proc: more debugging for "already registered" case

[safe/jmp/linux-2.6] / fs / proc / generic.c

diff --git a/fs/proc/generic.c b/fs/proc/generic.c
index 8b406e2..7821589 100644 (file)
--- a/fs/proc/generic.c
+++ b/fs/proc/generic.c
@@ -69,12 +69,7 @@ proc_file_read(struct file *file, char __user *buf, size_t nbytes,
                count = min_t(size_t, PROC_BLOCK_SIZE, nbytes);
 
                start = NULL;
-               if (dp->get_info) {
-                       /* Handle old net routines */
-                       n = dp->get_info(page, &start, *ppos, count);
-                       if (n < count)
-                               eof = 1;
-               } else if (dp->read_proc) {
+               if (dp->read_proc) {
                        /*
                         * How to be a proc read function
                         * ------------------------------
@@ -305,10 +300,10 @@ out:
        return rtn;
 }
 
-static DEFINE_IDR(proc_inum_idr);
+static DEFINE_IDA(proc_inum_ida);
 static DEFINE_SPINLOCK(proc_inum_lock); /* protects the above */
 
-#define PROC_DYNAMIC_FIRST 0xF0000000UL
+#define PROC_DYNAMIC_FIRST 0xF0000000U
 
 /*
  * Return an inode number between PROC_DYNAMIC_FIRST and
@@ -316,36 +311,34 @@ static DEFINE_SPINLOCK(proc_inum_lock); /* protects the above */
  */
 static unsigned int get_inode_number(void)
 {
-       int i, inum = 0;
+       unsigned int i;
        int error;
 
 retry:
-       if (idr_pre_get(&proc_inum_idr, GFP_KERNEL) == 0)
+       if (ida_pre_get(&proc_inum_ida, GFP_KERNEL) == 0)
                return 0;
 
        spin_lock(&proc_inum_lock);
-       error = idr_get_new(&proc_inum_idr, NULL, &i);
+       error = ida_get_new(&proc_inum_ida, &i);
        spin_unlock(&proc_inum_lock);
        if (error == -EAGAIN)
                goto retry;
        else if (error)
                return 0;
 
-       inum = (i & MAX_ID_MASK) + PROC_DYNAMIC_FIRST;
-
-       /* inum will never be more than 0xf0ffffff, so no check
-        * for overflow.
-        */
-
-       return inum;
+       if (i > UINT_MAX - PROC_DYNAMIC_FIRST) {
+               spin_lock(&proc_inum_lock);
+               ida_remove(&proc_inum_ida, i);
+               spin_unlock(&proc_inum_lock);
+               return 0;
+       }
+       return PROC_DYNAMIC_FIRST + i;
 }
 
 static void release_inode_number(unsigned int inum)
 {
-       int id = (inum - PROC_DYNAMIC_FIRST) | ~MAX_ID_MASK;
-
        spin_lock(&proc_inum_lock);
-       idr_remove(&proc_inum_idr, id);
+       ida_remove(&proc_inum_ida, inum - PROC_DYNAMIC_FIRST);
        spin_unlock(&proc_inum_lock);
 }
 
@@ -554,8 +547,8 @@ static int proc_register(struct proc_dir_entry * dir, struct proc_dir_entry * dp
 
        for (tmp = dir->subdir; tmp; tmp = tmp->next)
                if (strcmp(tmp->name, dp->name) == 0) {
-                       printk(KERN_WARNING "proc_dir_entry '%s' already "
-                                       "registered\n", dp->name);
+                       printk(KERN_WARNING "proc_dir_entry '%s/%s' already registered\n",
+                               dir->name, dp->name);
                        dump_stack();
                        break;
                }
@@ -602,6 +595,7 @@ static struct proc_dir_entry *__proc_create(struct proc_dir_entry **parent,
        ent->pde_users = 0;
        spin_lock_init(&ent->pde_unload_lock);
        ent->pde_unload_completion = NULL;
+       INIT_LIST_HEAD(&ent->pde_openers);
  out:
        return ent;
 }
@@ -646,6 +640,23 @@ struct proc_dir_entry *proc_mkdir_mode(const char *name, mode_t mode,
        return ent;
 }
 
+struct proc_dir_entry *proc_net_mkdir(struct net *net, const char *name,
+               struct proc_dir_entry *parent)
+{
+       struct proc_dir_entry *ent;
+
+       ent = __proc_create(&parent, name, S_IFDIR | S_IRUGO | S_IXUGO, 2);
+       if (ent) {
+               ent->data = net;
+               if (proc_register(parent, ent) < 0) {
+                       kfree(ent);
+                       ent = NULL;
+               }
+       }
+       return ent;
+}
+EXPORT_SYMBOL_GPL(proc_net_mkdir);
+
 struct proc_dir_entry *proc_mkdir(const char *name,
                struct proc_dir_entry *parent)
 {
@@ -680,9 +691,10 @@ struct proc_dir_entry *create_proc_entry(const char *name, mode_t mode,
        return ent;
 }
 
-struct proc_dir_entry *proc_create(const char *name, mode_t mode,
-                                  struct proc_dir_entry *parent,
-                                  const struct file_operations *proc_fops)
+struct proc_dir_entry *proc_create_data(const char *name, mode_t mode,
+                                       struct proc_dir_entry *parent,
+                                       const struct file_operations *proc_fops,
+                                       void *data)
 {
        struct proc_dir_entry *pde;
        nlink_t nlink;
@@ -703,6 +715,7 @@ struct proc_dir_entry *proc_create(const char *name, mode_t mode,
        if (!pde)
                goto out;
        pde->proc_fops = proc_fops;
+       pde->data = data;
        if (proc_register(parent, pde) < 0)
                goto out_free;
        return pde;
@@ -775,15 +788,25 @@ void remove_proc_entry(const char *name, struct proc_dir_entry *parent)
        spin_unlock(&de->pde_unload_lock);
 
 continue_removing:
+       spin_lock(&de->pde_unload_lock);
+       while (!list_empty(&de->pde_openers)) {
+               struct pde_opener *pdeo;
+
+               pdeo = list_first_entry(&de->pde_openers, struct pde_opener, lh);
+               list_del(&pdeo->lh);
+               spin_unlock(&de->pde_unload_lock);
+               pdeo->release(pdeo->inode, pdeo->file);
+               kfree(pdeo);
+               spin_lock(&de->pde_unload_lock);
+       }
+       spin_unlock(&de->pde_unload_lock);
+
        if (S_ISDIR(de->mode))
                parent->nlink--;
        de->nlink = 0;
-       if (de->subdir) {
-               printk(KERN_WARNING "%s: removing non-empty directory "
+       WARN(de->subdir, KERN_WARNING "%s: removing non-empty directory "
                        "'%s/%s', leaking at least '%s'\n", __func__,
                        de->parent->name, de->name, de->subdir->name);
-               WARN_ON(1);
-       }
        if (atomic_dec_and_test(&de->count))
                free_proc_entry(de);
 }