*
* Copyright 1997-1998 Transmeta Corporation -- All Rights Reserved
* Copyright 1999-2000 Jeremy Fitzhardinge <jeremy@goop.org>
- * Copyright 2001-2003 Ian Kent <raven@themaw.net>
+ * Copyright 2001-2006 Ian Kent <raven@themaw.net>
*
* This file is part of the Linux kernel and is made available under
* the terms of the GNU General Public License, version 2, or at your
*
* ------------------------------------------------------------------------- */
+#include <linux/capability.h>
#include <linux/errno.h>
#include <linux/stat.h>
#include <linux/param.h>
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);
+static void *autofs4_follow_link(struct dentry *, struct nameidata *);
-struct file_operations autofs4_root_operations = {
+const struct file_operations autofs4_root_operations = {
.open = dcache_dir_open,
.release = dcache_dir_close,
.read = generic_read_dir,
.ioctl = autofs4_root_ioctl,
};
-struct file_operations autofs4_dir_operations = {
+const 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 = {
+struct inode_operations autofs4_indirect_root_inode_operations = {
.lookup = autofs4_lookup,
.unlink = autofs4_dir_unlink,
.symlink = autofs4_dir_symlink,
.rmdir = autofs4_dir_rmdir,
};
+struct inode_operations autofs4_direct_root_inode_operations = {
+ .lookup = autofs4_lookup,
+ .unlink = autofs4_dir_unlink,
+ .mkdir = autofs4_dir_mkdir,
+ .rmdir = autofs4_dir_rmdir,
+ .follow_link = autofs4_follow_link,
+};
+
struct inode_operations autofs4_dir_inode_operations = {
.lookup = autofs4_lookup,
.unlink = autofs4_dir_unlink,
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;
+ return dcache_readdir(file, dirent, filldir);
}
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);
+ struct dentry *cursor;
int status;
+ status = dcache_dir_open(inode, file);
+ if (status)
+ goto out;
+
+ cursor = file->private_data;
+ cursor->d_fsdata = NULL;
+
DPRINTK("file=%p dentry=%p %.*s",
file, dentry, dentry->d_name.len, dentry->d_name.name);
if (autofs4_ispending(dentry)) {
DPRINTK("dentry busy");
- return -EBUSY;
+ dcache_dir_close(inode, file);
+ status = -EBUSY;
+ goto out;
}
+ status = -ENOENT;
if (!d_mountpoint(dentry) && dentry->d_op && dentry->d_op->d_revalidate) {
struct nameidata nd;
- int empty;
+ int empty, ret;
/* In case there are stale directory dentrys from a failed mount */
spin_lock(&dcache_lock);
d_invalidate(dentry);
nd.flags = LOOKUP_DIRECTORY;
- status = (dentry->d_op->d_revalidate)(dentry, &nd);
+ ret = (dentry->d_op->d_revalidate)(dentry, &nd);
- if (!status)
- return -ENOENT;
+ if (!ret) {
+ dcache_dir_close(inode, file);
+ goto out;
+ }
}
if (d_mountpoint(dentry)) {
struct vfsmount *fp_mnt = mntget(mnt);
struct dentry *fp_dentry = dget(dentry);
- while (follow_down(&fp_mnt, &fp_dentry) && d_mountpoint(fp_dentry));
+ if (!autofs4_follow_mount(&fp_mnt, &fp_dentry)) {
+ dput(fp_dentry);
+ mntput(fp_mnt);
+ dcache_dir_close(inode, file);
+ goto out;
+ }
fp = dentry_open(fp_dentry, fp_mnt, file->f_flags);
status = PTR_ERR(fp);
if (IS_ERR(fp)) {
- file->private_data = NULL;
- return status;
+ dcache_dir_close(inode, file);
+ goto out;
}
- file->private_data = fp;
+ cursor->d_fsdata = fp;
}
-out:
return 0;
+out:
+ return status;
}
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);
+ struct dentry *cursor = file->private_data;
+ int status = 0;
DPRINTK("file=%p dentry=%p %.*s",
file, dentry, dentry->d_name.len, dentry->d_name.name);
if (autofs4_ispending(dentry)) {
DPRINTK("dentry busy");
- return -EBUSY;
+ status = -EBUSY;
+ goto out;
}
if (d_mountpoint(dentry)) {
- struct file *fp = file->private_data;
-
- if (!fp)
- return -ENOENT;
-
+ struct file *fp = cursor->d_fsdata;
+ if (!fp) {
+ status = -ENOENT;
+ goto out;
+ }
filp_close(fp, current->files);
- file->private_data = NULL;
}
out:
- return 0;
+ dcache_dir_close(inode, file);
+ return status;
}
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);
+ struct dentry *cursor = file->private_data;
int status;
DPRINTK("file=%p dentry=%p %.*s",
}
if (d_mountpoint(dentry)) {
- struct file *fp = file->private_data;
+ struct file *fp = cursor->d_fsdata;
if (!fp)
return -ENOENT;
return status;
}
out:
- return autofs4_dcache_readdir(file, dirent, filldir);
+ return 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)
+static int try_to_fill_dentry(struct dentry *dentry, int flags)
{
- struct autofs_info *de_info = autofs4_dentry_ino(dentry);
+ struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);
+ struct autofs_info *ino = 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)) {
+ if (ino && (ino->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;
+
+ /*
+ * If the directory still exists the mount request must
+ * continue otherwise it can't be followed at the right
+ * time during the walk.
+ */
+ status = d_invalidate(dentry);
+ if (status != -EBUSY)
+ return -ENOENT;
}
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 */
+ /*
+ * 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 */
-
+ return status; /* 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;
+ return status;
} else if (status) {
/* Return a negative dentry, but leave it "pending" */
- return 1;
+ return status;
}
/* Trigger mount for path component or follow link */
} else if (flags & (LOOKUP_CONTINUE | LOOKUP_DIRECTORY) ||
spin_lock(&dentry->d_lock);
dentry->d_flags &= ~DCACHE_AUTOFS_PENDING;
spin_unlock(&dentry->d_lock);
- return 0;
+ return status;
}
}
- /* 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);
+ /* Initialize expiry counter after successful mount */
+ if (ino)
+ ino->last_used = jiffies;
spin_lock(&dentry->d_lock);
dentry->d_flags &= ~DCACHE_AUTOFS_PENDING;
spin_unlock(&dentry->d_lock);
- return 1;
+ return status;
+}
+
+/* For autofs direct mounts the follow link triggers the mount */
+static void *autofs4_follow_link(struct dentry *dentry, struct nameidata *nd)
+{
+ struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);
+ struct autofs_info *ino = autofs4_dentry_ino(dentry);
+ int oz_mode = autofs4_oz_mode(sbi);
+ unsigned int lookup_type;
+ int status;
+
+ DPRINTK("dentry=%p %.*s oz_mode=%d nd->flags=%d",
+ dentry, dentry->d_name.len, dentry->d_name.name, oz_mode,
+ nd->flags);
+
+ /* If it's our master or we shouldn't trigger a mount we're done */
+ lookup_type = nd->flags & (LOOKUP_CONTINUE | LOOKUP_DIRECTORY);
+ if (oz_mode || !lookup_type)
+ goto done;
+
+ /* If an expire request is pending wait for it. */
+ if (ino && (ino->flags & AUTOFS_INF_EXPIRING)) {
+ DPRINTK("waiting for active request %p name=%.*s",
+ dentry, dentry->d_name.len, dentry->d_name.name);
+
+ status = autofs4_wait(sbi, dentry, NFY_NONE);
+
+ DPRINTK("request done status=%d", status);
+ }
+
+ /*
+ * If the dentry contains directories then it is an
+ * autofs multi-mount with no root mount offset. So
+ * don't try to mount it again.
+ */
+ spin_lock(&dcache_lock);
+ if (!d_mountpoint(dentry) && list_empty(&dentry->d_subdirs)) {
+ spin_unlock(&dcache_lock);
+
+ status = try_to_fill_dentry(dentry, 0);
+ if (status)
+ goto out_error;
+
+ /*
+ * The mount succeeded but if there is no root mount
+ * it must be an autofs multi-mount with no root offset
+ * so we don't need to follow the mount.
+ */
+ if (d_mountpoint(dentry)) {
+ if (!autofs4_follow_mount(&nd->mnt, &nd->dentry)) {
+ status = -ENOENT;
+ goto out_error;
+ }
+ }
+
+ goto done;
+ }
+ spin_unlock(&dcache_lock);
+
+done:
+ return NULL;
+
+out_error:
+ path_release(nd);
+ return ERR_PTR(status);
}
/*
* yet completely filled in, and revalidate has to delay such
* lookups..
*/
-static int autofs4_revalidate(struct dentry * dentry, struct nameidata *nd)
+static int autofs4_revalidate(struct dentry *dentry, struct nameidata *nd)
{
- struct inode * dir = dentry->d_parent->d_inode;
+ 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;
+ int status = 0;
/* Pending dentry */
if (autofs4_ispending(dentry)) {
if (!oz_mode)
- status = try_to_fill_dentry(dentry, dir->i_sb, sbi, flags);
- return status;
+ status = try_to_fill_dentry(dentry, flags);
+ return !status;
}
/* Negative dentry.. invalidate if "old" */
if (dentry->d_inode == NULL)
- return (dentry->d_time - jiffies <= AUTOFS_NEGATIVE_TIMEOUT);
+ return 0;
/* 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)) {
+ __simple_empty(dentry)) {
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;
+ status = try_to_fill_dentry(dentry, 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)
+void autofs4_dentry_release(struct dentry *de)
{
struct autofs_info *inf;
DPRINTK("name = %.*s",
dentry->d_name.len, dentry->d_name.name);
+ /* File name too long to exist */
if (dentry->d_name.len > NAME_MAX)
- return ERR_PTR(-ENAMETOOLONG);/* File name too long to exist */
+ return ERR_PTR(-ENAMETOOLONG);
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);
d_add(dentry, NULL);
if (dentry->d_op && dentry->d_op->d_revalidate) {
- up(&dir->i_sem);
+ mutex_unlock(&dir->i_mutex);
(dentry->d_op->d_revalidate)(dentry, nd);
- down(&dir->i_sem);
+ mutex_lock(&dir->i_mutex);
}
/*
* 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) )
+ if (dentry->d_inode && d_unhashed(dentry))
return ERR_PTR(-ENOENT);
return NULL;
{
struct autofs_sb_info *sbi = autofs4_sbi(dir->i_sb);
struct autofs_info *ino = autofs4_dentry_ino(dentry);
+ struct autofs_info *p_ino;
struct inode *inode;
char *cp;
dentry->d_fsdata = ino;
ino->dentry = dget(dentry);
+ atomic_inc(&ino->count);
+ p_ino = autofs4_dentry_ino(dentry->d_parent);
+ if (p_ino && dentry->d_parent != dentry)
+ atomic_inc(&p_ino->count);
ino->inode = inode;
dir->i_mtime = CURRENT_TIME;
{
struct autofs_sb_info *sbi = autofs4_sbi(dir->i_sb);
struct autofs_info *ino = autofs4_dentry_ino(dentry);
+ struct autofs_info *p_ino;
/* This allows root to remove symlinks */
if ( !autofs4_oz_mode(sbi) && !capable(CAP_SYS_ADMIN) )
return -EACCES;
+ if (atomic_dec_and_test(&ino->count)) {
+ p_ino = autofs4_dentry_ino(dentry->d_parent);
+ if (p_ino && dentry->d_parent != dentry)
+ atomic_dec(&p_ino->count);
+ }
dput(ino->dentry);
dentry->d_inode->i_size = 0;
{
struct autofs_sb_info *sbi = autofs4_sbi(dir->i_sb);
struct autofs_info *ino = autofs4_dentry_ino(dentry);
+ struct autofs_info *p_ino;
if (!autofs4_oz_mode(sbi))
return -EACCES;
spin_unlock(&dentry->d_lock);
spin_unlock(&dcache_lock);
+ if (atomic_dec_and_test(&ino->count)) {
+ p_ino = autofs4_dentry_ino(dentry->d_parent);
+ if (p_ino && dentry->d_parent != dentry)
+ atomic_dec(&p_ino->count);
+ }
dput(ino->dentry);
-
dentry->d_inode->i_size = 0;
dentry->d_inode->i_nlink = 0;
{
struct autofs_sb_info *sbi = autofs4_sbi(dir->i_sb);
struct autofs_info *ino = autofs4_dentry_ino(dentry);
+ struct autofs_info *p_ino;
struct inode *inode;
if ( !autofs4_oz_mode(sbi) )
dentry->d_fsdata = ino;
ino->dentry = dget(dentry);
+ atomic_inc(&ino->count);
+ p_ino = autofs4_dentry_ino(dentry->d_parent);
+ if (p_ino && dentry->d_parent != dentry)
+ atomic_inc(&p_ino->count);
ino->inode = inode;
dir->i_nlink++;
dir->i_mtime = CURRENT_TIME;
{
int status = 0;
- if (may_umount(mnt) == 0)
+ if (may_umount(mnt))
status = 1;
DPRINTK("returning %d", status);
git://git.onelab.eu / linux-2.6.git / blobdiff