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-rw-r--r--fs/autofs/Makefile7
-rw-r--r--fs/autofs/autofs_i.h164
-rw-r--r--fs/autofs/dirhash.c249
-rw-r--r--fs/autofs/init.c52
-rw-r--r--fs/autofs/inode.c250
-rw-r--r--fs/autofs/root.c564
-rw-r--r--fs/autofs/symlink.c25
-rw-r--r--fs/autofs/waitq.c206
8 files changed, 1517 insertions, 0 deletions
diff --git a/fs/autofs/Makefile b/fs/autofs/Makefile
new file mode 100644
index 000000000000..453a60f46d05
--- /dev/null
+++ b/fs/autofs/Makefile
@@ -0,0 +1,7 @@
+#
+# Makefile for the linux autofs-filesystem routines.
+#
+
+obj-$(CONFIG_AUTOFS_FS) += autofs.o
+
+autofs-objs := dirhash.o init.o inode.o root.o symlink.o waitq.o
diff --git a/fs/autofs/autofs_i.h b/fs/autofs/autofs_i.h
new file mode 100644
index 000000000000..6171431272dc
--- /dev/null
+++ b/fs/autofs/autofs_i.h
@@ -0,0 +1,164 @@
+/* -*- linux-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_fs.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/dcache.h>
+#include <linux/namei.h>
+#include <linux/mount.h>
+#include <linux/sched.h>
+
+#include <asm/current.h>
+#include <asm/uaccess.h>
+
+#ifdef DEBUG
+#define DPRINTK(D) (printk D)
+#else
+#define DPRINTK(D) ((void)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 */
+
+/* Structures associated with the root directory hash table */
+
+#define AUTOFS_HASH_SIZE 67
+
+struct autofs_dir_ent {
+ int hash;
+ char *name;
+ int len;
+ ino_t ino;
+ struct dentry *dentry;
+ /* Linked list of entries */
+ struct autofs_dir_ent *next;
+ struct autofs_dir_ent **back;
+ /* The following entries are for the expiry system */
+ unsigned long last_usage;
+ struct list_head exp;
+};
+
+struct autofs_dirhash {
+ struct autofs_dir_ent *h[AUTOFS_HASH_SIZE];
+ struct list_head expiry_head;
+};
+
+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;
+ int wait_ctr;
+};
+
+struct autofs_symlink {
+ char *data;
+ int len;
+ time_t mtime;
+};
+
+#define AUTOFS_MAX_SYMLINKS 256
+
+#define AUTOFS_ROOT_INO 1
+#define AUTOFS_FIRST_SYMLINK 2
+#define AUTOFS_FIRST_DIR_INO (AUTOFS_FIRST_SYMLINK+AUTOFS_MAX_SYMLINKS)
+
+#define AUTOFS_SYMLINK_BITMAP_LEN \
+ ((AUTOFS_MAX_SYMLINKS+((sizeof(long)*1)-1))/(sizeof(long)*8))
+
+#define AUTOFS_SBI_MAGIC 0x6d4a556d
+
+struct autofs_sb_info {
+ u32 magic;
+ struct file *pipe;
+ pid_t oz_pgrp;
+ int catatonic;
+ unsigned long exp_timeout;
+ ino_t next_dir_ino;
+ struct autofs_wait_queue *queues; /* Wait queue pointer */
+ struct autofs_dirhash dirhash; /* Root directory hash */
+ struct autofs_symlink symlink[AUTOFS_MAX_SYMLINKS];
+ unsigned long symlink_bitmap[AUTOFS_SYMLINK_BITMAP_LEN];
+};
+
+static inline struct autofs_sb_info *autofs_sbi(struct super_block *sb)
+{
+ return (struct autofs_sb_info *)(sb->s_fs_info);
+}
+
+/* autofs_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 autofs_oz_mode(struct autofs_sb_info *sbi) {
+ return sbi->catatonic || process_group(current) == sbi->oz_pgrp;
+}
+
+/* Hash operations */
+
+void autofs_initialize_hash(struct autofs_dirhash *);
+struct autofs_dir_ent *autofs_hash_lookup(const struct autofs_dirhash *,struct qstr *);
+void autofs_hash_insert(struct autofs_dirhash *,struct autofs_dir_ent *);
+void autofs_hash_delete(struct autofs_dir_ent *);
+struct autofs_dir_ent *autofs_hash_enum(const struct autofs_dirhash *,off_t *,struct autofs_dir_ent *);
+void autofs_hash_dputall(struct autofs_dirhash *);
+void autofs_hash_nuke(struct autofs_dirhash *);
+
+/* Expiration-handling functions */
+
+void autofs_update_usage(struct autofs_dirhash *,struct autofs_dir_ent *);
+struct autofs_dir_ent *autofs_expire(struct super_block *,struct autofs_sb_info *, struct vfsmount *mnt);
+
+/* Operations structures */
+
+extern struct inode_operations autofs_root_inode_operations;
+extern struct inode_operations autofs_symlink_inode_operations;
+extern struct file_operations autofs_root_operations;
+
+/* Initializing function */
+
+int autofs_fill_super(struct super_block *, void *, int);
+
+/* Queue management functions */
+
+int autofs_wait(struct autofs_sb_info *,struct qstr *);
+int autofs_wait_release(struct autofs_sb_info *,autofs_wqt_t,int);
+void autofs_catatonic_mode(struct autofs_sb_info *);
+
+#ifdef DEBUG
+void autofs_say(const char *name, int len);
+#else
+#define autofs_say(n,l) ((void)0)
+#endif
diff --git a/fs/autofs/dirhash.c b/fs/autofs/dirhash.c
new file mode 100644
