1 /* proc_lustre.c manages /proc/lustre/obd.
3 * Copyright (c) 2001 Rumi Zahir <rumi.zahir@intel.com>
5 * This code is issued under the GNU General Public License.
6 * See the file COPYING in this distribution
8 * OBD devices materialize in /proc as a directory:
9 * /proc/lustre/obd/<number>
10 * when /dev/obd<number> is opened. When the device is closed, the
11 * directory entry disappears.
13 * For each open OBD device, code in this file also creates a file
14 * named <status>. "cat /proc/lustre/obd/<number>/status" gives
15 * information about the OBD device's configuration.
16 * The class driver manages the "status" entry.
18 * Other logical drivers can create their own entries. For example,
19 * the obdtrace driver creates /proc/lustre/obd/<obdid>/stats entry.
21 * This file defines three functions
22 * proc_lustre_register_obd_device()
23 * proc_lustre_release_obd_device()
24 * proc_lustre_remove_obd_entry()
25 * that dynamically create/delete /proc/lustre/obd entries:
27 * proc_lustre_register_obd_device() registers an obd device,
28 * and, if this is the first OBD device, creates /proc/lustre/obd.
30 * proc_lustre_release_obd_device() removes device information
31 * from /proc/lustre/obd, and if this is the last OBD device
32 * removes /proc/lustre/obd.
34 * proc_lustre_remove_obd_entry() removes a
35 * /proc/lustre/obd/<obdid>/ entry by name. This is the only
36 * function that is exported to other modules.
39 #include <linux/config.h>
40 #include <linux/module.h>
41 #include <linux/version.h>
42 #include <linux/proc_fs.h>
44 #include <linux/obd_support.h>
45 #include <linux/obd_class.h>
49 extern struct proc_dir_entry proc_root;
51 static struct proc_dir_entry *proc_lustre_dir_entry = 0;
52 static struct proc_dir_entry *proc_lustre_obd_dir_entry = 0;
54 static struct proc_dir_entry *
55 proc_lustre_mkdir(const char* dname, struct proc_dir_entry *parent)
57 struct proc_dir_entry *child_dir_entry;
59 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,3,0) /*0x20300 */
60 child_dir_entry = proc_mkdir(dname, parent);
62 child_dir_entry = create_proc_entry(dname,
63 S_IFDIR | S_IRUGO | S_IXUGO,
67 printk ("lustre: failed to create /proc entry %s\n", dname);
69 return child_dir_entry;
72 static int read_lustre_status(char *page, char **start, off_t offset,
73 int count, int *eof, void *data)
75 struct obd_device * obddev = (struct obd_device *) data;
78 p = sprintf(&page[0], "/dev/obd%d: ", obddev->obd_minor);
80 if (obddev->obd_refcnt==0) {
82 p += sprintf(&page[p], "open but unused\n");
84 else { /* obd in use */
85 p += sprintf(&page[p], "refcnt(%d)", obddev->obd_refcnt);
87 if (obddev->obd_flags & OBD_ATTACHED) {
88 p += sprintf(&page[p], ", attached(%s)",
89 obddev->obd_type->typ_name);
92 if (obddev->obd_flags & OBD_SET_UP) {
93 struct dentry *my_dentry;
94 struct vfsmount *root_mnt;
98 if (!(pathpage = (char*) __get_free_page(GFP_KERNEL)))
101 my_dentry = obddev->obd_fsname.dentry;
102 root_mnt = mntget(current->fs->rootmnt);
103 path = d_path(my_dentry,root_mnt,pathpage,PAGE_SIZE);
105 p += sprintf(&page[p], ", setup(%s)", path);
107 free_page((unsigned long) pathpage);
110 /* print connections */
112 struct list_head * lh;
113 struct obd_client * cli=0;
115 lh = &obddev->obd_gen_clients;
116 while ((lh = lh->next) != &obddev->obd_gen_clients) {
117 p += sprintf(&page[p],
118 ((cli==0) ? ", connections(" : ",") );
119 cli = list_entry(lh, struct obd_client, cli_chain);
120 p += sprintf(&page[p], "%d", cli->cli_id);
122 if (cli!=0) { /* there was at least one client */
123 p += sprintf(&page[p], ")");
127 p += sprintf(&page[p], "\n");
130 /* Compute eof and return value */
132 if (offset + count >= p) {
139 struct proc_dir_entry *
140 proc_lustre_register_obd_device(struct obd_device *obd)
143 struct proc_dir_entry *obd_dir;
144 struct proc_dir_entry *obd_status = 0;
146 if (!proc_lustre_dir_entry) {
147 proc_lustre_dir_entry =
148 proc_lustre_mkdir("lustre", &proc_root);
149 if (!proc_lustre_dir_entry)
152 proc_lustre_obd_dir_entry =
153 proc_lustre_mkdir("obd", proc_lustre_dir_entry);
154 if (!proc_lustre_obd_dir_entry)
158 sprintf(obdname, "%d", obd->obd_minor);
160 obd_dir = proc_lustre_mkdir(obdname, proc_lustre_obd_dir_entry);
163 obd_status = create_proc_entry("status", S_IRUSR | S_IFREG, obd_dir);
166 obd_status->read_proc = read_lustre_status;
167 obd_status->data = (void*) obd;
173 void proc_lustre_remove_obd_entry(const char* name, struct obd_device *obd)
175 struct proc_dir_entry *obd_entry = 0;
176 struct proc_dir_entry *obd_dir = obd->obd_proc_entry;
178 remove_proc_entry(name, obd_dir);
180 while (obd_dir->subdir==0) {
181 /* if we removed last entry in this directory,
182 * then remove parent directory unless this
185 if (obd_dir == &proc_root)
189 obd_dir = obd_dir->parent;
191 /* If /proc/lustre/obd/XXX or /proc/lustre/obd or
192 * /proc/lustre are being removed, then reset
196 if (obd_entry == obd->obd_proc_entry)
197 obd->obd_proc_entry=0; /* /proc/lustre/obd/XXX */
199 if (obd_entry == proc_lustre_obd_dir_entry)
200 proc_lustre_obd_dir_entry=0;
202 if (obd_entry == proc_lustre_dir_entry)
203 proc_lustre_dir_entry=0;
205 remove_proc_entry(obd_entry->name, obd_dir);
209 void proc_lustre_release_obd_device(struct obd_device *obd)
211 proc_lustre_remove_obd_entry("status", obd);
215 #else /* CONFIG_PROC_FS */
217 struct proc_dir_entry *proc_lustre_register_obd_device(struct obd_device *obd)
222 void proc_lustre_remove_obd_entry(const char* name, struct obd_device *obd) {}
223 void proc_lustre_release_obd_device(struct obd_device *obd) {}
225 #endif /* CONFIG_PROC_FS */
227 EXPORT_SYMBOL(proc_lustre_remove_obd_entry);