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-rw-r--r--fs/libfs.c359
1 files changed, 228 insertions, 131 deletions
diff --git a/fs/libfs.c b/fs/libfs.c
index a3accdf528a..88e3e00e2ec 100644
--- a/fs/libfs.c
+++ b/fs/libfs.c
@@ -3,19 +3,28 @@
* Library for filesystems writers.
*/
-#include <linux/module.h>
+#include <linux/blkdev.h>
+#include <linux/export.h>
#include <linux/pagemap.h>
#include <linux/slab.h>
#include <linux/mount.h>
#include <linux/vfs.h>
#include <linux/quotaops.h>
#include <linux/mutex.h>
+#include <linux/namei.h>
#include <linux/exportfs.h>
#include <linux/writeback.h>
-#include <linux/buffer_head.h>
+#include <linux/buffer_head.h> /* sync_mapping_buffers */
#include <asm/uaccess.h>
+#include "internal.h"
+
+static inline int simple_positive(struct dentry *dentry)
+{
+ return dentry->d_inode && !d_unhashed(dentry);
+}
+
int simple_getattr(struct vfsmount *mnt, struct dentry *dentry,
struct kstat *stat)
{
@@ -24,6 +33,7 @@ int simple_getattr(struct vfsmount *mnt, struct dentry *dentry,
stat->blocks = inode->i_mapping->nrpages << (PAGE_CACHE_SHIFT - 9);
return 0;
}
+EXPORT_SYMBOL(simple_getattr);
int simple_statfs(struct dentry *dentry, struct kstatfs *buf)
{
@@ -32,59 +42,67 @@ int simple_statfs(struct dentry *dentry, struct kstatfs *buf)
buf->f_namelen = NAME_MAX;
return 0;
}
+EXPORT_SYMBOL(simple_statfs);
/*
* Retaining negative dentries for an in-memory filesystem just wastes
* memory and lookup time: arrange for them to be deleted immediately.
*/
-static int simple_delete_dentry(struct dentry *dentry)
+int always_delete_dentry(const struct dentry *dentry)
{
return 1;
}
+EXPORT_SYMBOL(always_delete_dentry);
+
+const struct dentry_operations simple_dentry_operations = {
+ .d_delete = always_delete_dentry,
+};
+EXPORT_SYMBOL(simple_dentry_operations);
/*
* Lookup the data. This is trivial - if the dentry didn't already
* exist, we know it is negative. Set d_op to delete negative dentries.
*/
-struct dentry *simple_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd)
+struct dentry *simple_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
{
- static const struct dentry_operations simple_dentry_operations = {
- .d_delete = simple_delete_dentry,
- };
-
if (dentry->d_name.len > NAME_MAX)
return ERR_PTR(-ENAMETOOLONG);
- dentry->d_op = &simple_dentry_operations;
+ if (!dentry->d_sb->s_d_op)
+ d_set_d_op(dentry, &simple_dentry_operations);
d_add(dentry, NULL);
return NULL;
}
+EXPORT_SYMBOL(simple_lookup);
int dcache_dir_open(struct inode *inode, struct file *file)
{
- static struct qstr cursor_name = {.len = 1, .name = "."};
+ static struct qstr cursor_name = QSTR_INIT(".", 1);
file->private_data = d_alloc(file->f_path.dentry, &cursor_name);
return file->private_data ? 0 : -ENOMEM;
}
+EXPORT_SYMBOL(dcache_dir_open);
int dcache_dir_close(struct inode *inode, struct file *file)
{
dput(file->private_data);
return 0;
}
+EXPORT_SYMBOL(dcache_dir_close);
-loff_t dcache_dir_lseek(struct file *file, loff_t offset, int origin)
+loff_t dcache_dir_lseek(struct file *file, loff_t offset, int whence)
{
- mutex_lock(&file->f_path.dentry->d_inode->i_mutex);
- switch (origin) {
+ struct dentry *dentry = file->f_path.dentry;
