fs/jfs/super.c - fp2-dev/kernel/msm - Gitiles

 /*
  *   Copyright (C) International Business Machines Corp., 2000-2004
  *   Portions Copyright (C) Christoph Hellwig, 2001-2002
  *
  *   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.
  *
  *   This program is distributed in the hope that it will be useful,
  *   but WITHOUT ANY WARRANTY;  without even the implied warranty of
  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
  *   the GNU General Public License for more details.
  *
  *   You should have received a copy of the GNU General Public License
  *   along with this program;  if not, write to the Free Software
  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  */

 #include <linux/fs.h>
 #include <linux/config.h>
 #include <linux/module.h>
 #include <linux/parser.h>
 #include <linux/completion.h>
 #include <linux/vfs.h>
 #include <linux/moduleparam.h>
 #include <linux/posix_acl.h>
 #include <asm/uaccess.h>

 #include "jfs_incore.h"
 #include "jfs_filsys.h"
 #include "jfs_inode.h"
 #include "jfs_metapage.h"
 #include "jfs_superblock.h"
 #include "jfs_dmap.h"
 #include "jfs_imap.h"
 #include "jfs_acl.h"
 #include "jfs_debug.h"

 MODULE_DESCRIPTION("The Journaled Filesystem (JFS)");
 MODULE_AUTHOR("Steve Best/Dave Kleikamp/Barry Arndt, IBM");
 MODULE_LICENSE("GPL");

 static kmem_cache_t * jfs_inode_cachep;

 static struct super_operations jfs_super_operations;
 static struct export_operations jfs_export_operations;
 static struct file_system_type jfs_fs_type;

 #define MAX_COMMIT_THREADS 64
 static int commit_threads = 0;
 module_param(commit_threads, int, 0);
 MODULE_PARM_DESC(commit_threads, "Number of commit threads");

 int jfs_stop_threads;
 static pid_t jfsIOthread;
 static pid_t jfsCommitThread[MAX_COMMIT_THREADS];
 static pid_t jfsSyncThread;
 DECLARE_COMPLETION(jfsIOwait);

 #ifdef CONFIG_JFS_DEBUG
 int jfsloglevel = JFS_LOGLEVEL_WARN;
 module_param(jfsloglevel, int, 0644);
 MODULE_PARM_DESC(jfsloglevel, "Specify JFS loglevel (0, 1 or 2)");
 #endif

 static void jfs_handle_error(struct super_block *sb)
 {
 	struct jfs_sb_info *sbi = JFS_SBI(sb);

 	if (sb->s_flags & MS_RDONLY)
 		return;

 	updateSuper(sb, FM_DIRTY);

 	if (sbi->flag & JFS_ERR_PANIC)
 		panic("JFS (device %s): panic forced after error\n",
 			sb->s_id);
 	else if (sbi->flag & JFS_ERR_REMOUNT_RO) {
 		jfs_err("ERROR: (device %s): remounting filesystem "
 			"as read-only\n",
 			sb->s_id);
 		sb->s_flags |= MS_RDONLY;
 	}

 	/* nothing is done for continue beyond marking the superblock dirty */
 }

 void jfs_error(struct super_block *sb, const char * function, ...)
 {
 	static char error_buf[256];
 	va_list args;

 	va_start(args, function);
 	vsprintf(error_buf, function, args);
 	va_end(args);

 	printk(KERN_ERR "ERROR: (device %s): %s\n", sb->s_id, error_buf);

 	jfs_handle_error(sb);
 }

 static struct inode *jfs_alloc_inode(struct super_block *sb)
 {
 	struct jfs_inode_info *jfs_inode;

 	jfs_inode = kmem_cache_alloc(jfs_inode_cachep, GFP_NOFS);
 	if (!jfs_inode)
 		return NULL;
 	return &jfs_inode->vfs_inode;
 }

 static void jfs_destroy_inode(struct inode *inode)
 {
 	struct jfs_inode_info *ji = JFS_IP(inode);

 	BUG_ON(!list_empty(&ji->anon_inode_list));

 	spin_lock_irq(&ji->ag_lock);
 	if (ji->active_ag != -1) {
 		struct bmap *bmap = JFS_SBI(inode->i_sb)->bmap;
 		atomic_dec(&bmap->db_active[ji->active_ag]);
 		ji->active_ag = -1;
 	}
 	spin_unlock_irq(&ji->ag_lock);

 #ifdef CONFIG_JFS_POSIX_ACL
 	if (ji->i_acl != JFS_ACL_NOT_CACHED) {
 		posix_acl_release(ji->i_acl);
 		ji->i_acl = JFS_ACL_NOT_CACHED;
 	}
 	if (ji->i_default_acl != JFS_ACL_NOT_CACHED) {
 		posix_acl_release(ji->i_default_acl);
 		ji->i_default_acl = JFS_ACL_NOT_CACHED;
 	}
 #endif

 	kmem_cache_free(jfs_inode_cachep, ji);
 }

 static int jfs_statfs(struct super_block *sb, struct kstatfs *buf)
 {
 	struct jfs_sb_info *sbi = JFS_SBI(sb);
 	s64 maxinodes;
 	struct inomap *imap = JFS_IP(sbi->ipimap)->i_imap;

 	jfs_info("In jfs_statfs");
 	buf->f_type = JFS_SUPER_MAGIC;
 	buf->f_bsize = sbi->bsize;
 	buf->f_blocks = sbi->bmap->db_mapsize;
 	buf->f_bfree = sbi->bmap->db_nfree;
 	buf->f_bavail = sbi->bmap->db_nfree;
 	/*
 	 * If we really return the number of allocated & free inodes, some
 	 * applications will fail because they won't see enough free inodes.
 	 * We'll try to calculate some guess as to how may inodes we can
 	 * really allocate
 	 *
 	 * buf->f_files = atomic_read(&imap->im_numinos);
 	 * buf->f_ffree = atomic_read(&imap->im_numfree);
 	 */
 	maxinodes = min((s64) atomic_read(&imap->im_numinos) +
 			((sbi->bmap->db_nfree >> imap->im_l2nbperiext)
 			 << L2INOSPEREXT), (s64) 0xffffffffLL);
 	buf->f_files = maxinodes;
 	buf->f_ffree = maxinodes - (atomic_read(&imap->im_numinos) -
 				    atomic_read(&imap->im_numfree));

