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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /fs/autofs4
downloadlwn-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.gz
lwn-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.zip
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'fs/autofs4')
-rw-r--r--fs/autofs4/Makefile7
-rw-r--r--fs/autofs4/autofs_i.h193
-rw-r--r--fs/autofs4/expire.c358
-rw-r--r--fs/autofs4/init.c42
-rw-r--r--fs/autofs4/inode.c324
-rw-r--r--fs/autofs4/root.c808
-rw-r--r--fs/autofs4/symlink.c25
-rw-r--r--fs/autofs4/waitq.c303
8 files changed, 2060 insertions, 0 deletions
diff --git a/fs/autofs4/Makefile b/fs/autofs4/Makefile
new file mode 100644
index 000000000000..f2c3b79e94d2
--- /dev/null
+++ b/fs/autofs4/Makefile
@@ -0,0 +1,7 @@
+#
+# Makefile for the linux autofs-filesystem routines.
+#
+
+obj-$(CONFIG_AUTOFS4_FS) += autofs4.o
+
+autofs4-objs := init.o inode.o root.o symlink.o waitq.o expire.o
diff --git a/fs/autofs4/autofs_i.h b/fs/autofs4/autofs_i.h
new file mode 100644
index 000000000000..f5a52c871726
--- /dev/null
+++ b/fs/autofs4/autofs_i.h
@@ -0,0 +1,193 @@
+/* -*- c -*- ------------------------------------------------------------- *
+ *
+ * linux/fs/autofs/autofs_i.h
+ *
+ * Copyright 1997-1998 Transmeta Corporation - All Rights Reserved
+ *
+ * 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
+ * option, any later version, incorporated herein by reference.
+ *
+ * ----------------------------------------------------------------------- */
+
+/* Internal header file for autofs */
+
+#include <linux/auto_fs4.h>
+#include <linux/list.h>
+
+/* This is the range of ioctl() numbers we claim as ours */
+#define AUTOFS_IOC_FIRST AUTOFS_IOC_READY
+#define AUTOFS_IOC_COUNT 32
+
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/time.h>
+#include <linux/string.h>
+#include <linux/wait.h>
+#include <linux/sched.h>
+#include <linux/mount.h>
+#include <linux/namei.h>
+#include <asm/current.h>
+#include <asm/uaccess.h>
+
+/* #define DEBUG */
+
+#ifdef DEBUG
+#define DPRINTK(fmt,args...) do { printk(KERN_DEBUG "pid %d: %s: " fmt "\n" , current->pid , __FUNCTION__ , ##args); } while(0)
+#else
+#define DPRINTK(fmt,args...) do {} while(0)
+#endif
+
+#define AUTOFS_SUPER_MAGIC 0x0187
+
+/*
+ * If the daemon returns a negative response (AUTOFS_IOC_FAIL) then the
+ * kernel will keep the negative response cached for up to the time given
+ * here, although the time can be shorter if the kernel throws the dcache
+ * entry away. This probably should be settable from user space.
+ */
+#define AUTOFS_NEGATIVE_TIMEOUT (60*HZ) /* 1 minute */
+
+/* Unified info structure. This is pointed to by both the dentry and
+ inode structures. Each file in the filesystem has an instance of this
+ structure. It holds a reference to the dentry, so dentries are never
+ flushed while the file exists. All name lookups are dealt with at the
+ dentry level, although the filesystem can interfere in the validation
+ process. Readdir is implemented by traversing the dentry lists. */
+struct autofs_info {
+ struct dentry *dentry;
+ struct inode *inode;
+
+ int flags;
+
+ struct autofs_sb_info *sbi;
+ unsigned long last_used;
+
+ mode_t mode;
+ size_t size;
+
+ void (*free)(struct autofs_info *);
+ union {
+ const char *symlink;
+ } u;
+};
+
+#define AUTOFS_INF_EXPIRING (1<<0) /* dentry is in the process of expiring */
+
+struct autofs_wait_queue {
+ wait_queue_head_t queue;
+ struct autofs_wait_queue *next;
+ autofs_wqt_t wait_queue_token;
+ /* We use the following to see what we are waiting for */
+ int hash;
+ int len;
+ char *name;
+ /* This is for status reporting upon return */
+ int status;
+ atomic_t wait_ctr;
+};
+
+#define AUTOFS_SBI_MAGIC 0x6d4a556d
+
+struct autofs_sb_info {
+ u32 magic;
+ struct file *pipe;
+ pid_t oz_pgrp;
+ int catatonic;
+ int version;
+ int sub_version;
+ unsigned long exp_timeout;
+ int reghost_enabled;
+ int needs_reghost;
+ struct super_block *sb;
+ struct semaphore wq_sem;
+ struct autofs_wait_queue *queues; /* Wait queue pointer */
+};
+
+static inline struct autofs_sb_info *autofs4_sbi(struct super_block *sb)
+{
+ return (struct autofs_sb_info *)(sb->s_fs_info);
+}
+
+static inline struct autofs_info *autofs4_dentry_ino(struct dentry *dentry)
+{
+ return (struct autofs_info *)(dentry->d_fsdata);
+}
+
+/* autofs4_oz_mode(): do we see the man behind the curtain? (The
+ processes which do manipulations for us in user space sees the raw
+ filesystem without "magic".) */
+
+static inline int autofs4_oz_mode(struct autofs_sb_info *sbi) {
+ return sbi->catatonic || process_group(current) == sbi->oz_pgrp;
+}
+
+/* Does a dentry have some pending activity? */
+static inline int autofs4_ispending(struct dentry *dentry)
+{
+ struct autofs_info *inf = autofs4_dentry_ino(dentry);
+
+ return (dentry->d_flags & DCACHE_AUTOFS_PENDING) ||
+ (inf != NULL && inf->flags & AUTOFS_INF_EXPIRING);
+}
+
+static inline void autofs4_copy_atime(struct file *src, struct file *dst)
+{
+ dst->f_dentry->d_inode->i_atime = src->f_dentry->d_inode->i_atime;
+ return;
+}
+
+struct inode *autofs4_get_inode(struct super_block *, struct autofs_info *);
+void autofs4_free_ino(struct autofs_info *);
+
+/* Expiration */
+int is_autofs4_dentry(struct dentry *);
+int autofs4_expire_run(struct super_block *, struct vfsmount *,
+ struct autofs_sb_info *,
+ struct autofs_packet_expire __user *);
+int autofs4_expire_multi(struct super_block *, struct vfsmount *,
+ struct autofs_sb_info *, int __user *);
+
+/* Operations structures */
+
+extern struct inode_operations autofs4_symlink_inode_operations;
+extern struct inode_operations autofs4_dir_inode_operations;
+extern struct inode_operations autofs4_root_inode_operations;
+extern struct file_operations autofs4_dir_operations;
+extern struct file_operations autofs4_root_operations;
+
+/* Initializing function */
+
+int autofs4_fill_super(struct super_block *, void *, int);
+struct autofs_info *autofs4_init_ino(struct autofs_info *, struct autofs_sb_info *sbi, mode_t mode);
+
+/* Queue management functions */
+
+enum autofs_notify
+{
+ NFY_NONE,
+ NFY_MOUNT,
+ NFY_EXPIRE
+};
+
+int autofs4_wait(struct autofs_sb_info *,struct dentry *, enum autofs_notify);
+int autofs4_wait_release(struct autofs_sb_info *,autofs_wqt_t,int);
+void autofs4_catatonic_mode(struct autofs_sb_info *);
+
+static inline int simple_positive(struct dentry *dentry)
+{
+ return dentry->d_inode && !d_unhashed(dentry);
+}
+
+static inline int simple_empty_nolock(struct dentry *dentry)
+{
+ struct dentry *child;
+ int ret = 0;
+
+ list_for_each_entry(child, &dentry->d_subdirs, d_child)
+ if (simple_positive(child))
+ goto out;
+ ret = 1;
+out:
+ return ret;
+}
diff --git a/fs/autofs4/expire.c b/fs/autofs4/expire.c
new file mode 100644
index 000000000000..31540a6404d9
--- /dev/null
+++ b/fs/autofs4/expire.c
@@ -0,0 +1,358 @@
+/* -*- c -*- --------------------------------------------------------------- *
+ *
+ * linux/fs/autofs/expire.c
+ *
+ * Copyright 1997-1998 Transmeta Corporation -- All Rights Reserved
+ * Copyright 1999-2000 Jeremy Fitzhardinge <jeremy@goop.org>
+ * Copyright 2001-2003 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
+ * option, any later version, incorporated herein by reference.