index 000000000000..448143fd0796
--- /dev/null
+++ b/fs/autofs/dirhash.c
@@ -0,0 +1,249 @@
+/* -*- linux-c -*- --------------------------------------------------------- *
+ *
+ * linux/fs/autofs/dirhash.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"
+
+/* Functions for maintenance of expiry queue */
+
+static void autofs_init_usage(struct autofs_dirhash *dh,
+ struct autofs_dir_ent *ent)
+{
+ list_add_tail(&ent->exp, &dh->expiry_head);
+ ent->last_usage = jiffies;
+}
+
+static void autofs_delete_usage(struct autofs_dir_ent *ent)
+{
+ list_del(&ent->exp);
+}
+
+void autofs_update_usage(struct autofs_dirhash *dh,
+ struct autofs_dir_ent *ent)
+{
+ autofs_delete_usage(ent); /* Unlink from current position */
+ autofs_init_usage(dh,ent); /* Relink at queue tail */
+}
+
+struct autofs_dir_ent *autofs_expire(struct super_block *sb,
+ struct autofs_sb_info *sbi,
+ struct vfsmount *mnt)
+{
+ struct autofs_dirhash *dh = &sbi->dirhash;
+ struct autofs_dir_ent *ent;
+ struct dentry *dentry;
+ unsigned long timeout = sbi->exp_timeout;
+
+ while (1) {
+ if ( list_empty(&dh->expiry_head) || sbi->catatonic )
+ return NULL; /* No entries */
+ /* We keep the list sorted by last_usage and want old stuff */
+ ent = list_entry(dh->expiry_head.next, struct autofs_dir_ent, exp);
+ if (jiffies - ent->last_usage < timeout)
+ break;
+ /* Move to end of list in case expiry isn't desirable */
+ autofs_update_usage(dh, ent);
+
+ /* Check to see that entry is expirable */
+ if ( ent->ino < AUTOFS_FIRST_DIR_INO )
+ return ent; /* Symlinks are always expirable */
+
+ /* Get the dentry for the autofs subdirectory */
+ dentry = ent->dentry;
+
+ if ( !dentry ) {
+ /* Should only happen in catatonic mode */
+ printk("autofs: dentry == NULL but inode range is directory, entry %s\n", ent->name);
+ autofs_delete_usage(ent);
+ continue;
+ }
+
+ if ( !dentry->d_inode ) {
+ dput(dentry);
+ printk("autofs: negative dentry on expiry queue: %s\n",
+ ent->name);
+ autofs_delete_usage(ent);
+ continue;
+ }
+
+ /* Make sure entry is mounted and unused; note that dentry will
+ point to the mounted-on-top root. */
+ if (!S_ISDIR(dentry->d_inode->i_mode)||!d_mountpoint(dentry)) {
+ DPRINTK(("autofs: not expirable (not a mounted directory): %s\n", ent->name));
+ continue;
+ }
+ mntget(mnt);
+ dget(dentry);
+ if (!follow_down(&mnt, &dentry)) {
+ dput(dentry);
+ mntput(mnt);
+ DPRINTK(("autofs: not expirable (not a mounted directory): %s\n", ent->name));
+ continue;
+ }
+ while (d_mountpoint(dentry) && follow_down(&mnt, &dentry))
+ ;
+ dput(dentry);
+
+ if ( may_umount(mnt) == 0 ) {
+ mntput(mnt);
+ DPRINTK(("autofs: signaling expire on %s\n", ent->name));
+ return ent; /* Expirable! */
+ }
+ DPRINTK(("autofs: didn't expire due to may_umount: %s\n", ent->name));
+ mntput(mnt);
+ }
+ return NULL; /* No expirable entries */
+}
+
+void autofs_initialize_hash(struct autofs_dirhash *dh) {
+ memset(&dh->h, 0, AUTOFS_HASH_SIZE*sizeof(struct autofs_dir_ent *));
+ INIT_LIST_HEAD(&dh->expiry_head);
+}
+
+struct autofs_dir_ent *autofs_hash_lookup(const struct autofs_dirhash *dh, struct qstr *name)
+{
+ struct autofs_dir_ent *dhn;
+
+ DPRINTK(("autofs_hash_lookup: hash = 0x%08x, name = ", name->hash));
+ autofs_say(name->name,name->len);
+
+ for ( dhn = dh->h[(unsigned) name->hash % AUTOFS_HASH_SIZE] ; dhn ; dhn = dhn->next ) {
+ if ( name->hash == dhn->hash &&
+ name->len == dhn->len &&
+ !memcmp(name->name, dhn->name, name->len) )
+ break;
+ }
+
+ return dhn;
+}
+
+void autofs_hash_insert(struct autofs_dirhash *dh, struct autofs_dir_ent *ent)
+{
+ struct autofs_dir_ent **dhnp;
+
+ DPRINTK(("autofs_hash_insert: hash = 0x%08x, name = ", ent->hash));
+ autofs_say(ent->name,ent->len);
+
+ autofs_init_usage(dh,ent);
+ if (ent->dentry)
+ dget(ent->dentry);
+
+ dhnp = &dh->h[(unsigned) ent->hash % AUTOFS_HASH_SIZE];
+ ent->next = *dhnp;
+ ent->back = dhnp;
+ *dhnp = ent;
+ if ( ent->next )
+ ent->next->back = &(ent->next);
+}
+
+void autofs_hash_delete(struct autofs_dir_ent *ent)
+{
+ *(ent->back) = ent->next;
+ if ( ent->next )
+ ent->next->back = ent->back;
+
+ autofs_delete_usage(ent);
+
+ if ( ent->dentry )
+ dput(ent->dentry);
+ kfree(ent->name);
+ kfree(ent);
+}
+
+/*
+ * Used by readdir(). We must validate "ptr", so we can't simply make it
+ * a pointer. Values below 0xffff are reserved; calling with any value
+ * <= 0x10000 will return the first entry found.
