Fedora kernel-2.6.17-1.2142_FC4 patched with stable patch-2.6.17.4-vs2.0.2-rc26.diff
[linux-2.6.git] / fs / autofs4 / inode.c
index 4bb14cc..fde78b1 100644 (file)
@@ -3,6 +3,7 @@
  * linux/fs/autofs/inode.c
  *
  *  Copyright 1997-1998 Transmeta Corporation -- All Rights Reserved
+ *  Copyright 2005-2006 Ian Kent <raven@themaw.net>
  *
  * This file is part of the Linux kernel and is made available under
  * the terms of the GNU General Public License, version 2, or at your
 #include <linux/kernel.h>
 #include <linux/slab.h>
 #include <linux/file.h>
+#include <linux/seq_file.h>
 #include <linux/pagemap.h>
 #include <linux/parser.h>
 #include <linux/bitops.h>
+#include <linux/smp_lock.h>
 #include "autofs_i.h"
 #include <linux/module.h>
 
 static void ino_lnkfree(struct autofs_info *ino)
 {
-       if (ino->u.symlink) {
-               kfree(ino->u.symlink);
-               ino->u.symlink = NULL;
-       }
+       kfree(ino->u.symlink);
+       ino->u.symlink = NULL;
 }
 
 struct autofs_info *autofs4_init_ino(struct autofs_info *ino,
@@ -47,6 +48,7 @@ struct autofs_info *autofs4_init_ino(struct autofs_info *ino,
        ino->size = 0;
 
        ino->last_used = jiffies;
+       atomic_set(&ino->count, 0);
 
        ino->sbi = sbi;
 
@@ -65,10 +67,19 @@ struct autofs_info *autofs4_init_ino(struct autofs_info *ino,
 
 void autofs4_free_ino(struct autofs_info *ino)
 {
+       struct autofs_info *p_ino;
+
        if (ino->dentry) {
                ino->dentry->d_fsdata = NULL;
-               if (ino->dentry->d_inode)
+               if (ino->dentry->d_inode) {
+                       struct dentry *parent = ino->dentry->d_parent;
+                       if (atomic_dec_and_test(&ino->count)) {
+                               p_ino = autofs4_dentry_ino(parent);
+                               if (p_ino && parent != ino->dentry)
+                                       atomic_dec(&p_ino->count);
+                       }
                        dput(ino->dentry);
+               }
                ino->dentry = NULL;
        }
        if (ino->free)
@@ -76,6 +87,66 @@ void autofs4_free_ino(struct autofs_info *ino)
        kfree(ino);
 }
 
+/*
+ * Deal with the infamous "Busy inodes after umount ..." message.
+ *
+ * Clean up the dentry tree. This happens with autofs if the user
+ * space program goes away due to a SIGKILL, SIGSEGV etc.
+ */
+static void autofs4_force_release(struct autofs_sb_info *sbi)
+{
+       struct dentry *this_parent = sbi->root;
+       struct list_head *next;
+
+       spin_lock(&dcache_lock);
+repeat:
+       next = this_parent->d_subdirs.next;
+resume:
+       while (next != &this_parent->d_subdirs) {
+               struct dentry *dentry = list_entry(next, struct dentry, d_u.d_child);
+
+               /* Negative dentry - don`t care */
+               if (!simple_positive(dentry)) {
+                       next = next->next;
+                       continue;
+               }
+
+               if (!list_empty(&dentry->d_subdirs)) {
+                       this_parent = dentry;
+                       goto repeat;
+               }
+
+               next = next->next;
+               spin_unlock(&dcache_lock);
+
+               DPRINTK("dentry %p %.*s",
+                       dentry, (int)dentry->d_name.len, dentry->d_name.name);
+
+               dput(dentry);
+               spin_lock(&dcache_lock);
+       }
+
+       if (this_parent != sbi->root) {
+               struct dentry *dentry = this_parent;
+
+               next = this_parent->d_u.d_child.next;
+               this_parent = this_parent->d_parent;
+               spin_unlock(&dcache_lock);
+               DPRINTK("parent dentry %p %.*s",
+                       dentry, (int)dentry->d_name.len, dentry->d_name.name);
+               dput(dentry);
+               spin_lock(&dcache_lock);
+               goto resume;
+       }
+       spin_unlock(&dcache_lock);
+
+       dput(sbi->root);
+       sbi->root = NULL;
+       shrink_dcache_sb(sbi->sb);
+
+       return;
+}
+
 static void autofs4_put_super(struct super_block *sb)
 {
        struct autofs_sb_info *sbi = autofs4_sbi(sb);
@@ -85,17 +156,45 @@ static void autofs4_put_super(struct super_block *sb)
        if ( !sbi->catatonic )
                autofs4_catatonic_mode(sbi); /* Free wait queues, close pipe */
 
