From 86dcbf50773b4429e2710f709fa0fb9ebb6dcd3d Mon Sep 17 00:00:00 2001
From: wangdi <wangdi>
Date: Sun, 4 Jan 2004 07:22:40 +0000
Subject: [PATCH] add snapfs to cvs
---
lustre/snapfs/cache.c | 145 +++++
lustre/snapfs/clonefs.c | 596 ++++++++++++++++++
lustre/snapfs/dcache.c | 56 ++
lustre/snapfs/dir.c | 777 ++++++++++++++++++++++++
lustre/snapfs/dotsnap.c | 208 +++++++
lustre/snapfs/file.c | 259 ++++++++
lustre/snapfs/filter.c | 433 ++++++++++++++
lustre/snapfs/inode.c | 211 +++++++
lustre/snapfs/journal_ext3.c | 84 +++
lustre/snapfs/psdev.c | 180 ++++++
lustre/snapfs/snap.c | 278 +++++++++
lustre/snapfs/snaptable.c | 1099 ++++++++++++++++++++++++++++++++++
lustre/snapfs/super.c | 714 ++++++++++++++++++++++
lustre/snapfs/symlink.c | 213 +++++++
lustre/snapfs/sysctl.c | 110 ++++
15 files changed, 5363 insertions(+)
create mode 100644 lustre/snapfs/cache.c
create mode 100644 lustre/snapfs/clonefs.c
create mode 100644 lustre/snapfs/dcache.c
create mode 100644 lustre/snapfs/dir.c
create mode 100644 lustre/snapfs/dotsnap.c
create mode 100644 lustre/snapfs/file.c
create mode 100644 lustre/snapfs/filter.c
create mode 100644 lustre/snapfs/inode.c
create mode 100644 lustre/snapfs/journal_ext3.c
create mode 100644 lustre/snapfs/psdev.c
create mode 100644 lustre/snapfs/snap.c
create mode 100644 lustre/snapfs/snaptable.c
create mode 100644 lustre/snapfs/super.c
create mode 100644 lustre/snapfs/symlink.c
create mode 100644 lustre/snapfs/sysctl.c
diff --git a/lustre/snapfs/cache.c b/lustre/snapfs/cache.c
new file mode 100644
index 0000000000..d0c8f1bb49
--- /dev/null
+++ b/lustre/snapfs/cache.c
@@ -0,0 +1,145 @@
+/*
+ *
+ *
+ * Copyright (C) 2000 Stelias Computing, Inc.
+ * Copyright (C) 2000 Red Hat, Inc.
+ *
+ *
+ */
+
+
+#include <stdarg.h>
+
+#include <asm/bitops.h>
+#include <asm/uaccess.h>
+#include <asm/system.h>
+
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/ext2_fs.h>
+#include <linux/malloc.h>
+#include <linux/vmalloc.h>
+#include <linux/sched.h>
+#include <linux/stat.h>
+#include <linux/string.h>
+#include <linux/locks.h>
+#include <linux/blkdev.h>
+#include <linux/init.h>
+#define __NO_VERSION__
+#include <linux/module.h>
+
+#include <linux/filter.h>
+#include <linux/snapfs.h>
+#include <linux/snapsupport.h>
+
+/*
+ * XXX - Not sure for snapfs that the cache functions are even needed.
+ * Can't all lookups be done by an inode->superblock->u.generic_sbp
+ * lookup?
+ */
+
+/*
+ This file contains the routines associated with managing a
+ cache of files . These caches need to be found
+ fast so they are hashed by the device, with an attempt to have
+ collision chains of length 1.
+*/
+
+/* the intent of this hash is to have collision chains of length 1 */
+#define CACHES_BITS 8
+#define CACHES_SIZE (1 << CACHES_BITS)
+#define CACHES_MASK CACHES_SIZE - 1
+static struct list_head snap_caches[CACHES_SIZE];
+
+static inline int snap_cache_hash(kdev_t dev)
+{
+ return (CACHES_MASK) & ((0x000F & (dev)) + ((0x0F00 & (dev)) >>8));
+}
+
+inline void snap_cache_add(struct snap_cache *cache, kdev_t dev)
+{
+ list_add(&cache->cache_chain,
+ &snap_caches[snap_cache_hash(dev)]);
+ cache->cache_dev = dev;
+}
+
+inline void snap_init_cache_hash(void)
+{
+ int i;
+ for ( i = 0; i < CACHES_SIZE; i++ ) {
+ INIT_LIST_HEAD(&snap_caches[i]);
+ }
+}
+
+/* map a device to a cache */
+struct snap_cache *snap_find_cache(kdev_t dev)
+{
+ struct snap_cache *cache;
+ struct list_head *lh, *tmp;
+
+ lh = tmp = &(snap_caches[snap_cache_hash(dev)]);
+ while ( (tmp = lh->next) != lh ) {
+ cache = list_entry(tmp, struct snap_cache, cache_chain);
+ if ( cache->cache_dev == dev )
+ return cache;
+ }
+ return NULL;
+}
+
+
+/* map an inode to a cache */
+struct snap_cache *snap_get_cache(struct inode *inode)
+{
+ struct snap_cache *cache;
+
+ /* find the correct snap_cache here, based on the device */
+ cache = snap_find_cache(inode->i_dev);
+ if ( !cache ) {
+ printk("WARNING: no cache for dev %d, ino %ld\n",
+ inode->i_dev, inode->i_ino);
+ return NULL;
+ }
+
+ return cache;
+}
+
+
+/* another debugging routine: check fs is InterMezzo fs */
+int snap_ispresto(struct inode *inode)
+{
+ struct snap_cache *cache;
+
+ if ( !inode )
+ return 0;
+ cache = snap_get_cache(inode);
+ if ( !cache )
+ return 0;
+ return (inode->i_dev == cache->cache_dev);
+}
+
+/* setup a cache structure when we need one */
+struct snap_cache *snap_init_cache(void)
+{
+ struct snap_cache *cache;
+
+ /* make a snap_cache structure for the hash */
+ SNAP_ALLOC(cache, struct snap_cache *, sizeof(struct snap_cache));
+ if ( cache ) {
+ memset(cache, 0, sizeof(struct snap_cache));
+ INIT_LIST_HEAD(&cache->cache_chain);
+ INIT_LIST_HEAD(&cache->cache_clone_list);
+ }
+ return cache;
+}
+
+
+/* free a cache structure and all of the memory it is pointing to */
+inline void snap_free_cache(struct snap_cache *cache)
+{
+ if (!cache)
+ return;
+
+
+ SNAP_FREE(cache, sizeof(struct snap_cache));
+}
+
diff --git a/lustre/snapfs/clonefs.c b/lustre/snapfs/clonefs.c
new file mode 100644
index 0000000000..1ef8078076
--- /dev/null
+++ b/lustre/snapfs/clonefs.c
@@ -0,0 +1,596 @@
+/*
+ * Super block/filesystem wide operations
+ *
+ * Copryright (C) 1996 Peter J. Braam <braam@maths.ox.ac.uk> and
+ * Michael Callahan <callahan@maths.ox.ac.uk>
+ *
+ * Rewritten for Linux 2.1. Peter Braam <braam@cs.cmu.edu>
+ * Copyright (C) Carnegie Mellon University
+ *
+ * Copyright (C) 2000, Mountain View Data, Inc, authors
+ * Peter Braam <braam@mountainviewdata.com>,
+ * Harrison Xing <harrisonx@mountainviewdata.com>
+ *
+ */
+
+#define __NO_VERSION__
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/string.h>
+#include <linux/stat.h>
+#include <linux/errno.h>
+#include <linux/locks.h>
+#include <linux/unistd.h>
+
+#include <asm/system.h>
+#include <asm/uaccess.h>
+
+#include <linux/fs.h>
+#include <linux/stat.h>
+#include <linux/errno.h>
+#include <linux/locks.h>
+#include <linux/string.h>
+#include <asm/uaccess.h>
+#include <linux/malloc.h>
+#include <linux/vmalloc.h>
+#include <asm/segment.h>
+
+#include <linux/filter.h>
+#include <linux/snapfs.h>
+#include <linux/snapsupport.h>
+
+/* Clone is a simple file system, read only that just follows redirectors
+ we have placed the entire implementation except clone_read_super in
+ this file
+ */
+
+struct inode_operations clonefs_dir_inode_operations;
+struct inode_operations clonefs_file_inode_operations;
+struct inode_operations clonefs_symlink_inode_operations;
+struct inode_operations clonefs_special_inode_operations;
+struct file_operations clonefs_dir_file_operations;
+struct file_operations clonefs_file_file_operations;
+struct file_operations clonefs_special_file_operations;
+
+/* support routines for following redirectors */
+
+/* Parameter is clonefs inode, 'inode', and typically this may be
+ called before read_inode has completed on this clonefs inode,
+ i.e. we may only assume that i_ino is valid.
+
+ We return an underlying (likely disk) fs inode. This involved
+ handling any redirector inodes found along the way.
+
+ This function is used by all clone fs interface functions to get an
+ underlying fs inode.
+*/
+
+struct inode *clonefs_get_inode(struct inode *inode)
+{
+ struct snap_clone_info *clone_sb;
+ struct inode *cache_inode, *redirected_inode;
+
+ ENTRY;
+
+ /* this only works if snapfs_current does NOT overwrite read_inode */
+ clone_sb = (struct snap_clone_info *) &inode->i_sb->u.generic_sbp;
+
+ /* basic invariant: clone and current ino's are equal */
+ cache_inode = iget(clone_sb->clone_cache->cache_sb, inode->i_ino);
+
+ redirected_inode = snap_redirect(cache_inode, inode->i_sb);
+
+ CDEBUG(D_SNAP, "redirected_inode: %lx, cache_inode %lx\n",
+ (ulong) redirected_inode, (ulong) cache_inode);
+
+ CDEBUG(D_SNAP, "cache_inode: %lx, ino %ld, sb %lx, count %d\n",
+ (ulong) cache_inode, cache_inode->i_ino,
+ (ulong) cache_inode->i_sb, cache_inode->i_count);
+
+ iput(cache_inode);
+ EXIT;
+ return redirected_inode;
+}
+
+
+/* super operations */
+static void clonefs_read_inode(struct inode *inode)
+{
+ struct inode *cache_inode;
+
+ ENTRY;
+
+ CDEBUG(D_SNAP, "inode: %lx, ino %ld, sb %lx, count %d\n",
+ (ulong) inode , inode->i_ino, (long) inode->i_sb,
+ inode->i_count);
+
+ /* redirecting inode in the cache */
+ cache_inode = clonefs_get_inode(inode);
+ if (!cache_inode) {
+ make_bad_inode(inode);
+ EXIT;
+ return;
+ }
+ /* copy attrs of that inode to our clone inode */
+ snapfs_cpy_attrs(inode, cache_inode);
+
+ if (S_ISREG(inode->i_mode))
+ inode->i_op = &clonefs_file_inode_operations;
+ else if (S_ISDIR(inode->i_mode))
+ inode->i_op = &clonefs_dir_inode_operations;
+ else if (S_ISLNK(inode->i_mode))
+ inode->i_op = &clonefs_symlink_inode_operations;
+ else if (S_ISCHR(inode->i_mode))
+ inode->i_op = &chrdev_inode_operations;
+ else if (S_ISBLK(inode->i_mode))
+ inode->i_op = &blkdev_inode_operations;
+ else if (S_ISFIFO(inode->i_mode))
+ init_fifo(inode);
+
+ iput(cache_inode);
+
+ CDEBUG(D_SNAP, "cache_inode: %lx ino %ld, sb %lx, count %d\n",
+ (ulong) cache_inode, cache_inode->i_ino,
+ (ulong) cache_inode->i_sb, cache_inode->i_count);
+ EXIT;
+ return;
+}
+
+
+static void clonefs_put_super(struct super_block *sb)
+{
+ struct snap_clone_info *clone_sb;
+
+ ENTRY;
+ CDEBUG(D_SUPER, "sb %lx, &sb->u.generic_sbp: %lx\n",
+ (ulong) sb, (ulong) &sb->u.generic_sbp);
+ clone_sb = (struct snap_clone_info *)&sb->u.generic_sbp;
+ dput( clone_sb->clone_cache->cache_sb->s_root );
+ list_del(&clone_sb->clone_list_entry);
+
+ MOD_DEC_USE_COUNT;
+
+ EXIT;
+}
+
+static int clonefs_statfs(struct super_block *sb, struct statfs *buf,
+ int bufsiz)
+{
+ struct snap_clone_info *clone_sb;
+ struct snap_cache *cache;
+
+ ENTRY;
+ clone_sb = (struct snap_clone_info *)&sb->u.generic_sbp;
+
+ cache = clone_sb->clone_cache;
+ if (!cache) {
+ printk("clone_statfs: no cache\n");
+ return -EINVAL;
+ }
+
+ EXIT;
+ return cache->cache_filter->o_caops.cache_sops->statfs
+ (cache->cache_sb, buf, bufsiz);
+}
+
+struct super_operations clone_super_ops =
+{
+ clonefs_read_inode, /* read_inode */
+ NULL, /* write_inode */
+ NULL, /* put_inode */
+ NULL, /* delete_inode */
+ NULL, /* notify_change */
+ clonefs_put_super, /* put_super */
+ NULL, /* write_super */
+ clonefs_statfs, /* statfs */
+ NULL /* remount_fs */
+};
+
+
+/* ***************** end of clonefs super ops ******************* */
+/* ***************** begin clonefs dir ops ******************* */
+
+static void d_unalloc(struct dentry *dentry)
+{
+
+ list_del(&dentry->d_hash);
+ INIT_LIST_HEAD(&dentry->d_hash);
+ dput(dentry); /* this will free the dentry memory */
+}
+
+/*
+ * Return the underlying fs dentry with name in 'dentry' that points
+ * to the right inode. 'dir' is the clone fs directory to search for
+ * the 'dentry'.
+ */
+struct dentry *clonefs_lookup(struct inode *dir, struct dentry *dentry)
+{
+ struct inode *cache_dir;
+ struct dentry *cache_dentry;
+ struct inode *cache_inode;
+ struct dentry *result;
+ struct inode *inode;
+ struct snap_clone_info *clone_sb;
+
+ ENTRY;
+
+ cache_dir = clonefs_get_inode(dir);
+
+ cache_dentry = d_alloc(dentry->d_parent, &dentry->d_name);
+ if (!cache_dentry) {
+ iput(cache_dir);
+ EXIT;
+ return ERR_PTR(-ENOENT);
+ }
+
+ /* Lock cache directory inode. */
+ down(&cache_dir->i_sem);
+ /*
+ * Call underlying fs lookup function to set the 'd_inode' pointer
+ * to the corresponding directory inode.
+ *
+ * Note: If the lookup function does not return NULL, return
+ * from 'clone_lookup' with an error.
+ */
+ result = cache_dir->i_op->lookup(cache_dir, cache_dentry);
+ if (result) {
+ dput(cache_dentry);
+ up(&cache_dir->i_sem);
+ iput(cache_dir);
+ dentry->d_inode = NULL;
+ EXIT;
+ return ERR_PTR(-ENOENT);
+ }
+ /* Unlock cache directory inode. */
+ up(&cache_dir->i_sem);
+
+ /*
+ * If there is no inode pointer in the underlying fs 'cache_dentry'
+ * then the directory doesn't have an entry with this name. In fs/ext2
+ * we see that we return 0 and put dentry->d_inode = NULL;
+ */
+ cache_inode = cache_dentry->d_inode;
+ if ( cache_inode == NULL ) {
+ inode = NULL;
+ } else {
+ clone_sb = (struct snap_clone_info *) &dir->i_sb->u.generic_sbp;
+ /* note, iget below will follow a redirector, since
+ it calls into clone_read_inode
+ */
+ inode = iget(dir->i_sb, cache_inode->i_ino);
+ }
+
+ /* dput(cache_dentry) will not put the dentry away
+ * immediately, unless we first arrange that its hash list is
+ * empty.
+ */
+
+ if ( cache_inode != NULL ) {
+ CDEBUG(D_INODE, "cache ino %ld, count %d, dir %ld, count %d\n",
+ cache_inode->i_ino, cache_inode->i_count, cache_dir->i_ino,
+ cache_dir->i_count);
+ }
+
+ d_unalloc(cache_dentry);
+ iput(cache_dir);
+
+ /*
+ * Add 'inode' to the directory entry 'dentry'.
+ */
+ d_add(dentry, inode);
+
+ EXIT;
+ return NULL;
+}
+
+
+/* instantiate a file handle to the cache file */
+static void clonefs_prepare_snapfile(struct inode *i,
+ struct file *clone_file,
+ struct inode *cache_inode,
+ struct file *cache_file,
+ struct dentry *cache_dentry)
+{
+ ENTRY;
+ cache_file->f_pos = clone_file->f_pos;
+ cache_file->f_mode = clone_file->f_mode;
+ cache_file->f_flags = clone_file->f_flags;
+ cache_file->f_count = clone_file->f_count;
+ cache_file->f_owner = clone_file->f_owner;
+ cache_file->f_op = cache_inode->i_op->default_file_ops;
+ cache_file->f_dentry = cache_dentry;
+ cache_file->f_dentry->d_inode = cache_inode;
+ EXIT;
+ return ;
+}
+
+/* update the clonefs file struct after IO in cache file */
+static void clonefs_restore_snapfile(struct inode *cache_inode,
+ struct file *cache_file,
+ struct inode *clone_inode,
+ struct file *clone_file)
+{
+ ENTRY;
+ cache_file->f_pos = clone_file->f_pos;
+ cache_inode->i_size = clone_inode->i_size;
+ EXIT;
+ return;
+}
+
+static int clonefs_readdir(struct file *file, void *dirent,
+ filldir_t filldir)
+{
+ int result;
+ struct inode *cache_inode;
+ struct file open_file;
+ struct dentry open_dentry;
+ struct inode *inode=file->f_dentry->d_inode;
+
+ ENTRY;
+
+ if(!inode) {
+ EXIT;
+ return -EINVAL;
+ }
+ cache_inode = clonefs_get_inode(inode);
+
+ if (!cache_inode) {
+ make_bad_inode(inode);
+ EXIT;
+ return -ENOMEM;
+ }
+
+ CDEBUG(D_INODE,"clone ino %ld\n",cache_inode->i_ino);
+
+ clonefs_prepare_snapfile(inode, file, cache_inode, &open_file,
+ &open_dentry);
+ /* potemkin case: we are handed a directory inode */
+ result = -ENOENT;
+ if (open_file.f_op->readdir) {
+ down(&cache_inode->i_sem);
+ result = open_file.f_op->readdir(&open_file, dirent, filldir);
+ up(&cache_inode->i_sem);
+ }
+ clonefs_restore_snapfile(inode, file, cache_inode, &open_file);
+ iput(cache_inode);
+ EXIT;
+ return result;
+}
+
+struct file_operations clonefs_dir_file_operations = {
+ NULL, /* lseek */
+ NULL, /* read -- bad */
+ NULL, /* write */
+ clonefs_readdir, /* readdir */
+ NULL, /* select */
+ NULL, /* ioctl */
+ NULL, /* mmap */
+ NULL, /* open */
+ NULL,
+ NULL, /* release */
+ NULL, /* fsync */
+ NULL,
+ NULL,
+ NULL
+};
+
+struct inode_operations clonefs_dir_inode_operations =
+{
+ &clonefs_dir_file_operations,
+ NULL, /* create */
+ clonefs_lookup, /* lookup */
+ NULL, /* link */
+ NULL, /* unlink */
+ NULL, /* symlink */
+ NULL, /* mkdir */
+ NULL, /* rmdir */
+ NULL, /* mknod */
+ NULL, /* rename */
+ NULL, /* readlink */
+ NULL, /* follow_link */
+ NULL, /* readpage */
+ NULL, /* writepage */
+ NULL, /* bmap */
+ NULL, /* truncate */
+ NULL, /* permission */
+ NULL, /* smap */
+ NULL, /* update page */
+ NULL, /* revalidate */
+};
+
+
+/* ***************** end of clonefs dir ops ******************* */
+/* ***************** begin clonefs file ops ******************* */
+
+int clonefs_readpage(struct file *file, struct page *page)
+{
+ int result = 0;
+ struct inode *cache_inode;
+ struct file open_file;
+ struct dentry open_dentry;
+ struct inode *inode;
+
+ ENTRY;
+
+ inode = file->f_dentry->d_inode;
+ cache_inode = clonefs_get_inode(file->f_dentry->d_inode);
+ if (!cache_inode) {
+ make_bad_inode(file->f_dentry->d_inode);
+ EXIT;
+ return -ENOMEM;
+ }
+
+ clonefs_prepare_snapfile(inode, file, cache_inode, &open_file,
+ &open_dentry);
+ /* tell currentfs_readpage the primary inode number */
+ open_dentry.d_fsdata = (void*)inode->i_ino;
+
+ /* potemkin case: we are handed a directory inode */
+ down(&cache_inode->i_sem);
+ /* XXX - readpage NULL on directories... */
+ if (cache_inode->i_op->readpage == NULL)
+ printk("Yes, Grigori, directories are a problem.\n");
+ else
+ cache_inode->i_op->readpage(&open_file, page);
+ up(&cache_inode->i_sem);
+ clonefs_restore_snapfile(inode, file, cache_inode, &open_file);
+ iput(cache_inode);
+ EXIT;
+ return result;
+}
+
+
+struct file_operations clonefs_file_file_operations = {
+ NULL, /* lseek */
+ generic_file_read, /* read -- bad */
+ NULL, /* write */
+ NULL, /* readdir */
+ NULL, /* select */
+ NULL, /* ioctl */
+ generic_file_mmap, /* mmap */
+ NULL, /* open */
+ NULL,
+ NULL, /* release */
+ NULL, /* fsync */
+ NULL,
+ NULL,
+ NULL
+};
+
+struct inode_operations clonefs_file_inode_operations =
+{
+ &clonefs_file_file_operations,
+ NULL, /* create */
+ NULL, /* lookup */
+ NULL, /* link */
+ NULL, /* unlink */
+ NULL, /* symlink */
+ NULL, /* mkdir */
+ NULL, /* rmdir */
+ NULL, /* mknod */
+ NULL, /* rename */
+ NULL, /* readlink */
+ NULL, /* follow_link */
+ clonefs_readpage, /* readpage */
+ NULL, /* writepage */
+ NULL, /* bmap */
+ NULL, /* truncate */
+ NULL, /* permission */
+ NULL, /* smap */
+ NULL, /* update page */
+ NULL, /* revalidate */
+};
+
+
+
+/* ***************** end of clonefs file ops ******************* */
+/* ***************** begin clonefs symlink ops ******************* */
+
+int clonefs_readlink(struct dentry *dentry, char *buf, int len)
+{
+ int res;
+ struct inode * cache_inode;
+ struct inode * old_inode;
+
+ ENTRY;
+
+ cache_inode = clonefs_get_inode(dentry->d_inode);
+
+ res = -ENOENT;
+
+ if ( ! cache_inode ) {
+ CDEBUG(D_INODE, "clonefs_get_inode failed, NULL\n");
+ EXIT;
+ return res;
+ }
+
+ /* XXX: shall we allocate a new dentry ?