+ *
+ * "last" can be NULL or the value returned by the last search *if* we
+ * want the next sequential entry.
+ */
+struct autofs_dir_ent *autofs_hash_enum(const struct autofs_dirhash *dh,
+ off_t *ptr, struct autofs_dir_ent *last)
+{
+ int bucket, ecount, i;
+ struct autofs_dir_ent *ent;
+
+ bucket = (*ptr >> 16) - 1;
+ ecount = *ptr & 0xffff;
+
+ if ( bucket < 0 ) {
+ bucket = ecount = 0;
+ }
+
+ DPRINTK(("autofs_hash_enum: bucket %d, entry %d\n", bucket, ecount));
+
+ ent = last ? last->next : NULL;
+
+ if ( ent ) {
+ ecount++;
+ } else {
+ while ( bucket < AUTOFS_HASH_SIZE ) {
+ ent = dh->h[bucket];
+ for ( i = ecount ; ent && i ; i-- )
+ ent = ent->next;
+
+ if (ent) {
+ ecount++; /* Point to *next* entry */
+ break;
+ }
+
+ bucket++; ecount = 0;
+ }
+ }
+
+#ifdef DEBUG
+ if ( !ent )
+ printk("autofs_hash_enum: nothing found\n");
+ else {
+ printk("autofs_hash_enum: found hash %08x, name", ent->hash);
+ autofs_say(ent->name,ent->len);
+ }
+#endif
+
+ *ptr = ((bucket+1) << 16) + ecount;
+ return ent;
+}
+
+/* Iterate over all the ents, and remove all dentry pointers. Used on
+ entering catatonic mode, in order to make the filesystem unmountable. */
+void autofs_hash_dputall(struct autofs_dirhash *dh)
+{
+ int i;
+ struct autofs_dir_ent *ent;
+
+ for ( i = 0 ; i < AUTOFS_HASH_SIZE ; i++ ) {
+ for ( ent = dh->h[i] ; ent ; ent = ent->next ) {
+ if ( ent->dentry ) {
+ dput(ent->dentry);
+ ent->dentry = NULL;
+ }
+ }
+ }
+}
+
+/* Delete everything. This is used on filesystem destruction, so we
+ make no attempt to keep the pointers valid */
+void autofs_hash_nuke(struct autofs_dirhash *dh)
+{
+ int i;
+ struct autofs_dir_ent *ent, *nent;
+
+ for ( i = 0 ; i < AUTOFS_HASH_SIZE ; i++ ) {
+ for ( ent = dh->h[i] ; ent ; ent = nent ) {
+ nent = ent->next;
+ if ( ent->dentry )
+ dput(ent->dentry);
+ kfree(ent->name);
+ kfree(ent);
+ }
+ }
+}
diff --git a/fs/autofs/init.c b/fs/autofs/init.c
new file mode 100644
index 000000000000..b977ece69f0c
--- /dev/null
+++ b/fs/autofs/init.c
@@ -0,0 +1,52 @@
+/* -*- linux-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, autofs_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_autofs_fs(void)
+{
+ return register_filesystem(&autofs_fs_type);
+}
+
+static void __exit exit_autofs_fs(void)
+{
+ unregister_filesystem(&autofs_fs_type);
+}
+
+module_init(init_autofs_fs);
+module_exit(exit_autofs_fs);
+
+#ifdef DEBUG
+void autofs_say(const char *name, int len)
+{
+ printk("(%d: ", len);
+ while ( len-- )
+ printk("%c", *name++);
+ printk(")\n");
+}
+#endif
+MODULE_LICENSE("GPL");
diff --git a/fs/autofs/inode.c b/fs/autofs/inode.c
new file mode 100644
index 000000000000..4888c1fabbf7
--- /dev/null
+++ b/fs/autofs/inode.c
@@ -0,0 +1,250 @@
+/* -*- linux-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/mm.h>
+#include <linux/slab.h>
+#include <linux/file.h>
+#include <linux/parser.h>
+#include <linux/bitops.h>
+#include "autofs_i.h"
+#include <linux/module.h>
+
+static void autofs_put_super(struct super_block *sb)
+{
+ struct autofs_sb_info *sbi = autofs_sbi(sb);
+ unsigned int n;
+
+ if ( !sbi->catatonic )
+ autofs_catatonic_mode(sbi); /* Free wait queues, close pipe */
+
+ autofs_hash_nuke(&sbi->dirhash);
+ for ( n = 0 ; n < AUTOFS_MAX_SYMLINKS ; n++ ) {
+ if ( test_bit(n, sbi->symlink_bitmap) )
+ kfree(sbi->symlink[n].data);
+ }
+
+ kfree(sb->s_fs_info);
+
+ DPRINTK(("autofs: shutting down\n"));
+}
+
+static void autofs_read_inode(struct inode *inode);
+
+static struct super_operations autofs_sops = {
+ .read_inode = autofs_read_inode,
+ .put_super = autofs_put_super,
+ .statfs = simple_statfs,
+};
+
+enum {Opt_err, Opt_fd, Opt_uid, Opt_gid, Opt_pgrp, Opt_minproto, Opt_maxproto};
+
+static match_table_t autofs_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 = *maxproto = AUTOFS_PROTO_VERSION;
+
+ *pipefd = -1;
+
+ if (!options)
+ return 1;
+
+ while ((p = strsep(&options, ",")) != NULL) {
+ int token;
+ if (!*p)
+ continue;
+
+ token = match_token(p, autofs_tokens, args);
+ switch (token) {
+ case Opt_fd:
+ if (match_int(&args[0], &option))
+ return 1;
+ *pipefd = option;
+ break;
+ case Opt_uid:
+ if (match_int(&args[0], &option))
+ return 1;
+ *uid = option;