+ *
+ * ------------------------------------------------------------------------- */
+
+#include "autofs_i.h"
+
+static unsigned long now;
+
+/* Check if a dentry can be expired return 1 if it can else return 0 */
+static inline int autofs4_can_expire(struct dentry *dentry,
+ unsigned long timeout, int do_now)
+{
+ struct autofs_info *ino = autofs4_dentry_ino(dentry);
+
+ /* dentry in the process of being deleted */
+ if (ino == NULL)
+ return 0;
+
+ /* No point expiring a pending mount */
+ if (dentry->d_flags & DCACHE_AUTOFS_PENDING)
+ return 0;
+
+ if (!do_now) {
+ /* Too young to die */
+ if (time_after(ino->last_used + timeout, now))
+ return 0;
+
+ /* update last_used here :-
+ - obviously makes sense if it is in use now
+ - less obviously, prevents rapid-fire expire
+ attempts if expire fails the first time */
+ ino->last_used = now;
+ }
+
+ return 1;
+}
+
+/* Check a mount point for busyness return 1 if not busy, otherwise */
+static int autofs4_check_mount(struct vfsmount *mnt, struct dentry *dentry)
+{
+ int status = 0;
+
+ DPRINTK("dentry %p %.*s",
+ dentry, (int)dentry->d_name.len, dentry->d_name.name);
+
+ mntget(mnt);
+ dget(dentry);
+
+ if (!follow_down(&mnt, &dentry))
+ goto done;
+
+ while (d_mountpoint(dentry) && follow_down(&mnt, &dentry))
+ ;
+
+ /* This is an autofs submount, we can't expire it */
+ if (is_autofs4_dentry(dentry))
+ goto done;
+
+ /* The big question */
+ if (may_umount_tree(mnt) == 0)
+ status = 1;
+done:
+ DPRINTK("returning = %d", status);
+ mntput(mnt);
+ dput(dentry);
+ return status;
+}
+
+/* Check a directory tree of mount points for busyness
+ * The tree is not busy iff no mountpoints are busy
+ * Return 1 if the tree is busy or 0 otherwise
+ */
+static int autofs4_check_tree(struct vfsmount *mnt,
+ struct dentry *top,
+ unsigned long timeout,
+ int do_now)
+{
+ struct dentry *this_parent = top;
+ struct list_head *next;
+
+ DPRINTK("parent %p %.*s",
+ top, (int)top->d_name.len, top->d_name.name);
+
+ /* Negative dentry - give up */
+ if (!simple_positive(top))
+ return 0;
+
+ /* Timeout of a tree mount is determined by its top dentry */
+ if (!autofs4_can_expire(top, timeout, do_now))
+ return 0;
+
+ 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_child);
+
+ /* Negative dentry - give up */
+ if (!simple_positive(dentry)) {
+ next = next->next;
+ continue;
+ }
+
+ DPRINTK("dentry %p %.*s",
+ dentry, (int)dentry->d_name.len, dentry->d_name.name);
+
+ if (!simple_empty_nolock(dentry)) {
+ this_parent = dentry;
+ goto repeat;
+ }
+
+ dentry = dget(dentry);
+ spin_unlock(&dcache_lock);
+
+ if (d_mountpoint(dentry)) {
+ /* First busy => tree busy */
+ if (!autofs4_check_mount(mnt, dentry)) {
+ dput(dentry);
+ return 0;
+ }
+ }
+
+ dput(dentry);
+ spin_lock(&dcache_lock);
+ next = next->next;
+ }
+
+ if (this_parent != top) {
+ next = this_parent->d_child.next;
+ this_parent = this_parent->d_parent;
+ goto resume;
+ }
+ spin_unlock(&dcache_lock);
+
+ return 1;
+}
+
+static struct dentry *autofs4_check_leaves(struct vfsmount *mnt,
+ struct dentry *parent,
+ unsigned long timeout,
+ int do_now)
+{
+ struct dentry *this_parent = parent;
+ struct list_head *next;
+
+ DPRINTK("parent %p %.*s",
+ parent, (int)parent->d_name.len, parent->d_name.name);
+
+ 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_child);
+
+ /* Negative dentry - give up */
+ if (!simple_positive(dentry)) {
+ next = next->next;
+ continue;
+ }
+
+ DPRINTK("dentry %p %.*s",
+ dentry, (int)dentry->d_name.len, dentry->d_name.name);
+
+ if (!list_empty(&dentry->d_subdirs)) {
+ this_parent = dentry;
+ goto repeat;
+ }
+
+ dentry = dget(dentry);
+ spin_unlock(&dcache_lock);
+
+ if (d_mountpoint(dentry)) {
+ /* Can we expire this guy */
+ if (!autofs4_can_expire(dentry, timeout, do_now))
+ goto cont;
+
+ /* Can we umount this guy */
+ if (autofs4_check_mount(mnt, dentry))
+ return dentry;
+
+ }
+cont:
+ dput(dentry);
+ spin_lock(&dcache_lock);
+ next = next->next;
+ }
+
+ if (this_parent != parent) {
+ next = this_parent->d_child.next;
+ this_parent = this_parent->d_parent;
+ goto resume;
+ }
+ spin_unlock(&dcache_lock);
+
+ return NULL;
+}
+
+/*
+ * Find an eligible tree to time-out
+ * A tree is eligible if :-
+ * - it is unused by any user process
+ * - it has been unused for exp_timeout time
+ */
+static struct dentry *autofs4_expire(struct super_block *sb,
+ struct vfsmount *mnt,
+ struct autofs_sb_info *sbi,
+ int how)
+{
+ unsigned long timeout;
+ struct dentry *root = sb->s_root;
+ struct dentry *expired = NULL;
+ struct list_head *next;
+ int do_now = how & AUTOFS_EXP_IMMEDIATE;
+ int exp_leaves = how & AUTOFS_EXP_LEAVES;
+
+ if ( !sbi->exp_timeout || !root )
+ return NULL;
+
+ now = jiffies;
+ timeout = sbi->exp_timeout;
+
+ spin_lock(&dcache_lock);
+ next = root->d_subdirs.next;
+
+ /* On exit from the loop expire is set to a dgot dentry
+ * to expire or it's NULL */
+ while ( next != &root->d_subdirs ) {
+ struct dentry *dentry = list_entry(next, struct dentry, d_child);
+
+ /* Negative dentry - give up */
+ if ( !simple_positive(dentry) ) {
+ next = next->next;
+ continue;
+ }
+
+ dentry = dget(dentry);
+ spin_unlock(&dcache_lock);
+
+ /* Case 1: indirect mount or top level direct mount */
+ if (d_mountpoint(dentry)) {
+ DPRINTK("checking mountpoint %p %.*s",
+ dentry, (int)dentry->d_name.len, dentry->d_name.name);
+
+ /* Can we expire this guy */
+ if (!autofs4_can_expire(dentry, timeout, do_now))
+ goto next;
+
+ /* Can we umount this guy */
+ if (autofs4_check_mount(mnt, dentry)) {
+ expired = dentry;
+ break;
+ }
+ goto next;
+ }
+
+ if ( simple_empty(dentry) )
+ goto next;
+
+ /* Case 2: tree mount, expire iff entire tree is not busy */
+ if (!exp_leaves) {
+ if (autofs4_check_tree(mnt, dentry, timeout, do_now)) {
+ expired = dentry;
+ break;
+ }
+ /* Case 3: direct mount, expire individual leaves */
+ } else {
+ expired = autofs4_check_leaves(mnt, dentry, timeout, do_now);
+ if (expired) {
+ dput(dentry);
+ break;
+ }
+ }
+next:
+ dput(dentry);
+ spin_lock(&dcache_lock);
+ next = next->next;
+ }
+
+ if ( expired ) {
+ DPRINTK("returning %p %.*s",
+ expired, (int)expired->d_name.len, expired->d_name.name);
+ spin_lock(&dcache_lock);
+ list_del(&expired->d_parent->d_subdirs);
+ list_add(&expired->d_parent->d_subdirs, &expired->d_child);
+ spin_unlock(&dcache_lock);
+ return expired;
+ }
+ spin_unlock(&dcache_lock);
+
+ return NULL;
+}
+
+/* Perform an expiry operation */
+int autofs4_expire_run(struct super_block *sb,
+ struct vfsmount *mnt,
+ struct autofs_sb_info *sbi,
+ struct autofs_packet_expire __user *pkt_p)
+{
+ struct autofs_packet_expire pkt;
+ struct dentry *dentry;
+
+ memset(&pkt,0,sizeof pkt);
+
+ pkt.hdr.proto_version = sbi->version;
+ pkt.hdr.type = autofs_ptype_expire;
+
+ if ((dentry = autofs4_expire(sb, mnt, sbi, 0)) == NULL)
+ return -EAGAIN;
+
+ pkt.len = dentry->d_name.len;
+ memcpy(pkt.name, dentry->d_name.name, pkt.len);
+ pkt.name[pkt.len] = '\0';
+ dput(dentry);
+
+ if ( copy_to_user(pkt_p, &pkt, sizeof(struct autofs_packet_expire)) )
+ return -EFAULT;
+
+ return 0;
+}
+
+/* Call repeatedly until it returns -EAGAIN, meaning there's nothing
+ more to be done */
+int autofs4_expire_multi(struct super_block *sb, struct vfsmount *mnt,
+ struct autofs_sb_info *sbi, int __user *arg)
+{
+ struct dentry *dentry;
+ int ret = -EAGAIN;
+ int do_now = 0;
+
+ if (arg && get_user(do_now, arg))
+ return -EFAULT;
+
+ if ((dentry = autofs4_expire(sb, mnt, sbi, do_now)) != NULL) {
+ struct autofs_info *de_info = autofs4_dentry_ino(dentry);
+
+ /* This is synchronous because it makes the daemon a
+ little easier */
+ de_info->flags |= AUTOFS_INF_EXPIRING;
+ ret = autofs4_wait(sbi, dentry, NFY_EXPIRE);
+ de_info->flags &= ~AUTOFS_INF_EXPIRING;
+ dput(dentry);
+ }
+
+ return ret;
+}
+
diff --git a/fs/autofs4/init.c b/fs/autofs4/init.c
new file mode 100644
index 000000000000..acecec8578ce
--- /dev/null
+++ b/fs/autofs4/init.c
@@ -0,0 +1,42 @@
+/* -*- c -*- --------------------------------------------------------------- *
+ *
+ * linux/fs/autofs/init.c
+ *
+ * Copyright 1997-1998 Transmeta Corporation -- All Rights Reserved
+ *
+ * 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
+ * option, any later version, incorporated herein by reference.