+ mutex_lock(&dentry->d_inode->i_mutex);
+ switch (whence) {
case 1:
offset += file->f_pos;
case 0:
if (offset >= 0)
break;
default:
- mutex_unlock(&file->f_path.dentry->d_inode->i_mutex);
+ mutex_unlock(&dentry->d_inode->i_mutex);
return -EINVAL;
}
if (offset != file->f_pos) {
@@ -94,23 +112,27 @@ loff_t dcache_dir_lseek(struct file *file, loff_t offset, int origin)
struct dentry *cursor = file->private_data;
loff_t n = file->f_pos - 2;
- spin_lock(&dcache_lock);
+ spin_lock(&dentry->d_lock);
+ /* d_lock not required for cursor */
list_del(&cursor->d_u.d_child);
- p = file->f_path.dentry->d_subdirs.next;
- while (n && p != &file->f_path.dentry->d_subdirs) {
+ p = dentry->d_subdirs.next;
+ while (n && p != &dentry->d_subdirs) {
struct dentry *next;
next = list_entry(p, struct dentry, d_u.d_child);
- if (!d_unhashed(next) && next->d_inode)
+ spin_lock_nested(&next->d_lock, DENTRY_D_LOCK_NESTED);
+ if (simple_positive(next))
n--;
+ spin_unlock(&next->d_lock);
p = p->next;
}
list_add_tail(&cursor->d_u.d_child, p);
- spin_unlock(&dcache_lock);
+ spin_unlock(&dentry->d_lock);
}
}
- mutex_unlock(&file->f_path.dentry->d_inode->i_mutex);
+ mutex_unlock(&dentry->d_inode->i_mutex);
return offset;
}
+EXPORT_SYMBOL(dcache_dir_lseek);
/* Relationship between i_mode and the DT_xxx types */
static inline unsigned char dt_type(struct inode *inode)
@@ -124,74 +146,64 @@ static inline unsigned char dt_type(struct inode *inode)
* both impossible due to the lock on directory.
*/
-int dcache_readdir(struct file * filp, void * dirent, filldir_t filldir)
+int dcache_readdir(struct file *file, struct dir_context *ctx)
{
- struct dentry *dentry = filp->f_path.dentry;
- struct dentry *cursor = filp->private_data;
+ struct dentry *dentry = file->f_path.dentry;
+ struct dentry *cursor = file->private_data;
struct list_head *p, *q = &cursor->d_u.d_child;
- ino_t ino;
- int i = filp->f_pos;
- switch (i) {
- case 0:
- ino = dentry->d_inode->i_ino;
- if (filldir(dirent, ".", 1, i, ino, DT_DIR) < 0)
- break;
- filp->f_pos++;
- i++;
- /* fallthrough */
- case 1:
- ino = parent_ino(dentry);
- if (filldir(dirent, "..", 2, i, ino, DT_DIR) < 0)
- break;
- filp->f_pos++;
- i++;
- /* fallthrough */
- default:
- spin_lock(&dcache_lock);
- if (filp->f_pos == 2)
- list_move(q, &dentry->d_subdirs);
+ if (!dir_emit_dots(file, ctx))
+ return 0;
+ spin_lock(&dentry->d_lock);
+ if (ctx->pos == 2)
+ list_move(q, &dentry->d_subdirs);
+
+ for (p = q->next; p != &dentry->d_subdirs; p = p->next) {
+ struct dentry *next = list_entry(p, struct dentry, d_u.d_child);
+ spin_lock_nested(&next->d_lock, DENTRY_D_LOCK_NESTED);
+ if (!simple_positive(next)) {
+ spin_unlock(&next->d_lock);
+ continue;
+ }
- for (p=q->next; p != &dentry->d_subdirs; p=p->next) {
- struct dentry *next;
- next = list_entry(p, struct dentry, d_u.d_child);
- if (d_unhashed(next) || !next->d_inode)
- continue;
-
- spin_unlock(&dcache_lock);
- if (filldir(dirent, next->d_name.name,
- next->d_name.len, filp->f_pos,
- next->d_inode->i_ino,
- dt_type(next->d_inode)) < 0)
- return 0;
- spin_lock(&dcache_lock);
- /* next is still alive */
- list_move(q, p);
- p = q;
- filp->f_pos++;
- }
- spin_unlock(&dcache_lock);