+ break;
+ case Opt_gid:
+ if (match_int(&args[0], &option))
+ return 1;
+ *gid = option;
+ break;
+ case Opt_pgrp:
+ if (match_int(&args[0], &option))
+ return 1;
+ *pgrp = option;
+ break;
+ case Opt_minproto:
+ if (match_int(&args[0], &option))
+ return 1;
+ *minproto = option;
+ break;
+ case Opt_maxproto:
+ if (match_int(&args[0], &option))
+ return 1;
+ *maxproto = option;
+ break;
+ default:
+ return 1;
+ }
+ }
+ return (*pipefd < 0);
+}
+
+int autofs_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;
+ int minproto, maxproto;
+
+ sbi = kmalloc(sizeof(*sbi), GFP_KERNEL);
+ if ( !sbi )
+ goto fail_unlock;
+ memset(sbi, 0, sizeof(*sbi));
+ DPRINTK(("autofs: starting up, sbi = %p\n",sbi));
+
+ s->s_fs_info = sbi;
+ sbi->magic = AUTOFS_SBI_MAGIC;
+ sbi->catatonic = 0;
+ sbi->exp_timeout = 0;
+ sbi->oz_pgrp = process_group(current);
+ autofs_initialize_hash(&sbi->dirhash);
+ sbi->queues = NULL;
+ memset(sbi->symlink_bitmap, 0, sizeof(long)*AUTOFS_SYMLINK_BITMAP_LEN);
+ sbi->next_dir_ino = AUTOFS_FIRST_DIR_INO;
+ s->s_blocksize = 1024;
+ s->s_blocksize_bits = 10;
+ s->s_magic = AUTOFS_SUPER_MAGIC;
+ s->s_op = &autofs_sops;
+ s->s_time_gran = 1;
+
+ root_inode = iget(s, AUTOFS_ROOT_INO);
+ root = d_alloc_root(root_inode);
+ pipe = NULL;
+
+ if (!root)
+ goto fail_iput;
+
+ /* Can this call block? - WTF cares? s is locked. */
+ 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 ( minproto > AUTOFS_PROTO_VERSION ||
+ maxproto < AUTOFS_PROTO_VERSION ) {
+ printk("autofs: kernel does not match daemon version\n");
+ goto fail_dput;
+ }
+
+ DPRINTK(("autofs: pipe fd = %d, pgrp = %u\n", 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;
+
+fail_fput:
+ printk("autofs: pipe file descriptor does not contain proper ops\n");
+ fput(pipe);
+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;
+}
+
+static void autofs_read_inode(struct inode *inode)
+{
+ ino_t ino = inode->i_ino;
+ unsigned int n;
+ struct autofs_sb_info *sbi = autofs_sbi(inode->i_sb);
+
+ /* Initialize to the default case (stub directory) */
+
+ inode->i_op = &simple_dir_inode_operations;
+ inode->i_fop = &simple_dir_operations;
+ inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO;
+ inode->i_nlink = 2;
+ inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
+ inode->i_blocks = 0;
+ inode->i_blksize = 1024;
+
+ if ( ino == AUTOFS_ROOT_INO ) {
+ inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO | S_IWUSR;
+ inode->i_op = &autofs_root_inode_operations;
+ inode->i_fop = &autofs_root_operations;
+ inode->i_uid = inode->i_gid = 0; /* Changed in read_super */
+ return;
+ }
+
+ inode->i_uid = inode->i_sb->s_root->d_inode->i_uid;
+ inode->i_gid = inode->i_sb->s_root->d_inode->i_gid;
+
+ if ( ino >= AUTOFS_FIRST_SYMLINK && ino < AUTOFS_FIRST_DIR_INO ) {
+ /* Symlink inode - should be in symlink list */
+ struct autofs_symlink *sl;
+
+ n = ino - AUTOFS_FIRST_SYMLINK;
+ if ( n >= AUTOFS_MAX_SYMLINKS || !test_bit(n,sbi->symlink_bitmap)) {
+ printk("autofs: Looking for bad symlink inode %u\n", (unsigned int) ino);
+ return;
+ }
+
+ inode->i_op = &autofs_symlink_inode_operations;
+ sl = &sbi->symlink[n];
+ inode->u.generic_ip = sl;
+ inode->i_mode = S_IFLNK | S_IRWXUGO;
+ inode->i_mtime.tv_sec = inode->i_ctime.tv_sec = sl->mtime;
+ inode->i_mtime.tv_nsec = inode->i_ctime.tv_nsec = 0;
+ inode->i_size = sl->len;
+ inode->i_nlink = 1;
+ }
+}
diff --git a/fs/autofs/root.c b/fs/autofs/root.c
new file mode 100644
index 000000000000..a1ab1c0ed215
--- /dev/null
+++ b/fs/autofs/root.c
@@ -0,0 +1,564 @@
+/* -*- linux-c -*- --------------------------------------------------------- *
+ *
+ * linux/fs/autofs/root.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/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 autofs_root_readdir(struct file *,void *,filldir_t);
+static struct dentry *autofs_root_lookup(struct inode *,struct dentry *, struct nameidata *);
+static int autofs_root_symlink(struct inode *,struct dentry *,const char *);
+static int autofs_root_unlink(struct inode *,struct dentry *);
+static int autofs_root_rmdir(struct inode *,struct dentry *);
+static int autofs_root_mkdir(struct inode *,struct dentry *,int);
+static int autofs_root_ioctl(struct inode *, struct file *,unsigned int,unsigned long);
+
+struct file_operations autofs_root_operations = {
+ .read = generic_read_dir,
+ .readdir = autofs_root_readdir,
+ .ioctl = autofs_root_ioctl,
+};
+
+struct inode_operations autofs_root_inode_operations = {
+ .lookup = autofs_root_lookup,
+ .unlink = autofs_root_unlink,
+ .symlink = autofs_root_symlink,
+ .mkdir = autofs_root_mkdir,
+ .rmdir = autofs_root_rmdir,
+};
+
+static int autofs_root_readdir(struct file *filp, void *dirent, filldir_t filldir)
+{
+ struct autofs_dir_ent *ent = NULL;
+ struct autofs_dirhash *dirhash;
+ struct autofs_sb_info *sbi;
+ struct inode * inode = filp->f_dentry->d_inode;
+ off_t onr, nr;
+
+ lock_kernel();
+
+ sbi = autofs_sbi(inode->i_sb);
+ dirhash = &sbi->dirhash;
+ nr = filp->f_pos;
+
+ switch(nr)
+ {
+ case 0:
+ if (filldir(dirent, ".", 1, nr, inode->i_ino, DT_DIR) < 0)
+ goto out;
+ filp->f_pos = ++nr;
+ /* fall through */
+ case 1:
+ if (filldir(dirent, "..", 2, nr, inode->i_ino, DT_DIR) < 0)
+ goto out;
+ filp->f_pos = ++nr;
+ /* fall through */
+ default:
+ while ( onr = nr, ent = autofs_hash_enum(dirhash,&nr,ent) ) {
+ if ( !ent->dentry || d_mountpoint(ent->dentry) ) {
+ if (filldir(dirent,ent->name,ent->len,onr,ent->ino,DT_UNKNOWN) < 0)
+ goto out;
+ filp->f_pos = nr;
+ }
+ }
+ break;
+ }
+
+out:
+ unlock_kernel();
+ return 0;
+}
+
+static int try_to_fill_dentry(struct dentry *dentry, struct super_block *sb, struct autofs_sb_info *sbi)
+{
+ struct inode * inode;
+ struct autofs_dir_ent *ent;
+ int status = 0;
+
+ if ( !(ent = autofs_hash_lookup(&sbi->dirhash, &dentry->d_name)) ) {
+ do {
+ if ( status && dentry->d_inode ) {
+ if ( status != -ENOENT )
+ printk("autofs warning: lookup failure on positive dentry, status = %d, name = %s\n", status, dentry->d_name.name);
+ 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;
+ dentry->d_flags &= ~DCACHE_AUTOFS_PENDING;
+ return 1;
+ } else if (status) {
+ /* Return a negative dentry, but leave it "pending" */
+ return 1;
+ }
+ status = autofs_wait(sbi, &dentry->d_name);
+ } while (!(ent = autofs_hash_lookup(&sbi->dirhash, &dentry->d_name)) );
+ }
+
+ /* Abuse this field as a pointer to the directory entry, used to
+ find the expire list pointers */
+ dentry->d_time = (unsigned long) ent;
+
+ if (!dentry->d_inode) {
+ inode = iget(sb, ent->ino);
+ if (!inode) {
+ /* Failed, but leave pending for next time */
+ return 1;
+ }
+ dentry->d_inode = inode;
+ }
+
+ /* If this is a directory that isn't a mount point, bitch at the
+ daemon and fix it in user space */
+ if ( S_ISDIR(dentry->d_inode->i_mode) && !d_mountpoint(dentry) ) {
+ return !autofs_wait(sbi, &dentry->d_name);
+ }
+
+ /* We don't update the usages for the autofs daemon itself, this
+ is necessary for recursive autofs mounts */
+ if ( !autofs_oz_mode(sbi) ) {
+ autofs_update_usage(&sbi->dirhash,ent);
+ }
+
+ dentry->d_flags &= ~DCACHE_AUTOFS_PENDING;
+ 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 autofs_revalidate(struct dentry * dentry, struct nameidata *nd)
+{
+ struct inode * dir;
+ struct autofs_sb_info *sbi;
+ struct autofs_dir_ent *ent;
+ int res;
+
+ lock_kernel();
+ dir = dentry->d_parent->d_inode;
+ sbi = autofs_sbi(dir->i_sb);
+
+ /* Pending dentry */
+ if ( dentry->d_flags & DCACHE_AUTOFS_PENDING ) {
+ if (autofs_oz_mode(sbi))
+ res = 1;
+ else
+ res = try_to_fill_dentry(dentry, dir->i_sb, sbi);
+ unlock_kernel();
+ return res;
+ }
+
+ /* Negative dentry.. invalidate if "old" */
+ if (!dentry->d_inode) {
+ unlock_kernel();
+ return (dentry->d_time - jiffies <= AUTOFS_NEGATIVE_TIMEOUT);
+ }
+
+ /* Check for a non-mountpoint directory */
+ if ( S_ISDIR(dentry->d_inode->i_mode) && !d_mountpoint(dentry) ) {
+ if (autofs_oz_mode(sbi))
+ res = 1;
+ else
+ res = try_to_fill_dentry(dentry, dir->i_sb, sbi);
+ unlock_kernel();
+ return res;
+ }
+
+ /* Update the usage list */
+ if ( !autofs_oz_mode(sbi) ) {
+ ent = (struct autofs_dir_ent *) dentry->d_time;
+ if ( ent )
+ autofs_update_usage(&sbi->dirhash,ent);
+ }
+ unlock_kernel();
+ return 1;
+}
+
+static struct dentry_operations autofs_dentry_operations = {
+ .d_revalidate = autofs_revalidate,
+};
+
+static struct dentry *autofs_root_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd)
+{
+ struct autofs_sb_info *sbi;
+ int oz_mode;
+
+ DPRINTK(("autofs_root_lookup: name = "));
+ lock_kernel();
+ autofs_say(dentry->d_name.name,dentry->d_name.len);
+
+ if (dentry->d_name.len > NAME_MAX) {
+ unlock_kernel();
+ return ERR_PTR(-ENAMETOOLONG);/* File name too long to exist */
+ }
+
+ sbi = autofs_sbi(dir->i_sb);
+
+ oz_mode = autofs_oz_mode(sbi);
+ DPRINTK(("autofs_lookup: pid = %u, pgrp = %u, catatonic = %d, oz_mode = %d\n",
+ 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 = &autofs_dentry_operations;
+ dentry->d_flags |= DCACHE_AUTOFS_PENDING;
+ d_add(dentry, NULL);
+
+ up(&dir->i_sem);
+ autofs_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)) {
+ unlock_kernel();
+ return ERR_PTR(-ERESTARTNOINTR);
+ }
+ }
+ }
+ unlock_kernel();
+
+ /*
+ * 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 autofs_root_symlink(struct inode *dir, struct dentry *dentry, const char *symname)
+{
+ struct autofs_sb_info *sbi = autofs_sbi(dir->i_sb);
+ struct autofs_dirhash *dh = &sbi->dirhash;
+ struct autofs_dir_ent *ent;
+ unsigned int n;
+ int slsize;
+ struct autofs_symlink *sl;
+
+ DPRINTK(("autofs_root_symlink: %s <- ", symname));
+ autofs_say(dentry->d_name.name,dentry->d_name.len);
+
+ lock_kernel();
+ if ( !autofs_oz_mode(sbi) ) {
+ unlock_kernel();
+ return -EACCES;
+ }
+
+ if ( autofs_hash_lookup(dh, &dentry->d_name) ) {
+ unlock_kernel();
+ return -EEXIST;
+ }
+
+ n = find_first_zero_bit(sbi->symlink_bitmap,AUTOFS_MAX_SYMLINKS);
+ if ( n >= AUTOFS_MAX_SYMLINKS ) {
+ unlock_kernel();
+ return -ENOSPC;
+ }
+
+ set_bit(n,sbi->symlink_bitmap);
+ sl = &sbi->symlink[n];
+ sl->len = strlen(symname);
+ sl->data = kmalloc(slsize = sl->len+1, GFP_KERNEL);
+ if ( !sl->data ) {
+ clear_bit(n,sbi->symlink_bitmap);
+ unlock_kernel();
+ return -ENOSPC;
+ }
+
+ ent = kmalloc(sizeof(struct autofs_dir_ent), GFP_KERNEL);
+ if ( !ent ) {
+ kfree(sl->data);
+ clear_bit(n,sbi->symlink_bitmap);
+ unlock_kernel();
+ return -ENOSPC;
+ }
+
+ ent->name = kmalloc(dentry->d_name.len+1, GFP_KERNEL);
+ if ( !ent->name ) {
+ kfree(sl->data);
+ kfree(ent);
+ clear_bit(n,sbi->symlink_bitmap);
+ unlock_kernel();
+ return -ENOSPC;
+ }
+
+ memcpy(sl->data,symname,slsize);
+ sl->mtime = get_seconds();
+
+ ent->ino = AUTOFS_FIRST_SYMLINK + n;
+ ent->hash = dentry->d_name.hash;
+ memcpy(ent->name, dentry->d_name.name, 1+(ent->len = dentry->d_name.len));
+ ent->dentry = NULL; /* We don't keep the dentry for symlinks */
+
+ autofs_hash_insert(dh,ent);
+ d_instantiate(dentry, iget(dir->i_sb,ent->ino));
+ unlock_kernel();
+ 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, which we
+ * obviously do not want (we're dropping the entry not because it
+ * doesn't exist, but because it has timed out).
+ *
+ * Also see autofs_root_rmdir()..
+ */
+static int autofs_root_unlink(struct inode *dir, struct dentry *dentry)
+{
+ struct autofs_sb_info *sbi = autofs_sbi(dir->i_sb);
+ struct autofs_dirhash *dh = &sbi->dirhash;
+ struct autofs_dir_ent *ent;
+ unsigned int n;
+
+ /* This allows root to remove symlinks */
+ lock_kernel();
+ if ( !autofs_oz_mode(sbi) && !capable(CAP_SYS_ADMIN) ) {
+ unlock_kernel();
+ return -EACCES;
+ }
+
+ ent = autofs_hash_lookup(dh, &dentry->d_name);
+ if ( !ent ) {
+ unlock_kernel();
+ return -ENOENT;
+ }
+
+ n = ent->ino - AUTOFS_FIRST_SYMLINK;
+ if ( n >= AUTOFS_MAX_SYMLINKS ) {
+ unlock_kernel();
+ return -EISDIR; /* It's a directory, dummy */
+ }
+ if ( !test_bit(n,sbi->symlink_bitmap) ) {
+ unlock_kernel();
+ return -EINVAL; /* Nonexistent symlink? Shouldn't happen */
+ }
+
+ dentry->d_time = (unsigned long)(struct autofs_dirhash *)NULL;
+ autofs_hash_delete(ent);
+ clear_bit(n,sbi->symlink_bitmap);
+ kfree(sbi->symlink[n].data);
+ d_drop(dentry);
+
+ unlock_kernel();
+ return 0;
+}
+
+static int autofs_root_rmdir(struct inode *dir, struct dentry *dentry)
+{
+ struct autofs_sb_info *sbi = autofs_sbi(dir->i_sb);
+ struct autofs_dirhash *dh = &sbi->dirhash;
+ struct autofs_dir_ent *ent;
+
+ lock_kernel();
+ if ( !autofs_oz_mode(sbi) ) {
+ unlock_kernel();
+ return -EACCES;
+ }
+
+ ent = autofs_hash_lookup(dh, &dentry->d_name);