+ *
+ * ------------------------------------------------------------------------- */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include "autofs_i.h"
+
+static struct super_block *autofs_get_sb(struct file_system_type *fs_type,
+ int flags, const char *dev_name, void *data)
+{
+ return get_sb_nodev(fs_type, flags, data, autofs4_fill_super);
+}
+
+static struct file_system_type autofs_fs_type = {
+ .owner = THIS_MODULE,
+ .name = "autofs",
+ .get_sb = autofs_get_sb,
+ .kill_sb = kill_anon_super,
+};
+
+static int __init init_autofs4_fs(void)
+{
+ return register_filesystem(&autofs_fs_type);
+}
+
+static void __exit exit_autofs4_fs(void)
+{
+ unregister_filesystem(&autofs_fs_type);
+}
+
+module_init(init_autofs4_fs)
+module_exit(exit_autofs4_fs)
+MODULE_LICENSE("GPL");
diff --git a/fs/autofs4/inode.c b/fs/autofs4/inode.c
new file mode 100644
index 000000000000..a52560746628
--- /dev/null
+++ b/fs/autofs4/inode.c
@@ -0,0 +1,324 @@
+/* -*- c -*- --------------------------------------------------------------- *
+ *
+ * linux/fs/autofs/inode.c
+ *
+ * Copyright 1997-1998 Transmeta Corporation -- All Rights Reserved
+ *
+ * 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
+ * option, any later version, incorporated herein by reference.
+ *
+ * ------------------------------------------------------------------------- */
+
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/file.h>
+#include <linux/pagemap.h>
+#include <linux/parser.h>
+#include <linux/bitops.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;
+ }
+}
+
+struct autofs_info *autofs4_init_ino(struct autofs_info *ino,
+ struct autofs_sb_info *sbi, mode_t mode)
+{
+ int reinit = 1;
+
+ if (ino == NULL) {
+ reinit = 0;
+ ino = kmalloc(sizeof(*ino), GFP_KERNEL);
+ }
+
+ if (ino == NULL)
+ return NULL;
+
+ ino->flags = 0;
+ ino->mode = mode;
+ ino->inode = NULL;
+ ino->dentry = NULL;
+ ino->size = 0;
+
+ ino->last_used = jiffies;
+
+ ino->sbi = sbi;
+
+ if (reinit && ino->free)
+ (ino->free)(ino);
+
+ memset(&ino->u, 0, sizeof(ino->u));
+
+ ino->free = NULL;
+
+ if (S_ISLNK(mode))
+ ino->free = ino_lnkfree;
+
+ return ino;
+}
+
+void autofs4_free_ino(struct autofs_info *ino)
+{
+ if (ino->dentry) {
+ ino->dentry->d_fsdata = NULL;
+ if (ino->dentry->d_inode)
+ dput(ino->dentry);
+ ino->dentry = NULL;
+ }
+ if (ino->free)
+ (ino->free)(ino);
+ kfree(ino);
+}
+
+static void autofs4_put_super(struct super_block *sb)
+{
+ struct autofs_sb_info *sbi = autofs4_sbi(sb);
+
+ sb->s_fs_info = NULL;
+
+ if ( !sbi->catatonic )
+ autofs4_catatonic_mode(sbi); /* Free wait queues, close pipe */
+
+ kfree(sbi);
+
+ DPRINTK("shutting down");
+}
+
+static struct super_operations autofs4_sops = {
+ .put_super = autofs4_put_super,
+ .statfs = simple_statfs,
+};
+
+enum {Opt_err, Opt_fd, Opt_uid, Opt_gid, Opt_pgrp, Opt_minproto, Opt_maxproto};
+
+static match_table_t tokens = {
+ {Opt_fd, "fd=%u"},
+ {Opt_uid, "uid=%u"},
+ {Opt_gid, "gid=%u"},
+ {Opt_pgrp, "pgrp=%u"},
+ {Opt_minproto, "minproto=%u"},
+ {Opt_maxproto, "maxproto=%u"},
+ {Opt_err, NULL}
+};
+
+static int parse_options(char *options, int *pipefd, uid_t *uid, gid_t *gid,
+ pid_t *pgrp, int *minproto, int *maxproto)
+{
+ char *p;
+ substring_t args[MAX_OPT_ARGS];
+ int option;
+
+ *uid = current->uid;
+ *gid = current->gid;
+ *pgrp = process_group(current);
+
+ *minproto = AUTOFS_MIN_PROTO_VERSION;
+ *maxproto = AUTOFS_MAX_PROTO_VERSION;
+
+ *pipefd = -1;
+
+ if (!options)
+ return 1;
+
+ while ((p = strsep(&options, ",")) != NULL) {
+ int token;
+ if (!*p)
+ continue;
+
+ token = match_token(p, tokens, args);
+ switch (token) {
+ case Opt_fd:
+ if (match_int(args, pipefd))
+ return 1;
+ break;
+ case Opt_uid:
+ if (match_int(args, &option))
+ return 1;
+ *uid = option;
+ break;
+ case Opt_gid:
+ if (match_int(args, &option))
+ return 1;
+ *gid = option;
+ break;
+ case Opt_pgrp:
+ if (match_int(args, &option))
+ return 1;
+ *pgrp = option;
+ break;
+ case Opt_minproto:
+ if (match_int(args, &option))
+ return 1;
+ *minproto = option;
+ break;
+ case Opt_maxproto:
+ if (match_int(args, &option))
+ return 1;
+ *maxproto = option;
+ break;
+ default:
+ return 1;
+ }
+ }
+ return (*pipefd < 0);
+}
+
+static struct autofs_info *autofs4_mkroot(struct autofs_sb_info *sbi)
+{
+ struct autofs_info *ino;
+
+ ino = autofs4_init_ino(NULL, sbi, S_IFDIR | 0755);
+ if (!ino)
+ return NULL;
+
+ return ino;
+}
+
+int autofs4_fill_super(struct super_block *s, void *data, int silent)
+{
+ struct inode * root_inode;
+ struct dentry * root;
+ struct file * pipe;
+ 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 )
+ goto fail_unlock;
+ DPRINTK("starting up, sbi = %p",sbi);
+
+ memset(sbi, 0, sizeof(*sbi));
+
+ s->s_fs_info = sbi;
+ sbi->magic = AUTOFS_SBI_MAGIC;
+ 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->queues = NULL;
+ s->s_blocksize = 1024;
+ s->s_blocksize_bits = 10;
+ s->s_magic = AUTOFS_SUPER_MAGIC;
+ s->s_op = &autofs4_sops;
+ s->s_time_gran = 1;
+
+ /*
+ * Get the root inode and dentry, but defer checking for errors.
