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-rw-r--r--fs/bfs/Kconfig20
-rw-r--r--fs/bfs/Makefile8
-rw-r--r--fs/bfs/bfs.h68
-rw-r--r--fs/bfs/dir.c359
-rw-r--r--fs/bfs/file.c198
-rw-r--r--fs/bfs/inode.c489
6 files changed, 1142 insertions, 0 deletions
diff --git a/fs/bfs/Kconfig b/fs/bfs/Kconfig
new file mode 100644
index 000000000..3a757805b
--- /dev/null
+++ b/fs/bfs/Kconfig
@@ -0,0 +1,20 @@
+# SPDX-License-Identifier: GPL-2.0-only
+config BFS_FS
+ tristate "BFS file system support"
+ depends on BLOCK
+ help
+ Boot File System (BFS) is a file system used under SCO UnixWare to
+ allow the bootloader access to the kernel image and other important
+ files during the boot process. It is usually mounted under /stand
+ and corresponds to the slice marked as "STAND" in the UnixWare
+ partition. You should say Y if you want to read or write the files
+ on your /stand slice from within Linux. You then also need to say Y
+ to "UnixWare slices support", below. More information about the BFS
+ file system is contained in the file
+ <file:Documentation/filesystems/bfs.rst>.
+
+ If you don't know what this is about, say N.
+
+ To compile this as a module, choose M here: the module will be called
+ bfs. Note that the file system of your root partition (the one
+ containing the directory /) cannot be compiled as a module.
diff --git a/fs/bfs/Makefile b/fs/bfs/Makefile
new file mode 100644
index 000000000..2b6bc5eb4
--- /dev/null
+++ b/fs/bfs/Makefile
@@ -0,0 +1,8 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# Makefile for BFS filesystem.
+#
+
+obj-$(CONFIG_BFS_FS) += bfs.o
+
+bfs-objs := inode.o file.o dir.o
diff --git a/fs/bfs/bfs.h b/fs/bfs/bfs.h
new file mode 100644
index 000000000..606f9378b
--- /dev/null
+++ b/fs/bfs/bfs.h
@@ -0,0 +1,68 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * fs/bfs/bfs.h
+ * Copyright (C) 1999-2018 Tigran Aivazian <aivazian.tigran@gmail.com>
+ */
+#ifndef _FS_BFS_BFS_H
+#define _FS_BFS_BFS_H
+
+#include <linux/bfs_fs.h>
+
+/* In theory BFS supports up to 512 inodes, numbered from 2 (for /) up to 513 inclusive.
+ In actual fact, attempting to create the 512th inode (i.e. inode No. 513 or file No. 511)
+ will fail with ENOSPC in bfs_add_entry(): the root directory cannot contain so many entries, counting '..'.
+ So, mkfs.bfs(8) should really limit its -N option to 511 and not 512. For now, we just print a warning
+ if a filesystem is mounted with such "impossible to fill up" number of inodes */
+#define BFS_MAX_LASTI 513
+
+/*
+ * BFS file system in-core superblock info
+ */
+struct bfs_sb_info {
+ unsigned long si_blocks;
+ unsigned long si_freeb;
+ unsigned long si_freei;
+ unsigned long si_lf_eblk;
+ unsigned long si_lasti;
+ DECLARE_BITMAP(si_imap, BFS_MAX_LASTI+1);
+ struct mutex bfs_lock;
+};
+
+/*
+ * BFS file system in-core inode info
+ */
+struct bfs_inode_info {
+ unsigned long i_dsk_ino; /* inode number from the disk, can be 0 */
+ unsigned long i_sblock;
+ unsigned long i_eblock;
+ struct inode vfs_inode;
+};
+
+static inline struct bfs_sb_info *BFS_SB(struct super_block *sb)
+{
+ return sb->s_fs_info;
+}
+
+static inline struct bfs_inode_info *BFS_I(struct inode *inode)
+{
+ return container_of(inode, struct bfs_inode_info, vfs_inode);
+}
+
+
+#define printf(format, args...) \
+ printk(KERN_ERR "BFS-fs: %s(): " format, __func__, ## args)
+
+/* inode.c */
+extern struct inode *bfs_iget(struct super_block *sb, unsigned long ino);
+extern void bfs_dump_imap(const char *, struct super_block *);
+
+/* file.c */
+extern const struct inode_operations bfs_file_inops;
+extern const struct file_operations bfs_file_operations;
+extern const struct address_space_operations bfs_aops;
+
+/* dir.c */
+extern const struct inode_operations bfs_dir_inops;
+extern const struct file_operations bfs_dir_operations;
+
+#endif /* _FS_BFS_BFS_H */
diff --git a/fs/bfs/dir.c b/fs/bfs/dir.c
new file mode 100644
index 000000000..d8dfe3a0c
--- /dev/null
+++ b/fs/bfs/dir.c
@@ -0,0 +1,359 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * fs/bfs/dir.c
+ * BFS directory operations.