 	buf->f_namelen = JFS_NAME_MAX;
 	return 0;
 }

 static void jfs_put_super(struct super_block *sb)
 {
 	struct jfs_sb_info *sbi = JFS_SBI(sb);
 	int rc;

 	jfs_info("In jfs_put_super");
 	rc = jfs_umount(sb);
 	if (rc)
 		jfs_err("jfs_umount failed with return code %d", rc);
 	if (sbi->nls_tab)
 		unload_nls(sbi->nls_tab);
 	sbi->nls_tab = NULL;

 	truncate_inode_pages(sbi->direct_inode->i_mapping, 0);
 	iput(sbi->direct_inode);
 	sbi->direct_inode = NULL;

 	kfree(sbi);
 }

 enum {
 	Opt_integrity, Opt_nointegrity, Opt_iocharset, Opt_resize,
 	Opt_resize_nosize, Opt_errors, Opt_ignore, Opt_err,
 };

 static match_table_t tokens = {
 	{Opt_integrity, "integrity"},
 	{Opt_nointegrity, "nointegrity"},
 	{Opt_iocharset, "iocharset=%s"},
 	{Opt_resize, "resize=%u"},
 	{Opt_resize_nosize, "resize"},
 	{Opt_errors, "errors=%s"},
 	{Opt_ignore, "noquota"},
 	{Opt_ignore, "quota"},
 	{Opt_ignore, "usrquota"},
 	{Opt_ignore, "grpquota"},
 	{Opt_err, NULL}
 };

 static int parse_options(char *options, struct super_block *sb, s64 *newLVSize,
 			 int *flag)
 {
 	void *nls_map = (void *)-1;	/* -1: no change;  NULL: none */
 	char *p;
 	struct jfs_sb_info *sbi = JFS_SBI(sb);

 	*newLVSize = 0;

 	if (!options)
 		return 1;

 	while ((p = strsep(&options, ",")) != NULL) {
 		substring_t args[MAX_OPT_ARGS];
 		int token;
 		if (!*p)
 			continue;

 		token = match_token(p, tokens, args);
 		switch (token) {
 		case Opt_integrity:
 			*flag &= ~JFS_NOINTEGRITY;
 			break;
 		case Opt_nointegrity:
 			*flag |= JFS_NOINTEGRITY;
 			break;
 		case Opt_ignore:
 			/* Silently ignore the quota options */
 			/* Don't do anything ;-) */
 			break;
 		case Opt_iocharset:
 			if (nls_map && nls_map != (void *) -1)
 				unload_nls(nls_map);
 			if (!strcmp(args[0].from, "none"))
 				nls_map = NULL;
 			else {
 				nls_map = load_nls(args[0].from);
 				if (!nls_map) {
 					printk(KERN_ERR
 					       "JFS: charset not found\n");
 					goto cleanup;
 				}
 			}
 			break;
 		case Opt_resize:
 		{
 			char *resize = args[0].from;
 			*newLVSize = simple_strtoull(resize, &resize, 0);
 			break;
 		}
 		case Opt_resize_nosize:
 		{
 			*newLVSize = sb->s_bdev->bd_inode->i_size >>
 				sb->s_blocksize_bits;
 			if (*newLVSize == 0)
 				printk(KERN_ERR
 				       "JFS: Cannot determine volume size\n");
 			break;
 		}
 		case Opt_errors:
 		{
 			char *errors = args[0].from;
 			if (!errors || !*errors)
 				goto cleanup;
 			if (!strcmp(errors, "continue")) {
 				*flag &= ~JFS_ERR_REMOUNT_RO;
 				*flag &= ~JFS_ERR_PANIC;
 				*flag |= JFS_ERR_CONTINUE;
 			} else if (!strcmp(errors, "remount-ro")) {
 				*flag &= ~JFS_ERR_CONTINUE;
 				*flag &= ~JFS_ERR_PANIC;
 				*flag |= JFS_ERR_REMOUNT_RO;
 			} else if (!strcmp(errors, "panic")) {
 				*flag &= ~JFS_ERR_CONTINUE;
 				*flag &= ~JFS_ERR_REMOUNT_RO;
 				*flag |= JFS_ERR_PANIC;
 			} else {
 				printk(KERN_ERR
 				       "JFS: %s is an invalid error handler\n",
 				       errors);
 				goto cleanup;
 			}
 			break;
 		}
 		default:
 			printk("jfs: Unrecognized mount option \"%s\" "
 					" or missing value\n", p);
 			goto cleanup;
 		}
 	}

 	if (nls_map != (void *) -1) {
 		/* Discard old (if remount) */
 		if (sbi->nls_tab)
 			unload_nls(sbi->nls_tab);
 		sbi->nls_tab = nls_map;
 	}
 	return 1;

 cleanup:
 	if (nls_map && nls_map != (void *) -1)
 		unload_nls(nls_map);
 	return 0;
 }

 static int jfs_remount(struct super_block *sb, int *flags, char *data)
 {
 	s64 newLVSize = 0;
 	int rc = 0;
 	int flag = JFS_SBI(sb)->flag;

 	if (!parse_options(data, sb, &newLVSize, &flag)) {
 		return -EINVAL;
 	}
 	if (newLVSize) {
 		if (sb->s_flags & MS_RDONLY) {
 			printk(KERN_ERR
 		  "JFS: resize requires volume to be mounted read-write\n");
 			return -EROFS;
 		}
 		rc = jfs_extendfs(sb, newLVSize, 0);
 		if (rc)
 			return rc;
 	}

 	if ((sb->s_flags & MS_RDONLY) && !(*flags & MS_RDONLY)) {
 		/*
 		 * Invalidate any previously read metadata.  fsck may have
 		 * changed the on-disk data since we mounted r/o
 		 */
 		truncate_inode_pages(JFS_SBI(sb)->direct_inode->i_mapping, 0);