+       /* Clean up and release dangling references */
+       autofs4_force_release(sbi);
+
        kfree(sbi);
 
        DPRINTK("shutting down");
 }
 
+static int autofs4_show_options(struct seq_file *m, struct vfsmount *mnt)
+{
+       struct autofs_sb_info *sbi = autofs4_sbi(mnt->mnt_sb);
+
+       if (!sbi)
+               return 0;
+
+       seq_printf(m, ",fd=%d", sbi->pipefd);
+       seq_printf(m, ",pgrp=%d", sbi->oz_pgrp);
+       seq_printf(m, ",timeout=%lu", sbi->exp_timeout/HZ);
+       seq_printf(m, ",minproto=%d", sbi->min_proto);
+       seq_printf(m, ",maxproto=%d", sbi->max_proto);
+
+       if (sbi->type & AUTOFS_TYPE_OFFSET)
+               seq_printf(m, ",offset");
+       else if (sbi->type & AUTOFS_TYPE_DIRECT)
+               seq_printf(m, ",direct");
+       else
+               seq_printf(m, ",indirect");
+
+       return 0;
+}
+
 static struct super_operations autofs4_sops = {
        .put_super      = autofs4_put_super,
        .statfs         = simple_statfs,
+       .show_options   = autofs4_show_options,
 };
 
-enum {Opt_err, Opt_fd, Opt_uid, Opt_gid, Opt_pgrp, Opt_minproto, Opt_maxproto};
+enum {Opt_err, Opt_fd, Opt_uid, Opt_gid, Opt_pgrp, Opt_minproto, Opt_maxproto,
+       Opt_indirect, Opt_direct, Opt_offset};
 
 static match_table_t tokens = {
        {Opt_fd, "fd=%u"},
@@ -104,11 +203,15 @@ static match_table_t tokens = {
        {Opt_pgrp, "pgrp=%u"},
        {Opt_minproto, "minproto=%u"},
        {Opt_maxproto, "maxproto=%u"},
+       {Opt_indirect, "indirect"},
+       {Opt_direct, "direct"},
+       {Opt_offset, "offset"},
        {Opt_err, NULL}
 };
 
 static int parse_options(char *options, int *pipefd, uid_t *uid, gid_t *gid,
-                        pid_t *pgrp, int *minproto, int *maxproto)
+                        pid_t *pgrp, unsigned int *type,
+                        int *minproto, int *maxproto)
 {
        char *p;
        substring_t args[MAX_OPT_ARGS];
@@ -162,6 +265,15 @@ static int parse_options(char *options, int *pipefd, uid_t *uid, gid_t *gid,
                                return 1;
                        *maxproto = option;
                        break;
+               case Opt_indirect:
+                       *type = AUTOFS_TYPE_INDIRECT;
+                       break;
+               case Opt_direct:
+                       *type = AUTOFS_TYPE_DIRECT;
+                       break;
+               case Opt_offset:
+                       *type = AUTOFS_TYPE_DIRECT | AUTOFS_TYPE_OFFSET;
+                       break;
                default:
                        return 1;
                }
@@ -180,6 +292,10 @@ static struct autofs_info *autofs4_mkroot(struct autofs_sb_info *sbi)
        return ino;
 }
 
+static struct dentry_operations autofs4_sb_dentry_operations = {
+       .d_release      = autofs4_dentry_release,
+};
+
 int autofs4_fill_super(struct super_block *s, void *data, int silent)
 {
        struct inode * root_inode;
@@ -188,7 +304,6 @@ int autofs4_fill_super(struct super_block *s, void *data, int silent)
        int pipefd;
        struct autofs_sb_info *sbi;
        struct autofs_info *ino;
-       int minproto, maxproto;
 
        sbi = (struct autofs_sb_info *) kmalloc(sizeof(*sbi), GFP_KERNEL);
        if ( !sbi )
@@ -199,13 +314,18 @@ int autofs4_fill_super(struct super_block *s, void *data, int silent)
 