+ * Copyright (C) 1999-2018 Tigran Aivazian <aivazian.tigran@gmail.com>
+ * Made endianness-clean by Andrew Stribblehill <ads@wompom.org> 2005
+ */
+
+#include <linux/time.h>
+#include <linux/string.h>
+#include <linux/fs.h>
+#include <linux/buffer_head.h>
+#include <linux/sched.h>
+#include "bfs.h"
+
+#undef DEBUG
+
+#ifdef DEBUG
+#define dprintf(x...) printf(x)
+#else
+#define dprintf(x...)
+#endif
+
+static int bfs_add_entry(struct inode *dir, const struct qstr *child, int ino);
+static struct buffer_head *bfs_find_entry(struct inode *dir,
+ const struct qstr *child,
+ struct bfs_dirent **res_dir);
+
+static int bfs_readdir(struct file *f, struct dir_context *ctx)
+{
+ struct inode *dir = file_inode(f);
+ struct buffer_head *bh;
+ struct bfs_dirent *de;
+ unsigned int offset;
+ int block;
+
+ if (ctx->pos & (BFS_DIRENT_SIZE - 1)) {
+ printf("Bad f_pos=%08lx for %s:%08lx\n",
+ (unsigned long)ctx->pos,
+ dir->i_sb->s_id, dir->i_ino);
+ return -EINVAL;
+ }
+
+ while (ctx->pos < dir->i_size) {
+ offset = ctx->pos & (BFS_BSIZE - 1);
+ block = BFS_I(dir)->i_sblock + (ctx->pos >> BFS_BSIZE_BITS);
+ bh = sb_bread(dir->i_sb, block);
+ if (!bh) {
+ ctx->pos += BFS_BSIZE - offset;
+ continue;
+ }
+ do {
+ de = (struct bfs_dirent *)(bh->b_data + offset);
+ if (de->ino) {
+ int size = strnlen(de->name, BFS_NAMELEN);
+ if (!dir_emit(ctx, de->name, size,
+ le16_to_cpu(de->ino),
+ DT_UNKNOWN)) {
+ brelse(bh);
+ return 0;
+ }
+ }
+ offset += BFS_DIRENT_SIZE;
+ ctx->pos += BFS_DIRENT_SIZE;
+ } while ((offset < BFS_BSIZE) && (ctx->pos < dir->i_size));
+ brelse(bh);
+ }
+ return 0;
+}
+
+const struct file_operations bfs_dir_operations = {
+ .read = generic_read_dir,
+ .iterate_shared = bfs_readdir,
+ .fsync = generic_file_fsync,
+ .llseek = generic_file_llseek,
+};
+
+static int bfs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
+ bool excl)
+{
+ int err;
+ struct inode *inode;
+ struct super_block *s = dir->i_sb;
+ struct bfs_sb_info *info = BFS_SB(s);
+ unsigned long ino;
+
+ inode = new_inode(s);
+ if (!inode)
+ return -ENOMEM;
+ mutex_lock(&info->bfs_lock);
+ ino = find_first_zero_bit(info->si_imap, info->si_lasti + 1);
+ if (ino > info->si_lasti) {
+ mutex_unlock(&info->bfs_lock);
+ iput(inode);
+ return -ENOSPC;
+ }
+ set_bit(ino, info->si_imap);
+ info->si_freei--;
+ inode_init_owner(inode, dir, mode);
+ inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode);
+ inode->i_blocks = 0;
+ inode->i_op = &bfs_file_inops;
+ inode->i_fop = &bfs_file_operations;
+ inode->i_mapping->a_ops = &bfs_aops;
+ inode->i_ino = ino;
+ BFS_I(inode)->i_dsk_ino = ino;
+ BFS_I(inode)->i_sblock = 0;
+ BFS_I(inode)->i_eblock = 0;
+ insert_inode_hash(inode);
+ mark_inode_dirty(inode);
+ bfs_dump_imap("create", s);
+
+ err = bfs_add_entry(dir, &dentry->d_name, inode->i_ino);
+ if (err) {
+ inode_dec_link_count(inode);
+ mutex_unlock(&info->bfs_lock);
+ iput(inode);
+ return err;
+ }
+ mutex_unlock(&info->bfs_lock);
+ d_instantiate(dentry, inode);
+ return 0;
+}
+
+static struct dentry *bfs_lookup(struct inode *dir, struct dentry *dentry,
+ unsigned int flags)
+{
+ struct inode *inode = NULL;
