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

source code of linux/io_uring/fdinfo.c