+ spin_unlock(&next->d_lock);
+ spin_unlock(&dentry->d_lock);
+ if (!dir_emit(ctx, next->d_name.name, next->d_name.len,
+ next->d_inode->i_ino, dt_type(next->d_inode)))
+ return 0;
+ spin_lock(&dentry->d_lock);
+ spin_lock_nested(&next->d_lock, DENTRY_D_LOCK_NESTED);
+ /* next is still alive */
+ list_move(q, p);
+ spin_unlock(&next->d_lock);
+ p = q;
+ ctx->pos++;
}
+ spin_unlock(&dentry->d_lock);
return 0;
}
+EXPORT_SYMBOL(dcache_readdir);
ssize_t generic_read_dir(struct file *filp, char __user *buf, size_t siz, loff_t *ppos)
{
return -EISDIR;
}
+EXPORT_SYMBOL(generic_read_dir);
const struct file_operations simple_dir_operations = {
.open = dcache_dir_open,
.release = dcache_dir_close,
.llseek = dcache_dir_lseek,
.read = generic_read_dir,
- .readdir = dcache_readdir,
+ .iterate = dcache_readdir,
.fsync = noop_fsync,
};
+EXPORT_SYMBOL(simple_dir_operations);
const struct inode_operations simple_dir_inode_operations = {
.lookup = simple_lookup,
};
+EXPORT_SYMBOL(simple_dir_inode_operations);
static const struct super_operations simple_super_operations = {
.statfs = simple_statfs,
@@ -202,17 +214,18 @@ static const struct super_operations simple_super_operations = {
* will never be mountable)
*/
struct dentry *mount_pseudo(struct file_system_type *fs_type, char *name,
- const struct super_operations *ops, unsigned long magic)
+ const struct super_operations *ops,
+ const struct dentry_operations *dops, unsigned long magic)
{
- struct super_block *s = sget(fs_type, NULL, set_anon_super, NULL);
+ struct super_block *s;
struct dentry *dentry;
struct inode *root;
- struct qstr d_name = {.name = name, .len = strlen(name)};
+ struct qstr d_name = QSTR_INIT(name, strlen(name));
+ s = sget(fs_type, NULL, set_anon_super, MS_NOUSER, NULL);
if (IS_ERR(s))
return ERR_CAST(s);
- s->s_flags = MS_NOUSER;
s->s_maxbytes = MAX_LFS_FILESIZE;
s->s_blocksize = PAGE_SIZE;
s->s_blocksize_bits = PAGE_SHIFT;
@@ -230,15 +243,14 @@ struct dentry *mount_pseudo(struct file_system_type *fs_type, char *name,
root->i_ino = 1;
root->i_mode = S_IFDIR | S_IRUSR | S_IWUSR;
root->i_atime = root->i_mtime = root->i_ctime = CURRENT_TIME;
- dentry = d_alloc(NULL, &d_name);
+ dentry = __d_alloc(s, &d_name);
if (!dentry) {
iput(root);
goto Enomem;
}
- dentry->d_sb = s;
- dentry->d_parent = dentry;
d_instantiate(dentry, root);
s->s_root = dentry;
+ s->s_d_op = dops;
s->s_flags |= MS_ACTIVE;
return dget(s->s_root);
@@ -246,6 +258,15 @@ Enomem:
deactivate_locked_super(s);
return ERR_PTR(-ENOMEM);
}
+EXPORT_SYMBOL(mount_pseudo);
+
+int simple_open(struct inode *inode, struct file *file)
+{
+ if (inode->i_private)
+ file->private_data = inode->i_private;
+ return 0;
+}
+EXPORT_SYMBOL(simple_open);
int simple_link(struct dentry *old_dentry, struct inode *dir, struct dentry *dentry)
{
@@ -258,26 +279,28 @@ int simple_link(struct dentry *old_dentry, struct inode *dir, struct dentry *den
d_instantiate(dentry, inode);
return 0;
}
-
-static inline int simple_positive(struct dentry *dentry)
-{
- return dentry->d_inode && !d_unhashed(dentry);
-}
+EXPORT_SYMBOL(simple_link);
int simple_empty(struct dentry *dentry)
{
struct dentry *child;
int ret = 0;
- spin_lock(&dcache_lock);