+ struct buffer_head *bh;
+ struct bfs_dirent *de;
+ struct bfs_sb_info *info = BFS_SB(dir->i_sb);
+
+ if (dentry->d_name.len > BFS_NAMELEN)
+ return ERR_PTR(-ENAMETOOLONG);
+
+ mutex_lock(&info->bfs_lock);
+ bh = bfs_find_entry(dir, &dentry->d_name, &de);
+ if (bh) {
+ unsigned long ino = (unsigned long)le16_to_cpu(de->ino);
+ brelse(bh);
+ inode = bfs_iget(dir->i_sb, ino);
+ }
+ mutex_unlock(&info->bfs_lock);
+ return d_splice_alias(inode, dentry);
+}
+
+static int bfs_link(struct dentry *old, struct inode *dir,
+ struct dentry *new)
+{
+ struct inode *inode = d_inode(old);
+ struct bfs_sb_info *info = BFS_SB(inode->i_sb);
+ int err;
+
+ mutex_lock(&info->bfs_lock);
+ err = bfs_add_entry(dir, &new->d_name, inode->i_ino);
+ if (err) {
+ mutex_unlock(&info->bfs_lock);
+ return err;
+ }
+ inc_nlink(inode);
+ inode->i_ctime = current_time(inode);
+ mark_inode_dirty(inode);
+ ihold(inode);
+ d_instantiate(new, inode);
+ mutex_unlock(&info->bfs_lock);
+ return 0;
+}
+
+static int bfs_unlink(struct inode *dir, struct dentry *dentry)
+{
+ int error = -ENOENT;
+ struct inode *inode = d_inode(dentry);
+ struct buffer_head *bh;
+ struct bfs_dirent *de;
+ struct bfs_sb_info *info = BFS_SB(inode->i_sb);
+
+ mutex_lock(&info->bfs_lock);
+ bh = bfs_find_entry(dir, &dentry->d_name, &de);
+ if (!bh || (le16_to_cpu(de->ino) != inode->i_ino))
+ goto out_brelse;
+
+ if (!inode->i_nlink) {
+ printf("unlinking non-existent file %s:%lu (nlink=%d)\n",
+ inode->i_sb->s_id, inode->i_ino,
+ inode->i_nlink);
+ set_nlink(inode, 1);
+ }
+ de->ino = 0;
+ mark_buffer_dirty_inode(bh, dir);
+ dir->i_ctime = dir->i_mtime = current_time(dir);
+ mark_inode_dirty(dir);
+ inode->i_ctime = dir->i_ctime;
+ inode_dec_link_count(inode);
+ error = 0;
+
+out_brelse:
+ brelse(bh);
+ mutex_unlock(&info->bfs_lock);
+ return error;
+}
+
+static int bfs_rename(struct inode *old_dir, struct dentry *old_dentry,
+ struct inode *new_dir, struct dentry *new_dentry,
+ unsigned int flags)
+{
+ struct inode *old_inode, *new_inode;
+ struct buffer_head *old_bh, *new_bh;
+ struct bfs_dirent *old_de, *new_de;
+ struct bfs_sb_info *info;
+ int error = -ENOENT;
+
+ if (flags & ~RENAME_NOREPLACE)
+ return -EINVAL;
+
+ old_bh = new_bh = NULL;
+ old_inode = d_inode(old_dentry);
+ if (S_ISDIR(old_inode->i_mode))
+ return -EINVAL;
+
+ info = BFS_SB(old_inode->i_sb);
+
+ mutex_lock(&info->bfs_lock);
+ old_bh = bfs_find_entry(old_dir, &old_dentry->d_name, &old_de);
+
+ if (!old_bh || (le16_to_cpu(old_de->ino) != old_inode->i_ino))
+ goto end_rename;
+
+ error = -EPERM;
+ new_inode = d_inode(new_dentry);
+ new_bh = bfs_find_entry(new_dir, &new_dentry->d_name, &new_de);
+
+ if (new_bh && !new_inode) {
+ brelse(new_bh);
+ new_bh = NULL;
+ }
+ if (!new_bh) {
+ error = bfs_add_entry(new_dir, &new_dentry->d_name,
+ old_inode->i_ino);
+ if (error)
+ goto end_rename;
+ }
+ old_de->ino = 0;
+ old_dir->i_ctime = old_dir->i_mtime = current_time(old_dir);
+ mark_inode_dirty(old_dir);
+ if (new_inode) {
+ new_inode->i_ctime = current_time(new_inode);
+ inode_dec_link_count(new_inode);
+ }
+ mark_buffer_dirty_inode(old_bh, old_dir);
