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LU-11986 lnet: properly cleanup lnet debugfs files
[fs/lustre-release.git] / libcfs / libcfs / module.c
index 6170124..de792a9 100644 (file)
  *
  * You should have received a copy of the GNU General Public License
  * version 2 along with this program; If not, see
- * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
- *
- * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
- * CA 95054 USA or visit www.sun.com if you need additional information or
- * have any questions.
+ * http://www.gnu.org/licenses/gpl-2.0.html
  *
  * GPL HEADER END
  */
  * Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
  * Use is subject to license terms.
  *
- * Copyright (c) 2012, 2014, Intel Corporation.
+ * Copyright (c) 2012, 2017, Intel Corporation.
  */
 /*
  * This file is part of Lustre, http://www.lustre.org/
  * Lustre is a trademark of Sun Microsystems, Inc.
  */
+#include <linux/miscdevice.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/string.h>
+#include <linux/stat.h>
+#include <linux/errno.h>
+#include <linux/unistd.h>
+#include <net/sock.h>
+#include <linux/uio.h>
+#include <linux/uaccess.h>
+
+#include <linux/fs.h>
+#include <linux/file.h>
+#include <linux/list.h>
+
+#include <linux/sysctl.h>
+#include <linux/debugfs.h>
+#include <asm/div64.h>
 
 #define DEBUG_SUBSYSTEM S_LNET
 
 #include <libcfs/libcfs.h>
 #include <libcfs/libcfs_crypto.h>
 #include <lnet/lib-lnet.h>
+#include "tracefile.h"
+
+static struct dentry *lnet_debugfs_root;
+
+BLOCKING_NOTIFIER_HEAD(libcfs_ioctl_list);
+EXPORT_SYMBOL(libcfs_ioctl_list);
 
-static void
-kportal_memhog_free (struct libcfs_device_userstate *ldu)
+int libcfs_ioctl(unsigned long cmd, void __user *uparam)
 {
-       struct page **level0p = &ldu->ldu_memhog_root_page;
-       struct page **level1p;
-       struct page **level2p;
-       int           count1;
-       int           count2;
-
-       if (*level0p != NULL) {
-               level1p = (struct page **)page_address(*level0p);
-               count1 = 0;
-
-               while (count1 < PAGE_CACHE_SIZE/sizeof(struct page *) &&
-                      *level1p != NULL) {
-
-                       level2p = (struct page **)page_address(*level1p);
-                       count2 = 0;
-
-                       while (count2 < PAGE_CACHE_SIZE/sizeof(struct page *) &&
-                              *level2p != NULL) {
-
-                               __free_page(*level2p);
-                               ldu->ldu_memhog_pages--;
-                               level2p++;
-                               count2++;
-                       }
-
-                       __free_page(*level1p);
-                       ldu->ldu_memhog_pages--;
-                       level1p++;
-                       count1++;
-               }
+       struct libcfs_ioctl_data *data = NULL;
+       struct libcfs_ioctl_hdr  *hdr;
+       int                       err;
+       ENTRY;
 
-               __free_page(*level0p);
-               ldu->ldu_memhog_pages--;
+       /* 'cmd' and permissions get checked in our arch-specific caller */
+       err = libcfs_ioctl_getdata(&hdr, uparam);
+       if (err != 0) {
+               CDEBUG_LIMIT(D_ERROR,
+                            "libcfs ioctl: data header error %d\n", err);
+               RETURN(err);
+       }
 
-               *level0p = NULL;
+       if (hdr->ioc_version == LIBCFS_IOCTL_VERSION) {
+               /* The libcfs_ioctl_data_adjust() function performs adjustment
+                * operations on the libcfs_ioctl_data structure to make
+                * it usable by the code.  This doesn't need to be called
+                * for new data structures added. */
+               data = container_of(hdr, struct libcfs_ioctl_data, ioc_hdr);
+               err = libcfs_ioctl_data_adjust(data);
+               if (err != 0)
+                       GOTO(out, err);
        }
 
