1// SPDX-License-Identifier: GPL-2.0
2#include <linux/kernel.h>
3#include <linux/errno.h>
4#include <linux/fs.h>
5#include <linux/file.h>
6#include <linux/proc_fs.h>
7#include <linux/seq_file.h>
8#include <linux/io_uring.h>
9
10#include <uapi/linux/io_uring.h>
11
12#include "io_uring.h"
13#include "sqpoll.h"
14#include "fdinfo.h"
15#include "cancel.h"
16#include "rsrc.h"
17
18#ifdef CONFIG_PROC_FS
19static __cold int io_uring_show_cred(struct seq_file *m, unsigned int id,
20		const struct cred *cred)
21{
22	struct user_namespace *uns = seq_user_ns(m);
23	struct group_info *gi;
24	kernel_cap_t cap;
25	int g;
26
27	seq_printf(m, "%5d\n", id);
28	seq_put_decimal_ull(m, "\tUid:\t", from_kuid_munged(uns, cred->uid));
29	seq_put_decimal_ull(m, "\t\t", from_kuid_munged(uns, cred->euid));
30	seq_put_decimal_ull(m, "\t\t", from_kuid_munged(uns, cred->suid));
31	seq_put_decimal_ull(m, "\t\t", from_kuid_munged(uns, cred->fsuid));
32	seq_put_decimal_ull(m, "\n\tGid:\t", from_kgid_munged(uns, cred->gid));
33	seq_put_decimal_ull(m, "\t\t", from_kgid_munged(uns, cred->egid));
34	seq_put_decimal_ull(m, "\t\t", from_kgid_munged(uns, cred->sgid));
35	seq_put_decimal_ull(m, "\t\t", from_kgid_munged(uns, cred->fsgid));
36	seq_puts(m, "\n\tGroups:\t");
37	gi = cred->group_info;
38	for (g = 0; g < gi->ngroups; g++) {
39		seq_put_decimal_ull(m, g ? " " : "",
40					from_kgid_munged(uns, gi->gid[g]));
41	}
42	seq_puts(m, "\n\tCapEff:\t");
43	cap = cred->cap_effective;
44	seq_put_hex_ll(m, NULL, cap.val, 16);
45	seq_putc(m, '\n');
46	return 0;
47}
48
49/*
50 * Caller holds a reference to the file already, we don't need to do
51 * anything else to get an extra reference.
52 */
53__cold void io_uring_show_fdinfo(struct seq_file *m, struct file *f)
54{
55	struct io_ring_ctx *ctx = f->private_data;
56	struct io_overflow_cqe *ocqe;
57	struct io_rings *r = ctx->rings;
58	struct rusage sq_usage;
59	unsigned int sq_mask = ctx->sq_entries - 1, cq_mask = ctx->cq_entries - 1;
60	unsigned int sq_head = READ_ONCE(r->sq.head);
61	unsigned int sq_tail = READ_ONCE(r->sq.tail);
62	unsigned int cq_head = READ_ONCE(r->cq.head);
63	unsigned int cq_tail = READ_ONCE(r->cq.tail);
64	unsigned int cq_shift = 0;
65	unsigned int sq_shift = 0;
66	unsigned int sq_entries, cq_entries;
67	int sq_pid = -1, sq_cpu = -1;
68	u64 sq_total_time = 0, sq_work_time = 0;
69	bool has_lock;
70	unsigned int i;
71
72	if (ctx->flags & IORING_SETUP_CQE32)
73		cq_shift = 1;
74	if (ctx->flags & IORING_SETUP_SQE128)
75		sq_shift = 1;
76
77	/*
78	 * we may get imprecise sqe and cqe info if uring is actively running
79	 * since we get cached_sq_head and cached_cq_tail without uring_lock
80	 * and sq_tail and cq_head are changed by userspace. But it's ok since
81	 * we usually use these info when it is stuck.