+ error = 0;
+
+end_rename:
+ mutex_unlock(&info->bfs_lock);
+ brelse(old_bh);
+ brelse(new_bh);
+ return error;
+}
+
+const struct inode_operations bfs_dir_inops = {
+ .create = bfs_create,
+ .lookup = bfs_lookup,
+ .link = bfs_link,
+ .unlink = bfs_unlink,
+ .rename = bfs_rename,
+};
+
+static int bfs_add_entry(struct inode *dir, const struct qstr *child, int ino)
+{
+ const unsigned char *name = child->name;
+ int namelen = child->len;
+ struct buffer_head *bh;
+ struct bfs_dirent *de;
+ int block, sblock, eblock, off, pos;
+ int i;
+
+ dprintf("name=%s, namelen=%d\n", name, namelen);
+
+ if (!namelen)
+ return -ENOENT;
+ if (namelen > BFS_NAMELEN)
+ return -ENAMETOOLONG;
+
+ sblock = BFS_I(dir)->i_sblock;
+ eblock = BFS_I(dir)->i_eblock;
+ for (block = sblock; block <= eblock; block++) {
+ bh = sb_bread(dir->i_sb, block);
+ if (!bh)
+ return -EIO;
+ for (off = 0; off < BFS_BSIZE; off += BFS_DIRENT_SIZE) {
+ de = (struct bfs_dirent *)(bh->b_data + off);
+ if (!de->ino) {
+ pos = (block - sblock) * BFS_BSIZE + off;
+ if (pos >= dir->i_size) {
+ dir->i_size += BFS_DIRENT_SIZE;
+ dir->i_ctime = current_time(dir);
+ }
+ dir->i_mtime = current_time(dir);
+ mark_inode_dirty(dir);
+ de->ino = cpu_to_le16((u16)ino);
+ for (i = 0; i < BFS_NAMELEN; i++)
+ de->name[i] =
+ (i < namelen) ? name[i] : 0;
+ mark_buffer_dirty_inode(bh, dir);
+ brelse(bh);
+ return 0;
+ }
+ }
+ brelse(bh);
+ }
+ return -ENOSPC;
+}
+
+static inline int bfs_namecmp(int len, const unsigned char *name,
+ const char *buffer)
+{
+ if ((len < BFS_NAMELEN) && buffer[len])
+ return 0;
+ return !memcmp(name, buffer, len);
+}
+
+static struct buffer_head *bfs_find_entry(struct inode *dir,
+ const struct qstr *child,
+ struct bfs_dirent **res_dir)
+{
+ unsigned long block = 0, offset = 0;
+ struct buffer_head *bh = NULL;
+ struct bfs_dirent *de;
+ const unsigned char *name = child->name;
+ int namelen = child->len;
+
+ *res_dir = NULL;
+ if (namelen > BFS_NAMELEN)
+ return NULL;
+
+ while (block * BFS_BSIZE + offset < dir->i_size) {
+ if (!bh) {
+ bh = sb_bread(dir->i_sb, BFS_I(dir)->i_sblock + block);
+ if (!bh) {
+ block++;
+ continue;
+ }
+ }
+ de = (struct bfs_dirent *)(bh->b_data + offset);
+ offset += BFS_DIRENT_SIZE;
+ if (le16_to_cpu(de->ino) &&
+ bfs_namecmp(namelen, name, de->name)) {
+ *res_dir = de;
+ return bh;
+ }
+ if (offset < bh->b_size)
+ continue;
+ brelse(bh);
+ bh = NULL;
+ offset = 0;
+ block++;
+ }
+ brelse(bh);
+ return NULL;
+}
diff --git a/fs/bfs/file.c b/fs/bfs/file.c
new file mode 100644
index 000000000..0dceefc54
--- /dev/null
+++ b/fs/bfs/file.c
@@ -0,0 +1,198 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * fs/bfs/file.c
+ * BFS file operations.
+ * Copyright (C) 1999-2018 Tigran Aivazian <aivazian.tigran@gmail.com>
+ *
+ * Make the file block allocation algorithm understand the size
+ * of the underlying block device.
+ * Copyright (C) 2007 Dmitri Vorobiev <dmitri.vorobiev@gmail.com>
+ *
+ */
+
+#include <linux/fs.h>
+#include <linux/buffer_head.h>
+#include "bfs.h"
+
+#undef DEBUG
+
+#ifdef DEBUG
+#define dprintf(x...) printf(x)
+#else
+#define dprintf(x...)