- list_for_each_entry(child, &dentry->d_subdirs, d_u.d_child)
- if (simple_positive(child))
+ spin_lock(&dentry->d_lock);
+ list_for_each_entry(child, &dentry->d_subdirs, d_u.d_child) {
+ spin_lock_nested(&child->d_lock, DENTRY_D_LOCK_NESTED);
+ if (simple_positive(child)) {
+ spin_unlock(&child->d_lock);
goto out;
+ }
+ spin_unlock(&child->d_lock);
+ }
ret = 1;
out:
- spin_unlock(&dcache_lock);
+ spin_unlock(&dentry->d_lock);
return ret;
}
+EXPORT_SYMBOL(simple_empty);
int simple_unlink(struct inode *dir, struct dentry *dentry)
{
@@ -288,6 +311,7 @@ int simple_unlink(struct inode *dir, struct dentry *dentry)
dput(dentry);
return 0;
}
+EXPORT_SYMBOL(simple_unlink);
int simple_rmdir(struct inode *dir, struct dentry *dentry)
{
@@ -299,6 +323,7 @@ int simple_rmdir(struct inode *dir, struct dentry *dentry)
drop_nlink(dir);
return 0;
}
+EXPORT_SYMBOL(simple_rmdir);
int simple_rename(struct inode *old_dir, struct dentry *old_dentry,
struct inode *new_dir, struct dentry *new_dentry)
@@ -311,8 +336,10 @@ int simple_rename(struct inode *old_dir, struct dentry *old_dentry,
if (new_dentry->d_inode) {
simple_unlink(new_dir, new_dentry);
- if (they_are_dirs)
+ if (they_are_dirs) {
+ drop_nlink(new_dentry->d_inode);
drop_nlink(old_dir);
+ }
} else if (they_are_dirs) {
drop_nlink(old_dir);
inc_nlink(new_dir);
@@ -323,6 +350,7 @@ int simple_rename(struct inode *old_dir, struct dentry *old_dentry,
return 0;
}
+EXPORT_SYMBOL(simple_rename);
/**
* simple_setattr - setattr for simple filesystem
@@ -343,8 +371,6 @@ int simple_setattr(struct dentry *dentry, struct iattr *iattr)
struct inode *inode = dentry->d_inode;
int error;
- WARN_ON_ONCE(inode->i_op->truncate);
-
error = inode_change_ok(inode, iattr);
if (error)
return error;
@@ -365,6 +391,7 @@ int simple_readpage(struct file *file, struct page *page)
unlock_page(page);
return 0;
}
+EXPORT_SYMBOL(simple_readpage);
int simple_write_begin(struct file *file, struct address_space *mapping,
loff_t pos, unsigned len, unsigned flags,
@@ -388,6 +415,7 @@ int simple_write_begin(struct file *file, struct address_space *mapping,
}
return 0;
}
+EXPORT_SYMBOL(simple_write_begin);
/**
* simple_write_end - .write_end helper for non-block-device FSes
@@ -439,6 +467,7 @@ int simple_write_end(struct file *file, struct address_space *mapping,
return copied;
}
+EXPORT_SYMBOL(simple_write_end);
/*
* the inodes created here are not hashed. If you use iunique to generate
@@ -471,12 +500,10 @@ int simple_fill_super(struct super_block *s, unsigned long magic,
inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
inode->i_op = &simple_dir_inode_operations;
inode->i_fop = &simple_dir_operations;
- inode->i_nlink = 2;
- root = d_alloc_root(inode);
- if (!root) {
- iput(inode);
+ set_nlink(inode, 2);
+ root = d_make_root(inode);
+ if (!root)
return -ENOMEM;
- }
for (i = 0; !files->name || files->name[0]; i++, files++) {
if (!files->name)
continue;
@@ -491,8 +518,10 @@ int simple_fill_super(struct super_block *s, unsigned long magic,
if (!dentry)
goto out;
inode = new_inode(s);
- if (!inode)
+ if (!inode) {
+ dput(dentry);
goto out;
+ }
inode->i_mode = S_IFREG | files->mode;
inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