-       LASSERT(ldu->ldu_memhog_pages == 0);
+       CDEBUG(D_IOCTL, "libcfs ioctl cmd %lu\n", cmd);
+       switch (cmd) {
+       case IOC_LIBCFS_CLEAR_DEBUG:
+               libcfs_debug_clear_buffer();
+               break;
+       case IOC_LIBCFS_MARK_DEBUG:
+               if (data == NULL ||
+                   data->ioc_inlbuf1 == NULL ||
+                   data->ioc_inlbuf1[data->ioc_inllen1 - 1] != '\0')
+                       GOTO(out, err = -EINVAL);
+
+               libcfs_debug_mark_buffer(data->ioc_inlbuf1);
+               break;
+
+       default:
+               err = blocking_notifier_call_chain(&libcfs_ioctl_list,
+                                                  cmd, hdr);
+               if (!(err & NOTIFY_STOP_MASK))
+                       /* No-one claimed the ioctl */
+                       err = -EINVAL;
+               else
+                       err = notifier_to_errno(err);
+               if (!err)
+                       if (copy_to_user(uparam, hdr, hdr->ioc_len))
+                               err = -EFAULT;
+               break;
+       }
+out:
+       LIBCFS_FREE(hdr, hdr->ioc_len);
+       RETURN(err);
 }
 
-static int
-kportal_memhog_alloc(struct libcfs_device_userstate *ldu, int npages,
-                    gfp_t flags)
+int lprocfs_call_handler(void *data, int write, loff_t *ppos,
+                        void __user *buffer, size_t *lenp,
+                        int (*handler)(void *data, int write, loff_t pos,
+                                       void __user *buffer, int len))
 {
-       struct page **level0p;
-       struct page **level1p;
-       struct page **level2p;
-       int           count1;
-       int           count2;
-
-       LASSERT(ldu->ldu_memhog_pages == 0);
-       LASSERT(ldu->ldu_memhog_root_page == NULL);
+       int rc = handler(data, write, *ppos, buffer, *lenp);
 
-       if (npages < 0)
-               return -EINVAL;
+       if (rc < 0)
+               return rc;
 
-       if (npages == 0)
-               return 0;
+       if (write) {
+               *ppos += *lenp;
+       } else {
+               *lenp = rc;
+               *ppos += rc;
+       }
+       return 0;
+}
+EXPORT_SYMBOL(lprocfs_call_handler);
 
-       level0p = &ldu->ldu_memhog_root_page;
-       *level0p = alloc_page(flags);
-       if (*level0p == NULL)
-               return -ENOMEM;
-       ldu->ldu_memhog_pages++;
+static int __proc_dobitmasks(void *data, int write,
+                            loff_t pos, void __user *buffer, int nob)
+{
+       const int     tmpstrlen = 512;
+       char         *tmpstr;
+       int           rc;
+       unsigned int *mask = data;
+       int           is_subsys = (mask == &libcfs_subsystem_debug) ? 1 : 0;
+       int           is_printk = (mask == &libcfs_printk) ? 1 : 0;
+
+       rc = cfs_trace_allocate_string_buffer(&tmpstr, tmpstrlen);
+       if (rc < 0)
+               return rc;
+
+       if (!write) {
+               libcfs_debug_mask2str(tmpstr, tmpstrlen, *mask, is_subsys);
+               rc = strlen(tmpstr);
+
+               if (pos >= rc) {
+                       rc = 0;
+               } else {
+                       rc = cfs_trace_copyout_string(buffer, nob,
+                                                     tmpstr + pos, "\n");
+               }
+       } else {
+               rc = cfs_trace_copyin_string(tmpstr, tmpstrlen, buffer, nob);
+               if (rc < 0) {
+                       kfree(tmpstr);
+                       return rc;
+               }
 