 		JFS_SBI(sb)->flag = flag;
 		return jfs_mount_rw(sb, 1);
 	}
 	if ((!(sb->s_flags & MS_RDONLY)) && (*flags & MS_RDONLY)) {
 		rc = jfs_umount_rw(sb);
 		JFS_SBI(sb)->flag = flag;
 		return rc;
 	}
 	if ((JFS_SBI(sb)->flag & JFS_NOINTEGRITY) != (flag & JFS_NOINTEGRITY))
 		if (!(sb->s_flags & MS_RDONLY)) {
 			rc = jfs_umount_rw(sb);
 			if (rc)
 				return rc;
 			JFS_SBI(sb)->flag = flag;
 			return jfs_mount_rw(sb, 1);
 		}
 	JFS_SBI(sb)->flag = flag;

 	return 0;
 }

 static int jfs_fill_super(struct super_block *sb, void *data, int silent)
 {
 	struct jfs_sb_info *sbi;
 	struct inode *inode;
 	int rc;
 	s64 newLVSize = 0;
 	int flag;

 	jfs_info("In jfs_read_super: s_flags=0x%lx", sb->s_flags);

 	if (!new_valid_dev(sb->s_bdev->bd_dev))
 		return -EOVERFLOW;

 	sbi = kmalloc(sizeof (struct jfs_sb_info), GFP_KERNEL);
 	if (!sbi)
 		return -ENOSPC;
 	memset(sbi, 0, sizeof (struct jfs_sb_info));
 	sb->s_fs_info = sbi;
 	sbi->sb = sb;

 	/* initialize the mount flag and determine the default error handler */
 	flag = JFS_ERR_REMOUNT_RO;

 	if (!parse_options((char *) data, sb, &newLVSize, &flag)) {
 		kfree(sbi);
 		return -EINVAL;
 	}
 	sbi->flag = flag;

 #ifdef CONFIG_JFS_POSIX_ACL
 	sb->s_flags |= MS_POSIXACL;
 #endif

 	if (newLVSize) {
 		printk(KERN_ERR "resize option for remount only\n");
 		return -EINVAL;
 	}

 	/*
 	 * Initialize blocksize to 4K.
 	 */
 	sb_set_blocksize(sb, PSIZE);

 	/*
 	 * Set method vectors.
 	 */
 	sb->s_op = &jfs_super_operations;
 	sb->s_export_op = &jfs_export_operations;

 	/*
 	 * Initialize direct-mapping inode/address-space
 	 */
 	inode = new_inode(sb);
 	if (inode == NULL)
 		goto out_kfree;
 	inode->i_ino = 0;
 	inode->i_nlink = 1;
 	inode->i_size = sb->s_bdev->bd_inode->i_size;
 	inode->i_mapping->a_ops = &jfs_metapage_aops;
 	mapping_set_gfp_mask(inode->i_mapping, GFP_NOFS);

 	sbi->direct_inode = inode;

 	rc = jfs_mount(sb);
 	if (rc) {
 		if (!silent) {
 			jfs_err("jfs_mount failed w/return code = %d", rc);
 		}
 		goto out_mount_failed;
 	}
 	if (sb->s_flags & MS_RDONLY)
 		sbi->log = NULL;
 	else {
 		rc = jfs_mount_rw(sb, 0);
 		if (rc) {
 			if (!silent) {
 				jfs_err("jfs_mount_rw failed, return code = %d",
 					rc);
 			}
 			goto out_no_rw;
 		}
 	}

 	sb->s_magic = JFS_SUPER_MAGIC;

 	inode = iget(sb, ROOT_I);
 	if (!inode || is_bad_inode(inode))
 		goto out_no_root;
 	sb->s_root = d_alloc_root(inode);
 	if (!sb->s_root)
 		goto out_no_root;

 	if (sbi->mntflag & JFS_OS2)
 		sb->s_root->d_op = &jfs_ci_dentry_operations;

 	/* logical blocks are represented by 40 bits in pxd_t, etc. */
 	sb->s_maxbytes = ((u64) sb->s_blocksize) << 40;
 #if BITS_PER_LONG == 32
 	/*
 	 * Page cache is indexed by long.
 	 * I would use MAX_LFS_FILESIZE, but it's only half as big
 	 */
 	sb->s_maxbytes = min(((u64) PAGE_CACHE_SIZE << 32) - 1, sb->s_maxbytes);
 #endif
 	sb->s_time_gran = 1;
 	return 0;

 out_no_root:
 	jfs_err("jfs_read_super: get root inode failed");
 	if (inode)
 		iput(inode);

 out_no_rw:
 	rc = jfs_umount(sb);
 	if (rc) {
 		jfs_err("jfs_umount failed with return code %d", rc);
 	}
 out_mount_failed:
 	filemap_fdatawrite(sbi->direct_inode->i_mapping);
 	filemap_fdatawait(sbi->direct_inode->i_mapping);
 	truncate_inode_pages(sbi->direct_inode->i_mapping, 0);
 	make_bad_inode(sbi->direct_inode);
 	iput(sbi->direct_inode);
 	sbi->direct_inode = NULL;
 out_kfree:
 	if (sbi->nls_tab)
 		unload_nls(sbi->nls_tab);
 	kfree(sbi);
 	return -EINVAL;
 }

 static void jfs_write_super_lockfs(struct super_block *sb)
 {
 	struct jfs_sb_info *sbi = JFS_SBI(sb);
 	struct jfs_log *log = sbi->log;

 	if (!(sb->s_flags & MS_RDONLY)) {
 		txQuiesce(sb);
 		lmLogShutdown(log);
 		updateSuper(sb, FM_CLEAN);
 	}
 }

 static void jfs_unlockfs(struct super_block *sb)
 {
 	struct jfs_sb_info *sbi = JFS_SBI(sb);
 	struct jfs_log *log = sbi->log;
 	int rc = 0;

 	if (!(sb->s_flags & MS_RDONLY)) {
 		updateSuper(sb, FM_MOUNT);
 		if ((rc = lmLogInit(log)))
 			jfs_err("jfs_unlock failed with return code %d", rc);
 		else
 			txResume(sb);
 	}
 }

 static struct super_block *jfs_get_sb(struct file_system_type *fs_type,
 	int flags, const char *dev_name, void *data)
 {
 	return get_sb_bdev(fs_type, flags, dev_name, data, jfs_fill_super);
 }

 static int jfs_sync_fs(struct super_block *sb, int wait)
 {
 	struct jfs_log *log = JFS_SBI(sb)->log;