+#endif
+
+const struct file_operations bfs_file_operations = {
+ .llseek = generic_file_llseek,
+ .read_iter = generic_file_read_iter,
+ .write_iter = generic_file_write_iter,
+ .mmap = generic_file_mmap,
+ .splice_read = generic_file_splice_read,
+};
+
+static int bfs_move_block(unsigned long from, unsigned long to,
+ struct super_block *sb)
+{
+ struct buffer_head *bh, *new;
+
+ bh = sb_bread(sb, from);
+ if (!bh)
+ return -EIO;
+ new = sb_getblk(sb, to);
+ memcpy(new->b_data, bh->b_data, bh->b_size);
+ mark_buffer_dirty(new);
+ bforget(bh);
+ brelse(new);
+ return 0;
+}
+
+static int bfs_move_blocks(struct super_block *sb, unsigned long start,
+ unsigned long end, unsigned long where)
+{
+ unsigned long i;
+
+ dprintf("%08lx-%08lx->%08lx\n", start, end, where);
+ for (i = start; i <= end; i++)
+ if(bfs_move_block(i, where + i, sb)) {
+ dprintf("failed to move block %08lx -> %08lx\n", i,
+ where + i);
+ return -EIO;
+ }
+ return 0;
+}
+
+static int bfs_get_block(struct inode *inode, sector_t block,
+ struct buffer_head *bh_result, int create)
+{
+ unsigned long phys;
+ int err;
+ struct super_block *sb = inode->i_sb;
+ struct bfs_sb_info *info = BFS_SB(sb);
+ struct bfs_inode_info *bi = BFS_I(inode);
+
+ phys = bi->i_sblock + block;
+ if (!create) {
+ if (phys <= bi->i_eblock) {
+ dprintf("c=%d, b=%08lx, phys=%09lx (granted)\n",
+ create, (unsigned long)block, phys);
+ map_bh(bh_result, sb, phys);
+ }
+ return 0;
+ }
+
+ /*
+ * If the file is not empty and the requested block is within the
+ * range of blocks allocated for this file, we can grant it.
+ */
+ if (bi->i_sblock && (phys <= bi->i_eblock)) {
+ dprintf("c=%d, b=%08lx, phys=%08lx (interim block granted)\n",
+ create, (unsigned long)block, phys);
+ map_bh(bh_result, sb, phys);
+ return 0;
+ }
+
+ /* The file will be extended, so let's see if there is enough space. */
+ if (phys >= info->si_blocks)
+ return -ENOSPC;
+
+ /* The rest has to be protected against itself. */
+ mutex_lock(&info->bfs_lock);
+
+ /*
+ * If the last data block for this file is the last allocated
+ * block, we can extend the file trivially, without moving it
+ * anywhere.
+ */
+ if (bi->i_eblock == info->si_lf_eblk) {
+ dprintf("c=%d, b=%08lx, phys=%08lx (simple extension)\n",
+ create, (unsigned long)block, phys);
+ map_bh(bh_result, sb, phys);
+ info->si_freeb -= phys - bi->i_eblock;
+ info->si_lf_eblk = bi->i_eblock = phys;
+ mark_inode_dirty(inode);
+ err = 0;
+ goto out;
+ }
+
+ /* Ok, we have to move this entire file to the next free block. */
+ phys = info->si_lf_eblk + 1;
+ if (phys + block >= info->si_blocks) {
+ err = -ENOSPC;
+ goto out;
+ }
+
+ if (bi->i_sblock) {
+ err = bfs_move_blocks(inode->i_sb, bi->i_sblock,
+ bi->i_eblock, phys);
+ if (err) {
+ dprintf("failed to move ino=%08lx -> fs corruption\n",
+ inode->i_ino);
+ goto out;
+ }
+ } else
+ err = 0;
+
+ dprintf("c=%d, b=%08lx, phys=%08lx (moved)\n",
+ create, (unsigned long)block, phys);
+ bi->i_sblock = phys;
+ phys += block;
+ info->si_lf_eblk = bi->i_eblock = phys;
+
+ /*
+ * This assumes nothing can write the inode back while we are here
+ * and thus update inode->i_blocks! (XXX)
+ */
+ info->si_freeb -= bi->i_eblock - bi->i_sblock + 1 - inode->i_blocks;
+ mark_inode_dirty(inode);
+ map_bh(bh_result, sb, phys);
+out:
+ mutex_unlock(&info->bfs_lock);
+ return err;
+}
+
+static int bfs_writepage(struct page *page, struct writeback_control *wbc)
+{
+ return block_write_full_page(page, bfs_get_block, wbc);
+}
+
+static int bfs_readpage(struct file *file, struct page *page)
+{
+ return block_read_full_page(page, bfs_get_block);
+}
+
+static void bfs_write_failed(struct address_space *mapping, loff_t to)
+{
+ struct inode *inode = mapping->host;
+
+ if (to > inode->i_size)
+ truncate_pagecache(inode, inode->i_size);
+}
+
+static int bfs_write_begin(struct file *file, struct address_space *mapping,
+ loff_t pos, unsigned len, unsigned flags,
+ struct page **pagep, void **fsdata)
+{
+ int ret;
+
+ ret = block_write_begin(mapping, pos, len, flags, pagep,
+ bfs_get_block);
+ if (unlikely(ret))
+ bfs_write_failed(mapping, pos + len);
+
+ return ret;
+}
+
+static sector_t bfs_bmap(struct address_space *mapping, sector_t block)
+{
+ return generic_block_bmap(mapping, block, bfs_get_block);
+}
+
+const struct address_space_operations bfs_aops = {
+ .readpage = bfs_readpage,
+ .writepage = bfs_writepage,
+ .write_begin = bfs_write_begin,
+ .write_end = generic_write_end,
+ .bmap = bfs_bmap,
+};
+
+const struct inode_operations bfs_file_inops;
diff --git a/fs/bfs/inode.c b/fs/bfs/inode.c
new file mode 100644
index 000000000..fd691e481
--- /dev/null
+++ b/fs/bfs/inode.c
@@ -0,0 +1,489 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * fs/bfs/inode.c
+ * BFS superblock and inode operations.
