kernel/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 void
 133 rpc_clnt_debugfs_register(struct rpc_clnt *clnt)
 134 {
 135         int len;
 136         char name[24]; /* enough for "../../rpc_xprt/ + 8 hex digits + NULL */
 137         struct rpc_xprt *xprt;
 138
 139         /* Already registered? */
 140         if (clnt->cl_debugfs || !rpc_clnt_dir)
 141                 return;
 142
 143         len = snprintf(name, sizeof(name), "%x", clnt->cl_clid);
 144         if (len >= sizeof(name))
 145                 return;
 146
 147         /* make the per-client dir */
 148         clnt->cl_debugfs = debugfs_create_dir(name, rpc_clnt_dir);
 149         if (!clnt->cl_debugfs)
 150                 return;
 151
 152         /* make tasks file */
 153         if (!debugfs_create_file("tasks", S_IFREG | S_IRUSR, clnt->cl_debugfs,
 154                                  clnt, &tasks_fops))
 155                 goto out_err;
 156
 157         rcu_read_lock();
 158         xprt = rcu_dereference(clnt->cl_xprt);
 159         /* no "debugfs" dentry? Don't bother with the symlink. */
 160         if (!xprt->debugfs) {
 161                 rcu_read_unlock();
 162                 return;
 163         }
 164         len = snprintf(name, sizeof(name), "../../rpc_xprt/%s",
 165                         xprt->debugfs->d_name.name);
 166         rcu_read_unlock();
 167
 168         if (len >= sizeof(name))
 169                 goto out_err;
 170
 171         if (!debugfs_create_symlink("xprt", clnt->cl_debugfs, name))
 172                 goto out_err;
 173
 174         return;
 175 out_err:
 176         debugfs_remove_recursive(clnt->cl_debugfs);
 177         clnt->cl_debugfs = NULL;
 178 }
 179
 180 void
 181 rpc_clnt_debugfs_unregister(struct rpc_clnt *clnt)
 182 {
 183         debugfs_remove_recursive(clnt->cl_debugfs);
 184         clnt->cl_debugfs = NULL;
 185 }
 186
 187 static int
 188 xprt_info_show(struct seq_file *f, void *v)
 189 {
 190         struct rpc_xprt *xprt = f->private;
 191
 192         seq_printf(f, "netid: %s\n", xprt->address_strings[RPC_DISPLAY_NETID]);
 193         seq_printf(f, "addr:  %s\n", xprt->address_strings[RPC_DISPLAY_ADDR]);
 194         seq_printf(f, "port:  %s\n", xprt->address_strings[RPC_DISPLAY_PORT]);
 195         seq_printf(f, "state: 0x%lx\n", xprt->state);
 196         return 0;
 197 }
 198
 199 static int
 200 xprt_info_open(struct inode *inode, struct file *filp)
 201 {
 202         int ret;
 203         struct rpc_xprt *xprt = inode->i_private;
 204
 205         ret = single_open(filp, xprt_info_show, xprt);
 206
 207         if (!ret) {
 208                 if (!xprt_get(xprt)) {
 209                         single_release(inode, filp);
 210                         ret = -EINVAL;
 211                 }
 212         }
 213         return ret;
 214 }
 215
 216 static int
 217 xprt_info_release(struct inode *inode, struct file *filp)
 218 {
 219         struct rpc_xprt *xprt = inode->i_private;
 220
 221         xprt_put(xprt);
 222         return single_release(inode, filp);
 223 }
 224
 225 static const struct file_operations xprt_info_fops = {
 226         .owner          = THIS_MODULE,
 227         .open           = xprt_info_open,
 228         .read           = seq_read,
 229         .llseek         = seq_lseek,
 230         .release        = xprt_info_release,
 231 };
 232
 233 void
 234 rpc_xprt_debugfs_register(struct rpc_xprt *xprt)
 235 {
 236         int len, id;
 237         static atomic_t cur_id;
 238         char            name[9]; /* 8 hex digits + NULL term */
 239
 240         if (!rpc_xprt_dir)
 241                 return;
 242
 243         id = (unsigned int)atomic_inc_return(&cur_id);
 244
 245         len = snprintf(name, sizeof(name), "%x", id);
 246         if (len >= sizeof(name))
 247                 return;
 248
 249         /* make the per-client dir */
 250         xprt->debugfs = debugfs_create_dir(name, rpc_xprt_dir);
 251         if (!xprt->debugfs)
 252                 return;
 253
 254         /* make tasks file */
 255         if (!debugfs_create_file("info", S_IFREG | S_IRUSR, xprt->debugfs,
 256                                  xprt, &xprt_info_fops)) {
 257                 debugfs_remove_recursive(xprt->debugfs);
 258                 xprt->debugfs = NULL;
 259         }
 260 }
 261
 262 void
 263 rpc_xprt_debugfs_unregister(struct rpc_xprt *xprt)
 264 {
 265         debugfs_remove_recursive(xprt->debugfs);
 266         xprt->debugfs = NULL;
 267 }
 268
 269 void __exit
 270 sunrpc_debugfs_exit(void)
 271 {
 272         debugfs_remove_recursive(topdir);
 273         topdir = NULL;
 274         rpc_clnt_dir = NULL;
 275         rpc_xprt_dir = NULL;
 276 }
 277
 278 void __init
 279 sunrpc_debugfs_init(void)
 280 {
 281         topdir = debugfs_create_dir("sunrpc", NULL);
 282         if (!topdir)
 283                 return;
 284
 285         rpc_clnt_dir = debugfs_create_dir("rpc_clnt", topdir);
 286         if (!rpc_clnt_dir)
 287                 goto out_remove;
 288
 289         rpc_xprt_dir = debugfs_create_dir("rpc_xprt", topdir);
 290         if (!rpc_xprt_dir)
 291                 goto out_remove;
 292
 293         return;
 294 out_remove:
 295         debugfs_remove_recursive(topdir);
 296         topdir = NULL;
 297         rpc_clnt_dir = NULL;
 298 }