 	/* log == NULL indicates read-only mount */
 	if (log) {
 		jfs_flush_journal(log, wait);
 		jfs_syncpt(log, 0);
 	}

 	return 0;
 }

 static struct super_operations jfs_super_operations = {
 	.alloc_inode	= jfs_alloc_inode,
 	.destroy_inode	= jfs_destroy_inode,
 	.read_inode	= jfs_read_inode,
 	.dirty_inode	= jfs_dirty_inode,
 	.write_inode	= jfs_write_inode,
 	.delete_inode	= jfs_delete_inode,
 	.put_super	= jfs_put_super,
 	.sync_fs	= jfs_sync_fs,
 	.write_super_lockfs = jfs_write_super_lockfs,
 	.unlockfs       = jfs_unlockfs,
 	.statfs		= jfs_statfs,
 	.remount_fs	= jfs_remount,
 };

 static struct export_operations jfs_export_operations = {
 	.get_parent	= jfs_get_parent,
 };

 static struct file_system_type jfs_fs_type = {
 	.owner		= THIS_MODULE,
 	.name		= "jfs",
 	.get_sb		= jfs_get_sb,
 	.kill_sb	= kill_block_super,
 	.fs_flags	= FS_REQUIRES_DEV,
 };

 static void init_once(void *foo, kmem_cache_t * cachep, unsigned long flags)
 {
 	struct jfs_inode_info *jfs_ip = (struct jfs_inode_info *) foo;

 	if ((flags & (SLAB_CTOR_VERIFY | SLAB_CTOR_CONSTRUCTOR)) ==
 	    SLAB_CTOR_CONSTRUCTOR) {
 		memset(jfs_ip, 0, sizeof(struct jfs_inode_info));
 		INIT_LIST_HEAD(&jfs_ip->anon_inode_list);
 		init_rwsem(&jfs_ip->rdwrlock);
 		init_MUTEX(&jfs_ip->commit_sem);
 		init_rwsem(&jfs_ip->xattr_sem);
 		spin_lock_init(&jfs_ip->ag_lock);
 		jfs_ip->active_ag = -1;
 #ifdef CONFIG_JFS_POSIX_ACL
 		jfs_ip->i_acl = JFS_ACL_NOT_CACHED;
 		jfs_ip->i_default_acl = JFS_ACL_NOT_CACHED;
 #endif
 		inode_init_once(&jfs_ip->vfs_inode);
 	}
 }

 static int __init init_jfs_fs(void)
 {
 	int i;
 	int rc;

 	jfs_inode_cachep =
 	    kmem_cache_create("jfs_ip", sizeof(struct jfs_inode_info), 0,
 			    SLAB_RECLAIM_ACCOUNT, init_once, NULL);
 	if (jfs_inode_cachep == NULL)
 		return -ENOMEM;

 	/*
 	 * Metapage initialization
 	 */
 	rc = metapage_init();
 	if (rc) {
 		jfs_err("metapage_init failed w/rc = %d", rc);
 		goto free_slab;
 	}

 	/*
 	 * Transaction Manager initialization
 	 */
 	rc = txInit();
 	if (rc) {
 		jfs_err("txInit failed w/rc = %d", rc);
 		goto free_metapage;
 	}

 	/*
 	 * I/O completion thread (endio)
 	 */
 	jfsIOthread = kernel_thread(jfsIOWait, NULL, CLONE_KERNEL);
 	if (jfsIOthread < 0) {
 		jfs_err("init_jfs_fs: fork failed w/rc = %d", jfsIOthread);
 		goto end_txmngr;
 	}
 	wait_for_completion(&jfsIOwait);	/* Wait until thread starts */

 	if (commit_threads < 1)
 		commit_threads = num_online_cpus();
 	if (commit_threads > MAX_COMMIT_THREADS)
 		commit_threads = MAX_COMMIT_THREADS;

 	for (i = 0; i < commit_threads; i++) {
 		jfsCommitThread[i] = kernel_thread(jfs_lazycommit, NULL,
 						   CLONE_KERNEL);
 		if (jfsCommitThread[i] < 0) {
 			jfs_err("init_jfs_fs: fork failed w/rc = %d",
 				jfsCommitThread[i]);
 			commit_threads = i;
 			goto kill_committask;
 		}
 		/* Wait until thread starts */
 		wait_for_completion(&jfsIOwait);
 	}

 	jfsSyncThread = kernel_thread(jfs_sync, NULL, CLONE_KERNEL);
 	if (jfsSyncThread < 0) {
 		jfs_err("init_jfs_fs: fork failed w/rc = %d", jfsSyncThread);
 		goto kill_committask;
 	}
 	wait_for_completion(&jfsIOwait);	/* Wait until thread starts */