        s->s_fs_info = sbi;
        sbi->magic = AUTOFS_SBI_MAGIC;
+       sbi->root = NULL;
+       sbi->pipefd = -1;
        sbi->catatonic = 0;
        sbi->exp_timeout = 0;
        sbi->oz_pgrp = process_group(current);
        sbi->sb = s;
        sbi->version = 0;
        sbi->sub_version = 0;
-       init_MUTEX(&sbi->wq_sem);
+       sbi->type = 0;
+       sbi->min_proto = 0;
+       sbi->max_proto = 0;
+       mutex_init(&sbi->wq_mutex);
        spin_lock_init(&sbi->fs_lock);
        sbi->queues = NULL;
        s->s_blocksize = 1024;
@@ -221,38 +341,46 @@ int autofs4_fill_super(struct super_block *s, void *data, int silent)
        if (!ino)
                goto fail_free;
        root_inode = autofs4_get_inode(s, ino);
-       kfree(ino);
        if (!root_inode)
-               goto fail_free;
+               goto fail_ino;
 
-       root_inode->i_op = &autofs4_root_inode_operations;
-       root_inode->i_fop = &autofs4_root_operations;
        root = d_alloc_root(root_inode);
-       pipe = NULL;
-
        if (!root)
                goto fail_iput;
+       pipe = NULL;
+
+       root->d_op = &autofs4_sb_dentry_operations;
+       root->d_fsdata = ino;
 
        /* Can this call block? */
        if (parse_options(data, &pipefd,
                          &root_inode->i_uid, &root_inode->i_gid,
-                         &sbi->oz_pgrp,
-                         &minproto, &maxproto)) {
+                         &sbi->oz_pgrp, &sbi->type,
+                         &sbi->min_proto, &sbi->max_proto)) {
                printk("autofs: called with bogus options\n");
                goto fail_dput;
        }
 
+       root_inode->i_fop = &autofs4_root_operations;
+       root_inode->i_op = sbi->type & AUTOFS_TYPE_DIRECT ?
+                       &autofs4_direct_root_inode_operations :
+                       &autofs4_indirect_root_inode_operations;
+
        /* Couldn't this be tested earlier? */
-       if (maxproto < AUTOFS_MIN_PROTO_VERSION ||
-           minproto > AUTOFS_MAX_PROTO_VERSION) {
+       if (sbi->max_proto < AUTOFS_MIN_PROTO_VERSION ||
+           sbi->min_proto > AUTOFS_MAX_PROTO_VERSION) {
                printk("autofs: kernel does not match daemon version "
                       "daemon (%d, %d) kernel (%d, %d)\n",
-                       minproto, maxproto,
+                       sbi->min_proto, sbi->max_proto,
                        AUTOFS_MIN_PROTO_VERSION, AUTOFS_MAX_PROTO_VERSION);
                goto fail_dput;
        }
 
-       sbi->version = maxproto > AUTOFS_MAX_PROTO_VERSION ? AUTOFS_MAX_PROTO_VERSION : maxproto;
+       /* Establish highest kernel protocol version */
+       if (sbi->max_proto > AUTOFS_MAX_PROTO_VERSION)
+               sbi->version = AUTOFS_MAX_PROTO_VERSION;
+       else
+               sbi->version = sbi->max_proto;
        sbi->sub_version = AUTOFS_PROTO_SUBVERSION;
 
        DPRINTK("pipe fd = %d, pgrp = %u", pipefd, sbi->oz_pgrp);
@@ -265,6 +393,14 @@ int autofs4_fill_super(struct super_block *s, void *data, int silent)
        if ( !pipe->f_op || !pipe->f_op->write )
                goto fail_fput;
        sbi->pipe = pipe;
+       sbi->pipefd = pipefd;
+
+       /*
+        * Take a reference to the root dentry so we get a chance to
+        * clean up the dentry tree on umount.
+        * See autofs4_force_release.
+        */
+       sbi->root = dget(root);
 
        /*
         * Success! Install the root dentry now to indicate completion.
@@ -285,6 +421,8 @@ fail_dput:
 fail_iput:
        printk("autofs: get root dentry failed\n");
        iput(root_inode);
+fail_ino:
+       kfree(ino);
 fail_free:
        kfree(sbi);
 fail_unlock: