1 files changed, 135 insertions, 93 deletions

diff --git a/fs/bfs/inode.c b/fs/bfs/inode.c
index 8db623838b5..7041ac35ace 100644
--- a/fs/bfs/inode.c
+++ b/fs/bfs/inode.c
@@ -12,9 +12,9 @@
 #include <linux/slab.h>
 #include <linux/init.h>
 #include <linux/fs.h>
-#include <linux/smp_lock.h>
 #include <linux/buffer_head.h>
 #include <linux/vfs.h>
+#include <linux/writeback.h>
 #include <asm/uaccess.h>
 #include "bfs.h"
 
@@ -40,7 +40,7 @@ struct inode *bfs_iget(struct super_block *sb, unsigned long ino)
 	int block, off;
 
 	inode = iget_locked(sb, ino);
-	if (IS_ERR(inode))
+	if (!inode)
 		return ERR_PTR(-ENOMEM);
 	if (!(inode->i_state & I_NEW))
 		return inode;
@@ -76,9 +76,9 @@ struct inode *bfs_iget(struct super_block *sb, unsigned long ino)
 	BFS_I(inode)->i_sblock =  le32_to_cpu(di->i_sblock);
 	BFS_I(inode)->i_eblock =  le32_to_cpu(di->i_eblock);
 	BFS_I(inode)->i_dsk_ino = le16_to_cpu(di->i_ino);
-	inode->i_uid =  le32_to_cpu(di->i_uid);
-	inode->i_gid =  le32_to_cpu(di->i_gid);
-	inode->i_nlink =  le32_to_cpu(di->i_nlink);
+	i_uid_write(inode, le32_to_cpu(di->i_uid));
+	i_gid_write(inode,  le32_to_cpu(di->i_gid));
+	set_nlink(inode, le32_to_cpu(di->i_nlink));
 	inode->i_size = BFS_FILESIZE(di);
 	inode->i_blocks = BFS_FILEBLOCKS(di);
 	inode->i_atime.tv_sec =  le32_to_cpu(di->i_atime);
@@ -97,33 +97,40 @@ error:
 	return ERR_PTR(-EIO);
 }
 
-static int bfs_write_inode(struct inode *inode, int unused)
+static struct bfs_inode *find_inode(struct super_block *sb, u16 ino, struct buffer_head **p)
 {
+	if ((ino < BFS_ROOT_INO) || (ino > BFS_SB(sb)->si_lasti)) {
+		printf("Bad inode number %s:%08x\n", sb->s_id, ino);
+		return ERR_PTR(-EIO);
+	}
+
+	ino -= BFS_ROOT_INO;
+
+	*p = sb_bread(sb, 1 + ino / BFS_INODES_PER_BLOCK);
+	if (!*p) {
+		printf("Unable to read inode %s:%08x\n", sb->s_id, ino);
+		return ERR_PTR(-EIO);
+	}
+
+	return (struct bfs_inode *)(*p)->b_data +  ino % BFS_INODES_PER_BLOCK;
+}
+
+static int bfs_write_inode(struct inode *inode, struct writeback_control *wbc)
+{
+	struct bfs_sb_info *info = BFS_SB(inode->i_sb);
 	unsigned int ino = (u16)inode->i_ino;
         unsigned long i_sblock;
 	struct bfs_inode *di;
 	struct buffer_head *bh;
-	int block, off;
+	int err = 0;
 
         dprintf("ino=%08x\n", ino);
 
-	if ((ino < BFS_ROOT_INO) || (ino > BFS_SB(inode->i_sb)->si_lasti)) {
-		printf("Bad inode number %s:%08x\n", inode->i_sb->s_id, ino);
-		return -EIO;
-	}
+	di = find_inode(inode->i_sb, ino, &bh);
+	if (IS_ERR(di))
+		return PTR_ERR(di);
 
-	lock_kernel();
-	block = (ino - BFS_ROOT_INO) / BFS_INODES_PER_BLOCK + 1;
-	bh = sb_bread(inode->i_sb, block);
-	if (!bh) {
-		printf("Unable to read inode %s:%08x\n",
-				inode->i_sb->s_id, ino);
-		unlock_kernel();
-		return -EIO;
-	}
-
-	off = (ino - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK;
-	di = (struct bfs_inode *)bh->b_data + off;
+	mutex_lock(&info->bfs_lock);
 
 	if (ino == BFS_ROOT_INO)
 		di->i_vtype = cpu_to_le32(BFS_VDIR);
@@ -132,8 +139,8 @@ static int bfs_write_inode(struct inode *inode, int unused)
 
 	di->i_ino = cpu_to_le16(ino);
 	di->i_mode = cpu_to_le32(inode->i_mode);
-	di->i_uid = cpu_to_le32(inode->i_uid);
-	di->i_gid = cpu_to_le32(inode->i_gid);
+	di->i_uid = cpu_to_le32(i_uid_read(inode));
+	di->i_gid = cpu_to_le32(i_gid_read(inode));
 	di->i_nlink = cpu_to_le32(inode->i_nlink);
 	di->i_atime = cpu_to_le32(inode->i_atime.tv_sec);
 	di->i_mtime = cpu_to_le32(inode->i_mtime.tv_sec);
@@ -144,46 +151,41 @@ static int bfs_write_inode(struct inode *inode, int unused)
 	di->i_eoffset = cpu_to_le32(i_sblock * BFS_BSIZE + inode->i_size - 1);
 
 	mark_buffer_dirty(bh);
+	if (wbc->sync_mode == WB_SYNC_ALL) {
+		sync_dirty_buffer(bh);
+		if (buffer_req(bh) && !buffer_uptodate(bh))
+			err = -EIO;
+	}
 	brelse(bh);
-	unlock_kernel();
-	return 0;
+	mutex_unlock(&info->bfs_lock);
+	return err;
 }
 
-static void bfs_delete_inode(struct inode *inode)
+static void bfs_evict_inode(struct inode *inode)
 {
 	unsigned long ino = inode->i_ino;
 	struct bfs_inode *di;
 	struct buffer_head *bh;
-	int block, off;
 	struct super_block *s = inode->i_sb;
 	struct bfs_sb_info *info = BFS_SB(s);
 	struct bfs_inode_info *bi = BFS_I(inode);
 
 	dprintf("ino=%08lx\n", ino);
 
-	truncate_inode_pages(&inode->i_data, 0);
+	truncate_inode_pages_final(&inode->i_data);
+	invalidate_inode_buffers(inode);
+	clear_inode(inode);
 
-	if ((ino < BFS_ROOT_INO) || (ino > info->si_lasti)) {
-		printf("invalid ino=%08lx\n", ino);
+	if (inode->i_nlink)
 		return;
-	}
-	
-	inode->i_size = 0;
-	inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME_SEC;
-	lock_kernel();
-	mark_inode_dirty(inode);
 
-	block = (ino - BFS_ROOT_INO) / BFS_INODES_PER_BLOCK + 1;
-	bh = sb_bread(s, block);
-	if (!bh) {
-		printf("Unable to read inode %s:%08lx\n",
-					inode->i_sb->s_id, ino);
-		unlock_kernel();
+	di = find_inode(s, inode->i_ino, &bh);
+	if (IS_ERR(di))
 		return;
-	}
-	off = (ino - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK;
-	di = (struct bfs_inode *)bh->b_data + off;
-	memset((void *)di, 0, sizeof(struct bfs_inode));
+
+	mutex_lock(&info->bfs_lock);
+	/* clear on-disk inode */
+	memset(di, 0, sizeof(struct bfs_inode));
 	mark_buffer_dirty(bh);
 	brelse(bh);
 
@@ -200,18 +202,19 @@ static void bfs_delete_inode(struct inode *inode)
 	 * "last block of the last file" even if there is no
 	 * real file there, saves us 1 gap.
 	 */
-	if (info->si_lf_eblk == bi->i_eblock) {
+	if (info->si_lf_eblk == bi->i_eblock)
 		info->si_lf_eblk = bi->i_sblock - 1;
-		mark_buffer_dirty(info->si_sbh);
-	}
-	unlock_kernel();
-	clear_inode(inode);
+	mutex_unlock(&info->bfs_lock);
 }
 
 static void bfs_put_super(struct super_block *s)
 {
 	struct bfs_sb_info *info = BFS_SB(s);
-	brelse(info->si_sbh);
+
+	if (!info)
+		return;
+
+	mutex_destroy(&info->bfs_lock);
 	kfree(info->si_imap);
 	kfree(info);
 	s->s_fs_info = NULL;
@@ -234,15 +237,6 @@ static int bfs_statfs(struct dentry *dentry, struct kstatfs *buf)
 	return 0;
 }
 
-static void bfs_write_super(struct super_block *s)
-{
-	lock_kernel();
-	if (!(s->s_flags & MS_RDONLY))
-		mark_buffer_dirty(BFS_SB(s)->si_sbh);
-	s->s_dirt = 0;
-	unlock_kernel();
-}
-
 static struct kmem_cache *bfs_inode_cachep;
 
 static struct inode *bfs_alloc_inode(struct super_block *sb)
@@ -254,19 +248,25 @@ static struct inode *bfs_alloc_inode(struct super_block *sb)
 	return &bi->vfs_inode;
 }
 
