diff -urpN -X dontdiff linux-2.6.0-test1/fs/Kconfig linux-2.6.0-test1-relayfs-printk/fs/Kconfig
--- linux-2.6.0-test1/fs/Kconfig Sun Jul 13 22:34:42 2003
+++ linux-2.6.0-test1-relayfs-printk/fs/Kconfig Sun Jul 13 22:32:38 2003
@@ -1221,7 +1221,25 @@ config SYSV_FS
If you haven't heard about all of this before, it's safe to say N.
+config RELAYFS_FS
+ tristate "Relayfs file system support"
+ ---help---
+ Relayfs is a high-speed data relay filesystem designed to provide
+ an efficient mechanism for tools and facilities to relay large
+ amounts of data from kernel space to user space. It's not useful
+ on its own, and should only be enabled if other facilities that
+ need it are enabled, such as for example dynamic printk or the
+ Linux Trace Toolkit.
+ See <file:Documentation/filesystems/relayfs.txt> for further
+ information.
+
+ This file system is also available as a module ( = code which can be
+ inserted in and removed from the running kernel whenever you want).
+ The module is called relayfs.ko. If you want to compile it as a
+ module, say M here and read <file:Documentation/modules.txt>.
+
+ If unsure, say N.
config UFS_FS
tristate "UFS file system support (read only)"
diff -urpN -X dontdiff linux-2.6.0-test1/fs/Makefile linux-2.6.0-test1-relayfs-printk/fs/Makefile
--- linux-2.6.0-test1/fs/Makefile Sun Jul 13 22:34:42 2003
+++ linux-2.6.0-test1-relayfs-printk/fs/Makefile Sun Jul 13 22:32:38 2003
@@ -67,6 +67,7 @@ obj-$(CONFIG_ISO9660_FS) += isofs/
obj-$(CONFIG_DEVFS_FS) += devfs/
obj-$(CONFIG_HFS_FS) += hfs/
obj-$(CONFIG_VXFS_FS) += freevxfs/
+obj-$(CONFIG_RELAYFS_FS) += relayfs/
obj-$(CONFIG_NFS_FS) += nfs/
obj-$(CONFIG_EXPORTFS) += exportfs/
obj-$(CONFIG_NFSD) += nfsd/
diff -urpN -X dontdiff linux-2.6.0-test1/fs/relayfs/Makefile linux-2.6.0-test1-relayfs-printk/fs/relayfs/Makefile
--- linux-2.6.0-test1/fs/relayfs/Makefile Wed Dec 31 18:00:00 1969
+++ linux-2.6.0-test1-relayfs-printk/fs/relayfs/Makefile Sun Jul 13 22:32:38 2003
@@ -0,0 +1,7 @@
+#
+# relayfs Makefile
+#
+
+obj-$(CONFIG_RELAYFS_FS) += relayfs.o
+
+relayfs-objs := relay.o relay_lockless.o relay_locking.o inode.o
diff -urpN -X dontdiff linux-2.6.0-test1/fs/relayfs/inode.c linux-2.6.0-test1-relayfs-printk/fs/relayfs/inode.c
--- linux-2.6.0-test1/fs/relayfs/inode.c Wed Dec 31 18:00:00 1969
+++ linux-2.6.0-test1-relayfs-printk/fs/relayfs/inode.c Sun Jul 13 22:32:38 2003
@@ -0,0 +1,487 @@
+/*
+ * VFS-related code for RelayFS, a high-speed data relay filesystem.
