+++ /dev/null
-/*
- * Copyright (C) 2002 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
- * Licensed under the GPL
- */
-
-#include <linux/ctype.h>
-#include <linux/dcache.h>
-#include <linux/file.h>
-#include <linux/fs.h>
-#include <linux/init.h>
-#include <linux/kernel.h>
-#include <linux/list.h>
-#include <linux/module.h>
-#include <linux/mount.h>
-#include <linux/slab.h>
-#include <linux/statfs.h>
-#include <linux/types.h>
-#include <linux/pid_namespace.h>
-#include <linux/namei.h>
-#include <asm/uaccess.h>
-#include <os.h>
-
-static struct inode *get_inode(struct super_block *, struct dentry *);
-
-struct hppfs_data {
- struct list_head list;
- char contents[PAGE_SIZE - sizeof(struct list_head)];
-};
-
-struct hppfs_private {
- struct file *proc_file;
- int host_fd;
- loff_t len;
- struct hppfs_data *contents;
-};
-
-struct hppfs_inode_info {
- struct dentry *proc_dentry;
- struct inode vfs_inode;
-};
-
-static inline struct hppfs_inode_info *HPPFS_I(struct inode *inode)
-{
- return container_of(inode, struct hppfs_inode_info, vfs_inode);
-}
-
-#define HPPFS_SUPER_MAGIC 0xb00000ee
-
-static const struct super_operations hppfs_sbops;
-
-static int is_pid(struct dentry *dentry)
-{
- struct super_block *sb;
- int i;
-
- sb = dentry->d_sb;
- if (dentry->d_parent != sb->s_root)
- return 0;
-
- for (i = 0; i < dentry->d_name.len; i++) {
- if (!isdigit(dentry->d_name.name[i]))
- return 0;
- }
- return 1;
-}
-
-static char *dentry_name(struct dentry *dentry, int extra)
-{
- struct dentry *parent;
- char *root, *name;
- const char *seg_name;
- int len, seg_len, root_len;
-
- len = 0;
- parent = dentry;
- while (parent->d_parent != parent) {
- if (is_pid(parent))
- len += strlen("pid") + 1;
- else len += parent->d_name.len + 1;
- parent = parent->d_parent;
- }
-
- root = "proc";
- root_len = strlen(root);
- len += root_len;
- name = kmalloc(len + extra + 1, GFP_KERNEL);
- if (name == NULL)
- return NULL;
-
- name[len] = '\0';
- parent = dentry;
- while (parent->d_parent != parent) {
- if (is_pid(parent)) {
- seg_name = "pid";
- seg_len = strlen(seg_name);
- }
- else {
- seg_name = parent->d_name.name;
- seg_len = parent->d_name.len;
- }
-
- len -= seg_len + 1;
- name[len] = '/';
- memcpy(&name[len + 1], seg_name, seg_len);
- parent = parent->d_parent;
- }
- memcpy(name, root, root_len);
- return name;
-}
-
-static int file_removed(struct dentry *dentry, const char *file)
-{
- char *host_file;
- int extra, fd;
-
- extra = 0;
- if (file != NULL)
- extra += strlen(file) + 1;
-
- host_file = dentry_name(dentry, extra + strlen("/remove"));
- if (host_file == NULL) {
- printk(KERN_ERR "file_removed : allocation failed\n");
- return -ENOMEM;
- }
-
- if (file != NULL) {
- strcat(host_file, "/");
- strcat(host_file, file);
- }
- strcat(host_file, "/remove");
-
- fd = os_open_file(host_file, of_read(OPENFLAGS()), 0);
- kfree(host_file);
- if (fd > 0) {
- os_close_file(fd);
- return 1;
- }
- return 0;
-}
-
-static struct dentry *hppfs_lookup(struct inode *ino, struct dentry *dentry,
- unsigned int flags)
-{
- struct dentry *proc_dentry, *parent;
- struct qstr *name = &dentry->d_name;
- struct inode *inode;
- int err, deleted;
-
- deleted = file_removed(dentry, NULL);
- if (deleted < 0)
- return ERR_PTR(deleted);
- else if (deleted)
- return ERR_PTR(-ENOENT);
-
- parent = HPPFS_I(ino)->proc_dentry;
- mutex_lock(&d_inode(parent)->i_mutex);
- proc_dentry = lookup_one_len(name->name, parent, name->len);