+ if ( !ent ) {
+ unlock_kernel();
+ return -ENOENT;
+ }
+
+ if ( (unsigned int)ent->ino < AUTOFS_FIRST_DIR_INO ) {
+ unlock_kernel();
+ return -ENOTDIR; /* Not a directory */
+ }
+
+ if ( ent->dentry != dentry ) {
+ printk("autofs_rmdir: odentry != dentry for entry %s\n", dentry->d_name.name);
+ }
+
+ dentry->d_time = (unsigned long)(struct autofs_dir_ent *)NULL;
+ autofs_hash_delete(ent);
+ dir->i_nlink--;
+ d_drop(dentry);
+ unlock_kernel();
+
+ return 0;
+}
+
+static int autofs_root_mkdir(struct inode *dir, struct dentry *dentry, int mode)
+{
+ struct autofs_sb_info *sbi = autofs_sbi(dir->i_sb);
+ struct autofs_dirhash *dh = &sbi->dirhash;
+ struct autofs_dir_ent *ent;
+ ino_t ino;
+
+ lock_kernel();
+ if ( !autofs_oz_mode(sbi) ) {
+ unlock_kernel();
+ return -EACCES;
+ }
+
+ ent = autofs_hash_lookup(dh, &dentry->d_name);
+ if ( ent ) {
+ unlock_kernel();
+ return -EEXIST;
+ }
+
+ if ( sbi->next_dir_ino < AUTOFS_FIRST_DIR_INO ) {
+ printk("autofs: Out of inode numbers -- what the heck did you do??\n");
+ unlock_kernel();
+ return -ENOSPC;
+ }
+ ino = sbi->next_dir_ino++;
+
+ ent = kmalloc(sizeof(struct autofs_dir_ent), GFP_KERNEL);
+ if ( !ent ) {
+ unlock_kernel();
+ return -ENOSPC;
+ }
+
+ ent->name = kmalloc(dentry->d_name.len+1, GFP_KERNEL);
+ if ( !ent->name ) {
+ kfree(ent);
+ unlock_kernel();
+ return -ENOSPC;
+ }
+
+ ent->hash = dentry->d_name.hash;
+ memcpy(ent->name, dentry->d_name.name, 1+(ent->len = dentry->d_name.len));
+ ent->ino = ino;
+ ent->dentry = dentry;
+ autofs_hash_insert(dh,ent);
+
+ dir->i_nlink++;
+ d_instantiate(dentry, iget(dir->i_sb,ino));
+ unlock_kernel();
+
+ return 0;
+}
+
+/* Get/set timeout ioctl() operation */
+static inline int autofs_get_set_timeout(struct autofs_sb_info *sbi,
+ unsigned long __user *p)
+{
+ unsigned long ntimeout;
+
+ if (get_user(ntimeout, p) ||
+ put_user(sbi->exp_timeout / HZ, p))
+ return -EFAULT;
+
+ if ( ntimeout > ULONG_MAX/HZ )
+ sbi->exp_timeout = 0;
+ else
+ sbi->exp_timeout = ntimeout * HZ;
+
+ return 0;
+}
+
+/* Return protocol version */
+static inline int autofs_get_protover(int __user *p)
+{
+ return put_user(AUTOFS_PROTO_VERSION, p);
+}
+
+/* Perform an expiry operation */
+static inline int autofs_expire_run(struct super_block *sb,
+ struct autofs_sb_info *sbi,
+ struct vfsmount *mnt,
+ struct autofs_packet_expire __user *pkt_p)
+{
+ struct autofs_dir_ent *ent;
+ struct autofs_packet_expire pkt;
+
+ memset(&pkt,0,sizeof pkt);
+
+ pkt.hdr.proto_version = AUTOFS_PROTO_VERSION;
+ pkt.hdr.type = autofs_ptype_expire;
+
+ if ( !sbi->exp_timeout ||
+ !(ent = autofs_expire(sb,sbi,mnt)) )
+ return -EAGAIN;
+
+ pkt.len = ent->len;
+ memcpy(pkt.name, ent->name, pkt.len);
+ pkt.name[pkt.len] = '\0';
+
+ if ( copy_to_user(pkt_p, &pkt, sizeof(struct autofs_packet_expire)) )
+ return -EFAULT;
+
+ return 0;
+}
+
+/*
+ * ioctl()'s on the root directory is the chief method for the daemon to
+ * generate kernel reactions
+ */
+static int autofs_root_ioctl(struct inode *inode, struct file *filp,
+ unsigned int cmd, unsigned long arg)
+{
+ struct autofs_sb_info *sbi = autofs_sbi(inode->i_sb);
+ void __user *argp = (void __user *)arg;
+
+ DPRINTK(("autofs_ioctl: cmd = 0x%08x, arg = 0x%08lx, sbi = %p, pgrp = %u\n",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 ( !autofs_oz_mode(sbi) && !capable(CAP_SYS_ADMIN) )
+ return -EPERM;
+
+ switch(cmd) {
+ case AUTOFS_IOC_READY: /* Wait queue: go ahead and retry */
+ return autofs_wait_release(sbi,(autofs_wqt_t)arg,0);
+ case AUTOFS_IOC_FAIL: /* Wait queue: fail with ENOENT */
+ return autofs_wait_release(sbi,(autofs_wqt_t)arg,-ENOENT);
+ case AUTOFS_IOC_CATATONIC: /* Enter catatonic mode (daemon shutdown) */
+ autofs_catatonic_mode(sbi);
+ return 0;
+ case AUTOFS_IOC_PROTOVER: /* Get protocol version */
+ return autofs_get_protover(argp);
+ case AUTOFS_IOC_SETTIMEOUT:
+ return autofs_get_set_timeout(sbi, argp);
+ case AUTOFS_IOC_EXPIRE:
+ return autofs_expire_run(inode->i_sb, sbi, filp->f_vfsmnt,
+ argp);
+ default:
+ return -ENOSYS;
+ }
+}
diff --git a/fs/autofs/symlink.c b/fs/autofs/symlink.c
new file mode 100644
index 000000000000..f028396f1383
--- /dev/null
+++ b/fs/autofs/symlink.c