+ *
+ * Copyright (C) 2003 - Tom Zanussi <[email protected]>, IBM Corp
+ * Copyright (C) 2003 - Karim Yaghmour <[email protected]>
+ *
+ * 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/highmem.h>
+#include <linux/init.h>
+#include <linux/string.h>
+#include <linux/smp_lock.h>
+#include <linux/backing-dev.h>
+#include <linux/namei.h>
+#include <asm/uaccess.h>
+#include <asm/relay.h>
+
+#define RELAYFS_MAGIC 0x26F82121
+
+static struct super_operations relayfs_ops;
+static struct address_space_operations relayfs_aops;
+static struct inode_operations relayfs_file_inode_operations;
+static struct file_operations relayfs_file_operations;
+static struct inode_operations relayfs_dir_inode_operations;
+
+static struct vfsmount * relayfs_mount;
+
+static struct backing_dev_info relayfs_backing_dev_info = {
+ .ra_pages = 0, /* No readahead */
+ .memory_backed = 1, /* Does not contribute to dirty memory */
+};
+
+static struct inode *
+relayfs_get_inode(struct super_block *sb, int mode, dev_t dev)
+{
+ struct inode * inode = new_inode(sb);
+
+ if (inode) {
+ inode->i_mode = mode;
+ inode->i_uid = current->fsuid;
+ inode->i_gid = current->fsgid;
+ inode->i_blksize = PAGE_CACHE_SIZE;
+ inode->i_blocks = 0;
+ inode->i_rdev = NODEV;
+ inode->i_mapping->a_ops = &relayfs_aops;
+ 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) {
+ default:
+ init_special_inode(inode, mode, dev);
+ break;
+ case S_IFREG:
+ inode->i_op = &relayfs_file_inode_operations;
+ inode->i_fop = &relayfs_file_operations;
+ break;
+ case S_IFDIR:
+ inode->i_op = &relayfs_dir_inode_operations;
+ inode->i_fop = &simple_dir_operations;
+
+ /* directory inodes start off with i_nlink == 2 (for "." entry) */
+ inode->i_nlink++;
+ break;
+ case S_IFLNK:
+ inode->i_op = &page_symlink_inode_operations;
+ break;
+ }
+ }
+ return inode;
+}
+
+/*
+ * File creation. Allocate an inode, and we're done..
+ */
+/* SMP-safe */
+static int
+relayfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
+{
+ struct inode * inode = relayfs_get_inode(dir->i_sb, mode, dev);
+ int error = -ENOSPC;
+
+ if (inode) {
+ d_instantiate(dentry, inode);
+ dget(dentry); /* Extra count - pin the dentry in core */
+ error = 0;
+ }
+ return error;
+}
+
+static int
+relayfs_mkdir(struct inode * dir, struct dentry * dentry, int mode)
+{
+ int retval = relayfs_mknod(dir, dentry, mode | S_IFDIR, 0);
+
+ if (!retval)
+ dir->i_nlink++;
+ return retval;
+}
+
+static int
+relayfs_create(struct inode *dir, struct dentry *dentry, int mode, struct nameidata *nd)
+{
+
+ return relayfs_mknod(dir, dentry, mode | S_IFREG, 0);
+}
+
+static int
+relayfs_symlink(struct inode * dir, struct dentry *dentry, const char * symname)
+{
+ struct inode *inode;
+ int error = -ENOSPC;
+
+ inode = relayfs_get_inode(dir->i_sb, S_IFLNK|S_IRWXUGO, 0);
+
+ if (inode) {
+ int l = strlen(symname)+1;
+ error = page_symlink(inode, symname, l);
+ if (!error) {
+ d_instantiate(dentry, inode);
+ dget(dentry);
+ } else
+ iput(inode);
+ }
+ return error;
+}
+
+/**
+ * relayfs_create_entry - create a relayfs directory or file
+ * @name: the name of the file to create
+ * @parent: parent directory
+ * @dentry: result dentry
+ * @entry_type: type of file to create (S_IFREG, S_IFDIR)
+ * @mode: mode
+ * @data: data to associate with the file
+ *
+ * Creates a file or directory with the specifed permissions.
+ */
+static int
+relayfs_create_entry(const char * name, struct dentry * parent, struct dentry **dentry, int entry_type, int mode, void * data)
+{
+ struct qstr qname;
+ struct dentry * d;
+
+ int error = 0;
+
+ qname.name = name;
+ qname.len = strlen(name);
+ qname.hash = full_name_hash(name, qname.len);
+
+ if (parent == NULL)
+ if (relayfs_mount && relayfs_mount->mnt_sb)
+ parent = relayfs_mount->mnt_sb->s_root;
+
+ if (parent == NULL)
+ return -EINVAL;
+
+ parent = dget(parent);
+ down(&parent->d_inode->i_sem);
+ d = lookup_hash(&qname, parent);
+ if (IS_ERR(d)) {
+ error = PTR_ERR(d);
+ goto exit;
+ }
+
+ if (d->d_inode) {
+ error = -EEXIST;
+ goto exit;
+ }
+
+ if (entry_type == S_IFREG)
+ error = relayfs_create(parent->d_inode, d, entry_type | mode, NULL);
+ else
+ error = relayfs_mkdir(parent->d_inode, d, entry_type | mode);
+
+ if ((entry_type == S_IFREG) && data && !error)
+ d->d_inode->u.generic_ip = data;
+exit:
+ *dentry = d;
+ up(&parent->d_inode->i_sem);
+ dput(parent);
+
+ return error;
+}
+
+/**
+ * relayfs_create_file - create a file in the relay filesystem
+ * @name: the name of the file to create
+ * @parent: parent directory
+ * @dentry: result dentry
+ * @data: data to associate with the file
+ *
+ * The file will be created user rwx on behalf of current user.
