diff options
Diffstat (limited to 'fs/hppfs/hppfs_kern.c')
| -rw-r--r-- | fs/hppfs/hppfs_kern.c | 815 |
1 files changed, 815 insertions, 0 deletions
diff --git a/fs/hppfs/hppfs_kern.c b/fs/hppfs/hppfs_kern.c new file mode 100644 index 000000000000..f8e0cbd0cb60 --- /dev/null +++ b/fs/hppfs/hppfs_kern.c @@ -0,0 +1,815 @@ +/* + * Copyright (C) 2002 Jeff Dike (jdike@karaya.com) + * Licensed under the GPL + */ + +#include <linux/fs.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/slab.h> +#include <linux/list.h> +#include <linux/kernel.h> +#include <linux/ctype.h> +#include <linux/dcache.h> +#include <linux/statfs.h> +#include <asm/uaccess.h> +#include <asm/fcntl.h> +#include "os.h" + +static int init_inode(struct inode *inode, struct dentry *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(list_entry(inode, struct hppfs_inode_info, vfs_inode)); +} + +#define HPPFS_SUPER_MAGIC 0xb00000ee + +static struct super_operations hppfs_sbops; + +static int is_pid(struct dentry *dentry) +{ + struct super_block *sb; + int i; + + sb = dentry->d_sb; + if((sb->s_op != &hppfs_sbops) || (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; + + 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"; + len += strlen(root); + 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("pid"); + } + else { + seg_name = parent->d_name.name; + seg_len = parent->d_name.len; + } + + len -= seg_len + 1; + name[len] = '/'; + strncpy(&name[len + 1], seg_name, seg_len); + parent = parent->d_parent; + } + strncpy(name, root, strlen(root)); + return(name); +} + +struct dentry_operations hppfs_dentry_ops = { +}; + +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("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 void hppfs_read_inode(struct inode *ino) +{ + struct inode *proc_ino; + + if(HPPFS_I(ino)->proc_dentry == NULL) + return; + + proc_ino = HPPFS_I(ino)->proc_dentry->d_inode; + ino->i_uid = proc_ino->i_uid; + ino->i_gid = proc_ino->i_gid; + ino->i_atime = proc_ino->i_atime; + ino->i_mtime = proc_ino->i_mtime; + ino->i_ctime = proc_ino->i_ctime; + ino->i_ino = proc_ino->i_ino; + ino->i_mode = proc_ino->i_mode; + ino->i_nlink = proc_ino->i_nlink; + ino->i_size = proc_ino->i_size; + ino->i_blksize = proc_ino->i_blksize; + ino->i_blocks = proc_ino->i_blocks; +} + +static struct dentry *hppfs_lookup(struct inode *ino, struct dentry *dentry, + struct nameidata *nd) +{ + struct dentry *proc_dentry, *new, *parent; + 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)); + + err = -ENOMEM; + parent = HPPFS_I(ino)->proc_dentry; + down(&parent->d_inode->i_sem); + proc_dentry = d_lookup(parent, &dentry->d_name); + if(proc_dentry == NULL){ + proc_dentry = d_alloc(parent, &dentry->d_name); + if(proc_dentry == NULL){ + up(&parent->d_inode->i_sem); + goto out; + } + new = (*parent->d_inode->i_op->lookup)(parent->d_inode, + proc_dentry, NULL); + if(new){ + dput(proc_dentry); + proc_dentry = new; + } + } + up(&parent->d_inode->i_sem); + + if(IS_ERR(proc_dentry)) + return(proc_dentry); + + inode = iget(ino->i_sb, 0); + if(inode == NULL) + goto out_dput; + + err = init_inode(inode, proc_dentry); + if(err) + goto out_put; + + hppfs_read_inode(inode); + + d_add(dentry, inode); + dentry->d_op = &hppfs_dentry_ops; + return(NULL); + + out_put: + iput(inode); + out_dput: + dput(proc_dentry); + out: + return(ERR_PTR(err)); +} + +static struct inode_operations hppfs_file_iops = { +}; + +static ssize_t read_proc(struct file *file, char *buf, ssize_t count, + loff_t *ppos, int is_user) +{ + ssize_t (*read)(struct file *, char *, size_t, loff_t *); + ssize_t n; + + read = file->f_dentry->d_inode->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 *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("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("hppfs_read : read failed, errno = %d\n", + count); + 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 *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){ + 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; + copy_to_user(buf, &data->contents[off], count); + *ppos += count; + } + else if(hppfs->host_fd != -1){ + err = os_seek_file(hppfs->host_fd, *ppos); + if(err){ + printk("hppfs_read : seek failed, errno = %d\n", err); + return(err); + } + count = hppfs_read_file(hppfs->host_fd, buf, count); + 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 *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 *, size_t, loff_t *); + int err; + + write = proc_file->f_dentry->d_inode->i_fop->write; + + proc_file->f_pos = file->f_pos; + err = (*write)(proc_file, buf, len, &proc_file->f_pos); + file->f_pos = proc_file->f_pos; + + return(err); +} + +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("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("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("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("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) +{ + struct hppfs_private *data; + struct dentry *proc_dentry; + char *host_file; + int err, fd, type, filter; + + err = -ENOMEM; + data = hppfs_data(); + if(data == NULL) + goto out; + + host_file = dentry_name(file->f_dentry, strlen("/rw")); + if(host_file == NULL) + goto out_free2; + + proc_dentry = HPPFS_I(inode)->proc_dentry; + + /* XXX This isn't closed anywhere */ + data->proc_file = dentry_open(dget(proc_dentry), NULL, + file_mode(file->f_mode)); + 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("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("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) +{ + struct hppfs_private *data; + struct dentry *proc_dentry; + int err; + + err = -ENOMEM; + data = hppfs_data(); + if(data == NULL) + goto out; + + proc_dentry = HPPFS_I(inode)->proc_dentry; + data->proc_file = dentry_open(dget(proc_dentry), NULL, + file_mode(file->f_mode)); + 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 = proc_file->f_dentry->d_inode->i_fop->llseek; + if(llseek != NULL){ + ret = (*llseek)(proc_file, off, where); + if(ret < 0) + return(ret); + } + + return(default_llseek(file, off, where)); +} + +static struct file_operations hppfs_file_fops = { + .owner = NULL, + .llseek = hppfs_llseek, + .read = hppfs_read, + .write = hppfs_write, + .open = hppfs_open, +}; + +struct hppfs_dirent { + void *vfs_dirent; + filldir_t filldir; + struct dentry *dentry; +}; + +static int hppfs_filldir(void *d, const char *name, int size, + loff_t offset, ino_t inode, unsigned int type) +{ + struct hppfs_dirent *dirent = d; + + if(file_removed(dirent->dentry, name)) + return(0); + + return((*dirent->filldir)(dirent->vfs_dirent, name, size, offset, + inode, type)); +} + +static int hppfs_readdir(struct file *file, void *ent, filldir_t filldir) +{ + struct hppfs_private *data = file->private_data; + struct file *proc_file = &data->proc_file; + int (*readdir)(struct file *, void *, filldir_t); + struct hppfs_dirent dirent = ((struct hppfs_dirent) + { .vfs_dirent = ent, + .filldir = filldir, + .dentry = file->f_dentry } ); + int err; + + readdir = proc_file->f_dentry->d_inode->i_fop->readdir; + + proc_file->f_pos = file->f_pos; + err = (*readdir)(proc_file, &dirent, hppfs_filldir); + file->f_pos = proc_file->f_pos; + + return(err); +} + +static int hppfs_fsync(struct file *file, struct dentry *dentry, int datasync) +{ + return(0); +} + +static struct file_operations hppfs_dir_fops = { + .owner = NULL, + .readdir = hppfs_readdir, + .open = hppfs_dir_open, + .fsync = hppfs_fsync, +}; + +static int hppfs_statfs(struct super_block *sb, 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 == NULL) + return(NULL); + + *hi = ((struct hppfs_inode_info) { .proc_dentry = NULL }); + inode_init_once(&hi->vfs_inode); + return(&hi->vfs_inode); +} + +void hppfs_delete_inode(struct inode *ino) +{ + clear_inode(ino); +} + +static void hppfs_destroy_inode(struct inode *inode) +{ + kfree(HPPFS_I(inode)); +} + +static struct super_operations hppfs_sbops = { + .alloc_inode = hppfs_alloc_inode, + .destroy_inode = hppfs_destroy_inode, + .read_inode = hppfs_read_inode, + .delete_inode = hppfs_delete_inode, + .statfs = hppfs_statfs, +}; + +static int hppfs_readlink(struct dentry *dentry, char *buffer, int buflen) +{ + struct file *proc_file; + struct dentry *proc_dentry; + int (*readlink)(struct dentry *, char *, int); + int err, n; + + proc_dentry = HPPFS_I(dentry->d_inode)->proc_dentry; + proc_file = dentry_open(dget(proc_dentry), NULL, O_RDONLY); + err = PTR_ERR(proc_dentry); + if(IS_ERR(proc_dentry)) + return(err); + + readlink = proc_dentry->d_inode->i_op->readlink; + n = (*readlink)(proc_dentry, buffer, buflen); + + fput(proc_file); + + return(n); +} + +static int hppfs_follow_link(struct dentry *dentry, struct nameidata *nd) +{ + struct file *proc_file; + struct dentry *proc_dentry; + int (*follow_link)(struct dentry *, struct nameidata *); + int err, n; + + proc_dentry = HPPFS_I(dentry->d_inode)->proc_dentry; + proc_file = dentry_open(dget(proc_dentry), NULL, O_RDONLY); + err = PTR_ERR(proc_dentry); + if(IS_ERR(proc_dentry)) + return(err); + + follow_link = proc_dentry->d_inode->i_op->follow_link; + n = (*follow_link)(proc_dentry, nd); + + fput(proc_file); + + return(n); +} + +static struct inode_operations hppfs_dir_iops = { + .lookup = hppfs_lookup, +}; + +static struct inode_operations hppfs_link_iops = { + .readlink = hppfs_readlink, + .follow_link = hppfs_follow_link, +}; + +static int init_inode(struct inode *inode, struct dentry *dentry) +{ + if(S_ISDIR(dentry->d_inode->i_mode)){ + inode->i_op = &hppfs_dir_iops; + inode->i_fop = &hppfs_dir_fops; + } + else if(S_ISLNK(dentry->d_inode->i_mode)){ + 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; + + return(0); +} + +static int hppfs_fill_super(struct super_block *sb, void *d, int silent) +{ + struct inode *root_inode; + struct file_system_type *procfs; + struct super_block *proc_sb; + int err; + + err = -ENOENT; + procfs = get_fs_type("proc"); + if(procfs == NULL) + goto out; + + if(list_empty(&procfs->fs_supers)) + goto out; + + proc_sb = list_entry(procfs->fs_supers.next, struct super_block, + s_instances); + + sb->s_blocksize = 1024; + sb->s_blocksize_bits = 10; + sb->s_magic = HPPFS_SUPER_MAGIC; + sb->s_op = &hppfs_sbops; + + root_inode = iget(sb, 0); + if(root_inode == NULL) + goto out; + + err = init_inode(root_inode, proc_sb->s_root); + if(err) + goto out_put; + + err = -ENOMEM; + sb->s_root = d_alloc_root(root_inode); + if(sb->s_root == NULL) + goto out_put; + + hppfs_read_inode(root_inode); + + return(0); + + out_put: + iput(root_inode); + out: + return(err); +} + +static struct super_block *hppfs_read_super(struct file_system_type *type, + int flags, const char *dev_name, + void *data) +{ + return(get_sb_nodev(type, flags, data, hppfs_fill_super)); +} + +static struct file_system_type hppfs_type = { + .owner = THIS_MODULE, + .name = "hppfs", + .get_sb = hppfs_read_super, + .kill_sb = kill_anon_super, + .fs_flags = 0, +}; + +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"); + +/* + * Overrides for Emacs so that we follow Linus's tabbing style. + * Emacs will notice this stuff at the end of the file and automatically + * adjust the settings for this buffer only. This must remain at the end + * of the file. + * --------------------------------------------------------------------------- + * Local variables: + * c-file-style: "linux" + * End: + */ |