 #ifdef PROC_FS_JFS
 	jfs_proc_init();
 #endif

 	return register_filesystem(&jfs_fs_type);

 kill_committask:
 	jfs_stop_threads = 1;
 	wake_up_all(&jfs_commit_thread_wait);
 	for (i = 0; i < commit_threads; i++)
 		wait_for_completion(&jfsIOwait);

 	wake_up(&jfs_IO_thread_wait);
 	wait_for_completion(&jfsIOwait);	/* Wait for thread exit */
 end_txmngr:
 	txExit();
 free_metapage:
 	metapage_exit();
 free_slab:
 	kmem_cache_destroy(jfs_inode_cachep);
 	return rc;
 }

 static void __exit exit_jfs_fs(void)
 {
 	int i;

 	jfs_info("exit_jfs_fs called");

 	jfs_stop_threads = 1;
 	txExit();
 	metapage_exit();
 	wake_up(&jfs_IO_thread_wait);
 	wait_for_completion(&jfsIOwait);	/* Wait until IO thread exits */
 	wake_up_all(&jfs_commit_thread_wait);
 	for (i = 0; i < commit_threads; i++)
 		wait_for_completion(&jfsIOwait);
 	wake_up(&jfs_sync_thread_wait);
 	wait_for_completion(&jfsIOwait);	/* Wait until Sync thread exits */
 #ifdef PROC_FS_JFS
 	jfs_proc_clean();
 #endif
 	unregister_filesystem(&jfs_fs_type);
 	kmem_cache_destroy(jfs_inode_cachep);
 }

 module_init(init_jfs_fs)
 module_exit(exit_jfs_fs)
	/*
	* Copyright (C) International Business Machines Corp., 2000-2004
	* Portions Copyright (C) Christoph Hellwig, 2001-2002
	*
	* 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.
	*
	* This program is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
	* the GNU General Public License for more details.
	*
	* You should have received a copy of the GNU General Public License
	* along with this program; if not, write to the Free Software
	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	*/

	#include <linux/fs.h>
	#include <linux/config.h>
	#include <linux/module.h>
	#include <linux/parser.h>
	#include <linux/completion.h>
	#include <linux/vfs.h>
	#include <linux/moduleparam.h>
	#include <linux/posix_acl.h>
	#include <asm/uaccess.h>

	#include "jfs_incore.h"
	#include "jfs_filsys.h"
	#include "jfs_inode.h"
	#include "jfs_metapage.h"
	#include "jfs_superblock.h"
	#include "jfs_dmap.h"
	#include "jfs_imap.h"
	#include "jfs_acl.h"
	#include "jfs_debug.h"

	MODULE_DESCRIPTION("The Journaled Filesystem (JFS)");
	MODULE_AUTHOR("Steve Best/Dave Kleikamp/Barry Arndt, IBM");
	MODULE_LICENSE("GPL");

	static kmem_cache_t * jfs_inode_cachep;

	static struct super_operations jfs_super_operations;
	static struct export_operations jfs_export_operations;
	static struct file_system_type jfs_fs_type;

	#define MAX_COMMIT_THREADS 64
	static int commit_threads = 0;
	module_param(commit_threads, int, 0);
	MODULE_PARM_DESC(commit_threads, "Number of commit threads");

	int jfs_stop_threads;
	static pid_t jfsIOthread;
	static pid_t jfsCommitThread[MAX_COMMIT_THREADS];
	static pid_t jfsSyncThread;
	DECLARE_COMPLETION(jfsIOwait);

	#ifdef CONFIG_JFS_DEBUG
	int jfsloglevel = JFS_LOGLEVEL_WARN;
	module_param(jfsloglevel, int, 0644);
	MODULE_PARM_DESC(jfsloglevel, "Specify JFS loglevel (0, 1 or 2)");
	#endif

	static void jfs_handle_error(struct super_block *sb)
	{
	struct jfs_sb_info *sbi = JFS_SBI(sb);

	if (sb->s_flags & MS_RDONLY)
	return;

	updateSuper(sb, FM_DIRTY);

	if (sbi->flag & JFS_ERR_PANIC)
	panic("JFS (device %s): panic forced after error\n",
	sb->s_id);
	else if (sbi->flag & JFS_ERR_REMOUNT_RO) {
	jfs_err("ERROR: (device %s): remounting filesystem "
	"as read-only\n",
	sb->s_id);
	sb->s_flags \|= MS_RDONLY;
	}

	/* nothing is done for continue beyond marking the superblock dirty */
	}

	void jfs_error(struct super_block sb, const char function, ...)
	{
	static char error_buf[256];
	va_list args;

	va_start(args, function);
	vsprintf(error_buf, function, args);
	va_end(args);

	printk(KERN_ERR "ERROR: (device %s): %s\n", sb->s_id, error_buf);

	jfs_handle_error(sb);
	}

	static struct inode jfs_alloc_inode(struct super_block sb)
	{
	struct jfs_inode_info *jfs_inode;

	jfs_inode = kmem_cache_alloc(jfs_inode_cachep, GFP_NOFS);
	if (!jfs_inode)
	return NULL;
	return &jfs_inode->vfs_inode;
	}

	static void jfs_destroy_inode(struct inode *inode)
	{
	struct jfs_inode_info *ji = JFS_IP(inode);

	BUG_ON(!list_empty(&ji->anon_inode_list));

	spin_lock_irq(&ji->ag_lock);
	if (ji->active_ag != -1) {
	struct bmap *bmap = JFS_SBI(inode->i_sb)->bmap;
	atomic_dec(&bmap->db_active[ji->active_ag]);
	ji->active_ag = -1;
	}
	spin_unlock_irq(&ji->ag_lock);

	#ifdef CONFIG_JFS_POSIX_ACL
	if (ji->i_acl != JFS_ACL_NOT_CACHED) {
	posix_acl_release(ji->i_acl);
	ji->i_acl = JFS_ACL_NOT_CACHED;
	}
	if (ji->i_default_acl != JFS_ACL_NOT_CACHED) {
	posix_acl_release(ji->i_default_acl);
	ji->i_default_acl = JFS_ACL_NOT_CACHED;
	}
	#endif

	kmem_cache_free(jfs_inode_cachep, ji);
	}

	static int jfs_statfs(struct super_block sb, struct kstatfs buf)
	{
	struct jfs_sb_info *sbi = JFS_SBI(sb);
	s64 maxinodes;
	struct inomap *imap = JFS_IP(sbi->ipimap)->i_imap;