+ */
+ ino = autofs4_mkroot(sbi);
+ if (!ino)
+ goto fail_free;
+ root_inode = autofs4_get_inode(s, ino);
+ kfree(ino);
+ if (!root_inode)
+ goto fail_free;
+
+ 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;
+
+ /* Can this call block? */
+ if (parse_options(data, &pipefd,
+ &root_inode->i_uid, &root_inode->i_gid,
+ &sbi->oz_pgrp,
+ &minproto, &maxproto)) {
+ printk("autofs: called with bogus options\n");
+ goto fail_dput;
+ }
+
+ /* Couldn't this be tested earlier? */
+ if (maxproto < AUTOFS_MIN_PROTO_VERSION ||
+ minproto > AUTOFS_MAX_PROTO_VERSION) {
+ printk("autofs: kernel does not match daemon version "
+ "daemon (%d, %d) kernel (%d, %d)\n",
+ minproto, maxproto,
+ AUTOFS_MIN_PROTO_VERSION, AUTOFS_MAX_PROTO_VERSION);
+ goto fail_dput;
+ }
+
+ sbi->version = maxproto > AUTOFS_MAX_PROTO_VERSION ? AUTOFS_MAX_PROTO_VERSION : maxproto;
+ sbi->sub_version = AUTOFS_PROTO_SUBVERSION;
+
+ DPRINTK("pipe fd = %d, pgrp = %u", pipefd, sbi->oz_pgrp);
+ pipe = fget(pipefd);
+
+ if ( !pipe ) {
+ printk("autofs: could not open pipe file descriptor\n");
+ goto fail_dput;
+ }
+ if ( !pipe->f_op || !pipe->f_op->write )
+ goto fail_fput;
+ sbi->pipe = pipe;
+
+ /*
+ * Success! Install the root dentry now to indicate completion.
+ */
+ s->s_root = root;
+ return 0;
+
+ /*
+ * Failure ... clean up.
+ */
+fail_fput:
+ printk("autofs: pipe file descriptor does not contain proper ops\n");
+ fput(pipe);
+ /* fall through */
+fail_dput:
+ dput(root);
+ goto fail_free;
+fail_iput:
+ printk("autofs: get root dentry failed\n");
+ iput(root_inode);
+fail_free:
+ kfree(sbi);
+fail_unlock:
+ return -EINVAL;
+}
+
+struct inode *autofs4_get_inode(struct super_block *sb,
+ struct autofs_info *inf)
+{
+ struct inode *inode = new_inode(sb);
+
+ if (inode == NULL)
+ return NULL;
+
+ inf->inode = inode;
+ inode->i_mode = inf->mode;
+ if (sb->s_root) {
+ inode->i_uid = sb->s_root->d_inode->i_uid;
+ inode->i_gid = sb->s_root->d_inode->i_gid;
+ } else {
+ inode->i_uid = 0;
+ inode->i_gid = 0;
+ }
+ inode->i_blksize = PAGE_CACHE_SIZE;
+ inode->i_blocks = 0;
+ inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
+
+ if (S_ISDIR(inf->mode)) {
+ inode->i_nlink = 2;
+ inode->i_op = &autofs4_dir_inode_operations;
+ inode->i_fop = &autofs4_dir_operations;
+ } else if (S_ISLNK(inf->mode)) {
+ inode->i_size = inf->size;
+ inode->i_op = &autofs4_symlink_inode_operations;
+ }
+
+ return inode;
+}
diff --git a/fs/autofs4/root.c b/fs/autofs4/root.c
new file mode 100644
index 000000000000..3765c047f157
--- /dev/null
+++ b/fs/autofs4/root.c
@@ -0,0 +1,808 @@
+/* -*- c -*- --------------------------------------------------------------- *
+ *
+ * linux/fs/autofs/root.c
+ *
+ * Copyright 1997-1998 Transmeta Corporation -- All Rights Reserved
+ * Copyright 1999-2000 Jeremy Fitzhardinge <jeremy@goop.org>
+ * Copyright 2001-2003 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
+ * option, any later version, incorporated herein by reference.
+ *
+ * ------------------------------------------------------------------------- */
+
+#include <linux/errno.h>
+#include <linux/stat.h>
+#include <linux/param.h>
+#include <linux/time.h>
+#include <linux/smp_lock.h>
+#include "autofs_i.h"
+
+static int autofs4_dir_symlink(struct inode *,struct dentry *,const char *);
+static int autofs4_dir_unlink(struct inode *,struct dentry *);
+static int autofs4_dir_rmdir(struct inode *,struct dentry *);
+static int autofs4_dir_mkdir(struct inode *,struct dentry *,int);
+static int autofs4_root_ioctl(struct inode *, struct file *,unsigned int,unsigned long);
+static int autofs4_dir_open(struct inode *inode, struct file *file);
+static int autofs4_dir_close(struct inode *inode, struct file *file);
+static int autofs4_dir_readdir(struct file * filp, void * dirent, filldir_t filldir);
+static int autofs4_root_readdir(struct file * filp, void * dirent, filldir_t filldir);
+static struct dentry *autofs4_lookup(struct inode *,struct dentry *, struct nameidata *);
+static int autofs4_dcache_readdir(struct file *, void *, filldir_t);
+
+struct file_operations autofs4_root_operations = {
+ .open = dcache_dir_open,
+ .release = dcache_dir_close,
+ .read = generic_read_dir,
+ .readdir = autofs4_root_readdir,
+ .ioctl = autofs4_root_ioctl,
+};
+
+struct file_operations autofs4_dir_operations = {
+ .open = autofs4_dir_open,
+ .release = autofs4_dir_close,
+ .read = generic_read_dir,
+ .readdir = autofs4_dir_readdir,
+};
+
+struct inode_operations autofs4_root_inode_operations = {
+ .lookup = autofs4_lookup,
+ .unlink = autofs4_dir_unlink,
+ .symlink = autofs4_dir_symlink,
+ .mkdir = autofs4_dir_mkdir,
+ .rmdir = autofs4_dir_rmdir,
+};
+
+struct inode_operations autofs4_dir_inode_operations = {
+ .lookup = autofs4_lookup,
+ .unlink = autofs4_dir_unlink,
+ .symlink = autofs4_dir_symlink,
+ .mkdir = autofs4_dir_mkdir,
+ .rmdir = autofs4_dir_rmdir,
+};
+
+static int autofs4_root_readdir(struct file *file, void *dirent,
+ filldir_t filldir)
+{
+ struct autofs_sb_info *sbi = autofs4_sbi(file->f_dentry->d_sb);
+ int oz_mode = autofs4_oz_mode(sbi);
+
+ DPRINTK("called, filp->f_pos = %lld", file->f_pos);
+
+ /*
+ * Don't set reghost flag if:
+ * 1) f_pos is larger than zero -- we've already been here.
+ * 2) we haven't even enabled reghosting in the 1st place.