inode->i_fop = files->ops;
@@ -503,9 +532,11 @@ int simple_fill_super(struct super_block *s, unsigned long magic,
return 0;
out:
d_genocide(root);
+ shrink_dcache_parent(root);
dput(root);
return -ENOMEM;
}
+EXPORT_SYMBOL(simple_fill_super);
static DEFINE_SPINLOCK(pin_fs_lock);
@@ -515,7 +546,7 @@ int simple_pin_fs(struct file_system_type *type, struct vfsmount **mount, int *c
spin_lock(&pin_fs_lock);
if (unlikely(!*mount)) {
spin_unlock(&pin_fs_lock);
- mnt = vfs_kern_mount(type, 0, type->name, NULL);
+ mnt = vfs_kern_mount(type, MS_KERNMOUNT, type->name, NULL);
if (IS_ERR(mnt))
return PTR_ERR(mnt);
spin_lock(&pin_fs_lock);
@@ -528,6 +559,7 @@ int simple_pin_fs(struct file_system_type *type, struct vfsmount **mount, int *c
mntput(mnt);
return 0;
}
+EXPORT_SYMBOL(simple_pin_fs);
void simple_release_fs(struct vfsmount **mount, int *count)
{
@@ -539,6 +571,7 @@ void simple_release_fs(struct vfsmount **mount, int *count)
spin_unlock(&pin_fs_lock);
mntput(mnt);
}
+EXPORT_SYMBOL(simple_release_fs);
/**
* simple_read_from_buffer - copy data from the buffer to user space
@@ -573,6 +606,7 @@ ssize_t simple_read_from_buffer(void __user *to, size_t count, loff_t *ppos,
*ppos = pos + count;
return count;
}
+EXPORT_SYMBOL(simple_read_from_buffer);
/**
* simple_write_to_buffer - copy data from user space to the buffer
@@ -607,6 +641,7 @@ ssize_t simple_write_to_buffer(void *to, size_t available, loff_t *ppos,
*ppos = pos + count;
return count;
}
+EXPORT_SYMBOL(simple_write_to_buffer);
/**
* memory_read_from_buffer - copy data from the buffer
@@ -638,6 +673,7 @@ ssize_t memory_read_from_buffer(void *to, size_t count, loff_t *ppos,
return count;
}
+EXPORT_SYMBOL(memory_read_from_buffer);
/*
* Transaction based IO.
@@ -659,6 +695,7 @@ void simple_transaction_set(struct file *file, size_t n)
smp_mb();
ar->size = n;
}
+EXPORT_SYMBOL(simple_transaction_set);
char *simple_transaction_get(struct file *file, const char __user *buf, size_t size)
{
@@ -690,6 +727,7 @@ char *simple_transaction_get(struct file *file, const char __user *buf, size_t s
return ar->data;
}
+EXPORT_SYMBOL(simple_transaction_get);
ssize_t simple_transaction_read(struct file *file, char __user *buf, size_t size, loff_t *pos)
{
@@ -699,12 +737,14 @@ ssize_t simple_transaction_read(struct file *file, char __user *buf, size_t size
return 0;
return simple_read_from_buffer(buf, size, pos, ar->data, ar->size);
}
+EXPORT_SYMBOL(simple_transaction_read);
int simple_transaction_release(struct inode *inode, struct file *file)
{
free_page((unsigned long)file->private_data);
return 0;
}
+EXPORT_SYMBOL(simple_transaction_release);
/* Simple attribute files */
@@ -740,12 +780,14 @@ int simple_attr_open(struct inode *inode, struct file *file,
return nonseekable_open(inode, file);
}
+EXPORT_SYMBOL_GPL(simple_attr_open);
int simple_attr_release(struct inode *inode, struct file *file)
{
kfree(file->private_data);
return 0;
}
+EXPORT_SYMBOL_GPL(simple_attr_release); /* GPL-only? This? Really? */
/* read from the buffer that is filled with the get function */
ssize_t simple_attr_read(struct file *file, char __user *buf,
@@ -781,6 +823,7 @@ out:
mutex_unlock(&attr->mutex);
return ret;
}