+ * Copyright (C) 1999-2018 Tigran Aivazian <aivazian.tigran@gmail.com>
+ * From fs/minix, Copyright (C) 1991, 1992 Linus Torvalds.
+ * Made endianness-clean by Andrew Stribblehill <ads@wompom.org>, 2005.
+ */
+
+#include <linux/module.h>
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <linux/init.h>
+#include <linux/fs.h>
+#include <linux/buffer_head.h>
+#include <linux/vfs.h>
+#include <linux/writeback.h>
+#include <linux/uio.h>
+#include <linux/uaccess.h>
+#include "bfs.h"
+
+MODULE_AUTHOR("Tigran Aivazian <aivazian.tigran@gmail.com>");
+MODULE_DESCRIPTION("SCO UnixWare BFS filesystem for Linux");
+MODULE_LICENSE("GPL");
+
+#undef DEBUG
+
+#ifdef DEBUG
+#define dprintf(x...) printf(x)
+#else
+#define dprintf(x...)
+#endif
+
+struct inode *bfs_iget(struct super_block *sb, unsigned long ino)
+{
+ struct bfs_inode *di;
+ struct inode *inode;
+ struct buffer_head *bh;
+ int block, off;
+
+ inode = iget_locked(sb, ino);
+ if (!inode)
+ return ERR_PTR(-ENOMEM);
+ if (!(inode->i_state & I_NEW))
+ return inode;
+
+ if ((ino < BFS_ROOT_INO) || (ino > BFS_SB(inode->i_sb)->si_lasti)) {
+ printf("Bad inode number %s:%08lx\n", inode->i_sb->s_id, ino);
+ goto error;
+ }
+
+ 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:%08lx\n", inode->i_sb->s_id,
+ ino);
+ goto error;
+ }
+
+ off = (ino - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK;
+ di = (struct bfs_inode *)bh->b_data + off;
+
+ inode->i_mode = 0x0000FFFF & le32_to_cpu(di->i_mode);
+ if (le32_to_cpu(di->i_vtype) == BFS_VDIR) {
+ inode->i_mode |= S_IFDIR;
+ inode->i_op = &bfs_dir_inops;
+ inode->i_fop = &bfs_dir_operations;
+ } else if (le32_to_cpu(di->i_vtype) == BFS_VREG) {
+ inode->i_mode |= S_IFREG;
+ inode->i_op = &bfs_file_inops;
+ inode->i_fop = &bfs_file_operations;
+ inode->i_mapping->a_ops = &bfs_aops;
+ }
+
+ 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);
+ 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);
+ inode->i_mtime.tv_sec = le32_to_cpu(di->i_mtime);
+ inode->i_ctime.tv_sec = le32_to_cpu(di->i_ctime);
+ inode->i_atime.tv_nsec = 0;
+ inode->i_mtime.tv_nsec = 0;
+ inode->i_ctime.tv_nsec = 0;
+
+ brelse(bh);
+ unlock_new_inode(inode);
+ return inode;
+
+error:
+ iget_failed(inode);
+ return ERR_PTR(-EIO);
+}
+
+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 err = 0;
+
+ dprintf("ino=%08x\n", ino);
+
+ di = find_inode(inode->i_sb, ino, &bh);
+ if (IS_ERR(di))
+ return PTR_ERR(di);
+
+ mutex_lock(&info->bfs_lock);
+
+ if (ino == BFS_ROOT_INO)
+ di->i_vtype = cpu_to_le32(BFS_VDIR);
+ else
+ di->i_vtype = cpu_to_le32(BFS_VREG);
+
+ di->i_ino = cpu_to_le16(ino);
+ di->i_mode = cpu_to_le32(inode->i_mode);
+ 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);
+ di->i_ctime = cpu_to_le32(inode->i_ctime.tv_sec);
+ i_sblock = BFS_I(inode)->i_sblock;
+ di->i_sblock = cpu_to_le32(i_sblock);
+ di->i_eblock = cpu_to_le32(BFS_I(inode)->i_eblock);
+ 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);
+ mutex_unlock(&info->bfs_lock);
+ return err;
+}
+
+static void bfs_evict_inode(struct inode *inode)
+{
+ unsigned long ino = inode->i_ino;
+ struct bfs_inode *di;
+ struct buffer_head *bh;