+ */
+int
+relayfs_create_file(const char * name, struct dentry * parent, struct dentry **dentry, void * data)
+{
+ return relayfs_create_entry(name, parent, dentry, S_IFREG,
+ S_IRWXU, data);
+}
+
+/**
+ * relayfs_create_dir - create a directory in the relay filesystem
+ * @name: the name of the directory to create
+ * @parent: parent directory
+ * @dentry: result dentry
+ *
+ * The directory will be created world rwx on behalf of current user.
+ */
+int
+relayfs_create_dir(const char * name, struct dentry * parent, struct dentry **dentry)
+{
+ return relayfs_create_entry(name, parent, dentry, S_IFDIR,
+ S_IRWXU | S_IRUGO | S_IXUGO, NULL);
+}
+
+/**
+ * relayfs_remove_file - remove a file in the relay filesystem
+ * @dentry: file dentry
+ *
+ * Remove a file previously created by relayfs_create_file.
+ */
+int
+relayfs_remove_file(struct dentry *dentry)
+{
+ struct dentry *parent;
+
+ parent = dentry->d_parent;
+ if (parent == NULL)
+ return -EINVAL;
+
+ parent = dget(parent);
+ down(&parent->d_inode->i_sem);
+ if (dentry->d_inode) {
+ simple_unlink(parent->d_inode, dentry);
+ d_delete(dentry);
+ }
+ up(&parent->d_inode->i_sem);
+ dput(parent);
+
+ return 0;
+}
+
+/**
+ * relayfs_open - open file op for relayfs files
+ * @inode: the inode
+ * @filp: the file
+ *
+ * Associates the channel with the file, and increments the
+ * channel refcount.
+ */
+int
+relayfs_open(struct inode *inode, struct file *filp)
+{
+ struct rchan *rchan;
+
+ if (inode->u.generic_ip) {
+ filp->private_data = inode->u.generic_ip;
+ rchan = (struct rchan *)inode->u.generic_ip;
+ /* Inc relay channel refcount for file */
+ rchan_get(rchan->id);
+ }
+
+ return 0;
+}
+
+/**
+ * relayfs_mmap - mmap file op for relayfs files
+ * @filp: the file
+ * @vma: the vma describing what to map
+ *
+ * Calls upon relay_mmap_buffer to map the file into user space.
+ */
+int
+relayfs_mmap(struct file *filp, struct vm_area_struct *vma)
+{
+ struct rchan *rchan = (struct rchan *)filp->private_data;
+
+ return relay_mmap_buffer(rchan->id, vma);
+}
+
+/**
+ * relayfs_file_read - read file op for relayfs files
+ * @filp: the file
+ * @buf: user buf to read into
+ * @count: bytes requested
+ * @offset: offset into file
+ *
+ * Attempt to read count bytes into buffer. If there are fewer
+ * than count bytes available, return available. if the read would
+ * cross a sub-buffer boundary, this function will only return the
+ * bytes available to the end of the sub-buffer; a subsequent read
+ * would get the remaining bytes (starting from the beginning of the
+ * buffer). Because we're reading from a circular buffer, if the
+ * read would wrap around to sub-buffer 0, offset will be reset
+ * to 0 to mark the beginning of the buffer. If nothing at all
+ * is available, the caller will be put on a wait queue until
+ * there is. This function takes into account the 'unused bytes',
+ * if any, at the end of each sub-buffer, and will transparently
+ * skip over them.