+ The following is safe for ext2, etc. because ext2_readlink only
+ use the inode info */
+
+ /* save the old dentry inode */
+ old_inode = dentry->d_inode;
+ /* set dentry inode to cache inode */
+ dentry->d_inode = cache_inode;
+
+ if ( cache_inode->i_op->readlink ) {
+ res = cache_inode->i_op->readlink(dentry, buf, len);
+ }else {
+ CDEBUG(D_INODE,"NO readlink for ino %lu\n", cache_inode->i_ino);
+ }
+
+ /* restore the old inode */
+ dentry->d_inode = old_inode;
+
+ iput(cache_inode);
+
+ EXIT;
+ return res;
+}
+
+struct dentry * clonefs_follow_link(struct dentry * dentry,
+ struct dentry *base,
+ unsigned int follow)
+{
+ struct dentry * res;
+ struct inode * cache_inode;
+ struct inode * old_inode;
+
+ ENTRY;
+ res = ERR_PTR(-ENOENT);
+
+ cache_inode = clonefs_get_inode(dentry->d_inode);
+ if ( ! cache_inode ) {
+ CDEBUG(D_INODE, "clonefs_get_inode failed, NULL\n");
+ EXIT;
+ return res;
+ }
+
+ /* XXX: shall we allocate a new dentry ?
+ The following is safe for ext2, etc. because ext2_follow_link
+ only use the inode info */
+
+ /* save the old dentry inode */
+ old_inode = dentry->d_inode;
+ /* set dentry inode to cache inode */
+ dentry->d_inode = cache_inode;
+
+ if ( cache_inode->i_op->follow_link ) {
+ res = cache_inode->i_op->follow_link(dentry, base, follow);
+ }
+
+ /* restore the old inode */
+ dentry->d_inode = old_inode;
+
+ iput(cache_inode);
+
+ EXIT;
+ return res;
+}
+
+struct inode_operations clonefs_symlink_inode_operations =
+{
+ NULL, /* no file operations */
+ NULL, /* create */
+ NULL, /* lookup */
+ NULL, /* link */
+ NULL, /* unlink */
+ NULL, /* symlink */
+ NULL, /* mkdir */
+ NULL, /* rmdir */
+ NULL, /* mknod */
+ NULL, /* rename */
+ clonefs_readlink, /* readlink */
+ clonefs_follow_link,/* follow_link */
+ NULL, /* readpage */
+ NULL, /* writepage */
+ NULL, /* bmap */
+ NULL, /* truncate */
+ NULL, /* permission */
+ NULL, /* smap */
+ NULL, /* update page */
+ NULL, /* revalidate */
+};
+
+
diff --git a/lustre/snapfs/dcache.c b/lustre/snapfs/dcache.c
new file mode 100644
index 0000000000..88ce4bb54c
--- /dev/null
+++ b/lustre/snapfs/dcache.c
@@ -0,0 +1,56 @@
+/*
+ * Directory operations for SnapFS filesystem
+ */
+
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/fs.h>
+#include <linux/stat.h>
+#include <linux/errno.h>
+#include <linux/locks.h>
+#include <asm/segment.h>
+#include <asm/uaccess.h>
+#include <linux/string.h>
+
+#include <linux/filter.h>
+#include <linux/snapfs.h>
+#include <linux/snapsupport.h>
+
+/* called when a cache lookup succeeds */
+
+/* XXX PJB: the intent here is to make sure that inodes which are
+ currently primary inodes under .snap directories are dropped when
+ they are COWED. It seems hard to me to get semantics that are equally
+ good as for mounted snap_clone file systems, but we should try to get
+ close
+*/
+static int currentfs_dentry_revalidate(struct dentry *de, int flag)
+{
+// struct inode *inode = de->d_inode;
+ ENTRY;
+
+ /* unless an ancestor is a .snap directory there is nothing to do */
+#if 0
+ if ( !currentfs_is_under_dotsnap(dentry) ) {
+ EXIT;
+ return 1;
+ }
+ /* XXX PJB get this to work guys! */
+ if ( de->d_parent == "dotsnap inode" &&
+ inode_is_newer_than(find_time_by_name(de->d_parent->d_name.name))){
+ 1. drop this dentry
+ 2. make sure the VFS does a new lookup
+ 3. probably all you need to do is
+ return 0;
+ }
+#else
+ return 1;
+#endif
+}
+
+struct dentry_operations currentfs_dentry_ops =
+{
+ d_revalidate: currentfs_dentry_revalidate
+};
+
diff --git a/lustre/snapfs/dir.c b/lustre/snapfs/dir.c
new file mode 100644
index 0000000000..0b83fa147c
--- /dev/null
+++ b/lustre/snapfs/dir.c
@@ -0,0 +1,777 @@
+/*
+ * dir.c
+ */
+
+#define EXPORT_SYMTAB
+
+
+#define __NO_VERSION__
+#include <linux/module.h>
+#include <asm/uaccess.h>
+#include <linux/sched.h>
+#include <linux/stat.h>
+#include <linux/string.h>
+#include <linux/locks.h>
+#include <linux/quotaops.h>
+#include <linux/list.h>
+#include <linux/file.h>
+#include <asm/bitops.h>
+#include <asm/byteorder.h>
+
+#include <linux/filter.h>
+#include <linux/snapfs.h>
+#include <linux/snapsupport.h>
+
+#ifdef CONFIG_SNAPFS_EXT3
+void ext3_orphan_del(handle_t *handle, struct inode *inode);
+#endif
+
+static ino_t get_parent_ino(struct inode * inode)
+{
+ ino_t ino = 0;
+ struct dentry * dentry;
+
+ if (list_empty(&inode->i_dentry)) {
+ printk("snapfs ERROR: no dentry for ino %lu\n", inode->i_ino);
+ return 0;
+ }
+
+ dentry = dget(list_entry(inode->i_dentry.next, struct dentry, d_alias));
+
+ if(dentry->d_parent->d_inode)
+ ino = dentry->d_parent->d_inode->i_ino;
+
+ dput(dentry);
+ return ino;
+
+}
+
+static void d_unadd_iput(struct dentry *dentry)
+{
+ list_del(&dentry->d_alias);
+ INIT_LIST_HEAD(&dentry->d_alias);
+ list_del(&dentry->d_hash);
+ INIT_LIST_HEAD(&dentry->d_hash);
+ iput(dentry->d_inode);
+ dentry->d_inode = NULL;
+}
+
+/* XXX check the return values */
+static struct dentry *currentfs_lookup(struct inode * dir,struct dentry *dentry)
+{
+ struct snap_cache *cache;
+ struct dentry *rc;
+ struct inode_operations *iops;
+ struct inode *cache_inode;
+ int index;
+
+ ENTRY;
+
+ cache = snap_find_cache(dir->i_dev);
+ if ( !cache ) {
+ EXIT;
+ return ERR_PTR(-EINVAL);
+ }
+
+ if ( dentry->d_name.len == strlen(".snap") &&
+ (memcmp(dentry->d_name.name, ".snap", strlen(".snap")) == 0) ) {
+ struct inode *snap;
+ ino_t ino;
+
+ /* Don't permit .snap in clonefs */
+ if( dentry->d_sb != cache->cache_sb )
+ return ERR_PTR(-ENOENT);
+
+ /* Don't permit .snap under .snap */
+ if( currentfs_is_under_dotsnap(dentry) )
+ return ERR_PTR(-ENOENT);
+
+ ino = 0xF0000000 | dir->i_ino;
+ snap = iget(dir->i_sb, ino);
+ CDEBUG(D_INODE, ".snap inode ino %ld, mode %o\n", snap->i_ino, snap->i_mode);
+ d_add(dentry, snap);
+ EXIT;
+ return NULL;
+ }
+
+ iops = filter_c2cdiops(cache->cache_filter);
+ if (!iops || !iops->lookup) {
+ EXIT;
+ return ERR_PTR(-EINVAL);
+ }
+
+ rc = iops->lookup(dir, dentry);
+ if ( rc || !dentry->d_inode) {
+ EXIT;
+ return NULL;
+ }
+
+ /*
+ * If we are under dotsnap, we need save extra data into
+ * dentry->d_fsdata: For dir, we only need _this_ snapshot's index;
+ * For others, save primary ino, with it we could found index later
+ * anyway
+ */
+ cache_inode = dentry->d_inode;
+ if ( (index = currentfs_is_under_dotsnap(dentry)) ) {
+ struct snapshot_operations *snapops;
+ struct inode *ind_inode;
+ ino_t pri_ino, ind_ino;
+
+ pri_ino = cache_inode->i_ino;
+ snapops = filter_c2csnapops(cache->cache_filter);
+ if( !snapops )
+ goto err_out;
+
+ ind_ino = snapops->get_indirect_ino(cache_inode, index);
+ if( ind_ino <=0 && ind_ino != -ENOATTR )
+ goto err_out;
+ else if( ind_ino != -ENOATTR ){
+ ind_inode = iget(cache_inode->i_sb, ind_ino);
+ if( !ind_inode ){
+ goto err_out;
+ }
+ list_del(&dentry->d_alias);
+ INIT_LIST_HEAD(&dentry->d_alias);
+ list_add(&dentry->d_alias, &ind_inode->i_dentry);
+ dentry->d_inode = ind_inode;
+ iput(cache_inode);
+ }
+
+ if( S_ISDIR(dentry->d_inode->i_mode) )
+ dentry->d_fsdata = (void*)index;
+ else
+ dentry->d_fsdata = (void*)pri_ino;
+ }
+
+ EXIT;
+ return NULL;
+
+#if 0
+ /* XXX: PJB these need to be set up again. See dcache.c */
+ printk("set up dentry ops\n");
+ CDEBUG(D_CACHE, "\n");
+ filter_setup_dentry_ops(cache->cache_filter,
+ dentry->d_op, ¤tfs_dentry_ops);
+ dentry->d_op = filter_c2udops(cache->cache_filter);
+ CDEBUG(D_CACHE, "\n");
+#endif
+
+err_out:
+ d_unadd_iput(dentry);
+ EXIT;
+ return ERR_PTR(-EINVAL);
+}
+
+static int currentfs_create(struct inode *dir, struct dentry *dentry, int mode)
+{
+ struct snap_cache *cache;
+ int rc;
+ struct inode_operations *iops;
+ void *handle = NULL;
+
+ ENTRY;
+
+ if (currentfs_is_under_dotsnap(dentry)) {
+ EXIT;
+ return -EPERM;
+ }
+
+ cache = snap_find_cache(dir->i_dev);
+ if ( !cache ) {
+ EXIT;
+ return -EINVAL;
+ }
+
+ handle = snap_trans_start(cache, dir, SNAP_OP_CREATE);
+
+ if ( snap_needs_cow(dir) != -1 ) {
+ printk("snap_needs_cow for ino %lu \n",dir->i_ino);
+ snap_debug_device_fail(dir->i_dev, SNAP_OP_CREATE, 1);
+ snap_do_cow(dir, get_parent_ino(dir), 0);
+ }
+
+ iops = filter_c2cdiops(cache->cache_filter);
+ if (!iops ||
+ !iops->create) {
+ rc = -EINVAL;
+ goto exit;
+ }
+ snap_debug_device_fail(dir->i_dev, SNAP_OP_CREATE, 2);
+ rc = iops->create(dir, dentry, mode);
+
+ /* XXX now set the correct snap_{file,dir,sym}_iops */
+ if ( ! dentry->d_inode) {
+ printk("Error in currentfs_create, dentry->d_inode is NULL\n");
+ goto exit;
+ }
+
+ if ( S_ISDIR(dentry->d_inode->i_mode) )
+ dentry->d_inode->i_op = filter_c2udiops(cache->cache_filter);
+ else if ( S_ISREG(dentry->d_inode->i_mode) ) {
+ if ( !filter_c2cfiops(cache->cache_filter) ) {
+ filter_setup_file_ops(cache->cache_filter,
+ dentry->d_inode->i_op, ¤tfs_file_iops);
+ }
+ dentry->d_inode->i_op = filter_c2ufiops(cache->cache_filter);
+ }
+ printk("inode %lu, i_op %p\n", dentry->d_inode->i_ino, dentry->d_inode->i_op);
+
+ snap_debug_device_fail(dir->i_dev, SNAP_OP_CREATE, 3);
+
+exit:
+ snap_trans_commit(cache, handle);
+ EXIT;
+ return rc;
+}
+
+static int currentfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
+{
+ struct snap_cache *cache;
+ int rc;
+ struct inode_operations *iops;
+ void *handle = NULL;
+
+ ENTRY;
+
+ if (currentfs_is_under_dotsnap(dentry)) {
+ EXIT;
+ return -EPERM;
+ }
+
+ cache = snap_find_cache(dir->i_dev);
+ if ( !cache ) {
+ EXIT;
+ return -EINVAL;
+ }
+
+ handle = snap_trans_start(cache, dir, SNAP_OP_MKDIR);
+
+ if ( snap_needs_cow(dir) != -1 ) {
+ CDEBUG(D_FILE, "snap_needs_cow for ino %lu \n",dir->i_ino);
+ snap_debug_device_fail(dir->i_dev, SNAP_OP_MKDIR, 1);
+ snap_do_cow(dir, get_parent_ino(dir), 0);
+ }
+
+ iops = filter_c2cdiops(cache->cache_filter);
+ if (!iops ||
+ !iops->mkdir) {
+ rc = -EINVAL;
+ goto exit;
+ }
+
+ snap_debug_device_fail(dir->i_dev, SNAP_OP_MKDIR, 2);
+ rc = iops->mkdir(dir, dentry, mode);
+
+ if ( rc )
+ goto exit;
+
+ /* XXX now set the correct snap_{file,dir,sym}_iops */
+ if ( dentry->d_inode) {
+ dentry->d_inode->i_op = filter_c2udiops(cache->cache_filter);
+ printk("inode %lu, i_op %p\n", dentry->d_inode->i_ino, dentry->d_inode->i_op);
+ } else {
+ printk("Error in currentfs_mkdir, dentry->d_inode is NULL\n");
+ }
+
+ snap_debug_device_fail(dir->i_dev, SNAP_OP_MKDIR, 3);
+
+exit:
+ snap_trans_commit(cache, handle);
+ EXIT;
+ return rc;
+}
+
+static int currentfs_link (struct dentry * old_dentry, struct inode * dir,
+ struct dentry *dentry)
+{
+ struct snap_cache *cache;
+ int rc;
+ struct inode_operations *iops;
+ void *handle = NULL;
+
+ ENTRY;
+
+ if (currentfs_is_under_dotsnap(dentry)) {
+ EXIT;
+ return -EPERM;
+ }
+
+ cache = snap_find_cache(dir->i_dev);
+ if ( !cache ) {
+ EXIT;
+ return -EINVAL;
+ }
+
+ handle = snap_trans_start(cache, dir, SNAP_OP_LINK);
+
+ if ( snap_needs_cow(dir) != -1 ) {
+ printk("snap_needs_cow for ino %lu \n",dir->i_ino);
+ snap_debug_device_fail(dir->i_dev, SNAP_OP_LINK, 1);
+ snap_do_cow(dir, get_parent_ino(dir), 0);
+ }
+ if ( snap_needs_cow(old_dentry->d_inode) != -1 ) {
+ printk("snap_needs_cow for ino %lu \n",old_dentry->d_inode->i_ino);
+ snap_debug_device_fail(dir->i_dev, SNAP_OP_LINK, 2);
+ snap_do_cow(old_dentry->d_inode, dir->i_ino, 0);
+ }
+
+ iops = filter_c2cdiops(cache->cache_filter);
+ if (!iops ||
+ !iops->link) {
+ rc = -EINVAL;
+ goto exit;
+ }
+ snap_debug_device_fail(dir->i_dev, SNAP_OP_LINK, 2);
+ rc = iops->link(old_dentry,dir, dentry);
+ snap_debug_device_fail(dir->i_dev, SNAP_OP_LINK, 3);
+
+exit:
+ snap_trans_commit(cache, handle);
+ EXIT;
+ return rc;
+}
+
+static int currentfs_symlink(struct inode *dir, struct dentry *dentry,
+ const char * symname)
+{
+ struct snap_cache *cache;
+ int rc;
+ struct inode_operations *iops;
+ void *handle = NULL;
+
+ ENTRY;
+
+ cache = snap_find_cache(dir->i_dev);
+ if ( !cache ) {
+ EXIT;
+ return -EINVAL;
+ }
+
+ handle = snap_trans_start(cache, dir, SNAP_OP_SYMLINK);
+
+ if ( snap_needs_cow(dir) != -1 ) {
+ printk("snap_needs_cow for ino %lu \n",dir->i_ino);
+ snap_debug_device_fail(dir->i_dev, SNAP_OP_SYMLINK, 1);
+ snap_do_cow(dir, get_parent_ino(dir), 0);
+ }
+
+ iops = filter_c2cdiops(cache->cache_filter);
+ if (!iops ||
+ !iops->symlink) {
+ rc = -EINVAL;
+ goto exit;
+ }
+ snap_debug_device_fail(dir->i_dev, SNAP_OP_SYMLINK, 2);
+ rc = iops->symlink(dir, dentry, symname);
+ snap_debug_device_fail(dir->i_dev, SNAP_OP_SYMLINK, 3);
+
+exit:
+ snap_trans_commit(cache, handle);
+ EXIT;
+ return rc;
+}
+
+static int currentfs_mknod(struct inode *dir, struct dentry *dentry, int mode,
+ int rdev)
+{
+ struct snap_cache *cache;
+ int rc;
+ struct inode_operations *iops;
+ void *handle = NULL;
+
+ ENTRY;
+
+ if (currentfs_is_under_dotsnap(dentry)) {
+ EXIT;
+ return -EPERM;
+ }
+
+ cache = snap_find_cache(dir->i_dev);
+ if ( !cache ) {
+ EXIT;
+ return -EINVAL;
+ }
+
+ handle = snap_trans_start(cache, dir, SNAP_OP_MKNOD);
+
+ if ( snap_needs_cow(dir) != -1 ) {
+ printk("snap_needs_cow for ino %lu \n",dir->i_ino);
+ snap_debug_device_fail(dir->i_dev, SNAP_OP_MKNOD, 1);
+ snap_do_cow(dir, get_parent_ino(dir), 0);
+ }
+
+ iops = filter_c2cdiops(cache->cache_filter);
+ if (!iops ||
+ !iops->mknod) {
+ rc = -EINVAL;
+ goto exit;
+ }
+ snap_debug_device_fail(dir->i_dev, SNAP_OP_MKNOD, 2);
+ rc = iops->mknod(dir, dentry, mode, rdev);
+ snap_debug_device_fail(dir->i_dev, SNAP_OP_MKNOD, 3);
+
+ /* XXX do we need to set the correct snap_{*}_iops */
+
+exit:
+ snap_trans_commit(cache, handle);
+ EXIT;
+ return rc;
+}
+
+static int currentfs_rmdir(struct inode *dir, struct dentry *dentry)
+{
+ struct snap_cache *cache;
+ int rc;
+ struct inode_operations *iops;
+ struct inode *inode = NULL;
+// time_t i_ctime = 0;
+ nlink_t i_nlink = 0;
+ off_t i_size = 0;
+ ino_t ino = 0;
+ int keep_inode = 0;
+// struct dentry_operations *save_dop = NULL;
+ void *handle = NULL;
+
+ ENTRY;
+
+ if (currentfs_is_under_dotsnap(dentry)) {
+ EXIT;
+ return -EPERM;
+ }
+
+ cache = snap_find_cache(dir->i_dev);
+ if ( !cache ) {
+ EXIT;
+ return -EINVAL;
+ }
+
+ handle = snap_trans_start(cache, dir, SNAP_OP_RMDIR);
+
+ if ( snap_needs_cow(dir) != -1 ) {
+ printk("snap_needs_cow for ino %lu \n",dir->i_ino);
+ snap_debug_device_fail(dir->i_dev, SNAP_OP_RMDIR, 1);
+ snap_do_cow(dir, get_parent_ino(dir), 0);
+ }
+
+ iops = filter_c2cdiops(cache->cache_filter);
+ if (!iops ||
+ !iops->rmdir) {
+ rc = -EINVAL;
+ goto exit;
+ }
+
+ /* XXX : there are two cases that we can't remove this inode from disk.
+ 1. the inode needs to be cowed.
+ 2. the inode is a redirector.
+ then we must keep this inode(dir) so that the inode
+ will not be deleted after rmdir, will only remove dentry
+ */
+
+ if( snap_needs_cow(dentry->d_inode) != -1) {
+ snap_debug_device_fail(dir->i_dev, SNAP_OP_RMDIR, 2);
+ snap_do_cow (dentry->d_inode, dir->i_ino,
+ SNAP_DEL_PRI_WITHOUT_IND);
+ keep_inode = 1;
+ }
+ else if( snap_is_redirector(dentry->d_inode) ) {
+ snap_debug_device_fail(dir->i_dev, SNAP_OP_RMDIR, 3);
+ snap_do_cow(dentry->d_inode, dir->i_ino, SNAP_DEL_PRI_WITH_IND);
+ keep_inode = 1;
+ }
+#if 0
+ if ( keep_inode ) {
+ printk("set up dentry ops, before %p\n",dentry->d_op);
+ save_dop = dentry->d_op;
+
+ filter_setup_dentry_ops(cache->cache_filter,
+ dentry->d_op, ¤tfs_dentry_ops);
+ dentry->d_op = filter_c2udops(cache->cache_filter);
+
+ printk("set up dentry ops, after %p\n",dentry->d_op);
+
+ }
+
+#endif
+
+ if( keep_inode && dentry->d_inode ) {
+ ino = dentry->d_inode->i_ino;
+ // i_ctime = dentry->d_inode->i_ctime;
+ i_nlink = dentry->d_inode->i_nlink;
+ i_size = dentry->d_inode->i_size;
+
+}
+
+ snap_debug_device_fail(dir->i_dev, SNAP_OP_RMDIR, 4);
+ rc = iops->rmdir(dir, dentry);
+ snap_debug_device_fail(dir->i_dev, SNAP_OP_RMDIR, 5);
+
+ /* XXX : check this */
+#if 0
+ if ( keep_inode ) {
+ dentry->d_op = save_dop;
+ printk("restore dentry ops, now at %p\n",dentry->d_op);
+ }
+
+#endif
+
+ if( keep_inode && ino) {
+ inode = iget ( dir->i_sb, ino);
+ if( inode) {
+// inode->i_ctime = i_ctime;
+ inode->i_nlink = i_nlink;
+ inode->i_size = i_size;
+ mark_inode_dirty(inode);
+ iput( inode);
+#ifdef CONFIG_SNAPFS_EXT3
+ /*
+ * In Ext3, rmdir() will put this inode into
+ * orphan list, we must remove it out. It's ugly!!
