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-rw-r--r--fs/relayfs/inode.c581
1 files changed, 0 insertions, 581 deletions
diff --git a/fs/relayfs/inode.c b/fs/relayfs/inode.c
deleted file mode 100644
index 3835230..0000000
--- a/fs/relayfs/inode.c
+++ /dev/null
@@ -1,581 +0,0 @@
-/*
- * VFS-related code for RelayFS, a high-speed data relay filesystem.
- *
- * Copyright (C) 2003-2005 - Tom Zanussi <zanussi@us.ibm.com>, IBM Corp
- * Copyright (C) 2003-2005 - Karim Yaghmour <karim@opersys.com>
- *
- * Based on ramfs, Copyright (C) 2002 - Linus Torvalds
- *
- * This file is released under the GPL.
- */
-
-#include <linux/module.h>
-#include <linux/fs.h>
-#include <linux/mount.h>
-#include <linux/pagemap.h>
-#include <linux/init.h>
-#include <linux/string.h>
-#include <linux/backing-dev.h>
-#include <linux/namei.h>
-#include <linux/poll.h>
-#include <linux/relayfs_fs.h>
-#include "relay.h"
-#include "buffers.h"
-
-#define RELAYFS_MAGIC 0xF0B4A981
-
-static struct vfsmount * relayfs_mount;
-static int relayfs_mount_count;
-
-static struct backing_dev_info relayfs_backing_dev_info = {
- .ra_pages = 0, /* No readahead */
- .capabilities = BDI_CAP_NO_ACCT_DIRTY | BDI_CAP_NO_WRITEBACK,
-};
-
-static struct inode *relayfs_get_inode(struct super_block *sb,
- int mode,
- struct file_operations *fops,
- void *data)
-{
- struct inode *inode;
-
- inode = new_inode(sb);
- if (!inode)
- return NULL;
-
- inode->i_mode = mode;
- inode->i_uid = 0;
- inode->i_gid = 0;
- inode->i_blksize = PAGE_CACHE_SIZE;
- inode->i_blocks = 0;
- inode->i_mapping->backing_dev_info = &relayfs_backing_dev_info;
- inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
- switch (mode & S_IFMT) {
- case S_IFREG:
- inode->i_fop = fops;
- if (data)
- inode->u.generic_ip = data;
- break;
- case S_IFDIR:
- inode->i_op = &simple_dir_inode_operations;
- inode->i_fop = &simple_dir_operations;
-
- /* directory inodes start off with i_nlink == 2 (for "." entry) */
- inode->i_nlink++;
- break;
- default:
- break;
- }
-
- return inode;
-}
-
-/**
- * relayfs_create_entry - create a relayfs directory or file
- * @name: the name of the file to create
- * @parent: parent directory
- * @mode: mode
- * @fops: file operations to use for the file
- * @data: user-associated data for this file
- *
- * Returns the new dentry, NULL on failure
- *
- * Creates a file or directory with the specifed permissions.
- */
-static struct dentry *relayfs_create_entry(const char *name,
- struct dentry *parent,
- int mode,
- struct file_operations *fops,
- void *data)
-{
- struct dentry *d;
- struct inode *inode;
- int error = 0;
-
- BUG_ON(!name || !(S_ISREG(mode) || S_ISDIR(mode)));
-
- error = simple_pin_fs("relayfs", &relayfs_mount, &relayfs_mount_count);
- if (error) {
- printk(KERN_ERR "Couldn't mount relayfs: errcode %d\n", error);
- return NULL;
- }
-
- if (!parent && relayfs_mount && relayfs_mount->mnt_sb)
- parent = relayfs_mount->mnt_sb->s_root;
-
- if (!parent) {
- simple_release_fs(&relayfs_mount, &relayfs_mount_count);
- return NULL;
- }
-
- parent = dget(parent);
- mutex_lock(&parent->d_inode->i_mutex);
- d = lookup_one_len(name, parent, strlen(name));
- if (IS_ERR(d)) {
- d = NULL;
- goto release_mount;
- }
-
- if (d->d_inode) {
- d = NULL;
- goto release_mount;
- }
-
- inode = relayfs_get_inode(parent->d_inode->i_sb, mode, fops, data);
- if (!inode) {
- d = NULL;
- goto release_mount;
- }
-
- d_instantiate(d, inode);
- dget(d); /* Extra count - pin the dentry in core */
-
- if (S_ISDIR(mode))
- parent->d_inode->i_nlink++;
-
- goto exit;
-
-release_mount:
- simple_release_fs(&relayfs_mount, &relayfs_mount_count);
-
-exit:
- mutex_unlock(&parent->d_inode->i_mutex);
- dput(parent);
- return d;
-}
-
-/**
- * relayfs_create_file - create a file in the relay filesystem
- * @name: the name of the file to create
- * @parent: parent directory
- * @mode: mode, if not specied the default perms are used
- * @fops: file operations to use for the file
- * @data: user-associated data for this file
- *
- * Returns file dentry if successful, NULL otherwise.
- *
- * The file will be created user r on behalf of current user.
- */
-struct dentry *relayfs_create_file(const char *name,
- struct dentry *parent,
- int mode,
- struct file_operations *fops,
- void *data)
-{
- BUG_ON(!fops);
-
- if (!mode)
- mode = S_IRUSR;
- mode = (mode & S_IALLUGO) | S_IFREG;
-
- return relayfs_create_entry(name, parent, mode, fops, data);
-}
-
-/**
- * relayfs_create_dir - create a directory in the relay filesystem
- * @name: the name of the directory to create
- * @parent: parent directory, NULL if parent should be fs root
- *
- * Returns directory dentry if successful, NULL otherwise.
- *
- * The directory will be created world rwx on behalf of current user.
- */
-struct dentry *relayfs_create_dir(const char *name, struct dentry *parent)
-{
- int mode = S_IFDIR | S_IRWXU | S_IRUGO | S_IXUGO;
- return relayfs_create_entry(name, parent, mode, NULL, NULL);
-}
-
-/**
- * relayfs_remove - remove a file or directory in the relay filesystem
- * @dentry: file or directory dentry
- *
- * Returns 0 if successful, negative otherwise.
- */
-int relayfs_remove(struct dentry *dentry)
-{
- struct dentry *parent;
- int error = 0;
-
- if (!dentry)
- return -EINVAL;
- parent = dentry->d_parent;
- if (!parent)
- return -EINVAL;
-
- parent = dget(parent);
- mutex_lock(&parent->d_inode->i_mutex);
- if (dentry->d_inode) {
- if (S_ISDIR(dentry->d_inode->i_mode))
- error = simple_rmdir(parent->d_inode, dentry);
- else
- error = simple_unlink(parent->d_inode, dentry);
- if (!error)
- d_delete(dentry);
- }
- if (!error)
- dput(dentry);
- mutex_unlock(&parent->d_inode->i_mutex);
- dput(parent);
-
- if (!error)
- simple_release_fs(&relayfs_mount, &relayfs_mount_count);
-
- return error;
-}
-
-/**
- * relayfs_remove_file - remove a file from relay filesystem
- * @dentry: directory dentry
- *
- * Returns 0 if successful, negative otherwise.
- */
-int relayfs_remove_file(struct dentry *dentry)
-{
- return relayfs_remove(dentry);
-}
-
-/**
- * relayfs_remove_dir - remove a directory in the relay filesystem
- * @dentry: directory dentry
- *
- * Returns 0 if successful, negative otherwise.
- */
-int relayfs_remove_dir(struct dentry *dentry)
-{
- return relayfs_remove(dentry);
-}
-
-/**
- * relay_file_open - open file op for relay files
- * @inode: the inode
- * @filp: the file
- *
- * Increments the channel buffer refcount.
- */
-static int relay_file_open(struct inode *inode, struct file *filp)
-{
- struct rchan_buf *buf = inode->u.generic_ip;
- kref_get(&buf->kref);
- filp->private_data = buf;
-
- return 0;
-}
-
-/**
- * relay_file_mmap - mmap file op for relay files
- * @filp: the file
- * @vma: the vma describing what to map
- *
- * Calls upon relay_mmap_buf to map the file into user space.
- */
-static int relay_file_mmap(struct file *filp, struct vm_area_struct *vma)
-{
- struct rchan_buf *buf = filp->private_data;
- return relay_mmap_buf(buf, vma);
-}
-
-/**
- * relay_file_poll - poll file op for relay files
- * @filp: the file
- * @wait: poll table
- *
- * Poll implemention.
- */
-static unsigned int relay_file_poll(struct file *filp, poll_table *wait)
-{
- unsigned int mask = 0;
- struct rchan_buf *buf = filp->private_data;
-
- if (buf->finalized)
- return POLLERR;
-
- if (filp->f_mode & FMODE_READ) {
- poll_wait(filp, &buf->read_wait, wait);
- if (!relay_buf_empty(buf))
- mask |= POLLIN | POLLRDNORM;
- }
-
- return mask;
-}
-
-/**
- * relay_file_release - release file op for relay files
- * @inode: the inode
- * @filp: the file
- *
- * Decrements the channel refcount, as the filesystem is
- * no longer using it.
- */
-static int relay_file_release(struct inode *inode, struct file *filp)
-{
- struct rchan_buf *buf = filp->private_data;
- kref_put(&buf->kref, relay_remove_buf);
-
- return 0;
-}
-
-/**
- * relay_file_read_consume - update the consumed count for the buffer
- */
-static void relay_file_read_consume(struct rchan_buf *buf,
- size_t read_pos,
- size_t bytes_consumed)
-{
- size_t subbuf_size = buf->chan->subbuf_size;
- size_t n_subbufs = buf->chan->n_subbufs;
- size_t read_subbuf;
-
- if (buf->bytes_consumed + bytes_consumed > subbuf_size) {
- relay_subbufs_consumed(buf->chan, buf->cpu, 1);
- buf->bytes_consumed = 0;
- }
-
- buf->bytes_consumed += bytes_consumed;
- read_subbuf = read_pos / buf->chan->subbuf_size;
- if (buf->bytes_consumed + buf->padding[read_subbuf] == subbuf_size) {
- if ((read_subbuf == buf->subbufs_produced % n_subbufs) &&
- (buf->offset == subbuf_size))
- return;
- relay_subbufs_consumed(buf->chan, buf->cpu, 1);
- buf->bytes_consumed = 0;
- }
-}
-
-/**
- * relay_file_read_avail - boolean, are there unconsumed bytes available?
- */
-static int relay_file_read_avail(struct rchan_buf *buf, size_t read_pos)
-{
- size_t bytes_produced, bytes_consumed, write_offset;
- size_t subbuf_size = buf->chan->subbuf_size;
- size_t n_subbufs = buf->chan->n_subbufs;
- size_t produced = buf->subbufs_produced % n_subbufs;
- size_t consumed = buf->subbufs_consumed % n_subbufs;
-
- write_offset = buf->offset > subbuf_size ? subbuf_size : buf->offset;
-
- if (consumed > produced) {
- if ((produced > n_subbufs) &&
- (produced + n_subbufs - consumed <= n_subbufs))
- produced += n_subbufs;
- } else if (consumed == produced) {
- if (buf->offset > subbuf_size) {
- produced += n_subbufs;
- if (buf->subbufs_produced == buf->subbufs_consumed)
- consumed += n_subbufs;
- }
- }
-
- if (buf->offset > subbuf_size)
- bytes_produced = (produced - 1) * subbuf_size + write_offset;
- else
- bytes_produced = produced * subbuf_size + write_offset;
- bytes_consumed = consumed * subbuf_size + buf->bytes_consumed;
-
- if (bytes_produced == bytes_consumed)
- return 0;
-
- relay_file_read_consume(buf, read_pos, 0);
-
- return 1;
-}
-
-/**
- * relay_file_read_subbuf_avail - return bytes available in sub-buffer
- */
-static size_t relay_file_read_subbuf_avail(size_t read_pos,
- struct rchan_buf *buf)
-{
- size_t padding, avail = 0;
- size_t read_subbuf, read_offset, write_subbuf, write_offset;
- size_t subbuf_size = buf->chan->subbuf_size;
-
- write_subbuf = (buf->data - buf->start) / subbuf_size;
- write_offset = buf->offset > subbuf_size ? subbuf_size : buf->offset;
- read_subbuf = read_pos / subbuf_size;
- read_offset = read_pos % subbuf_size;
- padding = buf->padding[read_subbuf];
-
- if (read_subbuf == write_subbuf) {
- if (read_offset + padding < write_offset)
- avail = write_offset - (read_offset + padding);
- } else
- avail = (subbuf_size - padding) - read_offset;
-
- return avail;
-}
-
-/**
- * relay_file_read_start_pos - find the first available byte to read
- *
- * If the read_pos is in the middle of padding, return the
- * position of the first actually available byte, otherwise
- * return the original value.
- */
-static size_t relay_file_read_start_pos(size_t read_pos,
- struct rchan_buf *buf)
-{
- size_t read_subbuf, padding, padding_start, padding_end;
- size_t subbuf_size = buf->chan->subbuf_size;
- size_t n_subbufs = buf->chan->n_subbufs;
-
- read_subbuf = read_pos / subbuf_size;
- padding = buf->padding[read_subbuf];
- padding_start = (read_subbuf + 1) * subbuf_size - padding;
- padding_end = (read_subbuf + 1) * subbuf_size;
- if (read_pos >= padding_start && read_pos < padding_end) {
- read_subbuf = (read_subbuf + 1) % n_subbufs;
- read_pos = read_subbuf * subbuf_size;
- }
-
- return read_pos;
-}
-
-/**
- * relay_file_read_end_pos - return the new read position
- */
-static size_t relay_file_read_end_pos(struct rchan_buf *buf,
- size_t read_pos,
- size_t count)
-{
- size_t read_subbuf, padding, end_pos;
- size_t subbuf_size = buf->chan->subbuf_size;
- size_t n_subbufs = buf->chan->n_subbufs;
-
- read_subbuf = read_pos / subbuf_size;
- padding = buf->padding[read_subbuf];
- if (read_pos % subbuf_size + count + padding == subbuf_size)
- end_pos = (read_subbuf + 1) * subbuf_size;
- else
- end_pos = read_pos + count;
- if (end_pos >= subbuf_size * n_subbufs)
- end_pos = 0;
-
- return end_pos;
-}
-
-/**
- * relay_file_read - read file op for relay files
- * @filp: the file
- * @buffer: the userspace buffer
- * @count: number of bytes to read
- * @ppos: position to read from
- *
- * Reads count bytes or the number of bytes available in the
- * current sub-buffer being read, whichever is smaller.
- */
-static ssize_t relay_file_read(struct file *filp,
- char __user *buffer,
- size_t count,
- loff_t *ppos)
-{
- struct rchan_buf *buf = filp->private_data;
- struct inode *inode = filp->f_dentry->d_inode;
- size_t read_start, avail;
- ssize_t ret = 0;
- void *from;
-
- mutex_lock(&inode->i_mutex);
- if(!relay_file_read_avail(buf, *ppos))
- goto out;
-
- read_start = relay_file_read_start_pos(*ppos, buf);
- avail = relay_file_read_subbuf_avail(read_start, buf);
- if (!avail)
- goto out;
-
- from = buf->start + read_start;
- ret = count = min(count, avail);
- if (copy_to_user(buffer, from, count)) {
- ret = -EFAULT;
- goto out;
- }
- relay_file_read_consume(buf, read_start, count);
- *ppos = relay_file_read_end_pos(buf, read_start, count);
-out:
- mutex_unlock(&inode->i_mutex);
- return ret;
-}
-
-struct file_operations relay_file_operations = {
- .open = relay_file_open,
- .poll = relay_file_poll,
- .mmap = relay_file_mmap,
- .read = relay_file_read,
- .llseek = no_llseek,
- .release = relay_file_release,
-};
-
-static struct super_operations relayfs_ops = {
- .statfs = simple_statfs,
- .drop_inode = generic_delete_inode,
-};
-
-static int relayfs_fill_super(struct super_block * sb, void * data, int silent)
-{
- struct inode *inode;
- struct dentry *root;
- int mode = S_IFDIR | S_IRWXU | S_IRUGO | S_IXUGO;
-
- sb->s_blocksize = PAGE_CACHE_SIZE;
- sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
- sb->s_magic = RELAYFS_MAGIC;
- sb->s_op = &relayfs_ops;
- inode = relayfs_get_inode(sb, mode, NULL, NULL);
-
- if (!inode)
- return -ENOMEM;
-
- root = d_alloc_root(inode);
- if (!root) {
- iput(inode);
- return -ENOMEM;
- }
- sb->s_root = root;
-
- return 0;
-}
-
-static struct super_block * relayfs_get_sb(struct file_system_type *fs_type,
- int flags, const char *dev_name,
- void *data)
-{
- return get_sb_single(fs_type, flags, data, relayfs_fill_super);
-}
-
-static struct file_system_type relayfs_fs_type = {
- .owner = THIS_MODULE,
- .name = "relayfs",
- .get_sb = relayfs_get_sb,
- .kill_sb = kill_litter_super,
-};
-
-static int __init init_relayfs_fs(void)
-{
- return register_filesystem(&relayfs_fs_type);
-}
-
-static void __exit exit_relayfs_fs(void)
-{
-
-
-
-
-
- unregister_filesystem(&relayfs_fs_type);
-}
-
-module_init(init_relayfs_fs)
-module_exit(exit_relayfs_fs)
-
-EXPORT_SYMBOL_GPL(relay_file_operations);
-EXPORT_SYMBOL_GPL(relayfs_create_dir);
-EXPORT_SYMBOL_GPL(relayfs_remove_dir);
-EXPORT_SYMBOL_GPL(relayfs_create_file);
-EXPORT_SYMBOL_GPL(relayfs_remove_file);
-
-MODULE_AUTHOR("Tom Zanussi <zanussi@us.ibm.com> and Karim Yaghmour <karim@opersys.com>");
-MODULE_DESCRIPTION("Relay Filesystem");
-MODULE_LICENSE("GPL");
-
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