	jfs_info("In jfs_statfs");
	buf->f_type = JFS_SUPER_MAGIC;
	buf->f_bsize = sbi->bsize;
	buf->f_blocks = sbi->bmap->db_mapsize;
	buf->f_bfree = sbi->bmap->db_nfree;
	buf->f_bavail = sbi->bmap->db_nfree;
	/*
	* If we really return the number of allocated & free inodes, some
	* applications will fail because they won't see enough free inodes.
	* We'll try to calculate some guess as to how may inodes we can
	* really allocate
	*
	* buf->f_files = atomic_read(&imap->im_numinos);
	* buf->f_ffree = atomic_read(&imap->im_numfree);
	*/
	maxinodes = min((s64) atomic_read(&imap->im_numinos) +
	((sbi->bmap->db_nfree >> imap->im_l2nbperiext)
	<< L2INOSPEREXT), (s64) 0xffffffffLL);
	buf->f_files = maxinodes;
	buf->f_ffree = maxinodes - (atomic_read(&imap->im_numinos) -
	atomic_read(&imap->im_numfree));

	buf->f_namelen = JFS_NAME_MAX;
	return 0;
	}

	static void jfs_put_super(struct super_block *sb)
	{
	struct jfs_sb_info *sbi = JFS_SBI(sb);
	int rc;

	jfs_info("In jfs_put_super");
	rc = jfs_umount(sb);
	if (rc)
	jfs_err("jfs_umount failed with return code %d", rc);
	if (sbi->nls_tab)
	unload_nls(sbi->nls_tab);
	sbi->nls_tab = NULL;

	truncate_inode_pages(sbi->direct_inode->i_mapping, 0);
	iput(sbi->direct_inode);
	sbi->direct_inode = NULL;

	kfree(sbi);
	}

	enum {
	Opt_integrity, Opt_nointegrity, Opt_iocharset, Opt_resize,
	Opt_resize_nosize, Opt_errors, Opt_ignore, Opt_err,
	};

	static match_table_t tokens = {
	{Opt_integrity, "integrity"},
	{Opt_nointegrity, "nointegrity"},
	{Opt_iocharset, "iocharset=%s"},
	{Opt_resize, "resize=%u"},
	{Opt_resize_nosize, "resize"},
	{Opt_errors, "errors=%s"},
	{Opt_ignore, "noquota"},
	{Opt_ignore, "quota"},
	{Opt_ignore, "usrquota"},
	{Opt_ignore, "grpquota"},
	{Opt_err, NULL}
	};

	static int parse_options(char options, struct super_block sb, s64 *newLVSize,
	int *flag)
	{
	void nls_map = (void )-1; /* -1: no change; NULL: none */
	char *p;
	struct jfs_sb_info *sbi = JFS_SBI(sb);

	*newLVSize = 0;

	if (!options)
	return 1;

	while ((p = strsep(&options, ",")) != NULL) {
	substring_t args[MAX_OPT_ARGS];
	int token;
	if (!*p)
	continue;

	token = match_token(p, tokens, args);
	switch (token) {
	case Opt_integrity:
	*flag &= ~JFS_NOINTEGRITY;
	break;
	case Opt_nointegrity:
	*flag \|= JFS_NOINTEGRITY;
	break;
	case Opt_ignore:
	/* Silently ignore the quota options */
	/* Don't do anything ;-) */
	break;
	case Opt_iocharset:
	if (nls_map && nls_map != (void *) -1)
	unload_nls(nls_map);
	if (!strcmp(args[0].from, "none"))
	nls_map = NULL;
	else {
	nls_map = load_nls(args[0].from);
	if (!nls_map) {
	printk(KERN_ERR
	"JFS: charset not found\n");
	goto cleanup;
	}
	}
	break;
	case Opt_resize:
	{
	char *resize = args[0].from;
	*newLVSize = simple_strtoull(resize, &resize, 0);
	break;
	}
	case Opt_resize_nosize:
	{
	*newLVSize = sb->s_bdev->bd_inode->i_size >>
	sb->s_blocksize_bits;
	if (*newLVSize == 0)
	printk(KERN_ERR
	"JFS: Cannot determine volume size\n");
	break;
	}
	case Opt_errors:
	{
	char *errors = args[0].from;
	if (!errors \|\| !*errors)
	goto cleanup;
	if (!strcmp(errors, "continue")) {
	*flag &= ~JFS_ERR_REMOUNT_RO;
	*flag &= ~JFS_ERR_PANIC;
	*flag \|= JFS_ERR_CONTINUE;
	} else if (!strcmp(errors, "remount-ro")) {
	*flag &= ~JFS_ERR_CONTINUE;
	*flag &= ~JFS_ERR_PANIC;
	*flag \|= JFS_ERR_REMOUNT_RO;
	} else if (!strcmp(errors, "panic")) {
	*flag &= ~JFS_ERR_CONTINUE;
	*flag &= ~JFS_ERR_REMOUNT_RO;
	*flag \|= JFS_ERR_PANIC;
	} else {
	printk(KERN_ERR
	"JFS: %s is an invalid error handler\n",
	errors);
	goto cleanup;
	}
	break;
	}
	default:
	printk("jfs: Unrecognized mount option \"%s\" "
	" or missing value\n", p);
	goto cleanup;
	}
	}

	if (nls_map != (void *) -1) {
	/* Discard old (if remount) */
	if (sbi->nls_tab)
	unload_nls(sbi->nls_tab);
	sbi->nls_tab = nls_map;
	}
	return 1;

	cleanup:
	if (nls_map && nls_map != (void *) -1)
	unload_nls(nls_map);
	return 0;
	}

	static int jfs_remount(struct super_block sb, int flags, char *data)
	{
	s64 newLVSize = 0;
	int rc = 0;
	int flag = JFS_SBI(sb)->flag;

	if (!parse_options(data, sb, &newLVSize, &flag)) {
	return -EINVAL;
	}
	if (newLVSize) {
	if (sb->s_flags & MS_RDONLY) {
	printk(KERN_ERR
	"JFS: resize requires volume to be mounted read-write\n");
	return -EROFS;
	}
	rc = jfs_extendfs(sb, newLVSize, 0);
	if (rc)
	return rc;
	}

	if ((sb->s_flags & MS_RDONLY) && !(*flags & MS_RDONLY)) {
	/*
	* Invalidate any previously read metadata. fsck may have
	* changed the on-disk data since we mounted r/o
	*/
	truncate_inode_pages(JFS_SBI(sb)->direct_inode->i_mapping, 0);