+ */
+ if( cache->cache_type == FILTER_FS_EXT3 )
+ ext3_orphan_del(handle, inode);
+#endif
+ snap_debug_device_fail(dir->i_dev, SNAP_OP_RMDIR, 6);
+ }
+ }
+
+exit:
+ snap_trans_commit(cache, handle);
+ EXIT;
+ return rc;
+}
+
+static int currentfs_unlink(struct inode *dir, struct dentry *dentry)
+{
+ struct inode *inode = dentry->d_inode;
+ struct snap_cache *cache;
+ int rc;
+ struct inode_operations *iops;
+ void *handle = NULL;
+
+ ENTRY;
+
+ if (currentfs_is_under_dotsnap(dentry)) {
+ EXIT;
+ return -EPERM;
+ }
+
+ cache = snap_find_cache(dir->i_dev);
+ if ( !cache ) {
+ EXIT;
+ return -EINVAL;
+ }
+
+ handle = snap_trans_start(cache, dir, SNAP_OP_UNLINK);
+
+ if ( snap_needs_cow(dir) != -1 ) {
+ printk("snap_needs_cow for ino %lu \n",dir->i_ino);
+ snap_debug_device_fail(dir->i_dev, SNAP_OP_UNLINK, 1);
+ snap_do_cow(dir, get_parent_ino(dir), 0);
+ }
+
+ iops = filter_c2cdiops(cache->cache_filter);
+ if (!iops ||
+ !iops->unlink) {
+ rc = -EINVAL;
+ goto exit;
+ }
+
+ /* XXX : if nlink for this inode is 1, there are two cases that we
+ can't remove this inode from disk.
+ 1. the inode needs to be cowed.
+ 2. the inode is a redirector.
+ then we increament dentry->d_inode->i_nlink so that the inode
+ will not be deleted after unlink, will only remove dentry
+ */
+
+ if( snap_needs_cow (inode) != -1) {
+ /* call snap_do_cow with DEL_WITHOUT_IND option */
+ snap_debug_device_fail(dir->i_dev, SNAP_OP_UNLINK, 2);
+ snap_do_cow(inode, dir->i_ino,SNAP_DEL_PRI_WITHOUT_IND);
+ if( inode->i_nlink == 1 )
+ inode->i_nlink++;
+ }
+ else if( snap_is_redirector (inode) && inode->i_nlink == 1 ) {
+ /* call snap_do_cow with DEL_WITH_IND option
+ * just free the blocks of inode, not really delete it
+ */
+ snap_debug_device_fail(dir->i_dev, SNAP_OP_UNLINK, 3);
+ snap_do_cow (inode, dir->i_ino, SNAP_DEL_PRI_WITH_IND);
+ inode->i_nlink++;
+ }
+
+ snap_debug_device_fail(dir->i_dev, SNAP_OP_UNLINK, 4);
+ rc = iops->unlink(dir, dentry);
+ snap_debug_device_fail(dir->i_dev, SNAP_OP_UNLINK, 5);
+
+exit:
+ snap_trans_commit(cache, handle);
+ EXIT;
+ return rc;
+}
+
+static int currentfs_rename (struct inode * old_dir, struct dentry *old_dentry,
+ struct inode * new_dir, struct dentry *new_dentry)
+{
+ struct snap_cache *cache;
+ int rc;
+ struct inode_operations *iops;
+ void *handle = NULL;
+
+ ENTRY;
+
+ if (currentfs_is_under_dotsnap(old_dentry) ||
+ currentfs_is_under_dotsnap(new_dentry)) {
+ EXIT;
+ return -EPERM;
+ }
+
+ cache = snap_find_cache(old_dir->i_dev);
+ if ( !cache ) {
+ EXIT;
+ return -EINVAL;
+ }
+
+ handle = snap_trans_start(cache, old_dir, SNAP_OP_RENAME);
+
+ /* Always cow the old dir and old dentry->d_inode */
+ if ( snap_needs_cow(old_dir) != -1 ) {
+ printk("rename: needs_cow for old_dir %lu\n",old_dir->i_ino);
+ snap_debug_device_fail(old_dir->i_dev, SNAP_OP_RENAME, 1);
+ snap_do_cow(old_dir, get_parent_ino(old_dir), 0);
+ }
+ if( snap_needs_cow (old_dentry->d_inode) != -1) {
+ printk("rename: needs_cow for old_dentry, ino %lu\n",
+ old_dentry->d_inode->i_ino);
+ snap_debug_device_fail(old_dir->i_dev, SNAP_OP_RENAME, 2);
+ snap_do_cow(old_dentry->d_inode, old_dir->i_ino,0);
+ }
+
+ /* If it's not in the same dir, whether the new_dentry is NULL or not,
+ * we should cow the new_dir. Because rename will use the ino of
+ * old_dentry as the ino of the new_dentry in new_dir.
+ */
+ if(( old_dir != new_dir) ) {
+ if( snap_needs_cow(new_dir) !=-1 ){
+ printk("rename:snap_needs_cow for new_dir %lu\n",
+ new_dir->i_ino);
+ snap_debug_device_fail(old_dir->i_dev,SNAP_OP_RENAME,3);
+ snap_do_cow(new_dir, get_parent_ino(new_dir),0);
+ }
+ }
+
+#if 0
+ if( ( old_dir != new_dir) && ( new_dentry->d_inode )) {
+ if(snap_needs_cow(new_dentry->d_inode) !=-1 ){
+ printk("rename:needs_cow for new_entry ,ino %lu\n",
+ new_dentry->d_inode->i_ino);
+ snap_debug_device_fail(old_dir->i_dev, SNAP_OP_RENAME, 4);
+ snap_do_cow (new_dentry->d_inode,
+ new_dentry->d_parent->d_inode->i_ino, 0);
+ }
+ }
+#endif
+ /* The inode for the new_dentry will be freed for normal rename option.
+ * But we should keep this inode since we need to keep it available
+ * for the clone and for snap rollback
+ */
+ if( new_dentry->d_inode && new_dentry->d_inode->i_nlink == 1 ) {
+ if( snap_needs_cow (new_dentry->d_inode) != -1) {
+ /* call snap_do_cow with DEL_WITHOUT_IND option */
+ snap_debug_device_fail(old_dir->i_dev,SNAP_OP_RENAME,4);
+ snap_do_cow(new_dentry->d_inode, new_dir->i_ino,
+ SNAP_DEL_PRI_WITHOUT_IND);
+ new_dentry->d_inode->i_nlink++;
+ }
+ else if( snap_is_redirector (new_dentry->d_inode) ) {
+ /* call snap_do_cow with DEL_WITH_IND option
+ * just free the blocks of inode, not really delete it
+ */
+ snap_debug_device_fail(old_dir->i_dev,SNAP_OP_RENAME,4);
+ snap_do_cow (new_dentry->d_inode, new_dir->i_ino,
+ SNAP_DEL_PRI_WITH_IND);
+ new_dentry->d_inode->i_nlink++;
+ }
+ }
+
+ iops = filter_c2cdiops(cache->cache_filter);
+ if (!iops ||
+ !iops->rename) {
+ rc = -EINVAL;
+ goto exit;
+ }
+
+ snap_debug_device_fail(old_dir->i_dev, SNAP_OP_RENAME, 5);
+ rc = iops->rename(old_dir, old_dentry, new_dir, new_dentry);
+ snap_debug_device_fail(old_dir->i_dev, SNAP_OP_RENAME, 6);
+
+exit:
+ snap_trans_commit(cache, handle);
+ EXIT;
+ return rc;
+}
+
+static int currentfs_readdir(struct file *filp, void *dirent,
+ filldir_t filldir)
+{
+ struct snap_cache *cache;
+ struct file_operations *fops;
+ int rc;
+
+ ENTRY;
+ if( !filp || !filp->f_dentry || !filp->f_dentry->d_inode ) {
+ EXIT;
+ return -EINVAL;
+ }
+
+ cache = snap_find_cache(filp->f_dentry->d_inode->i_dev);
+ if ( !cache ) {
+ EXIT;
+ return -EINVAL;
+ }
+ fops = filter_c2cdfops( cache->cache_filter );
+ if( !fops ) {
+ EXIT;
+ return -EINVAL;
+ }
+
+ /*
+ * no action if we are under clonefs or .snap
+ */
+ if( cache->cache_show_dotsnap &&
+ (filp->f_dentry->d_sb == cache->cache_sb) &&
+ !currentfs_is_under_dotsnap(filp->f_dentry) ){
+ if( filp->f_pos == 0 ){
+ if( filldir(dirent, ".snap",
+ strlen(".snap")+1, filp->f_pos,
+ 0xF0000000|filp->f_dentry->d_inode->i_ino) ){
+ return -EINVAL;
+ }
+ filp->f_pos += strlen(".snap")+1;
+ }
+ filp->f_pos -= strlen(".snap")+1;
+ rc = fops->readdir(filp, dirent, filldir);
+ filp->f_pos += strlen(".snap")+1;
+ }else
+ rc = fops->readdir(filp, dirent, filldir);
+
+ return rc;
+}
+
+struct file_operations currentfs_dir_fops = {
+ readdir: currentfs_readdir
+};
+
+struct inode_operations currentfs_dir_iops = {
+ default_file_ops: ¤tfs_dir_fops,
+ create: currentfs_create,
+ mkdir: currentfs_mkdir,
+ link: currentfs_link,
+ symlink: currentfs_symlink,
+ mknod: currentfs_mknod,
+ rmdir: currentfs_rmdir,
+ unlink: currentfs_unlink,
+ rename: currentfs_rename,
+ lookup: currentfs_lookup
+};
diff --git a/lustre/snapfs/dotsnap.c b/lustre/snapfs/dotsnap.c
new file mode 100644
index 0000000000..19dfc1ca2d
--- /dev/null
+++ b/lustre/snapfs/dotsnap.c
@@ -0,0 +1,208 @@
+/*
+ * dotsnap.c - support for .snap directories
+ */
+
+#define EXPORT_SYMTAB
+
+
+#define __NO_VERSION__
+#include <linux/module.h>
+#include <asm/uaccess.h>
+#include <linux/sched.h>
+#include <linux/stat.h>
+#include <linux/string.h>
+#include <linux/locks.h>
+#include <linux/quotaops.h>
+#include <linux/list.h>
+#include <linux/file.h>
+#include <asm/bitops.h>
+#include <asm/byteorder.h>
+
+#include <linux/filter.h>
+#include <linux/snapfs.h>
+#include <linux/snapsupport.h>
+
+struct inode_operations dotsnap_inode_operations;
+struct file_operations dotsnap_file_operations;
+
+int currentfs_is_under_dotsnap(struct dentry *de)
+{
+ int index = 0;
+
+ while(de && de->d_parent != de) {
+ if ( de->d_inode && de->d_inode->i_ino & 0xF0000000 ) {
+ EXIT;
+ return index;
+ }
+ index = (int)de->d_fsdata;
+ de = de->d_parent;
+ }
+
+ EXIT;
+ return 0;
+}
+
+void currentfs_dotsnap_read_inode(struct snap_cache *cache,
+ struct inode *inode)
+{
+ int tableno = cache->cache_snap_tableno;
+ struct snap_table *table;
+ ENTRY;
+
+ table = &snap_tables[tableno];
+
+ inode->i_mode = S_IFDIR | 0755 ;
+ inode->i_op = &dotsnap_inode_operations;
+ inode->i_size = table->tbl_count - 1;
+ /* all except current form a subdirectory and . and .. */
+ inode->i_nlink = table->tbl_count -1 + 2;
+ inode->i_uid = 0;
+ inode->i_gid = 0;
+ EXIT;
+}
+
+struct dentry *dotsnap_lookup(struct inode *dir, struct dentry *dentry)
+{
+ struct snap_table *table;
+ struct snap_cache *cache;
+ int i;
+ int index;
+ int tableno;
+ ino_t ino;
+ struct inode *inode;
+ struct snapshot_operations *snapops;
+
+ ENTRY;
+
+ cache = snap_find_cache(dir->i_dev);
+ if ( !cache ) {
+ printk("dotsnap_readdir: cannot find cache\n");
+ make_bad_inode(dir);
+ EXIT;
+ return ERR_PTR(-EINVAL);
+ }
+
+ snapops = filter_c2csnapops(cache->cache_filter);
+ if (!snapops || !snapops->get_indirect_ino) {
+ EXIT;
+ return ERR_PTR(-EINVAL);
+ }
+
+ tableno = cache->cache_snap_tableno;
+ table = &snap_tables[tableno];
+
+ if( table->tbl_count <= 1 )
+ return NULL;
+
+ index = table->tbl_index[0];
+ for ( i = 1 ; i < table->tbl_count ; i++ ) {
+ if ( (dentry->d_name.len == strlen(table->tbl_name[i])) &&
+ (memcmp(dentry->d_name.name, table->tbl_name[i],
+ dentry->d_name.len) == 0) ) {
+ index = table->tbl_index[i];
+ break;
+ }
+ }
+
+ if( i >= table->tbl_count )
+ return ERR_PTR(-ENOENT);
+
+ inode = iget(dir->i_sb, dir->i_ino & (~0xF0000000));
+
+ if ( !inode )
+ return ERR_PTR(-EINVAL);
+
+ ino = snapops->get_indirect_ino(inode, index);
+ iput(inode);
+
+ if ( ino == -ENOATTR || ino == 0 ) {
+ ino = dir->i_ino & (~0xF0000000);
+ }
+
+ if ( ino == -EINVAL ) {
+ return ERR_PTR(-EINVAL);
+ }
+CDEBUG(D_INODE, "index %d, ino is %lu\n",index, ino);
+
+ inode = iget(dir->i_sb, ino);
+ d_add(dentry, inode);
+ dentry->d_fsdata = (void*)index;
+ inode->i_op = dentry->d_parent->d_parent->d_inode->i_op;
+ return NULL;
+}
+
+
+static int dotsnap_readdir(struct file * filp,
+ void * dirent, filldir_t filldir)
+{
+ unsigned int i;
+ int tableno;
+ struct snap_cache *cache;
+ struct snap_table *table;
+ struct snapshot_operations *snapops;
+
+ ENTRY;
+
+ cache = snap_find_cache(filp->f_dentry->d_inode->i_dev);
+ if ( !cache ) {
+ printk("dotsnap_readdir: cannot find cache\n");
+ make_bad_inode(filp->f_dentry->d_inode);
+ EXIT;
+ return -EINVAL;
+ }
+
+ snapops = filter_c2csnapops(cache->cache_filter);
+ if (!snapops || !snapops->get_indirect_ino) {
+ EXIT;
+ return -EINVAL;
+ }
+
+ tableno = cache->cache_snap_tableno;
+ table = &snap_tables[tableno];
+ CDEBUG(D_INODE, "\n");
+ for (i = filp->f_pos ; i < table->tbl_count -1 ; i++) {
+ int index;
+ struct inode *inode;
+ ino_t ino;
+
+ CDEBUG(D_INODE, "%d\n",i);
+
+ inode = filp->f_dentry->d_inode;
+ index = table->tbl_index[i+1];
+ ino = snapops->get_indirect_ino
+ (filp->f_dentry->d_inode, index);
+
+ CDEBUG(D_INODE, "\n");
+
+ if ( ino == -ENOATTR || ino == 0 ) {
+ ino = filp->f_dentry->d_parent->d_inode->i_ino;
+ }
+
+ CDEBUG(D_INODE, "\n");
+ if ( ino == -EINVAL ) {
+ return -EINVAL;
+ }
+
+ CDEBUG(D_INODE, "Listing %s\n", table->tbl_name[i+1]);
+ if (filldir(dirent, table->tbl_name[i+1],
+ strlen(table->tbl_name[i+1]),
+ filp->f_pos, ino) < 0){
+ CDEBUG(D_INODE, "\n");
+ break;
+ }
+ filp->f_pos++;
+ }
+ EXIT;
+ return 0;
+}
+
+
+struct file_operations dotsnap_file_operations = {
+ readdir: dotsnap_readdir, /* readdir */
+};
+
+struct inode_operations dotsnap_inode_operations =
+{
+ default_file_ops: &dotsnap_file_operations,
+ lookup: dotsnap_lookup
+};
diff --git a/lustre/snapfs/file.c b/lustre/snapfs/file.c
new file mode 100644
index 0000000000..38c5652c50
--- /dev/null
+++ b/lustre/snapfs/file.c
@@ -0,0 +1,259 @@
+/*
+ * file.c
+ */
+
+#define EXPORT_SYMTAB
+
+
+#define __NO_VERSION__
+#include <linux/module.h>
+#include <asm/uaccess.h>
+#include <linux/sched.h>
+#include <linux/stat.h>
+#include <linux/string.h>
+#include <linux/locks.h>
+#include <linux/quotaops.h>
+#include <linux/list.h>
+#include <linux/file.h>
+#include <asm/bitops.h>
+#include <asm/byteorder.h>
+
+#include <linux/filter.h>
+#include <linux/snapfs.h>
+#include <linux/snapsupport.h>
+
+/* instantiate a file handle to the cache file */
+static void currentfs_prepare_snapfile(struct inode *inode,
+ struct file *clone_file,
+ struct inode *cache_inode,
+ struct file *cache_file,
+ struct dentry *cache_dentry)
+{
+ ENTRY;
+ cache_file->f_pos = clone_file->f_pos;
+ cache_file->f_mode = clone_file->f_mode;
+ cache_file->f_flags = clone_file->f_flags;
+ cache_file->f_count = clone_file->f_count;
+ cache_file->f_owner = clone_file->f_owner;
+ cache_file->f_op = cache_inode->i_op->default_file_ops;
+ cache_file->f_dentry = cache_dentry;
+ cache_file->f_dentry->d_inode = cache_inode;
+ EXIT;
+ return ;
+}
+
+/* update the currentfs file struct after IO in cache file */
+static void currentfs_restore_snapfile(struct inode *cache_inode,
+ struct file *cache_file,
+ struct inode *clone_inode,
+ struct file *clone_file)
+{
+ ENTRY;
+ cache_file->f_pos = clone_file->f_pos;
+ EXIT;
+ return;
+}
+
+
+static ssize_t currentfs_write (struct file *filp, const char *buf,
+ size_t count, loff_t *ppos)
+{
+ struct snap_cache *cache;
+ struct inode *inode = filp->f_dentry->d_inode;
+ ssize_t rc;
+ struct file_operations *fops;
+ loff_t pos;
+ long block[2]={-1,-1}, mask, i;
+ struct snap_table *table;
+ int slot = 0;
+ int index = 0;
+ struct inode_operations *ciops;
+ struct inode *cache_inode = NULL;
+ struct snapshot_operations *snapops;
+
+ ENTRY;
+
+ if (currentfs_is_under_dotsnap(filp->f_dentry)) {
+ EXIT;
+ return -ENOSPC;
+ }
+
+ cache = snap_find_cache(inode->i_dev);
+ if ( !cache ) {
+ EXIT;
+ return -EINVAL;
+ }
+
+ if ( snap_needs_cow(inode) != -1 ) {
+ CDEBUG(D_FILE, "snap_needs_cow for ino %lu \n",inode->i_ino);
+ snap_do_cow(inode, filp->f_dentry->d_parent->d_inode->i_ino, 0);
+ }
+
+ fops = filter_c2cffops(cache->cache_filter);
+ if (!fops ||
+ !fops->write) {
+ EXIT;
+ return -EINVAL;
+ }
+
+ if (filp->f_flags & O_APPEND)
+ pos = inode->i_size;
+ else {
+ pos = *ppos;
+ if (pos != *ppos)
+ return -EINVAL;
+ }
+
+ /*
+ * we only need to copy back the first and last blocks
+ */
+ mask = inode->i_sb->s_blocksize-1;
+ if( pos & mask )
+ block[0] = pos >> inode->i_sb->s_blocksize_bits;
+ pos += count - 1;
+ if( (pos+1) & mask )
+ block[1] = pos >> inode->i_sb->s_blocksize_bits;
+ if( block[0] == block[1] )
+ block[1] = -1;
+
+ ciops = filter_c2cfiops(cache->cache_filter);
+ snapops = filter_c2csnapops(cache->cache_filter);
+
+ for( i=0; i<2; i++ ){
+ if( block[i]!=-1 && !ciops->bmap(inode, block[i]) ) {
+ table = &snap_tables[cache->cache_snap_tableno];
+ for (slot = table->tbl_count ; slot >= 1; slot--)
+ {
+ cache_inode = NULL;
+ index = table->tbl_index[slot];
+ cache_inode = snap_get_indirect(inode, NULL, index);
+
+ if ( !cache_inode ) continue;
+
+ if (cache_inode->i_op->bmap(cache_inode, block[i])) {
+ CDEBUG(D_FILE, "find cache_ino %lu\n",
+ cache_inode->i_ino);
+ if( snapops && snapops->copy_block) {
+ snapops->copy_block( inode,
+ cache_inode, block[i]);
+ }
+
+ iput(cache_inode);
+ break;
+ }
+ iput(cache_inode);
+ }
+ }
+ }
+
+ rc = fops->write(filp, buf, count, ppos);
+
+ EXIT;
+ return rc;
+}
+
+static int currentfs_readpage(struct file *file, struct page *page)
+{
+ int result = 0;
+ struct inode *inode = file->f_dentry->d_inode;
+ unsigned long ind_ino = inode->i_ino;
+ struct inode *pri_inode = NULL;
+ struct inode *cache_inode = NULL;
+ struct file open_file;
+ struct dentry open_dentry ;
+ struct inode_operations *ciops;
+ struct snap_cache *cache;
+ long block;
+ struct snap_table *table;
+ int slot = 0;
+ int index = 0;
+ int search_older = 0;
+
+ ENTRY;
+
+ cache = snap_find_cache(inode->i_dev);
+ if ( !cache ) {
+ EXIT;
+ return -EINVAL;
+ }
+
+ ciops = filter_c2cfiops(cache->cache_filter);
+
+ block = page->offset >> inode->i_sb->s_blocksize_bits;
+
+ /* if there is a block in the cache, return the cache readpage */
+ if( inode->i_blocks && ciops->bmap(inode, block) ) {
+ CDEBUG(D_FILE, "block %lu in cache, ino %lu\n",
+ block, inode->i_ino);
+ result = ciops->readpage(file, page);
+ EXIT;
+ return result;
+ }
+
+ /*
+ * clonefs_readpage will fill this with primary ino number
+ * we need it to follow the cloned chain of primary inode
+ */
+ if( file->f_dentry->d_fsdata ){
+ pri_inode = iget(inode->i_sb, (unsigned long)file->f_dentry->d_fsdata);
+ if( !pri_inode )
+ return -EINVAL;
+ inode = pri_inode;
+ search_older = 1;
+ }
+
+ table = &snap_tables[cache->cache_snap_tableno];
+
+ for (slot = table->tbl_count ; slot >= 1; slot--)
+ {
+ cache_inode = NULL;
+ index = table->tbl_index[slot];
+ cache_inode = snap_get_indirect(inode, NULL, index);
+
+ if ( !cache_inode ) continue;
+
+ /* we only want slots between cache_inode to the oldest one */
+ if( search_older && cache_inode->i_ino == ind_ino )
+ search_older = 0;
+
+ if ( !search_older && cache_inode->i_op->bmap(cache_inode, block)) {
+ break;
+ }
+ iput(cache_inode);
+ }
+ if( pri_inode )
+ iput(pri_inode);
+
+ if ( !cache_inode ) {
+ EXIT;
+ return -EINVAL;
+ }
+
+ currentfs_prepare_snapfile(inode, file, cache_inode, &open_file,
+ &open_dentry);
+
+ down(&cache_inode->i_sem);
+
+ if( ciops->readpage ) {
+ CDEBUG(D_FILE, "block %lu NOT in cache, use redirected ino %lu\n", block, cache_inode->i_ino );
+ result = ciops->readpage(&open_file, page);
+ }else {
+ CDEBUG(D_FILE, "cache ino %lu, readpage is NULL\n",
+ cache_inode->i_ino);
+ }
+
+ up(&cache_inode->i_sem);
+ currentfs_restore_snapfile(inode, file, cache_inode, &open_file);
+ iput(cache_inode);
+ EXIT;
+ return result;
+}
+
+struct file_operations currentfs_file_fops = {
+ write:currentfs_write,
+};
+
+struct inode_operations currentfs_file_iops = {
+ default_file_ops: ¤tfs_file_fops,
+ readpage: currentfs_readpage,
+};
diff --git a/lustre/snapfs/filter.c b/lustre/snapfs/filter.c
new file mode 100644
index 0000000000..c63caac5cd
--- /dev/null
+++ b/lustre/snapfs/filter.c
@@ -0,0 +1,433 @@
+/*
+ *
+ *
+ * Copyright (C) 2000 Stelias Computing, Inc.