@@ -0,0 +1,25 @@
+/* -*- linux-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 autofs_follow_link(struct dentry *dentry, struct nameidata *nd)
+{
+ char *s=((struct autofs_symlink *)dentry->d_inode->u.generic_ip)->data;
+ nd_set_link(nd, s);
+ return 0;
+}
+
+struct inode_operations autofs_symlink_inode_operations = {
+ .readlink = generic_readlink,
+ .follow_link = autofs_follow_link
+};
diff --git a/fs/autofs/waitq.c b/fs/autofs/waitq.c
new file mode 100644
index 000000000000..1fcaa1568541
--- /dev/null
+++ b/fs/autofs/waitq.c
@@ -0,0 +1,206 @@
+/* -*- linux-c -*- --------------------------------------------------------- *
+ *
+ * linux/fs/autofs/waitq.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/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 autofs_next_wait_queue = 1;
+
+/* These are the signals we allow interrupting a pending mount */
+#define SHUTDOWN_SIGS (sigmask(SIGKILL) | sigmask(SIGINT) | sigmask(SIGQUIT))
+
+void autofs_catatonic_mode(struct autofs_sb_info *sbi)
+{
+ struct autofs_wait_queue *wq, *nwq;
+
+ DPRINTK(("autofs: entering catatonic mode\n"));
+
+ 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(&wq->queue);
+ wq = nwq;
+ }
+ fput(sbi->pipe); /* Close the pipe */
+ autofs_hash_dputall(&sbi->dirhash); /* Remove all dentry pointers */
+}
+
+static int autofs_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 autofs_notify_daemon(struct autofs_sb_info *sbi, struct autofs_wait_queue *wq)
+{
+ struct autofs_packet_missing pkt;
+
+ DPRINTK(("autofs_wait: wait id = 0x%08lx, name = ", wq->wait_queue_token));
+ autofs_say(wq->name,wq->len);
+
+ memset(&pkt,0,sizeof pkt); /* For security reasons */
+
+ pkt.hdr.proto_version = AUTOFS_PROTO_VERSION;
+ pkt.hdr.type = autofs_ptype_missing;
+ pkt.wait_queue_token = wq->wait_queue_token;
+ pkt.len = wq->len;
+ memcpy(pkt.name, wq->name, pkt.len);
+ pkt.name[pkt.len] = '\0';
+
+ if ( autofs_write(sbi->pipe,&pkt,sizeof(struct autofs_packet_missing)) )
+ autofs_catatonic_mode(sbi);
+}
+
+int autofs_wait(struct autofs_sb_info *sbi, struct qstr *name)
+{
+ struct autofs_wait_queue *wq;
+ int status;
+
+ /* In catatonic mode, we don't wait for nobody */
+ if ( sbi->catatonic )
+ return -ENOENT;
+
+ /* We shouldn't be able to get here, but just in case */
+ if ( name->len > NAME_MAX )
+ return -ENOENT;
+
+ for ( wq = sbi->queues ; wq ; wq = wq->next ) {
+ if ( wq->hash == name->hash &&
+ wq->len == name->len &&
+ wq->name && !memcmp(wq->name,name->name,name->len) )
+ break;
+ }
+
+ if ( !wq ) {
+ /* Create a new wait queue */
+ wq = kmalloc(sizeof(struct autofs_wait_queue),GFP_KERNEL);
+ if ( !wq )
+ return -ENOMEM;
+
+ wq->name = kmalloc(name->len,GFP_KERNEL);
+ if ( !wq->name ) {
+ kfree(wq);
+ return -ENOMEM;
+ }
+ wq->wait_queue_token = autofs_next_wait_queue++;
+ init_waitqueue_head(&wq->queue);
+ wq->hash = name->hash;
+ wq->len = name->len;
+ wq->status = -EINTR; /* Status return if interrupted */
+ memcpy(wq->name, name->name, name->len);
+ wq->next = sbi->queues;
+ sbi->queues = wq;
+
+ /* autofs_notify_daemon() may block */
+ wq->wait_ctr = 2;
+ autofs_notify_daemon(sbi,wq);
+ } else
+ wq->wait_ctr++;
+
+ /* 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 sigmask;
+
+ siginitsetinv(&sigmask, SHUTDOWN_SIGS);
+ sigprocmask(SIG_BLOCK, &sigmask, &sigmask);
+
+ interruptible_sleep_on(&wq->queue);
+
+ sigprocmask(SIG_SETMASK, &sigmask, NULL);
+ } else {
+ DPRINTK(("autofs_wait: skipped sleeping\n"));
+ }
+
+ status = wq->status;
+
+ if ( ! --wq->wait_ctr ) /* Are we the last process to need status? */
+ kfree(wq);
+
+ return status;
+}
+
+
+int autofs_wait_release(struct autofs_sb_info *sbi, autofs_wqt_t wait_queue_token, int status)
+{
+ struct autofs_wait_queue *wq, **wql;
+
+ for ( wql = &sbi->queues ; (wq = *wql) != 0 ; wql = &wq->next ) {
+ if ( wq->wait_queue_token == wait_queue_token )
+ break;
+ }
+ if ( !wq )
+ return -EINVAL;
+
+ *wql = wq->next; /* Unlink from chain */
+ kfree(wq->name);
+ wq->name = NULL; /* Do not wait on this queue */
+
+ wq->status = status;
+
+ if ( ! --wq->wait_ctr ) /* Is anyone still waiting for this guy? */
+ kfree(wq);
+ else
+ wake_up(&wq->queue);
+
+ return 0;
+}
+