+ * 3) this is the daemon doing a readdir
+ */
+ if (oz_mode && file->f_pos == 0 && sbi->reghost_enabled)
+ sbi->needs_reghost = 1;
+
+ DPRINTK("needs_reghost = %d", sbi->needs_reghost);
+
+ return autofs4_dcache_readdir(file, dirent, filldir);
+}
+
+/* Update usage from here to top of tree, so that scan of
+ top-level directories will give a useful result */
+static void autofs4_update_usage(struct dentry *dentry)
+{
+ struct dentry *top = dentry->d_sb->s_root;
+
+ spin_lock(&dcache_lock);
+ for(; dentry != top; dentry = dentry->d_parent) {
+ struct autofs_info *ino = autofs4_dentry_ino(dentry);
+
+ if (ino) {
+ update_atime(dentry->d_inode);
+ ino->last_used = jiffies;
+ }
+ }
+ spin_unlock(&dcache_lock);
+}
+
+/*
+ * From 2.4 kernel readdir.c
+ */
+static int autofs4_dcache_readdir(struct file * filp, void * dirent, filldir_t filldir)
+{
+ int i;
+ struct dentry *dentry = filp->f_dentry;
+
+ i = filp->f_pos;
+ switch (i) {
+ case 0:
+ if (filldir(dirent, ".", 1, i, dentry->d_inode->i_ino, DT_DIR) < 0)
+ break;
+ i++;
+ filp->f_pos++;
+ /* fallthrough */
+ case 1:
+ if (filldir(dirent, "..", 2, i, dentry->d_parent->d_inode->i_ino, DT_DIR) < 0)
+ break;
+ i++;
+ filp->f_pos++;
+ /* fallthrough */
+ default: {
+ struct list_head *list;
+ int j = i-2;
+
+ spin_lock(&dcache_lock);
+ list = dentry->d_subdirs.next;
+
+ for (;;) {
+ if (list == &dentry->d_subdirs) {
+ spin_unlock(&dcache_lock);
+ return 0;
+ }
+ if (!j)
+ break;
+ j--;
+ list = list->next;
+ }
+
+ while(1) {
+ struct dentry *de = list_entry(list, struct dentry, d_child);
+
+ if (!d_unhashed(de) && de->d_inode) {
+ spin_unlock(&dcache_lock);
+ if (filldir(dirent, de->d_name.name, de->d_name.len, filp->f_pos, de->d_inode->i_ino, DT_UNKNOWN) < 0)
+ break;
+ spin_lock(&dcache_lock);
+ }
+ filp->f_pos++;
+ list = list->next;
+ if (list != &dentry->d_subdirs)
+ continue;
+ spin_unlock(&dcache_lock);
+ break;
+ }
+ }
+ }
+ return 0;
+}
+
+static int autofs4_dir_open(struct inode *inode, struct file *file)
+{
+ struct dentry *dentry = file->f_dentry;
+ struct vfsmount *mnt = file->f_vfsmnt;
+ struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);
+ int status;
+
+ DPRINTK("file=%p dentry=%p %.*s",
+ file, dentry, dentry->d_name.len, dentry->d_name.name);
+
+ if (autofs4_oz_mode(sbi))
+ goto out;
+
+ if (autofs4_ispending(dentry)) {
+ DPRINTK("dentry busy");
+ return -EBUSY;
+ }
+
+ if (!d_mountpoint(dentry) && dentry->d_op && dentry->d_op->d_revalidate) {
+ struct nameidata nd;
+ int empty;
+
+ /* In case there are stale directory dentrys from a failed mount */
+ spin_lock(&dcache_lock);
+ empty = list_empty(&dentry->d_subdirs);
+ spin_unlock(&dcache_lock);
+
+ if (!empty)
+ d_invalidate(dentry);
+
+ nd.flags = LOOKUP_DIRECTORY;
+ status = (dentry->d_op->d_revalidate)(dentry, &nd);
+
+ if (!status)
+ return -ENOENT;
+ }
+
+ if (d_mountpoint(dentry)) {
+ struct file *fp = NULL;
+ struct vfsmount *fp_mnt = mntget(mnt);
+ struct dentry *fp_dentry = dget(dentry);
+
+ while (follow_down(&fp_mnt, &fp_dentry) && d_mountpoint(fp_dentry));
+
+ fp = dentry_open(fp_dentry, fp_mnt, file->f_flags);
+ status = PTR_ERR(fp);
+ if (IS_ERR(fp)) {
+ file->private_data = NULL;
+ return status;
+ }
+ file->private_data = fp;
+ }
+out:
+ return 0;
+}
+
+static int autofs4_dir_close(struct inode *inode, struct file *file)
+{
+ struct dentry *dentry = file->f_dentry;
+ struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);
+
+ DPRINTK("file=%p dentry=%p %.*s",
+ file, dentry, dentry->d_name.len, dentry->d_name.name);
+
+ if (autofs4_oz_mode(sbi))
+ goto out;
+
+ if (autofs4_ispending(dentry)) {
+ DPRINTK("dentry busy");
+ return -EBUSY;
+ }
+
+ if (d_mountpoint(dentry)) {
+ struct file *fp = file->private_data;
+
+ if (!fp)
+ return -ENOENT;
+
+ filp_close(fp, current->files);
+ file->private_data = NULL;
+ }
+out:
+ return 0;
+}
+
+static int autofs4_dir_readdir(struct file *file, void *dirent, filldir_t filldir)
+{
+ struct dentry *dentry = file->f_dentry;
+ struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);
+ int status;
+
+ DPRINTK("file=%p dentry=%p %.*s",
+ file, dentry, dentry->d_name.len, dentry->d_name.name);
+
+ if (autofs4_oz_mode(sbi))
+ goto out;
+
+ if (autofs4_ispending(dentry)) {
+ DPRINTK("dentry busy");
+ return -EBUSY;
+ }
+
+ if (d_mountpoint(dentry)) {
+ struct file *fp = file->private_data;
+
+ if (!fp)
+ return -ENOENT;
+
+ if (!fp->f_op || !fp->f_op->readdir)
+ goto out;
+
+ status = vfs_readdir(fp, filldir, dirent);
+ file->f_pos = fp->f_pos;
+ if (status)
+ autofs4_copy_atime(file, fp);
+ return status;
+ }
+out:
+ return autofs4_dcache_readdir(file, dirent, filldir);
+}
+
+static int try_to_fill_dentry(struct dentry *dentry,
+ struct super_block *sb,
+ struct autofs_sb_info *sbi, int flags)
+{
+ struct autofs_info *de_info = autofs4_dentry_ino(dentry);
+ int status = 0;
+
+ /* Block on any pending expiry here; invalidate the dentry
+ when expiration is done to trigger mount request with a new
+ dentry */
+ if (de_info && (de_info->flags & AUTOFS_INF_EXPIRING)) {
+ DPRINTK("waiting for expire %p name=%.*s",
+ dentry, dentry->d_name.len, dentry->d_name.name);
+
+ status = autofs4_wait(sbi, dentry, NFY_NONE);
+
+ DPRINTK("expire done status=%d", status);
+
+ return 0;
+ }
+
+ DPRINTK("dentry=%p %.*s ino=%p",
+ dentry, dentry->d_name.len, dentry->d_name.name, dentry->d_inode);
+
+ /* Wait for a pending mount, triggering one if there isn't one already */
+ if (dentry->d_inode == NULL) {
+ DPRINTK("waiting for mount name=%.*s",
+ dentry->d_name.len, dentry->d_name.name);
+
+ status = autofs4_wait(sbi, dentry, NFY_MOUNT);
+
+ DPRINTK("mount done status=%d", status);
+
+ if (status && dentry->d_inode)
+ return 0; /* Try to get the kernel to invalidate this dentry */
+
+ /* Turn this into a real negative dentry? */
+ if (status == -ENOENT) {
+ dentry->d_time = jiffies + AUTOFS_NEGATIVE_TIMEOUT;
+ spin_lock(&dentry->d_lock);
+ dentry->d_flags &= ~DCACHE_AUTOFS_PENDING;
+ spin_unlock(&dentry->d_lock);
+ return 1;
+ } else if (status) {
+ /* Return a negative dentry, but leave it "pending" */
+ return 1;
+ }
+ /* Trigger mount for path component or follow link */
+ } else if (flags & (LOOKUP_CONTINUE | LOOKUP_DIRECTORY) ||
+ current->link_count) {
+ DPRINTK("waiting for mount name=%.*s",
+ dentry->d_name.len, dentry->d_name.name);
+
+ spin_lock(&dentry->d_lock);
+ dentry->d_flags |= DCACHE_AUTOFS_PENDING;
+ spin_unlock(&dentry->d_lock);
+ status = autofs4_wait(sbi, dentry, NFY_MOUNT);
+
+ DPRINTK("mount done status=%d", status);
+
+ if (status) {
+ spin_lock(&dentry->d_lock);
+ dentry->d_flags &= ~DCACHE_AUTOFS_PENDING;
+ spin_unlock(&dentry->d_lock);
+ return 0;
+ }
+ }
+
+ /* We don't update the usages for the autofs daemon itself, this
+ is necessary for recursive autofs mounts */
+ if (!autofs4_oz_mode(sbi))
+ autofs4_update_usage(dentry);
+
+ spin_lock(&dentry->d_lock);
+ dentry->d_flags &= ~DCACHE_AUTOFS_PENDING;
+ spin_unlock(&dentry->d_lock);
+ return 1;
+}
+
+/*
+ * Revalidate is called on every cache lookup. Some of those
+ * cache lookups may actually happen while the dentry is not
+ * yet completely filled in, and revalidate has to delay such
+ * lookups..