+ * Copyright (C) 2000 Red Hat, Inc.
+ * Copyright (C) 2000 Mountain View Data, Inc.
+ *
+ *
+ */
+
+#include <stdarg.h>
+
+#include <asm/bitops.h>
+#include <asm/uaccess.h>
+#include <asm/system.h>
+
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/ext2_fs.h>
+#include <linux/malloc.h>
+#include <linux/vmalloc.h>
+#include <linux/sched.h>
+#include <linux/stat.h>
+#include <linux/string.h>
+#include <linux/locks.h>
+#include <linux/blkdev.h>
+#include <linux/init.h>
+#define __NO_VERSION__
+#include <linux/module.h>
+
+#include <linux/filter.h>
+
+int filter_print_entry = 1;
+int filter_debug = 0xfffffff;
+/*
+ * The function in this file are responsible for setting up the
+ * correct methods layered file systems like InterMezzo and SnapFS
+ */
+
+
+static struct filter_fs filter_oppar[FILTER_FS_TYPES];
+
+/* get to the upper methods (intermezzo, snapfs) */
+inline struct super_operations *filter_c2usops(struct filter_fs *cache)
+{
+ return &cache->o_fops.filter_sops;
+}
+
+inline struct inode_operations *filter_c2udiops(struct filter_fs *cache)
+{
+ return &cache->o_fops.filter_dir_iops;
+}
+
+inline struct inode_operations *filter_c2ufiops(struct filter_fs *cache)
+{
+ return &cache->o_fops.filter_file_iops;
+}
+
+inline struct inode_operations *filter_c2usiops(struct filter_fs *cache)
+{
+ return &cache->o_fops.filter_sym_iops;
+}
+
+inline struct file_operations *filter_c2udfops(struct filter_fs *cache)
+{
+ return &cache->o_fops.filter_dir_fops;
+}
+
+inline struct file_operations *filter_c2uffops(struct filter_fs *cache)
+{
+ return &cache->o_fops.filter_file_fops;
+}
+
+inline struct file_operations *filter_c2usfops(struct filter_fs *cache)
+{
+ return &cache->o_fops.filter_sym_fops;
+}
+
+inline struct dentry_operations *filter_c2udops(struct filter_fs *cache)
+{
+ return &cache->o_fops.filter_dentry_ops;
+}
+
+/* get to the cache (lower) methods */
+inline struct super_operations *filter_c2csops(struct filter_fs *cache)
+{
+ return cache->o_caops.cache_sops;
+}
+
+inline struct inode_operations *filter_c2cdiops(struct filter_fs *cache)
+{
+ return cache->o_caops.cache_dir_iops;
+}
+
+inline struct inode_operations *filter_c2cfiops(struct filter_fs *cache)
+{
+ return cache->o_caops.cache_file_iops;
+}
+
+inline struct inode_operations *filter_c2csiops(struct filter_fs *cache)
+{
+ return cache->o_caops.cache_sym_iops;
+}
+
+inline struct file_operations *filter_c2cdfops(struct filter_fs *cache)
+{
+ return cache->o_caops.cache_dir_fops;
+}
+
+inline struct file_operations *filter_c2cffops(struct filter_fs *cache)
+{
+ return cache->o_caops.cache_file_fops;
+}
+
+inline struct file_operations *filter_c2csfops(struct filter_fs *cache)
+{
+ return cache->o_caops.cache_sym_fops;
+}
+
+inline struct dentry_operations *filter_c2cdops(struct filter_fs *cache)
+{
+ return cache->o_caops.cache_dentry_ops;
+}
+/* snapfs: for snapshot operations */
+inline struct snapshot_operations *filter_c2csnapops(struct filter_fs *cache)
+{
+ return cache->o_snapops;
+}
+
+/* find the cache for this FS */
+struct filter_fs *filter_get_filter_fs(const char *cache_type)
+{
+ struct filter_fs *ops = NULL;
+ FENTRY;
+
+ if ( strlen(cache_type) == strlen("ext2") &&
+ memcmp(cache_type, "ext2", strlen("ext2")) == 0 ) {
+ ops = &filter_oppar[FILTER_FS_EXT2];
+ FDEBUG(D_SUPER, "ops at %p\n", ops);
+ }
+
+ if ( strlen(cache_type) == strlen("ext3") &&
+ memcmp(cache_type, "ext3", strlen("ext3")) == 0 ) {
+ ops = &filter_oppar[FILTER_FS_EXT3];
+ FDEBUG(D_SUPER, "ops at %p\n", ops);
+ }
+ if ( strlen(cache_type) == strlen("reiser") &&
+ memcmp(cache_type, "reiser", strlen("reiser")) == 0 ) {
+ ops = &filter_oppar[FILTER_FS_REISER];
+ FDEBUG(D_SUPER, "ops at %p\n", ops);
+ }
+
+ if (ops == NULL) {
+ printk("prepare to die: unrecognized cache type for Filter\n");
+ }
+ FEXIT;
+ return ops;
+}
+
+
+/*
+ * Frobnicate the InterMezzo/SnapFS operations
+ * this establishes the link between the InterMezzo/SnapFS file system
+ * and the underlying file system used for the cache.
+ */
+
+void filter_setup_super_ops(struct filter_fs *cache, struct super_operations *cache_sops, struct super_operations *filter_sops)
+{
+ /* Get ptr to the shared struct snapfs_ops structure. */
+ struct filter_ops *uops = &cache->o_fops;
+ /* Get ptr to the shared struct cache_ops structure. */
+ struct cache_ops *caops = &cache->o_caops;
+
+ FENTRY;
+
+ if ( cache->o_flags & FILTER_DID_SUPER_OPS ) {
+ FEXIT;
+ return;
+ }
+ cache->o_flags |= FILTER_DID_SUPER_OPS;
+
+ /* Set the cache superblock operations to point to the
+ superblock operations of the underlying file system. */
+ caops->cache_sops = cache_sops;
+
+ /*
+ * Copy the cache (real fs) superblock ops to the "filter"
+ * superblock ops as defaults. Some will be changed below
+ */
+ memcpy(&uops->filter_sops, cache_sops, sizeof(*cache_sops));
+
+ /* now overwrite with filtering ops */
+ if (cache_sops->put_super && uops->filter_sops.put_super) {
+ uops->filter_sops.put_super = filter_sops->put_super;
+ }
+ if (cache_sops->read_inode && uops->filter_sops.read_inode) {
+ uops->filter_sops.read_inode = filter_sops->read_inode;
+ FDEBUG(D_INODE, "setting filter_read_inode, cache_ops %p, cache %p, ri at %p\n",
+ cache, cache, uops->filter_sops.read_inode);
+ }
+ if (cache_sops->notify_change && uops->filter_sops.notify_change)
+ uops->filter_sops.notify_change = filter_sops->notify_change;
+ if (cache_sops->remount_fs && uops->filter_sops.remount_fs)
+ uops->filter_sops.remount_fs = filter_sops->remount_fs;
+ FEXIT;
+}
+
+
+void filter_setup_dir_ops(struct filter_fs *cache, struct inode_operations *cache_iops, struct inode_operations *filter_iops)
+{
+ struct inode_operations *u_iops;
+ struct file_operations *u_fops, *c_fops, *f_fops;
+ FENTRY;
+
+ if ( cache->o_flags & FILTER_DID_DIR_OPS ) {
+ FEXIT;
+ return;
+ }
+ FDEBUG(D_SUPER, "\n");
+ cache->o_flags |= FILTER_DID_DIR_OPS;
+
+ /* steal the old ops */
+ cache->o_caops.cache_dir_iops = cache_iops;
+ cache->o_caops.cache_dir_fops =
+ cache_iops->default_file_ops;
+
+ FDEBUG(D_SUPER, "\n");
+ /* abbreviate */
+ u_iops = &cache->o_fops.filter_dir_iops;
+
+ /* setup our dir iops: copy and modify */
+ memcpy(u_iops, cache_iops, sizeof(*cache_iops));
+ FDEBUG(D_SUPER, "\n");
+
+ /* methods that filter if cache filesystem has these ops */
+ if ( cache_iops->lookup && filter_iops->lookup ) {
+ FDEBUG(D_SUPER, "\n");
+ u_iops->lookup = filter_iops->lookup;
+ FDEBUG(D_SUPER, "lookup at %p\n", &filter_iops->lookup);
+ }
+ if (cache_iops->create && filter_iops->create)
+ u_iops->create = filter_iops->create;
+ FDEBUG(D_SUPER, "\n");
+ if (cache_iops->link && filter_iops->link)
+ u_iops->link = filter_iops->link;
+ FDEBUG(D_SUPER, "\n");
+ if (cache_iops->unlink && filter_iops->unlink)
+ u_iops->unlink = filter_iops->unlink;
+ FDEBUG(D_SUPER, "\n");
+ if (cache_iops->mkdir && filter_iops->mkdir)
+ u_iops->mkdir = filter_iops->mkdir;
+ FDEBUG(D_SUPER, "\n");
+ if (cache_iops->rmdir && filter_iops->rmdir)
+ u_iops->rmdir = filter_iops->rmdir;
+ FDEBUG(D_SUPER, "\n");
+ if (cache_iops->symlink && filter_iops->symlink)
+ u_iops->symlink = filter_iops->symlink;
+ FDEBUG(D_SUPER, "\n");
+ if (cache_iops->rename && filter_iops->rename)
+ u_iops->rename = filter_iops->rename;
+ FDEBUG(D_SUPER, "\n");
+ if (cache_iops->mknod && filter_iops->mknod)
+ u_iops->mknod = filter_iops->mknod;
+ FDEBUG(D_SUPER, "\n");
+ if (cache_iops->permission && filter_iops->permission)
+ u_iops->permission = filter_iops->permission;
+
+ /* copy dir fops */
+ FDEBUG(D_SUPER, "\n");
+ u_fops = &cache->o_fops.filter_dir_fops;
+ c_fops = cache_iops->default_file_ops;
+ f_fops = filter_iops->default_file_ops;
+
+ memcpy(u_fops, c_fops, sizeof(*c_fops));
+
+ if( c_fops->readdir && f_fops->readdir )
+ u_fops->readdir = f_fops->readdir;
+
+ /* assign */
+ FDEBUG(D_SUPER, "\n");
+ filter_c2udiops(cache)->default_file_ops = filter_c2udfops(cache);
+ FDEBUG(D_SUPER, "\n");
+
+ /* unconditional filtering operations */
+ if ( filter_iops->default_file_ops &&
+ filter_iops->default_file_ops->open )
+ filter_c2udfops(cache)->open =
+ filter_iops->default_file_ops->open;
+
+ FEXIT;
+}
+
+
+void filter_setup_file_ops(struct filter_fs *cache, struct inode_operations *cache_iops, struct inode_operations *filter_iops)
+{
+ struct inode_operations *u_iops;
+ FENTRY;
+
+ if ( cache->o_flags & FILTER_DID_FILE_OPS ) {
+ FEXIT;
+ return;
+ }
+ cache->o_flags |= FILTER_DID_FILE_OPS;
+
+ /* steal the old ops */
+ cache->o_caops.cache_file_iops = cache_iops;
+ cache->o_caops.cache_file_fops =
+ cache_iops->default_file_ops;
+
+ /* abbreviate */
+ u_iops = filter_c2ufiops(cache);
+
+ /* setup our dir iops: copy and modify */
+ memcpy(u_iops, cache_iops, sizeof(*cache_iops));
+
+ /* copy dir fops */
+ memcpy(filter_c2uffops(cache), cache_iops->default_file_ops,
+ sizeof(*cache_iops->default_file_ops));
+ /* assign */
+ filter_c2ufiops(cache)->default_file_ops = filter_c2uffops(cache);
+
+ /* unconditional filtering operations */
+ if (filter_iops->default_file_ops &&
+ filter_iops->default_file_ops->open )
+ filter_c2uffops(cache)->open =
+ filter_iops->default_file_ops->open;
+ if (filter_iops->default_file_ops &&
+ filter_iops->default_file_ops->release )
+ filter_c2uffops(cache)->release =
+ filter_iops->default_file_ops->release;
+ if (filter_iops->default_file_ops &&
+ filter_iops->default_file_ops->write )
+ filter_c2uffops(cache)->write =
+ filter_iops->default_file_ops->write;
+
+ /* set up readpage */
+ if (filter_iops->readpage)
+ filter_c2ufiops(cache)->readpage = filter_iops->readpage;
+
+ FEXIT;
+}
+
+/* XXX in 2.3 there are "fast" and "slow" symlink ops for ext2 XXX */
+void filter_setup_symlink_ops(struct filter_fs *cache, struct inode_operations *cache_iops, struct inode_operations *filter_iops)
+{
+ struct inode_operations *u_iops;
+ FENTRY;
+
+ if ( cache->o_flags & FILTER_DID_SYMLINK_OPS ) {
+ FEXIT;
+ return;
+ }
+ cache->o_flags |= FILTER_DID_SYMLINK_OPS;
+
+ /* steal the old ops */
+ cache->o_caops.cache_sym_iops = cache_iops;
+ cache->o_caops.cache_sym_fops =
+ cache_iops->default_file_ops;
+
+ /* abbreviate */
+ u_iops = filter_c2usiops(cache);
+
+ /* setup our dir iops: copy and modify */
+ memcpy(u_iops, cache_iops, sizeof(*cache_iops));
+
+ /* copy fops - careful for symlinks they might be NULL */
+ if ( cache_iops->default_file_ops ) {
+ memcpy(filter_c2usfops(cache), cache_iops->default_file_ops,
+ sizeof(*cache_iops->default_file_ops));
+ }
+
+ /* assign */
+ filter_c2usiops(cache)->default_file_ops = filter_c2usfops(cache);
+
+ if (cache_iops->readlink && filter_iops->readlink)
+ u_iops->readlink = filter_iops->readlink;
+ if (cache_iops->follow_link && filter_iops->follow_link)
+ u_iops->follow_link = filter_iops->follow_link;
+
+ FEXIT;
+}
+
+void filter_setup_dentry_ops(struct filter_fs *cache,
+ struct dentry_operations *cache_dop,
+ struct dentry_operations *filter_dop)
+{
+ if ( cache->o_flags & FILTER_DID_DENTRY_OPS ) {
+ FEXIT;
+ return;
+ }
+ cache->o_flags |= FILTER_DID_DENTRY_OPS;
+
+ cache->o_caops.cache_dentry_ops = cache_dop;
+ memcpy(&cache->o_fops.filter_dentry_ops,
+ filter_dop, sizeof(*filter_dop));
+
+ if (cache_dop && cache_dop != filter_dop && cache_dop->d_revalidate){
+ printk("WARNING: filter overriding revalidation!\n");
+ }
+ return;
+}
+/* snapfs : for snapshot operations */
+void filter_setup_snapshot_ops (struct filter_fs *cache,
+ struct snapshot_operations *cache_snapops)
+{
+ FENTRY;
+
+ if ( cache->o_flags & FILTER_DID_SNAPSHOT_OPS ) {
+ FEXIT;
+ return;
+ }
+ cache->o_flags |= FILTER_DID_SNAPSHOT_OPS;
+
+ cache->o_snapops = cache_snapops;
+
+ FEXIT;
+}
+
+void filter_setup_journal_ops (struct filter_fs *cache,
+ struct journal_ops *cache_journal_ops)
+{
+ FENTRY;
+
+ if( cache->o_flags & FILTER_DID_JOURNAL_OPS ){
+ FEXIT;
+ return;
+ }
+ cache->o_flags |= FILTER_DID_JOURNAL_OPS;
+
+ cache->o_trops = cache_journal_ops;
+
+ FEXIT;
+}
diff --git a/lustre/snapfs/inode.c b/lustre/snapfs/inode.c
new file mode 100644
index 0000000000..d6434f3540
--- /dev/null
+++ b/lustre/snapfs/inode.c
@@ -0,0 +1,211 @@
+/*
+ * fs/snap/snap.c
+ *
+ * A snap shot file system.
+ *
+ */
+
+#define EXPORT_SYMTAB
+
+
+#define __NO_VERSION__
+#include <linux/module.h>
+#include <asm/uaccess.h>
+#include <linux/sched.h>
+#include <linux/stat.h>
+#include <linux/string.h>
+#include <linux/locks.h>
+#include <linux/quotaops.h>
+#include <linux/list.h>
+#include <linux/file.h>
+#include <asm/bitops.h>
+#include <asm/byteorder.h>
+
+#ifdef CONFIG_SNAPFS_EXT2
+#include <linux/ext2_fs.h>
+#endif
+#ifdef CONFIG_SNAPFS_EXT3
+#include <linux/ext3_fs.h>
+#endif
+
+#include <linux/filter.h>
+#include <linux/snapfs.h>
+#include <linux/snapsupport.h>
+
+
+extern int currentfs_remount(struct super_block * sb, int *flags, char *data);
+
+/* XXX PJB: this is exactly what we need to put things under
+ filters - we don't want the ext2 methods hardcoded, we want them
+ in the filter (in read_super) and then call those methods.
+ See how InterMezzo gets the journal operations .