- mutex_unlock(&d_inode(parent)->i_mutex);
-
- if (IS_ERR(proc_dentry))
- return proc_dentry;
-
- err = -ENOMEM;
- inode = get_inode(ino->i_sb, proc_dentry);
- if (!inode)
- goto out;
-
- d_add(dentry, inode);
- return NULL;
-
- out:
- return ERR_PTR(err);
-}
-
-static const struct inode_operations hppfs_file_iops = {
-};
-
-static ssize_t read_proc(struct file *file, char __user *buf, ssize_t count,
- loff_t *ppos, int is_user)
-{
- ssize_t (*read)(struct file *, char __user *, size_t, loff_t *);
- ssize_t n;
-
- read = file_inode(file)->i_fop->read;
-
- if (!is_user)
- set_fs(KERNEL_DS);
-
- n = (*read)(file, buf, count, &file->f_pos);
-
- if (!is_user)
- set_fs(USER_DS);
-
- if (ppos)
- *ppos = file->f_pos;
- return n;
-}
-
-static ssize_t hppfs_read_file(int fd, char __user *buf, ssize_t count)
-{
- ssize_t n;
- int cur, err;
- char *new_buf;
-
- n = -ENOMEM;
- new_buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
- if (new_buf == NULL) {
- printk(KERN_ERR "hppfs_read_file : kmalloc failed\n");
- goto out;
- }
- n = 0;
- while (count > 0) {
- cur = min_t(ssize_t, count, PAGE_SIZE);
- err = os_read_file(fd, new_buf, cur);
- if (err < 0) {
- printk(KERN_ERR "hppfs_read : read failed, "
- "errno = %d\n", err);
- n = err;
- goto out_free;
- } else if (err == 0)
- break;
-
- if (copy_to_user(buf, new_buf, err)) {
- n = -EFAULT;
- goto out_free;
- }
- n += err;
- count -= err;
- }
- out_free:
- kfree(new_buf);
- out:
- return n;
-}
-
-static ssize_t hppfs_read(struct file *file, char __user *buf, size_t count,
- loff_t *ppos)
-{
- struct hppfs_private *hppfs = file->private_data;
- struct hppfs_data *data;
- loff_t off;
- int err;
-
- if (hppfs->contents != NULL) {
- int rem;
-
- if (*ppos >= hppfs->len)
- return 0;
-
- data = hppfs->contents;
- off = *ppos;
- while (off >= sizeof(data->contents)) {
- data = list_entry(data->list.next, struct hppfs_data,
- list);
- off -= sizeof(data->contents);
- }
-
- if (off + count > hppfs->len)
- count = hppfs->len - off;
- rem = copy_to_user(buf, &data->contents[off], count);
- *ppos += count - rem;
- if (rem > 0)
- return -EFAULT;
- } else if (hppfs->host_fd != -1) {
- err = os_seek_file(hppfs->host_fd, *ppos);
- if (err) {
- printk(KERN_ERR "hppfs_read : seek failed, "
- "errno = %d\n", err);
- return err;
- }
- err = hppfs_read_file(hppfs->host_fd, buf, count);
- if (err < 0) {
- printk(KERN_ERR "hppfs_read: read failed: %d\n", err);
- return err;
- }
- count = err;
- if (count > 0)
- *ppos += count;
- }
- else count = read_proc(hppfs->proc_file, buf, count, ppos, 1);
-
- return count;
-}
-
-static ssize_t hppfs_write(struct file *file, const char __user *buf,
- size_t len, loff_t *ppos)
-{
- struct hppfs_private *data = file->private_data;
- struct file *proc_file = data->proc_file;
- ssize_t (*write)(struct file *, const char __user *, size_t, loff_t *);
-
- write = file_inode(proc_file)->i_fop->write;
- return (*write)(proc_file, buf, len, ppos);
-}
-
-static int open_host_sock(char *host_file, int *filter_out)
-{
- char *end;
- int fd;
-
- end = &host_file[strlen(host_file)];
- strcpy(end, "/rw");
- *filter_out = 1;
- fd = os_connect_socket(host_file);
- if (fd > 0)
- return fd;
-
- strcpy(end, "/r");
- *filter_out = 0;
- fd = os_connect_socket(host_file);
- return fd;
-}
-
-static void free_contents(struct hppfs_data *head)
-{
- struct hppfs_data *data;
- struct list_head *ele, *next;
-