+ */
+static int autofs4_revalidate(struct dentry * dentry, struct nameidata *nd)
+{
+ struct inode * dir = dentry->d_parent->d_inode;
+ struct autofs_sb_info *sbi = autofs4_sbi(dir->i_sb);
+ int oz_mode = autofs4_oz_mode(sbi);
+ int flags = nd ? nd->flags : 0;
+ int status = 1;
+
+ /* Pending dentry */
+ if (autofs4_ispending(dentry)) {
+ if (!oz_mode)
+ status = try_to_fill_dentry(dentry, dir->i_sb, sbi, flags);
+ return status;
+ }
+
+ /* Negative dentry.. invalidate if "old" */
+ if (dentry->d_inode == NULL)
+ return (dentry->d_time - jiffies <= AUTOFS_NEGATIVE_TIMEOUT);
+
+ /* Check for a non-mountpoint directory with no contents */
+ spin_lock(&dcache_lock);
+ if (S_ISDIR(dentry->d_inode->i_mode) &&
+ !d_mountpoint(dentry) &&
+ list_empty(&dentry->d_subdirs)) {
+ DPRINTK("dentry=%p %.*s, emptydir",
+ dentry, dentry->d_name.len, dentry->d_name.name);
+ spin_unlock(&dcache_lock);
+ if (!oz_mode)
+ status = try_to_fill_dentry(dentry, dir->i_sb, sbi, flags);
+ return status;
+ }
+ spin_unlock(&dcache_lock);
+
+ /* Update the usage list */
+ if (!oz_mode)
+ autofs4_update_usage(dentry);
+
+ return 1;
+}
+
+static void autofs4_dentry_release(struct dentry *de)
+{
+ struct autofs_info *inf;
+
+ DPRINTK("releasing %p", de);
+
+ inf = autofs4_dentry_ino(de);
+ de->d_fsdata = NULL;
+
+ if (inf) {
+ inf->dentry = NULL;
+ inf->inode = NULL;
+
+ autofs4_free_ino(inf);
+ }
+}
+
+/* For dentries of directories in the root dir */
+static struct dentry_operations autofs4_root_dentry_operations = {
+ .d_revalidate = autofs4_revalidate,
+ .d_release = autofs4_dentry_release,
+};
+
+/* For other dentries */
+static struct dentry_operations autofs4_dentry_operations = {
+ .d_revalidate = autofs4_revalidate,
+ .d_release = autofs4_dentry_release,
+};
+
+/* Lookups in the root directory */
+static struct dentry *autofs4_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd)
+{
+ struct autofs_sb_info *sbi;
+ int oz_mode;
+
+ DPRINTK("name = %.*s",
+ dentry->d_name.len, dentry->d_name.name);
+
+ if (dentry->d_name.len > NAME_MAX)
+ return ERR_PTR(-ENAMETOOLONG);/* File name too long to exist */
+
+ sbi = autofs4_sbi(dir->i_sb);
+
+ oz_mode = autofs4_oz_mode(sbi);
+ DPRINTK("pid = %u, pgrp = %u, catatonic = %d, oz_mode = %d",
+ current->pid, process_group(current), sbi->catatonic, oz_mode);
+
+ /*
+ * Mark the dentry incomplete, but add it. This is needed so
+ * that the VFS layer knows about the dentry, and we can count
+ * on catching any lookups through the revalidate.
+ *
+ * Let all the hard work be done by the revalidate function that
+ * needs to be able to do this anyway..
+ *
+ * We need to do this before we release the directory semaphore.
+ */
+ dentry->d_op = &autofs4_root_dentry_operations;
+
+ if (!oz_mode) {
+ spin_lock(&dentry->d_lock);
+ dentry->d_flags |= DCACHE_AUTOFS_PENDING;
+ spin_unlock(&dentry->d_lock);
+ }
+ dentry->d_fsdata = NULL;
+ d_add(dentry, NULL);
+
+ if (dentry->d_op && dentry->d_op->d_revalidate) {
+ up(&dir->i_sem);
+ (dentry->d_op->d_revalidate)(dentry, nd);
+ down(&dir->i_sem);
+ }
+
+ /*
+ * If we are still pending, check if we had to handle
+ * a signal. If so we can force a restart..
+ */
+ if (dentry->d_flags & DCACHE_AUTOFS_PENDING) {
+ /* See if we were interrupted */
+ if (signal_pending(current)) {
+ sigset_t *sigset = &current->pending.signal;
+ if (sigismember (sigset, SIGKILL) ||
+ sigismember (sigset, SIGQUIT) ||
+ sigismember (sigset, SIGINT)) {
+ return ERR_PTR(-ERESTARTNOINTR);
+ }
+ }
+ }
+
+ /*
+ * If this dentry is unhashed, then we shouldn't honour this
+ * lookup even if the dentry is positive. Returning ENOENT here
+ * doesn't do the right thing for all system calls, but it should
+ * be OK for the operations we permit from an autofs.
+ */
+ if ( dentry->d_inode && d_unhashed(dentry) )
+ return ERR_PTR(-ENOENT);
+
+ return NULL;
+}
+
+static int autofs4_dir_symlink(struct inode *dir,
+ struct dentry *dentry,
+ const char *symname)
+{
+ struct autofs_sb_info *sbi = autofs4_sbi(dir->i_sb);
+ struct autofs_info *ino = autofs4_dentry_ino(dentry);
+ struct inode *inode;
+ char *cp;
+
+ DPRINTK("%s <- %.*s", symname,
+ dentry->d_name.len, dentry->d_name.name);
+
+ if (!autofs4_oz_mode(sbi))
+ return -EACCES;
+
+ ino = autofs4_init_ino(ino, sbi, S_IFLNK | 0555);
+ if (ino == NULL)
+ return -ENOSPC;
+
+ ino->size = strlen(symname);
+ ino->u.symlink = cp = kmalloc(ino->size + 1, GFP_KERNEL);
+
+ if (cp == NULL) {
+ kfree(ino);
+ return -ENOSPC;
+ }
+
+ strcpy(cp, symname);
+
+ inode = autofs4_get_inode(dir->i_sb, ino);
+ d_instantiate(dentry, inode);
+
+ if (dir == dir->i_sb->s_root->d_inode)
+ dentry->d_op = &autofs4_root_dentry_operations;
+ else
+ dentry->d_op = &autofs4_dentry_operations;
+
+ dentry->d_fsdata = ino;
+ ino->dentry = dget(dentry);
+ ino->inode = inode;
+
+ dir->i_mtime = CURRENT_TIME;
+
+ return 0;
+}
+
+/*
+ * NOTE!
+ *
+ * Normal filesystems would do a "d_delete()" to tell the VFS dcache
+ * that the file no longer exists. However, doing that means that the
+ * VFS layer can turn the dentry into a negative dentry. We don't want
+ * this, because since the unlink is probably the result of an expire.
+ * We simply d_drop it, which allows the dentry lookup to remount it
+ * if necessary.
+ *
+ * If a process is blocked on the dentry waiting for the expire to finish,
+ * it will invalidate the dentry and try to mount with a new one.
+ *
+ * Also see autofs4_dir_rmdir()..
+ */
+static int autofs4_dir_unlink(struct inode *dir, struct dentry *dentry)
+{
+ struct autofs_sb_info *sbi = autofs4_sbi(dir->i_sb);
+ struct autofs_info *ino = autofs4_dentry_ino(dentry);
+
+ /* This allows root to remove symlinks */
+ if ( !autofs4_oz_mode(sbi) && !capable(CAP_SYS_ADMIN) )
+ return -EACCES;
+
+ dput(ino->dentry);
+
+ dentry->d_inode->i_size = 0;
+ dentry->d_inode->i_nlink = 0;
+
+ dir->i_mtime = CURRENT_TIME;
+
+ d_drop(dentry);
+
+ return 0;
+}
+
+static int autofs4_dir_rmdir(struct inode *dir, struct dentry *dentry)
+{
+ struct autofs_sb_info *sbi = autofs4_sbi(dir->i_sb);
+ struct autofs_info *ino = autofs4_dentry_ino(dentry);
+
+ if (!autofs4_oz_mode(sbi))
+ return -EACCES;
+
+ spin_lock(&dcache_lock);
+ if (!list_empty(&dentry->d_subdirs)) {
+ spin_unlock(&dcache_lock);
+ return -ENOTEMPTY;
+ }
+ spin_lock(&dentry->d_lock);
+ __d_drop(dentry);
+ spin_unlock(&dentry->d_lock);
+ spin_unlock(&dcache_lock);
+
+ dput(ino->dentry);
+
+ dentry->d_inode->i_size = 0;
+ dentry->d_inode->i_nlink = 0;
+
+ if (dir->i_nlink)
+ dir->i_nlink--;
+
+ return 0;
+}
+
+static int autofs4_dir_mkdir(struct inode *dir, struct dentry *dentry, int mode)
+{
+ struct autofs_sb_info *sbi = autofs4_sbi(dir->i_sb);
+ struct autofs_info *ino = autofs4_dentry_ino(dentry);
+ struct inode *inode;
+
+ if ( !autofs4_oz_mode(sbi) )
+ return -EACCES;
+
+ DPRINTK("dentry %p, creating %.*s",
+ dentry, dentry->d_name.len, dentry->d_name.name);
+
+ ino = autofs4_init_ino(ino, sbi, S_IFDIR | 0555);
+ if (ino == NULL)
+ return -ENOSPC;
+
+ inode = autofs4_get_inode(dir->i_sb, ino);
+ d_instantiate(dentry, inode);
+
+ if (dir == dir->i_sb->s_root->d_inode)
+ dentry->d_op = &autofs4_root_dentry_operations;
+ else
+ dentry->d_op = &autofs4_dentry_operations;
+
+ dentry->d_fsdata = ino;
+ ino->dentry = dget(dentry);
+ ino->inode = inode;
+ dir->i_nlink++;
+ dir->i_mtime = CURRENT_TIME;
+
+ return 0;
+}
+
+/* Get/set timeout ioctl() operation */
+static inline int autofs4_get_set_timeout(struct autofs_sb_info *sbi,
+ unsigned long __user *p)
+{
+ int rv;
+ unsigned long ntimeout;
+
+ if ( (rv = get_user(ntimeout, p)) ||
+ (rv = put_user(sbi->exp_timeout/HZ, p)) )
+ return rv;
+
+ if ( ntimeout > ULONG_MAX/HZ )
+ sbi->exp_timeout = 0;
+ else
+ sbi->exp_timeout = ntimeout * HZ;
+
+ return 0;
+}
+
+/* Return protocol version */
+static inline int autofs4_get_protover(struct autofs_sb_info *sbi, int __user *p)
+{
+ return put_user(sbi->version, p);
+}
+
+/* Return protocol sub version */
+static inline int autofs4_get_protosubver(struct autofs_sb_info *sbi, int __user *p)
+{
+ return put_user(sbi->sub_version, p);
+}
+
+/*
+ * Tells the daemon whether we need to reghost or not. Also, clears
+ * the reghost_needed flag.