+ */
+ssize_t
+relayfs_file_read(struct file *filp, char * buf, size_t count, loff_t *offset)
+{
+ u32 new_offset;
+ size_t read_count;
+
+ struct rchan *rchan = (struct rchan *)filp->private_data;
+
+ read_count = relay_read(rchan->id, buf, count, (u32)*offset, &new_offset, 1);
+ *offset = (loff_t)new_offset;
+
+ return read_count;
+}
+
+/**
+ * relayfs_file_write - write file op for relayfs files
+ * @filp: the file
+ * @buf: user buf to write from
+ * @count: bytes to write
+ * @offset: offset into file
+ *
+ * Reserves a slot in the relay buffer and writes count bytes
+ * into it. The current limit for a single write is 2 pages
+ * worth.
+ */
+ssize_t
+relayfs_file_write(struct file *filp, const char *buf, size_t count, loff_t *offset)
+{
+ int bytes_written;
+ char * write_buf;
+
+ struct rchan *rchan = (struct rchan *)filp->private_data;
+
+ /* Change this if need to write more than 2 pages at once */
+ if (count > 2 * PAGE_SIZE)
+ return -EINVAL;
+
+ write_buf = (char *)__get_free_pages(GFP_KERNEL, 1);
+ if (write_buf == NULL)
+ return -ENOMEM;
+
+ if (copy_from_user(write_buf, buf, count))
+ return -EFAULT;
+
+
+ bytes_written = relay_write(rchan->id, write_buf, count, -1);
+ if (bytes_written > 0)
+ *offset += bytes_written;
+
+ free_pages((unsigned long)write_buf, 1);
+
+ return bytes_written;
+}
+
+/**
+ * relayfs_release - release file op for relayfs files
+ * @inode: the inode
+ * @filp: the file
+ *
+ * Decrements the channel refcount, as the filesystem is
+ * no longer using it.
+ */
+int
+relayfs_release(struct inode *inode, struct file *filp)
+{
+ int err = 0;
+
+ struct rchan *rchan = (struct rchan *)filp->private_data;
+
+ /* The channel is no longer in use as far as this file is concerned */
+ rchan_put(rchan);
+
+ return err;
+}
+
+static struct address_space_operations relayfs_aops = {
+ .readpage = simple_readpage,
+ .prepare_write = simple_prepare_write,
+ .commit_write = simple_commit_write
+};
+
+static struct file_operations relayfs_file_operations = {
+ .open = relayfs_open,
+ .read = relayfs_file_read,
+ .write = relayfs_file_write,
+ .mmap = relayfs_mmap,
+ .fsync = simple_sync_file,
+ .release = relayfs_release,
+};
+
+static struct inode_operations relayfs_file_inode_operations = {
+ .getattr = simple_getattr,
+};
+
+static struct inode_operations relayfs_dir_inode_operations = {
+ .create = relayfs_create,
+ .lookup = simple_lookup,
+ .link = simple_link,
+ .unlink = simple_unlink,
+ .symlink = relayfs_symlink,
+ .mkdir = relayfs_mkdir,
+ .rmdir = simple_rmdir,
+ .mknod = relayfs_mknod,
+ .rename = simple_rename,
+};
+
+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;
+
+ 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, S_IFDIR | 0755, 0);
+
+ 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)
+{
+ int err;
+
+ err = register_filesystem(&relayfs_fs_type);
+ if (!err) {
+ relayfs_mount = kern_mount(&relayfs_fs_type);
+ if (IS_ERR(relayfs_mount)) {
+ err = PTR_ERR(relayfs_mount);
+ printk(KERN_ERR "Couldn't mount relayfs: errcode %d\n", err);
+ relayfs_mount = NULL;
+ }
+ }
+
+ return err;
+}
+
+static void __exit
+exit_relayfs_fs(void)
+{
+ unregister_filesystem(&relayfs_fs_type);
+}
+
+module_init(init_relayfs_fs)
+module_exit(exit_relayfs_fs)
+
+MODULE_AUTHOR("Tom Zanussi <[email protected]> and Karim Yaghmour <[email protected]>");
+MODULE_DESCRIPTION("Relay Filesystem");
+MODULE_LICENSE("GPL");
+
--
Regards,
Tom Zanussi <[email protected]>
IBM Linux Technology Center/RAS