-static void bfs_destroy_inode(struct inode *inode)
+static void bfs_i_callback(struct rcu_head *head)
 {
+	struct inode *inode = container_of(head, struct inode, i_rcu);
 	kmem_cache_free(bfs_inode_cachep, BFS_I(inode));
 }
 
-static void init_once(struct kmem_cache *cachep, void *foo)
+static void bfs_destroy_inode(struct inode *inode)
+{
+	call_rcu(&inode->i_rcu, bfs_i_callback);
+}
+
+static void init_once(void *foo)
 {
 	struct bfs_inode_info *bi = foo;
 
 	inode_init_once(&bi->vfs_inode);
 }
 
-static int init_inodecache(void)
+static int __init init_inodecache(void)
 {
 	bfs_inode_cachep = kmem_cache_create("bfs_inode_cache",
 					     sizeof(struct bfs_inode_info),
@@ -280,6 +280,11 @@ static int init_inodecache(void)
 
 static void destroy_inodecache(void)
 {
+	/*
+	 * Make sure all delayed rcu free inodes are flushed before we
+	 * destroy cache.
+	 */
+	rcu_barrier();
 	kmem_cache_destroy(bfs_inode_cachep);
 }
 
@@ -287,9 +292,8 @@ static const struct super_operations bfs_sops = {
 	.alloc_inode	= bfs_alloc_inode,
 	.destroy_inode	= bfs_destroy_inode,
 	.write_inode	= bfs_write_inode,
-	.delete_inode	= bfs_delete_inode,
+	.evict_inode	= bfs_evict_inode,
 	.put_super	= bfs_put_super,
-	.write_super	= bfs_write_super,
 	.statfs		= bfs_statfs,
 };
 
@@ -316,42 +320,49 @@ void dump_imap(const char *prefix, struct super_block *s)
 
 static int bfs_fill_super(struct super_block *s, void *data, int silent)
 {
-	struct buffer_head *bh;
+	struct buffer_head *bh, *sbh;
 	struct bfs_super_block *bfs_sb;
 	struct inode *inode;
 	unsigned i, imap_len;
 	struct bfs_sb_info *info;
-	long ret = -EINVAL;
+	int ret = -EINVAL;
+	unsigned long i_sblock, i_eblock, i_eoff, s_size;
 
 	info = kzalloc(sizeof(*info), GFP_KERNEL);
 	if (!info)
 		return -ENOMEM;
+	mutex_init(&info->bfs_lock);
 	s->s_fs_info = info;
 
 	sb_set_blocksize(s, BFS_BSIZE);
 
-	bh = sb_bread(s, 0);
-	if(!bh)
+	sbh = sb_bread(s, 0);
+	if (!sbh)
 		goto out;
-	bfs_sb = (struct bfs_super_block *)bh->b_data;
+	bfs_sb = (struct bfs_super_block *)sbh->b_data;
 	if (le32_to_cpu(bfs_sb->s_magic) != BFS_MAGIC) {
 		if (!silent)
 			printf("No BFS filesystem on %s (magic=%08x)\n", 
 				s->s_id,  le32_to_cpu(bfs_sb->s_magic));
-		goto out;
+		goto out1;
 	}
 	if (BFS_UNCLEAN(bfs_sb, s) && !silent)
 		printf("%s is unclean, continuing\n", s->s_id);
 
 	s->s_magic = BFS_MAGIC;
-	info->si_sbh = bh;
+
+	if (le32_to_cpu(bfs_sb->s_start) > le32_to_cpu(bfs_sb->s_end)) {
+		printf("Superblock is corrupted\n");
+		goto out1;
+	}
+
 	info->si_lasti = (le32_to_cpu(bfs_sb->s_start) - BFS_BSIZE) /
 					sizeof(struct bfs_inode)
 					+ BFS_ROOT_INO - 1;
 	imap_len = (info->si_lasti / 8) + 1;
 	info->si_imap = kzalloc(imap_len, GFP_KERNEL);
 	if (!info->si_imap)
-		goto out;
+		goto out1;
 	for (i = 0; i < BFS_ROOT_INO; i++)
 		set_bit(i, info->si_imap);
 