- if (head == NULL)
- return;
-
- list_for_each_safe(ele, next, &head->list) {
- data = list_entry(ele, struct hppfs_data, list);
- kfree(data);
- }
- kfree(head);
-}
-
-static struct hppfs_data *hppfs_get_data(int fd, int filter,
- struct file *proc_file,
- struct file *hppfs_file,
- loff_t *size_out)
-{
- struct hppfs_data *data, *new, *head;
- int n, err;
-
- err = -ENOMEM;
- data = kmalloc(sizeof(*data), GFP_KERNEL);
- if (data == NULL) {
- printk(KERN_ERR "hppfs_get_data : head allocation failed\n");
- goto failed;
- }
-
- INIT_LIST_HEAD(&data->list);
-
- head = data;
- *size_out = 0;
-
- if (filter) {
- while ((n = read_proc(proc_file, data->contents,
- sizeof(data->contents), NULL, 0)) > 0)
- os_write_file(fd, data->contents, n);
- err = os_shutdown_socket(fd, 0, 1);
- if (err) {
- printk(KERN_ERR "hppfs_get_data : failed to shut down "
- "socket\n");
- goto failed_free;
- }
- }
- while (1) {
- n = os_read_file(fd, data->contents, sizeof(data->contents));
- if (n < 0) {
- err = n;
- printk(KERN_ERR "hppfs_get_data : read failed, "
- "errno = %d\n", err);
- goto failed_free;
- } else if (n == 0)
- break;
-
- *size_out += n;
-
- if (n < sizeof(data->contents))
- break;
-
- new = kmalloc(sizeof(*data), GFP_KERNEL);
- if (new == 0) {
- printk(KERN_ERR "hppfs_get_data : data allocation "
- "failed\n");
- err = -ENOMEM;
- goto failed_free;
- }
-
- INIT_LIST_HEAD(&new->list);
- list_add(&new->list, &data->list);
- data = new;
- }
- return head;
-
- failed_free:
- free_contents(head);
- failed:
- return ERR_PTR(err);
-}
-
-static struct hppfs_private *hppfs_data(void)
-{
- struct hppfs_private *data;
-
- data = kmalloc(sizeof(*data), GFP_KERNEL);
- if (data == NULL)
- return data;
-
- *data = ((struct hppfs_private ) { .host_fd = -1,
- .len = -1,
- .contents = NULL } );
- return data;
-}
-
-static int file_mode(int fmode)
-{
- if (fmode == (FMODE_READ | FMODE_WRITE))
- return O_RDWR;
- if (fmode == FMODE_READ)
- return O_RDONLY;
- if (fmode == FMODE_WRITE)
- return O_WRONLY;
- return 0;
-}
-
-static int hppfs_open(struct inode *inode, struct file *file)
-{
- const struct cred *cred = file->f_cred;
- struct hppfs_private *data;
- struct path path;
- char *host_file;
- int err, fd, type, filter;
-
- err = -ENOMEM;
- data = hppfs_data();
- if (data == NULL)
- goto out;
-
- host_file = dentry_name(file->f_path.dentry, strlen("/rw"));
- if (host_file == NULL)
- goto out_free2;
-
- path.mnt = inode->i_sb->s_fs_info;
- path.dentry = HPPFS_I(inode)->proc_dentry;
-
- data->proc_file = dentry_open(&path, file_mode(file->f_mode), cred);
- err = PTR_ERR(data->proc_file);
- if (IS_ERR(data->proc_file))
- goto out_free1;
-
- type = os_file_type(host_file);
- if (type == OS_TYPE_FILE) {
- fd = os_open_file(host_file, of_read(OPENFLAGS()), 0);
- if (fd >= 0)
- data->host_fd = fd;
- else
- printk(KERN_ERR "hppfs_open : failed to open '%s', "
- "errno = %d\n", host_file, -fd);
-
- data->contents = NULL;
- } else if (type == OS_TYPE_DIR) {
- fd = open_host_sock(host_file, &filter);
- if (fd > 0) {
- data->contents = hppfs_get_data(fd, filter,
- data->proc_file,
- file, &data->len);
- if (!IS_ERR(data->contents))
- data->host_fd = fd;
- } else
- printk(KERN_ERR "hppfs_open : failed to open a socket "
- "in '%s', errno = %d\n", host_file, -fd);
- }
- kfree(host_file);
-
- file->private_data = data;
- return 0;
-
- out_free1:
- kfree(host_file);
- out_free2:
- free_contents(data->contents);