	JFS_SBI(sb)->flag = flag;
	return jfs_mount_rw(sb, 1);
	}
	if ((!(sb->s_flags & MS_RDONLY)) && (*flags & MS_RDONLY)) {
	rc = jfs_umount_rw(sb);
	JFS_SBI(sb)->flag = flag;
	return rc;
	}
	if ((JFS_SBI(sb)->flag & JFS_NOINTEGRITY) != (flag & JFS_NOINTEGRITY))
	if (!(sb->s_flags & MS_RDONLY)) {
	rc = jfs_umount_rw(sb);
	if (rc)
	return rc;
	JFS_SBI(sb)->flag = flag;
	return jfs_mount_rw(sb, 1);
	}
	JFS_SBI(sb)->flag = flag;

	return 0;
	}

	static int jfs_fill_super(struct super_block sb, void data, int silent)
	{
	struct jfs_sb_info *sbi;
	struct inode *inode;
	int rc;
	s64 newLVSize = 0;
	int flag;

	jfs_info("In jfs_read_super: s_flags=0x%lx", sb->s_flags);

	if (!new_valid_dev(sb->s_bdev->bd_dev))
	return -EOVERFLOW;

	sbi = kmalloc(sizeof (struct jfs_sb_info), GFP_KERNEL);
	if (!sbi)
	return -ENOSPC;
	memset(sbi, 0, sizeof (struct jfs_sb_info));
	sb->s_fs_info = sbi;
	sbi->sb = sb;

	/* initialize the mount flag and determine the default error handler */
	flag = JFS_ERR_REMOUNT_RO;

	if (!parse_options((char *) data, sb, &newLVSize, &flag)) {
	kfree(sbi);
	return -EINVAL;
	}
	sbi->flag = flag;

	#ifdef CONFIG_JFS_POSIX_ACL
	sb->s_flags \|= MS_POSIXACL;
	#endif

	if (newLVSize) {
	printk(KERN_ERR "resize option for remount only\n");
	return -EINVAL;
	}

	/*
	* Initialize blocksize to 4K.
	*/
	sb_set_blocksize(sb, PSIZE);

	/*
	* Set method vectors.
	*/
	sb->s_op = &jfs_super_operations;
	sb->s_export_op = &jfs_export_operations;

	/*
	* Initialize direct-mapping inode/address-space
	*/
	inode = new_inode(sb);
	if (inode == NULL)
	goto out_kfree;
	inode->i_ino = 0;
	inode->i_nlink = 1;
	inode->i_size = sb->s_bdev->bd_inode->i_size;
	inode->i_mapping->a_ops = &jfs_metapage_aops;
	mapping_set_gfp_mask(inode->i_mapping, GFP_NOFS);

	sbi->direct_inode = inode;

	rc = jfs_mount(sb);
	if (rc) {
	if (!silent) {
	jfs_err("jfs_mount failed w/return code = %d", rc);
	}
	goto out_mount_failed;
	}
	if (sb->s_flags & MS_RDONLY)
	sbi->log = NULL;
	else {
	rc = jfs_mount_rw(sb, 0);
	if (rc) {
	if (!silent) {
	jfs_err("jfs_mount_rw failed, return code = %d",
	rc);
	}
	goto out_no_rw;
	}
	}

	sb->s_magic = JFS_SUPER_MAGIC;

	inode = iget(sb, ROOT_I);
	if (!inode \|\| is_bad_inode(inode))
	goto out_no_root;
	sb->s_root = d_alloc_root(inode);
	if (!sb->s_root)
	goto out_no_root;

	if (sbi->mntflag & JFS_OS2)
	sb->s_root->d_op = &jfs_ci_dentry_operations;

	/* logical blocks are represented by 40 bits in pxd_t, etc. */
	sb->s_maxbytes = ((u64) sb->s_blocksize) << 40;
	#if BITS_PER_LONG == 32
	/*
	* Page cache is indexed by long.
	* I would use MAX_LFS_FILESIZE, but it's only half as big
	*/
	sb->s_maxbytes = min(((u64) PAGE_CACHE_SIZE << 32) - 1, sb->s_maxbytes);
	#endif
	sb->s_time_gran = 1;
	return 0;

	out_no_root:
	jfs_err("jfs_read_super: get root inode failed");
	if (inode)
	iput(inode);

	out_no_rw:
	rc = jfs_umount(sb);
	if (rc) {
	jfs_err("jfs_umount failed with return code %d", rc);
	}
	out_mount_failed:
	filemap_fdatawrite(sbi->direct_inode->i_mapping);
	filemap_fdatawait(sbi->direct_inode->i_mapping);
	truncate_inode_pages(sbi->direct_inode->i_mapping, 0);
	make_bad_inode(sbi->direct_inode);
	iput(sbi->direct_inode);
	sbi->direct_inode = NULL;
	out_kfree:
	if (sbi->nls_tab)
	unload_nls(sbi->nls_tab);
	kfree(sbi);
	return -EINVAL;
	}

	static void jfs_write_super_lockfs(struct super_block *sb)
	{
	struct jfs_sb_info *sbi = JFS_SBI(sb);
	struct jfs_log *log = sbi->log;

	if (!(sb->s_flags & MS_RDONLY)) {
	txQuiesce(sb);
	lmLogShutdown(log);
	updateSuper(sb, FM_CLEAN);
	}
	}

	static void jfs_unlockfs(struct super_block *sb)
	{
	struct jfs_sb_info *sbi = JFS_SBI(sb);
	struct jfs_log *log = sbi->log;
	int rc = 0;

	if (!(sb->s_flags & MS_RDONLY)) {
	updateSuper(sb, FM_MOUNT);
	if ((rc = lmLogInit(log)))
	jfs_err("jfs_unlock failed with return code %d", rc);
	else
	txResume(sb);
	}
	}

	static struct super_block jfs_get_sb(struct file_system_type fs_type,
	int flags, const char dev_name, void data)
	{
	return get_sb_bdev(fs_type, flags, dev_name, data, jfs_fill_super);
	}

	static int jfs_sync_fs(struct super_block *sb, int wait)
	{
	struct jfs_log *log = JFS_SBI(sb)->log;

