq lock and the io_uring mutex,
+ * since fdinfo case grabs it in the opposite direction of normal use
+ * cases. If we fail to get the lock, we just don't iterate any
+ * structures that could be going away outside the io_uring mutex.
+ */
+ has_lock = mutex_trylock(&ctx->uring_lock);
+
+ if (has_lock && (ctx->flags & IORING_SETUP_SQPOLL)) {
+ sq = ctx->sq_data;
+ if (!sq->thread)
+ sq = NULL;
+ }
+
+ seq_printf(m, "SqThread:\t%d\n", sq ? task_pid_nr(sq->thread) : -1);
+ seq_printf(m, "SqThreadCpu:\t%d\n", sq ? task_cpu(sq->thread) : -1);
+ seq_printf(m, "UserFiles:\t%u\n", ctx->nr_user_files);
+ for (i = 0; has_lock && i < ctx->nr_user_files; i++) {
+ struct file *f = io_file_from_index(&ctx->file_table, i);
+
+ if (f)
+ seq_printf(m, "%5u: %s\n", i, file_dentry(f)->d_iname);
+ else
+ seq_printf(m, "%5u: <none>\n", i);
+ }
+ seq_printf(m, "UserBufs:\t%u\n", ctx->nr_user_bufs);
+ for (i = 0; has_lock && i < ctx->nr_user_bufs; i++) {
+ struct io_mapped_ubuf *buf = ctx->user_bufs[i];
+ unsigned int len = buf->ubuf_end - buf->ubuf;
+
+ seq_printf(m, "%5u: 0x%llx/%u\n", i, buf->ubuf, len);
+ }
+ if (has_lock && !xa_empty(&ctx->personalities)) {
+ unsigned long index;
+ const struct cred *cred;
+
+ seq_printf(m, "Personalities:\n");
+ xa_for_each(&ctx->personalities, index, cred)
+ io_uring_show_cred(m, index, cred);
+ }
+ if (has_lock)
+ mutex_unlock(&ctx->uring_lock);
+
+ seq_puts(m, "PollList:\n");
+ spin_lock(&ctx->completion_lock);
+ for (i = 0; i < (1U << ctx->cancel_hash_bits); i++) {
+ struct hlist_head *list = &ctx->cancel_hash[i];
+ struct io_kiocb *req;
+
+ hlist_for_each_entry(req, list, hash_node)
+ seq_printf(m, " op=%d, task_works=%d\n", req->opcode,
+ task_work_pending(req->task));
+ }
+
+ seq_puts(m, "CqOverflowList:\n");
+ list_for_each_entry(ocqe, &ctx->cq_overflow_list, list) {
+ struct io_uring_cqe *cqe = &ocqe->cqe;
+
+ seq_printf(m, " user_data=%llu, res=%d, flags=%x\n",
+ cqe->user_data, cqe->res, cqe->flags);
+
+ }
+
+ spin_unlock(&ctx->completion_lock);
+}
+
+__cold void io_uring_show_fdinfo(struct seq_file *m, struct file *f)
+{
+ struct io_ring_ctx *ctx = f->private_data;
+
+ if (percpu_ref_tryget(&ctx->refs)) {
+ __io_uring_show_fdinfo(ctx, m);
+ percpu_ref_put(&ctx->refs);
+ }
+}
+#endif