- kfree(data);
- out:
- return err;
-}
-
-static int hppfs_dir_open(struct inode *inode, struct file *file)
-{
- const struct cred *cred = file->f_cred;
- struct hppfs_private *data;
- struct path path;
- int err;
-
- err = -ENOMEM;
- data = hppfs_data();
- if (data == NULL)
- goto out;
-
- path.mnt = inode->i_sb->s_fs_info;
- path.dentry = HPPFS_I(inode)->proc_dentry;
- data->proc_file = dentry_open(&path, file_mode(file->f_mode), cred);
- err = PTR_ERR(data->proc_file);
- if (IS_ERR(data->proc_file))
- goto out_free;
-
- file->private_data = data;
- return 0;
-
- out_free:
- kfree(data);
- out:
- return err;
-}
-
-static loff_t hppfs_llseek(struct file *file, loff_t off, int where)
-{
- struct hppfs_private *data = file->private_data;
- struct file *proc_file = data->proc_file;
- loff_t (*llseek)(struct file *, loff_t, int);
- loff_t ret;
-
- llseek = file_inode(proc_file)->i_fop->llseek;
- if (llseek != NULL) {
- ret = (*llseek)(proc_file, off, where);
- if (ret < 0)
- return ret;
- }
-
- return default_llseek(file, off, where);
-}
-
-static int hppfs_release(struct inode *inode, struct file *file)
-{
- struct hppfs_private *data = file->private_data;
- struct file *proc_file = data->proc_file;
- if (proc_file)
- fput(proc_file);
- kfree(data);
- return 0;
-}
-
-static const struct file_operations hppfs_file_fops = {
- .owner = NULL,
- .llseek = hppfs_llseek,
- .read = hppfs_read,
- .write = hppfs_write,
- .open = hppfs_open,
- .release = hppfs_release,
-};
-
-struct hppfs_dirent {
- struct dir_context ctx;
- struct dir_context *caller;
- struct dentry *dentry;
-};
-
-static int hppfs_filldir(struct dir_context *ctx, const char *name, int size,
- loff_t offset, u64 inode, unsigned int type)
-{
- struct hppfs_dirent *dirent =
- container_of(ctx, struct hppfs_dirent, ctx);
-
- if (file_removed(dirent->dentry, name))
- return 0;
-
- dirent->caller->pos = dirent->ctx.pos;
- return !dir_emit(dirent->caller, name, size, inode, type);
-}
-
-static int hppfs_readdir(struct file *file, struct dir_context *ctx)
-{
- struct hppfs_private *data = file->private_data;
- struct file *proc_file = data->proc_file;
- struct hppfs_dirent d = {
- .ctx.actor = hppfs_filldir,
- .caller = ctx,
- .dentry = file->f_path.dentry
- };
- int err;
- proc_file->f_pos = ctx->pos;
- err = iterate_dir(proc_file, &d.ctx);
- ctx->pos = d.ctx.pos;
- return err;
-}
-
-static const struct file_operations hppfs_dir_fops = {
- .owner = NULL,
- .iterate = hppfs_readdir,
- .open = hppfs_dir_open,
- .llseek = default_llseek,
- .release = hppfs_release,
-};
-
-static int hppfs_statfs(struct dentry *dentry, struct kstatfs *sf)
-{
- sf->f_blocks = 0;
- sf->f_bfree = 0;
- sf->f_bavail = 0;
- sf->f_files = 0;
- sf->f_ffree = 0;
- sf->f_type = HPPFS_SUPER_MAGIC;
- return 0;
-}
-
-static struct inode *hppfs_alloc_inode(struct super_block *sb)
-{
- struct hppfs_inode_info *hi;
-
- hi = kmalloc(sizeof(*hi), GFP_KERNEL);
- if (!hi)
- return NULL;
-
- hi->proc_dentry = NULL;
- inode_init_once(&hi->vfs_inode);
- return &hi->vfs_inode;
-}
-
-void hppfs_evict_inode(struct inode *ino)
-{
- clear_inode(ino);
- dput(HPPFS_I(ino)->proc_dentry);
- mntput(ino->i_sb->s_fs_info);
-}
-
-static void hppfs_i_callback(struct rcu_head *head)
-{
- struct inode *inode = container_of(head, struct inode, i_rcu);
- kfree(HPPFS_I(inode));
-}
-
-static void hppfs_destroy_inode(struct inode *inode)
-{
- call_rcu(&inode->i_rcu, hppfs_i_callback);