-       level1p = (struct page **)page_address(*level0p);
-       count1 = 0;
-       memset(level1p, 0, PAGE_CACHE_SIZE);
+               rc = libcfs_debug_str2mask(mask, tmpstr, is_subsys);
+               /* Always print LBUG/LASSERT to console, so keep this mask */
+               if (is_printk)
+                       *mask |= D_EMERG;
+       }
 
-       while (ldu->ldu_memhog_pages < npages &&
-              count1 < PAGE_CACHE_SIZE/sizeof(struct page *)) {
+       kfree(tmpstr);
+       return rc;
+}
 
-               if (signal_pending(current))
-                       return -EINTR;
+static int proc_dobitmasks(struct ctl_table *table, int write,
+                          void __user *buffer, size_t *lenp, loff_t *ppos)
+{
+       return lprocfs_call_handler(table->data, write, ppos, buffer, lenp,
+                                   __proc_dobitmasks);
+}
 
-               *level1p = alloc_page(flags);
-               if (*level1p == NULL)
-                       return -ENOMEM;
-               ldu->ldu_memhog_pages++;
+static int min_watchdog_ratelimit;             /* disable ratelimiting */
+static int max_watchdog_ratelimit = (24*60*60); /* limit to once per day */
 
-               level2p = (struct page **)page_address(*level1p);
-               count2 = 0;
-               memset(level2p, 0, PAGE_CACHE_SIZE);
+static int __proc_dump_kernel(void *data, int write,
+                             loff_t pos, void __user *buffer, int nob)
+{
+       if (!write)
+               return 0;
 
-               while (ldu->ldu_memhog_pages < npages &&
-                      count2 < PAGE_CACHE_SIZE/sizeof(struct page *)) {
+       return cfs_trace_dump_debug_buffer_usrstr(buffer, nob);
+}
 
-                       if (signal_pending(current))
-                               return -EINTR;
+static int proc_dump_kernel(struct ctl_table *table, int write,
+                           void __user *buffer, size_t *lenp, loff_t *ppos)
+{
+       return lprocfs_call_handler(table->data, write, ppos, buffer, lenp,
+                                   __proc_dump_kernel);
+}
 
-                       *level2p = alloc_page(flags);
-                       if (*level2p == NULL)
-                               return -ENOMEM;
-                       ldu->ldu_memhog_pages++;
+static int __proc_daemon_file(void *data, int write,
+                             loff_t pos, void __user *buffer, int nob)
+{
+       if (!write) {
+               int len = strlen(cfs_tracefile);
 
-                       level2p++;
-                       count2++;
-               }
+               if (pos >= len)
+                       return 0;
 
-               level1p++;
-               count1++;
+               return cfs_trace_copyout_string(buffer, nob,
+                                               cfs_tracefile + pos, "\n");
        }
 
-       return 0;
+       return cfs_trace_daemon_command_usrstr(buffer, nob);
 }
 
-/* called when opening /dev/device */
-static int libcfs_psdev_open(unsigned long flags, void *args)
+static int proc_daemon_file(struct ctl_table *table, int write,
+                           void __user *buffer, size_t *lenp, loff_t *ppos)
 {
-       struct libcfs_device_userstate *ldu;
-       ENTRY;
+       return lprocfs_call_handler(table->data, write, ppos, buffer, lenp,
+                                   __proc_daemon_file);
+}
 
-       try_module_get(THIS_MODULE);
+static int libcfs_force_lbug(struct ctl_table *table, int write,
+                            void __user *buffer,
+                            size_t *lenp, loff_t *ppos)
+{
+       if (write)
+               LBUG();
+       return 0;
+}
 
-       LIBCFS_ALLOC(ldu, sizeof(*ldu));
-       if (ldu != NULL) {
-               ldu->ldu_memhog_pages = 0;
-               ldu->ldu_memhog_root_page = NULL;
-       }
-       *(struct libcfs_device_userstate **)args = ldu;
+static int proc_fail_loc(struct ctl_table *table, int write,
+                        void __user *buffer, size_t *lenp, loff_t *ppos)
+{
+       int rc;
+       long old_fail_loc = cfs_fail_loc;
 
-       RETURN(0);
+       rc = proc_doulongvec_minmax(table, write, buffer, lenp, ppos);
+       if (old_fail_loc != cfs_fail_loc)
+               wake_up(&cfs_race_waitq);
+       return rc;
 }
 
-/* called when closing /dev/device */
-static int libcfs_psdev_release(unsigned long flags, void *args)
+static int __proc_cpt_table(void *data, int write,
+                           loff_t pos, void __user *buffer, int nob)
 {
-       struct libcfs_device_userstate *ldu;
-       ENTRY;
+       char *buf = NULL;
+       int   len = 4096;
+       int   rc  = 0;
+
+       if (write)
+               return -EPERM;
+
+       LASSERT(cfs_cpt_table != NULL);
 
-       ldu = (struct libcfs_device_userstate *)args;
-       if (ldu != NULL) {
-               kportal_memhog_free(ldu);
-               LIBCFS_FREE(ldu, sizeof(*ldu));
+       while (1) {
+               LIBCFS_ALLOC(buf, len);
+               if (buf == NULL)
+                       return -ENOMEM;
+
+               rc = cfs_cpt_table_print(cfs_cpt_table, buf, len);
+               if (rc >= 0)
+                       break;
+
+               if (rc == -EFBIG) {
+                       LIBCFS_FREE(buf, len);
+                       len <<= 1;
+                       continue;
+               }
+               goto out;
        }
 
-       module_put(THIS_MODULE);
-       RETURN(0);
+       if (pos >= rc) {
+               rc = 0;
+               goto out;
+       }
+
+       rc = cfs_trace_copyout_string(buffer, nob, buf + pos, NULL);
+out:
+       if (buf != NULL)
+               LIBCFS_FREE(buf, len);
+       return rc;
 }
 
-static DECLARE_RWSEM(ioctl_list_sem);
-static LIST_HEAD(ioctl_list);
+static int proc_cpt_table(struct ctl_table *table, int write,
+                         void __user *buffer, size_t *lenp, loff_t *ppos)
+{
+       return lprocfs_call_handler(table->data, write, ppos, buffer, lenp,
+                                   __proc_cpt_table);
+}
 
-int libcfs_register_ioctl(struct libcfs_ioctl_handler *hand)
+static int __proc_cpt_distance(void *data, int write,
+                              loff_t pos, void __user *buffer, int nob)
 {
-       int rc = 0;
+       char *buf = NULL;
+       int   len = 4096;
+       int   rc  = 0;
+
+       if (write)
+               return -EPERM;
+
+       LASSERT(cfs_cpt_table != NULL);
 
-       down_write(&ioctl_list_sem);
-       if (!list_empty(&hand->item))
-               rc = -EBUSY;
-       else
-               list_add_tail(&hand->item, &ioctl_list);
-       up_write(&ioctl_list_sem);
+       while (1) {
+               LIBCFS_ALLOC(buf, len);
+               if (buf == NULL)
+                       return -ENOMEM;
+
+               rc = cfs_cpt_distance_print(cfs_cpt_table, buf, len);
+               if (rc >= 0)
+                       break;
+
+               if (rc == -EFBIG) {
+                       LIBCFS_FREE(buf, len);
+                       len <<= 1;
+                       continue;
+               }
+               goto out;
+       }
+
+       if (pos >= rc) {
+               rc = 0;
+               goto out;
+       }
 
+       rc = cfs_trace_copyout_string(buffer, nob, buf + pos, NULL);
+ out:
+       if (buf != NULL)
+               LIBCFS_FREE(buf, len);
        return rc;
 }
-EXPORT_SYMBOL(libcfs_register_ioctl);
 
-int libcfs_deregister_ioctl(struct libcfs_ioctl_handler *hand)
+static int proc_cpt_distance(struct ctl_table *table, int write,
+                            void __user *buffer, size_t *lenp, loff_t *ppos)
 {
-       int rc = 0;
+       return lprocfs_call_handler(table->data, write, ppos, buffer, lenp,
+                                    __proc_cpt_distance);
+}
 
-       down_write(&ioctl_list_sem);
-       if (list_empty(&hand->item))
-               rc = -ENOENT;
-       else
-               list_del_init(&hand->item);
-       up_write(&ioctl_list_sem);
+static struct ctl_table lnet_table[] = {
+       {
+               INIT_CTL_NAME
+               .procname       = "debug",
+               .data           = &libcfs_debug,
+               .maxlen         = sizeof(int),
+               .mode           = 0644,
+               .proc_handler   = &proc_dobitmasks,
+       },
+       {
+               INIT_CTL_NAME
+               .procname       = "subsystem_debug",
+               .data           = &libcfs_subsystem_debug,
+               .maxlen         = sizeof(int),
+               .mode           = 0644,
+               .proc_handler   = &proc_dobitmasks,
+       },
+       {
+               INIT_CTL_NAME
+               .procname       = "printk",
+               .data           = &libcfs_printk,
+               .maxlen         = sizeof(int),
+               .mode           = 0644,
+               .proc_handler   = &proc_dobitmasks,
+       },
+       {
+               INIT_CTL_NAME
+               .procname       = "cpu_partition_table",
+               .maxlen         = 128,
+               .mode           = 0444,
+               .proc_handler   = &proc_cpt_table,
+       },
+       {
+               INIT_CTL_NAME
+               .procname       = "cpu_partition_distance",
+               .maxlen         = 128,
+               .mode           = 0444,
+               .proc_handler   = &proc_cpt_distance,
+       },
+       {
+               INIT_CTL_NAME
+               .procname       = "debug_log_upcall",
+               .data           = lnet_debug_log_upcall,
+               .maxlen         = sizeof(lnet_debug_log_upcall),
+               .mode           = 0644,
+               .proc_handler   = &proc_dostring,
+       },
+       {
+               INIT_CTL_NAME
+               .procname       = "lnet_memused",
+               .data           = (int *)&libcfs_kmemory.counter,
+               .maxlen         = sizeof(int),
+               .mode           = 0444,
+               .proc_handler   = &proc_dointvec,
+       },
+       {
+               INIT_CTL_NAME
+               .procname       = "catastrophe",
+               .data           = &libcfs_catastrophe,
+               .maxlen         = sizeof(int),
+               .mode           = 0444,
+               .proc_handler   = &proc_dointvec,
+       },
+       {
+               INIT_CTL_NAME
+               .procname       = "dump_kernel",
+               .maxlen         = 256,
+               .mode           = 0200,
+               .proc_handler   = &proc_dump_kernel,
+       },
+       {
+               INIT_CTL_NAME
+               .procname       = "daemon_file",
+               .mode           = 0644,
+               .maxlen         = 256,
+               .proc_handler   = &proc_daemon_file,
+       },
+       {
+               INIT_CTL_NAME
+               .procname       = "watchdog_ratelimit",
+               .data           = &libcfs_watchdog_ratelimit,
+               .maxlen         = sizeof(int),
+               .mode           = 0644,
+               .proc_handler   = &proc_dointvec_minmax,
+               .extra1         = &min_watchdog_ratelimit,
+               .extra2         = &max_watchdog_ratelimit,
+       },
+       {
+               INIT_CTL_NAME
+               .procname       = "force_lbug",
+               .data           = NULL,
+               .maxlen         = 0,
+               .mode           = 0200,
+               .proc_handler   = &libcfs_force_lbug
+       },
+       {
+               INIT_CTL_NAME
+               .procname       = "fail_loc",
+               .data           = &cfs_fail_loc,
+               .maxlen         = sizeof(cfs_fail_loc),
+               .mode           = 0644,
+               .proc_handler   = &proc_fail_loc
+       },
+       {
+               INIT_CTL_NAME
+               .procname       = "fail_val",
+               .data           = &cfs_fail_val,
+               .maxlen         = sizeof(int),
+               .mode           = 0644,
+               .proc_handler   = &proc_dointvec
+       },
+       {
+               INIT_CTL_NAME
+               .procname       = "fail_err",
+               .data           = &cfs_fail_err,
+               .maxlen         = sizeof(cfs_fail_err),
+               .mode           = 0644,
+               .proc_handler   = &proc_dointvec,
+       },
+       {
+       }
+};
 
-       return rc;
-}
-EXPORT_SYMBOL(libcfs_deregister_ioctl);
+static const struct lnet_debugfs_symlink_def lnet_debugfs_symlinks[] = {
+       { .name         = "console_ratelimit",
+         .target       = "../../../module/libcfs/parameters/libcfs_console_ratelimit" },
+       { .name         = "debug_path",
+         .target       = "../../../module/libcfs/parameters/libcfs_debug_file_path" },
+       { .name         = "panic_on_lbug",
+         .target       = "../../../module/libcfs/parameters/libcfs_panic_on_lbug" },
+       { .name         = "console_backoff",
+         .target       = "../../../module/libcfs/parameters/libcfs_console_backoff" },
+       { .name         = "debug_mb",
+         .target       = "../../../module/libcfs/parameters/libcfs_debug_mb" },
+       { .name         = "console_min_delay_centisecs",
+         .target       = "../../../module/libcfs/parameters/libcfs_console_min_delay" },
+       { .name         = "console_max_delay_centisecs",
+         .target       = "../../../module/libcfs/parameters/libcfs_console_max_delay" },
+       { .name         = NULL },
+};
 
-static int libcfs_ioctl(struct cfs_psdev_file *pfile,
-                       unsigned long cmd, void __user *uparam)
+static ssize_t lnet_debugfs_read(struct file *filp, char __user *buf,
+                                size_t count, loff_t *ppos)
 {
-       struct libcfs_ioctl_data *data = NULL;
-       struct libcfs_ioctl_hdr  *hdr;
-       int                       err;
-       ENTRY;
+       struct ctl_table *table = filp->private_data;
+       ssize_t rc = -EINVAL;
 
-       /* 'cmd' and permissions get checked in our arch-specific caller */
-       err = libcfs_ioctl_getdata(&hdr, uparam);
-       if (err != 0) {
-               CDEBUG_LIMIT(D_ERROR,
-                            "libcfs ioctl: data header error %d\n", err);
-               RETURN(err);
+       if (table) {
+               rc = table->proc_handler(table, 0, buf, &count, ppos);
+               if (!rc)
+                       rc = count;
        }
 
-       if (hdr->ioc_version == LIBCFS_IOCTL_VERSION) {
-               /* The libcfs_ioctl_data_adjust() function performs adjustment
-                * operations on the libcfs_ioctl_data structure to make
-                * it usable by the code.  This doesn't need to be called
-                * for new data structures added. */
-               data = container_of(hdr, struct libcfs_ioctl_data, ioc_hdr);
-               err = libcfs_ioctl_data_adjust(data);
-               if (err != 0)
-                       GOTO(out, err);
+       return rc;
+}
+
+static ssize_t lnet_debugfs_write(struct file *filp, const char __user *buf,
+                                 size_t count, loff_t *ppos)
+{
+       struct ctl_table *table = filp->private_data;
+       ssize_t rc = -EINVAL;
+
+       if (table) {
+               rc = table->proc_handler(table, 1, (void __user *)buf, &count,
+                                        ppos);
+               if (!rc)
+                       rc = count;
        }
 
