net/sunrpc/debugfs.c

   1 /**
   2  * debugfs interface for sunrpc
   3  *
   4  * (c) 2014 Jeff Layton <jlayton@primarydata.com>
   5  */
   6
   7 #include <linux/debugfs.h>
   8 #include <linux/sunrpc/sched.h>
   9 #include <linux/sunrpc/clnt.h>
  10 #include "netns.h"
  11
  12 static struct dentry *topdir;
  13 static struct dentry *rpc_clnt_dir;
  14 static struct dentry *rpc_xprt_dir;
  15
  16 struct rpc_clnt_iter {
  17         struct rpc_clnt *clnt;
  18         loff_t          pos;
  19 };
  20
  21 static int
  22 tasks_show(struct seq_file *f, void *v)
  23 {
  24         u32 xid = 0;
  25         struct rpc_task *task = v;
  26         struct rpc_clnt *clnt = task->tk_client;
  27         const char *rpc_waitq = "none";
  28
  29         if (RPC_IS_QUEUED(task))
  30                 rpc_waitq = rpc_qname(task->tk_waitqueue);
  31
  32         if (task->tk_rqstp)
  33                 xid = be32_to_cpu(task->tk_rqstp->rq_xid);
  34
  35         seq_printf(f, "%5u %04x %6d 0x%x 0x%x %8ld %ps %sv%u %s a:%ps q:%s\n",
  36                 task->tk_pid, task->tk_flags, task->tk_status,
  37                 clnt->cl_clid, xid, task->tk_timeout, task->tk_ops,
  38                 clnt->cl_program->name, clnt->cl_vers, rpc_proc_name(task),
  39                 task->tk_action, rpc_waitq);
  40         return 0;
  41 }
  42
  43 static void *
  44 tasks_start(struct seq_file *f, loff_t *ppos)
  45         __acquires(&clnt->cl_lock)
  46 {
  47         struct rpc_clnt_iter *iter = f->private;
  48         loff_t pos = *ppos;
  49         struct rpc_clnt *clnt = iter->clnt;
  50         struct rpc_task *task;
  51
  52         iter->pos = pos + 1;
  53         spin_lock(&clnt->cl_lock);
  54         list_for_each_entry(task, &clnt->cl_tasks, tk_task)
  55                 if (pos-- == 0)
  56                         return task;
  57         return NULL;
  58 }
  59
  60 static void *
  61 tasks_next(struct seq_file *f, void *v, loff_t *pos)
  62 {
  63         struct rpc_clnt_iter *iter = f->private;
  64         struct rpc_clnt *clnt = iter->clnt;
  65         struct rpc_task *task = v;
  66         struct list_head *next = task->tk_task.next;
  67
  68         ++iter->pos;
  69         ++*pos;
  70
  71         /* If there's another task on list, return it */
  72         if (next == &clnt->cl_tasks)
  73                 return NULL;
  74         return list_entry(next, struct rpc_task, tk_task);
  75 }
  76
  77 static void
  78 tasks_stop(struct seq_file *f, void *v)
  79         __releases(&clnt->cl_lock)
  80 {
  81         struct rpc_clnt_iter *iter = f->private;
  82         struct rpc_clnt *clnt = iter->clnt;
  83
  84         spin_unlock(&clnt->cl_lock);
  85 }
  86
  87 static const struct seq_operations tasks_seq_operations = {
  88         .start  = tasks_start,
  89         .next   = tasks_next,
  90         .stop   = tasks_stop,
  91         .show   = tasks_show,
  92 };
  93
  94 static int tasks_open(struct inode *inode, struct file *filp)
  95 {
  96         int ret = seq_open_private(filp, &tasks_seq_operations,
  97                                         sizeof(struct rpc_clnt_iter));
  98
  99         if (!ret) {
 100                 struct seq_file *seq = filp->private_data;
 101                 struct rpc_clnt_iter *iter = seq->private;
 102
 103                 iter->clnt = inode->i_private;
 104
 105                 if (!atomic_inc_not_zero(&iter->clnt->cl_count)) {
 106                         seq_release_private(inode, filp);
 107                         ret = -EINVAL;
 108                 }
 109         }
 110
 111         return ret;
 112 }
 113
 114 static int
 115 tasks_release(struct inode *inode, struct file *filp)
 116 {
 117         struct seq_file *seq = filp->private_data;
 118         struct rpc_clnt_iter *iter = seq->private;
 119
 120         rpc_release_client(iter->clnt);
 121         return seq_release_private(inode, filp);
 122 }
 123
 124 static const struct file_operations tasks_fops = {
 125         .owner          = THIS_MODULE,
 126         .open           = tasks_open,
 127         .read           = seq_read,
 128         .llseek         = seq_lseek,
 129         .release        = tasks_release,
 130 };
 131
 132 int
 133 rpc_clnt_debugfs_register(struct rpc_clnt *clnt)
 134 {
 135         int len, err;
 136         char name[24]; /* enough for "../../rpc_xprt/ + 8 hex digits + NULL */
 137
 138         /* Already registered? */
 139         if (clnt->cl_debugfs)
 140                 return 0;
 141
 142         len = snprintf(name, sizeof(name), "%x", clnt->cl_clid);
 143         if (len >= sizeof(name))