-}
-
-static const struct super_operations hppfs_sbops = {
- .alloc_inode = hppfs_alloc_inode,
- .destroy_inode = hppfs_destroy_inode,
- .evict_inode = hppfs_evict_inode,
- .statfs = hppfs_statfs,
-};
-
-static int hppfs_readlink(struct dentry *dentry, char __user *buffer,
- int buflen)
-{
- struct dentry *proc_dentry = HPPFS_I(d_inode(dentry))->proc_dentry;
- return d_inode(proc_dentry)->i_op->readlink(proc_dentry, buffer,
- buflen);
-}
-
-static void *hppfs_follow_link(struct dentry *dentry, struct nameidata *nd)
-{
- struct dentry *proc_dentry = HPPFS_I(d_inode(dentry))->proc_dentry;
-
- return d_inode(proc_dentry)->i_op->follow_link(proc_dentry, nd);
-}
-
-static void hppfs_put_link(struct dentry *dentry, struct nameidata *nd,
- void *cookie)
-{
- struct dentry *proc_dentry = HPPFS_I(d_inode(dentry))->proc_dentry;
-
- if (d_inode(proc_dentry)->i_op->put_link)
- d_inode(proc_dentry)->i_op->put_link(proc_dentry, nd, cookie);
-}
-
-static const struct inode_operations hppfs_dir_iops = {
- .lookup = hppfs_lookup,
-};
-
-static const struct inode_operations hppfs_link_iops = {
- .readlink = hppfs_readlink,
- .follow_link = hppfs_follow_link,
- .put_link = hppfs_put_link,
-};
-
-static struct inode *get_inode(struct super_block *sb, struct dentry *dentry)
-{
- struct inode *proc_ino = d_inode(dentry);
- struct inode *inode = new_inode(sb);
-
- if (!inode) {
- dput(dentry);
- return NULL;
- }
-
- if (d_is_dir(dentry)) {
- inode->i_op = &hppfs_dir_iops;
- inode->i_fop = &hppfs_dir_fops;
- } else if (d_is_symlink(dentry)) {
- inode->i_op = &hppfs_link_iops;
- inode->i_fop = &hppfs_file_fops;
- } else {
- inode->i_op = &hppfs_file_iops;
- inode->i_fop = &hppfs_file_fops;
- }
-
- HPPFS_I(inode)->proc_dentry = dentry;
-
- inode->i_uid = proc_ino->i_uid;
- inode->i_gid = proc_ino->i_gid;
- inode->i_atime = proc_ino->i_atime;
- inode->i_mtime = proc_ino->i_mtime;
- inode->i_ctime = proc_ino->i_ctime;
- inode->i_ino = proc_ino->i_ino;
- inode->i_mode = proc_ino->i_mode;
- set_nlink(inode, proc_ino->i_nlink);
- inode->i_size = proc_ino->i_size;
- inode->i_blocks = proc_ino->i_blocks;
-
- return inode;
-}
-
-static int hppfs_fill_super(struct super_block *sb, void *d, int silent)
-{
- struct inode *root_inode;
- struct vfsmount *proc_mnt;
- int err = -ENOENT;
-
- proc_mnt = mntget(task_active_pid_ns(current)->proc_mnt);
- if (IS_ERR(proc_mnt))
- goto out;
-
- sb->s_blocksize = 1024;
- sb->s_blocksize_bits = 10;
- sb->s_magic = HPPFS_SUPER_MAGIC;
- sb->s_op = &hppfs_sbops;
- sb->s_fs_info = proc_mnt;
-
- err = -ENOMEM;
- root_inode = get_inode(sb, dget(proc_mnt->mnt_root));
- sb->s_root = d_make_root(root_inode);
- if (!sb->s_root)
- goto out_mntput;
-
- return 0;
-
- out_mntput:
- mntput(proc_mnt);
- out:
- return(err);
-}
-
-static struct dentry *hppfs_read_super(struct file_system_type *type,
- int flags, const char *dev_name,
- void *data)
-{
- return mount_nodev(type, flags, data, hppfs_fill_super);
-}
-
-static struct file_system_type hppfs_type = {
- .owner = THIS_MODULE,
- .name = "hppfs",
- .mount = hppfs_read_super,
- .kill_sb = kill_anon_super,
- .fs_flags = 0,
-};
-MODULE_ALIAS_FS("hppfs");
-
-static int __init init_hppfs(void)
-{
- return register_filesystem(&hppfs_type);
-}
-
-static void __exit exit_hppfs(void)
-{
- unregister_filesystem(&hppfs_type);
-}
-
-module_init(init_hppfs)
-module_exit(exit_hppfs)
-MODULE_LICENSE("GPL");
Code Review / kvmfornfv.git / blobdiff