+*/
+
+extern void currentfs_dotsnap_read_inode(struct snap_cache *, struct inode *);
+
+/* Superblock operations. */
+static void currentfs_read_inode(struct inode *inode)
+{
+ struct snap_cache *cache;
+ ENTRY;
+
+ if( !inode )
+ {
+ EXIT;
+ return;
+ }
+
+ CDEBUG(D_INODE, "read_inode ino %lu\n", inode->i_ino);
+
+ cache = snap_find_cache(inode->i_dev);
+ if ( !cache ) {
+ printk("currentfs_read_inode: cannot find cache\n");
+ make_bad_inode(inode);
+ EXIT;
+ return ;
+ }
+
+ if ( inode->i_ino & 0xF0000000 ) {
+ CDEBUG(D_INODE, "\n");
+ currentfs_dotsnap_read_inode(cache, inode);
+ EXIT;
+ return ;
+ }
+
+ if( filter_c2csops(cache->cache_filter) )
+ filter_c2csops(cache->cache_filter)->read_inode(inode);
+
+ /* XXX now set the correct snap_{file,dir,sym}_iops */
+ if ( S_ISDIR(inode->i_mode) )
+ inode->i_op = filter_c2udiops(cache->cache_filter);
+ else if ( S_ISREG(inode->i_mode) ) {
+ if ( !filter_c2cfiops(cache->cache_filter) ) {
+ filter_setup_file_ops(cache->cache_filter,
+ inode->i_op, ¤tfs_file_iops);
+ }
+ inode->i_op = filter_c2ufiops(cache->cache_filter);
+ printk("inode %lu, i_op at %p\n", inode->i_ino, inode->i_op);
+ }
+ else if ( S_ISLNK(inode->i_mode) ) {
+ if ( !filter_c2csiops(cache->cache_filter) ) {
+ filter_setup_symlink_ops(cache->cache_filter,
+ inode->i_op, ¤tfs_sym_iops);
+ }
+ inode->i_op = filter_c2usiops(cache->cache_filter);
+ printk("inode %lu, i_op at %p\n", inode->i_ino, inode->i_op);
+ }
+
+ EXIT;
+ return;
+}
+
+
+static int currentfs_notify_change(struct dentry *dentry, struct iattr *iattr)
+{
+ struct snap_cache *cache;
+ int rc;
+ struct super_operations *sops;
+
+ ENTRY;
+
+ if (currentfs_is_under_dotsnap(dentry)) {
+ EXIT;
+ return -EPERM;
+ }
+
+ cache = snap_find_cache(dentry->d_inode->i_dev);
+ if ( !cache ) {
+ EXIT;
+ return -EINVAL;
+ }
+
+ /* XXX better alloc a new dentry */
+
+ if ( snap_needs_cow(dentry->d_inode) != -1 ) {
+ printk("notify_change:snap_needs_cow for ino %lu \n",
+ dentry->d_inode->i_ino);
+ snap_do_cow(dentry->d_inode,
+ dentry->d_parent->d_inode->i_ino, 0);
+ }
+
+ sops = filter_c2csops(cache->cache_filter);
+ if (!sops ||
+ !sops->notify_change) {
+ EXIT;
+ return -EINVAL;
+ }
+ rc = sops->notify_change(dentry, iattr);
+
+ EXIT;
+ return rc;
+}
+
+
+static void currentfs_put_super(struct super_block *sb)
+{
+
+ struct snap_cache *cache;
+ ENTRY;
+
+ CDEBUG(D_SUPER, "sb %lx, sb->u.generic_sbp: %lx\n",
+ (ulong) sb, (ulong) sb->u.generic_sbp);
+ cache = snap_find_cache(sb->s_dev);
+ if (!cache) {
+ EXIT;
+ goto exit;
+ }
+ /* handle COMPAT_FEATUREs */
+#ifdef CONFIG_SNAPFS_EXT2
+ else if( cache->cache_type == FILTER_FS_EXT2 ){
+ if( !EXT2_HAS_COMPAT_FEATURE(sb, EXT2_FEATURE_COMPAT_SNAPFS) ){
+ sb->u.ext2_sb.s_feature_compat &=
+ ~EXT2_FEATURE_COMPAT_BLOCKCOW;
+ sb->u.ext2_sb.s_es->s_feature_compat &=
+ cpu_to_le32(~EXT2_FEATURE_COMPAT_BLOCKCOW);
+ }
+ }
+#endif
+#ifdef CONFIG_SNAPFS_EXT3
+ else if( cache->cache_type == FILTER_FS_EXT3 ){
+ if( !EXT3_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_SNAPFS) ){
+ sb->u.ext3_sb.s_es->s_feature_compat &=
+ cpu_to_le32(~EXT3_FEATURE_COMPAT_BLOCKCOW);
+ }
+ }
+#endif
+ /*
+ * If there is a saved 'put_super' function for the underlying
+ * fs then call it.
+ */
+ if (cache->cache_filter->o_caops.cache_sops->put_super) {
+ cache->cache_filter->o_caops.cache_sops->put_super(sb);
+ }
+
+ if (!list_empty(&cache->cache_clone_list)) {
+ printk("Warning: snap_put_super: clones exist!\n");
+ }
+
+ list_del(&cache->cache_chain);
+ snap_free_cache(cache);
+
+ CDEBUG(D_SUPER, "sb %lx, sb->u.generic_sbp: %lx\n",
+ (ulong) sb, (ulong) sb->u.generic_sbp);
+exit:
+ CDEBUG(D_MALLOC, "after umount: kmem %ld, vmem %ld\n",
+ snap_kmemory, snap_vmemory);
+ MOD_DEC_USE_COUNT;
+ EXIT;
+ return ;
+}
+
+struct super_operations currentfs_super_ops = {
+ currentfs_read_inode,
+ NULL, /* write inode */
+ NULL, /* put inode */
+ NULL, /* delete inode */
+ currentfs_notify_change,
+ currentfs_put_super,
+ NULL, /* write super */
+ NULL,
+ NULL, /* remount */
+};
diff --git a/lustre/snapfs/journal_ext3.c b/lustre/snapfs/journal_ext3.c
new file mode 100644
index 0000000000..8171842e53
--- /dev/null
+++ b/lustre/snapfs/journal_ext3.c
@@ -0,0 +1,84 @@
+
+/*
+ * Snapfs. (C) 2000 Peter J. Braam
+ */
+
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/fs.h>
+#include <linux/malloc.h>
+#include <linux/vmalloc.h>
+#include <linux/stat.h>
+#include <linux/errno.h>
+#include <linux/locks.h>
+#include <asm/segment.h>
+#include <asm/uaccess.h>
+#include <linux/string.h>
+#ifdef CONFIG_SNAPFS_EXT3
+#include <linux/ext3_jfs.h>
+#endif
+#include "linux/filter.h"
+#include "linux/snapfs.h"
+#include "linux/snapsupport.h"
+
+#ifdef CONFIG_SNAPFS_EXT3
+
+#define EXT3_EA_TRANS_BLOCKS EXT3_DATA_TRANS_BLOCKS
+
+/*
+ * must follow the changes of ext3_create_indirect() in fs/ext3/snap.c
+ */
+#define COW_CREDITS (2 * EXT3_EA_TRANS_BLOCKS + 17 + 2 * EXT3_DATA_TRANS_BLOCKS )
+
+/* start the filesystem journal operations */
+static void *snap_e3_trans_start(struct inode *inode, int op)
+{
+ int jblocks;
+
+ /* XXX needs to be fixed up when we get reiserfs support */
+ switch (op) {
+ case SNAP_OP_CREATE:
+ jblocks = COW_CREDITS + EXT3_DATA_TRANS_BLOCKS + 3;
+ break;
+ case SNAP_OP_LINK:
+ jblocks = COW_CREDITS + EXT3_DATA_TRANS_BLOCKS;
+ break;
+ case SNAP_OP_UNLINK:
+ jblocks = COW_CREDITS + EXT3_DELETE_TRANS_BLOCKS;
+ break;
+ case SNAP_OP_SYMLINK:
+ jblocks = COW_CREDITS + EXT3_DATA_TRANS_BLOCKS + 5;
+ break;
+ case SNAP_OP_MKDIR:
+ jblocks = COW_CREDITS + EXT3_DATA_TRANS_BLOCKS + 4;
+ break;
+ case SNAP_OP_RMDIR:
+ jblocks = 2 * COW_CREDITS + EXT3_DELETE_TRANS_BLOCKS;
+ break;
+ case SNAP_OP_MKNOD:
+ jblocks = COW_CREDITS + EXT3_DATA_TRANS_BLOCKS + 3;
+ break;
+ case SNAP_OP_RENAME:
+ jblocks = 4 * COW_CREDITS + 2 * EXT3_DATA_TRANS_BLOCKS + 2;
+ break;
+ default:
+ CDEBUG(D_JOURNAL, "invalid operation %d for journal\n", op);
+ return NULL;
+ }
+
+ CDEBUG(D_JOURNAL, "creating journal handle (%d blocks)\n", jblocks);
+ return journal_start(EXT3_JOURNAL(inode), jblocks);
+}
+
+static void snap_e3_trans_commit(void *handle)
+{
+ journal_stop(current->j_handle);
+}
+
+struct journal_ops snap_ext3_journal_ops = {
+ snap_e3_trans_start,
+ snap_e3_trans_commit
+};
+
+#endif /* CONFIG_EXT3_FS */
diff --git a/lustre/snapfs/psdev.c b/lustre/snapfs/psdev.c
new file mode 100644
index 0000000000..424d32557d
--- /dev/null
+++ b/lustre/snapfs/psdev.c
@@ -0,0 +1,180 @@
+/*
+ * A file system filter driver in the style of InterMezzo
+ * to manage file system snapshots
+ *
+ * Author: Peter J. Braam <braam@mountainviewdata.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#define EXPORT_SYMTAB
+
+#include <linux/config.h> /* for CONFIG_PROC_FS */
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/major.h>
+/* #include <linux/kmod.h> for request_module() */
+#include <linux/sched.h>
+#include <linux/lp.h>
+#include <linux/malloc.h>
+#include <linux/ioport.h>
+#include <linux/fcntl.h>
+#include <linux/delay.h>
+#include <linux/skbuff.h>
+#include <linux/proc_fs.h>
+#include <linux/vmalloc.h>
+#include <linux/fs.h>
+#include <linux/poll.h>
+#include <linux/init.h>
+#include <linux/list.h>
+#include <asm/io.h>
+#include <asm/segment.h>
+#include <asm/system.h>
+#include <asm/poll.h>
+#include <asm/uaccess.h>
+#include <linux/miscdevice.h>
+
+#include <linux/filter.h>
+#include <linux/snapfs.h>
+#include <linux/snapsupport.h>
+
+#if 1 /* XXX - enable for debug messages */
+int snap_print_entry = 1;
+int snap_debug_level = ~D_INFO;
+#else
+int snap_print_entry = 0;
+int snap_debug_level = 0;
+#endif
+int snap_inodes = 0;
+long snap_memory = 0;
+
+struct snap_control_device snap_dev;
+
+extern int snap_ioctl (struct inode * inode, struct file * filp,
+ unsigned int cmd, unsigned long arg);
+
+/* called when opening /dev/device */
+static int snap_psdev_open(struct inode * inode, struct file * file)
+{
+ int dev;
+ ENTRY;
+
+ if (!inode)
+ return -EINVAL;
+ dev = MINOR(inode->i_rdev);
+ if (dev != SNAP_PSDEV_MINOR)
+ return -ENODEV;
+
+ MOD_INC_USE_COUNT;
+ EXIT;
+ return 0;
+}
+
+/* called when closing /dev/device */
+static int snap_psdev_release(struct inode * inode, struct file * file)
+{
+ int dev;
+ ENTRY;
+
+ if (!inode)
+ return -EINVAL;
+ dev = MINOR(inode->i_rdev);
+ if (dev != SNAP_PSDEV_MINOR)
+ return -ENODEV;
+
+ MOD_DEC_USE_COUNT;
+
+ EXIT;
+ return 0;
+}
+
+/* XXX need ioctls here to do snap_delete and snap_restore, snap_backup */
+
+
+/* declare character device */
+static struct file_operations snapcontrol_fops = {
+ NULL, /* llseek */
+ NULL, /* read */
+ NULL, /* write */
+ NULL, /* presto_psdev_readdir */
+ NULL, /* poll */
+ snap_ioctl, /* ioctl */
+ NULL, /* presto_psdev_mmap */
+ snap_psdev_open, /* open */
+ NULL,
+ snap_psdev_release, /* release */
+ NULL, /* fsync */
+ NULL, /* fasync */
+ NULL /* lock */
+};
+
+
+
+#define SNAPFS_MINOR 240
+
+static struct miscdevice snapcontrol_dev = {
+ SNAPFS_MINOR,
+ "snapcontrol",
+ &snapcontrol_fops
+};
+
+int init_snap_psdev(void)
+{
+ printk(KERN_INFO "SNAP psdev driver v0.01, braam@mountainviewdata.com\n");
+
+ misc_register( &snapcontrol_dev );
+
+ return 0;
+}
+
+void snap_cleanup_psdev(void)
+{
+ ENTRY;
+ misc_deregister(&snapcontrol_dev);
+ EXIT;
+}
+
+#ifdef MODULE
+MODULE_AUTHOR("Peter J. Braam <braam@cs.cmu.edu>");
+MODULE_DESCRIPTION("Snapfs file system filters v0.01");
+
+extern int init_snapfs(void);
+extern int cleanup_snapfs(void);
+extern int init_clonefs(void);
+extern int init_snap_sysctl(void);
+
+int init_module(void)
+{
+ int err;
+ if ( (err = init_snap_psdev()) ) {
+ printk("Error initializing snap_psdev, %d\n", err);
+ return -EINVAL;
+ }
+
+ if ( (err = init_snapfs()) ) {
+ printk("Error initializing snapfs, %d\n", err);
+ return -EINVAL;
+ }
+
+ if ( (err = init_snapfs_proc_sys()) ) {
+ printk("Error initializing snapfs proc sys, %d\n", err);
+ return -EINVAL;
+ }
+
+
+ return 0;
+}
+
+void cleanup_module(void)
+{
+
+ cleanup_snapfs();
+ snap_cleanup_psdev();
+
+}
+#endif
+
diff --git a/lustre/snapfs/snap.c b/lustre/snapfs/snap.c
new file mode 100644
index 0000000000..463e0faae7
--- /dev/null
+++ b/lustre/snapfs/snap.c
@@ -0,0 +1,278 @@
+
+/*
+ * fs/snap/snap.c
+ *
+ * A snap shot file system.
+ *
+ */
+
+#define EXPORT_SYMTAB
+
+
+#define __NO_VERSION__
+#include <linux/module.h>
+#include <asm/uaccess.h>
+#include <linux/sched.h>
+#include <linux/stat.h>
+#include <linux/string.h>
+#include <linux/locks.h>
+#include <linux/quotaops.h>
+#include <linux/list.h>
+#include <linux/file.h>
+#include <asm/bitops.h>
+#include <asm/byteorder.h>
+
+#include <linux/filter.h>
+#include <linux/snapfs.h>
+#include <linux/snapsupport.h>
+
+/*
+ * Return true if the inode is a redirector inode.
+ */
+int snap_is_redirector(struct inode *cache_inode)
+{
+ struct snap_cache *cache;
+ struct snapshot_operations *snapops;
+
+ cache = snap_find_cache(cache_inode->i_dev);
+ if (!cache) {
+ EXIT;
+ return 0;
+ }
+ snapops = filter_c2csnapops(cache->cache_filter);
+ if (!snapops || !snapops->is_redirector) {
+ EXIT;
+ return 0;
+ }
+
+ CDEBUG(D_SNAP, "ino %ld\n", cache_inode->i_ino);
+ return snapops->is_redirector(cache_inode);
+}
+
+/*
+ * Using a cache inode and clone super block find the real one.
+ */
+struct inode *snap_redirect(struct inode *cache_inode,
+ struct super_block *clone_sb)
+{
+ struct snap_clone_info *clone_info;
+ struct snap_table *table;
+ struct inode *redirected;
+ struct snap_cache *cache;
+ struct snapshot_operations *snapops;
+ int slot = 0;
+ int my_table[SNAP_MAX];
+ int clone_slot;
+
+ ENTRY;
+
+ cache = snap_find_cache(cache_inode->i_dev);
+ if (!cache) {
+ EXIT;
+ return NULL;
+ }
+ snapops = filter_c2csnapops(cache->cache_filter);
+ if (!snapops || !snapops->get_indirect) {
+ EXIT;
+ return NULL;
+ }
+
+ CDEBUG(D_SNAP, "cache ino %ld\n", cache_inode->i_ino);
+ clone_info = (struct snap_clone_info *)&clone_sb->u.generic_sbp;
+
+ table = &snap_tables[clone_info->clone_cache->cache_snap_tableno];
+
+ /* first find if there are indirected at the clone_index */
+ redirected = snapops->get_indirect(cache_inode, NULL,
+ clone_info->clone_index);
+ /* if not found, get the FIRST index after this and before NOW */
+ /* XXX fix this later, now use tbl_count, not NOW */
+ if(!redirected) {
+ clone_slot = snap_index2slot(table, clone_info->clone_index);
+ for(slot = table->tbl_count; slot >= clone_slot; slot --)
+ {
+ my_table[slot-clone_slot+1] = table->tbl_index[slot];
+ }
+ redirected = snapops->get_indirect
+ (cache_inode, my_table, table->tbl_count - clone_slot + 1);
+ }
+ /* old version
+ redirected = snapops->get_indirect
+ (cache_inode, table->tbl_index,
+ snap_index2slot(table, clone_info->clone_index));
+ */
+ if(redirected) CDEBUG(D_SNAP,"redirected ino %ld\n",redirected->i_ino);
+ EXIT;
+ return redirected;
+}
+
+/*
+ * Make a copy of the data and plug a redirector in between if there
+ * is no redirector yet.
+ */
+int snap_do_cow(struct inode *inode, ino_t parent_ino, int del)
+{
+ struct snap_cache *cache;
+ struct snap snap;
+ struct inode *ind = NULL;
+ struct snapshot_operations *snapops;
+
+ ENTRY;
+ CDEBUG(D_SNAP, "snap_do_cow, ino %ld\n", inode->i_ino);
+
+ cache = snap_find_cache(inode->i_dev);
+ if (!cache) {
+ EXIT;
+ return -EINVAL;
+ }
+ snapops = filter_c2csnapops(cache->cache_filter);
+ if (!snapops || !snapops->create_indirect) {
+ EXIT;
+ return -EINVAL;
+ }
+ snap_last(cache, &snap);
+ ind = snapops->create_indirect(inode, parent_ino, snap.index, del);
+ EXIT;
+ if(ind) {
+ iput(ind);
+ return 0;
+ }
+ else
+ return -EINVAL;
+}
+
+int snap_iterate(struct super_block *sb,
+ int (*repeat)(struct inode *inode, void *priv),
+ struct inode **start, void *priv, int flag)
+{
+ struct inode *inode = sb->s_root->d_inode;
+ struct snap_cache *cache;
+ struct snapshot_operations *snapops;
+
+ ENTRY;
+
+ cache = snap_find_cache(inode->i_dev);
+ if (!cache) {
+ EXIT;
+ return 0;
+ }
+ snapops = filter_c2csnapops(cache->cache_filter);
+ if (!snapops || !snapops->iterate) {
+ EXIT;
+ return 0;
+ }
+
+ EXIT;
+ return snapops->iterate(sb, repeat, start, priv, flag);
+}
+
+int snap_destroy_indirect(struct inode *pri, int index, struct inode *next_ind )
+{
+ struct snap_cache *cache;
+ struct snapshot_operations *snapops;
+
+ ENTRY;
+ cache = snap_find_cache(pri->i_dev);
+ if (!cache) {
+ EXIT;
+ return 0;
+ }
+ snapops = filter_c2csnapops(cache->cache_filter);
+ if (!snapops || !snapops->destroy_indirect) {
+ EXIT;
+ return 0;
+ }
+
+ EXIT;
+ return snapops->destroy_indirect(pri, index, next_ind);
+}
+
+int snap_restore_indirect(struct inode *pri, int index )
+{
+ struct snap_cache *cache;
+ struct snapshot_operations *snapops;
+
+ ENTRY;
+
+ cache = snap_find_cache(pri->i_dev);
+ if (!cache) {
+ EXIT;
+ return 0;
+ }
+ snapops = filter_c2csnapops(cache->cache_filter);
+ if (!snapops || !snapops->restore_indirect) {
+ EXIT;
+ return 0;
+ }
+
+ EXIT;
+ return snapops->restore_indirect(pri, index);
+}
+
+struct inode *snap_get_indirect(struct inode *pri, int *table, int slot)
+{
+ struct snap_cache *cache;
+ struct snapshot_operations *snapops;
+
+ ENTRY;
+
+ cache = snap_find_cache(pri->i_dev);
+ if (!cache) {
+ EXIT;
+ return NULL;
+ }
+ snapops = filter_c2csnapops(cache->cache_filter);
+ if (!snapops || !snapops->get_indirect) {
+ EXIT;
+ return NULL;
+ }
+
+ EXIT;
+ return snapops->get_indirect(pri, table, slot);
+}
+
+int snap_migrate_data(struct inode *dst, struct inode *src)
+{
+ struct snap_cache *cache;
+ struct snapshot_operations *snapops;
+
+ ENTRY;
+
+ cache = snap_find_cache(src->i_dev);
+ if (!cache) {
+ EXIT;
+ return 0;
+ }
+ snapops = filter_c2csnapops(cache->cache_filter);
+ if (!snapops || !snapops->migrate_data) {
+ EXIT;
+ return 0;
+ }
+
+ EXIT;
+ return snapops->migrate_data(dst, src);
+}
+
+int snap_set_indirect(struct inode *pri, ino_t ind_ino, int index, ino_t parent_ino)
+{
+ struct snap_cache *cache;
+ struct snapshot_operations *snapops;
+
+ ENTRY;
+
+ cache = snap_find_cache(pri->i_dev);
+ if (!cache) {
+ EXIT;
+ return -EINVAL;
+ }
+ snapops = filter_c2csnapops(cache->cache_filter);
+ if (!snapops || !snapops->set_indirect) {
+ EXIT;
+ return -EINVAL;
+ }
+
+ EXIT;
+ return snapops->set_indirect(pri, ind_ino, index, parent_ino);
+}
+
+
diff --git a/lustre/snapfs/snaptable.c b/lustre/snapfs/snaptable.c
new file mode 100644
index 0000000000..058164b349
--- /dev/null
+++ b/lustre/snapfs/snaptable.c
@@ -0,0 +1,1099 @@
+
+/*
+ * snaptable.c
+ *
+ * Manipulate snapshot tables
+ *
+ */
+
+#include <linux/sched.h>
+#include <linux/fs.h>
+#include <linux/malloc.h>
+#include <linux/locks.h>
+#include <linux/errno.h>
+#include <linux/swap.h>
+#include <linux/smp_lock.h>
+#include <linux/vmalloc.h>
+#include <linux/blkdev.h>
+#include <linux/sysrq.h>
+#include <linux/file.h>
+#include <linux/init.h>
+#include <linux/quotaops.h>
+
+#include <asm/uaccess.h>
+#include <asm/io.h>
+#include <asm/bitops.h>
+#include <asm/mmu_context.h>
+
+#include <linux/filter.h>
+#include <linux/snapsupport.h>
+#include <linux/snapfs.h>
+
+struct snap_table snap_tables[SNAP_MAX_TABLES];
+
+#if 0
+static void snap_lock_table(int table_no)
+{
+
+ spin_lock(snap_tables[table_no].tbl_lock);
+
+}
+
+static void snap_unlock_table(int table_no)
+{
+
+ spin_unlock(snap_tables[table_no].tbl_lock);
+
+}
+#endif
+
+int snap_index2slot(struct snap_table *snap_table, int snap_index)
+{
+ int slot;
+
+ for ( slot=0 ; slot<snap_table->tbl_count ; slot++ )
+ if ( snap_table->tbl_index[slot] == snap_index )
+ return slot;
+ return -1;
+}
+
+
+
+/* latest snap: returns
+ - the index of the latest snapshot before NOW
+ - hence it returns 0 in case all the volume snapshots lie in the future
+ - this is the index where a COW will land (will be created)
+ */
+void snap_last(struct snap_cache *info, struct snap *snap)
+{
+ int i ;
+ time_t now = CURRENT_TIME;
+ struct snap_table *table;
+ int tableno = info->cache_snap_tableno;
+
+ ENTRY;
+ if ( tableno < 0 || tableno > SNAP_MAX_TABLES ) {
+ printk(__FUNCTION__ ": invalid table no %d\n", tableno);
+ snap->index = -1;
+ }
+ table = &snap_tables[tableno];
+
+ /* start at the highest index in the superblock
+ snaptime array */
+ i = table->tbl_count - 1;
+
+ /* NOTE: i>0 is an unnecessary check */
+ while ( table->tbl_times[i] > now && i > 0) {
+ CDEBUG(D_SNAP, "time: %ld, i: %d\n", table->tbl_times[i], i);
+ i--;
+ }
+
+ snap->index = table->tbl_index[i];
+ snap->time = table->tbl_times[i];
+ CDEBUG(D_SNAP, "index: %d, time[i]: %ld, now: %ld\n",
+ snap->index, snap->time, now);
+ EXIT;
+ return;
+}
+
+/* return -1 if no COW is needed, otherwise the index of the
+ clone to COW to is returned
+*/
+
+int snap_needs_cow(struct inode *inode)
+{
+ struct snap snap;
+ struct snap_cache *cache;
+ int index = -1;
+ ENTRY;
+
+ cache = snap_find_cache(inode->i_dev);
+ if ( !cache ) {
+ EXIT;
+ return -1;
+ }
+
+ /* here we find the time of the last snap to compare with */
+ snap_last(cache, &snap);
+
+ /* decision .... if the snapshot is more recent than the object,
+ * then any change to the object should cause a COW.