+EXPORT_SYMBOL_GPL(simple_attr_read);
/* interpret the buffer as a number to call the set function with */
ssize_t simple_attr_write(struct file *file, const char __user *buf,
@@ -805,7 +848,7 @@ ssize_t simple_attr_write(struct file *file, const char __user *buf,
goto out;
attr->set_buf[size] = '\0';
- val = simple_strtol(attr->set_buf, NULL, 0);
+ val = simple_strtoll(attr->set_buf, NULL, 0);
ret = attr->set(attr->data, val);
if (ret == 0)
ret = len; /* on success, claim we got the whole input */
@@ -813,6 +856,7 @@ out:
mutex_unlock(&attr->mutex);
return ret;
}
+EXPORT_SYMBOL_GPL(simple_attr_write);
/**
* generic_fh_to_dentry - generic helper for the fh_to_dentry export operation
@@ -847,7 +891,7 @@ struct dentry *generic_fh_to_dentry(struct super_block *sb, struct fid *fid,
EXPORT_SYMBOL_GPL(generic_fh_to_dentry);
/**
- * generic_fh_to_dentry - generic helper for the fh_to_parent export operation
+ * generic_fh_to_parent - generic helper for the fh_to_parent export operation
* @sb: filesystem to do the file handle conversion on
* @fid: file handle to convert
* @fh_len: length of the file handle in bytes
@@ -880,31 +924,66 @@ struct dentry *generic_fh_to_parent(struct super_block *sb, struct fid *fid,
EXPORT_SYMBOL_GPL(generic_fh_to_parent);
/**
- * generic_file_fsync - generic fsync implementation for simple filesystems
+ * __generic_file_fsync - generic fsync implementation for simple filesystems
+ *
* @file: file to synchronize
+ * @start: start offset in bytes
+ * @end: end offset in bytes (inclusive)
* @datasync: only synchronize essential metadata if true
*
* This is a generic implementation of the fsync method for simple
* filesystems which track all non-inode metadata in the buffers list
* hanging off the address_space structure.
*/
-int generic_file_fsync(struct file *file, int datasync)
+int __generic_file_fsync(struct file *file, loff_t start, loff_t end,
+ int datasync)
{
struct inode *inode = file->f_mapping->host;
int err;
int ret;
+ err = filemap_write_and_wait_range(inode->i_mapping, start, end);
+ if (err)
+ return err;
+
+ mutex_lock(&inode->i_mutex);
ret = sync_mapping_buffers(inode->i_mapping);
if (!(inode->i_state & I_DIRTY))
- return ret;
+ goto out;
if (datasync && !(inode->i_state & I_DIRTY_DATASYNC))
- return ret;
+ goto out;
err = sync_inode_metadata(inode, 1);
if (ret == 0)
ret = err;
+
+out:
+ mutex_unlock(&inode->i_mutex);
return ret;
}
+EXPORT_SYMBOL(__generic_file_fsync);
+
+/**
+ * generic_file_fsync - generic fsync implementation for simple filesystems
+ * with flush
+ * @file: file to synchronize
+ * @start: start offset in bytes
+ * @end: end offset in bytes (inclusive)
+ * @datasync: only synchronize essential metadata if true
+ *
+ */
+
+int generic_file_fsync(struct file *file, loff_t start, loff_t end,
+ int datasync)
+{
+ struct inode *inode = file->f_mapping->host;
+ int err;
+
+ err = __generic_file_fsync(file, start, end, datasync);
+ if (err)
+ return err;
+ return blkdev_issue_flush(inode->i_sb->s_bdev, GFP_KERNEL, NULL);
+}
EXPORT_SYMBOL(generic_file_fsync);
/**
@@ -939,42 +1018,60 @@ EXPORT_SYMBOL(generic_check_addressable);
/*
* No-op implementation of ->fsync for in-memory filesystems.