+ */
+static inline int autofs4_ask_reghost(struct autofs_sb_info *sbi, int __user *p)
+{
+ int status;
+
+ DPRINTK("returning %d", sbi->needs_reghost);
+
+ status = put_user(sbi->needs_reghost, p);
+ if ( status )
+ return status;
+
+ sbi->needs_reghost = 0;
+ return 0;
+}
+
+/*
+ * Enable / Disable reghosting ioctl() operation
+ */
+static inline int autofs4_toggle_reghost(struct autofs_sb_info *sbi, int __user *p)
+{
+ int status;
+ int val;
+
+ status = get_user(val, p);
+
+ DPRINTK("reghost = %d", val);
+
+ if (status)
+ return status;
+
+ /* turn on/off reghosting, with the val */
+ sbi->reghost_enabled = val;
+ return 0;
+}
+
+/*
+* Tells the daemon whether it can umount the autofs mount.
+*/
+static inline int autofs4_ask_umount(struct vfsmount *mnt, int __user *p)
+{
+ int status = 0;
+
+ if (may_umount(mnt) == 0)
+ status = 1;
+
+ DPRINTK("returning %d", status);
+
+ status = put_user(status, p);
+
+ return status;
+}
+
+/* Identify autofs4_dentries - this is so we can tell if there's
+ an extra dentry refcount or not. We only hold a refcount on the
+ dentry if its non-negative (ie, d_inode != NULL)
+*/
+int is_autofs4_dentry(struct dentry *dentry)
+{
+ return dentry && dentry->d_inode &&
+ (dentry->d_op == &autofs4_root_dentry_operations ||
+ dentry->d_op == &autofs4_dentry_operations) &&
+ dentry->d_fsdata != NULL;
+}
+
+/*
+ * ioctl()'s on the root directory is the chief method for the daemon to
+ * generate kernel reactions
+ */
+static int autofs4_root_ioctl(struct inode *inode, struct file *filp,
+ unsigned int cmd, unsigned long arg)
+{
+ struct autofs_sb_info *sbi = autofs4_sbi(inode->i_sb);
+ void __user *p = (void __user *)arg;
+
+ DPRINTK("cmd = 0x%08x, arg = 0x%08lx, sbi = %p, pgrp = %u",
+ cmd,arg,sbi,process_group(current));
+
+ if ( _IOC_TYPE(cmd) != _IOC_TYPE(AUTOFS_IOC_FIRST) ||
+ _IOC_NR(cmd) - _IOC_NR(AUTOFS_IOC_FIRST) >= AUTOFS_IOC_COUNT )
+ return -ENOTTY;
+
+ if ( !autofs4_oz_mode(sbi) && !capable(CAP_SYS_ADMIN) )
+ return -EPERM;
+
+ switch(cmd) {
+ case AUTOFS_IOC_READY: /* Wait queue: go ahead and retry */
+ return autofs4_wait_release(sbi,(autofs_wqt_t)arg,0);
+ case AUTOFS_IOC_FAIL: /* Wait queue: fail with ENOENT */
+ return autofs4_wait_release(sbi,(autofs_wqt_t)arg,-ENOENT);
+ case AUTOFS_IOC_CATATONIC: /* Enter catatonic mode (daemon shutdown) */
+ autofs4_catatonic_mode(sbi);
+ return 0;
+ case AUTOFS_IOC_PROTOVER: /* Get protocol version */
+ return autofs4_get_protover(sbi, p);
+ case AUTOFS_IOC_PROTOSUBVER: /* Get protocol sub version */
+ return autofs4_get_protosubver(sbi, p);
+ case AUTOFS_IOC_SETTIMEOUT:
+ return autofs4_get_set_timeout(sbi, p);
+
+ case AUTOFS_IOC_TOGGLEREGHOST:
+ return autofs4_toggle_reghost(sbi, p);
+ case AUTOFS_IOC_ASKREGHOST:
+ return autofs4_ask_reghost(sbi, p);
+
+ case AUTOFS_IOC_ASKUMOUNT:
+ return autofs4_ask_umount(filp->f_vfsmnt, p);
+
+ /* return a single thing to expire */
+ case AUTOFS_IOC_EXPIRE:
+ return autofs4_expire_run(inode->i_sb,filp->f_vfsmnt,sbi, p);
+ /* same as above, but can send multiple expires through pipe */
+ case AUTOFS_IOC_EXPIRE_MULTI:
+ return autofs4_expire_multi(inode->i_sb,filp->f_vfsmnt,sbi, p);
+
+ default:
+ return -ENOSYS;
+ }
+}
diff --git a/fs/autofs4/symlink.c b/fs/autofs4/symlink.c
new file mode 100644
index 000000000000..c265a66edf0f
--- /dev/null
+++ b/fs/autofs4/symlink.c
@@ -0,0 +1,25 @@
+/* -*- c -*- --------------------------------------------------------------- *
+ *
+ * linux/fs/autofs/symlink.c
+ *
+ * Copyright 1997-1998 Transmeta Corporation -- All Rights Reserved
+ *
+ * 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
+ * option, any later version, incorporated herein by reference.
+ *
+ * ------------------------------------------------------------------------- */
+
+#include "autofs_i.h"
+
+static int autofs4_follow_link(struct dentry *dentry, struct nameidata *nd)
+{
+ struct autofs_info *ino = autofs4_dentry_ino(dentry);
+ nd_set_link(nd, (char *)ino->u.symlink);
+ return 0;
+}
+
+struct inode_operations autofs4_symlink_inode_operations = {
+ .readlink = generic_readlink,
+ .follow_link = autofs4_follow_link
+};
diff --git a/fs/autofs4/waitq.c b/fs/autofs4/waitq.c
new file mode 100644
index 000000000000..1ab24a662e09
--- /dev/null
+++ b/fs/autofs4/waitq.c
@@ -0,0 +1,303 @@
+/* -*- c -*- --------------------------------------------------------------- *
+ *
+ * linux/fs/autofs/waitq.c
+ *
+ * Copyright 1997-1998 Transmeta Corporation -- All Rights Reserved
+ * Copyright 2001-2003 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
+ * option, any later version, incorporated herein by reference.
