proc: move fs/proc/inode-alloc.txt comment into a source file

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

diff --git a/fs/proc/generic.c b/fs/proc/generic.c
index 9d53b39..8c68bbe 100644 (file)
--- a/fs/proc/generic.c
+++ b/fs/proc/generic.c
@@ -14,7 +14,6 @@
 #include <linux/stat.h>
 #include <linux/module.h>
 #include <linux/mount.h>
-#include <linux/smp_lock.h>
 #include <linux/init.h>
 #include <linux/idr.h>
 #include <linux/namei.h>
@@ -300,47 +299,60 @@ 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
  * 0xffffffff, or zero on failure.
+ *
+ * Current inode allocations in the proc-fs (hex-numbers):
+ *
+ * 00000000            reserved
+ * 00000001-00000fff   static entries  (goners)
+ *      001            root-ino
+ *
+ * 00001000-00001fff   unused
+ * 0001xxxx-7fffxxxx   pid-dir entries for pid 1-7fff
+ * 80000000-efffffff   unused
+ * f0000000-ffffffff   dynamic entries
+ *
+ * Goal:
+ *     Once we split the thing into several virtual filesystems,
+ *     we will get rid of magical ranges (and this comment, BTW).
  */
 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);
 }
 
@@ -366,7 +378,7 @@ static int proc_delete_dentry(struct dentry * dentry)
        return 1;
 }
 
-static struct dentry_operations proc_dentry_operations =
+static const struct dentry_operations proc_dentry_operations =
 {
        .d_delete       = proc_delete_dentry,
 };
@@ -381,7 +393,6 @@ struct dentry *proc_lookup_de(struct proc_dir_entry *de, struct inode *dir,
        struct inode *inode = NULL;
        int error = -ENOENT;
 
-       lock_kernel();
        spin_lock(&proc_subdir_lock);
        for (de = de->subdir; de ; de = de->next) {
                if (de->namelen != dentry->d_name.len)
@@ -399,7 +410,6 @@ struct dentry *proc_lookup_de(struct proc_dir_entry *de, struct inode *dir,
        }
        spin_unlock(&proc_subdir_lock);
 out_unlock:
-       unlock_kernel();
 
        if (inode) {
                dentry->d_op = &proc_dentry_operations;
@@ -434,8 +444,6 @@ int proc_readdir_de(struct proc_dir_entry *de, struct file *filp, void *dirent,
        struct inode *inode = filp->f_path.dentry->d_inode;
        int ret = 0;
 
-       lock_kernel();
-
        ino = inode->i_ino;
        i = filp->f_pos;
        switch (i) {
@@ -489,7 +497,7 @@ int proc_readdir_de(struct proc_dir_entry *de, struct file *filp, void *dirent,
                        spin_unlock(&proc_subdir_lock);
        }
        ret = 1;
-out:   unlock_kernel();
+out:
        return ret;     
 }
 
@@ -506,6 +514,7 @@ int proc_readdir(struct file *filp, void *dirent, filldir_t filldir)
  * the /proc directory.
  */
 static const struct file_operations proc_dir_operations = {
+       .llseek                 = generic_file_llseek,
        .read                   = generic_read_dir,
        .readdir                = proc_readdir,
 };
@@ -549,9 +558,8 @@ 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);
-                       dump_stack();
+                       WARN(1, KERN_WARNING "proc_dir_entry '%s/%s' already registered\n",
+                               dir->name, dp->name);
                        break;
                }
 
@@ -597,6 +605,7 @@ 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;
 }
@@ -641,6 +650,23 @@ 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)
 {
@@ -772,15 +798,25 @@ 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);
 }