*/
-int noop_fsync(struct file *file, int datasync)
+int noop_fsync(struct file *file, loff_t start, loff_t end, int datasync)
{
return 0;
}
-
-EXPORT_SYMBOL(dcache_dir_close);
-EXPORT_SYMBOL(dcache_dir_lseek);
-EXPORT_SYMBOL(dcache_dir_open);
-EXPORT_SYMBOL(dcache_readdir);
-EXPORT_SYMBOL(generic_read_dir);
-EXPORT_SYMBOL(mount_pseudo);
-EXPORT_SYMBOL(simple_write_begin);
-EXPORT_SYMBOL(simple_write_end);
-EXPORT_SYMBOL(simple_dir_inode_operations);
-EXPORT_SYMBOL(simple_dir_operations);
-EXPORT_SYMBOL(simple_empty);
-EXPORT_SYMBOL(simple_fill_super);
-EXPORT_SYMBOL(simple_getattr);
-EXPORT_SYMBOL(simple_link);
-EXPORT_SYMBOL(simple_lookup);
-EXPORT_SYMBOL(simple_pin_fs);
-EXPORT_SYMBOL(simple_readpage);
-EXPORT_SYMBOL(simple_release_fs);
-EXPORT_SYMBOL(simple_rename);
-EXPORT_SYMBOL(simple_rmdir);
-EXPORT_SYMBOL(simple_statfs);
EXPORT_SYMBOL(noop_fsync);
-EXPORT_SYMBOL(simple_unlink);
-EXPORT_SYMBOL(simple_read_from_buffer);
-EXPORT_SYMBOL(simple_write_to_buffer);
-EXPORT_SYMBOL(memory_read_from_buffer);
-EXPORT_SYMBOL(simple_transaction_set);
-EXPORT_SYMBOL(simple_transaction_get);
-EXPORT_SYMBOL(simple_transaction_read);
-EXPORT_SYMBOL(simple_transaction_release);
-EXPORT_SYMBOL_GPL(simple_attr_open);
-EXPORT_SYMBOL_GPL(simple_attr_release);
-EXPORT_SYMBOL_GPL(simple_attr_read);
-EXPORT_SYMBOL_GPL(simple_attr_write);
+
+void kfree_put_link(struct dentry *dentry, struct nameidata *nd,
+ void *cookie)
+{
+ char *s = nd_get_link(nd);
+ if (!IS_ERR(s))
+ kfree(s);
+}
+EXPORT_SYMBOL(kfree_put_link);
+
+/*
+ * nop .set_page_dirty method so that people can use .page_mkwrite on
+ * anon inodes.
+ */
+static int anon_set_page_dirty(struct page *page)
+{
+ return 0;
+};
+
+/*
+ * A single inode exists for all anon_inode files. Contrary to pipes,
+ * anon_inode inodes have no associated per-instance data, so we need
+ * only allocate one of them.
+ */
+struct inode *alloc_anon_inode(struct super_block *s)
+{
+ static const struct address_space_operations anon_aops = {
+ .set_page_dirty = anon_set_page_dirty,
+ };
+ struct inode *inode = new_inode_pseudo(s);
+
+ if (!inode)
+ return ERR_PTR(-ENOMEM);
+
+ inode->i_ino = get_next_ino();
+ inode->i_mapping->a_ops = &anon_aops;
+
+ /*
+ * Mark the inode dirty from the very beginning,
+ * that way it will never be moved to the dirty
+ * list because mark_inode_dirty() will think
+ * that it already _is_ on the dirty list.
+ */
+ inode->i_state = I_DIRTY;
+ inode->i_mode = S_IRUSR | S_IWUSR;
+ inode->i_uid = current_fsuid();
+ inode->i_gid = current_fsgid();
+ inode->i_flags |= S_PRIVATE;
+ inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
+ return inode;
+}
+EXPORT_SYMBOL(alloc_anon_inode);