 144                 return -EINVAL;
 145
 146         /* make the per-client dir */
 147         clnt->cl_debugfs = debugfs_create_dir(name, rpc_clnt_dir);
 148         if (!clnt->cl_debugfs)
 149                 return -ENOMEM;
 150
 151         /* make tasks file */
 152         err = -ENOMEM;
 153         if (!debugfs_create_file("tasks", S_IFREG | S_IRUSR, clnt->cl_debugfs,
 154                                  clnt, &tasks_fops))
 155                 goto out_err;
 156
 157         err = -EINVAL;
 158         rcu_read_lock();
 159         len = snprintf(name, sizeof(name), "../../rpc_xprt/%s",
 160                         rcu_dereference(clnt->cl_xprt)->debugfs->d_name.name);
 161         rcu_read_unlock();
 162         if (len >= sizeof(name))
 163                 goto out_err;
 164
 165         err = -ENOMEM;
 166         if (!debugfs_create_symlink("xprt", clnt->cl_debugfs, name))
 167                 goto out_err;
 168
 169         return 0;
 170 out_err:
 171         debugfs_remove_recursive(clnt->cl_debugfs);
 172         clnt->cl_debugfs = NULL;
 173         return err;
 174 }
 175
 176 void
 177 rpc_clnt_debugfs_unregister(struct rpc_clnt *clnt)
 178 {
 179         debugfs_remove_recursive(clnt->cl_debugfs);
 180         clnt->cl_debugfs = NULL;
 181 }
 182
 183 static int
 184 xprt_info_show(struct seq_file *f, void *v)
 185 {
 186         struct rpc_xprt *xprt = f->private;
 187
 188         seq_printf(f, "netid: %s\n", xprt->address_strings[RPC_DISPLAY_NETID]);
 189         seq_printf(f, "addr:  %s\n", xprt->address_strings[RPC_DISPLAY_ADDR]);
 190         seq_printf(f, "port:  %s\n", xprt->address_strings[RPC_DISPLAY_PORT]);
 191         seq_printf(f, "state: 0x%lx\n", xprt->state);
 192         return 0;
 193 }
 194
 195 static int
 196 xprt_info_open(struct inode *inode, struct file *filp)
 197 {
 198         int ret;
 199         struct rpc_xprt *xprt = inode->i_private;
 200
 201         ret = single_open(filp, xprt_info_show, xprt);
 202
 203         if (!ret) {
 204                 if (!xprt_get(xprt)) {
 205                         single_release(inode, filp);
 206                         ret = -EINVAL;
 207                 }
 208         }
 209         return ret;
 210 }
 211
 212 static int
 213 xprt_info_release(struct inode *inode, struct file *filp)
 214 {
 215         struct rpc_xprt *xprt = inode->i_private;
 216
 217         xprt_put(xprt);
 218         return single_release(inode, filp);
 219 }
 220
 221 static const struct file_operations xprt_info_fops = {
 222         .owner          = THIS_MODULE,
 223         .open           = xprt_info_open,
 224         .read           = seq_read,
 225         .llseek         = seq_lseek,
 226         .release        = xprt_info_release,
 227 };
 228
 229 int
 230 rpc_xprt_debugfs_register(struct rpc_xprt *xprt)
 231 {
 232         int len, id;
 233         static atomic_t cur_id;
 234         char            name[9]; /* 8 hex digits + NULL term */
 235
 236         id = (unsigned int)atomic_inc_return(&cur_id);
 237
 238         len = snprintf(name, sizeof(name), "%x", id);
 239         if (len >= sizeof(name))
 240                 return -EINVAL;
 241
 242         /* make the per-client dir */
 243         xprt->debugfs = debugfs_create_dir(name, rpc_xprt_dir);
 244         if (!xprt->debugfs)
 245                 return -ENOMEM;
 246
 247         /* make tasks file */
 248         if (!debugfs_create_file("info", S_IFREG | S_IRUSR, xprt->debugfs,
 249                                  xprt, &xprt_info_fops)) {
 250                 debugfs_remove_recursive(xprt->debugfs);
 251                 xprt->debugfs = NULL;
 252                 return -ENOMEM;
 253         }
 254
 255         return 0;
 256 }
 257
 258 void
 259 rpc_xprt_debugfs_unregister(struct rpc_xprt *xprt)
 260 {
 261         debugfs_remove_recursive(xprt->debugfs);
 262         xprt->debugfs = NULL;
 263 }
 264
 265 void __exit
 266 sunrpc_debugfs_exit(void)
 267 {
 268         debugfs_remove_recursive(topdir);
 269 }
 270
 271 int __init
 272 sunrpc_debugfs_init(void)
 273 {
 274         topdir = debugfs_create_dir("sunrpc", NULL);
 275         if (!topdir)
 276                 goto out;
 277
 278         rpc_clnt_dir = debugfs_create_dir("rpc_clnt", topdir);
 279         if (!rpc_clnt_dir)
 280                 goto out_remove;
 281
 282         rpc_xprt_dir = debugfs_create_dir("rpc_xprt", topdir);
 283         if (!rpc_xprt_dir)
 284                 goto out_remove;
 285
 286         return 0;
 287 out_remove:
 288         debugfs_remove_recursive(topdir);
 289         topdir = NULL;
 290 out:
 291         return -ENOMEM;
 292 }