+ 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_final(&inode->i_data);
+ invalidate_inode_buffers(inode);
+ clear_inode(inode);
+
+ if (inode->i_nlink)
+ return;
+
+ di = find_inode(s, inode->i_ino, &bh);
+ if (IS_ERR(di))
+ return;
+
+ mutex_lock(&info->bfs_lock);
+ /* clear on-disk inode */
+ memset(di, 0, sizeof(struct bfs_inode));
+ mark_buffer_dirty(bh);
+ brelse(bh);
+
+ if (bi->i_dsk_ino) {
+ if (bi->i_sblock)
+ info->si_freeb += bi->i_eblock + 1 - bi->i_sblock;
+ info->si_freei++;
+ clear_bit(ino, info->si_imap);
+ bfs_dump_imap("evict_inode", s);
+ }
+
+ /*
+ * If this was the last file, make the previous block
+ * "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)
+ info->si_lf_eblk = bi->i_sblock - 1;
+ mutex_unlock(&info->bfs_lock);
+}
+
+static void bfs_put_super(struct super_block *s)
+{
+ struct bfs_sb_info *info = BFS_SB(s);
+
+ if (!info)
+ return;
+
+ mutex_destroy(&info->bfs_lock);
+ kfree(info);
+ s->s_fs_info = NULL;
+}
+
+static int bfs_statfs(struct dentry *dentry, struct kstatfs *buf)
+{
+ struct super_block *s = dentry->d_sb;
+ struct bfs_sb_info *info = BFS_SB(s);
+ u64 id = huge_encode_dev(s->s_bdev->bd_dev);
+ buf->f_type = BFS_MAGIC;
+ buf->f_bsize = s->s_blocksize;
+ buf->f_blocks = info->si_blocks;
+ buf->f_bfree = buf->f_bavail = info->si_freeb;
+ buf->f_files = info->si_lasti + 1 - BFS_ROOT_INO;
+ buf->f_ffree = info->si_freei;
+ buf->f_fsid = u64_to_fsid(id);
+ buf->f_namelen = BFS_NAMELEN;
+ return 0;
+}
+
+static struct kmem_cache *bfs_inode_cachep;
+
+static struct inode *bfs_alloc_inode(struct super_block *sb)
+{
+ struct bfs_inode_info *bi;
+ bi = kmem_cache_alloc(bfs_inode_cachep, GFP_KERNEL);
+ if (!bi)
+ return NULL;
+ return &bi->vfs_inode;
+}
+
+static void bfs_free_inode(struct inode *inode)
+{
+ kmem_cache_free(bfs_inode_cachep, BFS_I(inode));
+}
+
+static void init_once(void *foo)
+{
+ struct bfs_inode_info *bi = foo;
+
+ inode_init_once(&bi->vfs_inode);
+}
+
+static int __init init_inodecache(void)
+{
+ bfs_inode_cachep = kmem_cache_create("bfs_inode_cache",
+ sizeof(struct bfs_inode_info),
+ 0, (SLAB_RECLAIM_ACCOUNT|
+ SLAB_MEM_SPREAD|SLAB_ACCOUNT),
+ init_once);
+ if (bfs_inode_cachep == NULL)
+ return -ENOMEM;
+ return 0;
+}
+
+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);
+}
+
+static const struct super_operations bfs_sops = {
+ .alloc_inode = bfs_alloc_inode,
+ .free_inode = bfs_free_inode,
+ .write_inode = bfs_write_inode,
+ .evict_inode = bfs_evict_inode,
+ .put_super = bfs_put_super,
+ .statfs = bfs_statfs,
+};
+
+void bfs_dump_imap(const char *prefix, struct super_block *s)
+{
+#ifdef DEBUG
+ int i;
+ char *tmpbuf = (char *)get_zeroed_page(GFP_KERNEL);
+
+ if (!tmpbuf)
+ return;
+ for (i = BFS_SB(s)->si_lasti; i >= 0; i--) {
+ if (i > PAGE_SIZE - 100) break;
+ if (test_bit(i, BFS_SB(s)->si_imap))
+ strcat(tmpbuf, "1");
+ else
+ strcat(tmpbuf, "0");
+ }
+ printf("%s: lasti=%08lx <%s>\n", prefix, BFS_SB(s)->si_lasti, tmpbuf);
+ free_page((unsigned long)tmpbuf);
+#endif
+}
+
+static int bfs_fill_super(struct super_block *s, void *data, int silent)
+{
+ struct buffer_head *bh, *sbh;
+ struct bfs_super_block *bfs_sb;
+ struct inode *inode;