@@ -359,15 +370,12 @@ static int bfs_fill_super(struct super_block *s, void *data, int silent)
 	inode = bfs_iget(s, BFS_ROOT_INO);
 	if (IS_ERR(inode)) {
 		ret = PTR_ERR(inode);
-		kfree(info->si_imap);
-		goto out;
+		goto out2;
 	}
-	s->s_root = d_alloc_root(inode);
+	s->s_root = d_make_root(inode);
 	if (!s->s_root) {
-		iput(inode);
 		ret = -ENOMEM;
-		kfree(info->si_imap);
-		goto out;
+		goto out2;
 	}
 
 	info->si_blocks = (le32_to_cpu(bfs_sb->s_end) + 1) >> BFS_BSIZE_BITS;
@@ -375,12 +383,22 @@ static int bfs_fill_super(struct super_block *s, void *data, int silent)
 			- le32_to_cpu(bfs_sb->s_start)) >> BFS_BSIZE_BITS;
 	info->si_freei = 0;
 	info->si_lf_eblk = 0;
+
+	/* can we read the last block? */
+	bh = sb_bread(s, info->si_blocks - 1);
+	if (!bh) {
+		printf("Last block not available: %lu\n", info->si_blocks - 1);
+		ret = -EIO;
+		goto out3;
+	}
+	brelse(bh);
+
 	bh = NULL;
 	for (i = BFS_ROOT_INO; i <= info->si_lasti; i++) {
 		struct bfs_inode *di;
 		int block = (i - BFS_ROOT_INO) / BFS_INODES_PER_BLOCK + 1;
 		int off = (i - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK;
-		unsigned long sblock, eblock;
+		unsigned long eblock;
 
 		if (!off) {
 			brelse(bh);
@@ -392,6 +410,26 @@ static int bfs_fill_super(struct super_block *s, void *data, int silent)
 
 		di = (struct bfs_inode *)bh->b_data + off;
 
+		/* test if filesystem is not corrupted */
+
+		i_eoff = le32_to_cpu(di->i_eoffset);
+		i_sblock = le32_to_cpu(di->i_sblock);
+		i_eblock = le32_to_cpu(di->i_eblock);
+		s_size = le32_to_cpu(bfs_sb->s_end);
+
+		if (i_sblock > info->si_blocks ||
+			i_eblock > info->si_blocks ||
+			i_sblock > i_eblock ||
+			i_eoff > s_size ||
+			i_sblock * BFS_BSIZE > i_eoff) {
+
+			printf("Inode 0x%08x corrupted\n", i);
+
+			brelse(bh);
+			ret = -EIO;
+			goto out3;
+		}
+
 		if (!di->i_ino) {
 			info->si_freei++;
 			continue;
@@ -399,39 +437,43 @@ static int bfs_fill_super(struct super_block *s, void *data, int silent)
 		set_bit(i, info->si_imap);
 		info->si_freeb -= BFS_FILEBLOCKS(di);
 
-		sblock =  le32_to_cpu(di->i_sblock);
 		eblock =  le32_to_cpu(di->i_eblock);
 		if (eblock > info->si_lf_eblk)
 			info->si_lf_eblk = eblock;
 	}
 	brelse(bh);
-	if (!(s->s_flags & MS_RDONLY)) {
-		mark_buffer_dirty(info->si_sbh);
-		s->s_dirt = 1;
-	} 
+	brelse(sbh);
 	dump_imap("read_super", s);
 	return 0;
 
+out3:
+	dput(s->s_root);
+	s->s_root = NULL;
+out2:
+	kfree(info->si_imap);
+out1:
+	brelse(sbh);
 out:
-	brelse(bh);
+	mutex_destroy(&info->bfs_lock);
 	kfree(info);
 	s->s_fs_info = NULL;
 	return ret;
 }
 
-static int bfs_get_sb(struct file_system_type *fs_type,
-	int flags, const char *dev_name, void *data, struct vfsmount *mnt)
+static struct dentry *bfs_mount(struct file_system_type *fs_type,
+	int flags, const char *dev_name, void *data)
 {
-	return get_sb_bdev(fs_type, flags, dev_name, data, bfs_fill_super, mnt);
+	return mount_bdev(fs_type, flags, dev_name, data, bfs_fill_super);
 }
 
 static struct file_system_type bfs_fs_type = {
 	.owner		= THIS_MODULE,
 	.name		= "bfs",
-	.get_sb		= bfs_get_sb,
+	.mount		= bfs_mount,
 	.kill_sb	= kill_block_super,
 	.fs_flags	= FS_REQUIRES_DEV,
 };
+MODULE_ALIAS_FS("bfs");
 
 static int __init init_bfs_fs(void)
 {