-       CDEBUG(D_IOCTL, "libcfs ioctl cmd %lu\n", cmd);
-       switch (cmd) {
-       case IOC_LIBCFS_CLEAR_DEBUG:
-               libcfs_debug_clear_buffer();
-               break;
-       /*
-        * case IOC_LIBCFS_PANIC:
-        * Handled in arch/cfs_module.c
-        */
-       case IOC_LIBCFS_MARK_DEBUG:
-               if (data == NULL ||
-                   data->ioc_inlbuf1 == NULL ||
-                   data->ioc_inlbuf1[data->ioc_inllen1 - 1] != '\0')
-                       GOTO(out, err = -EINVAL);
+       return rc;
+}
 
-               libcfs_debug_mark_buffer(data->ioc_inlbuf1);
-               break;
+static const struct file_operations lnet_debugfs_file_operations_rw = {
+       .open           = simple_open,
+       .read           = lnet_debugfs_read,
+       .write          = lnet_debugfs_write,
+       .llseek         = default_llseek,
+};
 
-       case IOC_LIBCFS_MEMHOG:
-               if (data == NULL)
-                       GOTO(out, err = -EINVAL);
+static const struct file_operations lnet_debugfs_file_operations_ro = {
+       .open           = simple_open,
+       .read           = lnet_debugfs_read,
+       .llseek         = default_llseek,
+};
 
-               if (pfile->private_data == NULL)
-                       GOTO(out, err = -EINVAL);
+static const struct file_operations lnet_debugfs_file_operations_wo = {
+       .open           = simple_open,
+       .write          = lnet_debugfs_write,
+       .llseek         = default_llseek,
+};
 
-               kportal_memhog_free(pfile->private_data);
-               err = kportal_memhog_alloc(pfile->private_data,
-                                          data->ioc_count, data->ioc_flags);
-               if (err != 0)
-                       kportal_memhog_free(pfile->private_data);
-               break;
+static const struct file_operations *lnet_debugfs_fops_select(umode_t mode)
+{
+       if (!(mode & S_IWUGO))
+               return &lnet_debugfs_file_operations_ro;
 
-       default: {
-               struct libcfs_ioctl_handler *hand;
+       if (!(mode & S_IRUGO))
+               return &lnet_debugfs_file_operations_wo;
 
-               err = -EINVAL;
-               down_read(&ioctl_list_sem);
-               list_for_each_entry(hand, &ioctl_list, item) {
-                       err = hand->handle_ioctl(cmd, hdr);
-                       if (err == -EINVAL)
-                               continue;
+       return &lnet_debugfs_file_operations_rw;
+}
 
-                       if (err == 0) {
-                               if (copy_to_user(uparam, hdr, hdr->ioc_len))
-                                       err = -EFAULT;
-                       }
-                       break;
-               }
-               up_read(&ioctl_list_sem);
-               break; }
-       }
-out:
-       LIBCFS_FREE(hdr, hdr->ioc_len);
-       RETURN(err);
+void lnet_insert_debugfs(struct ctl_table *table)
+{
+       if (!lnet_debugfs_root)
+               lnet_debugfs_root = debugfs_create_dir("lnet", NULL);
+
+       /* Even if we cannot create, just ignore it altogether) */
+       if (IS_ERR_OR_NULL(lnet_debugfs_root))
+               return;
+
+       /* We don't save the dentry returned in next two calls, because
+        * we don't call debugfs_remove() but rather remove_recursive()
+        */
+       for (; table && table->procname; table++)
+               debugfs_create_file(table->procname, table->mode,
+                                   lnet_debugfs_root, table,
+                                   lnet_debugfs_fops_select(table->mode));
 }
+EXPORT_SYMBOL_GPL(lnet_insert_debugfs);
 
-struct cfs_psdev_ops libcfs_psdev_ops = {
-        libcfs_psdev_open,
-        libcfs_psdev_release,
-        NULL,
-        NULL,
-        libcfs_ioctl
-};
+static void lnet_insert_debugfs_links(
+               const struct lnet_debugfs_symlink_def *symlinks)
+{
+       for (; symlinks && symlinks->name; symlinks++)
+               debugfs_create_symlink(symlinks->name, lnet_debugfs_root,
+                                      symlinks->target);
+}
 