+ */
+ if (inode->i_mtime <= snap.time && inode->i_ctime <= snap.time) {
+ index = snap.index;
+ }
+ printk("snap_needs_cow, ino %lu , get index %d\n",inode->i_ino, index);
+
+ EXIT;
+ return index;
+} /* snap_needs_cow */
+
+#if 0
+int snap_obd2snap(struct snap_clone_info *info, struct snap *snap)
+{
+ struct snap_table *table;
+ int tableno = info->clone_cache->cache_snap_tableno;
+ int index = info->clone_index;
+ int slot;
+
+ ENTRY;
+ if ( tableno < 0 || tableno > SNAP_MAX_TABLES ) {
+ printk(__FUNCTION__ ": invalid table no %d\n", tableno);
+ snap->index = -1;
+ }
+ table = &snap_tables[tableno];
+ slot = snap_index2slot(table, index);
+
+ snap->index = index;
+ snap->time = table->tbl_times[slot];
+ EXIT;
+ return slot;
+}
+#endif
+
+/* at what index is the current snapshot located */
+int snap_current(struct snap_cache *cache)
+{
+ int tableno = cache->cache_snap_tableno;
+
+ return snap_tables[tableno].tbl_index[0];
+}
+
+int snap_is_used(int table_no, int snap_index)
+
+{
+ /* ENTRY; */
+ if ( snap_index < 0 || snap_index >= SNAP_MAX ) {
+ printk(__FUNCTION__ ": invalid snapno %d,table %d\n",
+ snap_index, table_no);
+ EXIT;
+ return -1;
+ }
+ if ( table_no < 0 || table_no > SNAP_MAX_TABLES ) {
+ printk(__FUNCTION__ ": invalid snapno %d,table %d\n",
+ snap_index, table_no);
+ EXIT;
+ return -1;
+ }
+
+ /* EXIT; */
+ return snap_tables[table_no].tbl_used & (1<<snap_index);
+}
+
+void snap_use(int table_no, int snap_index)
+{
+ if ( snap_index < 0 || snap_index >= SNAP_MAX ) {
+ printk(__FUNCTION__ ": invalid snapno %d,table %d\n",
+ snap_index, table_no);
+ return;
+ }
+ if ( table_no < 0 || table_no > SNAP_MAX_TABLES ) {
+ printk(__FUNCTION__ ": invalid snapno %d,table %d\n",
+ snap_index, table_no);
+ return;
+ }
+ if ( snap_index2slot(&snap_tables[table_no], snap_index) < 0 )
+ return;
+
+ snap_tables[table_no].tbl_used |= (1<<snap_index);
+}
+
+void snap_unuse(int table_no, int snap_index)
+{
+ if ( snap_index < 0 || snap_index >= SNAP_MAX ) {
+ printk(__FUNCTION__ ": invalid snapno %d,table %d\n",
+ snap_index, table_no);
+ return;
+ }
+ if ( table_no < 0 || table_no > SNAP_MAX_TABLES ) {
+ printk(__FUNCTION__ ": invalid snapno %d,table %d\n",
+ snap_index, table_no);
+ return;
+ }
+ if ( snap_index2slot(&snap_tables[table_no], snap_index) < 0 )
+ return;
+
+ snap_tables[table_no].tbl_used &= ~(1<<snap_index);
+}
+
+static int nprint_buf(char *buf, int buflen, char *fmt, ...)
+{
+ va_list args;
+ int n;
+ char local_buf[1024];
+
+ va_start(args, fmt);
+ n = vsprintf(local_buf, fmt, args);
+ va_end(args);
+
+ if( n > buflen ) {
+ if( buflen > 1024) buflen=1024;
+ memcpy(buf, local_buf, buflen);
+ return buflen;
+ }
+ else {
+ memcpy(buf, local_buf, n);
+ return n;
+ }
+}
+
+int snap_print_table(struct snap_table_data *data, char *buf, int *buflen)
+{
+ int tableno = data->tblcmd_no;
+ int i;
+ struct snap_table *table;
+ char *buf_ptr;
+ int nleft = (*buflen);
+ int nprint = 0;
+
+ if ( tableno < 0 || tableno > SNAP_MAX_TABLES ) {
+ printk(__FUNCTION__ ": invalid table number %d\n", tableno);
+ EXIT;
+ return -EINVAL;
+ }
+
+ table = &snap_tables[tableno];
+
+ printk("------- snap table %d\n", tableno);
+ printk(" -- snap count %d\n", table->tbl_count);
+ printk(" -- snap used 0x%x\n", table->tbl_used);
+ for ( i = 0 ; i < SNAP_MAX ; i++ ) {
+ printk(" -- slot %d, idx %d, time %ld, name %s\n",
+ i, table->tbl_index[i], table->tbl_times[i],
+ table->tbl_name[i]);
+ }
+
+ buf_ptr = buf;
+ nprint= nprint_buf(buf_ptr, nleft, "------- snap table %d\n", tableno);
+ nleft -= nprint;
+ if( nleft > 0 ) buf_ptr += nprint;
+ else goto exit;
+ nprint = nprint_buf(buf_ptr, nleft, " -- snap count %d\n", table->tbl_count);
+ nleft -= nprint;
+ if( nleft > 0 ) buf_ptr += nprint;
+ else goto exit;
+ nprint = nprint_buf(buf_ptr, nleft, " -- snap used 0x%x\n", table->tbl_used);
+ nleft -= nprint;
+ if( nleft > 0 ) buf_ptr += nprint;
+ else goto exit;
+ for ( i = 0 ; i < SNAP_MAX ; i++ ) {
+ nprint = nprint_buf( buf_ptr, nleft,
+ " -- slot %d, idx %d, time %ld, name %s\n",
+ i, table->tbl_index[i], table->tbl_times[i],
+ table->tbl_name[i]);
+ nleft -= nprint;
+ if( nleft > 0 ) buf_ptr += nprint;
+ else goto exit;
+ }
+
+exit:
+ if(nleft > 0) (*buflen) = (*buflen) - nleft;
+
+ return 0;
+}
+
+int snap_install_table(int len, struct snap_table_data *data)
+{
+ int i, j;
+ int tableno = data->tblcmd_no;
+// int found_current;
+ struct snap_table *table;
+
+ if ( tableno < 0 || tableno > SNAP_MAX_TABLES ) {
+ printk(__FUNCTION__ ": invalid table number %d\n", tableno);
+ EXIT;
+ return -EINVAL;
+ }
+ table = &snap_tables[tableno];
+
+ /* for each index that is used by the current table
+ we need to make sure that the new table we are about
+ to put in contains that index too
+ */
+ for ( i = 0; i < SNAP_MAX ; i++ ) {
+ int foundit;
+ int err;
+
+ if ((err = snap_is_used(tableno, i)) < 0 ) {
+ printk(__FUNCTION__ ": table %d not used\n", tableno);
+ EXIT;
+ return -EINVAL;
+ } else if (err == 0) {
+ continue;
+ }
+
+ foundit = 0;
+ for (j = 0 ; j<= data->tblcmd_count ; j++) {
+ if ( i == data->tblcmd_snaps[j].index ) {
+ foundit = 1;
+ break;
+ }
+ }
+ if ( !foundit ) {
+ printk(__FUNCTION__ ": index %d not in table %d\n",
+ i, tableno);
+ return -EINVAL;
+ }
+ }
+
+ /* we must have:
+ - valid indices
+ - a current snapshot in the table
+ - increasing snapshot times
+ */
+// found_current = 0;
+ CDEBUG(D_SNAP, "snaplist: tblcmd_count %d\n", data->tblcmd_count);
+ for (i = 0 ; i < data->tblcmd_count ; i++) {
+
+ if ( (data->tblcmd_snaps[i].index < 0) ||
+ (data->tblcmd_snaps[i].index >= SNAP_MAX) ) {
+ printk(__FUNCTION__ ": snap_index out of range!\n");
+ return -EINVAL;
+ }
+
+ if (i>0 && data->tblcmd_snaps[i].time <=
+ data->tblcmd_snaps[i-1].time) {
+ printk(__FUNCTION__ ": times not increasing\n");
+ return -EINVAL;
+ }
+
+// if ( 0 == data->tblcmd_snaps[i].time ) {
+// found_current = 1;
+// break;
+// }
+ }
+// if ( !found_current ) {
+// printk(__FUNCTION__ "no current snapshot in table\n");
+// return -EINVAL;
+// }
+
+ /* ready to go: over write the table */
+/*
+ for (i = 0 ; i < data->tblcmd_count ; i++) {
+
+ table->tbl_times[i] = data->tblcmd_snaps[i].time;
+ table->tbl_index[i] = data->tblcmd_snaps[i].index;
+ memcpy(table->tbl_name[i], data->tblcmd_snaps[i].name,
+ SNAP_MAX_NAMELEN);
+ table->tbl_name[i][SNAP_MAX_NAMELEN - 1] = '\0';
+
+ CDEBUG(D_SNAP, "snaplist: i %d, time %ld, idx %d, name %s\n",
+ i, table->tbl_times[i], table->tbl_index[i],
+ table->tbl_name[i]);
+ }
+*/
+ /* below : new, we don't need current snapshot for data
+ * current snapshot always has slot 0, index 0, name "current"
+ */
+ table->tbl_times[0] = 0;
+ table->tbl_index[0] = 0;
+ strcpy(table->tbl_name[0], "current");
+
+ i=0;
+ CDEBUG(D_SNAP, "snaplist: i %d, time %ld, idx %d, name %s\n",
+ i, table->tbl_times[i], table->tbl_index[i],
+ table->tbl_name[i]);
+
+ for (i = 0 ; i < data->tblcmd_count ; i++) {
+
+ table->tbl_times[i+1] = data->tblcmd_snaps[i].time;
+ table->tbl_index[i+1] = data->tblcmd_snaps[i].index;
+ memcpy(table->tbl_name[i+1], data->tblcmd_snaps[i].name,
+ SNAP_MAX_NAMELEN);
+ table->tbl_name[i+1][SNAP_MAX_NAMELEN - 1] = '\0';
+
+ CDEBUG(D_SNAP, "snaplist: i %d, time %ld, idx %d, name %s\n",
+ i+1, table->tbl_times[i+1], table->tbl_index[i+1],
+ table->tbl_name[i+1]);
+ }
+
+ for ( i = data->tblcmd_count + 1 ; i < SNAP_MAX ; i++ ) {
+ table->tbl_times[i] = 0;
+ table->tbl_index[i] = 0;
+ memset(table->tbl_name[i], 0, SNAP_MAX_NAMELEN);
+ }
+
+ /* set the table count */
+// table->tbl_count = data->tblcmd_count;
+ table->tbl_count = data->tblcmd_count + 1;
+ return 0;
+}
+
+
+int snap_table_attach(int tableno, int snap_index)
+{
+ struct snap_table *table;
+
+ if ( tableno < 0 || tableno > SNAP_MAX_TABLES ) {
+ printk(__FUNCTION__ ": invalid table number %d\n", tableno);
+ EXIT;
+ return -EINVAL;
+ }
+ table = &snap_tables[tableno];
+
+ if ( snap_index2slot(table, snap_index) < 0 ) {
+ printk(__FUNCTION__ ": snap index %d not present in table %d\n",
+ snap_index, tableno);
+ return -EINVAL;
+ }
+
+ snap_use(tableno, snap_index);
+ return 0;
+}
+
+static int getdata(int len, void **data)
+{
+ void *tmp = NULL;
+
+ if (!len) {
+ *data = NULL;
+ return 0;
+ }
+
+ SNAP_ALLOC(tmp, void *, len);
+ if ( !tmp )
+ return -ENOMEM;
+
+ CDEBUG(D_MALLOC, "snap_alloc:len %d, add %p\n", len, tmp);
+
+ memset(tmp, 0, len);
+ if ( copy_from_user(tmp, *data, len)) {
+ SNAP_FREE(tmp, len);
+ CDEBUG(D_MALLOC, "snap_free:len %d, add %p\n", len, tmp);
+ return -EFAULT;
+ }
+ *data = tmp;
+
+ return 0;
+}
+
+static void freedata(void *data, int len) {
+ SNAP_FREE(data, len);
+ CDEBUG(D_MALLOC, "snap_free:len %d, add %p\n", len, data);
+}
+
+static int get_next_inode(struct inode *pri, void *ino)
+{
+ static ino_t prev_ino = -1 ;
+ ino_t this_ino = pri->i_ino;
+ ino_t find_ino = *(ino_t *)ino;
+ ino_t *found = ino;
+
+ if( find_ino == 0) {
+ (*found) = this_ino;
+ return -1;
+ }
+
+ if( find_ino == prev_ino ) {
+ (*found) = this_ino;
+ return -1;
+ }
+ else {
+ prev_ino = this_ino;
+ }
+ return 0;
+}
+
+
+static int snap_get_next_inode(struct snap_ino_list_data *data, ino_t *found_ino, ino_t *parent_ino)
+{
+ kdev_t dev = data->dev;
+ ino_t this_ino = data->ino;
+
+ struct snap_cache *cache;
+
+ struct inode *inode;
+ struct dentry * dentry;
+
+ ENTRY;
+
+ cache = snap_find_cache(dev);
+ if ( !cache ) {
+ EXIT;
+ return -EINVAL;
+ }
+
+ snap_iterate( cache->cache_sb, &get_next_inode, NULL, &(data->ino),
+ SNAP_ITERATE_COWED_INODE);
+
+ if( data->ino == this_ino ) {
+ data->ino = 0;
+ }
+
+ *found_ino = data->ino;
+
+ if( !(*found_ino) ) return 0;
+
+ *parent_ino = 0;
+ inode = iget (cache->cache_sb, *found_ino);
+ if (list_empty(&inode->i_dentry)) {
+ printk("No dentry for ino %lu, Error(XXX)! \n", inode->i_ino);
+ iput(inode);
+ return 0;
+ }
+ else {
+ dentry = dget(list_entry(inode->i_dentry.next, struct dentry, d_alias));
+ }
+ if( dentry->d_parent->d_inode)
+ *parent_ino = dentry->d_parent->d_inode->i_ino;
+ else
+ *parent_ino = 0;
+
+ dput(dentry);
+ iput(inode);
+
+ return 0;
+}
+/*
+static int snap_get_inode_info(struct snap_ino_list_data *data, int index)
+{
+ kdev_t dev = data->dev;
+ ino_t pri = data->ino;
+ int index = data->index;
+
+ struct snap_cache *cache;
+
+ struct inode *pri;
+ struct inode *ind;
+ ino_t ind_ino = 0;
+
+ ENTRY;
+
+ cache = snap_find_cache(dev);
+ if ( !cache ) {
+ EXIT;
+ return -EINVAL;
+ }
+ pri = iget(cache->cache->sb, pri_ino);
+ ind = snap_get_indirect(pri, NULL, index);
+ if(ind) {
+ ind_ino = ind->i_ino;
+ iput(ind);
+ }
+ return ind_ino;
+}
+*/
+
+static int print_inode(struct inode *pri,void *param)
+{
+ CDEBUG(D_SNAP, "cowed inode list: ino %lu \n", pri->i_ino);
+ return 0;
+}
+
+static int snap_print(struct super_block *sb, void *data)
+{
+ snap_iterate(sb, &print_inode, NULL, data, SNAP_ITERATE_COWED_INODE);
+ return 0;
+}
+
+static int delete_inode(struct inode *primary, void *param)
+{
+ struct snap_iterdata * data;
+ int tableno = 0;
+ int index = 0;
+ int rc = 0;
+
+ struct inode *redirect;
+ ino_t old_ind = 0;
+ struct snap_table *table;
+ int slot;
+ int delete_slot;
+ int this_index;
+ struct inode *next_ind = NULL;
+ int my_table[SNAP_MAX];
+
+ if(!primary) return 0;
+
+ data = (struct snap_iterdata*) param;
+
+ if(data) {
+ index = data->index;
+ tableno = data->tableno;
+ }
+
+ printk("delete_inode ino %lu, index %d\n", primary->i_ino, index);
+
+ table = &snap_tables[tableno];
+
+ redirect = snap_get_indirect(primary, NULL, index);
+
+ if(!redirect)
+ return 0;
+
+ old_ind = redirect->i_ino;
+ iput(redirect);
+ slot = snap_index2slot(table, index) - 1;
+ if( slot > 0 ) {
+ this_index = table->tbl_index[slot];
+ redirect = snap_get_indirect(primary, NULL, this_index);
+ if(redirect)
+ iput(redirect);
+ else {
+ snap_set_indirect(primary, old_ind, this_index, 0);
+ snap_set_indirect(primary, 0, index, 0);
+ return 0;
+ }
+ }
+
+ /* get the FIRST index after this and before NOW */
+ /* used for destroy_indirect and block level cow */
+ /* XXX fix this later, now use tbl_count, not NOW */
+ delete_slot = snap_index2slot(table, index);
+ for(slot = table->tbl_count; slot > delete_slot; slot --)
+ {
+ my_table[slot - delete_slot] = table->tbl_index[slot];
+ }
+ next_ind = snap_get_indirect
+ (primary, my_table, table->tbl_count - delete_slot );
+ if( next_ind && (next_ind->i_ino == primary->i_ino) ) {
+ iput(next_ind);
+ next_ind = NULL;
+ }
+
+ if( next_ind && (next_ind->i_ino == old_ind) ) {
+ iput(next_ind);
+ next_ind = NULL;
+ }
+
+ rc = snap_destroy_indirect(primary, index, next_ind);
+
+ if(next_ind) iput(next_ind);
+
+ if(rc != 0)
+ printk("ERROR:snap_destroy_indirect(ino %lu,index %d),ret %d\n", primary->i_ino, index, rc);
+ return 0;
+}
+
+static int snap_delete(struct super_block *sb, struct snap_iterdata *data)
+//static int snap_delete(struct super_block *sb, void *data)
+{
+ CDEBUG(D_SNAP, "dev %d, tableno %d, index %d, time %lu\n",
+ data->dev, data->tableno, data->index, data->time );
+
+ snap_iterate(sb,&delete_inode,NULL, data, SNAP_ITERATE_COWED_INODE);
+ return 0;
+}
+
+static int delete_new_inode(struct inode *pri, void *param)
+{
+ struct snap_iterdata * data;
+
+ int index = 1;
+ time_t restore_time = 0xFFFFFFFF;
+
+ ENTRY;
+
+ if(!pri) return 0;
+
+ if(snap_is_redirector(pri)){
+ EXIT;
+ return 0;
+ }
+
+ data = (struct snap_iterdata*) param;
+
+ if(data) {
+ index = data->index;
+ restore_time = data->time;
+ }
+
+ CDEBUG(D_SNAP, "ino %lu, index=%d, time=%lu\n",
+ pri->i_ino, index, restore_time);
+
+
+ if( pri->i_mtime > restore_time || pri->i_ctime > restore_time ) {
+ struct list_head *head = &pri->i_dentry, *pos;
+
+ CDEBUG(D_SNAP, "snap_restore ino %lu is newer, delete \n",pri->i_ino);
+ for( pos = head->next; pos != head; pos = pos->next ){
+// d_invalidate( list_entry(pos, struct dentry, d_alias) );
+ d_drop( list_entry(pos, struct dentry, d_alias) );
+ }
+ pri->i_nlink = 0;
+ }
+ return 0;
+
+}
+
+static int restore_inode(struct inode *pri, void *param)
+{
+ struct snap_iterdata * data;
+// struct snap_cache *cache;
+ int tableno = 0;
+
+ int index = 1;
+ time_t restore_time = 0xFFFFFFFF;
+
+ struct inode *ind = NULL;
+ int slot;
+ int restore_slot;
+ struct snap_table *table;
+// int my_table[SNAP_MAX];
+ int restore_index;
+
+ ENTRY;
+
+ if(!pri) return 0;
+
+ data = (struct snap_iterdata*) param;
+
+ if(data) {
+ index = data->index;
+ tableno = data->tableno;
+ restore_time = data->time;
+ }
+
+ CDEBUG(D_SNAP, "ino %lu, index=%d, time=%lu, tableno %d\n",
+ pri->i_ino, index, restore_time, tableno);
+
+ /* XXX: should we have = here? */
+ if( pri->i_mtime > restore_time || pri->i_ctime > restore_time )
+ {
+ restore_index = index;
+ table = &snap_tables[tableno];
+ /* first find if there are indirected at the index */
+ ind = snap_get_indirect(pri, NULL, index);
+ /* if not found, get the FIRST index after this and before NOW*/
+ /* XXX fix this later, now use tbl_count, not NOW */
+ if(!ind) {
+ restore_slot = snap_index2slot(table, index);
+ for(slot = restore_slot; slot <= table->tbl_count;
+ slot++) {
+ ind = snap_get_indirect (pri, NULL,
+ table->tbl_index[slot]);
+ if(ind) {
+ restore_index = table->tbl_index[slot];
+ break;
+ }
+ }
+/* for(slot = table->tbl_count; slot >= restore_slot;
+ slot --)
+ {
+ my_table[slot - restore_slot + 1] =
+ table->tbl_index[slot];
+ }
+ ind = snap_get_indirect (pri, my_table,
+ table->tbl_count - restore_slot + 1);
+
+ if( ind && (ind->i_ino == pri->i_ino) ) {
+ iput(ind);
+ ind = NULL;
+ }
+*/
+ }
+
+ if(ind) {
+ CDEBUG(D_SNAP, "restore ino %lu with index %d\n",
+ pri->i_ino, restore_index);
+ iput(ind);
+// snap_restore_indirect(pri, index);
+ snap_restore_indirect(pri, restore_index);
+ /* XXX */
+ //delete_inode(pri, param);