+ *
+ * ------------------------------------------------------------------------- */
+
+#include <linux/slab.h>
+#include <linux/time.h>
+#include <linux/signal.h>
+#include <linux/file.h>
+#include "autofs_i.h"
+
+/* We make this a static variable rather than a part of the superblock; it
+ is better if we don't reassign numbers easily even across filesystems */
+static autofs_wqt_t autofs4_next_wait_queue = 1;
+
+/* These are the signals we allow interrupting a pending mount */
+#define SHUTDOWN_SIGS (sigmask(SIGKILL) | sigmask(SIGINT) | sigmask(SIGQUIT))
+
+void autofs4_catatonic_mode(struct autofs_sb_info *sbi)
+{
+ struct autofs_wait_queue *wq, *nwq;
+
+ DPRINTK("entering catatonic mode");
+
+ sbi->catatonic = 1;
+ wq = sbi->queues;
+ sbi->queues = NULL; /* Erase all wait queues */
+ while ( wq ) {
+ nwq = wq->next;
+ wq->status = -ENOENT; /* Magic is gone - report failure */
+ kfree(wq->name);
+ wq->name = NULL;
+ wake_up_interruptible(&wq->queue);
+ wq = nwq;
+ }
+ if (sbi->pipe) {
+ fput(sbi->pipe); /* Close the pipe */
+ sbi->pipe = NULL;
+ }
+
+ shrink_dcache_sb(sbi->sb);
+}
+
+static int autofs4_write(struct file *file, const void *addr, int bytes)
+{
+ unsigned long sigpipe, flags;
+ mm_segment_t fs;
+ const char *data = (const char *)addr;
+ ssize_t wr = 0;
+
+ /** WARNING: this is not safe for writing more than PIPE_BUF bytes! **/
+
+ sigpipe = sigismember(&current->pending.signal, SIGPIPE);
+
+ /* Save pointer to user space and point back to kernel space */
+ fs = get_fs();
+ set_fs(KERNEL_DS);
+
+ while (bytes &&
+ (wr = file->f_op->write(file,data,bytes,&file->f_pos)) > 0) {
+ data += wr;
+ bytes -= wr;
+ }
+
+ set_fs(fs);
+
+ /* Keep the currently executing process from receiving a
+ SIGPIPE unless it was already supposed to get one */
+ if (wr == -EPIPE && !sigpipe) {
+ spin_lock_irqsave(&current->sighand->siglock, flags);
+ sigdelset(&current->pending.signal, SIGPIPE);
+ recalc_sigpending();
+ spin_unlock_irqrestore(&current->sighand->siglock, flags);
+ }
+
+ return (bytes > 0);
+}
+
+static void autofs4_notify_daemon(struct autofs_sb_info *sbi,
+ struct autofs_wait_queue *wq,
+ int type)
+{
+ union autofs_packet_union pkt;
+ size_t pktsz;
+
+ DPRINTK("wait id = 0x%08lx, name = %.*s, type=%d",
+ wq->wait_queue_token, wq->len, wq->name, type);
+
+ memset(&pkt,0,sizeof pkt); /* For security reasons */
+
+ pkt.hdr.proto_version = sbi->version;
+ pkt.hdr.type = type;
+ if (type == autofs_ptype_missing) {
+ struct autofs_packet_missing *mp = &pkt.missing;
+
+ pktsz = sizeof(*mp);
+
+ mp->wait_queue_token = wq->wait_queue_token;
+ mp->len = wq->len;
+ memcpy(mp->name, wq->name, wq->len);
+ mp->name[wq->len] = '\0';
+ } else if (type == autofs_ptype_expire_multi) {
+ struct autofs_packet_expire_multi *ep = &pkt.expire_multi;
+
+ pktsz = sizeof(*ep);
+
+ ep->wait_queue_token = wq->wait_queue_token;
+ ep->len = wq->len;
+ memcpy(ep->name, wq->name, wq->len);
+ ep->name[wq->len] = '\0';
+ } else {
+ printk("autofs4_notify_daemon: bad type %d!\n", type);
+ return;
+ }
+
+ if (autofs4_write(sbi->pipe, &pkt, pktsz))
+ autofs4_catatonic_mode(sbi);
+}
+
+static int autofs4_getpath(struct autofs_sb_info *sbi,
+ struct dentry *dentry, char **name)
+{
+ struct dentry *root = sbi->sb->s_root;
+ struct dentry *tmp;
+ char *buf = *name;
+ char *p;
+ int len = 0;
+
+ spin_lock(&dcache_lock);
+ for (tmp = dentry ; tmp != root ; tmp = tmp->d_parent)
+ len += tmp->d_name.len + 1;
+
+ if (--len > NAME_MAX) {
+ spin_unlock(&dcache_lock);
+ return 0;
+ }
+
+ *(buf + len) = '\0';
+ p = buf + len - dentry->d_name.len;
+ strncpy(p, dentry->d_name.name, dentry->d_name.len);
+
+ for (tmp = dentry->d_parent; tmp != root ; tmp = tmp->d_parent) {
+ *(--p) = '/';
+ p -= tmp->d_name.len;
+ strncpy(p, tmp->d_name.name, tmp->d_name.len);
+ }
+ spin_unlock(&dcache_lock);
+
+ return len;
+}
+
+int autofs4_wait(struct autofs_sb_info *sbi, struct dentry *dentry,
+ enum autofs_notify notify)
+{
+ struct autofs_wait_queue *wq;
+ char *name;
+ int len, status;
+
+ /* In catatonic mode, we don't wait for nobody */
+ if ( sbi->catatonic )
+ return -ENOENT;
+
+ name = kmalloc(NAME_MAX + 1, GFP_KERNEL);
+ if (!name)
+ return -ENOMEM;
+
+ len = autofs4_getpath(sbi, dentry, &name);
+ if (!len) {
+ kfree(name);
+ return -ENOENT;
+ }
+
+ if (down_interruptible(&sbi->wq_sem)) {
+ kfree(name);
+ return -EINTR;
+ }
+
+ for (wq = sbi->queues ; wq ; wq = wq->next) {
+ if (wq->hash == dentry->d_name.hash &&
+ wq->len == len &&
+ wq->name && !memcmp(wq->name, name, len))
+ break;
+ }
+
+ if ( !wq ) {
+ /* Create a new wait queue */
+ wq = kmalloc(sizeof(struct autofs_wait_queue),GFP_KERNEL);
+ if ( !wq ) {
+ kfree(name);
+ up(&sbi->wq_sem);
+ return -ENOMEM;
+ }
+
+ wq->wait_queue_token = autofs4_next_wait_queue;
+ if (++autofs4_next_wait_queue == 0)
+ autofs4_next_wait_queue = 1;
+ wq->next = sbi->queues;
+ sbi->queues = wq;
+ init_waitqueue_head(&wq->queue);
+ wq->hash = dentry->d_name.hash;
+ wq->name = name;
+ wq->len = len;
+ wq->status = -EINTR; /* Status return if interrupted */
+ atomic_set(&wq->wait_ctr, 2);
+ up(&sbi->wq_sem);
+
+ DPRINTK("new wait id = 0x%08lx, name = %.*s, nfy=%d",
+ (unsigned long) wq->wait_queue_token, wq->len, wq->name, notify);
+ /* autofs4_notify_daemon() may block */
+ if (notify != NFY_NONE) {
+ autofs4_notify_daemon(sbi,wq,
+ notify == NFY_MOUNT ?
+ autofs_ptype_missing :
+ autofs_ptype_expire_multi);
+ }
+ } else {
+ atomic_inc(&wq->wait_ctr);
+ up(&sbi->wq_sem);
+ kfree(name);
+ DPRINTK("existing wait id = 0x%08lx, name = %.*s, nfy=%d",
+ (unsigned long) wq->wait_queue_token, wq->len, wq->name, notify);
+ }
+
+ /* wq->name is NULL if and only if the lock is already released */
+
+ if ( sbi->catatonic ) {
+ /* We might have slept, so check again for catatonic mode */
+ wq->status = -ENOENT;
+ if ( wq->name ) {
+ kfree(wq->name);
+ wq->name = NULL;
+ }
+ }
+
+ if ( wq->name ) {
+ /* Block all but "shutdown" signals while waiting */
+ sigset_t oldset;
+ unsigned long irqflags;
+
+ spin_lock_irqsave(&current->sighand->siglock, irqflags);
+ oldset = current->blocked;
+ siginitsetinv(&current->blocked, SHUTDOWN_SIGS & ~oldset.sig[0]);
+ recalc_sigpending();
+ spin_unlock_irqrestore(&current->sighand->siglock, irqflags);
+
+ wait_event_interruptible(wq->queue, wq->name == NULL);
+
+ spin_lock_irqsave(&current->sighand->siglock, irqflags);
+ current->blocked = oldset;
+ recalc_sigpending();
+ spin_unlock_irqrestore(&current->sighand->siglock, irqflags);
+ } else {
+ DPRINTK("skipped sleeping");
+ }
+
+ status = wq->status;
+
+ /* Are we the last process to need status? */
+ if (atomic_dec_and_test(&wq->wait_ctr))
+ kfree(wq);
+
+ return status;
+}
+
+
+int autofs4_wait_release(struct autofs_sb_info *sbi, autofs_wqt_t wait_queue_token, int status)
+{
+ struct autofs_wait_queue *wq, **wql;
+
+ down(&sbi->wq_sem);
+ for ( wql = &sbi->queues ; (wq = *wql) != 0 ; wql = &wq->next ) {
+ if ( wq->wait_queue_token == wait_queue_token )
+ break;
+ }
+
+ if ( !wq ) {
+ up(&sbi->wq_sem);
+ return -EINVAL;
+ }
+
+ *wql = wq->next; /* Unlink from chain */
+ up(&sbi->wq_sem);
+ kfree(wq->name);
+ wq->name = NULL; /* Do not wait on this queue */
+
+ wq->status = status;
+
+ if (atomic_dec_and_test(&wq->wait_ctr)) /* Is anyone still waiting for this guy? */
+ kfree(wq);
+ else
+ wake_up_interruptible(&wq->queue);
+
+ return 0;
+}
+