+ unsigned i;
+ struct bfs_sb_info *info;
+ 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;
+ s->s_time_min = 0;
+ s->s_time_max = U32_MAX;
+
+ sb_set_blocksize(s, BFS_BSIZE);
+
+ sbh = sb_bread(s, 0);
+ if (!sbh)
+ goto out;
+ 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 out1;
+ }
+ if (BFS_UNCLEAN(bfs_sb, s) && !silent)
+ printf("%s is unclean, continuing\n", s->s_id);
+
+ s->s_magic = BFS_MAGIC;
+
+ if (le32_to_cpu(bfs_sb->s_start) > le32_to_cpu(bfs_sb->s_end) ||
+ le32_to_cpu(bfs_sb->s_start) < sizeof(struct bfs_super_block) + sizeof(struct bfs_dirent)) {
+ printf("Superblock is corrupted on %s\n", s->s_id);
+ goto out1;
+ }
+
+ info->si_lasti = (le32_to_cpu(bfs_sb->s_start) - BFS_BSIZE) / sizeof(struct bfs_inode) + BFS_ROOT_INO - 1;
+ if (info->si_lasti == BFS_MAX_LASTI)
+ printf("NOTE: filesystem %s was created with 512 inodes, the real maximum is 511, mounting anyway\n", s->s_id);
+ else if (info->si_lasti > BFS_MAX_LASTI) {
+ printf("Impossible last inode number %lu > %d on %s\n", info->si_lasti, BFS_MAX_LASTI, s->s_id);
+ goto out1;
+ }
+ for (i = 0; i < BFS_ROOT_INO; i++)
+ set_bit(i, info->si_imap);
+
+ s->s_op = &bfs_sops;
+ inode = bfs_iget(s, BFS_ROOT_INO);
+ if (IS_ERR(inode)) {
+ ret = PTR_ERR(inode);
+ goto out1;
+ }
+ s->s_root = d_make_root(inode);
+ if (!s->s_root) {
+ ret = -ENOMEM;
+ goto out1;
+ }
+
+ info->si_blocks = (le32_to_cpu(bfs_sb->s_end) + 1) >> BFS_BSIZE_BITS;
+ info->si_freeb = (le32_to_cpu(bfs_sb->s_end) + 1 - 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 on %s: %lu\n", s->s_id, info->si_blocks - 1);
+ ret = -EIO;
+ goto out2;
+ }
+ 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 eblock;
+
+ if (!off) {
+ brelse(bh);
+ bh = sb_bread(s, block);
+ }
+
+ if (!bh)
+ continue;
+
+ 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 != le32_to_cpu(-1) && i_eoff > s_size) ||
+ i_sblock * BFS_BSIZE > i_eoff) {
+
+ printf("Inode 0x%08x corrupted on %s\n", i, s->s_id);
+
+ brelse(bh);
+ ret = -EIO;
+ goto out2;
+ }
+
+ if (!di->i_ino) {
+ info->si_freei++;
+ continue;
+ }
+ set_bit(i, info->si_imap);
+ info->si_freeb -= BFS_FILEBLOCKS(di);
+
+ eblock = le32_to_cpu(di->i_eblock);
+ if (eblock > info->si_lf_eblk)
+ info->si_lf_eblk = eblock;
+ }
+ brelse(bh);
+ brelse(sbh);
+ bfs_dump_imap("fill_super", s);
+ return 0;
+
+out2:
+ dput(s->s_root);
+ s->s_root = NULL;
+out1:
+ brelse(sbh);
+out:
+ mutex_destroy(&info->bfs_lock);
+ kfree(info);
+ s->s_fs_info = NULL;
+ return ret;
+}
+
+static struct dentry *bfs_mount(struct file_system_type *fs_type,
+ int flags, const char *dev_name, void *data)
+{
+ 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",
+ .mount = bfs_mount,
+ .kill_sb = kill_block_super,
+ .fs_flags = FS_REQUIRES_DEV,
+};
+MODULE_ALIAS_FS("bfs");
+
+static int __init init_bfs_fs(void)
+{
+ int err = init_inodecache();
+ if (err)
+ goto out1;
+ err = register_filesystem(&bfs_fs_type);
+ if (err)
+ goto out;
+ return 0;
+out:
+ destroy_inodecache();
+out1:
+ return err;
+}
+
+static void __exit exit_bfs_fs(void)
+{
+ unregister_filesystem(&bfs_fs_type);
+ destroy_inodecache();
+}
+
+module_init(init_bfs_fs)
+module_exit(exit_bfs_fs)