+ snap_destroy_indirect(pri, restore_index, NULL);
+ }
+ else {
+ CDEBUG(D_SNAP, "ERROR:restore ino %lu\n", pri->i_ino);
+ }
+ }
+ else {
+ printk("ino %lu is older, don't restore\n",pri->i_ino);
+ }
+ EXIT;
+ return 0;
+}
+
+//int snap_restore(struct super_block *sb, void *data)
+static int snap_restore(struct super_block *sb, struct snap_iterdata *data)
+{
+ CDEBUG(D_SNAP, "dev %d, tableno %d, index %d, time %lu\n",
+ data->dev, data->tableno, data->index, data->time );
+
+ snap_iterate(sb, &delete_new_inode, NULL, data, SNAP_ITERATE_ALL_INODE);
+ snap_iterate(sb, &restore_inode, NULL, data, SNAP_ITERATE_COWED_INODE );
+ return 0;
+}
+
+/* return the index number of a name in a table */
+int snap_get_index_from_name(int tableno, char *name)
+{
+ struct snap_table *table;
+ int slot;
+
+ if ( tableno < 0 || tableno > SNAP_MAX_TABLES ) {
+ printk(__FUNCTION__ ": invalid table number %d\n", tableno);
+ return -EINVAL;
+ }
+
+ table = &snap_tables[tableno];
+
+ for ( slot = 0 ; slot < SNAP_MAX ; slot++ ) {
+/* if(memcmp (table->tbl_name[slot], name,
+ strlen(table->tbl_name[slot]) ) == 0 ) {
+ return table->tbl_index[slot];
+ }
+*/
+ if(strncmp (table->tbl_name[slot], name,
+ SNAP_MAX_NAMELEN) == 0 ) {
+ return table->tbl_index[slot];
+ }
+ }
+ return -EINVAL;
+}
+
+int snap_iterate_func(int len, struct snap_ioc_data *ioc_data, unsigned int cmd)
+{
+ struct snap_iterdata data;
+
+ kdev_t dev ;
+ char name[SNAP_MAX_NAMELEN];
+
+ int index ;
+ int tableno;
+ int name_len;
+ int slot;
+
+ struct super_block *sb;
+ struct snap_cache *cache;
+ struct snap_table *table;
+
+ ENTRY;
+
+ dev = ioc_data->dev;
+ cache = snap_find_cache(dev);
+ if ( !cache ) {
+ EXIT;
+ return -EINVAL;
+ }
+
+ sb = cache->cache_sb;
+ tableno = cache->cache_snap_tableno;
+ table = &snap_tables[tableno];
+
+ name_len = len - sizeof(kdev_t);
+ memset(name, 0, SNAP_MAX_NAMELEN);
+ if(name_len > SNAP_MAX_NAMELEN)
+ name_len = SNAP_MAX_NAMELEN;
+ if(name_len < 0 )
+ name_len = 0;
+ memcpy(name, ioc_data->name, name_len);
+ if ( (index = snap_get_index_from_name (tableno, name)) < 0 ) {
+ EXIT;
+ return -EINVAL;
+ }
+
+ data.dev = dev;
+ data.index = index;
+ data.tableno = tableno;
+ slot = snap_index2slot (table, index);
+ if( slot < 0 ) {
+ EXIT;
+ return -EINVAL;
+ }
+ data.time = table->tbl_times[slot];
+
+ CDEBUG(D_SNAP, "dev %d, tableno %d, index %d, time %lu\n",
+ data.dev, data.tableno, data.index, data.time );
+
+ switch (cmd) {
+ case IOC_SNAP_DEBUG:
+ snap_print(sb, &data);
+ break;
+ case IOC_SNAP_DELETE:
+ snap_delete(sb, &data);
+ break;
+ case IOC_SNAP_RESTORE:
+ snap_restore(sb, &data);
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ EXIT;
+
+ return 0;
+}
+
+int snap_ioctl (struct inode * inode, struct file * filp,
+ unsigned int cmd, unsigned long arg)
+{
+ void *uarg, *karg;
+ int len;
+ int err;
+ kdev_t dev;
+ struct {
+ int len;
+ char *data;
+ }input;
+ int rc = 0;
+
+ ENTRY;
+
+ dev = MINOR(inode->i_rdev);
+ if (dev != SNAP_PSDEV_MINOR)
+ return -ENODEV;
+
+ if (!inode) {
+ CDEBUG(D_IOCTL, "invalid inode\n");
+ return -EINVAL;
+ }
+
+ if ( _IOC_TYPE(cmd) != IOC_SNAP_TYPE ||
+ _IOC_NR(cmd) < IOC_SNAP_MIN_NR ||
+ _IOC_NR(cmd) > IOC_SNAP_MAX_NR ) {
+ CDEBUG(D_IOCTL, "invalid ioctl ( type %d, nr %d, size %d )\n",
+ _IOC_TYPE(cmd), _IOC_NR(cmd), _IOC_SIZE(cmd));
+ EXIT;
+ return -EINVAL;
+ }
+
+ /* get data structures */
+ err = copy_from_user(&input, (void *)arg, sizeof(input));
+ if ( err ) {
+ EXIT;
+ return err;
+ }
+ uarg = input.data;
+ len = input.len;
+
+ karg = input.data;
+ err = getdata(input.len, &karg);
+ if ( err ) {
+ EXIT;
+ return err;
+ }
+
+ switch (cmd) {
+ case IOC_SNAP_SETTABLE:
+ rc = snap_install_table(len, karg);
+ break;
+ case IOC_SNAP_PRINTTABLE: {
+ struct output_data{
+ int len;
+ char buf[1024];
+ }output;
+ output.len = sizeof(output.buf);
+ snap_print_table(karg, output.buf, &(output.len));
+ rc = copy_to_user((char *)arg, &output, output.len+sizeof(int));
+ break;
+ }
+ case IOC_SNAP_GETINDEXFROMNAME: {
+ int index = 0;
+ char name[SNAP_MAX_NAMELEN];
+ int tableno = 0;
+ struct snap_cache *cache;
+ kdev_t dev;
+ int name_len;
+
+ struct get_index_struct {
+ kdev_t dev;
+ char name[SNAP_MAX_NAMELEN];
+ };
+
+ struct get_index_struct *data = karg;
+
+ name_len = len - sizeof(kdev_t);
+ dev = data->dev;
+ memset(name, 0, SNAP_MAX_NAMELEN);
+ if(name_len > SNAP_MAX_NAMELEN)
+ name_len = SNAP_MAX_NAMELEN;
+ if(name_len < 0 )
+ name_len = 0;
+ /*for(i=0 ; i< name_len; i++) {
+ name[i] = data->name[i];
+ }
+ */
+ memcpy(name, data->name, name_len);
+ printk("dev %d , len %d, name_len %d, find name is [%s]\n", dev, len, name_len, name);
+ cache = snap_find_cache(dev);
+ if ( !cache ) {
+ EXIT;
+ rc = -EINVAL;
+ break;
+ }
+ tableno = cache->cache_snap_tableno;
+
+ index = snap_get_index_from_name(tableno, name);
+ rc = copy_to_user((char *)arg, &index, sizeof(index));
+ break;
+ }
+ case IOC_SNAP_GET_NEXT_INO: {
+ struct get_ino_struct{
+ ino_t found_ino;
+ ino_t parent_ino;
+ }get_ino;
+ get_ino.found_ino = 0;
+ get_ino.parent_ino = 0;
+ rc = snap_get_next_inode(karg, &get_ino.found_ino, &get_ino.parent_ino);
+ rc = copy_to_user((char *)arg, &get_ino, sizeof(get_ino));
+ break;
+ }
+ case IOC_SNAP_GET_INO_INFO: {
+ struct ioc_ino_info{
+ kdev_t dev;
+ ino_t ino;
+ int index;
+ };
+ struct snap_cache *cache;
+ struct inode *pri;
+ struct inode *ind;
+ struct ioc_ino_info *data = karg;
+ ino_t ind_ino = 0;
+
+ cache = snap_find_cache(data->dev);
+ if ( !cache ) {
+ EXIT;
+ rc = -EINVAL;
+ break;
+ }
+ printk("get_ino_info, dev %d, ino %lu, index %d\n",
+ data->dev, data->ino, data->index);
+ pri = iget(cache->cache_sb, data->ino);
+ ind = snap_get_indirect(pri, NULL, data->index);
+ if(ind) {
+ ind_ino = ind->i_ino;
+ iput(ind);
+ }
+ iput(pri);
+ printk("get_ino_info, get ind %lu\n", ind_ino);
+ rc = copy_to_user((char *)arg, &ind_ino, sizeof(ino_t));
+ break;
+ }
+ case IOC_SNAP_DELETE:
+ case IOC_SNAP_RESTORE:
+ case IOC_SNAP_DEBUG:
+ rc = snap_iterate_func(len, karg, cmd);
+ break;
+ case IOC_SNAP_DEVFAIL:
+ snap_debug_failcode = (unsigned int)arg;
+ break;
+ case IOC_SNAP_SHOW_DOTSNAP: {
+ struct ioc_show_info{
+ kdev_t dev;
+ int show;
+ };
+ struct snap_cache *cache;
+ struct ioc_show_info *data = karg;
+
+ cache = snap_find_cache(data->dev);
+ if( !cache ) {
+ EXIT;
+ rc = -EINVAL;
+ break;
+ }
+ cache->cache_show_dotsnap = (char)data->show;
+ CDEBUG(D_IOCTL, "Set show dotsnap: %s\n",
+ data->show ? "Yes" : "No");
+
+ break;
+ }
+
+ default:
+ rc = -EINVAL;
+ break;
+ }
+
+ freedata(karg, input.len);
+ EXIT;
+ return rc;
+}
diff --git a/lustre/snapfs/super.c b/lustre/snapfs/super.c
new file mode 100644
index 0000000000..f1019771a8
--- /dev/null
+++ b/lustre/snapfs/super.c
@@ -0,0 +1,714 @@
+/*
+ * snap_current
+ *
+ * Copyright (C) 1998 Peter J. Braam
+ * Copyright (C) 2000 Stelias Computing, Inc.
+ * Copyright (C) 2000 Red Hat, Inc.
+ * Copyright (C) 2000 Mountain View Data, Inc.
+ *
+ * Author: Peter J. Braam <braam@mountainviewdata.com>
+ */
+
+
+#include <stdarg.h>
+
+#include <asm/bitops.h>
+#include <asm/uaccess.h>
+#include <asm/system.h>
+
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/dcache.h>
+
+#ifdef CONFIG_SNAPFS_EXT2
+#include <linux/ext2_fs.h>
+#endif
+#ifdef CONFIG_SNAPFS_EXT3
+#include <linux/ext3_fs.h>
+#endif
+
+#include <linux/malloc.h>
+#include <linux/vmalloc.h>
+#include <linux/sched.h>
+#include <linux/stat.h>
+#include <linux/string.h>
+#include <linux/locks.h>
+#include <linux/blkdev.h>
+#include <linux/init.h>
+#define __NO_VERSION__
+#include <linux/module.h>
+
+#include <linux/filter.h>
+#include <linux/snapfs.h>
+#include <linux/snapsupport.h>
+
+#ifdef SNAP_DEBUG
+long snap_vmemory = 0;
+long snap_kmemory = 0;
+unsigned int snap_debug_failcode = 0;
+#endif
+
+extern struct snap_cache *snap_init_cache(void);
+extern inline void snap_cache_add(struct snap_cache *, kdev_t);
+extern inline void snap_init_cache_hash(void);
+
+extern int snap_get_index_from_name (int tableno, char *name);
+
+#ifdef CONFIG_SNAPFS_EXT2
+extern struct snapshot_operations ext2_snap_operations;
+extern struct journal_ops snap_ext2_journal_ops;
+#endif
+
+#ifdef CONFIG_SNAPFS_EXT3
+extern struct snapshot_operations ext3_snap_operations;
+extern struct journal_ops snap_ext3_journal_ops;
+#endif
+
+/* returns an allocated string, copied out from data if opt is found */
+static char *read_opt(const char *opt, char *data)
+{
+ char *value;
+ char *retval;
+
+ CDEBUG(D_SUPER, "option: %s, data %s\n", opt, data);
+ if ( strncmp(opt, data, strlen(opt)) )
+ return NULL;
+
+ if ( (value = strchr(data, '=')) == NULL )
+ return NULL;
+
+ value++;
+ SNAP_ALLOC(retval, char *, strlen(value) + 1);
+ if ( !retval ) {
+ printk("snapfs: Out of memory!\n");
+ return NULL;
+ }
+
+ strcpy(retval, value);
+ CDEBUG(D_SUPER, "Assigned option: %s, value %s\n", opt, retval);
+ return retval;
+}
+
+static inline void store_opt(char **dst, char *opt)
+{
+ if (dst) {
+ if (*dst)
+ SNAP_FREE(*dst, strlen(*dst) + 1);
+ *dst = opt;
+ } else
+ SNAP_FREE(opt, strlen(opt) + 1);
+}
+
+/* Find the options for snapfs in "options", saving them into the
+ * passed pointers. If the pointer is null, the option is discarded.
+ * Copy out all non-snapfs options into cache_data (to be passed
+ * to the read_super operation of the cache). The return value will
+ * be a pointer to the end of the cache_data.
+ */
+static char *snapfs_options(char *options, char *cache_data,
+ char **cache_type, char **cow_type,
+ char **snaptable)
+{
+ char *this_char;
+ char *cache_data_end = cache_data;
+
+ /* set the defaults here */
+ if (cache_type && !*cache_type) {
+ SNAP_ALLOC(*cache_type, char *, strlen("ext2") + 1);
+ strcpy(*cache_type, "ext2");
+ }
+ if (cow_type && !*cow_type) {
+ SNAP_ALLOC(*cow_type, char *, strlen("block") + 1);
+ strcpy(*cow_type, "block");
+ }
+ if (snaptable && !*snaptable) {
+ SNAP_ALLOC(*snaptable, char *, strlen("-1")+1);
+ strcpy(*snaptable, "-1");
+ }
+
+ if (!options || !cache_data)
+ return cache_data_end;
+
+ CDEBUG(D_SUPER, "parsing options\n");
+ for (this_char = strtok (options, ",");
+ this_char != NULL;
+ this_char = strtok (NULL, ",")) {
+ char *opt;
+ CDEBUG(D_SUPER, "this_char %s\n", this_char);
+
+ if ( (opt = read_opt("cache_type", this_char)) ) {
+ store_opt(cache_type, opt);
+ continue;
+ }
+ if ( (opt = read_opt("cow_type", this_char)) ){
+ store_opt(cow_type, opt);
+ continue;
+ }
+ if ( (opt = read_opt("table", this_char)) ) {
+ store_opt(snaptable, opt);
+ continue;
+ }
+
+ cache_data_end += sprintf(cache_data_end, "%s%s",
+ cache_data_end != cache_data ? ",":"",
+ this_char);
+ }
+
+ return cache_data_end;
+}
+
+int snapfs_remount(struct super_block * sb, int *flags, char *data)
+{
+ char *cache_data = NULL;
+ char *snapno = NULL;
+ char *cache_data_end;
+ struct snap_cache *cache = NULL;
+ struct super_operations *sops;
+ int err = 0;
+
+ ENTRY;
+ CDEBUG(D_MALLOC, "before remount: kmem %ld, vmem %ld\n",
+ snap_kmemory, snap_vmemory);
+ CDEBUG(D_SUPER, "remount opts: %s\n", data ? (char *)data : "(none)");
+ if (data) {
+ /* reserve space for the cache's data */
+ SNAP_ALLOC(cache_data, void *, PAGE_SIZE);
+ if ( !cache_data ) {
+ err = -ENOMEM;
+ EXIT;
+ goto out_err;
+ }
+ }
+
+ cache = snap_find_cache(sb->s_dev);
+ if (!cache) {
+ printk(__FUNCTION__ ": cannot find cache on remount\n");
+ err = -ENODEV;
+ EXIT;
+ goto out_err;
+ }
+
+ /* If an option has not yet been set, we allow it to be set on
+ * remount. If an option already has a value, we pass NULL for
+ * the option pointer, which means that the snapfs option
+ * will be parsed but discarded.
+ */
+ cache_data_end = snapfs_options(data, cache_data, NULL, NULL, &snapno);
+
+ if (cache_data) {
+ if (cache_data_end == cache_data) {
+ SNAP_FREE(cache_data, PAGE_SIZE);
+ cache_data = NULL;
+ } else {
+ CDEBUG(D_SUPER, "cache_data at %p is: %s\n", cache_data,
+ cache_data);
+ }
+ }
+
+
+ sops = filter_c2csops(cache->cache_filter);
+ if (sops->remount_fs) {
+ err = sops->remount_fs(sb, flags, cache_data);
+ }
+
+ CDEBUG(D_MALLOC, "after remount: kmem %ld, vmem %ld\n",
+ snap_kmemory, snap_vmemory);
+ EXIT;
+out_err:
+ if (cache_data)
+ SNAP_FREE(cache_data, PAGE_SIZE);
+ return err;
+}
+
+/* XXXX remount: needed if snapfs was mounted RO at boot time
+ without a snaptable
+*/
+
+
+/*
+ * snapfs super block read.
+ *
+ * Allocate a struct snap_cache, determine the underlying fs type,
+ * read the underlying fs superblock, save the underlying fs ops,
+ * and then replace them with snapfs ops.
+ *
+ * Remove the snapfs options before passing to underlying fs.
+ */
+struct super_block *
+snapfs_read_super (
+ struct super_block *sb,
+ void *data,
+ int silent)
+{
+ struct file_system_type *fstype;
+ struct snap_cache *cache = NULL;
+ char *cache_data = NULL;
+ char *cache_data_end;
+ char *cache_type = NULL;
+ char *cow_type = NULL;
+ char *snapno = NULL;
+ char *endptr;
+ int tableno;
+
+ ENTRY;
+ CDEBUG(D_MALLOC, "before parsing: kmem %ld, vmem %ld\n",
+ snap_kmemory, snap_vmemory);
+
+ /* reserve space for the cache's data */
+ SNAP_ALLOC(cache_data, void *, PAGE_SIZE);
+ if ( !cache_data ) {
+ printk("snapfs_read_super: Cannot allocate data page.\n");
+ EXIT;
+ goto out_err;
+ }
+
+ CDEBUG(D_SUPER, "mount opts: %s\n", data ? (char *)data : "(none)");
+
+ /* read and validate options */
+ cache_data_end = snapfs_options(data, cache_data, &cache_type, &cow_type, &snapno);
+
+ /* Need to free cache_type and snapno when it's not in use */
+
+ /* was there anything for the cache filesystem in the data? */
+ if (cache_data_end == cache_data) {
+ SNAP_FREE(cache_data, PAGE_SIZE);
+ cache_data = NULL;
+ } else {
+ CDEBUG(D_SUPER, "cache_data at %p is: %s\n", cache_data,
+ cache_data);
+ }
+
+ /* set up the cache */
+ cache = snap_init_cache();
+ if ( !cache ) {
+ printk("snapfs_read_super: failure allocating cache.\n");
+ EXIT;
+ goto out_err;
+ }
+
+ fstype = get_fs_type(cache_type);
+ if ( !fstype || !fstype->read_super) {
+ EXIT;
+ goto out_err;
+ }
+
+ cache->cache_filter = filter_get_filter_fs((const char *)cache_type);
+ /* XXX if cache->cache_filter==NULL?although it's rare ***/
+
+
+ /*
+ * Read the underlying file system superblock - ext2, ext3, reiser.
+ * This performs the underlying mount operation. The snapfs options
+ * have been removed from 'cache_data'.
+ *
+ * Note: It's assumed that sb is always returned.
+ */
+ CDEBUG(D_SUPER, "\n");
+ if (fstype->read_super(sb, cache_data, silent) != sb) {
+ printk("snapfs: cache mount failure.\n");
+ EXIT;
+ goto out_err;
+ }
+
+ /* XXX now look at the flags in the superblock and determine if this
+ is a block cow file system or a file cow fs. Then assign the
+ snap operations accordingly. This goes in the sections for ext2/ext3/xfs etc
+ */
+
+ /* this might have been freed above */
+ CDEBUG(D_SUPER, "\n");
+ if (cache_data) {
+ SNAP_FREE(cache_data, PAGE_SIZE);
+ cache_data = NULL;
+ }
+
+
+ /*
+ * We now know the dev of the cache: hash the cache.
+ *
+ * 'cache' is the struct snap_cache allocated for this
+ * snapfs mount.
+ */
+ CDEBUG(D_SUPER, "\n");
+ snap_cache_add(cache, sb->s_dev);
+
+ tableno = simple_strtoul(snapno, &endptr, 0);
+ cache->cache_snap_tableno = tableno;
+
+ CDEBUG(D_SUPER, "get tableno %d\n", cache->cache_snap_tableno);
+
+ /*
+ * make sure we have our own super operations
+ *
+ * Initialize or re-initialize the cache->cache_ops shared
+ * struct snap_ops structure set based on the underlying
+ * file system type.
+ */
+ CDEBUG(D_SUPER, "\n");
+ filter_setup_super_ops(cache->cache_filter, sb->s_op,
+ ¤tfs_super_ops);
+ CDEBUG(D_SUPER, "\n");
+ sb->s_op = filter_c2usops(cache->cache_filter);
+ /*
+ * Save pointers in the snap_cache structure to the
+ * snapfs and underlying file system superblocks.