	/* log == NULL indicates read-only mount */
	if (log) {
	jfs_flush_journal(log, wait);
	jfs_syncpt(log, 0);
	}

	return 0;
	}

	static struct super_operations jfs_super_operations = {
	.alloc_inode = jfs_alloc_inode,
	.destroy_inode = jfs_destroy_inode,
	.read_inode = jfs_read_inode,
	.dirty_inode = jfs_dirty_inode,
	.write_inode = jfs_write_inode,
	.delete_inode = jfs_delete_inode,
	.put_super = jfs_put_super,
	.sync_fs = jfs_sync_fs,
	.write_super_lockfs = jfs_write_super_lockfs,
	.unlockfs = jfs_unlockfs,
	.statfs = jfs_statfs,
	.remount_fs = jfs_remount,
	};

	static struct export_operations jfs_export_operations = {
	.get_parent = jfs_get_parent,
	};

	static struct file_system_type jfs_fs_type = {
	.owner = THIS_MODULE,
	.name = "jfs",
	.get_sb = jfs_get_sb,
	.kill_sb = kill_block_super,
	.fs_flags = FS_REQUIRES_DEV,
	};

	static void init_once(void foo, kmem_cache_t cachep, unsigned long flags)
	{
	struct jfs_inode_info jfs_ip = (struct jfs_inode_info ) foo;

	if ((flags & (SLAB_CTOR_VERIFY \| SLAB_CTOR_CONSTRUCTOR)) ==
	SLAB_CTOR_CONSTRUCTOR) {
	memset(jfs_ip, 0, sizeof(struct jfs_inode_info));
	INIT_LIST_HEAD(&jfs_ip->anon_inode_list);
	init_rwsem(&jfs_ip->rdwrlock);
	init_MUTEX(&jfs_ip->commit_sem);
	init_rwsem(&jfs_ip->xattr_sem);
	spin_lock_init(&jfs_ip->ag_lock);
	jfs_ip->active_ag = -1;
	#ifdef CONFIG_JFS_POSIX_ACL
	jfs_ip->i_acl = JFS_ACL_NOT_CACHED;
	jfs_ip->i_default_acl = JFS_ACL_NOT_CACHED;
	#endif
	inode_init_once(&jfs_ip->vfs_inode);
	}
	}

	static int __init init_jfs_fs(void)
	{
	int i;
	int rc;

	jfs_inode_cachep =
	kmem_cache_create("jfs_ip", sizeof(struct jfs_inode_info), 0,
	SLAB_RECLAIM_ACCOUNT, init_once, NULL);
	if (jfs_inode_cachep == NULL)
	return -ENOMEM;

	/*
	* Metapage initialization
	*/
	rc = metapage_init();
	if (rc) {
	jfs_err("metapage_init failed w/rc = %d", rc);
	goto free_slab;
	}

	/*
	* Transaction Manager initialization
	*/
	rc = txInit();
	if (rc) {
	jfs_err("txInit failed w/rc = %d", rc);
	goto free_metapage;
	}

	/*
	* I/O completion thread (endio)
	*/
	jfsIOthread = kernel_thread(jfsIOWait, NULL, CLONE_KERNEL);
	if (jfsIOthread < 0) {
	jfs_err("init_jfs_fs: fork failed w/rc = %d", jfsIOthread);
	goto end_txmngr;
	}
	wait_for_completion(&jfsIOwait); /* Wait until thread starts */

	if (commit_threads < 1)
	commit_threads = num_online_cpus();
	if (commit_threads > MAX_COMMIT_THREADS)
	commit_threads = MAX_COMMIT_THREADS;

	for (i = 0; i < commit_threads; i++) {
	jfsCommitThread[i] = kernel_thread(jfs_lazycommit, NULL,
	CLONE_KERNEL);
	if (jfsCommitThread[i] < 0) {
	jfs_err("init_jfs_fs: fork failed w/rc = %d",
	jfsCommitThread[i]);
	commit_threads = i;
	goto kill_committask;
	}
	/* Wait until thread starts */
	wait_for_completion(&jfsIOwait);
	}

	jfsSyncThread = kernel_thread(jfs_sync, NULL, CLONE_KERNEL);
	if (jfsSyncThread < 0) {
	jfs_err("init_jfs_fs: fork failed w/rc = %d", jfsSyncThread);
	goto kill_committask;
	}
	wait_for_completion(&jfsIOwait); /* Wait until thread starts */

	#ifdef PROC_FS_JFS
	jfs_proc_init();
	#endif

	return register_filesystem(&jfs_fs_type);

	kill_committask:
	jfs_stop_threads = 1;
	wake_up_all(&jfs_commit_thread_wait);
	for (i = 0; i < commit_threads; i++)
	wait_for_completion(&jfsIOwait);

	wake_up(&jfs_IO_thread_wait);
	wait_for_completion(&jfsIOwait); /* Wait for thread exit */
	end_txmngr:
	txExit();
	free_metapage:
	metapage_exit();
	free_slab:
	kmem_cache_destroy(jfs_inode_cachep);
	return rc;
	}

	static void __exit exit_jfs_fs(void)
	{
	int i;

	jfs_info("exit_jfs_fs called");

	jfs_stop_threads = 1;
	txExit();
	metapage_exit();
	wake_up(&jfs_IO_thread_wait);
	wait_for_completion(&jfsIOwait); /* Wait until IO thread exits */
	wake_up_all(&jfs_commit_thread_wait);
	for (i = 0; i < commit_threads; i++)
	wait_for_completion(&jfsIOwait);
	wake_up(&jfs_sync_thread_wait);
	wait_for_completion(&jfsIOwait); /* Wait until Sync thread exits */
	#ifdef PROC_FS_JFS
	jfs_proc_clean();
	#endif
	unregister_filesystem(&jfs_fs_type);
	kmem_cache_destroy(jfs_inode_cachep);
	}

	module_init(init_jfs_fs)
	module_exit(exit_jfs_fs)