net/sunrpc/debugfs.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /**
   3  * debugfs interface for sunrpc
   4  *
   5  * (c) 2014 Jeff Layton <jlayton@primarydata.com>
   6  */
   7
   8 #include <linux/debugfs.h>
   9 #include <linux/sunrpc/sched.h>
  10 #include <linux/sunrpc/clnt.h>
  11 #include "netns.h"
  12
  13 static struct dentry *topdir;
  14 static struct dentry *rpc_clnt_dir;
  15 static struct dentry *rpc_xprt_dir;
  16
  17 unsigned int rpc_inject_disconnect;
  18
  19 static int
  20 tasks_show(struct seq_file *f, void *v)
  21 {
  22         u32 xid = 0;
  23         struct rpc_task *task = v;
  24         struct rpc_clnt *clnt = task->tk_client;
  25         const char *rpc_waitq = "none";
  26
  27         if (RPC_IS_QUEUED(task))
  28                 rpc_waitq = rpc_qname(task->tk_waitqueue);
  29
  30         if (task->tk_rqstp)
  31                 xid = be32_to_cpu(task->tk_rqstp->rq_xid);
  32
  33         seq_printf(f, "%5u %04x %6d 0x%x 0x%x %8ld %ps %sv%u %s a:%ps q:%s\n",
  34                 task->tk_pid, task->tk_flags, task->tk_status,
  35                 clnt->cl_clid, xid, rpc_task_timeout(task), task->tk_ops,
  36                 clnt->cl_program->name, clnt->cl_vers, rpc_proc_name(task),
  37                 task->tk_action, rpc_waitq);
  38         return 0;
  39 }
  40
  41 static void *
  42 tasks_start(struct seq_file *f, loff_t *ppos)
  43         __acquires(&clnt->cl_lock)
  44 {
  45         struct rpc_clnt *clnt = f->private;
  46         loff_t pos = *ppos;
  47         struct rpc_task *task;
  48
  49         spin_lock(&clnt->cl_lock);
  50         list_for_each_entry(task, &clnt->cl_tasks, tk_task)
  51                 if (pos-- == 0)
  52                         return task;
  53         return NULL;
  54 }
  55
  56 static void *
  57 tasks_next(struct seq_file *f, void *v, loff_t *pos)
  58 {
  59         struct rpc_clnt *clnt = f->private;
  60         struct rpc_task *task = v;
  61         struct list_head *next = task->tk_task.next;
  62
  63         ++*pos;
  64
  65         /* If there's another task on list, return it */
  66         if (next == &clnt->cl_tasks)
  67                 return NULL;
  68         return list_entry(next, struct rpc_task, tk_task);
  69 }
  70
  71 static void
  72 tasks_stop(struct seq_file *f, void *v)
  73         __releases(&clnt->cl_lock)
  74 {
  75         struct rpc_clnt *clnt = f->private;
  76         spin_unlock(&clnt->cl_lock);
  77 }
  78
  79 static const struct seq_operations tasks_seq_operations = {
  80         .start  = tasks_start,
  81         .next   = tasks_next,
  82         .stop   = tasks_stop,
  83         .show   = tasks_show,
  84 };
  85
  86 static int tasks_open(struct inode *inode, struct file *filp)
  87 {
  88         int ret = seq_open(filp, &tasks_seq_operations);
  89         if (!ret) {
  90                 struct seq_file *seq = filp->private_data;
  91                 struct rpc_clnt *clnt = seq->private = inode->i_private;
  92
  93                 if (!atomic_inc_not_zero(&clnt->cl_count)) {
  94                         seq_release(inode, filp);
  95                         ret = -EINVAL;
  96                 }
  97         }
  98
  99         return ret;
 100 }
 101
 102 static int
 103 tasks_release(struct inode *inode, struct file *filp)
 104 {
 105         struct seq_file *seq = filp->private_data;
 106         struct rpc_clnt *clnt = seq->private;
 107
 108         rpc_release_client(clnt);
 109         return seq_release(inode, filp);
 110 }
 111
 112 static const struct file_operations tasks_fops = {
 113         .owner          = THIS_MODULE,
 114         .open           = tasks_open,
 115         .read           = seq_read,
 116         .llseek         = seq_lseek,
 117         .release        = tasks_release,
 118 };
 119
 120 void
 121 rpc_clnt_debugfs_register(struct rpc_clnt *clnt)
 122 {
 123         int len;
 124         char name[24]; /* enough for "../../rpc_xprt/ + 8 hex digits + NULL */
 125         struct rpc_xprt *xprt;
 126
 127         len = snprintf(name, sizeof(name), "%x", clnt->cl_clid);
 128         if (len >= sizeof(name))
 129                 return;
 130
 131         /* make the per-client dir */
 132         clnt->cl_debugfs = debugfs_create_dir(name, rpc_clnt_dir);
 133
 134         /* make tasks file */
 135         debugfs_create_file("tasks", S_IFREG | 0400, clnt->cl_debugfs, clnt,
 136                             &tasks_fops);
 137
 138         rcu_read_lock();
 139         xprt = rcu_dereference(clnt->cl_xprt);
 140         /* no "debugfs" dentry? Don't bother with the symlink. */
 141         if (IS_ERR_OR_NULL(xprt->debugfs)) {
 142                 rcu_read_unlock();
 143                 return;
 144         }
 145         len = snprintf(name, sizeof(name), "../../rpc_xprt/%s",
 146                         xprt->debugfs->d_name.name);
 147         rcu_read_unlock();
 148
 149         if (len >= sizeof(name))
 150                 goto out_err;
 151
 152         debugfs_create_symlink("xprt", clnt->cl_debugfs, name);
 153
 154         return;
 155 out_err:
 156         debugfs_remove_recursive(clnt->cl_debugfs);
 157         clnt->cl_debugfs = NULL;
 158 }
 159
 160 void
 161 rpc_clnt_debugfs_unregister(struct rpc_clnt *clnt)
 162 {
 163         debugfs_remove_recursive(clnt->cl_debugfs);
 164         clnt->cl_debugfs = NULL;
 165 }
 166
 167 static int
 168 xprt_info_show(struct seq_file *f, void *v)
 169 {
 170         struct rpc_xprt *xprt = f->private;
 171
 172         seq_printf(f, "netid: %s\n", xprt->address_strings[RPC_DISPLAY_NETID]);
 173         seq_printf(f, "addr:  %s\n", xprt->address_strings[RPC_DISPLAY_ADDR]);
 174         seq_printf(f, "port:  %s\n", xprt->address_strings[RPC_DISPLAY_PORT]);
 175         seq_printf(f, "state: 0x%lx\n", xprt->state);
 176         return 0;
 177 }
 178
 179 static int
 180 xprt_info_open(struct inode *inode, struct file *filp)
 181 {
 182         int ret;
 183         struct rpc_xprt *xprt = inode->i_private;
 184
 185         ret = single_open(filp, xprt_info_show, xprt);
 186
 187         if (!ret) {
 188                 if (!xprt_get(xprt)) {
 189                         single_release(inode, filp);
 190                         ret = -EINVAL;
 191                 }
 192         }
 193         return ret;
 194 }
 195
 196 static int
 197 xprt_info_release(struct inode *inode, struct file *filp)
 198 {
 199         struct rpc_xprt *xprt = inode->i_private;
 200
 201         xprt_put(xprt);
 202         return single_release(inode, filp);
 203 }
 204
 205 static const struct file_operations xprt_info_fops = {
 206         .owner          = THIS_MODULE,
 207         .open           = xprt_info_open,
 208         .read           = seq_read,
 209         .llseek         = seq_lseek,
 210         .release        = xprt_info_release,
 211 };
 212
 213 void
 214 rpc_xprt_debugfs_register(struct rpc_xprt *xprt)
 215 {
 216         int len, id;
 217         static atomic_t cur_id;
 218         char            name[9]; /* 8 hex digits + NULL term */
 219
 220         id = (unsigned int)atomic_inc_return(&cur_id);
 221
 222         len = snprintf(name, sizeof(name), "%x", id);
 223         if (len >= sizeof(name))
 224                 return;
 225
 226         /* make the per-client dir */
 227         xprt->debugfs = debugfs_create_dir(name, rpc_xprt_dir);
 228
 229         /* make tasks file */
 230         debugfs_create_file("info", S_IFREG | 0400, xprt->debugfs, xprt,
 231                             &xprt_info_fops);
 232
 233         atomic_set(&xprt->inject_disconnect, rpc_inject_disconnect);
 234 }
 235
 236 void
 237 rpc_xprt_debugfs_unregister(struct rpc_xprt *xprt)
 238 {
 239         debugfs_remove_recursive(xprt->debugfs);
 240         xprt->debugfs = NULL;
 241 }
 242
 243 static int
 244 fault_open(struct inode *inode, struct file *filp)
 245 {
 246         filp->private_data = kmalloc(128, GFP_KERNEL);
 247         if (!filp->private_data)
 248                 return -ENOMEM;
 249         return 0;
 250 }
 251
 252 static int
 253 fault_release(struct inode *inode, struct file *filp)
 254 {
 255         kfree(filp->private_data);
 256         return 0;
 257 }
 258
 259 static ssize_t
 260 fault_disconnect_read(struct file *filp, char __user *user_buf,
 261                       size_t len, loff_t *offset)
 262 {
 263         char *buffer = (char *)filp->private_data;
 264         size_t size;
 265
 266         size = sprintf(buffer, "%u\n", rpc_inject_disconnect);
 267         return simple_read_from_buffer(user_buf, len, offset, buffer, size);
 268 }
 269
 270 static ssize_t
 271 fault_disconnect_write(struct file *filp, const char __user *user_buf,
 272                        size_t len, loff_t *offset)
 273 {
 274         char buffer[16];
 275
 276         if (len >= sizeof(buffer))
 277                 len = sizeof(buffer) - 1;
 278         if (copy_from_user(buffer, user_buf, len))
 279                 return -EFAULT;
 280         buffer[len] = '\0';
 281         if (kstrtouint(buffer, 10, &rpc_inject_disconnect))
 282                 return -EINVAL;
 283         return len;
 284 }
 285
 286 static const struct file_operations fault_disconnect_fops = {
 287         .owner          = THIS_MODULE,
 288         .open           = fault_open,
 289         .read           = fault_disconnect_read,
 290         .write          = fault_disconnect_write,
 291         .release        = fault_release,
 292 };
 293
 294 void __exit
 295 sunrpc_debugfs_exit(void)
 296 {
 297         debugfs_remove_recursive(topdir);
 298         topdir = NULL;
 299         rpc_clnt_dir = NULL;
 300         rpc_xprt_dir = NULL;
 301 }
 302
 303 void __init
 304 sunrpc_debugfs_init(void)
 305 {
 306         struct dentry *rpc_fault_dir;
 307
 308         topdir = debugfs_create_dir("sunrpc", NULL);
 309
 310         rpc_clnt_dir = debugfs_create_dir("rpc_clnt", topdir);
 311
 312         rpc_xprt_dir = debugfs_create_dir("rpc_xprt", topdir);
 313
 314         rpc_fault_dir = debugfs_create_dir("inject_fault", topdir);
 315
 316         debugfs_create_file("disconnect", S_IFREG | 0400, rpc_fault_dir, NULL,
 317                             &fault_disconnect_fops);
 318 }