+ */
+ cache->cache_sb = sb; /* Underlying file system superblock. */
+
+ /* set up snapshot ops, handle COMPAT_FEATUREs */
+ if( 0 ){
+ }
+#ifdef CONFIG_SNAPFS_EXT2
+ else if ( strcmp (cache_type,"ext2") == 0 ){
+ cache->cache_type = FILTER_FS_EXT2;
+ filter_setup_snapshot_ops(cache->cache_filter,
+ &ext2_snap_operations);
+ filter_setup_journal_ops(cache->cache_filter,
+ &snap_ext2_journal_ops);
+ if( !EXT2_HAS_COMPAT_FEATURE(sb, EXT2_FEATURE_COMPAT_SNAPFS) ){
+ if( strcmp(cow_type, "block")==0 ){
+ sb->u.ext2_sb.s_feature_compat |=
+ EXT2_FEATURE_COMPAT_BLOCKCOW;
+ sb->u.ext2_sb.s_es->s_feature_compat |=
+ cpu_to_le32(EXT2_FEATURE_COMPAT_BLOCKCOW);
+ }
+ }
+ sb->u.ext2_sb.s_last_cowed_ino = 0;
+ }
+#endif
+#ifdef CONFIG_SNAPFS_EXT3
+ else if ( strcmp (cache_type,"ext3") == 0 ){
+ cache->cache_type = FILTER_FS_EXT3;
+ filter_setup_snapshot_ops(cache->cache_filter,
+ &ext3_snap_operations);
+ filter_setup_journal_ops(cache->cache_filter,
+ &snap_ext3_journal_ops);
+ if( !EXT3_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_SNAPFS) ){
+ if( strcmp(cow_type, "block")==0 ){
+ sb->u.ext3_sb.s_es->s_feature_compat |=
+ cpu_to_le32(EXT3_FEATURE_COMPAT_BLOCKCOW);
+ }
+ }
+ sb->u.ext3_sb.s_last_cowed_ino = 0;
+ }
+#endif
+
+ CDEBUG(D_SUPER, "\n");
+ /* now get our own directory operations */
+ if ( sb->s_root && sb->s_root->d_inode ) {
+ CDEBUG(D_SUPER, "\n");
+ filter_setup_dir_ops(cache->cache_filter,
+ sb->s_root->d_inode->i_op,
+ ¤tfs_dir_iops);
+ CDEBUG(D_SUPER, "\n");
+ sb->s_root->d_inode->i_op =filter_c2udiops(cache->cache_filter);
+// CDEBUG(D_SUPER, "\n");
+// sb->s_root->d_inode->i_snapop = ext2_snapops();
+
+ CDEBUG(D_SUPER, "lookup at %p\n",
+ sb->s_root->d_inode->i_op->lookup);
+#if 0
+ /* XXX is this needed ?? */
+ filter_setup_dentry_ops(cache->cache_filter,
+ sb->s_root->d_op,
+ ¤tfs_dentry_ops);
+ sb->s_root->d_op = filter_c2udops(cache->cache_filter);
+#endif
+ }
+ /*
+ * Save a pointer to the snap_cache structure in the
+ * "snap_current" superblock.
+ */
+ (struct snap_cache *) sb->u.generic_sbp = cache;
+ CDEBUG(D_SUPER, "sb %lx, sb->u.generic_sbp: %lx\n",
+ (ulong) sb, (ulong) sb->u.generic_sbp);
+
+ /* we can free snapno and cache_type now, because it's not used */
+ if (snapno) {
+ SNAP_FREE(snapno, strlen(snapno) + 1);
+ snapno = NULL;
+ }
+ if (cache_type) {
+ SNAP_FREE(cache_type, strlen(cache_type) + 1);
+ snapno = NULL;
+ }
+ if (cow_type) {
+ SNAP_FREE(cow_type, strlen(cow_type) + 1);
+ cow_type = NULL;
+ }
+
+ CDEBUG(D_MALLOC, "after mounting: kmem %ld, vmem %ld\n",
+ snap_kmemory, snap_vmemory);
+
+ MOD_INC_USE_COUNT;
+ EXIT;
+ return sb;
+
+ out_err:
+ CDEBUG(D_SUPER, "out_err called\n");
+ if (cache)
+ SNAP_FREE(cache, sizeof(struct snap_cache));
+ if (cache_data)
+ SNAP_FREE(cache_data, PAGE_SIZE);
+ if (snapno)
+ SNAP_FREE(snapno, strlen(snapno) + 1);
+ if (cache_type)
+ SNAP_FREE(cache_type, strlen(cache_type) + 1);
+ if (cow_type)
+ SNAP_FREE(cow_type, strlen(cow_type) + 1);
+
+ CDEBUG(D_MALLOC, "mount error exit: kmem %ld, vmem %ld\n",
+ snap_kmemory, snap_vmemory);
+ return NULL;
+}
+
+
+struct file_system_type snapfs_current_type = {
+ "snap_current",
+ FS_REQUIRES_DEV, /* can use Ibaskets when ext2 does */
+ snapfs_read_super,
+ NULL
+};
+
+
+/* Find the options for the clone. These consist of a cache device
+ and an index in the snaptable associated with that device.
+*/
+static char *clonefs_options(char *options, char *cache_data,
+ char **devstr, char **namestr)
+{
+ char *this_char;
+ char *cache_data_end = cache_data;
+
+ if (!options || !cache_data)
+ return cache_data_end;
+
+ CDEBUG(D_SUPER, "parsing options\n");
+ for (this_char = strtok (options, ",");
+ this_char != NULL;
+ this_char = strtok (NULL, ",")) {
+ char *opt;
+ CDEBUG(D_SUPER, "this_char %s\n", this_char);
+
+ if ( (opt = read_opt("dev", this_char)) ) {
+ store_opt(devstr, opt);
+ continue;
+ }
+ if ( (opt = read_opt("name", this_char)) ) {
+ store_opt(namestr, opt);
+ continue;
+ }
+
+ cache_data_end += sprintf(cache_data_end, "%s%s",
+ cache_data_end != cache_data ? ",":"",
+ this_char);
+ }
+
+ return cache_data_end;
+}
+
+static int snapfs_path2dev(char *dev_path, kdev_t *dev)
+{
+ struct dentry *dentry;
+
+ dentry = lookup_dentry(dev_path, NULL, 0);
+ if (IS_ERR(dentry))
+ return PTR_ERR(dentry);
+
+ if (!dentry->d_inode)
+ return -ENODEV;
+
+ if (!S_ISBLK(dentry->d_inode->i_mode))
+ return -ENODEV;
+
+ *dev = dentry->d_inode->i_rdev;
+
+ return 0;
+}
+
+
+extern struct super_operations clone_super_ops;
+
+/*
+ * We always need to remove the snapfs options before passing
+ * to bottom FS.
+ */
+struct super_block *
+clone_read_super(
+ struct super_block *sb,
+ void *data,
+ int silent)
+{
+ struct snap_clone_info *clone_sb;
+ struct snap_cache *snap_cache = NULL;
+ int err;
+ char *cache_data = NULL;
+ char *cache_data_end;
+ char *devstr = NULL;
+ kdev_t dev;
+ char *namestr = NULL;
+ //char *endptr;
+ int index;
+ ino_t root_ino;
+ struct inode *root_inode;
+
+ ENTRY;
+
+ CDEBUG(D_MALLOC, "before parsing: kmem %ld, vmem %ld\n",
+ snap_kmemory, snap_vmemory);
+
+ /* reserve space for the cache's data */
+ SNAP_ALLOC(cache_data, void *, PAGE_SIZE);
+ if ( !cache_data ) {
+ printk("clone_read_super: Cannot allocate data page.\n");
+ EXIT;
+ goto out_err;
+ }
+
+ CDEBUG(D_SUPER, "mount opts: %s\n", data ? (char *)data : "(none)");
+
+ /* read and validate options */
+ cache_data_end = clonefs_options(data, cache_data, &devstr, &namestr);
+
+ /* was there anything for the cache filesystem in the data? */
+ if (cache_data_end == cache_data) {
+ SNAP_FREE(cache_data, PAGE_SIZE);
+ cache_data = NULL;
+ } else {
+ printk("clonefs: invalid mount option %s\n", cache_data);
+ EXIT;
+ goto out_err;
+ }
+
+ if (!namestr || !devstr) {
+ printk("snapfs: mount options name and dev mandatory\n");
+ EXIT;
+ goto out_err;
+ }
+
+ err = snapfs_path2dev(devstr, &dev);
+ if ( err ) {
+ printk("snap: incorrect device option %s\n", devstr);
+ EXIT;
+ goto out_err;
+ }
+
+ snap_cache = snap_find_cache(dev);
+ if ( !snap_cache ) {
+ printk("snap: incorrect device option %s\n", devstr);
+ EXIT;
+ goto out_err;
+ }
+
+ /*index = simple_strtoul(indexstr, &endptr, 0);
+ if ( indexstr == endptr ) {
+ printk("No valid index passed to mount\n");
+ EXIT;
+ goto out_err;
+ }
+ */
+
+ index = snap_get_index_from_name (snap_cache->cache_snap_tableno,
+ namestr);
+ CDEBUG(D_SUPER, "tableno %d, name %s, get index %d\n",
+ snap_cache->cache_snap_tableno, namestr, index);
+
+ if(index < 0 ) {
+ printk("No valid index for name %s passed to mount\n",namestr);
+ EXIT;
+ goto out_err;
+ }
+
+ /*
+ * Force clone fs to be read-only.
+ *
+ * XXX - Is there a way to change the mount options too so
+ * the fs is listed as RO by mount?
+ */
+ sb->s_flags |= MS_RDONLY;
+
+ /* set up the super block */
+ clone_sb = (struct snap_clone_info *)&sb->u.generic_sbp;
+ list_add(&clone_sb->clone_list_entry, &snap_cache->cache_clone_list);
+ clone_sb->clone_cache = snap_cache;
+ clone_sb->clone_index = index;
+ sb->s_op = &clone_super_ops;
+
+ root_ino = snap_cache->cache_sb->s_root->d_inode->i_ino;
+ root_inode = iget(sb, root_ino);
+
+ CDEBUG(D_SUPER, "readinode %p, root ino %ld, root inode at %p\n",
+ sb->s_op->read_inode, root_ino, root_inode);
+
+ sb->s_root = d_alloc_root(root_inode, NULL);
+ if (!sb->s_root) {
+ list_del(&clone_sb->clone_list_entry);
+ sb = NULL;
+ }
+
+ dget( snap_cache->cache_sb->s_root );
+
+ if (cache_data)
+ SNAP_FREE(cache_data, PAGE_SIZE);
+ if (devstr)
+ SNAP_FREE(devstr, strlen(devstr) + 1);
+ if (namestr)
+ SNAP_FREE(namestr, strlen(namestr) + 1);
+ CDEBUG(D_SUPER, "sb %lx, &sb->u.generic_sbp: %lx\n",
+ (ulong) sb, (ulong) &sb->u.generic_sbp);
+
+ MOD_INC_USE_COUNT;
+ EXIT;
+ return sb;
+ out_err:
+ CDEBUG(D_MALLOC, "mount error exit: kmem %ld, vmem %ld\n",
+ snap_kmemory, snap_vmemory);
+ return NULL;
+}
+
+
+struct file_system_type snapfs_clone_type = {
+ "snap_clone",
+ 0,
+ clone_read_super,
+ NULL
+};
+
+
+int init_snapfs(void)
+{
+ int status;
+
+ snap_init_cache_hash();
+
+ status = register_filesystem(&snapfs_current_type);
+ if (status) {
+ printk("snapfs: failed in register current filesystem!\n");
+ }
+ status = register_filesystem(&snapfs_clone_type);
+ if (status) {
+ unregister_filesystem(&snapfs_current_type);
+ printk("snapfs: failed in register clone filesystem!\n");
+ }
+ return status;
+}
+
+
+
+int cleanup_snapfs(void)
+{
+ int err;
+
+ ENTRY;
+
+ err = unregister_filesystem(&snapfs_clone_type);
+ if ( err ) {
+ printk("snapfs: failed to unregister clone filesystem\n");
+ }
+ err = unregister_filesystem(&snapfs_current_type);
+ if ( err ) {
+ printk("snapfs: failed to unregister filesystem\n");
+ }
+
+ return 0;
+}
diff --git a/lustre/snapfs/symlink.c b/lustre/snapfs/symlink.c
new file mode 100644
index 0000000000..41efbd1935
--- /dev/null
+++ b/lustre/snapfs/symlink.c
@@ -0,0 +1,213 @@
+/*
+ * fs/snap/snap.c
+ *
+ * A snap shot file system.
+ *
+ */
+
+#define EXPORT_SYMTAB
+
+
+#define __NO_VERSION__
+#include <linux/module.h>
+#include <asm/uaccess.h>
+#include <linux/sched.h>
+#include <linux/stat.h>
+#include <linux/string.h>
+#include <linux/locks.h>
+#include <linux/quotaops.h>
+#include <linux/list.h>
+#include <linux/file.h>
+#include <asm/bitops.h>
+#include <asm/byteorder.h>
+
+#include <linux/filter.h>
+#include <linux/snapfs.h>
+#include <linux/snapsupport.h>
+
+static inline int inode_has_ea(struct inode *inode)
+{
+ return (inode->u.ext2_i.i_file_acl != 0);
+}
+
+static int currentfs_readlink(struct dentry * dentry, char * buffer, int buflen)
+{
+ struct snap_cache *cache;
+ int rc;
+ struct inode_operations *iops;
+ struct inode * inode = dentry->d_inode;
+ int bpib = inode->i_sb->s_blocksize >> 9;
+ __u32 save_i_blocks;
+
+ ENTRY;
+
+ cache = snap_find_cache(inode->i_dev);
+ if ( !cache ) {
+ EXIT;
+ return -EINVAL;
+ }
+
+ iops = filter_c2csiops(cache->cache_filter);
+ if (!iops ||
+ !iops->readlink) {
+ rc = -EINVAL;
+ goto exit;
+ }
+
+ save_i_blocks = inode->i_blocks;
+ /* If this link has ea and its i_blocks is ea's block,
+ * then we should treate it as a fast symlink
+ */
+ if( inode_has_ea(inode) && inode->i_blocks == bpib ) {
+ inode->i_blocks = 0;
+ }
+ rc = iops->readlink(dentry, buffer, buflen);
+
+ if( inode->i_blocks != save_i_blocks ){
+ inode->i_blocks = save_i_blocks;
+ mark_inode_dirty(inode);
+ }
+
+exit:
+ EXIT;
+ return rc;
+}
+
+static int cat_str_ahead(char *buf, int pos, const char* str)
+{
+ int len = strlen(str);
+
+ if( pos - len -1 < 0 )
+ return pos;
+
+ buf[--pos] = '/';
+ memcpy(&buf[pos-len], str, len);
+ return pos-len;
+}
+
+/*
+ * Adjust the following path if we are under dotsnap (skip .snap/clonexx...)
+ * in following two case, we just return null and let caller do
+ * the normal follow_link:
+ * (1) we are not lies in .snap
+ * (2) we are already in the root's .snap
+ */
+static struct dentry * dotsnap_follow_link(struct dentry *base,
+ struct dentry *dentry,
+ int follow)
+{
+ struct super_block *sb = dentry->d_inode->i_sb;
+ struct dentry *rc = NULL;
+ struct dentry *de = dentry, *de_save1=NULL, *de_save2=NULL;
+ char *buf = NULL;
+ int pos = D_MAXLEN;
+
+ SNAP_ALLOC(buf, char*, D_MAXLEN);
+ if( !buf )
+ return ERR_PTR(-ENOMEM);
+
+ /*
+ * iterate upward to construct the path
+ */
+ do {
+ if( de_save2 )
+ pos = cat_str_ahead(buf, pos, de_save2->d_name.name);
+
+ if ( de->d_inode && de->d_inode->i_ino & 0xF0000000 )
+ goto lookup;
+
+ de_save2 = de_save1;
+ de_save1 = de;
+ de = de->d_parent;
+ } while (de->d_parent != de);
+
+ /* we are not under dotsnap */
+ goto exit;
+
+lookup:
+ /* See if we already under root's .snap */
+ de = de->d_parent;
+ if( de == sb->s_root )
+ goto exit;
+
+ while( (de->d_parent != de) && (de != sb->s_root) ){
+ pos = cat_str_ahead(buf, pos, de->d_name.name);
+ de = de->d_parent;
+ }
+ if( de_save1 )
+ pos = cat_str_ahead(buf, pos, de_save1->d_name.name);
+
+ pos = cat_str_ahead(buf, pos, ".snap");
+ buf[D_MAXLEN-1] = 0;
+ CDEBUG(D_FILE, "constructed path: %s\n", &buf[pos]);
+
+ /* FIXME lookup_dentry will never return NULL ?? */
+ rc = lookup_dentry(&buf[pos], dget(sb->s_root), follow);
+ if( !rc ){
+ rc = ERR_PTR(-ENOENT);
+ CDEBUG(D_FILE, "lookup_dentry return NULL~!@#$^&*\n");
+ }
+ dput(base);
+
+exit:
+ SNAP_FREE(buf, D_MAXLEN);
+ return rc;
+}
+
+static struct dentry * currentfs_follow_link ( struct dentry *dentry,
+ struct dentry *base,
+ unsigned int follow)
+{
+ struct snap_cache *cache;
+ struct dentry * rc;
+ struct inode_operations *iops;
+ struct inode * inode = dentry->d_inode;
+ int bpib = inode->i_sb->s_blocksize >> 9;
+ __u32 save_i_blocks;
+
+ ENTRY;
+
+ cache = snap_find_cache(inode->i_dev);
+ if ( !cache ) {
+ EXIT;
+ return ERR_PTR(-EINVAL);
+ }
+
+ iops = filter_c2csiops(cache->cache_filter);
+ if (!iops ||
+ !iops->follow_link) {
+ rc = ERR_PTR(-EINVAL);
+ goto exit;
+ }
+
+ if( currentfs_is_under_dotsnap(dentry) ){
+ rc = dotsnap_follow_link( base, dentry, follow );
+ if( rc )
+ goto exit;
+ }
+
+ save_i_blocks = inode->i_blocks;
+ /* If this link has ea and its i_blocks is ea's block,
+ * then we should treate it as a fast symlink
+ */
+ if( inode_has_ea(inode) && inode->i_blocks == bpib ) {
+ inode->i_blocks = 0;
+ }
+ rc = iops->follow_link(dentry, base, follow);
+
+ if( inode->i_blocks != save_i_blocks ){
+ inode->i_blocks = save_i_blocks;
+ mark_inode_dirty(inode);
+ }
+
+exit:
+ EXIT;
+ return rc;
+}
+
+struct inode_operations currentfs_sym_iops = {
+ readlink: currentfs_readlink,
+ follow_link: currentfs_follow_link
+};
+
+struct file_operations currentfs_sym_fops;
diff --git a/lustre/snapfs/sysctl.c b/lustre/snapfs/sysctl.c
new file mode 100644
index 0000000000..f7f88a6700
--- /dev/null
+++ b/lustre/snapfs/sysctl.c
@@ -0,0 +1,110 @@
+/*
+ * Sysctrl entries for Snapfs
+ */
+
+#define __NO_VERSION__
+#include <linux/config.h> /* for CONFIG_PROC_FS */
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/sysctl.h>
+#include <linux/swapctl.h>
+#include <linux/proc_fs.h>
+#include <linux/malloc.h>
+#include <linux/vmalloc.h>
+#include <linux/stat.h>
+#include <linux/ctype.h>
+#include <linux/init.h>
+#include <asm/bitops.h>
+#include <asm/segment.h>
+#include <asm/uaccess.h>
+#include <linux/utsname.h>
+#include <linux/blk.h>
+
+#include <linux/filter.h>
+#include <linux/snapfs.h>
+#include <linux/snapsupport.h>
+
+
+/* /proc entries */
+
+#ifdef CONFIG_PROC_FS
+
+
+static void snapfs_proc_modcount(struct inode *inode, int fill)
+{
+ if (fill)
+ MOD_INC_USE_COUNT;
+ else
+ MOD_DEC_USE_COUNT;
+}
+
+struct proc_dir_entry proc_fs_snapfs = {
+ 0, 10, "snapfs",
+ S_IFDIR | S_IRUGO | S_IXUGO, 2, 0, 0,
+ 0, &proc_dir_inode_operations,
+ NULL, NULL,
+ NULL,
+ NULL, NULL
+};
+
+
+#endif
+
+
+/* SYSCTL below */
+
+static struct ctl_table_header *snapfs_table_header = NULL;
+/* 0x100 to avoid any chance of collisions at any point in the tree with
+ * non-directories
+ */
+#define PSDEV_SNAPFS (0x120)
+
+#define PSDEV_DEBUG 1 /* control debugging */
+#define PSDEV_TRACE 2 /* control enter/leave pattern */
+
+/* These are global control options */
+#define ENTRY_CNT 3
+
+/* XXX - doesn't seem to be working in 2.2.15 */
+static struct ctl_table snapfs_ctltable[ENTRY_CNT] =
+{
+ {PSDEV_DEBUG, "debug", &snap_debug_level, sizeof(int), 0644, NULL, &proc_dointvec},
+ {PSDEV_TRACE, "trace", &snap_print_entry, sizeof(int), 0644, NULL, &proc_dointvec},
+ {0}
+};
+
+static ctl_table snapfs_table[2] = {
+ {PSDEV_SNAPFS, "snapfs", NULL, 0, 0555, snapfs_ctltable},
+ {0}
+};
+
+
+int /* __init */ init_snapfs_proc_sys(void)
+{
+
+#ifdef CONFIG_SYSCTL
+ if ( !snapfs_table_header )
+ snapfs_table_header =
+ register_sysctl_table(snapfs_table, 0);
+#endif
+#ifdef CONFIG_PROC_FS
+ proc_register(&proc_root_fs, &proc_fs_snapfs);
+ proc_fs_snapfs.fill_inode = &snapfs_proc_modcount;
+#endif
+ return 0;
+}
+
+void cleanup_snapfs_proc_sys(void) {
+
+#ifdef CONFIG_SYSCTL
+ if ( snapfs_table_header )
+ unregister_sysctl_table(snapfs_table_header);
+ snapfs_table_header = NULL;
+#endif
+
+#if CONFIG_PROC_FS
+ proc_unregister(&proc_root_fs, proc_fs_snapfs.low_ino);
+#endif
+}
+
--
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