82	 */
83	seq_printf(m, "SqMask:\t0x%x\n", sq_mask);
84	seq_printf(m, "SqHead:\t%u\n", sq_head);
85	seq_printf(m, "SqTail:\t%u\n", sq_tail);
86	seq_printf(m, "CachedSqHead:\t%u\n", ctx->cached_sq_head);
87	seq_printf(m, "CqMask:\t0x%x\n", cq_mask);
88	seq_printf(m, "CqHead:\t%u\n", cq_head);
89	seq_printf(m, "CqTail:\t%u\n", cq_tail);
90	seq_printf(m, "CachedCqTail:\t%u\n", ctx->cached_cq_tail);
91	seq_printf(m, "SQEs:\t%u\n", sq_tail - sq_head);
92	sq_entries = min(sq_tail - sq_head, ctx->sq_entries);
93	for (i = 0; i < sq_entries; i++) {
94		unsigned int entry = i + sq_head;
95		struct io_uring_sqe *sqe;
96		unsigned int sq_idx;
97
98		if (ctx->flags & IORING_SETUP_NO_SQARRAY)
99			break;
100		sq_idx = READ_ONCE(ctx->sq_array[entry & sq_mask]);
101		if (sq_idx > sq_mask)
102			continue;
103		sqe = &ctx->sq_sqes[sq_idx << sq_shift];
104		seq_printf(m, "%5u: opcode:%s, fd:%d, flags:%x, off:%llu, "
105			      "addr:0x%llx, rw_flags:0x%x, buf_index:%d "
106			      "user_data:%llu",
107			   sq_idx, io_uring_get_opcode(sqe->opcode), sqe->fd,
108			   sqe->flags, (unsigned long long) sqe->off,
109			   (unsigned long long) sqe->addr, sqe->rw_flags,
110			   sqe->buf_index, sqe->user_data);
111		if (sq_shift) {
112			u64 *sqeb = (void *) (sqe + 1);
113			int size = sizeof(struct io_uring_sqe) / sizeof(u64);
114			int j;
115
116			for (j = 0; j < size; j++) {
117				seq_printf(m, ", e%d:0x%llx", j,
118						(unsigned long long) *sqeb);
119				sqeb++;
120			}
121		}
122		seq_printf(m, "\n");
123	}
124	seq_printf(m, "CQEs:\t%u\n", cq_tail - cq_head);
125	cq_entries = min(cq_tail - cq_head, ctx->cq_entries);
126	for (i = 0; i < cq_entries; i++) {
127		unsigned int entry = i + cq_head;
128		struct io_uring_cqe *cqe = &r->cqes[(entry & cq_mask) << cq_shift];
129
130		seq_printf(m, "%5u: user_data:%llu, res:%d, flag:%x",
131			   entry & cq_mask, cqe->user_data, cqe->res,
132			   cqe->flags);
133		if (cq_shift)
134			seq_printf(m, ", extra1:%llu, extra2:%llu\n",
135					cqe->big_cqe[0], cqe->big_cqe[1]);
136		seq_printf(m, "\n");
137	}
138
139	/*
140	 * Avoid ABBA deadlock between the seq lock and the io_uring mutex,
141	 * since fdinfo case grabs it in the opposite direction of normal use
142	 * cases. If we fail to get the lock, we just don't iterate any
143	 * structures that could be going away outside the io_uring mutex.
144	 */
145	has_lock = mutex_trylock(&ctx->uring_lock);
146
147	if (has_lock && (ctx->flags & IORING_SETUP_SQPOLL)) {
148		struct io_sq_data *sq = ctx->sq_data;
149
150		/*
151		 * sq->thread might be NULL if we raced with the sqpoll
152		 * thread termination.
153		 */
154		if (sq->thread) {
155			sq_pid = sq->task_pid;
156			sq_cpu = sq->sq_cpu;
157			getrusage(sq->thread, RUSAGE_SELF, &sq_usage);
158			sq_total_time = (sq_usage.ru_stime.tv_sec * 1000000
159					 + sq_usage.ru_stime.tv_usec);
160			sq_work_time = sq->work_time;
161		}
162	}
163
164	seq_printf(m, "SqThread:\t%d\n", sq_pid);
165	seq_printf(m, "SqThreadCpu:\t%d\n", sq_cpu);
166	seq_printf(m, "SqTotalTime:\t%llu\n", sq_total_time);
167	seq_printf(m, "SqWorkTime:\t%llu\n", sq_work_time);
168	seq_printf(m, "UserFiles:\t%u\n", ctx->nr_user_files);
169	for (i = 0; has_lock && i < ctx->nr_user_files; i++) {
170		struct file *f = io_file_from_index(&ctx->file_table, i);
171
172		if (f)
173			seq_printf(m, "%5u: %s\n", i, file_dentry(f)->d_iname);
174		else
175			seq_printf(m, "%5u: <none>\n", i);
176	}
177	seq_printf(m, "UserBufs:\t%u\n", ctx->nr_user_bufs);
178	for (i = 0; has_lock && i < ctx->nr_user_bufs; i++) {
179		struct io_mapped_ubuf *buf = ctx->user_bufs[i];
180		unsigned int len = buf->ubuf_end - buf->ubuf;
181
182		seq_printf(m, "%5u: 0x%llx/%u\n", i, buf->ubuf, len);
183	}
184	if (has_lock && !xa_empty(&ctx->personalities)) {
185		unsigned long index;
186		const struct cred *cred;
187
188		seq_printf(m, "Personalities:\n");
189		xa_for_each(&ctx->personalities, index, cred)
190			io_uring_show_cred(m, index, cred);
191	}
192
193	seq_puts(m, "PollList:\n");
194	for (i = 0; i < (1U << ctx->cancel_table.hash_bits); i++) {
195		struct io_hash_bucket *hb = &ctx->cancel_table.hbs[i];
196		struct io_hash_bucket *hbl = &ctx->cancel_table_locked.hbs[i];
197		struct io_kiocb *req;
198
199		spin_lock(&hb->lock);
200		hlist_for_each_entry(req, &hb->list, hash_node)
201			seq_printf(m, "  op=%d, task_works=%d\n", req->opcode,
202					task_work_pending(req->task));
203		spin_unlock(&hb->lock);
204
205		if (!has_lock)
206			continue;
207		hlist_for_each_entry(req, &hbl->list, hash_node)
208			seq_printf(m, "  op=%d, task_works=%d\n", req->opcode,
209					task_work_pending(req->task));
210	}
211
212	if (has_lock)
213		mutex_unlock(&ctx->uring_lock);
214
215	seq_puts(m, "CqOverflowList:\n");
216	spin_lock(&ctx->completion_lock);
217	list_for_each_entry(ocqe, &ctx->cq_overflow_list, list) {
218		struct io_uring_cqe *cqe = &ocqe->cqe;
219
220		seq_printf(m, "  user_data=%llu, res=%d, flags=%x\n",
221			   cqe->user_data, cqe->res, cqe->flags);
222
223	}
224
225	spin_unlock(&ctx->completion_lock);
226}
227#endif
228