-static int init_libcfs_module(void)
+void lnet_remove_debugfs(struct ctl_table *table)
+{
+       for (; table && table->procname; table++) {
+               struct qstr dname = QSTR_INIT(table->procname,
+                                             strlen(table->procname));
+               struct dentry *dentry;
+
+               dentry = d_hash_and_lookup(lnet_debugfs_root, &dname);
+               debugfs_remove(dentry);
+       }
+}
+EXPORT_SYMBOL_GPL(lnet_remove_debugfs);
+
+static int __init libcfs_init(void)
 {
        int rc;
 
@@ -333,12 +614,11 @@ static int init_libcfs_module(void)
                goto cleanup_deregister;
        }
 
-       /* max to 4 threads, should be enough for rehash */
-       rc = min(cfs_cpt_weight(cfs_cpt_table, CFS_CPT_ANY), 4);
-       rc = cfs_wi_sched_create("cfs_rh", cfs_cpt_table, CFS_CPT_ANY,
-                                rc, &cfs_sched_rehash);
-       if (rc != 0) {
-               CERROR("Startup workitem scheduler: error: %d\n", rc);
+       cfs_rehash_wq = alloc_workqueue("cfs_rh", WQ_SYSFS, 4);
+       if (!cfs_rehash_wq) {
+               rc = -ENOMEM;
+               CERROR("libcfs: failed to start rehash workqueue: rc = %d\n",
+                      rc);
                goto cleanup_deregister;
        }
 
@@ -348,17 +628,12 @@ static int init_libcfs_module(void)
                goto cleanup_wi;
        }
 
-
-       rc = insert_proc();
-       if (rc) {
-               CERROR("insert_proc: error %d\n", rc);
-               goto cleanup_crypto;
-       }
+       lnet_insert_debugfs(lnet_table);
+       if (!IS_ERR_OR_NULL(lnet_debugfs_root))
+               lnet_insert_debugfs_links(lnet_debugfs_symlinks);
 
        CDEBUG (D_OTHER, "portals setup OK\n");
        return 0;
-cleanup_crypto:
-       cfs_crypto_unregister();
 cleanup_wi:
        cfs_wi_shutdown();
 cleanup_deregister:
@@ -370,18 +645,20 @@ cleanup_debug:
        return rc;
 }
 
-static void exit_libcfs_module(void)
+static void __exit libcfs_exit(void)
 {
        int rc;
 
-       remove_proc();
+       /* Remove everthing */
+       debugfs_remove_recursive(lnet_debugfs_root);
+       lnet_debugfs_root = NULL;
 
        CDEBUG(D_MALLOC, "before Portals cleanup: kmem %d\n",
               atomic_read(&libcfs_kmemory));
 
-       if (cfs_sched_rehash != NULL) {
-               cfs_wi_sched_destroy(cfs_sched_rehash);
-               cfs_sched_rehash = NULL;
+       if (cfs_rehash_wq) {
+               destroy_workqueue(cfs_rehash_wq);
+               cfs_rehash_wq = NULL;
        }
 
        cfs_crypto_unregister();
@@ -402,9 +679,9 @@ static void exit_libcfs_module(void)
 }
 
 MODULE_AUTHOR("OpenSFS, Inc. <http://www.lustre.org/>");
-MODULE_DESCRIPTION("Libcfs v3.1");
-MODULE_VERSION("1.0.0");
+MODULE_DESCRIPTION("Lustre helper library");
+MODULE_VERSION(LIBCFS_VERSION);
 MODULE_LICENSE("GPL");
 
-module_init(init_libcfs_module);
-module_exit(exit_libcfs_module);
+module_init(libcfs_init);
+module_exit(libcfs_exit);